[ { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/61tfs-e6529", "eprint_status": "archive", "datestamp": "2023-12-18 16:54:06", "lastmod": "2023-12-18 16:54:06", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Luo-Yangcheng", "name": { "family": "Luo", "given": "Yangcheng" }, "orcid": "0000-0003-0983-3650" }, { "id": "Hu-Yongyun", "name": { "family": "Hu", "given": "Yongyun" }, "orcid": "0000-0002-4003-4630" }, { "id": "Yang-Jun", "name": { "family": "Yang", "given": "Jun" }, "orcid": "0000-0001-6031-2485" }, { "id": "Zhang-Michael", "name": { "family": "Zhang", "given": "Michael" } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Coupled atmospheric chemistry, radiation, and dynamics of an exoplanet generate self-sustained oscillations", "ispublished": "pub", "full_text_status": "public", "keywords": "Multidisciplinary", "note": "
\u00a9 2023 the Author(s). Published by PNAS. This article is distributed under Creative Commons Attribution-NonCommercial-NoDerivatives License 4.0 (CC BY-NC-ND).
\n\nWe thank Stuart Bartlett for composing the title of the paper, helpful discussions, and critical reading of the paper and Danica Adams for helpful discussions and critical reading of the paper. This work is supported by National Natural Science Foundation of China grant 41888101 (Y.H. and J.Y.), California Institute of Technology grant YLY.2500006-1-OAID.CITRESRCH (Y.L.), and Virtual Planetary Laboratory, the University of Washington (Y.L.Y.). Portions of the paper were developed from Y.L.'s thesis.
\n\nY.L., Y.H., and Y.L.Y. designed research; Y.L. performed research; Y.L., J.Y., and M.Z. contributed new reagents/analytic tools; Y.L., Y.H., and Y.L.Y. analyzed data; and Y.L., Y.H., and Y.L.Y. wrote the paper.
\n\nData generated from WACCM and Exo-Transmit that is used for the analysis in this study is uploaded to the CaltechDATA repository: https://doi.org/10.22002/7yh5j-c4865 (71). The stellar spectrum used in this study can be accessed at ref. 72. All other data are included in the manuscript and/or SI Appendix.
\n\nThe authors declare no competing interest.
", "abstract": "Nonlinearity in photochemical systems is known to allow self-sustained oscillations, but they have received little attention in studies of planetary atmospheres. Here, we present a unique, self-oscillatory solution for ozone chemistry of an exoplanet from a numerical simulation using a fully coupled, three-dimensional (3D) atmospheric chemistry-radiation-dynamics model. Forced with nonvarying stellar insolation and emission flux of nitric oxide (NO), atmospheric ozone abundance oscillates by a factor of thirty over a multidecadal timescale. As such self-oscillations can only occur with biological nitrogen fixation contributing to NO emission, we propose that they are a unique class of biosignature. The resulting temporal variability in the atmospheric spectrum is potentially observable. Our results underscore the importance of revisiting the spectra of exoplanets over multidecadal timescales to characterizing the atmospheric chemistry of exoplanets and searching for exoplanet biosignatures. There are also profound implications for comparative planetology and the evolution of the atmospheres of terrestrial planets in the solar system and beyond. Fully coupled, 3D atmospheric chemistry-radiation-dynamics models can reveal new phenomena that may not exist in one-dimensional models, and hence, they are powerful tools for future planetary atmospheric research.", "date": "2023-12-19", "date_type": "published", "publication": "Proceedings of the National Academy of Sciences", "volume": "120", "number": "51", "publisher": "National Academy of Sciences", "pagerange": "e2309312120", "issn": "0027-8424", "official_url": "https://authors.library.caltech.edu/records/61tfs-e6529", "funders": { "items": [ { "grant_number": "41888101" }, { "grant_number": "YLY.2500006-1-OAID.CITRESRCH" }, { "grant_number": "Virtual Planetary Laboratory" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1073/pnas.2309312120", "primary_object": { "basename": "luo-et-al-2023-coupled-atmospheric-chemistry-radiation-and-dynamics-of-an-exoplanet-generate-self-sustained-oscillations.pdf", "url": "https://authors.library.caltech.edu/records/61tfs-e6529/files/luo-et-al-2023-coupled-atmospheric-chemistry-radiation-and-dynamics-of-an-exoplanet-generate-self-sustained-oscillations.pdf" }, "related_objects": [ { "basename": "pnas.2309312120.sapp.pdf", "url": "https://authors.library.caltech.edu/records/61tfs-e6529/files/pnas.2309312120.sapp.pdf" } ], "resource_type": "article", "pub_year": "2023", "author_list": "Luo, Yangcheng; Hu, Yongyun; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/wv5t9-qry37", "eprint_status": "archive", "datestamp": "2023-10-24 23:09:39", "lastmod": "2023-10-24 23:09:39", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Zeng-Zhao-Cheng", "name": { "family": "Zeng", "given": "Zhao-Cheng" }, "orcid": "0000-0002-0008-6508" }, { "id": "Pongetti-Thomas", "name": { "family": "Pongetti", "given": "Thomas" }, "orcid": "0000-0001-9465-0853" }, { "id": "Newman-Sally", "name": { "family": "Newman", "given": "Sally" }, "orcid": "0000-0003-0710-995X" }, { "id": "Oda-Tomohiro", "name": { "family": "Oda", "given": "Tomohiro" }, "orcid": "0000-0002-8328-3020" }, { "id": "Gurney-Kevin", "name": { "family": "Gurney", "given": "Kevin" }, "orcid": "0000-0001-9218-7164" }, { "name": { "family": "Palmer", "given": "Paul I." }, "orcid": "0000-0002-1487-0969" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Sander-S-P", "name": { "family": "Sander", "given": "Stanley P." }, "orcid": "0000-0003-1424-3620" } ] }, "title": "Decadal decrease in Los Angeles methane emissions is much smaller than bottom-up estimates", "ispublished": "pub", "full_text_status": "public", "keywords": "General Physics and Astronomy; General Biochemistry, Genetics and Molecular Biology; General Chemistry; Multidisciplinary; Atmospheric chemistry; Atmospheric science", "note": "\u00a9 The Author(s) 2023. This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/.
\n\nFlask data provided by Dr. Ed Dlugokencky and Dr. Arlyn Andrews (NOAA) are greatly appreciated. Comments from K.-F. Li and J. Pinto are gratefully acknowledged. Funding is acknowledged from NASA grant 80NSSC21K1929 (T.O.) and NIST grant 70NANB19H129 (K. G.) P.I.P. acknowledges support from the UK National Centre for Earth Observation (NCEO) funded by the Natural Environment Research Council (NE/R016518/1). S.S. and T.P. acknowledge support for the CLARS facility from the NASA Earth Science Directorate and the JPL Earth Science and Technology Directorate. The research was carried out, in part, at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration (80NM0018D0004).
\n\nS.S. and Z.-C.Z designed the study. Z.-C. Z., T.P., S.S. and S.N. carried out the experiments. S.S., Z.-C.Z., P.P., Y.L.Y. and S.N. analyzed the results. T.O. and K.G. provided carbon dioxide emission inventories. Z.-C.Z. and S.S. wrote the paper. All authors reviewed the manuscript.
\n\nCLARS-FTS XCO\u2082 and XCH\u2084 data are publicly available at https://data.caltech.edu/records/254mc-zpg74 (10.22002/D1.1985). NOAA carbon cycle surface flask measurements on Mt. Wilson are available from https://gml.noaa.gov/dv/site/site.php?code=MWO and can be requested from NOAA Earth System Research Laboratories. Bottom up inventory of CO\u2082 emissions from ODIAC are publicly available from https://db.cger.nies.go.jp/dataset/ODIAC/, from California Air Resources Board are available from https://ww2.arb.ca.gov/ghg-inventory-data, and from Hestia v2.5 are publicly available from https://hestia.rc.nau.edu/; The reports of quarterly natural gas usage are publicly available from SoCalGas at https://www.socalgas.com/for-your-business/energy-savings/energy-usage-requests.
\n\nThe EEMD codes (in Matlab) used to determine the CH\u2084 emissions trends are located in the CaltechData repository at 10.22002/5f3rd-xqr42.
\n\nThe authors declare no competing interests.
\n\ns41467-023-40964-w.pdf: Published article
41467_2023_40964_MOESM1_ESM.pdf: Supplementary information
", "abstract": "Methane, a powerful greenhouse gas, has a short atmospheric lifetime (\u2009~\u200912 years), so that emissions reductions will have a rapid impact on climate forcing. In megacities such as Los Angeles (LA), natural gas (NG) leakage is the primary atmospheric methane source. The magnitudes and trends of fugitive NG emissions are largely unknown and need to be quantified to verify compliance with emission reduction targets. Here we use atmospheric remote sensing data to show that, in contrast to the observed global increase in methane emissions, LA area emissions decreased during 2011-2020 at a mean rate of (\u20131.57\u2009\u00b1\u20090.41) %/yr. However, the NG utility calculations indicate a much larger negative emissions trend of \u22125.8 %/yr. The large difference between top-down and bottom-up trends reflects the uncertainties in estimating the achieved emissions reductions. Actions taken in LA can be a blueprint for COP28 and future efforts to reduce methane emissions.
", "date": "2023-09-02", "date_type": "published", "publication": "Nature Communications", "volume": "14", "publisher": "Nature Publishing Group", "pagerange": "5353", "issn": "2041-1723", "official_url": "https://authors.library.caltech.edu/records/wv5t9-qry37", "funders": { "items": [ { "grant_number": "80NSSC21K1929" }, { "grant_number": "NE/R016518/1" }, {} ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1038/s41467-023-40964-w", "pmcid": "PMC10475107", "primary_object": { "basename": "s41467-023-40964-w.pdf", "url": "https://authors.library.caltech.edu/records/wv5t9-qry37/files/s41467-023-40964-w.pdf" }, "related_objects": [ { "basename": "41467_2023_40964_MOESM1_ESM.pdf", "url": "https://authors.library.caltech.edu/records/wv5t9-qry37/files/41467_2023_40964_MOESM1_ESM.pdf" } ], "resource_type": "article", "pub_year": "2023", "author_list": "Zeng, Zhao-Cheng; Pongetti, Thomas; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/n1b3m-5zb02", "eprint_id": 121369, "eprint_status": "archive", "datestamp": "2023-08-22 21:19:11", "lastmod": "2023-10-20 15:26:15", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Kim-S-J", "name": { "family": "Kim", "given": "S. J." } }, { "id": "Sim-C-K", "name": { "family": "Sim", "given": "C. K." } }, { "id": "Geballe-Thomas-R", "name": { "family": "Geballe", "given": "T. R." }, "orcid": "0000-0003-2824-3875" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Y. L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Miller-S", "name": { "family": "Miller", "given": "S." } }, { "id": "Lee-S", "name": { "family": "Lee", "given": "S." } }, { "id": "Tao-Chihiro", "name": { "family": "Tao", "given": "C." }, "orcid": "0000-0001-8817-0589" } ] }, "title": "Transient energetic particles as the origin of the mid-infrared north polar hotspot of Jupiter", "ispublished": "pub", "full_text_status": "public", "keywords": "Space and Planetary Science; Astronomy and Astrophysics", "note": "\u00a9 2023 Elsevier. \n\nWe are grateful to the two referees for their helpful reviews. This paper is based on observations obtained for programs GN-2012B-Q-115, GN-2020A-Q-315, GN-2021A-Q-118, and GN-2022A-Q-311 at the Gemini Observatory, which is operated by the Association of Universities for Research in Astronomy, Inc., under a cooperative agreement with the NSF on behalf of the Gemini partnership: the National Science Foundation (United States), National Research Council (Canada), CONICYT (Chile), Ministerio de Ciencia, Tecnolog\u00eda e Innovaci\u00f3n Productiva (Argentina), Minist\u00e9rio da Ci\u00eancia, Tecnologia e Inova\u00e7\u00e3o (Brazil), and KASI (Republic of Korea). This research was supported by K-GMT Science Program of KASI. Correspondence and requests for additional materials should be addressed to SJK (sjkim1@khu.ac.kr). Mr. J.K. Park helped in making Fig. 1. \n\nThis work was supported by the NRF grant (2022R1A2C1003604) funded by the Korean government (MSIT). \n\nData availability. Original observational data used in this study are publicly available on https://archive.gemini.edu \n\nThe authors declare no conflict of interest\n\nSupplemental Material - 1-s2.0-S001910352300115X-mmc1.docx
", "abstract": "Since it was detected in 1980, Jupiter's 8-\u03bcm CH\u2084 north polar hot spot (8CNPHS), \u223c20 K warmer than the surrounding polar stratosphere, has been observed for four decades. Unlike normal auroral ovals (i.e., the bright rings of auroral emissions), it is usually filled with bright emission. The causes of both its shape and longevity are not understood, although several mechanisms have been proposed to explain its existence. In order to investigate the deriving mechanism of the 8CNPHS, we have observed the north polar regions near 3 \u03bcm, where line emission from another CH\u2084 band as well as a C\u2082H\u2086 fundamental band occur. Using Gemini North/GNIRS in 2013, 2020, 2021, and 2022, we have detected transient 3-\u03bcm CH\u2084 and/or C\u2082H\u2086 bright spots within the 8CNPHS, and occasionally no apparent bright spots. By comparing the emission from CH\u2084 with that from C\u2082H\u2086, we demonstrate that the origin of the 8CNPHS must be due to transient and energetic magnetospheric particles, which can penetrate down to the hydrocarbon layers, heating the homopause (\u223c1 \u03bcbar level) and the stratosphere (\u223c1 mbar level) and energize the 8CNPHS. Based on our observations and analysis, we propose the following three mechanisms for maintaining and containing the decades long warmth of the 8CNPHS: 1) energetic and transient auroral particle precipitations warming the stratosphere of the 8CNPHS, 2) a longer radiative cooling time in the 8CNPHS stratosphere (\u223c6 months) compared to less than or equal to one month at the homopause, and 3) recently detected polar stratospheric jets likely associated with polar fronts, which resist the free flow of warm gas in the 8CNPHS to the surrounding polar regions. We show that other heating mechanisms proposed so far in the literature, such as Joule heating, polar haze heated by sunlight, etc., are only the secondary mechanisms that follow atmospheric ionization caused by energetic particle bombardment. Our finding of the magnetospheric-ionospheric-stratospheric coupling in the Jovian polar regions open the possibility of quantitatively refining 3-D global circulation models for the atmospheres of giant planets and exoplanets.", "date": "2023-07-01", "date_type": "published", "publication": "Icarus", "volume": "398", "publisher": "Elsevier", "pagerange": "Art. No. 115538", "id_number": "CaltechAUTHORS:20230510-349443100.4", "issn": "0019-1035", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230510-349443100.4", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Gemini Partnership" }, { "agency": "Ministry of Science and ICT (Korea)" }, { "agency": "National Research Foundation of Korea", "grant_number": "2022R1A2C1003604" }, { "agency": "Korea Astronomy and Space Science Institute (KASI)" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/j.icarus.2023.115538", "primary_object": { "basename": "1-s2.0-S001910352300115X-mmc1.docx", "url": "https://authors.library.caltech.edu/records/n1b3m-5zb02/files/1-s2.0-S001910352300115X-mmc1.docx" }, "resource_type": "article", "pub_year": "2023", "author_list": "Kim, S. J.; Sim, C. K.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/pyyqt-pj037", "eprint_id": 119611, "eprint_status": "archive", "datestamp": "2023-08-22 18:37:16", "lastmod": "2023-10-23 20:15:50", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Wang-Jingyu", "name": { "family": "Wang", "given": "Jingyu" }, "orcid": "0000-0001-5128-585X" }, { "id": "Fan-Siteng", "name": { "family": "Fan", "given": "Siteng" }, "orcid": "0000-0002-3041-4680" }, { "id": "Liu-Chao", "name": { "family": "Liu", "given": "Chao" }, "orcid": "0000-0001-7049-493X" }, { "id": "Natraj-Vijay", "name": { "family": "Natraj", "given": "Vijay" }, "orcid": "0000-0003-3154-9429" }, { "id": "Young-Leslie-A", "name": { "family": "Young", "given": "Leslie A." }, "orcid": "0000-0002-7547-3967" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Impacts of Organic Ice Condensation on the Optical Properties of Haze on Pluto", "ispublished": "pub", "full_text_status": "public", "keywords": "Space and Planetary Science; Earth and Planetary Sciences (miscellaneous); Geophysics; Astronomy and Astrophysics", "note": "\u00a9 2023. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. \n\nThe authors thank Drs. Maxim A. Yurkin and Alfons G. Hoekstra for their ADDA code. The simulations are conducted in the High-Performance Computing Center of Nanjing University of Information Science & Technology. This work is supported by the National Natural Science Foundation of China (grant No. 42122038). Part of this research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration (grant No. 80NM0018D0004). Y.L.Y. was supported in part by a NASA NFDAP grant (grant No. 80NSSC19K0823) to Caltech.\n\nPublished - Wang_2023_Planet._Sci._J._4_17.pdf
", "abstract": "The flyby of the New Horizons spacecraft in 2015 July revealed an unexpected cold atmosphere of Pluto and confirmed the existence of its atmospheric haze. The observed and simulated vertical profiles of chemical species and microphysical processes suggest that the haze particles in Pluto's middle and lower atmosphere may contain organic ice condensation. Such organic ice components can potentially affect Pluto's haze chemistry and optical properties, as well as its energy budget. This study investigates the influence of the ice components on the scattering properties of Pluto's haze by comparing New Horizons observations and simulated particle scattering properties. Comprehensive tests are performed for various haze particle parameters, including their size, chemical component, ice content, and morphology. Scattering properties of these ice-bearing haze particles are calculated by a discrete dipole approximation method and compared to multispectral observations obtained by four New Horizons instruments in spectral regions ranging from the ultraviolet to the near-infrared. The results indicate that the inclusion of the organic ice component leads to higher ratios of backscattering in the visible to extinction in the ultraviolet and provides better agreement with observations compared to monodispersed homogeneous aggregates. But it alone is not sufficient to explain the observed forward scattering values in the visible and near-infrared. Therefore, other scattering sources and/or mechanisms are still required to explain the full set of scattering observations. Further observations, as well as laboratory measurements and numerical tests, are anticipated to improve our understanding of the morphology and ice content of Pluto's haze.", "date": "2023-01", "date_type": "published", "publication": "Planetary Science Journal", "volume": "4", "number": "1", "publisher": "American Astronomical Society", "pagerange": "Art. No. 17", "id_number": "CaltechAUTHORS:20230301-701033500.13", "issn": "2632-3338", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230301-701033500.13", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "National Natural Science Foundation of China", "grant_number": "42122038" }, { "agency": "NASA/JPL/Caltech", "grant_number": "80NM0018D0004" }, { "agency": "NASA/Caltech", "grant_number": "80NSSC19K0823" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.3847/psj/acaf30", "primary_object": { "basename": "Wang_2023_Planet._Sci._J._4_17.pdf", "url": "https://authors.library.caltech.edu/records/pyyqt-pj037/files/Wang_2023_Planet._Sci._J._4_17.pdf" }, "resource_type": "article", "pub_year": "2023", "author_list": "Wang, Jingyu; Fan, Siteng; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/7zgjb-anm41", "eprint_id": 118620, "eprint_status": "archive", "datestamp": "2023-08-22 18:34:41", "lastmod": "2023-10-24 23:26:21", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Natraj-Vijay", "name": { "family": "Natraj", "given": "V." }, "orcid": "0000-0003-3154-9429" }, { "id": "Spurr-Robert-J-D", "name": { "family": "Spurr", "given": "R." }, "orcid": "0000-0002-6772-5992" }, { "id": "Gao-A", "name": { "family": "Gao", "given": "A." } }, { "id": "Le-T", "name": { "family": "Le", "given": "T." } }, { "id": "Zeng-Z-C", "name": { "family": "Zeng", "given": "Z. C." } }, { "id": "Fan-S", "name": { "family": "Fan", "given": "S." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Y. L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "The 2 stream-exact single scattering (2S-ESS) radiative transfer model", "ispublished": "pub", "full_text_status": "public", "keywords": "Spectroscopy; Atomic and Molecular Physics, and Optics; Radiation", "note": "A portion of this research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration (80NM0018D0004). VN acknowledges support from the Tropospheric Ozone and its Precursors from Earth System Sounding (TROPESS) project. The authors gratefully acknowledge the insightful and constructive comments from the two anonymous reviewers, which improved the clarity and quality of the manuscript.", "abstract": "The plane-parallel two-stream approximation is a popular radiative transfer approach for the calculation of fluxes and heating rates. However, it is typically not accurate enough for remote sensing applications involving the analysis of hyperspectral radiances. We present the 2 stream-exact single scattering (2S-ESS) radiative transfer model, which performs an exact calculation of single scattering in a spherically curved medium using an accurate treatment of the phase function and curved ray-tracing of the solar and line-of-sight paths, while approximating multiple scattering with the plane-parallel two-stream approach.\n\nThe 2S-ESS model has three important features. First, it can be deployed for calculations in vertically inhomogeneous atmospheres. Second, the sphericity capability makes it applicable to large solar and/or viewing zenith angle scenarios such as those encountered close to sunrise or sunset. Third, it is fully linearized: in addition to generating radiances, the model can also compute Jacobians analytically with respect to any atmospheric or surface property (e.g., trace gases, aerosols and surface reflectance). These features of the model are especially useful for remote sensing retrieval applications.\n\nWe examine the accuracy of this model for homogeneous slab and inhomogeneous multi-layer scenarios. The results show that this methodology introduces less than a few percent error in most situations, with the exception of heavy aerosol or cloud loading events, while providing three orders of magnitude improvement in computational efficiency. The code is publicly available along with documentation and test cases to assist the user.", "date": "2023-01", "date_type": "published", "publication": "Journal of Quantitative Spectroscopy and Radiative Transfer", "volume": "295", "publisher": "Elsevier", "pagerange": "Art. No. 108416", "id_number": "CaltechAUTHORS:20230103-817548100.15", "issn": "0022-4073", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230103-817548100.15", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA/JPL/Caltech", "grant_number": "80NM0018D0004" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/j.jqsrt.2022.108416", "resource_type": "article", "pub_year": "2023", "author_list": "Natraj, V.; Spurr, R.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/3br6q-61967", "eprint_id": 117139, "eprint_status": "archive", "datestamp": "2023-08-22 17:43:24", "lastmod": "2023-10-24 21:58:21", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Zhao-Lijun", "name": { "family": "Zhao", "given": "Lijun" }, "orcid": "0000-0002-7140-8105" }, { "id": "Wang-Yuan", "name": { "family": "Wang", "given": "Yuan" }, "orcid": "0000-0001-6657-8401" }, { "id": "Zhao-Chuanfeng", "name": { "family": "Zhao", "given": "Chuanfeng" }, "orcid": "0000-0002-5196-3996" }, { "id": "Dong-Xiquan", "name": { "family": "Dong", "given": "Xiquan" }, "orcid": "0000-0002-3359-6117" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Compensating Errors in Cloud Radiative and Physical Properties over the Southern Ocean in the CMIP6 Climate Models", "ispublished": "pub", "full_text_status": "public", "keywords": "Atmospheric Science", "note": "Drs. Yuan WANG, Xiquan DONG, and Yuk YUNG are supported by the National Science Foundation grants (Grant Nos. AGS-1700727/1700728 and 2031751/2031750). Dr. Chuanfeng ZHAO is supported by the National Natural Science Foundation of China. (Grant No. 41925022).", "abstract": "The Southern Ocean is covered by a large amount of clouds with high cloud albedo. However, as reported by previous climate model intercomparison projects, underestimated cloudiness and overestimated absorption of solar radiation (ASR) over the Southern Ocean lead to substantial biases in climate sensitivity. The present study revisits this long-standing issue and explores the uncertainty sources in the latest CMIP6 models. We employ 10-year satellite observations to evaluate cloud radiative effect (CRE) and cloud physical properties in five CMIP6 models that provide comprehensive output of cloud, radiation, and aerosol. The simulated longwave, shortwave, and net CRE at the top of atmosphere in CMIP6 are comparable with the CERES satellite observations. Total cloud fraction (CF) is also reasonably simulated in CMIP6, but the comparison of liquid cloud fraction (LCF) reveals marked biases in spatial pattern and seasonal variations. The discrepancies between the CMIP6 models and the MODIS satellite observations become even larger in other cloud macro- and micro-physical properties, including liquid water path (LWP), cloud optical depth (COD), and cloud effective radius, as well as aerosol optical depth (AOD). However, the large underestimation of both LWP and cloud effective radius (regional means \u223c20% and 11%, respectively) results in relatively smaller bias in COD, and the impacts of the biases in COD and LCF also cancel out with each other, leaving CRE and ASR reasonably predicted in CMIP6. An error estimation framework is employed, and the different signs of the sensitivity errors and biases from CF and LWP corroborate the notions that there are compensating errors in the modeled shortwave CRE. Further correlation analyses of the geospatial patterns reveal that CF is the most relevant factor in determining CRE in observations, while the modeled CRE is too sensitive to LWP and COD. The relationships between cloud effective radius, LWP, and COD are also analyzed to explore the possible uncertainty sources in different models. Our study calls for more rigorous calibration of detailed cloud physical properties for future climate model development and climate projection.", "date": "2022-09-20", "date_type": "published", "publication": "Advances in Atmospheric Sciences", "volume": "39", "publisher": "Springer", "pagerange": "2156-2171", "id_number": "CaltechAUTHORS:20220926-576500100.6", "issn": "0256-1530", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220926-576500100.6", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "AGS-1700727" }, { "agency": "NSF", "grant_number": "AGS-1700728" }, { "agency": "NSF", "grant_number": "AGS-2031751" }, { "agency": "NSF", "grant_number": "AGS-2031750" }, { "agency": "National Natural Science Foundation of China", "grant_number": "41925022" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1007/s00376-022-2036-z", "resource_type": "article", "pub_year": "2022", "author_list": "Zhao, Lijun; Wang, Yuan; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/t8zvv-6wy94", "eprint_id": 115780, "eprint_status": "archive", "datestamp": "2023-08-22 16:38:27", "lastmod": "2023-10-23 20:00:58", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Le-Tianhao", "name": { "family": "Le", "given": "Tianhao" }, "orcid": "0000-0002-6600-8270" }, { "id": "Natraj-Vijay", "name": { "family": "Natraj", "given": "Vijay" }, "orcid": "0000-0003-3154-9429" }, { "id": "Braverman-Amy-J", "name": { "family": "Braverman", "given": "Amy J." }, "orcid": "0000-0001-5127-9230" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Evaluation of Modeled Hyperspectral Infrared Spectra Against All\u2010Sky AIRS Observations Using Different Cloud Overlap Schemes", "ispublished": "pub", "full_text_status": "public", "keywords": "radiative transfer; cloud overlap; model-AIRS intercomparison; first Wasserstein distance; General Earth and Planetary Sciences; Environmental Science (miscellaneous)", "note": "\u00a9 2022. The Authors. Earth and Space Science published by Wiley Periodicals LLC on behalf of American Geophysical Union. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited. \n\nIssue Online: 01 July 2022. Version of Record online: 01 July 2022. Accepted manuscript online: 26 June 2022. Manuscript accepted: 17 June 2022. Manuscript revised: 08 June 2022. Manuscript received: 25 January 2022. \n\nThe authors would like to thank members of Prof. Yung's research group for useful comments. We also acknowledge Dr. Hartmut Aumann and Dr. Alan Geer for providing the AIRS observations and ECMWF profiles used in this study and Dr. Benjamin Johnson for helpful discussions on CRTM. A portion of this research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration (80NM0018D0004). \n\nData Availability Statement. The AIRS observations and ECMWF vertical profiles used in this study can be downloaded from https://airsteam.jpl.nasa.gov/ftp/hha/ECMWF20181101/. Figures were made with Matplotlib version 3.0.2 (Caswell et al., 2018; Hunter, 2007), available under the Matplotlib license at https://matplotlib.org/. The first Wasserstein distances were calculated using Scipy v1.0 (Virtanen et al., 2020), available at https://scipy.org/. The RT code used in this manuscript (CRTM version 2.4.0) is licensed under CC0 and published on Github: https://github.com/JCSDA/crtm.\n\n", "abstract": "Hyperspectral infrared sounding contains information about clouds, which plays an important role in modulating Earth's climate. However, there is a great deal of uncertainty in modeling the radiative effect of clouds due to its complex dependence on various parameters. Therefore, cloudy scenarios are often neglected in retrievals of infrared spectral measurements and in data assimilation. One-dimensional radiative transfer (RT) models have a limited capability to represent the cloud three-dimensional multilayer structure. This issue is typically resolved by using a multiple independent column approach, which is computationally demanding. Therefore, it is necessary to find a balance between computational speed and accuracy for infrared RT all-sky radiance simulations. In this study, we utilize the Community Radiative Transfer Model with four different cloud overlap schemes and compare against observations made by the Atmospheric Infrared Sounder (AIRS) using a statistical metric called the first Wasserstein distance. Our results show that the average cloud overlap scheme performs the best and successfully predicts the overall probability distribution of brightness temperature over nonfrozen oceans for a wide range of wavelengths. The mean absolute differences are less than 0.7 K for 846 selected AIRS channels between 790 cm\u207b\u00b9 and 1231 cm\u207b\u00b9.", "date": "2022-07", "date_type": "published", "publication": "Earth and Space Science", "volume": "9", "number": "7", "publisher": "American Geophysical Union", "pagerange": "Art. No. e2022EA002245", "id_number": "CaltechAUTHORS:20220722-768945000", "issn": "2333-5084", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220722-768945000", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA/JPL/Caltech", "grant_number": "80NM0018D0004" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2022ea002245", "primary_object": { "basename": "Earth_and_Space_Science_-_2022_-_Le_-_Evaluation_of_Modeled_Hyperspectral_Infrared_Spectra_Against_All\u2010Sky_AIRS.pdf", "url": "https://authors.library.caltech.edu/records/t8zvv-6wy94/files/Earth_and_Space_Science_-_2022_-_Le_-_Evaluation_of_Modeled_Hyperspectral_Infrared_Spectra_Against_All\u2010Sky_AIRS.pdf" }, "resource_type": "article", "pub_year": "2022", "author_list": "Le, Tianhao; Natraj, Vijay; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/3nb5m-rp643", "eprint_id": 114199, "eprint_status": "archive", "datestamp": "2023-08-22 16:15:49", "lastmod": "2023-10-23 23:24:49", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Bartlett-Stuart-J", "name": { "family": "Bartlett", "given": "Stuart" }, "orcid": "0000-0001-5680-476X" }, { "id": "Gao-Andrew-K", "name": { "family": "Gao", "given": "Andrew K." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Computation by Convective Logic Gates and Thermal Communication", "ispublished": "pub", "full_text_status": "public", "keywords": "Fluid computation, convection, logic gates, convective circuits; Artificial Intelligence; General Biochemistry, Genetics and Molecular Biology", "note": "\u00a9 2022 Massachusetts Institute of Technology.", "abstract": "We demonstrate a novel computational architecture based on fluid convection logic gates and heat flux-mediated information flows. Our previous work demonstrated that Boolean logic operations can be performed by thermally driven convection flows. In this work, we use numerical simulations to demonstrate a different , but universal Boolean logic operation (NOR), performed by simpler convective gates. The gates in the present work do not rely on obstacle flows or periodic boundary conditions, a significant improvement in terms of experimental realizability. Conductive heat transfer links can be used to connect the convective gates, and we demonstrate this with the example of binary half addition. These simulated circuits could be constructed in an experimental setting with modern, 2-dimensional fluidics equipment, such as a thin layer of fluid between acrylic plates. The presented approach thus introduces a new realm of unconventional, thermal fluid-based computation.", "date": "2022-06-09", "date_type": "published", "publication": "Artificial Life", "volume": "28", "number": "1", "publisher": "MIT Press", "pagerange": "96-107", "id_number": "CaltechAUTHORS:20220408-509798000", "issn": "1064-5462", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220408-509798000", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1162/artl_a_00358", "resource_type": "article", "pub_year": "2022", "author_list": "Bartlett, Stuart; Gao, Andrew K.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/8g4jn-n4385", "eprint_id": 114891, "eprint_status": "archive", "datestamp": "2023-08-20 07:44:38", "lastmod": "2023-10-24 15:14:49", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Parkinson-Christopher-D", "name": { "family": "Parkinson", "given": "Christopher D." }, "orcid": "0000-0002-5722-2224" }, { "id": "Bougher-Stephen-W", "name": { "family": "Bougher", "given": "Stephen W." }, "orcid": "0000-0002-4178-2729" }, { "id": "Mills-Franklin-P", "name": { "family": "Mills", "given": "Franklin P." }, "orcid": "0000-0002-4270-7333" }, { "id": "Hu-Renyu", "name": { "family": "Hu", "given": "Renyu" }, "orcid": "0000-0003-2215-8485" }, { "id": "Gronoff-Guillaume", "name": { "family": "Gronoff", "given": "Guillaume" }, "orcid": "0000-0002-0331-7076" }, { "id": "Li-Jiazheng", "name": { "family": "Li", "given": "Jiazheng" }, "orcid": "0000-0002-2563-6289" }, { "id": "Brecht-Amanda", "name": { "family": "Brecht", "given": "Amanda" }, "orcid": "0000-0002-9018-6528" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Venus as an Exoplanet: I. An Initial Exploration of the 3-D Energy Balance for a CO\u2082 Exoplanetary Atmosphere Around an M-Dwarf Star", "ispublished": "unpub", "full_text_status": "public", "note": "Attribution 4.0 International (CC BY 4.0).\n\nCDP would like to acknowledge to James Li and Danica Adams who assisted with the plotting of the figures in this paper. YLY was supported in part by an NAI Virtual Planetary Laboratory grant from the University of Washington. DJA was supported by a NASA FINESST Fellowship.\n\nSubmitted - 2205.10958.pdf
", "abstract": "The chemical evolution of an exoplanetary Venus-like atmosphere is dependent upon the ultraviolet to near ultraviolet (FUV-NUV) radiation ratio from the parent star, the balance between CO\u2082 photolysis and recombination via reactions that depend on the water abundance, and various catalytic chemical cycles. In this study, we use a three-dimensional (3-D) model to simulate conditions for a Venus-like exoplanet orbiting the M-dwarf type star GJ 436 by varying the star/planet distance and considering the resultant effects on heating/cooling and dynamics. The simulation includes the middle and upper atmosphere (<40 mbar). Overall, these model comparisons reveal that the impact of extreme ultraviolet to ultraviolet (EUV-UV) heating on the energy balance shows both radiative and dynamical processes are responsible for driving significant variations in zonal winds and global temperature profiles at < 10\u207b\u2075 mbar. More specifically, CO\u2082 15-\u03bcm cooling balances EUV/UV and Near InfraRed (NIR) heating at altitudes below 10\u207b\u2077 mbar pressure with a strong maximum balance for pressures at ~10\u207b\u2075 mbar, thus explaining the invariance of the temperature distribution at altitudes below 10\u207b\u2075 mbar pressure for all cases. Our model comparisons also show that moderate changes in NIR heating result in relatively small changes in neutral temperature in the upper atmosphere, and virtually no change in the middle atmosphere. However, with larger changes in the NIR heating profile, much greater changes in neutral temperature occur in the entire upper and middle atmosphere studied.", "date": "2022-06-01", "date_type": "published", "publisher": "arXiv", "id_number": "CaltechAUTHORS:20220524-180247871", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220524-180247871", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "University of Washington" }, { "agency": "NASA Earth and Space Science and Technology Fellowship" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.48550/arXiv.2205.10958", "primary_object": { "basename": "2205.10958.pdf", "url": "https://authors.library.caltech.edu/records/8g4jn-n4385/files/2205.10958.pdf" }, "resource_type": "monograph", "pub_year": "2022", "author_list": "Parkinson, Christopher D.; Bougher, Stephen W.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/znw4d-aje39", "eprint_id": 114880, "eprint_status": "archive", "datestamp": "2023-08-22 15:54:53", "lastmod": "2023-10-24 15:14:25", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Gu-Lixiang", "name": { "family": "Gu", "given": "Lixiang" }, "orcid": "0000-0002-3089-3706" }, { "id": "Zeng-Zhao-Cheng", "name": { "family": "Zeng", "given": "Zhao-Cheng" }, "orcid": "0000-0002-0008-6508" }, { "id": "Fan-Siteng", "name": { "family": "Fan", "given": "Siteng" }, "orcid": "0000-0002-3041-4680" }, { "id": "Natraj-Vijay", "name": { "family": "Natraj", "given": "Vijay" }, "orcid": "0000-0003-3154-9429" }, { "id": "Jiang-Jonathan-H", "name": { "family": "Jiang", "given": "Jonathan H." }, "orcid": "0000-0002-5929-8951" }, { "id": "Crisp-David", "name": { "family": "Crisp", "given": "David" }, "orcid": "0000-0002-4573-9998" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Hu-Yongyun", "name": { "family": "Hu", "given": "Yongyun" }, "orcid": "0000-0002-4003-4630" } ] }, "title": "Earth as a Proxy Exoplanet: Simulating DSCOVR/EPIC Observations Using the Earth Spectrum Simulator", "ispublished": "pub", "full_text_status": "public", "keywords": "Spectrophotometry; Radiative transfer; Exoplanets; Exoplanet surface variability; Exoplanet atmospheres; Exoplanet astronomy; Habitable planets; Earth (planet); Exoplanet atmospheric composition; Exoplanet atmospheric variability; Exoplanet surface characteristics; Exoplanet surface composition; Space and Planetary Science; Astronomy and Astrophysics", "note": "\u00a9 2022. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. \n\nReceived 2021 December 19; revised 2022 February 19; accepted 2022 March 14; published 2022 May 20. \n\nThis work was supported by the National Natural Science Foundation of China under grant 41888101. All computations were done at the High-performance Computing Platform of Peking University. A portion of this research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration (80NM0018D0004). Y.L.Y. was supported in part by a Virtual Planetary Laboratory grant from the University of Washington. S.F. acknowledges funding support from CNES. We acknowledge funding support from the NASA Exoplanet Research Program NNH18ZDA001N.\n\nPublished - Gu_2022_AJ_163_285.pdf
", "abstract": "Analyzing time-resolved disk-integrated spectral images of the Earth can provide a baseline for future exoplanet characterization. The Earth Polychromatic Imaging Camera (EPIC) onboard the Deep Space Climate Observatory (DSCOVR) provides \u223c5000 full-disk sunlit Earth images each year in ten wavelengths from the ultraviolet to the near-infrared. A whole-disk radiative transfer model can improve our understanding of the temporal variation of Earth's disk-integrated reflected radiance (\"light curves\") at different wavelengths and create a pool of possible observations of Earth-like exoplanets. We use the two-stream-exact-single-scattering line-by-line radiative transfer model to build the Earth Spectrum Simulator (ESS) and reconstruct DSCOVR/EPIC spectral observations. Atmospheric effects, such as scattering by air molecules, clouds, aerosols, and gaseous absorption, are included. Surface contributions are treated using appropriate bidirectional reflectance distribution functions. We simulate \u223c300 images in each channel for observations collected in 2016, with a spatial resolution of \u223c2000 pixels over the visible disk. ESS provides a simultaneous fit to the observed light curves, with time-averaged reflectance differences typically less than 7% and root-mean-square errors less than 1%. The only exceptions are in the oxygen absorption channels, where reflectance biases can be as large as 19.55%; this is a consequence of simplified assumptions about clouds; especially their vertical placement. We also recover principal components of the spectrophotometric light curves and correlate them with atmospheric and surface features.", "date": "2022-06", "date_type": "published", "publication": "Astronomical Journal", "volume": "163", "number": "6", "publisher": "American Astronomical Society", "pagerange": "Art. No. 285", "id_number": "CaltechAUTHORS:20220523-165124000", "issn": "0004-6256", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220523-165124000", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "National Natural Science Foundation of China", "grant_number": "41888101" }, { "agency": "NASA/JPL/Caltech", "grant_number": "80NM0018D0004" }, { "agency": "University of Washington" }, { "agency": "Centre National d'\u00c9tudes Spatiales (CNES)" }, { "agency": "NASA", "grant_number": "NNH18ZDA001N" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.3847/1538-3881/ac5e2e", "primary_object": { "basename": "Gu_2022_AJ_163_285.pdf", "url": "https://authors.library.caltech.edu/records/znw4d-aje39/files/Gu_2022_AJ_163_285.pdf" }, "resource_type": "article", "pub_year": "2022", "author_list": "Gu, Lixiang; Zeng, Zhao-Cheng; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/k2v3j-70764", "eprint_id": 115100, "eprint_status": "archive", "datestamp": "2023-08-22 16:01:22", "lastmod": "2023-10-23 19:47:47", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Li-Jing", "name": { "family": "Li", "given": "Jing" }, "orcid": "0000-0002-0540-0412" }, { "id": "Carlson-Barbara-E", "name": { "family": "Carlson", "given": "Barbara E." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Lv-Daren", "name": { "family": "Lv", "given": "Daren" } }, { "id": "Hansen-James", "name": { "family": "Hansen", "given": "James" } }, { "id": "Penner-Joyce-E", "name": { "family": "Penner", "given": "Joyce E." }, "orcid": "0000-0001-5577-452X" }, { "id": "Liao-Hong", "name": { "family": "Liao", "given": "Hong" } }, { "id": "Ramaswamy-Venkatachalam", "name": { "family": "Ramaswamy", "given": "V." }, "orcid": "0000-0002-1984-6423" }, { "id": "Kahn-Ralph-A", "name": { "family": "Kahn", "given": "Ralph A." } }, { "id": "Zhang-Peng", "name": { "family": "Zhang", "given": "Peng" }, "orcid": "0000-0002-7115-1389" }, { "id": "Dubovik-Oleg", "name": { "family": "Dubovik", "given": "Oleg" }, "orcid": "0000-0003-3482-6460" }, { "id": "Ding-Aijun", "name": { "family": "Ding", "given": "Aijun" }, "orcid": "0000-0003-4481-5386" }, { "id": "Lacis-Andrew-A", "name": { "family": "Lacis", "given": "Andrew A." } }, { "id": "Zhang-Lu", "name": { "family": "Zhang", "given": "Lu" } }, { "id": "Dong-Yueming", "name": { "family": "Dong", "given": "Yueming" } } ] }, "title": "Scattering and absorbing aerosols in the climate system", "ispublished": "pub", "full_text_status": "public", "keywords": "Atmospheric chemistry; Attribution; Nature and Landscape Conservation; Atmospheric Science; Earth-Surface Processes; Pollution", "note": "\u00a9 Springer Nature Limited 2022.\n\nAccepted 08 April 2022; Published 24 May 2022.\n\nJ.L., L.Z. and Y.D. acknowledge funding from National Natural Science Foundation of China grant nos. 41975023 and 42175144. O.D. appreciates support from the Chemical and Physical Properties of the Atmosphere Project funded by the French National Research Agency through the Programme d'Investissement d'Avenir under contract ANR-11-LABX-0005-01, the Regional Council \"Hauts-de-France\", and the European Funds for Regional Economic Development.\n\nData availability:\nCoupled Model Intercomparison Project Phase 6 (CMIP6) data used in Figs 1,3 are from the Earth System Grid Federation, available at https://esgf-node.llnl.gov/projects/cmip6. AOD and SSA data used in Fig. 1 are from Aerosol Robotic Network (AERONET), available at https://aeronet.gsfc.nasa.gov/.\n\nContributions:\nJ.L., B.E.C., A.A.L. and Y.L.Y. led the Review. J.L. wrote the initial draft and prepared Fig. 2, Box 1 and Supplementary Fig. 1. L.Z. prepared Fig. 1, Fig. 4 and Supplementary Figs 2, 3. Y.D. prepared Fig. 3 and Table 1. All authors contributed to the manuscript preparation, interpretation, discussion and writing.\n\nThe authors declare no competing interests.\n\nPeer review information:\nNature Reviews Earth & Environment thanks Fangqun Yu, Otto Hasekamp and the other, anonymous, reviewer(s) for their contribution to the peer review of this work.\n\nSupplemental Material - 43017_2022_296_MOESM1_ESM.pdf
", "abstract": "Tropospheric anthropogenic aerosols contribute the second-largest forcing to climate change, but with high uncertainty owing to their spatio-temporal variability and complicated optical properties. In this Review, we synthesize understanding of aerosol observations and their radiative and climate effects. Aerosols offset about one-third of the warming effect by anthropogenic greenhouse gases. Yet, in regions and seasons where the absorbing aerosol fraction is high \u2014 such as South America and East and South Asia \u2014 substantial atmospheric warming can occur. The internal mixing and the vertical distribution of aerosols, which alters both the direct effect and aerosol\u2013cloud interactions, might further enhance this warming. Despite extensive research in aerosol\u2013cloud interactions, there is still at least a 50% spread in total aerosol forcing estimates. This ongoing uncertainty is linked, in part, to the poor measurement of anthropogenic and natural aerosol absorption, as well as the little-understood effects of aerosols on clouds. Next-generation, space-borne, multi-angle polarization and active remote sensing, combined with in situ observations, offer opportunities to better constrain aerosol scattering, absorption and size distribution, thus, improving models to refine estimates of aerosol forcing and climate effects.", "date": "2022-06", "date_type": "published", "publication": "Nature Reviews Earth and Environment", "volume": "3", "number": "6", "publisher": "Nature Publishing Group", "pagerange": "363-379", "id_number": "CaltechAUTHORS:20220609-491860700", "issn": "2662-138X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220609-491860700", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "National Natural Science Foundation of China", "grant_number": "41975023" }, { "agency": "National Natural Science Foundation of China", "grant_number": "42175144" }, { "agency": "Agence Nationale pour la Recherche (ANR)", "grant_number": "ANR-11-LABX-0005-01" }, { "agency": "Regional Council \"Hauts-de-France\"" }, { "agency": "European Funds for Regional Economic Development" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1038/s43017-022-00296-7", "primary_object": { "basename": "43017_2022_296_MOESM1_ESM.pdf", "url": "https://authors.library.caltech.edu/records/k2v3j-70764/files/43017_2022_296_MOESM1_ESM.pdf" }, "resource_type": "article", "pub_year": "2022", "author_list": "Li, Jing; Carlson, Barbara E.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/9ntxh-kzq20", "eprint_id": 114889, "eprint_status": "archive", "datestamp": "2023-08-22 15:55:01", "lastmod": "2023-10-24 15:14:44", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Fan-Siteng", "name": { "family": "Fan", "given": "Siteng" }, "orcid": "0000-0002-3041-4680" }, { "id": "Zhao-Daniel", "name": { "family": "Zhao", "given": "Daniel" }, "orcid": "0000-0001-7779-5452" }, { "id": "Li-Cheng-CIT-Planetary Sciences", "name": { "family": "Li", "given": "Cheng" }, "orcid": "0000-0002-8280-3119" }, { "id": "Shemansky-Donald-E", "name": { "family": "Shemansky", "given": "Donald E." }, "orcid": "0000-0001-7168-871X" }, { "id": "Liang-Mao-Chang", "name": { "family": "Liang", "given": "Mao-Chang" }, "orcid": "0000-0002-5294-9344" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Seasonal Variations of Chemical Species and Haze in Titan's Upper Atmosphere", "ispublished": "pub", "full_text_status": "public", "keywords": "Planetary atmospheres; Atmospheric composition; Atmospheric variability; Upper atmosphere; Titan", "note": "\u00a9 2022. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. \n\nReceived 2021 December 17; revised 2022 April 13; accepted 2022 April 14; published 2022 June 2. \n\nThis research was supported in part by the Cassini/UVIS program via NASA grant JPL.1459109 to the California Institute of Technology and was partially supported by funding from NASA's Astrobiology Institute's proposal \"Habitability of Hydrocarbon Worlds: Titan and Beyond\" (PI R.M. Lopes). All the data and tools in this work are publicly available. Cassini/UVIS data are available on NASA PDS (pds.nasa.gov). The Python package emcee is available online (dfm.io/emcee/current). We thank Tommi T. Koskinen for sharing Cassini/UVIS results, Jun Cui for sharing Cassini/INMS results and comments, Sandrine Vinatier and Christophe Math\u00e9 for sharing Cassini/CIRS results, and Karen Willacy for sharing photochemical model results.\n\nPublished - Fan_2022_Planet._Sci._J._3_130.pdf
Submitted - 2204.07259.pdf
", "abstract": "Seasonal variation is significant in Titan's atmosphere owing to the large change of solar insolation resulting from Titan's 26.7\u00b0 axial tilt relative to the plane of Saturn's orbit. Here we present an investigation of hydrocarbon and nitrile species in Titan's upper atmosphere at 400\u20131200 km, which includes the mesosphere and the lower thermosphere, over more than one-fourth of Titan's year (2006\u20132014, L_S = 318\u00b0\u201360\u00b0), using 18 stellar occultation observations obtained by Cassini/Ultraviolet Imaging Spectrograph. Vertical profiles of eight chemical species (CH\u2084, C\u2082H\u2082, C\u2082H\u2084, C\u2082H\u2086, C\u2084H\u2082, C\u2086H\u2086, HCN, HC\u2083N) and haze particles are retrieved from these observations using an instrument forward model, which considers the technical issue of pointing motion. The Markov Chain Monte Carlo algorithm is used to obtain the posterior probability distributions of parameters in the retrieval, which inherently tests the extent to which species profiles can be constrained. The results show that no change of the species profiles is noticeable before the equinox, while the decrease of atmospheric temperature and significant upwelling in the summer hemisphere are found five terrestrial years afterward. Altitude of the detached haze layer decreases toward the vernal equinox and then disappears, and no reappearance is identified within the time range of our data, which is consistent with observations from Cassini/Imaging Science Subsystem. This study provides observational constraints on the seasonal change of Titan's upper atmosphere and suggests further investigations of the atmospheric chemistry and dynamics therein.", "date": "2022-06", "date_type": "published", "publication": "Planetary Science Journal", "volume": "3", "number": "6", "publisher": "American Astronomical Society", "pagerange": "Art. No. 130", "id_number": "CaltechAUTHORS:20220524-180241170", "issn": "2632-3338", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220524-180241170", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA/JPL/Caltech", "grant_number": "JPL.1459109" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.3847/PSJ/ac6953", "primary_object": { "basename": "2204.07259.pdf", "url": "https://authors.library.caltech.edu/records/9ntxh-kzq20/files/2204.07259.pdf" }, "related_objects": [ { "basename": "Fan_2022_Planet._Sci._J._3_130.pdf", "url": "https://authors.library.caltech.edu/records/9ntxh-kzq20/files/Fan_2022_Planet._Sci._J._3_130.pdf" } ], "resource_type": "article", "pub_year": "2022", "author_list": "Fan, Siteng; Zhao, Daniel; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/v2723-fva78", "eprint_id": 114890, "eprint_status": "archive", "datestamp": "2023-08-20 07:33:58", "lastmod": "2023-10-24 15:14:46", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Willacy-Karen", "name": { "family": "Willacy", "given": "Karen" }, "orcid": "0000-0001-6124-5974" }, { "id": "Chen-SiHe", "name": { "family": "Chen", "given": "SiHe" } }, { "id": "Adams-Danica-J", "name": { "family": "Adams", "given": "Danica J." }, "orcid": "0000-0001-9897-9680" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Vertical distribution of cyclopropenylidene and propadiene in the atmosphere of Titan", "ispublished": "unpub", "full_text_status": "public", "keywords": "Titan, photochemistry, Atmosphere: composition, Atmospheres: chemistry", "note": "\u00a9 2022. Attribution 4.0 International (CC BY 4.0).\n\nThe research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration (80NM0018D0004). It was supported by the NASA Astrobiology Institute. We thank Run-Lie Shia for help with modifying the KINETICS code used in our calculations.\n\nAccepted Version - 2204.13064.pdf
", "abstract": "Titan's atmosphere is a natural laboratory for exploring the photochemical synthesis of organic molecules. Significant recent advances in the study of the atmosphere of Titan include: (a) detection of C\u2083 molecules: C\u2083H\u2086, CH\u2082CCH\u2082, c-C\u2083H\u2082, and (b) retrieval of C\u2086H\u2086, which is formed primarily via C\u2083 chemistry, from Cassini-UVIS data. The detection of c-C\u2083H\u2082 is of particular significance since ring molecules are of great astrobiological importance. Using the Caltech/JPL KINETICS code, along with the best available photochemical rate coefficients and parameterized vertical transport, we are able to account for the recent observations. It is significant that ion chemistry, reminiscent of that in the interstellar medium, plays a major role in the production of c-C\u2083H\u2082 above 1000 km.", "date": "2022-05-31", "date_type": "published", "publisher": "arXiv", "id_number": "CaltechAUTHORS:20220524-180244525", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220524-180244525", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA/JPL/Caltech", "grant_number": "80NM0018D0004" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.48550/arXiv.2204.13064", "primary_object": { "basename": "2204.13064.pdf", "url": "https://authors.library.caltech.edu/records/v2723-fva78/files/2204.13064.pdf" }, "resource_type": "monograph", "pub_year": "2022", "author_list": "Willacy, Karen; Chen, SiHe; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/qm75b-s5s56", "eprint_id": 112284, "eprint_status": "archive", "datestamp": "2023-08-22 14:46:20", "lastmod": "2023-10-23 21:01:02", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Zhang-Xu", "name": { "family": "Zhang", "given": "Xu" } }, { "id": "Berkinsky-David-B", "name": { "family": "Berkinsky", "given": "David" }, "orcid": "0000-0002-7143-1073" }, { "id": "Markus-Charles-R", "name": { "family": "Markus", "given": "Charles R." }, "orcid": "0000-0003-2656-0017" }, { "id": "Chitturi-Sathya-R", "name": { "family": "Chitturi", "given": "Sathya R." } }, { "id": "Grieman-Frederick-J", "name": { "family": "Grieman", "given": "Frederick J." } }, { "id": "Okumura-M", "name": { "family": "Okumura", "given": "Mitchio" }, "orcid": "0000-0001-6874-1137" }, { "id": "Luo-Yangcheng", "name": { "family": "Luo", "given": "Yangcheng" }, "orcid": "0000-0003-0983-3650" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Sander-Stanley-P", "name": { "family": "Sander", "given": "Stanley P." }, "orcid": "0000-0003-1424-3620" } ] }, "title": "Reaction of methane and UV-activated perchlorate: Relevance to heterogeneous loss of methane in the atmosphere of Mars", "ispublished": "pub", "full_text_status": "restricted", "keywords": "Perchlorate; UV; Methane; Mars; Heterogeneous; Space and Planetary Science; Astronomy and Astrophysics", "note": "\u00a9 2021 Elsevier Inc. \n\nReceived 25 May 2021, Revised 18 November 2021, Accepted 30 November 2021, Available online 7 December 2021. \n\nDiscussions with Barney Ellison, Carl Percival, Fred Winiberg and Chris Webster are gratefully acknowledged. CRM is grateful for support from the Arnold O. Beckman Postdoctoral Fellowship. YLY acknowledges support by the Virtual Planetary Laboratory at the University of Washington. Thanks to the JPLVSR and Pomona College SURP programs for supporting our undergraduate students. This research was supported by the JPL Research and Technology Development Program. The research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration (80NM0018D0004). \n\nDeclaration of Competing Interest: None.", "abstract": "The absence of significant detectable signatures of organic molecules in the atmosphere and on the surface of Mars is a major unsolved puzzle. One possible explanation is that perchlorate-rich Martian soils, activated by solar ultraviolet (UV) radiation, create an environment favorable for the rapid oxidation of organics such as alkanes (including methane or CH\u2084). In this paper, we measured product formation rates from the methane-perchlorate-UV system at room temperature. Our results show that magnesium perchlorate (Mg(ClO\u2084)\u2082\u20226H\u2082O) surfaces exposed to UV light at wavelengths reaching the Mars' surface accelerate the decomposition of methane (CH\u2084), resulting in the formation of carbon dioxide (CO\u2082), carbon monoxide (CO), and volatile chlorine oxides. The production rates for CO\u2082 and CO on UV-activated perchlorate surfaces are accelerated by a factor of 2.5 and 4.5, respectively, compared to those in the absence of perchlorate. In addition, with UV radiation exposure, perchlorate (ClO\u2084\u207b) decomposes to chlorate (ClO\u2083\u207b) and chlorine oxides. These results are incorporated into a simple box model to estimate the near-surface atmospheric methane lifetime. The model gives a lower bound of the lifetime on the order of hours to days, substantially shorter than ~300\u202fyrs. calculated from methane loss by gas-phase chemistry alone.", "date": "2022-04", "date_type": "published", "publication": "Icarus", "volume": "376", "publisher": "Elsevier", "pagerange": "Art. No. 114832", "id_number": "CaltechAUTHORS:20211208-560298000", "issn": "0019-1035", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20211208-560298000", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Arnold and Mabel Beckman Foundation" }, { "agency": "University of Washington" }, { "agency": "Pomona College" }, { "agency": "JPL Research and Technology Development Fund" }, { "agency": "NASA", "grant_number": "80NM0018D0004" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/j.icarus.2021.114832", "resource_type": "article", "pub_year": "2022", "author_list": "Zhang, Xu; Berkinsky, David; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/8vhq9-2yn28", "eprint_id": 113335, "eprint_status": "archive", "datestamp": "2023-08-22 14:17:17", "lastmod": "2023-10-23 23:02:55", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Bartlett-Stuart-J", "name": { "family": "Bartlett", "given": "Stuart" }, "orcid": "0000-0001-5680-476X" }, { "id": "Li-Jiazheng", "name": { "family": "Li", "given": "Jiazheng" }, "orcid": "0000-0002-2563-6289" }, { "id": "Gu-Lixiang", "name": { "family": "Gu", "given": "Lixiang" }, "orcid": "0000-0002-3089-3706" }, { "id": "Sinapayen-Lana", "name": { "family": "Sinapayen", "given": "Lana" }, "orcid": "0000-0003-2270-2954" }, { "id": "Fan-Siteng", "name": { "family": "Fan", "given": "Siteng" }, "orcid": "0000-0002-3041-4680" }, { "id": "Natraj-Vijay", "name": { "family": "Natraj", "given": "Vijay" }, "orcid": "0000-0003-3154-9429" }, { "id": "Jiang-Jonathan-H", "name": { "family": "Jiang", "given": "Jonathan H." }, "orcid": "0000-0002-5929-8951" }, { "id": "Crisp-David", "name": { "family": "Crisp", "given": "David" }, "orcid": "0000-0002-4573-9998" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Assessing planetary complexity and potential agnostic biosignatures using epsilon machines", "ispublished": "pub", "full_text_status": "public", "keywords": "Astrobiology; Exoplanets; Information theory and computation; Time-domain astronomy; Astronomy and Astrophysics", "note": "\u00a9 The Author(s), under exclusive licence to Springer Nature Limited 2022. \n\nReceived 26 December 2020. Accepted 12 November 2021. Published 07 February 2022. \n\nWe acknowledge partial funding support from the NASA Exoplanet Research Program NNH18ZDA001N-2XRP. A portion of this research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with NASA (80NM0018D0004). Y.L.Y. was supported in part by an NAI Virtual Planetary Laboratory grant from the University of Washington. We thank the members of the Caltech GPS 'Astrobiothermoevoinfo' reading group for the various inspiring discussions that have helped catalyse ideas such as those presented here. We also thank T. Ewald at Caltech for valuable help with the processing of Jupiter data from Cassini. Finally, S.B. thanks S. Bullock for being his guide into the world of complexity. \n\nContributions. S.B. conceived of the idea of using EMR to analyse planetary complexity and the hypothesized correlation between planetary complexity and the presence of life. He performed the complexity analysis, produced the figures and wrote the manuscript. J.L. provided the Jupiter Cassini data. L.G. and S.F. produced the synthetic Earth and recomposed datasets. L.S. assisted with the complexity analysis, results interpretation, literature review and manuscript editing. V.N. assisted with results interpretation and manuscript editing. J.H.J., D.C. and Y.L.Y. provided essential guidance, assistance with data provision, results interpretation and manuscript editing. \n\nData availability. Source data for all time series as well as the data points in the figures in the main text are provided with this paper. \n\nCode availability. C++ code for the EMR process used in this study can be accessed here: https://nicolas.brodu.net/recherche/decisional_states/index.html. \n\nThe authors declare no competing interests. \n\nPeer review information. Nature Astronomy thanks Cole Mathis and the other, anonymous, reviewer(s) for their contribution to the peer review of this work.\n\nSubmitted - 2202.03699.pdf
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", "abstract": "We present a new approach to exoplanet characterization using techniques from complexity science, with potential applications to biosignature detection. This agnostic method makes use of the temporal variability of light reflected or emitted from a planet. We use a technique known as epsilon machine reconstruction to compute the statistical complexity, a measure of the minimal model size for time series data. We demonstrate that statistical complexity is an effective measure of the complexity of planetary features. Increasing levels of qualitative planetary complexity correlate with increases in statistical complexity and Shannon entropy, demonstrating that our approach can identify planets with the richest dynamics. We also compare Earth time series with Jupiter data, and find that for the three wavelengths considered Earth's average complexity and entropy rate are approximately 50% and 43% higher than Jupiter's, respectively. The majority of schemes for the detection of extraterrestrial life rely upon biochemical signatures and planetary context. However, it is increasingly recognized that extraterrestrial life could be very different from life on Earth. Under the hypothesis that there is a correlation between the presence of a biosphere and observable planetary complexity, our technique offers an agnostic and quantitative method for the measurement thereof.", "date": "2022-03", "date_type": "published", "publication": "Nature Astronomy", "volume": "6", "number": "3", "publisher": "Nature Publishing Group", "pagerange": "387-392", "id_number": "CaltechAUTHORS:20220208-948270000", "issn": "2397-3366", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220208-948270000", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NNH18ZDA001N-2XRP" }, { "agency": "NASA/JPL/Caltech", "grant_number": "80NM0018D0004" }, { "agency": "University of Washington" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1038/s41550-021-01559-x", "primary_object": { "basename": "41550_2021_1559_Fig4_ESM.jpg", "url": "https://authors.library.caltech.edu/records/8vhq9-2yn28/files/41550_2021_1559_Fig4_ESM.jpg" }, "related_objects": [ { "basename": "41550_2021_1559_Fig5_ESM.jpg", "url": "https://authors.library.caltech.edu/records/8vhq9-2yn28/files/41550_2021_1559_Fig5_ESM.jpg" }, { "basename": "41550_2021_1559_Fig6_ESM.jpg", "url": "https://authors.library.caltech.edu/records/8vhq9-2yn28/files/41550_2021_1559_Fig6_ESM.jpg" }, { "basename": "41550_2021_1559_MOESM1_ESM.pdf", "url": "https://authors.library.caltech.edu/records/8vhq9-2yn28/files/41550_2021_1559_MOESM1_ESM.pdf" }, { "basename": "41550_2021_1559_MOESM2_ESM.csv", "url": "https://authors.library.caltech.edu/records/8vhq9-2yn28/files/41550_2021_1559_MOESM2_ESM.csv" }, { "basename": "41550_2021_1559_MOESM3_ESM.csv", "url": "https://authors.library.caltech.edu/records/8vhq9-2yn28/files/41550_2021_1559_MOESM3_ESM.csv" }, { "basename": "2202.03699.pdf", "url": "https://authors.library.caltech.edu/records/8vhq9-2yn28/files/2202.03699.pdf" }, { "basename": "41550_2021_1559_Fig3_ESM.jpg", "url": "https://authors.library.caltech.edu/records/8vhq9-2yn28/files/41550_2021_1559_Fig3_ESM.jpg" } ], "resource_type": "article", "pub_year": "2022", "author_list": "Bartlett, Stuart; Li, Jiazheng; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/sasvk-pcg30", "eprint_id": 113069, "eprint_status": "archive", "datestamp": "2023-08-22 14:16:39", "lastmod": "2023-10-23 22:54:51", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Chen-Sihe", "name": { "family": "Chen", "given": "Sihe" } }, { "id": "Natraj-Vijay", "name": { "family": "Natraj", "given": "Vijay" }, "orcid": "0000-0003-3154-9429" }, { "id": "Zeng-Zhao-Cheng", "name": { "family": "Zeng", "given": "Zhao-Cheng" }, "orcid": "0000-0002-0008-6508" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Machine learning-based aerosol characterization using OCO-2 O\u2082 A-band observations", "ispublished": "pub", "full_text_status": "restricted", "keywords": "OCO-2; Aerosol; Critical albedo; CALIPSO; Machine learning; O2-A Band; Spectroscopy; Atomic and Molecular Physics, and Optics; Radiation", "note": "\u00a9 2022 Published by Elsevier Ltd. \n\nReceived 27 August 2021, Revised 18 November 2021, Accepted 21 December 2021, Available online 26 December 2021. \n\nA portion of this research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration (80NM0018D0004). VN acknowledges support from the NASA Earth Science US Participating Investigator program (solicitation NNH16ZDA001N-ESUSPI). We thank D. Crisp, C. E. Miller, M. Gunson and S. Sander for stimulating discussions. \n\nAuthor Contributions. S. C. devised the machine learning method, conducted the data curation, performed the analysis, and wrote the manuscript. V. N. conceived the project, supervised the work, and revised the manuscript. Z. Z. developed the spectral sorting method, revised the manuscript, and provided suggestions on visualization. Y. Y. co-supervised the work and revised the manuscript. \n\nThe authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.", "abstract": "Aerosol scattering influences the retrieval of the column-averaged dry-air mole fraction of CO\u2082 (XCO\u2082) from the Orbiting Carbon Observatory-2 (OCO-2). This is especially true for surfaces with reflectance close to a critical value where there is very low sensitivity to aerosol loading. A spectral sorting approach was introduced to improve the characterization of aerosols over coastal regions. Here, we generalize this procedure to land surfaces and use a two-step neural network to retrieve aerosol parameters from OCO-2 measurements. We show that, by using a combination of radiance measurements in the continuum and inside the absorption band, both the aerosol optical depth and layer height, as well as their uncertainties, can be accurately predicted. Using the improved aerosol estimates as a priori, we demonstrate that the accuracy of the XCO\u2082 retrieval can be significantly improved compared to the OCO-2 Level-2 Standard product. Furthermore, using simulated observations, we obtain estimates of the error in the retrieved XCO\u2082. These simulations indicate that the bias-corrected OCO-2 Lite data, which is used for flux inversions, may have remaining biases due to interference of aerosol effects.", "date": "2022-03", "date_type": "published", "publication": "Journal of Quantitative Spectroscopy and Radiative Transfer", "volume": "279", "publisher": "Elsevier", "pagerange": "Art. No. 108049", "id_number": "CaltechAUTHORS:20220121-968317000", "issn": "0022-4073", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220121-968317000", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA/JPL/Caltech", "grant_number": "80NM0018D0004" }, { "agency": "NASA", "grant_number": "NNH16ZDA001N-ESUSPI" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/j.jqsrt.2021.108049", "resource_type": "article", "pub_year": "2022", "author_list": "Chen, Sihe; Natraj, Vijay; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/hnhc3-4kb03", "eprint_id": 113954, "eprint_status": "archive", "datestamp": "2023-10-09 21:00:13", "lastmod": "2023-10-24 16:30:10", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Zhou-Ganning", "name": { "family": "Zhou", "given": "Ganning" } }, { "id": "Wang-Jianjie", "name": { "family": "Wang", "given": "Jianjie" } }, { "id": "Yin-Yan", "name": { "family": "Yin", "given": "Yan" }, "orcid": "0000-0002-8391-2712" }, { "id": "Hu-Xiuqing", "name": { "family": "Hu", "given": "Xiuqing" } }, { "id": "Letu-Husi", "name": { "family": "Letu", "given": "Husi" }, "orcid": "0000-0002-7336-8872" }, { "id": "Sohn-Byung-Ju", "name": { "family": "Sohn", "given": "Byung-Ju" }, "orcid": "0000-0001-6134-3515" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Liu-Chao", "name": { "family": "Liu", "given": "Chao" }, "orcid": "0000-0001-7049-493X" } ] }, "title": "Detecting Supercooled Water Clouds Using Passive Radiometer Measurements", "ispublished": "pub", "full_text_status": "public", "keywords": "cloud properties; supercooled water clouds; passive radiometers; General Earth and Planetary Sciences; Geophysics", "note": "\u00a9 2022. American Geophysical Union. \n\nIssue Online: 14 February 2022. Version of Record online: 14 February 2022. Accepted manuscript online: 18 January 2022. Manuscript accepted: 14 January 2022. Manuscript revised: 23 November 2021. Manuscript received: 14 September 2021. \n\nThe authors acknowledge the funding supported by the National Natural Science Foundation of China (42122038 and 42105135). B. J. Sohn was supported by the National Research Foundation of Korea (NRF) under Grant NRF-2021R1A4A5032320. \n\nData Availability Statement. All data related to this work are available online. The VIIRS and CloudSat-CALIPSO data can be obtained from the National Aeronautics and Space Administration (NASA) LAADS DAAC (https://ladsweb.modaps.eosdis.nasa.gov/), ICARE data and services center (https://www.icare.univ-lille.fr/data-access/data-archive-access/). The results from this study can be downloaded from: https://doi.org/10.5281/zenodo.5717688.\n\nPublished - 2021GL096111.pdf
Supplemental Material - 2021gl096111-sup-0001-supporting_information_si-s01.docx
", "abstract": "Supercooled water clouds (SWCs) have significant impacts on the Earth's radiation balance, aircraft ice accretion and precipitation augmentation. This study introduces an efficient algorithm to detect SWCs from passive radiometers, which combines information from the reflectance difference between 1.61 and 2.25 \u03bcm channels, the brightness temperature difference between the 8.5 and 11 \u03bcm channels, and the cloud top temperature. Validated by space radar and lidar measurements, our algorithm can correctly detect 91% of SWC pixels, better than current Visible Infrared Imager Radiometer Suite operational product. SWCs are found mostly over the mid- to high-latitude oceans and have a global occurrence frequency of \u223c8% in cloudy skies. Since the channels used for the detection are available in most current operational polar and geostationary satellite radiometers, this SWC detection algorithm can be easily implemented for operations such as cloud monitoring, aviation safety, and SWC-related weather modification.", "date": "2022-02-28", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "49", "number": "4", "publisher": "American Geophysical Union", "pagerange": "Art. No. e2021GL096111", "id_number": "CaltechAUTHORS:20220317-377264000", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220317-377264000", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "National Natural Science Foundation of China", "grant_number": "42122038" }, { "agency": "National Natural Science Foundation of China", "grant_number": "42105135" }, { "agency": "National Research Foundation of Korea", "grant_number": "NRF-2021R1A4A5032320" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2021gl096111", "primary_object": { "basename": "2021gl096111-sup-0001-supporting_information_si-s01.docx", "url": "https://authors.library.caltech.edu/records/hnhc3-4kb03/files/2021gl096111-sup-0001-supporting_information_si-s01.docx" }, "related_objects": [ { "basename": "2021GL096111.pdf", "url": "https://authors.library.caltech.edu/records/hnhc3-4kb03/files/2021GL096111.pdf" } ], "resource_type": "article", "pub_year": "2022", "author_list": "Zhou, Ganning; Wang, Jianjie; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/dgztg-n6f61", "eprint_id": 112830, "eprint_status": "archive", "datestamp": "2023-09-15 07:21:59", "lastmod": "2023-10-23 21:34:25", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Fan-Siteng", "name": { "family": "Fan", "given": "Siteng" }, "orcid": "0000-0002-3041-4680" }, { "id": "Gao-Peter", "name": { "family": "Gao", "given": "Peter" }, "orcid": "0000-0002-8518-9601" }, { "id": "Zhang-Xi", "name": { "family": "Zhang", "given": "Xi" }, "orcid": "0000-0002-8706-6963" }, { "id": "Adams-Danica-J", "name": { "family": "Adams", "given": "Danica J." }, "orcid": "0000-0001-9897-9680" }, { "id": "Kutsop-Nicholas-W", "name": { "family": "Kutsop", "given": "Nicholas W." }, "orcid": "0000-0001-7188-9044" }, { "id": "Bierson-Carver-J", "name": { "family": "Bierson", "given": "Carver J." }, "orcid": "0000-0002-6840-7187" }, { "id": "Liu-Chao", "name": { "family": "Liu", "given": "Chao" } }, { "id": "Yang-Jiani", "name": { "family": "Yang", "given": "Jiani" }, "orcid": "0000-0003-0037-2413" }, { "id": "Young-Leslie-A", "name": { "family": "Young", "given": "Leslie A." }, "orcid": "0000-0002-7547-3967" }, { "id": "Cheng-Andrew-F", "name": { "family": "Cheng", "given": "Andrew F." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "A bimodal distribution of haze in Pluto's atmosphere", "ispublished": "pub", "full_text_status": "public", "keywords": "Asteroids, comets and Kuiper belt; Atmospheric chemistry; Atmospheric dynamics; General Physics and Astronomy; General Biochemistry, Genetics and Molecular Biology; General Chemistry", "note": "\u00a9 The Author(s) 2022. This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/. \n\nReceived 22 September 2021; Accepted 22 November 2021; Published 11 January 2022. \n\nWe thank William M. Grundy for sharing the LEISA data, Michael L. Wong and Xue Feng for improving figure representations, and Yan Wu for comments. P.G. is supported by NASA Hubble Fellowship grant HST-HF2-51456.001-A awarded by the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., for NASA, under contract NAS5-26555. X.Z. is supported by NASA Solar System Workings Grant 80NSSC19K0791. A.F.C. is supported by NASA under the New Horizons Project. \n\nData availability: The New Horizons observations are available on NASA PDS (https://pds-smallbodies.astro.umd.edu/data_sb/missions/newhorizons/index.shtml). The measured haze optical properties are in Khare et al. 38. The processed observations, including the extinction and scattering intensities, are attached in the Supplementary Information. The retrieved parameters describing haze morphology and corresponding scattering properties are also attached in the Supplementary Information. Source data are provided with this paper. \n\nCode availability: The data processing procedure is described step by step in the Methods. The Python package emcee for implementing MCMC is available at https://emcee.readthedocs.io. The haze scattering model is described in the appendix of Tomasko et al.10. The sphere pixelation tool is available at https://healpix.sourceforge.io. \n\nAuthor Contributions: S.F. conducted the data analysis, performed the calculations, and wrote the manuscript. S.F., P.G., X.Z., and Y.L.Y. conceived and designed the research. P.G. and D.J.A. provided the microphysical model. P.G. and C.L. provided the aggregate scattering model. X.Z. originated the idea of bi-modality. N.W.K. and C.J.B. contributed to the analysis of MVIC data. J.Y. contributed to interpreting and presenting the retrieval results. L.A.Y. and A.F.C provided insights into interpreting New Horizons observations. All authors contributed to the manuscript writing. \n\nThe authors declare no competing interests. \n\nPeer review information: Nature Communications thanks Kathleen Mandt and the anonymous reviewer(s) for their contribution to the peer review of this work. Peer reviewer reports are available.\n\nPublished - s41467-021-27811-6.pdf
Accepted Version - 2201.04392.pdf
Supplemental Material - 41467_2021_27811_MOESM1_ESM.pdf
Supplemental Material - 41467_2021_27811_MOESM2_ESM.pdf
Supplemental Material - 41467_2021_27811_MOESM3_ESM.zip
", "abstract": "Pluto, Titan, and Triton make up a unique class of solar system bodies, with icy surfaces and chemically reducing atmospheres rich in organic photochemistry and haze formation. Hazes play important roles in these atmospheres, with physical and chemical processes highly dependent on particle sizes, but the haze size distribution in reducing atmospheres is currently poorly understood. Here we report observational evidence that Pluto's haze particles are bimodally distributed, which successfully reproduces the full phase scattering observations from New Horizons. Combined with previous simulations of Titan's haze, this result suggests that haze particles in reducing atmospheres undergo rapid shape change near pressure levels ~0.5\u2009Pa and favors a photochemical rather than a dynamical origin for the formation of Titan's detached haze. It also demonstrates that both oxidizing and reducing atmospheres can produce multi-modal hazes, and encourages reanalysis of observations of hazes on Titan and Triton.", "date": "2022-01-11", "date_type": "published", "publication": "Nature Communications", "volume": "13", "publisher": "Nature Publishing Group", "pagerange": "Art. No. 240", "id_number": "CaltechAUTHORS:20220111-721365800", "issn": "2041-1723", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220111-721365800", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA Hubble Fellowship", "grant_number": "HST-HF2-51456.001-A" }, { "agency": "NASA", "grant_number": "NAS5-26555" }, { "agency": "NASA", "grant_number": "80NSSC19K0791" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1038/s41467-021-27811-6", "pmcid": "PMC8752795", "primary_object": { "basename": "2201.04392.pdf", "url": "https://authors.library.caltech.edu/records/dgztg-n6f61/files/2201.04392.pdf" }, "related_objects": [ { "basename": "41467_2021_27811_MOESM1_ESM.pdf", "url": "https://authors.library.caltech.edu/records/dgztg-n6f61/files/41467_2021_27811_MOESM1_ESM.pdf" }, { "basename": "41467_2021_27811_MOESM2_ESM.pdf", "url": "https://authors.library.caltech.edu/records/dgztg-n6f61/files/41467_2021_27811_MOESM2_ESM.pdf" }, { "basename": "41467_2021_27811_MOESM3_ESM.zip", "url": "https://authors.library.caltech.edu/records/dgztg-n6f61/files/41467_2021_27811_MOESM3_ESM.zip" }, { "basename": "s41467-021-27811-6.pdf", "url": "https://authors.library.caltech.edu/records/dgztg-n6f61/files/s41467-021-27811-6.pdf" } ], "resource_type": "article", "pub_year": "2022", "author_list": "Fan, Siteng; Gao, Peter; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/3cjh8-jyx53", "eprint_id": 112361, "eprint_status": "archive", "datestamp": "2023-08-22 13:03:08", "lastmod": "2023-10-23 17:51:41", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Albright-Ronald", "name": { "family": "Albright", "given": "Ronald" } }, { "id": "Corbett-Abigail", "name": { "family": "Corbett", "given": "Abigail" } }, { "id": "Jiang-Xun", "name": { "family": "Jiang", "given": "Xun" }, "orcid": "0000-0001-8932-3807" }, { "id": "Creecy-Ellen", "name": { "family": "Creecy", "given": "Ellen" }, "orcid": "0000-0003-4525-2896" }, { "id": "Newman-Sally", "name": { "family": "Newman", "given": "Sally" }, "orcid": "0000-0003-0710-995X" }, { "id": "Li-King-Fai", "name": { "family": "Li", "given": "King-Fai" }, "orcid": "0000-0003-0150-2910" }, { "id": "Liang-Mao-Chang", "name": { "family": "Liang", "given": "Mao-Chang" }, "orcid": "0000-0002-5294-9344" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Seasonal Variations of Solar-Induced Fluorescence, Precipitation, and Carbon Dioxide Over the Amazon", "ispublished": "pub", "full_text_status": "public", "keywords": "Photosynthesis; burned area; vapor pressure deficit; biosphere-atmosphere exchange; General Earth and Planetary Sciences; Environmental Science (miscellaneous)", "note": "\u00a9 2021 The Authors. Earth and Space Science published by Wiley Periodicals LLC on behalf of American Geophysical Union. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited. \n\nIssue Online: 18 January 2022; Version of Record online: 18 January 2022; Accepted manuscript online: 09 December 2021; Manuscript accepted: 24 November 2021; Manuscript revised: 20 November 2021; Manuscript received: 12 October 2021. \n\nThe authors thank two anonymous referees and the editor for their time and constructive suggestions. The authors thank Dr. L. Li and Dr. H. Ajami for their help to this article. X. Jiang is supported by NASA ROSES NNH15ZDA001N-PDART Program. Y. L. Yung is supported by the NASA Science Team for the OCO-2 Mission. K.-F. Li is partially supported by NASA JPL Subcontracts 1631379 and 1653138. M.-C. Liang is supported by Ministry of Science and Technology, Taiwan (Grant 108-2111-M-001-011-MY3) and Academia Sinica (Grant AS-IA-109-M03). \n\n\nData Availability Statement: GPCP Version 2.3 precipitation data can be downloaded at https://psl.noaa.gov/data/gridded/data.gpcp.html. OCO-2 Version 10 SIF and column CO\u2082 data can be downloaded at https://co2.jpl.nasa.gov/#mission=OCO-2. MODIS burned area data can be downloaded at http://modis-fire.umd.edu/ (Please see Section 4.1 of the User's Manual for details - https://modis-fire.umd.edu/files/MODIS_C6_BA_User_Guide_1.3.pdf).\n\nSupplemental Material - 2021ea002078-sup-0001-supporting_information_si-s01.docx
", "abstract": "Previous studies suggested that the Amazon, the largest rainforest on Earth, changes from a CO\u2082 sink to a CO\u2082 source during the dry/fire season. However, the biospheric contributions to atmospheric CO\u2082 are not well understood during the two main seasons, the dry/fire season and the wet season. In this article, we utilize Orbiting Carbon Observatory 2 (OCO-2) Solar-Induced Fluorescence (SIF) to explore photosynthetic activity during the different seasons. The spatiotemporal variability of OCO-2 SIF, OCO-2 CO\u2082, precipitation, and burned area are investigated over the Amazon from September 2014 to December 2019. Averaging over the entire Amazon region, we found a positive temporal correlation (0.94) between OCO-2 SIF and Global Precipitation Climatology Project precipitation and a negative temporal correlation (\u22120.64) between OCO-2 SIF and OCO-2 CO\u2082, consistent with the fact that precipitation enhances photosynthesis, which results in higher values for SIF and rate of removal of CO\u2082 from the atmosphere above the Amazon region. We also observed seasonality in the spatial variability of these variables within the Amazon region. During the dry/fire (August\u2013October) season, low SIF values, low precipitation, high vapor pressure deficit (VPD), large burned areas, and high atmospheric CO\u2082 are mainly found over the southern Amazon region. In contrast, during the wet season (January\u2013March), high SIF values, high precipitation, low VPD, smaller burned areas, and low CO\u2082 are found over both the central and southern Amazon regions. The seasonal difference in SIF suggests that photosynthetic activity is reduced during the dry/fire season relative to the wet season as a result of low precipitation and high VPD, especially over the southern Amazon region, which will contribute to more CO\u2082 in the atmosphere during the dry/fire season.", "date": "2022-01", "date_type": "published", "publication": "Earth and Space Science", "volume": "9", "number": "1", "publisher": "American Geophysical Union", "pagerange": "Art. No. e2021EA002078", "id_number": "CaltechAUTHORS:20211210-240694000", "issn": "2333-5084", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20211210-240694000", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NNH15ZDA001N-PDART" }, { "agency": "JPL", "grant_number": "1631379" }, { "agency": "JPL", "grant_number": "1653138" }, { "agency": "Ministry of Science and Technology (Taipei)", "grant_number": "108-2111-M-001-011-MY3" }, { "agency": "Academia Sinica", "grant_number": "AS-IA-109-M03" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2021ea002078", "primary_object": { "basename": "2021ea002078-sup-0001-supporting_information_si-s01.docx", "url": "https://authors.library.caltech.edu/records/3cjh8-jyx53/files/2021ea002078-sup-0001-supporting_information_si-s01.docx" }, "related_objects": [ { "basename": "Earth_and_Space_Science_-_2021_-_Albright_-_Seasonal_Variations_of_Solar_u2010Induced_Fluorescence_Precipitation_and_Carbon.pdf", "url": "https://authors.library.caltech.edu/records/3cjh8-jyx53/files/Earth_and_Space_Science_-_2021_-_Albright_-_Seasonal_Variations_of_Solar_u2010Induced_Fluorescence_Precipitation_and_Carbon.pdf" } ], "resource_type": "article", "pub_year": "2022", "author_list": "Albright, Ronald; Corbett, Abigail; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/9txaz-ptm62", "eprint_id": 112448, "eprint_status": "archive", "datestamp": "2023-08-22 12:48:38", "lastmod": "2023-10-23 22:32:53", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Liang-Mao-Chang", "name": { "family": "Liang", "given": "Mao-Chang" }, "orcid": "0000-0002-5294-9344" }, { "id": "Chen-Yi-Chun", "name": { "family": "Chen", "given": "Yi-Chun" }, "orcid": "0000-0001-7997-8578" }, { "id": "Gao-Yi-Qin", "name": { "family": "Gao", "given": "Yi-Qin" } }, { "id": "Zhang-Xi", "name": { "family": "Zhang", "given": "Xi" } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Atmospheric Effects on the Isotopic Composition of Ozone", "ispublished": "pub", "full_text_status": "public", "keywords": "ozone; mass-independent effect; Harley and Huggins bands; Chappuis band; photochemistry; pollution chemistry; Atmospheric Science; Environmental Science (miscellaneous)", "note": "\u00a9 2021 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/). \n\nReceived: 10 November 2021 / Revised: 3 December 2021 / Accepted: 10 December 2021 / Published: 13 December 2021. \n\n(This article belongs to the Special Issue Feature Papers in Atmosphere Science).\n\nWe thank D. Krankowsky for providing the in situ measured temperatures. \n\nThis research was supported in part by MOST Grants 108-2111-M-001-011-MY3, 109-2111-M-001-009-, 110-2111-M-001-012-, and 110-2111-M-001-015 to Academia Sinica and an Academia Sinica Grant AS-IA-109-M03. X.Z. was supported by National Science Foundation Grant AGS-1901126 to the University of California, Santa Cruz. Y.L.Y. was supported in part an NAI Virtual Planetary Laboratory Grant from the University of Washington to the Jet Propulsion Laboratory and California Institute of Technology. \n\nAuthor Contributions. Conceptualization, M.-C.L. and Y.L.Y.; methodology, M.-C.L., Y.-C.C., Y.-Q.G., X.Z. and Y.L.Y.; validation, M.-C.L.; formal analysis, M.-C.L., Y.-C.C. and X.Z.; investigation, M.-C.L., Y.-C.C. and X.Z.; data curation, M.-C.L., Y.-C.C. and X.Z.; writing\u2014original draft preparation, M.-C.L.; writing\u2014review and editing, M.-C.L., Y.-C.C., X.Z. and Y.L.Y.; visualization, M.-C.L., Y.-C.C. and X.Z.; funding acquisition, M.-C.L. All authors have read and agreed to the published version of the manuscript. \n\nData Availability Statement. The data used in the paper are either provided in the table or taken from the published papers refereed. \n\nInstitutional Review Board Statement. Not applicable. \n\nInformed Consent Statement. Not applicable. \n\nThe authors declare no conflict of interest.\n\nPublished - atmosphere-12-01673.pdf
", "abstract": "The delta values of the isotope composition of atmospheric ozone is ~100\u2030 (referenced to atmospheric O\u2082). Previous photochemical models, which considered the isotope fractionation processes from both formation and photolysis of ozone, predicted \u03b4\u2074\u2079O\u2083 and \u03b4\u2075\u2070O\u2083 values, in \u03b4\u2074\u2079O\u2083 versus \u03b4\u2075\u2070O\u2083 space, that are >10\u2030 larger than the measurements. We propose that the difference between the model and observations could be explained either by the temperature variation, Chappuis band photolysis, or a combination of the two and examine them. The isotopic fractionation associated with ozone formation increases with temperature. Our model shows that a hypothetical reduction of ~20 K in the nominal temperature profile could reproduce the observations. However, this hypothesis is not consistent with temperatures obtained by in situ measurements and NCEP Reanalysis. Photolysis of O\u2083 in the Chappuis band causes O\u2083 to be isotopically depleted, which is supported by laboratory measurements for \u00b9\u2078O\u00b9\u2078O\u00b9\u2078O but not by recent new laboratory data made at several wavelengths for \u2074\u2079O\u2083 and \u2075\u2070O\u2083. Cloud reflection can significantly enhance the photolysis rate and affect the spectral distribution of photons, which could influence the isotopic composition of ozone. Sensitivity studies that modify the isotopic composition of ozone by the above two mechanisms are presented. We conclude isotopic fractionation occurring in photolysis in the Chappuis band remains the most plausible solution to the model-observation discrepancy. Implications of our results for using the oxygen isotopic signature for constraining atmospheric chemical processes related to ozone, such as CO\u2082, nitrate, and the hydroxyl radical, are discussed.", "date": "2021-12-14", "date_type": "published", "publication": "Atmosphere", "volume": "12", "number": "12", "publisher": "MDPI", "pagerange": "Art. No. 1673", "id_number": "CaltechAUTHORS:20211214-987826000", "issn": "2073-4433", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20211214-987826000", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Ministry of Science and Technology (Taipei)", "grant_number": "108-2111-M-001-011-MY3" }, { "agency": "Academia Sinica", "grant_number": "AS-IA-109-M03" }, { "agency": "Ministry of Science and Technology (Taipei)", "grant_number": "109-2111-M-001-009-MY3" }, { "agency": "Ministry of Science and Technology (Taipei)", "grant_number": "110-2111-M-001-012-MY3" }, { "agency": "Ministry of Science and Technology (Taipei)", "grant_number": "110-2111-M-001-015-MY3" }, { "agency": "NSF", "grant_number": "AGS-1901126" }, { "agency": "NASA" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.3390/atmos12121673", "primary_object": { "basename": "atmosphere-12-01673.pdf", "url": "https://authors.library.caltech.edu/records/9txaz-ptm62/files/atmosphere-12-01673.pdf" }, "resource_type": "article", "pub_year": "2021", "author_list": "Liang, Mao-Chang; Chen, Yi-Chun; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/9rwbg-mx492", "eprint_id": 111843, "eprint_status": "archive", "datestamp": "2023-09-15 07:11:31", "lastmod": "2023-10-23 21:33:30", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Laughner-Joshua-L", "name": { "family": "Laughner", "given": "Joshua L." }, "orcid": "0000-0002-8599-4555" }, { "id": "Neu-Jessica-L", "name": { "family": "Neu", "given": "Jessica L." } }, { "id": "Schimel-David-S", "name": { "family": "Schimel", "given": "David" }, "orcid": "0000-0003-3473-8065" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Barsanti-Kelley", "name": { "family": "Barsanti", "given": "Kelley" }, "orcid": "0000-0002-6065-8643" }, { "id": "Bowman-Kevin-W", "name": { "family": "Bowman", "given": "Kevin W." }, "orcid": "0000-0002-8659-1117" }, { "id": "Chatterjee-Abhishek", "name": { "family": "Chatterjee", "given": "Abhishek" }, "orcid": "0000-0002-3680-0160" }, { "id": "Croes-Bart-E", "name": { "family": "Croes", "given": "Bart E." }, "orcid": "0000-0002-9351-0434" }, { "id": "Fitzmaurice-Helen-L", "name": { "family": "Fitzmaurice", "given": "Helen L." }, "orcid": "0000-0002-1631-5491" }, { "id": "Henze-Daven-K", "name": { "family": "Henze", "given": "Daven K." }, "orcid": "0000-0001-6431-4963" }, { "id": "Kim-Jinsol", "name": { "family": "Kim", "given": "Jinsol" } }, { "id": "Kort-Eric-A", "name": { "family": "Kort", "given": "Eric A." }, "orcid": "0000-0003-4940-7541" }, { "id": "Liu-Zhu", "name": { "family": "Liu", "given": "Zhu" }, "orcid": "0000-0002-8968-7050" }, { "id": "Miyazaki-Kazuyuki", "name": { "family": "Miyazaki", "given": "Kazuyuki" }, "orcid": "0000-0002-1466-4655" }, { "id": "Turner-Alexander-J", "name": { "family": "Turner", "given": "Alexander J." }, "orcid": "0000-0003-1406-7372" }, { "id": "Anenberg-Susan", "name": { "family": "Anenberg", "given": "Susan" }, "orcid": "0000-0002-9668-603X" }, { "id": "Avise-Jeremy", "name": { "family": "Avise", "given": "Jeremy" } }, { "id": "Cao-Hansen", "name": { "family": "Cao", "given": "Hansen" }, "orcid": "0000-0003-2713-0430" }, { "id": "Crisp-David", "name": { "family": "Crisp", "given": "David" }, "orcid": "0000-0002-4573-9998" }, { "id": "de-Gouw-Joost-A", "name": { "family": "de Gouw", "given": "Joost" }, "orcid": "0000-0002-0385-1826" }, { "id": "Eldering-Annmarie", "name": { "family": "Eldering", "given": "Annmarie" }, "orcid": "0000-0003-1080-9922" }, { "id": "Fyfe-John-C", "name": { "family": "Fyfe", "given": "John C." }, "orcid": "0000-0003-2524-0652" }, { "id": "Goldberg-Daniel-L", "name": { "family": "Goldberg", "given": "Daniel L." }, "orcid": "0000-0003-0784-3986" }, { "id": "Gurney-Kevin-R", "name": { "family": "Gurney", "given": "Kevin R." }, "orcid": "0000-0001-9218-7164" }, { "id": "Hasheminassab-Sina", "name": { "family": "Hasheminassab", "given": "Sina" } }, { "id": "Hopkins-Francesca", "name": { "family": "Hopkins", "given": "Francesca" }, "orcid": "0000-0002-6110-7675" }, { "id": "Ivey-Cesunica-E", "name": { "family": "Ivey", "given": "Cesunica E." }, "orcid": "0000-0002-4740-2627" }, { "id": "Jones-Dylan-B-A", "name": { "family": "Jones", "given": "Dylan B. A." } }, { "id": "Liu-Junjie", "name": { "family": "Liu", "given": "Junjie" }, "orcid": "0000-0002-7184-6594" }, { "id": "Lovenduski-Nicole-S", "name": { "family": "Lovenduski", "given": "Nicole S." }, "orcid": "0000-0001-5893-1009" }, { "id": "Martin-Randall-V", "name": { "family": "Martin", "given": "Randall V." }, "orcid": "0000-0003-2632-8402" }, { "id": "McKinley-Galen-A", "name": { "family": "McKinley", "given": "Galen A." }, "orcid": "0000-0002-4072-9221" }, { "id": "Ott-Lesley", "name": { "family": "Ott", "given": "Lesley" }, "orcid": "0000-0002-0035-9625" }, { "id": "Poulter-Benjamin", "name": { "family": "Poulter", "given": "Benjamin" }, "orcid": "0000-0002-9493-8600" }, { "id": "Ru-Muye", "name": { "family": "Ru", "given": "Muye" }, "orcid": "0000-0003-3252-1030" }, { "id": "Sander-Stanley-P", "name": { "family": "Sander", "given": "Stanley P." }, "orcid": "0000-0003-1424-3620" }, { "id": "Swart-Neil", "name": { "family": "Swart", "given": "Neil" }, "orcid": "0000-0002-8200-6187" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Zeng-Zhao-Cheng", "name": { "family": "Zeng", "given": "Zhao-Cheng" }, "orcid": "0000-0002-0008-6508" } ] }, "title": "Societal shifts due to COVID-19 reveal large-scale complexities and feedbacks between atmospheric chemistry and climate change", "ispublished": "pub", "full_text_status": "public", "keywords": "COVID-19; air quality; greenhouse gases; earth system; mitigation", "note": "\u00a9 2021 the Author(s). Published by PNAS. This open access article is distributed under Creative Commons Attribution-NonCommercial-NoDerivatives License 4.0 (CC BY-NC-ND). \n\nEdited by Akkihebbal R. Ravishankara, Colorado State University, Fort Collins, CO, and approved September 29, 2021 (received for review June 10, 2021). \n\nWe thank the Keck Institute for Space Studies for organizing and supporting the study \"COVID-19: Identifying Unique Opportunities for Earth System Science\" that led to the writing of this manuscript. We also acknowledge the use of data from the Port of Oakland and Port of LA website, Apple mobility data, and US EIA electricity-use data. We also thank Charles Carter for his artwork in Fig. 1. We thank the TCCON science team for their effort in providing data. Support for operation of the Park Falls TCCON site is provided by NASA. The Lauder TCCON programme is funded by NIWA (National Institute of Water & Atmospheric Research Ltd.) through Aotearoa New Zealand's Ministry of Business, Innovation and Employment's Strategic Science Investment Fund. The views expressed in this manuscript are solely those of the authors and do not necessarily reflect those of the South Coast Air Quality Management District. A portion of this research was carried out at the Jet Propulsion Laboratory (JPL), California Institute of Technology, under a contract with NASA. This work was supported by NASA Grant NNX17AE15G (to J.L.L. and P.O.W.), NASA Carbon Monitoring System Grant 80NSSC20K0006 (to A.C.), NASA Grant 80NSSC18K0689 (to D.K.H. and H.C.), NASA Aura Science Team Program 19-AURAST19-0044 (to K.M. and K.W.B.), NASA Grant 80NSSC20K1122 (to D.L.G. and S.A.), NASA Grant 80NSSC21K0508 (to R.V.M.), NSF RAPID Grant 2030049 (to K.B.), NSF Grants OCE-1752724 and OCE-1948664 (to N.S.L.), and NSF Grant OCE-1948624 (to G.A.M.). A.J.T. was supported as a Miller Fellow with the Miller Institute for Basic Research in Science at the University of California Berkeley. K.R.G. was supported by Northern Arizona University startup funds. C.E.I. was supported by the University of California Institute of Transportation Studies. S.P.S. and Z.-C.Z. were supported by the California Air Resources Board, NASA Science Mission Directorate/Earth Science Division, and JPL Earth Science and Technology Directorate. Y.L.Y. was supported in part by JPL OCO-2 Grant JPL.1613918 (to the California Institute of Technology). J.L. was supported by the NASA OCO science team program. \n\nData Availability: GEOS-Chem Model Output data have been deposited in Zenodo (https://zenodo.org/record/4849416) (71). Publicly available datasets are listed along with data generated from this study and stored in public-facing repositories in SI Appendix, Table S1. Emissions data for Figs. 3 and 9 are given in SI Appendix, Table S2. Data for the OPE values in Fig. 7 are given in SI Appendix, Table S4. Emissions and OPE data are also included as Datasets S1 and S2. In addition, previously published data (1, 2, 13, 25, 29\u201331, 35, 72\u201384) were used for this work. \n\nAuthor contributions: J.L.L., K.B., K.W.B., A.C., B.E.C., H.L.F., D.K.H., J.K., E.A.K., Z.L., K.M., A.J.T., S.A., J.A., H.C., D.C., J.d.G., A.E., J.C.F., D.L.G., K.R.G., S.H., F.H., C.E.I., D.B.A.J., J.L., N.S.L., R.V.M., G.A.M., L.O., B.P., M.R., S.P.S., N.S., Y.L.Y., and Z.-C.Z. performed research; J.L.N., D.S., and P.O.W. designed research; J.L.L., J.L.N., D.S., P.O.W., K.B., K.W.B., A.C., B.E.C., H.L.F., D.K.H., J.K., E.A.K., Z.L., K.M., A.J.T., S.A., J.A., H.C., D.C., J.d.G., A.E., J.C.F., D.L.G., K.R.G., S.H., F.H., C.E.I., D.B.A.J., J.L., N.S.L., R.V.M., G.A.M., L.O., B.P., M.R., S.P.S., N.S., Y.L.Y., and Z.-C.Z. analyzed data; J.L.L., J.L.N., D.S., and P.O.W. wrote the paper; and K.B., K.W.B., A.C., B.E.C., H.L.F., D.K.H., J.K., E.A.K., Z.L., K.M., A.J.T., S.A., J.A., H.C., D.C., J.d.G., A.E., J.C.F., D.L.G., K.R.G., S.H., F.H., C.E.I., D.B.A.J., J.L., N.S.L., R.V.M., G.A.M., L.O., B.P., M.R., S.P.S., N.S., Y.L.Y., and Z.-C.Z. edited and approved the manuscript draft. \n\nThe authors declare no competing interest. \n\nThis article is a PNAS Direct Submission. \n\nThis article contains supporting information online at https://www.pnas.org/lookup/suppl/doi:10.1073/pnas.2109481118/-/DCSupplemental.\n\nPublished - e2109481118.full.pdf
Supplemental Material - pnas.2109481118.sapp.pdf
Supplemental Material - pnas.2109481118.sd01.docx
Supplemental Material - pnas.2109481118.sd01.xlsx
Supplemental Material - pnas.2109481118.sd02.xlsx
", "abstract": "The COVID-19 global pandemic and associated government lockdowns dramatically altered human activity, providing a window into how changes in individual behavior, enacted en masse, impact atmospheric composition. The resulting reductions in anthropogenic activity represent an unprecedented event that yields a glimpse into a future where emissions to the atmosphere are reduced. Furthermore, the abrupt reduction in emissions during the lockdown periods led to clearly observable changes in atmospheric composition, which provide direct insight into feedbacks between the Earth system and human activity. While air pollutants and greenhouse gases share many common anthropogenic sources, there is a sharp difference in the response of their atmospheric concentrations to COVID-19 emissions changes, due in large part to their different lifetimes. Here, we discuss several key takeaways from modeling and observational studies. First, despite dramatic declines in mobility and associated vehicular emissions, the atmospheric growth rates of greenhouse gases were not slowed, in part due to decreased ocean uptake of CO\u2082 and a likely increase in CH\u2084 lifetime from reduced NO_x emissions. Second, the response of O\u2083 to decreased NO_x emissions showed significant spatial and temporal variability, due to differing chemical regimes around the world. Finally, the overall response of atmospheric composition to emissions changes is heavily modulated by factors including carbon-cycle feedbacks to CH\u2084 and CO\u2082, background pollutant levels, the timing and location of emissions changes, and climate feedbacks on air quality, such as wildfires and the ozone climate penalty.", "date": "2021-11-16", "date_type": "published", "publication": "Proceedings of the National Academy of Sciences", "volume": "118", "number": "46", "publisher": "National Academy of Sciences", "pagerange": "Art. No. e2109481118", "id_number": "CaltechAUTHORS:20211111-200602979", "issn": "0027-8424", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20211111-200602979", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA/JPL/Caltech" }, { "agency": "NASA", "grant_number": "NNX17AE15G" }, { "agency": "NASA", "grant_number": "80NSSC20K0006" }, { "agency": "NASA", "grant_number": "80NSSC18K0689" }, { "agency": "NASA", "grant_number": "19-AURAST19-0044" }, { "agency": "NASA", "grant_number": "80NSSC20K1122" }, { "agency": "NASA", "grant_number": "80NSSC21K0508" }, { "agency": "NSF", "grant_number": "2030049" }, { "agency": "NSF", "grant_number": "OCE-1752724" }, { "agency": "NSF", "grant_number": "OCE-1948664" }, { "agency": "NSF", "grant_number": "OCE-1948624" }, { "agency": "Miller Institute for Basic Research in Science" }, { "agency": "Northern Arizona University" }, { "agency": "University of California" }, { "agency": "California Air Resources Board" }, { "agency": "JPL", "grant_number": "JPL.1613918" } ] }, "local_group": { "items": [ { "id": "COVID-19" }, { "id": "Keck-Institute-for-Space-Studies" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1073/pnas.2109481118", "pmcid": "PMC8609622", "primary_object": { "basename": "e2109481118.full.pdf", "url": "https://authors.library.caltech.edu/records/9rwbg-mx492/files/e2109481118.full.pdf" }, "related_objects": [ { "basename": "pnas.2109481118.sapp.pdf", "url": "https://authors.library.caltech.edu/records/9rwbg-mx492/files/pnas.2109481118.sapp.pdf" }, { "basename": "pnas.2109481118.sd01.docx", "url": "https://authors.library.caltech.edu/records/9rwbg-mx492/files/pnas.2109481118.sd01.docx" }, { "basename": "pnas.2109481118.sd01.xlsx", "url": "https://authors.library.caltech.edu/records/9rwbg-mx492/files/pnas.2109481118.sd01.xlsx" }, { "basename": "pnas.2109481118.sd02.xlsx", "url": "https://authors.library.caltech.edu/records/9rwbg-mx492/files/pnas.2109481118.sd02.xlsx" } ], "resource_type": "article", "pub_year": "2021", "author_list": "Laughner, Joshua L.; Neu, Jessica L.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/6fx62-bf613", "eprint_id": 112348, "eprint_status": "archive", "datestamp": "2023-08-22 11:56:10", "lastmod": "2023-10-23 19:42:21", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Luo-Yangcheng", "name": { "family": "Luo", "given": "Y." }, "orcid": "0000-0003-0983-3650" }, { "id": "Mischna-Michael-A", "name": { "family": "Mischna", "given": "M. A." }, "orcid": "0000-0002-8022-5319" }, { "id": "Lin-John-C", "name": { "family": "Lin", "given": "J. C." }, "orcid": "0000-0003-2794-184X" }, { "id": "Fasoli-Benjamin", "name": { "family": "Fasoli", "given": "B." }, "orcid": "0000-0001-7372-2176" }, { "id": "Cai-X", "name": { "family": "Cai", "given": "X." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Y. L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Mars Methane Sources in Northwestern Gale Crater Inferred From Back Trajectory Modeling", "ispublished": "pub", "full_text_status": "public", "keywords": "Mars; methane; back trajectory; MSL; TLS; TGO; General Earth and Planetary Sciences; Environmental Science (miscellaneous)", "note": "\u00a9 2021 The Authors. Earth and Space Science published by Wiley Periodicals LLC on behalf of American Geophysical Union. This is an open access article under the terms of the Creative Commons Attribution-NonCommercial-NoDerivs License, which permits use and distribution in any medium, provided the original work is properly cited, the use is non-commercial and no modifications or adaptations are made. \n\nIssue Online: 15 November 2021. Version of Record online: 15 November 2021. Accepted manuscript online: 04 November 2021. Manuscript accepted: 27 October 2021. Manuscript revised: 26 October 2021. Manuscript received: 11 July 2021. \n\nA portion of this research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under contract with NASA (80NM0018D0004). Y. L. Yung acknowledges the President's and Director's Research and Development Fund and the support from the Virtual Planetary Laboratory at the University of Washington that is funded via NASA Astrobiology Program Grant No. 80NSSC18K0829. Resources supporting this work were provided by the NASA High-End Computing (HEC) Program through the NASA Advanced Supercomputing (NAS) Division at Ames Research Center. \n\nData Availability Statement\nA file that lists all the relevant conditions and parameters used in the MarsWRF simulations can be found at the CaltechDATA repository via https://doi.org/10.22002/D1.2027 (Mischna, 2021). The original STILT model is available at its website https://uataq.github.io/stilt/#/ (Lin et al., 2020). A list of modifications to the original STILT model based on the conditions of Mars can be found at the CaltechDATA repository via https://doi.org/10.22002/D1.2026 (Luo et al., 2021a). The NetCDF formatted STILT footprint files that are used to generate Figures 3-5 in the main text and Figures S5\u2013S10 in Supporting Information S1 are available at the CaltechDATA repository via https://doi.org/10.22002/D1.2025 (Luo et al., 2021b).\n\nPublished - 2021EA001915.pdf
Supplemental Material - 2021ea001915-sup-0001-supporting_information_si-s01.pdf
", "abstract": "During its first seven years of operation, the Sample Analysis at Mars Tunable Laser Spectrometer (TLS) on board the Curiosity rover has detected seven methane spikes above a low background abundance in Gale crater. The methane spikes are likely sourced by surface emission within or around Gale crater. Here, we use inverse Lagrangian modeling techniques to identify upstream emission regions on the Martian surface for these methane spikes at an unprecedented spatial resolution. Inside Gale crater, the northwestern crater floor casts the strongest influence on the detections. Outside Gale crater, the upstream regions common to all the methane spikes extend toward the north. The contrasting results from two consecutive TLS methane measurements performed on the same sol point to an active emission site to the west or the southwest of the Curiosity rover on the northwestern crater floor. The observed spike magnitude and frequency also favor emission sites on the northwestern crater floor, unless there are fast methane removal mechanisms at work, or either the methane spikes of TLS or the non-detections of ExoMars Trace Gas Orbiter cannot be trusted.", "date": "2021-11-04", "date_type": "published", "publication": "Earth and Space Science", "volume": "8", "number": "11", "publisher": "American Geophysical Union", "pagerange": "Art. No. e2021EA001915", "id_number": "CaltechAUTHORS:20211209-231120000", "issn": "2333-5084", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20211209-231120000", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA/JPL/Caltech", "grant_number": "80NM0018D0004" }, { "agency": "JPL President and Director's Fund" }, { "agency": "NASA", "grant_number": "80NSSC18K0829" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2021ea001915", "primary_object": { "basename": "2021EA001915.pdf", "url": "https://authors.library.caltech.edu/records/6fx62-bf613/files/2021EA001915.pdf" }, "related_objects": [ { "basename": "2021ea001915-sup-0001-supporting_information_si-s01.pdf", "url": "https://authors.library.caltech.edu/records/6fx62-bf613/files/2021ea001915-sup-0001-supporting_information_si-s01.pdf" } ], "resource_type": "article", "pub_year": "2021", "author_list": "Luo, Y.; Mischna, M. A.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/asw2y-d9h79", "eprint_id": 110790, "eprint_status": "archive", "datestamp": "2023-08-22 11:53:41", "lastmod": "2023-10-23 19:52:32", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Parkinson-Christopher-D", "name": { "family": "Parkinson", "given": "C. D." }, "orcid": "0000-0002-5722-2224" }, { "id": "Bougher-S-W", "name": { "family": "Bougher", "given": "S. W." } }, { "id": "Mills-F-P", "name": { "family": "Mills", "given": "F. P." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Y. L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Brecht-A", "name": { "family": "Brecht", "given": "A." } }, { "id": "Shields-D", "name": { "family": "Shields", "given": "D." } }, { "id": "Liemohn-M", "name": { "family": "Liemohn", "given": "M." } } ] }, "title": "Modeling of observations of the OH nightglow in the venusian mesosphere", "ispublished": "pub", "full_text_status": "public", "keywords": "Venus; Chemistry and dynamics; Hydroxyl; Nightglow; Mesosphere", "note": "\u00a9 2021 Published by Elsevier. \n\nReceived 25 September 2020, Revised 24 May 2021, Accepted 7 June 2021, Available online 11 June 2021. \n\nThis research was partially supported by NASA Grant NNX16AN03G to the Space Science Institute (SSI). We thank A. Garcia-Mu\u00f1oz for reviewing the document and providing insightful comments. Y. L. Yung was supported in part by the University of Washington. This is University of Texas Center for Planetary Systems Habitability Contribution #0026 (F. Mills). \n\nDeclaration of Competing Interest: None.\n\nSupplemental Material - 1-s2.0-S0019103521002499-mmc1.docx
", "abstract": "Venus airglow emissions have been unambiguously detected in the wavelength ranges of 1.40\u20131.49 and 2.6\u20133.14 \u03bcm in limb observations by the Visible and Infrared Thermal Imaging Spectrometer (VIRTIS) onboard the Venus Express (VEx) spacecraft and are attributed to the OH(2\u20130) and OH(1\u20130) Meinel band transitions. The integrated (limb slant path) emission rates for these bands were measured by Piccioni et al. (2008). \n\nPhotochemical (Caltech/JPL KINETICS) and global circulation (Venus Thermospheric General Circulation Model - VTGCM) model calculations suggest the observed OH emission is produced primarily via the Bates-Nicolet mechanism, as on the Earth, although Venus' background atmosphere is different than that of the Earth, but the modeled contribution of the HO\u2082 + O \u2192 OH(v) + O\u2082 reaction increases in the lower portion of the OH airglow layer. An overall difference of ~2 km in the peak heights of the OH(1\u20130) and OH(2\u20130) layers is seen in both the KINETICS and VTGCM simulations as a result of this change in the relative importance of H + O\u2083 \u2192 OH(v) + O\u2082 versus HO\u2082 + O \u2192 OH(v) + O\u2082 reactions with altitude. \n\nFirst time 3-D simulations of the OH \u0394v = 1 nightglow limb slant emission calculate a peak intensity of ~0.6 \u00b1 0.3 MegaRayleighs at ~102 km altitude, an intensity that is consistent with Venus Express VIRTIS observations (G\u00e9rard et al. 2010; Soret et al. 2010, 2012) and KINETICS results. Soret et al. (2010) reported the intensity of the peak OH airglow increased from 0.30 to 0.40 MR from dusk to dawn but noted the observations used are not uniformly distributed and the observed emission is extremely variable, so a more detailed assessment of the observations was not possible. Our simulations show a decrease in the average OH(1\u20130) emission is symmetric about the midnight meridian, but the simulations find an asymmetric decrease from the equator to the poles. Consideration of transport and chemical lifetimes suggests modeling of OH above ~96 km requires explicit description of transport and vibrational-state-dependent chemistry.", "date": "2021-11-01", "date_type": "published", "publication": "Icarus", "volume": "368", "publisher": "Elsevier", "pagerange": "Art. No. 114580", "id_number": "CaltechAUTHORS:20210908-225043680", "issn": "0019-1035", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210908-225043680", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NNX16AN03G" }, { "agency": "University of Washington" } ] }, "other_numbering_system": { "items": [ { "id": "0026", "name": "Texas Center for Planetary Systems Habitability" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/j.icarus.2021.114580", "primary_object": { "basename": "1-s2.0-S0019103521002499-mmc1.docx", "url": "https://authors.library.caltech.edu/records/asw2y-d9h79/files/1-s2.0-S0019103521002499-mmc1.docx" }, "resource_type": "article", "pub_year": "2021", "author_list": "Parkinson, C. D.; Bougher, S. W.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/3c1nv-w2s45", "eprint_id": 110234, "eprint_status": "archive", "datestamp": "2023-08-20 03:50:40", "lastmod": "2023-10-23 19:31:32", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Campbell-Elliott", "name": { "family": "Campbell", "given": "Elliott" } }, { "id": "Fisher-Joshua-B", "name": { "family": "Fisher", "given": "Joshua" } }, { "id": "Kuai-Le", "name": { "family": "Kuai", "given": "Le" }, "orcid": "0000-0001-6406-1150" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Baker-Ian-T", "name": { "family": "Baker", "given": "Ian" } }, { "id": "Berry-Joseph-A", "name": { "family": "Berry", "given": "Joe" }, "orcid": "0000-0002-5849-6438" }, { "id": "Bowman-Kevin-W", "name": { "family": "Bowman", "given": "Kevin" }, "orcid": "0000-0002-8659-1117" }, { "id": "Commane-R\u00f3is\u00edn", "name": { "family": "Commane", "given": "R\u00f3is\u00edn" }, "orcid": "0000-0003-1373-1550" }, { "id": "Frankenberg-C", "name": { "family": "Frankenberg", "given": "Christian" }, "orcid": "0000-0002-0546-5857" }, { "id": "Liu-Junjie", "name": { "family": "Liu", "given": "Junjie" }, "orcid": "0000-0002-7184-6594" }, { "id": "Magney-Troy-S", "name": { "family": "Magney", "given": "Troy" }, "orcid": "0000-0002-9033-0024" }, { "id": "Marshall-Julia", "name": { "family": "Marshall", "given": "Julia" } }, { "id": "Miller-Charles-E", "name": { "family": "Miller", "given": "Charles E." }, "orcid": "0000-0002-9380-4838" }, { "id": "Noone-David-C", "name": { "family": "Noone", "given": "David" } }, { "id": "Parazoo-Nicholas-C", "name": { "family": "Parazoo", "given": "Nicholas" }, "orcid": "0000-0002-4424-7780" }, { "id": "Ryu-Youngryel", "name": { "family": "Ryu", "given": "Youngryel" }, "orcid": "0000-0001-6238-2479" }, { "id": "Saleska-Scott", "name": { "family": "Saleska", "given": "Scott" } }, { "id": "Schimel-David-S", "name": { "family": "Schimel", "given": "David" }, "orcid": "0000-0003-3473-8065" }, { "id": "Seibt-Ulrike", "name": { "family": "Seibt", "given": "Ulrike" } }, { "id": "Stinecipher-James", "name": { "family": "Stinecipher", "given": "James" } }, { "id": "Sun-Wu", "name": { "family": "Sun", "given": "Wu" } }, { "id": "Sun-Ying", "name": { "family": "Sun", "given": "Ying" }, "orcid": "0000-0002-9819-1241" }, { "id": "Toon-Geoffrey-C", "name": { "family": "Toon", "given": "Geoffrey" }, "orcid": "0000-0003-4174-7541" }, { "id": "Wang-Yutang", "name": { "family": "Wang", "given": "Yutang" } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul" }, "orcid": "0000-0002-6126-3854" }, { "id": "Whelan-Mary-E", "name": { "family": "Whelan", "given": "Mary E." } }, { "id": "Worden-John-R", "name": { "family": "Worden", "given": "John" }, "orcid": "0000-0003-0257-9549" }, { "id": "Zeng-Zhao-Cheng", "name": { "family": "Zeng", "given": "Zhao-Cheng" }, "orcid": "0000-0002-0008-6508" } ] }, "title": "Detecting Climate-Carbon Feedbacks: Next-Generation Approach for Space-Based Integration of OCS, CO\u2082, and SIF", "ispublished": "unpub", "full_text_status": "public", "note": "\u00a9 June 26, 2021 Keck Institute for Space Studies.\n\nAccepted Version - Carbon-Climate-Final.pdf
", "abstract": "Photosynthesis is a keystone process for the Earth system. The emergence of photosynthesis transformed Earth's geologic, geochemical, and biologic evolution, and today, virtually all life on Earth depends on this process as a direct or indirect food source. Photosynthesis controls a fundamental link between the global carbon, water, and energy cycles, which underlies central scientific mysteries of the Earth system. In particular, post-industrial growth\nin global photosynthesis is responsible for one of the largest and most uncertain feedbacks to anthropogenic climate change. \n\nDespite its importance, photosynthesis cannot be measured directly at scales larger than the leaf. Historically, measurements of CO\u2082 gas exchange are suitable for leaf chambers, but at larger scales, this technique is confounded by CO\u2082 emissions from soils. Theories of global photosynthesis are largely in the realm of computer simulations. Thus, measurement technology limits our ability to pursue questions that are essential to understanding the processes governing the Earth system and impacting our future. \n\nTo confront this key scientific challenge, the workshop \"Next-Generation Approach for Detecting Climate\u2013Carbon Feedbacks: Space-Based Integration of OCS, CO\u2082, and SIF\"\nassembled a multi-disciplinary team to conceive a new integrated technique for measuring photosynthesis at regional to global scales. The participants merged perspectives from the fields of ecology, biogeochemistry, atmospheric chemistry, and space science to focus on how a rapidly emerging technique with carbonyl sulfide sensors (OCS or COS) could be integrated with existing CO\u2082 and satellite observations of solar-induced chlorophyll fluorescence (SIF) platforms. \n\nThe workshop discussions leveraged recent findings from atmospheric OCS observations and plant gas exchange studies that reveal a robust relationship between regional variation in photosynthesis and atmospheric variation in OCS. Plant leaves consume atmospheric OCS gas through a one-way hydration sink, which is controlled by stomatal conductance that is also a primary control on photosynthesis. Atmospheric OCS observations, such as the satellite detection of a massive depletion in OCS over the Amazon, can then provide a measurement-based estimate of photosynthesis. \n\nThese OCS findings were analyzed within the context of recent breakthroughs from spaceborne SIF analysis. SIF platforms record the electromagnetic energy released from plant leaves during photosynthesis. Strong correlations between SIF and photosynthesis suggest an alternative\nmeans of assessing global photosynthesis from space. \n\nThe key result of this workshop is that these alternative methods fill critical, yet different, methodological gaps, suggesting the need for a unified, space-based, photosynthesis observation platform. First, the highly complementary temporal and spatial scales of SIF analysis provide instantaneous, spatially resolved data and OCS provides spatially and temporally integrated data. Second, the independent photosynthesis processes that need to be constrained include the biochemical SIF constraint and stomatal conductance OCS constraint. Third, the Amazon basin is identified as an ideal domain where the temporally integrated OCS analysis could confront cloud contamination problems of alternative approaches. \n\nThese outcomes has been used to develop a roadmap for near-, mid-, and long-term activities to achieve this vision for a unified global photosynthesis observing system. Proof-of-concept studies, including an airborne field experiment in the Amazon and an observing system simulation experiment, will provide critical evidence for the proposed satellite observations. The workshop team will collaborate on perspective articles in diverse disciplinary journals and develop a research coordinating network to communicate this new approach to the broad community of scientists and technologists who would be impacted by enabling a large-scale understanding of global photosynthesis.", "date": "2021-08-13", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechAUTHORS:20210813-163903875", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210813-163903875", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Keck Institute for Space Studies (KISS)" } ] }, "local_group": { "items": [ { "id": "Keck-Institute-for-Space-Studies" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.7907/81y6-1195", "primary_object": { "basename": "Carbon-Climate-Final.pdf", "url": "https://authors.library.caltech.edu/records/3c1nv-w2s45/files/Carbon-Climate-Final.pdf" }, "resource_type": "monograph", "pub_year": "2021", "author_list": "Campbell, Elliott; Fisher, Joshua; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/r7rsd-a7a17", "eprint_id": 110107, "eprint_status": "archive", "datestamp": "2023-08-22 10:34:52", "lastmod": "2023-10-23 17:17:09", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Luo-Yangcheng", "name": { "family": "Luo", "given": "Y." }, "orcid": "0000-0003-0983-3650" }, { "id": "Mischna-Michael-A", "name": { "family": "Mischna", "given": "M. A." }, "orcid": "0000-0002-8022-5319" }, { "id": "Lin-John-C", "name": { "family": "Lin", "given": "J. C." }, "orcid": "0000-0003-2794-184X" }, { "id": "Fasoli-Benjamin", "name": { "family": "Fasoli", "given": "B." }, "orcid": "0000-0001-7372-2176" }, { "id": "Cai-Xiang", "name": { "family": "Cai", "given": "X." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Y. L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Mars Methane Sources in Northwestern Gale Crater Inferred from Back-Trajectory Modeling", "ispublished": "unpub", "full_text_status": "public", "keywords": "Atmospheric Sciences, Atmospheric Sciences / Numerical Modelling, Planetology / Planets, Planetology, Planetology / Planetary Atmospheres", "note": "The copyright holder for this preprint is the author/funder. \n\nPublished Online: Tue, 20 Jul 2021. \n\nA portion of this research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under contract with NASA. Government sponsorship acknowledged. Y. L. Y acknowledges the President's and Director's Research and Development Fund and the support from the Virtual Planetary Laboratory at the University of Washington that is funded via NASA Astrobiology Program Grant No. 80NSSC18K0829. Resources supporting this work were\nprovided by the NASA High-End Computing (HEC) Program through the NASA Advanced Supercomputing (NAS) Division at Ames Research Center. \n\nA file that lists all the relevant conditions and parameters used in the MarsWRF simulations can be found at the CaltechDATA reposity via https://doi.org/10.22002/D1.2026. The original STILT model is available at its website https://uataq.github.io/stilt/#/. A list of modifications to\nthe original STILT model based on the conditions of Mars can be found at the CaltechDATA repository via https://doi.org/10.22002/D1.2026. The STILT footprint files used to generate Figure 3\u20135 in this study are available at the CaltechDATA repository via https://doi.org/10.22002/D1.2025.\n\nSubmitted - essoar.10507550.1.pdf
", "abstract": "During its five years of operation as of 2017, the Sample Analysis at Mars (SAM) Tunable Laser Spectrometer (TLS) on board the Curiosity rover has detected six methane spikes above a low background abundance in Gale crater. The methane spikes are likely sourced by nearby emission from the surface. Here we use inverse Lagrangian modeling techniques to identify upstream emission regions on the Martian surface for these methane spikes at unprecedented spatial resolutions. Inside Gale crater, the northwestern crater floor casts the strongest influence on the detections. Outside Gale crater, the upstream regions extend towards the north. The contrasting results from two consecutive TLS methane measurements point to an active emission site to the west and the southwest of the Curiosity rover on the northwestern crater floor. The observed spike magnitude and frequency also favor emission sites on the northwestern crater floor, unless there are fast methane removal mechanisms at work, or either the TLS methane spikes or the Trace Gas Orbiter (TGO) non-detections can not be trusted.", "date": "2021-08-02", "date_type": "published", "publisher": "Caltech Library", "id_number": "CaltechAUTHORS:20210730-184542683", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210730-184542683", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA/JPL/Caltech" }, { "agency": "JPL President and Director's Fund" }, { "agency": "NASA", "grant_number": "80NSSC18K0829" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "primary_object": { "basename": "essoar.10507550.1.pdf", "url": "https://authors.library.caltech.edu/records/r7rsd-a7a17/files/essoar.10507550.1.pdf" }, "resource_type": "monograph", "pub_year": "2021", "author_list": "Luo, Y.; Mischna, M. A.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/8ttxj-j6722", "eprint_id": 110680, "eprint_status": "archive", "datestamp": "2023-08-22 10:44:58", "lastmod": "2023-10-23 19:48:09", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Adams-Danica-J", "name": { "family": "Adams", "given": "Danica" }, "orcid": "0000-0001-9897-9680" }, { "id": "Luo-Yangcheng", "name": { "family": "Luo", "given": "Yangcheng" } }, { "id": "Wong-Michael-L", "name": { "family": "Wong", "given": "Michael L." } }, { "id": "Dunn-Patrick", "name": { "family": "Dunn", "given": "Patrick" } }, { "id": "Christensen-Madeline", "name": { "family": "Christensen", "given": "Madeline" } }, { "id": "Dong-Chuanfei", "name": { "family": "Dong", "given": "Chuanfei" }, "orcid": "0000-0002-8990-094X" }, { "id": "Hu-Renyu", "name": { "family": "Hu", "given": "Renyu" }, "orcid": "0000-0003-2215-8485" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk" }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Nitrogen Fixation at Early Mars", "ispublished": "pub", "full_text_status": "public", "keywords": "Nitrogen fixation; Early Mars; Astrobiology; Nitrate.", "note": "\u00a9 2021, Mary Ann Liebert, Inc., publishers. \n\nSubmitted 7 April 2020; Accepted 26 April 2021. Online Ahead of Print: July 30, 2021. \n\nWe thank Pin Chen, Armin Kleinboehl, Robin Wordsworth, David Romps, Stuart Bartlett, and Rob Lillis for useful discussions. \n\nD.A. was supported by NASA's FINESST program under Proposal Number 80NSSC19K1548. M.L.W. was supported by NASA's Virtual Planetary Laboratory under NASA Astrobiology Institute Cooperative Agreement Number NNA13AA93A and Grant Number 80NSSC18K0829. C.D. was supported by NASA's Habitable Worlds program under Proposal Number 80NSSC18K0288. The research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration (80NM0018D0004). This research was initiated under and partially supported by a NASA Habitable Worlds grant (#NNN130466T, later changed to #80NM0018F0612) to Pl R.H. and Co-I Y.L.Y. \n\nNo competing financial interests exist.\n\nPublished - ast.2020.2273_pub.pdf
Supplemental Material - Supp_AppS1.doc
Supplemental Material - Supp_AppS2.doc
Supplemental Material - Supp_AppS3.doc
Supplemental Material - Supp_AppS4.doc
", "abstract": "The Mars Science Laboratory (MSL) recently discovered nitrates in Gale Crater (e.g., Stern et al., 2015; Sutter et al., 2017). One possible mechanism for ancient nitrate deposition on Mars is through HNOx formation and rain out in the atmosphere, for which lightning-induced NO is likely the fundamental source. This study investigates nitrogen (N\u2082) fixation in early Mars' atmosphere, with implications for early Mars' habitability. We consider a 1 bar atmosphere of background CO\u2082, with abundance of N\u2082, hydrogen, and methane varied from 1% to 10% to explore a swath of potential early Mars climates. We derive lightning-induced thermochemical equilibrium fluxes of NO and HCN by coupling the lightning-rate parametrization from the study of Romps et al. (2014) with chemical equilibrium with applications, and we use a Geant4 simulation platform to estimate the effect of solar energetic particle events. These fluxes are used as input into KINETICS, the Caltech/JPL coupled photochemistry and transport code, which models the chemistry of 50 species linked by 495 reactions to derive rain-out fluxes of HNOx and HCN. We compute equilibrium concentrations of cyanide and nitrate in a putative northern ocean at early Mars, assuming hydrothermal vent circulation and photoreduction act as the dominant loss mechanisms. We find average oceanic concentrations of \u223c0.1\u20132\u2009nM nitrate and \u223c0.01\u20132\u2009mM cyanide. HCN is critical for protein synthesis at concentrations >0.01\u2009M (e.g., Holm and Neubeck, 2009), and our result is astrobiologically significant if secondary local concentration mechanisms occurred. Nitrates may act as high-potential electron acceptors for early metabolisms, although the minimum concentration required is unknown. Our study derives concentrations that will be useful for future laboratory studies to investigate the habitability at early Mars. The aqueous nitrate concentrations correspond to surface nitrate precipitates of \u223c1\u20138\u2009\u00d7\u200910\u207b\u2074 wt % that may have formed after the evaporation of surface waters, and these values roughly agree with recent MSL measurements.", "date": "2021-08", "date_type": "published", "publication": "Astrobiology", "volume": "21", "number": "8", "publisher": "Mary Ann Liebert", "pagerange": "968-980", "id_number": "CaltechAUTHORS:20210831-224223138", "issn": "1531-1074", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210831-224223138", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA Earth and Space Science and Technology Fellowship", "grant_number": "80NSSC19K1548" }, { "agency": "NASA", "grant_number": "NNA13AA93A" }, { "agency": "NASA", "grant_number": "80NSSC18K0829" }, { "agency": "NASA", "grant_number": "80NSSC18K0288" }, { "agency": "NASA", "grant_number": "80NM0018D0004" }, { "agency": "NASA", "grant_number": "NNN130466T" }, { "agency": "NASA", "grant_number": "80NM0018F0612" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1089/ast.2020.2273", "primary_object": { "basename": "Supp_AppS1.doc", "url": "https://authors.library.caltech.edu/records/8ttxj-j6722/files/Supp_AppS1.doc" }, "related_objects": [ { "basename": "Supp_AppS2.doc", "url": "https://authors.library.caltech.edu/records/8ttxj-j6722/files/Supp_AppS2.doc" }, { "basename": "Supp_AppS3.doc", "url": "https://authors.library.caltech.edu/records/8ttxj-j6722/files/Supp_AppS3.doc" }, { "basename": "Supp_AppS4.doc", "url": "https://authors.library.caltech.edu/records/8ttxj-j6722/files/Supp_AppS4.doc" }, { "basename": "ast.2020.2273_pub.pdf", "url": "https://authors.library.caltech.edu/records/8ttxj-j6722/files/ast.2020.2273_pub.pdf" } ], "resource_type": "article", "pub_year": "2021", "author_list": "Adams, Danica; Luo, Yangcheng; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/dxhed-gjf51", "eprint_id": 109562, "eprint_status": "archive", "datestamp": "2023-08-22 10:16:37", "lastmod": "2023-10-23 18:02:53", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Yang-Jiani", "name": { "family": "Yang", "given": "Jiani" }, "orcid": "0000-0003-0037-2413" }, { "id": "Wen-Yifan", "name": { "family": "Wen", "given": "Yifan" }, "orcid": "0000-0003-1876-7990" }, { "id": "Wang-Yuan", "name": { "family": "Wang", "given": "Yuan" }, "orcid": "0000-0001-6657-8401" }, { "id": "Zhang-Shaojun", "name": { "family": "Zhang", "given": "Shaojun" }, "orcid": "0000-0002-2176-6174" }, { "id": "Pinto-Joseph-P", "name": { "family": "Pinto", "given": "Joseph P." }, "orcid": "0000-0001-5639-8458" }, { "id": "Pennington-Elyse-A", "name": { "family": "Pennington", "given": "Elyse A." }, "orcid": "0000-0003-1736-2342" }, { "id": "Wang-Zhou", "name": { "family": "Wang", "given": "Zhou" } }, { "id": "Wu-Ye", "name": { "family": "Wu", "given": "Ye" }, "orcid": "0000-0002-9928-1177" }, { "id": "Sander-Stanley-P", "name": { "family": "Sander", "given": "Stanley P." }, "orcid": "0000-0003-1424-3620" }, { "id": "Jiang-Jonathan-H", "name": { "family": "Jiang", "given": "Jonathan H." }, "orcid": "0000-0002-5929-8951" }, { "id": "Hao-Jiming", "name": { "family": "Hao", "given": "Jiming" } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Seinfeld-J-H", "name": { "family": "Seinfeld", "given": "John H." }, "orcid": "0000-0003-1344-4068" } ] }, "title": "From COVID-19 to future electrification: Assessing traffic impacts on air quality by a machine-learning model", "ispublished": "pub", "full_text_status": "public", "keywords": "COVID-19; machine learning; air pollution; traffic emissions; vehicular electrification", "note": "\u00a9 2021 National Academy of Sciences. Published under the PNAS license. \n\nContributed by John H. Seinfeld, May 3, 2021 (sent for review February 12, 2021; reviewed by Russell R. Dickerson and Alma Hodzic). \n\nY. Wang, S.P.S., J.H.J., and Y.L.Y. acknowledge support by the Jet Propulsion Laboratory, California Institute of Technology, under contract with NASA. E.A.P. and J.H.S. acknowledge support by the Samsung Corporation (award SAMS.2019GRO). S.Z. acknowledges support by the National Key Research and Development Program of China (grant 2017YFC0212100), the National Natural Science Foundation of China (grant 41977180), and Ford Motor Company. J.Y. acknowledges Leo Gallagher and Daniel Kitowski at the California Department of Transportation, Thomas E. Morrell at the Caltech Library, Jin Tao for helpful information on data inputs, and Yu Zhou at Tsinghua University for useful discussions. \n\nData Availability: All study data are included in the article and/or SI Appendix. \n\nJ.Y. and Y.W. contributed equally to this work. \n\nAuthor contributions: J.Y., Y. Wang, S.Z., and J.H.S. designed research; J.Y., Y. Wen, Y. Wang, and S.Z. performed research; J.Y., Y. Wen, Y. Wang, S.Z., J.P.P., E.A.P., Z.W., Y. Wu, S.P.S., J.H.J., J.H., Y.L.Y., and J.H.S. analyzed data; J.Y., Y. Wen, and S.Z. developed the RF model; and J.Y., Y. Wen, Y. Wang, S.Z., and J.H.S. wrote the paper. \n\nReviewers: R.R.D., University of Maryland, College Park; and A.H., National Center for Atmospheric Research. \n\nThe authors declare no competing interest. \n\nThis article contains supporting information online at https://www.pnas.org/lookup/suppl/doi:10.1073/pnas.2102705118/-/DCSupplemental.\n\nPublished - e2102705118.full.pdf
Supplemental Material - pnas.2102705118.sapp.pdf
", "abstract": "The large fluctuations in traffic during the COVID-19 pandemic provide an unparalleled opportunity to assess vehicle emission control efficacy. Here we develop a random-forest regression model, based on the large volume of real-time observational data during COVID-19, to predict surface-level NO\u2082, O\u2083, and fine particle concentration in the Los Angeles megacity. Our model exhibits high fidelity in reproducing pollutant concentrations in the Los Angeles Basin and identifies major factors controlling each species. During the strictest lockdown period, traffic reduction led to decreases in NO\u2082 and particulate matter with aerodynamic diameters <2.5 \u03bcm by \u201330.1% and \u201317.5%, respectively, but a 5.7% increase in O\u2083. Heavy-duty truck emissions contribute primarily to these variations. Future traffic-emission controls are estimated to impose similar effects as observed during the COVID-19 lockdown, but with smaller magnitude. Vehicular electrification will achieve further alleviation of NO\u2082 levels.", "date": "2021-06-29", "date_type": "published", "publication": "Proceedings of the National Academy of Sciences", "volume": "118", "number": "26", "publisher": "National Academy of Sciences", "pagerange": "Art. No. e2102705118", "id_number": "CaltechAUTHORS:20210623-180037244", "issn": "0027-8424", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210623-180037244", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA/JPL/Caltech" }, { "agency": "Samsung Corporation", "grant_number": "SAMS.2019GRO" }, { "agency": "National Key Research and Development Program of China", "grant_number": "2017YFC0212100" }, { "agency": "National Natural Science Foundation of China", "grant_number": "41977180" }, { "agency": "Ford Motor Company" } ] }, "local_group": { "items": [ { "id": "COVID-19" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1073/pnas.2102705118", "pmcid": "PMC8256029", "primary_object": { "basename": "pnas.2102705118.sapp.pdf", "url": "https://authors.library.caltech.edu/records/dxhed-gjf51/files/pnas.2102705118.sapp.pdf" }, "related_objects": [ { "basename": "e2102705118.full.pdf", "url": "https://authors.library.caltech.edu/records/dxhed-gjf51/files/e2102705118.full.pdf" } ], "resource_type": "article", "pub_year": "2021", "author_list": "Yang, Jiani; Wen, Yifan; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/dzkq8-88z89", "eprint_id": 109273, "eprint_status": "archive", "datestamp": "2023-08-22 10:12:40", "lastmod": "2023-10-23 17:47:22", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Addington-Olivia", "name": { "family": "Addington", "given": "Olivia" } }, { "id": "Zeng-Zhao-Cheng", "name": { "family": "Zeng", "given": "Zhao-Cheng" }, "orcid": "0000-0002-0008-6508" }, { "id": "Pongetti-Thomas-J", "name": { "family": "Pongetti", "given": "Thomas" }, "orcid": "0000-0001-9465-0853" }, { "id": "Shia-Run-Lie", "name": { "family": "Shia", "given": "Run-Lie" }, "orcid": "0000-0003-1911-3120" }, { "id": "Gurney-Kevin-R", "name": { "family": "Gurney", "given": "Kevin R." }, "orcid": "0000-0001-9218-7164" }, { "id": "Liang-Jianming", "name": { "family": "Liang", "given": "Jianming" }, "orcid": "0000-0002-4043-6816" }, { "id": "Roest-Geoffrey", "name": { "family": "Roest", "given": "Geoffrey" } }, { "id": "He-Liyin", "name": { "family": "He", "given": "Liyin" }, "orcid": "0000-0003-4427-1438" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Sander-Stanley-P", "name": { "family": "Sander", "given": "Stanley P." }, "orcid": "0000-0003-1424-3620" } ] }, "title": "Estimating nitrous oxide (N\u2082O) emissions for the Los Angeles Megacity using mountaintop remote sensing observations", "ispublished": "pub", "full_text_status": "public", "keywords": "Nitrous oxide; Urban remote sensing; Los Angeles; Megacity; CLARS", "note": "\u00a9 2021 Elsevier. \n\nReceived 8 July 2020, Revised 2 February 2021, Accepted 9 February 2021, Available online 1 April 2021. \n\nThe views expressed in this article are those of the authors and do not necessarily reflect the official opinions of the funding agencies for this work. We thank A. Andrews and E. Dlugokencky for providing NOAA flask measurements at Mt. Wilson Observatory (National Oceanic and Atmospheric Administration, 2019). The CLARS project receives support from the California Air Resources Board. CLARS-FTS data are available from the authors upon request, and part of the data are available from the NASA Megacities Project at https://megacities.jpl.nasa.gov. A portion of this research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration. O. A. acknowledges support from the Jet Propulsion Laboratory (Maximizing Student Potential in STEM) and from Occidental College (NSF COSMOS). \n\nDeclaration of Competing Interest. None.\n\nSupplemental Material - 1-s2.0-S0034425721000699-mmc1.docx
", "abstract": "Nitrous oxide (N\u2082O) is an important greenhouse gas contributing both to global radiative forcing and ozone depletion. Though N\u2082O emissions are largely derived from agricultural activities, urban sources of N\u2082O also contribute significantly to anthropogenic emissions, but are not well understood and difficult to quantify. This study employs a top-down approach to derive urban N\u2082O emissions for the Los Angeles megacity using a unique dataset from a mountaintop remote sensing instrument, which has been observing greenhouse gas mixing ratios in LA since 2011. CLARS-FTS observations yield a weighted mean of 15.0 \u00b1 0.1 ppb excess XN\u2082O above background in the LA basin from 2013 to 2019. Time series of XN\u2082O_(xs) show a seasonal cycle with a peak-to-peak amplitude of 5.6 \u00b1 2.5 ppb, where greater XN\u2082O_(xs) values are observed during the winter/spring and minima occur in late summer/early fall. A tracer-tracer ratio method is applied using XN\u2082O_(xs) and XCO_(2,xs) observations to estimate top-down N\u2082O emissions for the LA basin during 2013\u20132018. Estimated monthly emissions range from 6 to 19 Gg N\u2082O per month and exhibit a similar seasonal cycle to that observed in XN\u2082O_(xs). Estimated annual emissions fall within the range 124\u2013144 Gg per year for the years 2014\u20132018. These top-down annual estimates are roughly 3 times the official statewide bottom-up inventory for the same time period, but consistent considering uncertainties with other top-down estimates for the LA basin. The discrepancy between top-down emission estimates and the statewide bottom-up inventory highlights the difficulty in constraining N\u2082O emissions, especially for an urban environment.", "date": "2021-06-15", "date_type": "published", "publication": "Remote Sensing of Environment", "volume": "259", "publisher": "Elsevier", "pagerange": "Art. No. 112351", "id_number": "CaltechAUTHORS:20210527-093456773", "issn": "0034-4257", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210527-093456773", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "California Air Resources Board" }, { "agency": "NASA/JPL/Caltech" }, { "agency": "Occidental College" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/j.rse.2021.112351", "primary_object": { "basename": "1-s2.0-S0034425721000699-mmc1.docx", "url": "https://authors.library.caltech.edu/records/dzkq8-88z89/files/1-s2.0-S0034425721000699-mmc1.docx" }, "resource_type": "article", "pub_year": "2021", "author_list": "Addington, Olivia; Zeng, Zhao-Cheng; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/9r8xv-t1r55", "eprint_id": 108469, "eprint_status": "archive", "datestamp": "2023-08-22 09:34:36", "lastmod": "2023-10-23 16:22:14", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Scheller-Eva-L", "name": { "family": "Scheller", "given": "E. L." }, "orcid": "0000-0002-9981-5802" }, { "id": "Ehlmann-B-L", "name": { "family": "Ehlmann", "given": "B. L." }, "orcid": "0000-0002-2745-3240" }, { "id": "Hu-Renyu", "name": { "family": "Hu", "given": "Renyu" }, "orcid": "0000-0003-2215-8485" }, { "id": "Adams-Danica-J", "name": { "family": "Adams", "given": "D. J." }, "orcid": "0000-0001-9897-9680" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Y. L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Long-term drying of Mars by sequestration of ocean-scale volumes of water in the crust", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2021, American Association for the Advancement of Science. \n\nReceived 11 June 2020; accepted 4 March 2021. Published online 16 March 2021. \n\nWe thank A. Hoffmann, P. Mahaffey, C. Webster, H. Franz, J. Stern, D. Breuer, J. Dickson, J. Eiler, J. Grotzinger, Y. Liu, E. Stolper, and the Sample Analysis at Mars (SAM) Science Team for discussion. We thank B. Jakosky and two anonymous referees for suggestions that strengthened the manuscript. \n\nR.H., B.L.E., and Y.L.Y. were supported by a NASA Habitable Worlds grant (NNN13D466T, later changed to 80NM0018F0612). Part of this work was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration (grant 80NM0018D0004). E.L.S. was supported by a NASA Earth and Space Science Fellowship (NESSF) (grant 80NSSC18K1255). D.J.A. was supported by a Future Investigator in NASA Earth and Space Science and Technology (FINESST) fellowship (grant 80NSSC19K1548). \n\nAuthor contributions: E.L.S. drafted the manuscript, developed the code, and performed the simulations for the D/H model. B.L.E. devised the original idea of an integrated approach to a water budget and D/H model. E.L.S., B.L.E., and R.H. developed the water budget and D/H model concept. E.L.S., B.L.E., R.H., D.J.A., and Y.L.Y. adapted the KINETICS model input parameters for this study. D.J.A. implemented the KINETICS adaption, and D.J.A. and Y.L.Y. analyzed the KINETICS output. All authors participated in the writing and editing of the manuscript. \n\nCompeting interests: We declare no competing interests. \n\nData and materials availability: The equations used for the D/H model and our adopted parameter ranges are given in the supplementary materials. The Mars D/H model code, input and output files, the KINETICS data files used for fig. S3, and visualization scripts are all available in the CaltechDATA repository at (48). The KINETICS software was developed by a combination of authors (D.J.A. and Y.L.Y.) and a large number of nonauthors (25, 26), so we do not have permission to distribute the source code. An executable version with adjustable input parameters, to reproduce all simulation scenarios in this paper, is available at the same DOI, 10.22002/D1.1879. The SAM data were taken from the Planetary Data System at https://pds-geosciences.wustl.edu/msl/msl-m-sam-2-rdr-l0-v1/mslsam_1xxx/data; we used level 2 data for samples eid25094, eid25123, eid25173, eid25413, eid25484, eid25515, and eid25538 (5).\n\nAccepted Version - nihms-1730612.pdf
Supplemental Material - abc7717-Scheller-SM.pdf
", "abstract": "Geological evidence shows that ancient Mars had large volumes of liquid water. Models of past hydrogen escape to space, calibrated with observations of the current escape rate, cannot explain the present-day deuterium-to-hydrogen isotope ratio (D/H). We simulated volcanic degassing, atmospheric escape, and crustal hydration on Mars, incorporating observational constraints from spacecraft, rovers, and meteorites. We found that ancient water volumes equivalent to a 100 to 1500 meter global layer are simultaneously compatible with the geological evidence, loss rate estimates, and D/H measurements. In our model, the volume of water participating in the hydrological cycle decreased by 40 to 95% over the Noachian period (~3.7 billion to 4.1 billion years ago), reaching present-day values by ~3.0 billion years ago. Between 30 and 99% of martian water was sequestered through crustal hydration, demonstrating that irreversible chemical weathering can increase the aridity of terrestrial planets.", "date": "2021-04-02", "date_type": "published", "publication": "Science", "volume": "372", "number": "6537", "publisher": "American Association for the Advancement of Science", "pagerange": "56-62", "id_number": "CaltechAUTHORS:20210317-101255646", "issn": "0036-8075", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210317-101255646", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NNN13D466T" }, { "agency": "NASA", "grant_number": "80NM0018F0612" }, { "agency": "NASA/JPL/Caltech", "grant_number": "80NM0018D0004" }, { "agency": "NASA Earth and Space Science Fellowship", "grant_number": "80NSSC18K1255" }, { "agency": "NASA Earth and Space Science and Technology Fellowship", "grant_number": "80NSSC19K1548" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1126/science.abc7717", "pmcid": "PMC8370096", "primary_object": { "basename": "abc7717-Scheller-SM.pdf", "url": "https://authors.library.caltech.edu/records/9r8xv-t1r55/files/abc7717-Scheller-SM.pdf" }, "related_objects": [ { "basename": "nihms-1730612.pdf", "url": "https://authors.library.caltech.edu/records/9r8xv-t1r55/files/nihms-1730612.pdf" } ], "resource_type": "article", "pub_year": "2021", "author_list": "Scheller, E. L.; Ehlmann, B. L.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/w3629-na826", "eprint_id": 108253, "eprint_status": "archive", "datestamp": "2023-08-22 09:16:45", "lastmod": "2023-10-23 16:52:53", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Jiang-Xun", "name": { "family": "Jiang", "given": "Xun" }, "orcid": "0000-0001-8932-3807" }, { "id": "Li-King\u2010Fai", "name": { "family": "Li", "given": "King\u2010Fai" }, "orcid": "0000-0003-0150-2910" }, { "id": "Liang-Mao\u2010Chang", "name": { "family": "Liang", "given": "Mao\u2010Chang" }, "orcid": "0000-0002-5294-9344" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Impact of Amazonian Fires on Atmospheric CO\u2082", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2021 American Geophysical Union. \n\nIssue Online: 26 February 2021; Version of Record online: 26 February 2021; Accepted manuscript online: 16 February 2021; Manuscript accepted: 04 February 2021; Manuscript revised: 02 February 2021; Manuscript received: 01 December 2020. \n\nWe thank R.\u2010L. Shia for helpful comments. We thank two anonymous referees and the editor for their time and constructive suggestions. X. Jiang is supported by NASA ROSES Cassini Data Analysis Program. K.\u2010F. Li is partially supported by NASA JPL Subcontracts 1631379 and 1653138. M.\u2010C. Liang is supported by Ministry of Science and Technology, Taiwan (grant no. 108\u20102111\u2010M\u2010001\u2010011\u2010MY3) and Academia Sinica (grant no. AS\u2010IA\u2010109\u2010M03). Y. L. Yung is supported by the NASA OCO\u20102 project. \n\nData Availability Statement: GPCP Version 2.3 precipitation data are available at https://psl.noaa.gov/data/gridded/data.gpcp.html. NCEP2 Reanalysis data are available at https://psl.noaa.gov/data/gridded/data.ncep.reanalysis2.html. OCO\u20102 Version 9 column CO\u2082 data are available at https://co2.jpl.nasa.gov/#mission=OCO\u20102. AIRS Version 6 column CO data are available at https://airs.jpl.nasa.gov/data/get\u2010data/standard\u2010data/. GFED Version 4.1 data are available at https://www.geo.vu.nl/\u223cgwerf/GFED/GFED4/. MODIS burned area data are available at http://modis\u2010fire.umd.edu/.\n\nPublished - 2020GL091875.pdf
Supplemental Material - 2020gl091875-sup-0001-supporting_information_si-s01.docx
", "abstract": "Amazon rainforest fires have significant environmental and societal impacts, but the mechanism and impact of the fires on the regional and global carbon cycles have not been fully understood. Over the rainforest, less precipitation, higher surface temperature, and enhanced mid\u2010tropospheric sinking air over the eastern part of the Amazon characterized the fire/dry season. These meteorological conditions will facilitate more fires in the Amazon rainforest. Using the Orbiting Carbon Observatory\u20102 column CO\u2082, we notice that there are \u223c2 ppm more CO\u2082 over the Amazon compared with the surrounding area during the fire season. The higher concentrations of atmospheric CO\u2082 are related to the surface biomass burning, enhanced sinking air over the eastern part of the Amazon, and surface winds. Results from this study can help us better understand the carbon sources and sinks over the Amazon during the fire/dry season.", "date": "2021-03-16", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "48", "number": "5", "publisher": "American Geophysical Union", "pagerange": "Art. No. e2020GL091875", "id_number": "CaltechAUTHORS:20210301-134944883", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210301-134944883", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "JPL", "grant_number": "1631379" }, { "agency": "JPL", "grant_number": "1653138" }, { "agency": "Ministry of Science and Technology (Taipei)", "grant_number": "108\u20102111\u2010M\u2010001\u2010011\u2010MY3" }, { "agency": "Academia Sinica", "grant_number": "AS\u2010IA\u2010109\u2010M03" }, { "agency": "NASA", "grant_number": "80NSSC20K0479" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2020gl091875", "primary_object": { "basename": "2020GL091875.pdf", "url": "https://authors.library.caltech.edu/records/w3629-na826/files/2020GL091875.pdf" }, "related_objects": [ { "basename": "2020gl091875-sup-0001-supporting_information_si-s01.docx", "url": "https://authors.library.caltech.edu/records/w3629-na826/files/2020gl091875-sup-0001-supporting_information_si-s01.docx" } ], "resource_type": "article", "pub_year": "2021", "author_list": "Jiang, Xun; Li, King\u2010Fai; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/knwz1-dvb78", "eprint_id": 108255, "eprint_status": "archive", "datestamp": "2023-08-22 09:00:23", "lastmod": "2023-10-23 16:22:32", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Zeng-Zhao-Cheng", "name": { "family": "Zeng", "given": "Zhao-Cheng" }, "orcid": "0000-0002-0008-6508" }, { "id": "Addington-Olivia", "name": { "family": "Addington", "given": "Olivia" } }, { "id": "Pongetti-Thomas-J", "name": { "family": "Pongetti", "given": "Thomas J." }, "orcid": "0000-0001-9465-0853" }, { "id": "Herman-Robert-L", "name": { "family": "Herman", "given": "Robert L." }, "orcid": "0000-0001-7063-6424" }, { "id": "Sung-Keeyoon", "name": { "family": "Sung", "given": "Keeyoon" }, "orcid": "0000-0002-8030-7410" }, { "id": "Newman-Sally", "name": { "family": "Newman", "given": "Sally" }, "orcid": "0000-0003-0710-995X" }, { "id": "Schneider-Andreas", "name": { "family": "Schneider", "given": "Andreas" } }, { "id": "Borsdorff-Tobias", "name": { "family": "Borsdorff", "given": "Tobias" }, "orcid": "0000-0002-4421-0187" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Sander-Stanley-P", "name": { "family": "Sander", "given": "Stanley P." }, "orcid": "0000-0003-1424-3620" } ] }, "title": "Measurements of atmospheric HDO/H\u2082O in southern California from CLARS-FTS", "ispublished": "unpub", "full_text_status": "public", "note": "License: Non-exclusive. \n\nPublished Online: Sat, 27 Feb 2021. \n\nWe would like to thank Geoffrey Toon (JPL) for proofreading and suggestions on the first draft of this manuscript, and Paul Wennberg (Caltech) and Coleen Roehl (Caltech) for providing the TCCON data. OA would like to thank the National Science Foundation COSMOS Scholarship, the Maximizing Student Potential in STEM program at the Jet Propulsion Laboratory, and Occidental College Undergraduate Research Center for helping to fund the summer experience. The CLARS project receives support from the California Air Resources Board. However, the results presented in this study do not necessarily present the views of the funding agency. Part of the CLARS-FTS data are available from the NASA Megacities Project at https://megacities.jpl.nasa.gov. The TROPOMI HDO data set from this study is available for download at ftp://ftp.sron.nl/open-access-data-2/TROPOMI/tropomi/hdo/9_1/ (last access: 12 December 2020). TCCON data are available from the TCCON Data Archive: https://doi.org/10.14291/tccon.ggg2014.pasadena01.r1/1182415. Part of the research described in this article was performed at the Jet Propulsion Laboratory, California Institute of Technology and NASA under contracts with the National Aeronautics and Space Administration.\n\nSubmitted - essoar.10506339.1.pdf
", "abstract": "Atmospheric isotopologues of water vapor (e.g., HDO) are important tracers for understanding Earth's hydrological cycles. Most remote sensing measurements of these isotopologues, however, are column averaged values and sparse in space and time. Measurements targeting the planetary boundary layer (PBL) are much rarer. In this study, we retrieved HDO and H from CLARS-FTS observations (2011-2019). The isotopological abundance \u03b4D, which represents the relative difference of the HDO/H\u2082O ratio to a standard abundance ratio, is also calculated. The averaged \u03b4D retrievals are (\u2212156.1\u00b160.0)\u2030 with an uncertainty of (6.1\u00b110.2)\u2030 for LA Basin Survey m and (\u2212344.7\u00b195.0)\u2030 with an uncertainty of (42.4\u00b131.6)\u2030 for Spectralon Viewing Observation mode. In LA, the \u03b4D shows a seasonal cycle that is primarily driven by the change of atmospheric humidity. The temporal variabilities in \u03b4D data between CLARS-FTS and a collocated Total Carbon Column Observing Network (TCCON) observatory are highly correlated. The difference between CLARS and TCCON \u03b4D retrievals can primarily be attributed to the difference in their observation geometries. We conclude that the HDO and \u03b4D measurements from CLARS-FTS provide high spatial and temporal resolution datasets for further study of hydrological processes in the LA megacity.", "date": "2021-03-02", "date_type": "published", "publisher": "Caltech Library", "id_number": "CaltechAUTHORS:20210301-145107206", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210301-145107206", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF" }, { "agency": "NASA/JPL/Caltech" }, { "agency": "Occidental College" }, { "agency": "California Air Resources Board" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "primary_object": { "basename": "essoar.10506339.1.pdf", "url": "https://authors.library.caltech.edu/records/knwz1-dvb78/files/essoar.10506339.1.pdf" }, "resource_type": "monograph", "pub_year": "2021", "author_list": "Zeng, Zhao-Cheng; Addington, Olivia; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/qcaga-3cf44", "eprint_id": 104356, "eprint_status": "archive", "datestamp": "2023-08-22 09:10:00", "lastmod": "2023-10-20 19:20:40", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Gladstone-G-Randall", "name": { "family": "Gladstone", "given": "G. Randall" }, "orcid": "0000-0003-0060-072X" }, { "id": "Kammer-Joshua-A", "name": { "family": "Kammer", "given": "Joshua A." }, "orcid": "0000-0002-3441-3757" }, { "id": "Adams-Danica-J", "name": { "family": "Adams", "given": "Danica J." }, "orcid": "0000-0001-9897-9680" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Pryor-Wayne-R", "name": { "family": "Pryor", "given": "Wayne R." }, "orcid": "0000-0001-8112-8783" }, { "id": "Strobel-Darrell-F", "name": { "family": "Strobel", "given": "Darrell F." }, "orcid": "0000-0002-0944-8675" }, { "id": "Young-Leslie-A", "name": { "family": "Young", "given": "Leslie A." }, "orcid": "0000-0002-7547-3967" }, { "id": "Parker-Joel-Wm", "name": { "family": "Parker", "given": "Joel Wm." }, "orcid": "0000-0002-3672-0603" }, { "id": "Stern-S-Alan", "name": { "family": "Stern", "given": "S. Alan" } } ] }, "title": "Constraints on Pluto's H and CH\u2084 profiles from New Horizons Alice Ly\u03b1 observations", "ispublished": "pub", "full_text_status": "public", "keywords": "Pluto; Atmosphere; Aeronomy; Ultraviolet observations", "note": "\u00a9 2020 The Authors. Published by Elsevier Inc. This is an open access article under the CC BY-NC-ND license. \n\nReceived 4 April 2020, Revised 25 June 2020, Accepted 5 July 2020, Available online 11 July 2020. \n\nWe thank Tanguy Bertrand and Francois Forget for useful discussions, and the reviewers for useful comments. This work was supported by NASA through contract NASW02008 to SwRI.\n\nPublished - 1-s2.0-S0019103520303390-main.pdf
", "abstract": "The Alice spectrograph on New Horizons performed several far-ultraviolet (FUV) airglow observations during the July 2015 flyby of Pluto. One of these observations, named PColor2, was a short (226 s) scan across the dayside disk of Pluto from a range of \u223c34,000 km, at about 40 minutes prior to closest approach. The brightest observed FUV airglow signal at Pluto is the Lyman alpha (Ly\u03b1) emission line of atomic hydrogen, which arises primarily through the resonant scattering of solar Ly\u03b1 by H atoms in the upper atmosphere, with a brightness of about 30 Rayleighs. Pluto appears dark against the much brighter (\u223c100 Rayleigh) sky background; this sky background is likewise the result of resonantly scattered solar Ly\u03b1, in this case by H atoms in the interplanetary medium (IPM). Here we use an updated photochemical model and a resonance line radiative transfer model to perform detailed simulations of the Ly\u03b1 emissions observed in the Alice PColor2 scan. The photochemical models show that H and CH\u2084 abundances in Pluto's upper atmosphere are a very strong function of the near-surface mixing ratio of CH\u2084, and could provide a useful way to remotely monitor seasonal climate variations in Pluto's lower atmosphere. The morphology of the PColor2 Ly\u03b1 emissions provides constraints on the current abundance profiles of H atoms and CH\u2084 molecules in Pluto's atmosphere, and indicate that the globally averaged near-surface mixing ratio of CH\u2084 is currently close to 0.4%. This new result thus provides independent confirmation of one of the primary results from the solar occultation, also observed with the New Horizons Alice ultraviolet spectrograph.", "date": "2021-03-01", "date_type": "published", "publication": "Icarus", "volume": "356", "publisher": "Elsevier", "pagerange": "Art. No. 113973", "id_number": "CaltechAUTHORS:20200713-123919818", "issn": "0019-1035", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200713-123919818", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NASW02008" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/j.icarus.2020.113973", "primary_object": { "basename": "1-s2.0-S0019103520303390-main.pdf", "url": "https://authors.library.caltech.edu/records/qcaga-3cf44/files/1-s2.0-S0019103520303390-main.pdf" }, "resource_type": "article", "pub_year": "2021", "author_list": "Gladstone, G. Randall; Kammer, Joshua A.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/r8378-fhv62", "eprint_id": 104455, "eprint_status": "archive", "datestamp": "2023-08-22 09:10:09", "lastmod": "2023-10-20 20:29:36", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Chen-Sihe", "name": { "family": "Chen", "given": "Sihe" } }, { "id": "Young-Eliot-F", "name": { "family": "Young", "given": "Eliot F." }, "orcid": "0000-0001-8242-1076" }, { "id": "Young-Leslie-A", "name": { "family": "Young", "given": "Leslie A." }, "orcid": "0000-0002-7547-3967" }, { "id": "Bertrand-Tanguy", "name": { "family": "Bertrand", "given": "Tanguy" }, "orcid": "0000-0002-2302-9776" }, { "id": "Forget-Fran\u00e7ois", "name": { "family": "Forget", "given": "Fran\u00e7ois" }, "orcid": "0000-0002-3262-4366" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Global climate model occultation lightcurves tested by August 2018 ground-based stellar occultation", "ispublished": "pub", "full_text_status": "public", "keywords": "Pluto; Pluto, atmosphere; Occultations", "note": "\u00a9 2020 Elsevier Inc. \n\nReceived 21 December 2019, Revised 29 June 2020, Accepted 9 July 2020, Available online 19 July 2020. \n\nThis work is supported in part by NASA 000329-P2232440 to Caltech, and by NSF 1616115 and NASA SSO 80NSSC19K0824 to SwRI. \n\nThe authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.\n\nAccepted Version - 2102.04666.pdf
", "abstract": "Pluto's atmospheric profiles (temperature and pressure) have been studied for decades from stellar occultation lightcurves. In this paper, we look at recent Pluto Global Climate Model (GCM) results (3D temperature, pressure, and density fields) from Bertrand et al. (2020) and use the results to generate model observer's plane intensity fields (OPIF) and lightcurves by using a Fourier optics scheme to model light passing through Pluto's atmosphere (Young, 2012). This approach can accommodate arbitrary atmospheric structures and 3D distributions of haze. We compared the GCM model lightcurves with the lightcurves observed during the 15-AUG-2018 Pluto stellar occultation. We find that the climate scenario which best reproduces the observed data includes a N2 ice mid latitude band in the southern hemisphere. We have also studied different haze and P/T ratio profiles: the haze effectively reduces the central flash strength, and a lower P/T ratio both reduces the central flash strength and incurs anomalies in the shoulders of the central flash.", "date": "2021-03-01", "date_type": "published", "publication": "Icarus", "volume": "356", "publisher": "Elsevier", "pagerange": "Art. No. 113976", "id_number": "CaltechAUTHORS:20200720-130843170", "issn": "0019-1035", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200720-130843170", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "000329-P2232440" }, { "agency": "NSF", "grant_number": "AST-1616115" }, { "agency": "NASA", "grant_number": "80NSSC19K0824" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/j.icarus.2020.113976", "primary_object": { "basename": "2102.04666.pdf", "url": "https://authors.library.caltech.edu/records/r8378-fhv62/files/2102.04666.pdf" }, "resource_type": "article", "pub_year": "2021", "author_list": "Chen, Sihe; Young, Eliot F.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/3xdtn-z9j84", "eprint_id": 107630, "eprint_status": "archive", "datestamp": "2023-08-22 09:03:47", "lastmod": "2023-10-23 16:04:16", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Cai-Xiang", "name": { "family": "Cai", "given": "Xiang" } }, { "id": "Jiang-Jonathan-H", "name": { "family": "Jiang", "given": "Jonathan H." }, "orcid": "0000-0002-5929-8951" }, { "id": "Fahy-Kristen-A", "name": { "family": "Fahy", "given": "Kristen A." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "A Statistical Estimation of the Occurrence of Extraterrestrial Intelligence in the Milky Way Galaxy", "ispublished": "pub", "full_text_status": "public", "keywords": "Fermi Paradox; extraterrestrial intelligence; Milky Way Galaxy", "note": "\u00a9 2021 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/). \n\nReceived: 13 December 2020 / Revised: 11 January 2021 / Accepted: 12 January 2021 / Published: 18 January 2021. \n\nThis research was supported by the Jet Propulsion Laboratory, California Institute of Technology, under the contract with NASA. We acknowledge the partial funding support from the NASA Exoplanet Research Program NNH18ZDA001N-2XRP. We also thank the Virtual Planetary Laboratory at the University of Washington for support. \n\nThis research was funded by the NASA Exoplanet Research Program NNH18ZDA001N-2XRP. \n\nAuthor Contributions. Conceptualization, J.H.J.; methodology, X.C. and J.H.J.; software, X.C. and J.H.J.; validation, J.H.J., K.A.F., and Y.L.Y.; formal analysis, X.C. and J.H.J.; investigation, X.C. and J.H.J.; resources, J.H.J.; data curation, X.C. and J.H.J.; writing\u2014original draft preparation, X.C. and J.H.J.; writing\u2014review and editing, J.H.J., K.A.F., and Y.L.Y.; visualization, X.C. and J.H.J.; supervision, J.H.J.; project administration, J.H.J.; funding acquisition, J.H.J. and Y.L.Y. All authors have read and agreed to the published version of the manuscript. \n\nData Availability Statement. The data underlying this article are available in the article. For additional questions regarding the data sharing, please contact the corresponding author at Jonathan.H.Jiang@jpl.nasa.gov. \n\nInstitutional Review Board Statement. This article has been approved for unlimited release by the Document Review Services at the Jet Propulsion Laboratory (JPL), California Institute of Technology. Record: URS297443; Submitted by author: Jonathan H Jiang on 12/13/2020; Document Type: Journal Article; Title: A Statistical Estimation of the Occurrence of Extraterrestrial Intelligence in the Milky Way Galaxy; The JPL clearance number is CL#21-0186. \n\nInformed Consent Statement. Not applicable. \n\nThe authors declare no conflict of interest.\n\nPublished - galaxies-09-00005.pdf
Accepted Version - 2012.07902.pdf
", "abstract": "In the field of astrobiology, the precise location, prevalence, and age of potential extraterrestrial intelligence (ETI) have not been explicitly explored. Here, we address these inquiries using an empirical galactic simulation model to analyze the spatial\u2013temporal variations and the prevalence of potential ETI within the Galaxy. This model estimates the occurrence of ETI, providing guidance on where to look for intelligent life in the Search for ETI (SETI) with a set of criteria, including well-established astrophysical properties of the Milky Way. Further, typically overlooked factors such as the process of abiogenesis, different evolutionary timescales, and potential self-annihilation are incorporated to explore the growth propensity of ETI. We examine three major parameters: (1) the likelihood rate of abiogenesis (\u03bb_A); (2) evolutionary timescales (T_(evo)); and (3) probability of self-annihilation of complex life (P_(ann)). We found P_(ann) to be the most influential parameter determining the quantity and age of galactic intelligent life. Our model simulation also identified a peak location for ETI at an annular region approximately 4 kpc from the galactic center around 8 billion years (Gyrs), with complex life decreasing temporally and spatially from the peak point, asserting a high likelihood of intelligent life in the galactic inner disk. The simulated age distributions also suggest that most of the intelligent life in our galaxy are young, thus making observation or detection difficult.", "date": "2021-03", "date_type": "published", "publication": "Galaxies", "volume": "9", "number": "1", "publisher": "MDPI", "pagerange": "Art. No. 5", "id_number": "CaltechAUTHORS:20210121-101411121", "issn": "2075-4434", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210121-101411121", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA/JPL/Caltech" }, { "agency": "NASA", "grant_number": "NNH18ZDA001N-2XRP" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.3390/galaxies9010005", "primary_object": { "basename": "2012.07902.pdf", "url": "https://authors.library.caltech.edu/records/3xdtn-z9j84/files/2012.07902.pdf" }, "related_objects": [ { "basename": "galaxies-09-00005.pdf", "url": "https://authors.library.caltech.edu/records/3xdtn-z9j84/files/galaxies-09-00005.pdf" } ], "resource_type": "article", "pub_year": "2021", "author_list": "Cai, Xiang; Jiang, Jonathan H.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/5dmby-n3v45", "eprint_id": 108150, "eprint_status": "archive", "datestamp": "2023-08-22 09:05:16", "lastmod": "2023-10-23 16:29:51", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Gu-Lixiang", "name": { "family": "Gu", "given": "Lixiang" }, "orcid": "0000-0002-3089-3706" }, { "id": "Fan-Siteng", "name": { "family": "Fan", "given": "Siteng" }, "orcid": "0000-0002-3041-4680" }, { "id": "Li-Jiazheng", "name": { "family": "Li", "given": "Jiazheng" }, "orcid": "0000-0002-2563-6289" }, { "id": "Bartlett-Stuart-J", "name": { "family": "Bartlett", "given": "Stuart J." }, "orcid": "0000-0001-5680-476X" }, { "id": "Natraj-Vijay", "name": { "family": "Natraj", "given": "Vijay" }, "orcid": "0000-0003-3154-9429" }, { "id": "Jiang-Jonathan-H", "name": { "family": "Jiang", "given": "Jonathan H." }, "orcid": "0000-0002-5929-8951" }, { "id": "Crisp-David", "name": { "family": "Crisp", "given": "David" }, "orcid": "0000-0002-4573-9998" }, { "id": "Hu-Yongyun", "name": { "family": "Hu", "given": "Yongyun" }, "orcid": "0000-0002-4003-4630" }, { "id": "Tinetti-Giovanna", "name": { "family": "Tinetti", "given": "Giovanna" }, "orcid": "0000-0001-6058-6654" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Earth as a Proxy Exoplanet: Deconstructing and Reconstructing Spectrophotometric Light Curves", "ispublished": "pub", "full_text_status": "public", "keywords": "Exoplanet astronomy; Exoplanet atmospheres; Exoplanet surfaces; Exoplanets; Exoplanet structure; Exoplanet surface variability; Extrasolar rocky planets; Habitable planets; Exoplanet surface characteristics; Exoplanet atmospheric composition; Exoplanet atmospheric variability; Exoplanet surface composition", "note": "\u00a9 2021 The American Astronomical Society. \n\nReceived 2020 September 3; revised 2020 December 10; accepted 2020 December 17; published 2021 February 16. \n\nL.G. and Y.H. are supported by the National Natural Science Foundation under grants 41530423, 41888101, and 41761144072. L.G. is also partly supported by the China Scholarship Council. A portion of this research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration (80NM0018D0004). D.C. and Y.L.Y. acknowledge support from the Virtual Planetary Laboratory at the University of Washington. Y.H. is also supported by the research project of Technology of Space Telescope Detecting Exoplanets and Life (D030201). G.T. was supported by the Science and Technology Funding Council of UK and UK Space Agency (ST/T001836/1, ST/V003380/1). J.H.J., S.J.B., and Y.L.Y. acknowledge funding support from the NASA Exoplanet Research Program NNH18ZDA001N-2XRP.\n\nPublished - Gu_2021_AJ_161_122.pdf
Accepted Version - 2012.10556.pdf
", "abstract": "Point-source spectrophotometric (single-point) light curves of Earth-like planets contain a surprising amount of information about the spatial features of those worlds. Spatially resolving these light curves is important for assessing time-varying surface features and the existence of an atmosphere, which in turn is critical to life on Earth and significant for determining habitability on exoplanets. Given that Earth is the only celestial body confirmed to harbor life, treating it as a proxy exoplanet by analyzing time-resolved spectral images provides a benchmark in the search for habitable exoplanets. The Earth Polychromatic Imaging Camera (EPIC) on the Deep Space Climate Observatory (DSCOVR) provides such an opportunity, with observations of ~5000 full-disk sunlit Earth images each year at 10 wavelengths with high temporal frequency. We disk-integrate these spectral images to create single-point light curves and decompose them into principal components (PCs). Using machine-learning techniques to relate the PCs to six preselected spatial features, we find that the first and fourth PCs of the single-point light curves, contributing ~83.23% of the light-curve variability, contain information about low and high clouds, respectively. Surface information relevant to the contrast between land and ocean reflectance is contained in the second PC, while individual land subtypes are not easily distinguishable (<0.1% total light-curve variation). We build an Earth model by systematically altering the spatial features to derive causal relationships to the PCs. This model can serve as a baseline for analyzing Earth-like exoplanets and guide wavelength selection and sampling strategies for future observations.", "date": "2021-03", "date_type": "published", "publication": "Astronomical Journal", "volume": "161", "number": "3", "publisher": "American Astronomical Society", "pagerange": "Art. No. 122", "id_number": "CaltechAUTHORS:20210223-090759375", "issn": "0004-6256", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210223-090759375", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "National Natural Science Foundation of China", "grant_number": "41530423" }, { "agency": "National Natural Science Foundation of China", "grant_number": "41888101" }, { "agency": "National Natural Science Foundation of China", "grant_number": "41761144072" }, { "agency": "China Scholarship Council" }, { "agency": "NASA", "grant_number": "80NM0018D0004" }, { "agency": "NASA/JPL/Caltech" }, { "agency": "University of Washington" }, { "agency": "Technology of Space Telescope Detecting Exoplanets and Life", "grant_number": "D030201" }, { "agency": "Science and Technology Facilities Council (STFC)", "grant_number": "ST/T001836/1" }, { "agency": "Science and Technology Facilities Council (STFC)", "grant_number": "ST/V003380/1" }, { "agency": "NASA", "grant_number": "NNH18ZDA001N-2XRP" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.3847/1538-3881/abd54a", "primary_object": { "basename": "2012.10556.pdf", "url": "https://authors.library.caltech.edu/records/5dmby-n3v45/files/2012.10556.pdf" }, "related_objects": [ { "basename": "Gu_2021_AJ_161_122.pdf", "url": "https://authors.library.caltech.edu/records/5dmby-n3v45/files/Gu_2021_AJ_161_122.pdf" } ], "resource_type": "article", "pub_year": "2021", "author_list": "Gu, Lixiang; Fan, Siteng; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/wfgve-nfe63", "eprint_id": 107380, "eprint_status": "archive", "datestamp": "2023-08-22 08:25:34", "lastmod": "2023-10-23 15:50:12", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Pinto-Joseph-P", "name": { "family": "Pinto", "given": "Joseph P." } }, { "id": "Li-Jiazheng", "name": { "family": "Li", "given": "Jiazheng" }, "orcid": "0000-0002-2563-6289" }, { "id": "Mills-Franklin-P", "name": { "family": "Mills", "given": "Franklin P." }, "orcid": "0000-0002-4270-7333" }, { "id": "Marcq-Emmanuel", "name": { "family": "Marcq", "given": "Emmanuel" }, "orcid": "0000-0002-1924-641X" }, { "id": "Evdokimova-Daria", "name": { "family": "Evdokimova", "given": "Daria" }, "orcid": "0000-0002-8722-0000" }, { "id": "Belyaev-Denis", "name": { "family": "Belyaev", "given": "Denis" }, "orcid": "0000-0003-1123-5983" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Sulfur monoxide dimer chemistry as a possible source of polysulfur in the upper atmosphere of Venus", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 The Author(s) 2021. This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/. \n\nReceived 11 May 2020; Accepted 27 November 2020; Published 08 January 2021. \n\nThis research was supported by NASA Grant P1969079 under subcontract to the Space Science Institute (SSI) and NASA grant NNX16AN03G to SSI. D.E. and D.B. (IKI) acknowledge funding from the Russian government (topic VENERA). D.E. acknowledges the support by the French Government Scholarship Vernadski for PhD students. \n\nData availability: The model data and observational data that support the findings of this study are available from the corresponding author on reasonable request. \n\nCode availability: The code for the photochemical model written in Fortran and the post processing of the data written in Matlab is available from the corresponding author on reasonable request. \n\nAuthor Contributions: J.P.P., J.L., F.P.M., and Y.L.Y. contributed to the paper writing. J.P.P., J.L., and F.P.M. carried out the modelling work. E.M., D.E., and D.B. provided the data from Venus Express. Y.L.Y. supervised the research. \n\nThe authors declare no competing interests. \n\nPeer review information: Nature Communications thanks Vladimir Krasnopolsky and the other, anonymous, reviewer for their contribution to the peer review of this work. Peer reviewer reports are available.\n\nPublished - s41467-020-20451-2.pdf
Supplemental Material - 41467_2020_20451_MOESM1_ESM.pdf
Supplemental Material - 41467_2020_20451_MOESM2_ESM.pdf
", "abstract": "The abundance of SO dimers (SO)\u2082 in the upper atmosphere of Venus and their implications for the enigmatic ultraviolet absorption has been investigated in several studies over the past few years. However, the photochemistry of sulfur species in the upper atmosphere of Venus is still not well understood and the identity of the missing ultraviolet absorber(s) remains unknown. Here we update an existing photochemical model of Venus' upper atmosphere by including the photochemistry of SO dimers. Although the spectral absorption profile of SO dimers fits the unknown absorber, their abundance is found to be too low for them to contribute significantly to the absorption. It is more likely that their photolysis and/or reaction products could contribute more substantively. Reactions of SO dimers are found to be important sources of S\u2082O, and possibly higher order S_nO species and polysulfur, S_n. All of these species absorb in the critical ultraviolet region and are expected to be found in both the aerosol and gas phase. indicating that in-situ high resolution aerosol mass spectrometry might be a useful technique for identifying the ultraviolet absorber on Venus.", "date": "2021-01-08", "date_type": "published", "publication": "Nature Communications", "volume": "12", "publisher": "Nature Publishing Group", "pagerange": "Art. No. 175", "id_number": "CaltechAUTHORS:20210108-110214435", "issn": "2041-1723", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210108-110214435", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "P1969079" }, { "agency": "NASA", "grant_number": "NNX16AN03G" }, { "agency": "Russian Foundation for Basic Research" }, { "agency": "French Government Scholarship" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1038/s41467-020-20451-2", "primary_object": { "basename": "41467_2020_20451_MOESM1_ESM.pdf", "url": "https://authors.library.caltech.edu/records/wfgve-nfe63/files/41467_2020_20451_MOESM1_ESM.pdf" }, "related_objects": [ { "basename": "41467_2020_20451_MOESM2_ESM.pdf", "url": "https://authors.library.caltech.edu/records/wfgve-nfe63/files/41467_2020_20451_MOESM2_ESM.pdf" }, { "basename": "s41467-020-20451-2.pdf", "url": "https://authors.library.caltech.edu/records/wfgve-nfe63/files/s41467-020-20451-2.pdf" } ], "resource_type": "article", "pub_year": "2021", "author_list": "Pinto, Joseph P.; Li, Jiazheng; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/d20fk-s9h97", "eprint_id": 107363, "eprint_status": "archive", "datestamp": "2023-08-22 08:02:28", "lastmod": "2023-10-23 15:48:57", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Huang-Yunxia", "name": { "family": "Huang", "given": "Yunxia" } }, { "id": "Natraj-Vijay", "name": { "family": "Natraj", "given": "Vijay" }, "orcid": "0000-0003-3154-9429" }, { "id": "Zeng-Zhao-Cheng", "name": { "family": "Zeng", "given": "Zhao-Cheng" }, "orcid": "0000-0002-0008-6508" }, { "id": "Kopparla-Pushkar", "name": { "family": "Kopparla", "given": "Pushkar" }, "orcid": "0000-0002-8951-3907" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Quantifying the impact of aerosol scattering on the retrieval of methane from airborne remote sensing measurements", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 Author(s) 2020. This work is distributed under the Creative Commons Attribution 4.0 License. \n\nReceived: 20 Feb 2020 \u2013 Discussion started: 12 May 2020 \u2013 Revised: 14 Oct 2020 \u2013 Accepted: 16 Oct 2020 \u2013 Published: 15 Dec 2020. \n\nA portion of this research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration (80NM0018D0004). The authors gratefully acknowledge the insightful and constructive comments from the two anonymous reviewers, which improved the clarity and quality of the manuscript and elevated the significance of the work beyond the original expectation. \n\nData availability: The code and data are available from the authors upon request. \n\nAuthor contributions: VN conceived the work, provided the radiative transfer and aerosol models, supervised YH, and assisted with manuscript preparation. YH designed and performed the retrievals, analyzed the results, and prepared the original manuscript. ZCZ contributed to retrieval setup and assisted with analysis of the results. PK provided valuable inputs into the science of CH4 remote sensing. YLY supervised YH and participated in the evaluation of the retrieval results and intercomparison. All listed authors contributed to the review and editing of this paper. \n\nThe authors declare that there is no conflict of interest. \n\nThis research has been supported by the NASA \"Utilization of Airborne Visible/Infrared Imaging Spectrometer Next Generation Data from an Airborne Campaign in India\" program (grant no. NNH16ZDA001N-AVRSNG) and the Jet Propulsion Laboratory Research and Technology Development program. PK was funded by the Japan Society for the Promotion of Science International Research Fellow Program. \n\nReview statement: This paper was edited by Jun Wang and reviewed by two anonymous referees.\n\nPublished - amt-13-6755-2020.pdf
", "abstract": "As a greenhouse gas with strong global warming potential, atmospheric methane (CH\u2084) emissions have attracted a great deal of attention. Although remote sensing measurements can provide information about CH\u2084 sources and emissions, accurate retrieval is challenging due to the influence of atmospheric aerosol scattering. In this study, imaging spectroscopic measurements from the Airborne Visible/Infrared Imaging Spectrometer \u2013 Next Generation (AVIRIS-NG) in the shortwave infrared are used to compare two retrieval techniques \u2013 the traditional matched filter (MF) method and the optimal estimation (OE) method, which is a popular approach for trace gas retrievals. Using a numerically efficient radiative transfer model with an exact single-scattering component and a two-stream multiple-scattering component, we also simulate AVIRIS-NG measurements for different scenarios and quantify the impact of aerosol scattering in the two retrieval schemes by including aerosols in the simulations but not in the retrievals. The presence of aerosols causes an underestimation of CH\u2084 in both the MF and OE retrievals; the biases increase with increasing surface albedo and aerosol optical depth (AOD). Aerosol types with high single-scattering albedo and low asymmetry parameter (such as water-soluble aerosols) induce large biases in the retrieval. When scattering effects are neglected, the MF method exhibits lower fractional retrieval bias compared to the OE method at high CH\u2084 concentrations (2\u20135 times typical background values) and is suitable for detecting strong CH\u2084 emissions. For an AOD value of 0.3, the fractional biases of the MF retrievals are between 1.3\u2009% and 4.5\u2009%, while the corresponding values for OE retrievals are in the 2.8\u2009%\u20135.6\u2009% range. On the other hand, the OE method is an optimal technique for diffuse sources (<1.5 times typical background values), showing up to 5 times smaller fractional retrieval bias (8.6\u2009%) than the MF method (42.6\u2009%) for the same AOD scenario. However, when aerosol scattering is significant, the OE method is superior since it provides a means to reduce biases by simultaneously retrieving AOD, surface albedo, and CH\u2084. The results indicate that, while the MF method is good for plume detection, the OE method should be employed to quantify CH\u2084 concentrations, especially in the presence of aerosol scattering.", "date": "2020-12-15", "date_type": "published", "publication": "Atmospheric Measurement Techniques", "volume": "13", "number": "12", "publisher": "European Geosciences Union", "pagerange": "6755-6769", "id_number": "CaltechAUTHORS:20210107-110632015", "issn": "1867-8548", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210107-110632015", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA/JPL/Caltech" }, { "agency": "NASA", "grant_number": "80NM0018D0004" }, { "agency": "NASA", "grant_number": "NNH16ZDA001N-AVRSNG" }, { "agency": "Japan Society for the Promotion of Science (JSPS)" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/amt-13-6755-2020", "primary_object": { "basename": "amt-13-6755-2020.pdf", "url": "https://authors.library.caltech.edu/records/d20fk-s9h97/files/amt-13-6755-2020.pdf" }, "resource_type": "article", "pub_year": "2020", "author_list": "Huang, Yunxia; Natraj, Vijay; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/wzb1a-qze42", "eprint_id": 107094, "eprint_status": "archive", "datestamp": "2023-08-22 07:59:45", "lastmod": "2023-10-23 15:31:01", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Zhao-Daniel", "name": { "family": "Zhao", "given": "Daniel" } }, { "id": "Bartlett-Stuart-J", "name": { "family": "Bartlett", "given": "Stuart" }, "orcid": "0000-0001-5680-476X" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Quantifying Mineral-Ligand Structural Similarities: Bridging the Geological World of Minerals with the Biological World of Enzymes", "ispublished": "pub", "full_text_status": "public", "keywords": "origin of life; minerals; enzymes; ligand; astrobiology", "note": "\u00a9 2020 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/). \n\nReceived: 14 September 2020 / Revised: 15 November 2020 / Accepted: 7 December 2020 / Published: 10 December 2020. \n\n(This article belongs to the Special Issue From Messy Chemistry to the Origin of Life) \n\nWe wish to thank Yamei Li of the Earth-Life Science Institute for invaluable advice and help during this work. We also wish to thank Michael Russell for his assistance and feedback, Hyman Hartman and Michael Wong for inspiring discussions, and the Caltech GPS 'Astrobiothermoevo' reading group. We gratefully acknowledge the feedback of four reviewers. \n\nThis work was supported by the Caltech Division of Geological and Planetary Sciences Discovery Fund. Y.L.Y. was supported in part by an NAI Virtual Planetary Laboratory grant from the University of Washington to the Jet Propulsion Laboratory and California Institute of Technology. \n\nAuthor Contributions. S.B. conceived the idea of applying a big data, structural comparison of minerals and enzyme ligands, and provided guidance to D.Z., who sourced the mineral and ligand structures, designed the crystal structure manipulation method, performed the analysis and structure comparisons, produced the figures and wrote most of the text. Y.L.Y. provided guidance and assistance throughout the project. All authors have read and agreed to the published version of the manuscript. \n\nThe authors declare no conflict of interest.\n\nPublished - life-10-00338.pdf
", "abstract": "Metal compounds abundant on Early Earth are thought to play an important role in the origins of life. Certain iron-sulfur minerals for example, are proposed to have served as primitive metalloenzyme cofactors due to their ability to catalyze organic synthesis processes and facilitate electron transfer reactions. An inherent difficulty with studying the catalytic potential of many metal compounds is the wide range of data and parameters to consider when searching for individual minerals and ligands of interest. Detecting mineral-ligand pairs that are structurally analogous enables more relevant selections of data to study, since structural affinity is a key indicator of comparable catalytic function. However, current structure-oriented approaches tend to be subjective and localized, and do not quantify observations or compare them with other potential targets. Here, we present a mathematical approach that compares structural similarities between various minerals and ligands using molecular similarity metrics. We use an iterative substructure search in the crystal lattice, paired with benchmark structural similarity methods. This structural comparison may be considered as a first stage in a more advanced analysis tool that will include a range of chemical and physical factors when computing mineral-ligand similarity. This approach will seek relationships between the mineral and enzyme worlds, with applications to the origins of life, ecology, catalysis, and astrobiology.", "date": "2020-12-10", "date_type": "published", "publication": "Life", "volume": "10", "number": "12", "publisher": "MDPI", "pagerange": "Art. No. 338", "id_number": "CaltechAUTHORS:20201215-141036988", "issn": "2075-1729", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201215-141036988", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Caltech Division of Geological and Planetary Sciences" }, { "agency": "JPL/Caltech" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.3390/life10120338", "pmcid": "PMC7764262", "primary_object": { "basename": "life-10-00338.pdf", "url": "https://authors.library.caltech.edu/records/wzb1a-qze42/files/life-10-00338.pdf" }, "resource_type": "article", "pub_year": "2020", "author_list": "Zhao, Daniel; Bartlett, Stuart; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/p2aef-p8016", "eprint_id": 107516, "eprint_status": "archive", "datestamp": "2023-08-20 00:46:27", "lastmod": "2023-10-20 23:01:17", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Wang-Yuan", "name": { "family": "Wang", "given": "Yuan" }, "orcid": "0000-0001-6657-8401" }, { "id": "Zheng-Xiaojian", "name": { "family": "Zheng", "given": "Xiaojian" }, "orcid": "0000-0001-5913-719X" }, { "id": "Dong-Xiquan", "name": { "family": "Dong", "given": "Xiquan" }, "orcid": "0000-0002-3359-6117" }, { "id": "Xi-Baike", "name": { "family": "Xi", "given": "Baike" }, "orcid": "0000-0001-6126-2010" }, { "id": "Wu-Peng", "name": { "family": "Wu", "given": "Peng" }, "orcid": "0000-0001-7066-5487" }, { "id": "Logan-Timothy", "name": { "family": "Logan", "given": "Timothy" }, "orcid": "0000-0003-2648-1749" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Impacts of long-range transport of aerosols on marine-boundary-layer clouds in the eastern North Atlantic", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 Author(s) 2020. This work is distributed under the Creative Commons Attribution 4.0 License. \n\nReceived: 22 Jun 2020 \u2013 Discussion started: 27 Jul 2020 \u2013 Revised: 05 Oct 2020 \u2013 Accepted: 09 Oct 2020 \u2013 Published: 02 Dec 2020. \n\nThis article is part of the special issue \"Marine aerosols, trace gases, and clouds over the North Atlantic (ACP/AMT inter-journal SI)\". It is not associated with a conference. \n\nThis study was primarily supported by the collaborative NSF grant (award nos. AGS-1700727, 1700728). We acknowledge helpful discussions on the model setup with Zheng Lu at Texas A&M University. We thank the instrument mentors of the AMS, SP2, and CPC instruments and the individuals collecting measurements during the ACE-ENA field campaign. We also acknowledge high-performance computing support from Pleiades provided at NASA Ames. All requests for materials in this paper should be addressed to Yuan Wang (yuan.wang@caltech.edu). \n\nThis research has been supported by the National Science Foundation, Directorate for Geosciences (grant nos. AGS-1700727, AGS-1700728, and AGS-1700796). \n\nAuthor contributions. YW conceived and designed the research. YW performed the WRF simulations. YW and XZ performed the data analyses and produced the figures. YW wrote the paper. All authors contributed to the scientific discussions and preparation of the manuscript. \n\nData availability. All the WRF model simulation output used for this research can be downloaded from the corresponding author's website at http://web.gps.caltech.edu/~yzw/share/Wang-2020-ACP-Azores (Wang, 2020). The aircraft and ground-based measurements used in this study were obtained from the Atmospheric Radiation Measurement (ARM) program sponsored by the US Department of Energy (DOE) Office of Energy Research, Office of Health and Environmental Research, and Environmental Sciences Division. The data can be downloaded from https://adc.arm.gov/discovery/#/results/site_code::ena (Atmospheric Radiation Measurement Data Center, 2020). The CAMS global aerosol reanalysis product at pressure level used in this study can be downloaded at https://apps.ecmwf.int/datasets/data/cams-nrealtime/levtype=pl/ (European Centre for Medium-Range Weather Forecasts, 2020). ERA5 data are available for download via the data archive at the National Center for Atmospheric Research, Computational and Information Systems Laboratory (https://doi.org/10.5065/D6X34W69) (European Centre for Medium-Range Weather Forecasts, 2017). \n\nThe authors declare that they have no conflict of interest. \n\nReview statement. This paper was edited by Hailong Wang and reviewed by Michael Diamond and one anonymous referee.\n\nPublished - acp-20-14741-2020.pdf
", "abstract": "Vertical profiles of aerosols are inadequately observed and poorly represented in climate models, contributing to the current large uncertainty associated with aerosol\u2013cloud interactions. The US Department of Energy (DOE) Atmospheric Radiation Measurement (ARM) Aerosol and Cloud Experiments in the Eastern North Atlantic (ACE-ENA) aircraft field campaign near the Azores islands provided ample observations of vertical distributions of aerosol and cloud properties. Here we utilize the in situ aircraft measurements from the ACE-ENA and ground-based remote-sensing data along with an aerosol-aware Weather Research and Forecast (WRF) model to characterize the aerosols due to long-range transport over a remote region and to assess their possible influence on marine-boundary-layer (MBL) clouds. The vertical profiles of aerosol and cloud properties measured via aircraft during the ACE-ENA campaign provide detailed information revealing the physical contact between transported aerosols and MBL clouds. The European Centre for Medium-Range Weather Forecasts Copernicus Atmosphere Monitoring Service (ECMWF-CAMS) aerosol reanalysis data can reproduce the key features of aerosol vertical profiles in the remote region. The cloud-resolving WRF sensitivity experiments with distinctive aerosol profiles suggest that the transported aerosols and MBL cloud interactions (ACIs) require not only aerosol plumes to get close to the marine-boundary-layer top but also large cloud top height variations. Based on those criteria, the observations show that the occurrence of ACIs involving the transport of aerosol over the eastern North Atlantic (ENA) is about 62\u2009% in summer. For the case with noticeable long-range-transport aerosol effects on MBL clouds, the susceptibilities of droplet effective radius and liquid water content are \u22120.11 and +0.14, respectively. When varying by a similar magnitude, aerosols originating from the boundary layer exert larger microphysical influence on MBL clouds than those entrained from the free troposphere.", "date": "2020-12-02", "date_type": "published", "publication": "Atmospheric Chemistry and Physics", "volume": "20", "number": "23", "publisher": "European Geosciences Union", "pagerange": "14741-14755", "id_number": "CaltechAUTHORS:20210115-132721573", "issn": "1680-7324", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210115-132721573", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "AGS-1700727" }, { "agency": "NSF", "grant_number": "AGS-1700728" }, { "agency": "NSF", "grant_number": "AGS-1700796" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/acp-20-14741-2020", "primary_object": { "basename": "acp-20-14741-2020.pdf", "url": "https://authors.library.caltech.edu/records/p2aef-p8016/files/acp-20-14741-2020.pdf" }, "resource_type": "article", "pub_year": "2020", "author_list": "Wang, Yuan; Zheng, Xiaojian; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/57pm8-8cm79", "eprint_id": 104988, "eprint_status": "archive", "datestamp": "2023-08-22 07:44:44", "lastmod": "2023-10-20 21:01:55", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Li-Jiazheng", "name": { "family": "Li", "given": "Jiazheng" } }, { "id": "Gudipati-M-S", "name": { "family": "Gudipati", "given": "Murthy S." }, "orcid": "0000-0001-5992-373X" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "The influence of Europa's plumes on its atmosphere and ionosphere", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2020 Elsevier Inc. \n\nReceived 6 November 2019, Revised 21 July 2020, Accepted 21 July 2020, Available online 27 July 2020. \n\nWe thank D. Shemansky for useful discussions. This research was supported in part by an NSF grant to Caltech. MSG thanks JPL for support through the JPL-Campus JROC program. \n\nDeclaration of Competing Interest: None.\n\nPublished - 1-s2.0-S001910352030364X-main.pdf
", "abstract": "Europa, one of the Galilean satellites, has a tenuous, oxygen-dominated atmosphere that is usually referred to as a collision-less exosphere. Coupled to the neutral atmosphere and in contact with Europa's surface, a tenuous ionosphere exists on Europa, whose presence has been revealed by multiple observations. Such an ionosphere is thought to be produced by solar photoionization and electron-impact ionization of the oxygen in the atmosphere. However, a recent study showed that the maximum ionosphere coincides with intermittent water plume on Europa, suggesting that water plays an important role in the formation of the ionosphere. Based on the assumption of horizontal uniformity in the middle of the plume, we use the Caltech/Jet Propulsion Laboratory one-dimensional KINETICS model to construct profiles of neutral and ionized species near the plume region. The simulation results, which show that the ionization reactions are initiated by water electron-impact ionization and photoionization and continued by charge transfer between water and oxygen molecules, have successfully reproduced the observations. We find that H\u2082O\u207a is the dominant species only above the ionopause. Below the ionopause, the density of H\u2082O\u207a is orders of magnitude lower than the density of O\u2082\u207a, which is the major composition below the ionopause. Our model has also been used to study the dissociation processes of water molecules from the plumes, which can be regarded as an alternative source for the oxygen in the atmosphere.", "date": "2020-12", "date_type": "published", "publication": "Icarus", "volume": "352", "publisher": "Elsevier", "pagerange": "Art. No. 113999", "id_number": "CaltechAUTHORS:20200818-073830104", "issn": "0019-1035", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200818-073830104", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF" }, { "agency": "JPL" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/j.icarus.2020.113999", "primary_object": { "basename": "1-s2.0-S001910352030364X-main.pdf", "url": "https://authors.library.caltech.edu/records/57pm8-8cm79/files/1-s2.0-S001910352030364X-main.pdf" }, "resource_type": "article", "pub_year": "2020", "author_list": "Li, Jiazheng; Gudipati, Murthy S.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/652zz-b4y31", "eprint_id": 103229, "eprint_status": "archive", "datestamp": "2023-08-22 06:24:07", "lastmod": "2023-10-20 15:48:20", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Kim-Sang-Joon", "name": { "family": "Kim", "given": "Sang Joon" } }, { "id": "Sim-Chae-Kyung", "name": { "family": "Sim", "given": "Chae Kyung" } }, { "id": "Geballe-T-R", "name": { "family": "Geballe", "given": "Thomas R." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Miller-Steve", "name": { "family": "Miller", "given": "Steve" } }, { "id": "Greathouse-T-K", "name": { "family": "Greathouse", "given": "Thomas K." } }, { "id": "Lee-Sungho", "name": { "family": "Lee", "given": "Sungho" } }, { "id": "Tao-Chihiro", "name": { "family": "Tao", "given": "Chihiro" } } ] }, "title": "Temporal variation of the 3-micron hydrocarbon emissions at the 8-micron north polar hot spot of Jupiter: Comparison with solar wind activity", "ispublished": "pub", "full_text_status": "restricted", "keywords": "Jupiter, Infrared, Spectroscopy, Atmosphere, Aurora", "note": "\u00a9 2020 Elsevier Inc. \n\nReceived 25 July 2019, Revised 3 April 2020, Accepted 11 May 2020, Available online 15 May 2020. \n\nThis paper is based in large part on observations obtained at the Gemini Observatory, which is operated by the Association of Universities for Research in Astronomy, Inc., under a cooperative agreement with the NSF on behalf of the Gemini partnership: the National Science Foundation (United States), National Research Council (Canada), CONICYT (Chile), Ministerio de Ciencia, Tecnolog\u00eda e Innovaci\u00f3n Productiva (Argentina), Minist\u00e9rio da Ci\u00eancia, Tecnologia e Inova\u00e7\u00e3o (Brazil), and Korea Astronomy and Space Science Institute (Republic of Korea). SJK acknowledges support from the Basic Science Research Program (2018R1D1A1B07046476), and the Brain Korea 21 Plus (BK21+) program through NRF funded by the Ministry of Education, Science and Technology. SJK thanks a discussion with Prof. Gwang Son Choe regarding solar cycles, and useful information on collisional relaxation rates provided by Dr. Peter Panka. This research was supported by K-GMT Science Program (GN-2018A-Q-221) of Korea Astronomy and Space Science Institute. YLY acknowledges support by NASA New Frontiers Program. The solar wind data used in this study are available upon a request to C.Tao (chihiro.tao@nict.go.jp) and/or at AMDA database (http://amda.cdpp.eu). We thank the anonymous referees for their many detailed suggestions, which greatly improved the content of this paper.", "abstract": "We have obtained Gemini/GNIRS 3.3\u20133.4 \u03bcm spectra of Jupiter at 65o North latitude over a range of longitudes roughly centered on the 8-\u03bcm CH4 north polar hot spot (8CNPHS). The spectra were measured on four occasions during a four-month period in 2018, in order to search for variability of the 3-\u03bcm emissions of CH\u2084 and C\u2082H\u2086. The observed locations of the brightest spots of the C\u2082H\u2086 and CH\u2084 emissions at 65oN differed in longitude typically by 20o during this period. The peak emission intensities of these species showed large variations, with the highest intensities 3\u20134 times greater than the lowest intensities. In addition, the brightest 3-\u03bcm CH\u2084 emissions and hottest temperatures at the 8CNPHS were significantly less than those at the 3-\u03bcm CH4 north polar hot spot (3CNPHS, Kim et al., 2015). Recently, Sinclair et al. (2019) reported a coincidence between solar wind dynamical pressure and the 8-\u03bcm brightening of the 8CNPHS. In contrast, we find lack of correlation in our data between the 3-\u03bcm hydrocarbon emission intensities at the 8CNPHS and the solar wind strength. We also find lack of correlation between H\u2083\u207a intensities and the solar wind strength during the period. However, due to the limited observational data, it is too early to conclude whether this lack of correlation indicates that the solar wind activity induced no significant changes in local temperatures (<40 K) and/or mixing ratios of these molecules. Our observing period was close to the historic grand solar minimum. The detailed influence of the solar activity on the 3 and 8 \u03bcm brightness at the 8CNPHS is not quantitatively understood at the present time.", "date": "2020-09-15", "date_type": "published", "publication": "Icarus", "volume": "348", "publisher": "Elsevier", "pagerange": "Art. No. 113852", "id_number": "CaltechAUTHORS:20200515-091955895", "issn": "0019-1035", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200515-091955895", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Gemini Partnership" }, { "agency": "National Research Foundation of Korea", "grant_number": "2018R1D1A1B07046476" }, { "agency": "Brain Korea 21 Plus Program" }, { "agency": "Ministry of Education, Science and Technology (Korea)" }, { "agency": "Korea Astronomy and Space Science Institute (KASI)", "grant_number": "GN-2018A-Q-221" }, { "agency": "NASA" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/j.icarus.2020.113852", "resource_type": "article", "pub_year": "2020", "author_list": "Kim, Sang Joon; Sim, Chae Kyung; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/ynjp7-1r804", "eprint_id": 104995, "eprint_status": "archive", "datestamp": "2023-08-22 06:08:29", "lastmod": "2023-10-20 21:16:17", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Teng-Shiwen", "name": { "family": "Teng", "given": "Shiwen" }, "orcid": "0000-0003-3436-7882" }, { "id": "Liu-Chao", "name": { "family": "Liu", "given": "Chao" }, "orcid": "0000-0001-7049-493X" }, { "id": "Zhang-Zhibo", "name": { "family": "Zhang", "given": "Zhibo" }, "orcid": "0000-0001-9491-1654" }, { "id": "Wang-Yuan", "name": { "family": "Wang", "given": "Yuan" }, "orcid": "0000-0001-6657-8401" }, { "id": "Sohn-Byung\u2010Ju", "name": { "family": "Sohn", "given": "Byung\u2010Ju" }, "orcid": "0000-0001-6134-3515" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Retrieval of Ice-Over-Water Cloud Microphysical and Optical Properties Using Passive Radiometers", "ispublished": "pub", "full_text_status": "public", "keywords": "Cloud Properties; Satellite Radiameter; Vertical distribution", "note": "\u00a9 2020 American Geophysical Union. \n\nIssue Online: 19 August 2020; Version of Record online: 19 August 2020; Accepted manuscript online: 06 August 2020; Manuscript accepted: 28 July 2020; Manuscript revised: 23 July 2020; Manuscript received: 19 May 2020. \n\nWe acknowledge the funding support by the National Natural Science Foundation of China (41975025), the National Key Research and Development Program of China (2018YFC1506502), the Natural Science Foundation of Jiangsu Province (BK20190093), and the Postgraduate Research and Practice Innovation Program of Jiangsu Province (KYCX20_0926).\n\nPublished - 2020GL088941.pdf
Supplemental Material - grl61044-sup-0001-2020gl088941-si.docx
", "abstract": "Current satellite cloud products from passive radiometers provide effective single\u2010layer cloud properties by assuming a homogeneous cloud in a pixel, resulting in inevitable biases when multiple\u2010layer clouds are present in a vertical column. We devise a novel method to retrieve cloud vertical properties for ice\u2010over\u2010water clouds using passive radiometers. Based on the absorptivity differences of liquid water and ice clouds at four shortwave\u2010infrared channels (centered at 0.87, 1.61, 2.13, and 2.25 \u03bcm), cloud optical thicknesses (COT) and effective radii of both upper\u2010layer ice and lower\u2010layer liquid water clouds are inferred simultaneously. The algorithm works most effectively for clouds with ice COT < 7 and liquid water COT > 5. The simulated spectral reflectances based on our retrieved ice\u2010over\u2010water clouds become more consistent with observations than those with a single\u2010layer assumption. This new algorithm will improve our understanding of clouds, and we suggest that these four cloud channels should be all included in future satellite sensors.", "date": "2020-08-28", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "47", "number": "16", "publisher": "American Geophysical Union", "pagerange": "Art. No. e2020GL088941", "id_number": "CaltechAUTHORS:20200818-102949818", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200818-102949818", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "National Natural Science Foundation of China", "grant_number": "41975025" }, { "agency": "National Key Research and Development Program of China", "grant_number": "2018YFC1506502" }, { "agency": "Natural Science Foundation of Jiangsu Province", "grant_number": "BK20190093" }, { "agency": "Postgraduate Research and Practice Innovation Program of Jiangsu Province", "grant_number": "KYCX20_0926" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2020gl088941", "primary_object": { "basename": "2020GL088941.pdf", "url": "https://authors.library.caltech.edu/records/ynjp7-1r804/files/2020GL088941.pdf" }, "related_objects": [ { "basename": "grl61044-sup-0001-2020gl088941-si.docx", "url": "https://authors.library.caltech.edu/records/ynjp7-1r804/files/grl61044-sup-0001-2020gl088941-si.docx" } ], "resource_type": "article", "pub_year": "2020", "author_list": "Teng, Shiwen; Liu, Chao; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/6e46y-xz920", "eprint_id": 103957, "eprint_status": "archive", "datestamp": "2023-08-19 22:53:00", "lastmod": "2023-10-20 16:53:04", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Le-Tianhao", "name": { "family": "Le", "given": "Tianhao" }, "orcid": "0000-0002-6600-8270" }, { "id": "Wang-Yuan", "name": { "family": "Wang", "given": "Yuan" }, "orcid": "0000-0001-6657-8401" }, { "id": "Liu-Lang", "name": { "family": "Liu", "given": "Lang" }, "orcid": "0000-0002-1092-0615" }, { "id": "Yang-Jiani", "name": { "family": "Yang", "given": "Jiani" } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Li-Guohui", "name": { "family": "Li", "given": "Guohui" } }, { "id": "Seinfeld-J-H", "name": { "family": "Seinfeld", "given": "John H." }, "orcid": "0000-0003-1344-4068" } ] }, "title": "Unexpected air pollution with marked emission reductions during the COVID-19 outbreak in China", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2020 The Authors. This work is licensed under a Creative Commons Attribution 4.0 International (CC BY 4.0) license, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. To view a copy of this license, visit https://creativecommons.org/licenses/by/4.0/. This license does not apply to figures/photos/artwork or other content included in the article that is credited to a third party; obtain authorization from the rights holder before using such material. \n\nReceived for publication March 16, 2020. Accepted for publication June 9, 2020. \n\nWe are grateful to Chao Liu and Alexei Lyapustin for helpful discussions on the satellite products, and Yuxuan Wang and Yuanlong Huang for chemistry analysis. \n\nY.W. and Y.L.Y. acknowledge the support of the Jet Propulsion Laboratory, California Institute of Technology, under contract with NASA. Additional support was provided by the NSF AGS-1700727 grant. G.L. and L.L. acknowledge the National Key R&D Plan Grant 2017YFC0210000 and the Strategic Priority Research Program of Chinese Academy of Sciences Grant XDB40030203. \n\nAuthor contributions: Y.W. conceived and designed the research. T.L., Y.W., and Y.L.Y. performed the data analyses and produced the figures. L.L, Y.W., and G.L. performed and analyzed the WRF-Chem simulations. J.Y. and L.L. obtained the ground-based pollution data. Y.W. and J.H.S wrote the paper. All authors contributed to the scientific discussions and preparation of the manuscript. \n\nThe authors declare no competing interests. \n\nData and materials availability: All data are available in the manuscript or the supplementary materials.\n\nPublished - 702.full.pdf
Supplemental Material - abb7431_Le_SM.pdf
", "abstract": "The absence of motor vehicle traffic and suspended manufacturing during the coronavirus disease 2019 (COVID-19) pandemic in China enabled assessment of the efficiency of air pollution mitigation. Up to 90% reduction of certain emissions during the city-lockdown period can be identified from satellite and ground-based observations. Unexpectedly, extreme particulate matter levels simultaneously occurred in northern China. Our synergistic observation analyses and model simulations show that anomalously high humidity promoted aerosol heterogeneous chemistry, along with stagnant airflow and uninterrupted emissions from power plants and petrochemical facilities, contributing to severe haze formation. Also, because of nonlinear production chemistry and titration of ozone in winter, reduced nitrogen oxides resulted in ozone enhancement in urban areas, further increasing the atmospheric oxidizing capacity and facilitating secondary aerosol formation.", "date": "2020-08-07", "date_type": "published", "publication": "Science", "volume": "369", "number": "6504", "publisher": "American Association for the Advancement of Science", "pagerange": "702-706", "id_number": "CaltechAUTHORS:20200622-104138262", "issn": "0036-8075", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200622-104138262", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA/JPL/Caltech" }, { "agency": "NSF", "grant_number": "AGS-1700727" }, { "agency": "National Key Research and Development Program of China", "grant_number": "2017YFC0210000" }, { "agency": "Chinese Academy of Sciences", "grant_number": "XDB40030203" } ] }, "local_group": { "items": [ { "id": "Astronomy-Department" }, { "id": "COVID-19" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1126/science.abb7431", "primary_object": { "basename": "abb7431_Le_SM.pdf", "url": "https://authors.library.caltech.edu/records/6e46y-xz920/files/abb7431_Le_SM.pdf" }, "related_objects": [ { "basename": "702.full.pdf", "url": "https://authors.library.caltech.edu/records/6e46y-xz920/files/702.full.pdf" } ], "resource_type": "article", "pub_year": "2020", "author_list": "Le, Tianhao; Wang, Yuan; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/v253h-5yj75", "eprint_id": 107186, "eprint_status": "archive", "datestamp": "2023-08-22 05:18:10", "lastmod": "2023-10-23 15:37:53", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Liu-Chao", "name": { "family": "Liu", "given": "Chao" }, "orcid": "0000-0001-7049-493X" }, { "id": "Yao-Bin", "name": { "family": "Yao", "given": "Bin" } }, { "id": "Natraj-Vijay", "name": { "family": "Natraj", "given": "Vijay" }, "orcid": "0000-0003-3154-9429" }, { "id": "Weng-Fuzhong", "name": { "family": "Weng", "given": "Fuzhong" } }, { "id": "Le-Tianhao", "name": { "family": "Le", "given": "Tianhao" }, "orcid": "0000-0002-6600-8270" }, { "id": "Shia-Run-Lie", "name": { "family": "Shia", "given": "Run-Lie" }, "orcid": "0000-0003-1911-3120" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "A Spectral Data Compression (SDCOMP) Radiative Transfer Model for High-Spectral-Resolution Radiation Simulations", "ispublished": "pub", "full_text_status": "public", "keywords": "Radiative transfer; Remote sensing", "note": "\u00a9 2020 American Meteorological Society. \n\nPublished-online: 26 May 2020; Print Publication: 01 Jun 2020. \n\nThis research was supported in part by the National Natural Science Foundation of China (NSFC) (41975025) and the Young Elite Scientists Sponsorship Program of CAST (2017NRC001). A portion of this research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration (80NM0018D0004). V. N. acknowledges support from the NASA Earth Science U.S. Participating Investigator program (Solicitation NNH16ZDA001N-ESUSPI).\n\n", "abstract": "With the increasing use of satellite and ground-based high-spectral-resolution (HSR) measurements for weather and climate applications, accurate and efficient radiative transfer (RT) models have become essential for accurate atmospheric retrievals, for instrument calibration, and to provide benchmark RT solutions. This study develops a spectral data compression (SDCOMP) RT model to simulate HSR radiances in both solar and infrared spectral regions. The SDCOMP approach \"compresses\" the spectral data in the optical property and radiance domains, utilizing principal component analysis (PCA) twice to alleviate the computational burden. First, an optical-property-based PCA is performed for a given atmospheric scenario (atmospheric, trace gas, and aerosol profiles) to simulate relatively low-spectral-resolution radiances at a small number of representative wavelengths. Second, by using precalculated principal components from an accurate radiance dataset computed for a large number of atmospheric scenarios, a radiance-based PCA is carried out to extend the low-spectral-resolution results to desired HSR results at all wavelengths. This procedure ensures both that individual monochromatic RT calculations are efficiently performed and that the number of such computations is optimized. SDCOMP is approximately three orders of magnitude faster than numerically exact RT calculations. The resulting monochromatic radiance has relative errors less than 0.2% in the solar region and brightness temperature differences less than 0.1 K for over 95% of the cases in the infrared region. The efficiency and accuracy of SDCOMP not only make it useful for analysis of HSR measurements, but also hint at the potential for utilizing this model to perform RT simulations in mesoscale numerical weather and general circulation models.", "date": "2020-06-01", "date_type": "published", "publication": "Journal of the Atmospheric Sciences", "volume": "77", "number": "6", "publisher": "American Meteorological Society", "pagerange": "2055-2066", "id_number": "CaltechAUTHORS:20201218-085922809", "issn": "0022-4928", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201218-085922809", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "National Natural Science Foundation of China", "grant_number": "41975025" }, { "agency": "China Association for Science and Technology", "grant_number": "2017NRC001" }, { "agency": "NASA", "grant_number": "80NM0018D0004" }, { "agency": "NASA/JPL/Caltech" }, { "agency": "NASA", "grant_number": "NNH16ZDA001N-ESUSPI" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1175/jas-d-19-0238.1", "primary_object": { "basename": "_15200469_-_Journal_of_Atmospheric_Sciences__A_Spectral_Data_Compression__SDCOMP__Radiative_Transfer_Model_for_High-Spectral-Resolution_Radiation_Simulations.pdf", "url": "https://authors.library.caltech.edu/records/v253h-5yj75/files/_15200469_-_Journal_of_Atmospheric_Sciences__A_Spectral_Data_Compression__SDCOMP__Radiative_Transfer_Model_for_High-Spectral-Resolution_Radiation_Simulations.pdf" }, "resource_type": "article", "pub_year": "2020", "author_list": "Liu, Chao; Yao, Bin; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/y8k0n-f9z97", "eprint_id": 101998, "eprint_status": "archive", "datestamp": "2023-08-22 05:16:41", "lastmod": "2023-10-19 23:43:40", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Zeng-Zhao-Cheng", "name": { "family": "Zeng", "given": "Zhao-Cheng" }, "orcid": "0000-0002-0008-6508" }, { "id": "Xu-Feng", "name": { "family": "Xu", "given": "Feng" }, "orcid": "0000-0001-5155-9478" }, { "id": "Natraj-V", "name": { "family": "Natraj", "given": "Vijay" }, "orcid": "0000-0003-3154-9429" }, { "id": "Pongetti-T-J", "name": { "family": "Pongetti", "given": "Thomas J." }, "orcid": "0000-0001-9465-0853" }, { "id": "Shia-Run-Lie", "name": { "family": "Shia", "given": "Run-Lie" }, "orcid": "0000-0003-1911-3120" }, { "id": "Zhang-Qiong", "name": { "family": "Zhang", "given": "Qiong" }, "orcid": "0000-0002-8762-0557" }, { "id": "Sander-S-P", "name": { "family": "Sander", "given": "Stanley P." }, "orcid": "0000-0003-1424-3620" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Remote sensing of angular scattering effect of aerosols in a North American megacity", "ispublished": "pub", "full_text_status": "public", "keywords": "Aerosol scattering; Angular dependence; Urban remote sensing; Megacity; CLARS", "note": "\u00a9 2020 Elsevier Inc. \n\nReceived 26 June 2019, Revised 27 February 2020, Accepted 9 March 2020, Available online 18 March 2020. \n\nWe thank the reviewers for their constructive comments and suggestions that helped improve the manuscript. The CLARS project receives support from the California Air Resources Board and the NIST GHG and Climate Science Program. V. N. acknowledges support from the NASA Earth Science Division US Participating Investigator program (solicitation NNH16ZDA001N-ESUSPI). F. X. acknowledges support from the NASA Remote Sensing Theory program under grant 14-RST14-0100. We are also thankful for the support from the Jet Propulsion Laboratory Research and Technology Development Program. AERONET data for the Caltech site are available from https://aeronet.gsfc.nasa.gov/new_web/photo_db_v3/CalTech.html. We also thank Jochen Stutz from UCLA and his staff for their effort in establishing and maintaining the AERONET Caltech site. MERRAero is available from NASA GMAO at https://gmao.gsfc.nasa.gov/reanalysis/MERRA/. CLARS-FTS data are available from the authors upon request, and part of the data are available from the NASA Megacities Project at https://megacities.jpl.nasa.gov. A portion of this research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration. Z. C. Zeng would like to dedicate this paper to his newborn daughter Judith Zeng. \n\nCredit author statement:\nZ.-C. Zeng: Conceptualization, Methodology, Software, Writing-Original draft preparation;\nF. Xu: Software, Validation, Methodology;\nV. Natraj: Software, Validation, Writing - Review & Editing;\nT. Pongetti: Data curation;\nR.-L. Shia: Software, Validation;\nQ. Zhang: Software, Validation;\nS. Sander: Supervision;\nY. Yung: Supervision. \n\nThe authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.\n\nSubmitted - 1907.07823.pdf
", "abstract": "The angle-dependent scattering effect of aerosols in the atmosphere not only influences climate through radiative forcing effects but also impacts trace gas remote sensing by modifying the path of radiation through the atmosphere. The aerosol phase function, which characterizes the angular signature of scattering, has been continuously monitored from ground-based and space-borne observations. However, the range of scattering angles these instruments can sample is very limited. Here, we report multi-year measurements from a mountain-top remote sensing instrument: the California Laboratory for Atmospheric Remote Sensing Fourier Transform Spectrometer (CLARS-FTS), which overlooks the Los Angeles megacity. The observational geometries of CLARS-FTS provide a wide range of scattering angles, from about 20\u00b0 (forward) to about 140\u00b0 (backward), which is larger than the range provided by any existing aerosol remote sensing instrument. We then quantify the aerosol angular scattering effect using the O\u2082 ratio, which is the ratio of retrieved O\u2082 Slant Column Density (SCD) to geometric O\u2082 SCD. The O\u2082 ratio quantifies the light path modification due to aerosol scattering, with a value of 1 representing an aerosol-free scenario. The lower the O\u2082 ratio value than 1, the stronger the aerosol loading. CLARS-FTS measurements are highly sensitive to the angular scattering effect of aerosols in the Los Angeles (LA) urban atmosphere, due to the long light path going through the boundary layer and the wide range of observational angles. The differences in aerosol scattering between different surface reflection points targeted by CLARS-FTS can be explained by differences in their angular scattering geometries. The correlation between measurements at different targets can be used to quantify the strength of the angular dependence of the aerosol phase function. Applying the correlation technique to CLARS-FTS measurements, we find that, from 2011 to 2018, there is no significant trend in the aerosol phase function in the LA megacity. Overall, this study provides a practical observing strategy for quantifying the angular dependence of aerosol scattering in urban atmospheres that could potentially contribute towards improved greenhouse gas remote sensing in megacities.", "date": "2020-06-01", "date_type": "published", "publication": "Remote Sensing of Environment", "volume": "242", "publisher": "Elsevier", "pagerange": "Art. No. 111760", "id_number": "CaltechAUTHORS:20200319-123810926", "issn": "0034-4257", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200319-123810926", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "California Air Resources Board" }, { "agency": "National Institute of Standards and Technology (NIST)" }, { "agency": "NASA", "grant_number": "NNH16ZDA001N-ESUSPI" }, { "agency": "NASA", "grant_number": "14-RST14-0100" }, { "agency": "JPL Research and Technology Development Fund" }, { "agency": "NASA/JPL/Caltech" } ] }, "local_group": { "items": [ { "id": "Astronomy-Department" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/j.rse.2020.111760", "primary_object": { "basename": "1907.07823.pdf", "url": "https://authors.library.caltech.edu/records/y8k0n-f9z97/files/1907.07823.pdf" }, "resource_type": "article", "pub_year": "2020", "author_list": "Zeng, Zhao-Cheng; Xu, Feng; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/6qymz-gm142", "eprint_id": 103578, "eprint_status": "archive", "datestamp": "2023-08-19 21:31:10", "lastmod": "2023-10-20 16:30:45", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Fan-Siteng", "name": { "family": "Fan", "given": "Siteng" }, "orcid": "0000-0002-3041-4680" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Surface Mapping of Earth-like Exoplanets using Single Point Light Curves", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2020 Journal of Visualized Experiments. \n\nPublished: 5/10/2020. \n\nThis work was partly supported by the Jet Propulsion Laboratory, California Institute of Technology, under contract with NASA. YLY acknowledge support by the Virtual Planetary Laboratory at the University of Washington. \n\nThe authors have nothing to disclose.\n\nSupplemental Material - jove-materials-60951-surface-mapping-earth-like-exoplanets-using-single-point-light.pdf
", "abstract": "Spatially resolving exoplanet features from single-point observations is essential for evaluating the potential habitability of exoplanets. The ultimate goal of this protocol is to determine whether these planetary worlds harbor geological features and/or climate systems. We present a method of extracting information from multi-wavelength single-point light curves and retrieving surface maps. It uses singular value decomposition (SVD) to separate sources that contribute to light curve variations and infer the existence of partially cloudy climate systems. Through analysis of the time series obtained from SVD, physical attributions of principal components (PCs) could be inferred without assumptions of any spectral properties. Combining with viewing geometry, it is feasible to reconstruct surface maps if one of the PCs are found to contain surface information. Degeneracy originated from convolution of the pixel geometry and spectrum information determines the quality of reconstructed surface maps, which requires the introduction of regularization. For the purpose of demonstrating the protocol, multi-wavelength light curves of Earth, which serves as a proxy exoplanet, are analyzed. Comparison between the results and the ground truth is presented to show the performance and limitation of the protocol. This work provides a benchmark for future generalization of exoplanet applications.", "date": "2020-05-22", "date_type": "published", "publication": "Journal of Visualized Experiments", "volume": "2020", "number": "159", "publisher": "Journal of Visualized Experiments", "pagerange": "Art. No. e60951", "id_number": "CaltechAUTHORS:20200601-084051044", "issn": "1940-087X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200601-084051044", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA/JPL/Caltech" }, { "agency": "University of Washington" } ] }, "local_group": { "items": [ { "id": "Astronomy-Department" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.3791/60951", "primary_object": { "basename": "jove-materials-60951-surface-mapping-earth-like-exoplanets-using-single-point-light.pdf", "url": "https://authors.library.caltech.edu/records/6qymz-gm142/files/jove-materials-60951-surface-mapping-earth-like-exoplanets-using-single-point-light.pdf" }, "resource_type": "article", "pub_year": "2020", "author_list": "Fan, Siteng and Yung, Yuk L." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/5c31y-e4q11", "eprint_id": 103109, "eprint_status": "archive", "datestamp": "2023-08-22 05:02:01", "lastmod": "2023-10-20 15:39:21", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Li-Chong", "name": { "family": "Li", "given": "Chong" }, "orcid": "0000-0002-1177-3805" }, { "id": "Li-Jing", "name": { "family": "Li", "given": "Jing" }, "orcid": "0000-0002-0540-0412" }, { "id": "Dubovik-O", "name": { "family": "Dubovik", "given": "Oleg" }, "orcid": "0000-0003-3482-6460" }, { "id": "Zeng-Zhao-Cheng", "name": { "family": "Zeng", "given": "Zhao-Cheng" }, "orcid": "0000-0002-0008-6508" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Impact of Aerosol Vertical Distribution on Aerosol Optical Depth Retrieval from Passive Satellite Sensors", "ispublished": "pub", "full_text_status": "public", "keywords": "aerosol vertical distribution; aerosol optical depth; satellite AOD retrieval", "note": "\u00a9 2020 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/). \n\nReceived: 9 April 2020; Accepted: 5 May 2020; Published: 11 May 2020. \n\nThe authors gratefully appreciate the AERONET site principal investigators for providing and maintaining the ground-based measurements and data can be found online at http://aeronet.gsfc.nasa.gov. We'd like to acknowledge the VIIRS Team for freely distributed data which can be accessed from NOAA Comprehensive Large Array-Data Stewardship System at https://www.bou.class.noaa.gov/. We are also grateful to the developers of 6SV and MODTRAN radiative transfer models. O. Dubovik was supported by the CaPPA Project (Chemical and Physical Properties of the Atmosphere) that is funded by the French National Research Agency (ANR) through the PIA (Programme d'Investissement d'Avenir) under contract \"ANR-11-LABX-0005-01\" and by the Regional Council \"Nord Pas de Calais-Picardie\" and the European Funds for Regional Economic Development. C. Li was supported by the China Scholarship Council for 1 year study at the Universit\u00e9 Lille-1.\n\nAuthor Contributions:\nConceptualization, J.L.; methodology, C.L., J.L., O.D., Z.-C.Z., Y.L.Y.; investigation, C.L.; writing\u2014original draft preparation, C.L.; writing\u2014review and editing, J.L., O.D., Z.-C.Z., Y.L.Y.; visualization, C.L.; supervision, J.L.; All authors have read and agreed to the published version of the manuscript. \n\nThis research was funded by Nation Natural Science Foundation of China No. 41975023 and the National Key Research and Development Program of China No. 2017YFC0212803. \n\nThe authors declare no conflict of interest.\n\nPublished - remotesensing-12-01524.pdf
", "abstract": "When retrieving Aerosol Optical Depth (AOD) from passive satellite sensors, the vertical distribution of aerosols usually needs to be assumed, potentially causing uncertainties in the retrievals. In this study, we use the Moderate Resolution Spectroradiometer (MODIS) and Visible Infrared Imaging Radiometer Suite (VIIRS) sensors as examples to investigate the impact of aerosol vertical distribution on AOD retrievals. A series of sensitivity experiments was conducted using radiative transfer models with different aerosol profiles and surface conditions. Assuming a 0.2 AOD, we found that the AOD retrieval error is the most sensitive to the vertical distribution of absorbing aerosols; a \u22121 km error in aerosol scale height can lead to a ~30% AOD retrieval error. Moreover, for this aerosol type, ignoring the existence of the boundary layer can further result in a ~10% AOD retrieval error. The differences in the vertical distribution of scattering and absorbing aerosols within the same column may also cause \u221215% (scattering aerosols above absorbing aerosols) to 15% (scattering aerosols below absorbing aerosols) errors. Surface reflectance also plays an important role in affecting the AOD retrieval error, with higher errors over brighter surfaces in general. The physical mechanism associated with the AOD retrieval errors is also discussed. Finally, by replacing the default exponential profile with the observed aerosol vertical profile by a micro-pulse lidar at the Beijing-PKU site in the VIIRS retrieval algorithm, the retrieved AOD shows a much better agreement with surface observations, with the correlation coefficient increased from 0.63 to 0.83 and bias decreased from 0.15 to 0.03. Our study highlights the importance of aerosol vertical profile assumption in satellite AOD retrievals, and indicates that considering more realistic profiles can help reduce the uncertainties.", "date": "2020-05-11", "date_type": "published", "publication": "Remote Sensing", "volume": "12", "number": "9", "publisher": "MDPI", "pagerange": "Art. No. 1524", "id_number": "CaltechAUTHORS:20200511-132935776", "issn": "2072-4292", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200511-132935776", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "National Natural Science Foundation of China", "grant_number": "41975023" }, { "agency": "National Key Research and Development Program of China", "grant_number": "2017YFC0212803" } ] }, "local_group": { "items": [ { "id": "Astronomy-Department" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.3390/rs12091524", "primary_object": { "basename": "remotesensing-12-01524.pdf", "url": "https://authors.library.caltech.edu/records/5c31y-e4q11/files/remotesensing-12-01524.pdf" }, "resource_type": "article", "pub_year": "2020", "author_list": "Li, Chong; Li, Jing; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/4fbd0-qm594", "eprint_id": 101698, "eprint_status": "archive", "datestamp": "2023-08-22 04:51:06", "lastmod": "2023-10-19 22:57:40", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Le-Tianhao", "name": { "family": "Le", "given": "Tianhao" } }, { "id": "Liu-Chao", "name": { "family": "Liu", "given": "Chao" }, "orcid": "0000-0001-7049-493X" }, { "id": "Yao-Bin", "name": { "family": "Yao", "given": "Bin" } }, { "id": "Natraj-V", "name": { "family": "Natraj", "given": "Vijay" }, "orcid": "0000-0003-3154-9429" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Application of Machine Learning to Hyperspectral Radiative Transfer Simulations", "ispublished": "pub", "full_text_status": "public", "keywords": "Radiative transfer; hyperspectral; machine learning; principal component analysis", "note": "\u00a9 2020 Elsevier Ltd. \n\nReceived 30 September 2019, Revised 4 January 2020, Accepted 22 February 2020, Available online 28 February 2020.", "abstract": "Hyperspectral observations have become one of the most popular and powerful methods for atmospheric remote sensing, and are widely used for temperature, gas, aerosol, and cloud retrievals. However, accurate forward radiative transfer simulations are computationally expensive since typical line-by-line approaches involve a larger number of monochromatic radiative transfer calculations. This study explores the feasibility of machine learning techniques for fast hyperspectral radiative transfer (HRT) simulations, which essentially performs calculations at a small fraction of hyperspectral wavelengths and extends them across the entire spectral range. A neural network (NN) model is used as an example for the development of the fast HRT, and its results are compared with those from a principal component analysis (PCA) model, which shares a similar principle. We consider hyperspectral radiances from both actual satellite observations and accurate line-by-line simulations. The NN model can alleviate the computational burden by two to three orders of magnitude, and generates radiances with small relative errors (generally less than 0.5% compared to exact calculations); the performance of the NN model is better than that of the PCA model. The model can be further improved by optimizing the training procedure and parameters, the representative wavelengths, and the machine learning technique itself.", "date": "2020-05", "date_type": "published", "publication": "Journal of Quantitative Spectroscopy and Radiative Transfer", "volume": "246", "publisher": "Elsevier", "pagerange": "Art. No. 106928", "id_number": "CaltechAUTHORS:20200304-091512556", "issn": "0022-4073", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200304-091512556", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "local_group": { "items": [ { "id": "Astronomy-Department" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/j.jqsrt.2020.106928", "resource_type": "article", "pub_year": "2020", "author_list": "Le, Tianhao; Liu, Chao; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/5yrmz-59763", "eprint_id": 102404, "eprint_status": "archive", "datestamp": "2023-08-22 04:25:47", "lastmod": "2023-10-20 00:10:14", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Wang-Yuan", "name": { "family": "Wang", "given": "Yuan" }, "orcid": "0000-0001-6657-8401" }, { "id": "Su-Hui", "name": { "family": "Su", "given": "Hui" }, "orcid": "0000-0003-1265-9702" }, { "id": "Jiang-Jonathan-H", "name": { "family": "Jiang", "given": "Jonathan H." }, "orcid": "0000-0002-5929-8951" }, { "id": "Xu-Feng", "name": { "family": "Xu", "given": "Feng" }, "orcid": "0000-0001-5155-9478" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Impact of Cloud Ice Particle Size Uncertainty in a Climate Model and Implications for Future Satellite Missions", "ispublished": "pub", "full_text_status": "public", "keywords": "ice clouds; climate modeling; climate sensitivity; ice effective radius", "note": "\u00a9 2020 American Geophysical Union. \n\nReceived 26 NOV 2019; Accepted 5 MAR 2020; Accepted article online 10 MAR 2020. \n\nThis work was conducted at the NASA\u2010sponsored Jet Propulsion Laboratory (JPL), California Institute of Technology. All the climate model simulate output used for this research can be downloaded from this website (http://web.gps.caltech.edu/~yzw/share/Wang\u20102020\u2010JGR\u2010Ice/). The code of NCAR CESM model used in this study is available at this site (http://www2.mmm.ucar.edu/wrf/users/download/get_source.html). We also acknowledge high\u2010performance computing support from Pleiades provided at NASA Ames. All requests for materials in this paper should be addressed to Yuan Wang (yuan.wang@caltech.edu).\n\nPublished - 2019JD032119.pdf
", "abstract": "Ice particle size is pivotal to determining ice cloud radiative effect and precipitating rate. However, there is a lack of accurate ice particle effective radius (R_(ei)) observation on the global scale to constrain its representation in climate models. In support of future mission design, here we present a modeling assessment of the sensitivity of climate simulations to R_(ei) and quantify the impact of the proposed mission concept on reducing the uncertainty in climate sensitivity. We perturb the parameters pertaining to ice fall speed parameter and R_(ei) in radiation scheme, respectively, in National Center for Atmospheric Research CESM1 model with a slab ocean configuration. The model sensitivity experiments show that a settling velocity increase due to a larger R_(ei) results in a longwave cooling dominating over a shortwave warming, a global mean surface temperature decrease, and precipitation suppression. A similar competition between longwave and shortwave cloud forcing changes also exists when perturbing R_(ei) in the radiation scheme. Linearity generally holds for the climate response for R_(ei) related parameters. When perturbing falling snow particle size (R_(es)) in a similar way, we find much less sensitivity of climate responses. Our quadrupling CO\u2082 experiments with different parameter settings reveal that R_(ei) and R_(es) can account for changes in climate sensitivity significantly from +12.3% to \u22126.2%. By reducing the uncertainty ranges of R_(ei) and R_(es) from a factor of 2 to \u00b125%, a future satellite mission under design is expected to improve the climate state simulations and reduce the climate sensitivity uncertainty pertaining to ice particle size by approximately 60%. Our results highlight the importance of better observational constraints on R_(ei) by satellite missions.", "date": "2020-03-27", "date_type": "published", "publication": "Journal of Geophysical Research. Atmospheres", "volume": "125", "number": "6", "publisher": "American Geophysical Union", "pagerange": "Art. No. e2019JD032119", "id_number": "CaltechAUTHORS:20200408-132401922", "issn": "2169-897X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200408-132401922", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA/JPL/Caltech" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2019jd032119", "primary_object": { "basename": "2019JD032119.pdf", "url": "https://authors.library.caltech.edu/records/5yrmz-59763/files/2019JD032119.pdf" }, "resource_type": "article", "pub_year": "2020", "author_list": "Wang, Yuan; Su, Hui; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/7vyx7-sv944", "eprint_id": 100403, "eprint_status": "archive", "datestamp": "2023-08-22 04:09:54", "lastmod": "2023-10-23 16:12:26", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Wang-Yuan", "name": { "family": "Wang", "given": "Yuan" }, "orcid": "0000-0001-6657-8401" }, { "id": "Le-Tianhao", "name": { "family": "Le", "given": "Tianhao" } }, { "id": "Chen-Gang", "name": { "family": "Chen", "given": "Gang" } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Su-Hui", "name": { "family": "Su", "given": "Hui" }, "orcid": "0000-0003-1265-9702" }, { "id": "Seinfeld-J-H", "name": { "family": "Seinfeld", "given": "John H." }, "orcid": "0000-0003-1344-4068" }, { "id": "Jiang-Jonathan-H", "name": { "family": "Jiang", "given": "Jonathan H." }, "orcid": "0000-0002-5929-8951" } ] }, "title": "Reduced European aerosol emissions suppress winter extremes over northern Eurasia", "ispublished": "pub", "full_text_status": "public", "keywords": "Atmospheric chemistry; Atmospheric dynamics", "note": "\u00a9 The Author(s), under exclusive licence to Springer Nature Limited 2020. \n\nReceived: 12 July 2019; Accepted: 7 January 2020; Published 3 February 2020. \n\nThis study is supported by the NASA ROSES ACMAP and CCST, and NSF grants AGS-1700727 and AGS-1742178. We acknowledge the support of the Jet Propulsion Laboratory, California Institute of Technology, under contract with NASA. We also acknowledge high-performance computing support from Pleiades, provided at NASA Ames. The CESM project is supported primarily by the National Science Foundation. All correspondence and requests for materials should be addressed to Y.W. (yuan.wang@caltech.edu). \n\nData availability: The reanalysis products used in this study are publicly available from the NCAR Research Data Archive (https://rda.ucar.edu/datasets/ds628.0/). Monthly mean climate indices are available from the NOAA Climate Prediction Center (https://www.esrl.noaa.gov/psd/data/climateindices/list/). \n\nCode availability: The code of the NCAR CESM model used in this study is available at http://www2.mmm.ucar.edu/wrf/users/download/get_source.html. The scripts used to process the model data can be found on the public website of corresponding author Y.W. (http://web.gps.caltech.edu/~yzw/share/Wang-2020-NCC). \n\nThe authors declare no competing interests. \n\nPeer review information: Nature Climate Change thanks Marie McGraw, Zhaoyi Shen and the other, anonymous, reviewer(s) for their contribution to the peer review of this work.\n\nIn the version of this Letter originally published, in Fig. 3 caption, the latitude zone for panels b and d was incorrect: \"0\u201350\u00b0 N (b and d)\" should have read \"20\u201350\u00b0 N (b and d)\". This error has now been corrected in the online versions of the Letter.\n\nSupplemental Material - 41558_2020_693_MOESM1_ESM.pdf
", "abstract": "Winter extreme weather events receive major public attention due to their serious impacts, but the dominant factors regulating their interdecadal trends have not been clearly established. Here, we show that the radiative forcing due to geospatially redistributed anthropogenic aerosols mainly determined the spatial variations of winter extreme weather in the Northern Hemisphere during 1970\u20132005, a unique transition period for global aerosol forcing. Over this period, the local Rossby wave activity and extreme events (top 10% in wave amplitude) exhibited marked declining trends at high latitudes, mainly in northern Eurasia. The combination of long-term observational data and a state-of-the-art climate model revealed the unambiguous signature of anthropogenic aerosols on the wintertime jet stream, planetary wave activity and surface temperature variability on interdecadal timescales. In particular, warming due to aerosol reductions in Europe enhanced the meridional temperature gradient on the jet's poleward flank and strengthened the zonal wind, resulting in significant suppression in extreme events over northern Eurasia. These results exemplify how aerosol forcing can impact large-scale extratropical atmospheric dynamics, and illustrate the importance of anthropogenic aerosols and their spatiotemporal variability in assessing the drivers of extreme weather in historical and future climate.", "date": "2020-03", "date_type": "published", "publication": "Nature Climate Change", "volume": "10", "number": "3", "publisher": "Nature Publishing Group", "pagerange": "225-230", "id_number": "CaltechAUTHORS:20191223-104532388", "issn": "1758-678X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20191223-104532388", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA/JPL/Caltech" }, { "agency": "NSF", "grant_number": "AGS-1700727" }, { "agency": "NSF", "grant_number": "AGS-1742178" } ] }, "local_group": { "items": [ { "id": "Astronomy-Department" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1038/s41558-020-0693-4", "primary_object": { "basename": "41558_2020_693_MOESM1_ESM.pdf", "url": "https://authors.library.caltech.edu/records/7vyx7-sv944/files/41558_2020_693_MOESM1_ESM.pdf" }, "resource_type": "article", "pub_year": "2020", "author_list": "Wang, Yuan; Le, Tianhao; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/mw4hr-71q29", "eprint_id": 100854, "eprint_status": "archive", "datestamp": "2023-08-22 04:02:28", "lastmod": "2023-10-19 22:10:53", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Su-Hui", "name": { "family": "Su", "given": "Hui" }, "orcid": "0000-0003-1265-9702" }, { "id": "Wu-Longtao", "name": { "family": "Wu", "given": "Longtao" }, "orcid": "0000-0001-8447-8180" }, { "id": "Zhai-Chengxing", "name": { "family": "Zhai", "given": "Chengxing" }, "orcid": "0000-0002-0291-4522" }, { "id": "Jiang-Jonathan-H", "name": { "family": "Jiang", "given": "Jonathan H." }, "orcid": "0000-0002-5929-8951" }, { "id": "Neelin-J-D", "name": { "family": "Neelin", "given": "J. David" }, "orcid": "0000-0001-9414-9962" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Observed Tightening of Tropical Ascent in Recent Decades and Linkage to Regional Precipitation Changes", "ispublished": "pub", "full_text_status": "public", "keywords": "Circulation; ITCZ; Precipitation; Ascent; Tightening; Drying", "note": "\u00a9 2020 American Geophysical Union. \n\nReceived 14 OCT 2019; Accepted 16 JAN 2020; Accepted article online 21 JAN 2020. \n\nThis work was performed at Jet Propulsion Laboratory, California Institute of Technology, under contract with NASA. This study is supported by NASA ACMAP\u2010AST and MAP projects. J. D. N. is supported by the NSF AGS\u20101540518 Grant. \n\nData Statement: The original reanalysis data sets, observations, and CMIP5 model simulations used in this study are all publicly available. The websites to download these data are as follows: \n\nERA\u2010I (http://apps.ecmwf.int/datasets/data/interim\u2010full\u2010moda/levtype=sfc/); MERRA\u20102 (https://gmao.gsfc.nasa.gov/reanalysis/MERRA\u20102/data_access/); JRA\u201055 (https://rda.ucar.edu/datasets/ds628.1/#description); GPCP precipitation (https://www.esrl.noaa.gov/psd/data/gridded/data.gpcp.html) OAFlux (http://oaflux.whoi.edu/data.html) NOAA OLR (https://www.esrl.noaa.gov/psd/data/gridded/data.interp_OLR.html); HadCRU4 Ts (http://www.metoffice.gov.uk/hadobs/hadcrut4); CMIP5 (http://cmip\u2010pcmdi.llnl.gov/cmip5/). The methods to process the data and generate the results are described in detail in the paper. Please contact the corresponding author at hui.su@jpl.nasa.gov for any questions.\n\nPublished - Su_et_al-2020-Geophysical_Research_Letters.pdf
Supplemental Material - grl60148-sup-0001-2019gl085809-si.docx
", "abstract": "Climate models predict that the tropical ascending region should tighten under global warming, but observational quantification of the tightening rate is limited. Here we show that the observed spatial extent of the relatively moist, rainy and cloudy regions in the tropics associated with large\u2010scale ascent has been decreasing at a rate of \u22121%/decade (\u22125%/K) from 1979 to 2016, resulting from combined effects of interdecadal variability and anthropogenic forcings, with the former contributing more than the latter. The tightening of tropical ascent is associated with an increase in the occurrence frequency of extremely strong ascent, leading to an increase in the average precipitation rate in the top 1% of monthly rainfall in the tropics. At the margins of the convective zones such as the Southeast Amazonia region, the contraction of large\u2010scale ascent is related to a long\u2010term drying trend about \u22123.2%/decade in the past 38 years.", "date": "2020-02-16", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "47", "number": "3", "publisher": "American Geophysical Union", "pagerange": "Art. No. e2019GL085809", "id_number": "CaltechAUTHORS:20200122-145021587", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200122-145021587", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA/JPL/Caltech" }, { "agency": "NSF", "grant_number": "AGS-1540518" } ] }, "local_group": { "items": [ { "id": "Astronomy-Department" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2019gl085809", "primary_object": { "basename": "grl60148-sup-0001-2019gl085809-si.docx", "url": "https://authors.library.caltech.edu/records/mw4hr-71q29/files/grl60148-sup-0001-2019gl085809-si.docx" }, "related_objects": [ { "basename": "Su_et_al-2020-Geophysical_Research_Letters.pdf", "url": "https://authors.library.caltech.edu/records/mw4hr-71q29/files/Su_et_al-2020-Geophysical_Research_Letters.pdf" } ], "resource_type": "article", "pub_year": "2020", "author_list": "Su, Hui; Wu, Longtao; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/yp6nf-q9996", "eprint_id": 100495, "eprint_status": "archive", "datestamp": "2023-08-19 19:44:41", "lastmod": "2023-10-18 20:35:23", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Kite-E-S", "name": { "family": "Kite", "given": "Edwin S." }, "orcid": "0000-0002-1426-1186" }, { "id": "Mischna-M-A", "name": { "family": "Mischna", "given": "Michael A." }, "orcid": "0000-0002-8022-5319" }, { "id": "Gao-Peter", "name": { "family": "Gao", "given": "Peter" }, "orcid": "0000-0002-8518-9601" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Turbet-M", "name": { "family": "Turbet", "given": "Martin" } } ] }, "title": "Methane release on Early Mars by atmospheric collapse and atmospheric reinflation", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2019 Published by Elsevier Ltd. \n\nReceived 30 August 2019, Revised 4 December 2019, Accepted 5 December 2019, Available online 2 January 2020. \n\nWe thank Jesse Tarnas, and an anonymous reviewer, for helpful reviews that led to an improved manuscript. We thank Alan Howard, Colin Goldblatt, Ross Irwin, Bob Craddock, Alejandro Soto, John Armstrong, Feng Tian, Itay Halevy, Alex Pavlov, Tom McCollom, Sarah Stewart, and Chris Oze for discussions, and Robin Wordsworth for sharing model output. The MATLAB scripts and GCM summary output used to make the figures in this paper may be obtained for unrestricted further use by contacting the lead author. This project has received funding from the European Union's Horizon 2020 research and innovation program under the Marie Sklodowska-Curie Grant Agreement No. 832738/ESCAPE. M.T. and E.S.K. acknowledge support from the France And Chicago Collaborating in The Sciences (FACCTS) program. E.S.K. acknowledges funding from NASA (NNX16AG55G). \n\nCRediT authorship contribution statement: Edwin S. Kite: Conceptualization, Formal analysis, Funding acquisition, Investigation, Methodology, Project administration, Software, Visualization, Writing - original draft, Writing - review & editing. Michael A. Mischna: Investigation, Methodology, Software, Writing - review & editing. Peter Gao: Investigation, Methodology. Yuk L. Yung: Software. Martin Turbet: Investigation. \n\nThe authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.\n\nSupplemental Material - 1-s2.0-S0032063319302703-mmc1.xml
", "abstract": "A candidate explanation for Early Mars rivers is atmospheric warming due to surface release of H\u2082 or CH\u2084 gas. However, it remains unknown how much gas could be released in a single event. We model the CH\u2084 release by one mechanism for rapid release of CH\u2084 from clathrate. By modeling how CH\u2084-clathrate release is affected by changes in Mars' obliquity and atmospheric composition, we find that a large fraction of total outgassing from CH\u2084 clathrate occurs following Mars' first prolonged atmospheric collapse. This atmosphere-collapse-initiated CH\u2084-release mechanism has three stages. (1) Rapid collapse of Early Mars' carbon dioxide atmosphere initiates a slower shift of water ice from high ground to the poles. (2) Upon subsequent CO\u2082-atmosphere re-inflation and CO\u2082-greenhouse warming, low-latitude clathrate decomposes and releases methane gas. (3) Methane can then perturb atmospheric chemistry and surface temperature, until photochemical processes destroy the methane.\nWithin our model, we find that under some circumstances a Titan-like haze layer would be expected to form, consistent with transient deposition of abundant complex abiotic organic matter on the Early Mars surface. We also find that this CH\u2084-release mechanism can warm Early Mars, but special circumstances are required in order to uncork 10\u00b9\u2077\u202fkg of CH\u2084, the minimum needed for strong warming. Specifically, strong warming only occurs when the fraction of the hydrate stability zone that is initially occupied by clathrate exceeds 10%, and when Mars' first prolonged atmospheric collapse occurs for atmospheric pressure >1\u202fbar.", "date": "2020-02", "date_type": "published", "publication": "Planetary and Space Science", "volume": "181", "publisher": "Elsevier", "pagerange": "Art. No. 104820", "id_number": "CaltechAUTHORS:20200103-102636749", "issn": "0032-0633", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200103-102636749", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Marie Curie Fellowship", "grant_number": "832738" }, { "agency": "France And Chicago Collaborating in The Sciences (FACCTS)" }, { "agency": "NASA", "grant_number": "NNX16AG55G" } ] }, "local_group": { "items": [ { "id": "Astronomy-Department" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/j.pss.2019.104820", "primary_object": { "basename": "1-s2.0-S0032063319302703-mmc1.xml", "url": "https://authors.library.caltech.edu/records/yp6nf-q9996/files/1-s2.0-S0032063319302703-mmc1.xml" }, "resource_type": "article", "pub_year": "2020", "author_list": "Kite, Edwin S.; Mischna, Michael A.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/h926h-q7848", "eprint_id": 99269, "eprint_status": "archive", "datestamp": "2023-08-22 03:38:13", "lastmod": "2023-10-18 18:11:30", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Vi\u00fadez-Moreiras-D", "name": { "family": "Vi\u00fadez-Moreiras", "given": "D." } }, { "id": "Saiz-Lopez-A", "name": { "family": "Saiz-Lopez", "given": "A." } }, { "id": "Blaszczak-Boxe-C-S", "name": { "family": "Blaszczak-Boxe", "given": "C. S." }, "orcid": "0000-0002-5288-961X" }, { "id": "Rodriguez-Manfredi-J-A", "name": { "family": "Rodriguez Manfredi", "given": "J. A." }, "orcid": "0000-0003-0461-9815" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Y. L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Diurnal Variation in Mars Equatorial Odd Oxygen Species: Chemical Production and Loss Mechanisms", "ispublished": "pub", "full_text_status": "public", "keywords": "Ozone distribution; Photochemistry; Martian atmosphere modeling; Atmospheric characterization; NASA Mars Science Laboratory (MSL)", "note": "\u00a9 2019 The Authors. Published by Elsevier Inc. This is an open access article under the CC BY-NC-ND license. \n\nReceived 26 April 2019, Revised 23 September 2019, Accept ed 30 September 2019, Available online 15 October 2019. \n\nThis research has been su pported by the Spanish Ministry of Economy and Competiveness(MINECO), under projects ESP2014-54256-C4-1-R and ESP2016-79612-C3-1-R. The authors thank Michael D. Smith and an anonymous reviewer, whose comments helped improve this paper. \n\nThe authors declare no conflict of interest.\n\nPublished - 1-s2.0-S0019103519303021-main.pdf
Supplemental Material - 1-s2.0-S0019103519303021-mmc1.xml
Supplemental Material - 1-s2.0-S0019103519303021-mmc2.pdf
Supplemental Material - 1-s2.0-S0019103519303021-mmc3.docx
", "abstract": "Odd oxygen (O, O(\u00b9D), O\u2083) abundance and its variability in the Martian atmosphere results from complex physical and chemical interactions among atmospheric species, which are driven mainly by solar radiation and atmospheric conditions. Although our knowledge of Mars' ozone distribution and variability has been significantly improved with the arrival of several recent orbiters, the data acquired by such missions is not enough to properly characterize its diurnal variation. Thus, photochemical models are useful tools to assist in such a characterization. Here, both the Martian ozone vertical distribution and its diurnal variation for equatorial latitudes are studied, using the JPL/Caltech one-dimensional photochemical model and diurnally-variable atmospheric profiles. The chosen equatorial latitude-region is based on the recent and future plans of NASA and other agencies to study this region by different surface missions. A production and loss analysis is performed in order to characterize the chemical mechanisms that drive odd oxygen's diurnal budget and variability on Mars making use of the comprehensive chemistry implemented in the model. The diurnal variation shows large differences in the abundance between daytime and nighttime; and variable behavior depending on the atmospheric layer. The photolysis-driven ozone diurnal profile is obtained at the surface, whilst a sharp decrease is obtained in the upper troposphere at daytime, which originates from the large differences in atomic oxygen abundances between atmospheric layers. Finally, no clear anticorrelation between ozone and water vapor is found in the diurnal cycle, contrary to the strong correlation observed by orbiters on a seasonal timescale.", "date": "2020-01-15", "date_type": "published", "publication": "Icarus", "volume": "336", "publisher": "Elsevier", "pagerange": "Art. No. 113458", "id_number": "CaltechAUTHORS:20191015-100957612", "issn": "0019-1035", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20191015-100957612", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Ministerio de Econom\u00eda, Industria y Competitividad (MINECO)", "grant_number": "ESP2014-54256-C4-1-R" }, { "agency": "Ministerio de Econom\u00eda, Industria y Competitividad (MINECO)", "grant_number": "ESP2016-79612-C3-1-R" } ] }, "local_group": { "items": [ { "id": "Astronomy-Department" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/j.icarus.2019.113458", "primary_object": { "basename": "1-s2.0-S0019103519303021-main.pdf", "url": "https://authors.library.caltech.edu/records/h926h-q7848/files/1-s2.0-S0019103519303021-main.pdf" }, "related_objects": [ { "basename": "1-s2.0-S0019103519303021-mmc1.xml", "url": "https://authors.library.caltech.edu/records/h926h-q7848/files/1-s2.0-S0019103519303021-mmc1.xml" }, { "basename": "1-s2.0-S0019103519303021-mmc2.pdf", "url": "https://authors.library.caltech.edu/records/h926h-q7848/files/1-s2.0-S0019103519303021-mmc2.pdf" }, { "basename": "1-s2.0-S0019103519303021-mmc3.docx", "url": "https://authors.library.caltech.edu/records/h926h-q7848/files/1-s2.0-S0019103519303021-mmc3.docx" } ], "resource_type": "article", "pub_year": "2020", "author_list": "Vi\u00fadez-Moreiras, D.; Saiz-Lopez, A.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/ywc9x-mjr87", "eprint_id": 99661, "eprint_status": "archive", "datestamp": "2023-08-22 03:27:13", "lastmod": "2023-10-18 18:38:21", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Zeng-Zhao-Cheng", "name": { "family": "Zeng", "given": "Zhao-Cheng" }, "orcid": "0000-0002-0008-6508" }, { "id": "Chen-Sihe", "name": { "family": "Chen", "given": "Sihe" } }, { "id": "Natraj-V", "name": { "family": "Natraj", "given": "Vijay" }, "orcid": "0000-0003-3154-9429" }, { "id": "Le-Tianhao", "name": { "family": "Le", "given": "Tianhao" } }, { "id": "Xu-Feng", "name": { "family": "Xu", "given": "Feng" }, "orcid": "0000-0001-5155-9478" }, { "id": "Merrelli-A", "name": { "family": "Merrelli", "given": "Aronne" } }, { "id": "Crisp-D", "name": { "family": "Crisp", "given": "David" }, "orcid": "0000-0002-4573-9998" }, { "id": "Sander-S-P", "name": { "family": "Sander", "given": "Stanley P." }, "orcid": "0000-0003-1424-3620" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Constraining the vertical distribution of coastal dust aerosol using OCO-2 O\u2082 A-band measurements", "ispublished": "pub", "full_text_status": "public", "keywords": "Aerosol profiling; OCO-2; O2 A-band; CALIPSO; Dust", "note": "\u00a9 2019 Elsevier Inc. \n\nReceived 12 August 2019, Revised 19 October 2019, Accepted 23 October 2019, Available online 5 November 2019. \n\nWe thank Run-Lie Shia at Caltech, Suniti Sanghavi at JPL, and Chao Liu at NUIST for stimulating discussions. The OCO-2 Forward model is available at https://github.com/nasa/RtRetrievalFramework. The L1bSc OCO-2 radiances are available online from the NASA Goddard GES DISC at https://disc. gsfc.nasa.gov/datacollection/OCO2_ L1B_Science_7.html. MERRAero monthly 3-h averaged dust column density data can be downloaded from (https://portal.nccs.nasa.gov/cgi-lats4d/webform.cgi?&i=GEOS-5/MERRAero/monthly/tavg3hr_2d_aer_Nx). S. C. acknowledges support from the SURF program at the California Institute of Technology and from the National University of Singapore. V. N. acknowledges support from the NASA Earth Science US Participating Investigator program (solicitation NNH16ZDA001N-ESUSPI). F. X. acknowledges support from the NASA Remote Sensing Theory program under grant 14-RST14-0100. A. M. acknowledges support from NASA grant award 80NSSC18K0891 as part of the NASA Science Team for the OCO missions. Z. C. Zeng would like to dedicate this paper to his newborn daughter Judy Zeng. We thank the support from the Jet Propulsion Laboratory Research and Technology Development Program. We also thank the three reviewers for their constructive comments and suggestions. \n\nDeclaration of competing interest: None.\n\nSubmitted - 1908.05769.pdf
", "abstract": "Quantifying the vertical distribution of atmospheric aerosols is crucial for estimating their impact on the Earth's energy budget and climate, improving forecast of air pollution in cities, and reducing biases in the retrieval of greenhouse gases (GHGs) from space. However, to date, passive remote sensing measurements have provided limited information about aerosol extinction profiles. In this study, we propose the use of a spectral sorting approach to constrain the aerosol vertical structure using spectra of reflected sunlight absorption within the molecular oxygen (O\u2082) A-band collected by the Orbiting Carbon Observatory-2 (OCO-2). The effectiveness of the approach is evaluated using spectra acquired over the western Sahara coast by comparing the aerosol profile retrievals with lidar measurements from the Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP). Using a radiative transfer model to simulate OCO-2 measurements, we found that high-resolution O\u2082 A-band measurements have high sensitivity to aerosol optical depth (AOD) and aerosol layer height (ALH). Retrieved estimates of AOD and ALH based on a look up table technique show good agreement with CALIPSO measurements, with correlation coefficients of 0.65 and 0.53, respectively. The strength of the proposed spectral sorting technique lies in its ability to identify spectral channels with high sensitivity to AOD and ALH and extract the associated information from the observed radiance in a straightforward manner. The proposed approach has the potential to enable future passive remote sensing missions to map the aerosol vertical distribution on a global scale.", "date": "2020-01", "date_type": "published", "publication": "Remote Sensing of Environment", "volume": "236", "publisher": "Elsevier", "pagerange": "Art. No. 111494", "id_number": "CaltechAUTHORS:20191105-084121561", "issn": "0034-4257", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20191105-084121561", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Caltech Summer Undergraduate Research Fellowship (SURF)" }, { "agency": "National University of Singapore" }, { "agency": "NASA", "grant_number": "NNH16ZDA001N-ESUSPI" }, { "agency": "NASA", "grant_number": "14-RST14-0100" }, { "agency": "NASA", "grant_number": "80NSSC18K0891" }, { "agency": "JPL Research and Technology Development Fund" } ] }, "local_group": { "items": [ { "id": "Astronomy-Department" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/j.rse.2019.111494", "primary_object": { "basename": "1908.05769.pdf", "url": "https://authors.library.caltech.edu/records/ywc9x-mjr87/files/1908.05769.pdf" }, "resource_type": "article", "pub_year": "2020", "author_list": "Zeng, Zhao-Cheng; Chen, Sihe; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/mrr4t-ywy77", "eprint_id": 100002, "eprint_status": "archive", "datestamp": "2023-08-19 19:21:59", "lastmod": "2023-10-18 18:59:16", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Beichman-C-A", "name": { "family": "Beichman", "given": "Charles" }, "orcid": "0000-0002-5627-5471" }, { "id": "Ygouf-M", "name": { "family": "Ygouf", "given": "Marie" }, "orcid": "0000-0001-7591-2731" }, { "id": "Llop-Sayson-J-D", "name": { "family": "Llop Sayson", "given": "Jorge" } }, { "id": "Mawet-D", "name": { "family": "Mawet", "given": "Dimitri" }, "orcid": "0000-0002-8895-4735" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk" }, "orcid": "0000-0002-4263-2562" }, { "id": "Choquet-\u00c9lodie", "name": { "family": "Choquet", "given": "\u00c9lodie" }, "orcid": "0000-0002-9173-0740" }, { "id": "Kervella-P", "name": { "family": "Kervella", "given": "Pierre" }, "orcid": "0000-0003-0626-1749" }, { "id": "Boccaletti-A", "name": { "family": "Boccaletti", "given": "Anthony" }, "orcid": "0000-0001-9353-2724" }, { "id": "Belikov-R", "name": { "family": "Belikov", "given": "Ruslan" } }, { "id": "Lissauer-J-J", "name": { "family": "Lissauer", "given": "Jack J." }, "orcid": "0000-0001-6513-1659" }, { "id": "Quarles-B", "name": { "family": "Quarles", "given": "Billy" } }, { "id": "Lagage-P-O", "name": { "family": "Lagage", "given": "Pierre-Olivier" } }, { "id": "Dicken-D", "name": { "family": "Dicken", "given": "Daniel" } }, { "id": "Hu-Renyu", "name": { "family": "Hu", "given": "Renyu" }, "orcid": "0000-0003-2215-8485" }, { "id": "Mennesson-B", "name": { "family": "Mennesson", "given": "Bertrand" }, "orcid": "0000-0003-4205-4800" }, { "id": "Ressler-M-E", "name": { "family": "Ressler", "given": "Mike" } }, { "id": "Serabyn-E", "name": { "family": "Serabyn", "given": "Eugene" } }, { "id": "Krist-John-E", "name": { "family": "Krist", "given": "John" } }, { "id": "Bendek-E-A", "name": { "family": "Bendek", "given": "Eduardo" } }, { "id": "Leisenring-J", "name": { "family": "Leisenring", "given": "Jarron" }, "orcid": "0000-0002-0834-6140" }, { "id": "Pueyo-L", "name": { "family": "Pueyo", "given": "Laurent" }, "orcid": "0000-0003-3818-408X" } ] }, "title": "Searching for Planets Orbiting \u03b1 Cen A with the James Webb Space Telescope", "ispublished": "pub", "full_text_status": "public", "keywords": "infrared: planetary systems \u2013 planetary systems \u2013 planets and satellites: detection \u2013 space vehicles: instruments", "note": "\u00a9 2019. The Astronomical Society of the Pacific. \n\nReceived 2019 August 25; accepted 2019 October 14; published 2019 December 12. \n\nSome of the research described in this publication was carried out in part at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration. Copyright 2019 California Inst of Technology. All rights reserved.\n\nPublished - Beichman_2020_PASP_132_015002.pdf
Accepted Version - 1910.09709.pdf
", "abstract": "\u03b1 Centauri A is the closest solar-type star to the Sun and offers an excellent opportunity to detect the thermal emission of a mature planet heated by its host star. The MIRI coronagraph on JWST can search the 1-3 AU (1\"-2\") region around \u03b1 Cen A which is predicted to be stable within the \u03b1 Cen AB system. We demonstrate that with reasonable performance of the telescope and instrument, a 20 hr program combining on-target and reference star observations at 15.5 um could detect thermal emission from planets as small as ~5 R\u2295. Multiple visits every 3-6 months would increase the geometrical completeness, provide astrometric confirmation of detected sources, and push the radius limit down to ~3 R\u2295. An exozodiacal cloud only a few times brighter than our own should also be detectable, although a sufficiently bright cloud might obscure any planet present in the system. While current precision radial velocity (PRV) observations set a limit of 50-100 M\u2295 at 1-3 AU for planets orbiting \u03b1 Cen A, there is a broad range of exoplanet radii up to 10 RE consistent with these mass limits. A carefully planned observing sequence along with state-of-the-art post-processing analysis could reject the light from \u03b1 Cen A at the level of ~10\u207b\u2075 at 1\"-2\" and minimize the influence of \u03b1 Cen B located 7-8\" away in the 2022-2023 timeframe. These space-based observations would complement on-going imaging experiments at shorter wavelengths as well as PRV and astrometric experiments to detect planets dynamically. Planetary demographics suggest that the likelihood of directly imaging a planet whose mass and orbit are consistent with present PRV limits is small, ~5%, and possibly lower if the presence of a binary companion further reduces occurrence rates. However, at a distance of just 1.34 pc, \u03b1 Cen A is our closest sibling star and certainly merits close scrutiny.", "date": "2020-01", "date_type": "published", "publication": "Publications of the Astronomical Society of the Pacific", "volume": "132", "number": "1007", "publisher": "Astronomical Society of the Pacific", "pagerange": "Art. No. 015002", "id_number": "CaltechAUTHORS:20191121-152416477", "issn": "0004-6280", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20191121-152416477", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA/JPL/Caltech" } ] }, "local_group": { "items": [ { "id": "Infrared-Processing-and-Analysis-Center-(IPAC)" }, { "id": "Astronomy-Department" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1088/1538-3873/ab5066", "primary_object": { "basename": "1910.09709.pdf", "url": "https://authors.library.caltech.edu/records/mrr4t-ywy77/files/1910.09709.pdf" }, "related_objects": [ { "basename": "Beichman_2020_PASP_132_015002.pdf", "url": "https://authors.library.caltech.edu/records/mrr4t-ywy77/files/Beichman_2020_PASP_132_015002.pdf" } ], "resource_type": "article", "pub_year": "2020", "author_list": "Beichman, Charles; Ygouf, Marie; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/n46n7-5jt46", "eprint_id": 100327, "eprint_status": "archive", "datestamp": "2023-08-19 14:51:46", "lastmod": "2024-02-02 21:05:13", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Hu-Renyu", "name": { "family": "Hu", "given": "Renyu" }, "orcid": "0000-0003-2215-8485" }, { "id": "Beichman-C-A", "name": { "family": "Beichman", "given": "Charles A." }, "orcid": "0000-0002-5627-5471" }, { "name": { "family": "Brain", "given": "David" } }, { "name": { "family": "Chen", "given": "Pin" } }, { "name": { "family": "Damiano", "given": "Mario" } }, { "name": { "family": "Dawson", "given": "Rebekah" }, "orcid": "0000-0001-9677-1296" }, { "name": { "family": "Friedson", "given": "A. James" } }, { "name": { "family": "Hasagawa", "given": "Yasuhiro" } }, { "id": "Howard-A-W", "name": { "family": "Howard", "given": "Andrew" }, "orcid": "0000-0001-8638-0320" }, { "name": { "family": "Johnson", "given": "Robert" } }, { "name": { "family": "Kataria", "given": "Tiffany" }, "orcid": "0000-0003-3759-9080" }, { "name": { "family": "Kidd", "given": "Richard" } }, { "name": { "family": "Kite", "given": "Edwin" }, "orcid": "0000-0002-1426-1186" }, { "id": "Knutson-H-A", "name": { "family": "Knutson", "given": "Heather" }, "orcid": "0000-0002-5375-4725" }, { "name": { "family": "Lyra", "given": "Wladimir" }, "orcid": "0000-0002-3768-7542" }, { "name": { "family": "Mischna", "given": "Michael" }, "orcid": "0000-0002-8022-5319" }, { "name": { "family": "Planavsky", "given": "Noah" } }, { "name": { "family": "Reinhard", "given": "Chris" } }, { "name": { "family": "Schlichting", "given": "Hilke" } }, { "name": { "family": "Seager", "given": "Sara" }, "orcid": "0000-0002-6892-6948" }, { "name": { "family": "Sotin", "given": "Christophe" } }, { "name": { "family": "Swain", "given": "Mark" } }, { "name": { "family": "Turner", "given": "Neal" } }, { "name": { "family": "West", "given": "Robert" } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk" }, "orcid": "0000-0002-4263-2562" }, { "name": { "family": "Zellem", "given": "Robert" }, "orcid": "0000-0001-7547-0398" } ] }, "title": "The Super-Earth Opportunity - Search for Habitable Exoplanets in the 2020s", "ispublished": "unpub", "full_text_status": "public", "note": "The research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration.\n\nSubmitted - 1903.05258.pdf
", "abstract": "The recent discovery of a staggering diversity of planets beyond the Solar System has brought with it a greatly expanded search space for habitable worlds. The Kepler exoplanet survey has revealed that most planets in our interstellar neighborhood are larger than Earth and smaller than Neptune. Collectively termed super-Earths and mini-Neptunes, some of these planets may have the conditions to support liquid water oceans, and thus Earth-like biology, despite differing in many ways from our own planet. In addition to their quantitative abundance, super-Earths are relatively large and are thus more easily detected than true Earth twins. As a result, super-Earths represent a uniquely powerful opportunity to discover and explore a panoply of fascinating and potentially habitable planets in 2020 - 2030 and beyond.", "date": "2019-12-17", "date_type": "published", "publisher": "arXiv", "id_number": "CaltechAUTHORS:20191217-104655016", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20191217-104655016", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA/JPL/Caltech" } ] }, "local_group": { "items": [ { "id": "Infrared-Processing-and-Analysis-Center-(IPAC)" }, { "id": "Astronomy-Department" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.48550/arXiv.1903.05258", "primary_object": { "basename": "1903.05258.pdf", "url": "https://authors.library.caltech.edu/records/n46n7-5jt46/files/1903.05258.pdf" }, "resource_type": "monograph", "pub_year": "2019", "author_list": "Hu, Renyu; Beichman, Charles A.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/4ch82-9b183", "eprint_id": 98277, "eprint_status": "archive", "datestamp": "2023-08-22 02:25:13", "lastmod": "2023-10-18 17:12:50", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Fan-Siteng", "name": { "family": "Fan", "given": "Siteng" }, "orcid": "0000-0002-3041-4680" }, { "id": "Li-Cheng-CIT-Planetary Sciences", "name": { "family": "Li", "given": "Cheng" }, "orcid": "0000-0002-8280-3119" }, { "id": "Li-Jia-Zheng", "name": { "family": "Li", "given": "Jia-Zheng" } }, { "id": "Bartlett-S", "name": { "family": "Bartlett", "given": "Stuart" }, "orcid": "0000-0001-5680-476X" }, { "id": "Jiang-Jonathan-H", "name": { "family": "Jiang", "given": "Jonathan H." }, "orcid": "0000-0002-5929-8951" }, { "id": "Natraj-V", "name": { "family": "Natraj", "given": "Vijay" }, "orcid": "0000-0003-3154-9429" }, { "id": "Crisp-D", "name": { "family": "Crisp", "given": "David" }, "orcid": "0000-0002-4573-9998" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Earth as an Exoplanet: A Two-dimensional Alien Map", "ispublished": "pub", "full_text_status": "public", "keywords": "Exoplanet astronomy; Exoplanet atmospheres; Exoplanet atmospheric variability; Exoplanet detection methods; Exoplanet surface characteristics; Exoplanet surface composition; Exoplanet surface variability; Exoplanets; Extrasolar rocky planets", "note": "\u00a9 2019 The American Astronomical Society. \n\nReceived 2019 July 1; revised 2019 August 5; accepted 2019 August 12; published 2019 August 27. \n\nThis work was partly supported by the Jet Propulsion Laboratory, California Institute of Technology, under contract with NASA. Y.L.Y. and D.C. acknowledge support by the Virtual Planetary Laboratory at the University of Washington. We thank Lixiang Gu and Mimi Gerstell for proofreading the manuscript.\n\nPublished - Fan_2019_ApJL_882_L1.pdf
Accepted Version - 1908.04350.pdf
", "abstract": "Resolving spatially varying exoplanet features from single-point light curves is essential for determining whether Earth-like worlds harbor geological features and/or climate systems that influence habitability. To evaluate the feasibility and requirements of this spatial-feature resolving problem, we present an analysis of multi-wavelength single-point light curves of Earth, where it plays the role of a proxy exoplanet. Here, ~10,000 Deep Space Climate Observatory/Earth Polychromatic Imaging Camera frames collected over a two-year period were integrated over the Earth's disk to yield a spectrally dependent point source and analyzed using singular value decomposition. We found that, between the two dominant principal components (PCs), the second PC contains surface-related features of the planet, while the first PC mainly includes cloud information. We present the first two-dimensional (2D) surface map of Earth reconstructed from light curve observations without any assumptions of its spectral properties. This study serves as a baseline for reconstructing the surface features of Earth-like exoplanets in the future.", "date": "2019-09-01", "date_type": "published", "publication": "Astrophysical Journal Letters", "volume": "882", "number": "1", "publisher": "American Astronomical Society", "pagerange": "Art. No. L1", "id_number": "CaltechAUTHORS:20190828-074526085", "issn": "2041-8213", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190828-074526085", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA/JPL/Caltech" }, { "agency": "University of Washington" } ] }, "local_group": { "items": [ { "id": "Astronomy-Department" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.3847/2041-8213/ab3a49", "primary_object": { "basename": "1908.04350.pdf", "url": "https://authors.library.caltech.edu/records/4ch82-9b183/files/1908.04350.pdf" }, "related_objects": [ { "basename": "Fan_2019_ApJL_882_L1.pdf", "url": "https://authors.library.caltech.edu/records/4ch82-9b183/files/Fan_2019_ApJL_882_L1.pdf" } ], "resource_type": "article", "pub_year": "2019", "author_list": "Fan, Siteng; Li, Cheng; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/a9fmp-wmm50", "eprint_id": 98591, "eprint_status": "archive", "datestamp": "2023-08-19 17:15:10", "lastmod": "2023-10-18 17:29:23", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Bartlett-S-J", "name": { "family": "Bartlett", "given": "S. J." }, "orcid": "0000-0001-5680-476X" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Y. L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Boolean logic by convective obstacle flows", "ispublished": "pub", "full_text_status": "restricted", "keywords": "convection, computation, Boolean logic", "note": "\u00a9 2019 The Author(s). Published by the Royal Society. \n\nManuscript received 28/03/2019; Manuscript accepted 16/07/2019; Published online 14/08/2019; Published in print 08/2019. \n\nData accessibility: The simulation code for generating all results can be found in the electronic supplementary material. \n\nAuthors' contributions: S.J.B. first noticed that convective systems might have computational abilities, he wrote the code for the simulations, analysed the results and wrote the paper. Y.L.Y. provided guidance and advice. \n\nWe declare we have no competing interests. \n\nThis work was supported by the Caltech Division of Geological and Planetary Sciences Discovery Fund. Y.L.Y. was supported in part by an NAI Virtual Planetary Laboratory grant from the University of Washington to the Jet Propulsion Laboratory and California Institute of Technology.", "abstract": "We present a potential new mode of natural computing in which simple, heat-driven fluid flows perform Boolean logic operations. The system comprises a two-dimensional single-phase fluid that is heated from below and cooled from above, with two obstacles placed on the horizontal mid-plane. The obstacles remove all vertical momentum that flows into them. The horizontal momentum extraction of the obstacles is controlled in a binary fashion, and constitutes the 2-bit input. The output of the system is a thresholded measure of the energy extracted by the obstacles. Due to the existence of multiple attractors in the phase space of this system, the input\u2013output relationships are equivalent to those of the OR, XOR or NAND gates, depending on the threshold and obstacle separation. The ability to reproduce these logical operations suggests that convective flows might have the potential to perform more general computations, despite the fact that they do not involve electronics, chemistry or multiple fluid phases.", "date": "2019-08-07", "date_type": "published", "publication": "Proceedings of the Royal Society A: Mathematical, physical, and engineering sciences", "volume": "475", "number": "2228", "publisher": "Royal Society of London", "pagerange": "Art. No. 20190192", "id_number": "CaltechAUTHORS:20190911-154806058", "issn": "1364-5021", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190911-154806058", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Caltech Division of Geological and Planetary Sciences" }, { "agency": "University of Washington" } ] }, "local_group": { "items": [ { "id": "Astronomy-Department" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1098/rspa.2019.0192", "resource_type": "article", "pub_year": "2019", "author_list": "Bartlett, S. J. and Yung, Y. L." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/4njb3-ady18", "eprint_id": 95310, "eprint_status": "archive", "datestamp": "2023-08-22 02:07:51", "lastmod": "2023-10-20 19:06:38", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Zhao-Bin", "name": { "family": "Zhao", "given": "Bin" }, "orcid": "0000-0001-8438-9188" }, { "id": "Wang-Yuan", "name": { "family": "Wang", "given": "Yuan" }, "orcid": "0000-0001-6657-8401" }, { "id": "Gu-Yu", "name": { "family": "Gu", "given": "Yu" }, "orcid": "0000-0002-3412-0794" }, { "id": "Liou-Kuo-Nan", "name": { "family": "Liou", "given": "Kuo-Nan" } }, { "id": "Jiang-Jonathan-H", "name": { "family": "Jiang", "given": "Jonathan H." }, "orcid": "0000-0002-5929-8951" }, { "id": "Fan-Jiwen", "name": { "family": "Fan", "given": "Jiwen" }, "orcid": "0000-0001-5280-4391" }, { "id": "Liu-Xiaohong", "name": { "family": "Liu", "given": "Xiaohong" }, "orcid": "0000-0002-3994-5955" }, { "id": "Huang-Lei", "name": { "family": "Huang", "given": "Lei" }, "orcid": "0000-0002-4941-7814" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Ice nucleation by aerosols from anthropogenic pollution", "ispublished": "pub", "full_text_status": "public", "keywords": "Atmospheric science; Environmental sciences", "note": "\u00a9 2019 Springer Nature Publishing AG. \n\nReceived 16 December 2018; Accepted 15 May 2019; Published\n01 July 2019. \n\nData availability: The satellite and meteorology data products used in this study are publicly available at the following sites: \n\nMODIS/Aqua MYD04 and MYD06 products: https://earthdata.nasa.gov/ \n\nCALIOP/CALIPSO 05kmMLay and 05kmAPro products: https://eosweb.larc.nasa.gov/ \n\nAIRS/Aqua AIRIBRAD product: https://disc.gsfc.nasa.gov/ \n\nNCEP Final Analysis product: https://rda.ucar.edu/datasets/ds083.2/ \n\nOther data supporting the findings of this study are available within the Article and Supplementary Information. \n\nCode availability: The code of the WRF-SBM model is available at http://www2.mmm.ucar.edu/wrf/users/download/get_source.html. The scripts used to process the satellite data can be requested from the corresponding authors. \n\nThis study is supported by the NASA ROSES TASNPP (80NSSC18K0985) and NSF AGS-1701526, AGS-1700727 and AGS-1642289 grants. We acknowledge the support of the Jet Propulsion Laboratory, California Institute of Technology, under contract with NASA, and the Joint Institute for Regional Earth System Science and Engineering at the University of California Los Angeles. The effort of J.F. was supported by the US Department of Energy (DOE) Early Career Research Program. X.L. was supported by the US DOE Atmospheric System Research Program (grants DE-SC0014239 and DE-SC0018926). We would like to acknowledge high-performance computing support from Cheyenne (https://doi.org/10.5065/D6RX99HX) provided by NCAR's Computational and Information Systems Laboratory, sponsored by the National Science Foundation. \n\nAuthor Contributions: B.Z., Y.G. and Y.W. designed the research; B.Z., Y.G., Y.W. and L.H. performed the satellite data analysis; Y.W., B.Z. and J.F. performed the model simulation; B.Z., Y.W., Y.G., K.-N.L., J.F., J.H.J. and X.L. analysed the results; B.Z., Y.W., Y.G., K.-N.L., J.H.J., J.F., X.L. and Y.L.Y. wrote the paper. \n\nThe authors declare no competing interests.\n\nSupplemental Material - 41561_2019_389_MOESM1_ESM.pdf
", "abstract": "The formation of ice particles in the atmosphere strongly affects cloud properties and the climate. While mineral dust is known to be an effective ice nucleating particle, the role of aerosols from anthropogenic pollution in ice nucleation is still under debate. Here we probe the ice nucleation ability of different aerosol types by combining 11-year observations from multiple satellites and cloud-resolving model simulations. We find that, for strong convective systems, the ice particle effective radius near cloud top decreases with increasing loading of polluted continental aerosols, because the ice formation is dominated by homogeneous freezing of cloud droplets, which are smaller under more polluted conditions. By contrast, an increase in ice particle effective radius with polluted continental aerosols is found for moderate convection. Our model simulations suggest that this positive correlation is explained by enhanced heterogeneous ice nucleation and prolonged ice particle growth at higher aerosol loading, indicating that polluted continental aerosols contain a considerable fraction of ice nucleating particles. Similar aerosol\u2013ice relationships are observed for dust aerosols, further corroborating the ice nucleation ability of polluted continental aerosols. By catalysing ice formation, aerosols from anthropogenic pollution could have profound impacts on cloud lifetime and radiative effect as well as precipitation efficiency.", "date": "2019-08", "date_type": "published", "publication": "Nature Geoscience", "volume": "12", "number": "8", "publisher": "Nature Publishing Group", "pagerange": "602-607", "id_number": "CaltechAUTHORS:20190507-141107713", "issn": "1752-0894", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190507-141107713", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "80NSSC18K0985" }, { "agency": "NSF", "grant_number": "AGS-1701526" }, { "agency": "NSF", "grant_number": "AGS-1700727" }, { "agency": "NSF", "grant_number": "AGS-1642289" }, { "agency": "NASA/JPL/Caltech" }, { "agency": "UCLA" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0014239" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0018926" } ] }, "local_group": { "items": [ { "id": "Astronomy-Department" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1038/s41561-019-0389-4", "primary_object": { "basename": "41561_2019_389_MOESM1_ESM.pdf", "url": "https://authors.library.caltech.edu/records/4njb3-ady18/files/41561_2019_389_MOESM1_ESM.pdf" }, "resource_type": "article", "pub_year": "2019", "author_list": "Zhao, Bin; Wang, Yuan; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/1dn56-p6v27", "eprint_id": 97636, "eprint_status": "archive", "datestamp": "2023-08-22 02:10:29", "lastmod": "2023-10-18 16:10:05", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Li-Andy-X", "name": { "family": "Li", "given": "Andy X." }, "orcid": "0000-0002-3240-3483" }, { "id": "Wang-Yuan", "name": { "family": "Wang", "given": "Yuan" }, "orcid": "0000-0001-6657-8401" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Inducing Factors and Impacts of the October 2017 California Wildfires", "ispublished": "pub", "full_text_status": "public", "keywords": "Wildfire; Carbon Dioxide; Drought", "note": "\u00a9 2019 The Authors. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited. \n\nReceived 6 APR 2019; Accepted 30 JUL 2019; Accepted article online 4 AUG 2019; Published online 27 AUG 2019. \n\nWe thank two anonymous referees and editor for their time and constructive suggestions. We thank helpful comments from Sally Newman and William Chan. Y. Y. is supported by the NASA OCO\u20102 project. Y. W. acknowledges the support from AQ\u2010SRTD at Jet Propulsion Laboratory and Multi\u2010Angle Imager for Aerosols project. ECMWF\u2010Interim data can be downloaded at https://apps.ecmwf.int/datasets/data/interim\u2010full\u2010daily/levtype=sfc/ website. GPCP precipitation data can be downloaded at https://www.esrl.noaa.gov/psd/data/gridded/data.gpcp website. OCO\u20102 X_(CO2) retrievals can be downloaded at https://oco.jpl.nasa.gov/science/OCO2DataCenter/ website. MODIS burned area data can be downloaded at ftp://fuoco.geog.umd.edu/MCD64CMQ/C6/ website.\n\nPublished - Li_et_al-2019-Earth_and_Space_Science.pdf
Supplemental Material - ess2358-sup-0001-2019ea000661-si.docx
", "abstract": "The California wildfires of October 2017 were one of the largest wildfires in the state's history. Using surface temperature, surface pressure, cloud liquid and ice water contents, precipitation data, and wind data, we explore possible reasons for the wildfires. It is found that the mean surface temperature in California has increased, while mean cloud water contents and mean precipitation in California has decreased over the past 39 years. Higher temperatures, higher surface pressures, lower cloud water contents, lower precipitation, enhanced surface Santa Ana winds, and enhanced sinking air have set up favorable meteorological conditions for stronger wildfires in California, such as the October 2017 wildfires. Furthermore, the CO_2 data from the Orbiting Carbon Observatory 2 (OCO\u20102) satellite have, for the first time, made it possible for us to quantitatively characterize the impact of wildfires on atmospheric CO_2 in California, which revealed that atmospheric CO_2 increased by 2 ppm after the October 2017 California wildfires. Analyses in this study can help us better understand the causes and impacts of wildfires.", "date": "2019-08", "date_type": "published", "publication": "Earth and Space Science", "volume": "6", "number": "8", "publisher": "American Geophysical Union", "pagerange": "1480-1488", "id_number": "CaltechAUTHORS:20190805-104042393", "issn": "2333-5084", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190805-104042393", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA/JPL" } ] }, "local_group": { "items": [ { "id": "Astronomy-Department" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2019ea000661", "primary_object": { "basename": "Li_et_al-2019-Earth_and_Space_Science.pdf", "url": "https://authors.library.caltech.edu/records/1dn56-p6v27/files/Li_et_al-2019-Earth_and_Space_Science.pdf" }, "related_objects": [ { "basename": "ess2358-sup-0001-2019ea000661-si.docx", "url": "https://authors.library.caltech.edu/records/1dn56-p6v27/files/ess2358-sup-0001-2019ea000661-si.docx" } ], "resource_type": "article", "pub_year": "2019", "author_list": "Li, Andy X.; Wang, Yuan; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/40xst-0ex24", "eprint_id": 97168, "eprint_status": "archive", "datestamp": "2023-08-22 02:05:57", "lastmod": "2023-10-20 22:01:19", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "He-Liyin", "name": { "family": "He", "given": "Liyin" }, "orcid": "0000-0003-4427-1438" }, { "id": "Zeng-Zhao\u2010Cheng", "name": { "family": "Zeng", "given": "Zhao\u2010Cheng" }, "orcid": "0000-0002-0008-6508" }, { "id": "Pongetti-T-J", "name": { "family": "Pongetti", "given": "Thomas" }, "orcid": "0000-0001-9465-0853" }, { "id": "Wong-Clare-K", "name": { "family": "Wong", "given": "Clare" } }, { "id": "Liang-Jianming", "name": { "family": "Liang", "given": "Jianming" }, "orcid": "0000-0002-4043-6816" }, { "id": "Gurney-K-R", "name": { "family": "Gurney", "given": "Kevin R." }, "orcid": "0000-0001-9218-7164" }, { "id": "Newman-S", "name": { "family": "Newman", "given": "Sally" }, "orcid": "0000-0003-0710-995X" }, { "id": "Yadav-V", "name": { "family": "Yadav", "given": "Vineet" }, "orcid": "0000-0002-2805-3345" }, { "id": "Verhulst-K-R", "name": { "family": "Verhulst", "given": "Kristal" }, "orcid": "0000-0001-5678-9678" }, { "id": "Miller-C-E", "name": { "family": "Miller", "given": "Charles E." }, "orcid": "0000-0002-9380-4838" }, { "id": "Duren-R", "name": { "family": "Duren", "given": "Riley" }, "orcid": "0000-0003-4723-5280" }, { "id": "Frankenberg-C", "name": { "family": "Frankenberg", "given": "Christian" }, "orcid": "0000-0002-0546-5857" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul" }, "orcid": "0000-0002-6126-3854" }, { "id": "Shia-Run\u2010Lie", "name": { "family": "Shia", "given": "Run\u2010Lie" }, "orcid": "0000-0003-1911-3120" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Sander-S-P", "name": { "family": "Sander", "given": "Stanley P." }, "orcid": "0000-0003-1424-3620" } ] }, "title": "Atmospheric methane emissions correlate with natural gas consumption from residential and commercial sectors in Los Angeles", "ispublished": "pub", "full_text_status": "public", "keywords": "methane emissions; greenhouse gas; urban pollution; natural gas leakage", "note": "\u00a9 2019 American Geophysical Union. \n\nReceived 19 APR 2019; Accepted 10 JUL 2019; Accepted article online 15 JUL 2019. \n\nThis research was supported by NIST, CARB, and NASA. We gratefully acknowledge discussions with M. Fischer, G. Heath, J. Hedelius, M. Weitz, and V. Camobreco. L.H. thanks the Resnick Sustainability Institute at Caltech for fellowship support. We thank A. Andrews and E. Dlugokencky for providing the NOAA flask measurements at Mt. Wilson Observatory (National Oceanic and Atmospheric Administration, 2019). CLARS\u2010FTS data are available from the NASA Megacities Project (https://megacities.jpl.nasa.gov). The research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration. L. H., Z. C. Z., T. P., C. W., and S. S. carried out the data acquisition and analysis, J. L. and K. G. provided the Hestia inventory, S. S., L. H., and Z. C. Z. wrote the paper, and all authors contributed to the analysis and discussion of the results. The authors declare no competing financial interests.\n\nPublished - He_et_al-2019-Geophysical_Research_Letters.pdf
Supplemental Material - grl59321-sup-0001-2019gl083400-s01.docx
", "abstract": "Legislation in the State of California mandates reductions in emissions of short\u2010lived climate pollutants of 40% from 2013 levels by 2030 for CH_4. Identification of the sector(s) responsible for these emissions and their temporal and spatial variability is a key step in achieving these goals. Here, we determine the emissions of CH_4 in Los Angeles from 2011\u20132017 using a mountaintop remote sensing mapping spectrometer. We show that the pattern of CH_4 emissions contains both seasonal and nonseasonal contributions. We find that the seasonal component peaks in the winter and is correlated (R^2 = 0.58) with utility natural gas consumption from the residential and commercial sectors and not from the industrial and gas\u2010fired power plant sectors. The nonseasonal component is (22.9 \u00b1 1.4) Gg CH_4/month. If the seasonal correlation is causal, about (1.4 \u00b1 0.1)% of the commercial and residential natural gas consumption in Los Angeles is released into the atmosphere.", "date": "2019-07-28", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "46", "number": "14", "publisher": "American Geophysical Union", "pagerange": "8563-8571", "id_number": "CaltechAUTHORS:20190716-102712163", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190716-102712163", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "National Institute of Standards and Technology (NIST)" }, { "agency": "California Air Resources Board" }, { "agency": "NASA/JPL/Caltech" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "Astronomy-Department" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2019gl083400", "primary_object": { "basename": "He_et_al-2019-Geophysical_Research_Letters.pdf", "url": "https://authors.library.caltech.edu/records/40xst-0ex24/files/He_et_al-2019-Geophysical_Research_Letters.pdf" }, "related_objects": [ { "basename": "grl59321-sup-0001-2019gl083400-s01.docx", "url": "https://authors.library.caltech.edu/records/40xst-0ex24/files/grl59321-sup-0001-2019gl083400-s01.docx" } ], "resource_type": "article", "pub_year": "2019", "author_list": "He, Liyin; Zeng, Zhao\u2010Cheng; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/ey73a-3h171", "eprint_id": 100500, "eprint_status": "archive", "datestamp": "2023-08-19 16:49:55", "lastmod": "2023-10-18 20:56:10", "type": "book_section", "metadata_visibility": "show", "creators": { "items": [ { "id": "Bartlett-S", "name": { "family": "Bartlett", "given": "Stuart" }, "orcid": "0000-0001-5680-476X" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Attractor Landscapes and Information Processing by Convective Obstacle Flows", "ispublished": "unpub", "full_text_status": "public", "note": "\u00a9 2019 Massachusetts Institute of Technology Published under a Creative Commons Attribution 4.0 International (CC BY 4.0) license. \n\nPosted Online July 15, 2019.\n\nPublished - isal_a_00169.pdf
", "abstract": "We present recent results concerning the attractor landscape, memory, hysteresis and computation that can emerge in simple convective obstacle flows. In these systems a single phase fluid is heated from below and cooled from above. Small obstacles (one or two) are placed on the horizontal mid plane of the system and extract some fraction of the fluid's horizontal or vertical momentum. Horizontal momentum sinks tend to attract convection plumes. Vertical momentum sinks are bistable; the obstacle will either align with a convection cell centre or convection plume depending on initial conditions and the history of the system. The resulting attractor landscape can be exploited to produce a single bit memory or even elementary Boolean logic.", "date": "2019-07-22", "date_type": "published", "publisher": "MIT Press", "place_of_pub": "Cambridge, MA", "pagerange": "245-246", "id_number": "CaltechAUTHORS:20200103-110201113", "isbn": "9780262358446", "book_title": "ALIFE 2019: the 2019 Conference on Artificial Life", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200103-110201113", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "local_group": { "items": [ { "id": "Astronomy-Department" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1162/isal_a_00169", "primary_object": { "basename": "isal_a_00169.pdf", "url": "https://authors.library.caltech.edu/records/ey73a-3h171/files/isal_a_00169.pdf" }, "resource_type": "book_section", "pub_year": "2019", "author_list": "Bartlett, Stuart and Yung, Yuk L." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/29dzj-m0j60", "eprint_id": 97061, "eprint_status": "archive", "datestamp": "2023-08-22 01:57:20", "lastmod": "2023-10-20 21:54:05", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Long-Junyang", "name": { "family": "Long", "given": "Junyang" } }, { "id": "Jiang-Jonathan-H", "name": { "family": "Jiang", "given": "Jonathan H." }, "orcid": "0000-0002-5929-8951" }, { "id": "Fan-Siteng", "name": { "family": "Fan", "given": "Siteng" }, "orcid": "0000-0002-3041-4680" }, { "id": "Jiang-Xun", "name": { "family": "Jiang", "given": "Xun" }, "orcid": "0000-0001-8932-3807" }, { "id": "Shia-Run\u2010Lie", "name": { "family": "Shia", "given": "Run\u2010Lie" }, "orcid": "0000-0003-1911-3120" } ] }, "title": "Effect of the Quasi-biennial Oscillation on Carbon Monoxide in the Stratosphere", "ispublished": "pub", "full_text_status": "public", "keywords": "Quasi\u2010biennial Oscillation; Microwave Limb Sounder CO; Chemistry Transport Model", "note": "\u00a9 2019 American Geophysical Union. This is an open access article under the terms of the Creative Commons Attribution\u2010NonCommercial\u2010NoDerivs License, which permits use and distribution in any medium, provided the original work is properly cited, the use is non\u2010commercial and no modifications or adaptations are made. \n\nReceived 4 DEC 2018; Accepted 20 JUN 2019; Accepted article online 8 JUL 2019. \n\nWe thank J. N. Lee, K.-F. Li, A. Ruzmaikin and S. Wang for illuminating discussions. We thank the MLS project for the CO data and JPL for support of this work. We also acknowledge the use of the following data. \n\nNCEP2 Reanalysis data [Kistler et al., 2001] can be downloaded at https://www.esrl.noaa.gov/psd/data/gridded/data.ncep.reanalysis2.html. \n\nThe QBO winds over Singapore can be downloaded from\nhttp://www.geo.fu-berlin.de/met/ag/strat/produkte/qbo/qbo.dat.\n\nPublished - Yung_et_al-2019-Earth_and_Space_Science.pdf
Supplemental Material - ess2340-sup-0001-2018ea000534-s01.docx
Supplemental Material - ess2340-sup-0002-2018ea000534-fs01.eps
Supplemental Material - ess2340-sup-0003-2018ea000534-fs02.eps
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Supplemental Material - ess2340-sup-0010-2018ea000534-fs09.eps
", "abstract": "The interannual variability of tropical carbon monoxide (CO) from the Microwave Limb Sounder (MLS) over 2004\u20102018 period is dominated by the Quasi\u2010biennial Oscillation (QBO). We simulate the CO variability over this period using the 2\u2010D Caltech/JPL chemistry\u2010transport model (CTM). The CTM includes the photochemical sources and sinks and transport driven by a stream function and eddy diffusivity derived from the assimilated winds of National Centers for Environmental Prediction Reanalysis 2. The results show good agreement between model and MLS observations. We also investigate the anomalous period 2015\u20102016, when the QBO winds deviated significantly from their climatological values. The model simulations could capture the QBO features in agreement with observations for the anomalous period.", "date": "2019-07", "date_type": "published", "publication": "Earth and Space Science", "volume": "6", "number": "7", "publisher": "American Geophysical Union", "pagerange": "1273-1283", "id_number": "CaltechAUTHORS:20190711-133439083", "issn": "2333-5084", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190711-133439083", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "local_group": { "items": [ { "id": "Astronomy-Department" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2018ea000534", "primary_object": { "basename": "ess2340-sup-0002-2018ea000534-fs01.eps", "url": "https://authors.library.caltech.edu/records/29dzj-m0j60/files/ess2340-sup-0002-2018ea000534-fs01.eps" }, "related_objects": [ { "basename": "ess2340-sup-0004-2018ea000534-fs03.eps", "url": "https://authors.library.caltech.edu/records/29dzj-m0j60/files/ess2340-sup-0004-2018ea000534-fs03.eps" }, { "basename": "ess2340-sup-0005-2018ea000534-fs04.eps", "url": "https://authors.library.caltech.edu/records/29dzj-m0j60/files/ess2340-sup-0005-2018ea000534-fs04.eps" }, { "basename": "ess2340-sup-0007-2018ea000534-fs06.eps", "url": "https://authors.library.caltech.edu/records/29dzj-m0j60/files/ess2340-sup-0007-2018ea000534-fs06.eps" }, { "basename": "ess2340-sup-0010-2018ea000534-fs09.eps", "url": "https://authors.library.caltech.edu/records/29dzj-m0j60/files/ess2340-sup-0010-2018ea000534-fs09.eps" }, { "basename": "Yung_et_al-2019-Earth_and_Space_Science.pdf", "url": "https://authors.library.caltech.edu/records/29dzj-m0j60/files/Yung_et_al-2019-Earth_and_Space_Science.pdf" }, { "basename": "ess2340-sup-0003-2018ea000534-fs02.eps", "url": "https://authors.library.caltech.edu/records/29dzj-m0j60/files/ess2340-sup-0003-2018ea000534-fs02.eps" }, { "basename": "ess2340-sup-0006-2018ea000534-fs05.eps", "url": "https://authors.library.caltech.edu/records/29dzj-m0j60/files/ess2340-sup-0006-2018ea000534-fs05.eps" }, { "basename": "ess2340-sup-0008-2018ea000534-fs07.eps", "url": "https://authors.library.caltech.edu/records/29dzj-m0j60/files/ess2340-sup-0008-2018ea000534-fs07.eps" }, { "basename": "ess2340-sup-0009-2018ea000534-fs08.eps", "url": "https://authors.library.caltech.edu/records/29dzj-m0j60/files/ess2340-sup-0009-2018ea000534-fs08.eps" }, { "basename": "ess2340-sup-0001-2018ea000534-s01.docx", "url": "https://authors.library.caltech.edu/records/29dzj-m0j60/files/ess2340-sup-0001-2018ea000534-s01.docx" } ], "resource_type": "article", "pub_year": "2019", "author_list": "Yung, Yuk L.; Long, Junyang; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/xx8ak-s3w88", "eprint_id": 95696, "eprint_status": "archive", "datestamp": "2023-08-19 16:28:58", "lastmod": "2023-10-20 20:28:12", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Fan-Siteng", "name": { "family": "Fan", "given": "Siteng" }, "orcid": "0000-0002-3041-4680" }, { "id": "Shemansky-D-E", "name": { "family": "Shemansky", "given": "Donald E." }, "orcid": "0000-0001-7168-871X" }, { "id": "Li-Cheng", "name": { "family": "Li", "given": "Cheng" }, "orcid": "0000-0002-8280-3119" }, { "id": "Gao-Peter", "name": { "family": "Gao", "given": "Peter" }, "orcid": "0000-0002-8518-9601" }, { "id": "Wan-Linfeng", "name": { "family": "Wan", "given": "Linfeng" }, "orcid": "0000-0002-3762-5034" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Retrieval of Chemical Abundances in Titan's Upper Atmosphere from Cassini UVIS Observations with Pointing Motion", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2019 American Geophysical Union. This is an open access article under the terms of the Creative Commons Attribution\u2010NonCommercial\u2010NoDerivs License, which permits use and distribution in any medium, provided the original work is properly cited, the use is non\u2010commercial and no modifications or adaptations are made. \n\nReceived 18 SEP 2018; Accepted 8 MAY 2019; Accepted article online 22 MAY 2019. \n\nThis research was supported in part by the Cassini/UVIS program via NASA grant JPL.1459109 to the California Institute of Technology, and was partially supported by funding from NASA's Astrobiology Institute's proposal \"Habitability of Hydrocarbon Worlds: Titan and Beyond\" (PI R.M. Lopes). All the data and tools in this work are publicly available. Cassini/UVIS data is available on NASA PDS (pds.nasa.gov). The python package emcee is available at dfm.io/emcee/current. We thank Dr. Tommi T. Koskinen and Dr. Karen Willacy for sharing results.\n\nPublished - Fan_et_al-2019-Earth_and_Space_Science.pdf
Accepted Version - 1906.02230.pdf
Supplemental Material - ess2_310-sup-0001-2018ea000477-si.docx
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Supplemental Material - ess2_310-sup-0003-2018ea000477-fs02.eps
Supplemental Material - ess2_310-sup-0004-2018ea000477-fs03.eps
Supplemental Material - ess2_310-sup-0005-2018ea000477-fs04.eps
Supplemental Material - ess2_310-sup-0006-2018ea000477-fs05.eps
Supplemental Material - ess2_310-sup-0007-2018ea000477-ds01.csv
Supplemental Material - ess2_310-sup-0008-2018ea000477-ds02.csv
", "abstract": "Cassini/UVIS FUV observations of stellar occultations at Titan are well suited for probing its atmospheric composition and structure. However, due to instrument pointing motion, only five out of tens of observations have been analyzed. We present an innovative retrieval method that corrects for the effect of pointing motion by forward modeling the Cassini/UVIS instrument response function with the pointing motion value obtained from the SPICE C\u2010kernel along the spectral dimension. To illustrate the methodology, an occultation observation made during flyby T52 is analyzed, when the Cassini spacecraft had insufficient attitude control. A high\u2010resolution stellar model and an instrument response simulator that includes the position of the point source on the detector are used for the analysis of the pointing motion. The Markov Chain Monte\u2010Carlo method is used to retrieve the line\u2010of\u2010sight abundance profiles of eleven species (CH_4, C_2H_2, C_2H_4, C_2H_6, C_4H_2, C_6H_6, HCN, C_2N_2, HC_3N, C_6N_2 and haze particles) in the spectral vector fitting process. We obtain tight constraints on all of the species aside from C_2H_6, C_2N_2 and C_6N_2, for which we only retrieved upper limits. This is the first time that the T52 occultation was used to derive abundances of major hydrocarbon and nitrile species in Titan's upper and middle atmosphere, as pointing motion prohibited prior analysis. With this new method, nearly all of the occultations obtained over the entire Cassini mission could yield reliable profiles of atmospheric composition, allowing exploration of Titan's upper atmosphere over seasons, latitudes, and longitudes.", "date": "2019-07", "date_type": "published", "publication": "Earth and Space Science", "volume": "6", "number": "7", "publisher": "American Geophysical Union", "pagerange": "1057-1066", "id_number": "CaltechAUTHORS:20190522-105635213", "issn": "2333-5084", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190522-105635213", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "JPL.1459109" } ] }, "local_group": { "items": [ { "id": "Astronomy-Department" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2018EA000477", "primary_object": { "basename": "Fan_et_al-2019-Earth_and_Space_Science.pdf", "url": "https://authors.library.caltech.edu/records/xx8ak-s3w88/files/Fan_et_al-2019-Earth_and_Space_Science.pdf" }, "related_objects": [ { "basename": "ess2_310-sup-0001-2018ea000477-si.docx", "url": "https://authors.library.caltech.edu/records/xx8ak-s3w88/files/ess2_310-sup-0001-2018ea000477-si.docx" }, { "basename": "ess2_310-sup-0002-2018ea000477-fs01.eps", "url": "https://authors.library.caltech.edu/records/xx8ak-s3w88/files/ess2_310-sup-0002-2018ea000477-fs01.eps" }, { "basename": "ess2_310-sup-0003-2018ea000477-fs02.eps", "url": "https://authors.library.caltech.edu/records/xx8ak-s3w88/files/ess2_310-sup-0003-2018ea000477-fs02.eps" }, { "basename": "ess2_310-sup-0004-2018ea000477-fs03.eps", "url": "https://authors.library.caltech.edu/records/xx8ak-s3w88/files/ess2_310-sup-0004-2018ea000477-fs03.eps" }, { "basename": "ess2_310-sup-0006-2018ea000477-fs05.eps", "url": "https://authors.library.caltech.edu/records/xx8ak-s3w88/files/ess2_310-sup-0006-2018ea000477-fs05.eps" }, { "basename": "ess2_310-sup-0007-2018ea000477-ds01.csv", "url": "https://authors.library.caltech.edu/records/xx8ak-s3w88/files/ess2_310-sup-0007-2018ea000477-ds01.csv" }, { "basename": "1906.02230.pdf", "url": "https://authors.library.caltech.edu/records/xx8ak-s3w88/files/1906.02230.pdf" }, { "basename": "ess2_310-sup-0008-2018ea000477-ds02.csv", "url": "https://authors.library.caltech.edu/records/xx8ak-s3w88/files/ess2_310-sup-0008-2018ea000477-ds02.csv" }, { "basename": "ess2_310-sup-0005-2018ea000477-fs04.eps", "url": "https://authors.library.caltech.edu/records/xx8ak-s3w88/files/ess2_310-sup-0005-2018ea000477-fs04.eps" } ], "resource_type": "article", "pub_year": "2019", "author_list": "Fan, Siteng; Shemansky, Donald E.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/348d5-q9x58", "eprint_id": 94558, "eprint_status": "archive", "datestamp": "2023-08-22 01:50:50", "lastmod": "2023-10-20 18:04:16", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Wang-Jianjie", "name": { "family": "Wang", "given": "Jianjie" } }, { "id": "Liu-Chao", "name": { "family": "Liu", "given": "Chao" }, "orcid": "0000-0001-7049-493X" }, { "id": "Yao-Bin", "name": { "family": "Yao", "given": "Bin" } }, { "id": "Min-Min", "name": { "family": "Min", "given": "Min" }, "orcid": "0000-0003-1519-5069" }, { "id": "Letu-Husi", "name": { "family": "Letu", "given": "Husi" }, "orcid": "0000-0002-7336-8872" }, { "id": "Yin-Yan", "name": { "family": "Yin", "given": "Yan" }, "orcid": "0000-0002-8391-2712" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "A multilayer cloud detection algorithm for the Suomi-NPP Visible Infrared Imager Radiometer Suite (VIIRS)", "ispublished": "pub", "full_text_status": "restricted", "keywords": "VIIRS; Multilayer clouds; Radiometer; Shortwave infrared; Longwave infrared", "note": "\u00a9 2019 Elsevier. \n\nReceived 11 July 2018, Revised 22 February 2019, Accepted 23 February 2019, Available online 6 April 2019. \n\nThis research is supported by the National Key Research and Development Program of China (2018YFC1506502), the National Natural Science Foundation of China (41571348 and 41771395), Young Elite Scientists Sponsorship Program by CAST (2017QNRC001), the Six Talent Peaks Project in Jiangsu Province (2017-JY-053), and the Open Project Fund of Key Laboratory of Radiometric Calibration and Validation for Environmental Satellites, NSMC/CMA.", "abstract": "A new multilayer (ML) cloud detection algorithm based on three shortwave infrared (SWIR) and two longwave infrared (LWIR) channels is developed and applied to the Visible Infrared Imager Radiometer Suite (VIIRS) onboard the Suomi-NPP satellite. The algorithm identifies ML clouds, i.e., ice clouds overlying water clouds, based on satellite multispectral observations in the 1.38, 1.6, 2.25, 8.5, and 11\u202f\u03bcm channels. We perform synthetic radiative transfer simulations to understand the sensitivities of the aforementioned channels on ML and single-layer (SL) clouds. Active CALIOP observations are used to evaluate the algorithm. Compared with the collocated CALIOP results, the algorithm can determine SL and ML clouds correctly with success rates of approximately 80% and 60%, respectively, and has similar performance to that of the current MODIS operational ML cloud detection algorithm. The misclassification of ML clouds as SL clouds is primarily caused by thin ice clouds that are practically undetectable using LWIR tests. Furthermore, the algorithm is extended to analyze data from radiometers onboard the geostationary Himawari-8 and FengYun-4A satellites, and results similar to those of VIIRS are obtained.", "date": "2019-06-15", "date_type": "published", "publication": "Remote Sensing of Environment", "volume": "227", "publisher": "Elsevier", "pagerange": "1-11", "id_number": "CaltechAUTHORS:20190408-101258817", "issn": "0034-4257", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190408-101258817", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "National Key Research and Development Program of China", "grant_number": "2018YFC1506502" }, { "agency": "National Natural Science Foundation of China", "grant_number": "41571348" }, { "agency": "National Natural Science Foundation of China", "grant_number": "41771395" }, { "agency": "Chinese Association for Science and Technology", "grant_number": "2017QNRC001" }, { "agency": "Six Talent Peaks Project in Jiangsu Province", "grant_number": "2017-JY-053" }, { "agency": "Open Project Fund of Key Laboratory of Radiometric Calibration and Validation for Environmental Satellites" } ] }, "local_group": { "items": [ { "id": "Astronomy-Department" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/j.rse.2019.02.024", "resource_type": "article", "pub_year": "2019", "author_list": "Wang, Jianjie; Liu, Chao; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/pt4ge-d3616", "eprint_id": 96029, "eprint_status": "archive", "datestamp": "2023-08-19 15:56:45", "lastmod": "2023-10-20 20:49:10", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Liu-Huan", "name": { "family": "Liu", "given": "Huan" } }, { "id": "Guo-Jianping", "name": { "family": "Guo", "given": "Jianping" }, "orcid": "0000-0001-8530-8976" }, { "id": "Koren-Ilan", "name": { "family": "Koren", "given": "Ilan" }, "orcid": "0000-0001-6759-6265" }, { "id": "Altaratz-Orit", "name": { "family": "Altaratz", "given": "Orit" } }, { "id": "Dagan-Guy", "name": { "family": "Dagan", "given": "Guy" } }, { "id": "Wang-Yuan", "name": { "family": "Wang", "given": "Yuan" }, "orcid": "0000-0001-6657-8401" }, { "id": "Jiang-Jonathan-H", "name": { "family": "Jiang", "given": "Jonathan H." }, "orcid": "0000-0002-5929-8951" }, { "id": "Zhai-Panmao", "name": { "family": "Zhai", "given": "Panmao" } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Non-Monotonic Aerosol Effect on Precipitation in Convective Clouds over Tropical Oceans", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2019 The Author(s). This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/. \n\nReceived 11 January 2019; Accepted 14 May 2019; Published 24 May 2019. \n\nData Availability: All observational datasets used in this study are publicly available. The numerical results are available from the corresponding author upon request. \n\nThe authors would like to thank Z. Li for help with the analyses of satellite aerosol and precipitation, and T. Nakajima for advice on the response of precipitation to aerosols. We acknowledge the European Centre for Medium-Range Weather Forecasts (ECMWF) for providing the reanalysis data for this study, and NASA for making the TRMM precipitation radar satellite datasets publicly accessible. H.L. and J.G. were supported by the Ministry of Science and Technology of China under grant 2017YFC1501401, and the National Natural Science Foundation of China under grant 41771399. I.K., O.A., G.D. and H.L. were supported by the Ministry of Science and Technology, Israel (Grant No. 3\u201314444). Y.W., J.H.J. and Y.L.Y. were supported by the NASA-sponsored Jet Propulsion Laboratory, California Institute of Technology. \n\nAuthor Contributions: J.G., I.K. and P.Z. designed the study. Data were analyzed by H.L. and G.D. Model simulations were run by G.D. The manuscript was written by H.L., I.K., J.G., O.A., G.D., J.H.J., Y.L.Y. and Y.W. \n\nThe authors declare no competing interests.\n\nPublished - s41598-019-44284-2.pdf
Supplemental Material - 41598_2019_44284_MOESM1_ESM.pdf
", "abstract": "Aerosol effects on convective clouds and associated precipitation constitute an important open-ended question in climate research. Previous studies have linked an increase in aerosol concentration to a delay in the onset of rain, invigorated clouds and stronger rain rates. Here, using observational data, we show that the aerosol effect on convective clouds shifts from invigoration to suppression with increasing aerosol optical depth. We explain this shift in trend (using a cloud model) as the result of a competition between two types of microphysical processes: cloud-core-based invigorating processes vs. peripheral suppressive processes. We show that the aerosol optical depth value that marks the shift between invigoration and suppression depends on the environmental thermodynamic conditions. These findings can aid in better parameterizing aerosol effects in climate models for the prediction of climate trends.", "date": "2019-05-24", "date_type": "published", "publication": "Scientific Reports", "volume": "9", "publisher": "Nature Publishing Group", "pagerange": "Art. No. 7809", "id_number": "CaltechAUTHORS:20190603-093109450", "issn": "2045-2322", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190603-093109450", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Ministry of Science and Technology (Taipei)", "grant_number": "2017YFC1501401" }, { "agency": "National Natural Science Foundation of China", "grant_number": "41771399" }, { "agency": "Ministry of Science and Technology (Israel)", "grant_number": "3\u201314444" }, { "agency": "NASA/JPL/Caltech" } ] }, "local_group": { "items": [ { "id": "Astronomy-Department" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1038/s41598-019-44284-2", "pmcid": "PMC6534586", "primary_object": { "basename": "41598_2019_44284_MOESM1_ESM.pdf", "url": "https://authors.library.caltech.edu/records/pt4ge-d3616/files/41598_2019_44284_MOESM1_ESM.pdf" }, "related_objects": [ { "basename": "s41598-019-44284-2.pdf", "url": "https://authors.library.caltech.edu/records/pt4ge-d3616/files/s41598-019-44284-2.pdf" } ], "resource_type": "article", "pub_year": "2019", "author_list": "Liu, Huan; Guo, Jianping; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/9n6pf-2r988", "eprint_id": 96576, "eprint_status": "archive", "datestamp": "2023-08-19 15:40:11", "lastmod": "2023-10-20 21:19:05", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Jiang-Xun", "name": { "family": "Jiang", "given": "Xun" }, "orcid": "0000-0001-8932-3807" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Global Patterns of Carbon Dioxide Variability from Satellite Observations", "ispublished": "pub", "full_text_status": "restricted", "keywords": "CO2 annual cycle, CO2 semiannual cycle, intraseasonal variability, monsoon, El Ni\u00f1o\u2013Southern Oscillation, Northern Annular Mode, drought, wildfire", "note": "\u00a9 2019 Annual Reviews. \n\nFirst published as a Review in Advance on January 11, 2019. \n\nWe thank the anonymous reviewer and Co-Editors for their time and helpful comments. We thank D. Crisp, A. Eldering, M. Gunson, C. Miller, E. Olsen, and T. Pagano for discussions and G. Chen, K.-F. Li,M.-C. Liang, V. Natraj, S. Newman, R.-L. Shia, Y.Wang, and Z.-C. Zeng for critical reading of the manuscript.We also thank K. Jucks for many years of support via the NASA OCO-2 project. \n\nThe authors are not aware of any affiliations, memberships, funding, or financial holdings that might be perceived as affecting the objectivity of this review.", "abstract": "Advanced satellite technology has been providing unique observations of global carbon dioxide (CO_2) concentrations. These observations have revealed important CO_2 variability at different timescales and over regional and planetary scales. Satellite CO_2 retrievals have revealed that stratospheric sudden warming and the Madden-Julian Oscillation can modulate atmospheric CO_2 concentrations in the mid-troposphere. Atmospheric CO_2 also demonstrates variability at interannual timescales. In the tropical region, the El Ni\u00f1o\u2013Southern Oscillation and the Tropospheric Biennial Oscillation can change atmospheric CO_2 concentrations. At high latitudes, mid-tropospheric CO_2 concentrations can be influenced by the Northern Hemispheric annular mode. In addition to modulations by the large-scale circulations, sporadic events such as wildfires, volcanic eruptions, and droughts, which change CO_2 surface emissions, can cause atmospheric CO_2 concentrations to increase significantly. The natural variability of CO_2 summarized in this review can help us better understand its sources and sinks and its redistribution by atmospheric motion.", "date": "2019-05", "date_type": "published", "publication": "Annual Review of Earth and Planetary Sciences", "volume": "47", "publisher": "Annual Reviews", "pagerange": "225-245", "id_number": "CaltechAUTHORS:20190620-081112875", "issn": "0084-6597", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190620-081112875", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "local_group": { "items": [ { "id": "Astronomy-Department" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1146/annurev-earth-053018-060447", "resource_type": "article", "pub_year": "2019", "author_list": "Jiang, Xun and Yung, Yuk L." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/04zq3-yzt64", "eprint_id": 93437, "eprint_status": "archive", "datestamp": "2023-08-19 14:31:01", "lastmod": "2023-10-20 17:08:43", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Bartlett-S-J", "name": { "family": "Bartlett", "given": "S. J." }, "orcid": "0000-0001-5680-476X" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Y. L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Convective flow in the presence of a small obstacle: Symmetry breaking, attractors, hysteresis, and information", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2019 American Physical Society. \n\n(Received 27 June 2018; revised manuscript received 11 February 2019; published 4 March 2019) \n\nThis work was supported by the Earth Life Science Institute Origins Network (EON) Postdoctoral Fellowship Program and the Caltech Division of Geological and Planetary Sciences Discovery Fund.\n\nPublished - PhysRevE.99.033103.pdf
", "abstract": "This work explores the stability and hysteresis effects that occur when a small sink of momentum is introduced into a heat-driven, two-dimensional convective flow. As per standard fluid mechanical intuition, the system minimizes work generation and dissipation when one component of momentum is extracted. However, when the sink absorbs all incoming momentum, the system configures itself such that one of the convection plumes aligns directly with the sink. This state is the most hydrodynamically stable, but it maximizes, rather than minimizes extracted mechanical work. Furthermore, in the case of only vertical momentum extraction, there are two attractors, with different stabilities. Numerical experiments involving slow variations of the horizontal momentum extraction show a clear history dependence. This hysteresis preserves information about the system's past states, and hence represents a primitive memory. The momentum sink can also be used to manipulate the horizontal position of the flow field, with potential applications in microfluidics and laminar convection systems. This simple system exhibits the phenomena of autocatalysis (during the initial growth of the convection plumes), negative feedback (the attractors are either fully or quasistable), memory, and elementary computation.", "date": "2019-03", "date_type": "published", "publication": "Physical Review E", "volume": "99", "number": "3", "publisher": "American Physical Society", "pagerange": "Art. No. 033103", "id_number": "CaltechAUTHORS:20190304-115857803", "issn": "2470-0045", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190304-115857803", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Earth-Life Science Institute" }, { "agency": "Caltech Division of Geological and Planetary Sciences" } ] }, "local_group": { "items": [ { "id": "Astronomy-Department" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1103/physreve.99.033103", "primary_object": { "basename": "PhysRevE.99.033103.pdf", "url": "https://authors.library.caltech.edu/records/04zq3-yzt64/files/PhysRevE.99.033103.pdf" }, "resource_type": "article", "pub_year": "2019", "author_list": "Bartlett, S. J. and Yung, Y. L." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/f7f4k-36v92", "eprint_id": 90282, "eprint_status": "archive", "datestamp": "2023-08-22 00:32:33", "lastmod": "2023-10-18 23:20:26", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Liu-Chao", "name": { "family": "Liu", "given": "Chao" }, "orcid": "0000-0001-7049-493X" }, { "id": "Xu-Xiaofeng", "name": { "family": "Xu", "given": "Xiaofeng" } }, { "id": "Yin-Yan", "name": { "family": "Yin", "given": "Yan" }, "orcid": "0000-0002-8391-2712" }, { "id": "Schnaiter-M", "name": { "family": "Schnaiter", "given": "Martin" }, "orcid": "0000-0002-9560-8072" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Black Carbon Aggregates: A Database for Optical Properties", "ispublished": "pub", "full_text_status": "public", "keywords": "Black carbon; fractal aggregate; optical properties", "note": "\u00a9 2018 Elsevier Ltd. \n\nReceived 5 July 2018, Revised 12 October 2018, Accepted 14 October 2018, Available online 16 October 2018. \n\nThe database developed in this study is available upon request from Chao Liu (chao_liu@nuist.edu.cn). We thank Daniel W. Mackowski and Michael I. Mishchenko for the MSTM code. This work was supported by the R&D Special Fund for Public Welfare of China (Meteorology) (GYHY201506002), the Natural Science Foundation of China (41505018), the Young Elite Scientists Sponsorship Program by CAST (2017QNRC001), the State Scholarship Fund by the China Scholarship Council (201708320049), and the Helmholtz Research Program Atmosphere and Climate. The computation of this study was supported by the National Supercomputer Center in Guangzhou (NSCC-GZ).\n\nSupplemental Material - 1-s2.0-S0022407318304722-mmc1.zip
", "abstract": "Black carbon (BC) aerosol plays an important role in the atmosphere as an absorber of solar radiation and contributes significantly to global warming. The optical properties of BC are fundamental for both direct radiative effect studies and remote sensing of BC properties. However, due to the complex aggregation structures of BC particles, accurate simulations of their optical properties are limited and computationally expensive, while equivalent spherical models or approximate methods could easily introduce relative errors up to 30%. This study generates a comprehensive database to calculate aggregate optical properties efficiently and accurately. The database covers a wide range of BC properties including aggregation structure, refractive index, and particle size (both monomer size and number of monomers). An accurate numerical model, i.e. the multiple-sphere T-matrix method, is used to calculate the single-scattering properties of BC clusters in the form of fractal aggregates. By interpolation, the database can be used to give the scattering properties of aggregates with monomer number from 1 up to 3000, monomer size parameter from 0.05 to 0.5, real part of refractive index from 1.2 to 2.0, and imaginary part from 0.2 to 1.0. The relative errors caused by the interpolation are much less than 1% for the single scattering properties. The pre-calculated database and the implementation used to calculate the required aggregate optical properties are publicly available for users interested in remote sensing of BC aerosols and performing radiative effect calculations.", "date": "2019-01", "date_type": "published", "publication": "Journal of Quantitative Spectroscopy and Radiative Transfer", "volume": "222-223", "publisher": "Elsevier", "pagerange": "170-179", "id_number": "CaltechAUTHORS:20181016-134759925", "issn": "0022-4073", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20181016-134759925", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "R&D Special Fund for Public Welfare of China", "grant_number": "GYHY201506002" }, { "agency": "National Natural Science Foundation of China", "grant_number": "41505018" }, { "agency": "Young Elite Scientists Sponsorship Program", "grant_number": "2017QNRC001" }, { "agency": "China Association for Science and Technology" }, { "agency": "China Scholarship Council", "grant_number": "201708320049" }, { "agency": "Helmholtz Research Program Atmosphere and Climate" }, { "agency": "National Supercomputer Center" } ] }, "local_group": { "items": [ { "id": "Astronomy-Department" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/j.jqsrt.2018.10.021", "primary_object": { "basename": "1-s2.0-S0022407318304722-mmc1.zip", "url": "https://authors.library.caltech.edu/records/f7f4k-36v92/files/1-s2.0-S0022407318304722-mmc1.zip" }, "resource_type": "article", "pub_year": "2019", "author_list": "Liu, Chao; Xu, Xiaofeng; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/3v6d5-z7g02", "eprint_id": 90078, "eprint_status": "archive", "datestamp": "2023-08-22 00:23:26", "lastmod": "2023-10-18 23:11:06", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Liu-Chao", "name": { "family": "Liu", "given": "Chao" }, "orcid": "0000-0001-7049-493X" }, { "id": "Teng-Shiwen", "name": { "family": "Teng", "given": "Shiwen" } }, { "id": "Zhu-Yingying", "name": { "family": "Zhu", "given": "Yingying" } }, { "id": "Yurkin-M-A", "name": { "family": "Yurkin", "given": "Maxim A." }, "orcid": "0000-0002-3524-0093" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Performance of the discrete dipole approximation for optical properties of black carbon aggregates", "ispublished": "pub", "full_text_status": "public", "keywords": "Black carbon aggregate; Discrete-dipole approximation; Effective medium approximation", "note": "\u00a9 2018 Elsevier. \n\nReceived 5 September 2018, Revised 28 September 2018, Accepted 29 September 2018, Available online 1 October 2018.", "abstract": "The optical properties of black carbon (BC) are fundamental for radiative transfer and remote sensing. BC geometry is successfully represented by an idealized model named \"fractal aggregate\", and numerous methods are available and widely used to simulate the corresponding optical properties. This study systematically evaluates the performance of the Discrete Dipole Approximation (DDA) for optical simulations of BC aggregates. The Multiple Sphere T-Matrix (MSTM) results are used as references for accuracy evaluation. The differences between the DDA and MSTM can be controlled to be less than 3% by using dipole size much smaller than the monomer size, and the DDA efficiency is sensitive to aggregate structures, e.g. lacy or compact. We find that shape representation for small-sized monomers during DDA discretization leads significant errors, i.e., up to 10%, and relatively large refractive indices of BC also affects the DDA accuracy. However, the MSTM treats the BC monomers as perfect spheres without overlapping, and the imperfect structure that is implicitly introduced in the DDA simulations due to the spatial discretization may be a better representation of realistic BC particles. Moreover, the efficiency of the DDA can be improved by defining dipoles on the particle boundary to have refractive indices given by the effective medium approximation (EMA). This leads to the adequate shape representation even using larger dipole sizes, and results in the DDA accuracy comparable to that of the reference MSTM solution.", "date": "2018-12", "date_type": "published", "publication": "Journal of Quantitative Spectroscopy and Radiative Transfer", "volume": "221", "publisher": "Elsevier", "pagerange": "98-109", "id_number": "CaltechAUTHORS:20181002-104708158", "issn": "0022-4073", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20181002-104708158", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "National Natural Science Foundation of China", "grant_number": "41475005" }, { "agency": "Young Elite Scientists Sponsorship Program", "grant_number": "2017QNRC001" } ] }, "local_group": { "items": [ { "id": "Astronomy-Department" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/j.jqsrt.2018.09.030", "resource_type": "article", "pub_year": "2018", "author_list": "Liu, Chao; Teng, Shiwen; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/dfaes-42815", "eprint_id": 90156, "eprint_status": "archive", "datestamp": "2023-08-22 00:12:52", "lastmod": "2023-10-18 23:14:46", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Zeng-Zhao-Cheng", "name": { "family": "Zeng", "given": "Zhao-Cheng" }, "orcid": "0000-0002-0008-6508" }, { "id": "Natraj-V", "name": { "family": "Natraj", "given": "Vijay" }, "orcid": "0000-0003-3154-9429" }, { "id": "Xu-Feng", "name": { "family": "Xu", "given": "Feng" }, "orcid": "0000-0001-5155-9478" }, { "id": "Pongetti-T-J", "name": { "family": "Pongetti", "given": "Thomas J." }, "orcid": "0000-0001-9465-0853" }, { "id": "Shia-Run-Lie", "name": { "family": "Shia", "given": "Run-Lie" }, "orcid": "0000-0003-1911-3120" }, { "id": "Kort-E-A", "name": { "family": "Kort", "given": "Eric A." }, "orcid": "0000-0003-4940-7541" }, { "id": "Toon-G-C", "name": { "family": "Toon", "given": "Geoffrey C." }, "orcid": "0000-0003-4174-7541" }, { "id": "Sander-S-P", "name": { "family": "Sander", "given": "Stanley P." }, "orcid": "0000-0003-1424-3620" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Constraining Aerosol Vertical Profile in the Boundary Layer Using Hyperspectral Measurements of Oxygen Absorption", "ispublished": "pub", "full_text_status": "public", "keywords": "Aerosol profiling; PBL; Remote Sensing; Hyperspectral; Megacity; CLARS", "note": "\u00a9 2018 American Geophysical Union. \n\nReceived 20 JUN 2018; Accepted 23 SEP 2018; Accepted article online 27 SEP 2018; Published online 12 OCT 2018. \n\nWe thank Jack Margolis, Chao Liu, Yuan Wang, Siteng Fan, Suniti Sanghavi, Mike Gunson, and Annmarie Eldering for stimulating discussions. V. N. acknowledges support from the NASA Earth Science US Participating Investigator program (solicitation NNH16ZDA001N\u2010ESUSPI). F. X. acknowledges support from NASA Remote Sensing Theory program under grant 14\u2010RST14\u20100100. We are also thankful for the support from the Jet Propulsion Laboratory Research and Technology Development Program. Part of the research in this study was performed at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration. The CLARS project receives support from the California Air Resources Board and the NIST GHG and Climate Science Program. The MiniMPL was supported by the KISS Program at Caltech; data are available from the NASA Megacity project data portal: https://megacities.jpl.nasa.gov/portal/. AERONET data for the Caltech site are available from https://aeronet.gsfc.nasa.gov/new_web/photo_db_v3/CalTech.html. We also thank Jochen Stutz from UCLA and his staff for their effort in establishing and maintaining the AERONET Caltech site. CLARS\u2010FTS data are available from the authors upon request, and part of the data are available from the NASA Megacities Project at https://megacities.jpl.nasa.gov. We are grateful to the two anonymous reviewers whose comments helped improve the paper.\n\nPublished - Zeng_et_al-2018-Geophysical_Research_Letters.pdf
Supplemental Material - grl58079-sup-0001-2018gl079286_s01.pdf
", "abstract": "This study attempts to infer aerosol vertical structure in the urban boundary layer using passive hyperspectral measurements. A spectral sorting technique is developed to retrieve total aerosol optical depth (AOD) and effective aerosol layer height (ALH) from hyperspectral measurements in the 1.27\u2010\u03bcm oxygen absorption band by the mountaintop Fourier Transform Spectrometer at the California Laboratory for Atmospheric Remote Sensing instrument (1,673 m above sea level) overlooking the LA basin. Comparison to AOD measurements from Aerosol Robotic Network and aerosol backscatter profile measurements from a Mini MicroPulse Lidar shows agreement, with coefficients of determination (r^2) of 0.74 for AOD and 0.57 for effective ALH. On average, the AOD retrieval has an error of 24.9% and root\u2010mean\u2010square error of 0.013, while the effective ALH retrieval has an error of 7.8% and root\u2010mean\u2010square error of 67.01 m. The proposed method can potentially be applied to existing and future satellite missions with hyperspectral oxygen measurements to constrain aerosol vertical distribution on a global scale.", "date": "2018-10-16", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "45", "number": "19", "publisher": "American Geophysical Union", "pagerange": "10772-10780", "id_number": "CaltechAUTHORS:20181008-135406047", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20181008-135406047", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NNH16ZDA001N-ESUSPI" }, { "agency": "NASA", "grant_number": "14-RST14-0100" }, { "agency": "NASA/JPL/Caltech" }, { "agency": "California Air Resources Board" }, { "agency": "National Institute of Standards and Technology (NIST)" }, { "agency": "Keck Institute for Space Studies (KISS)" } ] }, "local_group": { "items": [ { "id": "Keck-Institute-for-Space-Studies" }, { "id": "Astronomy-Department" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2018gl079286", "primary_object": { "basename": "Zeng_et_al-2018-Geophysical_Research_Letters.pdf", "url": "https://authors.library.caltech.edu/records/dfaes-42815/files/Zeng_et_al-2018-Geophysical_Research_Letters.pdf" }, "related_objects": [ { "basename": "grl58079-sup-0001-2018gl079286_s01.pdf", "url": "https://authors.library.caltech.edu/records/dfaes-42815/files/grl58079-sup-0001-2018gl079286_s01.pdf" } ], "resource_type": "article", "pub_year": "2018", "author_list": "Zeng, Zhao-Cheng; Natraj, Vijay; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/nkkb4-qne48", "eprint_id": 91261, "eprint_status": "archive", "datestamp": "2023-08-22 00:07:48", "lastmod": "2023-10-19 22:21:03", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Wang-Yuan", "name": { "family": "Wang", "given": "Yuan" }, "orcid": "0000-0001-6657-8401" }, { "id": "Ma-Po-Lun", "name": { "family": "Ma", "given": "Po-Lun" }, "orcid": "0000-0003-3109-5316" }, { "id": "Peng-Jianfei", "name": { "family": "Peng", "given": "Jianfei" } }, { "id": "Zhang-Renyi", "name": { "family": "Zhang", "given": "Renyi" }, "orcid": "0000-0001-8708-3862" }, { "id": "Jiang-Jonathan-H", "name": { "family": "Jiang", "given": "Jonathan H." }, "orcid": "0000-0002-5929-8951" }, { "id": "Easter-R-C", "name": { "family": "Easter", "given": "Richard C." }, "orcid": "0000-0002-8602-1464" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Constraining Aging Processes of Black Carbon in the Community Atmosphere Model Using Environmental Chamber Measurements", "ispublished": "pub", "full_text_status": "public", "keywords": "black carbon; GCM; aging parameterization; environmental chamber; radiative forcing", "note": "\u00a92018. The Authors. This is an open access article under the terms of the Creative Commons Attribution\u2010NonCommercial\u2010NoDerivs License, which permits use and distribution in any medium, provided the original work is properly cited, the use is non\u2010commercial and no modifications or adaptations are made. \n\nReceived 28 MAY 2018. Accepted 3 OCT 2018. Accepted article online 8 OCT 2018. Published online 23 OCT 2018. \n\nY. Wang and J. H. Jiang appreciate the support by the NASA ROSES ACMAP and CCST programs and the support from the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration. Y. Wang and Y. L. Yung appreciate the support by the NSF (award 1700727). P.\u2010L. Ma acknowledges the internal support from the Pacific Northwest National Laboratory, which is operated for the Department of Energy by Battelle Memorial Institute under contract DE\u2010AC05\u201076RL01830. The CESM source code can be obtained from http://www.cesm.ucar.edu/. All model and chamber experiment results are stored at our FTP server at California Institute of Technology and available upon request. Please contact Yuan Wang (yuan.wang@caltech.edu) to access those data.\n\nPublished - Wang_et_al-2018-Journal_of_Advances_in_Modeling_Earth_Systems.pdf
", "abstract": "The direct radiative forcing of black carbon aerosol (BC) on the Earth system remains unsettled, largely due to the uncertainty with physical properties of BC throughout their lifecycle. Here we show that ambient chamber measurements of BC properties provide a novel constraint on the crude BC aging representation in climate models. Observational evidence for significant absorption enhancement of BC can be reproduced when the aging processes in the four\u2010mode version of the Modal Aerosol Module (MAM4) aerosol scheme in the Community Atmosphere Model version 5 are calibrated by the recent in situ chamber measurements. An observation\u2010based scaling method is developed in the aging timescale calculation to alleviate the influence of biases in the simulated model chemical composition. Model sensitivity simulations suggest that the different monolayer settings in the BC aging parameterization of MAM4 can cause as large as 26% and 24% differences in BC burden and radiative forcing, respectively. We also find that an increase in coating materials (e.g., sulfate and secondary organic aerosols) reduces BC lifetime by increasing the hygroscopicity of the mixture but enhances its absorption, resulting in a net increase in BC direct radiative forcing. Our results suggest that accurate simulations of BC aging processes as well as other aerosol species are equally important in reducing the uncertainty of BC forcing estimation.", "date": "2018-10", "date_type": "published", "publication": "Journal of Advances in Modeling Earth Systems", "volume": "10", "number": "10", "publisher": "American Geophysical Union", "pagerange": "2514-2526", "id_number": "CaltechAUTHORS:20181127-160003875", "issn": "1942-2466", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20181127-160003875", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA/JPL/Caltech" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC05-76RL01830" }, { "agency": "NSF", "grant_number": "AGS-1700727" } ] }, "local_group": { "items": [ { "id": "Astronomy-Department" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2018ms001387", "pmcid": "PMC6472719", "primary_object": { "basename": "Wang_et_al-2018-Journal_of_Advances_in_Modeling_Earth_Systems.pdf", "url": "https://authors.library.caltech.edu/records/nkkb4-qne48/files/Wang_et_al-2018-Journal_of_Advances_in_Modeling_Earth_Systems.pdf" }, "resource_type": "article", "pub_year": "2018", "author_list": "Wang, Yuan; Ma, Po-Lun; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/6d6dk-78554", "eprint_id": 89898, "eprint_status": "archive", "datestamp": "2023-09-29 01:33:18", "lastmod": "2023-10-24 15:26:55", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Chen-Pin", "name": { "family": "Chen", "given": "Pin" } }, { "id": "Nealson-K-H", "name": { "family": "Nealson", "given": "Kenneth" }, "orcid": "0000-0001-5189-3732" }, { "id": "Atreya-S-K", "name": { "family": "Atreya", "given": "Sushil" }, "orcid": "0000-0002-1972-1815" }, { "id": "Beckett-P", "name": { "family": "Beckett", "given": "Patrick" } }, { "id": "Blank-J-G", "name": { "family": "Blank", "given": "Jennifer G." } }, { "id": "Ehlmann-B-L", "name": { "family": "Ehlmann", "given": "Bethany" }, "orcid": "0000-0002-2745-3240" }, { "id": "Eiler-J-M", "name": { "family": "Eiler", "given": "John" } }, { "id": "Etiope-G", "name": { "family": "Etiope", "given": "Giuseppe" } }, { "id": "Ferry-J-G", "name": { "family": "Ferry", "given": "James G." } }, { "id": "Forget-F", "name": { "family": "Forget", "given": "Fran\u00e7ois" } }, { "id": "Gao-Peter", "name": { "family": "Gao", "given": "Peter" }, "orcid": "0000-0002-8518-9601" }, { "id": "Hu-Renyu", "name": { "family": "Hu", "given": "Renyu" }, "orcid": "0000-0003-2215-8485" }, { "id": "Kleinb\u00f6hl-A", "name": { "family": "Kleinb\u00f6hl", "given": "Armin" } }, { "id": "Klusman-", "name": { "family": "Klusman", "given": "Ronald" } }, { "id": "Lef\u00e8vre-F", "name": { "family": "Lef\u00e8vre", "given": "Franck" } }, { "id": "Miller-C-E", "name": { "family": "Miller", "given": "Charles" }, "orcid": "0000-0002-9380-4838" }, { "id": "Mischna-M-A", "name": { "family": "Mischna", "given": "Michael" }, "orcid": "0000-0002-8022-5319" }, { "id": "Mumma-M-J", "name": { "family": "Mumma", "given": "Michael" } }, { "id": "Newman-S", "name": { "family": "Newman", "given": "Sally" }, "orcid": "0000-0003-0710-995X" }, { "id": "Oehler-D-Z", "name": { "family": "Oehler", "given": "Dorothy" } }, { "id": "Okumura-M", "name": { "family": "Okumura", "given": "Mitchio" }, "orcid": "0000-0001-6874-1137" }, { "id": "Oremland-R-S", "name": { "family": "Oremland", "given": "Ronald" } }, { "id": "Orphan-V-J", "name": { "family": "Orphan", "given": "Victoria" }, "orcid": "0000-0002-5374-6178" }, { "id": "Popa-R", "name": { "family": "Popa", "given": "Radu" } }, { "id": "Russell-M-J", "name": { "family": "Russell", "given": "Michael" } }, { "id": "Shen-Linhan", "name": { "family": "Shen", "given": "Linhan" }, "orcid": "0000-0003-3871-655X" }, { "id": "Sherwood-Lollar-B", "name": { "family": "Sherwood Lollar", "given": "Barbara" } }, { "id": "Staehle-R-L", "name": { "family": "Staehle", "given": "Robert" } }, { "id": "Stamenkovi\u0107-V", "name": { "family": "Stamenkovi\u0107", "given": "Vlada" }, "orcid": "0000-0003-2416-3683" }, { "id": "Stolper-D-A", "name": { "family": "Stolper", "given": "Daniel" }, "orcid": "0000-0003-3299-3177" }, { "id": "Templeton-A", "name": { "family": "Templeton", "given": "Alexis" } }, { "id": "Vandaele-A-C", "name": { "family": "Vandaele", "given": "Ann C." } }, { "id": "Viscardy-S", "name": { "family": "Viscardy", "given": "S\u00e9bastien" } }, { "id": "Webster-C-R", "name": { "family": "Webster", "given": "Christopher R." } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Wong-Michael-L", "name": { "family": "Wong", "given": "Michael L." } }, { "id": "Worden-J-R", "name": { "family": "Worden", "given": "John" }, "orcid": "0000-0003-0257-9549" } ] }, "title": "Methane on Mars and Habitability: Challenges and Responses", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2018 Yuk L. Yung et al., Published by Mary Ann Liebert, Inc. This Open Access article is distributed under the terms of the Creative Commons License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly credited. \n\nPublished Online: 19 Sep 2018. \n\nWe dedicate this article to JPL scientist Mark Allen, whose spirit of generosity inspired many of the conversations and much of the work that brought us together. This work was initiated and supported by the W.M. Keck Institute for Space Studies. We thank the Director of the Keck Institute for Space Studies, Tom Prince, the Executive Director, Michele Judd, and the capable and dedicated KISS staff for hosting and supporting the workshops that led to this article. We thank Charles Carter for the cover illustration and Meg Rosenberg for her work on editing and formatting. We thank Danica Adams, Siteng Fan, Amanda Gao, Mimi Gerstell, Yancheng Luo, Aimee Oz, Andrew Sappey, Sindhoora Tallapragada, and Kyle Weng for their efforts in editing the article. We thank Daniel Stolper for his participation and input in the workshop. The research was partly carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration. \n\nNo competing financial interests exist.\n\nPublished - ast-2018-1917.pdf
", "abstract": "Recent measurements of methane (CH_4) by the Mars Science Laboratory (MSL) now confront us with robust data that demand interpretation. Thus far, the MSL data have revealed a baseline level of CH_4 (\u223c0.4 parts per billion by volume [ppbv]), with seasonal variations, as well as greatly enhanced spikes of CH_4 with peak abundances of \u223c7\u2009ppbv. What do these CH_4 revelations with drastically different abundances and temporal signatures represent in terms of interior geochemical processes, or is martian CH_4 a biosignature? Discerning how CH_4 generation occurs on Mars may shed light on the potential habitability of Mars. There is no evidence of life on the surface of Mars today, but microbes might reside beneath the surface. In this case, the carbon flux represented by CH_4 would serve as a link between a putative subterranean biosphere on Mars and what we can measure above the surface. Alternatively, CH_4 records modern geochemical activity. Here we ask the fundamental question: how active is Mars, geochemically and/or biologically? In this article, we examine geological, geochemical, and biogeochemical processes related to our overarching question. The martian atmosphere and surface are an overwhelmingly oxidizing environment, and life requires pairing of electron donors and electron acceptors, that is, redox gradients, as an essential source of energy. Therefore, a fundamental and critical question regarding the possibility of life on Mars is, \"Where can we find redox gradients as energy sources for life on Mars?\" Hence, regardless of the pathway that generates CH_4 on Mars, the presence of CH_4, a reduced species in an oxidant-rich environment, suggests the possibility of redox gradients supporting life and habitability on Mars. Recent missions such as ExoMars Trace Gas Orbiter may provide mapping of the global distribution of CH_4. To discriminate between abiotic and biotic sources of CH_4 on Mars, future studies should use a series of diagnostic geochemical analyses, preferably performed below the ground or at the ground/atmosphere interface, including measurements of CH_4 isotopes, methane/ethane ratios, H_2 gas concentration, and species such as acetic acid. Advances in the fields of Mars exploration and instrumentation will be driven, augmented, and supported by an improved understanding of atmospheric chemistry and dynamics, deep subsurface biogeochemistry, astrobiology, planetary geology, and geophysics. Future Mars exploration programs will have to expand the integration of complementary areas of expertise to generate synergistic and innovative ideas to realize breakthroughs in advancing our understanding of the potential of life and habitable conditions having existed on Mars. In this spirit, we conducted a set of interdisciplinary workshops. From this series has emerged a vision of technological, theoretical, and methodological innovations to explore the martian subsurface and to enhance spatial tracking of key volatiles, such as CH_4.", "date": "2018-10", "date_type": "published", "publication": "Astrobiology", "volume": "18", "number": "10", "publisher": "Mary Ann Liebert", "pagerange": "1221-1242", "id_number": "CaltechAUTHORS:20180925-073151228", "issn": "1557-8070", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180925-073151228", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Keck Institute for Space Studies (KISS)" }, { "agency": "NASA/JPL/Caltech" } ] }, "local_group": { "items": [ { "id": "Keck-Institute-for-Space-Studies" }, { "id": "Astronomy-Department" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1089/ast.2018.1917", "pmcid": "PMC6205098", "primary_object": { "basename": "ast-2018-1917.pdf", "url": "https://authors.library.caltech.edu/records/6d6dk-78554/files/ast-2018-1917.pdf" }, "resource_type": "article", "pub_year": "2018", "author_list": "Yung, Yuk L.; Chen, Pin; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/3khxw-4bz36", "eprint_id": 92022, "eprint_status": "archive", "datestamp": "2023-08-22 00:08:00", "lastmod": "2023-10-19 23:54:36", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Kopparla-P", "name": { "family": "Kopparla", "given": "Pushkar" }, "orcid": "0000-0002-8951-3907" }, { "id": "Natraj-V", "name": { "family": "Natraj", "given": "Vijay" }, "orcid": "0000-0003-3154-9429" }, { "id": "Crisp-D", "name": { "family": "Crisp", "given": "David" }, "orcid": "0000-0002-4573-9998" }, { "id": "Bott-K", "name": { "family": "Bott", "given": "Kimberly" } }, { "id": "Swain-M-R", "name": { "family": "Swain", "given": "Mark R." }, "orcid": "0000-0002-0919-4468" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Observing Oceans in Tightly Packed Planetary Systems: Perspectives from Polarization Modeling of the TRAPPIST-1 System", "ispublished": "pub", "full_text_status": "public", "keywords": "planetary systems; planets and satellites: oceans; polarization", "note": "\u00a9 2018. The American Astronomical Society. \n\nReceived 2018 February 21; revised 2018 August 8; accepted 2018 August 8; published 2018 September 10. \n\nWe thank Peter Gao for insightful comments and Sloane Wiktorowicz for giving us an observer's perspective on the model results. We also want to thank the anonymous reviewer for their extraordinary commitment to helping us improve this paper. This research was supported in part by an NAI Virtual Planetary Laboratory grant from the University of Washington to the Jet Propulsion Laboratory (JPL) and California Institute of Technology (CIT), and in part by JPL. P.K., M.R.S., and Y.L.Y. acknowledge support from the President's and Director's Fund of CIT and JPL. We acknowledge use of the Exoplanet Orbit Database and the Exoplanet Data Explorer at exoplanets.org. We thank Jeremy Bailey, Lucyna Chudczer, and Kim Bott for helping discover a bug in our model code.\n\nPublished - Kopparla_2018_AJ_156_143.pdf
", "abstract": "The recently discovered TRAPPIST-1 system is exciting due to the possibility of several rocky, Earth-sized planets harboring liquid water on their surface. To assess the detectability of oceans on these planets, we model the disk-integrated phase curves and polarization signals for planets in this system for reflected starlight. We examine four cases: (1) dry planet, (2) cloud-covered planet, (3) planet with regional-scale oceans, and (4) planet with global oceans. Polarization signals are strongest for optically thin (\u227e 0.1) atmospheres over widespread oceans, with the degree of polarization being up to 90% for a single planet or on the order of 100 parts per billion for the star\u2013planet system. In cases where reflected light from different planets in a tightly packed system cannot be separated, observing in polarized light allows for up to a tenfold increase in star\u2013planet contrast compared to photometric observations alone. However, polarization from other sources, such as atmospheric scattering and cloud variability, will pose major challenges to the detection of glint (specularly reflected starlight) polarization signals. Planned telescopes like LUVOIR may be capable of observing glint from Earth-like planets around Sun-like stars, and if equipped with a polarimeter can significantly improve our ability to detect and study oceans on rocky exoplanets.", "date": "2018-10", "date_type": "published", "publication": "Astronomical Journal", "volume": "156", "number": "4", "publisher": "American Astronomical Society", "pagerange": "Art. No. 143", "id_number": "CaltechAUTHORS:20190102-155140312", "issn": "1538-3881", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190102-155140312", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "University of Washington" }, { "agency": "JPL President and Director's Fund" } ] }, "local_group": { "items": [ { "id": "Astronomy-Department" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.3847/1538-3881/aad9a1", "primary_object": { "basename": "Kopparla_2018_AJ_156_143.pdf", "url": "https://authors.library.caltech.edu/records/3khxw-4bz36/files/Kopparla_2018_AJ_156_143.pdf" }, "resource_type": "article", "pub_year": "2018", "author_list": "Kopparla, Pushkar; Natraj, Vijay; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/k6k18-tzd28", "eprint_id": 87307, "eprint_status": "archive", "datestamp": "2023-08-21 23:53:20", "lastmod": "2023-10-18 21:02:32", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Li-Cheng", "name": { "family": "Li", "given": "Cheng" }, "orcid": "0000-0002-8280-3119" }, { "id": "Le-Tianhao", "name": { "family": "Le", "given": "Tianhao" } }, { "id": "Zhang-Xi", "name": { "family": "Zhang", "given": "Xi" } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "A High-performance Atmospheric Radiation Package: with applications to the radiative energy budgets of giant planets", "ispublished": "pub", "full_text_status": "public", "keywords": "HARP; Radiative transfer model; Giant planet; Ice giants; Energy budget", "note": "\u00a9 2018 Elsevier Ltd. \n\nReceived 28 January 2018, Revised 2 June 2018, Accepted 3 June 2018, Available online 6 June 2018. \n\nWe thank Julie Moses for kindly providing the photochemical model results of four giant planets. X.Z. acknowledges support from NASA Solar System Workings grant NNX16AG08G. C.L. acknowledges the support from NASA Postdoc Program Fellowship. \n\nCode availability: HARP is an open-source program and will be made freely available to the community on Github at https://github.com/luminoctum/athena-harp.\n\nSubmitted - 1806.02573.pdf
", "abstract": "A High-performance Atmospheric Radiation Package (HARP) is developed for studying multiple-scattering planetary atmospheres. HARP is an open-source program written in C++ that utilizes high-level data structure and parallel-computing algorithms. It is generic in three aspects. First, the construction of the model atmospheric profile is generic. The program can either take in an atmospheric profile or construct an adiabatic thermal and compositional profile, taking into account the clouds and latent heat release due to condensation. Second, the calculation of opacity is generic, based on line-by-line molecular transitions and tabulated continuum data, along with a table of correlated-k opacity provided as an option to speed up the calculation of energy fluxes. Third, the selection of the solver for the radiative transfer equation is generic. The solver is not hardwired in the program. Instead, based on the purpose, a variety of radiative transfer solvers can be chosen to couple with the atmosphere model and the opacity model.\nWe use the program to investigate the radiative heating and cooling rates of all four giant planets in the Solar System. Our Jupiter's result is consistent with previous publications. Saturn has nearly perfect balance between the heating rate and cooling rate. Uranus has the least radiative fluxes because of the lack of CH_4 and its photochemical products. Both Uranus and Neptune suffer from a severe energy deficit in their stratospheres. Possible ways to resolve this issue are discussed. Finally, we recalculate the radiative time constants of all four giant planet atmospheres and find that the traditional values from (Conrath BJ, Gierasch PJ, Leroy SS. Temperature and Circulation in the Stratosphere of the Outer Planets. Icar. 1990;83:255-81) are significantly overestimated.", "date": "2018-09", "date_type": "published", "publication": "Journal of Quantitative Spectroscopy and Radiative Transfer", "volume": "217", "publisher": "Elsevier", "pagerange": "353-362", "id_number": "CaltechAUTHORS:20180622-081434127", "issn": "0022-4073", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180622-081434127", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NNX16AG08G" }, { "agency": "NASA Postdoctoral Program" } ] }, "local_group": { "items": [ { "id": "Astronomy-Department" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/j.jqsrt.2018.06.002", "primary_object": { "basename": "1806.02573.pdf", "url": "https://authors.library.caltech.edu/records/k6k18-tzd28/files/1806.02573.pdf" }, "resource_type": "article", "pub_year": "2018", "author_list": "Li, Cheng; Le, Tianhao; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/54npt-ftd13", "eprint_id": 90786, "eprint_status": "archive", "datestamp": "2023-08-21 23:37:47", "lastmod": "2023-10-19 14:52:46", "type": "book_section", "metadata_visibility": "show", "creators": { "items": [ { "id": "Natraj-V", "name": { "family": "Natraj", "given": "Vijay" }, "orcid": "0000-0003-3154-9429" }, { "id": "Jiang-Jonathan-H", "name": { "family": "Jiang", "given": "Jonathan H." }, "orcid": "0000-0002-5929-8951" }, { "id": "Kopparla-P", "name": { "family": "Kopparla", "given": "Pushkar" }, "orcid": "0000-0002-8951-3907" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Doicu-A", "name": { "family": "Doicu", "given": "Adrian" } }, { "id": "Loyola-D", "name": { "family": "Loyola", "given": "Diego" } } ] }, "title": "Aerosol Retrievals from DSCOVR Measurements", "ispublished": "unpub", "full_text_status": "restricted", "keywords": "aerosol; vertical profile; retrievals; EPIC", "note": "\u00a9 2018 IEEE. \n\nPart of this work was performed at the Jet Propulsion Laboratory, California Institute of Technology. This work was funded by the NASA Earth Science U.S. Participating Investigator program.", "abstract": "Atmospheric aerosols play a central role in the Earth's radiative budget. Together with various greenhouse gases, aerosols represent the most significant anthropogenic forcing responsible for climate change. However, uncertainties about the origin and composition of aerosol particles, their size distribution, concentration, spatial and temporal variability, make climate change prediction challenging. In order to quantify the influence of aerosols on the Earth's climate and to better validate climate models, information about their global abundance, properties and height distribution are needed. We use measurements of the Oxygen A and B bands from the Earth Polychromatic Imaging Camera (EPIC) onboard the Deep Space Climate Observatory (DSCOVR) to retrieve aerosol parameters such as optical depth, height and effective radius. Aerosol retrievals are ill-posed because of the large spatial and temporal variability in their composition and vertical distribution. We compare several retrieval methods and determine the optimum technique for the retrieval algorithm.", "date": "2018-07", "date_type": "published", "publisher": "IEEE", "place_of_pub": "Piscataway, NJ", "pagerange": "6026-6028", "id_number": "CaltechAUTHORS:20181109-084430672", "isbn": "978-1-5386-7150-4", "book_title": "2018 IEEE International Geoscience and Remote Sensing Symposium (IGARSS 2018)", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20181109-084430672", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA/JPL/Caltech" } ] }, "local_group": { "items": [ { "id": "Astronomy-Department" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1109/IGARSS.2018.8519014", "resource_type": "book_section", "pub_year": "2018", "author_list": "Natraj, Vijay; Jiang, Jonathan H.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/bq7tf-n8q52", "eprint_id": 92026, "eprint_status": "archive", "datestamp": "2023-08-19 10:06:49", "lastmod": "2023-10-19 23:54:40", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Jiang-Jonathan-H", "name": { "family": "Jiang", "given": "Jonathan H." }, "orcid": "0000-0002-5929-8951" }, { "id": "Zhai-Albert-J", "name": { "family": "Zhai", "given": "Albert J." } }, { "id": "Herman-J-R", "name": { "family": "Herman", "given": "Jay" }, "orcid": "0000-0002-9146-1632" }, { "id": "Zhai-Chengxing", "name": { "family": "Zhai", "given": "Chengxing" }, "orcid": "0000-0002-0291-4522" }, { "id": "Hu-Renyu", "name": { "family": "Hu", "given": "Renyu" }, "orcid": "0000-0003-2215-8485" }, { "id": "Su-Hui", "name": { "family": "Su", "given": "Hui" }, "orcid": "0000-0003-1265-9702" }, { "id": "Natraj-V", "name": { "family": "Natraj", "given": "Vijay" }, "orcid": "0000-0003-3154-9429" }, { "id": "Li-Jiazheng", "name": { "family": "Li", "given": "Jiazheng" } }, { "id": "Xu-Feng", "name": { "family": "Xu", "given": "Feng" }, "orcid": "0000-0001-5155-9478" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Using Deep Space Climate Observatory Measurements to Study the Earth as an Exoplanet", "ispublished": "pub", "full_text_status": "public", "keywords": "Earth", "note": "\u00a9 2018. The American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 3.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. \n\nReceived 2018 April 2; revised 2018 May 9; accepted 2018 May 12; published 2018 June 27. \n\nThis work was partially support by the Exoplanet Science Initiative (ESI) at the Jet Propulsion Laboratory (JPL), California Institute of Technology (Caltech), under contract with NASA. We acknowledge the DSCOVR project science team for support. We thank Nicolas Cowan of McGill University for detailed and constructive comments. Anthony Davis and Gerard van Harten of JPL, Stuart Bartlett of Caltech, Sara Seager of the Massachusetts Institute of Technology, and Adam Showman of the University of Arizona also provided useful comments on the data calibration, analysis methodology, and exoplanet imaging techniques. \n\nData and code availability: The DSCOVR data used for this study can be downloaded at https://eosweb.larc.nasa.gov/project/dscovr/dscovr_epic_l1a_2. The computer code used during the study is available on request from the authors.\n\nPublished - Jiang_2018_AJ_156_26.pdf
Accepted Version - 1805.05834.pdf
", "abstract": "Even though it was not designed as an exoplanetary research mission, the Deep Space Climate Observatory (DSCOVR) has been opportunistically used for a novel experiment in which Earth serves as a proxy exoplanet. More than 2 yr of DSCOVR Earth images were employed to produce time series of multiwavelength, single-point light sources in order to extract information on planetary rotation, cloud patterns, surface type, and orbit around the Sun. In what follows, we assume that these properties of the Earth are unknown and instead attempt to derive them from first principles. These conclusions are then compared with known data about our planet. We also used the DSCOVR data to simulate phase-angle changes, as well as the minimum data collection rate needed to determine the rotation period of an exoplanet. This innovative method of using the time evolution of a multiwavelength, reflected single-point light source can be deployed for retrieving a range of intrinsic properties of an exoplanet around a distant star.", "date": "2018-07", "date_type": "published", "publication": "Astronomical Journal", "volume": "156", "number": "1", "publisher": "American Astronomical Society", "pagerange": "Art. No. 26", "id_number": "CaltechAUTHORS:20190102-155140742", "issn": "1538-3881", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190102-155140742", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA/JPL/Caltech" } ] }, "local_group": { "items": [ { "id": "Astronomy-Department" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.3847/1538-3881/aac6e2", "primary_object": { "basename": "1805.05834.pdf", "url": "https://authors.library.caltech.edu/records/bq7tf-n8q52/files/1805.05834.pdf" }, "related_objects": [ { "basename": "Jiang_2018_AJ_156_26.pdf", "url": "https://authors.library.caltech.edu/records/bq7tf-n8q52/files/Jiang_2018_AJ_156_26.pdf" } ], "resource_type": "article", "pub_year": "2018", "author_list": "Jiang, Jonathan H.; Zhai, Albert J.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/s327b-mzg80", "eprint_id": 91260, "eprint_status": "archive", "datestamp": "2023-08-21 23:32:32", "lastmod": "2023-10-19 22:21:00", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Aumann-Hartmut-H", "name": { "family": "Aumann", "given": "Hartmut H." }, "orcid": "0000-0002-4311-7546" }, { "id": "Chen-Xiuhong", "name": { "family": "Chen", "given": "Xiuhong" } }, { "id": "Fishbein-Evan", "name": { "family": "Fishbein", "given": "Evan" } }, { "id": "Geer-Alan", "name": { "family": "Geer", "given": "Alan" } }, { "id": "Havemann-Stephan", "name": { "family": "Havemann", "given": "Stephan" }, "orcid": "0000-0002-3259-091X" }, { "id": "Huang-Xianglei", "name": { "family": "Huang", "given": "Xianglei" }, "orcid": "0000-0002-7129-614X" }, { "id": "Liu-Xu", "name": { "family": "Liu", "given": "Xu" }, "orcid": "0000-0002-0473-3143" }, { "id": "Liuzzi-Giuliano", "name": { "family": "Liuzzi", "given": "Giuliano" }, "orcid": "0000-0003-3638-5750" }, { "id": "DeSouza-Machado-Sergio", "name": { "family": "DeSouza-Machado", "given": "Sergio" } }, { "id": "Manning-Evan-M", "name": { "family": "Manning", "given": "Evan M." } }, { "id": "Masiello-Guido", "name": { "family": "Masiello", "given": "Guido" }, "orcid": "0000-0002-7986-8296" }, { "id": "Matricardi-Marco", "name": { "family": "Matricardi", "given": "Marco" }, "orcid": "0000-0001-7514-9473" }, { "id": "Moradi-Isaac", "name": { "family": "Moradi", "given": "Isaac" }, "orcid": "0000-0003-2194-1427" }, { "id": "Natraj-Vijay", "name": { "family": "Natraj", "given": "Vijay" }, "orcid": "0000-0003-3154-9429" }, { "id": "Serio-Carmine", "name": { "family": "Serio", "given": "Carmine" }, "orcid": "0000-0002-5931-7681" }, { "id": "Strow-Larrabee", "name": { "family": "Strow", "given": "Larrabee" }, "orcid": "0000-0001-5999-3519" }, { "id": "Vidot-Jerome", "name": { "family": "Vidot", "given": "Jerome" } }, { "id": "Wuilson-R-Chris", "name": { "family": "Wilson", "given": "R. Chris" } }, { "id": "Wu-Wan", "name": { "family": "Wu", "given": "Wan" } }, { "id": "Yang-Qiguang", "name": { "family": "Yang", "given": "Qiguang" } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Evaluation of Radiative Transfer Models With Clouds", "ispublished": "pub", "full_text_status": "public", "keywords": "infrared; hyperspectral; cloud; radiative transfer; weather forecasting; climate", "note": "\u00a9 2018. American Geophysical Union. \n\nReceived 14 NOV 2017. Accepted 4 APR 2018. Accepted article online 16 APR 2018. Published online 13 JUN 2018. \n\nThe work described in this paper was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration. Work at JPL and UMBC was funded by NASA ROSES, with the longtime support of Ramesh Kakar of NASA Headquarters. Steve Broberg helped with technical editing. The work at LARC was supported by NASA NAST\u2010I and CLARREO projects. The work at NASA/GMAO was funded under NASA grant NNX17AE79A Goddard Space Flight Center Cooperative Agreement. The work at the University of Michigan was supported by NASA grant NNX15AC25G. The work at Meteo France was supported by the EUMETSAT NWP\u2010SAF program. The work at the UK Met Office was supported as part of the science program theme \"Improved use of Satellite Data\". The 7,377 atmospheric states and associated AIRS spectra used for this paper can be found at ftp://thunder.jpl.nasa.gov/hha/Cloudy_RTA. The file readme.20160518.txt defines various parameters. The file AIRS_SRF_m140f.mat defines the AIRS SRF for each of the 2,378 channels in a MATLAB Version 7.0 format.\n\nPublished - Aumann_et_al-2018-Journal_of_Geophysical_Research_3A_Atmospheres.pdf
", "abstract": "Data from hyperspectral infrared sounders are routinely ingested worldwide by the National Weather Centers. The cloud\u2010free fraction of this data is used for initializing forecasts which include temperature, water vapor, water cloud, and ice cloud profiles on a global grid. Although the data from these sounders are sensitive to the vertical distribution of ice and liquid water in clouds, this information is not fully utilized. In the future, this information could be used for validating clouds in National Weather Center models and for initializing forecasts. We evaluate how well the calculated radiances from hyperspectral Radiative Transfer Models (RTMs) compare to cloudy radiances observed by AIRS and to one another. Vertical profiles of the clouds, temperature, and water vapor from the European Center for Medium\u2010Range Weather Forecasting were used as input for the RTMs. For nonfrozen ocean day and night data, the histograms derived from the calculations by several RTMs at 900 cm^(\u22121) have a better than 0.95 correlation with the histogram derived from the AIRS observations, with a bias relative to AIRS of typically less than 2 K. Differences in the cloud physics and cloud overlap assumptions result in little bias between the RTMs, but the standard deviation of the differences ranges from 6 to 12 K. Results at 2,616 cm^(\u22121) at night are reasonably consistent with results at 900 cm^(\u22121). Except for RTMs which use full scattering calculations, the bias and histogram correlations at 2,616 cm^(\u22121) are inferior to those at 900 cm^(\u22121) for daytime calculations.", "date": "2018-06-16", "date_type": "published", "publication": "Journal of Geophysical Research. Atmospheres", "volume": "123", "number": "11", "publisher": "American Geophysical Union", "pagerange": "6142-6157", "id_number": "CaltechAUTHORS:20181127-160003740", "issn": "2169-897X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20181127-160003740", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA/JPL/Caltech" }, { "agency": "NASA", "grant_number": "NNX17AE79A" }, { "agency": "NASA", "grant_number": "NNX15AC25G" }, { "agency": "EUMETSAT NWP\u2010SAF" }, { "agency": "Meteorological Office (UK)" } ] }, "local_group": { "items": [ { "id": "Astronomy-Department" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2017jd028063", "primary_object": { "basename": "Aumann_et_al-2018-Journal_of_Geophysical_Research_3A_Atmospheres.pdf", "url": "https://authors.library.caltech.edu/records/s327b-mzg80/files/Aumann_et_al-2018-Journal_of_Geophysical_Research_3A_Atmospheres.pdf" }, "resource_type": "article", "pub_year": "2018", "author_list": "Aumann, Hartmut H.; Chen, Xiuhong; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/2y9f4-pbj86", "eprint_id": 103561, "eprint_status": "archive", "datestamp": "2023-08-19 09:42:06", "lastmod": "2023-10-20 16:29:45", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Tian-Pengfei", "name": { "family": "Tian", "given": "Pengfei" } }, { "id": "Zhang-Lei", "name": { "family": "Zhang", "given": "Lei" }, "orcid": "0000-0001-9031-4318" }, { "id": "Ma-Jianmin", "name": { "family": "Ma", "given": "Jianmin" } }, { "id": "Tang-Kai", "name": { "family": "Tang", "given": "Kai" }, "orcid": "0000-0002-5402-0344" }, { "id": "Xu-Lili", "name": { "family": "Xu", "given": "Lili" } }, { "id": "Wang-Yuan", "name": { "family": "Wang", "given": "Yuan" }, "orcid": "0000-0001-6657-8401" }, { "id": "Cao-Xianjie", "name": { "family": "Cao", "given": "Xianjie" } }, { "id": "Liang-Jiening", "name": { "family": "Liang", "given": "Jiening" } }, { "id": "Ji-Yuemeng", "name": { "family": "Ji", "given": "Yuemeng" }, "orcid": "0000-0002-8641-4276" }, { "id": "Jiang-Jonathan-H", "name": { "family": "Jiang", "given": "Jonathan H." }, "orcid": "0000-0002-5929-8951" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Zhang-Renyi", "name": { "family": "Zhang", "given": "Renyi" }, "orcid": "0000-0001-8708-3862" } ] }, "title": "Radiative absorption enhancement of dust mixed with anthropogenic pollution over East Asia", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 Author(s) 2018. This work is distributed under the Creative Commons Attribution 4.0 License. \n\nReceived: 05 Jan 2018 \u2013 Discussion started: 30 Jan 2018 \u2013 Revised: 16 May 2018 \u2013 Accepted: 17 May 2018 \u2013 Published: 04 Jun 2018. \n\nSpecial issue | Regional transport and transformation of air pollution in eastern China. Editor(s): T. Zhu, Y. Zhang, J. Chen, D. E. Heard, Z. Li, L. T. Molina, L. Morawska, D. Parrish, H. Su, R. Zhang, and Y. Wang. \n\nThis research was financially supported by National Natural Science Foundation of China (41627807 and 41475008) and National Key R&D Program of China (2016YFC0401003). Pengfei Tian was funded by China Postdoctoral Science Foundation (2018M631216). Yuan Wang acknowledged the support from NASA ROSES ACMAP. Yuemeng Ji was financially supported by National Natural Science Foundation of China (41675122) and Science and Technology Program of Guangzhou city (201707010188). The authors thank the principal investigators and staff for establishing and maintaining the AERONET sites used in this research. We thank the Institute for Computational Earth System Science (ICESS), University of California, for providing the SADART model. Yuan Wang, Jonathan H. Jiang, and Yuk L. Yung acknowledge support by the Jet Propulsion Laboratory, California Institute of Technology, under contract with NASA. \n\nData Availability. The original sun photometer data are available from the AERONET website (https://aeronet.gsfc.nasa.gov/cgi-bin/webtool_opera_v2_inv, last access: 31 May 2018; Holben et al., 1998). The radiative flux data for the worldwide AERONET sites calculated using the SBDART model and all data for the figures and table in this research are available from the authors upon request. \n\nThe supplement related to this article is available online at: https://doi.org/10.5194/acp-18-7815-2018-supplement. \n\nThe authors declare that they have no conflict of interest. \n\nEdited by: Zhanqing Li. Reviewed by: three anonymous referees.\n\nPublished - acp-18-7815-2018.pdf
Supplemental Material - acp-18-7815-2018-supplement.pdf
", "abstract": "The particle mixing state plays a significant yet poorly quantified role in aerosol radiative forcing, especially for the mixing of dust (mineral absorbing) and anthropogenic pollution (black carbon absorbing) over East Asia. We have investigated the absorption enhancement of mixed-type aerosols over East Asia by using the Aerosol Robotic Network observations and radiative transfer model calculations. The mixed-type aerosols exhibit significantly enhanced absorbing ability than the corresponding unmixed dust and anthropogenic aerosols, as revealed in the spectral behavior of absorbing aerosol optical depth, single scattering albedo, and imaginary refractive index. The aerosol radiative efficiencies for the dust, mixed-type, and anthropogenic aerosols are \u2212101.0, \u2212112.9, and \u221298.3\u2009Wm\u207b\u00b2\u03c4\u207b\u00b9 at the bottom of the atmosphere (BOA); \u221242.3, \u221222.5, and \u221239.8\u2009Wm\u207b\u00b2\u03c4\u207b\u00b9 at the top of the atmosphere (TOA); and 58.7, 90.3, and 58.5\u2009Wm\u207b\u00b2\u03c4\u207b\u00b9 in the atmosphere (ATM), respectively. The BOA cooling and ATM heating efficiencies of the mixed-type aerosols are significantly higher than those of the unmixed aerosol types over the East Asia region, resulting in atmospheric stabilization. In addition, the mixed-type aerosols correspond to a lower TOA cooling efficiency, indicating that the cooling effect by the corresponding individual aerosol components is partially counteracted. We conclude that the interaction between dust and anthropogenic pollution not only represents a viable aerosol formation pathway but also results in unfavorable dispersion conditions, both exacerbating the regional air pollution in East Asia. Our results highlight the necessity to accurately account for the mixing state of aerosols in atmospheric models over East Asia in order to better understand the formation mechanism for regional air pollution and to assess its impacts on human health, weather, and climate.", "date": "2018-06-04", "date_type": "published", "publication": "Atmospheric Chemistry and Physics", "volume": "18", "number": "11", "publisher": "European Geosciences Union", "pagerange": "7815-7825", "id_number": "CaltechAUTHORS:20200529-093434091", "issn": "1680-7324", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200529-093434091", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "National Natural Science Foundation of China", "grant_number": "41627807" }, { "agency": "National Natural Science Foundation of China", "grant_number": "41475008" }, { "agency": "National Key Research and Development Program of China", "grant_number": "2016YFC0401003" }, { "agency": "China Postdoctoral Science Foundation", "grant_number": "2018M631216" }, { "agency": "National Natural Science Foundation of China", "grant_number": "41675122" }, { "agency": "Guangzhou City", "grant_number": "201707010188" }, { "agency": "NASA/JPL/Caltech" } ] }, "local_group": { "items": [ { "id": "Astronomy-Department" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/acp-18-7815-2018", "primary_object": { "basename": "acp-18-7815-2018-supplement.pdf", "url": "https://authors.library.caltech.edu/records/2y9f4-pbj86/files/acp-18-7815-2018-supplement.pdf" }, "related_objects": [ { "basename": "acp-18-7815-2018.pdf", "url": "https://authors.library.caltech.edu/records/2y9f4-pbj86/files/acp-18-7815-2018.pdf" } ], "resource_type": "article", "pub_year": "2018", "author_list": "Tian, Pengfei; Zhang, Lei; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/xxg7k-8yt67", "eprint_id": 91259, "eprint_status": "archive", "datestamp": "2023-08-21 23:01:27", "lastmod": "2023-10-19 22:20:56", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Shi-Xiaoqin", "name": { "family": "Shi", "given": "Xiaoqin" } }, { "id": "Zhao-Chuanfeng", "name": { "family": "Zhao", "given": "Chuanfeng" }, "orcid": "0000-0002-5196-3996" }, { "id": "Jiang-Jonathan-H", "name": { "family": "Jiang", "given": "Jonathan H." }, "orcid": "0000-0002-5929-8951" }, { "id": "Wang-Chunying", "name": { "family": "Wang", "given": "Chunying" } }, { "id": "Yang-Xin", "name": { "family": "Yang", "given": "Xin" }, "orcid": "0000-0001-5111-2959" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Spatial Representativeness of PM_(2.5) Concentrations Obtained Using Observations From Network Stations", "ispublished": "pub", "full_text_status": "public", "keywords": "representative area; PM_(2.5); spatial variation; network observation", "note": "\u00a9 2018. American Geophysical Union. \n\nReceived 18 OCT 2017. Accepted 27 FEB 2018. Accepted article online 5 MAR 2018. Published online 25 MAR 2018. \n\nThis work was supported by the Ministry of Science and Technology of China (grants 2017YFC1501403, 2013CB955802, and 2012AA120901), the National Natural Science Foundation of China (grant 41575143), the China \"1000 plan\" young scholar program, the State Key Laboratory of Earth Surface Processes and Resource Ecology (2017\u2010ZY\u201002), and the Fundamental Research Funds for the Central Universities (2017EYT18 and 312231103). The authors also acknowledge the support by the Jet Propulsion Laboratory, California Institute of Technology, sponsored by NASA. The data used in this study are available by request to Chuanfeng Zhao through czhao@bnu.edu.cn or downloaded directly from ftp: nwpc.nmc.cn (user: pub, pswd: verygood) under directory zhao_paper_data.\n\nPublished - Shi_et_al-2018-Journal_of_Geophysical_Research_3A_Atmospheres.pdf
", "abstract": "Haze has been a focused air pollution phenomenon in China, and its characterization is highly desired. Aerosol properties obtained from a single station are frequently used to represent the haze condition over a large domain, such as tens of kilometers, which could result in high uncertainties due to their spatial variation. Using a high\u2010resolution network observation over an urban city in North China from November 2015 to February 2016, this study examines the spatial representativeness of ground station observations of particulate matter with diameters less than 2.5 \u03bcm (PM_(2.5)). We developed a new method to determine the representative area of PM_(2.5) measurements from limited stations. The key idea is to determine the PM_(2.5) spatial representative area using its spatial variability and temporal correlation. We also determine stations with large representative area using two grid networks with different resolutions. Based on the high spatial resolution measurements, the representative area of PM_(2.5) at one station can be determined from the grids with high correlations and small differences of PM_(2.5). The representative area for a single station in the study period ranges from 0.25 to 16.25 km^2 but is less than 3 km^2 for more than half of the stations. The representative area varies with locations, and observation at 10 optimal stations would have a good representativeness of those obtained from 169 stations for the 4 month time scale studied. Both evaluations with an empirical orthogonal function analysis and with independent data set corroborate the validity of the results found in this study.", "date": "2018-03-27", "date_type": "published", "publication": "Journal of Geophysical Research. Atmospheres", "volume": "123", "number": "6", "publisher": "American Geophysical Union", "pagerange": "3145-3158", "id_number": "CaltechAUTHORS:20181127-160003622", "issn": "2169-897X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20181127-160003622", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Ministry of Science and Technology (China)", "grant_number": "2017YFC1501403" }, { "agency": "Ministry of Science and Technology (China)", "grant_number": "2013CB955802" }, { "agency": "Ministry of Science and Technology (China)", "grant_number": "2012AA120901" }, { "agency": "National Natural Science Foundation of China", "grant_number": "41575143" }, { "agency": "State Key Laboratory of Earth Surface Processes and Resource Ecology", "grant_number": "2017-ZY-02" }, { "agency": "China 1000-Young Talents Plan" }, { "agency": "Fundamental Research Funds for the Central Universities", "grant_number": "2017EYT18" }, { "agency": "Fundamental Research Funds for the Central Universities", "grant_number": "312231103" }, { "agency": "NASA/JPL/Caltech" } ] }, "local_group": { "items": [ { "id": "Astronomy-Department" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1002/2017jd027913", "primary_object": { "basename": "Shi_et_al-2018-Journal_of_Geophysical_Research_3A_Atmospheres.pdf", "url": "https://authors.library.caltech.edu/records/xxg7k-8yt67/files/Shi_et_al-2018-Journal_of_Geophysical_Research_3A_Atmospheres.pdf" }, "resource_type": "article", "pub_year": "2018", "author_list": "Shi, Xiaoqin; Zhao, Chuanfeng; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/4y8fz-kma86", "eprint_id": 85130, "eprint_status": "archive", "datestamp": "2023-08-21 23:01:11", "lastmod": "2023-10-18 17:54:16", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Shi-Xiaoqin", "name": { "family": "Shi", "given": "Xiaoqin" } }, { "id": "Zhao-Chuanfeng", "name": { "family": "Zhao", "given": "Chuanfeng" }, "orcid": "0000-0002-5196-3996" }, { "id": "Jiang-Jonathan-H", "name": { "family": "Jiang", "given": "Jonathan H." }, "orcid": "0000-0002-5929-8951" }, { "id": "Wang-Chunying", "name": { "family": "Wang", "given": "Chunying" } }, { "id": "Yang-Xin", "name": { "family": "Yang", "given": "Xin" }, "orcid": "0000-0001-5111-2959" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Spatial Representativeness of PM_(2.5) Concentrations Obtained Using Reduced Number of Network Stations", "ispublished": "pub", "full_text_status": "public", "keywords": "Representation area; PM2.5; Spatial variation; Network observation", "note": "\u00a9 2018 American Geophysical Union. \n\nReceived 18 OCT 2017; Accepted 27 FEB 2018; Accepted article online 5 MAR 2018; Published online 25 MAR 2018. \n\nThis work was supported by the Ministry of Science and Technology of China (grant 2017YFC1501403, 2013CB955802, 2012AA120901), the National Natural Science Foundation of China (grant 41575143), the China \"1000 plan\" young scholar program, the State Key Laboratory of Earth Surface Processes and Resource Ecology (2017-ZY-02), the Fundamental Research Funds for the Central Universities (2017EYT18, 312231103). The authors also acknowledge the support by the Jet Propulsion Laboratory, California Institute of Technology, sponsored by NASA. The data used in this study are available by request to Chuanfeng Zhao through czhao@bnu.edu.cn, or downloaded directly from ftp: nwpc.nmc.cn (user: pub, pswd: verygood) under directory zhao_paper_data.\n\nPublished - Shi_et_al-2018-Journal_of_Geophysical_Research__Atmospheres.pdf
", "abstract": "Haze has been a focused air pollution phenomenon in China, and its characterization is highly desired. Aerosol properties obtained from a single station are frequently used to represent the haze condition over a large domain, such as tens of kilometers, which could result in high uncertainties due to their spatial variation. Using a high resolution network observation over an urban city in North China from November 2015 to February 2016, this study examines the spatial representativeness of ground station observations of particulate matter with diameters less than 2.5 \u03bcm (PM_(2.5)). We developed a new method to determine the representative area of PM_(2.5) measurements from limited stations. The key idea is to determine the PM_(2.5) spatial representative area using its spatial variability and temporal correlation. We also determine stations with large representative area using two grid networks with different resolutions. Based on the high spatial resolution measurements, the representative area of PM_(2.5) at one station can be determined from the grids with high correlations and small differences of PM_(2.5). The representative area for a single station in the study period ranges from 0.25 to 16.25 km^2, but is less than 3 km^2 for more than half of the stations. The representative area varies with locations, and observation at 10 optimal stations would have a good representativeness of those obtained from 169 stations for the four-month time scale studied. Both evaluations with an empirical orthogonal function (EOF) analysis and with independent dataset corroborate the validity of the results found in this study.", "date": "2018-03-27", "date_type": "published", "publication": "Journal of Geophysical Research. Atmospheres", "volume": "123", "number": "6", "publisher": "American Geophysical Union", "pagerange": "3145-3158", "id_number": "CaltechAUTHORS:20180306-092026843", "issn": "2169-897X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180306-092026843", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Ministry of Science and Technology (Taipei)", "grant_number": "2017YFC1501403" }, { "agency": "Ministry of Science and Technology (Taipei)", "grant_number": "2013CB955802" }, { "agency": "Ministry of Science and Technology (Taipei)", "grant_number": "2012AA120901" }, { "agency": "National Natural Science Foundation of China", "grant_number": "41575143" }, { "agency": "China \"1000 Plan\" Young Scholar Program" }, { "agency": "State Key Laboratory of Earth Surface Processes and Resource Ecology", "grant_number": "2017-ZY-02" }, { "agency": "Fundamental Research Funds for the Central Universities", "grant_number": "2017EYT18" }, { "agency": "Fundamental Research Funds for the Central Universities", "grant_number": "312231103" }, { "agency": "NASA/JPL/Caltech" } ] }, "local_group": { "items": [ { "id": "Astronomy-Department" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1002/2017JD027913", "primary_object": { "basename": "Shi_et_al-2018-Journal_of_Geophysical_Research__Atmospheres.pdf", "url": "https://authors.library.caltech.edu/records/4y8fz-kma86/files/Shi_et_al-2018-Journal_of_Geophysical_Research__Atmospheres.pdf" }, "resource_type": "article", "pub_year": "2018", "author_list": "Shi, Xiaoqin; Zhao, Chuanfeng; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/tykxn-jh954", "eprint_id": 84913, "eprint_status": "archive", "datestamp": "2023-08-21 22:51:22", "lastmod": "2023-10-18 16:57:58", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Ma-Zhanshan", "name": { "family": "Ma", "given": "Zhanshan" } }, { "id": "Liu-Qijun", "name": { "family": "Liu", "given": "Qijun" } }, { "id": "Zhao-Chuanfeng", "name": { "family": "Zhao", "given": "Chuanfeng" }, "orcid": "0000-0002-5196-3996" }, { "id": "Shen-Xueshun", "name": { "family": "Shen", "given": "Xueshun" } }, { "id": "Wang-Yuan", "name": { "family": "Wang", "given": "Yuan" }, "orcid": "0000-0001-6657-8401" }, { "id": "Jiang-Jonathan-H", "name": { "family": "Jiang", "given": "Jonathan H." }, "orcid": "0000-0002-5929-8951" }, { "id": "Li-Zhe", "name": { "family": "Li", "given": "Zhe" } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk" }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Application and Evaluation of an Explicit Prognostic Cloud Cover Scheme in GRAPES Global Forecast System", "ispublished": "pub", "full_text_status": "public", "keywords": "Cloud cover; prognostic cloud cover scheme; diagnostic cloud cover scheme; GRAPES_GFS; radiative flux", "note": "\u00a9 2017 American Geophysical Union. This is an open access article under the terms of the Creative Commons \nAttribution-NonCommercial-NoDerivs License, which permits use and distribution in any medium, provided the original work is properly cited, the use is non-commercial and no \nmodifications or adaptations are made. \n\nReceived 17 NOV 2017; Accepted 17 FEB 2018; Accepted article online 21 FEB 2018; Published online 8 MAR 2018. \n\nThis paper is jointly supported by the Ministry of Science and Technology of China (2017YFC1501403 and 2017YFC1501406), the National Natural Science Foundation of China (NSFC) (grants 41575143, 41105067, and 41375107), Special Fund for Meteorology Scientific Research in the Public Interest (grants GYHY201506018 and GYHY201406005), the State Key Laboratory of Earth Surface Processes and Resource Ecology (2017\u2010ZY\u201002), and the Fundamental Research Funds for the Central Universities. Coauthor Y.W. appreciates the funding support provided by US National Science Foundation (NSF, award 1700727). Coauthor J.H.J. acknowledges the support by the Jet Propulsion Laboratory, California Institute of Technology, sponsored by NASA. The data used in this study can be downloaded via ftp: nwpc.nmc.cn (user: pub, pswd: verygood) and are also available by request to Zhanshan Ma through mazs@cma.gov.cn.\n\nPublished - Ma_et_al-2018-Journal_of_Advances_in_Modeling_Earth_Systems.pdf
", "abstract": "An explicit prognostic cloud\u2010cover scheme (PROGCS) is implemented into the Global/Regional Assimilation and Prediction System (GRAPES) for global middle\u2010range numerical weather predication system (GRAPES_GFS) to improve the model performance in simulating cloud cover and radiation. Unlike the previous diagnostic cloud\u2010cover scheme (DIAGCS), PROGCS considers the formation and dissipation of cloud cover by physically connecting it to the cumulus convection and large\u2010scale stratiform condensation processes. Our simulation results show that clouds in mid\u2010high latitudes arise mainly from large\u2010scale stratiform condensation processes, while cumulus convection and large\u2010scale condensation processes jointly determine cloud cover in low latitudes. Compared with DIAGCS, PROGCS captures more consistent vertical distributions of cloud cover with the observations from Atmospheric Radiation Measurements (ARM) program at the Southern Great Plains (SGP) site and simulates more realistic diurnal cycle of marine stratocumulus with the ERA\u2010Interim reanalysis data. The low, high, and total cloud covers that are determined via PROGCS appear to be more realistic than those simulated via DIAGCS when both are compared with satellite retrievals though the former maintains slight negative biases. In addition, the simulations of outgoing longwave radiation (OLR) at the top of the atmosphere (TOA) from PROGCS runs have been considerably improved as well, resulting in less biases in radiative heating rates at heights below 850 hPa and above 400 hPa of GRAPES_GFS. Our results indicate that a prognostic method of cloud\u2010cover calculation has significant advantage over the conventional diagnostic one, and it should be adopted in both weather and climate simulation and forecast.", "date": "2018-03", "date_type": "published", "publication": "Journal of Advances in Modeling Earth Systems", "volume": "10", "number": "3", "publisher": "American Geophysical Union", "pagerange": "652-667", "id_number": "CaltechAUTHORS:20180221-155622227", "issn": "1942-2466", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180221-155622227", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Ministry of Science and Technology (Taipei)", "grant_number": "2017YFC1501403" }, { "agency": "Ministry of Science and Technology (Taipei)", "grant_number": "2017YFC1501406" }, { "agency": "National Natural Science Foundation of China", "grant_number": "41575143" }, { "agency": "National Natural Science Foundation of China", "grant_number": "41105067" }, { "agency": "National Natural Science Foundation of China", "grant_number": "41375107" }, { "agency": "Special Fund for Meteorology scientific Research in the Public Interest", "grant_number": "GYHY201506018" }, { "agency": "Special Fund for Meteorology scientific Research in the Public Interest", "grant_number": "GYHY201406005" }, { "agency": "State Key Laboratory of Earth Surface Processes and Resource Ecology", "grant_number": "2017-ZY-02" }, { "agency": "Fundamental Research Funds for the Central Universities" }, { "agency": "NSF", "grant_number": "AGS-1700727" }, { "agency": "NASA/JPL/Caltech" } ] }, "local_group": { "items": [ { "id": "Astronomy-Department" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1002/2017MS001234", "primary_object": { "basename": "Ma_et_al-2018-Journal_of_Advances_in_Modeling_Earth_Systems.pdf", "url": "https://authors.library.caltech.edu/records/tykxn-jh954/files/Ma_et_al-2018-Journal_of_Advances_in_Modeling_Earth_Systems.pdf" }, "resource_type": "article", "pub_year": "2018", "author_list": "Ma, Zhanshan; Liu, Qijun; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/8hzf4-dgh65", "eprint_id": 87830, "eprint_status": "archive", "datestamp": "2023-08-19 08:10:00", "lastmod": "2023-10-18 21:28:22", "type": "conference_item", "metadata_visibility": "show", "creators": { "items": [ { "id": "Mills-F-P", "name": { "family": "Mills", "given": "Franklin" } }, { "id": "Marcq-E", "name": { "family": "Marcq", "given": "Emmanuel" } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk" }, "orcid": "0000-0002-4263-2562" }, { "id": "Parkinson-C-D", "name": { "family": "Parkinson", "given": "Christopher" }, "orcid": "0000-0002-5722-2224" }, { "id": "Jessup-K-L", "name": { "family": "Jessup", "given": "Kandis Lea" } }, { "id": "Vandaele-A-C", "name": { "family": "Vandaele", "given": "Ann Carine" } } ] }, "title": "Atmospheric chemistry on Venus: An overview of unresolved issues", "ispublished": "unpub", "full_text_status": "restricted", "note": "\u00a9 2018 American Chemical Society.", "abstract": "Venus' atm. is 96.5% CO_2 and 3.5% N_2 with trace abundances of SO_2, OCS, H_2O, HCl, HF, and HBr, as well as their\nphotochem. and lightning-induced products. The global clouds are composed at least partly of concd. sulfuric acid. The\nsurface pressure is 90 atm and surface temps. exceed 700 K. Atm. chem. transitions from ion chem. through\nphotochem. to thermal equil. chem. with heterogeneous chem. likely throughout the atm. Three major chem. cycles have\nbeen identified: the carbon dioxide, sulfur oxidn., and polysulfur cycles. The carbon dioxide cycle includes CO_2\nphotolysis, transport of a significant fraction of CO and O to the night side, prodn. of O_2, and conversion of CO and O_2 to\nCO_2, possibly via chlorine catalyzed pathways. The sulfur oxidn. cycle comprises transport upward of OCS, SO_2, and\nH_2O, oxidn. to H_2SO_4, condensation to form the global 30-km thick cloud layers, and sulfuric acid rain. The polysulfur\ncycle involves the upward transport of OCS and SO_2, disproportionation and prodn. of S_x (x=2-8), and downward\ntransport of S_x to react with CO and SO_3. There is solid evidence for the carbon dioxide and sulfur oxidn. cycles; the\npolysulfur cycle is more speculative but plausible. Alternatively, sulfur chem. on Venus has been conceptually divided\ninto fast and slow atm. cycles and a geol. cycle. Recent work (Parkinson et al, PSS, 2015) suggests the ternary SO_2-H_2O-H_2SO_4 system may bifurcate depending on the relative abundances of H_2O and SO_2. Despite this general\nunderstanding, five decades of spacecraft, and 200 years of observation, numerous significant unresolved issues remain.\nOne is the means by which CO_2 is stabilized over geol. time - models predict O_2 abundances a factor of ten larger than\nthe observational upper limit. Another is the lack of consistency among models of the chem. and microphysics in\ndifferent regions, esp. in the cloud layers, where the mixing ratios of many important trace species change by orders of\nmagnitude within several vertical scale heights, and at the surface. A third is the mechanism(s) creating an inversion\nlayer in SO_2 abundances in the mesosphere. This talk presents an overview of our current understanding and key\nunresolved issues.", "date": "2018-03", "date_type": "published", "publisher": "Caltech Library", "id_number": "CaltechAUTHORS:20180713-125059321", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180713-125059321", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "local_group": { "items": [ { "id": "Astronomy-Department" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "resource_type": "conference_item", "pub_year": "2018", "author_list": "Mills, Franklin; Marcq, Emmanuel; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/s331m-cx567", "eprint_id": 83435, "eprint_status": "archive", "datestamp": "2023-08-21 22:36:55", "lastmod": "2023-10-17 23:07:36", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Young-L-A", "name": { "family": "Young", "given": "Leslie A." }, "orcid": "0000-0002-7547-3967" }, { "id": "Gao-Peter", "name": { "family": "Gao", "given": "Peter" }, "orcid": "0000-0002-8518-9601" }, { "id": "Wong-Michael-L", "name": { "family": "Wong", "given": "Michael L." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Structure and composition of Pluto's atmosphere from the New Horizons solar ultraviolet occultation", "ispublished": "pub", "full_text_status": "public", "keywords": "Pluto, atmosphere; Atmospheres, structure; Occultations; Ultraviolet observations; Triton, atmosphere; KBO atmospheres", "note": "\u00a9 2017 Elsevier Inc. \n\nReceived 5 April 2017, Revised 28 August 2017, Accepted 5 September 2017, Available online 8 September 2017. \n\nThis work was supported, in part, by funding from NASA's New Horizons mission to the Pluto system. The New Horizons Mission Design and Navigation teams enabled us to watch this glorious sunset and sunrise. Werner Curdt provided the high spectral-resolution solar models. We gratefully acknowledge the publicly available solar data and spectroscopic data: LISIRD Lyman-alpha data from http://lasp.colorado.edu/lisird/lya/, GOES15 soft X-ray flux from http://www.swpc.noaa.gov/; and the Titan spectroscopic database at http://www.lisa.univ-paris12.fr/GPCOS/SCOOPweb/. Thanks go out to Julie Moses for providing an electronic version of the C_2H_2 cross sections from Wu et al. (2001).\n\nAccepted Version - 1704.01511.pdf
Supplemental Material - 1-s2.0-S0019103517302609-mmc1.zip
Supplemental Material - 1-s2.0-S0019103517302609-mmc2.zip
Supplemental Material - 1-s2.0-S0019103517302609-mmc3.zip
Supplemental Material - 1-s2.0-S0019103517302609-mmc4.zip
Supplemental Material - 1-s2.0-S0019103517302609-mmc5.zip
Supplemental Material - 1-s2.0-S0019103517302609-mmc6.zip
", "abstract": "The Alice instrument on NASA's New Horizons spacecraft observed an ultraviolet solar occultation by Pluto's atmosphere on 2015 July 14. The transmission vs. altitude was sensitive to the presence of N_2, CH_4, C_2H_2, C_2H_4, C_2H_6, and haze. We derived line-of-sight abundances and local number densities for the 5 molecular species, and line-of-sight optical depth and extinction coefficients for the haze. We found the following major conclusions: (1) We confirmed temperatures in Pluto's upper atmosphere that were colder than expected before the New Horizons flyby, with upper atmospheric temperatures near 65\u201368 K. The inferred enhanced Jeans escape rates were (3\u20137) \u00d7 10^(22) N_2 s^(\u22121) and (4\u20138) \u00d7 10^(25) CH_4 s^(\u22121) at the exobase (at a radius of \u223c 2900 km, or an altitude of \u223c1710 km). (2) We measured CH_4 abundances from 80 to 1200 km above the surface. A joint analysis of the Alice CH_4 and Alice and REX N_2 measurements implied a very stable lower atmosphere with a small eddy diffusion coefficient, most likely between 550 and 4000 cm^2 s^(\u22121). Such a small eddy diffusion coefficient placed the homopause within 12 km of the surface, giving Pluto a small planetary boundary layer. The inferred CH_4 surface mixing ratio was \u223c 0.28\u20130.35%. (3) The abundance profiles of the \"C_2H_x hydrocarbons\" (C_2H_2, C_2H_4, C_2H_6) were not simply exponential with altitude. We detected local maxima in line-of-sight abundance near 410 km altitude for C_2H_4, near 320 km for C_2H_2, and an inflection point or the suggestion of a local maximum at 260 km for C_2H_6. We also detected local minima near 200 km altitude for C_2H_4, near 170 km for C_2H_2, and an inflection point or minimum near 170\u2013200 km for C_2H_6. These compared favorably with models for hydrocarbon production near 300\u2013400 km and haze condensation near 200 km, especially for C_2H_2 and C_2H_4 (Wong et al., 2017). (4) We found haze that had an extinction coefficient approximately proportional to N_2 density.", "date": "2018-01-15", "date_type": "published", "publication": "Icarus", "volume": "300", "publisher": "Elsevier", "pagerange": "174-199", "id_number": "CaltechAUTHORS:20171127-075151635", "issn": "0019-1035", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20171127-075151635", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA" } ] }, "local_group": { "items": [ { "id": "Astronomy-Department" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/j.icarus.2017.09.006", "primary_object": { "basename": "1-s2.0-S0019103517302609-mmc3.zip", "url": "https://authors.library.caltech.edu/records/s331m-cx567/files/1-s2.0-S0019103517302609-mmc3.zip" }, "related_objects": [ { "basename": "1-s2.0-S0019103517302609-mmc4.zip", "url": "https://authors.library.caltech.edu/records/s331m-cx567/files/1-s2.0-S0019103517302609-mmc4.zip" }, { "basename": "1-s2.0-S0019103517302609-mmc5.zip", "url": "https://authors.library.caltech.edu/records/s331m-cx567/files/1-s2.0-S0019103517302609-mmc5.zip" }, { "basename": "1-s2.0-S0019103517302609-mmc6.zip", "url": "https://authors.library.caltech.edu/records/s331m-cx567/files/1-s2.0-S0019103517302609-mmc6.zip" }, { "basename": "1704.01511.pdf", "url": "https://authors.library.caltech.edu/records/s331m-cx567/files/1704.01511.pdf" }, { "basename": "1-s2.0-S0019103517302609-mmc1.zip", "url": "https://authors.library.caltech.edu/records/s331m-cx567/files/1-s2.0-S0019103517302609-mmc1.zip" }, { "basename": "1-s2.0-S0019103517302609-mmc2.zip", "url": "https://authors.library.caltech.edu/records/s331m-cx567/files/1-s2.0-S0019103517302609-mmc2.zip" } ], "resource_type": "article", "pub_year": "2018", "author_list": "Young, Leslie A.; Gao, Peter; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/3gcg3-khn91", "eprint_id": 86060, "eprint_status": "archive", "datestamp": "2023-08-19 07:11:55", "lastmod": "2023-10-18 19:13:51", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Chen-Pin", "name": { "family": "Chen", "given": "Pin" } }, { "id": "Nealson-K-H", "name": { "family": "Nealson", "given": "Kenneth" }, "orcid": "0000-0001-5189-3732" }, { "id": "Atreya-S-K", "name": { "family": "Atreya", "given": "Sushil" }, "orcid": "0000-0002-1972-1815" }, { "id": "Beckett-P", "name": { "family": "Beckett", "given": "Patrick" } }, { "id": "Blank-J-G", "name": { "family": "Blank", "given": "Jennifer" } }, { "id": "Ehlmann-B-L", "name": { "family": "Ehlmann", "given": "Bethany" }, "orcid": "0000-0002-2745-3240" }, { "id": "Eiler-J-M", "name": { "family": "Eiler", "given": "John" } }, { "id": "Etiope-G", "name": { "family": "Etiope", "given": "Giuseppe" } }, { "id": "Ferry-J-G", "name": { "family": "Ferry", "given": "James G." } }, { "id": "Forget-F", "name": { "family": "Forget", "given": "Francois" } }, { "id": "Gao-Peter", "name": { "family": "Gao", "given": "Peter" }, "orcid": "0000-0002-8518-9601" }, { "id": "Hu-Renyu", "name": { "family": "Hu", "given": "Renyu" }, "orcid": "0000-0003-2215-8485" }, { "id": "Kleinb\u00f6hl-A", "name": { "family": "Kleinb\u00f6hl", "given": "Armin" } }, { "id": "Klusman-R", "name": { "family": "Klusman", "given": "Ronald" } }, { "id": "Lef\u00e8vre-F", "name": { "family": "Lef\u00e8vre", "given": "Franck" } }, { "id": "Miller-C-E", "name": { "family": "Miller", "given": "Charles" }, "orcid": "0000-0002-9380-4838" }, { "id": "Mischna-M-A", "name": { "family": "Mischna", "given": "Michael" }, "orcid": "0000-0002-8022-5319" }, { "id": "Mumma-M-J", "name": { "family": "Mumma", "given": "Michael" } }, { "id": "Newman-S", "name": { "family": "Newman", "given": "Sally" }, "orcid": "0000-0003-0710-995X" }, { "id": "Oehler-D-Z", "name": { "family": "Oehler", "given": "Dorothy" } }, { "id": "Okumura-M", "name": { "family": "Okumura", "given": "Mitchio" }, "orcid": "0000-0001-6874-1137" }, { "id": "Oremland-R-S", "name": { "family": "Oremland", "given": "Ronald" } }, { "id": "Orphan-V-J", "name": { "family": "Orphan", "given": "Victoria" }, "orcid": "0000-0002-5374-6178" }, { "id": "Popa-R", "name": { "family": "Popa", "given": "Radu" } }, { "id": "Russell-M-J", "name": { "family": "Russell", "given": "Michael" } }, { "id": "Shen-Linhan", "name": { "family": "Shen", "given": "Linhan" }, "orcid": "0000-0003-3871-655X" }, { "id": "Sherwood-Lollar-B", "name": { "family": "Sherwood Lollar", "given": "Barbara" } }, { "id": "Stamenkovi\u0107-V", "name": { "family": "Stamenkovi\u0107", "given": "Vlada" }, "orcid": "0000-0003-2416-3683" }, { "id": "Staehle-R-L", "name": { "family": "Staehle", "given": "Robert" } }, { "id": "Stolper-D-A", "name": { "family": "Stolper", "given": "Daniel" }, "orcid": "0000-0003-3299-3177" }, { "id": "Templeton-A", "name": { "family": "Templeton", "given": "Alexis" } }, { "id": "Vandaele-A-C", "name": { "family": "Vandaele", "given": "Ann C." } }, { "id": "Viscardy-S", "name": { "family": "Viscardy", "given": "S\u00e9bastien" } }, { "id": "Webster-C-R", "name": { "family": "Webster", "given": "Chris" } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Wong-Michael-L", "name": { "family": "Wong", "given": "Michael" } }, { "id": "Worden-J-R", "name": { "family": "Worden", "given": "John" }, "orcid": "0000-0003-0257-9549" } ] }, "title": "Methane on Mars and Habitability: Challenges and Responses", "ispublished": "unpub", "full_text_status": "public", "note": "Study Report prepared for the Keck Institute for Space Studies (KISS).\n\nWe dedicate this report to JPL scientist Mark Allen, whose spirit of generosity inspired many of the conversations and much of the work that brought us together. We thank the Director of the Keck Institute for Space Studies, Tom Prince, the Executive Director, Michele Judd, and the fantastic KISS staff for hosting our workshop and providing a wonderful environment for these discussions.\n\nAccepted Version - Methane_final_report.pdf
", "abstract": "Recent measurements of methane (CH_4) by the Mars Science Laboratory (MSL) now confront us with robust data that demand interpretation. Thus far, the MSL data have revealed a baseline level of CH_4 (\u223c0.4 parts per billion by volume [ppbv]), with seasonal variations, as well as greatly enhanced spikes of CH_4 with peak abundances of \u223c7\u2009ppbv. What do these CH_4 revelations with drastically different abundances and temporal signatures represent in terms of interior geochemical processes, or is martian CH_4 a biosignature? Discerning how CH_4 generation occurs on Mars may shed light on the potential habitability of Mars. There is no evidence of life on the surface of Mars today, but microbes might reside beneath the surface. In this case, the carbon flux represented by CH_4 would serve as a link between a putative subterranean biosphere on Mars and what we can measure above the surface. Alternatively, CH_4 records modern geochemical activity. Here we ask the fundamental question: how active is Mars, geochemically and/or biologically? In this article, we examine geological, geochemical, and biogeochemical processes related to our overarching question. The martian atmosphere and surface are an overwhelmingly oxidizing environment, and life requires pairing of electron donors and electron acceptors, that is, redox gradients, as an essential source of energy. Therefore, a fundamental and critical question regarding the possibility of life on Mars is, \"Where can we find redox gradients as energy sources for life on Mars?\" Hence, regardless of the pathway that generates CH_4 on Mars, the presence of CH_4, a reduced species in an oxidant-rich environment, suggests the possibility of redox gradients supporting life and habitability on Mars. Recent missions such as ExoMars Trace Gas Orbiter may provide mapping of the global distribution of CH_4. To discriminate between abiotic and biotic sources of CH_4 on Mars, future studies should use a series of diagnostic geochemical analyses, preferably performed below the ground or at the ground/atmosphere interface, including measurements of CH_4 isotopes, methane/ethane ratios, H_2 gas concentration, and species such as acetic acid. Advances in the fields of Mars exploration and instrumentation will be driven, augmented, and supported by an improved understanding of atmospheric chemistry and dynamics, deep subsurface biogeochemistry, astrobiology, planetary geology, and geophysics. Future Mars exploration programs will have to expand the integration of complementary areas of expertise to generate synergistic and innovative ideas to realize breakthroughs in advancing our understanding of the potential of life and habitable conditions having existed on Mars. In this spirit, we conducted a set of interdisciplinary workshops. From this series has emerged a vision of technological, theoretical, and methodological innovations to explore the martian subsurface and to enhance spatial tracking of key volatiles, such as CH_4.", "date": "2018-01", "date_type": "published", "publisher": "Astrobiology", "id_number": "CaltechAUTHORS:20180426-110252898", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180426-110252898", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "local_group": { "items": [ { "id": "Keck-Institute-for-Space-Studies" }, { "id": "Astronomy-Department" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.7907/Z990220K", "primary_object": { "basename": "Methane_final_report.pdf", "url": "https://authors.library.caltech.edu/records/3gcg3-khn91/files/Methane_final_report.pdf" }, "resource_type": "monograph", "pub_year": "2018", "author_list": "Yung, Yuk L.; Chen, Pin; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/a6sfa-x2505", "eprint_id": 80639, "eprint_status": "archive", "datestamp": "2023-08-19 05:17:37", "lastmod": "2023-10-17 16:58:54", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Kite-E-S", "name": { "family": "Kite", "given": "Edwin S." }, "orcid": "0000-0002-1426-1186" }, { "id": "Gao-Peter", "name": { "family": "Gao", "given": "Peter" }, "orcid": "0000-0002-8518-9601" }, { "id": "Goldblatt-C", "name": { "family": "Goldblatt", "given": "Colin" } }, { "id": "Mischna-M-A", "name": { "family": "Mischna", "given": "Michael A." }, "orcid": "0000-0002-8022-5319" }, { "id": "Mayer-D-P", "name": { "family": "Mayer", "given": "David P." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Methane bursts as a trigger for intermittent lake-forming climates on post-Noachian Mars", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2017 Macmillan Publishers Limited, part of Springer Nature. \n\nReceived 25 May 2017; Accepted 23 August 2017; Published online 02 October 2017. \n\nWe are grateful for input from D. E. Archer, J. C. Armstrong, B. L. Ehlmann, V. E. Hamilton, A. D. Howard, R. P. III Irwin, M. C. Palucis, D. Stolper, R. M. E. Williams and R. Wordsworth. We thank J. F. Kasting and A. G. Fair\u00e9n for useful reviews. Part of the research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration. We acknowledge the University of Chicago's Research Computing Center and financial support from NASA (NNX16AG55G, NNX15AM49G). \n\nAuthor Contributions: E.S.K. designed research; M.A.M., Y.L.Y. and D.P.M. contributed new models, model output, and analyses; E.S.K., C.G. and P.G. carried out research; and E.S.K. wrote the paper. \n\nThe authors declare no competing financial interests. \n\nCode availability: The methane burst code is available from the corresponding author upon request. The GCM and photochemical codes are not available. \n\nData availability: The materials that support the findings of this study and the figures in this paper, including computer code, are available from the corresponding author upon request.\n\nSubmitted - 1611.01717.pdf
Supplemental Material - ngeo3033-s1.pdf
", "abstract": "Lakes existed on Mars later than 3.6 billion years ago, according to sedimentary evidence for deltaic deposition. The observed fluviolacustrine deposits suggest that individual lake-forming climates persisted for at least several thousand years (assuming dilute flow). But the lake watersheds' little-weathered soils indicate a largely dry climate history, with intermittent runoff events. Here we show that these observational constraints, although inconsistent with many previously proposed triggers for lake-forming climates, are consistent with a methane burst scenario. In this scenario, chaotic transitions in mean obliquity drive latitudinal shifts in temperature and ice loading that destabilize methane clathrate. Using numerical simulations, we find that outgassed methane can build up to atmospheric levels sufficient for lake-forming climates, if methane clathrate initially occupies more than 4% of the total volume in which it is thermodynamically stable. Such occupancy fractions are consistent with methane production by water\u2013rock reactions due to hydrothermal circulation on early Mars. We further estimate that photochemical destruction of atmospheric methane curtails the duration of individual lake-forming climates to less than a million years, consistent with observations. We conclude that methane bursts represent a potential pathway for intermittent excursions to a warm, wet climate state on early Mars.", "date": "2017-10", "date_type": "published", "publication": "Nature Geoscience", "volume": "10", "number": "10", "publisher": "Nature Publishing Group", "pagerange": "737-740", "id_number": "CaltechAUTHORS:20170821-105332756", "issn": "1752-0894", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170821-105332756", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA/JPL/Caltech" }, { "agency": "NASA", "grant_number": "NNX16AG55G" }, { "agency": "NASA", "grant_number": "NNX15AM49G" } ] }, "collection": "CaltechAUTHORS", "local_group": { "items": [ { "id": "Astronomy-Department", "value": "Astronomy Department" }, { "id": "Division-of-Geological-and-Planetary-Sciences", "value": "Division of Geological and Planetary Sciences" } ] }, "doi": "10.1038/ngeo3033", "primary_object": { "basename": "ngeo3033-s1.pdf", "url": "https://authors.library.caltech.edu/records/a6sfa-x2505/files/ngeo3033-s1.pdf" }, "related_objects": [ { "basename": "1611.01717.pdf", "url": "https://authors.library.caltech.edu/records/a6sfa-x2505/files/1611.01717.pdf" } ], "resource_type": "article", "pub_year": "2017", "author_list": "Kite, Edwin S.; Gao, Peter; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/mkez6-bf646", "eprint_id": 82391, "eprint_status": "archive", "datestamp": "2023-08-21 21:52:56", "lastmod": "2023-10-17 22:15:08", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Wong-Michael-L", "name": { "family": "Wong", "given": "Michael L." } }, { "id": "Charnay-B-D", "name": { "family": "Charnay", "given": "Benjamin D." } }, { "id": "Gao-Peter", "name": { "family": "Gao", "given": "Peter" }, "orcid": "0000-0002-8518-9601" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Russell-M-J", "name": { "family": "Russell", "given": "Michael J." } } ] }, "title": "Nitrogen Oxides in Early Earth's Atmosphere as Electron Acceptors for Life's Emergence", "ispublished": "pub", "full_text_status": "public", "keywords": "Nitrogen oxides; Nitrate; Nitrite; Photochemistry; Lightning; Emergence of life", "note": "\u00a9 2017 Mary Ann Liebert, Inc. \n\nSubmitted 25 January 2016; Accepted 22 March 2017; Online Ahead of Print: October 12, 2017. \n\nThis research was supported in part by an NAI Virtual Planetary Laboratory grant from the University of Washington to the Jet Propulsion Laboratory and California Institute of Technology. B.D.C. acknowledges support from an appointment to the NASA Postdoctoral Program, administered by Universities Space Research Association. M.J.R.'s research was supported by the National Aeronautics and Space Administration, through the NASA Astrobiology Institute under cooperative agreement issued through the Science Mission directorate; No. NNH13ZDA017C (Icy Worlds) at the Jet Propulsion Laboratory. \n\nNo competing financial interests exist.\n\nPublished - ast.2016.1473.pdf
", "abstract": "We quantify the amount of nitrogen oxides (NOx) produced through lightning and photochemical processes in the Hadean atmosphere to be available in the Hadean ocean for the emergence of life. Atmospherically generated nitrate (NO_3\u2212) and nitrite (NO_2\u2212) are the most attractive high-potential electron acceptors for pulling and enabling crucial redox reactions of autotrophic metabolic pathways at submarine alkaline hydrothermal vents. The Hadean atmosphere, dominated by CO_2 and N_2, will produce nitric oxide (NO) when shocked by lightning. Photochemical reactions involving NO and H_2O vapor will then produce acids such as HNO, HNO_2, HNO_3, and HO_2NO_2 that rain into the ocean. There, they dissociate into or react to form nitrate and nitrite. We present new calculations based on a novel combination of early-Earth global climate model and photochemical modeling, and we predict the flux of NOx to the Hadean ocean. In our 0.1-, 1-, and 10-bar pCO_2 models, we calculate the NOx delivery to be 2.4\u2009\u00d7\u200910^5, 6.5\u2009\u00d7\u200910^8, and 1.9\u2009\u00d7\u200910^8 molecules cm^(\u22122) s^(\u22121). After only tens of thousands to tens of millions of years, these NOx fluxes are expected to produce sufficient (micromolar) ocean concentrations of high-potential electron acceptors for the emergence of life.", "date": "2017-10", "date_type": "published", "publication": "Astrobiology", "volume": "17", "number": "10", "publisher": "Mary Ann Liebert", "pagerange": "975-983", "id_number": "CaltechAUTHORS:20171016-153957584", "issn": "1531-1074", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20171016-153957584", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "University of Washington" }, { "agency": "NASA Postdoctoral Program" }, { "agency": "NASA", "grant_number": "NNH13ZDA017C" } ] }, "local_group": { "items": [ { "id": "Astronomy-Department" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1089/ast.2016.1473", "primary_object": { "basename": "ast.2016.1473.pdf", "url": "https://authors.library.caltech.edu/records/mkez6-bf646/files/ast.2016.1473.pdf" }, "resource_type": "article", "pub_year": "2017", "author_list": "Wong, Michael L.; Charnay, Benjamin D.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/1pzx5-07w41", "eprint_id": 77615, "eprint_status": "archive", "datestamp": "2023-08-19 04:49:01", "lastmod": "2023-10-25 23:18:13", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Kopparla-P", "name": { "family": "Kopparla", "given": "Pushkar" }, "orcid": "0000-0002-8951-3907" }, { "id": "Natraj-V", "name": { "family": "Natraj", "given": "Vijay" }, "orcid": "0000-0003-3154-9429" }, { "id": "Limpasuvan-D", "name": { "family": "Limpasuvan", "given": "Drew" } }, { "id": "Spurr-R-J-D", "name": { "family": "Spurr", "given": "Robert" } }, { "id": "Crisp-D", "name": { "family": "Crisp", "given": "David" }, "orcid": "0000-0002-4573-9998" }, { "id": "Shia-Run-Lie", "name": { "family": "Shia", "given": "Run-Lie" }, "orcid": "0000-0003-1911-3120" }, { "id": "Somkuti-P", "name": { "family": "Somkuti", "given": "Peter" }, "orcid": "0000-0002-5858-8471" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "PCA-based radiative transfer: Improvements to aerosol scheme, vertical layering and spectral binning", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2017 Elsevier Ltd. \n\nReceived 18 February 2017, Revised 8 May 2017, Accepted 8 May 2017, Available online 9 May 2017.", "abstract": "The Principal Component Analysis (PCA)-based fast radiative transfer method has been shown to have at least an order of magnitude increase in computational speed while maintaining an overall accuracy of 0.01% (compared to line-by-line calculations) over narrow and broad spectral bands. In this paper, we describe several improvements made to the method and provide a discussion of the method's performance over a diverse set of atmospheric profiles and land surface types. We also test the model over uniform pressure level profiles. The method is now capable of providing atmospheric spectra with residuals under 0.1%, calculated with respect to the continuum, throughout the shortwave region between 0.3\u22123\u03bcm at high resolution, which is substantial improvement over errors reported in earlier work. Future directions for applications and further optimization are examined.", "date": "2017-09", "date_type": "published", "publication": "Journal of Quantitative Spectroscopy and Radiative Transfer", "volume": "198", "publisher": "Elsevier", "pagerange": "104-111", "id_number": "CaltechAUTHORS:20170522-075457610", "issn": "0022-4073", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170522-075457610", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "local_group": { "items": [ { "id": "Astronomy-Department" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/j.jqsrt.2017.05.005", "resource_type": "article", "pub_year": "2017", "author_list": "Kopparla, Pushkar; Natraj, Vijay; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/hhxkk-jnt62", "eprint_id": 80813, "eprint_status": "archive", "datestamp": "2023-08-21 21:39:37", "lastmod": "2023-10-17 18:30:37", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Kao-Anglea", "name": { "family": "Kao", "given": "Angela" } }, { "id": "Jiang-Xun", "name": { "family": "Jiang", "given": "Xun" }, "orcid": "0000-0001-8932-3807" }, { "id": "Li-Liming", "name": { "family": "Li", "given": "Liming" }, "orcid": "0000-0002-5257-9849" }, { "id": "Su-Hui", "name": { "family": "Su", "given": "Hui" }, "orcid": "0000-0003-1265-9702" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk" }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Precipitation, Circulation, and Cloud Variability Over the Past Two Decades", "ispublished": "pub", "full_text_status": "public", "keywords": "precipitation variation; circulation and cloud; model simulations", "note": "\u00a9 2017 The Authors. This is an open access article under the terms of the Creative Commons Attribution-NonCommercial-NoDerivs License, which permits use and distribution in any medium, provided the original work is properly cited, the use is non-commercial and no modifications or adaptations are made. \n\nReceived 5 JUL 2017; Accepted 22 AUG 2017; Accepted article online 24 AUG 2017; Published online 8 SEP 2017. \n\nWe thank an anonymous reviewer and the Editor for their time and helpful comments. The authors (Jiang and Kao) at the University of Houston and coauthor (Yung) at the California Institute of Technology were supported by NASA grants NNX13AC04G and NNX13AK34G. The coauthor (Su) at the Jet Propulsion Laboratory, California Institute of Technology, under contract with NASA, acknowledges the funding support from the NASA NEWS project. The coauthor (Li) at the University of Houston was supported by the NASA PDART program. GPCP V2.2 data are provided by the center of Earth System Research Laboratory at http://www.esrl.noaa.gov/psd/data/gridded/data.gpcp.html. NCEP2 data are available at http://www.esrl.noaa.gov/psd/data/gridded/data.ncep.reanalysis2.html.\n\nPublished - Kao_et_al-2017-Earth_and_Space_Science.pdf
Supplemental Material - ess2144-sup-0001-2017EA000319-S01.docx
", "abstract": "To better understand the variability of precipitation, circulation, and cloud, we examine the precipitation, vertical velocity, total cloud fraction, condensed water path, and ice water path from observations and 13 Coupled Model Intercomparison Project 5 (CMIP5) models over 1988\u20132008. All variables are averaged over wet areas and dry areas to investigate temporal variations of different variables over these regions. We found that all models demonstrate similar temporal variations of precipitation as the observational data from the Global Precipitation Climatology Project, with positive trend over wet areas (6.22 \u00b1 3.75 mm/mon/decade) and negative trend over dry areas (\u22120.77 \u00b1 0.54 mm/mon/decade). Positive trends of vertical velocity, total cloud fraction, condensed water path, and ice water path are also found in the observations and models over the wet areas. Observations also demonstrate decreasing trends of vertical velocity, total clouds, condensed water path, and ice water path over the dry areas, which can be simulated by most models with a few exceptions. The qualitatively consistent trends in these variables (i.e., vertical velocity, cloud, liquid, and ice water contents) as revealed from the observations and CMIPS models provide a clearer picture of the dynamics and physics behind the temporal variations of precipitation over different areas.", "date": "2017-09", "date_type": "published", "publication": "Earth and Space Science", "volume": "4", "number": "9", "publisher": "American Geophysical Union", "pagerange": "597-606", "id_number": "CaltechAUTHORS:20170825-152143722", "issn": "2333-5084", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170825-152143722", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NNX13AC04G" }, { "agency": "NASA", "grant_number": "NNX13AK34G" }, { "agency": "NASA/JPL/Caltech" } ] }, "local_group": { "items": [ { "id": "Astronomy-Department" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1002/2017EA000319", "primary_object": { "basename": "Kao_et_al-2017-Earth_and_Space_Science.pdf", "url": "https://authors.library.caltech.edu/records/hhxkk-jnt62/files/Kao_et_al-2017-Earth_and_Space_Science.pdf" }, "related_objects": [ { "basename": "ess2144-sup-0001-2017EA000319-S01.docx", "url": "https://authors.library.caltech.edu/records/hhxkk-jnt62/files/ess2144-sup-0001-2017EA000319-S01.docx" } ], "resource_type": "article", "pub_year": "2017", "author_list": "Kao, Angela; Jiang, Xun; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/vp2qy-9r438", "eprint_id": 81117, "eprint_status": "archive", "datestamp": "2023-08-19 04:53:47", "lastmod": "2023-10-17 19:34:53", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Li-King-Fai", "name": { "family": "Li", "given": "King-Fai" }, "orcid": "0000-0003-0150-2910" }, { "id": "Zhang-Qiong", "name": { "family": "Zhang", "given": "Qiong" }, "orcid": "0000-0002-8762-0557" }, { "id": "Wang-Shuhui", "name": { "family": "Wang", "given": "Shuhui" } }, { "id": "Sander-S-P", "name": { "family": "Sander", "given": "Stanley P." }, "orcid": "0000-0003-1424-3620" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Resolving the model-observation discrepancy in the mesospheric and stratospheric HO_x chemistry", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2017 American Geophysical Union. This is an open access article under the terms of the Creative Commons Attribution-NonCommercial-NoDerivs License, which permits use and distribution in any medium, provided the original work is properly cited, the use is non-commercial and no modifications or adaptations are made. \n\nReceived 12 APR 2017; Accepted 28 AUG 2017; Accepted article online 4 SEP 2017; Published online 27 SEP 2017.\n\nWe thank P. Wennberg, R. -L. Shia, S. Newman, and P. Kopparla for helpful comments. We acknowledge the support of the NASA Aura Science Team. S. W., Q. Z., and Y. L. Y. acknowledge partial support by NASA's LWS Program grant NNX16AK63G. K. F. L. was supported partly by the Jack Eddy Fellowship managed by the University Corporation for Atmospheric Research and partly by the NASA grant NNX14AR40G. We thank the two anonymous reviewers, whose comments significantly improved this manuscript. Additional support was provided by the NASA Upper Atmosphere Research and Tropospheric Chemistry Programs. MLS data are available at https://mls.jpl.nasa.gov/products/oh_product.php.\n\nPublished - ef5f63e0d1351e329eb0885a71ee7be833e87985d56cc600da66cf5caf924138.pdf
Accepted Version - Li_et_al-2017-Earth_and_Space_Science.pdf
Supplemental Material - ess2157-sup-0001-2017EA000283-S01.pdf
", "abstract": "We examine the middle atmospheric odd-hydrogen (HO_x) chemistry by comparing the Aura Microwave Limb Sounder (MLS) OH and HO_2 measurements with a photochemical model simulation. The model underestimates mesospheric OH and HO_2 concentrations if the standard chemical kinetic rates are used, whether the model H_2O and O_3 are constrained with observations or not. To resolve the discrepancies, we adjust the kinetic rate coefficients of three key reactions (O + OH \u2192 O_2 + H, OH + HO_2 \u2192 H_2O + O_2, and H + O_2 + M \u2192 HO_2 + M) and the O2photo absorption cross section at Lyman-\u03b1 (121.57 nm) using the Bayesian optimal estimation. A much better model-observation agreement can be achieved if the kinetic rate coefficients for H + O_2 + M \u2192 HO_2 + M is increased by 134\u2013310%, and the O_2 photo absorption cross section at Lyman-\u03b1 is reduced by 33\u201354%, while the kinetic rate coefficients for O + OH \u2192 O_2 + H and OH + HO_2 \u2192 H_2O + O_2 remain consistent with the current laboratory values. The kinetic rate coefficient for H + O_2 + M \u2192 HO_2 + M requires a very large adjustment beyond the uncertainty limits recommended in the NASA Data Evaluation, suggesting the need for future laboratory measurements. An alternative explanation is that the radiative association reaction, H + O_2 \u2192 HO_2 + h\u03bd, plays a significant role, which has never been measured. Our results demonstrate that high quality satellite observations can be used to constrain photochemical parameters and help improve our understanding of atmospheric chemistry.", "date": "2017-09", "date_type": "published", "publication": "Earth and Space Science", "volume": "4", "number": "9", "publisher": "American Geophysical Union", "pagerange": "607-624", "id_number": "CaltechAUTHORS:20170905-074402925", "issn": "2333-5084", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170905-074402925", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NNX16AK63G" }, { "agency": "University Corporation for Atmospheric Research" }, { "agency": "NASA", "grant_number": "NNX14AR40G" } ] }, "local_group": { "items": [ { "id": "Astronomy-Department" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1002/2017EA000283", "primary_object": { "basename": "Li_et_al-2017-Earth_and_Space_Science.pdf", "url": "https://authors.library.caltech.edu/records/vp2qy-9r438/files/Li_et_al-2017-Earth_and_Space_Science.pdf" }, "related_objects": [ { "basename": "ef5f63e0d1351e329eb0885a71ee7be833e87985d56cc600da66cf5caf924138.pdf", "url": "https://authors.library.caltech.edu/records/vp2qy-9r438/files/ef5f63e0d1351e329eb0885a71ee7be833e87985d56cc600da66cf5caf924138.pdf" }, { "basename": "ess2157-sup-0001-2017EA000283-S01.pdf", "url": "https://authors.library.caltech.edu/records/vp2qy-9r438/files/ess2157-sup-0001-2017EA000283-S01.pdf" } ], "resource_type": "article", "pub_year": "2017", "author_list": "Li, King-Fai; Zhang, Qiong; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/x1c0d-b9j97", "eprint_id": 90287, "eprint_status": "archive", "datestamp": "2023-08-21 21:36:05", "lastmod": "2023-10-18 23:20:37", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Jiang-Xun", "name": { "family": "Jiang", "given": "Xun" }, "orcid": "0000-0001-8932-3807" }, { "id": "Kao-Anglea", "name": { "family": "Kao", "given": "Angela" } }, { "id": "Corbett-A", "name": { "family": "Corbett", "given": "Abigail" } }, { "id": "Olsen-E", "name": { "family": "Olsen", "given": "Edward" } }, { "id": "Pagano-T-S", "name": { "family": "Pagano", "given": "Thomas" } }, { "id": "Zhai-Albert", "name": { "family": "Zhai", "given": "Albert" } }, { "id": "Newman-S", "name": { "family": "Newman", "given": "Sally" }, "orcid": "0000-0003-0710-995X" }, { "id": "Li-Liming", "name": { "family": "Li", "given": "Liming" }, "orcid": "0000-0002-5257-9849" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk" }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Influence of Droughts on Mid-Tropospheric CO_2", "ispublished": "pub", "full_text_status": "public", "keywords": "drought; Carbon Dioxide; carbon cycle", "note": "\u00a9 2017 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/). \n\nReceived: 16 June 2017 / Revised: 13 August 2017 / Accepted: 15 August 2017 / Published: 17 August 2017. \n\n(This article belongs to the Special Issue Remote Sensing of Greenhouse Gases) \n\nWe thank three anonymous referees and editor for their time and helpful comments. X.J. and Y.Y. were supported by NASA grants NNX13AC04G and NNX13AK34G. E.O. and T.P. conducted the work at the Jet Propulsion Laboratory, under contract with NASA. L.L. was supported by NASA ROSES Cassini Data Analysis and NASA grant NNH15ZDA001N-PDART. \n\nAuthor Contributions: X.J. and A.K. conducted the analysis and wrote the manuscript. A.C., E.O., T.P., A.Z., S.N., L.L., and Y.Y. contributed to the result discussions and manuscript preparation. \n\nThe authors declare no competing financial interest.\n\nPublished - remotesensing-09-00852.pdf
Supplemental Material - remotesensing-09-00852-s001.pdf
", "abstract": "Using CO_2 data from the Atmospheric Infrared Sounder (AIRS), it is found for the first time that the mid-tropospheric CO_2 concentration is ~1 part per million by volume higher during dry years than wet years over the southwestern USA from June to September. The mid-tropospheric CO_2 differences between dry and wet years are related to circulation and CO_2 surface fluxes. During drought conditions, vertical pressure velocity from NCEP2 suggests that there is more rising air over most regions, which can help bring high surface concentrations of CO_2 to the mid-troposphere. In addition to the circulation, there is more CO_2 emitted from the biosphere to the atmosphere during droughts in some regions, which can contribute to higher concentrations of CO_2 in the atmosphere. Results obtained from this study demonstrate the significant impact of droughts on atmospheric CO_2 and therefore on a feedback cycle contributing to greenhouse gas warming. It can also help us better understand atmospheric CO_2, which plays a critical role in our climate system.", "date": "2017-08-17", "date_type": "published", "publication": "Remote Sensing", "volume": "9", "number": "8", "publisher": "MDPI", "pagerange": "Art. No. 852", "id_number": "CaltechAUTHORS:20181016-153901770", "issn": "2072-4292", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20181016-153901770", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NNX13AC04G" }, { "agency": "NASA", "grant_number": "NNX13AK34G" }, { "agency": "NASA/JPL" }, { "agency": "NASA", "grant_number": "NNH15ZDA001N-PDART" } ] }, "local_group": { "items": [ { "id": "Astronomy-Department" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.3390/rs9080852", "primary_object": { "basename": "remotesensing-09-00852-s001.pdf", "url": "https://authors.library.caltech.edu/records/x1c0d-b9j97/files/remotesensing-09-00852-s001.pdf" }, "related_objects": [ { "basename": "remotesensing-09-00852.pdf", "url": "https://authors.library.caltech.edu/records/x1c0d-b9j97/files/remotesensing-09-00852.pdf" } ], "resource_type": "article", "pub_year": "2017", "author_list": "Jiang, Xun; Kao, Angela; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/tb3za-7qa84", "eprint_id": 105450, "eprint_status": "archive", "datestamp": "2023-08-22 01:36:00", "lastmod": "2023-10-20 22:00:36", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Hendrix-A-R", "name": { "family": "Hendrix", "given": "Amanda R." }, "orcid": "0000-0002-0435-8224" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Energy Options for Future Humans on Titan", "ispublished": "pub", "full_text_status": "public", "keywords": "Titan; ISRU; Planetary environments", "note": "\u00a9 2017 Hendrix AR, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. \n\nReceived date: May 29, 2017; Accepted date: June 6, 2017; Published date: June 16, 2017. \n\nThe authors are grateful to Ralph Lorenz and Jason Barnes for helpful comments on an earlier version of this paper, and to Aimee Oz for help with chemical energy calculations.\n\nPublished - energy-options-for-future-humans-on-titan-2332-2519-1000157.pdf
", "abstract": "We review the possibilities for in situ energy resources on Titan for use by future humans, including chemical,\nnuclear, wind, solar, geothermal and hydropower. All of these options, with the possible exception of geothermal,\nrepresent effective sources of power. Combustion of methane (after electrolysis of the native water), in combination\nwith another source of power such as nuclear, is a viable option; another chemical source of energy is the\nhydrogenation of acetylene. The large seas Kraken and Ligeia potentially represent effective sources of hydropower.\nWind power, particularly at altitudes ~40 km, is expected to be productive. Despite the distance from the sun and the\nabsorbing atmosphere, solar power is (as on Earth) an extremely efficient source of power on Titan.", "date": "2017-07-24", "date_type": "published", "publication": "Journal of Astrobiology & Outreach", "volume": "5", "number": "2", "publisher": "OMICS Publishing Group", "pagerange": "Art. No. 1000157", "id_number": "CaltechAUTHORS:20200918-104150019", "issn": "2332-2519", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200918-104150019", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.4172/2332-2519.1000157", "primary_object": { "basename": "energy-options-for-future-humans-on-titan-2332-2519-1000157.pdf", "url": "https://authors.library.caltech.edu/records/tb3za-7qa84/files/energy-options-for-future-humans-on-titan-2332-2519-1000157.pdf" }, "resource_type": "article", "pub_year": "2017", "author_list": "Hendrix, Amanda R. and Yung, Yuk L." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/x6pr7-edn64", "eprint_id": 72919, "eprint_status": "archive", "datestamp": "2023-09-15 05:34:48", "lastmod": "2023-10-23 21:19:15", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Stock-J-W", "name": { "family": "Stock", "given": "Joachim W." } }, { "id": "Blaszczak-Boxe-C-S", "name": { "family": "Blaszczak-Boxe", "given": "Christopher S." }, "orcid": "0000-0002-5288-961X" }, { "id": "Lehmann-R", "name": { "family": "Lehmann", "given": "Ralph" } }, { "id": "Grenfell-J-L", "name": { "family": "Grenfell", "given": "J. Lee" } }, { "id": "Patzer-A-B-C", "name": { "family": "Patzer", "given": "A. Beate C." } }, { "id": "Rauer-H", "name": { "family": "Rauer", "given": "Heike" } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "A detailed pathway analysis of the chemical reaction system generating the Martian vertical ozone profile", "ispublished": "pub", "full_text_status": "restricted", "keywords": "Atmospheres; chemistry; composition; Mars; atmosphere; Photochemistry", "note": "\u00a9 2016 Elsevier Inc. \n\nReceived date: 7 December 2015; Revised date: 15 November 2016; Accepted date: 5 December 2016; Available online: 9 December 2016. \n\nThis research has been partly supported by the Helmholtz Association through the research alliance \"Planetary Evolution and Life\". This work was partially funded by grant AyA 2012-32237 awarded by the Spanish Ministerio de Economia y Competitividad. The authors would like to thank Run-Lie Shia and Dickens Saint-Hilaire for their contributions to the discussion.", "abstract": "Atmospheric chemical composition is crucial in determining a planet's atmospheric structure, stability, and evolution. Attaining a quantitative understanding of the essential chemical mechanisms governing atmospheric composition is nontrivial due to complex interactions between chemical species. Trace species, for example, can participate in catalytic cycles \u2013 affecting the abundance of major and other trace gas species. Specifically, for Mars, such cycles dictate the abundance of its primary atmospheric constituent, carbon dioxide (CO_2), but also for one of its trace gases, ozone (O_3). The identification of chemical pathways/cycles by hand is extremely demanding; hence, the application of numerical methods, such as the Pathway Analysis Program (PAP), is crucial to analyze and quantitatively exemplify chemical reaction networks. Here, we carry out the first automated quantitative chemical pathway analysis of Mars' atmosphere with respect to O_3. PAP was applied to JPL/Caltech's 1-D updated photochemical Mars model's output data. We determine all significant chemical pathways and their contribution to O_3 production and consumption (up to 80\u2009km) in order to investigate the mechanisms causing the characteristic shape of the O_3 volume mixing ratio profile, i.e. a ground layer maximum and an ozone layer at \u223c 50\u2009km. These pathways explain why an O_3 layer is present, why it is located at that particular altitude and what the different processes forming the near-surface and middle atmosphere O_3 maxima are. Furthermore, we show that the Martian atmosphere can be divided into two chemically distinct regions according to the O(^3P):O_3 ratio. In the lower region (below approximately 24\u2009km altitude) O_3 is the most abundant O_\nx ( = O_3 + O(^3P)) species. In the upper region (above approximately 24\u2009km altitude), where the O_3 layer is located, O(^3P) is the most abundant O_x species. Earlier results concerning the formation of O_3 on Mars can now be explained with the help of chemical pathways leading to a better understanding of the vertical O_3 profile.", "date": "2017-07-15", "date_type": "published", "publication": "Icarus", "volume": "291", "publisher": "Elsevier", "pagerange": "192-202", "id_number": "CaltechAUTHORS:20161216-142604512", "issn": "0019-1035", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20161216-142604512", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Helmholtz Association" }, { "agency": "Ministerio de Econom\u00eda y Competitividad (MINECO)", "grant_number": "AyA 2012-32237" } ] }, "local_group": { "items": [ { "id": "Astronomy-Department" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/j.icarus.2016.12.012", "resource_type": "article", "pub_year": "2017", "author_list": "Stock, Joachim W.; Blaszczak-Boxe, Christopher S.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/rmqrc-bkm60", "eprint_id": 78082, "eprint_status": "archive", "datestamp": "2023-08-19 03:36:46", "lastmod": "2023-10-25 23:44:16", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Su-Hui", "name": { "family": "Su", "given": "Hui" }, "orcid": "0000-0003-1265-9702" }, { "id": "Jiang-Jonathan-H", "name": { "family": "Jiang", "given": "Jonathan H." }, "orcid": "0000-0002-5929-8951" }, { "id": "Neelin-J-David", "name": { "family": "Neelin", "given": "J. David" }, "orcid": "0000-0001-9414-9962" }, { "id": "Shen-T-Janicee", "name": { "family": "Shen", "given": "T. Janice" } }, { "id": "Zhai-Chengxing", "name": { "family": "Zhai", "given": "Chengxing" }, "orcid": "0000-0002-0291-4522" }, { "id": "Yue-Qing", "name": { "family": "Yue", "given": "Qing" } }, { "id": "Wang-Zhien", "name": { "family": "Wang", "given": "Zhien" } }, { "id": "Huang-Lei", "name": { "family": "Huang", "given": "Lei" }, "orcid": "0000-0002-4941-7814" }, { "id": "Choi-Yong-Sang", "name": { "family": "Choi", "given": "Yong-Sang" } }, { "id": "Stephens-Graeme-L", "name": { "family": "Stephens", "given": "Graeme L." }, "orcid": "0000-0002-9860-0287" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Tightening of tropical ascent and high clouds key to precipitation change in a warmer climate", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2017 The Author(s). This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/. \n\nReceived: 20 June 2016; Accepted: 27 April 2017; Published online: 07 June 2017. \n\nWe acknowledge the funding support from NASA NEWS, AST, MAP, NDOA and NSF. We greatly appreciate Michael Wong in making the schematic figure. We thank Shang-min Long, Ryan Stanfield and Jung-Min Park for assistance in some parts of the auxicillary analyses. We thank Drs Brian Soden and Karen Shell for providing the radiative kernel functions. We appreciate helpful discussions with Drs Chris Bretherton, Anthony DeAngelis, Feifei Jin, Xin Qu and Shang-Ping Xie. We thank three anonymous reviewers for insightful suggestions. This work was performed at Jet Propulsion Laboratory, California Institute of Technology, under contract with NASA. \n\nAuthor Contributions: H.S. designed the analysis and wrote the paper. H.S., J.H.J., T.J.S. and C.Z. analysed the CMIP5 model simulations and observations. Q.Y. analysed the MODIS cloud fraction data. Z.W. and L.H. analysed the joint CloudSat/CALIPSO cloud fraction retrieval. Y.-S.C. analysed the combined ERBE-CERES data. J.D.N., G.L.S. and Y.L.Y. provided suggestions for the analysis and comments on the manuscript. Everyone edited the manuscript. \n\nThe authors declare no competing financial interests.\n\nPublished - ncomms15771.pdf
Supplemental Material - ncomms15771-s1.pdf
Supplemental Material - ncomms15771-s2.pdf
", "abstract": "The change of global-mean precipitation under global warming and interannual variability is predominantly controlled by the change of atmospheric longwave radiative cooling. Here we show that tightening of the ascending branch of the Hadley Circulation coupled with a decrease in tropical high cloud fraction is key in modulating precipitation response to surface warming. The magnitude of high cloud shrinkage is a primary contributor to the intermodel spread in the changes of tropical-mean outgoing longwave radiation (OLR) and global-mean precipitation per unit surface warming (dP/dT_s) for both interannual variability and global warming. Compared to observations, most Coupled Model Inter-comparison Project Phase 5 models underestimate the rates of interannual tropical-mean dOLR/dT_s and global-mean dP/dT_s, consistent with the muted tropical high cloud shrinkage. We find that the five models that agree with the observation-based interannual dP/dT_s all predict dP/dT_s under global warming higher than the ensemble mean dP/dT_s from the \u223c20 models analysed in this study.", "date": "2017-06-07", "date_type": "published", "publication": "Nature Communications", "volume": "8", "publisher": "Nature Publishing Group", "pagerange": "Art. No. 15771", "id_number": "CaltechAUTHORS:20170612-073313585", "issn": "2041-1723", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170612-073313585", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA/JPL/Caltech" }, { "agency": "NSF" } ] }, "local_group": { "items": [ { "id": "Astronomy-Department" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1038/ncomms15771", "pmcid": "PMC5467267", "primary_object": { "basename": "ncomms15771-s1.pdf", "url": "https://authors.library.caltech.edu/records/rmqrc-bkm60/files/ncomms15771-s1.pdf" }, "related_objects": [ { "basename": "ncomms15771-s2.pdf", "url": "https://authors.library.caltech.edu/records/rmqrc-bkm60/files/ncomms15771-s2.pdf" }, { "basename": "ncomms15771.pdf", "url": "https://authors.library.caltech.edu/records/rmqrc-bkm60/files/ncomms15771.pdf" } ], "resource_type": "article", "pub_year": "2017", "author_list": "Su, Hui; Jiang, Jonathan H.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/da5ty-gq866", "eprint_id": 71138, "eprint_status": "archive", "datestamp": "2023-08-21 20:58:25", "lastmod": "2023-10-23 15:22:04", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Gao-Peter", "name": { "family": "Gao", "given": "Peter" }, "orcid": "0000-0002-8518-9601" }, { "id": "Fan-Siteng", "name": { "family": "Fan", "given": "Siteng" }, "orcid": "0000-0002-3041-4680" }, { "id": "Wong-Michael-L", "name": { "family": "Wong", "given": "Michael L." } }, { "id": "Liang-Mao-Chang", "name": { "family": "Liang", "given": "Mao-Chang" }, "orcid": "0000-0002-5294-9344" }, { "id": "Shia-Run-Lie", "name": { "family": "Shia", "given": "Run-Lie" }, "orcid": "0000-0003-1911-3120" }, { "id": "Kammer-J-A", "name": { "family": "Kammer", "given": "Joshua A." }, "orcid": "0000-0002-3441-3757" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Summers-M-E", "name": { "family": "Summers", "given": "Michael E." } }, { "id": "Gladstone-G-R", "name": { "family": "Gladstone", "given": "G. Randall" } }, { "id": "Young-L-A", "name": { "family": "Young", "given": "Leslie A." } }, { "id": "Olkin-C-B", "name": { "family": "Olkin", "given": "Catherine B." }, "orcid": "0000-0002-5846-716X" }, { "id": "Ennico-K", "name": { "family": "Ennico", "given": "Kimberly" }, "orcid": "0000-0002-8847-8492" }, { "id": "Weaver-H-A", "name": { "family": "Weaver", "given": "Harold A." }, "orcid": "0000-0003-0951-7762" }, { "id": "Stern-S-A", "name": { "family": "Stern", "given": "S. Alan" } } ] }, "title": "Constraints on the microphysics of Pluto's photochemical haze from New Horizons observations", "ispublished": "pub", "full_text_status": "public", "keywords": "Abundances, atmospheres; Atmospheres, chemistry; Atmospheres, composition; Pluto; Pluto, atmosphere", "note": "\u00a9 2016 Elsevier Inc. \n\nReceived 16 May 2016; Revised 27 August 2016; Accepted 20 September 2016; Available online 22 September 2016. \n\nThis research was supported in part by a grant from the New Horizons Mission. YLY and RLS were supported in part by the Cassini UVIS program via NASA Grant JPL.1459109, NASA NNX09AB72G grant to the California Institute of Technology. PG was supported in part by an RTD grant from JPL.\n\nSubmitted - 1610.01679.pdf
", "abstract": "The New Horizons flyby of Pluto confirmed the existence of hazes in its atmosphere. Observations of a large high- to low- phase brightness ratio, combined with the blue color of the haze (indicative of Rayleigh scattering), suggest that the haze particles are fractal aggregates, perhaps analogous to the photochemical hazes on Titan. Therefore, studying the Pluto hazes can shed light on the similarities and differences between the Pluto and Titan atmospheres. We model the haze distribution using the Community Aerosol and Radiation Model for Atmospheres assuming that the distribution is shaped by downward transport and coagulation of particles originating from photochemistry. Hazes composed of both purely spherical and purely fractal aggregate particles are considered. General agreement between model results and solar occultation observations is obtained with aggregate particles when the downward mass flux of photochemical products is equal to the column-integrated methane destruction rate \u223c1.2 \u00d7 10^(\u221214) g cm^(\u22122) s^(\u22121), while for spherical particles the mass flux must be 2\u20133 times greater. This flux is nearly identical to the haze production flux of Titan previously obtained by comparing microphysical model results to Cassini observations. The aggregate particle radius is sensitive to particle charging effects, and a particle charge to radius ratio of 30 e \u2212 /\u00b5m is necessary to produce \u223c0.1\u20130.2 \u00b5m aggregates near Pluto's surface, in accordance with forward scattering measurements. Such a particle charge to radius ratio is 2\u20134 times higher than those previously obtained for Titan. Hazes composed of spheres with the same particle charge to radius ratio have particles that are 4 times smaller at Pluto's surface. These results further suggest that the haze particles are fractal aggregates. We also consider the effect of condensation of HCN, C_2H_2, C_2H_4, and C_2H_6 on the haze particles, which may play an important role in shaping their altitude and size distributions.", "date": "2017-05-01", "date_type": "published", "publication": "Icarus", "volume": "287", "publisher": "Elsevier", "pagerange": "116-123", "id_number": "CaltechAUTHORS:20161017-082804466", "issn": "0019-1035", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20161017-082804466", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "JPL.1459109" }, { "agency": "NASA", "grant_number": "NNX09AB72G" }, { "agency": "JPL Research and Technology Development Fund" } ] }, "local_group": { "items": [ { "id": "Astronomy-Department" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "corp_creators": { "items": [ "New Horizons Science Team" ] }, "doi": "10.1016/j.icarus.2016.09.030", "primary_object": { "basename": "1610.01679.pdf", "url": "https://authors.library.caltech.edu/records/da5ty-gq866/files/1610.01679.pdf" }, "resource_type": "article", "pub_year": "2017", "author_list": "Gao, Peter; Fan, Siteng; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/bwzpf-qgv27", "eprint_id": 71376, "eprint_status": "archive", "datestamp": "2023-08-21 20:58:34", "lastmod": "2023-10-23 15:41:40", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Wong-Michael-L", "name": { "family": "Wong", "given": "Michael L." } }, { "id": "Fan-Siteng", "name": { "family": "Fan", "given": "Siteng" }, "orcid": "0000-0002-3041-4680" }, { "id": "Gao-Peter", "name": { "family": "Gao", "given": "Peter" }, "orcid": "0000-0002-8518-9601" }, { "id": "Liang-Mao-Chang", "name": { "family": "Liang", "given": "Mao-Chang" }, "orcid": "0000-0002-5294-9344" }, { "id": "Shia-Run-Lie", "name": { "family": "Shia", "given": "Run-Lie" }, "orcid": "0000-0003-1911-3120" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Kammer-J-A", "name": { "family": "Kammer", "given": "Joshua A." }, "orcid": "0000-0002-3441-3757" }, { "id": "Summers-M-E", "name": { "family": "Summers", "given": "Michael E." } }, { "id": "Gladstone-G-R", "name": { "family": "Gladstone", "given": "G. Randall" } }, { "id": "Young-L-A", "name": { "family": "Young", "given": "Leslie A." } }, { "id": "Olkin-C-B", "name": { "family": "Olkin", "given": "Catherine B." }, "orcid": "0000-0002-5846-716X" }, { "id": "Ennico-K", "name": { "family": "Ennico", "given": "Kimberly" }, "orcid": "0000-0002-8847-8492" }, { "id": "Weaver-H-A", "name": { "family": "Weaver", "given": "Harold A." }, "orcid": "0000-0003-0951-7762" }, { "id": "Stern-S-A", "name": { "family": "Stern", "given": "S. Alan" } } ] }, "title": "The photochemistry of Pluto's atmosphere as illuminated by New Horizons", "ispublished": "pub", "full_text_status": "restricted", "keywords": "Pluto, atmosphere; Atmospheres, composition; Atmospheres, chemistry; Photochemistry", "note": "\u00a9 2016 Elsevier Inc. \n\nReceived 16 May 2016, Revised 27 August 2016, Accepted 17 September 2016, Available online 29 September 2016. \n\nThis research was supported in part by a grant from the New Horizons mission. YLY and RLS were supported in part by the Cassini UVIS program via NASA Grant JPL.1459109, NASA NNX09AB72G grant to the California Institute of Technology. PG was supported in part by an RTD grant from JPL. MLW is grateful to Theater Arts at Caltech as a source of personal motivation by giving him the chance to portray Clyde Tombaugh in Planet Between the Stars during the course of this project.", "abstract": "New Horizons has granted us an unprecedented glimpse at the structure and composition of Pluto's atmosphere, which is comprised mostly of N_2 with trace amounts of CH_4, CO, and the photochemical products thereof. Through photochemistry, higher-order hydrocarbons are generated, coagulating into aerosols and resulting in global haze layers. Here we present a state-of-the-art photochemical model for Pluto's atmosphere to explain the abundance profiles of CH_4, C_2H_2, C_2H_4, and C_2H_6, the total column density of HCN, and to predict the abundance profiles of oxygen-bearing species. The CH_4 profile can be best matched by taking a constant-with-altitude eddy diffusion coefficient K_(zz) profile of 1\u2009\u00d7\u200910^3 cm^2 s^(\u20131) and a fixed CH_4 surface mixing ratio of 4\u2009\u00d7\u200910^(\u20133). Condensation is key to fitting the C_2 hydrocarbon profiles. We find that C_2H_4 must have a much lower saturation vapor pressure than predicted by extrapolations of laboratory measurements to Pluto temperatures. We also find best-fit values for the sticking coefficients of C_2H_2, C_2H_4, C_2H_6, and HCN. The top three precipitating species are C_2H_2, C_2H_4, and C_2H_6, with precipitation rates of 179, 95, and 62 g cm^(\u20132) s^(\u20131), respectively.", "date": "2017-05-01", "date_type": "published", "publication": "Icarus", "volume": "287", "publisher": "Elsevier", "pagerange": "110-115", "id_number": "CaltechAUTHORS:20161024-102551698", "issn": "0019-1035", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20161024-102551698", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "JPL.1459109" }, { "agency": "NASA", "grant_number": "NNX09AB72G" }, { "agency": "JPL Research and Technology Development Fund" } ] }, "local_group": { "items": [ { "id": "Astronomy-Department" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "corp_creators": { "items": [ "New Horizons Science Team" ] }, "doi": "10.1016/j.icarus.2016.09.028", "resource_type": "article", "pub_year": "2017", "author_list": "Wong, Michael L.; Fan, Siteng; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/w4m14-4z521", "eprint_id": 91258, "eprint_status": "archive", "datestamp": "2023-08-22 19:48:58", "lastmod": "2023-10-19 22:20:52", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Su-Zhan", "name": { "family": "Su", "given": "Zhan" }, "orcid": "0000-0002-2699-431X" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Shia-Run-Lie", "name": { "family": "Shia", "given": "Run-Lie" }, "orcid": "0000-0003-1911-3120" }, { "id": "Miller-C-E", "name": { "family": "Miller", "given": "Charles E." }, "orcid": "0000-0002-9380-4838" } ] }, "title": "Assessing accuracy and precision for space-based measurements of carbon dioxide: An associated statistical methodology revisited", "ispublished": "pub", "full_text_status": "public", "keywords": "statistical methodology; space\u2010based measurement", "note": "\u00a92017. The Authors. This is an open access article under the terms of the Creative Commons Attribution\u2010NonCommercial\u2010NoDerivs License, which permits use and distribution in any medium, provided the original work is properly cited, the use is non\u2010commercial and no modifications or adaptations are made. \n\nReceived 10 OCT 2016. Accepted 16 FEB 2017. Accepted article online 24 FEB 2017. Published online 29 MAR 2017. \n\nWe gratefully acknowledge the helpful comments/suggestions from three anonymous reviewers and the Editor. We thank Paul O. Wennberg, John Worden, Vijay Natraj, Michael Line, King\u2010Fai Li for useful comments/discussions, and Le Kuai for providing the model used in this study. This research is supported in part by the Orbiting Carbon Observatory (OCO\u20102) project, a NASA Earth System Science Pathfinder (ESSP) mission, and JPL P765982 grant to the California Institute of Technology.\n\nPublished - Su_et_al-2017-Earth_and_Space_Science.pdf
", "abstract": "Analyzing retrieval accuracy and precision is an important element of space\u2010based CO_2 retrievals. However, this error analysis is sometimes challenging to perform rigorously because of the subtlety of Multivariate Statistics. To help address this issue, we revisit some fundamentals of Multivariate Statistics that help reveal the statistical essence of the associated error analysis. We show that the related statistical methodology is useful for revealing the intrinsic discrepancy and relation between the retrieval error for a nonzero\u2010variate CO_2 state and that for a zero\u2010variate one. Our study suggests that the two scenarios essentially yield the same\u2010magnitude accuracy, while the latter scenario yields a better precision than the former. We also use this methodology to obtain a rigorous framework systematically and explore a broadly used approximate framework for analyzing CO_2 retrieval errors. The approximate framework introduces errors due to an essential, but often forgotten, fact that a priori climatology in reality is never equal to the true state. Due to the nature of the problem considered, realistic numerical simulations that produce synthetic spectra may be more appropriate than remote sensing data for our specific exploration. As highlighted in our retrieval simulations, utilizing the approximate framework may not be universally satisfactory in assessing the accuracy and precision of X_(co_2) retrievals (with errors up to 0.17\u20130.28\u2009ppm and 1.4\u20131.7\u2009ppm, respectively, at SNR\u2009=\u2009400). In situ measurements of CO_2 are needed to further our understanding of this issue and related implications.", "date": "2017-03", "date_type": "published", "publication": "Earth and Space Science", "volume": "4", "number": "3", "publisher": "American Geophysical Union", "pagerange": "147-161", "id_number": "CaltechAUTHORS:20181127-160003519", "issn": "2333-5084", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20181127-160003519", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "JPL", "grant_number": "P765982" }, { "agency": "Orbiting Carbon Observatory (OCO-2)" } ] }, "local_group": { "items": [ { "id": "Astronomy-Department" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1002/2016ea000228", "primary_object": { "basename": "Su_et_al-2017-Earth_and_Space_Science.pdf", "url": "https://authors.library.caltech.edu/records/w4m14-4z521/files/Su_et_al-2017-Earth_and_Space_Science.pdf" }, "resource_type": "article", "pub_year": "2017", "author_list": "Su, Zhan; Yung, Yuk L.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/m986k-1bs25", "eprint_id": 75555, "eprint_status": "archive", "datestamp": "2023-08-19 01:35:03", "lastmod": "2023-10-20 23:27:22", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Zeng-Zhao-Cheng", "name": { "family": "Zeng", "given": "Zhao-Cheng" }, "orcid": "0000-0002-0008-6508" }, { "id": "Zhang-Qiong", "name": { "family": "Zhang", "given": "Qiong" }, "orcid": "0000-0002-8762-0557" }, { "id": "Natraj-V", "name": { "family": "Natraj", "given": "Vijay" }, "orcid": "0000-0003-3154-9429" }, { "id": "Margolis-J-S", "name": { "family": "Margolis", "given": "Jack S." } }, { "id": "Shia-Run-Lie", "name": { "family": "Shia", "given": "Run-Lie" }, "orcid": "0000-0003-1911-3120" }, { "id": "Newman-S", "name": { "family": "Newman", "given": "Sally" }, "orcid": "0000-0003-0710-995X" }, { "id": "Fu-Dejian", "name": { "family": "Fu", "given": "Dejian" } }, { "id": "Pongetti-T-J", "name": { "family": "Pongetti", "given": "Thomas J." }, "orcid": "0000-0001-9465-0853" }, { "id": "Wong-Kam-Weng", "name": { "family": "Wong", "given": "Kam W." } }, { "id": "Sander-S-P", "name": { "family": "Sander", "given": "Stanley P." }, "orcid": "0000-0003-1424-3620" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Aerosol scattering effects on water vapor retrievals over the Los Angeles Basin", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 Author(s) 2017. This work is distributed under the Creative Commons Attribution 3.0 License. \n\nReceived: 08 Jun 2016 \u2013 Discussion started: 20 Jun 2016. Revised: 27 Jan 2017 \u2013 Accepted: 27 Jan 2017 \u2013 Published: 17 Feb 2017. \n\nWe thank M. Gunson and A. Eldering for stimulating discussions and support, and M. Gerstell for proofreading the manuscript. Part of the research in this study was performed at the Jet Propulsion Laboratory (JPL), California Institute of Technology (Caltech), under a contract with the National Aeronautics and Space Administration (NASA). Support from the Caltech KISS Megacity project, the NIST GHG and Climate Science Program and NASA's Carbon Cycle Science Program through the JPL is gratefully acknowledged. Zhao-Cheng Zeng was supported by a postgraduate studentship for overseas academic exchange from the Chinese University of Hong Kong. We thank Jochen Stutz and his staff for their effort in establishing and maintaining the AERONET Caltech site. We also thank the anonymous reviewers whose comments helped improve the paper significantly. \n\nData availability: The AERONET data for this paper can be downloaded online (http://aeronet.gsfc.nasa.gov); CLARS-FTS data are available from the authors upon request. \n\nThe Supplement related to this article is available online at doi:10.5194/acp-17-2495-2017-supplement. The copyright of individual parts of the supplement might differ from the CC-BY 3.0 licence. \n\nThe authors declare that they have no conflict of interest.\n\nPublished - acp-17-2495-2017.pdf
Supplemental Material - acp-17-2495-2017-supplement.pdf
", "abstract": "In this study, we propose a novel approach to describe the scattering effects of atmospheric aerosols in a complex urban environment using water vapor (H_2O) slant column measurements in the near infrared. This approach is demonstrated using measurements from the California Laboratory for Atmospheric Remote Sensing Fourier Transform Spectrometer on the top of Mt. Wilson, California, and a two-stream-exact single scattering (2S-ESS) radiative transfer (RT) model. From the spectral measurements, we retrieve H_2O slant column density (SCD) using 15 different absorption bands between 4000 and 8000\u202fcm^(\u22121). Due to the wavelength dependence of aerosol scattering, large variations in H_2O SCD retrievals are observed as a function of wavelength. Moreover, the variations are found to be correlated with aerosol optical depths (AODs) measured at the AERONET-Caltech station. Simulation results from the RT model reproduce this correlation and show that the aerosol scattering effect is the primary contributor to the variations in the wavelength dependence of the H_2O SCD retrievals. A significant linear correlation is also found between variations in H_2O SCD retrievals from different bands and corresponding AOD data; this correlation is associated with the asymmetry parameter, which is a first-order measure of the aerosol scattering phase function. The evidence from both measurements and simulations suggests that wavelength-dependent aerosol scattering effects can be derived using H_2O retrievals from multiple bands. This understanding of aerosol scattering effects on H_2O retrievals suggests a promising way to quantify the effect of aerosol scattering on greenhouse gas retrievals and could potentially contribute towards reducing biases in greenhouse gas retrievals from space.", "date": "2017-02-17", "date_type": "published", "publication": "Atmospheric Chemistry and Physics", "volume": "17", "number": "4", "publisher": "European Geosciences Union", "pagerange": "2495-2508", "id_number": "CaltechAUTHORS:20170330-153453156", "issn": "1680-7324", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170330-153453156", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA/JPL/Caltech" }, { "agency": "Keck Institute for Space Studies (KISS)" }, { "agency": "National Institute of Standards and Technology (NIST)" }, { "agency": "Chinese University of Hong Kong" } ] }, "local_group": { "items": [ { "id": "Keck-Institute-for-Space-Studies" }, { "id": "Astronomy-Department" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/acp-17-2495-2017", "primary_object": { "basename": "acp-17-2495-2017-supplement.pdf", "url": "https://authors.library.caltech.edu/records/m986k-1bs25/files/acp-17-2495-2017-supplement.pdf" }, "related_objects": [ { "basename": "acp-17-2495-2017.pdf", "url": "https://authors.library.caltech.edu/records/m986k-1bs25/files/acp-17-2495-2017.pdf" } ], "resource_type": "article", "pub_year": "2017", "author_list": "Zeng, Zhao-Cheng; Zhang, Qiong; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/v7syt-cgz65", "eprint_id": 71741, "eprint_status": "archive", "datestamp": "2023-08-22 19:28:29", "lastmod": "2023-10-23 17:02:03", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Kim-Sang-Joon", "name": { "family": "Kim", "given": "Sang Joon" } }, { "id": "Geballe-T-R", "name": { "family": "Geballe", "given": "Thomas R." } }, { "id": "Greathouse-T-K", "name": { "family": "Greathouse", "given": "Thomas K." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Miller-S", "name": { "family": "Miller", "given": "Steve" } }, { "id": "Orton-G-S", "name": { "family": "Orton", "given": "G. S." }, "orcid": "0000-0001-7871-2823" }, { "id": "Minh-Y-C", "name": { "family": "Minh", "given": "Y. C." } } ] }, "title": "Temperatures and CH_4 mixing ratios near the homopause of the 8\u00b5m north polar hot spot of Jupiter", "ispublished": "pub", "full_text_status": "restricted", "keywords": "Jupiter; Atmosphere; Aurora; Infrared; Spectroscopy", "note": "\u00a9 2016 Elsevier Inc. \n\nAvailable online 13 September 2016. \n\nSJK acknowledges support from the Space Core Technology program through NRF funded by the Ministry of Education, Science and Technology, and from KASI under the R&D program supervised by the Ministry of Science, ICT and Future Planning. Support for GSO was provided, in part, by an award from NASA to the Jet Propulsion Laboratory, California Institute of Technology. The research is based in part on observations obtained at the Gemini Observatory, which is operated by the Association of Universities for Research in Astronomy, Inc., under a cooperative agreement with the NSF on behalf of the Gemini partnership: the National Science Foundation (United States), the National Research Council (Canada), CONICYT (Chile), Ministerio de Ciencia, Tecnolog\u00eda e Innovaci\u00f3n Productiva (Argentina), and Minist\u00e9rio da Ci\u00eancia, Tecnologia e Inova\u00e7\u00e3o (Brazil).", "abstract": "We have derived homopause temperatures of 180\u2013250 K for the 8-\u00b5m north-polar hot spot (8NPHS) of Jupiter by fitting CH_4 emission models to 3 and 8 \u00b5m spectra of the 8NPHS obtained 24 days apart in 2013. From the fits, we find that CH_4 mixing ratios at the 8NPHS are consistent with those reported by Kim et al. (2014) in equatorial regions. We propose possible mechanisms to account for the temperature of the 8NPHS homopause, which is relatively cool compared with the temperatures of other auroral regions, including locally-fixed and transient but energetic auroral particle precipitation.", "date": "2017-01-01", "date_type": "published", "publication": "Icarus", "volume": "281", "publisher": "Elsevier", "pagerange": "281-285", "id_number": "CaltechAUTHORS:20161104-101502736", "issn": "0019-1035", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20161104-101502736", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "National Research Foundation of Korea" }, { "agency": "Ministry of Science, ICT and Future Planning (Korea)" }, { "agency": "NASA/JPL/Caltech" }, { "agency": "NSF" }, { "agency": "National Research Council of Canada" }, { "agency": "Comisi\u00f3n Nacional de Investigaci\u00f3n Cient\u00edfica y Tecnol\u00f3gica (CONICYT)" }, { "agency": "Ministerio de Ciencia, Tecnolog\u00eda e Innovaci\u00f3n Productiva" }, { "agency": "Minist\u00e9rio da Ci\u00eancia, Tecnologia e Inova\u00e7\u00e3o" }, { "agency": "Korea Astronomy and Space Science Institute (KASI)" } ] }, "local_group": { "items": [ { "id": "Astronomy-Department" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/j.icarus.2016.09.017", "resource_type": "article", "pub_year": "2017", "author_list": "Kim, Sang Joon; Geballe, Thomas R.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/j8q36-anh16", "eprint_id": 72566, "eprint_status": "archive", "datestamp": "2023-08-20 14:16:37", "lastmod": "2023-10-23 22:43:51", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Wong-Clare-K", "name": { "family": "Wong", "given": "Clare K." } }, { "id": "Pongetti-T-J", "name": { "family": "Pongetti", "given": "Thomas J." }, "orcid": "0000-0001-9465-0853" }, { "id": "Oda-T", "name": { "family": "Oda", "given": "Tom" } }, { "id": "Rao-Preeti", "name": { "family": "Rao", "given": "Preeti" }, "orcid": "0000-0002-5549-0583" }, { "id": "Gurney-K-R", "name": { "family": "Gurney", "given": "Kevin R." }, "orcid": "0000-0001-9218-7164" }, { "id": "Newman-S", "name": { "family": "Newman", "given": "Sally" }, "orcid": "0000-0003-0710-995X" }, { "id": "Duren-R-M", "name": { "family": "Duren", "given": "Riley M." }, "orcid": "0000-0003-4723-5280" }, { "id": "Miller-C-E", "name": { "family": "Miller", "given": "Charles E." }, "orcid": "0000-0002-9380-4838" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Sander-S-P", "name": { "family": "Sander", "given": "Stanley P." }, "orcid": "0000-0003-1424-3620" } ] }, "title": "Monthly trends of methane emissions in Los Angeles from 2011 to 2015 inferred by CLARS-FTS observations", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2016 Author(s). This work is distributed under the Creative Commons Attribution 3.0 License. \n\nReceived: 16 Mar 2016 \u2013 Published in Atmos. Chem. Phys. Discuss.: 29 Apr 2016; Revised: 06 Sep 2016 \u2013 Accepted: 10 Sep 2016 \u2013 Published: 26 Oct 2016. \n\nThe research in this study was performed at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration. Clare K. Wong thanks the California Air Resources Board, NIST GHG and Climate Science Program, and the W. M. Keck Institute for Space Studies for support. The authors would like to acknowledge our colleagues at JPL and California Institute of Technology, and Risa Patarasuk at Arizona State University for helpful comments and suggestions.\n\nPublished - acp-16-13121-2016.pdf
Supplemental Material - acp-16-13121-2016-supplement.pdf
", "abstract": "This paper presents an analysis of methane emissions from the Los Angeles Basin at monthly timescales across a 4-year time period \u2013 from September 2011 to August 2015. Using observations acquired by a ground-based near-infrared remote sensing instrument on Mount Wilson, California, combined with atmospheric CH_4\u2013CO_2 tracer\u2013tracer correlations, we observed \u221218 to +22\u202f% monthly variability in CH_4\u202f:\u202fCO_2 from the annual mean in the Los Angeles Basin. Top-down estimates of methane emissions for the basin also exhibit significant monthly variability (\u221219 to +31\u202f% from annual mean and a maximum month-to-month change of 47\u202f%). During this period, methane emissions consistently peaked in the late summer/early fall and winter. The estimated annual methane emissions did not show a statistically significant trend over the 2011 to 2015 time period.", "date": "2016-10-26", "date_type": "published", "publication": "Atmospheric Chemistry and Physics", "volume": "16", "number": "20", "publisher": "European Geosciences Union", "pagerange": "13121-13130", "id_number": "CaltechAUTHORS:20161205-142301578", "issn": "1680-7324", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20161205-142301578", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA/JPL/Caltech" }, { "agency": "California Air Resources Board" }, { "agency": "National Institute of Standards and Technology (NIST)" }, { "agency": "Keck Institute for Space Studies (KISS)" } ] }, "local_group": { "items": [ { "id": "Keck-Institute-for-Space-Studies" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/acp-16-13121-2016", "primary_object": { "basename": "acp-16-13121-2016.pdf", "url": "https://authors.library.caltech.edu/records/j8q36-anh16/files/acp-16-13121-2016.pdf" }, "related_objects": [ { "basename": "acp-16-13121-2016-supplement.pdf", "url": "https://authors.library.caltech.edu/records/j8q36-anh16/files/acp-16-13121-2016-supplement.pdf" } ], "resource_type": "article", "pub_year": "2016", "author_list": "Wong, Clare K.; Pongetti, Thomas J.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/ny8w9-fqe58", "eprint_id": 70649, "eprint_status": "archive", "datestamp": "2023-08-22 18:50:40", "lastmod": "2023-10-20 23:17:58", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Willacy-K", "name": { "family": "Willacy", "given": "K." }, "orcid": "0000-0001-6124-5974" }, { "id": "Allen-M-A", "name": { "family": "Allen", "given": "M." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Y." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "A new astrobiological model of the atmosphere of Titan", "ispublished": "pub", "full_text_status": "public", "keywords": "planets and satellites: atmospheres; planets and satellites: composition; planets and satellites: individual (Titan)", "note": "\u00a9 2016 American Astronomical Society. \n\nReceived 2016 May 3; revised 2016 July 11; accepted 2016 July 15; published 2016 September 23. \n\nThis research was conducted at the Jet Propulsion Laboratory, California Institute of Technology under contract with the National Aeronautics and Space Administration. Support was provided by the NASA Astrobiology Institute/Titan as a Prebiotic Chemical System. Y.L.Y. was supported in part by the Cassini UVIS program via NASA grant JPL.1459109 to the California Institute of Technology. The authors thank Dr. Run-Lie Shia for his assistance with the KINETICS code and Dr. Panyotis Lavvas for providing the aerosol data used in these models. \n\nSoftware: KINETICS (Allen et al. 1981).\n\nPublished - apj_829_2_79.pdf
Submitted - 1607.04687v2.pdf
", "abstract": "We present results of an investigation into the formation of nitrogen-bearing molecules in the atmosphere of Titan. We extend a previous model to cover the region below the tropopause, so the new model treats the atmosphere from Titan's surface to an altitude of 1500 km. We consider the effects of condensation and sublimation using a continuous, numerically stable method. This is coupled with parameterized treatments of the sedimentation of the aerosols and their condensates, and the formation of haze particles. These processes affect the abundances of heavier species such as the nitrogen-bearing molecules, but have less effect on the abundances of lighter molecules. Removal of molecules to form aerosols also plays a role in determining the mixing ratios, particularly of HNC, HC_3N, and HCN. We find good agreement with the recently detected mixing ratios of C_2H_5CN, with condensation playing an important role in determining the abundance of this molecule below 500 km. Of particular interest is the chemistry of acrylonitrile (C_2H_3CN) which has been suggested by Stevenson et al. as a molecule that could form biological membranes in an oxygen-deficient environment. With the inclusion of haze formation, we find good agreement of our model predictions of acrylonitrile with the available observations.", "date": "2016-10-01", "date_type": "published", "publication": "Astrophysical Journal", "volume": "829", "number": "2", "publisher": "American Astronomical Society", "pagerange": "Art. No. 79", "id_number": "CaltechAUTHORS:20160928-154658017", "issn": "0004-637X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160928-154658017", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA/JPL/Caltech" }, { "agency": "NASA", "grant_number": "JPL.1459109" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.3847/0004-637X/829/2/79", "primary_object": { "basename": "1607.04687v2.pdf", "url": "https://authors.library.caltech.edu/records/ny8w9-fqe58/files/1607.04687v2.pdf" }, "related_objects": [ { "basename": "apj_829_2_79.pdf", "url": "https://authors.library.caltech.edu/records/ny8w9-fqe58/files/apj_829_2_79.pdf" } ], "resource_type": "article", "pub_year": "2016", "author_list": "Willacy, K.; Allen, M.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/qrdt6-zjv23", "eprint_id": 91256, "eprint_status": "archive", "datestamp": "2023-08-22 18:49:11", "lastmod": "2023-10-19 22:20:45", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Li-King-Fai", "name": { "family": "Li", "given": "King-Fai" }, "orcid": "0000-0003-0150-2910" }, { "id": "Zhang-Qiong", "name": { "family": "Zhang", "given": "Qiong" }, "orcid": "0000-0002-8762-0557" }, { "id": "Tung-Ka-Kit", "name": { "family": "Tung", "given": "Ka-Kit" }, "orcid": "0000-0001-8667-7167" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Resolving a long-standing model-observation discrepancy on ozone solar cycle response", "ispublished": "pub", "full_text_status": "public", "keywords": "orbital drifts; diurnal asymmetry; artificial decadal variability", "note": "\u00a92016. The Authors. This is an open access article under the terms of the Creative Commons Attribution\u2010NonCommercial\u2010NoDerivs License, which permits use and distribution in any medium, provided the original work is properly cited, the use is non\u2010commercial and no modifications or adaptations are made. \n\nReceived 27 JUL 2016. Accepted 3 OCT 2016. Accepted article online 8 OCT 2016. Published online 28 OCT 2016. \n\nK.F.L. thanks William J. Randel and Lucien Froidevaux for an illuminating discussion. We thank Irene Chen, Mimi Gerstell, Run\u2010Lie Shia, Sally Newman, Pushkar Kopparla, and Stanley P. Sander for reading the manuscript. K.F.L. has been partially supported by the NASA Jack Eddy Fellowship administrated by the University Corporation for Atmospheric Research. K.F.L. and K.K.T. have been supported by the NASA grant NNX14AR40G. Q.Z. and Y.L.Y. acknowledge partial support by NASA's LWS program via grant NNX16AK63G to the California Institute of Technology. The GOZCARDS data were obtained from https://gozcards.jpl.nasa.gov/. The SAGE\u2010corrected SBUV data can be obtained from ftp://es\u2010ee.tor.ec.gc.ca/pub/SAGE_corrected_SBUV/. The 10.7\u2009cm solar radio flux was obtained from http://www.spaceweather.ca/. The stratospheric zonal winds for deriving the two QBO indices were obtained from http://www.geo.fu\u2010berlin.de/en/met/ag/strat/produkte/qbo/qbo.dat. The Multivariate ENSO index was obtained from http://www.esrl.noaa.gov/psd/enso/mei.ext. The stratospheric aerosol optical thickness at 550\u2009nm was obtained from http://data.giss.nasa.gov/modelforce/strataer/. The SORCE solar spectral data can be obtained from http://lasp.colorado.edu/home/sorce/data/.\n\nPublished - Li_et_al-2016-Earth_and_Space_Science.pdf
", "abstract": "To have the capability for long\u2010term prediction of stratospheric ozone (O_3), chemistry\u2010climate models have often been tested against observations on decadal timescales. A model\u2010observation discrepancy in the tropical O_3 response to the 11\u2009year solar cycle, first noted in 1993, persists for more than 20\u2009years: While standard photochemical models predict a single\u2010peak response in the stratosphere, satellite observations show an unexpected double\u2010peak structure. Such discrepancy has led to the question of whether the current standard O_3 photochemistry is deficient. Various studies have explored uncertainties in photochemistry and dynamics but there has not been compelling evidence of model biases. Here we suggest that decadal satellite orbital drifts relative to the diurnal cycle could be the primary cause of the discrepancy. We show that the double\u2010peak structure can be reproduced by adding the A.M./P.M. diurnal difference to the single\u2010peak response predicted by the standard photochemistry. Thus we argue that the standard photochemistry is consistent with the observed solar cycle modulation in stratospheric O_3.", "date": "2016-10", "date_type": "published", "publication": "Earth and Space Science", "volume": "3", "number": "10", "publisher": "American Geophysical Union", "pagerange": "431-440", "id_number": "CaltechAUTHORS:20181127-160003306", "issn": "2333-5084", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20181127-160003306", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "University Corporation for Atmospheric Research" }, { "agency": "NASA", "grant_number": "NNX14AR40G" }, { "agency": "NASA", "grant_number": "NNX16AK63G" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1002/2016ea000199", "primary_object": { "basename": "Li_et_al-2016-Earth_and_Space_Science.pdf", "url": "https://authors.library.caltech.edu/records/qrdt6-zjv23/files/Li_et_al-2016-Earth_and_Space_Science.pdf" }, "resource_type": "article", "pub_year": "2016", "author_list": "Li, King-Fai; Zhang, Qiong; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/jp6c1-n2g81", "eprint_id": 70402, "eprint_status": "archive", "datestamp": "2023-08-22 18:46:32", "lastmod": "2024-02-02 21:05:57", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Ehlmann-B-L", "name": { "family": "Ehlmann", "given": "B. L." }, "orcid": "0000-0002-2745-3240" }, { "id": "Anderson-F-S", "name": { "family": "Anderson", "given": "F. S." } }, { "id": "Andrews-Hanna-J-C", "name": { "family": "Andrews-Hanna", "given": "J." } }, { "id": "Catling-D-C", "name": { "family": "Catling", "given": "D. C." } }, { "id": "Christensen-P-R", "name": { "family": "Christensen", "given": "P. R." } }, { "id": "Cohen-B-A", "name": { "family": "Cohen", "given": "B. A." }, "orcid": "0000-0001-5896-5903" }, { "id": "Dressing-C-D", "name": { "family": "Dressing", "given": "C. D." }, "orcid": "0000-0001-8189-0233" }, { "id": "Edwards-C-S", "name": { "family": "Edwards", "given": "C. S." } }, { "id": "Elkins-Tanton-L-T", "name": { "family": "Elkins-Tanton", "given": "L. T." } }, { "id": "Farley-K-A", "name": { "family": "Farley", "given": "K. A." }, "orcid": "0000-0002-7846-7546" }, { "id": "Fassett-C-I", "name": { "family": "Fassett", "given": "C. I." }, "orcid": "0000-0001-9155-3804" }, { "id": "Fischer-W-W", "name": { "family": "Fischer", "given": "W. W." }, "orcid": "0000-0002-8836-3054" }, { "id": "Fraeman-A-A", "name": { "family": "Fraeman", "given": "A. A." }, "orcid": "0000-0003-4017-5158" }, { "id": "Golombek-M-P", "name": { "family": "Golombek", "given": "M. P." }, "orcid": "0000-0002-1928-2293" }, { "id": "Hamilton-V-E", "name": { "family": "Hamilton", "given": "V. E." }, "orcid": "0000-0001-8675-2083" }, { "id": "Hayes-A-G", "name": { "family": "Hayes", "given": "A. G." } }, { "id": "Herd-C-D-K", "name": { "family": "Herd", "given": "C. D. K." } }, { "id": "Horgan-B-H", "name": { "family": "Horgan", "given": "B." } }, { "id": "Hu-R", "name": { "family": "Hu", "given": "R." } }, { "id": "Jakosky-B-M", "name": { "family": "Jakosky", "given": "B. M." } }, { "id": "Johnson-J-R", "name": { "family": "Johnson", "given": "J. R." }, "orcid": "0000-0002-5586-4901" }, { "id": "Kasting-J-F", "name": { "family": "Kasting", "given": "J. F." }, "orcid": "0000-0003-4042-2067" }, { "id": "Kerber-L", "name": { "family": "Kerber", "given": "L." } }, { "id": "Kinch-K-M", "name": { "family": "Kinch", "given": "K. M." }, "orcid": "0000-0002-4629-8880" }, { "id": "Kite-E-S", "name": { "family": "Kite", "given": "E. S." }, "orcid": "0000-0002-1426-1186" }, { "id": "Knutson-H-A", "name": { "family": "Knutson", "given": "H. A." }, "orcid": "0000-0002-5375-4725" }, { "id": "Lunine-J-I", "name": { "family": "Lunine", "given": "J. I." }, "orcid": "0000-0003-2279-4131" }, { "id": "Mahaffy-P-R", "name": { "family": "Mahaffy", "given": "P. R." }, "orcid": "0000-0003-1896-1726" }, { "id": "Mangold-N", "name": { "family": "Mangold", "given": "N." }, "orcid": "0000-0002-0022-0631" }, { "id": "McCubbin-F-M", "name": { "family": "McCubbin", "given": "F. M." } }, { "id": "Mustard-J-F", "name": { "family": "Mustard", "given": "J. F." } }, { "id": "Niles-P-B", "name": { "family": "Niles", "given": "P. B." } }, { "id": "Quantin-Nataf-C", "name": { "family": "Quantin-Nataf", "given": "C." } }, { "id": "Rice-M-S", "name": { "family": "Rice", "given": "M. S." }, "orcid": "0000-0002-8370-4139" }, { "id": "Stack-K-M", "name": { "family": "Stack", "given": "K. M." }, "orcid": "0000-0003-3444-6695" }, { "id": "Stevenson-D-J", "name": { "family": "Stevenson", "given": "D. J." }, "orcid": "0000-0001-9432-7159" }, { "id": "Stewart-S-T", "name": { "family": "Stewart", "given": "S. T." } }, { "id": "Toplis-M-J", "name": { "family": "Toplis", "given": "M. J." } }, { "id": "Usui-T", "name": { "family": "Usui", "given": "T." } }, { "id": "Weiss-B-P", "name": { "family": "Weiss", "given": "B. P." } }, { "id": "Werner-S-C", "name": { "family": "Werner", "given": "S. C." } }, { "id": "Wordsworth-R-D", "name": { "family": "Wordsworth", "given": "R. D." }, "orcid": "0000-0003-1127-8334" }, { "id": "Wray-J-J", "name": { "family": "Wray", "given": "J. J." } }, { "id": "Yingst-R-A", "name": { "family": "Yingst", "given": "R. A." }, "orcid": "0000-0002-0628-4265" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Y. L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Zahnle-K-J", "name": { "family": "Zahnle", "given": "K. J." } } ] }, "title": "The Sustainability of Habitability on Terrestrial Planets: Insights, Questions, and Needed Measurements from Mars for Understanding the Evolution of Earth-like Worlds", "ispublished": "pub", "full_text_status": "public", "keywords": "Mars history; Planetary evolution; Habitability; Sustainability; Terrestrial exoplanets", "note": "\u00a9 2016 American Geophysical Union. This is an open access article under the terms of the Creative Commons Attribution-NonCommercial-NoDerivs License, which permits use and distribution in any medium, provided the original work is properly cited, the use is non-commercial and no modifications or adaptations are made. \n\nAccepted manuscript online: 15 September 2016; Manuscript Accepted: 13 September 2016; Manuscript Revised: 12 September 2016; Manuscript Received: 16 July 2016. \n\nOne of us (Y.L.Y.) thanks Vlada Stamenkovic for illuminating discussions of the Martian atmosphere at the KISS Workshop on Methane on Mars. As per AGU's data availability policy, this paper is a review paper and contains no new data. Thanks to two reviewers and the editor for comments that improved this manuscript.\n\nPublished - Ehlmann_et_al-2016-Journal_of_Geophysical_Research-_Planets.pdf
", "abstract": "What allows a planet to be both within a potentially habitable zone and sustain habitability over long geologic time? With the advent of exoplanetary astronomy and the ongoing discovery of terrestrial-type planets around other stars, our own solar system becomes a key testing ground for ideas about what factors control planetary evolution. Mars provides the solar system's longest record of the interplay of the physical and chemical processes relevant to habitability on an accessible rocky planet with an atmosphere and hydrosphere. Here we review current understanding and update the timeline of key processes in early Mars history. We then draw on knowledge of exoplanets and the other solar system terrestrial planets to identify six broad questions of high importance to the development and sustaining of habitability (unprioritized): (1) Is small planetary size fatal? (2) How do magnetic fields influence atmospheric evolution? (3) To what extent does starting composition dictate subsequent evolution, including redox processes and the availability of water and organics? (4) Does early impact bombardment have a net deleterious or beneficial influence? (5) How do planetary climates respond to stellar evolution, e.g., sustaining early liquid water in spite of a faint young Sun? (6) How important are the timescales of climate forcing and their dynamical drivers? Finally, we suggest crucial types of Mars measurements (unprioritized) to address these questions: (1) in situ petrology at multiple units/sites; (2) continued quantification of volatile reservoirs and new isotopic measurements of H, C, N, O, S, Cl, and noble gases in rocks that sample multiple stratigraphic sections; (3) radiometric age dating of units in stratigraphic sections and from key volcanic and impact units; (4) higher-resolution measurements of heat flux, subsurface structure, and magnetic field anomalies coupled with absolute age dating. Understanding the evolution of early Mars will feed forward to understanding the factors driving the divergent evolutionary paths of the Earth, Venus, and thousands of small rocky extrasolar planets yet to be discovered.", "date": "2016-10", "date_type": "published", "publication": "Journal of Geophysical Research. Planets", "volume": "121", "number": "10", "publisher": "American Geophysical Union", "pagerange": "1927-1961", "id_number": "CaltechAUTHORS:20160916-124841566", "issn": "2169-9097", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160916-124841566", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1002/2016JE005134", "primary_object": { "basename": "Ehlmann_et_al-2016-Journal_of_Geophysical_Research-_Planets.pdf", "url": "https://authors.library.caltech.edu/records/jp6c1-n2g81/files/Ehlmann_et_al-2016-Journal_of_Geophysical_Research-_Planets.pdf" }, "resource_type": "article", "pub_year": "2016", "author_list": "Ehlmann, B. L.; Anderson, F. S.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/phwsb-40t85", "eprint_id": 69057, "eprint_status": "archive", "datestamp": "2023-08-22 18:39:17", "lastmod": "2023-10-20 16:29:07", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Guo-Jianping", "name": { "family": "Guo", "given": "Jianping" }, "orcid": "0000-0001-8530-8976" }, { "id": "Liu-Huan", "name": { "family": "Liu", "given": "Huan" } }, { "id": "Wang-Fu", "name": { "family": "Wang", "given": "Fu" } }, { "id": "Huang-Jingfeng", "name": { "family": "Huang", "given": "Jingfeng" } }, { "id": "Xia-Feng", "name": { "family": "Xia", "given": "Feng" } }, { "id": "Lou-Mengyun", "name": { "family": "Lou", "given": "Mengyun" } }, { "id": "Wu-Yerong", "name": { "family": "Wu", "given": "Yerong" } }, { "id": "Jiang-Jonathan-H", "name": { "family": "Jiang", "given": "Jonathan H." }, "orcid": "0000-0002-5929-8951" }, { "id": "Xie-Tao", "name": { "family": "Xie", "given": "Tao" } }, { "id": "Zhaxi-Yangzong", "name": { "family": "Zhaxi", "given": "Yangzong" } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Three-dimensional structure of aerosol in China: A perspective from multi-satellite observations", "ispublished": "pub", "full_text_status": "public", "keywords": "CALIOP; Dust; Smoke; Frequency of occurrence; China", "note": "\u00a9 2016 Elsevier B.V. \n\nReceived 8 December 2015, Accepted 9 May 2016, Available online 10 May 2016.", "abstract": "Using eight years (2006\u20132014) of passive (MODIS/Aqua and OMI/Aura) and active (CALIOP/CALIPSO) satellite measurements of aerosols, we yield a three-dimensional (3D) distribution of the frequency of occurrence (FoO) of aerosols over China. As an indicator of the vertical heterogeneity of aerosol layers detected by CALIOP, two types of Most Probable Height (MPH), including MPH_FoO and MPH_AOD, are deduced. The FoO of \"Total Aerosol\" reveals significant geographical dependence. Eastern China showed much stronger aerosol FoD than northwestern China. The FoO vertical structures of aerosol layer are strongly dependent on altitudes. Among the eight typical ROIs analyzed, aerosol layers over the Gobi Desert have the largest occurrence probability located at an altitude as high as 2.83 km, as compared to 1.26 km over Beijing\u2013Tianjin\u2013Hebei. The diurnal variation (nighttime\u2013daytime) in MPH_AOD varies from an altitude as low as 0.07 km over the Sichuan basin to 0.27 km over the Gobi Desert, whereas the magnitude of the diurnal variation in terms of MPH_AOD is six times as large as the MPH_FoO, mostly attributable to the day/night lidar SNR difference. Also, the 3D distribution of dust and smoke aerosols was presented. The multi-sensor synergized 3D observations of dust aerosols, frequently observed in the zonal belt of 38\u00b0N\u201345\u00b0N, is markedly different from that of smoke aerosols that are predominantly located in the eastern and southern parts. The 3D FoO distribution of dust indicates a west-to-east passageway of dust originating from the westernmost Taklimakan Desert all the way to North China Plain (NCP). The findings from the multi-sensor synergetic observations greatly improved our understanding on the long-range aerosol dispersion, transport and passageway over China.", "date": "2016-09-01", "date_type": "published", "publication": "Atmospheric Research", "volume": "178-179", "publisher": "Elsevier", "pagerange": "580-589", "id_number": "CaltechAUTHORS:20160715-103942562", "issn": "0169-8095", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160715-103942562", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/j.atmosres.2016.05.010", "resource_type": "article", "pub_year": "2016", "author_list": "Guo, Jianping; Liu, Huan; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/3wtr8-05e66", "eprint_id": 90301, "eprint_status": "archive", "datestamp": "2023-08-22 18:19:57", "lastmod": "2023-10-18 23:21:32", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Feng-Sha", "name": { "family": "Feng", "given": "Sha" }, "orcid": "0000-0002-2376-0868" }, { "id": "Lauvaux-T", "name": { "family": "Lauvaux", "given": "Thomas" } }, { "id": "Newman-S", "name": { "family": "Newman", "given": "Sally" }, "orcid": "0000-0003-0710-995X" }, { "id": "Rao-Preeti", "name": { "family": "Rao", "given": "Preeti" }, "orcid": "0000-0002-5549-0583" }, { "id": "Ahmadov-R", "name": { "family": "Ahmadov", "given": "Ravan" } }, { "id": "Deng-Aijun-J", "name": { "family": "Deng", "given": "Aijun" } }, { "id": "D\u00edaz-Isaac-L-I", "name": { "family": "D\u00edaz-Isaac", "given": "Liza I." } }, { "id": "Duren-R-M", "name": { "family": "Duren", "given": "Riley M." }, "orcid": "0000-0003-4723-5280" }, { "id": "Fischer-M-L", "name": { "family": "Fischer", "given": "Marc L." }, "orcid": "0000-0001-7956-2361" }, { "id": "Gerbig-C", "name": { "family": "Gerbig", "given": "Christoph" }, "orcid": "0000-0002-1112-8603" }, { "id": "Gurney-K-R", "name": { "family": "Gurney", "given": "Kevin R." }, "orcid": "0000-0001-9218-7164" }, { "id": "Huang-Jianhua", "name": { "family": "Huang", "given": "Jianhua" } }, { "id": "Jeong-Seongeun", "name": { "family": "Jeong", "given": "Seongeun" }, "orcid": "0000-0003-2032-0127" }, { "id": "Li-Zhijin", "name": { "family": "Li", "given": "Zhijin" } }, { "id": "Miller-C-E", "name": { "family": "Miller", "given": "Charles E." }, "orcid": "0000-0002-9380-4838" }, { "id": "O'Keeffe-D", "name": { "family": "O'Keeffe", "given": "Darragh" } }, { "id": "Patarasuk-R", "name": { "family": "Patarasuk", "given": "Risa" }, "orcid": "0000-0002-3961-4662" }, { "id": "Sander-S-P", "name": { "family": "Sander", "given": "Stanley P." }, "orcid": "0000-0003-1424-3620" }, { "id": "Song-Yang", "name": { "family": "Song", "given": "Yang" } }, { "id": "Wong-Kam-W", "name": { "family": "Wong", "given": "Kam W." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Los Angeles megacity: a high-resolution land\u2013atmosphere modelling system for urban CO_2 emissions", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 Author(s) 2016. This work is distributed under the Creative Commons Attribution 3.0 License. \n\nReceived: 15 Feb 2016 \u2013 Discussion started: 21 Mar 2016 \u2013 Revised: 22 Jun 2016 \u2013 Accepted: 04 Jul 2016 \u2013 Published: 22 Jul 2016. \n\nA portion of this work was performed at the Jet Propulsion Laboratory, California Institute of Technology, under contract with NASA. The Megacities Carbon Project is sponsored in part by the National Institute of Standards and Technology (NIST). Sally Newman acknowledges funding from the Caltech/JPL President & Director's Research and Development Fund. Kevin R. Gurney thanks NIST grant 70NANB14H321. Ravan Ahmadov was supported by the US Weather Research Program within the NOAA/OAR Office of Weather and Air Quality. Seongeun Jeong and Marc L. Fischer acknowledge the support by the Laboratory Directed Research and Development Program, Office of Science, of the US Department of Energy under contract no. DE-AC02-05CH11231. Thanks to W. Angevine at NOAA for radar wind profiler data, K. Aikin at NOAA for Aircraft WP-3D data, and B. Lefer at University of Houston for ceilometer data. \n\nEdited by: R. Cohen. Reviewed by: I. Super and one anonymous referee. \n\nAuthor contributions. Sha Feng and Thomas Lauvaux designed the model experiments, evaluated the model performance, and developed the assessment of the measuring network; Sally Newman provided the calibrated CO_2 measurements and support for the model evaluations. Preeti Rao, Risa Patarasuk, Darragh O'Keeffe, Jianhua Huang, Yang Song, and Kevin R. Gurney developed and prepared the Vulcan and Hestia emission products; Ravan Ahmadov contributed to the development of the WRF-VPRM model and relevant guidance; Aijun Deng provided quality control for the observations from the National Weather Stations; Liza I. D\u00edaz-Isaac tested PBL algorithms; Seongeun Jeong and Marc L. Fischer provided the background CO_2 concentration for the LA megacity (region); Riley M. Duren, Christoph Gerbig, Zhijin Li, Charles E. Miller, Stanley P. Sander, Kam W. Wong, and Yuk L. Yung provided comments and discussion on the results of the study. \n\nData availability: The model output can be accessed by request (sfeng@psu.edu). Both the Vulcan and Hestia fossil fuel CO_2 emissions data products can be accessed by request (kevin.gurney@asu.edu). Access and information about National Weather Service data can be found at www.weather.gov. Access and information about CalNex data can be found at http://www.esrl.noaa.gov/csd/groups/csd7/measurements/2010calnex/.\n\nPublished - acp-16-9019-2016.pdf
", "abstract": "Megacities are major sources of anthropogenic fossil fuel CO_2 (FFCO_2) emissions. The spatial extents of these large urban systems cover areas of 10000 km^2 or more with complex topography and changing landscapes. We present a high-resolution land\u2013atmosphere modelling system for urban CO_2 emissions over the Los Angeles (LA) megacity area. The Weather Research and Forecasting (WRF)-Chem model was coupled to a very high-resolution FFCO_2 emission product, Hestia-LA, to simulate atmospheric CO_2 concentrations across the LA megacity at spatial resolutions as fine as \u2009\u223c\u20091 km. We evaluated multiple WRF configurations, selecting one that minimized errors in wind speed, wind direction, and boundary layer height as evaluated by its performance against meteorological data collected during the CalNex-LA campaign (May\u2013June 2010). Our results show no significant difference between moderate-resolution (4 km) and high-resolution (1.3 km) simulations when evaluated against surface meteorological data, but the high-resolution configurations better resolved planetary boundary layer heights and vertical gradients in the horizontal mean winds. We coupled our WRF configuration with the Vulcan 2.2 (10 km resolution) and Hestia-LA (1.3 km resolution) fossil fuel CO_2 emission products to evaluate the impact of the spatial resolution of the CO_2 emission products and the meteorological transport model on the representation of spatiotemporal variability in simulated atmospheric CO_2 concentrations. We find that high spatial resolution in the fossil fuel CO_2 emissions is more important than in the atmospheric model to capture CO_2 concentration variability across the LA megacity. Finally, we present a novel approach that employs simultaneous correlations of the simulated atmospheric CO_2 fields to qualitatively evaluate the greenhouse gas measurement network over the LA megacity. Spatial correlations in the atmospheric CO_2 fields reflect the coverage of individual measurement sites when a statistically significant number of sites observe emissions from a specific source or location. We conclude that elevated atmospheric CO_2 concentrations over the LA megacity are composed of multiple fine-scale plumes rather than a single homogenous urban dome. Furthermore, we conclude that FFCO_2 emissions monitoring in the LA megacity requires FFCO_2 emissions modelling with \u2009\u223c\u20091 km resolution because coarser-resolution emissions modelling tends to overestimate the observational constraints on the emissions estimates.", "date": "2016-07-22", "date_type": "published", "publication": "Atmospheric Chemistry and Physics", "volume": "16", "number": "14", "publisher": "European Geosciences Union", "pagerange": "9019-9045", "id_number": "CaltechAUTHORS:20181016-153903710", "issn": "1680-7316", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20181016-153903710", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA/JPL/Caltech" }, { "agency": "National Institute of Standards and Technology (NIST)", "grant_number": "70NANB14H321" }, { "agency": "JPL President and Director's Fund" }, { "agency": "National Oceanic and Atmospheric Administration (NOAA)" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/acp-16-9019-2016", "primary_object": { "basename": "acp-16-9019-2016.pdf", "url": "https://authors.library.caltech.edu/records/3wtr8-05e66/files/acp-16-9019-2016.pdf" }, "resource_type": "article", "pub_year": "2016", "author_list": "Feng, Sha; Lauvaux, Thomas; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/nhhh2-ek158", "eprint_id": 68681, "eprint_status": "archive", "datestamp": "2023-08-22 18:11:52", "lastmod": "2023-10-19 23:11:56", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Hu-Renyu", "name": { "family": "Hu", "given": "Renyu" }, "orcid": "0000-0003-2215-8485" }, { "id": "Bloom-A-A", "name": { "family": "Bloom", "given": "A. Anthony" }, "orcid": "0000-0002-1486-1499" }, { "id": "Gao-Peter", "name": { "family": "Gao", "given": "Peter" }, "orcid": "0000-0002-8518-9601" }, { "id": "Miller-C-E", "name": { "family": "Miller", "given": "Charles E." }, "orcid": "0000-0002-9380-4838" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Hypotheses for Near-Surface Exchange of Methane on Mars", "ispublished": "pub", "full_text_status": "public", "keywords": "Mars; Methane; Astrobiology; Regolith", "note": "\u00a9 2016 Mary Ann Liebert, Inc. publishers. \n\nSubmitted 16 September 2015; Accepted 8 April 2016; Online Ahead of Print: June 17, 2016. \n\nSupport was partially provided by the National Aeronautics and Space Administration (NASA) through Hubble Fellowship grant #51332.01 awarded by the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., for NASA, under contract NAS 5-26555. Y.L.Y. was supported in part by a NAI Virtual Planetary Laboratory grant from the University of Washington to the Jet Propulsion Laboratory (JPL) and California Institute of Technology. The research was carried out at the JPL, California Institute of Technology, under a contract with NASA.\n\nPublished - ast.2015hu,renyu.pdf
Submitted - 1604.08279v1.pdf
", "abstract": "The Curiosity rover recently detected a background of 0.7\u2009ppb and spikes of 7\u2009ppb of methane on Mars. This in situ measurement reorients our understanding of the martian environment and its potential for life, as the current theories do not entail any geological source or sink of methane that varies sub-annually. In particular, the 10-fold elevation during the southern winter indicates episodic sources of methane that are yet to be discovered. Here we suggest a near-surface reservoir could explain this variability. Using the temperature and humidity measurements from the rover, we find that perchlorate salts in the regolith deliquesce to form liquid solutions, and deliquescence progresses to deeper subsurface in the season of the methane spikes. We therefore formulate the following three testable hypotheses. The first scenario is that the regolith in Gale Crater adsorbs methane when dry and releases this methane to the atmosphere upon deliquescence. The adsorption energy needs to be 36\u2009kJ mol^(\u22121) to explain the magnitude of the methane spikes, higher than existing laboratory measurements. The second scenario is that microorganisms convert organic matter in the soil to methane when they are in liquid solutions. This scenario does not require regolith adsorption but entails extant life on Mars. The third scenario is that deep subsurface aquifers produce the bursts of methane. Continued in situ measurements of methane and water, as well as laboratory studies of adsorption and deliquescence, will test these hypotheses and inform the existence of the near-surface reservoir and its exchange with the atmosphere.", "date": "2016-07", "date_type": "published", "publication": "Astrobiology", "volume": "16", "number": "7", "publisher": "Mary Ann Liebert", "pagerange": "539-550", "id_number": "CaltechAUTHORS:20160627-090125055", "issn": "1531-1074", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160627-090125055", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA Hubble Fellowship", "grant_number": "51332.01" }, { "agency": "NASA", "grant_number": "NAS 5-26555" }, { "agency": "University of Washington" }, { "agency": "NASA/JPL/Caltech" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1089/ast.2015.1410", "primary_object": { "basename": "1604.08279v1.pdf", "url": "https://authors.library.caltech.edu/records/nhhh2-ek158/files/1604.08279v1.pdf" }, "related_objects": [ { "basename": "ast.2015hu,renyu.pdf", "url": "https://authors.library.caltech.edu/records/nhhh2-ek158/files/ast.2015hu,renyu.pdf" } ], "resource_type": "article", "pub_year": "2016", "author_list": "Hu, Renyu; Bloom, A. Anthony; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/3k04c-yqd30", "eprint_id": 62251, "eprint_status": "archive", "datestamp": "2023-08-22 17:57:45", "lastmod": "2023-10-25 16:59:57", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Dyudina-U-A", "name": { "family": "Dyudina", "given": "Ulyana" } }, { "id": "Zhang-Xi", "name": { "family": "Zhang", "given": "Xi" } }, { "id": "Li-Liming", "name": { "family": "Li", "given": "Liming" }, "orcid": "0000-0002-5257-9849" }, { "id": "Kopparla-P", "name": { "family": "Kopparla", "given": "Pushkar" }, "orcid": "0000-0002-8951-3907" }, { "id": "Ingersoll-A-P", "name": { "family": "Ingersoll", "given": "Andrew P." }, "orcid": "0000-0002-2035-9198" }, { "id": "Dones-L", "name": { "family": "Dones", "given": "Luke" } }, { "id": "Verbiscer-A-J", "name": { "family": "Verbiscer", "given": "Anne" } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Reflected Light Curves, Spherical and Bond Albedos of Jupiter- and Saturn-like Exoplanets", "ispublished": "pub", "full_text_status": "public", "keywords": "methods: data analysis \u2013 planets and satellites: detection \u2013 planets and satellites: individual (Jupiter, Saturn) \u2013 planets and satellites: surfaces \u2013 scattering", "note": "\u00a9 2016 The American Astronomical Society. \n\nReceived 2015 November 9; accepted 2016 February 25; published 2016 May 10. \n\nThis research was supported by the NASA Cassini Project. We thank R.A. West for his critical comments on the manuscript, references on Jupiter's scattering, and help with image calibration. We thank S.P. Ewald for the comments on the manuscript. We thank the anonymous reviewer for useful suggestions.\n\nPublished - apj_822_2_76.pdf
Submitted - 1511.04415.pdf
", "abstract": "Reflected light curves observed for exoplanets indicate that a few of them host bright clouds. We estimate how the light curve and total stellar heating of a planet depends on forward and backward scattering in the clouds based on Pioneer and Cassini spacecraft images of Jupiter and Saturn. We fit analytical functions to the local reflected brightnesses of Jupiter and Saturn depending on the planet's phase. These observations cover broadbands at 0.59\u20130.72 and 0.39\u20130.5 \u03bcm, and narrowbands at 0.938 (atmospheric window), 0.889 (CH4 absorption band), and 0.24\u20130.28 \u03bcm. We simulate the images of the planets with a ray-tracing model, and disk-integrate them to produce the full-orbit light curves. For Jupiter, we also fit the modeled light curves to the observed full-disk brightness. We derive spherical albedos for Jupiter and Saturn, and for planets with Lambertian and Rayleigh-scattering atmospheres. Jupiter-like atmospheres can produce light curves that are a factor of two fainter at half-phase than the Lambertian planet, given the same geometric albedo at transit. The spherical albedo is typically lower than for a Lambertian planet by up to a factor of ~1.5. The Lambertian assumption will underestimate the absorption of the stellar light and the equilibrium temperature of the planetary atmosphere. We also compare our light curves with the light curves of solid bodies: the moons Enceladus and Callisto. Their strong backscattering peak within a few degrees of opposition (secondary eclipse) can lead to an even stronger underestimate of the stellar heating.", "date": "2016-05-10", "date_type": "published", "publication": "Astrophysical Journal", "volume": "822", "number": "2", "publisher": "American Astronomical Society", "pagerange": "Art. No. 76", "id_number": "CaltechAUTHORS:20151119-135603177", "issn": "0004-637X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20151119-135603177", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.3847/0004-637X/822/2/76", "primary_object": { "basename": "1511.04415.pdf", "url": "https://authors.library.caltech.edu/records/3k04c-yqd30/files/1511.04415.pdf" }, "related_objects": [ { "basename": "apj_822_2_76.pdf", "url": "https://authors.library.caltech.edu/records/3k04c-yqd30/files/apj_822_2_76.pdf" } ], "resource_type": "article", "pub_year": "2016", "author_list": "Dyudina, Ulyana; Zhang, Xi; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/6gq0r-sgr17", "eprint_id": 67580, "eprint_status": "archive", "datestamp": "2023-08-22 17:47:37", "lastmod": "2023-10-18 21:18:18", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Anderson-C-M", "name": { "family": "Anderson", "given": "C. M." } }, { "id": "Samuelson-R-E", "name": { "family": "Samuelson", "given": "R. E." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Y. L." }, "orcid": "0000-0002-4263-2562" }, { "id": "McLain-J-L", "name": { "family": "McLain", "given": "J. L." } } ] }, "title": "Solid-state photochemistry as a formation mechanism for Titan's stratospheric C_4N_2 ice clouds", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2016 American Geophysical Union. \n\nReceived 13 JAN 2016; Accepted 18 MAR 2016; Accepted article online 22 MAR 2016; Published online 14 APR 2016. \n\nThe authors acknowledge funding support from NASA's Cassini Project. C.M.A. and R.E.S. were supported in part by the Cassini Data Analysis and Participating Scientist program. Y.L.Y. was supported in part by the Cassini UVIS program via NASA grant JPL.1459109 to the California Institute of Technology. The CIRS data presented here are archived in the PDS Atmospheres Node at New Mexico State University.\n\nPublished - Anderson_et_al-2016-Geophysical_Research_Letters.pdf
", "abstract": "We propose that C_4N_2 ice clouds observed in Titan's springtime polar stratosphere arise due to solid-state photochemistry occurring within extant ice cloud particles of HCN-HC_3N mixtures. This formation process resembles the halogen-induced ice particle surface chemistry that leads to condensed nitric acid trihydrate (NAT) particles and ozone depletion in Earth's polar stratosphere. As our analysis of the Cassini Composite Infrared Spectrometer 478 cm^(\u22121) ice emission feature demonstrates, this solid-state photochemistry mechanism eliminates the need for the relatively high C_4N_2 saturation vapor pressures required (even though they are not observed) when the ice is produced through the usual procedure of direct condensation from the vapor.", "date": "2016-04-16", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "43", "number": "7", "publisher": "American Geophysical Union", "pagerange": "3088-3094", "id_number": "CaltechAUTHORS:20160602-132342039", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160602-132342039", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "JPL.1459109" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1002/2016GL067795", "primary_object": { "basename": "Anderson_et_al-2016-Geophysical_Research_Letters.pdf", "url": "https://authors.library.caltech.edu/records/6gq0r-sgr17/files/Anderson_et_al-2016-Geophysical_Research_Letters.pdf" }, "resource_type": "article", "pub_year": "2016", "author_list": "Anderson, C. M.; Samuelson, R. E.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/dqbwh-1rc11", "eprint_id": 66451, "eprint_status": "archive", "datestamp": "2023-08-22 17:43:49", "lastmod": "2023-10-18 18:06:12", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Trammell-J-H", "name": { "family": "Trammell", "given": "James H." } }, { "id": "Jiang-Xun", "name": { "family": "Jiang", "given": "Xun" }, "orcid": "0000-0001-8932-3807" }, { "id": "Li-Liming", "name": { "family": "Li", "given": "Liming" }, "orcid": "0000-0002-5257-9849" }, { "id": "Kao-Anglea", "name": { "family": "Kao", "given": "Angela" } }, { "id": "Zhang-Guang-J", "name": { "family": "Zhang", "given": "Guang J." } }, { "id": "Chang-Edmund-K-M", "name": { "family": "Chang", "given": "Edmund K. M." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk" }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Temporal and Spatial Variability of Precipitation from Observations and Models", "ispublished": "pub", "full_text_status": "public", "keywords": "Physical Meteorology and Climatology; Hydrology; Variability; Interannual variability", "note": "\u00a9 2016 American Meteorological Society. \n\nManuscript received 6 May 2015, in final form 23 January 2016. \n\nWe thank two anonymous reviewers and the editor for helpful comments. XJ and YLY are supported by the OCO-2 project, NASA Grant NNX13AK34G NASA, and ROSES-2010 NEWS Grant NNX13AC04G. LL is supported by NASA ROSES Cassini Data Analysis Program.\n\nPublished - jcli-d-15-0325_2E1.pdf
Supplemental Material - 10_2E1175_jcli-d-15-0325_2Es1.doc
", "abstract": "Principal component analysis (PCA) is utilized to explore the temporal and spatial variability of precipitation from GPCP and a CAM5 simulation from 1979 to 2010. In the tropical region, the interannual variability of tropical precipitation is characterized by two dominant modes (El Ni\u00f1o and El Ni\u00f1o Modoki). The first and second modes of tropical GPCP precipitation capture 31.9% and 15.6% of the total variance, respectively. The first mode has positive precipitation anomalies over the western Pacific and negative precipitation anomalies over the central and eastern Pacific. The second mode has positive precipitation anomalies over the central Pacific and negative precipitation anomalies over the western and eastern Pacific. Similar variations are seen in the first two modes of tropical precipitation from a CAM5 simulation, although the magnitudes are slightly weaker than in the observations. Over the Northern Hemisphere (NH) high latitudes, the first mode, capturing 8.3% of the total variance of NH GPCP precipitation, is related to the northern annular mode (NAM). During the positive phase of NAM, there are negative precipitation anomalies over the Arctic and positive precipitation anomalies over the midlatitudes. Over the Southern Hemisphere (SH) high latitudes, the first mode, capturing 13.2% of the total variance of SH GPCP precipitation, is related to the southern annular mode (SAM). During the positive phase of the SAM, there are negative precipitation anomalies over the Antarctic and positive precipitation anomalies over the midlatitudes. The CAM5 precipitation simulation demonstrates similar results to those of the observations. However, they do not capture both the high precipitation anomalies over the northern Pacific Ocean or the position of the positive precipitation anomalies in the SH.", "date": "2016-04-01", "date_type": "published", "publication": "Journal of Climate", "volume": "29", "number": "7", "publisher": "American Meteorological Society", "pagerange": "2543-2555", "id_number": "CaltechAUTHORS:20160425-115702237", "issn": "0894-8755", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160425-115702237", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "OCO-2 Project" }, { "agency": "NASA", "grant_number": "NNX13AK34G" }, { "agency": "NASA", "grant_number": "NNX13AC04G" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1175/JCLI-D-15-0325.1", "primary_object": { "basename": "10_2E1175_jcli-d-15-0325_2Es1.doc", "url": "https://authors.library.caltech.edu/records/dqbwh-1rc11/files/10_2E1175_jcli-d-15-0325_2Es1.doc" }, "related_objects": [ { "basename": "jcli-d-15-0325_2E1.pdf", "url": "https://authors.library.caltech.edu/records/dqbwh-1rc11/files/jcli-d-15-0325_2E1.pdf" } ], "resource_type": "article", "pub_year": "2016", "author_list": "Trammell, James H.; Jiang, Xun; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/s2x4e-yr627", "eprint_id": 63917, "eprint_status": "archive", "datestamp": "2023-08-22 17:39:20", "lastmod": "2023-10-17 18:28:47", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Kopparla-P", "name": { "family": "Kopparla", "given": "Pushkar" }, "orcid": "0000-0002-8951-3907" }, { "id": "Natraj-V", "name": { "family": "Natraj", "given": "Vijay" }, "orcid": "0000-0003-3154-9429" }, { "id": "Spurr-R-J-D", "name": { "family": "Spurr", "given": "Robert" } }, { "id": "Shia-Run-Lie", "name": { "family": "Shia", "given": "Run-Lie" }, "orcid": "0000-0003-1911-3120" }, { "id": "Crisp-D", "name": { "family": "Crisp", "given": "David" }, "orcid": "0000-0002-4573-9998" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "A Fast and Accurate PCA Based Radiative Transfer Model: Extension to the Broadband Shortwave Region", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2016 Elsevier B.V. \n\nReceived 4 August 2015, Revised 4 December 2015, Accepted 10 January 2016, Available online 16 January 2016.", "abstract": "Accurate radiative transfer (RT) calculations are necessary for many earth-atmosphere applications, from remote sensing retrieval to climate modeling. A Principal Component Analysis (PCA)-based spectral binning method has been shown to provide an order of magnitude increase in computational speed while maintaining an overall accuracy of 0.01% (compared to line-by-line calculations) over narrow spectral bands. In this paper, we have extended the PCA method for RT calculations over the entire shortwave region of the spectrum from 0.3 to 3 microns. The region is divided into 33 spectral fields covering all major gas absorption regimes. We find that the RT performance runtimes are shorter by factors between 10-100, while root mean square errors are of order 0.01%.", "date": "2016-04", "date_type": "published", "publication": "Journal of Quantitative Spectroscopy and Radiative Transfer", "volume": "173", "publisher": "Elsevier", "pagerange": "65-71", "id_number": "CaltechAUTHORS:20160125-084322315", "issn": "0022-4073", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160125-084322315", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/j.jqsrt.2016.01.014", "resource_type": "article", "pub_year": "2016", "author_list": "Kopparla, Pushkar; Natraj, Vijay; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/863ad-xpb61", "eprint_id": 67671, "eprint_status": "archive", "datestamp": "2023-08-20 10:58:51", "lastmod": "2023-10-18 21:22:40", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Newman-S", "name": { "family": "Newman", "given": "Sally" }, "orcid": "0000-0003-0710-995X" }, { "id": "Xu-Xiaomei", "name": { "family": "Xu", "given": "Xiaomei" } }, { "id": "Gurney-K-R", "name": { "family": "Gurney", "given": "Kevin R." }, "orcid": "0000-0001-9218-7164" }, { "id": "Hsu-Ying-Kuang", "name": { "family": "Hsu", "given": "Ying Kuang" } }, { "id": "Li-King-Fai", "name": { "family": "Li", "given": "King Fai" }, "orcid": "0000-0003-0150-2910" }, { "id": "Jiang-Xun", "name": { "family": "Jiang", "given": "Xun" }, "orcid": "0000-0001-8932-3807" }, { "id": "Keeling-R", "name": { "family": "Keeling", "given": "Ralph" }, "orcid": "0000-0002-9749-2253" }, { "id": "Feng-Sha", "name": { "family": "Feng", "given": "Sha" }, "orcid": "0000-0002-2376-0868" }, { "id": "O'Keefe-D", "name": { "family": "O'Keefe", "given": "Darragh" } }, { "id": "Patarasuk-R", "name": { "family": "Patarasuk", "given": "Risa" }, "orcid": "0000-0002-3961-4662" }, { "id": "Wong-Kam-Weng", "name": { "family": "Wong", "given": "Kam Weng" } }, { "id": "Rao-Preeti", "name": { "family": "Rao", "given": "Preeti" }, "orcid": "0000-0002-5549-0583" }, { "id": "Fischer-M-L", "name": { "family": "Fischer", "given": "Marc L." }, "orcid": "0000-0001-7956-2361" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Toward consistency between trends in bottom-up CO_2 emissions and top-down atmospheric measurements in the Los Angeles megacity", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 Author(s) 2016. This work is distributed under the Creative Commons Attribution 3.0 License. \n\nReceived: 09 Sep 2015. Published in Atmos. Chem. Phys. Discuss.: 29 Oct 2015. Revised: 05 Mar 2016. Accepted: 07 Mar 2016. Published: 22 Mar 2016. \n\nThis work would not have been possible without support from the W. M. Keck Carbon Cycle Facility at UCI. We specifically thank J. Southon for his help with sample analysis. We acknowledge funding from the Keck Institute for Space Studies, NASA Grant NNX13AC04G, and NASA Grant NNX13AK34G. We also acknowledge funding from the California Air Resources Board Contract #13-329. The statements and conclusions in this report are those of the Contract and not necessarily those of the California Air Resources Board. The mention of commercial products, their source, or their use in connection with materials reported herein is not to be construed as actual or implied endorsement of such products. The authors gratefully acknowledge the NOAA Air Resources Laboratory (ARL) for providing the HYSPLIT transport and dispersion model used in this publication. We thank N. C. Shu for hosting the site on the Palos Verdes peninsula.\n\nPublished - acp-16-3843-2016.pdf
", "abstract": "Large urban emissions of greenhouse gases result in large atmospheric enhancements relative to background that are easily measured. Using CO_2 mole fractions and \u0394^(14)C and \u03b4^(13)C values of CO_2 in the Los Angeles megacity observed in inland Pasadena (2006\u20132013) and coastal Palos Verdes peninsula (autumn 2009\u20132013), we have determined time series for CO_2 contributions from fossil fuel combustion (C_(ff)) for both sites and broken those down into contributions from petroleum and/or gasoline and natural gas burning for Pasadena. We find a 10 % reduction in Pasadena C_(ff) during the Great Recession of 2008\u20132010, which is consistent with the bottom-up inventory determined by the California Air Resources Board. The isotopic variations and total atmospheric CO_2 from our observations are used to infer seasonality of natural gas and petroleum combustion. The trend of CO_2 contributions to the atmosphere from natural gas combustion is out of phase with the seasonal cycle of total natural gas combustion seasonal patterns in bottom-up inventories but is consistent with the seasonality of natural gas usage by the area's electricity generating power plants. For petroleum, the inferred seasonality of CO_2 contributions from burning petroleum is delayed by several months relative to usage indicated by statewide gasoline taxes. Using the high-resolution Hestia-LA data product to compare C_(ff) from parts of the basin sampled by winds at different times of year, we find that variations in observed fossil fuel CO_2 reflect seasonal variations in wind direction. The seasonality of the local CO_2 excess from fossil fuel combustion along the coast, on Palos Verdes peninsula, is higher in autumn and winter than spring and summer, almost completely out of phase with that from Pasadena, also because of the annual variations of winds in the region. Variations in fossil fuel CO_2 signals are consistent with sampling the bottom-up Hestia-LA fossil CO_2 emissions product for sub-city source regions in the LA megacity domain when wind directions are considered.", "date": "2016-03-22", "date_type": "published", "publication": "Atmospheric Chemistry and Physics", "volume": "16", "number": "6", "publisher": "European Geosciences Union", "pagerange": "3843-3863", "id_number": "CaltechAUTHORS:20160606-075449018", "issn": "1680-7324", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160606-075449018", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Keck Institute for Space Studies (KISS)" }, { "agency": "NASA", "grant_number": "NNX13AC04G" }, { "agency": "NASA", "grant_number": "NNX13AK34G" }, { "agency": "California Air Resources Board", "grant_number": "13-329" } ] }, "local_group": { "items": [ { "id": "Keck-Institute-for-Space-Studies" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/acp-16-3843-2016", "primary_object": { "basename": "acp-16-3843-2016.pdf", "url": "https://authors.library.caltech.edu/records/863ad-xpb61/files/acp-16-3843-2016.pdf" }, "resource_type": "article", "pub_year": "2016", "author_list": "Newman, Sally; Xu, Xiaomei; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/rzyab-nqn17", "eprint_id": 65692, "eprint_status": "archive", "datestamp": "2023-08-22 17:36:57", "lastmod": "2023-10-18 16:42:19", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Gladstone-G-R", "name": { "family": "Gladstone", "given": "G. Randall" } }, { "id": "Wong-Michael-L", "name": { "family": "Wong", "given": "Michael L." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "The atmosphere of Pluto as observed by New Horizons", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2016 American Association for the Advancement of Science. \n\nReceived 16 November 2015; accepted 17 February 2016. \n\nWe thank the NASA's New Horizons project for their excellent and long-term support. We thank our colleagues B. B\u00e9zard, J. Erwin, F. Forget, M. Gurwell, S. Gusewich, C. Hansen, A. Heays, K. L. Jessup, V. Krasnopolsky, E. Lellouch, B. Lewis, B. Sicardy, G. Stark, K. Stothoff, A. Toigo, R. Vervack, and R. Yelle for excellent advice, data, and useful comments. We thank the reviewers for their very useful comments. S.A.S. is also affiliated with Florida Space Institute, Uwingu, Golden Spike Co., and World View Enterprises. N.J.C. was a paid consultant to Southwest Research Institute. As contractually agreed to with NASA, fully calibrated New Horizons Pluto system data will be released via the NASA Planetary Data System at https://pds.nasa.gov in a series of stages in 2016 and 2017 owing to the time required to fully downlink and calibrate the data set.\n\nAccepted Version - 1604.05356.pdf
Supplemental Material - Gladstone-SM.pdf
", "abstract": "In July 2015, the New Horizons spacecraft flew through the Pluto system at high speed, humanity's first close look at this enigmatic system on the outskirts of our solar system. In a series of papers, the New Horizons team present their analysis of the encounter data downloaded so far: Moore et al. present the complex surface features and geology of Pluto and its large moon Charon, including evidence of tectonics, glacial flow, and possible cryovolcanoes. Grundy et al. analyzed the colors and chemical compositions of their surfaces, with ices of H_2O, CH_4, CO, N_2, and NH_3 and a reddish material which may be tholins. Gladstone et al. investigated the atmosphere of Pluto, which is colder and more compact than expected and hosts numerous extensive layers of haze. Weaver et al. examined the small moons Styx, Nix, Kerberos, and Hydra, which are irregularly shaped, fast-rotating, and have bright surfaces. Bagenal et al. report how Pluto modifies its space environment, including interactions with the solar wind and a lack of dust in the system. Together, these findings massively increase our understanding of the bodies in the outer solar system. They will underpin the analysis of New Horizons data, which will continue for years to come.", "date": "2016-03-18", "date_type": "published", "publication": "Science", "volume": "351", "number": "6279", "publisher": "American Association for the Advancement of Science", "pagerange": "Art. No. aad8866", "id_number": "CaltechAUTHORS:20160328-082616130", "issn": "0036-8075", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160328-082616130", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1126/science.aad8866", "primary_object": { "basename": "1604.05356.pdf", "url": "https://authors.library.caltech.edu/records/rzyab-nqn17/files/1604.05356.pdf" }, "related_objects": [ { "basename": "Gladstone-SM.pdf", "url": "https://authors.library.caltech.edu/records/rzyab-nqn17/files/Gladstone-SM.pdf" } ], "resource_type": "article", "pub_year": "2016", "author_list": "Gladstone, G. Randall; Wong, Michael L.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/x7se8-2g190", "eprint_id": 50322, "eprint_status": "archive", "datestamp": "2023-08-22 17:17:03", "lastmod": "2023-10-17 22:55:40", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Jiang-Xun", "name": { "family": "Jiang", "given": "Xun" }, "orcid": "0000-0001-8932-3807" }, { "id": "Crisp-D", "name": { "family": "Crisp", "given": "David" }, "orcid": "0000-0002-4573-9998" }, { "id": "Olsen-E-T", "name": { "family": "Olsen", "given": "Edward T." } }, { "id": "Kulawik-S-S", "name": { "family": "Kulawik", "given": "Susan S." } }, { "id": "Miller-C-E", "name": { "family": "Miller", "given": "Charles E." }, "orcid": "0000-0002-9380-4838" }, { "id": "Pagano-T-S", "name": { "family": "Pagano", "given": "Thomas S." } }, { "id": "Liang-Mao-Chang", "name": { "family": "Liang", "given": "MaoChang" }, "orcid": "0000-0002-5294-9344" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "CO_2 Annual and Semiannual Cycles From Multiple Satellite Retrievals and Models", "ispublished": "pub", "full_text_status": "public", "keywords": "Satellite CO_2 Retrievals; Model Simulations; CO_2 Annual and semiannual Cycles", "note": "\u00a9 2016 The Authors.\nThis is an open access article under the\nterms of the Creative Commons\nAttribution-NonCommercial-NoDerivs\nLicense, which permits use and distribution\nin any medium, provided the\noriginal work is properly cited, the use is\nnon-commercial and no modifications\nor adaptations are made.\n\nReceived 18 OCT 2014;\nAccepted 19 JAN 2016;\nAccepted article online 22 JAN 2016;\nPublished online 18 FEB 2016.\n\nWe thank M. Gerstell, anonymous\nreviewers, and the Editor for the helpful\ncomments. CarbonTracker CT 2013\nresults are provided by NOAA ESRL,\nBoulder, Colorado, USA from the website\nat http://carbontracker.noaa.gov/.\nTCCON results are obtained from the\nTCCON data archive, operated by the\nCalifornia Institute of Technology from\nthe website at http://tccon.ipac.caltech.\nedu/. X. Jiang and YLY were supported\nby NASA grant NNX13AK34G to Caltech\nand UH. Part of the research was carried\nout at the Jet Propulsion Laboratory,\nCalifornia Institute of Technology, under\na contract with the National Aeronautics\nand Space Administration.\n\nPublished - Jiang_et_al-2016-Earth_and_Space_Science.pdf
", "abstract": "Satellite CO_2 retrievals from the Greenhouse gases Observing SATellite (GOSAT), Atmospheric Infrared Sounder (AIRS), and Tropospheric Emission Spectrometer (TES) and in situ measurements from the National Oceanic and Atmospheric Administration - Earth System Research Laboratory (NOAA-ESRL) Surface CO_2 and Total Carbon Column Observing Network (TCCON) are utilized to explore the CO_2 variability at different altitudes. A multiple regression method is used to calculate the CO_2 annual cycle and semiannual cycle amplitudes from different data sets. The CO_2 annual cycle and semiannual cycle amplitudes for GOSAT X_(CO2) and TCCON X_(CO2) are consistent but smaller than those seen in the NOAA-ESRL surface data. The CO_2 annual and semiannual cycles are smallest in the AIRS midtropospheric CO_2 compared with other data sets in the Northern Hemisphere. The amplitudes for the CO_2 annual cycle and semiannual cycle from GOSAT, TES, and AIRS CO_2 are small and comparable to each other in the Southern Hemisphere. Similar regression analysis is applied to the Model for OZone And Related chemical Tracers-2 and CarbonTracker model CO_2. The convolved model CO_2 annual cycle and semiannual cycle amplitudes are similar to those from the satellite CO_2 retrievals, although the models tend to underestimate the CO_2 seasonal cycle amplitudes in the Northern Hemisphere midlatitudes and underestimate the CO_2 semiannual cycle amplitudes in the high latitudes. These results can be used to better understand the vertical structures for the CO_2 annual cycle and semiannual cycle and help identify deficiencies in the models, which are very important for the carbon budget study.", "date": "2016-02", "date_type": "published", "publication": "Earth and Space Science", "volume": "3", "number": "2", "publisher": "American Geophysical Union", "pagerange": "78-87", "id_number": "CaltechAUTHORS:20141009-161520265", "issn": "2333-5084", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20141009-161520265", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NNX13AK34G" }, { "agency": "NASA/JPL/Caltech" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1002/2014EA000045", "primary_object": { "basename": "Jiang_et_al-2016-Earth_and_Space_Science.pdf", "url": "https://authors.library.caltech.edu/records/x7se8-2g190/files/Jiang_et_al-2016-Earth_and_Space_Science.pdf" }, "resource_type": "article", "pub_year": "2016", "author_list": "Jiang, Xun; Crisp, David; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/mjnfc-y9r86", "eprint_id": 91290, "eprint_status": "archive", "datestamp": "2023-09-15 06:11:23", "lastmod": "2023-10-23 21:24:04", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Zhang-Qiong", "name": { "family": "Zhang", "given": "Qiong" }, "orcid": "0000-0002-8762-0557" }, { "id": "Shia-Run-Lie", "name": { "family": "Shia", "given": "Run-Lie" }, "orcid": "0000-0003-1911-3120" }, { "id": "Sander-S-P", "name": { "family": "Sander", "given": "Stanley P." }, "orcid": "0000-0003-1424-3620" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "X_(CO2) retrieval error over deserts near critical surface albedo", "ispublished": "pub", "full_text_status": "public", "keywords": "aerosol scattering; critical surface albedo; X_(CO2) retrieval", "note": "\u00a92016. The Authors. This is an open access article under the terms of the Creative Commons Attribution\u2010NonCommercial\u2010NoDerivs License, which permits use and distribution in any medium, provided the original work is properly cited, the use is non\u2010commercial and no modifications or adaptations are made. \n\nReceived 21 OCT 2015. Accepted 28 DEC 2015. Accepted article online 3 JAN 2016. Published online 3 FEB 2016. \n\nWe thank A. Eldering, M. Gunson, V. Natraj, J. Margolis, S. Newman, and K.\u2010F. Li for their helpful comments. We also thank the Editor, F.C. Seidel, and an anonymous reviewer whose comments helped improve the manuscript significantly. This research was supported in part by NASA grant NNX13AK34G to the California Institute of Technology, a grant from the OCO 2 mission at Jet Propulsion Laboratory, and the KISS program at Caltech. The OCO 2 data used in this study can be downloaded from http://oco.jpl.nasa.gov/science/ocodatacenter/.\n\nPublished - Zhang_et_al-2016-Earth_and_Space_Science.pdf
", "abstract": "Large retrieval errors in column\u2010weighted CO_2 mixing ratio (X_(CO2)) over deserts are evident in the Orbiting Carbon Observatory 2 version 7 L2 products. We argue that these errors are caused by the surface albedo being close to a critical surface albedo (\u03b1_c). Over a surface with albedo close to \u03b1_c, increasing the aerosol optical depth (AOD) does not change the continuum radiance. The spectral signature caused by changing the AOD is identical to that caused by changing the absorbing gas column. The degeneracy in the retrievals of AOD and X_(CO2) results in a loss of degrees of freedom and information content. We employ a two\u2010stream\u2010exact single scattering radiative transfer model to study the physical mechanism of X_(CO2) retrieval error over a surface with albedo close to \u03b1_c. Based on retrieval tests over surfaces with different albedos, we conclude that over a surface with albedo close to \u03b1_c, the X_(CO2) retrieval suffers from a significant loss of accuracy. We recommend a bias correction approach that has significantly improved the X_(CO2) retrieval from the California Laboratory for Atmospheric Remote Sensing data in the presence of aerosol loading.", "date": "2016-02", "date_type": "published", "publication": "Earth and Space Science", "volume": "3", "number": "2", "publisher": "American Geophysical Union", "pagerange": "36-45", "id_number": "CaltechAUTHORS:20181128-113131152", "issn": "2333-5084", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20181128-113131152", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NNX13AK34G" }, { "agency": "OCO-2 Project" }, { "agency": "Keck Institute for Space Studies (KISS)" } ] }, "local_group": { "items": [ { "id": "Keck-Institute-for-Space-Studies" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1002/2015ea000143", "primary_object": { "basename": "Zhang_et_al-2016-Earth_and_Space_Science.pdf", "url": "https://authors.library.caltech.edu/records/mjnfc-y9r86/files/Zhang_et_al-2016-Earth_and_Space_Science.pdf" }, "resource_type": "article", "pub_year": "2016", "author_list": "Zhang, Qiong; Shia, Run-Lie; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/xzasr-7gd63", "eprint_id": 105398, "eprint_status": "archive", "datestamp": "2023-08-22 17:15:28", "lastmod": "2023-10-23 20:06:36", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Kopparla-P", "name": { "family": "Kopparla", "given": "Pushkar" }, "orcid": "0000-0002-8951-3907" }, { "id": "Natraj-V", "name": { "family": "Natraj", "given": "Vijay" }, "orcid": "0000-0003-3154-9429" }, { "id": "Zhang-Xi", "name": { "family": "Zhang", "given": "Xi" } }, { "id": "Swain-M-R", "name": { "family": "Swain", "given": "Mark R." }, "orcid": "0000-0002-0919-4468" }, { "id": "Wiktorowicz-S-J", "name": { "family": "Wiktorowicz", "given": "Sloane J." }, "orcid": "0000-0003-4483-5037" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "A Multiple Scattering Polarized Radiative Transfer Model: Application to HD 189733b", "ispublished": "pub", "full_text_status": "public", "keywords": "planets and satellites: atmospheres; planets and satellites: individual (HD 189733b); polarization; radiative transfer", "note": "\u00a9 2016. The American Astronomical Society. \n\nReceived 2015 July 13; accepted 2015 December 1; published 2016 January 20. \n\nWe thank David Crisp and Renyu Hu for several insightful comments. The paper also greatly benefited from the anonymous referee's reviews. This research was supported in part by the Presiden't and Director's Fund at Caltech and by the NAI Virtual Planetary Laboratory grant from the University of Washington to the Jet Propulsion Laboratory and California Institute of Technology. Part of the research described here was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration. X.Z. was supported by the Bisgrove Scholar Program at the University of Arizona.\n\nPushkar Kopparla et al 2018 ApJ 862 176\n\nPublished - Kopparla_2016_ApJ_817_32.pdf
Accepted Version - 1512.02308.pdf
Erratum - pdf
", "abstract": "We present a multiple scattering vector radiative transfer model that produces disk integrated, full phase polarized light curves for reflected light from an exoplanetary atmosphere. We validate our model against results from published analytical and computational models and discuss a small number of cases relevant to the existing and possible near-future observations of the exoplanet HD 189733b. HD 189733b is arguably the most well observed exoplanet to date and the only exoplanet to be observed in polarized light, yet it is debated if the planet's atmosphere is cloudy or clear. We model reflected light from clear atmospheres with Rayleigh scattering, and cloudy or hazy atmospheres with Mie and fractal aggregate particles. We show that clear and cloudy atmospheres have large differences in polarized light as compared to simple flux measurements, though existing observations are insufficient to make this distinction. Futhermore, we show that atmospheres that are spatially inhomogeneous, such as being partially covered by clouds or hazes, exhibit larger contrasts in polarized light when compared to clear atmospheres. This effect can potentially be used to identify patchy clouds in exoplanets. Given a set of full phase polarimetric measurements, this model can constrain the geometric albedo, properties of scattering particles in the atmosphere, and the longitude of the ascending node of the orbit. The model is used to interpret new polarimetric observations of HD 189733b in a companion paper.", "date": "2016-01-20", "date_type": "published", "publication": "Astrophysical Journal", "volume": "817", "number": "1", "publisher": "American Astronomical Society", "pagerange": "Art. No. 32", "id_number": "CaltechAUTHORS:20200916-090615037", "issn": "1538-4357", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200916-090615037", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Caltech President's Fund" }, { "agency": "University of Washington" }, { "agency": "NASA/JPL/Caltech" }, { "agency": "University of Arizona" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.3847/0004-637x/817/1/32", "primary_object": { "basename": "1512.02308.pdf", "url": "https://authors.library.caltech.edu/records/xzasr-7gd63/files/1512.02308.pdf" }, "related_objects": [ { "basename": "Kopparla_2016_ApJ_817_32.pdf", "url": "https://authors.library.caltech.edu/records/xzasr-7gd63/files/Kopparla_2016_ApJ_817_32.pdf" }, { "basename": "pdf", "url": "https://authors.library.caltech.edu/records/xzasr-7gd63/files/pdf" } ], "resource_type": "article", "pub_year": "2016", "author_list": "Kopparla, Pushkar; Natraj, Vijay; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/w7mak-1ex90", "eprint_id": 91503, "eprint_status": "archive", "datestamp": "2023-08-22 17:09:43", "lastmod": "2023-10-19 22:32:41", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Su-Zhan", "name": { "family": "Su", "given": "Zhan" }, "orcid": "0000-0002-2699-431X" }, { "id": "Xi-Xi", "name": { "family": "Xi", "given": "Xi" } }, { "id": "Natraj-V", "name": { "family": "Natraj", "given": "Vijay" }, "orcid": "0000-0003-3154-9429" }, { "id": "Li-King-Fai", "name": { "family": "Li", "given": "King-Fai" }, "orcid": "0000-0003-0150-2910" }, { "id": "Shia-Run-Lie", "name": { "family": "Shia", "given": "Run-Lie" }, "orcid": "0000-0003-1911-3120" }, { "id": "Miller-C-E", "name": { "family": "Miller", "given": "Charles E." }, "orcid": "0000-0002-9380-4838" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Information-rich spectral channels for simulated retrievals of partial column-averaged methane", "ispublished": "pub", "full_text_status": "public", "keywords": "remote sensing; information analysis; channel selection; methane cycle", "note": "\u00a9 2015 The Authors. This is an open access article under the terms of the Creative Commons Attribution\u2010NonCommercial\u2010NoDerivs License, which permits use and distribution in any medium, provided the original work is properly cited, the use is non\u2010commercial and no modifications or adaptations are made. \n\nReceived 15 JUN 2015; Accepted 16 DEC 2015; Accepted article online 18 DEC 2015; Published online 16 JAN 2016. \n\nThe authors would like to thank Jack Margolis, John Worden, and Christian Frankenberg for their valuable comments. The authors also gratefully acknowledge detailed and helpful comments from three anonymous reviewers. This research is supported by the Orbiting Carbon Observatory 2 (OCO\u20102) project, a NASA Earth System Science Pathfinder (ESSP) mission, and Project JPL.1382974 to California Institute of Technology.\n\nPublished - Su_et_al-2016-Earth_and_Space_Science.pdf
", "abstract": "Space\u2010based remote sensing of the column\u2010averaged methane dry air mole fraction (XCH_4) has greatly increased our understanding of the spatiotemporal patterns in the global methane cycle. The potential to retrieve multiple pieces of vertical profile information would further improve the quantification of CH_4 across space\u2010time scales. We conduct information analysis for channel selection and evaluate the prospects of retrieving multiple pieces of information as well as total column CH_4 from both ground\u2010based and space\u2010based near\u2010infrared remote sensing spectra. We analyze the degrees of freedom of signal (DOF) in the CH_4 absorption bands near 2.3 \u03bcm and 1.6 \u03bcm and select \u223c1% of the channels that contain >95% of the information about the CH_4 profile. The DOF is around 4 for fine ground\u2010based spectra (resolution = 0.01 cm^(\u22121)) and 3 for coarse space\u2010based spectra (resolution = 0.20 cm^(\u22121)) based on channel selection and a signal\u2010to\u2010noise ratio (SNR) of 300. The DOF varies from 2.2 to 3.2 when SNR is between 100 and 300, and spectral resolution is 0.20 cm^(\u22121). Simulated retrieval tests in clear\u2010sky conditions using the selected channels reveal that the retrieved partial column\u2010averaged CH_4 values are not sensitive to the a priori profiles and can reflect local enhancements of CH_4 in different partial air columns. Both the total and partial column\u2010averaged retrieval errors in all tests are within 1% of the true state. These simulated tests highlight the possibility to retrieve up to three to four pieces of information about the vertical distribution of CH_4 in reality.", "date": "2016-01", "date_type": "published", "publication": "Earth and Space Science", "volume": "3", "number": "1", "publisher": "American Geophysical Union", "pagerange": "2-14", "id_number": "CaltechAUTHORS:20181205-103012031", "issn": "2333-5084", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20181205-103012031", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Orbiting Carbon Observatory 2 (OCO-2)" }, { "agency": "NASA" }, { "agency": "JPL", "grant_number": "1382974" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1002/2015ea000120", "primary_object": { "basename": "Su_et_al-2016-Earth_and_Space_Science.pdf", "url": "https://authors.library.caltech.edu/records/w7mak-1ex90/files/Su_et_al-2016-Earth_and_Space_Science.pdf" }, "resource_type": "article", "pub_year": "2016", "author_list": "Su, Zhan; Xi, Xi; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/wpevq-2sn98", "eprint_id": 63337, "eprint_status": "archive", "datestamp": "2023-08-22 16:56:15", "lastmod": "2023-10-25 23:44:30", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Zhang-Xi", "name": { "family": "Zhang", "given": "Xi" } }, { "id": "West-Robert-A", "name": { "family": "West", "given": "Robert A." }, "orcid": "0000-0002-4320-2599" }, { "id": "Irwin-Patrick-G-J", "name": { "family": "Irwin", "given": "Patrick G. J." } }, { "id": "Nixon-Conor-A", "name": { "family": "Nixon", "given": "Conor A." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Aerosol influence on energy balance of the middle atmosphere of Jupiter", "ispublished": "pub", "full_text_status": "public", "keywords": "Earth sciences; Atmospheric science; Astronomy; Planetary sciences", "note": "\u00a9 2015 Macmillan Publishers Limited. This work is licensed under a Creative Commons Attribution 4.0 International License. The images or other third party material in this article are included in the article's Creative Commons license, unless indicated otherwise in the credit line; if the material is not included under the Creative Commons license, users will need to obtain permission from the license holder to reproduce the material. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/. \n\nReceived 14 August 2015; Accepted 18 November 2015; Published 22 December 2015. \n\nWe thank E. Karkoschka, L. Brown, G. Orton, J. Bailey, T. Kostiuk, A. Showman and L. Li for useful discussions and comments. Special thanks to M. Gerstell, P. Gao, R. Hu, P. Kopparla, C. Li, M.C. Liang, S. Newman, R.L. Shia, M. Wong, X. Xi and Q. Zhang for proofreading the manuscript. The early phase of this research was supported by the Outer Planets Research program via NASA Grant JPL 1452240 to the California Institute of Technology. R.A.W. and C.A.N. are supported by the NASA Cassini project. P.G.J.I. acknowledges the support of the UK Science and Technology Facilities Council. \n\nAuthor Contributions: X.Z. carried out the radiative modelling and CIRS spectral retrieval; R.A.W. provided the ISS data; C.A.N. provided the CIRS data; R.A.W. and Y.L.Y. helped with radiative modelling; P.G.J.I. and C.A.N. helped with spectral inversion modelling; all authors contributed to the paper writing.\n\nPublished - ncomms10231.pdf
", "abstract": "Aerosols are ubiquitous in planetary atmospheres in the Solar System. However, radiative forcing on Jupiter has traditionally been attributed to solar heating and infrared cooling of gaseous constituents only, while the significance of aerosol radiative effects has been a long-standing controversy. Here we show, based on observations from the NASA spacecraft Voyager and Cassini, that gases alone cannot maintain the global energy balance in the middle atmosphere of Jupiter. Instead, a thick aerosol layer consisting of fluffy, fractal aggregate particles produced by photochemistry and auroral chemistry dominates the stratospheric radiative heating at middle and high latitudes, exceeding the local gas heating rate by a factor of 5\u201310. On a global average, aerosol heating is comparable to the gas contribution and aerosol cooling is more important than previously thought. We argue that fractal aggregate particles may also have a significant role in controlling the atmospheric radiative energy balance on other planets, as on Jupiter.", "date": "2015-12", "date_type": "published", "publication": "Nature Communications", "volume": "6", "number": "12", "publisher": "Nature Publishing Group", "pagerange": "Art. No. 10231", "id_number": "CaltechAUTHORS:20160104-135003424", "issn": "2041-1723", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160104-135003424", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA/JPL", "grant_number": "1452240" }, { "agency": "Science and Technology Facilities Council (STFC)" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1038/ncomms10231", "pmcid": "PMC4703888", "primary_object": { "basename": "ncomms10231.pdf", "url": "https://authors.library.caltech.edu/records/wpevq-2sn98/files/ncomms10231.pdf" }, "resource_type": "article", "pub_year": "2015", "author_list": "Zhang, Xi; West, Robert A.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/39km3-caw17", "eprint_id": 101092, "eprint_status": "archive", "datestamp": "2023-08-22 16:59:13", "lastmod": "2023-10-19 22:25:51", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Tinetti-G", "name": { "family": "Tinetti", "given": "Giovanna" } }, { "id": "Thrastarson-H", "name": { "family": "Thrastarson", "given": "H." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Y." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "The EChO science case", "ispublished": "pub", "full_text_status": "public", "keywords": "Exoplanets; Spectroscopy; Atmospheric science; IR astronomy; Space missions", "note": "\u00a9 2015 The Author(s). This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. \n\nReceived 10 December 2014; Accepted 26 October 2015; First Online 29 November 2015. \n\nWe would like to thank all the National Space Agencies who supported the EChO phase-A study. We also thank Nick Cowan for useful comments.\n\nPublished - Tinetti2015_Article_TheEChOScienceCase.pdf
", "abstract": "The discovery of almost two thousand exoplanets has revealed an unexpectedly diverse planet population. We see gas giants in few-day orbits, whole multi-planet systems within the orbit of Mercury, and new populations of planets with masses between that of the Earth and Neptune\u2014all unknown in the Solar System. Observations to date have shown that our Solar System is certainly not representative of the general population of planets in our Milky Way. The key science questions that urgently need addressing are therefore: What are exoplanets made of? Why are planets as they are? How do planetary systems work and what causes the exceptional diversity observed as compared to the Solar System? The EChO (Exoplanet Characterisation Observatory) space mission was conceived to take up the challenge to explain this diversity in terms of formation, evolution, internal structure and planet and atmospheric composition. This requires in-depth spectroscopic knowledge of the atmospheres of a large and well-defined planet sample for which precise physical, chemical and dynamical information can be obtained. In order to fulfil this ambitious scientific program, EChO was designed as a dedicated survey mission for transit and eclipse spectroscopy capable of observing a large, diverse and well-defined planet sample within its 4-year mission lifetime. The transit and eclipse spectroscopy method, whereby the signal from the star and planet are differentiated using knowledge of the planetary ephemerides, allows us to measure atmospheric signals from the planet at levels of at least 10\u207b\u2074 relative to the star. This can only be achieved in conjunction with a carefully designed stable payload and satellite platform. It is also necessary to provide broad instantaneous wavelength coverage to detect as many molecular species as possible, to probe the thermal structure of the planetary atmospheres and to correct for the contaminating effects of the stellar photosphere. This requires wavelength coverage of at least 0.55 to 11 \u03bcm with a goal of covering from 0.4 to 16 \u03bcm. Only modest spectral resolving power is needed, with R\u2009~\u2009300 for wavelengths less than 5 \u03bcm and R\u2009~\u200930 for wavelengths greater than this. The transit spectroscopy technique means that no spatial resolution is required. A telescope collecting area of about 1 m\u00b2 is sufficiently large to achieve the necessary spectro-photometric precision: for the Phase A study a 1.13 m\u00b2 telescope, diffraction limited at 3 \u03bcm has been adopted. Placing the satellite at L2 provides a cold and stable thermal environment as well as a large field of regard to allow efficient time-critical observation of targets randomly distributed over the sky. EChO has been conceived to achieve a single goal: exoplanet spectroscopy. The spectral coverage and signal-to-noise to be achieved by EChO, thanks to its high stability and dedicated design, would be a game changer by allowing atmospheric composition to be measured with unparalleled exactness: at least a factor 10 more precise and a factor 10 to 1000 more accurate than current observations. This would enable the detection of molecular abundances three orders of magnitude lower than currently possible and a fourfold increase from the handful of molecules detected to date. Combining these data with estimates of planetary bulk compositions from accurate measurements of their radii and masses would allow degeneracies associated with planetary interior modelling to be broken, giving unique insight into the interior structure and elemental abundances of these alien worlds. EChO would allow scientists to study exoplanets both as a population and as individuals. The mission can target super-Earths, Neptune-like, and Jupiter-like planets, in the very hot to temperate zones (planet temperatures of 300\u20133000 K) of F to M-type host stars. The EChO core science would be delivered by a three-tier survey. The EChO Chemical Census: This is a broad survey of a few-hundred exoplanets, which allows us to explore the spectroscopic and chemical diversity of the exoplanet population as a whole. The EChO Origin: This is a deep survey of a subsample of tens of exoplanets for which significantly higher signal to noise and spectral resolution spectra can be obtained to explain the origin of the exoplanet diversity (such as formation mechanisms, chemical processes, atmospheric escape). The EChO Rosetta Stones: This is an ultra-high accuracy survey targeting a subsample of select exoplanets. These will be the bright \"benchmark\" cases for which a large number of measurements would be taken to explore temporal variations, and to obtain two and three dimensional spatial information on the atmospheric conditions through eclipse-mapping techniques. If EChO were launched today, the exoplanets currently observed are sufficient to provide a large and diverse sample. The Chemical Census survey would consist of\u2009>\u2009160 exoplanets with a range of planetary sizes, temperatures, orbital parameters and stellar host properties. Additionally, over the next 10 years, several new ground- and space-based transit photometric surveys and missions will come on-line (e.g. NGTS, CHEOPS, TESS, PLATO), which will specifically focus on finding bright, nearby systems. The current rapid rate of discovery would allow the target list to be further optimised in the years prior to EChO's launch and enable the atmospheric characterisation of hundreds of planets.", "date": "2015-12", "date_type": "published", "publication": "Experimental Astronomy", "volume": "40", "number": "2-3", "publisher": "Springer", "pagerange": "329-391", "id_number": "CaltechAUTHORS:20200203-153746857", "issn": "0922-6435", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200203-153746857", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1007/s10686-015-9484-8", "primary_object": { "basename": "Tinetti2015_Article_TheEChOScienceCase.pdf", "url": "https://authors.library.caltech.edu/records/39km3-caw17/files/Tinetti2015_Article_TheEChOScienceCase.pdf" }, "resource_type": "article", "pub_year": "2015", "author_list": "Tinetti, Giovanna; Thrastarson, H.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/c7srf-vza30", "eprint_id": 63339, "eprint_status": "archive", "datestamp": "2023-08-22 16:54:16", "lastmod": "2023-10-25 23:44:35", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Wang-Shuhui", "name": { "family": "Wang", "given": "Shuhui" } }, { "id": "Zhang-Qiong", "name": { "family": "Zhang", "given": "Qiong" }, "orcid": "0000-0002-8762-0557" }, { "id": "Mill\u00e1n-L", "name": { "family": "Mill\u00e1n", "given": "Luis" } }, { "id": "Li-King-Fai", "name": { "family": "Li", "given": "King-Fai" }, "orcid": "0000-0003-0150-2910" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Sander-S-P", "name": { "family": "Sander", "given": "Stanley P." }, "orcid": "0000-0003-1424-3620" }, { "id": "Livesey-N-J", "name": { "family": "Livesey", "given": "Nathaniel J." } }, { "id": "Santee-M-L", "name": { "family": "Santee", "given": "Michelle L." } } ] }, "title": "First evidence of middle atmospheric HO_2 response to 27 day solar cycles from satellite observations", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2015 American Geophysical Union. \n\nReceived 6 JUL 2015; Accepted 12 OCT 2015; Accepted article online 14 OCT 2015; Published online 16 NOV 2015. \n\nWe acknowledge the support of the\nNASA Aura Science Team, Upper\nAtmosphere Research, and\nTropospheric Chemistry programs.\nWork at the Jet Propulsion Laboratory,\nCalifornia Institute of Technology, was\ndone under contract to the National\nAeronautics and Space Administration.\nWe acknowledge the LASP Interactive\nSolar Irradiance Datacenter (LISIRD) for\nLyman \u03b1 record (http://lasp.colorado.\nedu/lisird/).\n\nPublished - Wang_et_al-2015-Geophysical_Research_Letters.pdf
Supplemental Material - grl53616-sup-0001-s04.pdf
Supplemental Material - grl53616-sup-0002-s05.txt
", "abstract": "HO_2 and OH, also known as HO_x, play an important role in controlling middle atmospheric O_3. Due to their photochemical production and short chemical lifetimes, HO_x are expected to respond rapidly to solar irradiance changes, resulting in O_3 variability. While OH solar cycle signals have been investigated, HO_2 studies have been limited by the lack of reliable observations. Here we present the first evidence of HO_2 variability during solar 27\u2009day cycles by investigating the recently developed HO_2 data from the Aura Microwave Limb Sounder (MLS). We focus on 2012\u20132015, when solar variability is strong near the peak of Solar Cycle 24. The features of HO_2 variability, with the strongest signals at 0.01\u20130.068\u2009hPa, correlate well with those of solar Lyman \u03b1. When continuous MLS OH observations are not available, the new HO_2 data could be a promising alternative for investigating HO_x variability and the corresponding impacts on O_3 and the climate.", "date": "2015-11-28", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "42", "number": "22", "publisher": "American Geophysical Union", "pagerange": "10004-10009", "id_number": "CaltechAUTHORS:20160104-135519357", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160104-135519357", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA/JPL/Caltech" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1002/2015GL065237", "primary_object": { "basename": "Wang_et_al-2015-Geophysical_Research_Letters.pdf", "url": "https://authors.library.caltech.edu/records/c7srf-vza30/files/Wang_et_al-2015-Geophysical_Research_Letters.pdf" }, "related_objects": [ { "basename": "grl53616-sup-0001-s04.pdf", "url": "https://authors.library.caltech.edu/records/c7srf-vza30/files/grl53616-sup-0001-s04.pdf" }, { "basename": "grl53616-sup-0002-s05.txt", "url": "https://authors.library.caltech.edu/records/c7srf-vza30/files/grl53616-sup-0002-s05.txt" } ], "resource_type": "article", "pub_year": "2015", "author_list": "Wang, Shuhui; Zhang, Qiong; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/tyrtr-zn941", "eprint_id": 63123, "eprint_status": "archive", "datestamp": "2023-08-20 09:07:18", "lastmod": "2023-10-25 23:33:35", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Xi-Xi", "name": { "family": "Xi", "given": "X." } }, { "id": "Natraj-V", "name": { "family": "Natraj", "given": "V." }, "orcid": "0000-0003-3154-9429" }, { "id": "Shia-Run-Lie", "name": { "family": "Shia", "given": "R. L." }, "orcid": "0000-0003-1911-3120" }, { "id": "Luo-M", "name": { "family": "Luo", "given": "M." } }, { "id": "Zhang-Q", "name": { "family": "Zhang", "given": "Q." } }, { "id": "Newman-S", "name": { "family": "Newman", "given": "S." }, "orcid": "0000-0003-0710-995X" }, { "id": "Sander-S-P", "name": { "family": "Sander", "given": "S. P." }, "orcid": "0000-0003-1424-3620" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Y. L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Simulated retrievals for the remote sensing of CO_2, CH_4, CO, and H_2O from geostationary orbit", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2015 Author(s). This work is distributed under the Creative Commons Attribution 3.0 License. Published by Copernicus Publications on behalf of the European Geosciences Union. \n\nReceived: 21 April 2015 \u2013 Published in Atmos. Meas. Tech. Discuss.: 12 June 2015; Revised: 3 September 2015 \u2013 Accepted: 5 October 2015 \u2013 Published: 18 November 2015. \n\nThe authors would like to thank Renyu Hu, Pushkar Kopparla, Michael Wong, Le Kuai, Clare (Kam Weng) Wong, and Dejian Fu for helpful discussions. The authors also appreciate technical support from Michael Black and administrative support from Margaret Carlos and Irma Black. Valuable comments and suggestions from two reviewers are greatly appreciated. This research was supported in part by NASA grant NNX13AK34G to the California Institute of Technology, grant P1367828 from the Jet Propulsion Laboratory, and the KISS program at California Institute of Technology.\n\nPublished - amt-8-4817-2015.pdf
", "abstract": "The Geostationary Fourier Transform Spectrometer (GeoFTS) is designed to measure high-resolution spectra of reflected sunlight in three near-infrared bands centered around 0.76, 1.6, and 2.3 \u03bcm and to deliver simultaneous retrievals of column-averaged dry air mole fractions of CO_2, CH_4, CO, and H_2O (denoted XCO_2, XCH_4, XCO, and XH_2O, respectively) at different times of day over North America. In this study, we perform radiative transfer simulations over both clear-sky and all-sky scenes expected to be observed by GeoFTS and estimate the prospective performance of retrievals based on results from Bayesian error analysis and characterization. \n\nWe find that, for simulated clear-sky retrievals, the average retrieval biases and single-measurement precisions are < 0.2 % for XCO_2, XCH_4, and XH_2O, and < 2 % for XCO, when the a priori values have a bias of 3 % and an uncertainty of 3 %. In addition, an increase in the amount of aerosols and ice clouds leads to a notable increase in the retrieval biases and slight worsening of the retrieval precisions. Furthermore, retrieval precision is a strong function of signal-to-noise ratio and spectral resolution. This simulation study can help guide decisions on the design of the GeoFTS observing system, which can result in cost-effective measurement strategies while achieving satisfactory levels of retrieval precisions and biases. The simultaneous retrievals at different times of day will be important for more accurate estimation of carbon sources and sinks on fine spatiotemporal scales and for studies related to the atmospheric component of the water cycle.", "date": "2015-11-18", "date_type": "published", "publication": "Atmospheric Measurement Techniques", "volume": "8", "number": "11", "publisher": "European Geosciences Union", "pagerange": "4817-4830", "id_number": "CaltechAUTHORS:20151222-083951345", "issn": "1867-8548", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20151222-083951345", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NNX13AK34G" }, { "agency": "JPL", "grant_number": "P1367828" }, { "agency": "Keck Institute for Space Studies (KISS)" } ] }, "local_group": { "items": [ { "id": "Keck-Institute-for-Space-Studies" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/amt-8-4817-2015", "primary_object": { "basename": "amt-8-4817-2015.pdf", "url": "https://authors.library.caltech.edu/records/tyrtr-zn941/files/amt-8-4817-2015.pdf" }, "resource_type": "article", "pub_year": "2015", "author_list": "Xi, X.; Natraj, V.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/dwck5-chq27", "eprint_id": 63075, "eprint_status": "archive", "datestamp": "2023-08-22 16:48:48", "lastmod": "2023-10-25 23:29:54", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Wiktorowicz-S-J", "name": { "family": "Wiktorowicz", "given": "Sloane J." }, "orcid": "0000-0003-4483-5037" }, { "id": "Nofi-L-A", "name": { "family": "Nofi", "given": "Larissa A." } }, { "id": "Jontof-Hutter-D", "name": { "family": "Jontof-Hutter", "given": "Daniel" }, "orcid": "0000-0002-6227-7510" }, { "id": "Kopparla-P", "name": { "family": "Kopparla", "given": "Pushkar" }, "orcid": "0000-0002-8951-3907" }, { "id": "Laughlin-G-P", "name": { "family": "Laughlin", "given": "Gregory P." }, "orcid": "0000-0002-3253-2621" }, { "id": "Hermis-N", "name": { "family": "Hermis", "given": "Ninos" } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Swain-M-R", "name": { "family": "Swain", "given": "Mark R." }, "orcid": "0000-0002-0919-4468" } ] }, "title": "A Ground-based Albedo Upper Limit for HD 189733b from Polarimetry", "ispublished": "pub", "full_text_status": "public", "keywords": "dust, extinction; planetary systems; planets and satellites: atmospheres; planets and satellites: individual (HD 189733b); polarization; techniques: polarimetric", "note": "\u00a9 2015. The American Astronomical Society. \n\nReceived 2015 July 13; accepted 2015 September 29; published 2015 October 27. \n\nWe would like to acknowledge the tireless efforts of the Lick Observatory staff. This work was performed (in part) under contract with the California Institute of Technology (Caltech) funded by NASA through the Sagan Fellowship Program executed by the NASA Exoplanet Science Institute. S.J.W. and L.A.N. acknowledge support from the NASA Origins of Solar Systems program through grant NNX13AF63G. P.K. and Y.L.Y. acknowledge support from an NAI Virtual Planetary Laboratory grant from the University of Washington to the Jet Propulsion Laboratory and California Institute of Technology. Research at Lick Observatory is partially supported by a generous gift from Google. \n\nFacility:\u2009Shane (POLISH2) - .\n\nPublished - Wiktorowicz_2015.pdf
Accepted Version - 1507.03588.pdf
", "abstract": "We present 50 nights of polarimetric observations of HD 189733 in the B band using the POLISH2 aperture-integrated polarimeter at the Lick Observatory Shane 3-m telescope. This instrument, commissioned in 2011, is designed to search for Rayleigh scattering from short-period exoplanets due to the polarized nature of scattered light. Since these planets are spatially unresolvable from their host stars, the relative contribution of the planet-to-total system polarization is expected to vary with an amplitude of the order of 10 parts per million (ppm) over the course of the orbit. Non-zero and also variable at the 10 ppm level, the inherent polarization of the Lick 3-m telescope limits the accuracy of our measurements and currently inhibits conclusive detection of scattered light from this exoplanet. However, the amplitude of observed variability conservatively sets a 99.7% confidence upper limit to the planet-induced polarization of the system of 60 ppm in the B band, which is consistent with a previous upper limit from the POLISH instrument at the Palomar Observatory 5-m telescope. A physically motivated Rayleigh scattering model, which includes the depolarizing effects of multiple scattering, is used to conservatively set a 99.7% confidence upper limit to the geometric albedo of HD 189733b of A_g < 0.40. This value is consistent with the value A_g = 0.226 \u00b10.091 derived from occultation observations with Hubble Space Telescope STIS, but it is inconsistent with the large A_g = 0.61 \u00b1 .012 albedo reported by Berdyugina et al.", "date": "2015-11-01", "date_type": "published", "publication": "Astrophysical Journal", "volume": "813", "number": "1", "publisher": "American Astronomical Society", "pagerange": "Art. No. 48", "id_number": "CaltechAUTHORS:20151218-114523995", "issn": "0004-637X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20151218-114523995", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA/Caltech" }, { "agency": "NASA Sagan Fellowship" }, { "agency": "NASA", "grant_number": "NNX13AF63G" }, { "agency": "NAI Virtual Planetary Laboratory" }, { "agency": "Google" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1088/0004-637X/813/1/48", "primary_object": { "basename": "1507.03588.pdf", "url": "https://authors.library.caltech.edu/records/dwck5-chq27/files/1507.03588.pdf" }, "related_objects": [ { "basename": "Wiktorowicz_2015.pdf", "url": "https://authors.library.caltech.edu/records/dwck5-chq27/files/Wiktorowicz_2015.pdf" } ], "resource_type": "article", "pub_year": "2015", "author_list": "Wiktorowicz, Sloane J.; Nofi, Larissa A.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/4zgs1-q5p58", "eprint_id": 62359, "eprint_status": "archive", "datestamp": "2023-08-22 16:45:42", "lastmod": "2023-10-25 17:05:19", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Hu-Renyu", "name": { "family": "Hu", "given": "Renyu" }, "orcid": "0000-0003-2215-8485" }, { "id": "Kass-David-M", "name": { "family": "Kass", "given": "David M." }, "orcid": "0000-0002-7154-2566" }, { "id": "Ehlmann-B-L", "name": { "family": "Ehlmann", "given": "Bethany L." }, "orcid": "0000-0002-2745-3240" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Tracing the fate of carbon and the atmospheric evolution of Mars", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2015 Macmillan Publishers Limited. This work is licensed under a Creative Commons Attribution 4.0 International License. The images or other third party material in this article are included in the article's Creative Commons license, unless indicated otherwise in the credit line; if the material is not included under the Creative Commons license, users will need to obtain permission from the license holder to reproduce the material. \n\nReceived 17 Jul 2015 | Accepted 26 Oct 2015 | Published 24 Nov 2015 \n\nSupport for this work was provided by NASA through Hubble Fellowship grant #51332 awarded by the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., for NASA, under contract NAS 5-26555. The research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration. \n\nContributions: R.H. modelled the fractionation factor of photochemical escape, developed the million-model approach, simulated the evolution scenarios and wrote the manuscript; D.M.K. provided the framework of the evolution model and modelled the fractionation factor of sputtering; B.L.E. assembled the measurements of carbonate content in rock and soil, and provided geological constraints on scenarios; Y.L.Y. provided the insight into the evolution of stellar radiation and escape rates; all authors interpreted the results and commented on the manuscript. \n\nThe authors declare no competing financial interests.\n\nPublished - ncomms10003.pdf
", "abstract": "The climate of Mars likely evolved from a warmer, wetter early state to the cold, arid current state. However, no solutions for this evolution have previously been found to satisfy the observed geological features and isotopic measurements of the atmosphere. Here we show that a family of solutions exist, invoking no missing reservoirs or loss processes. Escape of carbon via CO photodissociation and sputtering enriches heavy carbon (^(13)C) in the Martian atmosphere, partially compensated by moderate carbonate precipitation. The current atmospheric ^(13)C/^(12)C and rock and soil carbonate measurements indicate an early atmosphere with a surface pressure <1\u2009bar. Only scenarios with large amounts of carbonate formation in open lakes permit higher values up to 1.8\u2009bar. The evolutionary scenarios are fully testable with data from the MAVEN mission and further studies of the isotopic composition of carbonate in the Martian rock record through time.", "date": "2015-11", "date_type": "published", "publication": "Nature Communications", "volume": "6", "number": "11", "publisher": "Nature Publishing Group", "pagerange": "Art. No. 10003", "id_number": "CaltechAUTHORS:20151124-094136642", "issn": "2041-1723", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20151124-094136642", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA Hubble Fellowship", "grant_number": "51332" }, { "agency": "NASA", "grant_number": "NAS 5-26555" }, { "agency": "NASA/JPL/Caltech" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1038/ncomms10003", "pmcid": "PMC4673500", "primary_object": { "basename": "ncomms10003.pdf", "url": "https://authors.library.caltech.edu/records/4zgs1-q5p58/files/ncomms10003.pdf" }, "resource_type": "article", "pub_year": "2015", "author_list": "Hu, Renyu; Kass, David M.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/1r4dd-cv404", "eprint_id": 91255, "eprint_status": "archive", "datestamp": "2023-08-22 16:43:00", "lastmod": "2023-10-19 22:20:41", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Kuai-Le", "name": { "family": "Kuai", "given": "Le" }, "orcid": "0000-0001-6406-1150" }, { "id": "Worden-J-R", "name": { "family": "Worden", "given": "John R." }, "orcid": "0000-0003-0257-9549" }, { "id": "Campbell-J-E", "name": { "family": "Campbell", "given": "J. Elliott" } }, { "id": "Kulawik-S-S", "name": { "family": "Kulawik", "given": "Susan S." } }, { "id": "Li-King-Fai", "name": { "family": "Li", "given": "King-Fai" }, "orcid": "0000-0003-0150-2910" }, { "id": "Lee-Meemong", "name": { "family": "Lee", "given": "Meemong" }, "orcid": "0000-0002-8797-8209" }, { "id": "Weidner-R-J", "name": { "family": "Weidner", "given": "Richard J." } }, { "id": "Montzka-S-A", "name": { "family": "Montzka", "given": "Stephen A." } }, { "id": "Moore-F-L", "name": { "family": "Moore", "given": "Fred L." } }, { "id": "Berry-J-A", "name": { "family": "Berry", "given": "Joe A." } }, { "id": "Baker-I-T", "name": { "family": "Baker", "given": "Ian" } }, { "id": "Denning-A-S", "name": { "family": "Denning", "given": "A. Scott" } }, { "id": "Bian-Huisheng", "name": { "family": "Bian", "given": "Huisheng" } }, { "id": "Bowman-K-W", "name": { "family": "Bowman", "given": "Kevin W." }, "orcid": "0000-0002-8659-1117" }, { "id": "Liu-Junjie", "name": { "family": "Liu", "given": "Junjie" }, "orcid": "0000-0002-7184-6594" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Estimate of carbonyl sulfide tropical oceanic surface fluxes using Aura Tropospheric Emission Spectrometer observations", "ispublished": "pub", "full_text_status": "public", "keywords": "carbonyl sulfide; tropical ocean flux; Tropospheric Emissions Spectrometer (TES); HIAPER Pole\u2010to\u2010Pole Observations (HIPPO)", "note": "\u00a9 2015. American Geophysical Union. \n\nReceived 8 APR 2015. Accepted 28 AUG 2015. Accepted article online 4 SEP 2015. Published online 23 OCT 2015. \n\nThis work was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration. King\u2010Fai Li was supported in part by the UCAR Jack Eddy Fellowship and by the NASA grant (NNX14AR40G) to the University of Washington. Yuk L. Yung acknowledged support by NASA grant (NNX13AK34G) to Caltech. The authors would like to acknowledge Randy Kawa for the help with the OH flux data and also thank Steve Wofsy, Elliot Atlas, Benjamin R. Miller, Fred Moore, James Elkins, and all other HIPPO, NOAA team members (the pilots, mechanics, technicians, and scientific crew) for making the HIPPO and NOAA data available. HIPPO was supported by NSF grants ATM\u20100628575, ATM\u20100628519, and ATM\u20100628388 and by the National Center for Atmospheric Research (NCAR). NCAR is supported by the NSF. The data used in this paper are archived at Jet Propulsion Laboratory and are available from the authors upon request (kl@gps.caltech.edu).\n\nPublished - Kuai_et_al-2015-Journal_of_Geophysical_Research_3A_Atmospheres.pdf
", "abstract": "Quantifying the carbonyl sulfide (OCS) land/ocean fluxes contributes to the understanding of both the sulfur and carbon cycles. The primary sources and sinks of OCS are very likely in a steady state because there is no significant observed trend or interannual variability in atmospheric OCS measurements. However, the magnitude and spatial distribution of the dominant ocean source are highly uncertain due to the lack of observations. In particular, estimates of the oceanic fluxes range from approximately 280\u2009Gg\u2009S\u2009yr^(\u22121) to greater than 800\u2009Gg\u2009S\u2009yr^(\u22121), with the larger flux needed to balance a similarly sized terrestrial sink that is inferred from NOAA continental sites. Here we estimate summer tropical oceanic fluxes of OCS in 2006 using a linear flux inversion algorithm and new OCS data acquired by the Aura Tropospheric Emissions Spectrometer (TES). Modeled OCS concentrations based on these updated fluxes are consistent with HIAPER Pole\u2010to\u2010Pole Observations during 4th airborne campaign and improve significantly over the a priori model concentrations. The TES tropical ocean estimate of 70\u2009\u00b1\u200916\u2009Gg\u2009S in June, when extrapolated over the whole year (about 840\u2009\u00b1\u2009192\u2009Gg\u2009S\u2009yr^(\u22121), supports the hypothesis proposed by Berry et al. (2013) that the ocean flux is in the higher range of approximately 800\u2009Gg\u2009S\u2009yr^(\u22121).", "date": "2015-10-27", "date_type": "published", "publication": "Journal of Geophysical Research. Atmospheres", "volume": "120", "number": "20", "publisher": "American Geophysical Union", "pagerange": "11012-11023", "id_number": "CaltechAUTHORS:20181127-160003070", "issn": "2169-897X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20181127-160003070", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA/JPL/Caltech" }, { "agency": "University Corporation for Atmospheric Research" }, { "agency": "NASA", "grant_number": "NNX14AR40G" }, { "agency": "NASA", "grant_number": "NNX13AK34G" }, { "agency": "NSF", "grant_number": "ATM\u20100628575" }, { "agency": "NSF", "grant_number": "ATM\u20100628519" }, { "agency": "NSF", "grant_number": "ATM-0628388" }, { "agency": "National Center for Atmospheric Research (NCAR)" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1002/2015jd023493", "primary_object": { "basename": "Kuai_et_al-2015-Journal_of_Geophysical_Research_3A_Atmospheres.pdf", "url": "https://authors.library.caltech.edu/records/1r4dd-cv404/files/Kuai_et_al-2015-Journal_of_Geophysical_Research_3A_Atmospheres.pdf" }, "resource_type": "article", "pub_year": "2015", "author_list": "Kuai, Le; Worden, John R.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/k10t7-yq064", "eprint_id": 59980, "eprint_status": "archive", "datestamp": "2023-08-22 16:21:33", "lastmod": "2023-10-24 14:47:30", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Jessup-K-L", "name": { "family": "Jessup", "given": "Kandis Lea" } }, { "id": "Marcq-E", "name": { "family": "Marcq", "given": "Emmanuel" } }, { "id": "Mills-F-P", "name": { "family": "Mills", "given": "Franklin" } }, { "id": "Mahieux-A", "name": { "family": "Mahieux", "given": "Arnaud" } }, { "id": "Limaye-S-S", "name": { "family": "Limaye", "given": "Sanjay" } }, { "id": "Wilson-C-F", "name": { "family": "Wilson", "given": "Colin" } }, { "id": "Allen-M-A", "name": { "family": "Allen", "given": "Mark" } }, { "id": "Bertaux-J-L", "name": { "family": "Bertaux", "given": "Jean-Loup" } }, { "id": "Markiewicz-W", "name": { "family": "Markiewicz", "given": "Wojciech" } }, { "id": "Roman-T", "name": { "family": "Roman", "given": "Tony" } }, { "id": "Vandaele-A-C", "name": { "family": "Vandaele", "given": "Ann-Carine" } }, { "id": "Wilquet-V", "name": { "family": "Wilquet", "given": "Val\u00e9rie" } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk" }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Coordinated Hubble Space Telescope and Venus Express Observations of Venus' upper cloud deck", "ispublished": "pub", "full_text_status": "restricted", "keywords": "Venus; Venus, atmosphere; Atmospheres, composition; Atmospheres, chemistry", "note": "\u00a9 2015 Elsevier Inc.\n\nReceived 23 December 2014;\nRevised 21 May 2015;\nAccepted 27 May 2015;\nAvailable online 16 June 2015.\n\nThe authors are grateful to the editor and two anonymous\nreviewers for providing thoughtful and constructive critique of\nthe original manuscript. The authors are also grateful to Marty\nSnow of the Laboratory for Atmospheric and Space Physics at\nUniversity of Colorado, Boulder for providing SOLSTICE data at high\nspectral (0.33 \u00c5) sampling. The authors are grateful to Brad Sandor\nfor coordinating and acquiring the JCMT data, and hours of useful\nconversation and discourse. Investigator Sandor was supported\nby the U.S. National Science Foundation under Grant no.\nAST-1312985, and by NASA under Grant nos. NNX10AB33G,\nNNX12AI32G, and NNX14AK05G toward completion of this\nresearch.\nThe authors also acknowledge the James Clerk Maxwell\nTelescope which has historically been operated by the Joint\nAstronomy Centre on behalf of the Science and Technology\nFacilities Council of the United Kingdom, the National Research\nCouncil of Canada and the Netherlands Organization for Scientific\nResearch.\nThe authors also thank the International Space Science Institute\n(ISSI) for their fruitful support of the documentation of these\nobservations. Most of the authors of this manuscript were members\nof the ISSI International Team ''Sulfur Dioxide variability in the Venus atmosphere'' who met during the years 2013\u20132015 in\nthe facilities of ISSI in Bern, Switzerland.\nFinally the authors are most grateful to Adriana Ocampo, NASA\nHeadquarters, John Grunsfield, NASA Headquarters, Alan Stern,\nSwRI, Claus Leither, Space Telescope Science Institute, Hvakam\nSvedhem, Venus Express Project Scientist, and the VEx Science\nWorking Team, for their support in the acquisition and analysis\nof the HST observations obtained through NASA/HST program\n12433. This research was funded through the NASA Early Careers\nProgram, NASA Grant NNX11AN81G; the NASA Planetary\nAtmospheres Program, Grant NNX12AG55G and through a grant\nfrom Space Science Telescope Institute, which is operated by the\nAssociation of Universities for Research in Astronomy, Inc., under\nNAS5-26555.", "date": "2015-09-15", "date_type": "published", "publication": "Icarus", "volume": "258", "publisher": "Elsevier", "pagerange": "309-336", "id_number": "CaltechAUTHORS:20150831-090349390", "issn": "0019-1035", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150831-090349390", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "AST-1312985" }, { "agency": "NASA", "grant_number": "NNX10AB33G" }, { "agency": "NASA", "grant_number": "NNX12AI32G" }, { "agency": "NASA", "grant_number": "NNX14AK05G" }, { "agency": "NASA Early Careers Program" }, { "agency": "NASA", "grant_number": "NNX11AN81G" }, { "agency": "NASA", "grant_number": "NNX12AG55G" }, { "agency": "NASA", "grant_number": "NAS5-26555" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/j.icarus.2015.05.027", "resource_type": "article", "pub_year": "2015", "author_list": "Jessup, Kandis Lea; Marcq, Emmanuel; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/cxm07-db488", "eprint_id": 59495, "eprint_status": "archive", "datestamp": "2023-08-22 16:18:02", "lastmod": "2023-10-23 20:39:39", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Kim-Sang-Joon", "name": { "family": "Kim", "given": "Sang Joon" } }, { "id": "Sim-Chae-Kyung", "name": { "family": "Sim", "given": "Chae Kyung" } }, { "id": "Ho-Jin", "name": { "family": "Ho", "given": "Jin" } }, { "id": "Geballe-T-R", "name": { "family": "Geballe", "given": "Thomas R." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Miller-S", "name": { "family": "Miller", "given": "Steve" } }, { "id": "Kim-Yong-Ha", "name": { "family": "Kim", "given": "Yong Ha" } } ] }, "title": "Hot CH_4 in the polar regions of Jupiter", "ispublished": "pub", "full_text_status": "restricted", "keywords": "Jupiter; Spectroscopy; Aurorae; Infrared observations; Atmospheres, composition", "note": "\u00a9 2015 Elsevier. \n\nReceived 19 January 2015; Revised 27 March 2015; Accepted 7 May 2015; Available online 15 May 2015. \n\nThis paper is based on observations obtained at the Gemini Observatory, which is operated by the Association of Universities for Research in Astronomy, Inc., under a cooperative agreement with the NSF on behalf of the Gemini partnership: the National Science Foundation (United States), the National Research Council (Canada), CONICYT (Chile), the Australian Research Council (Australia), Minist\u00e9rio da Ci\u00eancia, Tecnologia e Inova\u00e7\u00e3o (Brazil) and Ministerio de Ciencia, Tecnolog\u00eda e Innovaci\u00f3n Productiva (Argentina). SJK acknowledges support from the Brain Korea 21 Plus (BK21+) program through the National Research Foundation of Korea funded by the Ministry of Education, Science and Technology, and from the Korean Astronomy & Space Science Institute under the R&D program supervised by the Ministry of Science, ICT and Future Planning.", "abstract": "We have obtained 3.3\u20133.4-\u03bcm spectro-images of Jupiter including CH_4 and H_3^+ emission lines from both polar regions at the Gemini North telescope. We find that the peak of the 3-\u03bcm CH_4 northern bright spot is located at \u223c200\u00b0 (SysIII) longitude, \u223c20\u00b0 west of the center of the 8-\u03bcm north-polar bright spot, and does not coincide with the 3-\u03bcm H_3^+ bright spot. We derive high temperatures (500\u2013850 K) from CH_4 rotational lines on the bright spots of both polar regions, above the 1-\u03bcbar pressure level, while we find cooler temperatures (<350 K) over the 8-\u03bcm spot. The intensity ratios of the various 3-\u03bcm vibrational bands of CH4 are roughly constant, indicating that the upper states of these bands are mostly populated by non-thermal excitation mechanisms, such as auroral particle precipitation and/or Joule heating, in contrast with the 8-\u03bcm thermal emission.", "date": "2015-09-01", "date_type": "published", "publication": "Icarus", "volume": "257", "publisher": "Elsevier", "pagerange": "217-220", "id_number": "CaltechAUTHORS:20150813-122731563", "issn": "0019-1035", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150813-122731563", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "National Research Foundation of Korea" }, { "agency": "Korean Astronomy & Space Science Institute" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/j.icarus.2015.05.008", "resource_type": "article", "pub_year": "2015", "author_list": "Kim, Sang Joon; Sim, Chae Kyung; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/zqarz-qnj73", "eprint_id": 59327, "eprint_status": "archive", "datestamp": "2023-08-22 16:05:38", "lastmod": "2023-10-23 20:27:10", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Parkinson-C-D", "name": { "family": "Parkinson", "given": "Christopher D." }, "orcid": "0000-0002-5722-2224" }, { "id": "Gao-Peter", "name": { "family": "Gao", "given": "Peter" }, "orcid": "0000-0002-8518-9601" }, { "id": "Schulte-R", "name": { "family": "Schulte", "given": "Rick" } }, { "id": "Bougher-S-W", "name": { "family": "Bougher", "given": "Stephen W." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Bardeen-C-G", "name": { "family": "Bardeen", "given": "Charles G." } }, { "id": "Wilquet-V", "name": { "family": "Wilquet", "given": "Val\u00e9rie" } }, { "id": "Vandaele-A-C", "name": { "family": "Vandaele", "given": "Ann Carine" } }, { "id": "Mahieux-A", "name": { "family": "Mahieux", "given": "Arnaud" } }, { "id": "Tellmann-S", "name": { "family": "Tellmann", "given": "Silvia" } }, { "id": "P\u00e4tzold-M", "name": { "family": "P\u00e4tzold", "given": "Martin" } } ] }, "title": "Distribution of sulphuric acid aerosols in the clouds and upper haze of Venus using Venus Express VAST and VeRa temperature profiles", "ispublished": "pub", "full_text_status": "restricted", "keywords": "Atmospheres composition; Atmospheres structure; Atmospheres dynamics; Venus; Venus atmosphere", "note": "\u00a9 2015 Elsevier Ltd.\n\nReceived 15 March 2014; Received in revised form 8 November 2014; Accepted 27 January 2015; Available online 20 March 2015. \n\nVenus Express is a planetary mission from the European Space Agency (ESA). We wish to thank all ESA members who participated in the mission, in particular, H. Svedhem and D. Titov.\n\nWe thank our collaborators at IASB-BIRA (Belgium), Latmos (France), and IKI (Russia). We thank CNES, CNRS, Roskosmos, and the Russian Academy of Science. The research program was supported by the Belgian Federal Science Policy Office and the European Space Agency (ESA, PRODEX program, contracts C 90268, 90113, and 17645). We acknowledge the support of the \"Interuniversity Attraction Poles\" programme financed by the Belgian government (Planet TOPERS). The research leading to these results has received funding from the European Union Seventh Framework Program (FP7/2007-2013) under grant agreement no. 606798. A. Mahieux thanks the FNRS for the position of \"charg\u00e9 de recherche\".\n\nVeRa is partially funded by the Deutsches Zentrum f\u00fcr Luft- und Raumfahrt (DLR) unter Contract 50 QM 1004.\n\nThe contribution of Bougher was funded in part by subcontract no. B99073JD to Southwest Research Institute.", "abstract": "Observations from Pioneer Venus and from SPICAV/SOIR aboard Venus Express (VEx) have shown the upper haze (UH) of Venus to be highly spatially and temporally variable, and populated by multiple particle size modes. Previous models of this system (e.g., Gao et al., 2014. Icarus 231, 83\u201398), using a typical temperature profile representative of the atmosphere (viz., equatorial VIRA profile), did not investigate the effect of temperature on the UH particle distributions. We show that the inclusion of latitude-dependent temperature profiles for both the morning and evening terminators of Venus helps to explain how the atmospheric aerosol distributions vary spatially. In this work we use temperature profiles obtained by two instruments onboard VEx, VeRa and SPICAV/SOIR, to represent the latitudinal temperature dependence. We find that there are no significant differences between results for the morning and evening terminators at any latitude and that the cloud base moves downwards as the latitude increases due to decreasing temperatures. The UH is not affected much by varying the temperature profiles; however, the haze does show some periodic differences, and is slightly thicker at the poles than at the equator. We also find that the sulphuric acid \"rain\" seen in previous models may be restricted to the equatorial regions of Venus, such that the particle size distribution is relatively stable at higher latitudes and at the poles.", "date": "2015-08", "date_type": "published", "publication": "Planetary and Space Science", "volume": "113-114", "publisher": "Elsevier", "pagerange": "205-218", "id_number": "CaltechAUTHORS:20150810-080319170", "issn": "0032-0633", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150810-080319170", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Belgian Federal Science Policy Office" }, { "agency": "European Space Agency (ESA)", "grant_number": "C 90268" }, { "agency": "European Space Agency (ESA)", "grant_number": "90113" }, { "agency": "European Space Agency (ESA)", "grant_number": "17645" }, { "agency": "Belgian government" }, { "agency": "European Union Seventh Framework Program (FP7/2007-2013)", "grant_number": "606798" }, { "agency": "Deutsches Zentrum f\u00fcr Luft- und Raumfahrt (DLR)", "grant_number": "50 QM 1004" }, { "agency": "Southwest Research Institute", "grant_number": "B99073JD" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/j.pss.2015.01.023", "resource_type": "article", "pub_year": "2015", "author_list": "Parkinson, Christopher D.; Gao, Peter; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/d31pj-fv931", "eprint_id": 59264, "eprint_status": "archive", "datestamp": "2023-08-22 16:05:23", "lastmod": "2023-10-23 20:15:38", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Parkinson-C-D", "name": { "family": "Parkinson", "given": "Christopher D." }, "orcid": "0000-0002-5722-2224" }, { "id": "Gao-Peter", "name": { "family": "Gao", "given": "Peter" }, "orcid": "0000-0002-8518-9601" }, { "id": "Esposito-L-W", "name": { "family": "Esposito", "given": "Larry" } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk" }, "orcid": "0000-0002-4263-2562" }, { "id": "Bougher-S", "name": { "family": "Bougher", "given": "Stephen" } }, { "id": "Hirtzig-M", "name": { "family": "Hirtzig", "given": "Mathieu" } } ] }, "title": "Photochemical control of the distribution of Venusian water", "ispublished": "pub", "full_text_status": "restricted", "keywords": "Venus; Atmosphere; Venus Express", "note": "\u00a9 2015 Elsevier Ltd.\n\nReceived in revised form 2 December 2014; Accepted 2 February 2015; Available online 10 April 2015. \n\nC.D. Parkinson would like to thank X. Zhang for helpful discussions and providing the production and loss figure in this work from his 2012 paper. C.D. Parkinson also acknowledges support with funding in part by NASA Grant #NNX11AD81G to the University of Michigan. C.D. Parkinson also wishes to thank the International Space Science Institute (ISSI) for their fruitful support for Venus team research over 2013\u20132015.\n\nThe contribution of S.W. Bougher was funded in part by subcontract #B99073JD to Southwest Research Institute.\n\nP. Gao and Y. L. Yung were supported in part by the Venus Express program via NASA NNX10AP80G grant to the California Institute of Technology, and in part by an NAI Virtual Planetary Laboratory grant from the University of Washington to the Jet Propulsion Laboratory and California Institute of Technology.", "abstract": "We use the JPL/Caltech 1-D photochemical model to solve continuity diffusion equation for atmospheric constituent abundances and total number density as a function of radial distance from the planet Venus. Photochemistry of the Venus atmosphere from 58 to 112 km is modeled using an updated and expanded chemical scheme (Zhang et al., 2010 and Zhang et al., 2012), guided by the results of recent observations and we mainly follow these references in our choice of boundary conditions for 40 species. We model water between 10 and 35 ppm at our 58 km lower boundary using an SO_2 mixing ratio of 25 ppm as our nominal reference value. We then vary the SO_2 mixing ratio at the lower boundary between 5 and 75 ppm holding water mixing ratio of 18 ppm at the lower boundary and finding that it can control the water distribution at higher altitudes. SO_2 and H_2O can regulate each other via formation of H_2SO_4. In regions of high mixing ratios of SO_2 there exists a \"runaway effect\" such that SO_2 gets oxidized to SO_3, which quickly soaks up H_2O causing a major depletion of water between 70 and 100 km. Eddy diffusion sensitivity studies performed characterizing variability due to mixing that show less of an effect than varying the lower boundary mixing ratio value. However, calculations using our nominal eddy diffusion profile multiplied and divided by a factor of four can give an order of magnitude maximum difference in the SO_2 mixing ratio and a factor of a few difference in the H_2O mixing ratio when compared with the respective nominal mixing ratio for these two species. In addition to explaining some of the observed variability in SO_2 and H_2O on Venus, our work also sheds light on the observations of dark and bright contrasts at the Venus cloud tops observed in an ultraviolet spectrum. Our calculations produce results in agreement with the SOIR Venus Express results of 1 ppm at 70\u201390 km (Bertaux et al., 2007) by using an SO_2 mixing ratio of 25 ppm SO_2 and 18 ppm water as our nominal reference values. Timescales for a chemical bifurcation causing a collapse of water concentrations above the cloud tops (>64 km) are relatively short and on the order of a less than a few months, decreasing with altitude to less than a few days.", "date": "2015-08", "date_type": "published", "publication": "Planetary and Space Science", "volume": "113-114", "publisher": "Elsevier", "pagerange": "226-236", "id_number": "CaltechAUTHORS:20150806-111232910", "issn": "0032-0633", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150806-111232910", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NNX11AD81G" }, { "agency": "Southwest Research Institute", "grant_number": "B99073JD" }, { "agency": "NASA", "grant_number": "NNX10AP80G" }, { "agency": "University of Washington" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/j.pss.2015.02.015", "resource_type": "article", "pub_year": "2015", "author_list": "Parkinson, Christopher D.; Gao, Peter; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/pvf63-mbp44", "eprint_id": 48801, "eprint_status": "archive", "datestamp": "2023-08-22 16:01:52", "lastmod": "2023-10-17 20:26:35", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Zhang-Qiong", "name": { "family": "Zhang", "given": "Qiong" }, "orcid": "0000-0002-8762-0557" }, { "id": "Natraj-V", "name": { "family": "Natraj", "given": "Vijay" }, "orcid": "0000-0003-3154-9429" }, { "id": "Li-King-Fai", "name": { "family": "Li", "given": "King-Fai" }, "orcid": "0000-0003-0150-2910" }, { "id": "Shia-Run-Lie", "name": { "family": "Shia", "given": "Run-Lie" }, "orcid": "0000-0003-1911-3120" }, { "id": "Fu-Dejian", "name": { "family": "Fu", "given": "Dejian" } }, { "id": "Pongetti-T-J", "name": { "family": "Pongetti", "given": "Thomas J." }, "orcid": "0000-0001-9465-0853" }, { "id": "Sander-S-P", "name": { "family": "Sander", "given": "Stanley P." }, "orcid": "0000-0003-1424-3620" }, { "id": "Roehl-C-M", "name": { "family": "Roehl", "given": "Coleen M." }, "orcid": "0000-0001-5383-8462" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Accounting for aerosol scattering in the CLARS retrieval of column averaged CO_2 mixing ratios", "ispublished": "pub", "full_text_status": "public", "keywords": "aerosol; scattering; X_(CO2)", "note": "\u00a9 2015 American Geophysical Union. \n\nReceived 13 APR 2015; Accepted 2 JUL 2015; Accepted article online 3 JUL 2015; Published online 29 JUL 2015. \n\nWe thank Paul Wennberg, C. Wong, J. Margolis, S. Newman, C. Miller, D. Crisp, M. Gerstell, X. Xi, P. Kopparla, P. Gao, R. Hu, and L. Kuai for their helpful comments. We thank Jochen Stutz and his staff for establishing and maintaining the AERONET Caltech site used in this investigation. We also thank the anonymous reviewers whose comments helped improve the manuscript significantly. This research was supported in part by NASA grant NNX13AK34G to the California Institute of Technology, grant P1367828 from the Jet Propulsion Laboratory, and the KISS program at Caltech. Support for CLARS from the California Air Resources Board, NOAA Climate Program, NIST GHG and Climate Science Program, NASA Carbon Cycle Science Program, and JPL Earth Science and Technology Directorate is gratefully acknowledged. TCCON data were obtained from the TCCON Data Archive, hosted by the Carbon Dioxide Information Analysis Center\u2014tccon.onrl.gov. AERONET data for this paper can be downloaded online. CLARS\u2010FTS data are available from the authors upon request.\n\nPublished - Zhang_et_al-2015-Journal_of_Geophysical_Research_3A_Atmospheres.pdf
Submitted - zhang_q_2014_draft_2_11_submitted_copy.pdf
", "abstract": "The California Laboratory for Atmospheric Remote Sensing Fourier transform spectrometer (CLARS\u2010FTS) deployed at Mount Wilson, California, has been measuring column abundances of greenhouse gases in the Los Angeles (LA) basin in the near\u2010infrared spectral region since August 2011. CLARS\u2010FTS measures reflected sunlight and has high sensitivity to absorption and scattering in the boundary layer. In this study, we estimate the retrieval biases caused by aerosol scattering and present a fast and accurate approach to correct for the bias in the CLARS column averaged CO2 mixing ratio product, X_(CO2). The high spectral resolution of 0.06\u2009cm^(\u22121) is exploited to reveal the physical mechanism for the bias. We employ a numerical radiative transfer model to simulate the impact of neglecting aerosol scattering on the CO_2 and O_2 slant column densities operationally retrieved from CLARS\u2010FTS measurements. These simulations show that the CLARS\u2010FTS operational retrieval algorithm likely underestimates CO_2 and O_2 abundances over the LA basin in scenes with moderate aerosol loading. The bias in the CO_2 and O_2 abundances due to neglecting aerosol scattering cannot be canceled by ratioing each other in the derivation of the operational product of X_(CO2). We propose a new method for approximately correcting the aerosol\u2010induced bias. Results for CLARS X_(CO2) are compared to direct\u2010Sun X_(CO2) retrievals from a nearby Total Carbon Column Observing Network (TCCON) station. The bias\u2010correction approach significantly improves the correlation between the X_(CO2) retrieved from CLARS and TCCON, demonstrating that this approach can increase the yield of useful data from CLARS\u2010FTS in the presence of moderate aerosol loading.", "date": "2015-07-27", "date_type": "published", "publication": "Journal of Geophysical Research. Atmospheres", "volume": "120", "number": "14", "publisher": "American Geophysical Union", "pagerange": "7205-7218", "id_number": "CaltechAUTHORS:20140822-092514611", "issn": "2169-897X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140822-092514611", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NNX13AK34G" }, { "agency": "JPL", "grant_number": "P1367828" }, { "agency": "Keck Institute for Space Studies (KISS)" } ] }, "local_group": { "items": [ { "id": "Keck-Institute-for-Space-Studies" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1002/2015JD023499", "primary_object": { "basename": "Zhang_et_al-2015-Journal_of_Geophysical_Research_3A_Atmospheres.pdf", "url": "https://authors.library.caltech.edu/records/pvf63-mbp44/files/Zhang_et_al-2015-Journal_of_Geophysical_Research_3A_Atmospheres.pdf" }, "related_objects": [ { "basename": "zhang_q_2014_draft_2_11_submitted_copy.pdf", "url": "https://authors.library.caltech.edu/records/pvf63-mbp44/files/zhang_q_2014_draft_2_11_submitted_copy.pdf" } ], "resource_type": "article", "pub_year": "2015", "author_list": "Zhang, Qiong; Natraj, Vijay; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/q8jsa-fwz96", "eprint_id": 59872, "eprint_status": "archive", "datestamp": "2023-08-22 15:54:40", "lastmod": "2023-10-23 22:47:37", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Hu-Renyu", "name": { "family": "Hu", "given": "Renyu" }, "orcid": "0000-0003-2215-8485" }, { "id": "Seager-S", "name": { "family": "Seager", "given": "Sara" }, "orcid": "0000-0002-6892-6948" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Helium Atmospheres on Warm Neptune- and Sub-Neptune-sized Exoplanets and Applications to GJ 436b", "ispublished": "pub", "full_text_status": "public", "keywords": "atmospheric effects; planetary systems; planets and satellites: individual (GJ 436b); radiative transfer; techniques: spectroscopic", "note": "\u00a9 2015 The American Astronomical Society.\n\nReceived 19 February 2015; accepted for publication 5 May 2015; published 24 June 2015.\n\nWe appreciate comments on the manuscript made by members of the Yuk Yung research group at the California Institute of Technology. R.H. thanks Robert Johnson, Jeffrey Linsky, and Edwin Kite for helpful discussion. This work has utilized the MUSCLES M dwarf UV radiation database. Support for this work was provided by NASA through Hubble Fellowship grant #51332 awarded by the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., for NASA, under contract NAS 5\u201326555. Y.L.Y. and R.H. (in the later phase of this work) were supported in part by an NAI Virtual Planetary Laboratory grant NASA grant NNX09AB72G to the California Institute of Technology. Part of the research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration.\n\nPublished - 0004-637X_807_1_8.pdf
Submitted - 1505.02221v1.pdf
", "abstract": "Warm Neptune- and sub-Neptune-sized exoplanets in orbits smaller than Mercury's are thought to have experienced extensive atmospheric evolution. Here we propose that a potential outcome of this atmospheric evolution is the formation of helium-dominated atmospheres. The hydrodynamic escape rates of Neptune- and sub-Neptune-sized exoplanets are comparable to the diffusion-limited escape rate of hydrogen, and therefore the escape is heavily affected by diffusive separation between hydrogen and helium. A helium atmosphere can thus be formed\u2014from a primordial hydrogen\u2013helium atmosphere\u2014via atmospheric hydrodynamic escape from the planet. The helium atmosphere has very different abundances of major carbon and oxygen species from those of a hydrogen atmosphere, leading to distinctive transmission and thermal emission spectral features. In particular, the hypothesis of a helium-dominated atmosphere can explain the thermal emission spectrum of GJ 436b, a warm Neptune-sized exoplanet, while also being consistent with the transmission spectrum. This model atmosphere contains trace amounts of hydrogen, carbon, and oxygen, with the predominance of CO over CH4 as the main form of carbon. With our atmospheric evolution model, we find that if the mass of the initial atmosphere envelope is 10^\u22123 planetary mass, hydrodynamic escape can reduce the hydrogen abundance in the atmosphere by several orders of magnitude in ~10 billion years. Observations of exoplanet transits may thus detect signatures of helium atmospheres and probe the evolutionary history of small exoplanets.", "date": "2015-07-01", "date_type": "published", "publication": "Astrophysical Journal", "volume": "807", "number": "1", "publisher": "American Astronomical Society", "pagerange": "Art. No. 8", "id_number": "CaltechAUTHORS:20150825-081127411", "issn": "0004-637X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150825-081127411", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA Hubble Fellowship", "grant_number": "51332" }, { "agency": "NASA", "grant_number": "NAS 5\u201326555" }, { "agency": "NASA", "grant_number": "NNX09AB72G" }, { "agency": "NASA/JPL/Caltech" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1088/0004-637X/807/1/8", "primary_object": { "basename": "0004-637X_807_1_8.pdf", "url": "https://authors.library.caltech.edu/records/q8jsa-fwz96/files/0004-637X_807_1_8.pdf" }, "related_objects": [ { "basename": "1505.02221v1.pdf", "url": "https://authors.library.caltech.edu/records/q8jsa-fwz96/files/1505.02221v1.pdf" } ], "resource_type": "article", "pub_year": "2015", "author_list": "Hu, Renyu; Seager, Sara; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/c805t-23f68", "eprint_id": 59198, "eprint_status": "archive", "datestamp": "2023-08-22 15:45:02", "lastmod": "2023-10-23 20:10:37", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Gao-Peter", "name": { "family": "Gao", "given": "Peter" }, "orcid": "0000-0002-8518-9601" }, { "id": "Hu-Renyu", "name": { "family": "Hu", "given": "Renyu" }, "orcid": "0000-0003-2215-8485" }, { "id": "Robinson-T-D", "name": { "family": "Robinson", "given": "Tyler D." } }, { "id": "Li-Cheng", "name": { "family": "Li", "given": "Cheng" }, "orcid": "0000-0002-8280-3119" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Stability of CO_2 Atmospheres on Desiccated M Dwarf Exoplanets", "ispublished": "pub", "full_text_status": "public", "keywords": "planets and satellites: atmospheres; planets and satellites: physical evolution; planets and satellites: terrestrial planets", "note": "\u00a9 2015 American Astronomical Society. Received 2015 January 29; accepted 2015 May 20; published 2015 June 22.\n\nWe thank K. Willacy, M. Allen, and R. L. Shia for assistance with the setting up and running of the KinetgenX code. We thank V. Meadows and R. Barnes for their valuable inputs. This research was supported in part by the Venus Express program via NASA NNX10AP80G grant to the California Institute of Technology, and was performed as part of the NASA Astrobiology Institute's Virtual Planetary Laboratory Lead Team, supported by NASA through the NASA Astrobiology Institute under solicitation NNH12ZDA002C and Cooperative Agreement Number NNA13AA93A. Support for R.H.\u02bcs work was provided in part by NASA through Hubble Fellowship grant #51332 awarded by the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., for NASA, under contract NAS 5-26555. Part of the research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration.\n\nPublished - 0004-637X_806_2_249.pdf
Submitted - 1501.06876.pdf
", "abstract": "We investigate the chemical stability of CO_2-dominated atmospheres of desiccated M dwarf terrestrial exoplanets using a one-dimensional photochemical model. Around Sun-like stars, CO_2 photolysis by Far-UV (FUV) radiation is balanced by recombination reactions that depend on water abundance. Planets orbiting M dwarf stars experience more FUV radiation, and could be depleted in water due to M dwarfs' prolonged, high-luminosity pre-main sequences. We show that, for water-depleted M dwarf terrestrial planets, a catalytic cycle relying on H_2O_2 photolysis can maintain a CO_2 atmosphere. However, this cycle breaks down for atmospheric hydrogen mixing ratios <1 ppm, resulting in ~40% of the atmospheric CO_2 being converted to CO and O_2 on a timescale of 1 Myr. The increased O_2 abundance leads to high O_3 concentrations, the photolysis of which forms another CO_2-regenerating catalytic cycle. For atmospheres with <0.1 ppm hydrogen, CO_2 is produced directly from the recombination of CO and O. These catalytic cycles place an upper limit of ~50% on the amount of CO_2 that can be destroyed via photolysis, which is enough to generate Earth-like abundances of (abiotic) O_2 and O_3. The conditions that lead to such high oxygen levels could be widespread on planets in the habitable zones of M dwarfs. Discrimination between biological and abiotic O_2 and O_3 in this case can perhaps be accomplished by noting the lack of water features in the reflectance and emission spectra of these planets, which necessitates observations at wavelengths longer than 0.95 \u03bcm.", "date": "2015-06-20", "date_type": "published", "publication": "Astrophysical Journal", "volume": "806", "number": "2", "publisher": "American Astronomical Society", "pagerange": "Art. No. 249", "id_number": "CaltechAUTHORS:20150805-084428243", "issn": "0004-637X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150805-084428243", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NNX10AP80G" }, { "agency": "NASA", "grant_number": "NNH12ZDA002C" }, { "agency": "NASA", "grant_number": "NNA13AA93A" }, { "agency": "NASA Hubble Fellowship", "grant_number": "51332" }, { "agency": "NASA", "grant_number": "NAS 5-26555" }, { "agency": "NASA/JPL/Caltech" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1088/0004-637X/806/2/249", "primary_object": { "basename": "0004-637X_806_2_249.pdf", "url": "https://authors.library.caltech.edu/records/c805t-23f68/files/0004-637X_806_2_249.pdf" }, "related_objects": [ { "basename": "1501.06876.pdf", "url": "https://authors.library.caltech.edu/records/c805t-23f68/files/1501.06876.pdf" } ], "resource_type": "article", "pub_year": "2015", "author_list": "Gao, Peter; Hu, Renyu; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/mh87h-ytv44", "eprint_id": 85258, "eprint_status": "archive", "datestamp": "2023-09-15 05:52:46", "lastmod": "2023-10-23 21:21:45", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Jiang-Xun", "name": { "family": "Jiang", "given": "Xun" }, "orcid": "0000-0001-8932-3807" }, { "id": "Olsen-E-T", "name": { "family": "Olsen", "given": "Edward T." } }, { "id": "Pagano-T-S", "name": { "family": "Pagano", "given": "Thomas S." } }, { "id": "Su-Hui", "name": { "family": "Su", "given": "Hui" }, "orcid": "0000-0003-1265-9702" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Modulation of Midtropospheric CO_2 by the South Atlantic Walker Circulation", "ispublished": "pub", "full_text_status": "public", "keywords": "Walker circulation; Carbon cycle; Carbon dioxide", "note": "\u00a9 2015 American Meteorological Society. \n\nManuscript received 19 November 2014, in final form 19 February 2015. \n\nWe thank two anonymous reviewers for helpful comments. XJ and YLY were supported by the AIRS project, OCO-2 project, and NASA Grant NNX13AC04G to UH and Caltech. Part of this research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration.\n\nPublished - jas-d-14-0340.1.pdf
Supplemental Material - 10.1175_jas-d-14-0340.s1.doc
", "abstract": "Midtropospheric CO_2 data from the Atmospheric Infrared Sounder (AIRS) are used in this study to explore the variability of CO_2 over the South Atlantic Ocean. It was found that the area-averaged CO_2 over the South Atlantic Ocean is less than that over South America by about 1 ppm during December\u2013March. This CO_2 contrast is due to the large-scale vertical circulation over this region. During December\u2013March, there is sinking motion over the South Atlantic Ocean. The sinking motion brings high-altitude air with a slightly lower concentration of CO_2 to the midtroposphere. Meanwhile, air rising over South America brings near-surface air with a higher concentration of CO_2 to the midtroposphere. As a result, the AIRS midtropospheric CO_2 concentration is lower over the South Atlantic Ocean than over South America during December\u2013March. The detrended AIRS midtropospheric CO_2 difference correlates well with the inverted and detrended 400-hPa vertical pressure velocity difference between the South Atlantic and South America. Results obtained from this study demonstrate the strong impact of large-scale circulation on the vertical distribution of CO_2 in the free troposphere and suggest that midtropospheric CO_2 measurements can be used as an innovative observational constraint on the simulation of large-scale circulations in climate models.", "date": "2015-06", "date_type": "published", "publication": "Journal of the Atmospheric Sciences", "volume": "72", "number": "6", "publisher": "American Meteorological Society", "pagerange": "2241-2247", "id_number": "CaltechAUTHORS:20180312-144301289", "issn": "0022-4928", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180312-144301289", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "AIRS project" }, { "agency": "Orbiting Carbon Observatory 2 (OCO-2)" }, { "agency": "NASA", "grant_number": "NNX13AC04G" }, { "agency": "NASA/JPL/Caltech" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1175/JAS-D-14-0340.1", "primary_object": { "basename": "10.1175_jas-d-14-0340.s1.doc", "url": "https://authors.library.caltech.edu/records/mh87h-ytv44/files/10.1175_jas-d-14-0340.s1.doc" }, "related_objects": [ { "basename": "jas-d-14-0340.1.pdf", "url": "https://authors.library.caltech.edu/records/mh87h-ytv44/files/jas-d-14-0340.1.pdf" } ], "resource_type": "article", "pub_year": "2015", "author_list": "Jiang, Xun; Olsen, Edward T.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/9vkrz-q0978", "eprint_id": 57770, "eprint_status": "archive", "datestamp": "2023-08-22 15:22:47", "lastmod": "2023-10-23 17:44:19", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Li-Cheng", "name": { "family": "Li", "given": "Cheng" }, "orcid": "0000-0002-8280-3119" }, { "id": "Zhang-Xi", "name": { "family": "Zhang", "given": "Xi" } }, { "id": "Gao-Peter", "name": { "family": "Gao", "given": "Peter" }, "orcid": "0000-0002-8518-9601" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk" }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Vertical Distribution of C_3-hydrocarbons in the Stratosphere of Titan", "ispublished": "pub", "full_text_status": "public", "keywords": "astrochemistry; planets and satellites: atmospheres; planets and satellites: composition; planets and satellites: individual (Titan)", "note": "\u00a9 2015 The American Astronomical Society.\n\nReceived 9 January 2015; accepted for publication 23 March 2015; published 15 April 2015.\n\nThis research was supported in part by NASA grants\nNNX09AB72G and Cassini UVIS program grant JPL.1459109\nto the California Institute of Technology. X.Z. was supported\nby the Bisgrove Scholar Program at the University of Arizona.\nY.L.Y. was supported in part by the NAI on Titan\nAstrobiology.\n\nPublished - 2041-8205_803_2_L19.pdf
", "abstract": "Motivated by the recent detection of propene (C_3H_6) in the atmosphere of Titan, we use a one-dimensional Titan photochemical model with an updated eddy diffusion profile to systematically study the vertical profiles of the stable species in the C_3-hydrocarbon family. We find that the stratospheric volume mixing ratio of propene (C_3H_6) peaks at 150 km with a value of 5 \u00d7 10^(\u22129), which is in good agreement with recent observations by the Composite Infrared Spectrometer on the Cassini spacecraft. Another important species that is currently missing from the hydrocarbon family in Titan's stratosphere is allene (CH_2CCH_2), an isomer of methylacetylene (CH_3C_2H). We predict that its mixing ratio in the stratosphere is about 10^(\u22129), which is on the margin of the detection limit. CH_2CCH_2 and CH_3C_2H equilibrate at a constant ratio in the stratosphere by hydrogen-exchanging reactions. Thus, by precisely measuring the ratio of CH_2CCH_2 to CH_3C_2H, the abundance of atomic hydrogen in the atmosphere can be inferred. No direct yield for the production of cyclopropane (c-C_3H_6) is available. From the discharge experiments of Navarro-Gonz\u00e1lez & Ram\u00edrez, the abundance of cyclopropane is estimated to be 100 times less than that of C_3H_6.", "date": "2015-04-20", "date_type": "published", "publication": "Astrophysical Journal Letters", "volume": "803", "number": "2", "publisher": "American Astronomical Society", "pagerange": "Art. No. L19", "id_number": "CaltechAUTHORS:20150522-095721836", "issn": "2041-8205", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150522-095721836", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NNX09AB72G" }, { "agency": "Cassini UVIS Program", "grant_number": "JPL.1459109" }, { "agency": "University of Arizona Bisgrove Scholar Program" }, { "agency": "NAI on Titan Astrobiology" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1088/2041-8205/803/2/L19", "primary_object": { "basename": "2041-8205_803_2_L19.pdf", "url": "https://authors.library.caltech.edu/records/9vkrz-q0978/files/2041-8205_803_2_L19.pdf" }, "resource_type": "article", "pub_year": "2015", "author_list": "Li, Cheng; Zhang, Xi; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/6k2rw-4me98", "eprint_id": 47155, "eprint_status": "archive", "datestamp": "2023-08-22 14:44:06", "lastmod": "2023-10-26 20:21:35", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Wong-Michael-L", "name": { "family": "Wong", "given": "Michael L." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Gladstone-G-R", "name": { "family": "Gladstone", "given": "G. Randall" } } ] }, "title": "Pluto's implications for a Snowball Titan", "ispublished": "pub", "full_text_status": "restricted", "keywords": "Pluto, atmosphere; Titan, atmosphere; Pluto; Titan; Photochemistry", "note": "\u00a9 2014 Elsevier Inc. \n\nReceived 22 January 2014, Revised 21 April 2014, Accepted 14 May 2014, Available online 3 June 2014. \n\nThis research was supported in part by the Cassini UVIS program via NASA Grant JPL.1459109, NASA NNX09AB72G grant to the California Institute of Technology. YLY was supported in part by the New Horizons Mission. We thank J. Kammer, C. Li, P. Gao, P. Kopparla, X. Zhang, D. Piskorz, and H. Ngo for helpful comments. Special thanks are due to C. Sotin for making available their model prior to publication. We are grateful for the comments and suggestions from our two anonymous reviewers.", "abstract": "The current Cassini\u2013Huygens Mission to the Saturn system provides compelling evidence that the present state of Titan's dense atmosphere is unsustainable over the age of the Solar System. Instead, for most of its existence, Titan's atmosphere might have been in a Snowball state, characterized by a colder surface and a smaller amount of atmospheric CH_4, similar to that of Pluto or Triton. We run a 1-D chemical transport model and show that the rates of organic synthesis on a Snowball Titan are significantly slower than those on present-day Titan. The primary method of methane destruction\u2014photosensitized dissociation in the stratosphere\u2014is greatly dampened on Snowball Titan. The downward flux of higher-order molecules through the troposphere is dominated not by hydrocarbons such as ethane, as is the case on Titan today, but by nitriles. This result presents a testable observation that could confirm the Snowball Titan hypothesis. Because Pluto's atmosphere is similar to Titan's in composition, it serves as a basis for comparison. Future observations of Pluto by the New Horizons Mission will inform photochemical models of Pluto's atmosphere and can help us understand the photochemical nature of paleo-Titan's atmosphere.", "date": "2015-01-15", "date_type": "published", "publication": "Icarus", "volume": "246", "publisher": "Elsevier", "pagerange": "192-196", "id_number": "CaltechAUTHORS:20140714-081046063", "issn": "0019-1035", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140714-081046063", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "JPL.1459109" }, { "agency": "NASA", "grant_number": "NNX09AB72G" }, { "agency": "New Horizons Mission" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/j.icarus.2014.05.019", "resource_type": "article", "pub_year": "2015", "author_list": "Wong, Michael L.; Yung, Yuk L.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/dje7q-mqy33", "eprint_id": 90300, "eprint_status": "archive", "datestamp": "2023-08-20 04:35:11", "lastmod": "2023-10-18 23:21:29", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Wong-Kam-Weng", "name": { "family": "Wong", "given": "K. W." } }, { "id": "Fu-Dejian", "name": { "family": "Fu", "given": "D." } }, { "id": "Pongetti-T-J", "name": { "family": "Pongetti", "given": "T. J." }, "orcid": "0000-0001-9465-0853" }, { "id": "Newman-S", "name": { "family": "Newman", "given": "S." }, "orcid": "0000-0003-0710-995X" }, { "id": "Kort-E-A", "name": { "family": "Kort", "given": "E. A." }, "orcid": "0000-0003-4940-7541" }, { "id": "Duren-R-M", "name": { "family": "Duren", "given": "R." }, "orcid": "0000-0003-4723-5280" }, { "id": "Hsu-Ying-Kuang", "name": { "family": "Hsu", "given": "Y.-K." } }, { "id": "Miller-C-E", "name": { "family": "Miller", "given": "C. E." }, "orcid": "0000-0002-9380-4838" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Y. L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Sander-S-P", "name": { "family": "Sander", "given": "S. P." }, "orcid": "0000-0003-1424-3620" } ] }, "title": "Mapping CH_4 : CO_2 ratios in Los Angeles with CLARS-FTS from Mount Wilson, California", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 Author(s) 2015. This work is distributed under the Creative Commons Attribution 3.0 License. \n\nReceived: 23 May 2014 \u2013 Discussion started: 26 Jun 2014 \u2013 Revised: 16 Sep 2014 \u2013 Accepted: 18 Oct 2014 \u2013 Published: 12 Jan 2015. \n\nThe authors thank our colleagues at JPL, Q. Zhang (California Institute of Technology), D. Wunch (California Institute of Technology), P. Wennberg (California Institute of Technology), C. Roehl (California Institute of Technology), J. Stutz (University of California, Los Angeles) and G. Keppel-Aleks (University of Michigan) for helpful comments. Support from the\nNASA Postdoctoral Program, California Air Resources Board, NOAA Climate Program, NIST GHG and Climate Science Program and JPL Earth Science and Technology Directorate is gratefully acknowledged. Y. L. Yung was supported in part by NASA grant NNX13AK34G to the California Institute of Technology and the KISS program of Caltech. \n\nEdited by: R. Harley\n\nPublished - acp-15-241-2015.pdf
", "abstract": "The Los Angeles megacity, which is home to more than 40% of the population in California, is the second largest megacity in the United States and an intense source of anthropogenic greenhouse gases (GHGs). Quantifying GHG emissions from the megacity and monitoring their spatiotemporal trends are essential to be able to understand the effectiveness of emission control policies. Here we measure carbon dioxide (CO_2) and methane (CH_4) across the Los Angeles megacity using a novel approach \u2013 ground-based remote sensing from a mountaintop site. A Fourier transform spectrometer (FTS) with agile pointing optics, located on Mount Wilson at 1.67 km above sea level, measures reflected near-infrared sunlight from 29 different surface targets on Mount Wilson and in the Los Angeles megacity to retrieve the slant column abundances of CO_2, CH_4 and other trace gases above and below Mount Wilson. This technique provides persistent space- and time-resolved observations of path-averaged dry-air GHG concentrations, XGHG, in the Los Angeles megacity and simulates observations from a geostationary satellite. In this study, we combined high-sensitivity measurements from the FTS and the panorama from Mount Wilson to characterize anthropogenic CH_4 emissions in the megacity using tracer\u2013tracer correlations. During the period between September 2011 and October 2013, the observed XCH_4 : XCO_2 excess ratio, assigned to anthropogenic activities, varied from 5.4 to 7.3 ppb CH_4 (ppm CO_2)^(\u22121), with an average of 6.4 \u00b1 0.5 ppb CH_4 (ppm CO_2)^(\u22121) compared to the value of 4.6 \u00b1 0.9 ppb CH_4 (ppm CO_2)^(\u22121) expected from the California Air Resources Board (CARB) bottom-up emission inventory. Persistent elevated XCH_4 : XCO_2 excess ratios were observed in Pasadena and in the eastern Los Angeles megacity. Using the FTS observations on Mount Wilson and the bottom-up CO_2 emission inventory, we derived a top-down CH_4 emission of 0.39 \u00b1 0.06 Tg CH_4 year^(\u22121) in the Los Angeles megacity. This is 18\u201361% larger than the state government's bottom-up CH_4 emission inventory and consistent with previous studies.", "date": "2015-01-12", "date_type": "published", "publication": "Atmospheric Chemistry and Physics", "volume": "15", "number": "1", "publisher": "European Geosciences Union", "pagerange": "241-252", "id_number": "CaltechAUTHORS:20181016-153903592", "issn": "1680-7316", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20181016-153903592", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA Postdoctoral Program" }, { "agency": "California Air Resources Board" }, { "agency": "National Oceanic and Atmospheric Administration (NOAA)" }, { "agency": "National Institute of Standards and Technology (NIST)" }, { "agency": "JPL" }, { "agency": "NASA", "grant_number": "NNX13AK34G" }, { "agency": "Keck Institute for Space Studies (KISS)" } ] }, "local_group": { "items": [ { "id": "Keck-Institute-for-Space-Studies" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/acp-15-241-2015", "primary_object": { "basename": "acp-15-241-2015.pdf", "url": "https://authors.library.caltech.edu/records/dje7q-mqy33/files/acp-15-241-2015.pdf" }, "resource_type": "article", "pub_year": "2015", "author_list": "Wong, K. W.; Fu, D.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/sm04p-wn879", "eprint_id": 53775, "eprint_status": "archive", "datestamp": "2023-08-22 14:31:39", "lastmod": "2023-10-19 22:12:22", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Shemansky-D-E", "name": { "family": "Shemansky", "given": "D. E." }, "orcid": "0000-0001-7168-871X" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Y. L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Liu-X", "name": { "family": "Liu", "given": "X." } }, { "id": "Yoshii-J", "name": { "family": "Yoshii", "given": "J." } }, { "id": "Hansen-C-J", "name": { "family": "Hansen", "given": "C. J." } }, { "id": "Hendrix-A-R", "name": { "family": "Hendrix", "given": "A. R." } }, { "id": "Exposito-L-W", "name": { "family": "Esposito", "given": "L. W." } } ] }, "title": "A New Understanding of the Europa Atmosphere and Limits on Geophysical Activity", "ispublished": "pub", "full_text_status": "public", "keywords": "atomic processes; molecular processes; planetary systems; plasmas", "note": "\u00a9 2014 American Astronomical Society. Received 2014 August 28; accepted 2014 October 31; published 2014 December 2.\n\nThe authors thank Professor Wing-Huen Ip for critical comments\non the Galileo mission results at Jupiter. D.E.S., X.L.,\nJ.Y. and were partially supported by the Cassini UVIS program\nthrough contract to SET. Y.L.Y. was supported in part by the\nCassini UVIS program via NASA grant JPL.1459109 to the\nCalifornia Institute of Technology. C.J.H. and A.R.H. were partially supported by the Cassini UVIS program through contract to PSI. L.W.E. was partially supported by the Cassini UVIS contract to LASP.\n\nPublished - 0004-637X_797_2_84.pdf
", "abstract": "Deep extreme ultraviolet spectrograph exposures of the plasma sheet at the orbit of Europa, obtained in 2001 using the Cassini Ultraviolet Imaging Spectrograph experiment, have been analyzed to determine the state of the gas. The results are in basic agreement with earlier results, in particular with Voyager encounter measurements of electron density and temperature. Mass loading rates and lack of detectable neutrals in the plasma sheet, however, are in conflict with earlier determinations of atmospheric composition and density at Europa. A substantial fraction of the plasma species at the Europa orbit are long-lived sulfur ions originating at Io, with ~25% derived from Europa. During the outward radial diffusion process to the Europa orbit, heat deposition forces a significant rise in plasma electron temperature and latitudinal size accompanied with conversion to higher order ions, a clear indication that mass loading from Europa is very low. Analysis of far ultraviolet spectra from exposures on Europa leads to the conclusion that earlier reported atmospheric measurements have been misinterpreted. The results in the present work are also in conflict with a report that energetic neutral particles imaged by the Cassini ion and neutral camera experiment originate at the Europa orbit. An interpretation of persistent energetic proton pitch angle distributions near the Europa orbit as an effect of a significant population of neutral gas is also in conflict with the results of the present work. The general conclusion drawn here is that Europa is geophysically far less active than inferred in previous research, with mass loading of the plasma sheet \u22644.5 x 10^(25) atoms s^(-1) two orders of magnitude below earlier published calculations. Temporal variability in the region joining the Io and Europa orbits, based on the accumulated evidence, is forced by the response of the system to geophysical activity at Io. No evidence for the direct injection of H_2O into the Europa atmosphere or from Europa into the magnetosphere system, as has been observed at Enceladus in the Saturn system, is obtained in the present investigation.", "date": "2014-12-20", "date_type": "published", "publication": "Astrophysical Journal", "volume": "797", "number": "2", "publisher": "American Astronomical Society", "pagerange": "Art. No. 84", "id_number": "CaltechAUTHORS:20150115-103643143", "issn": "0004-637X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150115-103643143", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "JPL.1459109" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1088/0004-637X/797/2/84", "primary_object": { "basename": "0004-637X_797_2_84.pdf", "url": "https://authors.library.caltech.edu/records/sm04p-wn879/files/0004-637X_797_2_84.pdf" }, "resource_type": "article", "pub_year": "2014", "author_list": "Shemansky, D. E.; Yung, Y. L.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/dmg2k-war79", "eprint_id": 43264, "eprint_status": "archive", "datestamp": "2023-08-22 14:17:48", "lastmod": "2023-10-25 23:24:38", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Li-Cheng", "name": { "family": "Li", "given": "Cheng" }, "orcid": "0000-0002-8280-3119" }, { "id": "Zhang-Xi", "name": { "family": "Zhang", "given": "Xi" } }, { "id": "Kammer-J-A", "name": { "family": "Kammer", "given": "Joshua A." }, "orcid": "0000-0002-3441-3757" }, { "id": "Liang-Mao-Chang", "name": { "family": "Liang", "given": "Mao-Chang" }, "orcid": "0000-0002-5294-9344" }, { "id": "Shia-Run-Lie", "name": { "family": "Shia", "given": "Run-Lie" }, "orcid": "0000-0003-1911-3120" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "A non-monotonic eddy diffusivity profile of Titan's atmosphere revealed by Cassini observations", "ispublished": "pub", "full_text_status": "restricted", "keywords": "Titan photochemistry; Eddy diffusion profile; Chemical kinetics", "note": "\u00a9 2013 Published by Elsevier Ltd. Received 15 October 2013; Accepted 23 October 2013; Available online 23 November 2013.\n\nThis research was supported in part by the Cassini UVIS program via NASA grant JPL.1459109 to the California Institute of Technology. Y.L.Y., C.L. and X.Z. were supported in part by NASANNX09AB72G grant to the California Institute of Technology. Y.L.Y. was also supported in part by NAI via Dr. M. Allen of J.P.L. We thank Dr. M. Line for the discussion on the retrieval algorithm, Dr. P. Lavvas for giving us detailed aerosol parameters from his model and Dr. M. Gerstell for improving the paper.", "abstract": "Recent measurements from the limb-view soundings of Cassini/CIRS and the stellar occultations from Cassini/UVIS revealed the complete vertical profiles of minor species (e.g., C_2H_2 and C_2H_4) from 100 to 1000 km in the atmosphere of Titan. In this study, we developed an inversion technique to retrieve the eddy diffusion profile using C_2H_2 as a tracer species. The retrieved eddy profile features a low eddy diffusion zone near the altitude of the detached haze layer (~550 km), which could be a consequence of stabilization through aerosol heating. Photochemical modeling results using the retrieved eddy profile are in better agreement with the Cassini measurements than previous models. The underestimation of C_2H_4 in the stratosphere has been a long-standing problem in planetary photochemical modeling, and the new eddy diffusion profile does not solve this problem. In order to match the observations, we suggest a new expression for the rate coefficient of the key reaction, H + C_2H_4 + M\u27f6C_2H_5 + M. The new reaction rate coefficient is estimated to be ~10 times lower than that used by Moses et al. (2005)'s model, and should be validated in the laboratory and tested against the hydrocarbon chemistry of giant planets.", "date": "2014-12", "date_type": "published", "publication": "Planetary and Space Science", "volume": "104", "publisher": "Elsevier", "pagerange": "48-58", "id_number": "CaltechAUTHORS:20140108-110458449", "issn": "0032-0633", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140108-110458449", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "JPL.1459109" }, { "agency": "NASA", "grant_number": "NNX09AB72G" }, { "agency": "NAI" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/j.pss.2013.10.009", "resource_type": "article", "pub_year": "2014", "author_list": "Li, Cheng; Zhang, Xi; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/bkdr6-s2d89", "eprint_id": 91254, "eprint_status": "archive", "datestamp": "2023-08-22 14:17:08", "lastmod": "2023-10-19 22:20:37", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Liu-Chuanxi", "name": { "family": "Liu", "given": "Chuanxi" } }, { "id": "Tian-Baijun", "name": { "family": "Tian", "given": "Baijun" } }, { "id": "Li-King-Fai", "name": { "family": "Li", "given": "King-Fai" }, "orcid": "0000-0003-0150-2910" }, { "id": "Manney-G-L", "name": { "family": "Manney", "given": "Gloria L." } }, { "id": "Livesey-N-J", "name": { "family": "Livesey", "given": "Nathaniel J." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Waliser-D-E", "name": { "family": "Waliser", "given": "Duane E." } } ] }, "title": "Northern Hemisphere mid-winter vortex-displacement and vortex-split stratospheric sudden warmings: Influence of the Madden-Julian Oscillation and Quasi-Biennial Oscillation", "ispublished": "pub", "full_text_status": "public", "keywords": "Keywords\n\nstratospheric sudden warming; polar vortex; Madden\u2010Julian oscillation; quasi\u2010biennial oscillation; planetary wave; teleconnection", "note": "\u00a9 2014. American Geophysical Union. \n\nReceived 6 APR 2014. Accepted 10 OCT 2014. Accepted article online 13 OCT 2014. Published online 28 NOV 2014. \n\nThis research was supported by the National Science Foundation award ATM\u20100840755 to University of California, Los Angeles. Part of this research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration. KFL was supported by the Jack Eddy Fellowship, managed by the University Corporation for Atmospheric research. We thank George Kiladis and two anonymous reviewers for their helpful comments. We thank Guang J. Zhang for helpful discussions. The NCEP\u2010NCAR reanalysis data were kindly provided by the NOAA/OAR/ESRL\u2010PSD, Boulder, Colorado, from their website (http://www.esrl.noaa.gov/psd/).\n\nPublished - Liu_et_al-2014-Journal_of_Geophysical_Research_3A_Atmospheres.pdf
", "abstract": "We investigate the connection between the equatorial Madden\u2010Julian Oscillation (MJO) and different types of the Northern Hemisphere mid\u2010winter major stratospheric sudden warmings (SSWs), i.e., vortex\u2010displacement and vortex\u2010split SSWs. The MJO\u2010SSW relationship for vortex\u2010split SSWs is stronger than that for vortex\u2010displacement SSWs, as a result of the stronger and more coherent eastward propagating MJOs before vortex\u2010split SSWs than those before vortex\u2010displacement SSWs. Composite analysis indicates that both the intensity and propagation features of MJO may influence the MJO\u2010related circulation pattern at high latitudes and the type of SSWs. A pronounced Quasi\u2010Biennial Oscillation (QBO) dependence is found for vortex\u2010displacement and vortex\u2010split SSWs, with vortex\u2010displacement (\u2010split) SSWs occurring preferentially in easterly (westerly) QBO phases. The lagged composites suggest that the MJO\u2010related anomalies in the Arctic are very likely initiated when the MJO\u2010related convection is active over the equatorial Indian Ocean (around the MJO phase 3). Further analysis suggests that the QBO may modulate the MJO\u2010related wave disturbances via its influence on the upper tropospheric subtropical jet. As a result, the MJO\u2010related circulation pattern in the Arctic tends to be wave number\u2010one/wave number\u2010two ~25\u201330\u2009days following phase 3 (i.e., approximately phases 7\u20138, when the MJO\u2010related convection is active over the western Pacific) during easterly/westerly QBO phases, which resembles the circulation pattern associated with vortex\u2010displacement/vortex\u2010split SSWs.", "date": "2014-11-27", "date_type": "published", "publication": "Journal of Geophysical Research. Atmospheres", "volume": "119", "number": "22", "publisher": "American Geophysical Union", "pagerange": "12599-12620", "id_number": "CaltechAUTHORS:20181127-155643583", "issn": "2169-897X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20181127-155643583", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "ATM-0840755" }, { "agency": "NASA/JPL/Caltech" }, { "agency": "University Corporation for Atmospheric Research" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1002/2014jd021876", "primary_object": { "basename": "Liu_et_al-2014-Journal_of_Geophysical_Research_3A_Atmospheres.pdf", "url": "https://authors.library.caltech.edu/records/bkdr6-s2d89/files/Liu_et_al-2014-Journal_of_Geophysical_Research_3A_Atmospheres.pdf" }, "resource_type": "article", "pub_year": "2014", "author_list": "Liu, Chuanxi; Tian, Baijun; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/7f7e9-me065", "eprint_id": 48842, "eprint_status": "archive", "datestamp": "2023-08-22 14:07:46", "lastmod": "2023-10-17 20:28:38", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Boxe-C-S", "name": { "family": "Boxe", "given": "C. S." } }, { "id": "Francisco-J-S", "name": { "family": "Francisco", "given": "J. S." } }, { "id": "Shia-Run-Lie", "name": { "family": "Shia", "given": "R.-L." }, "orcid": "0000-0003-1911-3120" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Y. L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Nair-H-A", "name": { "family": "Nair", "given": "H." } }, { "id": "Liang-Mao-Chang", "name": { "family": "Liang", "given": "M.-C." }, "orcid": "0000-0002-5294-9344" }, { "id": "Saiz-Lopez-A", "name": { "family": "Saiz-Lopez", "given": "A." } } ] }, "title": "New Insights into Martian Atmospheric Chemistry", "ispublished": "pub", "full_text_status": "restricted", "keywords": "HOCO; CO2; Mars; Martian atmosphere", "note": "\u00a9 2014 Elsevier B.V. \n\nReceived Date: 4 May 2014. Revised Date: 18 July 2014. Accepted Date: 18 July 2014. In submission to Icarus.", "abstract": "HO_x radicals are produced in the Martian atmosphere by the photolysis of water vapor and subsequently participate in catalytic cycles that recycle carbon dioxide (CO_2) from its photolysis product carbon monoxide (CO), providing a qualitative explanation for the stability of its atmosphere. Balancing CO_2 production and loss based on our current understanding of Martian gas-phase chemistry has, however, proven to be difficult. The photolysis of O_3 produces O(^1D), while oxidation of CO produces HOCO radicals, a new member of the HO_x family. The O(^1D) quantum yield has recently been updated, which quantifies nonzero quantum yields in the Huggins bands. In Earth's atmosphere HOCO is considered to be unimportant since it is quickly removed by abundant oxygen molecules. The smaller amount of O_2 in the Mars' atmosphere causes HOCO's lifetime to be longer in Mars' atmosphere than Earth's (3 \u00d7 10^(-5) seconds to 1.2 days from Mars's surface to 240 km, respectively). Limited kinetic data on reactions involving HOCO prevented consideration of its reactions directly in atmospheric models. Therefore, the impact of HOCO reactions on Martian chemistry is currently unknown. Here, we incorporate new literature rate constants for HOCO chemistry and an updated representation of the O(^1D) quantum yield in the Caltech/JPL 1-D photochemical model for Mars' atmosphere. Our simulations exemplify perturbations to NO_y, HO_x, and CO_x species, ranging from 5 to 50%. The modified O(^1D) quantum yield and new HOCO chemistry cause a 10% decrease and a 50% increase in OH and H_2O_2 total column abundances, respectively. At low altitudes, HOCO production contributes 5% towards CO_2 production. Given recent experimentally-obtained branching ratios for the oxidation of CO, HOCO may contribute up to 70% toward the production of NO_y, where HO_x and NO_y species are enhanced up to a factor 3, which has implications for rethinking the fundamental understanding of NO_y, HO_x, and CO/CO_2 cycling on Mars. Two new reaction mechanisms for converting CO to CO_2 using HOCO reactions are proposed, which reveal that H_2O_2 is more intimately coupled to CO_x chemistry. Our simulations are in good agreement with satellite/spacecraft measurements of CO and H_2O_2 on Mars.", "date": "2014-11-01", "date_type": "published", "publication": "Icarus", "volume": "242", "publisher": "Elsevier", "pagerange": "97-104", "id_number": "CaltechAUTHORS:20140825-101937055", "issn": "0019-1035", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140825-101937055", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/j.icarus.2014.07.023", "resource_type": "article", "pub_year": "2014", "author_list": "Boxe, C. S.; Francisco, J. S.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/9kp6e-35f29", "eprint_id": 48800, "eprint_status": "archive", "datestamp": "2023-08-22 08:08:17", "lastmod": "2023-10-17 20:26:32", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Shia-Run-Lie", "name": { "family": "Shia", "given": "Run-Lie" }, "orcid": "0000-0003-1911-3120" }, { "id": "Kuai-Le", "name": { "family": "Kuai", "given": "Le" }, "orcid": "0000-0001-6406-1150" }, { "id": "Line-M-R", "name": { "family": "Line", "given": "Michael R." }, "orcid": "0000-0002-2338-476X" }, { "id": "Trauger-J-T", "name": { "family": "Trauger", "given": "John T." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Pressure Line Broadening and Feasibility of CO_2 Profile Retrieval using Near Infrared Observations of an Absorption Line", "ispublished": "unpub", "full_text_status": "public", "note": "We thank Dr. J. Margolis for his valuable suggestions on the noise-resolution\nrelation for instruments, Dr. V. Natraj for helpful comments and GOSAT retrieval data and Dr. S.\nNewman for her suggestions to improve the manuscript. This research is supported in part by the\nOrbiting Carbon Observatory 2 (OCO-2) project, a NASA Earth System Science Pathfinder\n(ESSP) mission and Project JPL.1382974 to the California Institute of Technology.\n\nDraft - Shia_2013_1-line_Jan7.pdf
", "abstract": "Analytic expressions are derived for the transmittance and reflectance of sunlight and\ntheir Jacobians for an absorption line with Lorentz line broadening. Rodgers information analysis\nis applied to calculate the information content, the degrees of freedom and the averaging kernel\nfor a simple atmospheric model to investigate the feasibility of retrieving the profile of CO_2\nusing near-infrared (NIR) measurements over a single absorption line. The results have\nimplications for the design of future space instruments with high spectral resolution and high\nsignal to noise ratios to obtain global scale information on the CO_2 vertical distribution which is\nimportant for inferring the sources, sinks, and transport of CO_2.", "date": "2014-08-25", "date_type": "published", "publisher": "Caltech Library", "id_number": "CaltechAUTHORS:20140822-092102214", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140822-092102214", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA Orbiting Carbon Observatory 2 (OCO-2) Project" }, { "agency": "JPL", "grant_number": "JPL.1382974" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "primary_object": { "basename": "Shia_2013_1-line_Jan7.pdf", "url": "https://authors.library.caltech.edu/records/9kp6e-35f29/files/Shia_2013_1-line_Jan7.pdf" }, "resource_type": "monograph", "pub_year": "2014", "author_list": "Shia, Run-Lie; Kuai, Le; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/011gv-njr47", "eprint_id": 48827, "eprint_status": "archive", "datestamp": "2023-08-22 12:44:52", "lastmod": "2023-10-17 20:27:46", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Su-Hui", "name": { "family": "Su", "given": "Hui" } }, { "id": "Jiang-Jonathan-H", "name": { "family": "Jiang", "given": "Jonathan H." }, "orcid": "0000-0002-5929-8951" }, { "id": "Zhai-Chengxing", "name": { "family": "Zhai", "given": "Chengxing" }, "orcid": "0000-0002-0291-4522" }, { "id": "Shen-Tsaepyng-J", "name": { "family": "Shen", "given": "Tsaepyng J." } }, { "id": "Neelin-J-David", "name": { "family": "Neelin", "given": "J. David" }, "orcid": "0000-0001-9414-9962" }, { "id": "Stephens-Graeme-L", "name": { "family": "Stephens", "given": "Graeme L." }, "orcid": "0000-0002-9860-0287" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Weakening and strengthening structures in the Hadley Circulation change under global warming and implications for cloud response and climate sensitivity", "ispublished": "pub", "full_text_status": "public", "keywords": "global warming; cloud feedback; climate sensitivity; satellite observations; the Hadley Circulation; model performance metrics", "note": "\u00a9 2014 American Geophysical Union. Received 12 Feb 2014. \nAccepted 26 Apr 2014. Accepted article online 4 May 2014.\nPublished online 20 May 2014. We are thankful to Jay Mace, Eric J. Fetzer, and William G. Read for helpful discussions of data quality. Discussions with Kevin Bowman, Duane Waliser, and Michael Gunson are appreciated. This paper is greatly improved owing to the detailed comments and constructive suggestions by Mark Zelinka and two other reviewers. We acknowledge the World Climate Research Programme's Working Group on Coupled Modelling, which is responsible for CMIP. We thank the climate modeling groups listed in Table 1 for producing and making available their model output. The U.S. Department of Energy (DOE) Program\nfor Climate Model Diagnosis and Intercomparison provides coordinating support and led development of software\ninfrastructure in partnership with the Global Organization for Earth System Science Portals. The A-Train satellite data are available at NASA Distributed Active Archive Centers (DAAC). H.S., J.H.J., C.Z., and J.T.S. acknowledge funding support from NASA NEWS, COUND, and AST programs\nand Aura MLS and CloudSat projects. J.D.N. was supported by NOAA NA11OAR4310099 and NSF AGS-1102838. Y.L.Y. was supported by UHOUST.130027 subcontract from the University of Houston. This work was performed at Jet Propulsion Laboratory, California Institute of Technology, under\ncontract with NASA.\n\nPublished - jgrd51405.pdf
", "abstract": "It has long been recognized that differences in climate model-simulated cloud feedbacks are a primary source of uncertainties for the model-predicted surface temperature change induced by increasing greenhouse gases such as CO_2. Large-scale circulation broadly determines when and where clouds form and how they evolve. However, the linkage between large-scale circulation change and cloud radiative effect (CRE) change under global warming has not been thoroughly studied. By analyzing 15 climate models, we show that the change of the Hadley Circulation exhibits meridionally varying weakening and strengthening structures, physically consistent with the cloud changes in distinct cloud regimes. The regions that experience a weakening (strengthening) of the zonal-mean circulation account for 54% (46%) of the multimodel-mean top-of-atmosphere (TOA) CRE change integrated over 45\u00b0S\u201340\u00b0N. The simulated Hadley Circulation structure changes per degree of surface warming differ greatly between the models, and the intermodel spread in the Hadley Circulation change is well correlated with the intermodel spread in the TOA CRE change. This correlation underscores the close interactions between large-scale circulation and clouds and suggests that the uncertainties of cloud feedbacks and climate sensitivity reside in the intimate coupling between large-scale circulation and clouds. New model performance metrics proposed in this work, which emphasize how models reproduce satellite-observed spatial variations of zonal-mean cloud fraction and relative humidity associated with the Hadley Circulation, indicate that the models closer to the satellite observations tend to have equilibrium climate sensitivity higher than the multimodel mean.", "date": "2014-05-27", "date_type": "published", "publication": "Journal of Geophysical Research. Atmospheres", "volume": "119", "number": "10", "publisher": "American Geophysical Union", "pagerange": "5787-5805", "id_number": "CaltechAUTHORS:20140825-071722815", "issn": "2169-897X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140825-071722815", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "National Oceanic and Atmospheric Administration (NOAA)", "grant_number": "NA11OAR4310099" }, { "agency": "NSF", "grant_number": "AGS-102838" }, { "agency": "University of Houston", "grant_number": "UHOUST.130027" }, { "agency": "NASA/JPL/Caltech" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1002/2014JD021642", "primary_object": { "basename": "jgrd51405.pdf", "url": "https://authors.library.caltech.edu/records/011gv-njr47/files/jgrd51405.pdf" }, "resource_type": "article", "pub_year": "2014", "author_list": "Su, Hui; Jiang, Jonathan H.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/z5mph-1ys91", "eprint_id": 48829, "eprint_status": "archive", "datestamp": "2023-09-15 04:49:38", "lastmod": "2023-10-23 21:10:22", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Hearty-T-J", "name": { "family": "Hearty", "given": "Thomas J." } }, { "id": "Savtchenko-A", "name": { "family": "Savtchenko", "given": "Andrew" } }, { "id": "Tian-Baijun", "name": { "family": "Tian", "given": "Baijun" } }, { "id": "Fetzer-E-J", "name": { "family": "Fetzer", "given": "Eric" } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Theobald-M", "name": { "family": "Theobald", "given": "Michael" } }, { "id": "Vollmer-B", "name": { "family": "Vollmer", "given": "Bruce" } }, { "id": "Fishbein-E", "name": { "family": "Fishbein", "given": "Evan" } }, { "id": "Won-Y-I", "name": { "family": "Won", "given": "Young-In" } } ] }, "title": "Estimating sampling biases and measurement uncertainties of AIRS/AMSU-A temperature and water vapor observations using MERRA reanalysis", "ispublished": "pub", "full_text_status": "public", "keywords": "AIRS/AMSU-A; climatology; sampling; MERRA; temperature; water vapor", "note": "\u00a9 2014 American Geophysical Union. Received 14 Nov 2013.\nAccepted 11 Feb 2014. Accepted article online 14 Feb 2014. Published online 18 Mar 2014. T.H. wishes to acknowledge conversations with Gregory Leptoukh as an early impetus for this work. Also, Ron Gelaro, Mike Bosilovich, Peter Smith, and Dana Ostrenga provided insights into the MERRA data. Glynn Hulley, Suhung Shen, and Zhanqing Li helped us to understand some of the atmospheric and surface phenomena\ndiscussed in this paper. John Blaisdel and Joel Susskind helped us to understand aspects of the AIRS/AMSU-A\nretrieval algorithm relevant to this study. We also acknowledge three anonymous referees who helped us to improve this paper and suggested ideas for future studies. Part of this research was performed at the Jet Propulsion Laboratory (JPL), California Institute of Technology (Caltech), under a contract with the National Aeronautics and Space Administration (NASA). The AIRS/AMSU-A and MERRA\ndata presented in this paper are available from Goddard Earth Sciences Data and Information Services Center\n(GES DISC; disc.gsfc.nasa.gov).\n\nPublished - jgrd51224.pdf
Supplemental Material - README.doc
Supplemental Material - airs_sampling_finalfs01.jpg
Supplemental Material - airs_sampling_finalfs02.jpg
Supplemental Material - airs_sampling_finalfs03.jpg
Supplemental Material - airs_sampling_finalfs04.jpg
Supplemental Material - airs_sampling_finalfs05.jpg
", "abstract": "We use MERRA (Modern Era Retrospective-Analysis for Research Applications) temperature and water vapor data to estimate the sampling biases of climatologies derived from the AIRS/AMSU-A (Atmospheric Infrared Sounder/Advanced Microwave Sounding Unit-A) suite of instruments. We separate the total sampling bias into temporal and instrumental components. The temporal component is caused by the AIRS/AMSU-A orbit and swath that are not able to sample all of time and space. The instrumental component is caused by scenes that prevent successful retrievals. The temporal sampling biases are generally smaller than the instrumental sampling biases except in regions with large diurnal variations, such as the boundary layer, where the temporal sampling biases of temperature can be \u00b1 2 K and water vapor can be 10% wet. The instrumental sampling biases are the main contributor to the total sampling biases and are mainly caused by clouds. They are up to 2 K cold and > 30% dry over midlatitude storm tracks and tropical deep convective cloudy regions and up to 20% wet over stratus regions. However, other factors such as surface emissivity and temperature can also influence the instrumental sampling bias over deserts where the biases can be up to 1 K cold and 10% wet. Some instrumental sampling biases can vary seasonally and/or diurnally. We also estimate the combined measurement uncertainties of temperature and water vapor from AIRS/AMSU-A and MERRA by comparing similarly sampled climatologies from both data sets. The measurement differences are often larger than the sampling biases and have longitudinal variations.", "date": "2014-03-27", "date_type": "published", "publication": "Journal of Geophysical Research. Atmospheres", "volume": "119", "number": "6", "publisher": "American Geophysical Union", "pagerange": "2725-2741", "id_number": "CaltechAUTHORS:20140825-081520508", "issn": "2169-897X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140825-081520508", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA/JPL/Caltech" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1002/2013JD021205", "primary_object": { "basename": "airs_sampling_finalfs03.jpg", "url": "https://authors.library.caltech.edu/records/z5mph-1ys91/files/airs_sampling_finalfs03.jpg" }, "related_objects": [ { "basename": "airs_sampling_finalfs04.jpg", "url": "https://authors.library.caltech.edu/records/z5mph-1ys91/files/airs_sampling_finalfs04.jpg" }, { "basename": "airs_sampling_finalfs05.jpg", "url": "https://authors.library.caltech.edu/records/z5mph-1ys91/files/airs_sampling_finalfs05.jpg" }, { "basename": "jgrd51224.pdf", "url": "https://authors.library.caltech.edu/records/z5mph-1ys91/files/jgrd51224.pdf" }, { "basename": "README.doc", "url": "https://authors.library.caltech.edu/records/z5mph-1ys91/files/README.doc" }, { "basename": "airs_sampling_finalfs01.jpg", "url": "https://authors.library.caltech.edu/records/z5mph-1ys91/files/airs_sampling_finalfs01.jpg" }, { "basename": "airs_sampling_finalfs02.jpg", "url": "https://authors.library.caltech.edu/records/z5mph-1ys91/files/airs_sampling_finalfs02.jpg" } ], "resource_type": "article", "pub_year": "2014", "author_list": "Hearty, Thomas J.; Savtchenko, Andrew; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/qwya2-tkq42", "eprint_id": 41912, "eprint_status": "archive", "datestamp": "2023-08-22 11:56:07", "lastmod": "2024-02-02 21:11:24", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Line-M-R", "name": { "family": "Line", "given": "Michael R." }, "orcid": "0000-0002-2338-476X" }, { "id": "Knutson-H-A", "name": { "family": "Knutson", "given": "Heather" }, "orcid": "0000-0002-5375-4725" }, { "id": "Wolf-A-S", "name": { "family": "Wolf", "given": "Aaron S." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "A Systematic Retrieval Analysis of Secondary Eclipse Spectra. II. A Uniform Analysis of Nine Planets and their C to O Ratios", "ispublished": "pub", "full_text_status": "public", "keywords": "methods: statistical; planets and satellites: atmospheres; planets and satellites: composition; planets and satellites: gaseous planets; planets and satellites: individual (HD 189733b, HD 149026b, GJ436b, WASP-12b, WASP-19b, WASP-43b, TrES-2b, TrES-3b)", "note": "\u00a9 2014 American Astronomical Society. \n\nReceived 2013 September 26; accepted 2014 January 21; published 2014 February 14. \n\nWe thank Jonathan Fortney, Rob Zellum, Xi Zhang, Nikku Madahusudhan, Caroline Morely, and Jonathan Frain for insightful conversations. This research was supported in part by an NAI Virtual Planetary Laboratory grant from the University of Washington to the Jet Propulsion Laboratory and California Institute of Technology.\n\nPublished - 0004-637X_783_2_70.pdf
Submitted - 1309.6663.pdf
", "abstract": "Secondary eclipse spectroscopy provides invaluable insights into the temperatures and compositions of exoplanetary atmospheres. We carry out a systematic temperature and abundance retrieval analysis of nine exoplanets (HD 189733b, HD 209458b, HD 149026b, GJ436b, WASP-12b, WASP-19b, WASP-43b, TrES-2b, and TrES-3b) observed in secondary eclipse using a combination of space- and ground-based facilities. Our goal with this analysis is to provide a consistent set of temperatures and compositions from which self-consistent models can be compared and to probe the underlying processes that shape these atmospheres. This paper is the second in a three part series of papers exploring the retrievability of temperatures and abundances from secondary eclipse spectra and the implications of these results for the chemistry of exoplanet atmospheres. In this investigation we present a catalogue of temperatures and abundances for H_2O, CH_4, CO, and CO_2. We find that our temperatures and abundances are generally consistent with those of previous studies, although we do not find any statistically convincing evidence for super-solar C to O ratios (e.g., solar C/O falls in the 1\u03c3 confidence intervals in eight of the nine planets in our sample). Furthermore, within our sample we find little evidence for thermal inversions over a wide range of effective temperatures (with the exception of HD 209458b), consistent with previous investigations. The lack of evidence for inversions for most planets in our sample over such a wide range of effective temperatures provides additional support for the hypothesis that TiO is unlikely to be the absorber responsible for the formation of these inversions.", "date": "2014-03-10", "date_type": "published", "publication": "Astrophysical Journal", "volume": "783", "number": "2", "publisher": "American Astronomical Society", "pagerange": "Art. No. 70", "id_number": "CaltechAUTHORS:20131015-085300122", "issn": "0004-637X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20131015-085300122", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "University of Washington NAI Virtual Planetary Laboratory" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1088/0004-637X/783/2/70", "primary_object": { "basename": "0004-637X_783_2_70.pdf", "url": "https://authors.library.caltech.edu/records/qwya2-tkq42/files/0004-637X_783_2_70.pdf" }, "related_objects": [ { "basename": "1309.6663.pdf", "url": "https://authors.library.caltech.edu/records/qwya2-tkq42/files/1309.6663.pdf" } ], "resource_type": "article", "pub_year": "2014", "author_list": "Line, Michael R.; Knutson, Heather; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/yny6x-fgn13", "eprint_id": 43253, "eprint_status": "archive", "datestamp": "2023-08-22 11:53:10", "lastmod": "2023-10-25 23:24:08", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Gao-Peter", "name": { "family": "Gao", "given": "Peter" }, "orcid": "0000-0002-8518-9601" }, { "id": "Zhang-Xi", "name": { "family": "Zhang", "given": "Xi" } }, { "id": "Crisp-D", "name": { "family": "Crisp", "given": "David" }, "orcid": "0000-0002-4573-9998" }, { "id": "Bardeen-C-G", "name": { "family": "Bardeen", "given": "Charles G." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Bimodal Distribution of Sulfuric Acid Aerosols in the Upper Haze of Venus", "ispublished": "pub", "full_text_status": "public", "keywords": "Atmospheres, composition; Atmospheres, structure; Atmospheres, dynamics; Venus; Venus, atmosphere", "note": "\u00a9 2013 Elsevier Inc.\nReceived 5 March 2013;\nRevised 10 October 2013;\nAccepted 11 October 2013;\nAvailable online 29 October 2013.\n\nWe thank S. Garimella and R.L. Shia for assistance with the setting\nup and running of the CARMA code. We thank R.W. Carlson\nand C. Parkinson for their valuable inputs. We thank C. Li for his\nhelp in speeding up our model runs by more than a factor of 10.\nThis research was supported in part by the Venus Express program\nvia NASA NNX10AP80G grant to the California Institute of Technology,\nand in part by an NAI Virtual Planetary Laboratory grant from\nthe University of Washington to the Jet Propulsion Laboratory and\nCalifornia Institute of Technology. Part of the research described\nhere was carried out at the Jet Propulsion Laboratory, California\nInstitute of Technology, under a contract with the National Aeronautics\nand Space Administration.\n\nSubmitted - 1312.3750.pdf
", "abstract": "Observations by the SPICAV/SOIR instruments aboard Venus Express have revealed that the upper haze (UH) of Venus, between 70 and 90 km, is variable on the order of days and that it is populated by two particle modes. We use a one-dimensional microphysics and vertical transport model based on the Community Aerosol and Radiation Model for Atmospheres to evaluate whether interaction of upwelled cloud particles and sulfuric acid particles nucleated in situ on meteoric dust are able to generate the two observed modes, and whether their observed variability are due in part to the action of vertical transient winds at the cloud tops. Nucleation of photochemically produced sulfuric acid onto polysulfur condensation nuclei generates mode 1 cloud droplets, which then diffuse upwards into the UH. Droplets generated in the UH from nucleation of sulfuric acid onto meteoric dust coagulate with the upwelled cloud particles and therefore cannot reproduce the observed bimodal size distribution. By comparison, the mass transport enabled by transient winds at the cloud tops, possibly caused by sustained subsolar cloud top convection, are able to generate a bimodal size distribution in a time scale consistent with Venus Express observations. Below the altitude where the cloud particles are generated, sedimentation and vigorous convection causes the formation of large mode 2 and mode 3 particles in the middle and lower clouds. Evaporation of the particles below the clouds causes a local sulfuric acid vapor maximum that results in upwelling of sulfuric acid back into the clouds. In the case where the polysulfur condensation nuclei are small and their production rate is high, coagulation of small droplets onto larger droplets in the middle cloud may set up an oscillation in the size modes of the particles such that precipitation of sulfuric acid \"rain\" may be possible immediately below the clouds once every few Earth months. Reduction of the polysulfur condensation nuclei production rate destroys this oscillation and reduces the mode 1 particle abundance in the middle cloud by two orders of magnitude. However, it better reproduces the sulfur-to-sulfuric-acid mass ratio in the cloud and haze droplets as constrained by fits to UV reflectivity data. In general we find satisfactory agreement between our nominal and transient wind results and observations from Pioneer Venus, Venus Express, and Magellan, though improvements could be made by incorporating sulfur microphysics.", "date": "2014-03-01", "date_type": "published", "publication": "Icarus", "volume": "231", "publisher": "Elsevier", "pagerange": "83-98", "id_number": "CaltechAUTHORS:20140107-152003222", "issn": "0019-1035", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140107-152003222", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA Venus Express program", "grant_number": "NNX10AP80G" }, { "agency": "University of Washington NAI Virtual Planetary Laboratory grant" }, { "agency": "NASA/JPL/Caltech" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/j.icarus.2013.10.013", "primary_object": { "basename": "1312.3750.pdf", "url": "https://authors.library.caltech.edu/records/yny6x-fgn13/files/1312.3750.pdf" }, "resource_type": "article", "pub_year": "2014", "author_list": "Gao, Peter; Zhang, Xi; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/jf8gz-1q308", "eprint_id": 41917, "eprint_status": "archive", "datestamp": "2023-08-22 11:04:52", "lastmod": "2023-10-25 14:54:40", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Line-M-R", "name": { "family": "Line", "given": "Michael R." }, "orcid": "0000-0002-2338-476X" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "A Systematic Retrieval Analysis of Secondary Eclipse Spectra III: Diagnosing Chemical Disequilibrium in Planetary Atmospheres", "ispublished": "pub", "full_text_status": "public", "keywords": "astrochemistry; planets and satellites: atmospheres; planets and satellites: composition", "note": "\u00a9 2013 American Astronomical Society. Received 2013 September 25, accepted for publication 2013 October 25. Published 2013 November 14. We thank Dave Stevenson, Pin Chen, Gautam Vasisht,\nand Channon Visscher for useful discussions. We also\nthank Julie Moses and Jonathan Fortney as well as the\nYuk Yung group for meticulously reading the manuscript.\nThis research was supported in part by an NAI Virtual\nPlanetary Laboratory grant from the University of Washington to the Jet Propulsion Laboratory and California Institute of Technology. YLY was supported in part by NASA NNX09AB72G grant to the California Institute\nof Technology.\n\nPublished - 0004-637X_779_1_3.pdf
Submitted - 1309.6679v1.pdf
", "abstract": "Chemical disequilibrium has recently become a relevant topic in the study of the atmospheres of of transiting extrasolar planets, brown dwarfs, and directly imaged exoplanets. We present a new way of assessing whether or not a Jovian-like atmosphere is in chemical disequilibrium from observations of detectable or inferred gases such as H_2 O, CH_4, CO, and H _2. Our hypothesis, based on previous kinetic modeling studies, is that cooler atmospheres will show stronger signs of disequilibrium than hotter atmospheres. We verify this with chemistry-transport models and show that planets with temperatures less than ~ 1200 K are likely to show the strongest signs of disequilibrium due to the vertical quenching of CO, and that our new approach is able to capture this process. We also find that in certain instances a planetary composition may appear in equilibrium when it actually is not due to the degeneracy in the shape of the vertical mixing ratio profiles. We determine the state of disequilibrium in eight exoplanets using the results from secondary eclipse temperature and abundance retrievals. We find that all of the planets in our sample are consistent with thermochemical equilibrium to within 3-sigma. Future observations are needed to further constrain the abundances in order to definitively identify disequilibrium in exoplanet atmospheres.", "date": "2013-12-10", "date_type": "published", "publication": "Astrophysical Journal", "volume": "779", "number": "1", "publisher": "American Astronomical Society", "pagerange": "Art. No. 3", "id_number": "CaltechAUTHORS:20131015-104013706", "issn": "0004-637X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20131015-104013706", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "University of Washington NAI Virtual Planetary Laboratory" }, { "agency": "NASA", "grant_number": "NNX09AB72G" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1088/0004-637X/779/1/3", "primary_object": { "basename": "0004-637X_779_1_3.pdf", "url": "https://authors.library.caltech.edu/records/jf8gz-1q308/files/0004-637X_779_1_3.pdf" }, "related_objects": [ { "basename": "1309.6679v1.pdf", "url": "https://authors.library.caltech.edu/records/jf8gz-1q308/files/1309.6679v1.pdf" } ], "resource_type": "article", "pub_year": "2013", "author_list": "Line, Michael R. and Yung, Yuk L." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/zd0fb-4qm55", "eprint_id": 43869, "eprint_status": "archive", "datestamp": "2023-08-22 10:46:28", "lastmod": "2023-10-25 23:57:35", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Kammer-J-A", "name": { "family": "Kammer", "given": "J. A." }, "orcid": "0000-0002-3441-3757" }, { "id": "Shemansky-D-E", "name": { "family": "Shemansky", "given": "D. E." }, "orcid": "0000-0001-7168-871X" }, { "id": "Zhang-Xi", "name": { "family": "Zhang", "given": "X." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Y. L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Composition of Titan's upper atmosphere from Cassini UVIS EUV stellar occultations", "ispublished": "pub", "full_text_status": "restricted", "keywords": "Titan; Stellar occultation; Atmospheric composition; Data analysis", "note": "\u00a9 2013 Elsevier Ltd. \n\nReceived 1 December 2012; Received in revised form 10 July 2013; Accepted 5 August 2013; Available online 16 August 2013.\n\nThis research was supported in part by the Cassini UVIS program via NASA Grant JPL.1459109 to the California Institute of Technology. YLY and XZ were supported in part by NASA Grant NNX09AB72G to the California Institute of Technology. DES was supported through Space Environment Technologies. JAK would like to thank Michael Line for many productive discussions concerning data analysis and retrieval methodology, as well as Joseph Westlake for assistance in providing INMS derived nitrogen and methane atmospheric profiles.", "abstract": "Identifying seasonal and spatial variability in Titan's atmospheric structure is a key factor in improving theoretical models of atmospheric loss and understanding the physical processes that control the loss rate. In this work, the extreme ultraviolet (EUV) stellar occultation lightcurves from the Cassini Ultraviolet Imaging Spectrograph (UVIS) experiment are analyzed. N_2 and CH_4 atmospheric profiles between 1000 and 1400 km are determined by using an optimized grid search retrieval method to provide a complete \u03c7^2 surface for the two species abundance parameters at each level in the atmosphere. Kinetic temperature is extracted from hydrostatic analysis of the N_2 profiles, and indicates a high level of variability related to energy deposition in the upper atmosphere. These results are compared to in situ measurements by the Ion Neutral Mass Spectrometer (INMS), which also probes this region of Titan's atmosphere.", "date": "2013-11", "date_type": "published", "publication": "Planetary and Space Science", "volume": "88", "publisher": "Elsevier", "pagerange": "86-92", "id_number": "CaltechAUTHORS:20140219-095532767", "issn": "0032-0633", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140219-095532767", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "JPL.1459109" }, { "agency": "NASA", "grant_number": "NNX09AB72G" }, { "agency": "Space Environment Technologies" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/j.pss.2013.08.003", "resource_type": "article", "pub_year": "2013", "author_list": "Kammer, J. A.; Shemansky, D. E.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/f17vs-6ah96", "eprint_id": 43890, "eprint_status": "archive", "datestamp": "2023-08-22 10:46:46", "lastmod": "2023-10-25 23:58:58", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Zhang-Xi", "name": { "family": "Zhang", "given": "X." } }, { "id": "Nixon-C-A", "name": { "family": "Nixon", "given": "C. A." } }, { "id": "Shia-Run-Lie", "name": { "family": "Shia", "given": "R. L." }, "orcid": "0000-0003-1911-3120" }, { "id": "West-R-A", "name": { "family": "West", "given": "R. A." }, "orcid": "0000-0002-4320-2599" }, { "id": "Irwin-P-G-J", "name": { "family": "Irwin", "given": "P. G. J." } }, { "id": "Yelle-R-V", "name": { "family": "Yelle", "given": "R. V." } }, { "id": "Allen-M-A", "name": { "family": "Allen", "given": "M. A." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Y. L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Radiative forcing of the stratosphere of Jupiter, Part I: Atmospheric cooling rates from Voyager to Cassini", "ispublished": "pub", "full_text_status": "public", "keywords": "Jupiter atmosphere; Outer planets; Abundance retrieval; Radiative transfer; Energy balance", "note": "\u00a9 2013 Elsevier Ltd.\n\nReceived 1 December 2012; Received in revised form;\n22 May 2013; Accepted 10 July 2013; Available online 26 July 2013.\n\nWe thank V. Meadows for the latest CH_4 absorption data, G. Orton for the updated hydrogen-brodened C_(2)H_2 and C_(2)H6 line list, T. Greathouse, T. Dowling, L. Brown, R. Morales-Juberias, and M. Line for discussions and two anonymous refrees for helpful reviews. This research was supported by the Outer Planets Research program via NASA grant JPL.1452240 to the California Institute of Technology. CAN was supported in part by NASA Cassini Mission. RLS and YLY were supported in part by NASANNX09AB72G grant to the California Institute of Technology. PGJI was supported in part by the United Kingdom Science and Technology Facilities Council. The digital data files of the retrieved temperatures, gas abundances, and cooling rates are available in the online supplementary materials.\n\nSupplemental Material - mmc1.txt
Supplemental Material - mmc2.txt
Supplemental Material - mmc3.txt
Supplemental Material - mmc4.txt
Supplemental Material - mmc5.txt
Supplemental Material - mmc6.txt
Supplemental Material - mmc7.txt
Supplemental Material - mmc8.txt
Supplemental Material - mmc9.txt
", "abstract": "We developed a line-by-line heating and cooling rate model for the stratosphere of Jupiter, based on two complete sets of global maps of temperature, C_(2)H_2 and C_(2)H_6, retrieved from the Cassini and Voyager observations in the latitude and vertical plane, with a careful error analysis. The non-LTE effect is found unimportant on the thermal cooling rate below the 0.01 mbar pressure level. The most important coolants are molecular hydrogen between 10 and 100 mbar, and hydrocarbons, including ethane (C_(2)H_6), acetylene (C_(2)H_2) and methane (CH_4), in the region above. The two-dimensional cooling rate maps are influenced primarily by the temperature structure, and also by the meridional distributions of C_(2)H_2 and C_(2)H_6. The temperature anomalies at the 1 mbar pressure level in the Cassini data and the strong C_(2)H_6 latitudinal contrast in the Voyager epoch are the two most prominent features influencing the cooling rate patterns, with the effect from the 'quasi-quadrennial oscillation (QQO)' thermal structures at ~20 mbar. The globally averaged CH4 heating and cooling rates are not balanced, clearly in the lower stratosphere under 10 mbar, and possibly in the upper stratosphere above the 1 mbar pressure level. Possible heating sources from the gravity wave breaking and aerosols are discussed. The radiative relaxation timescale in the lower stratosphere implies that the temperature profile might not be purely radiatively controlled.", "date": "2013-11", "date_type": "published", "publication": "Planetary and Space Science", "volume": "88", "publisher": "Elsevier", "pagerange": "3-25", "id_number": "CaltechAUTHORS:20140220-100531697", "issn": "0032-0633", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140220-100531697", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA Outer Planets Research program", "grant_number": "JPL.1452240" }, { "agency": "NASA Cassini Mission" }, { "agency": "NASA", "grant_number": "NNX09AB72G" }, { "agency": "Science and Technology Facilities Council (STFC)" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/j.pss.2013.07.005", "primary_object": { "basename": "mmc7.txt", "url": "https://authors.library.caltech.edu/records/f17vs-6ah96/files/mmc7.txt" }, "related_objects": [ { "basename": "mmc8.txt", "url": "https://authors.library.caltech.edu/records/f17vs-6ah96/files/mmc8.txt" }, { "basename": "mmc9.txt", "url": "https://authors.library.caltech.edu/records/f17vs-6ah96/files/mmc9.txt" }, { "basename": "mmc1.txt", "url": "https://authors.library.caltech.edu/records/f17vs-6ah96/files/mmc1.txt" }, { "basename": "mmc3.txt", "url": "https://authors.library.caltech.edu/records/f17vs-6ah96/files/mmc3.txt" }, { "basename": "mmc4.txt", "url": "https://authors.library.caltech.edu/records/f17vs-6ah96/files/mmc4.txt" }, { "basename": "mmc5.txt", "url": "https://authors.library.caltech.edu/records/f17vs-6ah96/files/mmc5.txt" }, { "basename": "mmc6.txt", "url": "https://authors.library.caltech.edu/records/f17vs-6ah96/files/mmc6.txt" }, { "basename": "mmc2.txt", "url": "https://authors.library.caltech.edu/records/f17vs-6ah96/files/mmc2.txt" } ], "resource_type": "article", "pub_year": "2013", "author_list": "Zhang, X.; Nixon, C. A.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/dje8w-s8g84", "eprint_id": 42063, "eprint_status": "archive", "datestamp": "2023-08-22 10:32:48", "lastmod": "2024-02-02 21:11:32", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Line-M-R", "name": { "family": "Line", "given": "Michael R." }, "orcid": "0000-0002-2338-476X" }, { "id": "Wolf-A-S", "name": { "family": "Wolf", "given": "Aaron S." } }, { "id": "Zhang-Xi", "name": { "family": "Zhang", "given": "Xi" } }, { "id": "Knutson-H-A", "name": { "family": "Knutson", "given": "Heather" }, "orcid": "0000-0002-5375-4725" }, { "id": "Kammer-J-A", "name": { "family": "Kammer", "given": "Joshua A." }, "orcid": "0000-0002-3441-3757" }, { "id": "Ellison-E", "name": { "family": "Ellison", "given": "Elias" } }, { "id": "Deroo-P", "name": { "family": "Deroo", "given": "Pieter" } }, { "id": "Crisp-D", "name": { "family": "Crisp", "given": "Dave" }, "orcid": "0000-0002-4573-9998" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "A Systematic Retrieval Analysis of Secondary Eclipse Spectra. I. A Comparison of Atmospheric Retrieval Techniques", "ispublished": "pub", "full_text_status": "public", "keywords": "methods: data analysis; methods: statistical; planets and satellites: atmospheres; radiative transfer", "note": "\u00a9 2013 American Astronomical Society.\n\nReceived 2013 April 19; accepted 2013 August 19; published 2013 September 16.\n\nWe thank Jaimin Lee and Leigh Fletcher for their willingness\nto compare radiative transfer codes. We also thank John Johnson\nand Jonathan Fortney for useful conversations. We thank members\nof Yuk Yungs group for useful comments. This research\nwas supported in part by an NAI Virtual Planetary Laboratory\ngrant from the University of Washington to the Jet Propulsion\nLaboratory and California Institute of Technology. Part of the\nresearch described here was carried out at the Jet Propulsion\nLaboratory, California Institute of Technology, under a contract\nwith the National Aeronautics and Space Administration.\nY.L.Y. was supported in part by NASA grant NNX09AB72G to\nthe California Institute of Technology.\n\nPublished - 0004-637X_775_2_137.pdf
Submitted - 1304.5561v2.pdf
", "abstract": "Exoplanet atmosphere spectroscopy enables us to improve our understanding of exoplanets just as remote sensing in our own solar system has increased our understanding of the solar system bodies. The challenge is to quantitatively determine the range of temperatures and molecular abundances allowed by the data, which is often difficult given the low information content of most exoplanet spectra that commonly leads to degeneracies in the interpretation. A variety of spectral retrieval approaches have been applied to exoplanet spectra, but no previous investigations have sought to compare these approaches. We compare three different retrieval methods: optimal estimation, differential evolution Markov chain Monte Carlo, and bootstrap Monte Carlo on a synthetic water-dominated hot Jupiter. We discuss expectations of uncertainties in abundances and temperatures given current and potential future observations. In general, we find that the three approaches agree for high spectral resolution, high signal-to-noise data expected to come from potential future spaceborne missions, but disagree for low-resolution, low signal-to-noise spectra representative of current observations. We also compare the results from a parameterized temperature profile versus a full classical Level-by-Level approach and discriminate in which situations each of these approaches is applicable. Furthermore, we discuss the implications of our models for the inferred C-to-O ratios of exoplanetary atmospheres. Specifically, we show that in the observational limit of a few photometric points, the retrieved C/O is biased toward values near solar and near one simply due to the assumption of uninformative priors.", "date": "2013-10-01", "date_type": "published", "publication": "Astrophysical Journal", "volume": "775", "number": "2", "publisher": "American Astronomical Society", "pagerange": "Art. No. 137", "id_number": "CaltechAUTHORS:20131025-101347975", "issn": "0004-637X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20131025-101347975", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "University of Washington NAI Virtual Planetary Laboratory" }, { "agency": "NASA", "grant_number": "NNX09AB72G" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1088/0004-637X/775/2/137", "primary_object": { "basename": "0004-637X_775_2_137.pdf", "url": "https://authors.library.caltech.edu/records/dje8w-s8g84/files/0004-637X_775_2_137.pdf" }, "related_objects": [ { "basename": "1304.5561v2.pdf", "url": "https://authors.library.caltech.edu/records/dje8w-s8g84/files/1304.5561v2.pdf" } ], "resource_type": "article", "pub_year": "2013", "author_list": "Line, Michael R.; Wolf, Aaron S.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/b7hbm-k2b68", "eprint_id": 42258, "eprint_status": "archive", "datestamp": "2023-08-19 21:37:37", "lastmod": "2023-10-25 15:47:24", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Liang-Mao-Chang", "name": { "family": "Liang", "given": "Mao-Chang" }, "orcid": "0000-0002-5294-9344" }, { "id": "Lin-Li-Ching", "name": { "family": "Lin", "given": "Li-Ching" } }, { "id": "Tung-Ka-Kit", "name": { "family": "Tung", "given": "Ka-Kit" }, "orcid": "0000-0001-8667-7167" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Sun-Shan", "name": { "family": "Sun", "given": "Shan" } } ] }, "title": "Impact of Climate Drift on Twenty-First-Century Projection in a Coupled Atmospheric\u2013Ocean General Circulation Model", "ispublished": "pub", "full_text_status": "public", "keywords": "Climate models, Coupled models, Model comparison, Model evaluation/performance, Climate variability, Trends", "note": "\u00a9 2013 American Meteorological Society. Manuscript received 9 May 2013, in final form 25 June 2013. We thank editor Ming Cai for his detailed suggestions and two anonymous reviewers for their comments that helped focus the presentation. This\nwork is supported in part by NSC Grant 101-2628-M-001-001-MY4 to Academia Sinica and its Grid Computing\nCenter, KKT's research by NSF Grants ATM 0808375 and DMS 0940342, and YLY's by Caltech's KISS program.\n\nPublished - jas-d-13-0149.1.pdf
", "abstract": "Reducing climate drift in coupled atmosphere\u2013ocean general circulation models (AOGCMs) usually requires 1000\u20132000 years of spinup, which has not been practical for every modeling group to do. For the purpose of evaluating the impact of climate drift, the authors have performed a multimillennium-long control run of the Goddard Institute for Space Studies model (GISS-EH) AOGCM and produced different twentieth-century historical simulations and subsequent twenty-first-century projections by branching off the control run at various stages of equilibration. The control run for this model is considered at quasi equilibration after a 1200-yr spinup from a cold start. The simulations that branched off different points after 1200 years are robust, in the sense that their ensemble means all produce the same future projection of warming, both in the global mean and in spatial detail. These robust projections differ from the one that was originally submitted to the Intergovernmental Panel on Climate Change (IPCC) Fourth Assessment Report (AR4), which branched off a not-yet-equilibrated control run. The authors test various common postprocessing schemes in removing climate drift caused by a not-yet-equilibrated ocean initial state and find them to be ineffective, judging by the fact that they differ from each other and from the robust results that branched off an equilibrated control. The authors' results suggest that robust twenty-first-century projections of the forced response can be achieved by running climate simulations from an equilibrated ocean state, because memory of the different initial ocean state is lost in about 40 years if the forced run is started from a quasi-equilibrated state.", "date": "2013-10", "date_type": "published", "publication": "Journal of the Atmospheric Sciences", "volume": "70", "number": "10", "publisher": "American Meteorological Society", "pagerange": "3321-3327", "id_number": "CaltechAUTHORS:20131105-152313847", "issn": "0022-4928", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20131105-152313847", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "National Science Council (Taipei)", "grant_number": "101-2628-M-001-001-MY4" }, { "agency": "NSF", "grant_number": "ATM-0808375" }, { "agency": "NSF", "grant_number": "DMS-0940342" }, { "agency": "Keck Institute for Space Studies (KISS)" } ] }, "local_group": { "items": [ { "id": "Keck-Institute-for-Space-Studies" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1175/JAS-D-13-0149.1", "primary_object": { "basename": "jas-d-13-0149.1.pdf", "url": "https://authors.library.caltech.edu/records/b7hbm-k2b68/files/jas-d-13-0149.1.pdf" }, "resource_type": "article", "pub_year": "2013", "author_list": "Liang, Mao-Chang; Lin, Li-Ching; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/r471q-sgd15", "eprint_id": 48819, "eprint_status": "archive", "datestamp": "2023-08-22 10:15:17", "lastmod": "2023-10-17 20:27:24", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Shi-Yuan", "name": { "family": "Shi", "given": "Yuan" } }, { "id": "Li-King-Fai", "name": { "family": "Li", "given": "King-Fai" }, "orcid": "0000-0003-0150-2910" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Aumann-H-H", "name": { "family": "Aumann", "given": "Hartmut H." }, "orcid": "0000-0002-4311-7546" }, { "id": "Shi-Zuoqiang", "name": { "family": "Shi", "given": "Zuoqiang" } }, { "id": "Hou-T-Y", "name": { "family": "Hou", "given": "Thomas Y." } } ] }, "title": "A decadal microwave record of tropical air temperature from AMSU-A/aqua observations", "ispublished": "pub", "full_text_status": "restricted", "keywords": "Atmospheric variability; Principal mode decomposition; Adaptive analysis; Amplitude and phase profiles; Near-annual variability; Temperature trends", "note": "\u00a9 2013 Springer-Verlag Berlin Heidelberg.\n\nReceived: 6 June 2012; Accepted: 4 February 2013; Published online: 27 February 2013.\n\nWe thank Dr. Dong L. Wu for critical comments and two anonymous referees for constructive criticisms that\nimproved this paper. YS was supported by Overseas Research Fellowship of the Faculty of Science and Department of Physics, The University of Hong Kong. The extraction of the AMSU-A/Aqua data from the Atmospheric InfraRed Spectrometer (AIRS)/AMSU-A data archive was supported by a research grant administered by Dr. Ramesh Kakar, EOS Aqua Programme Scientist at NASA Headquarter and the Keck Institute for Space Studies at California Institute of Technology. We also thank Dr. Thomas Hearty for proofreading our paper and sharing his results on AIRS data. The TMI SST data were\ndownloaded from ftp://ssmi.com/tmi/. The standardized zonal winds at 30 and 50 hPa (u30hPa and u50hPa) were downloaded from http://www.cpc.ncep.noaa.gov/data/indices/. The MEI index for ENSO was downloaded from http://www.esrl.noaa.gov/psd/enso/mei/. YLY designed the approach; HHA provided the monthly-averaged AMSU-A/Aqua data; TYH and ZS provided the DMP package; ZS and YS developed the EJME package; YS performed the time series decomposition; KFL, YLY, and YS interpreted the results and wrote most of the manuscript.", "abstract": "Atmospheric temperature is one of the most important climate variables. This observational study presents detailed descriptions of the temperature variability imprinted in the 9-year brightness temperature data acquired by the Advanced Microwave Sounding Unit-Instrument A (AMSU-A) aboard Aqua since September 2002 over tropical oceans. A non-linear, adaptive method called the Ensemble Joint Multiple Extraction has been employed to extract the principal modes of variability in the AMSU-A/Aqua data. The semi-annual, annual, quasi-biennial oscillation (QBO) modes and QBO\u2013annual beat in the troposphere and the stratosphere have been successfully recovered. The modulation by the El Ni\u00f1o/Southern oscillation (ENSO) in the troposphere was found and correlates well with the Multivariate ENSO Index. The long-term variations during 2002\u20132011 reveal a cooling trend (\u22120.5 K/decade at 10 hPa) in the tropical stratosphere; the trend below the tropical tropopause is not statistically significant due to the length of our data. A new tropospheric near-annual mode (period ~1.6 years) was also revealed in the troposphere, whose existence was confirmed using National Centers for Environmental Prediction Reanalysis air temperature data. The near-annual mode in the troposphere is found to prevail in the eastern Pacific region and is coherent with a near-annual mode in the observed sea surface temperature over the Warm Pool region that has previously been reported. It remains a challenge for climate models to simulate the trends and principal modes of natural variability reported in this work.", "date": "2013-09", "date_type": "published", "publication": "Climate Dynamics", "volume": "41", "number": "5-6", "publisher": "Springer", "pagerange": "1385-1405", "id_number": "CaltechAUTHORS:20140822-131136037", "issn": "0930-7575", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140822-131136037", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "University of Hong Kong" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1007/s00382-013-1696-x", "resource_type": "article", "pub_year": "2013", "author_list": "Shi, Yuan; Li, King-Fai; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/7htrj-d9m95", "eprint_id": 42200, "eprint_status": "archive", "datestamp": "2023-08-22 10:14:07", "lastmod": "2023-10-23 16:58:22", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Zhang-X", "name": { "family": "Zhang", "given": "X." } }, { "id": "West-R-A", "name": { "family": "West", "given": "R. A." }, "orcid": "0000-0002-4320-2599" }, { "id": "Banfield-D", "name": { "family": "Banfield", "given": "D." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Y. L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Stratospheric aerosols on Jupiter from Cassini observations", "ispublished": "pub", "full_text_status": "restricted", "keywords": "Jupiter, Atmosphere; Photometry; Radiative transfer; Atmospheres, Structure", "note": "\u00a9 2013 Elsevier Inc. \n\nReceived 27 February 2013. Revised 10 April 2013. Accepted 21 May 2013. Available online 5 June 2013. \n\nWe thank M. Lemmon for the parameterization model for the aggregated particles, T. Dowling for the C-DISORT program, P.G. Irwin for the CH_4 correlated-k coefficients, M. Line for helpful discussions, and K. Rages and the other reviewer for useful comments. This research was supported by the Outer Planets Research program via NASA Grant JPL 1452240 to the California Institute of Technology. Y.L.Y. was supported in part by NASA NNX09AB72G grant to the California Institute of Technology. X.Z. was supported in part by the Bisgrove Scholar Program in the University of Arizona.", "abstract": "We retrieved global distributions and optical properties of stratospheric aerosols on Jupiter from ground-based NIR spectra and multiple-phase-angle images from Cassini Imaging Science Subsystem (ISS). A high-latitude haze layer is located at \u223c10\u201320 mbar, higher than in the middle and low latitudes (\u223c50 mbar). Compact sub-micron particles are mainly located in the low latitudes between 40\u00b0S and 25\u00b0N with the particle radius between 0.2 and 0.5 \u03bcm. The rest of the stratosphere is covered by the particles known as fractal aggregates. In the nominal case with the imaginary part of the UV refractive index 0.02, the fractal aggregates are composed of about a thousand 10-nm-size monomers. The column density of the aerosols at pressure less than 100 mbar ranges from \u223c10^7 cm^(\u22122) at low latitudes to \u223c10^9 cm^(\u22122) at high latitudes. The mass loading of aerosols in the stratosphere is \u223c10^(\u22126) g cm^(\u22122) at low latitudes to \u223c10^(\u22124) g cm^(\u22122) in the high latitudes. Multiple solutions due to the uncertainty of the imaginary part of the refractive index are discussed. The stratospheric haze optical depths increase from \u223c0.03 at low latitudes to about a few at high latitudes in the UV wavelength (\u223c0.26 \u03bcm), and from \u223c0.03 at low latitudes to \u223c0.1 at high latitudes in the NIR wavelength (\u223c0.9 \u03bcm).", "date": "2013-09", "date_type": "published", "publication": "Icarus", "volume": "221", "number": "1", "publisher": "Elsevier", "pagerange": "159-171", "id_number": "CaltechAUTHORS:20131101-143614601", "issn": "0019-1035", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20131101-143614601", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "JPL 452240" }, { "agency": "NASA", "grant_number": "NNX09AB72G" }, { "agency": "University of Arizona" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/j.icarus.2013.05.020", "resource_type": "article", "pub_year": "2013", "author_list": "Zhang, X.; West, R. A.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/rrkay-vkz82", "eprint_id": 48817, "eprint_status": "archive", "datestamp": "2023-08-22 10:02:59", "lastmod": "2023-10-17 20:27:17", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Jiang-Xun", "name": { "family": "Jiang", "given": "Xun" }, "orcid": "0000-0001-8932-3807" }, { "id": "Wang-Jingqian", "name": { "family": "Wang", "given": "Jingqian" } }, { "id": "Olsen-E-T", "name": { "family": "Olsen", "given": "Edward T." } }, { "id": "Pagano-T-S", "name": { "family": "Pagano", "given": "Thomas" } }, { "id": "Chen-Luke-L", "name": { "family": "Chen", "given": "Luke L." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Influence of Stratospheric Sudden Warming on AIRS Midtropospheric CO_2", "ispublished": "pub", "full_text_status": "public", "keywords": "Stratospheric circulation; Air pollution", "note": "\u00a9 2013 American Meteorological Society.\n\nManuscript received and in final form 15 February 2013.\n\nWe thank M. Chahine, Q. Li, two anonymous reviewers, and the editor for helpful comments. X. Jiang was supported by JPL Grant G99694. YLY was supported by the OCO-2 project. Part of the research was carried out at the Jet Propulsion\nLaboratory, California Institute of Technology, under\na contract with the National Aeronautics and Space\nAdministration.\n\nPublished - jas-d-13-064.1.pdf
", "abstract": "Midtropospheric CO_2 retrievals from the Atmospheric Infrared Sounder (AIRS) were used to explore the influence of stratospheric sudden warming (SSW) on CO_2 in the middle to upper troposphere. To choose the SSW events that had strong coupling between the stratosphere and troposphere, the authors applied a principal component analysis to the NCEP/Department of Energy Global Reanalysis 2 (NCEP-2) geopotential height data at 17 pressure levels. Two events (April 2003 and March 2005) that have strong couplings between the stratosphere and troposphere were chosen to investigate the influence of SSW on AIRS midtropospheric CO_2. The authors investigated the temporal and spatial variations of AIRS midtropospheric CO_2 before and after the SSW events and found that the midtropospheric CO_2 concentrations increased by 2\u20133 ppm within a few days after the SSW events. These results can be used to better understand how the chemical tracers respond to the large-scale dynamics in the high latitudes.", "date": "2013-08", "date_type": "published", "publication": "Journal of the Atmospheric Sciences", "volume": "70", "number": "8", "publisher": "American Meteorological Society", "pagerange": "2566-2573", "id_number": "CaltechAUTHORS:20140822-124837426", "issn": "0022-4928", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140822-124837426", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "JPL", "grant_number": "G99694" }, { "agency": "OCO-2 Project" }, { "agency": "NASA/JPL/Caltech" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1175/JAS-D-13-064.1", "primary_object": { "basename": "jas-d-13-064.1.pdf", "url": "https://authors.library.caltech.edu/records/rrkay-vkz82/files/jas-d-13-064.1.pdf" }, "resource_type": "article", "pub_year": "2013", "author_list": "Jiang, Xun; Wang, Jingqian; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/nf53h-p9c04", "eprint_id": 48813, "eprint_status": "archive", "datestamp": "2023-08-22 09:25:14", "lastmod": "2023-10-17 20:27:08", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Li-King-Fai", "name": { "family": "Li", "given": "King-Fai" }, "orcid": "0000-0003-0150-2910" }, { "id": "Tian-Baijun", "name": { "family": "Tian", "given": "Baijun" } }, { "id": "Tung-Ka-Kit", "name": { "family": "Tung", "given": "Ka-Kit" }, "orcid": "0000-0001-8667-7167" }, { "id": "Kuai-Le", "name": { "family": "Kuai", "given": "Le" }, "orcid": "0000-0001-6406-1150" }, { "id": "Worden-J-R", "name": { "family": "Worden", "given": "John R." }, "orcid": "0000-0003-0257-9549" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Slawski-B-L", "name": { "family": "Slawski", "given": "Benjiman L." } } ] }, "title": "A link between tropical intraseasonal variability and Arctic stratospheric ozone", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2013 American Geophysical Union. \n\nReceived 25 August 2012; revised 3 April 2013; accepted 4 April 2013; article first published online: 28 May 2013.\n\nK.F.L. is grateful to Prof. Simona Bordoni, Prof. Duane E. Waliser, and Dr. Xianan Jiang for their thoughtful comments. K.F.L. and Y.L.Y. were supported by National Aeronautics and Space Administration (NASA) grant JPL-1429248 to the California Institute of Technology. B.J. was supported by National Science Foundation (NSF) award ATM-0840755 to the University of California, Los Angeles. B.L.S. was supported by NSF grant ATM-0934303. Part of this research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with NASA. The RMM index was obtained from http://www.cawcr.gov.au/staff/mwheeler/maproom/RMM/RMM1RMM2.74toRealtime.txt.\n\nPublished - jgrd50391.pdf
", "abstract": "Previous studies using satellite measurements showed evidence that subtropical upper troposphere/lower stratosphere ozone (O_3) can be modulated by tropical intraseasonal variability, the most dominant form of which is the Madden Julian Oscillation (MJO) with a period of 30\u201360\u2009days. Here we further study the MJO modulation in the upper troposphere/lower stratosphere O_3 over the northern extratropics and the Arctic. Significant MJO-related O_3 signals (13\u201320 Dobson units) are found over the northern extratropics (north of 30\u00b0N). The O_3 anomalies change their magnitude and patterns depending on the phase of the MJO. Over the Arctic, the MJO-related O_3 anomalies are dominated by a wave number 2 structure and are anticorrelated with the geopotential height (GPH) anomalies at 250\u2009hPa. The latter is similar to the findings in the previous studies over subtropics and indicates that the Arctic upper troposphere/lower stratosphere O_3 anomalies are associated with dynamical motions near the tropopause. The teleconnection from the tropics to the Arctic is likely through propagation of planetary waves generated by the equatorial heating that affects the tropopause height and O_3 at high latitudes.", "date": "2013-05-27", "date_type": "published", "publication": "Journal of Geophysical Research. Atmospheres", "volume": "118", "number": "10", "publisher": "American Geophysical Union", "pagerange": "4280-4289", "id_number": "CaltechAUTHORS:20140822-113453218", "issn": "2169-897X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140822-113453218", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA/JPL", "grant_number": "1429248" }, { "agency": "NSF", "grant_number": "ATM-0840755" }, { "agency": "NSF", "grant_number": "ATM-0934303" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1002/jgrd.50391", "primary_object": { "basename": "jgrd50391.pdf", "url": "https://authors.library.caltech.edu/records/nf53h-p9c04/files/jgrd50391.pdf" }, "resource_type": "article", "pub_year": "2013", "author_list": "Li, King-Fai; Tian, Baijun; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/1eh79-7aw36", "eprint_id": 39343, "eprint_status": "archive", "datestamp": "2023-08-19 19:39:29", "lastmod": "2023-10-24 16:42:21", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Newman-S", "name": { "family": "Newman", "given": "S." }, "orcid": "0000-0003-0710-995X" }, { "id": "Jeong-Seongeun", "name": { "family": "Jeong", "given": "S." }, "orcid": "0000-0003-2032-0127" }, { "id": "Fischer-M-L", "name": { "family": "Fischer", "given": "M. L." }, "orcid": "0000-0001-7956-2361" }, { "id": "Xu-X", "name": { "family": "Xu", "given": "X." } }, { "id": "Haman-C-L", "name": { "family": "Haman", "given": "C. L." } }, { "id": "Lefer-B-L", "name": { "family": "Lefer", "given": "B." }, "orcid": "0000-0001-9520-5495" }, { "id": "Alvarez-S", "name": { "family": "Alvarez", "given": "S." } }, { "id": "Rappenglueck-B", "name": { "family": "Rappenglueck", "given": "B." } }, { "id": "Kort-E-A", "name": { "family": "Kort", "given": "E. A." }, "orcid": "0000-0003-4940-7541" }, { "id": "Andrews-A-E", "name": { "family": "Andrews", "given": "A. E." }, "orcid": "0000-0002-8552-3999" }, { "id": "Peisch-J", "name": { "family": "Peisch", "given": "J." } }, { "id": "Gurney-K-R", "name": { "family": "Gurney", "given": "K. R." }, "orcid": "0000-0001-9218-7164" }, { "id": "Miller-C-E", "name": { "family": "Miller", "given": "C. E." }, "orcid": "0000-0002-9380-4838" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Y. L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Diurnal tracking of anthropogenic CO_2 emissions in the Los Angeles basin megacity during spring 2010", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2013 Author(s). Published by Copernicus Publications on behalf of the European Geosciences Union. This work is distributed under the Creative Commons Attribution 3.0 License. \n\nReceived: 20 January 2012; Published in Atmos. Chem. Phys. Discuss.: 22 February 2012 Revised: 18 February 2013; Accepted: 29 March 2013; Published: 26 April 2013.\n\nWe appreciate productive discussions with Paul Wennberg, Debra Wunch, Michael Line, Xi Zhang, Run-Lie Shia, and Joshua Kammer. WRF winds for the timeaveraged footprints during the CalNex period were provided by Wayne Angevine of NOAA (Earth System Research Laboratory; ESRL).We thank Paul Novelli and Colm Sweeney of NOAA-ESRL for sharing their data that went into the NOAA background curtain\nproduct from which we calculated the time-varying background for CO. John S. Holloway (NOAA ESRL) provided the measurements of CO from the P3 aircraft profiles. As part of the CalNex-LA campaign, we gratefully acknowledge the support of Caltech and the California Air Resources Board in making the campaign successful. TCCON data (version GGG2012) were obtained from the TCCON Data Archive, operated by the California Institute of\nTechnology, from the website at http://tccon.ipac.caltech.edu/. SN acknowledges financial support from JPL's Director's Research and Development Fund. Analysis by MLF and SJ was supported by the\nDirector, Office of Science, of the US Department of Energy under Contract No. DE-AC02-05CH11231. We acknowledge the Keck Institute for Space Studies for financial support of publication costs and contribution by EAK.\nEdited by: M. K. Dubey\n\nPublished - acp-13-4359-2013.pdf
", "abstract": "Attributing observed CO_2 variations to human or natural cause is critical to deducing and tracking emissions from observations. We have used in situ CO_2, CO, and planetary boundary layer height (PBLH) measurements recorded during the CalNex-LA (CARB et al., 2008) ground campaign of 15 May\u201315 June 2010, in Pasadena, CA, to deduce the diurnally varying anthropogenic component of observed CO_2 in the megacity of Los Angeles (LA). This affordable and simple technique, validated by carbon isotope observations and WRF-STILT (Weather Research and Forecasting model \u2013 Stochastic Time-Inverted Lagrangian Transport model) predictions, is shown to robustly attribute observed CO_2 variation to anthropogenic or biogenic origin over the entire diurnal cycle. During CalNex-LA, local fossil fuel combustion contributed up to ~50% of the observed CO_2 enhancement overnight, and ~100% of the enhancement near midday. This suggests that sufficiently accurate total column CO_2 observations recorded near midday, such as those from the GOSAT or OCO-2 satellites, can potentially be used to track anthropogenic emissions from the LA megacity.", "date": "2013-04-26", "date_type": "published", "publication": "Atmospheric Chemistry and Physics", "volume": "13", "number": "8", "publisher": "European Geosciences Union", "pagerange": "4359-4372", "id_number": "CaltechAUTHORS:20130712-114557472", "issn": "1680-7316", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20130712-114557472", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "JPL Director's Research and Development Fund" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" }, { "agency": "Keck Institute for Space Studies (KISS)" } ] }, "local_group": { "items": [ { "id": "Keck-Institute-for-Space-Studies" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/acp-13-4359-2013", "primary_object": { "basename": "acp-13-4359-2013.pdf", "url": "https://authors.library.caltech.edu/records/1eh79-7aw36/files/acp-13-4359-2013.pdf" }, "resource_type": "article", "pub_year": "2013", "author_list": "Newman, S.; Jeong, S.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/k0608-2yf78", "eprint_id": 38571, "eprint_status": "archive", "datestamp": "2023-08-22 09:08:47", "lastmod": "2023-10-23 20:35:56", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Zhang-Xi", "name": { "family": "Zhang", "given": "Xi" } }, { "id": "Shia-Run-Lie", "name": { "family": "Shia", "given": "Run-Lie" }, "orcid": "0000-0003-1911-3120" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Jovian Stratosphere as a Chemical Transport System: Benchmark Analytical Solutions", "ispublished": "pub", "full_text_status": "public", "keywords": "astrochemistry; methods: analytical; planets and satellites: atmospheres; planets and satellites: individual (exo-planets, Jupiter)", "note": "\u00a9 2013 American Astronomical Society. Received 2013 January 2; accepted 2013 March 7; published 2013 April 8. We thank P. Gao, M. Line, M. Wong, Q. Zhang and other members of Yung's group for useful comments, and M. Gerstell for critical reading of the manuscript. This research was supported\nin part by NASA NNX09AB72G grant to the California\nInstitute of Technology.\n\nPublished - 0004-637X_767_2_172.pdf
", "abstract": "We systematically investigated the solvable analytical benchmark cases in both one- and two-dimensional (1D and 2D) chemical-advective-diffusive systems. We use the stratosphere of Jupiter as an example but the results can be applied to other planetary atmospheres and exoplanetary atmospheres. In the 1D system, we show that CH_4 and C_2H_6 are mainly in diffusive equilibrium, and the C_2H_2 profile can be approximated by modified Bessel functions. In the 2D system in the meridional plane, analytical solutions for two typical circulation patterns are derived. Simple tracer transport modeling demonstrates that the distribution of a short-lived species (such as C_2H_2) is dominated by the local chemical sources and sinks, while that of a long-lived species (such as C_2H_6) is significantly influenced by the circulation pattern. We find that an equator-to-pole circulation could qualitatively explain the Cassini observations, but a pure diffusive transport process could not. For slowly rotating planets like the close-in extrasolar planets, the interaction between the advection by the zonal wind and chemistry might cause a phase lag between the final tracer distribution and the original source distribution. The numerical simulation results from the 2D Caltech/JPL chemistry-transport model agree well with the analytical solutions for various cases.", "date": "2013-04-20", "date_type": "published", "publication": "Astrophysical Journal", "volume": "767", "number": "2", "publisher": "American Astronomical Society", "pagerange": "Art. No. 172", "id_number": "CaltechAUTHORS:20130517-145616935", "issn": "0004-637X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20130517-145616935", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NNX09AB72G" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1088/0004-637X/767/2/172", "primary_object": { "basename": "0004-637X_767_2_172.pdf", "url": "https://authors.library.caltech.edu/records/k0608-2yf78/files/0004-637X_767_2_172.pdf" }, "resource_type": "article", "pub_year": "2013", "author_list": "Zhang, Xi; Shia, Run-Lie; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/e5wg2-7kg54", "eprint_id": 38243, "eprint_status": "archive", "datestamp": "2023-08-22 08:59:51", "lastmod": "2023-10-23 19:58:05", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Liang-Mao-Chang", "name": { "family": "Liang", "given": "Mao-Chang" }, "orcid": "0000-0002-5294-9344" }, { "id": "Lin-Li-Ching", "name": { "family": "Lin", "given": "Li-Ching" } }, { "id": "Tung-Ka-Kit", "name": { "family": "Tung", "given": "Ka-Kit" }, "orcid": "0000-0001-8667-7167" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Sun-Shan", "name": { "family": "Sun", "given": "Shan" } } ] }, "title": "Transient Climate Response in Coupled Atmospheric\u2013Ocean General Circulation Models", "ispublished": "pub", "full_text_status": "public", "keywords": "Climate prediction; Climate sensitivity; Climate models", "note": "\u00a9 2013 American Meteorological Society.\n\nReceived: December 11, 2012; accepted: January 10, 2013.\n\nThe research is performed using high performance computing resources provided byASCC and ASGC. This work is supported in part by NSC Grant 101-2628-M-001-001-MY4 to Academia Sinica. KKT's research is supported by National Science Foundation,\nunder Grant DMS 0940342, and the National Aeronautics\nand Space Administration, under Grant NNX11AC75G. YLY acknowledges support from the KISS program at\nthe California Institute of Technology.\n\nPublished - jas-d-12-0338.1.pdf
", "abstract": "The equilibrium climate sensitivity (ECS) has a large uncertainty range among models participating in the Intergovernmental Panel on Climate Change (IPCC) Fourth Assessment Report (AR4) and has recently been presented as \"inherently unpredictable.\" One way to circumvent this problem is to consider the transient climate response (TCR). However, the TCR among AR4 models also differs by more than a factor of 2. The authors argue that the situation may not necessarily be so pessimistic, because much of the intermodel difference may be due to the fact that the models were run with their oceans at various stages of flux adjustment with their atmosphere. This is shown by comparing multimillennium-long runs of the Goddard Institute for Space Studies model, version E, coupled with the Hybrid Coordinate Ocean Model (GISS-EH) and the Community Climate System Model, version 4 (CCSM4) with what were reported to AR4. The long model runs here reveal the range of variability (~30%) in their TCR within the same model with the same ECS. The commonly adopted remedy of subtracting the \"climate drift\" is ineffective and adds to the variability. The culprit is the natural variability of the control runs, which exists even at quasi equilibration. Fortunately, for simulations with multidecadal time horizon, robust solutions can be obtained by branching off thousand-year-long control runs that reach \"quasi equilibration\" using a new protocol, which takes advantage of the fact that forced solutions to radiative forcing forget their initial condition after 30\u201340 yr and instead depend mostly on the trajectory of the radiative forcing.", "date": "2013-04", "date_type": "published", "publication": "Journal of the Atmospheric Sciences", "volume": "70", "number": "4", "publisher": "American Meteorological Society", "pagerange": "1291-1296", "id_number": "CaltechAUTHORS:20130502-131813872", "issn": "0022-4928", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20130502-131813872", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "National Science Council (Taipei)", "grant_number": "101-2628-M-001-001-MY4" }, { "agency": "NSF", "grant_number": "DMS-0940342" }, { "agency": "NASA", "grant_number": "NNX11AC75G" }, { "agency": "Keck Institute for Space Studies (KISS)" } ] }, "local_group": { "items": [ { "id": "Keck-Institute-for-Space-Studies" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1175/JAS-D-12-0338.1", "primary_object": { "basename": "jas-d-12-0338.1.pdf", "url": "https://authors.library.caltech.edu/records/e5wg2-7kg54/files/jas-d-12-0338.1.pdf" }, "resource_type": "article", "pub_year": "2013", "author_list": "Liang, Mao-Chang; Lin, Li-Ching; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/x5p0c-3pg52", "eprint_id": 37807, "eprint_status": "archive", "datestamp": "2023-08-22 08:40:16", "lastmod": "2023-10-23 18:04:31", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Wang-Shuhui", "name": { "family": "Wang", "given": "Shuhui" } }, { "id": "Li-King-Fai", "name": { "family": "Li", "given": "King-Fai" }, "orcid": "0000-0003-0150-2910" }, { "id": "Pongetti-T-J", "name": { "family": "Pongetti", "given": "Thomas J." }, "orcid": "0000-0001-9465-0853" }, { "id": "Sander-S-P", "name": { "family": "Sander", "given": "Stanley P." }, "orcid": "0000-0003-1424-3620" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Liang-Mao-Chang", "name": { "family": "Liang", "given": "Mao-Chang" }, "orcid": "0000-0002-5294-9344" }, { "id": "Livesey-N-J", "name": { "family": "Livesey", "given": "Nathaniel J." } }, { "id": "Santee-M-L", "name": { "family": "Santee", "given": "Michelle L." } }, { "id": "Harder-J-W", "name": { "family": "Harder", "given": "Jerald W." } }, { "id": "Snow-M", "name": { "family": "Snow", "given": "Martin" } }, { "id": "Mills-F-P", "name": { "family": "Mills", "given": "Franklin P." } } ] }, "title": "Midlatitude atmospheric OH response to the most recent 11-y solar cycle", "ispublished": "pub", "full_text_status": "public", "keywords": "decadal variability; odd hydrogen", "note": "\u00a9 2013 National Academy of Sciences.\n\nEdited by Steven C. Wofsy, Harvard University, Cambridge, MA, and approved December 19, 2012 (received for review November 1, 2011).\nPublished online before print January 22, 2013.\nWe thank the NASA Aura Science Team and the Upper Atmosphere Research and Tropospheric Chemistry programs for\ntheir support. We thank R. C. Willson for providing the ACRIM TSI composite (www.acrim.com) and the Laboratory for Atmospheric and Space Physics Interactive Solar Irradiance Datacenter for composites of Lyman-\u03b1 and Mg-II indices (http://lasp.colorado.edu/lisird/). We also acknowledge\nreceipt of a TSI dataset from the PMOD (www.pmodwrc.ch/)\nand receipt of unpublished data from the Variability of Solar Irradiance and Gravity Oscillations on board the Solar and Heliospheric Observatory. Some FTUVS OH data from early years were collected by R. P. Cageao. We thank H. M. Pickett, the principal investigator (retired) for the MLS OH measurements and a NASA Aura Science Team project. We\nalso thank R.-L. Shia and S. Newman for help with the models and error analysis and insightful discussions. Work at the Jet Propulsion Laboratory, California Institute of Technology, was done under contract to NASA. Support from an Australian Research Council Linkage International\ngrant is gratefully acknowledged.\n\nAuthor contributions: S.W., K.-F.L., S.P.S., Y.L.Y., and F.P.M. designed research; S.W., K.-F.L.,\nand T.J.P. performed research; M.-C.L., J.W.H., and M.S. contributed new reagents/analytic\ntools; S.W., T.J.P., N.J.L., M.L.S., J.W.H., and M.S. analyzed data; and S.W. and K.-F.L. wrote\nthe paper.\n\nPublished - PNAS-2013-Wang-2023-8.pdf
Supplemental Material - pnas.201117790SI.pdf
Supplemental Material - sd01.txt
", "abstract": "The hydroxyl radical (OH) plays an important role in middle atmospheric photochemistry, particularly in ozone (O_3) chemistry. Because it is mainly produced through photolysis and has a short chemical lifetime, OH is expected to show rapid responses to solar forcing [e.g., the 11-y solar cycle (SC)], resulting in variabilities in related middle atmospheric O_3 chemistry. Here, we present an effort to investigate such OH variability using long-term observations (from space and the surface) and model simulations. Ground-based measurements and data from the Microwave Limb Sounder on the National Aeronautics and Space Administration's Aura satellite suggest an \u223c7\u201310% decrease in OH column abundance from solar maximum to solar minimum that is highly correlated with changes in total solar irradiance, solar Mg-II index, and Lyman-\u03b1 index during SC 23. However, model simulations using a commonly accepted solar UV variability parameterization give much smaller OH variability (\u223c3%). Although this discrepancy could result partially from the limitations in our current understanding of middle atmospheric chemistry, recently published solar spectral irradiance data from the Solar Radiation and Climate Experiment suggest a solar UV variability that is much larger than previously believed. With a solar forcing derived from the Solar Radiation and Climate Experiment data, modeled OH variability (\u223c6\u20137%) agrees much better with observations. Model simulations reveal the detailed chemical mechanisms, suggesting that such OH variability and the corresponding catalytic chemistry may dominate the O_3 SC signal in the upper stratosphere. Continuing measurements through SC 24 are required to understand this OH variability and its impacts on O_3 further.", "date": "2013-02-05", "date_type": "published", "publication": "Proceedings of the National Academy of Sciences of the United States of America", "volume": "110", "number": "6", "publisher": "National Academy of Sciences", "pagerange": "2023-2028", "id_number": "CaltechAUTHORS:20130408-133142312", "issn": "0027-8424", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20130408-133142312", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA" }, { "agency": "Australian Research Council" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1073/pnas.1117790110", "pmcid": "PMC3568342", "primary_object": { "basename": "pnas.201117790SI.pdf", "url": "https://authors.library.caltech.edu/records/x5p0c-3pg52/files/pnas.201117790SI.pdf" }, "related_objects": [ { "basename": "sd01.txt", "url": "https://authors.library.caltech.edu/records/x5p0c-3pg52/files/sd01.txt" }, { "basename": "PNAS-2013-Wang-2023-8.pdf", "url": "https://authors.library.caltech.edu/records/x5p0c-3pg52/files/PNAS-2013-Wang-2023-8.pdf" } ], "resource_type": "article", "pub_year": "2013", "author_list": "Wang, Shuhui; Li, King-Fai; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/gvc7c-33780", "eprint_id": 37845, "eprint_status": "archive", "datestamp": "2023-08-22 08:18:33", "lastmod": "2023-10-23 19:02:57", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Kuai-Le", "name": { "family": "Kuai", "given": "L." }, "orcid": "0000-0001-6406-1150" }, { "id": "Worden-J", "name": { "family": "Worden", "given": "J." } }, { "id": "Kulawik-S-S", "name": { "family": "Kulawik", "given": "S." } }, { "id": "Bowman-K-W", "name": { "family": "Bowman", "given": "K." }, "orcid": "0000-0002-8659-1117" }, { "id": "Lee-M", "name": { "family": "Lee", "given": "M." } }, { "id": "Biraud-S-C", "name": { "family": "Biraud", "given": "S. C." } }, { "id": "Abshire-J-B", "name": { "family": "Abshire", "given": "J. B." } }, { "id": "Wofsy-S-C", "name": { "family": "Wofsy", "given": "S. C." }, "orcid": "0000-0002-3990-6737" }, { "id": "Natraj-V", "name": { "family": "Natraj", "given": "V." }, "orcid": "0000-0003-3154-9429" }, { "id": "Frankenberg-C", "name": { "family": "Frankenberg", "given": "C." }, "orcid": "0000-0002-0546-5857" }, { "id": "Wunch-D", "name": { "family": "Wunch", "given": "D." }, "orcid": "0000-0002-4924-0377" }, { "id": "Connor-B", "name": { "family": "Connor", "given": "B." } }, { "id": "Miller-C-E", "name": { "family": "Miller", "given": "C." }, "orcid": "0000-0002-9380-4838" }, { "id": "Roehl-C-M", "name": { "family": "Roehl", "given": "C." }, "orcid": "0000-0001-5383-8462" }, { "id": "Shia-Run-Lie", "name": { "family": "Shia", "given": "R.-L." }, "orcid": "0000-0003-1911-3120" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Y." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Profiling tropospheric CO_2 using Aura TES and TCCON instruments", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2013 Author(s). Published by Copernicus Publications on behalf of the European Geosciences Union. This work is distributed under the Creative Commons Attribution 3.0 License. \n\nReceived: 30 May 2012. Published in Atmos. Meas. Tech. Discuss.: 29 June 2012. Revised: 22 November 2012. Accepted: 7 December 2012. Published: 10 January 2013. \n\nPart of this research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration. The GEOS-Chem model results with assimilated TES data was funded by proposal No. 09-ACOS09-0010. US funding for TCCON comes from NASA's Terrestrial Ecology Program, grant number NNX11AG01G, the Orbiting Carbon Observatory Program, the Atmospheric CO2 Observations from Space (ACOS) Program and the DOE/ARM Program. SGP data was supported by the Office of Biological and Environmental Research of the US Department of Energy under contract No. DE-AC02-05CH11231 as part of the Atmospheric Radiation Measurement Program. The authors wish to thank G. Toon and P. Wennberg for making available their GFIT code and TCCON data. \n\nEdited by: K. Strong\n\nPublished - amt-6-63-2013.pdf
", "abstract": "Monitoring the global distribution and long-term variations of CO_2 sources and sinks is required for characterizing the global carbon budget. Total column measurements are useful for estimating regional-scale fluxes; however, model transport remains a significant error source, particularly for quantifying local sources and sinks. To improve the capability of estimating regional fluxes, we estimate lower tropospheric CO_2 concentrations from ground-based near-infrared (NIR) measurements with space-based thermal infrared (TIR) measurements. The NIR measurements are obtained from the Total Carbon Column Observing Network (TCCON) of solar measurements, which provide an estimate of the total CO_2 column amount. Estimates of tropospheric CO_2 that are co-located with TCCON are obtained by assimilating Tropospheric Emission Spectrometer (TES) free tropospheric CO_2 estimates into the GEOS-Chem model. We find that quantifying lower tropospheric CO_2 by subtracting free tropospheric CO_2 estimates from total column estimates is a linear problem, because the calculated random uncertainties in total column and lower tropospheric estimates are consistent with actual uncertainties as compared to aircraft data. For the total column estimates, the random uncertainty is about 0.55 ppm with a bias of \u22125.66 ppm, consistent with previously published results. After accounting for the total column bias, the bias in the lower tropospheric CO_2 estimates is 0.26 ppm with a precision (one standard deviation) of 1.02 ppm. This precision is sufficient for capturing the winter to summer variability of approximately 12 ppm in the lower troposphere; double the variability of the total column. This work shows that a combination of NIR and TIR measurements can profile CO_2 with the precision and accuracy needed to quantify lower tropospheric CO_2 variability.", "date": "2013-01-10", "date_type": "published", "publication": "Atmospheric Measurement Techniques", "volume": "6", "number": "1", "publisher": "European Geosciences Union", "pagerange": "63-79", "id_number": "CaltechAUTHORS:20130410-084448835", "issn": "1867-1381", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20130410-084448835", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA/JPL/Caltech" }, { "agency": "NASA", "grant_number": "09-ACOS09-0010" }, { "agency": "NASA", "grant_number": "NNX11AG01G" }, { "agency": "Orbiting Carbon Observatory Program" }, { "agency": "Atmospheric CO2 Observations Space (ACOS) Program" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/amt-6-63-2013", "primary_object": { "basename": "amt-6-63-2013.pdf", "url": "https://authors.library.caltech.edu/records/gvc7c-33780/files/amt-6-63-2013.pdf" }, "resource_type": "article", "pub_year": "2013", "author_list": "Kuai, L.; Worden, J.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/pzm7h-kc548", "eprint_id": 48814, "eprint_status": "archive", "datestamp": "2023-08-22 08:08:22", "lastmod": "2023-10-17 20:27:10", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Jiang-Xun", "name": { "family": "Jiang", "given": "Xun" }, "orcid": "0000-0001-8932-3807" }, { "id": "Wang-Jingqian", "name": { "family": "Wang", "given": "Jingqian" } }, { "id": "Olsen-E-T", "name": { "family": "Olsen", "given": "Edward T." } }, { "id": "Liang-Mao-Chang", "name": { "family": "Liang", "given": "MaoChang" }, "orcid": "0000-0002-5294-9344" }, { "id": "Pagano-T-S", "name": { "family": "Pagano", "given": "Thomas S." } }, { "id": "Chen-Luke-L", "name": { "family": "Chen", "given": "Luke L." } }, { "id": "Licata-S-J", "name": { "family": "Licata", "given": "Stephen J." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Influence of El Ni\u00f1o on Midtropospheric CO_2 from Atmospheric Infrared Sounder and Model", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2013 American Meteorological Society. \n\nManuscript received 19 October 2011, in final form 13 January 2012. \n\nWe especially acknowledge Moustafa Chahine, Alexander Ruzmaikin, and Mimi Gerstell, who gave helpful suggestions on this research. XJ was supported by JPL Grant G99694. YLY was supported by the JPL OCO-2 project. Part of this research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration.\n\nPublished - jas-d-11-0282_2E1.pdf
", "abstract": "The authors investigate the influence of El Ni\u00f1o on midtropospheric CO_2 from the Atmospheric Infrared Sounder (AIRS) and the Model for Ozone and Related Chemical Tracers, version 2 (MOZART-2). AIRS midtropospheric CO_2 data are used to study the temporal and spatial variability of CO_2 in response to El Ni\u00f1o. CO_2 differences between the central and western Pacific Ocean correlate well with the Southern Oscillation index. To reveal the temporal and spatial variability of the El Ni\u00f1o signal in the AIRS midtropospheric CO_2, a multiple regression method is applied to the CO_2 data from September 2002 to February 2011. There is more (less) midtropospheric CO_2 in the central Pacific and less (more) midtropospheric CO_2 in the western Pacific during El Ni\u00f1o (La Ni\u00f1a) events. Similar results are seen in the MOZART-2 convolved midtropospheric CO_2, although the El Ni\u00f1o signal in the MOZART-2 is weaker than that in the AIRS data.", "date": "2013-01", "date_type": "published", "publication": "Journal of the Atmospheric Sciences", "volume": "70", "number": "1", "publisher": "American Meteorological Society", "pagerange": "223-230", "id_number": "CaltechAUTHORS:20140822-120706494", "issn": "0022-4928", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140822-120706494", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "JPL", "grant_number": "G99694" }, { "agency": "JPL OCO-2 Project" }, { "agency": "NASA/JPL/Caltech" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1175/JAS-D-11-0282.1", "primary_object": { "basename": "jas-d-11-0282_2E1.pdf", "url": "https://authors.library.caltech.edu/records/pzm7h-kc548/files/jas-d-11-0282_2E1.pdf" }, "resource_type": "article", "pub_year": "2013", "author_list": "Jiang, Xun; Wang, Jingqian; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/1ymwr-xrg44", "eprint_id": 52937, "eprint_status": "archive", "datestamp": "2023-08-22 07:05:22", "lastmod": "2023-10-18 21:47:35", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Tinetti-G", "name": { "family": "Tinetti", "given": "G." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Y." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "EChO", "ispublished": "pub", "full_text_status": "restricted", "keywords": "Exoplanets; Planetary atmospheres; Space mission", "note": "\u00a9 2012 Springer Science+Business Media B.V.\n\nReceived: 30 April 2011; Accepted: 9 May 2012; Published online: 2 August 2012.\n\nWe thank F. Henry, S. Cnudde, CNES/PASO, Astrium GmbH Germany,\nAIM Infrarot-Module GmbH and Astrium UK for their support in preparing the EChO proposal.", "abstract": "A dedicated mission to investigate exoplanetary atmospheres represents a major milestone in our quest to understand our place in the universe by placing our Solar System in context and by addressing the suitability of planets for the presence of life. EChO\u2014the Exoplanet Characterisation Observatory\u2014is a mission concept specifically geared for this purpose. EChO will provide simultaneous, multi-wavelength spectroscopic observations on a stable platform that will allow very long exposures. The use of passive cooling, few moving parts and well established technology gives a low-risk and potentially long-lived mission. EChO will build on observations by Hubble, Spitzer and ground-based telescopes, which discovered the first molecules and atoms in exoplanetary atmospheres. However, EChO's configuration and specifications are designed to study a number of systems in a consistent manner that will eliminate the ambiguities affecting prior observations. EChO will simultaneously observe a broad enough spectral region\u2014from the visible to the mid-infrared\u2014to constrain from one single spectrum the temperature structure of the atmosphere, the abundances of the major carbon and oxygen bearing species, the expected photochemically-produced species and magnetospheric signatures. The spectral range and resolution are tailored to separate bands belonging to up to 30 molecules and retrieve the composition and temperature structure of planetary atmospheres. The target list for EChO includes planets ranging from Jupiter-sized with equilibrium temperatures T_(eq) up to 2,000 K, to those of a few Earth masses, with T_(eq) ~300 K. The list will include planets with no Solar System analog, such as the recently discovered planets GJ1214b, whose density lies between that of terrestrial and gaseous planets, or the rocky-iron planet 55 Cnc e, with day-side temperature close to 3,000 K. As the number of detected exoplanets is growing rapidly each year, and the mass and radius of those detected steadily decreases, the target list will be constantly adjusted to include the most interesting systems. We have baselined a dispersive spectrograph design covering continuously the 0.4\u201316 \u03bcm spectral range in 6 channels (1 in the visible, 5 in the InfraRed), which allows the spectral resolution to be adapted from several tens to several hundreds, depending on the target brightness. The instrument will be mounted behind a 1.5 m class telescope, passively cooled to 50 K, with the instrument structure and optics passively cooled to ~45 K. EChO will be placed in a grand halo orbit around L2. This orbit, in combination with an optimised thermal shield design, provides a highly stable thermal environment and a high degree of visibility of the sky to observe repeatedly several tens of targets over the year. Both the baseline and alternative designs have been evaluated and no critical items with Technology Readiness Level (TRL) less than 4\u20135 have been identified. We have also undertaken a first-order cost and development plan analysis and find that EChO is easily compatible with the ESA M-class mission framework.", "date": "2012-10", "date_type": "published", "publication": "Experimental Astronomy", "volume": "34", "number": "2", "publisher": "Springer", "pagerange": "311-353", "id_number": "CaltechAUTHORS:20141217-084704264", "issn": "0922-6435", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20141217-084704264", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1007/s10686-012-9303-4", "resource_type": "article", "pub_year": "2012", "author_list": "Tinetti, G. and Yung, Y." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/0n6e1-1r629", "eprint_id": 48833, "eprint_status": "archive", "datestamp": "2023-08-22 07:05:05", "lastmod": "2023-10-17 20:28:05", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Kobayashi-Kirschvink-A", "name": { "family": "Kobayashi-Kirschvink", "given": "Atsuko" } }, { "id": "Li-King-Fai", "name": { "family": "Li", "given": "King-Fai" }, "orcid": "0000-0003-0150-2910" }, { "id": "Shia-Run-Lie", "name": { "family": "Shia", "given": "Run-Lie" }, "orcid": "0000-0003-1911-3120" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Fundamental modes of atmospheric CFC-11 from empirical mode decomposition", "ispublished": "pub", "full_text_status": "restricted", "keywords": "Chlorofluorocarbon; time series filtering; annual cycle; amplitude modulation", "note": "\u00a9 2014 World Scientific Publishing Company.\n\nReceived 27 July 2012; Revised 30 September 2012; Accepted 12 November 2012; Published 26 March 2013.\n\nKFL performed the linear filtering analysis using the computer facilities at the Atomic and Molecular Physics Laboratories, The Australian National University provided by Dr. Franklin P. Mills. This research was supported by NSF grant ATM-9903790 to the California Institute of Technology. The CFC-11 data measured by the Halocarbons and other Atmospheric Trace Species (HATS) group were obtained\nfrom http://www.esrl.noaa.gov/gmd/hats/combined/CFC11.html.", "abstract": "Following an initial growth, the concentrations of chlorofluorocarbon-11 (CFC-11) in the atmosphere started to decline in the 1990's due to world-wide legislative control on emissions. The amplitude of the annual cycle of CFC-11 was much larger in the earlier period compared with that in the later period. We apply here the Ensemble Empirical Mode Decomposition (EEMD) analysis to the CFC-11 data obtained by the U.S. National Oceanic and Atmospheric Administration. The sum of the second and third intrinsic mode functions (IMFs) represents the annual cycle, which shows that the annual cycle of CFC-11 has varied by a factor of 2\u20133 from the mid-1970's to the present over polar regions. The results provide an illustration of the power of the EEMD method in extracting a variable annual cycle from data dominated by increasing and decreasing trends. Finally, we compare the annual cycle obtained by the EEMD analysis to that obtained using conventional methods such as Fourier transforms and running averages.", "date": "2012-10", "date_type": "published", "publication": "Advances in Adaptive Data Analysis", "volume": "4", "number": "4", "publisher": "World Scientific Publishing", "pagerange": "Art. No. 1250024", "id_number": "CaltechAUTHORS:20140825-085841436", "issn": "1793-5369", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140825-085841436", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "ATM- 9903790" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1142/S1793536912500240", "resource_type": "article", "pub_year": "2012", "author_list": "Kobayashi-Kirschvink, Atsuko; Li, King-Fai; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/3brpd-vgk90", "eprint_id": 52936, "eprint_status": "archive", "datestamp": "2023-09-15 04:54:23", "lastmod": "2023-10-23 21:11:19", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Jiang-Xun", "name": { "family": "Jiang", "given": "Xun" }, "orcid": "0000-0001-8932-3807" }, { "id": "Chahine-M-T", "name": { "family": "Chahine", "given": "Moustafa T." } }, { "id": "Li-Qinbin", "name": { "family": "Li", "given": "Qinbin" } }, { "id": "Liang-Mao-Chang", "name": { "family": "Liang", "given": "Maochang" }, "orcid": "0000-0002-5294-9344" }, { "id": "Olsen-E-T", "name": { "family": "Olsen", "given": "Edward T." } }, { "id": "Chen-Luke-L", "name": { "family": "Chen", "given": "Luke L." } }, { "id": "Wang-Jingqian", "name": { "family": "Wang", "given": "Jingqian" } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "CO_2 semiannual oscillation in the middle troposphere and at the surface", "ispublished": "pub", "full_text_status": "public", "keywords": "chemistry-transport model", "note": "\u00a9 2012 American Geophysical Union.\n\nReceived 24 May 2011; revised 22 April 2012; accepted 26 June 2012; published 28 July 2012.\n\nWe thank two anonymous reviewers and the\nAssociate Editor for the helpful comments. X. Jiang is supported by JPL grant G99694. M. Liang is supported by NSC grant 98-2111-M-001-014-MY3 to Academia Sinica. Y. L. Yung is supported by JPL grant P765982\nto the California Institute of Technology.\n\nPublished - gbc1903.pdf
", "abstract": "Using in situ measurements, we find a semiannual oscillation (SAO) in the midtropospheric and surface CO_2. Chemistry transport models (2-D Caltech/JPL model, 3-D GEOS-Chem, and 3-D MOZART-2) are used to investigate possible sources for the SAO signal in the midtropospheric and surface CO_2. From model sensitivity studies, it is revealed that the SAO signal in the midtropospheric CO_2 originates mainly from surface CO_2 with a small contribution from transport fields. It is also found that the source for the SAO signal in surface CO_2 is mostly related to the CO_2 exchange between the biosphere and the atmosphere. By comparing model CO_2 with in situ CO_2 measurements at the surface, we find that models are able to capture both annual and semiannual cycles well at the surface. Model simulations of the annual and semiannual cycles of CO_2 in the tropical middle troposphere agree reasonably well with aircraft measurements.", "date": "2012-09", "date_type": "published", "publication": "Global Biogeochemical Cycles", "volume": "26", "number": "3", "publisher": "American Geophysical Union", "pagerange": "Art. No. GB3006", "id_number": "CaltechAUTHORS:20141217-083518373", "issn": "0886-6236", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20141217-083518373", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "JPL", "grant_number": "G99694" }, { "agency": "NSC", "grant_number": "98-2111-M-001-014-MY3" }, { "agency": "JPL", "grant_number": "P765982" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2011GB004118", "primary_object": { "basename": "gbc1903.pdf", "url": "https://authors.library.caltech.edu/records/3brpd-vgk90/files/gbc1903.pdf" }, "resource_type": "article", "pub_year": "2012", "author_list": "Jiang, Xun; Chahine, Moustafa T.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/z0g3b-q9271", "eprint_id": 48811, "eprint_status": "archive", "datestamp": "2023-09-15 04:49:16", "lastmod": "2023-10-23 21:10:20", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Kuai-Le", "name": { "family": "Kuai", "given": "Le" }, "orcid": "0000-0001-6406-1150" }, { "id": "Wunch-D", "name": { "family": "Wunch", "given": "Debra" }, "orcid": "0000-0002-4924-0377" }, { "id": "Shia-Run-Lie", "name": { "family": "Shia", "given": "Run-Lie" }, "orcid": "0000-0003-1911-3120" }, { "id": "Connor-B", "name": { "family": "Connor", "given": "Brian" } }, { "id": "Miller-C-E", "name": { "family": "Miller", "given": "Charles" }, "orcid": "0000-0002-9380-4838" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk" }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Vertically constrained CO_2 retrievals from TCCON measurements", "ispublished": "pub", "full_text_status": "restricted", "keywords": "TCCON; Carbon dioxide; Retrieval", "note": "\u00a9 2012 Elsevier Ltd. \n\nReceived 28 October 2011, Revised 24 April 2012, Accepted 26 April 2012, Available online 5 May 2012. \n\nThis research is supported in part by the Orbiting Carbon Observatory 2(OCO-2) project, a NASA Earth System Science Pathfinder (ESSP) mission and Project JPL. 1382974 to the California Institute of Technology. Support for TCCON and operations at Park Falls Wisconsin are provided by a grant from NASA to the California Institute of Technology (NNX11AG01G). We would like to thank Gretchen Keppel Aleks, Mimi Gerstell, Vijay Natraj, Sally Newman, Jack Margolis, Xi Zhang, King-Fai Li, and Michael Line for useful discussions and comments on the paper. Special thanks are given to G. Toon and P. Wennberg for making available their code and data, and for valuable discussions.", "abstract": "Partial column-averaged carbon dioxide (CO_2) mixing ratio in three tropospheric layers has been retrieved from Total Carbon Column Observing Network (TCCON) spectra in the 1.6 \u03bcm CO_2 absorption band. Information analysis suggests that a measurement with \u223c60 absorption lines provides three or more pieces of independent information, depending on the signal-to-noise ratio and solar zenith angle. This has been confirmed by retrievals based on synthetic data. Realistic retrievals for both total and partial column-averaged CO_2 over Park Falls, Wisconsin on July 12, 15, and August 14, 2004, agree with aircraft measurements. Furthermore, the retrieved total column averages are always underestimated by less than 1%. The results above provide a basis for CO_2 profile retrievals using ground-based observations in the near-infrared region.", "date": "2012-09", "date_type": "published", "publication": "Journal of Quantitative Spectroscopy and Radiative Transfer", "volume": "113", "number": "14", "publisher": "Elsevier", "pagerange": "1753-1761", "id_number": "CaltechAUTHORS:20140822-111011677", "issn": "0022-4073", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140822-111011677", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Orbiting Carbon Observatory 2(OCO-2) project" }, { "agency": "JPL", "grant_number": "1382974" }, { "agency": "NASA", "grant_number": "NNX11AG01G" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/j.jqsrt.2012.04.024", "resource_type": "article", "pub_year": "2012", "author_list": "Kuai, Le; Wunch, Debra; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/eyay1-e7a14", "eprint_id": 31912, "eprint_status": "archive", "datestamp": "2023-08-22 06:00:58", "lastmod": "2023-10-17 21:41:53", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Boxe-C-S", "name": { "family": "Boxe", "given": "C. S." } }, { "id": "Hand-K-P", "name": { "family": "Hand", "given": "K. P." }, "orcid": "0000-0002-3225-9426" }, { "id": "Nealson-K-H", "name": { "family": "Nealson", "given": "K. H." }, "orcid": "0000-0001-5189-3732" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Y. L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Yen-Albert-S", "name": { "family": "Yen", "given": "A. S." } }, { "id": "Saiz-Lopez-A", "name": { "family": "Saiz-Lopez", "given": "A." } } ] }, "title": "Adsorbed water and thin liquid films on Mars", "ispublished": "pub", "full_text_status": "public", "keywords": "thin liquid films; adsorbed water; Mars; subsurface; interfacial; biological activity; life", "note": "\u00a9 2012 Cambridge University Press. \n\nReceived 19 October 2010; accepted 20 January 2012; first published online 24 February 2012.\n\nPublished - Boxe2012p18384Int_J_Astrobiol.pdf
", "abstract": "At present, bulk liquid water on the surface and near-subsurface of Mars does not exist due to the scarcity of condensed- and gas-phase water, pressure and temperature constraints. Given that the nuclei of soil and ice, that is, the soil solid and ice lattice, respectively, are coated with adsorbed and/or thin liquid films of water well below 273 K and the availability of water limits biological activity, we quantify lower and upper limits for the thickness of such adsorbed/water films on the surface of the Martian regolith and for subsurface ice. These limits were calculated based on experimental and theoretical data for pure water ice and water ice containing impurities, where water ice containing impurities exhibit thin liquid film enhancements, ranging from 3 to 90. Close to the cold limit of water stability (i.e. 273 K), thin liquid film thicknesses at the surface of the Martian regolith is 0.06 nm (pure water ice) and ranges from 0.2 to 5 nm (water ice with impurities). An adsorbed water layer of 0.06 nm implies a dessicated surface as the thickness of one monolayer of water is 0.3 nm but represents 0.001\u20130.02% of the Martian atmospheric water vapour inventory. Taking into account the specific surface area (SSA) of surface-soil (i.e. top 1 mm of regolith and 0.06 nm adsorbed water layer), shows Martian surface-soil may contain interfacial water that represents 6\u201366% of the upper- and lower-limit atmospheric water vapour inventory and almost four times and 33%, the lower- and upper-limit Martian atmospheric water vapour inventory. Similarly, taking the SSA of Martian soil, the top 1 mm or regolith at 5 nm thin liquid water thickness, yields 1.10\u00d710^(13) and 6.50\u00d710^(13) litres of waters, respectively, 55\u2013325 times larger than Mars' atmospheric water vapour inventory. Film thicknesses of 0.2 and 5 nm represent 2.3\u00d710^4 \u2013 1.5\u00d710^6 litres of water, which is 6.0\u00d710^(\u22127) \u2013 4.0\u00d710^(\u22124)%, respectively, of a 10 pr \u03bcm water vapour column, and 3.0\u00d710^(\u22126) \u2013 4.0\u00d710^(\u22124)% and 6.0\u00d710^(\u22126)\u20138.0\u00d710^(\u22124)%, respectively, of the Martian atmospheric water vapour inventory. Thin liquid film thicknesses on/in subsurface ice were investigated via two scenarios: (i) under the idealistic case where it is assumed that the diurnal thermal wave is equal to the temperature of ice tens of centimetres below the surface, allowing for such ice to experience temperatures close to 273 K and (ii) under the, likely, realistic scenario where the diurnal thermal wave allows for the maximum subsurface ice temperature of 235 K at 1 m depth between 30\u00b0N and 30\u00b0S. Scenario 1 yields thin liquid film thicknesses ranging from 11 to 90 nm; these amounts represent 4\u00d710^(6) \u2013 3.0\u00d710^7 litres of water. For pure water ice, Scenario 2 reveals that the thickness of thin liquid films contained on/within Martian subsurface is less than 1.2 nm, several molecular layers thick. Conversely, via the effect of impurities at 235 K allows for a thin liquid film thickness on/within subsurface ice of 0.5 nm, corresponding to 6.0\u00d710^4 litres of water. The existence of thin films on Mars is supported by data from the Mars Exploration Rovers (MERs) Spirit and Opportunity's Alpha Proton X-ray Spectrometer instrumentation, which have detected increased levels of bromine beneath the immediate surface, suggestive of the mobilization of soluble salts by thin films of liquid water towards local cold traps. These findings show that biological activity on the Martian surface and subsurface is not limited by nanometre dimensions of available water", "date": "2012-07", "date_type": "published", "publication": "International Journal of Astrobiology", "volume": "11", "number": "3", "publisher": "Cambridge University Press", "pagerange": "169-175", "id_number": "CaltechAUTHORS:20120614-131101421", "issn": "1473-5504", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20120614-131101421", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1017/S1473550412000080", "primary_object": { "basename": "Boxe2012p18384Int_J_Astrobiol.pdf", "url": "https://authors.library.caltech.edu/records/eyay1-e7a14/files/Boxe2012p18384Int_J_Astrobiol.pdf" }, "resource_type": "article", "pub_year": "2012", "author_list": "Boxe, C. S.; Hand, K. P.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/pcpbw-esr28", "eprint_id": 33292, "eprint_status": "archive", "datestamp": "2023-08-22 05:35:49", "lastmod": "2023-10-18 18:57:50", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Stock-J-W", "name": { "family": "Stock", "given": "Joachim W." } }, { "id": "Boxe-C-S", "name": { "family": "Boxe", "given": "Christopher S." } }, { "id": "Lehmann-R", "name": { "family": "Lehmann", "given": "Ralph" } }, { "id": "Grenfell-J-L", "name": { "family": "Grenfell", "given": "J. Lee" } }, { "id": "Patzer-A-B-C", "name": { "family": "Patzer", "given": "A. Beate C." } }, { "id": "Rauer-H", "name": { "family": "Rauer", "given": "Heike" } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Chemical pathway analysis of the Martian atmosphere: CO_2-formation pathways", "ispublished": "pub", "full_text_status": "restricted", "keywords": "Atmospheres, Chemistry; Atmospheres, Composition; Mars; Mars, Atmosphere; Photochemistry", "note": "\u00a9 2012 Elsevier. Received 19 October 2011. Revised 26 January 2012. Accepted 10 February 2012. Available online 22 February 2012. This research has been partly supported by the Helmholtz Association through the research alliance \"Planetary Evolution and Life\".", "abstract": "The chemical composition of a planetary atmosphere plays an important role for atmospheric structure, stability, and evolution. Potentially complex interactions between chemical species do not often allow for an easy understanding of the underlying chemical mechanisms governing the atmospheric composition. In particular, trace species can affect the abundance of major species by acting in catalytic cycles. On Mars, such cycles even control the abundance of its main atmospheric constituent CO_2. The identification of catalytic cycles (or more generally chemical pathways) by hand is quite demanding. Hence, the application of computer algorithms is beneficial in order to analyze complex chemical reaction networks. Here, we have performed the first automated quantified chemical pathways analysis of the Martian atmosphere with respect to CO_2-production in a given reaction system. For this, we applied the Pathway Analysis Program (PAP) to output data from the Caltech/JPL photochemical Mars model. All dominant chemical pathways directly related to the global CO_2-production have been quantified as a function of height up to 86 km. We quantitatively show that CO_2-production is dominated by chemical pathways involving HO_x and O_x. In addition, we find that NO_x in combination with HO_x and O_x exhibits a non-negligible contribution to CO_2-production, especially in Mars' lower atmosphere. This study reveals that only a small number of chemical pathways contribute significantly to the atmospheric abundance of CO_2 on Mars; their contributions to CO_2-production vary considerably with altitude. This analysis also endorses the importance of transport processes in governing CO_2-stability in the Martian atmosphere. Lastly, we identify a previously unknown chemical pathway involving HO_x, O_x, and HO_2-photodissociation, contributing 8% towards global CO_2-production by chemical pathways using recommended up-to-date values for reaction rate coefficients.", "date": "2012-05", "date_type": "published", "publication": "Icarus", "volume": "219", "number": "1", "publisher": "Elsevier", "pagerange": "13-24", "id_number": "CaltechAUTHORS:20120817-110427324", "issn": "0019-1035", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20120817-110427324", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Helmholtz Association" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/j.icarus.2012.02.010", "resource_type": "article", "pub_year": "2012", "author_list": "Stock, Joachim W.; Boxe, Christopher S.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/9d0e8-4f789", "eprint_id": 31294, "eprint_status": "archive", "datestamp": "2023-08-22 05:26:36", "lastmod": "2023-10-17 15:44:44", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Line-M-R", "name": { "family": "Line", "given": "Michael R." }, "orcid": "0000-0002-2338-476X" }, { "id": "Zhang-Xi", "name": { "family": "Zhang", "given": "Xi" } }, { "id": "Vasisht-G", "name": { "family": "Vasisht", "given": "Gautam" }, "orcid": "0000-0002-1871-6264" }, { "id": "Natraj-V", "name": { "family": "Natraj", "given": "Vijay" }, "orcid": "0000-0003-3154-9429" }, { "id": "Chen-Pin", "name": { "family": "Chen", "given": "Pin" } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Information Content of Exoplanetary Transit Spectra: An Initial Look", "ispublished": "pub", "full_text_status": "public", "keywords": "methods: data analysis; planets and satellites: atmospheres; planets and satellites: individual (HD189733b); radiative transfer", "note": "\u00a9 2012 American Astronomical Society.\n\nReceived 2011 November 9; accepted 2012 February 10; published 2012 March 26.\n\nWe thank Zhan Su, Aaron Wolf, Konstantin Batygin,\nAlejandro Soto, Run-Lie Shia, Leigh Fletcher, Kuai Le, Heather Knutson, Mimi Gerstell, Linda Brown, and the Yuk Yung group for reading the article and many useful discussions. M. Line is supported by the JPL Graduate Fellowship funded by the JPL Research and Technology Development Program. X.Z. and Y.L.Y. are supported by a grant from the PATM program of NASA to the California Institute of Technology. P. Chen and G. Vasisht are supported by the JPL Research & Technology Development Program, and contributions here in were supported by\nthe Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration.\n\nPublished - Line2012p17950Astrophys_J.pdf
Accepted Version - 1111.2612.pdf
", "abstract": "It has been shown that spectroscopy of transiting extrasolar planets can potentially provide a wealth of information about their atmospheres. Herein, we set up the inverse problem in spectroscopic retrieval. We use nonlinear optimal estimation to retrieve the atmospheric state (pioneered for Earth sounding by Rodgers). The formulation quantifies the degrees of freedom and information content of the spectrum with respect to geophysical parameters; herein, we focus specifically on temperature and composition. First, we apply the technique to synthetic near-infrared spectra and explore the influence of spectral signal-to-noise ratio and resolution (the two important parameters when designing a future instrument) on the information content of the data. As expected, we find that the number of retrievable parameters increases with increasing signal-to-noise ratio and resolution, although the gains quickly level off for large values. Second, we apply the methods to the previously studied dayside near-infrared emission spectrum of HD 189733b and compare the results of our retrieval with those obtained by others.", "date": "2012-04-10", "date_type": "published", "publication": "Astrophysical Journal", "volume": "749", "number": "1", "publisher": "American Astronomical Society", "pagerange": "93", "id_number": "CaltechAUTHORS:20120503-150855437", "issn": "0004-637X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20120503-150855437", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "JPL Graduate Fellowship" }, { "agency": "JPL Research and Technology Development Program" }, { "agency": "NASA/JPL/Caltech" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1088/0004-637X/749/1/93", "primary_object": { "basename": "1111.2612.pdf", "url": "https://authors.library.caltech.edu/records/9d0e8-4f789/files/1111.2612.pdf" }, "related_objects": [ { "basename": "Line2012p17950Astrophys_J.pdf", "url": "https://authors.library.caltech.edu/records/9d0e8-4f789/files/Line2012p17950Astrophys_J.pdf" } ], "resource_type": "article", "pub_year": "2012", "author_list": "Line, Michael R.; Zhang, Xi; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/20zc3-r9588", "eprint_id": 47265, "eprint_status": "archive", "datestamp": "2023-08-22 05:25:16", "lastmod": "2023-10-26 20:27:12", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Crisp-D", "name": { "family": "Crisp", "given": "D." }, "orcid": "0000-0002-4573-9998" }, { "id": "Frankenberg-C", "name": { "family": "Frankenberg", "given": "C." }, "orcid": "0000-0002-0546-5857" }, { "id": "Messerschmidt-J", "name": { "family": "Messerschmidt", "given": "J." } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Wunch-D", "name": { "family": "Wunch", "given": "D." }, "orcid": "0000-0002-4924-0377" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Y. L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "The ACOS CO_2 retrieval algorithm \u2013 Part II: Global X_(CO_2) data characterization", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2012 Author(s). This work is distributed under the Creative Commons Attribution 3.0 License. Published by Copernicus Publications on behalf of the European Geosciences Union. \n\nReceived: 24 November 2011; Published in Atmos. Meas. Tech.; Discuss.: 3 January 2012; Revised: 1 March 2012; Accepted: 13 March 2012; Published: 2 April 2012. \n\nThe GOSAT spectra were provided to the ACOS Team through a GOSAT Research Announcement (RA) agreement between the California Institute of Technology and the three parties, JAXA, NIES and the MOE. The meteorological data used to initialize the retrievals and as a reference for comparison with the surface pressure results were based on data and products of the European Centre for Medium-Range Weather Forecasts (ECMWF). TCCON data were obtained from the TCCON Data Archive, operated by the California Institute of Technology from the website at http://tccon.ipac.caltech.edu/. Part of the research described here was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration.\n\nPublished - amt-5-687-2012.pdf
", "abstract": "Here, we report preliminary estimates of the column averaged carbon dioxide (CO_2) dry air mole fraction, X_(CO_2), retrieved from spectra recorded over land by the Greenhouse gases Observing Satellite, GOSAT (nicknamed \"Ibuki\"), using retrieval methods originally developed for the NASA Orbiting Carbon Observatory (OCO) mission. After screening for clouds and other known error sources, these retrievals reproduce much of the expected structure in the global X_(CO_2) field, including its variation with latitude and season. However, low yields of retrieved X_(CO_2) over persistently cloudy areas and ice covered surfaces at high latitudes limit the coverage of some geographic regions, even on seasonal time scales. Comparisons of early GOSAT X_(CO_2) retrievals with X_(CO_2) estimates from the Total Carbon Column Observing Network (TCCON) revealed a global, \u22122% (7\u20138 parts per million, ppm, with respect to dry air) X_(CO_2) bias and 2 to 3 times more variance in the GOSAT retrievals. About half of the global X_(CO_2) bias is associated with a systematic, 1% overestimate in the retrieved air mass, first identified as a global +10 hPa bias in the retrieved surface pressure. This error has been attributed to errors in the O_2 A-band absorption cross sections. Much of the remaining bias and spurious variance in the GOSAT X_(CO_2) retrievals has been traced to uncertainties in the instrument's calibration, oversimplified methods for generating O_2 and CO_2 absorption cross sections, and other subtle errors in the implementation of the retrieval algorithm. Many of these deficiencies have been addressed in the most recent version (Build 2.9) of the retrieval algorithm, which produces negligible bias in X_(CO_2) on global scales as well as a ~30% reduction in variance. Comparisons with TCCON measurements indicate that regional scale biases remain, but these could be reduced by applying empirical corrections like those described by Wunch et al. (2011b). We recommend that such corrections be applied before these data are used in source sink inversion studies to minimize spurious fluxes associated with known biases. These and other lessons learned from the analysis of GOSAT data are expected to accelerate the delivery of high quality data products from the Orbiting Carbon Observatory-2 (OCO-2), once that satellite is successfully launched and inserted into orbit.", "date": "2012-04-02", "date_type": "published", "publication": "Atmospheric Measurement Techniques", "volume": "5", "number": "4", "publisher": "European Geosciences Union", "pagerange": "687-707", "id_number": "CaltechAUTHORS:20140716-110412369", "issn": "1867-1381", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140716-110412369", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA/JPL/Caltech" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/amt-5-687-2012", "primary_object": { "basename": "amt-5-687-2012.pdf", "url": "https://authors.library.caltech.edu/records/20zc3-r9588/files/amt-5-687-2012.pdf" }, "resource_type": "article", "pub_year": "2012", "author_list": "Crisp, D.; Frankenberg, C.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/st58t-9ke98", "eprint_id": 30213, "eprint_status": "archive", "datestamp": "2023-08-22 05:17:36", "lastmod": "2023-10-17 15:33:22", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Boxe-C-S", "name": { "family": "Boxe", "given": "C. S." } }, { "id": "Hand-K-P", "name": { "family": "Hand", "given": "K. P." }, "orcid": "0000-0002-3225-9426" }, { "id": "Nealson-K-H", "name": { "family": "Nealson", "given": "K. H." }, "orcid": "0000-0001-5189-3732" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Y. L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Saiz-Lopez-A", "name": { "family": "Saiz-Lopez", "given": "A." } } ] }, "title": "An active nitrogen cycle on Mars sufficient to support a subsurface biosphere", "ispublished": "pub", "full_text_status": "public", "keywords": "Mars, nitrogen, nitrogen fixation, klingler hypothesis, free energy.", "note": "\u00a9 2012 Cambridge University Press. \n\nReceived 23 March 2011, accepted 4 December 2011, first published online 16 January 2012.\n\nPublished - Boxe2012p17592Int_J_Astrobiol.pdf
", "abstract": "Mars' total atmospheric nitrogen content is 0.2 mbar. One-dimensional (1D) photochemical simulations of Mars' atmosphere show that nitric acid (HNO_3(g)), the most soluble nitrogen oxide, is the principal reservoir species for nitrogen in its lower atmosphere, which amounts to a steady-state value of 6\u00d710^(\u22122) kg or 4 moles, conditions of severe nitrogen deficiency. Mars could, however, support \u223c10^(15) kg of biomass (\u223c1 kg N m^(\u22122)) from its current atmospheric nitrogen inventory. The terrestrial mass ratio of nitrogen in biomass to that in the atmosphere is \u223c10^(\u22125); applying this ratio to Mars yields \u223c10^(10) kg of total biomass \u2013 also, conditions of severe nitrogen deficiency. These amounts, however, are lower limits as the maximum surface-sink of atmospheric nitrogen is 2.8 mbar (9\u00d710^(15) kg of N), which indicates, in contradistinction to the Klingler et al. (1989), that biological metabolism would not be inhibited in the subsurface of Mars. Within this context, we explore HNO_3 deposition on Mars' surface (i.e. soil and ice-covered regions) on pure water metastable thin liquid films. We show for the first time that the negative change in Gibbs free energy increases with decreasing HNO_3(g) (NO_3^\u2212(aq)) in metastable thin liquid films that may exist on Mars' surface. We also show that additional reaction pathways are exergonic and may proceed spontaneously, thus providing an ample source of energy for nitrogen fixation on Mars. Lastly, we explore the dissociation of HNO_3(g) to form NO_3^\u2212(aq) in metastable thin liquid films on the Martian surface via condensed phase simulations. These simulations show that photochemically produced fixed nitrogen species are not only released from the Martian surface to the gas-phase, but more importantly, transported to lower depths from the Martian surface in transient thin liquid films. A putative biotic layer at 10 m depth would produce HNO_3 and N_2 sinks of \u221254 and \u22125\u00d710^(12) molecules cm^(\u22122) s^(\u22121), respectively, which is an ample supply of available nitrogen that can be efficiently transported to the subsurface. The downward transport as well as the release to the atmosphere of photochemically produced fixed nitrogen species (e.g. NO_2^\u2212, NO and NO_2) suggests the existence of a transient but active nitrogen cycle on Mars.", "date": "2012-04", "date_type": "published", "publication": "International Journal of Astrobiology", "volume": "11", "number": "2", "publisher": "Cambridge University Press", "pagerange": "109-115", "id_number": "CaltechAUTHORS:20120420-091645136", "issn": "1473-5504", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20120420-091645136", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1017/S1473550411000401", "primary_object": { "basename": "Boxe2012p17592Int_J_Astrobiol.pdf", "url": "https://authors.library.caltech.edu/records/st58t-9ke98/files/Boxe2012p17592Int_J_Astrobiol.pdf" }, "resource_type": "article", "pub_year": "2012", "author_list": "Boxe, C. S.; Hand, K. P.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/9qczg-0aq86", "eprint_id": 31633, "eprint_status": "archive", "datestamp": "2023-08-22 05:20:50", "lastmod": "2023-10-17 18:44:08", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Trainer-M-G", "name": { "family": "Trainer", "given": "Melissa G." } }, { "id": "Jimenez-J-L", "name": { "family": "Jimenez", "given": "Jose L." }, "orcid": "0000-0001-6203-1847" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Toon-O-B", "name": { "family": "Toon", "given": "Owen B." } }, { "id": "Tolbert-M-A", "name": { "family": "Tolbert", "given": "Margaret A." } } ] }, "title": "Nitrogen Incorporation in CH_4-N_2 Photochemical Aerosol Produced by Far Ultraviolet Irradiation", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2012 Mary Ann Liebert, Inc. Submitted 14 December 2011.\nAccepted 20 February 2012. M.G.T. thanks R. Lessard, C. Hasenkopf, and D. Day for help with control experiments. Y.L.Y. thanks K. Bayes, S. Sander, and W. DeMore for discussion of the kinetics of CH reactions. This work was funded by NASA grants NNX07AV55G, NNX11AD82G, and NNX08AG93G. The development of the HR-ToF-AMS and its analysis software was partially funded by NSF ATM-0449815 and NOAA NA08OAR4310565. Y.L.Y. was supported by NASA grant\nNX09AB72G to the California Institute of Technology.\nDisclosure Statement\nNo competing financial interests exist.\n\nPublished - Trainer2012p18215Astrobiology.pdf
", "abstract": "Nitrile incorporation into Titan aerosol accompanying hydrocarbon chemistry is thought to be driven by extreme UV wavelengths (\u03bb<120\u2009nm) or magnetospheric electrons in the outer reaches of the atmosphere. Far UV radiation (120\u2013200\u2009nm), which is transmitted down to the stratosphere of Titan, is expected to affect hydrocarbon chemistry only and not initiate the formation of nitrogenated species. We examined the chemical properties of photochemical aerosol produced at far UV wavelengths, using a high-resolution time-of-flight aerosol mass spectrometer (HR-ToF-AMS), which allows for elemental analysis of particle-phase products. Our results show that aerosol formed from CH_4/N_2 photochemistry contains a surprising amount of nitrogen, up to 16% by mass, a result of photolysis in the far UV. The proportion of nitrogenated organics to hydrocarbon species is shown to be correlated with that of N_2 in the irradiated gas. The aerosol mass greatly decreases when N_2 is removed, which indicates that N_2 plays a major role in aerosol production. Because direct dissociation of N_2 is highly improbable given the immeasurably low cross section at the wavelengths studied, the chemical activation of N_2 must occur via another pathway. Any chemical activation of N_2 at wavelengths >120\u2009nm is presently unaccounted for in atmospheric photochemical models. We suggest that reaction with CH radicals produced from CH_4 photolysis may provide a mechanism for incorporating N into the molecular structure of the aerosol. Further work is needed to understand the chemistry involved, as these processes may have significant implications for how we view prebiotic chemistry on early Earth and similar planets. Key Words: Titan\u2014Photochemical aerosol\u2014CH_4-N_2 photolysis\u2014Far UV\u2014Nitrogen activation.", "date": "2012-04", "date_type": "published", "publication": "Astrobiology", "volume": "12", "number": "4", "publisher": "Mary Ann Liebert", "pagerange": "315-326", "id_number": "CaltechAUTHORS:20120524-114615646", "issn": "1531-1074", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20120524-114615646", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NNX07AV55G" }, { "agency": "NASA", "grant_number": "NNX11AD82G" }, { "agency": "NASA", "grant_number": "NNX08AG93G" }, { "agency": "NSF", "grant_number": "ATM-0449815" }, { "agency": "National Oceanic and Atmospheric Administration (NOAA)", "grant_number": "NA08OAR4310565" }, { "agency": "NASA", "grant_number": "NX09AB72G" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1089/ast.2011.0754", "pmcid": "PMC3330558", "primary_object": { "basename": "Trainer2012p18215Astrobiology.pdf", "url": "https://authors.library.caltech.edu/records/9qczg-0aq86/files/Trainer2012p18215Astrobiology.pdf" }, "resource_type": "article", "pub_year": "2012", "author_list": "Trainer, Melissa G.; Jimenez, Jose L.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/1w8td-y5w74", "eprint_id": 29521, "eprint_status": "archive", "datestamp": "2023-08-22 04:49:05", "lastmod": "2023-10-24 22:16:38", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Zhang-Xi", "name": { "family": "Zhang", "given": "Xi" } }, { "id": "Liang-Mao-Chang", "name": { "family": "Liang", "given": "Mao Chang" }, "orcid": "0000-0002-5294-9344" }, { "id": "Mills-F-P", "name": { "family": "Mills", "given": "Franklin P." } }, { "id": "Belyaev-D-A", "name": { "family": "Belyaev", "given": "Denis A." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "\u00adYuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Sulfur chemistry in the middle atmosphere of Venus", "ispublished": "pub", "full_text_status": "restricted", "keywords": "Venus, Atmosphere; Atmospheres, Chemistry; Photochemistry; Atmospheres, Composition", "note": "\u00a9 2011 Elsevier Inc. Available online 14 July 2011. We thank E. Marcq for sharing his latest work with us and for\nhelpful discussions, C. Parkinson, S. Bougher and A. Brecht for providing us the recent VTGCM results, A. Ingersoll and D. Yang for insightful comments, R. Zeng for checking the chemical reaction table, M. Gerstell, M. Line and other members of Yung's group at Caltech for reading the manuscript. We are indebted to T. Clancy for pointing out the importance of Sx aerosols as a potential source of SO2 in the mesosphere of Venus. We acknowledge two anonymous reviewers for their helpful comments. This research was supported by NASA grant NNX07AI63G to the California Institute of Technology. M. C. Liang was funded by NSC Grant 98-2111-M-001-014-MY3 to Academia Sinica. F.P. Mills was supported by grants under the Australian Research Council Discovery Projects and Linkage International schemes. D. A. Belyaev acknowledges support from CNES for a post-doc position at LATMOS.", "abstract": "Venus Express measurements of the vertical profiles of SO and SO_2 in the middle atmosphere of Venus provide an opportunity to revisit the sulfur chemistry above the middle cloud tops (\u223c58 km). A one dimensional photochemistry-diffusion model is used to simulate the behavior of the whole chemical system including oxygen-, hydrogen-, chlorine-, sulfur-, and nitrogen-bearing species. A sulfur source is required to explain the SO_2 inversion layer above 80 km. The evaporation of the aerosols composed of sulfuric acid (model A) or polysulfur (model B) above 90 km could provide the sulfur source. Measurements of SO_3 and SO (\u03b1^1\u0394 \u2192 X^3\u03a3^-) emission at 1.7 \u03bcm may be the key to distinguish between the two models.", "date": "2012-02", "date_type": "published", "publication": "Icarus", "volume": "217", "number": "2", "publisher": "Elsevier", "pagerange": "714-739", "id_number": "CaltechAUTHORS:20120229-090823769", "issn": "0019-1035", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20120229-090823769", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NNX07AI63G" }, { "agency": "NSC", "grant_number": "98-2111-M- 001-014-MY3" }, { "agency": "Australian Research Council Discovery Project" }, { "agency": "CNES (France)" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/j.icarus.2011.06.016", "resource_type": "article", "pub_year": "2012", "author_list": "Zhang, Xi; Liang, Mao Chang; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/09evk-t5h35", "eprint_id": 29514, "eprint_status": "archive", "datestamp": "2023-08-22 04:48:57", "lastmod": "2023-10-24 22:16:22", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Belyaev-D-A", "name": { "family": "Belyaev", "given": "Denis A." } }, { "id": "Montmessin-F", "name": { "family": "Montmessin", "given": "Franck" } }, { "id": "Bertaux-J-L", "name": { "family": "Bertaux", "given": "Jean-Loup" } }, { "id": "Mahieux-A", "name": { "family": "Mahieux", "given": "Arnaud" } }, { "id": "Fedorova-A-A", "name": { "family": "Fedorova", "given": "Anna A." } }, { "id": "Korablev-O-I", "name": { "family": "Korablev", "given": "Oleg I." } }, { "id": "Marcq-E", "name": { "family": "Marcq", "given": "Emmanuel" } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Zhang-X", "name": { "family": "Zhang", "given": "Xi" } } ] }, "title": "Vertical profiling of SO_2 and SO above Venus' clouds by SPICAV/SOIR solar occultations", "ispublished": "pub", "full_text_status": "restricted", "keywords": "Venus\nVenus, Atmosphere\nSpectroscopy\nPhotochemistry", "note": "\u00a9 2011 Elsevier Inc. Available online 5 October 2011. Venus Express is a space mission from the European Space\nAgency (ESA). We wish to thank all ESA members who participated in this successful mission, and in particular H. Svedhem and D. Titov. We also thank Astrium for the design and construction of the spacecraft. We thank our collaborators at LATMOS/France, BIRA/Belgium and IKI/Russia for the design and fabrication of the instrument. We thank CNRS and CNES for funding SPICAV/SOIR in France, the Belgian Federal Science Policy Office, the European Space Agency (ESA, PRODEX program), Roscosmoc and the Russian Academy of Sciences. Oleg Korablev and Anna Fedorova acknowledge support from RFBR Grant # 10-02-93116. Denis Belyaev acknowledges support from CNES for a post-doc position at LATMOS. Xi Zhang and Yuk L. Yung were supported by NASA Grant NNX07AI63G to the California Institute of Technology.", "abstract": "New measurements of sulfur dioxide (SO2) and monoxide (SO) in the atmosphere of Venus by SPICAV/SOIR instrument onboard Venus Express orbiter provide ample statistics to study the behavior of these gases above Venus' clouds. The instrument (a set of three spectrometers) is capable to sound atmospheric structure above the clouds in several observation modes (nadir, solar and stellar occultations) either in the UV or in the near IR spectral ranges. We present the results from solar occultations in the absorption ranges of SO_2 (190\u2013230 nm, and at 4 \u03bcm) and SO (190\u2013230 nm). The dioxide was detected by the SOIR spectrometer at the altitudes of 65\u201380 km in the IR and by the SPICAV spectrometer at 85\u2013105 km in the UV. The monoxide's absorption was measured only by SPICAV at 85\u2013105 km. We analyzed 39 sessions of solar occultation, where boresights of both spectrometers are oriented identically, to provide complete vertical profiling of SO_2 of the Venus' mesosphere (65\u2013105 km). Here we report the first firm detection and measurements of two SO_2 layers. In the lower layer SO_2 mixing ratio is within 0.02\u20130.5 ppmv. The upper layer, also conceivable from microwave measurements by Sandor et al. (Sandor, B.J., Todd Clancy, R., Moriarty-Schieven, G., Mills, F.P. [2010]. Icarus 208, 49\u201360) is characterized by SO_2 increasing with the altitude from 0.05 to 2 ppmv, and the [SO_2]/[SO] ratio varying from 1 to 5. The presence of the high-altitude SO_x species could be explained by H_2SO_4 photodissociation under somewhat warmer temperature conditions in Venus mesosphere. At 90\u2013100 km the content of the sulfur dioxide correlates with temperature increasing from 0.1 ppmv at 165\u2013170 K to 0.5\u20131 ppmv at 190\u2013192 K. It supports the hypothesis of SO_2 production by the evaporation of H_2SO_4 from droplets and its subsequent photolysis at around 100 km.", "date": "2012-02", "date_type": "published", "publication": "Icarus", "volume": "217", "number": "2", "publisher": "Elsevier", "pagerange": "740-751", "id_number": "CaltechAUTHORS:20120229-074752024", "issn": "0019-1035", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20120229-074752024", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "CNRS (France)" }, { "agency": "CNES (France)" }, { "agency": "Belgian Federal Science Policy Office" }, { "agency": "European Space Agency" }, { "agency": "RFBR Grant", "grant_number": "10-02-93116" }, { "agency": "NASA", "grant_number": "NNX07AI63G" }, { "agency": "Russian Academy of Sciences" }, { "agency": "Roscosmoc" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/j.icarus.2011.09.025", "resource_type": "article", "pub_year": "2012", "author_list": "Belyaev, Denis A.; Montmessin, Franck; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/0f25d-78536", "eprint_id": 48820, "eprint_status": "archive", "datestamp": "2023-08-22 04:42:30", "lastmod": "2023-10-17 20:27:29", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Li-King-Fai", "name": { "family": "Li", "given": "K.-F." }, "orcid": "0000-0003-0150-2910" }, { "id": "Tian-Baijun", "name": { "family": "Tian", "given": "B." } }, { "id": "Waliser-D-E", "name": { "family": "Waliser", "given": "D. E." } }, { "id": "Schwartz-M-J", "name": { "family": "Schwartz", "given": "M. J." } }, { "id": "Neu-J-L", "name": { "family": "Neu", "given": "J. L." } }, { "id": "Worden-J-R", "name": { "family": "Worden", "given": "J. R." }, "orcid": "0000-0003-0257-9549" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Y. L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Vertical structure of MJO-related subtropical ozone variations from MLS, TES, and SHADOZ data", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 Author(s) 2012. Published by Copernicus Publications on behalf of the European Geosciences Union. This work is distributed under the Creative Commons Attribution 3.0 License. \n\nReceived: 5 August 2011; Published in Atmos. Chem. Phys. Discuss.: 31 August 2011 Revised: 21 December 2011; Accepted: 21 December 2011; Published: 6 January 2012.\n\nThis research was supported in part by the National\nScience Foundation (NSF) grant ATM-0840787 to California\nInstitute of Technology (Caltech) and ATM-0840755 to University of California, Los Angeles. Part of this research was carried out at Jet Propulsion Laboratory, Caltech, under a contract with National Aeronautics and Space Administration. ERA-Interim data were obtained\nfrom the ECMWF Data Server (http://data.ecmwf.int/data/).\nThe RMM index was obtained from the Bureau of Meteorology\nwebsite (http://www.bom.gov.au/climate/mjo/). The\nSHADOZ data were obtained from SHADOZ data server\n(http://croc.gsfc.nasa.gov/shadoz/).\nEdited by: G. Vaughan\n\nPublished - acp-12-425-2012.pdf
", "abstract": "Tian et al. (2007) found that the MJO-related total column ozone (O_3) anomalies of 10 DU (peak-to-trough) are mainly evident over the subtropics and dynamically driven by the vertical movement of the subtropical tropopause layer. It was then hypothesized that the subtropical total column O_3 anomalies are primarily associated with the O_3 variability in the stratosphere rather the troposphere. In this paper, we investigate the vertical structure of MJO-related subtropical O_3 variations using the vertical O_3 profiles from the Aura Microwave Limb Sounder (MLS) and Tropospheric Emission Spectrometer (TES), as well as in-situ measurements by the Southern Hemisphere Additional Ozonesondes (SHADOZ) project. Our analysis indicates that the subtropical O_3 anomalies maximize approximately in the lower stratosphere (60\u2013100 hPa). Furthermore, the spatial-temporal patterns of the subtropical O_3 anomalies in the lower stratosphere are very similar to that of the total column. In particular, they are both dynamically driven by the vertical movement of subtropical tropopause. The subtropical partial O_3 column anomalies between 30\u2013200 hPa accounts for more than 50 % of the total O_3 column anomalies. TES measurements show that at most 27 % of the total O_3 column anomalies are contributed by the tropospheric components. This indicates that the subtropical total column O_3 anomalies are mostly from the O3 anomalies in the lower stratosphere, which supports the hypothesis of Tian et al. (2007). The strong connection between the intraseasonal subtropical stratospheric O_3 variations and the MJO implies that the stratospheric O_3 variations may be predictable with similar lead times over the subtropics. Future work could involve a similar study or an O_3 budget analysis using a sophisticated chemical transport model in the near-equatorial regions where the observed MJO signals of total column O_3 are weak.", "date": "2012-01-06", "date_type": "published", "publication": "Atmospheric Chemistry and Physics", "volume": "12", "number": "1", "publisher": "European Geosciences Union", "pagerange": "425-436", "id_number": "CaltechAUTHORS:20140822-131217965", "issn": "1680-7316", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140822-131217965", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "ATM-0840787" }, { "agency": "NSF", "grant_number": "ATM-0840755" }, { "agency": "NASA" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/acp-12-425-2012", "primary_object": { "basename": "acp-12-425-2012.pdf", "url": "https://authors.library.caltech.edu/records/0f25d-78536/files/acp-12-425-2012.pdf" }, "resource_type": "article", "pub_year": "2012", "author_list": "Li, K.-F.; Tian, B.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/jmr96-9nq34", "eprint_id": 29231, "eprint_status": "archive", "datestamp": "2023-08-22 04:35:48", "lastmod": "2023-10-24 22:00:55", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Huang-X", "name": { "family": "Huang", "given": "Xianglei" } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk Ling" }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Effects of Atmospheric Absorption of Incoming Radiation on the Radiation Limit of the Troposphere: Reply", "ispublished": "pub", "full_text_status": "public", "keywords": "Radiative transfer", "note": "\u00a9 2012 American Meteorological Society.\nManuscript received 25 June 2011, in final form 3 August 2011.\n\nPublished - Huang2012p17055J_Atmos_Sci.pdf
", "abstract": "In response to a comment on their previous note about the Voigt line profile, here the authors clarify relevant statements and numeric algorithms in the original note.", "date": "2012-01", "date_type": "published", "publication": "Journal of the Atmospheric Sciences", "volume": "69", "number": "1", "publisher": "American Meteorological Society", "pagerange": "414-415", "id_number": "CaltechAUTHORS:20120210-093901822", "issn": "0022-4928", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20120210-093901822", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1175/JAS-D-11-0186.1", "primary_object": { "basename": "Huang2012p17055J_Atmos_Sci.pdf", "url": "https://authors.library.caltech.edu/records/jmr96-9nq34/files/Huang2012p17055J_Atmos_Sci.pdf" }, "resource_type": "article", "pub_year": "2012", "author_list": "Huang, Xianglei and Yung, Yuk Ling" }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/81xfm-dt428", "eprint_id": 52943, "eprint_status": "archive", "datestamp": "2023-08-22 04:31:19", "lastmod": "2024-01-13 16:13:17", "type": "book_section", "metadata_visibility": "show", "creators": { "items": [ { "id": "Deroo-P", "name": { "family": "Deroo", "given": "Pieter" } }, { "id": "Swain-M-R", "name": { "family": "Swain", "given": "Mark" }, "orcid": "0000-0002-0919-4468" }, { "id": "Vasisht-G", "name": { "family": "Vasisht", "given": "Gautam" }, "orcid": "0000-0002-1871-6264" }, { "id": "Chen-Pin", "name": { "family": "Chen", "given": "Pin" } }, { "id": "Tinetti-G", "name": { "family": "Tinetti", "given": "Giovanna" } }, { "id": "Bouwman-J", "name": { "family": "Bouwman", "given": "Jeroen" } }, { "id": "Angerhausen-D", "name": { "family": "Angerhausen", "given": "Daniel" } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk Ling" }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Exoplanet Spectroscopy: The Hubble Case", "ispublished": "unpub", "full_text_status": "public", "note": "\u00a9 2011 Astronomical Society of the Pacific.\n\nPieter Deroo is grateful for NASA Fellowship.\n\nPublished - Yung_2011p63.pdf
", "abstract": "The Hubble Space Telescope has recently emerged as the first telescope\nto detect molecular signatures in an exoplanet via infrared spectroscopy. Molecular\nspectroscopy of exoplanets is demanding and requires an accurate determination and\nremoval of the instrument systematics. Here we report on our effort to extract accurate\nexoplanet spectra from NICMOS spectrophotometry. We developed a standardized\nand highly automated pipeline to remove instrument systematics based on our previous\nresults. We tested the pipeline and find excellent agreement with observation specific\nimplementations. The process of decorrelating instrument parameters from the measured\ntime series is well understood, stable and guarantees reproducible results.", "date": "2012", "date_type": "published", "publisher": "Astronomical Society of the Pacific", "place_of_pub": "San Francisco, CA", "pagerange": "63-66", "id_number": "CaltechAUTHORS:20141217-093958592", "isbn": "978-1-58381-782-7", "book_title": "Molecules in the Atmospheres of Extrasolar Planets", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20141217-093958592", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA Postdoctoral Program" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "contributors": { "items": [ { "id": "Beaulieu-J-P", "name": { "family": "Beaulieu", "given": "J -P." } }, { "id": "Dieters-S", "name": { "family": "Dieters", "given": "Stefan" } }, { "id": "Tinetti-G", "name": { "family": "Tinetti", "given": "Giovanna" } } ] }, "primary_object": { "basename": "Yung_2011p63.pdf", "url": "https://authors.library.caltech.edu/records/81xfm-dt428/files/Yung_2011p63.pdf" }, "resource_type": "book_section", "pub_year": "2012", "author_list": "Deroo, Pieter; Swain, Mark; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/3qcmw-8nj46", "eprint_id": 48792, "eprint_status": "archive", "datestamp": "2023-08-22 04:18:40", "lastmod": "2023-10-17 20:26:14", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Li-Liming", "name": { "family": "Li", "given": "Liming" }, "orcid": "0000-0002-5257-9849" }, { "id": "Jiang-Xun", "name": { "family": "Jiang", "given": "Xun" }, "orcid": "0000-0001-8932-3807" }, { "id": "Chahine-M-T", "name": { "family": "Chahine", "given": "Moustafa T." } }, { "id": "Wang-Jingqiang", "name": { "family": "Wang", "given": "Jingqiang" } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "The Mechanical Energies of the Global Atmosphere in El Ni\u00f1o and La Ni\u00f1a Years", "ispublished": "pub", "full_text_status": "public", "keywords": "Atmospheric circulation, Atmosphere-ocean interaction", "note": "\u00a9 2011 American Meteorological Society.\n\nManuscript received 7 March 2011, in final form 18 July 2011.\n\nWe thank M. Gerstell for helpful comments. This work was partly supported by the Jet Propulsion Laboratory, California Institute of Technology, under contract with the National Aeronautics and Space Administration (NASA). This work is also\nsupported by NASA Outer Planets Research Program.\n\nPublished - jas-d-11-072.1.pdf
", "abstract": "Two meteorological reanalysis datasets are analyzed to determine the mechanical energies of the global atmosphere in the El Ni\u00f1o and La Ni\u00f1a years. The general consistency of the mean energy components between the two datasets reveals ~1%\u20133% increase and ~2%\u20133% decrease in the mean energies in the El Ni\u00f1o years and La Ni\u00f1a years, respectively. These analyses further reveal that the tropospheric temperature responds to the sea surface temperature anomaly with a time lag of two months, which leads to the varying mean atmospheric energies in the El Ni\u00f1o and La Ni\u00f1a years.", "date": "2011-12", "date_type": "published", "publication": "Journal of the Atmospheric Sciences", "volume": "68", "number": "12", "publisher": "American Meteorological Society", "pagerange": "3072-3078", "id_number": "CaltechAUTHORS:20140822-084417430", "issn": "0022-4928", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140822-084417430", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA/JPL/Caltech" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1175/JAS-D-11-072.1", "primary_object": { "basename": "jas-d-11-072.1.pdf", "url": "https://authors.library.caltech.edu/records/3qcmw-8nj46/files/jas-d-11-072.1.pdf" }, "resource_type": "article", "pub_year": "2011", "author_list": "Li, Liming; Jiang, Xun; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/xjsp0-gzy62", "eprint_id": 27805, "eprint_status": "archive", "datestamp": "2023-08-22 04:00:14", "lastmod": "2023-10-24 17:26:24", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Wang-Jingqian", "name": { "family": "Wang", "given": "Jingqian" } }, { "id": "Jiang-Xun", "name": { "family": "Jiang", "given": "Xun" }, "orcid": "0000-0001-8932-3807" }, { "id": "Chahine-M-T", "name": { "family": "Chahine", "given": "Moustafa T." } }, { "id": "Liang-Mao-Chang", "name": { "family": "Liang", "given": "Mao-Chang" }, "orcid": "0000-0002-5294-9344" }, { "id": "Olsen-E-T", "name": { "family": "Olsen", "given": "Edward T." } }, { "id": "Chen-Luke-L", "name": { "family": "Chen", "given": "Luke L." } }, { "id": "Licata-S-J", "name": { "family": "Licata", "given": "Stephen J." } }, { "id": "Pagano-T-S", "name": { "family": "Pagano", "given": "Thomas S." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "The influence of tropospheric biennial oscillation on mid-tropospheric CO_2", "ispublished": "pub", "full_text_status": "public", "keywords": "CO2 variability; monsoon", "note": "\u00a9 2011 American Geophysical Union.\n\nReceived 15 August 2011; accepted 28 September 2011; published 29 October 2011. \n\nWe specially acknowledge Alexander Ruzmaikin, Runlie Shia, Fai Li, and three anonymous reviewers, who gave helpful comments on this research. X. Jiang is supported by JPL grant G99694. Y. L. Yung is supported by JPL grant P765982 to the California Institute of Technology. The Editor thanks three anonymous reviewers for their assistance\nin evaluating this paper.\n\nPublished - Wang2011p16252Geophys_Res_Lett.pdf
", "abstract": "Mid-tropospheric CO_2 retrieved from the Atmospheric Infrared Sounder (AIRS) was used to investigate CO_2 interannual variability over the Indo-Pacific region. A signal with periodicity around two years was found for the AIRS mid-tropospheric CO_2 for the first time, which is related to the Tropospheric Biennial Oscillation (TBO) associated with the strength of the monsoon. During a strong (weak) monsoon year, the Western Walker Circulation is strong (weak), resulting in enhanced (diminished) CO_2 transport from the surface to the mid-troposphere. As a result, there are positive (negative) CO2 anomalies at mid-troposphere over the Indo-Pacific region. We simulated the influence of the TBO on the mid-tropospheric CO_2 over the Indo-Pacific region using the MOZART-2 model, and results were consistent with observations, although we found the TBO signal in the model CO_2 is to be smaller than that in the AIRS observations.", "date": "2011-10-29", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "38", "publisher": "American Geophysical Union", "pagerange": "L20805", "id_number": "CaltechAUTHORS:20111116-105808390", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20111116-105808390", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "JPL", "grant_number": "G99694" }, { "agency": "JPL", "grant_number": "P765982" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2011GL049288", "primary_object": { "basename": "Wang2011p16252Geophys_Res_Lett.pdf", "url": "https://authors.library.caltech.edu/records/xjsp0-gzy62/files/Wang2011p16252Geophys_Res_Lett.pdf" }, "resource_type": "article", "pub_year": "2011", "author_list": "Wang, Jingqian; Jiang, Xun; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/xstav-wwn02", "eprint_id": 48796, "eprint_status": "archive", "datestamp": "2023-08-22 03:52:52", "lastmod": "2023-10-17 20:26:23", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Jiang-Xianan", "name": { "family": "Jiang", "given": "Xianan" } }, { "id": "Waliser-D-E", "name": { "family": "Waliser", "given": "Duane E." } }, { "id": "Olson-W-S", "name": { "family": "Olson", "given": "William S." } }, { "id": "Tao-Wei-Kuo", "name": { "family": "Tao", "given": "Wei-Kuo" } }, { "id": "L'Ecuyer-T-S", "name": { "family": "L'Ecuyer", "given": "Tristan S." } }, { "id": "Li-King-Fai", "name": { "family": "Li", "given": "King-Fai" }, "orcid": "0000-0003-0150-2910" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Shige-Shoichi", "name": { "family": "Shige", "given": "Shoichi" } }, { "id": "Lang-S-E", "name": { "family": "Lang", "given": "Stephen" } }, { "id": "Takayabu-Yukari-N", "name": { "family": "Takayabu", "given": "Yukari N." } } ] }, "title": "Vertical Diabatic Heating Structure of the MJO: Intercomparison between Recent Reanalyses and TRMM Estimates", "ispublished": "pub", "full_text_status": "public", "keywords": "Satellite observations, Madden\u2013Julian oscillation, Diabatic heating, General circulation models", "note": "\u00a9 2011 American Meteorological Society.\n\nManuscript received 23 September 2010, in final form 5 April 2011.\n\nWe thank anonymous reviewers for their constructive comments on an earlier version of this manuscript. Thanks also to Terry Kubar for his comments and editorial assistance. The first author (XJ) acknowledges support by NSF Climate and Large-Scale Dynamics under Award ATM-0934285 and NOAA CPPA program under Award NA09OAR4310191. W. Olson and T. L'Ecuyer acknowledge support by NASA NEWS\nprogram. The Wheeler\u2013Hendon MJO index was downloaded from the Australian BMRC website. We also thank Prof. B. Wang for insightful discussion. Part of this research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration.\n\nPublished - 2011mwr3636.1.pdf
", "abstract": "Capitalizing on recently released reanalysis datasets and diabatic heating estimates based on Tropical Rainfall Measuring Mission (TRMM), the authors have conducted a composite analysis of vertical anomalous heating structures associated with the Madden\u2013Julian oscillation (MJO). Because diabatic heating lies at the heart of prevailing MJO theories, the intention of this effort is to provide new insights into the fundamental physics of the MJO. However, some discrepancies in the composite vertical MJO heating profiles are noted among the datasets, particularly between three reanalyses and three TRMM estimates. A westward tilting with altitude in the vertical heating structure of the MJO is clearly evident during its eastward propagation based on three reanalysis datasets, which is particularly pronounced when the MJO migrates from the equatorial eastern Indian Ocean (EEIO) to the western Pacific (WP). In contrast, this vertical tilt in heating structure is not readily seen in the three TRMM products. Moreover, a transition from a shallow to deep heating structure associated with the MJO is clearly evident in a pressure\u2013time plot over both the EEIO and WP in three reanalysis datasets. Although this vertical heating structure transition is detectable over the WP in two TRMM products, it is weakly defined in another dataset over the WP and in all three TRMM datasets over the EEIO.\n\nThe vertical structures of radiative heating QR associated with the MJO are also analyzed based on TRMM and two reanalysis datasets. A westward vertical tilt in QR is apparent in all these datasets: that is, the low-level QR is largely in phase of convection, whereas QR in the upper troposphere lags the maximum convection. The results also suggest a potentially important role of radiative heating for the MJO, particularly over the Indian Ocean. Caveats in heating estimates based on both the reanalysis datasets and TRMM are briefly discussed.", "date": "2011-10", "date_type": "published", "publication": "Monthly Weather Review", "volume": "139", "number": "10", "publisher": "American Meteorological Society", "pagerange": "3208-3223", "id_number": "CaltechAUTHORS:20140822-084732520", "issn": "0027-0644", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140822-084732520", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "ATM-0934285" }, { "agency": "National Oceanic and Atmospheric Administration (NOAA)", "grant_number": "NA09OAR4310191" }, { "agency": "NASA/JPL/Caltech" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1175/2011MWR3636.1", "primary_object": { "basename": "2011mwr3636.1.pdf", "url": "https://authors.library.caltech.edu/records/xstav-wwn02/files/2011mwr3636.1.pdf" }, "resource_type": "article", "pub_year": "2011", "author_list": "Jiang, Xianan; Waliser, Duane E.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/3we0c-vbg51", "eprint_id": 57610, "eprint_status": "archive", "datestamp": "2023-08-22 03:41:02", "lastmod": "2024-01-13 16:18:19", "type": "book_section", "metadata_visibility": "show", "creators": { "items": [ { "id": "Jiang-Yibo", "name": { "family": "Jiang", "given": "Yibo" }, "orcid": "0000-0001-6711-7260" }, { "id": "Aumann-H-H", "name": { "family": "Aumann", "given": "Hartmut H." }, "orcid": "0000-0002-4311-7546" }, { "id": "Lau-Marie-Wingyee", "name": { "family": "Lau", "given": "Marie Wingyee" }, "orcid": "0000-0001-9755-9406" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Climate Change Sensitivity Evaluation from AIRS and IRIS Measurements", "ispublished": "unpub", "full_text_status": "public", "keywords": "Climate Change; Sensitivity; AIRS; IRIS; Calibration; Ozone; CO2; CH4; Longwave Radiation; Modeling", "note": "\u00a9 2011 SPIE.\n\nThis work was carried out at Caltech's Jet Propulsion Laboratory under contract with NASA.\n\nPublished - Jiang_2011p81531Z.pdf
", "abstract": "Outgoing longwave radiation (OLR) measurements over a long period from satellites provide valuable information for climate change. Due to the different coverage, spectral resolution and instrument sensitivities, the data comparisons between different satellites could be problematic and possible artifacts could be easily introduced. In this paper, we illustrate the method and procedures when we compare different satellite measurements by using the data taken by Infrared Interferometric Spectrometer (IRIS) in 1970 and by Atmospheric Infrared Sounder (AIRS) from 2002 to 2010. We use the spectra between 650 cm^(-1) and 1350 cm^(-1) for nadir view footprints in order to match the AIRS and IRIS measurements. Most of the possible sources of error or biases, which include the errors from spatial coverage, spectral resolution, spectra frequency shift due to the field of view, sea surface temperature uncertainty, clear sky determination, and spectra response function (SRF) symmetry, can be corrected. Using the correct SRF is extremely important when comparing spectra in the high slope spectral regions where possible large artifacts could be introduced.", "date": "2011-09-13", "date_type": "published", "publisher": "Society of Photo-Optical Instrumentation Engineers", "place_of_pub": "Bellingham, WA", "pagerange": "Art. No. 81531Z", "id_number": "CaltechAUTHORS:20150518-132913105", "isbn": "978-0-81948-763-6", "book_title": "Earth Observing Systems XVI", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150518-132913105", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA/JPL/Caltech" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "contributors": { "items": [ { "id": "Butler-James-J", "name": { "family": "Butler", "given": "James J." } }, { "id": "Xiong-Jack", "name": { "family": "Xiong", "given": "Jack" } }, { "id": "Gu-Xingfa", "name": { "family": "Gu", "given": "Xingfa" } } ] }, "doi": "10.1117/12.892817", "primary_object": { "basename": "Jiang_2011p81531Z.pdf", "url": "https://authors.library.caltech.edu/records/3we0c-vbg51/files/Jiang_2011p81531Z.pdf" }, "resource_type": "book_section", "pub_year": "2011", "author_list": "Jiang, Yibo; Aumann, Hartmut H.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/swedk-ndz07", "eprint_id": 48790, "eprint_status": "archive", "datestamp": "2023-08-22 03:38:56", "lastmod": "2023-10-17 20:26:10", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Line-M-R", "name": { "family": "Line", "given": "Michael R." }, "orcid": "0000-0002-2338-476X" }, { "id": "Vasisht-G", "name": { "family": "Vasisht", "given": "Gautam" }, "orcid": "0000-0002-1871-6264" }, { "id": "Chen-Pin", "name": { "family": "Chen", "given": "Pin" } }, { "id": "Angerhausen-D", "name": { "family": "Angerhausen", "given": "D." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Thermochemical and Photochemical Kinetics in Cooler Hydrogen-dominated Extrasolar Planets: A Methane-poor GJ436b?", "ispublished": "pub", "full_text_status": "public", "keywords": "astrochemistry; methods: numerical; planets and satellites: atmospheres; planets and satellites: composition; planets and satellites: individual (GJ436b)", "note": "\u00a9 2011 The American Astronomical Society.\n\nReceived 2011 April 14; accepted 2011 June 3; published 2011 August 10\n\nWe thank Julie Moses, Channon Visscher, Karen Willacy,\nand M. C. Liang for useful chemistry discussions and tips.\nWe also thank Xi Zhang, Heather Knutson, Mimi Gerstell,\nMark Allen, the Yuk Yung Group, and the anonymous referee\nfor reading the paper and providing valuable feedback.\nM. Line is supported by the JPL Graduate Fellowship funded\nby the JPL Research and Technology Development Program.\nP. Chen and G. Vasisht are supported by the JPL Research\n& Technology Development Program, and contributions herein\nwere supported by the Jet Propulsion Laboratory, California Institute\nof Technology, under a contract with the National Aeronautics\nand Space Administration.\n\nPublished - 0004-637X_738_1_32.pdf
Submitted - 1104.3183v2.pdf
", "abstract": "We introduce a thermochemical kinetics and photochemical model. We use high-temperature bidirectional reaction rates for important H, C, O, and N reactions (most importantly for CH_4 to CO interconversion), allowing us to attain thermochemical equilibrium, deep in an atmosphere, purely kinetically. This allows the chemical modeling of an entire atmosphere, from deep-atmosphere thermochemical equilibrium to the photochemically dominated regime. We use our model to explore the atmospheric chemistry of cooler (T_(eff) < 10^3 K) extrasolar giant planets. In particular, we choose to model the nearby hot-Neptune GJ436b, the only planet in this temperature regime for which spectroscopic measurements and estimates of chemical abundances now exist. Recent Spitzer measurements with retrieval have shown that methane is driven strongly out of equilibrium and is deeply depleted on the day side of GJ436b, whereas quenched carbon monoxide is abundant. This is surprising because GJ436b is cooler than many of the heavily irradiated hot Jovians and thermally favorable for CH_4, and thus requires an efficient mechanism for destroying it. We include realistic estimates of ultraviolet flux from the parent dM star GJ436, to bound the direct photolysis and photosensitized depletion of CH_4. While our models indicate fairly rich disequilibrium conditions are likely in cooler exoplanets over a range of planetary metallicities, we are unable to generate the conditions for substantial CH_4 destruction. One possibility is an anomalous source of abundant H atoms between 0.01 and 1 bars (which attack CH_4), but we cannot as yet identify an efficient means to produce these hot atoms.", "date": "2011-09-01", "date_type": "published", "publication": "Astrophysical Journal", "volume": "738", "number": "1", "publisher": "American Astronomical Society", "pagerange": "Art. No. 32", "id_number": "CaltechAUTHORS:20140822-083020182", "issn": "0004-637X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140822-083020182", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "JPL Graduate Fellowship" }, { "agency": "JPL Research and Technology Development Program" }, { "agency": "NASA/JPL/Caltech" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1088/0004-637X/738/1/32", "primary_object": { "basename": "0004-637X_738_1_32.pdf", "url": "https://authors.library.caltech.edu/records/swedk-ndz07/files/0004-637X_738_1_32.pdf" }, "related_objects": [ { "basename": "1104.3183v2.pdf", "url": "https://authors.library.caltech.edu/records/swedk-ndz07/files/1104.3183v2.pdf" } ], "resource_type": "article", "pub_year": "2011", "author_list": "Line, Michael R.; Vasisht, Gautam; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/6a61d-a6n95", "eprint_id": 48812, "eprint_status": "archive", "datestamp": "2023-08-22 03:35:26", "lastmod": "2023-10-17 20:27:06", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Wang-Jingqian", "name": { "family": "Wang", "given": "Jingqian" } }, { "id": "Pawson-Steven", "name": { "family": "Pawson", "given": "Steven" } }, { "id": "Tian-Baijun", "name": { "family": "Tian", "given": "Baijun" } }, { "id": "Liang-Mao-Chang", "name": { "family": "Liang", "given": "Mao-Chang" }, "orcid": "0000-0002-5294-9344" }, { "id": "Shia-Run-Lie", "name": { "family": "Shia", "given": "Run-Lie" }, "orcid": "0000-0003-1911-3120" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Jiang-Xun", "name": { "family": "Jiang", "given": "Xun" }, "orcid": "0000-0001-8932-3807" } ] }, "title": "El Ni\u00f1o\u2013Southern Oscillation in Tropical and Midlatitude Column Ozone", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2011 American Meteorological Society.\n\nManuscript received 25 January 2011, in final form 4 April 2011.\n\nWe thank Bernhard Rappenglueck, Barry Lefer, Mimi Gerstell, and three anonymous reviewers for useful inputs and helpful comments. We thank the World Ozone and Ultraviolet Radiation Data Centre for providing the ozone observation data. Dr. Tian's research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration.\n\nPublished - jas-d-11-045.1.pdf
", "abstract": "The impacts of El Ni\u00f1o\u2013Southern Oscillation (ENSO) on the tropical total column ozone, the tropical tropopause pressure, and the 3.5-yr ozone signal in the midlatitude total column ozone were examined using the Goddard Earth Observing System Chemistry\u2013Climate Model (GEOS CCM). Observed monthly mean sea surface temperature and sea ice between 1951 and 2004 were used as boundary conditions for the model. Since the model includes no solar cycle, quasi-biennial oscillation, or volcanic forcing, the ENSO signal was found to dominate the tropical total column ozone variability. Principal component analysis was applied to the detrended, deseasonalized, and low-pass filtered model outputs. The first mode of model total column ozone captured 63.8% of the total variance. The spatial pattern of this mode was similar to that in Total Ozone Mapping Spectrometer (TOMS) observations. There was also a clear ENSO signal in the tropical tropopause pressure in the GEOS CCM, which is related to the ENSO signal in the total column ozone. The regression coefficient between the model total column ozone and the model tropopause pressure was 0.71 Dobson units (DU) hPa^(\u22121). The GEOS CCM was also used to investigate a possible mechanism for the 3.5-yr signal observed in the midlatitude total column ozone. The 3.5-yr signal in the GEOS CCM column ozone is similar to that in the observations, which suggests that a model with realistic ENSO can reproduce the 3.5-yr signal. Hence, it is likely that the 3.5-yr signal was caused by ENSO.", "date": "2011-09", "date_type": "published", "publication": "Journal of the Atmospheric Sciences", "volume": "68", "number": "9", "publisher": "American Meteorological Society", "pagerange": "1911-1921", "id_number": "CaltechAUTHORS:20140822-111748175", "issn": "0022-4928", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140822-111748175", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA/JPL/Caltech" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1175/JAS-D-11-045.1", "primary_object": { "basename": "jas-d-11-045.1.pdf", "url": "https://authors.library.caltech.edu/records/6a61d-a6n95/files/jas-d-11-045.1.pdf" }, "resource_type": "article", "pub_year": "2011", "author_list": "Wang, Jingqian; Pawson, Steven; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/pydj8-yp283", "eprint_id": 48793, "eprint_status": "archive", "datestamp": "2023-08-22 03:22:25", "lastmod": "2023-10-17 20:26:16", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Bergengren-J-C", "name": { "family": "Bergengren", "given": "Jon C." } }, { "id": "Waliser-D-E", "name": { "family": "Waliser", "given": "Duane E." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Ecological sensitivity: a biospheric view of climate change", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 The Author(s) 2011. This article is published with open access at Springerlink.com. This article is distributed under the terms of the Creative Commons Attribution Noncommercial License which permits any noncommercial use, distribution, and reproduction in any medium, provided the original author(s) and source are credited.\n\nReceived: 29 January 2009; Accepted: 2 July 2010; Published online: 22 July 2011.\n\nThe research described in this paper was carried out at the Jet Propulsion Laboratory, Caltech, under a contract with NASA.\n\nPublished - art_10.1007_s10584-011-0065-1.pdf
", "abstract": "Climate change is often characterized in terms of climate sensitivity, the globally averaged temperature rise associated with a doubling of the atmospheric CO2 (equivalent) concentration. In this study, we develop and apply two new ecological sensitivity metrics, analogs of climate sensitivity, to investigate the potential degree of plant community changes over the next three centuries. We use ten climate simulations from the Intergovernmental Panel on Climate Change Fourth Assessment Report, with climate sensitivities from 2\u20134\u00b0C. The concept of climate sensitivity depends upon the continuous nature of the temperature field across the Earth's surface. For this research, the bridge between climate change and biospheric change predictions is provided by the Equilibrium Vegetation Ecology model (EVE), which simulates a continuous description of the Earth's terrestrial plant communities as a function of climate. The ecosensitivity metrics applied to the results of EVE simulations at the end of the twenty-first century result in 49% of the Earth's land surface area undergoing plant community changes and 37% of the world's terrestrial ecosystems undergoing biome-scale changes. EVE is an equilibrium model, and, although rates of ecological change are not addressed, the resultant ecological sensitivity projections provide an estimate of the degree of species turnover that must occur for ecosystems to be in equilibrium with local climates. Regardless of equilibrium timescales, the new metrics highlight the Earth's degree of ecological sensitivity while identifying ecological \"hotspots\" in the terrestrial biosphere's response to projected climate changes over the next three centuries.", "date": "2011-08", "date_type": "published", "publication": "Climatic Change", "volume": "107", "number": "3-4", "publisher": "Springer", "pagerange": "433-457", "id_number": "CaltechAUTHORS:20140822-084458207", "issn": "0165-0009", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140822-084458207", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA/JPL/Caltech" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1007/s10584-011-0065-1", "primary_object": { "basename": "art_10.1007_s10584-011-0065-1.pdf", "url": "https://authors.library.caltech.edu/records/pydj8-yp283/files/art_10.1007_s10584-011-0065-1.pdf" }, "resource_type": "article", "pub_year": "2011", "author_list": "Bergengren, Jon C.; Waliser, Duane E.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/0bpf1-tf063", "eprint_id": 48794, "eprint_status": "archive", "datestamp": "2023-08-22 03:07:14", "lastmod": "2023-10-17 20:26:19", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Li-Liming", "name": { "family": "Li", "given": "Liming" }, "orcid": "0000-0002-5257-9849" }, { "id": "Jiang-Xun", "name": { "family": "Jiang", "given": "Xun" }, "orcid": "0000-0001-8932-3807" }, { "id": "Chahine-M-T", "name": { "family": "Chahine", "given": "Moustafa T." } }, { "id": "Olsen-E-T", "name": { "family": "Olsen", "given": "Edward T." } }, { "id": "Fetzer-E-J", "name": { "family": "Fetzer", "given": "Eric J." } }, { "id": "Chen-Luke-L", "name": { "family": "Chen", "given": "Luke" } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "The recycling rate of atmospheric moisture over the past two decades (1988\u20132009)", "ispublished": "pub", "full_text_status": "public", "keywords": "precipitation; water vapor; recycling rate; hydrological cycle", "note": "\u00a9 2011 IOP Publishing Ltd. Articles submitted before November 2012 are published under the Creative Commons Attribution-NonCommercial-ShareAlike 3.0 Unported (CC BY-NC-SA 3.0) licence, which requires that permission be sought for commercial reuse. \n\nReceived 11 April 2011; Accepted for publication 21 July 2011;\nPublished 17 August 2011.\n\nWe thank S Newman, N Heavens, R Shia, L Kuai, M Line, X Zhang, and M Gerstell for helpful comments. This work was\npartly supported by the Jet Propulsion Laboratory, California\nInstitute of Technology, under contract with the National\nAeronautics and Space Administration. Precipitation data are\nfrom GPCP V 2.1 and SSM/I. Water vapor data are from\nSSM/I.\n\nPublished - 1748-9326_6_3_034018.pdf
", "abstract": "Numerical models predict that the recycling rate of atmospheric moisture decreases with time at the global scale, in response to global warming. A recent observational study (Wentz et al 2007 Science 317 233\u20135) did not agree with the results from numerical models. Here, we examine the recycling rate by using the latest data sets for precipitation and water vapor, and suggest a consistent view of the global recycling rate of atmospheric moisture between numerical models and observations. Our analyses show that the recycling rate of atmospheric moisture has also decreased over the global oceans during the past two decades. In addition, we find different temporal variations of the recycling rate in different regions when exploring the spatial pattern of the recycling rate. In particular, the recycling rate has increased in the high-precipitation region around the equator (i.e., the intertropical convergence zone) and decreased in the low-precipitation region located either side of the equator over the past two decades. Further exploration suggests that the temporal variation of precipitation is stronger than that of water vapor, which results in the positive trend of the recycling rate in the high-precipitation region and the negative trend of the recycling rate in the low-precipitation region.", "date": "2011-07", "date_type": "published", "publication": "Environmental Research Letters", "volume": "6", "number": "3", "publisher": "IOP Publishing Ltd.", "pagerange": "Art. No. 034018", "id_number": "CaltechAUTHORS:20140822-084607580", "issn": "1748-9326", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140822-084607580", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA/JPL/Caltech" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1088/1748-9326/6/3/034018", "primary_object": { "basename": "1748-9326_6_3_034018.pdf", "url": "https://authors.library.caltech.edu/records/0bpf1-tf063/files/1748-9326_6_3_034018.pdf" }, "resource_type": "article", "pub_year": "2011", "author_list": "Li, Liming; Jiang, Xun; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/1qz59-zjz32", "eprint_id": 22890, "eprint_status": "archive", "datestamp": "2023-08-22 02:05:49", "lastmod": "2023-10-23 17:18:41", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Croteau-P", "name": { "family": "Croteau", "given": "Philip" } }, { "id": "Randazzo-J-B", "name": { "family": "Randazzo", "given": "John B." } }, { "id": "Kostko-O", "name": { "family": "Kostko", "given": "Oleg" } }, { "id": "Ahmed-M", "name": { "family": "Ahmed", "given": "Musahid" } }, { "id": "Liang-Mao-Chang", "name": { "family": "Liang", "given": "Mao-Chang" }, "orcid": "0000-0002-5294-9344" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Boering-K-A", "name": { "family": "Boering", "given": "Kristie A." } } ] }, "title": "Measurements of Isotope Effects in the Photoionization of N_2 and Implications for Titan's Atmosphere", "ispublished": "pub", "full_text_status": "public", "keywords": "astrochemistry; ISM: clouds; molecular processes; planets and satellites: atmospheres; planets and satellites: composition; planets\n and satellites: individual (Titan)", "note": "\u00a9 2011 American Astronomical Society. Received 2010 June 18; accepted 2010 December 28; published 2011 January 28. We gratefully acknowledge support from NASA Planetary\nAtmospheres grant NNX08AE69G to UC Berkeley and a\nDreyfus Teacher-Scholar Award for K.A.B.; from the Director,\nOffice of Energy Research, Office of Basic Energy Sciences,\nChemical Sciences Division of the U.S. Department of Energy\nunder contract no. DE-AC02-05CH11231 for O.K., M.A.,\nand the ALS; from NSC grant 98-2111-M-001-014-MY3 to Academia Sinica for M.-C.L.; and NASA grant NX09AB72G\nto the California Institute of Technology for Y.L.Y.\n\nPublished - Croteau2011p13021Astrophys_J_Lett.pdf
", "abstract": "Isotope effects in the non-dissociative photoionization of molecular nitrogen (N_2 + h\u03bd \u2192 N_2^+ + e^\u2212) may play\na role in determining the relative abundances of isotopic species containing nitrogen in interstellar clouds and\nplanetary atmospheres but have not been previously measured. Measurements of the photoionization efficiency\nspectra of ^(14)N^2, ^(15)N^(14)N, and ^(15)N_2 from 15.5 to 18.9 eV (65.6\u201380.0 nm) using the Advanced Light Source at\nLawrence Berkeley National Laboratory show large differences in peak energies and intensities, with the ratio of the energy-dependent photoionization cross sections, \u03c3(^(14)N_2)/\u03c3 (^(15)N^(14)N), ranging from 0.4 to 3.5. Convolving the cross sections with the solar flux and integrating over the energies measured, the ratios of photoionization rate coefficients are J(^(15)N^(14)N)/J(^(14)N_2) = 1.00 \u00b1 0.02 and J(^(15)N_2)/J(^(14)N_2) = 1.00 \u00b1 0.02, suggesting that isotopic fractionation between N_2 and N_2^+ should be small under such conditions. In contrast, in a one-dimensional model of Titan's atmosphere, isotopic self-shielding of ^(14)N_2 leads to values of J(^(15)N^(14)N)/J(^(14)N_2) as large as ~1.17, larger than under optically thin conditions but still much smaller than values as high as ~29 predicted for N_2 photodissociation. Since modeled photodissociation isotope effects overpredict the HC^(15)N/HC^(14)N ratio in Titan's atmosphere, and since both N atoms and N_2^+ ions may ultimately lead to the formation of HCN, estimates of the potential of including N_2 photoionization to contribute to a more quantitative explanation of ^(15)N/^(14)N for HCN in\nTitan's atmosphere are explored.", "date": "2011-02-20", "date_type": "published", "publication": "Astrophysical Journal Letters", "volume": "728", "number": "2", "publisher": "American Astronomical Society", "pagerange": "Art. No. L32", "id_number": "CaltechAUTHORS:20110315-091124835", "issn": "2041-8205", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20110315-091124835", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA Planetary Athmospheres", "grant_number": "NNX08AE69G" }, { "agency": "Department of Energy (DOE) Office of Energy Research, Office of Basic Energy Sciences, Chemical Sciences Division", "grant_number": "DE-AC02-05CH11231" }, { "agency": "NSC", "grant_number": "98-2111-M-001-014-MY3" }, { "agency": "NASA", "grant_number": "NX09AB72G" }, { "agency": "Dreyfus Teacher-Scholar Award" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1088/2041-8205/728/2/L32", "primary_object": { "basename": "Croteau2011p13021Astrophys_J_Lett.pdf", "url": "https://authors.library.caltech.edu/records/1qz59-zjz32/files/Croteau2011p13021Astrophys_J_Lett.pdf" }, "resource_type": "article", "pub_year": "2011", "author_list": "Croteau, Philip; Randazzo, John B.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/qp6q6-ynq22", "eprint_id": 21622, "eprint_status": "archive", "datestamp": "2023-08-22 01:34:30", "lastmod": "2023-10-21 00:11:26", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Beaulieu-J-P", "name": { "family": "Beaulieu", "given": "J. P." }, "orcid": "0000-0003-0014-3354" }, { "id": "Kipping-D-M", "name": { "family": "Kipping", "given": "D. M." } }, { "id": "Batista-V", "name": { "family": "Batista", "given": "V." }, "orcid": "0000-0002-9782-0333" }, { "id": "Tinetti-G", "name": { "family": "Tinetti", "given": "G." } }, { "id": "Ribas-I", "name": { "family": "Ribas", "given": "I." } }, { "id": "Carey-S-J", "name": { "family": "Carey", "given": "S." }, "orcid": "0000-0002-0221-6871" }, { "id": "Noriega-Crespo-J-A", "name": { "family": "Noriega-Crespo", "given": "J. A." } }, { "id": "Griffith-C-A", "name": { "family": "Griffith", "given": "C. A." } }, { "id": "Campanella-G", "name": { "family": "Campanella", "given": "G." } }, { "id": "Dong-S", "name": { "family": "Dong", "given": "S." } }, { "id": "Tennyson-J", "name": { "family": "Tennyson", "given": "J." } }, { "id": "Barber-R-J", "name": { "family": "Barber", "given": "R. J." } }, { "id": "Deroo-P", "name": { "family": "Deroo", "given": "P." } }, { "id": "Fossey-S-J", "name": { "family": "Fossey", "given": "S. J." } }, { "id": "Liang-D", "name": { "family": "Liang", "given": "D." } }, { "id": "Swain-M-R", "name": { "family": "Swain", "given": "M. R." }, "orcid": "0000-0002-0919-4468" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Y." }, "orcid": "0000-0002-4263-2562" }, { "id": "Allard-N", "name": { "family": "Allard", "given": "N." } } ] }, "title": "Water in the atmosphere of HD 209458b from 3.6\u20138 \u03bcm IRAC photometric observations in primary transit", "ispublished": "pub", "full_text_status": "public", "keywords": "techniques: photometric; occultations; planets and satellites: general; planetary systems", "note": "\u00a9 2010 The Authors. Journal compilation \u00a9 2010 RAS.\nAccepted 2010 February 10. Received 2010 February 3; in original form 2009 September 1.\nArticle first published online: 17 Nov 2010.\n\n\n\nWe are very grateful to Tommi Koskinen, Alan Aylward Steve\nMiller, Jean-Pierre Maillard and Giusi Micela for their insightful comments. GT is supported by a Royal Society University Research Fellowship; DMK by STFC; RJB by the Leverhulme Trust; GC by Ateneo Federato della Scienza e della Tecnologia \u2013 Universit\u00e1 di Roma 'La Sapienza', Collegio univ. 'Don N. Mazza' and LLP-Erasmus Student Placement. We acknowledge the support by ANR-06-BLAN-0416 and the 'Programme Origine des Plan\u00e8tes et de la Vie'. This paper is based on observations made with the Spitzer Space Telescope, which is operated by the Jet Propulsion\nLaboratory, California Institute of Technology under a contract with NASA.\n\nPublished - Beaulieu2010p12288Mon_Not_R_Astron_Soc.pdf
", "abstract": "The hot Jupiter HD 209458b was observed during primary transit at 3.6, 4.5, 5.8 and 8.0 \u03bcm using the Infrared Array Camera (IRAC) on the Spitzer Space Telescope. We describe the procedures we adopted to correct for the systematic effects present in the IRAC data and the subsequent analysis. The light curves were fitted including limb-darkening effects and fitted using Markov Chain Monte Carlo and prayer-bead Monte Carlo techniques, obtaining almost identical results. The final depth measurements obtained by a combined Markov Chain Monte Carlo fit are at 3.6 \u03bcm, 1.469 \u00b1 0.013 and 1.448 \u00b1 0.013 per cent; at 4.5 \u03bcm, 1.478 \u00b1 0.017 per cent; at 5.8 \u03bcm, 1.549 \u00b1 0.015 per cent; and at 8.0 \u03bcm, 1.535 \u00b1 0.011 per cent. Our results clearly indicate the presence of water in the planetary atmosphere. Our broad-band photometric measurements with IRAC prevent us from determining the additional presence of other molecules such as CO, CO_2 and methane for which spectroscopy is needed. While water vapour with a mixing ratio of 10^(-4) to 10^(-3) combined with thermal profiles retrieved from the day side may provide a very good fit to our observations, this data set alone is unable to resolve completely the degeneracy between water abundance and atmospheric thermal profile.", "date": "2010-12-11", "date_type": "published", "publication": "Monthly Notices of the Royal Astronomical Society", "volume": "409", "number": "3", "publisher": "Royal Astronomical Society", "pagerange": "963-974", "id_number": "CaltechAUTHORS:20110106-100201080", "issn": "0035-8711", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20110106-100201080", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Royal Society" }, { "agency": "Science and Technology Facilities Council (STFC)" }, { "agency": "Leverhulme Trust" }, { "agency": "Ateneo Federato della Scienza e della Tecnologia" }, { "agency": "Agence Nationale pour la Recherche (ANR)", "grant_number": "ANR-06-BLAN-0416" } ] }, "local_group": { "items": [ { "id": "Infrared-Processing-and-Analysis-Center-(IPAC)" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1111/j.1365-2966.2010.16516.x", "primary_object": { "basename": "Beaulieu2010p12288Mon_Not_R_Astron_Soc.pdf", "url": "https://authors.library.caltech.edu/records/qp6q6-ynq22/files/Beaulieu2010p12288Mon_Not_R_Astron_Soc.pdf" }, "resource_type": "article", "pub_year": "2010", "author_list": "Beaulieu, J. P.; Kipping, D. M.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/an38b-jwh49", "eprint_id": 21480, "eprint_status": "archive", "datestamp": "2023-08-22 01:27:14", "lastmod": "2023-10-21 00:04:31", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Zhang-Xi", "name": { "family": "Zhang", "given": "Xi" } }, { "id": "Liang-Mao-Chang", "name": { "family": "Liang", "given": "Mao-Chang" }, "orcid": "0000-0002-5294-9344" }, { "id": "Montmessin-F", "name": { "family": "Montmessin", "given": "Franck" } }, { "id": "Bertaux-J-L", "name": { "family": "Bertaux", "given": "Jean-Loup" } }, { "id": "Parkinson-C-D", "name": { "family": "Parkinson", "given": "Christopher D." }, "orcid": "0000-0002-5722-2224" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Photolysis of sulphuric acid as the source of sulphur oxides in the mesosphere of Venus", "ispublished": "pub", "full_text_status": "public", "keywords": "Planetary science", "note": "\u00a9 2010 Macmillan Publishers Limited. \n\nReceived 18 May 2010; Accepted 23 September 2010; Published online 31 October 2010. \n\nWe thank V. Vaida, F. W. Taylor, S. E. Smrekar, F. W. DeMore and O. B. Toon for comments and M. Gerstell, N. Heavens, R. L. Shia and M. Line for reading the manuscipt. This research was supported by NASA grant NNX07AI63G to the California Institute of Technology. M-C.L. was supported by NSC grant 98-2111-M-001-014-MY3 to Academia Sinica. \n\nAuthor Contributions: X.Z., Y.L.Y., C.P. and F.M. contributed to the paper writing. X.Z. carried out the modelling work; M-C.L. helped with the modelling; F.M. and J-L.B. provided the data from the SPICAV instrument on board Venus Express; C.P. provided critical evaluation of the H_2SO_4 photolysis data; Y.L.Y. conceived and supervised the research. \n\nThe authors declare no competing financial interests.\n\nSupplemental Material - ngeo989-s1.pdf
", "abstract": "The sulphur cycle plays fundamental roles in the chemistry and climate of Venus. Thermodynamic equilibrium chemistry at the surface of Venus favours the production of carbonyl sulphide and to a lesser extent sulphur dioxide. These gases are transported to the middle atmosphere by the Hadley circulation cell. Above the cloud top, a sulphur oxidation cycle involves conversion of carbonyl sulphide into sulphur dioxide, which is then transported further upwards. A significant fraction of this sulphur dioxide is subsequently oxidized to sulphur trioxide and eventually reacts with water to form sulphuric acid. Because the vapour pressure of sulphuric acid is low, it readily condenses and forms an upper cloud layer at altitudes of 60\u201370\u2009km, and an upper haze layer above 70\u2009km (ref. 9), which effectively sequesters sulphur oxides from photochemical reactions. Here we present simulations of the fate of sulphuric acid in the Venusian mesosphere based on the Caltech/JPL kinetics model, but including the photolysis of sulphuric acid. Our model suggests that the mixing ratios of sulphur oxides are at least five times higher above 90\u2009km when the photolysis of sulphuric acid is included. Our results are inconsistent with the previous model results but in agreement with the recent observations using ground-based microwave spectroscopy and by Venus Express.", "date": "2010-12", "date_type": "published", "publication": "Nature Geoscience", "volume": "3", "number": "12", "publisher": "Nature Publishing Group", "pagerange": "834-837", "id_number": "CaltechAUTHORS:20101221-104624798", "issn": "1752-0894", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20101221-104624798", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NNX07AI63G" }, { "agency": "National Science Council (Taipei)", "grant_number": "98-2111-M-001-014-MY3" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1038/NGEO989", "primary_object": { "basename": "ngeo989-s1.pdf", "url": "https://authors.library.caltech.edu/records/an38b-jwh49/files/ngeo989-s1.pdf" }, "resource_type": "article", "pub_year": "2010", "author_list": "Zhang, Xi; Liang, Mao-Chang; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/sz73x-4yd12", "eprint_id": 48795, "eprint_status": "archive", "datestamp": "2023-08-22 01:30:54", "lastmod": "2023-10-17 20:26:21", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Tian-Baijun", "name": { "family": "Tian", "given": "Baijun" } }, { "id": "Waliser-D-E", "name": { "family": "Waliser", "given": "Duane E." } }, { "id": "Fetzer-E-J", "name": { "family": "Fetzer", "given": "Eric J." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Vertical Moist Thermodynamic Structure of the Madden\u2013Julian Oscillation in Atmospheric Infrared Sounder Retrievals: An Update and a Comparison to ECMWF Interim Re-Analysis", "ispublished": "pub", "full_text_status": "public", "keywords": "Madden-Julian oscillation, Thermodynamics, Satellite observations, Empirical orthogonal functions, Numerical weather prediction/forecasting", "note": "\u00a9 2010 American Meteorological Society.\n\nManuscript received 4 May 2010, in final form 7 June 2010.\n\nThis research was carried out at JPL/Caltech under a contract with NASA and supported by the AIRS project at JPL and theNSF through Grant ATM-0840755 to UCLA. Comments from M. Wheeler, three anonymous reviewers, and conversations with P. Bauer, M. Goldberg, B. Kahn, E. Manning, E. Olsen, J. Susskind, J. Teixeira, and F. Vitart all helped to improve this paper.\n\nPublished - 2010mwr3486.1.pdf
", "abstract": "The large-scale vertical moist thermodynamic structure of the Madden\u2013Julian oscillation (MJO) was documented using the first 2.5 yr (2002\u201305) of version 4 atmospheric specific humidity and temperature profiles from the Atmospheric Infrared Sounder (AIRS). In this study, this issue is further examined using currently available 7-yr version 5 AIRS data (2002\u201309) to test its dependence on the AIRS data record lengths, AIRS retrieval versions, and MJO event selection and compositing methods employed. The results indicate a strong consistency of the large-scale vertical moist thermodynamic structure of the MJO between different AIRS data record lengths (2.5 vs 7 yr), different AIRS retrieval versions (4 vs 5), and different MJO analysis methods [the extended empirical orthogonal function (EEOF) method vs the multivariate empirical orthogonal function (MEOF) method].\n\nThe large-scale vertical moist thermodynamic structures of the MJO between the AIRS retrievals and the ECMWF Interim Re-Analysis (ERA-Interim) products are also compared. The results indicate a much better agreement of the MJO vertical structure between AIRS and ERA-Interim than with the NCEP\u2013NCAR reanalysis, although a significant difference exists in the magnitude of moisture anomalies between ERA-Interim and AIRS. This characterization of the vertical moist thermodynamic structure of the MJO by AIRS and ERA-Interim offers a useful observation-based metric for general circulation model diagnostics.", "date": "2010-12", "date_type": "published", "publication": "Monthly Weather Review", "volume": "138", "number": "12", "publisher": "American Meteorological Society", "pagerange": "4576-4582", "id_number": "CaltechAUTHORS:20140822-084651782", "issn": "0027-0644", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140822-084651782", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA/JPL/Caltech" }, { "agency": "AIRS Project (JPL)" }, { "agency": "NSF", "grant_number": "ATM-0840755" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1175/2010MWR3486.1", "primary_object": { "basename": "2010mwr3486.1.pdf", "url": "https://authors.library.caltech.edu/records/sz73x-4yd12/files/2010mwr3486.1.pdf" }, "resource_type": "article", "pub_year": "2010", "author_list": "Tian, Baijun; Waliser, Duane E.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/xzax2-63p89", "eprint_id": 21167, "eprint_status": "archive", "datestamp": "2023-08-22 01:20:47", "lastmod": "2023-10-20 23:48:26", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Li-King-Fai", "name": { "family": "Li", "given": "King-Fai" }, "orcid": "0000-0003-0150-2910" }, { "id": "Tian-Baijun", "name": { "family": "Tian", "given": "Baijun" } }, { "id": "Waliser-D-E", "name": { "family": "Waliser", "given": "Duane E." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Tropical mid-tropospheric CO_2 variability driven by the Madden\u2013Julian oscillation", "ispublished": "pub", "full_text_status": "public", "keywords": "convection; intraseasonal variability; remote sensing", "note": "\u00a9 2010 National Academy of Sciences.\n\nEdited by Richard M. Goody, Harvard, Falmouth, MA, and approved September 21, 2010 (received for review June 10, 2010).\nPublished online before print October 26, 2010.\nWe thank Dr. Moustafa T. Chahine, Dr. Edward T. Olsen,\nand Mr. Luke Chen of the AIRS Science Team for providing information on the quality of AIRS data and comments on this work. We also thank Miss Le Kuai, Mr. Michael R. Line, Mr. Da Yang, Dr. Hartmut H. Aumann, Dr. David Crisp, Prof. Andrew P. Ingersoll, Prof. Xun Jiang, Dr. Brian H. Kahn,\nDr. Susan S. Kulawik, Dr. Jack S. Margolis, Dr. Run-Lie Shia, Prof. Ka-Kit Tung, Dr. John R. Worden, and two anonymous reviewers for reviewing the manuscript and providing useful comments. This research was supported\nin part by National Science Foundation (NSF) Grant ATM-0840787 and Grant ATM-0934303 to the California Institute of Technology and NSF Grant ATM-0840755 to University of California, Los Angeles. Y.L.Y. was supported\nby Jet Propulsion Laboratory Grant P765982 to the California Institute of Technology. Part of this research was carried out at the Jet Propulsion Laboratory,\nCalifornia Institute of Technology, under a contract with the National Aeronautics and Space Administration. AIRS Level 3 daily CO2 products were obtained from AIRS Data Server (http://disc.sci.gsfc.nasa.gov/AIRS/dataholdings/\nby-data-product/AIRX3C2D). AIRS Level 3 daily H2O products were obtained from AIRS Data Server (http://disc.sci.gsfc.nasa.gov/AIRS/dataholdings/\nby-data-product/airsL3_STD_AIRS_AMSU.shtml). NCEP/NCAR reanalysis data used in this study were provided by the NOAA/Office of Oceanic and Atmospheric Research (OAR)/ESRL Physical Sciences Division (PSD) Data Server (http://www.esrl.noaa.gov/psd/data/reanalysis/). ERA-interim reanalysis data used in this study were obtained from the ECMWF Data Server\n(http://data.ecmwf.int/data/). The NOAA ESRL CO2 data from the Carbon Cycle Cooperative Global Air Sampling Network, 1968\u20132008, Version 2009- 07-15, were obtained from the NOAA FTP server \n(ftp://ftp.cmdl.noaa.gov/ccg/co2/flask/event/). CONTRAIL data were obtained from theWorld Meteorological\nOrganization World Data Centre for Greenhouse Gases (http://gaw.kishou.go.jp/cgi-bin/wdcgg/accessdata.cgi). RMM indices were obtained from\nhttp://www.cawcr.gov.au/bmrc/clfor/cfstaff/matw/maproom/RMM/.\n\n\nAuthor contributions: K.-F.L., B.T., D.E.W., and Y.L.Y. designed research; K.-F.L. performed research; K.-F.L. analyzed data; and K.-F.L. wrote the paper.\n\nPublished - Li2010p11988P_Natl_Acad_Sci_Usa.pdf
Supplemental Material - pnas.1008222107_SI.pdf
", "abstract": "Carbon dioxide (CO_2) is the most important anthropogenic greenhouse gas in the present-day climate. Most of the community focuses on its long-term (decadal to centennial) behaviors that are relevant to climate change, but there are relatively few discussions of its higher-frequency forms of variability, and none regarding its subseasonal distribution. In this work, we report a large-scale intraseasonal variation in the Atmospheric Infrared Sounder CO_2 data in the global tropical region associated with the Madden\u2013Julian oscillation (MJO). The peak-to-peak amplitude of the composite MJO modulation is ~1 ppmv, with a standard error of the composite mean < 0.1 ppmv. The correlation structure between CO2 and rainfall and vertical velocity indicate positive (negative) anomalies in CO_2 arise due to upward (downward) large-scale vertical motions in the lower troposphere associated with the MJO. These findings can help elucidate how faster processes can organize, transport, and mix CO_2 and provide a robustness test for coupled carbon\u2013climate models.", "date": "2010-11-09", "date_type": "published", "publication": "Proceedings of the National Academy of Sciences of the United States of America", "volume": "107", "number": "45", "publisher": "National Academy of Sciences", "pagerange": "19171-19175", "id_number": "CaltechAUTHORS:20101206-095621099", "issn": "0027-8424", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20101206-095621099", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "ATM-0840787" }, { "agency": "NSF", "grant_number": "ATM-0934303" }, { "agency": "NSF", "grant_number": "ATM-0840755" }, { "agency": "JPL", "grant_number": "P765982" }, { "agency": "NASA" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1073/pnas.1008222107", "pmcid": "PMC2984179", "primary_object": { "basename": "Li2010p11988P_Natl_Acad_Sci_Usa.pdf", "url": "https://authors.library.caltech.edu/records/xzax2-63p89/files/Li2010p11988P_Natl_Acad_Sci_Usa.pdf" }, "related_objects": [ { "basename": "pnas.1008222107_SI.pdf", "url": "https://authors.library.caltech.edu/records/xzax2-63p89/files/pnas.1008222107_SI.pdf" } ], "resource_type": "article", "pub_year": "2010", "author_list": "Li, King-Fai; Tian, Baijun; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/xm0f4-ezy89", "eprint_id": 19396, "eprint_status": "archive", "datestamp": "2023-08-22 00:30:57", "lastmod": "2023-10-20 20:39:08", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Zhou-Li", "name": { "family": "Zhou", "given": "Li" } }, { "id": "Zheng-Weijun", "name": { "family": "Zheng", "given": "Weijun" } }, { "id": "Kaiser-R-I", "name": { "family": "Kaiser", "given": "Ralf I." } }, { "id": "Landera-A", "name": { "family": "Landera", "given": "Alexander" } }, { "id": "Mebel-A-M", "name": { "family": "Mebel", "given": "Alexander M." } }, { "id": "Liang-Mao-Chang", "name": { "family": "Liang", "given": "Mao-Chang" }, "orcid": "0000-0002-5294-9344" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Cosmic-ray-mediated Formation of Benzene on the Surface of Saturn's Moon Titan", "ispublished": "pub", "full_text_status": "public", "keywords": "astrochemistry; comets: general; methods: laboratory; molecular processes; planets and satellites: individual (Titan)", "note": "\u00a9 2010 The American Astronomical Society.\n\nReceived 2009 November 11; accepted 2010 April 11; published 2010 July 14.\n\nThe experimental work was supported by the Chemistry\nDivision of the US National Science Foundation within the\nframework of the Collaborative Research in Chemistry (CRC)\nProgram (NSF-CRC CHE-0627854; LZ, WZ, RIK, AMM).We\nare very much indebted to Matthew R. Hammond and Richard\nN. Zare, Department of Chemistry, Stanford University, Stanford,\nCA, for the LDI measurements. One of us (Y.L.Y.) thanks\nT. Orlando (Georgia Tech) for valuable discussion. Y.L.Y. is\nsupported by NASA grant NASA5-13296 to the California\nInstitute of Technology. M.C.L. is supported by NSC grant 98-\n2111-M-001-014-MY3 to Academia Sinica. We thank Tobias\nOwen (Institute for Astronomy, University of Hawaii) and Roger\nYelle (LPI, Arizona) for stimulating discussions and valuable\ncomments on this manuscript. Special thanks are due to Keran\nO'Brien (Northern Arizona University) for sharing details on\nthe calculations on the cosmic-ray exposure on Titan's surface.\n\nPublished - Zhou2010p10858Astrophys_J.pdf
", "abstract": "The aromatic benzene molecule (C_6H_6)\u2014a central building block of polycyclic aromatic hydrocarbon molecules\u2014is of crucial importance for the understanding of the organic chemistry of Saturn's largest moon, Titan. Here, we show via laboratory experiments and electronic structure calculations that the benzene molecule can be formed on Titan's surface in situ via non-equilibrium chemistry by cosmic-ray processing of low-temperature acetylene (C_2H_2) ices. The actual yield of benzene depends strongly on the surface coverage. We suggest that the cosmic-ray-mediated chemistry on Titan's surface could be the dominant source of benzene, i.e., a factor of at least two orders of magnitude higher compared to previously modeled precipitation rates, in those regions of the surface which have a high surface coverage of acetylene.", "date": "2010-08-01", "date_type": "published", "publication": "Astrophysical Journal", "volume": "718", "number": "2", "publisher": "American Astronomical Society", "pagerange": "1243-1251", "id_number": "CaltechAUTHORS:20100811-112800594", "issn": "0004-637X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20100811-112800594", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF Chemistry Division", "grant_number": "NSF-CRC CHE-0627854" }, { "agency": "NASA", "grant_number": "NASA5-13296" }, { "agency": "NSC", "grant_number": "98-2111-M-001-014-MY3" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1088/0004-637X/718/2/1243", "primary_object": { "basename": "Zhou2010p10858Astrophys_J.pdf", "url": "https://authors.library.caltech.edu/records/xm0f4-ezy89/files/Zhou2010p10858Astrophys_J.pdf" }, "resource_type": "article", "pub_year": "2010", "author_list": "Zhou, Li; Zheng, Weijun; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/vnpv6-31a14", "eprint_id": 19059, "eprint_status": "archive", "datestamp": "2023-08-23 23:30:53", "lastmod": "2023-10-20 19:19:55", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Line-M-R", "name": { "family": "Line", "given": "M. R." }, "orcid": "0000-0002-2338-476X" }, { "id": "Liang-Mao-Chang", "name": { "family": "Liang", "given": "M. C." }, "orcid": "0000-0002-5294-9344" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Y. L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "High-temperature Photochemistry in the Atmosphere of HD 189733b", "ispublished": "pub", "full_text_status": "public", "keywords": "atmospheric effects; methods: numerical; planetary systems; planets and satellites: atmospheres; planets and satellites: individual (HD 189733b); radiative transfer", "note": "\u00a9 2010 The American Astronomical Society. \n\nReceived 2010 April 19; accepted 2010 May 12; published 2010 June 15. \n\nWe especially thank Adam Showman for providing us his\nGCM outputs for temperature and vertical winds, both of which\nform the basis of our model atmosphere, making it possible\nfor us to determine the eddy diffusion coefficient. We also\nthank Run-Li Shia, Giovanna Tinetti, Xi Zhang, Konstantin Batygin, Mimi Gerstell, Chris Parkinson, Vijay Natraj, Kuai\nLe, Mark Swain, Julie Moses, Wes Traub, Pin Chen, Gautam\nVasisht, Nicholas Heavens, Heather Knutson, Sara Seager,\nthe anonymous referee, and the Yuk Yung group for very\nuseful discussions and for reading the manuscript. M.R.L. was supported by the JPL Graduate Fellowship (JPLGF). M.C.L.\nwas supported in part by NSC grant 98-2111-M-001-014-MY3\nto Academia Sinica. Y.L.Y. was supported by NASA grant\nNX09AB72G to the California Institute of Technology.\n\nPublished - Line2010p10603Astrophys_J.pdf
Accepted Version - 1004.4029.pdf
", "abstract": "Recent infrared spectroscopy of hot exoplanets is beginning to reveal their atmospheric composition. Deep within\nthe planetary atmosphere, the composition is controlled by thermochemical equilibrium. Photochemistry becomes\nimportant higher in the atmosphere, at levels above ~1 bar. These two chemistries compete between ~1 and 10 bars\nin hot-Jupiter-like atmospheres, depending on the strength of the eddy mixing and temperature. HD 189733b\nprovides an excellent laboratory in which to study the consequences of chemistry of hot atmospheres. The\nrecent spectra of HD 189733b contain signatures of CH_4, CO_2, CO, and H_2O. Here we identify the primary\nchemical pathways that govern the abundances of CH_4, CO_2, CO, and H_2O in the cases of thermochemical\nequilibrium chemistry, photochemistry, and their combination. Our results suggest that the disequilibrium\nmechanisms can significantly enhance the abundances of these species above their thermochemical equilibrium\nvalue, so some caution must be taken when assuming that an atmosphere is in strict thermochemical equilibrium.", "date": "2010-07-01", "date_type": "published", "publication": "Astrophysical Journal", "volume": "717", "number": "1", "publisher": "American Astronomical Society", "pagerange": "496-502", "id_number": "CaltechAUTHORS:20100715-082042524", "issn": "0004-637X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20100715-082042524", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "JPL Graduate Fellowship" }, { "agency": "National Science Council (Taipei)", "grant_number": "98-2111-M-001-014-MY3" }, { "agency": "NASA", "grant_number": "NX09AB72G" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1088/0004-637X/717/1/496", "primary_object": { "basename": "1004.4029.pdf", "url": "https://authors.library.caltech.edu/records/vnpv6-31a14/files/1004.4029.pdf" }, "related_objects": [ { "basename": "Line2010p10603Astrophys_J.pdf", "url": "https://authors.library.caltech.edu/records/vnpv6-31a14/files/Line2010p10603Astrophys_J.pdf" } ], "resource_type": "article", "pub_year": "2010", "author_list": "Line, M. R.; Liang, M. C.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/zq32m-6f889", "eprint_id": 19130, "eprint_status": "archive", "datestamp": "2023-08-23 23:31:30", "lastmod": "2023-10-20 19:23:46", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Jiang-Xun", "name": { "family": "Jiang", "given": "Xun" }, "orcid": "0000-0001-8932-3807" }, { "id": "Chahine-M-T", "name": { "family": "Chahine", "given": "Moustafa T." } }, { "id": "Olsen-E-T", "name": { "family": "Olsen", "given": "Edward T." } }, { "id": "Chen-Luke-L", "name": { "family": "Chen", "given": "Luke L." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Interannual variability of mid-tropospheric CO_2 from Atmospheric Infrared Sounder", "ispublished": "pub", "full_text_status": "public", "keywords": "mid-tropospheric CO2; large-scale circulation", "note": "\u00a9 2010 American Geophysical Union.\n\nReceived 12 February 2010; revised 10 May 2010; accepted 21 May 2010; published 1 July 2010.\n\nThis work was carried out at the Jet Propulsion\nLaboratory, California Institute of Technology, under contract with\nthe National Aeronautics and Space Administration. X. Jiang is supported\nby JPL grant G99694. We thank two anonymous reviewers for helpful\ncomments.\n\nPublished - Jiang2010p10812Geophys_Res_Lett.pdf
", "abstract": "Atmospheric Infrared Sounder (AIRS) offers a unique opportunity to investigate the variability of mid-tropospheric CO_2 over the entire globe. In this paper, we use AIRS data to examine the interannual variability of CO_2 and find significant correlations between AIRS mid-tropospheric CO_2 and large-scale atmospheric dynamics. During El Ni\u00f1o events, mid-tropospheric CO_2 over the central Pacific Ocean is enhanced whereas it is reduced over the western Pacific Ocean as a result of the change in the Walker circulation. The variation of AIRS CO_2 in the high latitudes of the northern hemisphere is closely related to the strength of the northern hemispheric annular mode. These results contribute to a better understanding of the influence of large-scale dynamics on tracer distributions.", "date": "2010-07-01", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "37", "publisher": "American Geophysical Union", "pagerange": "Art. No. L13801", "id_number": "CaltechAUTHORS:20100720-133357226", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20100720-133357226", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "JPL", "grant_number": "G99694" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2010GL042823", "primary_object": { "basename": "Jiang2010p10812Geophys_Res_Lett.pdf", "url": "https://authors.library.caltech.edu/records/zq32m-6f889/files/Jiang2010p10812Geophys_Res_Lett.pdf" }, "resource_type": "article", "pub_year": "2010", "author_list": "Jiang, Xun; Chahine, Moustafa T.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/55jre-xvp22", "eprint_id": 48810, "eprint_status": "archive", "datestamp": "2023-08-23 23:47:37", "lastmod": "2023-10-17 20:27:03", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Kuai-Le", "name": { "family": "Kuai", "given": "Le" }, "orcid": "0000-0001-6406-1150" }, { "id": "Natraj-V", "name": { "family": "Natraj", "given": "Vijay" }, "orcid": "0000-0003-3154-9429" }, { "id": "Shia-Run-Lie", "name": { "family": "Shia", "given": "Run-Lie" }, "orcid": "0000-0003-1911-3120" }, { "id": "Miller-C-E", "name": { "family": "Miller", "given": "Charles E." }, "orcid": "0000-0002-9380-4838" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Channel selection using information content analysis: A case study of CO_2 retrieval from near infrared measurements", "ispublished": "pub", "full_text_status": "restricted", "keywords": "Retrieval; Channel selection; Information analysis; Carbon dioxide", "note": "\u00a9 2010 Elsevier Ltd. Received 30 October 2009, Revised 21 February 2010, Accepted 22 February 2010, Available online 26 February 2010. Special Issue Dedicated to Laurence S. Rothman on the Occasion of his 70th Birthday. This research is supported by the Orbiting Carbon Observatory (OCO) project, a NASA Earth System Science Pathfinder (ESSP) mission. The authors would like to thank Denis O'Brien, Igor Polonsky and Chris O'Dell from Colorado State University for providing us the orbit simulator code and for helping with its development and maintenance, and James McDuffie from the Jet Propulsion Laboratory (JPL) for providing covariance information.", "abstract": "A major challenge in retrieving CO_2 concentrations from thermal infrared remote sensing comes from the fact that measurements in the 4.3 and 15 \u03bcm absorption bands (AIRS or TES) are sensitive to both temperature and CO_2 variations. This complicates the selection of absorption channels with maximum CO_2 concentration information content. In contrast, retrievals using near infrared (NIR) CO_2 absorption bands are relatively insensitive to temperature and are most sensitive to changes of CO_2 near the surface, where the sources and sinks are located. The Orbiting Carbon Observatory (OCO) was built to measure reflected sunlight in three NIR spectral regions (the 0.76 \u03bcm O_2 A-band and two CO_2 bands at 1.61 and 2.06 \u03bcm). In an effort to significantly increase the speed of accurate CO_2 retrieval algorithms for OCO, we performed an information content analysis to identify the 20 best channels from each CO_2 spectral region to use in OCO retrievals. Retrievals using these 40 channels provide as much as 75% of the total CO_2 information content compared to retrievals using all 1016 channels in each spectral region. The CO_2 retrievals using our selected channels have a precision better than 0.1 ppm. This technique can be applied to the retrieval of other geophysical variables (e.g., temperature or CH_4), or modified for other instruments, such as AIRS or TES.", "date": "2010-06", "date_type": "published", "publication": "Journal of Quantitative Spectroscopy and Radiative Transfer", "volume": "111", "number": "9", "publisher": "Elsevier", "pagerange": "1296-1304", "id_number": "CaltechAUTHORS:20140822-105055535", "issn": "0022-4073", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140822-105055535", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Orbiting Carbon Observatory (OCO)" }, { "agency": "NASA Earth System Science Pathfinder (ESSP) Mission" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/j.jqsrt.2010.02.011", "resource_type": "article", "pub_year": "2010", "author_list": "Kuai, Le; Natraj, Vijay; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/mb3tb-h0y73", "eprint_id": 17808, "eprint_status": "archive", "datestamp": "2023-08-22 00:52:36", "lastmod": "2023-10-20 00:14:52", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Natraj-V", "name": { "family": "Natraj", "given": "Vijay" }, "orcid": "0000-0003-3154-9429" }, { "id": "Shia-Run-Lie", "name": { "family": "Shia", "given": "Run-Lie" }, "orcid": "0000-0003-1911-3120" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "On the use of principal component analysis to speed up radiative transfer calculations", "ispublished": "pub", "full_text_status": "restricted", "keywords": "Fast radiative transfer; Principal component analysis; Two-stream; Remote sensing", "note": "\u00a9 2010 Elsevier Ltd.\n\nReceived 21 July 2009; accepted 3 November 2009. Available online 11 November 2009. \n\nThe research described in this paper was performed for\nthe Orbiting Carbon Observatory Project at the Jet\nPropulsion Laboratory,California Institute ofT echnology,\nunder contracts with the National Aeronautics and\nSpace Administration. This work was supported in\npart by NASA Grant NAG1-1806. The authors would like\nto thank the following people: Denis O'Brien, Igor\nPolonsky, Chris O'Dell and Adam Cardehen for sharing\nthe ECMWF profiles; Hartmut Boesch for computing the\noptical property inputs for the RT calculations; Chris\nO'Dell for the convolution code; Jack Margolis, Mimi\nGerstell and Nima Ghaderi for helpful comments on the\nmanuscript.", "abstract": "Radiative transfer is computationally expensive. However, it is essential to many applications, in particular remote sensing retrievals. Principal component analysis of the optical depth and single scattering albedo profiles has been proposed as a possible method to help ease the computational burden. Here we show how the technique could be applied to a practical problem of CO_2 retrievals from high spectral resolution measurements of reflected sunlight in three near infrared bands. We obtain a speed improvement of more than 50 fold (compared to monochromatic computations), while reproducing the radiances to better than 0.1% accuracy.", "date": "2010-03", "date_type": "published", "publication": "Journal of Quantitative Spectroscopy and Radiative Transfer", "volume": "111", "number": "5", "publisher": "Elsevier", "pagerange": "810-816", "id_number": "CaltechAUTHORS:20100329-105801467", "issn": "0022-4073", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20100329-105801467", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NAG1-1806" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/j.jqsrt.2009.11.004", "resource_type": "article", "pub_year": "2010", "author_list": "Natraj, Vijay; Shia, Run-Lie; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/2xxtz-2pf72", "eprint_id": 48859, "eprint_status": "archive", "datestamp": "2023-08-22 00:51:58", "lastmod": "2023-10-17 20:29:24", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Russell-M-J", "name": { "family": "Russell", "given": "Michael J." } }, { "id": "Parkinson-C-D", "name": { "family": "Parkinson", "given": "Christopher D." }, "orcid": "0000-0002-5722-2224" } ] }, "title": "The Search for Life on Mars", "ispublished": "pub", "full_text_status": "restricted", "keywords": "life, mars, methanogenesis, biochemical vortex, geochemical siphon", "note": "\u00a9 2010 Journal of Cosmology. Posted January 31, 2010. \n\nYLY acknowledge supported by NASA grant NASA5-13296 and the Virtual Planetary Laboratory at the University of Washington. MJR's research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration for Astrobiology : Exobiology and Evolutionary Biology and supported by NASA's Astrobiology Institute (Icy Worlds).\nWe thank N. Heavens, F. Li, X. Zhang, M. Gerstell and M. Line for reading and improving the manuscript.", "abstract": "The abiotic and biological pathways for methanogenesis on Mars are surprisingly similar. Both mechanisms use CO_2 and H_2 as starting materials and result in the production of CH_4. However, the geochemical pathway has a high kinetic barrier and the reaction is slow. A biological pathway quickens this process. The total flux of 1.7x10^7 mol year^(-1) that is needed to maintain the observed CH_4 in steady state in the atmosphere is examined in the context of fluxes of He from the interior of the planet and photochemical production of H_2 in the atmosphere. In situ analysis of the isotopologues of CH_4 and estimates of the relative abundances of members of the alkane family, as well as of CH_4:H_2 ratios and species such as acetic acid, could be used to discriminate between abiotic and biological sources on Mars. Discerning how methane generation emerged on the evolutionarily retarded Mars may open a window on how life originated so long ago on our own planet.", "date": "2010-02", "date_type": "published", "publication": "Journal of Cosmology", "volume": "5", "publisher": "Cosmology Science Publishers", "pagerange": "1121-1130", "id_number": "CaltechAUTHORS:20140825-141003133", "issn": "2159-063X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140825-141003133", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NASA5-13296" }, { "agency": "University of Washington Virtual Planetary Laboratory" }, { "agency": "NASA/JPL/Caltech" }, { "agency": "NASA Astrobiology Institute" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "resource_type": "article", "pub_year": "2010", "author_list": "Yung, Yuk L.; Russell, Michael J.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/acdm9-w3246", "eprint_id": 48791, "eprint_status": "archive", "datestamp": "2023-08-22 00:50:23", "lastmod": "2023-10-17 20:26:12", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Zhang-X", "name": { "family": "Zhang", "given": "X." } }, { "id": "Ajello-J-M", "name": { "family": "Ajello", "given": "J. M." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Y. L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Atomic carbon in the upper atmosphere of Titan", "ispublished": "pub", "full_text_status": "public", "keywords": "planets and satellites: individual (Titan); radiative transfer; scattering", "note": "\u00a9 2010 American Astronomical Society.\n\nReceived 2009 September 28; accepted 2009 November 25; published 2009 December 11.\n\nWe thank M. C. Liang and J. I. Moses for making their\nupdated kinetics for the Titan model available and D. E.\nShemansky for providing the Cassini UVIS stellar occultation\ndata, V. Natraj, M. Line, and M. Gerstell for reading the\nmanuscript. We thank an anonymous referee for providing\nupdates of reaction coefficients. The research was supported\nin part by NASA PATM grant NNX09AB72G to the California\nInstitute of Technology.\n\nPublished - 2041-8205_708_1_L18.pdf
", "abstract": "The atomic carbon emission C I line feature at 1657 \u00c5 (^(3)P^(0)_(J) -^(3)P_J ) in the upper atmosphere of Titan is first identified from the airglow spectra obtained by the Cassini Ultra-violet Imaging Spectrograph. A one-dimensional photochemical model of Titan is used to study the photochemistry of atomic carbon on Titan. Reaction between CH and atomic hydrogen is the major source of atomic carbon, and reactions with hydrocarbons (C_2H_2 and C_2H_4) are the most important loss processes. Resonance scattering of sunlight by atomic carbon is the dominant emission mechanism. The emission intensity calculations based on model results show good agreement with the observations.", "date": "2010-01-01", "date_type": "published", "publication": "Astrophysical Journal Letters", "volume": "708", "number": "1", "publisher": "American Astronomical Society", "pagerange": "L18-L21", "id_number": "CaltechAUTHORS:20140822-083903026", "issn": "2041-8205", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140822-083903026", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NNX09AB72G" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1088/2041-8205/708/1/L18", "primary_object": { "basename": "2041-8205_708_1_L18.pdf", "url": "https://authors.library.caltech.edu/records/acdm9-w3246/files/2041-8205_708_1_L18.pdf" }, "resource_type": "article", "pub_year": "2010", "author_list": "Zhang, X.; Ajello, J. M.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/gp2yv-4qy21", "eprint_id": 16642, "eprint_status": "archive", "datestamp": "2023-08-22 00:49:22", "lastmod": "2023-10-19 22:26:48", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Taketa-Cameron", "name": { "family": "Taketa", "given": "Cameron" } }, { "id": "Cheung-Ross", "name": { "family": "Cheung", "given": "Ross" } }, { "id": "Shia-Run-Lie", "name": { "family": "Shia", "given": "Run-Lie" }, "orcid": "0000-0003-1911-3120" } ] }, "title": "Infinite sum of the product of exponential and logarithmic functions, its analytic continuation, and application", "ispublished": "pub", "full_text_status": "restricted", "keywords": "special function; radiation; exponential integral; series", "note": "\u00a9 AIMS 2009.\n\nReceived: June 2009; revised: September 2009; published: October 2009.\n\nWe thank Vijay Natraj, Tom Apostol, K. K. Tung, Marguerite\nGerstell, Christopher Parkinson, and Tomasz Tyranowski for their valuable\ninputs. Special thanks are due to an anonymous referee of an unnamed journal for\na careful reading of the manuscript and many useful suggestions for improving the\npaper. Cameron Taketa and Ross Cheung acknowledge support by the Summer\nUndergraduate Research Fellowship (SURF) program at the California Institute\nof Technology. One of us (YLY) thanks Professor Richard Goody for the class in\n1972 on atmospheric radiation where he learned the beauty of the mathematics of\nradiative transfer. The research was supported in part by the Orbiting Carbon Observatory Project at the Jet Propulsion Laboratory, and the California Institute\nof Technology.", "abstract": "We show that the function S_(1)(x) = \u2211_(k=1)^\u221e e^(-2\u03c0kx) log k can be expressed as the sum of a simple function and an infinite series, whose coefficients are related to the Riemann zeta function. Analytic continuation to the imaginary argument S_(1)(ix) = K_0(x) is made. For x = p/q where p and q are integers with p < q, closed finite sum expressions for K_0(p/q) and K_1(p/q) are derived. The latter results enable us to evaluate Ramanujan's function \u03c8(x) = \u2211_(k=1)^\u221e [(logk)/k - (log(k+x))/(k+x)] for x = -2/3, -3/4, and -5/6, confirming what Ramanujan claimed but did not explicitly reveal in his Notebooks. The interpretation of a pair of apparently inscrutable divergent series in the notebooks is discussed. They reveal hitherto unsuspected connections between Ramanujan's \u03c8(x), K_0(x), K_1(x), and the classical formulas of Gauss and Kummer for the digamma function", "date": "2010-01", "date_type": "published", "publication": "Discreet and Continuous Dynamical Systems Series B", "volume": "13", "number": "1", "publisher": "American Institute of Mathematical Sciences", "pagerange": "229-248", "id_number": "CaltechAUTHORS:20091110-113936352", "issn": "1531-3492", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20091110-113936352", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Summer Undergraduate Research Fellowship (SURF), Caltech" }, { "agency": "JPL" }, { "agency": "Caltech" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.3934/dcdsb.2010.13.229", "resource_type": "article", "pub_year": "2010", "author_list": "Yung, Yuk L.; Taketa, Cameron; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/qa519-0rw14", "eprint_id": 16949, "eprint_status": "archive", "datestamp": "2023-08-22 00:45:56", "lastmod": "2023-10-19 22:41:06", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Jiang-Xianan", "name": { "family": "Jiang", "given": "Xianan" } }, { "id": "Waliser-D-E", "name": { "family": "Waliser", "given": "Duane E." } }, { "id": "Tian-Baijun", "name": { "family": "Tian", "given": "Baijun" } }, { "id": "Li-Jui-Lin", "name": { "family": "Li", "given": "Jui-Lin" } }, { "id": "Olson-W-S", "name": { "family": "Olson", "given": "William S." } }, { "id": "Tao-W-K", "name": { "family": "Tao", "given": "Wei-Kuo" } }, { "id": "L'Ecuyer-T-S", "name": { "family": "L'Ecuyer", "given": "Tristan S." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Tompkins-A-M", "name": { "family": "Tompkins", "given": "Adrian M." } }, { "id": "Lang-S-E", "name": { "family": "Lang", "given": "Stephen E." } }, { "id": "Grecu-M", "name": { "family": "Grecu", "given": "Mircea" } } ] }, "title": "Vertical Heating Structures Associated with the MJO as Characterized by TRMM Estimates, ECMWF Reanalyses, and Forecasts: A Case Study during 1998/99 Winter", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2009 American Meteorological Society.\nManuscript received 23 January 2009, in final form 6 June 2009.\nWe thank Drs. A. Del Genio and\nX. Fu and anonymous reviewers for their constructive\ncomments on an earlier version of this manuscript. We\nalso thank W. K.-M. Lau and J. Wu for processing\nthe TRMM/CSH Q1 datasets. This research was carried\nout at the Jet Propulsion Laboratory, California Institute\nof Technology, under a contract with NASA. The\nTRMM/TRAIN Q1 2 QR and QR datasets were generated\nwith the support of NASA NEWS research Grants\nNNG06GC99G and NNG06GC46G, respectively.\n\nPublished - Jiang2009p6504J_Climate.pdf
", "abstract": "The Madden\u2013Julian oscillation (MJO) is a fundamental mode of the tropical atmosphere variability that exerts significant influence on global climate and weather systems. Current global circulation models, unfortunately, are incapable of robustly representing this form of variability. Meanwhile, a well-accepted and comprehensive theory for the MJO is still elusive. To help address this challenge, recent emphasis has been placed on characterizing the vertical structures of the MJO. In this study, the authors analyze vertical heating structures by utilizing recently updated heating estimates based on the Tropical Rainfall Measuring Mission (TRMM) from two different latent heating estimates and one radiative heating estimate. Heating structures from two different versions of the European Centre for Medium-Range Weather Forecasts (ECMWF) reanalyses/forecasts are also examined. Because of the limited period of available datasets at the time of this study, the authors focus on the winter season from October 1998 to March 1999.\n\nThe results suggest that diabatic heating associated with the MJO convection in the ECMWF outputs exhibits much stronger amplitude and deeper structures than that in the TRMM estimates over the equatorial eastern Indian Ocean and western Pacific. Further analysis illustrates that this difference might be due to stronger convective and weaker stratiform components in the ECMWF estimates relative to the TRMM estimates, with the latter suggesting a comparable contribution by the stratiform and convective counterparts in contributing to the total rain rate. Based on the TRMM estimates, it is also illustrated that the stratiform fraction of total rain rate varies with the evolution of the MJO. Stratiform rain ratio over the Indian Ocean is found to be 5% above (below) average for the disturbed (suppressed) phase of the MJO. The results are discussed with respect to whether these heating estimates provide enough convergent information to have implications on theories of the MJO and whether they can help validate global weather and climate models.", "date": "2009-11-15", "date_type": "published", "publication": "Journal of Climate", "volume": "22", "number": "22", "publisher": "American Meteorological Society", "pagerange": "6001-6020", "id_number": "CaltechAUTHORS:20091210-141224309", "issn": "0894-8755", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20091210-141224309", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NNG06GC99G" }, { "agency": "NASA", "grant_number": "NNG06GC46G" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1175/2009JCLI3048.1", "primary_object": { "basename": "Jiang2009p6504J_Climate.pdf", "url": "https://authors.library.caltech.edu/records/qa519-0rw14/files/Jiang2009p6504J_Climate.pdf" }, "resource_type": "article", "pub_year": "2009", "author_list": "Jiang, Xianan; Waliser, Duane E.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/0a1rv-jc534", "eprint_id": 16427, "eprint_status": "archive", "datestamp": "2023-08-22 00:43:58", "lastmod": "2023-10-19 22:13:30", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Swain-M-R", "name": { "family": "Swain", "given": "M. R." }, "orcid": "0000-0002-0919-4468" }, { "id": "Tinetti-G", "name": { "family": "Tinetti", "given": "G." } }, { "id": "Vasisht-G", "name": { "family": "Vasisht", "given": "G." }, "orcid": "0000-0002-1871-6264" }, { "id": "Deroo-P", "name": { "family": "Deroo", "given": "P." } }, { "id": "Griffith-C", "name": { "family": "Griffith", "given": "C." } }, { "id": "Bouwman-J", "name": { "family": "Bouwman", "given": "J." } }, { "id": "Chen-Pin", "name": { "family": "Chen", "given": "Pin" } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Y." }, "orcid": "0000-0002-4263-2562" }, { "id": "Burrows-A-S", "name": { "family": "Burrows", "given": "A. S." }, "orcid": "0000-0002-3099-5024" }, { "id": "Brown-L-R", "name": { "family": "Brown", "given": "L. R." } }, { "id": "Matthews-J", "name": { "family": "Matthews", "given": "J." } }, { "id": "Rowe-J-F", "name": { "family": "Rowe", "given": "J. F." }, "orcid": "0000-0002-5904-1865" }, { "id": "Kuschnig-R", "name": { "family": "Kuschnig", "given": "R." } }, { "id": "Angerhausen-D", "name": { "family": "Angerhausen", "given": "D." } } ] }, "title": "Water, Methane, and Carbon Dioxide Present in the Dayside Spectrum of the Exoplanet HD 209458b", "ispublished": "pub", "full_text_status": "public", "keywords": "planetary systems; techniques: spectroscopic", "note": "\u00a9 2009 The American Astronomical Society.\nReceived 2009 April 28; accepted 2009 August 21; published 2009 October 6.\nWe appreciate the Director's Time Award for these observations,\nand we thank Tommy Wiklind, Beth Padillo, and other\nmembers of the Space Telescope Science Institute staff for\nassistance in planning the observations. We also thank Jonathan\nTennyson and Bob Barber for help with the water line list. G.T.\nwas supported by the Royal Society. A portion of the research\ndescribed in this paper was carried out at the Jet Propulsion\nLaboratory, under a contact with the National Aeronautics and\nSpace Administration.\n\nPublished - Swain2009p6144Astrophys_J.pdf
", "abstract": "Using the NICMOS instrument on the Hubble Space Telescope, we have measured the dayside spectrum of HD 209458b between 1.5 and 2.5 \u03bcm. The emergent spectrum is dominated by features due to the presence of methane (CH_4) and water vapor (H_2O), with smaller contributions from carbon dioxide (CO_2). Combining this near-infrared spectrum with existing mid-infrared measurements shows the existence of a temperature inversion and confirms the interpretation of previous photometry measurements. We find a family of plausible solutions for the molecular abundance and detailed temperature profile. Observationally resolving the ambiguity between abundance and temperature requires either (1) improved wavelength coverage or spectral resolution of the dayside emission spectrum or (2) a transmission spectrum where abundance determinations are less sensitive to the temperature structure.", "date": "2009-10-20", "date_type": "published", "publication": "Astrophysical Journal", "volume": "704", "number": "2", "publisher": "American Astronomical Society", "pagerange": "1616-1621", "id_number": "CaltechAUTHORS:20091021-113138246", "issn": "0004-637X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20091021-113138246", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Royal Society" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1088/0004-637X/704/2/1616", "primary_object": { "basename": "Swain2009p6144Astrophys_J.pdf", "url": "https://authors.library.caltech.edu/records/0a1rv-jc534/files/Swain2009p6144Astrophys_J.pdf" }, "resource_type": "article", "pub_year": "2009", "author_list": "Swain, M. R.; Tinetti, G.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/tseda-hvx34", "eprint_id": 16291, "eprint_status": "archive", "datestamp": "2023-08-22 00:41:43", "lastmod": "2023-10-19 22:04:47", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Gu-X", "name": { "family": "Gu", "given": "X." } }, { "id": "Kim-Y-S", "name": { "family": "Kim", "given": "Y. S." } }, { "id": "Kaiser-R-I", "name": { "family": "Kaiser", "given": "R. I." } }, { "id": "Mebel-A-M", "name": { "family": "Mebel", "given": "A. M." } }, { "id": "Liang-Mao-Chang", "name": { "family": "Liang", "given": "M. C." }, "orcid": "0000-0002-5294-9344" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Y. L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Chemical dynamics of triacetylene formation and implications to the synthesis of polyynes in Titan's atmosphere", "ispublished": "pub", "full_text_status": "public", "keywords": "electronic structure calculations; planetary chemistry; crossed molecular beams; photochemical model", "note": "\u00a92009 by the National Academy of Sciences. \n\nEdited by William Klemperer, Harvard University, Cambridge, MA, and approved August 12, 2009 (received for review January 16, 2009). Published online before print September 14, 2009, doi: 10.1073/pnas.0900525106.\n\nWe thank Dr. Eric Wilson (Jet Propulsion Laboratory, Pasadena, CA) for valuable discussions. This work was supported by National Science Foundation Chemistry Division Grant NSF-CRC CHE-0627854. M.C.L. was supported in part by National Science Council Grant 97-2628-M-001-001 (to Academia Sinica). \n\nAuthor contributions: R.I.K. and A.M.M. designed research; X.G., Y.S.K., A.M.M., M.C.L., and Y.L.Y. performed research; and R.I.K. wrote the paper. \n\nThe authors declare no conflict of interest. \n\nThis article is a PNAS Direct Submission. \n\nThis article contains supporting information online at www.pnas.org/cgi/content/full/0900525106/DCSupplemental.\n\nPublished - Gu2009p6015P_Natl_Acad_Sci_Usa.pdf
Supplemental Material - 0900525106SI.pdf
", "abstract": "For the last four decades, the role of polyynes such as diacetylene (HCCCCH) and triacetylene (HCCCCCCH) in the chemical evolution of the atmosphere of Saturn's moon Titan has been a subject of vigorous research. These polyacetylenes are thought to serve as an UV radiation shield in planetary environments; thus, acting as prebiotic ozone, and are considered as important constituents of the visible haze layers on Titan. However, the underlying chemical processes that initiate the formation and control the growth of polyynes have been the least understood to date. Here, we present a combined experimental, theoretical, and modeling study on the synthesis of the polyyne triacetylene (HCCCCCCH) via the bimolecular gas phase reaction of the ethynyl radical (CCH) with diacetylene (HCCCCH). This elementary reaction is rapid, has no entrance barrier, and yields the triacetylene molecule via indirect scattering dynamics through complex formation in a single collision event. Photochemical models of Titan's atmosphere imply that triacetylene may serve as a building block to synthesize even more complex polyynes such as tetraacetylene (HCCCCCCCCH).", "date": "2009-09-22", "date_type": "published", "publication": "Proceedings of the National Academy of Sciences of the United States of America", "volume": "106", "number": "38", "publisher": "National Academy of Sciences", "pagerange": "16078-16083", "id_number": "CaltechAUTHORS:20091013-093447022", "issn": "0027-8424", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20091013-093447022", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "CHE-0627854" }, { "agency": "National Science Council (Taipei)", "grant_number": "97-2628-M-001-001" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1073/pnas.0900525106", "pmcid": "PMC2752517", "primary_object": { "basename": "0900525106SI.pdf", "url": "https://authors.library.caltech.edu/records/tseda-hvx34/files/0900525106SI.pdf" }, "related_objects": [ { "basename": "Gu2009p6015P_Natl_Acad_Sci_Usa.pdf", "url": "https://authors.library.caltech.edu/records/tseda-hvx34/files/Gu2009p6015P_Natl_Acad_Sci_Usa.pdf" } ], "resource_type": "article", "pub_year": "2009", "author_list": "Gu, X.; Kim, Y. S.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/4wp6b-z1136", "eprint_id": 16303, "eprint_status": "archive", "datestamp": "2023-08-22 00:41:36", "lastmod": "2023-10-19 22:05:22", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Keihm-S", "name": { "family": "Keihm", "given": "S." } }, { "id": "Brown-S", "name": { "family": "Brown", "given": "S." } }, { "id": "Teixeira-J", "name": { "family": "Teixeira", "given": "J." } }, { "id": "Desai-S", "name": { "family": "Desai", "given": "S." } }, { "id": "Lu-W", "name": { "family": "Lu", "given": "W." } }, { "id": "Fetzer-E", "name": { "family": "Fetzer", "given": "E." } }, { "id": "Ruf-C", "name": { "family": "Ruf", "given": "C." } }, { "id": "Huang-X", "name": { "family": "Huang", "given": "X." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Y." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Ocean water vapor and cloud liquid water trends from 1992 to 2005 TOPEX Microwave Radiometer data", "ispublished": "pub", "full_text_status": "public", "keywords": "trends", "note": "\u00a92009 American Geophysical Union. \n\nReceived 30 March 2009; accepted 5 June 2009; published 16 September 2009. \n\nThe research described in this paper was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration. Unnamed reviewer comments proved extremely valuable in the production of the published version of this paper.\n\nPublished - Keihm2009p6029J_Geophys_Res-Atmos.pdf
", "abstract": "The continuous 1992\u20132005 data set of the TOPEX Microwave Radiometer (TMR) has been reprocessed to provide global, zonal, and regional scale histories of overocean integrated water vapor (IWV) and cloud liquid water (CLW). Results indicate well-defined trends in IWV on global and hemisphere scales, with values of 1.8 \u00b1 0.4%/decade (60\u00b0S\u201360\u00b0N), 2.4 \u00b1 0.4%/decade (0\u201360\u00b0N), and 1.0 \u00b1 0.5%/decade (0\u201360\u00b0S). The uncertainties represent 1 standard deviation of the regressed slope parameter adjusted for lag 1 autocorrelation. These results are comparable to earlier results based on analyses of the multiinstrument SSM/I ocean measurements beginning in 1988. For the 1992\u20132005 interval, comparisons between SSM/I- and TMR-derived IWV trends show remarkable agreement, with global trends differing by less than 0.3%/decade, comparable to the statistical uncertainty level and about one-sixth of the global TMR-derived trend. Latitudinal and regional analyses of IWV trends show large variability about the global mean, with synoptic scale variations of IWV trends ranging from \u223c\u22128 to +8%/decade. Averaged over 5\u00b0 latitude bands the IWV trends reveal a near zero minimum in the Southern Tropical Pacific and maximum values of \u223c4%/decade over the 30\u201340N latitude band. Comparisons with band latitude averaged SST data over the same 1992\u20132005 interval roughly match a delta_IWV/delta_SST trend scaling of \u223c11%/K, consistent with previously observed tropical and midlatitude seasonal variability. TMR-derived CLW trends are fractionally comparable to the IWV trends. The CLW values are 1.5 \u00b1 0.6%/decade (60\u00b0S\u201360\u00b0N), 2.0 \u00b1 0.8%/decade (0\u201360\u00b0N), and 1.1 \u00b1 0.8%/decade (0\u201360\u00b0S). When scaled to global mean CLW derived from SSM/I and compared seasonally, the TMR CLW variations exhibit excellent tracking with the SSM/I results. Unlike IWV, however, the CLW statistical uncertainties do not likely reflect the dominant error component in the retrieved trends. The 1992\u20132005 CLW trend estimates were particularly sensitive to short-term trends in the first and last 2 years of the TMR archive. Additional errors difficult to quantify include strong aliasing effects from precipitation cells and uncertainties in the radiative transfer models utilized in the generation of the TMR CLW algorithm.", "date": "2009-09-16", "date_type": "published", "publication": "Journal of Geophysical Research D", "volume": "114", "number": "D18", "publisher": "American Geophysical Union", "pagerange": "D18101", "id_number": "CaltechAUTHORS:20091013-093449608", "issn": "0148-0227", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20091013-093449608", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2009JD012145", "primary_object": { "basename": "Keihm2009p6029J_Geophys_Res-Atmos.pdf", "url": "https://authors.library.caltech.edu/records/4wp6b-z1136/files/Keihm2009p6029J_Geophys_Res-Atmos.pdf" }, "resource_type": "article", "pub_year": "2009", "author_list": "Keihm, S.; Brown, S.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/qbq2n-zz281", "eprint_id": 16312, "eprint_status": "archive", "datestamp": "2023-08-22 00:41:24", "lastmod": "2023-10-19 22:05:49", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Hodyss-R-P", "name": { "family": "Hodyss", "given": "Robert" }, "orcid": "0000-0002-6523-3660" }, { "id": "Parkinson-C-D", "name": { "family": "Parkinson", "given": "Christopher D." }, "orcid": "0000-0002-5722-2224" }, { "id": "Johnson-P-V", "name": { "family": "Johnson", "given": "Paul V." } }, { "id": "Stern-J-V", "name": { "family": "Stern", "given": "Julie V." } }, { "id": "Goguen-J-D", "name": { "family": "Goguen", "given": "Jay D." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Kanik-I", "name": { "family": "Kanik", "given": "Isik" } } ] }, "title": "Methanol on Enceladus", "ispublished": "pub", "full_text_status": "public", "keywords": "Enceladus", "note": "\u00a9 2009 American Geophysical Union. \n\nReceived 26 May 2009; accepted 11 August 2009; published 15 September 2009. \n\nThis work was performed at the Jet Propulsion Laboratory (JPL), California Institute of Technology, under a contract with the National Aeronautics and Space Administration (NASA). YLY was supported by NASA grant NNG06GF33G to the California Institute of Technology. Financial support through JPL's Research and Technology Development program is gratefully acknowledged. We thank Bonnie Buratti and James Bauer (JPL) for providing the Cassini VIMS data, and Arthur L. Lane (JPL) for useful discussions.\n\nPublished - Hodyss2009p6039Geophys_Res_Lett.pdf
", "abstract": "Near infrared spectra of the surface of Enceladus returned by Cassini show the presence of an absorption feature at 3.53 \u03bcm, ascribed by Brown et al. (2006) to \"short chain organics,\" and by Newman et al. (2007) to hydrogen peroxide. We assign this feature tentatively to methanol. Variations in the peak position of the feature suggest that methanol in the \"tiger stripes\" region may be segregated from the water ice, and not homogeneously distributed in the ice matrix. The photolytic destruction of methanol implies that methane or methanol itself must be continually deposited on the surface. On Enceladus, methanol may be generated photochemically from a mixed methane/water ice, or deposited from the plume itself. The variation in the concentration of methanol over the surface could be used to distinguish between these two processes.", "date": "2009-09-15", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "36", "number": "17", "publisher": "American Geophysical Union", "pagerange": "L17103", "id_number": "CaltechAUTHORS:20091013-093452305", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20091013-093452305", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NNG06GF33G" }, { "agency": "NASA/JPL/Caltech" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2009GL039336", "primary_object": { "basename": "Hodyss2009p6039Geophys_Res_Lett.pdf", "url": "https://authors.library.caltech.edu/records/qbq2n-zz281/files/Hodyss2009p6039Geophys_Res_Lett.pdf" }, "resource_type": "article", "pub_year": "2009", "author_list": "Hodyss, Robert; Parkinson, Christopher D.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/cq0tk-8tm64", "eprint_id": 16027, "eprint_status": "archive", "datestamp": "2023-08-22 00:41:01", "lastmod": "2023-10-19 21:53:49", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Choi-Yunsoo", "name": { "family": "Choi", "given": "Yunsoo" }, "orcid": "0000-0002-4488-7833" }, { "id": "Kim-Jinwon", "name": { "family": "Kim", "given": "Jinwon" } }, { "id": "Eldering-A", "name": { "family": "Eldering", "given": "Annmarie" }, "orcid": "0000-0003-1080-9922" }, { "id": "Osterman-G-B", "name": { "family": "Osterman", "given": "Gregory" } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Gu-Yu", "name": { "family": "Gu", "given": "Yu" }, "orcid": "0000-0002-3412-0794" }, { "id": "Liou-K-N", "name": { "family": "Liou", "given": "K. N." } } ] }, "title": "Lightning and anthropogenic NO_x sources over the United States and the western North Atlantic Ocean: Impact on OLR and radiative effects", "ispublished": "pub", "full_text_status": "public", "keywords": "OLR, radiative effects, lightning NO_x", "note": "\u00a9 2009 American Geophysical Union. \n\nReceived 30 May 2009; accepted 4 August 2009; published 4 September 2009. \n\nWe thank all members of the OMI, TES and NOAA16 satellite team for providing the data. Special thanks to anonymous reviewers for helpful comments. This work was funded by the Jet Propulsion Laboratory at the California Institute of Technology, under contract to NASA and University of California Office of President, and Grant No. 1700-1737-322-210-13 from the Korean Ministry of Environment.\n\nPublished - Choi2009p5917Geophys_Res_Lett.pdf
", "abstract": "The migration of enhancements in NO_2 concentration, outgoing longwave radiation (OLR), and radiative effects associated with the onset of the North American Monsoon in July 2005 has been investigated using satellite data and the Regional Chemical Transport Model (REAM). The satellite data include the tropospheric NO2 columns, tropospheric O_3 profiles, and OLR from OMI, TES and NOAA-16 satellite, respectively, for June and July 2005. The simulated OLR captures the spatial distribution of the remotely sensed OLR fields with relatively small biases (\u22645.7%) and high spatial correlations (R \u2265 0.88). This study reveals that the lightning-generated NOx exerts a larger, by up to a factor of three, impact on OLR (up to 0.35 Wm^(\u22122)) and radiative effects (up to 0.55 Wm^(\u22122)) by enhancing O_3 in the upper troposphere than anthropogenic NO_x that increases O_3 in the lower troposphere, despite the fact that the lightning-generated NO_x and O_3 are much smaller than those from the anthropogenic emissions. The radiative effect by lightning-derived upper tropospheric O_3 over the convective outflow regions is affected by the changes in lightning frequency. Thus the changes in convection due to global warming may alter the geographical distribution and magnitude of the radiative effect of lightning-derived O3, and this paper is a first step in quantifying the current radiative impact.", "date": "2009-09-04", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "36", "number": "17", "publisher": "American Geophysical Union", "pagerange": "L17806", "id_number": "CaltechAUTHORS:20090923-143136385", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20090923-143136385", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "JPL" }, { "agency": "University of California" }, { "agency": "Ministry of Environment (Korea)", "grant_number": "1700-1737-322-210-13" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2009GL039381", "primary_object": { "basename": "Choi2009p5917Geophys_Res_Lett.pdf", "url": "https://authors.library.caltech.edu/records/cq0tk-8tm64/files/Choi2009p5917Geophys_Res_Lett.pdf" }, "resource_type": "article", "pub_year": "2009", "author_list": "Choi, Yunsoo; Kim, Jinwon; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/s2yag-1pc55", "eprint_id": 15299, "eprint_status": "archive", "datestamp": "2023-08-22 00:39:44", "lastmod": "2023-10-18 21:37:49", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Gu-X", "name": { "family": "Gu", "given": "X." } }, { "id": "Kaiser-R-I", "name": { "family": "Kaiser", "given": "R. I." } }, { "id": "Mebel-A-M", "name": { "family": "Mebel", "given": "A. M." } }, { "id": "Kislov-V-V", "name": { "family": "Kislov", "given": "V. V." } }, { "id": "Klippenstein-S-J", "name": { "family": "Klippenstein", "given": "S. J." } }, { "id": "Harding-L-B", "name": { "family": "Harding", "given": "L. B." } }, { "id": "Liang-Mao-Chang", "name": { "family": "Liang", "given": "M. C." }, "orcid": "0000-0002-5294-9344" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Y. L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "A Crossed Molecular Beams Study on the Formation of the Exotic Cyanoethynyl Radical in Titan's Atmosphere", "ispublished": "pub", "full_text_status": "public", "keywords": "astrochemistry; methods: laboratory; molecular processes; planets and satellites: general; scattering", "note": "\u00a9 2009 American Astronomical Society.\n\nPrint publication: Issue 2 (2009 August 20); received 2009 May 4; accepted for publication 2009 June 3; published 2009 August 6.\n\nThis work was supported by the US National Science\nFoundation \"Collaborative Research in Chemistry Program\"\n(NSF-CRC; CHE-0627854) and by the National Aeronautics\nand Space Administration (08-PATM08-0053 to SJK and\nLBH). We thank Chris Parkinson (University of Michigan) and\nHiroshi Imanaka (University of Arizona) for valuable discussions\nand comments on this manuscript. S.J.K. and L.B.H.\nacknowledge support by the US Department of Energy, Office\nof the Basic Energy Sciences, Division of Chemical\nSciences, Geosciences, and Biosciences under Contract No.\nDE-AC02-06CH11357. Y.L.Y. was supported by NASA grant\nNNG06GF33G to the California Institute of Technology;\nM.C.L. was supported in part by NSC grant 97-2628-M-001-\n001 to Academia Sinica.\n\nPublished - Gu2009p5723Astrophys_J.pdf
", "abstract": "The reaction of the dicarbon molecule (C2) in its ^(1)\u03a3_(g) + electronic ground state with hydrogen cyanide HCN(X^(1)\u03a3^+) is investigated in a crossed molecular beam setup to untangle the formation of the cyanoethynyl radical CCCN(X^(2)\u03a3^+) in hydrocarbon-rich atmospheres of planets and their moons such as Titan. Combined with electronic structure and rate theory calculations, we show that this elementary reaction is rapid, has no entrance barriers, and yields CCCN via successive rearrangements of the initial HC_(3)N collision complex to the cyanoacetylene intermediate (HCCCN) followed by unimolecular decomposition of the latter without exit barrier. New photochemical models imply that this radical could serve as a key building block to form more complex molecules as observed in situ by the Cassini spacecraft, ultimately leading to organic aerosol particles, which make up the orange-brownish haze layers in Titan's atmosphere.", "date": "2009-08-20", "date_type": "published", "publication": "Astrophysical Journal", "volume": "701", "number": "2", "publisher": "American Astronomical Society", "pagerange": "1797-1803", "id_number": "CaltechAUTHORS:20090825-125102819", "issn": "0004-637X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20090825-125102819", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "NSF-CRC" }, { "agency": "NSF", "grant_number": "CHE-0627854" }, { "agency": "NASA", "grant_number": "08-PATM08-0053" }, { "agency": "Deparment of Energy", "grant_number": "DE-AC02-06CH11357" }, { "agency": "NASA", "grant_number": "NNG06GF33G" }, { "agency": "National Science Council (Taiwan)", "grant_number": "97-2628-M-001-001" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1088/0004-637X/701/2/1797", "primary_object": { "basename": "Gu2009p5723Astrophys_J.pdf", "url": "https://authors.library.caltech.edu/records/s2yag-1pc55/files/Gu2009p5723Astrophys_J.pdf" }, "resource_type": "article", "pub_year": "2009", "author_list": "Gu, X.; Kaiser, R. I.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/g7wv5-tsf18", "eprint_id": 15325, "eprint_status": "archive", "datestamp": "2023-08-22 00:38:29", "lastmod": "2023-10-18 21:40:19", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Kuai-Le", "name": { "family": "Kuai", "given": "Le" }, "orcid": "0000-0001-6406-1150" }, { "id": "Shia-Run-Lie", "name": { "family": "Shia", "given": "Run-Lie" }, "orcid": "0000-0003-1911-3120" }, { "id": "Jiang-Xun", "name": { "family": "Jiang", "given": "Xun" }, "orcid": "0000-0001-8932-3807" }, { "id": "Tung-Ka-Kit", "name": { "family": "Tung", "given": "Ka Kit" }, "orcid": "0000-0001-8667-7167" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Modulation of the Period of the Quasi-Biennial Oscillation by the Solar Cycle", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2009 American Meteorological Society. \n\n(Manuscript received 22 September 2008, in final form 23 February 2009) \n\nThis work was supported in part by NASA Grants NAG1-1806 and NNG04GN02G to the California Institute of Technology. K. K. Tung's research was supported by NSF Grants ATM 0332364 and ATM 0808375 to the University of Washington. We thank A. Ruzmaikin and J. Feynman for their useful discussions. We also acknowledge help in improving the paper from M. C. Liang, N. Heavens, X. Guo, A. Soto, T. Lee, X. Zhang, P. S. Jiang, Y. C. Chen, D. Yang, and C. D. Camp.\n\nPublished - Le2009p5703J_Atmos_Sci.pdf
", "abstract": "The authors examine the mechanism of solar cycle modulation of the Quasi-Biennial Oscillation (QBO) period using the Two-and-a-Half-Dimensional Interactive Isentropic Research (THINAIR) model. Previous model results (using 2D and 3D models of varying complexity) have not convincingly established the proposed link of longer QBO periods during solar minima. Observational evidence for such a modulation is also controversial because it is only found during the period from the 1960s to the early 1990s, which is contaminated by volcanic aerosols. In the model, 200- and 400-yr runs without volcano influence can be obtained, long enough to establish some statistical robustness. Both in model and observed data, there is a strong synchronization of the QBO period with integer multiples of the semiannual oscillation (SAO) in the upper stratosphere. Under the current level of wave forcing, the period of the QBO jumps from one multiple of SAO to another and back so that it averages to 28 months, never settling down to a constant period. The \"decadal\" variability in the QBO period takes the form of \"quantum\" jumps; these, however, do not appear to follow the level of the solar flux in either the observation or the model using realistic quasi-periodic solar cycle (SC) forcing. To understand the solar modulation of the QBO period, the authors perform model runs with a range of perpetual solar forcing, either lower or higher than the current level. At the current level of solar forcing, the model QBO period consists of a distribution of four and five SAO periods, similar to the observed distribution. This distribution changes as solar forcing changes. For lower (higher) solar forcing, the distribution shifts to more (less) four SAO periods than five SAO periods. The record-averaged QBO period increases with the solar forcing. However, because this effect is rather weak and is detectable only with exaggerated forcing, the authors suggest that the previous result of the anticorrelation of the QBO period with the SC seen in short observational records reflects only a chance behavior of the QBO period, which naturally jumps in a nonstationary manner even if the solar forcing is held constant, and the correlation can change as the record gets longer.", "date": "2009-08", "date_type": "published", "publication": "Journal of the Atmospheric Sciences", "volume": "66", "number": "8", "publisher": "American Meteorological Society", "pagerange": "2418-2428", "id_number": "CaltechAUTHORS:20090826-112852185", "issn": "0022-4928", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20090826-112852185", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NAG1-1806" }, { "agency": "NASA", "grant_number": "NNG04GN02G" }, { "agency": "NSF", "grant_number": "ATM 0332364" }, { "agency": "NSF", "grant_number": "ATM 0808375" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1175/2009JAS2958.1", "primary_object": { "basename": "Le2009p5703J_Atmos_Sci.pdf", "url": "https://authors.library.caltech.edu/records/g7wv5-tsf18/files/Le2009p5703J_Atmos_Sci.pdf" }, "resource_type": "article", "pub_year": "2009", "author_list": "Kuai, Le; Shia, Run-Lie; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/m4gvs-72t15", "eprint_id": 14976, "eprint_status": "archive", "datestamp": "2023-08-22 00:35:18", "lastmod": "2023-10-18 20:25:15", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Li-King-Fai", "name": { "family": "Li", "given": "King-Fai" }, "orcid": "0000-0003-0150-2910" }, { "id": "Pahlevan-Kaveh", "name": { "family": "Pahlevan", "given": "Kaveh" } }, { "id": "Kirschvink-J-L", "name": { "family": "Kirschvink", "given": "Joseph L." }, "orcid": "0000-0001-9486-6689" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Atmospheric pressure as a natural climate regulator for a terrestrial planet with a biosphere", "ispublished": "pub", "full_text_status": "public", "keywords": "evolution; Gaia; greenhouse; habitability", "note": "\u00a9 2009 by the National Academy of Sciences.\nEdited by Norman H. Sleep, Stanford University, Stanford, CA, and approved April 10, 2009 (received for review September 24, 2008).\nAuthor contributions: K.-F.L., K.P., J.L.K., and Y.L.Y. designed research; K.-F.L. performed\nresearch; K.-F.L. contributed new reagents/analytic tools; K.-F.L. analyzed data; and K.-F.L.,\nK.P., J.L.K., and Y.L.Y. wrote the paper.\nWe thank D. Feldman, V. Natraj, R.-L. Shia, and C.\nParkinson for reading the manuscript. We also thank Prof. Norm Sleep and 2\nanonymous reviewers for their insightful suggestions. K.F.L. and Y.L.Y. were\nsupported by National Aeronautics and Space Administration Grant\nNNG06GF33G and the Virtual Planetary Laboratory at the California Institute\nof Technology.\n\nPublished - Li2009p4619P_Natl_Acad_Sci_Usa.pdf
", "abstract": "Lovelock and Whitfield suggested in 1982 that, as the luminosity of the Sun increases over its life cycle, biologically enhanced silicate weathering is able to reduce the concentration of atmospheric carbon dioxide (CO_2) so that the Earth's surface temperature is maintained within an inhabitable range. As this process continues, however, between 100 and 900 million years (Ma) from now the CO_2 concentration will reach levels too low for C_3 and C_4 photosynthesis, signaling the end of the solar-powered biosphere. Here, we show that atmospheric pressure is another factor that adjusts the global temperature by broadening infrared absorption lines of greenhouse gases. A simple model including the reduction of atmospheric pressure suggests that the life span of the biosphere can be extended at least 2.3 Ga into the future, more than doubling previous estimates. This has important implications for seeking extraterrestrial life in the Universe. Space observations in the infrared region could test the hypothesis that atmospheric pressure regulates the surface temperature on extrasolar planets.", "date": "2009-06-16", "date_type": "published", "publication": "Proceedings of the National Academy of Sciences of the United States of America", "volume": "106", "number": "24", "publisher": "National Academy of Sciences", "pagerange": "9576-9579", "id_number": "CaltechAUTHORS:20090811-154634879", "issn": "0027-8424", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20090811-154634879", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NNG06GF33G" }, { "agency": "Virtual Planetary Laboratory, Caltech" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1073/pnas.0809436106", "pmcid": "PMC2701016", "primary_object": { "basename": "Li2009p4619P_Natl_Acad_Sci_Usa.pdf", "url": "https://authors.library.caltech.edu/records/m4gvs-72t15/files/Li2009p4619P_Natl_Acad_Sci_Usa.pdf" }, "resource_type": "article", "pub_year": "2009", "author_list": "Li, King-Fai; Pahlevan, Kaveh; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/f0ntn-ds759", "eprint_id": 15201, "eprint_status": "archive", "datestamp": "2023-08-22 00:31:56", "lastmod": "2023-10-18 21:04:19", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Kuai-Le", "name": { "family": "Kuai", "given": "Le" }, "orcid": "0000-0001-6406-1150" }, { "id": "Shia-Run-Lie", "name": { "family": "Shia", "given": "Run-Lie" }, "orcid": "0000-0003-1911-3120" }, { "id": "Jiang-Xun", "name": { "family": "Jiang", "given": "Xun" }, "orcid": "0000-0001-8932-3807" }, { "id": "Tung-Ka-Kit", "name": { "family": "Tung", "given": "Ka-Kit" }, "orcid": "0000-0001-8667-7167" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Nonstationary Synchronization of Equatorial QBO with SAO in Observations and a Model", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2009 American Meteorological Society. \n\n(Manuscript received 16 June 2008, in final form 17 November 2008) \n\nThis work was supported in part by NASA Grants NAG1-1806 and NNG04GN02G to the California Institute of Technology. K. K. Tung's research was supported by NSF Grants ATM 0332364 and ATM 0808375 to University of Washington. We thank A. Ruzmaikin and J. Feynman for useful discussions and K. F. Li for his calculation of the solar cycle variation in solar flux data and helpful suggestions. We also acknowledge help in improving the paper from M. C. Liang, N. Heavens, X. Guo, A. Soto, T. Lee, X. Zhang, P. S. Jiang, Y. C. Chen, D. Yang, and C. D. Camp.\n\nPublished - Kuai2009p4733J_Atmos_Sci.pdf
", "abstract": "It has often been suggested that the period of the quasi-biennial oscillation (QBO) has a tendency to synchronize with the semiannual oscillation (SAO). Apparently the synchronization is better the higher up the observation extends. Using 45 yr of the 40-yr European Centre for Medium-Range Weather Forecasts (ECMWF) Re-Analysis (ERA-40) data of the equatorial stratosphere up to the stratopause, the authors confirm that this synchronization is not just a tendency but a robust phenomenon in the upper stratosphere. A QBO period starts when a westerly SAO (w-SAO) descends from the stratopause to 7 hPa and initiates the westerly phase of the QBO (w-QBO) below. It ends when another w-SAO, a few SAO periods later, descends again to 7 hPa to initiate the next w-QBO. The fact that it is the westerly but not the easterly SAO (e-SAO) that initiates the QBO is also explained by the general easterly bias of the angular momentum in the equatorial stratosphere so that the e-SAO does not create a zero-wind line, unlike the w-SAO. The currently observed average QBO period of 28 months, which is not an integer multiple of SAO periods, is a result of intermittent jumps of the QBO period from four SAO to five SAO periods. The same behavior is also found in the Two and a Half Dimensional Interactive Isentropic Research (THINAIR) model. It is found that the nonstationary behavior in both the observation and model is caused not by the 11-yr solar-cycle forcing but by the incompatibility of the QBO's natural period (determined by its wave forcing) and the \"quantized\" period determined by the SAO. The wave forcing parameter for the QBO period in the current climate probably lies between four SAO and five SAO periods. If the wave forcing for the QBO is tuned so that its natural period is compatible with the SAO period above (e.g., at 24 or 30 months), nonstationary behavior disappears.", "date": "2009-06", "date_type": "published", "publication": "Journal of the Atmospheric Sciences", "volume": "66", "number": "6", "publisher": "American Meteorological Society", "pagerange": "1654-1664", "id_number": "CaltechAUTHORS:20090820-162307762", "issn": "0022-4928", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20090820-162307762", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NAG1-1806" }, { "agency": "NASA", "grant_number": "NNG04GN02G" }, { "agency": "NSF", "grant_number": "ATM 0332364" }, { "agency": "NSF", "grant_number": "ATM 0808375" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1175/2008JAS2857.1", "primary_object": { "basename": "Kuai2009p4733J_Atmos_Sci.pdf", "url": "https://authors.library.caltech.edu/records/f0ntn-ds759/files/Kuai2009p4733J_Atmos_Sci.pdf" }, "resource_type": "article", "pub_year": "2009", "author_list": "Kuai, Le; Shia, Run-Lie; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/5rs5k-fqd19", "eprint_id": 14440, "eprint_status": "archive", "datestamp": "2023-08-22 00:29:45", "lastmod": "2023-10-18 17:59:34", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Liang-Mao-Chang", "name": { "family": "Liang", "given": "M. C." }, "orcid": "0000-0002-5294-9344" }, { "id": "Jiang-Xun", "name": { "family": "Jiang", "given": "X." }, "orcid": "0000-0001-8932-3807" }, { "id": "Shia-Run-Lie", "name": { "family": "Shia", "given": "R. L." }, "orcid": "0000-0003-1911-3120" }, { "id": "Lee-C", "name": { "family": "Lee", "given": "C." } }, { "id": "B\u00e9zard-B", "name": { "family": "B\u00e9zard", "given": "B." } }, { "id": "Marcq-E", "name": { "family": "Marcq", "given": "E." } } ] }, "title": "Evidence for carbonyl sulfide (OCS) conversion to CO in the lower atmosphere of Venus", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2009 American Geophysical Union.\nReceived 31 January 2008; revised 30 December 2008; accepted 9 January 2009; published 26 March 2009.\n\nWe thank K. Baines, P. Drossart, J. Moses,\nC. Parkinson, V. Natraj, and X. Zhang for helpful discussions, D. Crisp for\nproviding UV absorber profiles, and K. F. Li, D. Yang, and X. Zhang for\nassistance in preparing the manuscript. Special thanks are due to W. B.\nDeMore for a critical discussion of sulfur chemistry and S. Lebonnois and\nthree anonymous referees for raising fundamental issues the resolution of\nwhich led to a much better paper. This research was supported by NASA\ngrant NNX07AI63G to the California Institute of Technology. M. Liang\nwas supported by NSC 97-2628-M-001-001 grant to Academia Sinica.\n\nPublished - Yung2009p1346J_Geophys_Res-Planet.pdf
", "abstract": "The chemical regimes in the atmosphere of Venus vary from photochemistry in the middle atmosphere to thermal equilibrium chemistry in the lower atmosphere and the surface. Many chemical cycles have been proposed, but few details about these cycles are fully verified by comparison between observations and modeling. Recent high-quality data of carbonyl sulfide (OCS) and CO from ground-based and Venus Express observations provide a unique opportunity to test our understanding of chemistry and transport in the lower atmosphere of Venus. The spatial distributions of OCS and CO in the atmosphere reflect a sensitive balance between chemistry and transport. On the basis of our updated photochemical model and winds from Lee et al.'s (2007) general circulation model, we study the chemistry and transport in a simplified two-dimensional chemistry-transport model. OCS is produced by heterogeneous reactions on the surface; the middle atmosphere is a net sink for OCS. The combination of data and modeling provides strong evidence for the loss of OCS by conversion to CO. The detailed chemical mechanism is currently unknown, although a number of speculations have been proposed. The sensitivity of the distributions of OCS and CO to model parameters is reported.", "date": "2009-03-26", "date_type": "published", "publication": "Journal of Geophysical Research E", "volume": "114", "publisher": "American Geophysical Union", "pagerange": "E00B34", "id_number": "CaltechAUTHORS:20090624-095508559", "issn": "0148-0227", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20090624-095508559", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NNX07AI63G" }, { "agency": "National Science Council (Taiwan)", "grant_number": "97-2628-M-001-001" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2008JE003094", "primary_object": { "basename": "Yung2009p1346J_Geophys_Res-Planet.pdf", "url": "https://authors.library.caltech.edu/records/5rs5k-fqd19/files/Yung2009p1346J_Geophys_Res-Planet.pdf" }, "resource_type": "article", "pub_year": "2009", "author_list": "Yung, Yuk L.; Liang, M. C.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/g3e1k-sj687", "eprint_id": 14461, "eprint_status": "archive", "datestamp": "2023-08-22 00:20:16", "lastmod": "2023-10-18 18:01:09", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Liang-Mao-Chang", "name": { "family": "Liang", "given": "Mao-Chang" }, "orcid": "0000-0002-5294-9344" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Modeling the distribution of H_2O and HDO in the upper atmosphere of Venus", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2009 American Geophysical Union.\n\nReceived 31 January 2008; accepted 2 December 2008; published 24 February 2009. \nSpecial thanks are due to J.-L. Bertaux for providing H_2O, HDO, HCl, and HF profiles from Venus Express. We thank H. Hartman, N. Heavens. K. F. Li, V. Natraj, C. Parkinson, R. L. Shia, and X. Zhang for critical comments. This research was supported in part by NSC grant 97-2628-M-001-001 to Academia Sinica and NASA grant NNX07AI63G to the California Institute of Technology.\n\nPublished - Liang2009p55510.10292008JE003095.pdf
", "abstract": "The chemical and dynamical processes in the upper atmosphere of Venus are poorly known. Recently obtained vertical profiles of trace species from the Venus Express mission, such as HCl, H_2O, and HDO, provide new information to constrain these processes. Here, we simulate these profiles, using the model we have developed and described in a related paper by Yung et al. (2008), with special emphasis on the modeling of H_2O and HDO. A new mechanism, the photo-induced isotopic fractionation effect (PHIFE) of H_2O and HCl, is incorporated into our model. The observed enhancement of HDO could be attributed to (1) preferential destruction of H_2O relative to HDO via PHIFE and (2) escape of hydrogen that enhances the abundance of D and hence its parent molecule HDO. Over a wide range of the sensitivity of the results to the changes of the two mechanisms, we find that the observed profiles of HDO and H2O profiles cannot be explained satisfactorily by current knowledge of chemical and dynamical processes in this region of the atmosphere. Several conjectures to tackle the problems are discussed.", "date": "2009-02-24", "date_type": "published", "publication": "Journal of Geophysical Research E", "volume": "114", "publisher": "American Geophysical Union", "pagerange": "E00B28", "id_number": "CaltechAUTHORS:20090630-105352680", "issn": "0148-0227", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20090630-105352680", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "National Science Council (Taiwan)", "grant_number": "97-2628-M-001-001" }, { "agency": "NASA", "grant_number": "NNX07AI63G" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2008JE003095", "primary_object": { "basename": "Liang2009p55510.10292008JE003095.pdf", "url": "https://authors.library.caltech.edu/records/g3e1k-sj687/files/Liang2009p55510.10292008JE003095.pdf" }, "resource_type": "article", "pub_year": "2009", "author_list": "Liang, Mao-Chang and Yung, Yuk L." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/xp5bc-acm17", "eprint_id": 15356, "eprint_status": "archive", "datestamp": "2023-08-23 23:27:04", "lastmod": "2023-10-18 21:42:37", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Natraj-V", "name": { "family": "Natraj", "given": "Vijay" }, "orcid": "0000-0003-3154-9429" }, { "id": "Li-King-Fai", "name": { "family": "Li", "given": "King-Fai" }, "orcid": "0000-0003-0150-2910" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Rayleigh Scattering in Planetary Atmospheres: Corrected Tables Through Accurate Computation of X and Y Functions", "ispublished": "pub", "full_text_status": "public", "keywords": "polarization; radiative transfer", "note": "\u00a9 2009 The American Astronomical Society.\nReceived 2008 July 7; accepted 2008 October 16; published 2009 February 12.\nThe research described in this paper was performed for\nthe Orbiting Carbon Observatory Project at the Jet Propulsion Laboratory, California Institute of Technology, under a contract\nwith the National Aeronautics and Space Administration. This\nwork was supported in part by NASA grant NAG1\u20131806. The\nauthors thank Professor Tom Hou for helpful discussions on\ntechniques to solve singular integral equations, Run-Lie Shia\nfor the crucial input on the alternative integro-differential form\nof the equations for the X and Y functions, and the reviewer for\ninsightful comments.\n\nPublished - Natraj2009p23510.10880004-637X69121909.pdf
", "abstract": "Tables that have been used as a reference for nearly 50 years for the intensity and polarization of reflected and transmitted light in Rayleigh scattering atmospheres have been found to be inaccurate, even to four decimal places. We convert the integral equations describing the X and Y functions into a pair of coupled integro-differential equations that can be efficiently solved numerically. Special care has been taken in evaluating Cauchy principal value integrals and their derivatives that appear in the solution of the Rayleigh scattering problem. The new approach gives results accurate to eight decimal places for the entire range of tabulation (optical thicknesses 0.02-1.0, surface reflectances 0-0.8, solar and viewing zenith angles 0\u00b0-88.85\u00b0, and relative azimuth angles 0\u00b0-180\u00b0), including the most difficult case of direct transmission in the direction of the sun. Revised tables have been created and stored electronically for easy reference by the planetary science and astrophysics community.", "date": "2009-02-01", "date_type": "published", "publication": "Astrophysical Journal", "volume": "691", "number": "2", "publisher": "American Astronomical Society", "pagerange": "1909-1920", "id_number": "CaltechAUTHORS:20090827-113208371", "issn": "0004-637X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20090827-113208371", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NAG1-1806" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1088/0004-637X/691/2/1909", "primary_object": { "basename": "Q_DN_TAU_0.25", "url": "https://authors.library.caltech.edu/records/xp5bc-acm17/files/Q_DN_TAU_0.25" }, "related_objects": [ { "basename": "Q_UP_TAU_1", "url": 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"https://authors.library.caltech.edu/records/xp5bc-acm17/files/I_DN_TAU_0.25" }, { "basename": "U_DN_TAU_0.1", "url": "https://authors.library.caltech.edu/records/xp5bc-acm17/files/U_DN_TAU_0.1" }, { "basename": "Q_UP_TAU_0.1", "url": "https://authors.library.caltech.edu/records/xp5bc-acm17/files/Q_UP_TAU_0.1" }, { "basename": "Q_UP_TAU_0.15", "url": "https://authors.library.caltech.edu/records/xp5bc-acm17/files/Q_UP_TAU_0.15" }, { "basename": "U_DN_TAU_0.02", "url": "https://authors.library.caltech.edu/records/xp5bc-acm17/files/U_DN_TAU_0.02" }, { "basename": "U_DN_TAU_0.15", "url": "https://authors.library.caltech.edu/records/xp5bc-acm17/files/U_DN_TAU_0.15" }, { "basename": "U_UP_TAU_0.02", "url": "https://authors.library.caltech.edu/records/xp5bc-acm17/files/U_UP_TAU_0.02" }, { "basename": "I_DN_TAU_0.15", "url": "https://authors.library.caltech.edu/records/xp5bc-acm17/files/I_DN_TAU_0.15" }, { "basename": "I_DN_TAU_0.5", "url": "https://authors.library.caltech.edu/records/xp5bc-acm17/files/I_DN_TAU_0.5" }, { "basename": "Q_DN_TAU_0.5", "url": "https://authors.library.caltech.edu/records/xp5bc-acm17/files/Q_DN_TAU_0.5" } ], "resource_type": "article", "pub_year": "2009", "author_list": "Natraj, Vijay; Li, King-Fai; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/sramy-3he35", "eprint_id": 12695, "eprint_status": "archive", "datestamp": "2023-08-22 14:11:42", "lastmod": "2023-10-17 20:26:27", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Swain-M-R", "name": { "family": "Swain", "given": "M. R." }, "orcid": "0000-0002-0919-4468" }, { "id": "Vasisht-G", "name": { "family": "Vasisht", "given": "G." }, "orcid": "0000-0002-1871-6264" }, { "id": "Tinetti-G", "name": { "family": "Tinetti", "given": "G." } }, { "id": "Bouwman-J", "name": { "family": "Bouwman", "given": "J." } }, { "id": "Chen-Pin", "name": { "family": "Chen", "given": "Pin" } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Y." }, "orcid": "0000-0002-4263-2562" }, { "id": "Deming-D", "name": { "family": "Deming", "given": "D." }, "orcid": "0000-0001-5727-4094" }, { "id": "Deroo-P", "name": { "family": "Deroo", "given": "P." } } ] }, "title": "Molecular Signatures in the Near-Infrared Dayside Spectrum of HD 189733b", "ispublished": "pub", "full_text_status": "public", "keywords": "planetary systems; spectroscopic techniques", "note": "\u00a9 2009 The American Astronomical Society. \n\nReceived 2008 September 7, accepted for publication 2008 October 31. Published 2008 December 19. Print publication: Issue 2 (2009 January 10). \n\nWe thank Tommy Wiklind, Nor Prizkal, and other members of the Space Telescope Science Institute staff for extensive assistance in planning the observations and for providing advice about ways in which the observations could be optimized. We also thank Jonathan Fortney for helpful recommendations on improving the presentation of this material. G.T. was supported by the UK Sciences & Technology Facilities Council. A portion of the research described in this paper was carried out at the Jet Propulsion Laboratory, under a contact with the National Aeronautics and Space Administration.\n\nPublished - SWAapjl09.pdf
", "abstract": "We have measured the dayside spectrum of HD 189733b between 1.5 and 2.5 \u03bcm using the NICMOS instrument on the Hubble Space Telescope. The emergent spectrum contains significant modulation, which we attribute to the presence of molecular bands seen in absorption. We find that water (H2O), carbon monoxide (CO), and carbon dioxide (CO2) are needed to explain the observations, and we are able to estimate the mixing ratios for these molecules. We also find temperature decreases with altitude in the ~0.01 < P< ~1 bar region of the dayside near-infrared photosphere and set an upper limit to the dayside abundance of methane (CH4) at these pressures.", "date": "2009-01-10", "date_type": "published", "publication": "Astrophysical Journal Letters", "volume": "690", "number": "2", "publisher": "American Astronomical Society", "pagerange": "L114-L117", "id_number": "CaltechAUTHORS:SWAapjl09", "issn": "2041-8205", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:SWAapjl09", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Science and Technology Facilities Council (STFC)" }, { "agency": "NASA" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1088/0004-637X/690/2/L114", "primary_object": { "basename": "SWAapjl09.pdf", "url": "https://authors.library.caltech.edu/records/sramy-3he35/files/SWAapjl09.pdf" }, "resource_type": "article", "pub_year": "2009", "author_list": "Swain, M. R.; Vasisht, G.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/93fac-5tg18", "eprint_id": 13306, "eprint_status": "archive", "datestamp": "2023-08-22 13:56:37", "lastmod": "2023-10-17 23:23:58", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Jiang-Xun", "name": { "family": "Jiang", "given": "Xun" }, "orcid": "0000-0001-8932-3807" }, { "id": "Li-Qinbin", "name": { "family": "Li", "given": "Qinbin" } }, { "id": "Liang-Mao-Chang", "name": { "family": "Liang", "given": "Mao-Chang" }, "orcid": "0000-0002-5294-9344" }, { "id": "Shia-Run-Lie", "name": { "family": "Shia", "given": "Run-Lie" }, "orcid": "0000-0003-1911-3120" }, { "id": "Chahine-M-T", "name": { "family": "Chahine", "given": "Moustafa T." } }, { "id": "Olsen-E-T", "name": { "family": "Olsen", "given": "Edward T." } }, { "id": "Chen-Luke", "name": { "family": "Chen", "given": "Luke" } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Simulation of upper tropospheric CO\u2082 from chemistry and transport models", "ispublished": "pub", "full_text_status": "public", "keywords": "upper tropospheric CO2; CO2 seasonal cycle; chemistry and transport model", "note": "\u00a9 2008 American Geophysical Union. \n\nReceived 30 June 2007; accepted 21 August 2008; published 30 December 2008. \n\nThis work is performed at JPL under contract with NASA and is supported by project 102438-01.01.01. We thank J. Randerson for useful inputs and helpful comments, two anonymous reviewers, and C.L. Quere for helpful comments. Our special thanks to Bob Yantosca at Harvard University for the help on the GEOS-Chem model and to Peter Hess, Larry Horowitz, and Jean-Francois Lamar on the MOZART-2 model. R.L. Shia and Y.L. Yung are supported by NSF grant ATM-9903790. M.C. Liang also would like to acknowledge the support from an NSC grant 96-2628-M-001-018 to Academia Sinica.\n\nPublished - JIAgbc08.pdf
", "abstract": "The California Institute of Technology/Jet Propulsion Laboratory two-dimensional (2-D), three-dimensional (3-D) GEOS-Chem, and 3-D MOZART-2 chemistry and transport models (CTMs), driven respectively by NCEP2, GEOS-4, and NCEP1 reanalysis data, have been used to simulate upper tropospheric CO2 from 2000 to 2004. Model results of CO2 mixing ratios agree well with monthly mean aircraft observations at altitudes between 8 and 13 km (Matsueda et al., 2002) in the tropics. The upper tropospheric CO2 seasonal cycle phases are well captured by the CTMs. Model results have smaller seasonal cycle amplitudes in the Southern Hemisphere compared with those in the Northern Hemisphere, which are consistent with the aircraft data. Some discrepancies are evident between the model and aircraft data in the midlatitudes, where models tend to underestimate the amplitude of CO2 seasonal cycle. Comparison of the simulated vertical profiles of CO2 between the different models reveals that the convection in the 3-D models is likely too weak in boreal winter and spring. Model sensitivity studies suggest that convection mass flux is important for the correct simulation of upper tropospheric CO2.", "date": "2008-12-30", "date_type": "published", "publication": "Global Biogeochemical Cycles", "volume": "22", "number": "4", "publisher": "American Geophysical Union", "pagerange": "1-11", "id_number": "CaltechAUTHORS:JIAgbc08", "issn": "0886-6236", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:JIAgbc08", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "102438-01.01.01" }, { "agency": "National Science Foundation", "grant_number": "ATM-9903790" }, { "agency": "National Science Council (Taiwan)", "grant_number": "96-2628-M-001-018" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2007GB003049", "primary_object": { "basename": "JIAgbc08.pdf", "url": "https://authors.library.caltech.edu/records/93fac-5tg18/files/JIAgbc08.pdf" }, "resource_type": "article", "pub_year": "2008", "author_list": "Jiang, Xun; Li, Qinbin; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/1ggw1-pg562", "eprint_id": 12946, "eprint_status": "archive", "datestamp": "2023-08-22 13:37:50", "lastmod": "2023-10-17 21:39:53", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Cheung-Ross", "name": { "family": "Cheung", "given": "Ross" } }, { "id": "Li-King-Fai", "name": { "family": "Li", "given": "King-Fai" }, "orcid": "0000-0003-0150-2910" }, { "id": "Wang-Shuhui", "name": { "family": "Wang", "given": "Shuhui" } }, { "id": "Pongetti-T-J", "name": { "family": "Pongetti", "given": "Thomas J." }, "orcid": "0000-0001-9465-0853" }, { "id": "Cagaeo-R-P", "name": { "family": "Cageao", "given": "Richard P." } }, { "id": "Sander-S-P", "name": { "family": "Sander", "given": "Stanley P." }, "orcid": "0000-0003-1424-3620" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Atmospheric hydroxyl radical (OH) abundances from ground-based ultraviolet solar spectra: an improved retrieval method", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2008 Optical Society of America. \n\nReceived 5 November 2007; revised 17 September 2008; accepted 19 September 2008; posted 19 September 2008 (Doc. ID 89379); published 19 November 2008. \n\nWe thank Run-Lie Shia for many valuable discussions on the numerical methods used in this work. We acknowledge the support of the NASA Undergraduate Student Research Program (USRP), the Caltech Summer Undergraduate Research Fellowship (SURF) program, and the NASA Upper Atmosphere Research, Aura Validation, Solar Occultation Satellite Science, and Tropospheric Chemistry Programs. Work at the Jet Propulsion Laboratory, California Institute of Technology, is under contract to the National Aeronautics and Space Administration (NASA).\n\nPublished - CHEao08.pdf
", "abstract": "The Fourier Transform Ultraviolet Spectrometer (FTUVS) instrument has recorded a long-term data record of the atmospheric column abundance of the hydroxyl radical (OH) using the technique of high resolution solar absorption spectroscopy. We report new efforts in improving the precision of the OH measurements in order to better model the diurnal, seasonal, and interannual variability of odd hydrogen (HOx) chemistry in the stratosphere, which, in turn, will improve our understanding of ozone chemistry and its long-term changes. Until the present, the retrieval method has used a single strong OH absorption line P1(1) in the near-ultraviolet at 32,341 cm\u22121. We describe a new method that uses an average based on spectral fits to multiple lines weighted by line strength and fitting precision. We have also made a number of improvements in the ability to fit a model to the spectral feature, which substantially reduces the scatter in the measurements of OH abundances.", "date": "2008-11-20", "date_type": "published", "publication": "Applied Optics", "volume": "47", "number": "33", "publisher": "Optical Society of America", "pagerange": "6277-6284", "id_number": "CaltechAUTHORS:CHEao08", "issn": "0003-6935", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:CHEao08", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA Undergraduate Student Research Program" }, { "agency": "Caltech Summer Undergraduate Research Fellowship (SURF)" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1364/AO.47.006277", "primary_object": { "basename": "CHEao08.pdf", "url": "https://authors.library.caltech.edu/records/1ggw1-pg562/files/CHEao08.pdf" }, "resource_type": "article", "pub_year": "2008", "author_list": "Cheung, Ross; Li, King-Fai; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/xzqbn-53m36", "eprint_id": 12764, "eprint_status": "archive", "datestamp": "2023-08-22 13:37:38", "lastmod": "2023-10-17 20:54:32", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Wang-Shuhui", "name": { "family": "Wang", "given": "Shuhui" } }, { "id": "Pickett-H-M", "name": { "family": "Pickett", "given": "Herbert M." } }, { "id": "Pongetti-T-J", "name": { "family": "Pongetti", "given": "Thomas J." }, "orcid": "0000-0001-9465-0853" }, { "id": "Cheung-Ross", "name": { "family": "Cheung", "given": "Ross" } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Shim-Changsub", "name": { "family": "Shim", "given": "Changsub" } }, { "id": "Li-Qinbi", "name": { "family": "Li", "given": "Qinbi" } }, { "id": "Canty-T", "name": { "family": "Canty", "given": "Timothy" } }, { "id": "Salawitch-R-J", "name": { "family": "Salawitch", "given": "Ross J." } }, { "id": "Jucks-K-W", "name": { "family": "Jucks", "given": "Kenneth W." } }, { "id": "Drouin-B-J", "name": { "family": "Drouin", "given": "Brian" } }, { "id": "Sander-S-P", "name": { "family": "Sander", "given": "Stanley P." }, "orcid": "0000-0003-1424-3620" } ] }, "title": "Validation of Aura Microwave Limb Sounder OH measurements with Fourier Transform Ultra-Violet Spectrometer total OH column measurements at Table Mountain, California", "ispublished": "pub", "full_text_status": "public", "keywords": "OH total column, Aura MLS, FTUVS", "note": "\u00a9 2008. American Geophysical Union. \n\nReceived 29 January 2008; accepted 26 August 2008; published 19 November 2008. \n\nWe acknowledge the support of the NASA Upper Atmosphere Research, Aura Validation, Solar Occultation Satellite Science, and Tropospheric Chemistry Programs, the NASA Undergraduate Student Research Program (USRP) and the Caltech Summer Undergraduate Research Fellowship (SURF) program. We also wish to thank King Fai Li and Run-Lie Shia (Caltech) for helpful discussions. Alyn Lambert (JPL) is kindly acknowledged for helping with the orthogonal linear fit. Work at the Jet Propulsion Laboratory, California Institute of Technology, is under contract to the National Aeronautics and Space Administration.\n\nPublished - WANjgrd08.pdf
", "abstract": "The first seasonal and interannual validation of OH measurements from the Aura Microwave Limb Sounder (MLS) has been conducted using ground-based OH column measurements from the Fourier Transform Ultra-Violet Spectrometer (FTUVS) over the Jet Propulsion Laboratory's Table Mountain Facility (TMF) during 2004\u20132007. To compare with FTUVS total column measurements, MLS OH vertical profiles over TMF are integrated to obtain partial OH columns above 21.5 hPa, which covers nearly 90% of the total column. The tropospheric OH and the lower stratopheric OH not measured by MLS are estimated using GEOS (Goddard Earth Observing System)-Chem and a Harvard 2-D model implemented within GEOS-Chem, respectively. A number of field observations and calculations from a photochemical box model are compared to OH profiles from these models to estimate the variability in the lower atmospheric OH and thus the uncertainty in the combined total OH columns from MLS and models. In general, the combined total OH columns agree extremely well with TMF total OH columns, especially during seasons with high OH. In winter with low OH, the combined columns are often higher than TMF measurements. A slightly weaker seasonal variation is observed by MLS relative to TMF. OH columns from TMF and the combined total columns from MLS and models are highly correlated, resulting in a mean slope of 0.969 with a statistically insignificant intercept. This study therefore suggests that column abundances derived from MLS vertical profiles have been validated to within the mutual systematic uncertainties of the MLS and FTUVS measurements.", "date": "2008-11-19", "date_type": "published", "publication": "Journal of Geophysical Research D", "volume": "113", "publisher": "American Geophysical Union", "pagerange": "D22301", "id_number": "CaltechAUTHORS:WANjgrd08", "issn": "0148-0227", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:WANjgrd08", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA" }, { "agency": "Caltech Summer Undergraduate Research Fellowship (SURF)" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2008JD009883", "primary_object": { "basename": "WANjgrd08.pdf", "url": "https://authors.library.caltech.edu/records/xzqbn-53m36/files/WANjgrd08.pdf" }, "resource_type": "article", "pub_year": "2008", "author_list": "Wang, Shuhui; Pickett, Herbert M.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/bdqk4-djd66", "eprint_id": 12544, "eprint_status": "archive", "datestamp": "2023-08-22 13:34:56", "lastmod": "2023-10-17 17:03:27", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Feldman-D-R", "name": { "family": "Feldman", "given": "D. R." } }, { "id": "L'Ecuyer-T-S", "name": { "family": "L'Ecuyer", "given": "T. S." } }, { "id": "Liou-K-N", "name": { "family": "Liou", "given": "K. N." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Y. L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Remote sensing of tropical tropopause layer radiation balance using A-train measurements", "ispublished": "pub", "full_text_status": "public", "keywords": "CloudSat, TTL, Radiation", "note": "\u00a92008. American Geophysical Union. \n\nReceived 20 March 2008; accepted 8 August 2008; published 12 November 2008. \n\nThis research was supported by the NASA Earth Systems Science Fellowship, grant NNG05GP90H. Invaluable technical support was provided by Tony Clough, Mark Iacono, and Mark Shepard at AER, Inc. The authors would also like to acknowledge the help provided by Jonathan Jiang, Duane Waliser, Brian Kahn, and Frank Li at NASA JPL, Tony Del Genio at NASA GISS, Sally McFarlane of PNNL, Zhiming Kuang of Harvard, and the Yuk Yung Radiation Group including Jack Margolis, Vijay Natraj, Kuai Le, and King-Fai Li. Additionally, the two anonymous reviewers for the paper provided very useful advice. Finally, the CloudSat Data Processing Team provided crucial technical support.\n\nPublished - FELjgrd08b.pdf
", "abstract": "Determining the level of zero net radiative heating (LZH) is critical to understanding parcel trajectory in the Tropical Tropopause Layer (TTL) and associated stratospheric hydration processes. Previous studies of the TTL radiative balance have focused on using radiosonde data, but remote sensing measurements from polar-orbiting satellites may provide the relevant horizontal and vertical information for assessing TTL solar heating and infrared cooling rates, especially across the Pacific Ocean. CloudSat provides a considerable amount of vertical information about the distribution of cloud properties relevant to heating rate analysis. The ability of CloudSat measurements and ancillary information to constrain LZH is explored. We employ formal error propagation analysis for derived heating rate uncertainty given the CloudSat cloud property retrieval algorithms. Estimation of the LZH to within approximately 0.5 to 1 km is achievable with CloudSat, but it has a low-altitude bias because the radar is unable to detect thin cirrus. This can be remedied with the proper utilization of Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations (CALIPSO) lidar backscatter information. By utilizing an orbital simulation with the GISS data set, we explore the representativeness of non-cross-track scanning active sounders in terms of describing the LZH distribution. In order to supplement CloudSat, we explore the ability of Atmospheric Infrared Sounder (AIRS) and Advanced Microwave Scanning Radiometer-EOS (AMSR-E) to constrain LZH and find that these passive sounders are useful where the cloud top height does not exceed 7 km. The spatiotemporal distributions of LZH derived from CloudSat and CALIPSO measurements are presented which suggest that thin cirrus have a limited effect on LZH mean values but affect LZH variability.", "date": "2008-11-12", "date_type": "published", "publication": "Journal of Geophysical Research D", "volume": "113", "number": "D21", "publisher": "American Geophysical Union", "pagerange": "D21113", "id_number": "CaltechAUTHORS:FELjgrd08b", "issn": "0148-0227", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:FELjgrd08b", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NNG05GP90H" } ] }, "collection": "CaltechAUTHORS", "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences", "value": "Division of Geological and Planetary Sciences" } ] }, "doi": "10.1029/2008JD010158", "primary_object": { "basename": "FELjgrd08b.pdf", "url": "https://authors.library.caltech.edu/records/bdqk4-djd66/files/FELjgrd08b.pdf" }, "resource_type": "article", "pub_year": "2008", "author_list": "Feldman, D. R.; L'Ecuyer, T. S.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/bvd86-4j423", "eprint_id": 13525, "eprint_status": "archive", "datestamp": "2023-08-22 13:25:51", "lastmod": "2023-10-17 23:57:58", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Liang-Mao-Chang", "name": { "family": "Liang", "given": "Mao-Chang" }, "orcid": "0000-0002-5294-9344" }, { "id": "Tang-J", "name": { "family": "Tang", "given": "J." } }, { "id": "Chan-Chuen-Yu", "name": { "family": "Chan", "given": "Chuen-Yu" } }, { "id": "Zheng-X-D", "name": { "family": "Zheng", "given": "X. D." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Signature of stratospheric air at the Tibetan Plateau", "ispublished": "pub", "full_text_status": "public", "keywords": "CARBON-DIOXIDE; SURFACE OZONE; ISOTOPIC EXCHANGE; MIDDLE ATMOSPHERE; MONSOON; CO2; TRANSPORT; WALIGUAN; SITES; CHINA", "note": "\u00a9 2008 by the American Geophysical Union.\nReceived 5 July 2008; revised 21 September 2008; accepted 23 September 2008; published 24 October 2008.\nThis work was supported in part by NSC\ngrant 97-2628-M-001-001 to Academia Sinica and the Natural Science\nFoundation of China 40875075. Special thanks are due Matthias Cuntz for\nsharing the biological model results and Shaw Liu for helpful discussion.\nThe measurements of CO_2 and its isotopologues are a cooperative work\nbetween Chinese Academy of Meteorological Sciences and the National\nOceanic and Atmospheric Administration (NOAA). YLY was supported by\nNSF grant ATM-9903790 to California Institute of Technology. Correspondence\nshould be addressed to MCL (e-mail: mcl@rcec.sinica.edu.tw).\n\nPublished - LIAgrl08.pdf
", "abstract": "Current estimates of gross carbon flux tend to ignore the downwelling flux of CO_2 from the stratosphere. Observations showed that there is a phase shift between the time series for the concentration of the standard isotopologue C^16O^16O and C^16O^18O at Waliguan, China (36\u00b017'N, 100\u00b0 54'E, 3816 m) and several other places. Previous attempts to explain the shift have not been satisfactory. Here we show that the phase shift could be explained by the downwelling air from the stratosphere, and demonstrate that this source of CO_2 provides a useful tool for constraining the carbon cycle. Using O_3 as a proxy of stratosphere-troposphere exchange, we find excellent correlation between O_3 and C^16O^18O observed at the Waliguan Observatory. The observed variability of C^16O^18O is consistent with model predictions, thus supporting that the surface air has significant contributions from the stratosphere. Quantitative modeling may provide a powerful tool for constraining the sources and sinks of CO_2 using the isotopically enriched CO_2 from the stratosphere as a tracer.", "date": "2008-10-24", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "35", "number": "20", "publisher": "American Geophysical Union", "pagerange": "L20816", "id_number": "CaltechAUTHORS:LIAgrl08", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:LIAgrl08", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "National Science Council of Taiwan", "grant_number": "97-2628-M-001-001" }, { "agency": "Natural Science Foundation of China", "grant_number": "40875075" }, { "agency": "National Science Foundation", "grant_number": "ATM-9903790" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2008GL035246", "primary_object": { "basename": "LIAgrl08.pdf", "url": "https://authors.library.caltech.edu/records/bvd86-4j423/files/LIAgrl08.pdf" }, "resource_type": "article", "pub_year": "2008", "author_list": "Liang, Mao-Chang; Tang, J.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/rz47c-k6824", "eprint_id": 13381, "eprint_status": "archive", "datestamp": "2023-08-22 13:23:17", "lastmod": "2023-10-17 23:51:18", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Zhou-Li", "name": { "family": "Zhou", "given": "Li" } }, { "id": "Kaiser-R-I", "name": { "family": "Kaiser", "given": "Ralf I." } }, { "id": "Gao-Li-Gyun", "name": { "family": "Gao", "given": "Li Gyun" } }, { "id": "Chang-A-H-H", "name": { "family": "Chang", "given": "Agnes H. H." } }, { "id": "Liang-Mao-Chang", "name": { "family": "Liang", "given": "Mao-Chang" }, "orcid": "0000-0002-5294-9344" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Pathways to oxygen-bearing molecules in the interstellar medium and in planetary atmospheres: Cyclopropenone (c-C_3H_2O) and propynal (HCCCHO)", "ispublished": "pub", "full_text_status": "public", "keywords": "astrobiology; astrochemistry; ISM: molecules; planets and satellites: individual (Titan)", "note": "\u00a9 2008 The American Astronomical Society.\nReceived 2008 February 20; accepted 2008 June 10.\nThe experimental work was supported by the Chemistry division\nof the US National Science Foundation (NSF-CRC CHE-\n0627854). L. G. G. and A. H. H. C. wish to thank the National\nCenter for High Performance Computer of Taiwan for the support\nof computer resources. M. C. L. was supported by an NSC\ngrant to Academia Sinica and by grant NSC 97-2628-M-001-\n001. Y. L. Y. was supported by NASA grant NNX07AI63G to\nthe California Institute of Technology.\n\nPublished - ZHOapj08.pdf
", "abstract": "We investigated the formation of two C_3H_2O isomers, i.e., cyclopropenone (c-C_3H_2O) and propynal (HCCCHO), in binary ice mixtures of carbon monoxide (CO) and acetylene (C_2H_2) at 10 K in an ultrahigh vacuum machine on high-energy electron irradiation. The chemical evolution of the ice samples was followed online and in situ via a Fourier transform infrared spectrometer and a quadrupole mass spectrometer. The temporal profiles of the cyclopropenone and propynal isomers suggest (pseudo-) first-order kinetics. The cyclic structure (c-C_3H_2O) is formed via an addition of triplet carbon monoxide to ground-state acetylene (or vice versa); propynal (HCCCHO) can be synthesized from a carbon monoxide-acetylene complex via a [HCO center dot center dot center dot CCH] radical pair inside the matrix cage. These laboratory studies showed for the first time that both C_3H_2O isomers can be formed in low-temperature ices via nonequilibrium chemistry initiated by energetic electrons as formed in the track of Galactic cosmic ray particles penetrating interstellar icy grains in cold molecular clouds. Our results can explain the hitherto unresolved gas phase abundances of cyclopropenone in star-forming regions via sublimation of c-C_3H_2O as formed on icy grains in the cold molecular cloud stage. Implications for the heterogeneous oxygen chemistry of Titan and icy terrestrial planets and satellites suggest that the production of oxygen-bearing molecules such as C_3H_2O may dominate on aerosol particles compared to pure gas phase chemistry.", "date": "2008-10-20", "date_type": "published", "publication": "Astrophysical Journal", "volume": "686", "number": "2", "publisher": "Astrophysical Journal", "pagerange": "1493-1502", "id_number": "CaltechAUTHORS:ZHOapj08", "issn": "0004-637X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:ZHOapj08", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "NSF-CRC CHE-0627854" }, { "agency": "National Science Center", "grant_number": "NSC 97-2628-M-001001" }, { "agency": "NASA", "grant_number": "NNX07AI63G" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1086/591072", "primary_object": { "basename": "ZHOapj08.pdf", "url": "https://authors.library.caltech.edu/records/rz47c-k6824/files/ZHOapj08.pdf" }, "resource_type": "article", "pub_year": "2008", "author_list": "Zhou, Li; Kaiser, Ralf I.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/x10ks-t0b47", "eprint_id": 13640, "eprint_status": "archive", "datestamp": "2023-08-22 13:13:48", "lastmod": "2023-10-18 00:03:01", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Meadows-V-S", "name": { "family": "Meadows", "given": "Victoria S." } }, { "id": "Orton-G-S", "name": { "family": "Orton", "given": "Glenn" }, "orcid": "0000-0001-7871-2823" }, { "id": "Line-M-R", "name": { "family": "Line", "given": "Michael" }, "orcid": "0000-0002-2338-476X" }, { "id": "Liang-Mao-Chang", "name": { "family": "Liang", "given": "Mao-Chang" }, "orcid": "0000-0002-5294-9344" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "van-Cleve-J", "name": { "family": "van Cleve", "given": "Jeffrey" } } ] }, "title": "First Spitzer observations of Neptune: Detection of new hydrocarbons", "ispublished": "pub", "full_text_status": "restricted", "keywords": "Neptune, atmosphere; Spectroscopy; Infrared observations; Atmospheres, composition.", "note": "\u00a9 2008 Elsevier Inc.\nReceived 14 November 2007; revised 19 May 2008; available online 20 June 2008; October 2008 issue.\nThis work is based on observations made with the Spitzer Space Telescope, which is operated by the Jet Propulsion Laboratory, California Institute of Technology under a contract with NASA. M.C.L. and Y.L.Y. were supported in part by NASA Grant NAG5-13296 to the California Institute of Technology. We wish to thank Julianne Moses for her model vertical constituent profiles in advance of\npublication\u2014and for several extremely helpful discussions. The IRS was a collaborative venture between Cornell University and Ball Aerospace Corporation funded by NASA through the Jet Propulsion Laboratory and Ames Research Center.", "abstract": "We present the first spectra of Neptune taken with the Spitzer Space Telescope, highlighting the\nhigh-sensitivity, moderate-resolution 10\u201320 \u03bcm (500\u20131000 cm^(\u22121)) spectra. We report the discovery\nof methylacetylene (CH_3C_2H) and diacetylene (C_4H_2) with derived 0.1-mbar volume mixing ratios of\n(1.2\u00b10.1)\u00d710^(\u221210) and (3 \u00b11)\u00d710^(\u221212) respectively.", "date": "2008-10", "date_type": "published", "publication": "Icarus", "volume": "197", "number": "2", "publisher": "Elsevier", "pagerange": "585-589", "id_number": "CaltechAUTHORS:MEAica08", "issn": "0019-1035", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:MEAica08", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NAG5-13296" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/j.icarus.2008.05.023", "resource_type": "article", "pub_year": "2008", "author_list": "Meadows, Victoria S.; Orton, Glenn; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/tgsx3-pvt09", "eprint_id": 12325, "eprint_status": "archive", "datestamp": "2023-08-22 13:10:28", "lastmod": "2023-10-17 16:41:19", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Jiang-Xun", "name": { "family": "Jiang", "given": "Xun" }, "orcid": "0000-0001-8932-3807" }, { "id": "Pawson-Steven", "name": { "family": "Pawson", "given": "Steven" } }, { "id": "Camp-C-D", "name": { "family": "Camp", "given": "Charles D." } }, { "id": "Nielsen-J-E", "name": { "family": "Nielsen", "given": "J. Eric" } }, { "id": "Shia-Run-Lie", "name": { "family": "Shia", "given": "Run-Lie" }, "orcid": "0000-0003-1911-3120" }, { "id": "Liao-Ting", "name": { "family": "Liao", "given": "Ting" } }, { "id": "Limpasuvan-Varavut", "name": { "family": "Limpasuvan", "given": "Varavut" } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Interannual Variability and Trends of Extratropical Ozone. Part I: Northern Hemisphere", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2008 American Meteorological Society. \n\n(Manuscript received 31 October 2007, in final form 26 March 2008) \n\nWe thank D.E. Waliser, M. Allen, D. Feldman, A. Ingersoll, J. Perkins, J. Weibel, M. Gerstell, and two anonymous reviewers for useful inputs and helpful comments. Special thanks are due to R. Stolarski for his contribution to the ozone simulations, K. Jeev for deducing the missing O3 data using potential vorticity, L.M. Li for critical reading and editing of the manuscript, and R. Salawitch for improving presentation of results on O3 trends. NASA provided computational resources for running the GEOS-CCM through their high-performance computing initiative (the model was run on the \"Columbia\" computer at NASA Ames Research Center). This research was supported in part by NASA Grants NNG04GD76G and NNG04GN02G to the California Institute of Technology. S. Pawson and E. Nielsen were supported by NASA's Modeling and Analysis Program. V. Limpasuvan was supported by NSF Grants ATM-0213248 and ATM-0521002.\n\nPublished - JIAjas08a.pdf
", "abstract": "The authors apply principal component analysis (PCA) to the extratropical total column ozone from the combined merged ozone data product and the European Centre for Medium-Range Weather Forecasts assimilated ozone from January 1979 to August 2002. The interannual variability (IAV) of extratropical O3 in the Northern Hemisphere (NH) is characterized by four main modes. Attributable to dominant dynamical effects, these four modes account for nearly 60% of the total ozone variance in the NH. The patterns of variability are distinctly different from those derived for total O3 in the tropics. To relate the derived patterns of O3 to atmospheric dynamics, similar decompositions are performed for the 30\u2013100-hPa geopotential thickness. The results reveal intimate connections between the IAV of total ozone and the atmospheric circulation. \n\nThe first two leading modes are nearly zonally symmetric and represent the connections to the annular modes and the quasi-biennial oscillation. The other two modes exhibit in-quadrature, wavenumber-1 structures that, when combined, describe the displacement of the polar vortices in response to planetary waves. In the NH, the extrema of these combined modes have preferred locations that suggest fixed topographical and land\u2013sea thermal forcing of the involved planetary waves. Similar spatial patterns and trends in extratropical column ozone are simulated by the Goddard Earth Observation System chemistry\u2013climate model (GEOS-CCM). \n\nThe decreasing O3 trend is captured in the first mode. The largest trend occurs at the North Pole, with values \u223c\u22121 Dobson Unit (DU) yr^\u22121. There is almost no trend in tropical O3. The trends derived from PCA are confirmed using a completely independent method, empirical mode decomposition, for zonally averaged O3 data. The O3 trend is also captured by mode 1 in the GEOS-CCM, but the decrease is substantially larger than that in the real atmosphere.", "date": "2008-10", "date_type": "published", "publication": "Journal of the Atmospheric Sciences", "volume": "65", "number": "10", "publisher": "American Meteorological Society", "pagerange": "3013-3029", "id_number": "CaltechAUTHORS:JIAjas08a", "issn": "0022-4928", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:JIAjas08a", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NNG04GD76G" }, { "agency": "NASA", "grant_number": "NNG04GN02G" }, { "agency": "NSF", "grant_number": "ATM-0213248" }, { "agency": "NSF", "grant_number": "ATM-0521002" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1175/2008JAS2665.1", "primary_object": { "basename": "JIAjas08a.pdf", "url": "https://authors.library.caltech.edu/records/tgsx3-pvt09/files/JIAjas08a.pdf" }, "resource_type": "article", "pub_year": "2008", "author_list": "Jiang, Xun; Pawson, Steven; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/trkpy-epq28", "eprint_id": 11958, "eprint_status": "archive", "datestamp": "2023-08-22 12:51:51", "lastmod": "2023-10-17 16:00:42", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Chahine-M-T", "name": { "family": "Chahine", "given": "M. T." } }, { "id": "Chen-Luke", "name": { "family": "Chen", "given": "Luke" } }, { "id": "Dimotakis-P-E", "name": { "family": "Dimotakis", "given": "Paul" } }, { "id": "Jiang-Xun", "name": { "family": "Jiang", "given": "Xun" }, "orcid": "0000-0001-8932-3807" }, { "id": "Li-Qinbi", "name": { "family": "Li", "given": "Qinbi" } }, { "id": "Pagano-T-S", "name": { "family": "Pagano", "given": "Thomas" } }, { "id": "Randerson-J-T", "name": { "family": "Randerson", "given": "James T." }, "orcid": "0000-0001-6559-7387" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Satellite remote sounding of mid-tropospheric CO_2", "ispublished": "pub", "full_text_status": "public", "keywords": "CO2; AIRS; infrared", "note": "Copyright 2008 by the American Geophysical Union. \n\nReceived 13 June 2008; accepted 6 August 2008; published 9 September 2008. \n\nWe thank Charles E. Miller of JPL for valuable comments and suggestions on the manuscript. We thank the reviewers, Steve Pawson and the other anonymous reviewers, for their thorough and constructive reviews. This work was carried out at the Jet Propulsion Laboratory, California Institute of Technology under contract with the National Aeronautic and Space Administration.\n\nPublished - CHAgrl08.pdf
Supplemental Material - CHAgrl08.avi
Supplemental Material - CHAgrl08readme
Supplemental Material - CHAgrlfigS1.tif
Supplemental Material - CHAgrlfigS2.tif
Supplemental Material - CHAgrlfigS3.tif
", "abstract": "Human activity has increased the concentration of the earth's atmospheric carbon dioxide, which plays a direct role in contributing to global warming. Mid-tropospheric CO_2 retrieved by the Atmospheric Infrared Sounder shows a substantial spatiotemporal variability that is supported by in situ aircraft measurements. The distribution of middle tropospheric CO_2 is strongly influenced by surface sources and large-scale circulations such as the mid-latitude jet streams and by synoptic weather systems, most notably in the summer hemisphere. In addition, the effects of stratosphere-troposphere exchange are observed during a final stratospheric warming event. The results provide the means to understand the sources and sinks and the lifting of CO_2 from surface layers into the free troposphere and its subsequent transport around the globe. These processes are not adequately represented in three chemistry-transport models that have been used to study carbon budgets.", "date": "2008-09", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "35", "number": "17", "publisher": "American Geophysical Union", "pagerange": "Art. No. L17807", "id_number": "CaltechAUTHORS:CHAgrl08", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:CHAgrl08", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA/JPL/Caltech" } ] }, "local_group": { "items": [ { "id": "GALCIT" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2008GL035022", "primary_object": { "basename": "CHAgrl08.avi", "url": "https://authors.library.caltech.edu/records/trkpy-epq28/files/CHAgrl08.avi" }, "related_objects": [ { "basename": "CHAgrl08.pdf", "url": "https://authors.library.caltech.edu/records/trkpy-epq28/files/CHAgrl08.pdf" }, { "basename": "CHAgrl08readme", "url": "https://authors.library.caltech.edu/records/trkpy-epq28/files/CHAgrl08readme" }, { "basename": "CHAgrlfigS1.tif", "url": "https://authors.library.caltech.edu/records/trkpy-epq28/files/CHAgrlfigS1.tif" }, { "basename": "CHAgrlfigS2.tif", "url": "https://authors.library.caltech.edu/records/trkpy-epq28/files/CHAgrlfigS2.tif" }, { "basename": "CHAgrlfigS3.tif", "url": "https://authors.library.caltech.edu/records/trkpy-epq28/files/CHAgrlfigS3.tif" } ], "resource_type": "article", "pub_year": "2008", "author_list": "Chahine, M. T.; Chen, Luke; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/6yydw-n8d07", "eprint_id": 48945, "eprint_status": "archive", "datestamp": "2023-08-22 12:45:18", "lastmod": "2023-10-17 20:33:54", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Liang-Mao-Chang", "name": { "family": "Liang", "given": "Mao-Chang" }, "orcid": "0000-0002-5294-9344" }, { "id": "Li-King-Fai", "name": { "family": "Li", "given": "King-Fai" }, "orcid": "0000-0003-0150-2910" }, { "id": "Shia-Run-Lie", "name": { "family": "Shia", "given": "Run-Lie" }, "orcid": "0000-0003-1911-3120" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Short-period solar cycle signals in the ionosphere observed by FORMOSAT-3/COSMIC", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2008 The American Geophysical Union.\n\nReceived 23 April 2008; Revised 30 June 2008; Accepted 11 July 2008; Published 15 August 2008.\n\nWe thank S. Sander, K. K. Tung, and D. Waliser for valuable inputs. This work was supported in part by an NSC grant 96-2628-M-001-018 to the Academia Sinica. KFL, RLS and YLY\nwere supported in part by NASA MAP program via JPL grant P480501 to the California Institute of Technology. The authors acknowledge the NSPO and UCAR CDAAC groups for providing FORMOSAT-3/COSMIC GPS radio occultation data.\n\nPublished - grl24763.pdf
", "abstract": "We analyze 2 years of the FORMOSAT-3/COSMIC GPS radio occultation data to study the response of the Earth's ionosphere to the solar rotation (27-day) induced solar flux variations. Here we report electron density variations in the ionosphere (\u223c100\u2013500 km) associated with the 27-day solar cycle. The peak-to-peak variation in electron density at low latitudes in the F2 region is about \u223c10^4\u201310^5 electrons cm^(\u22123) or 20\u201340%, and can be as high as 60% depending on altitude, latitude, and season. The half and double periods of the 27-day are also observed at an amplitude comparable to that of the 27-day. The results place useful constraints for modeling chemical and dynamical processes in the ionosphere.", "date": "2008-08-15", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "35", "number": "15", "publisher": "American Geophysical Union", "pagerange": "Art. No. L15818", "id_number": "CaltechAUTHORS:20140826-150215551", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140826-150215551", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "National Science Council (Taipei)", "grant_number": "96-2628-M-001-018" }, { "agency": "JPL", "grant_number": "P480501" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2008GL034433", "primary_object": { "basename": "grl24763.pdf", "url": "https://authors.library.caltech.edu/records/6yydw-n8d07/files/grl24763.pdf" }, "resource_type": "article", "pub_year": "2008", "author_list": "Liang, Mao-Chang; Li, King-Fai; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/htfg4-fn447", "eprint_id": 48888, "eprint_status": "archive", "datestamp": "2023-08-22 12:38:22", "lastmod": "2023-10-17 20:30:56", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Parkinson-C-D", "name": { "family": "Parkinson", "given": "Christopher D." }, "orcid": "0000-0002-5722-2224" }, { "id": "Liang-Mao-Chang", "name": { "family": "Liang", "given": "Mao-Chang" }, "orcid": "0000-0002-5294-9344" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Kirschvink-J-L", "name": { "family": "Kirschvink", "given": "Joseph L." }, "orcid": "0000-0001-9486-6689" } ] }, "title": "Habitability of Enceladus: Planetary Conditions for Life", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 2008 Springer Science + Business Media B.V.\n\nReceived: 11 October 2007; Accepted: 10 April 2008;\nPublished online: 20 June 2008.\n\nWe thank A. C. Barr and W. McKinnon for valuable discussions and communication of results prior to publication. We thank C. Boxe, P. Chen, B. A. D'Amore, X. Guo, H. Hartman, L. Kuai, R. Pappalardo, and R.-L. Shia for critical reading of the manuscript and helpful discussions. This research is\nsupported in part by the Cassini Project and the Jet Propulsion Laboratory.", "abstract": "The prolific activity and presence of a plume on Saturn's tiny moon Enceladus offers us a unique opportunity to sample the interior composition of an icy satellite, and to look for interesting chemistry and possible signs of life. Based on studies of the potential habitability of Jupiter's moon Europa, icy satellite oceans can be habitable if they are chemically mixed with the overlying ice shell on Myr time scales. We hypothesize that Enceladus' plume, tectonic processes, and possible liquid water ocean may create a complete and sustainable geochemical cycle that may allow it to support life. We discuss evidence for surface/ocean material exchange on Enceladus based on the amounts of silicate dust material present in the Enceladus' plume particles. Microphysical cloud modeling of Enceladus' plume shows that the particles originate from a region of Enceladus' near surface where the temperature exceeds 190 K. This could be consistent with a shear-heating origin of Enceladus' tiger stripes, which would indicate extremely high temperatures (\u223c250\u2013273 K) in the subsurface shear fault zone, leading to the generation of subsurface liquid water, chemical equilibration between surface and subsurface ices, and crustal recycling on a time scale of 1 to 5 Myr. Alternatively, if the tiger stripes form in a mid-ocean-ridge-type mechanism, a half-spreading rate of 1 m/year is consistent with the observed regional heat flux of 250 mW m\u22122 and recycling of south polar terrain crust on a 1 to 5 Myr time scale as well.", "date": "2008-08", "date_type": "published", "publication": "Origins of life and evolution of the biosphere", "volume": "38", "number": "4", "publisher": "Springer", "pagerange": "355-369", "id_number": "CaltechAUTHORS:20140826-084746711", "issn": "0169-6149", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140826-084746711", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Cassini Project" }, { "agency": "JPL" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1007/s11084-008-9135-4", "resource_type": "article", "pub_year": "2008", "author_list": "Parkinson, Christopher D.; Liang, Mao-Chang; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/4bjs0-v7q86", "eprint_id": 12762, "eprint_status": "archive", "datestamp": "2023-09-14 18:45:06", "lastmod": "2023-10-23 20:44:27", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Tian-Baijun", "name": { "family": "Tian", "given": "Baijun" } }, { "id": "Waliser-D-E", "name": { "family": "Waliser", "given": "Duane E." } }, { "id": "Kahn-R-A", "name": { "family": "Kahn", "given": "Ralph A." } }, { "id": "Li-Qinbi", "name": { "family": "Li", "given": "Qinbi" } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Tyranowski-T", "name": { "family": "Tyranowski", "given": "Tomasz" } }, { "id": "Geogdzhayev-I-V", "name": { "family": "Geogdzhayev", "given": "Igor V." } }, { "id": "Mischenko-M-I", "name": { "family": "Mischenko", "given": "Michael I." } }, { "id": "Torres-O", "name": { "family": "Torres", "given": "Omar" } }, { "id": "Smimov-A", "name": { "family": "Smimov", "given": "Alexander" } } ] }, "title": "Does the Madden-Julian Oscillation influence aerosol variability?", "ispublished": "pub", "full_text_status": "public", "keywords": "MJO, AOT, AI", "note": "\u00a9 2008. American Geophysical Union. \n\nReceived 10 September 2007; accepted 18 February 2008; published 28 June 2008. \n\nThis research was performed at the Jet Propulsion Laboratory (JPL), California Institute of Technology (Caltech), under a contract with NASA. B. Tian and D. Waliser were jointly supported by the Research and Technology Development program, Human Resources Development fund, and AIRS project at JPL as well as NASA Modeling, Analysis and Prediction program. The work of R. Kahn was supported in part by NASA Climate and Radiation Research and Analysis program, under H. Maring, and in part by the EOS-MISR instrument project. Y. Yung was supported by NASA grant NNG04GD76G to Caltech and T. Tyranowski acknowledges support by the Caltech SURF program in 2006. We also want to thank Eric Fetzer, Jianglong Zhang, and three anonymous reviewers for constructive comments and many scientists at the 2007 Gordon Research Conference on Radiation and Climate for helpful discussions.\n\nPublished - TIAjgrd08.pdf
", "abstract": "We investigate the modulation of aerosols by the Madden-Julian Oscillation (MJO) using multiple, global satellite aerosol products: aerosol index (AI) from the Total Ozone Mapping Spectrometer (TOMS) on Nimbus-7, and aerosol optical thickness (AOT) from the Moderate Resolution Imaging Spectroradiometer (MODIS) on Terra and Aqua and the Advanced Very High Resolution Radiometer (AVHRR) on NOAA satellites. A composite MJO analysis indicates that large variations in the TOMS AI and MODIS/AVHRR AOT are found over the equatorial Indian and western Pacific Oceans where MJO convection is active, as well as the tropical Africa and Atlantic Ocean where MJO convection is weak but the background aerosol level is high. A strong inverse linear relationship between the TOMS AI and rainfall anomalies, but a weaker, less coherent positive correlation between the MODIS/AVHRR AOT and rainfall anomalies, were found. The MODIS/AVHRR pattern is consistent with ground-based Aerosol Robotic Network data. These results indicate that the MJO and its associated cloudiness, rainfall, and circulation variability systematically influence the variability in remote sensing aerosol retrieval results. Several physical and retrieval algorithmic factors that may contribute to the observed aerosol-rainfall relationships are discussed. Preliminary analysis indicates that cloud contamination in the aerosol retrievals is likely to be a major contributor to the observed relationships, although we cannot exclude possible contributions from other physical mechanisms. Future research is needed to fully understand these complex aerosol-rainfall relationships.", "date": "2008-06-28", "date_type": "published", "publication": "Journal of Geophysical Research D", "volume": "113", "publisher": "American Geophysical Union", "pagerange": "D12215", "id_number": "CaltechAUTHORS:TIAjgrd08", "issn": "0148-0227", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:TIAjgrd08", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NNG04GD76G" }, { "agency": "Summer Undergraduate Research Fellowship (SURF), Caltech" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2007JD009372", "primary_object": { "basename": "TIAjgrd08.pdf", "url": "https://authors.library.caltech.edu/records/4bjs0-v7q86/files/TIAjgrd08.pdf" }, "resource_type": "article", "pub_year": "2008", "author_list": "Tian, Baijun; Waliser, Duane E.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/yvzjw-01g33", "eprint_id": 12765, "eprint_status": "archive", "datestamp": "2023-09-14 18:45:13", "lastmod": "2023-10-23 20:44:30", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Liang-Mao-Chang", "name": { "family": "Liang", "given": "Mao-Chang" }, "orcid": "0000-0002-5294-9344" }, { "id": "Blake-G-A", "name": { "family": "Blake", "given": "Geoffrey A." }, "orcid": "0000-0003-0787-1610" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Seasonal cycle of C16O16O, C16O17O, and C16O18O in the middle atmosphere: Implications for mesospheric dynamics and biogeochemical sources and sinks of CO2", "ispublished": "pub", "full_text_status": "public", "keywords": "Isotopic composition, photochemistry, middle atmosphere", "note": "\u00a9 2008. American Geophysical Union. \n\nReceived 3 January 2007; accepted 17 December 2008; published 21 June 2008. \n\nThis work was supported in part by an NSC grant 96-2628-M-001-018 to the Academia Sinica and an NSF grant ATM-0529268 to the California Institute of Technology. Special thanks are due Xun Jiang and Run-Lie Shia for assisting in the construction of stream functions needed for the 2-D models for invaluable discussions and John Eiler for pointing out the reference describing the CO2-water isotopic exchange in firn.\n\nPublished - LIAjgrd08.pdf
", "abstract": "The isotopic anomaly of oxygen in atmospheric CO2 is caused by exchange reactions with isotopically anomalous O(1D) in the middle atmosphere. In the stratosphere, the major source of O(1D) is O3 photolysis; O3 is known to possess mass-independent isotopic composition, with \u03b4 49O3 \u2248 \u03b4 50O3 \u2248 100\u2030 relative to atmospheric O2. Higher in the mesosphere, Lyman \u03b1-driven photodissociation of O2 provides a more important source of heavy O(1D) than O3 photolysis. Here we present a two-dimensional simulation of the isotopic composition of CO2 from the surface to an altitude of \u223c130 km that adequately reproduce the observed seasonal cycle of CO2 in the upper troposphere and the age of air in the stratosphere. Our model results suggest that stratospheric-tropospheric exchange not only modifies the level of heavy CO2 in the troposphere, but also influences its seasonal cycle. Thus the isotopic composition of CO2 in the troposphere/biosphere could be affected by the downwelling air from the stratosphere. The predicted size of the effect is detectable by current instrumentation. Implications for the use of the isotopic composition of CO2 to constrain the gross carbon flux between the atmosphere and terrestrial biosphere and the dynamics in the remote mesosphere are discussed.", "date": "2008-06-21", "date_type": "published", "publication": "Journal of Geophysical Research D", "volume": "113", "publisher": "American Geophysical Union", "pagerange": "D12305", "id_number": "CaltechAUTHORS:LIAjgrd08", "issn": "0148-0227", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:LIAjgrd08", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "National Science Council (Taipei)", "grant_number": "96-2628-M-001-018" }, { "agency": "NSF", "grant_number": "ATM-0529268" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2007JD008392", "primary_object": { "basename": "LIAjgrd08.pdf", "url": "https://authors.library.caltech.edu/records/yvzjw-01g33/files/LIAjgrd08.pdf" }, "resource_type": "article", "pub_year": "2008", "author_list": "Liang, Mao-Chang; Blake, Geoffrey A.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/7sny1-fty44", "eprint_id": 48848, "eprint_status": "archive", "datestamp": "2023-09-15 04:49:48", "lastmod": "2023-10-23 21:10:24", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Liang-Mao-Chang", "name": { "family": "Liang", "given": "Mao-Chang" }, "orcid": "0000-0002-5294-9344" }, { "id": "Blake-G-A", "name": { "family": "Blake", "given": "Geoffrey A." }, "orcid": "0000-0003-0787-1610" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Seasonal cycle of C^(16)O^(16)O, C^(16)O^(17)O, and C^(16)O^(18)O in the middle atmosphere: Implications for mesospheric dynamics and biogeochemical sources and sinks of CO_2", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2008 The American Geophysical Union.\n\nReceived 3 January 2007; Revised 24 November 2007; Accepted 17 December 2008; Published 21 June 2008.\n\nThis work was supported in part by an NSC grant 96-2628-M-001-018 to the Academia Sinica and an NSF grant ATM-0529268 to the California Institute of Technology. Special thanks are due Xun Jiang and Run-Lie Shia for assisting in the construction of stream functions needed for the 2-D models for invaluable discussions and John Eiler for pointing out the reference describing the CO2-water isotopic\nexchange in firn.\n\nPublished - jgrd13771.pdf
Supplemental Material - jgrd13771-sup-0001-t01.txt
Supplemental Material - jgrd13771-sup-0002-t02.txt
", "abstract": "The isotopic anomaly of oxygen in atmospheric CO_2 is caused by exchange reactions with isotopically anomalous O(^1D) in the middle atmosphere. In the stratosphere, the major source of O(^1D) is O_3 photolysis; O_3 is known to possess mass-independent isotopic composition, with \u03b4^(49)O_3 \u2248 \u03b4^(50)O_3 \u2248 100\u2030 relative to atmospheric O_2. Higher in the mesosphere, Lyman \u03b1-driven photodissociation of O2 provides a more important source of heavy O(^1D) than O_3 photolysis. Here we present a two-dimensional simulation of the isotopic composition of CO_2 from the surface to an altitude of \u223c130 km that adequately reproduce the observed seasonal cycle of CO_2 in the upper troposphere and the age of air in the stratosphere. Our model results suggest that stratospheric-tropospheric exchange not only modifies the level of heavy CO_2 in the troposphere, but also influences its seasonal cycle. Thus the isotopic composition of CO_2 in the troposphere/biosphere could be affected by the downwelling air from the stratosphere. The predicted size of the effect is detectable by current instrumentation. Implications for the use of the isotopic composition of CO_2 to constrain the gross carbon flux between the atmosphere and terrestrial biosphere and the dynamics in the remote mesosphere are discussed.", "date": "2008-06-21", "date_type": "published", "publication": "Journal of Geophysical Research D", "volume": "113", "number": "D12", "publisher": "American Geophysical Union", "pagerange": "Art. No. D12305", "id_number": "CaltechAUTHORS:20140825-113411589", "issn": "0148-0227", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140825-113411589", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "National Science Council (Taipei)", "grant_number": "96-2628-M-001-018" }, { "agency": "NSF", "grant_number": "ATM-0529268" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2007JD008392", "primary_object": { "basename": "jgrd13771-sup-0001-t01.txt", "url": "https://authors.library.caltech.edu/records/7sny1-fty44/files/jgrd13771-sup-0001-t01.txt" }, "related_objects": [ { "basename": "jgrd13771-sup-0002-t02.txt", "url": "https://authors.library.caltech.edu/records/7sny1-fty44/files/jgrd13771-sup-0002-t02.txt" }, { "basename": "jgrd13771.pdf", "url": "https://authors.library.caltech.edu/records/7sny1-fty44/files/jgrd13771.pdf" } ], "resource_type": "article", "pub_year": "2008", "author_list": "Liang, Mao-Chang; Blake, Geoffrey A.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/75gsk-rk808", "eprint_id": 12750, "eprint_status": "archive", "datestamp": "2023-08-22 11:59:56", "lastmod": "2023-10-17 20:28:51", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Natraj-V", "name": { "family": "Natraj", "given": "Vijay" }, "orcid": "0000-0003-3154-9429" }, { "id": "Boesch-H", "name": { "family": "Boesch", "given": "Hartmut" }, "orcid": "0000-0003-3944-9879" }, { "id": "Spurr-R-J-D", "name": { "family": "Spurr", "given": "Robert J. D." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Retrieval of XCO2 from simulated Orbiting Carbon Observatory measurements using the fast linearized R-2OS radiative transfer model", "ispublished": "pub", "full_text_status": "public", "keywords": "retrieval, OCO, radiative transfer", "note": "Copyright 2008 by the American Geophysical Union. \n\nReceived 29 May 2007; revised 23 August 2007; accepted 11 December 2007; published 14 June 2008. \n\nThe research described in this paper was performed for the Orbiting Carbon Observatory Project at the Jet Propulsion Laboratory, California Institute of Technology, under contracts with NASA. This work was supported in part by NASA grant NAG1-1806. The authors would like to thank Hari Nair for assistance with the forward model and error analysis simulations; Ralph Kahn for discussions on aerosols; Michael Mishchenko, Joop Hovenier and Johan de Haan for providing T matrix and Mie codes; Dave Crisp for assistance with detector optics; Run-Lie Shia and Dan Feldman for helpful comments on the manuscript; and two anonymous reviewers for suggestions to revise the manuscript.\n\nPublished - NATjgrd08.pdf
", "abstract": "In a recent paper, we introduced a novel technique to compute the polarization in a vertically inhomogeneous, scattering-absorbing medium using a two orders of scattering (2OS) radiative transfer (RT) model. The 2OS computation is an order of magnitude faster than a full multiple scattering scalar calculation and can be implemented as an auxiliary code to compute polarization in operational retrieval algorithms. In this paper, we employ the 2OS model for polarization in conjunction with a scalar RT model (Radiant) to simulate backscatter measurements in near infrared (NIR) spectral regions by space-based instruments such as the Orbiting Carbon Observatory (OCO). Computations are performed for six different sites and two seasons, representing a variety of viewing geometries, surface and aerosol types. The aerosol extinction (at 13000 cm^\u22121) was varied from 0 to 0.3. The radiance errors using the Radiant/2OS (R-2OS) RT model are an order of magnitude (or more) smaller than errors arising from the use of the scalar model alone. In addition, we perform a linear error analysis study to show that the errors in the retrieved column-averaged dry air mole fraction of CO2 (XCO2) using the R-2OS model are much lower than the \"measurement\" noise and smoothing errors appearing in the inverse model. On the other hand, we show that use of the scalar model alone induces X CO2 errors that could dominate the retrieval error budget.", "date": "2008-06-14", "date_type": "published", "publication": "Journal of Geophysical Research D", "volume": "113", "number": "11", "publisher": "American Geophysical Union", "pagerange": "D11212", "id_number": "CaltechAUTHORS:NATjgrd08", "issn": "0148-0227", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:NATjgrd08", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NAG1-1806" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2007JD009017", "primary_object": { "basename": "NATjgrd08.pdf", "url": "https://authors.library.caltech.edu/records/75gsk-rk808/files/NATjgrd08.pdf" }, "resource_type": "article", "pub_year": "2008", "author_list": "Natraj, Vijay; Boesch, Hartmut; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/ragg2-qsc56", "eprint_id": 12646, "eprint_status": "archive", "datestamp": "2023-08-22 11:59:46", "lastmod": "2023-10-17 20:24:13", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Feldman-D-R", "name": { "family": "Feldman", "given": "D. R." } }, { "id": "Liou-K-N", "name": { "family": "Liou", "given": "K. N." } }, { "id": "Shia-R-L", "name": { "family": "Shia", "given": "R. L." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Y. L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "On the information content of the thermal infrared cooling rate profile from satellite instrument measurements", "ispublished": "pub", "full_text_status": "public", "keywords": "Cooling rate, information content, remote sensing", "note": "Copyright 2008 by the American Geophysical Union. \n\nReceived 4 June 2007; revised 25 January 2008; accepted 25 February 2008; published 13 June 2008. \n\nThis research was supported by the NASA Earth Systems Science Fellowship, grant NNG05GP90H. Yung was supported by NASA grant to JPL under the MAP program. Invaluable technical support was provided by Tony Clough, Mark Iacono, and Mark Shepard at AER, Inc. Other support was provided by Marty Mlynczak and David Johnson of the NASA Langley Research Center. The author would also like to acknowledge the help provided by the Yuk Yung Radiation Group including Jack Margolis, Vijay Natraj, Xin Guo, Kuai Le, King-Fai Li, Mao-Chang Liang, and Ross Cheung. Finally, this work benefited immensely from the comments of the three anonymous reviewers.\n\nPublished - FELjgrd08a.pdf
", "abstract": "This work investigates how remote sensing of the quantities required to calculate clear-sky cooling rate profiles propagates into cooling rate profile knowledge. The formulation of a cooling rate profile error budget is presented for clear-sky scenes given temperature, water vapor, and ozone profile uncertainty. Using linear propagation of error analysis, an expression for the cooling rate profile covariance matrix is given. Some of the features of the cooling rate covariance matrix are discussed, and it is found that nonzero error correlations in the temperature, water vapor, and ozone retrieval profiles must be considered to produce an unbiased estimate of cooling rate profile variance and the covariance structure. To that end, the exclusion of the details of this error correlation leads to an underestimation of the cooling rate profile uncertainty. This work then examines the assumptions made in the course of deriving the expression for the cooling rate covariance matrix by using ERA-40 Reanalysis data. It is established that the assumptions of linear error propagation and Gaussian statistics are generally tenable. Next, the information content of thermal infrared spectra with respect to clear-sky cooling rate profiles is investigated. Several formerly- and currently-operational spectrometers are compared with different spectral coverage, resolution, signal-to-noise ratio. Among these, IASI is found to have the ability to provide the greatest amount of information on the cooling rate profile. Also, it may be scientifically useful to develop far-infrared missions in terms of cooling rate profile analysis.", "date": "2008-06-13", "date_type": "published", "publication": "Journal of Geophysical Research D", "volume": "113", "publisher": "American Geophysical Union", "pagerange": "D11118", "id_number": "CaltechAUTHORS:FELjgrd08a", "issn": "0148-0227", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:FELjgrd08a", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NNG05GP90H" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2007JD009041", "primary_object": { "basename": "FELjgrd08a.pdf", "url": "https://authors.library.caltech.edu/records/ragg2-qsc56/files/FELjgrd08a.pdf" }, "resource_type": "article", "pub_year": "2008", "author_list": "Feldman, D. R.; Liou, K. N.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/sqzvh-wpq16", "eprint_id": 12767, "eprint_status": "archive", "datestamp": "2023-08-22 11:50:08", "lastmod": "2023-10-17 20:54:37", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Su-Hui", "name": { "family": "Su", "given": "Hui" }, "orcid": "0000-0003-1265-9702" }, { "id": "Jiang-J-H", "name": { "family": "Jiang", "given": "Jonathan H." } }, { "id": "Gu-Yu", "name": { "family": "Gu", "given": "Yu" }, "orcid": "0000-0002-3412-0794" }, { "id": "Neelin-J-D", "name": { "family": "Neelin", "given": "J. David" }, "orcid": "0000-0001-9414-9962" }, { "id": "Kahn-B-H", "name": { "family": "Kahn", "given": "Brian H." } }, { "id": "Feldman-D", "name": { "family": "Feldman", "given": "Daniel" } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Waters-J-W", "name": { "family": "Waters", "given": "Joe W." } }, { "id": "Livesey-N-J", "name": { "family": "Livesey", "given": "Nathaniel J." } }, { "id": "Santee-M-L", "name": { "family": "Santee", "given": "Michelle L." } }, { "id": "Read-W-G", "name": { "family": "Read", "given": "William G." } } ] }, "title": "Variations of tropical upper tropospheric clouds with sea surface temperature and implications for radiative effects", "ispublished": "pub", "full_text_status": "public", "keywords": "Clouds, SST, cloud feedback", "note": "\u00a92008. American Geophysical Union. \n\nReceived 19 November 2007; revised 18 January 2008; accepted 18 February 2008; published 31 May 2008. \n\nWe thank MLS and AIRS colleagues for data support. Discussions with A. Dessler, Q. Fu, B. Lin, R. S. Lindzen, and R. Rondanelli were helpful. This work was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under contract with NASA. JDN is supported by National Science Foundation Grant ATM-0645200 and NOAA Grant NA05OAR4311134. We thank three anonymous reviewers for helpful comments and suggestions.\n\nPublished - SUHjgrd08.pdf
", "abstract": "The variations of tropical upper tropospheric (UT) clouds with sea surface temperature (SST) are analyzed using effective cloud fraction from the Atmospheric Infrared Sounder (AIRS) on Aqua and ice water content (IWC) from the Microwave Limb Sounder (MLS) on Aura. The analyses are limited to UT clouds above 300 hPa. Our analyses do not suggest a negative correlation of tropical-mean UT cloud fraction with the cloud-weighted SST (CWT). Instead, both tropical-mean UT cloud fraction and IWC are found to increase with CWT, although their correlations with CWT are rather weak. The rate of increase of UT cloud fraction with CWT is comparable to that of precipitation, while the UT IWC and ice water path (IWP) increase more strongly with CWT. The radiative effect of UT clouds is investigated, and they are shown to provide a net warming at the top of the atmosphere. An increase of IWP with SST yields an increase of net warming that corresponds to a positive feedback, until the UT IWP exceeds a value about 50% greater than presently observed by MLS. Further increases of the UT IWP would favor the shortwave cooling effect, causing a negative feedback. Sensitivities of UT cloud forcing to the uncertainties in UT CFR and IWC measurements are discussed.", "date": "2008-05-31", "date_type": "published", "publication": "Journal of Geophysical Research D", "volume": "113", "publisher": "American Geophysical Union", "pagerange": "D10211", "id_number": "CaltechAUTHORS:SUHjgrd08", "issn": "0148-0227", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:SUHjgrd08", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA" }, { "agency": "National Science Foundation", "grant_number": "ATM-0645200" }, { "agency": "National Oceanic and Atmospheric Administration", "grant_number": "NA05OAR4311134" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2007JD009624", "primary_object": { "basename": "SUHjgrd08.pdf", "url": "https://authors.library.caltech.edu/records/sqzvh-wpq16/files/SUHjgrd08.pdf" }, "resource_type": "article", "pub_year": "2008", "author_list": "Su, Hui; Jiang, Jonathan H.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/7ddhc-95143", "eprint_id": 36516, "eprint_status": "archive", "datestamp": "2023-08-22 09:49:35", "lastmod": "2023-10-20 23:15:33", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Li-Liming", "name": { "family": "Li", "given": "Liming" }, "orcid": "0000-0002-5257-9849" }, { "id": "Ingersoll-A-P", "name": { "family": "Ingersoll", "given": "Andrew P." }, "orcid": "0000-0002-2035-9198" }, { "id": "Jiang-Xun", "name": { "family": "Jiang", "given": "Xun" }, "orcid": "0000-0001-8932-3807" }, { "id": "Feldman-D", "name": { "family": "Feldman", "given": "Daniel" } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Lorenz energy cycle of the global atmosphere based on reanalysis datasets", "ispublished": "pub", "full_text_status": "public", "keywords": "energy cycle; global atmosphere; conversion of energy", "note": "\u00a9 2007 by the American Geophysical Union. Received 12 March 2007; revised 10 July 2007; accepted 25 July 2007; published 24 August 2007.\n\nPublished - 2007GL029985.pdf
Supplemental Material - grl23161-sup-0001-readme.txt
Supplemental Material - grl23161-sup-0002-fs01.tif
Supplemental Material - grl23161-sup-0003-fs02.tif
Supplemental Material - grl23161-sup-0004-fs03.tif
Supplemental Material - grl23161-sup-0005-fs04.tif
Supplemental Material - grl23161-sup-0006-fs05.tif
Supplemental Material - grl23161-sup-0007-fs06.tif
Supplemental Material - grl23161-sup-0008-ts01.txt
Supplemental Material - grl23161-sup-0009-ts02.txt
Supplemental Material - grl23161-sup-0010-ts03.txt
Supplemental Material - grl23161-sup-0011-t01.txt
", "abstract": "The mean state of the global atmospheric energy cycle is re-examined using the two reanalysis datasets \u2014 NCEP2 and ERA40 (1979\u20132001). The general consistency between the two datasets suggests that the present estimates of the energy cycle are probably the most reliable ones. The comparison between the present and a previous study shows noticeable discrepancies in some of the energy components and conversion rates. The current estimate of the transformations from mean potential energy to mean kinetic energy C(P_M, K_M) further suggests that the near-surface processes play an important role in the conversion rate C(P_M, K_M), along with the Ferrel cell and Hadley cells, which probably change the direction of the conversion rate\nC(P_M, K_M).", "date": "2007-08-28", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "34", "number": "16", "publisher": "American Geophysical Union", "pagerange": "Art. No. L16813", "id_number": "CaltechAUTHORS:20130122-143142049", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20130122-143142049", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2007GL029985", "primary_object": { "basename": "grl23161-sup-0002-fs01.tif", "url": "https://authors.library.caltech.edu/records/7ddhc-95143/files/grl23161-sup-0002-fs01.tif" }, "related_objects": [ { "basename": "grl23161-sup-0003-fs02.tif", "url": "https://authors.library.caltech.edu/records/7ddhc-95143/files/grl23161-sup-0003-fs02.tif" }, { "basename": "grl23161-sup-0005-fs04.tif", "url": "https://authors.library.caltech.edu/records/7ddhc-95143/files/grl23161-sup-0005-fs04.tif" }, { "basename": "grl23161-sup-0006-fs05.tif", "url": "https://authors.library.caltech.edu/records/7ddhc-95143/files/grl23161-sup-0006-fs05.tif" }, { "basename": "grl23161-sup-0008-ts01.txt", "url": "https://authors.library.caltech.edu/records/7ddhc-95143/files/grl23161-sup-0008-ts01.txt" }, { "basename": "2007GL029985.pdf", "url": "https://authors.library.caltech.edu/records/7ddhc-95143/files/2007GL029985.pdf" }, { "basename": "grl23161-sup-0004-fs03.tif", "url": "https://authors.library.caltech.edu/records/7ddhc-95143/files/grl23161-sup-0004-fs03.tif" }, { "basename": "grl23161-sup-0007-fs06.tif", "url": "https://authors.library.caltech.edu/records/7ddhc-95143/files/grl23161-sup-0007-fs06.tif" }, { "basename": "grl23161-sup-0009-ts02.txt", "url": "https://authors.library.caltech.edu/records/7ddhc-95143/files/grl23161-sup-0009-ts02.txt" }, { "basename": "grl23161-sup-0010-ts03.txt", "url": "https://authors.library.caltech.edu/records/7ddhc-95143/files/grl23161-sup-0010-ts03.txt" }, { "basename": "grl23161-sup-0011-t01.txt", "url": "https://authors.library.caltech.edu/records/7ddhc-95143/files/grl23161-sup-0011-t01.txt" }, { "basename": "grl23161-sup-0001-readme.txt", "url": "https://authors.library.caltech.edu/records/7ddhc-95143/files/grl23161-sup-0001-readme.txt" } ], "resource_type": "article", "pub_year": "2007", "author_list": "Li, Liming; Ingersoll, Andrew P.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/f98mk-ygj77", "eprint_id": 18084, "eprint_status": "archive", "datestamp": "2023-08-22 09:41:50", "lastmod": "2023-10-20 15:34:19", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Liang-Mao-Chang", "name": { "family": "Liang", "given": "Mao-Chang" }, "orcid": "0000-0002-5294-9344" }, { "id": "Heays-A-N", "name": { "family": "Heays", "given": "Alan N." } }, { "id": "Lewis-B-R", "name": { "family": "Lewis", "given": "Brenton R." } }, { "id": "Gibson-S-T", "name": { "family": "Gibson", "given": "Stephen T." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Source of Nitrogen Isotope Anomaly in HCN in the Atmosphere of Titan", "ispublished": "pub", "full_text_status": "public", "keywords": "atmospheric effects; methods : numerical; molecular processes; planetary systems; planets and satellites : individual ( Titan); radiative transfer", "note": "\u00a9 2007 The American Astronomical Society.\nReceived 2007 May 7; accepted 2007 June 15; published 2007 July 12.\nThis research was supported by NASA grant NNG06GF33G\nand Cassini grant JPL.1256000 to the California Institute of\nTechnology, and Australian Research Council Discovery Program\ngrants DP0558962 and DP0773050 to the Australian National\nUniversity. Special thanks are due to D. Shemansky for\nproviding a high-resolution solar spectrum. We also thank K.\nDere, F. Mills, I. Ribas, and T. Woods for helpful discussion\non the issue of the solar EUV flux, and N. Heavens and R. L.\nShia for reading the manuscript. We thank W. DeMore, C.\nMiller, and H. Waite for valuable discussions on isotopic\nfractionation.\n\nPublished - LIAapjl07b.pdf
", "abstract": "The ^(14)N/^(15)N ratio for N_2 in the atmosphere of Titan was recently measured to be a factor of 2 higher than the corresponding ratio for HCN. Using a one-dimensional photochemical model with transport, we incorporate new isotopic photoabsorption and photodissociation cross sections of N_2, computed quantum-mechanically, and show that the difference in the ratio of ^(14)N/^(15)N between N_2 and HCN can be explained primarily by the photolytic fractionation of ^(14)N^(14)N and ^(14)N ^(15)N. The [HC^(14)N]/[HC^(15)N] ratio produced by N_2 photolysis alone is 23. This value, together with the observed ratio, constrains the flux of atomic nitrogen input from the top of the atmosphere to be in the range (1-2) \u00d7 10^9 atoms cm^(-2) s^(-1).", "date": "2007-08-01", "date_type": "published", "publication": "Astrophysical Journal Letters", "volume": "664", "number": "2", "publisher": "American Astronomical Society", "pagerange": "L115-L118", "id_number": "CaltechAUTHORS:20100430-093524383", "issn": "2041-8205", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20100430-093524383", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NNG06GF33G" }, { "agency": "Cassini", "grant_number": "JPL.1256000" }, { "agency": "Australian Research Council Discovery Program", "grant_number": "DP0558962" }, { "agency": "Australian Research Council Discovery Program", "grant_number": "DP0773050" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1086/520881", "primary_object": { "basename": "LIAapjl07b.pdf", "url": "https://authors.library.caltech.edu/records/f98mk-ygj77/files/LIAapjl07b.pdf" }, "resource_type": "article", "pub_year": "2007", "author_list": "Liang, Mao-Chang; Heays, Alan N.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/8vrdg-46440", "eprint_id": 48841, "eprint_status": "archive", "datestamp": "2023-08-22 09:32:06", "lastmod": "2023-10-17 20:28:36", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Liang-Mao-Chang", "name": { "family": "Liang", "given": "Mao-Chang" }, "orcid": "0000-0002-5294-9344" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Sources of the oxygen isotopic anomaly in atmospheric N_2O", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2007 The American Geophysical Union.\n\nReceived 2 August 2006; Revised 26 February 2007; Accepted 14 March 2007; Published 7 July 2007.\n\nThis work was supported in part by NSF grant ATM-9903790 to California Institute of Technology and NSC grant\n95-2111-M-001-009 to Academia Sinica. Special thanks is due X. Jiang for the derivation of the WACCM circulation used in two-dimensional modeling and W. DeMore, S. Prasad, and S. Sander on the discussion of the kinetics of N2O production in the atmosphere. We thank X. Jiang, V. Natraj,\nN. Heavens, C. Parkinson, and R.-L. Shia for their critical reading of the manuscript.\n\nPublished - jgrd13442.pdf
Supplemental Material - jgrd13442-sup-0001-t01.txt
", "abstract": "One-dimensional and two-dimensional models are used to investigate the isotopic composition of atmospheric N_2O. The sources of N_2O in the atmosphere are based on recent laboratory measurements of the N_2O quantum yield in the mixture of O_3/O_2/N_2 (Estupi\u00f1\u00e1n et al., 2002). Two recently proposed pathways (Estupi\u00f1\u00e1n et al., 2002; Prasad, 2005) are evaluated in the model. We find that the new atmospheric sources constitute a few percent of the total N_2O source, but can account for \u223c50\u2013100% of the \u0394^(17)O anomaly observed in N_2O. The essence of the mechanism is to transfer a heavy oxygen atom originally in O_3 to N_2O. The magnitude of \u0394^(17)O in N_2O is a linear function of the strength of these new N_2O sources. Laboratory and atmospheric measurements are proposed to confirm the chemical pathways. The potential of \u0394^(17)O in N_2O for providing a new tool to probe ozone levels in paleoatmospheres is discussed.", "date": "2007-07-16", "date_type": "published", "publication": "Journal of Geophysical Research D", "volume": "112", "number": "D13", "publisher": "American Geophysical Union", "pagerange": "Art. No. D13307", "id_number": "CaltechAUTHORS:20140825-101539027", "issn": "0148-0227", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140825-101539027", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "ATM-9903790" }, { "agency": "NSC", "grant_number": "95-2111-M-001-009" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2006JD007876", "primary_object": { "basename": "jgrd13442-sup-0001-t01.txt", "url": "https://authors.library.caltech.edu/records/8vrdg-46440/files/jgrd13442-sup-0001-t01.txt" }, "related_objects": [ { "basename": "jgrd13442.pdf", "url": "https://authors.library.caltech.edu/records/8vrdg-46440/files/jgrd13442.pdf" } ], "resource_type": "article", "pub_year": "2007", "author_list": "Liang, Mao-Chang and Yung, Yuk L." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/8d5br-9vc94", "eprint_id": 47486, "eprint_status": "archive", "datestamp": "2023-08-19 20:36:42", "lastmod": "2023-10-26 20:38:41", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Tinetti-G", "name": { "family": "Tinetti", "given": "Giovanna" } }, { "id": "Vidal-Madjar-A", "name": { "family": "Vidal-Madjar", "given": "Alfred" } }, { "id": "Liang-Mao-Chang", "name": { "family": "Liang", "given": "Mao-Chang" }, "orcid": "0000-0002-5294-9344" }, { "id": "Beaulieu-J-P", "name": { "family": "Beaulieu", "given": "Jean-Philippe" }, "orcid": "0000-0003-0014-3354" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Carey-S-J", "name": { "family": "Carey", "given": "Sean" }, "orcid": "0000-0002-0221-6871" }, { "id": "Barber-R-J", "name": { "family": "Barber", "given": "Robert J." } }, { "id": "Tennyson-J", "name": { "family": "Tennyson", "given": "Jonathan" } }, { "id": "Ribas-I", "name": { "family": "Ribas", "given": "Ignasi" } }, { "id": "Allard-N", "name": { "family": "Allard", "given": "Nicole" } }, { "id": "Ballester-G-E", "name": { "family": "Ballester", "given": "Gilda E." } }, { "id": "Sing-D-K", "name": { "family": "Sing", "given": "David K." } }, { "id": "Selsis-F", "name": { "family": "Selsis", "given": "Franck" }, "orcid": "0000-0001-9619-5356" } ] }, "title": "Water vapour in the atmosphere of a transiting extrasolar planet", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2007 Nature Publishing Group.\n\nReceived 8 April; accepted 1 June 2007.\n\nWe thank A. Lecavelier, D. Ehrenreich, J.-M. D\u00e9sert,\nRoger Ferlet and G. Hebrard for their work on the IRAC observations. We thank A. Noriega-Crespo and the Spitzer Staff for helping to schedule the observations with IRAC, and E. Lellouch, A. Morbidelli, B. Schultz, F. Bouchy and J. B. Marquette for useful input to the paper. M.-C.L. and Y.Y. were supported by NASA and the Virtual Planetary Laboratory at the California Institute of Technology.\n\nSubmitted - 0707.3064.pdf
", "abstract": "Water is predicted to be among the most abundant (if not the most abundant) molecular species after hydrogen in the atmospheres of close-in extrasolar giant planets ('hot Jupiters'). Several attempts have been made to detect water on such planets, but have either failed to find compelling evidence for it or led to claims that should be taken with caution. Here we report an analysis of recent observations of the hot Jupiter HD 189733b (ref. 6) taken during the transit, when the planet passed in front of its parent star. We find that absorption by water vapour is the most likely cause of the wavelength-dependent variations in the effective radius of the planet at the infrared wavelengths 3.6 \u00b5m, 5.8 \u00b5m (both ref. 7) and 8 \u00b5m (ref. 8). The larger effective radius observed at visible wavelengths^9 may arise from either stellar variability or the presence of clouds/hazes. We explain the report of a non-detection of water on HD 189733b (ref. 4) as being a consequence of the nearly isothermal vertical profile of the planet's atmosphere.", "date": "2007-07-12", "date_type": "published", "publication": "Nature", "volume": "448", "number": "7150", "publisher": "Nature Publishing Group", "pagerange": "169-171", "id_number": "CaltechAUTHORS:20140724-161026901", "issn": "0028-0836", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140724-161026901", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA" }, { "agency": "Virtual Planetary Laboratory, Caltech" } ] }, "local_group": { "items": [ { "id": "Infrared-Processing-and-Analysis-Center-(IPAC)" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1038/nature06002", "primary_object": { "basename": "0707.3064.pdf", "url": "https://authors.library.caltech.edu/records/8d5br-9vc94/files/0707.3064.pdf" }, "resource_type": "article", "pub_year": "2007", "author_list": "Tinetti, Giovanna; Vidal-Madjar, Alfred; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/exkke-q9223", "eprint_id": 8856, "eprint_status": "archive", "datestamp": "2023-08-22 09:23:12", "lastmod": "2023-10-16 21:46:33", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Jiang-Xun", "name": { "family": "Jiang", "given": "Xun" }, "orcid": "0000-0001-8932-3807" }, { "id": "Eichelberger-S-J", "name": { "family": "Eichelberger", "given": "Scott J." } }, { "id": "Hartmann-D-L", "name": { "family": "Hartmann", "given": "Dennis L." }, "orcid": "0000-0002-4495-7774" }, { "id": "Shia-Run-Lie", "name": { "family": "Shia", "given": "Runlie" }, "orcid": "0000-0003-1911-3120" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Influence of Doubled CO2 on Ozone via Changes in the Brewer\u2013Dobson Circulation", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2007 American Meteorological Society. \n\nManuscript received 8 February 2006, in final form 7 November 2006. \n\nThis work was supported by NASA Grant NNG04GD76G to the California Institute of Technology, and by the Climate Dynamics Program of the National Science Foundation under Grant ATM-0409075 to the University of Washington.", "abstract": "In this short note, the effect of enhanced circulation due to doubling CO2 on ozone is investigated. The difference of Brewer\u2013Dobson circulation (BDC) between the doubled CO2 and control run from an idealized atmospheric general circulation model is added to the BDC climatology derived from National Centers for Environmental Prediction\u2014Department of Energy Reanalysis 2 (NCEP2) from 1979 to 2002. Then it is used to drive the California Institute of Technology/Jet Propulsion Laboratory (Caltech/JPL) two-dimensional chemistry and transport model. The results reveal that the total ozone increases by 7 and 3.5 Dobson units (DU) in the high latitudes of the Northern and Southern Hemispheres, respectively, and decreases by 4 DU in the Tropics as a result of the increase in BDC associated with doubled CO2. If the change of eddy mixing coefficients after doubling CO2 is also considered, the total ozone will increase by 6.5 and 3 DU in the high latitudes of the Northern and Southern Hemispheres after combining both effects from the change in BDC and eddy mixing coefficients.", "date": "2007-07", "date_type": "published", "publication": "Journal of the Atmospheric Sciences", "volume": "64", "number": "7", "publisher": "American Meteorological Society", "pagerange": "2751-2755", "id_number": "CaltechAUTHORS:JIAjas07", "issn": "0022-4928", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:JIAjas07", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1175/JAS3969.1", "primary_object": { "basename": "JIAjas07.pdf", "url": "https://authors.library.caltech.edu/records/exkke-q9223/files/JIAjas07.pdf" }, "resource_type": "article", "pub_year": "2007", "author_list": "Jiang, Xun; Eichelberger, Scott J.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/ad9a0-vsn35", "eprint_id": 20435, "eprint_status": "archive", "datestamp": "2023-08-22 09:16:48", "lastmod": "2023-10-20 22:56:24", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Liang-Mao-Chang", "name": { "family": "Liang", "given": "Mao-Chang" }, "orcid": "0000-0002-5294-9344" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Shemansky-D-E", "name": { "family": "Shemansky", "given": "Donald E." }, "orcid": "0000-0001-7168-871X" } ] }, "title": "Photolytically Generated Aerosols in the Mesosphere and Thermosphere of Titan", "ispublished": "pub", "full_text_status": "public", "keywords": "atmospheric effects; methods : data analysis; methods : numerical; planetary systems; planets and satellites : individual (Titan); radiative transfer", "note": "\u00a9 2007 The American Astronomical Society. \n\nReceived 2006 November 20; accepted 2007 April 11; published 2007 May 8. \n\nThis research was supported by NASA grant NNG06GF33G and Cassini grant JPL.1256000 to the California Institute of Technology. D. E. S. acknowledges support from NASA grant NNG06GH76G and from Cassini UVIS Program contract 1531660 to Space Environment Technologies.\n\nPublished - LIAapjl07a.pdf
Accepted Version - 0705.0145.pdf
", "abstract": "Analysis of the Cassini Ultraviolet Imaging Spectrograph (UVIS) stellar and solar occultations at Titan to date include 12 species: N_2 (nitrogen), CH_4 (methane), C_2H_2 (acetylene), C_2H_4 (ethylene), C_2H_6 (ethane), C_4H_2 (diacetylene), C_6H_6 (benzene), C_6N_2 (dicyanodiacetylene), C_2N_2 (cyanogen), HCN (hydrogen cyanide), HC_3N (cyanoacetylene), and aerosols distinguished by a structureless continuum extinction (absorption plus scattering) of photons in the EUV. The introduction of aerosol particles, retaining the same refractive index properties as tholin with radius ~125 \u00c5 and using Mie theory, provides a satisfactory fit to the spectra. The derived vertical profile of aerosol density shows distinct structure, implying a reactive generation process reaching altitudes more than 1000 km above the surface. A photochemical model presented here provides a reference basis for examining the chemical and physical processes leading to the distinctive atmospheric opacity at Titan. We find that dicyanodiacetylene is condensable at ~650 km, where the atmospheric temperature minimum is located. This species is the simplest molecule identified to be condensable. Observations are needed to confirm the existence and production rates of dicyanodiacetylene.", "date": "2007-06-01", "date_type": "published", "publication": "Astrophysical Journal", "volume": "661", "number": "2", "publisher": "American Astronomical Society", "pagerange": "L199-L202", "id_number": "CaltechAUTHORS:20101015-094041133", "issn": "0004-637X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20101015-094041133", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NNG06GF33G" }, { "agency": "JPL", "grant_number": "JPL.1256000" }, { "agency": "NASA", "grant_number": "NNG06GH76G" }, { "agency": "NASA", "grant_number": "1531660" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1086/518785", "primary_object": { "basename": "0705.0145.pdf", "url": "https://authors.library.caltech.edu/records/ad9a0-vsn35/files/0705.0145.pdf" }, "related_objects": [ { "basename": "LIAapjl07a.pdf", "url": "https://authors.library.caltech.edu/records/ad9a0-vsn35/files/LIAapjl07a.pdf" } ], "resource_type": "article", "pub_year": "2007", "author_list": "Liang, Mao-Chang; Yung, Yuk L.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/1yhhw-00215", "eprint_id": 52939, "eprint_status": "archive", "datestamp": "2023-08-22 09:14:10", "lastmod": "2023-10-18 21:47:42", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Tinetti-G", "name": { "family": "Tinetti", "given": "Giovanna" } }, { "id": "Cornia-A", "name": { "family": "Cornia", "given": "Alberto" } }, { "id": "Liang-Mao-Chang", "name": { "family": "Liang", "given": "Mao-Chang" }, "orcid": "0000-0002-5294-9344" }, { "id": "Boccaletti-A", "name": { "family": "Boccaletti", "given": "Anthony" }, "orcid": "0000-0001-9353-2724" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Spectral signatures from super-Earths, warm and hot-Neptunes", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2007 Mary Ann Liebert, Inc.\n\nPublished - Yung_2007p496.pdf
", "abstract": "ESA's and NASA's planet characterization missions, will allow us to explore the diversity\nof planets around stars of different spectral type, and will expand the existing field of\ncomparative planetology beyond our Solar System. In particular, terrestrial planets\ngreater than one Earth mass are not represented in our Solar System, but may occur in\nothers (Beaulieu et al., 2006; Rivera et al. 2005). The next generation of space telescopes,\nthe James Webb Space Telescope (2013), will have the capability of acquiring\ntransmission and emission spectra in the infrared of these extrasolar worlds. Further into\nthe future, the direct imaging of exoplanets, both in the optical and infrared, will extend\nour understanding to extrasolar bodies orbiting few Astronomical Units from their parent\nstar and expand our knowledge to smaller-size objects.", "date": "2007-06", "date_type": "published", "publication": "Astrobiology", "volume": "7", "number": "3", "publisher": "Mary Ann Liebert", "pagerange": "496-497", "id_number": "CaltechAUTHORS:20141217-092004536", "issn": "1531-1074", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20141217-092004536", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1089/ast.2007.1016", "primary_object": { "basename": "Yung_2007p496.pdf", "url": "https://authors.library.caltech.edu/records/1yhhw-00215/files/Yung_2007p496.pdf" }, "resource_type": "article", "pub_year": "2007", "author_list": "Tinetti, Giovanna; Cornia, Alberto; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/v4gbr-jw839", "eprint_id": 46637, "eprint_status": "archive", "datestamp": "2023-08-22 09:07:12", "lastmod": "2023-10-26 19:53:44", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Miller-C-E", "name": { "family": "Miller", "given": "C. E." }, "orcid": "0000-0002-9380-4838" }, { "id": "Crisp-D", "name": { "family": "Crisp", "given": "D." }, "orcid": "0000-0002-4573-9998" }, { "id": "Boesch-H", "name": { "family": "Boesch", "given": "H." }, "orcid": "0000-0003-3944-9879" }, { "id": "Salawitch-R-J", "name": { "family": "Salawitch", "given": "R. J." } }, { "id": "Sander-S-P", "name": { "family": "Sander", "given": "S. P." }, "orcid": "0000-0003-1424-3620" }, { "id": "Sen-B", "name": { "family": "Sen", "given": "B." } }, { "id": "Toon-G-C", "name": { "family": "Toon", "given": "G. C." }, "orcid": "0000-0003-4174-7541" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Y. L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Precision requirements for space-based X_(CO_2) data", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2007 American Geophysical Union. \n\nReceived 15 June 2006; revised 16 September 2006; accepted 11 January 2007; article first published online 26 May 2007. \n\nThis work was supported by the Orbiting Carbon Observatory (OCO) project through NASA's Earth System Science Pathfinder (ESSP) program. SCO and JTR were supported by a NASA IDS grant (NAG5-9462) to JTR. We thank R. Frey for the assistance with the MODIS cloud data.\nPlease note: Wiley Blackwell is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.\n\nPublished - jgrd13304.pdf
Supplemental Material - jgrd13304-sup-0001-t01.txt
Supplemental Material - jgrd13304-sup-0002-t02.txt
", "abstract": "Precision requirements are determined for space-based column-averaged CO_2 dry air mole fraction (X_(CO)_2) data. These requirements result from an assessment of spatial and temporal gradients in (X_(CO)_2) the relationship between (X_(CO)_2) precision and surface CO_2 flux uncertainties inferred from inversions of the (X_(CO)_2) data, and the effects of (X_(CO)_2) biases on the fidelity of CO_2 flux inversions. Observational system simulation experiments and synthesis inversion modeling demonstrate that the Orbiting Carbon Observatory mission design and sampling strategy provide the means to achieve these (X_(CO)_2) data precision requirements.", "date": "2007-05-27", "date_type": "published", "publication": "Journal of Geophysical Research D", "volume": "112", "number": "D10", "publisher": "American Geophysical Union", "pagerange": "Art. No. D10314", "id_number": "CaltechAUTHORS:20140702-113242262", "issn": "0148-0227", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140702-113242262", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NAG5-9462" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2006JD007659", "primary_object": { "basename": "jgrd13304.pdf", "url": "https://authors.library.caltech.edu/records/v4gbr-jw839/files/jgrd13304.pdf" }, "related_objects": [ { "basename": "jgrd13304-sup-0001-t01.txt", "url": "https://authors.library.caltech.edu/records/v4gbr-jw839/files/jgrd13304-sup-0001-t01.txt" }, { "basename": "jgrd13304-sup-0002-t02.txt", "url": "https://authors.library.caltech.edu/records/v4gbr-jw839/files/jgrd13304-sup-0002-t02.txt" } ], "resource_type": "article", "pub_year": "2007", "author_list": "Miller, C. E.; Crisp, D.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/1wbdw-4zh72", "eprint_id": 48892, "eprint_status": "archive", "datestamp": "2023-08-22 08:49:00", "lastmod": "2023-10-17 20:31:06", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Tian-Baijun", "name": { "family": "Tian", "given": "B." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Y. L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Waliser-D-E", "name": { "family": "Waliser", "given": "D. E." } }, { "id": "Tyranowski-T", "name": { "family": "Tyranowski", "given": "T." } }, { "id": "Kuai-Le", "name": { "family": "Kuai", "given": "L." }, "orcid": "0000-0001-6406-1150" }, { "id": "Fetzer-E-J", "name": { "family": "Fetzer", "given": "E. J." } }, { "id": "Irion-F-W", "name": { "family": "Irion", "given": "F. W." } } ] }, "title": "Intraseasonal variations of the tropical total ozone and their connection to the Madden-Julian Oscillation", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2007 The American Geophysical Union.\n\nReceived 23 January 2007; Revised 23 February 2007; Accepted 16 March 2007; Published 21 April 2007.\n\nThis research was carried out at the JPL, Caltech, under a contract with NASA. It was jointly supported by the Research and Technology Development program, Human Resources Development fund, and the AIRS project at JPL. YLY and LK were supported by NASA grant NNG04GD76G to Caltech and TT acknowledged support by the Caltech SURF program in 2006. We thank S. Frith for sending us the\ndaily TOMS/SBUV MOD data, R. Stolarski and X. Jiang for discussions and G. Kiladis for comments. The AIRS O3, CMAP rainfall, and NCEP reanalysis data are provided by NASA/GSFC/DAAC, NOAA/CPC, and NOAA/OAR/ESRL PSD from their web sites.\n\nPublished - grl22975.pdf
Supplemental Material - grl22975-sup-0001-readme.txt
Supplemental Material - grl22975-sup-0002-fs01.tiff
", "abstract": "We investigate the intraseasonal (30\u201390 day) variations in satellite-observed tropical total ozone (O_3) and their connection to the Madden-Julian Oscillation (MJO). Tropical total O_3 intraseasonal variations are large (\u223c\u00b110 DU) and comparable to those in annual and interannual time scales. These O_3 anomalies are mainly evident in the subtropics over the Pacific and eastern; hemisphere and propagate slowly eastward (\u223c5 m s^(\u22121)). The subtropical negative (positive) O_3 anomalies are typically collocated with the subtropical upper troposphere anticyclones (cyclones) generated by equatorial MJO convection and flank or lie to the west of the equatorial enhanced (suppressed) MJO convection. The subtropical O_3 are anti-correlated with geopotential height anomalies near the tropopause and thus mainly associated with the O_3 variability in the stratosphere rather the troposphere. Over the equatorial regions, total O_3 anomalies are small.", "date": "2007-04", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "34", "number": "8", "publisher": "American Geophysical Union", "pagerange": "Art. No. L08704", "id_number": "CaltechAUTHORS:20140826-085126532", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140826-085126532", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA/JPL/Caltech" }, { "agency": "NASA", "grant_number": "NNG04GD76G" }, { "agency": "Caltech Summer Undergraduate Research Fellowship (SURF)" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2007GL029451", "primary_object": { "basename": "grl22975-sup-0002-fs01.tiff", "url": "https://authors.library.caltech.edu/records/1wbdw-4zh72/files/grl22975-sup-0002-fs01.tiff" }, "related_objects": [ { "basename": "grl22975.pdf", "url": "https://authors.library.caltech.edu/records/1wbdw-4zh72/files/grl22975.pdf" }, { "basename": "grl22975-sup-0001-readme.txt", "url": "https://authors.library.caltech.edu/records/1wbdw-4zh72/files/grl22975-sup-0001-readme.txt" } ], "resource_type": "article", "pub_year": "2007", "author_list": "Tian, B.; Yung, Y. L.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/wmvvf-mfm26", "eprint_id": 48955, "eprint_status": "archive", "datestamp": "2023-08-22 08:42:28", "lastmod": "2023-10-17 20:34:12", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Liang-Mao-Chang", "name": { "family": "Liang", "given": "Mao-Chang" }, "orcid": "0000-0002-5294-9344" }, { "id": "Cheng-Bing-Ming", "name": { "family": "Cheng", "given": "Bing-Ming" } }, { "id": "Lu-Hsiao-Chi", "name": { "family": "Lu", "given": "Hsiao-Chi" } }, { "id": "Chen-Hong-Kai", "name": { "family": "Chen", "given": "Hong-Kai" } }, { "id": "Alam-M-S", "name": { "family": "Alam", "given": "M. S." } }, { "id": "Lee-Yuan-Pern", "name": { "family": "Lee", "given": "Yuan-Pern" } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Isotopic Fractionation of Nitrogen in Ammonia in the Troposphere of Jupiter", "ispublished": "pub", "full_text_status": "public", "keywords": "atmospheric effects; planetary systems; planets and satellites: individual (Jupiter); radiative transfer", "note": "\u00a9 2007 American Astronomical Society. Received 2006 November 11; accepted 2007 January 29; published 2007 February 21. We thank Geoff Blake and John Eiler for helpful discussion,\nand Andy Ackerman, Xin Guo, Run-Lie Shia, and Giovanna\nTinetti for assisting the CARMA simulation, and Chris Parkinson for useful comments. Special thanks are due the referee Emmanuel Lellouch for his insightful comments. This work was supported by NASA grant NNG06GF33G to the California\nInstitute of Technology. B.-M. C. was supported by the National Science Council of Taiwan (grant NSC95-2113-M-213-006).\n\nPublished - 1538-4357_657_2_L117.pdf
", "abstract": "Laboratory measurements of the photoabsorption cross section of ^(15)NH_3 at wavelengths between 140 and 220 nm are presented for the first time. Incorporating the measured photoabsorption cross sections of ^(15)NH_3 and ^(14)NH_3 into a one-dimensional photochemical diffusive model, we find that at 400 mbar, the photolytic efficiency of ^(15)NH_3 is about 38% greater than that of ^(14)NH_3. In addition, it is known that ammonia can condense in the region between 200 and 700 mbar, and the condensation tends to deplete the abundance ratio of ^(15)NH_3 and ^(14)NH_3. By matching the observed ratio of ^(15)NH_3 and ^(14)NH_3 at 400 mbar, the combined effect of photolysis and microphysics produces the ratio of (2.42 \u00b1 0.34) \u00d7 10^(-3) in the deep atmosphere, in excellent agreement with the Galileo spacecraft measurements. The usefulness of the isotopic composition of ammonia as a tracer of chemical and dynamical processes in the troposphere of Jupiter is discussed.", "date": "2007-03-10", "date_type": "published", "publication": "Astrophysical Journal Letters", "volume": "657", "number": "2", "publisher": "American Astronomical Society", "pagerange": "L117-L120", "id_number": "CaltechAUTHORS:20140827-074544196", "issn": "2041-8205", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140827-074544196", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NNG06GF33G" }, { "agency": "National Science Council of Taiwan", "grant_number": "NSC95-2113-M-213-006" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1086/513192", "primary_object": { "basename": "1538-4357_657_2_L117.pdf", "url": "https://authors.library.caltech.edu/records/wmvvf-mfm26/files/1538-4357_657_2_L117.pdf" }, "resource_type": "article", "pub_year": "2007", "author_list": "Liang, Mao-Chang; Cheng, Bing-Ming; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/ycjvt-yg738", "eprint_id": 48886, "eprint_status": "archive", "datestamp": "2023-08-22 08:39:14", "lastmod": "2023-10-17 20:30:47", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Jiang-Xun", "name": { "family": "Jiang", "given": "Xun" }, "orcid": "0000-0001-8932-3807" }, { "id": "Ku-Wai-Lim", "name": { "family": "Ku", "given": "Wai Lim" } }, { "id": "Shia-Run-Lie", "name": { "family": "Shia", "given": "Run-Lie" }, "orcid": "0000-0003-1911-3120" }, { "id": "Li-Qinbin", "name": { "family": "Li", "given": "Qinbin" } }, { "id": "Elkins-J-W", "name": { "family": "Elkins", "given": "James W." } }, { "id": "Prinn-R-G", "name": { "family": "Prinn", "given": "Ronald G." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Seasonal cycle of N_2O: Analysis of data", "ispublished": "pub", "full_text_status": "public", "keywords": "N2O seasonal cycle; multitaper method; surface sources", "note": "\u00a9 2007 by the American Geophysical Union.\n\nReceived 13 January 2006; revised 22 August 2006; accepted 18 September 2006; published 26 January 2007.\n\nWe thank T. Liao for the helpful discussions and two anonymous reviewers for helpful comments. We also want to acknowledge J. H. Butler, G. S. Dutton, and T. M. Thompson for providing their individual data sets from NOAA. We would like to acknowledge our colleagues from the AGAGE network for providing their in situ sampling data through the web and for collecting NOAA flasks at their stations (CGO, MHD). This research was supported in part by NSF grant ATM-9903790. Yuk L. Yung acknowledges support by the Davidow Fund.\n\nPublished - gbc1342.pdf
Supplemental Material - gbc1342-sup-0001-t01.txt
Supplemental Material - gbc1342-sup-0002-t02.txt
Supplemental Material - gbc1342-sup-0003-t03.txt
Supplemental Material - gbc1342-sup-0004-t04.txt
", "abstract": "We carried out a systematic study of the seasonal cycle and its latitudinal variation in the nitrous oxide (N_2O) data collected by National Oceanic and Atmospheric Administration\u2013Global Monitoring Division (NOAA-GMD) and the Advanced Global Atmospheric Gases Experiment (AGAGE). In order to confirm the weak seasonal signal in the observations, we applied the multitaper method for the spectrum analysis and studied the stations with significant seasonal cycle. In addition, the measurement errors must be small compared with the seasonal cycle. The N_2O seasonal cycles from seven stations satisfied these criteria and were analyzed in detail. The stations are Alert (82\u00b0N, 62\u00b0W), Barrow (71\u00b0N, 157\u00b0W), Mace Head (53\u00b0N, 10\u00b0W), Cape Kumukahi (19\u00b0N, 155\u00b0W), Cape Matatula (14\u00b0S, 171\u00b0W), Cape Grim (41\u00b0S, 145\u00b0E) and South Pole (90\u00b0S, 102\u00b0W). The amplitude (peak to peak) of the seasonal cycle of N_2O varies from 0.29 ppb (parts-per-billion by mole fraction in dry air) at the South Pole to 1.15 ppb at Alert. The month at which the seasonal cycle is at a minimum varies monotonically from April (South Pole) to September (Alert). The seasonal cycle in the Northern Hemisphere shows the influence of the stratosphere; the seasonal cycle of N_2O in the Southern Hemisphere suggests greater influence from surface sources. Preliminary estimates are obtained for the magnitude of the seasonally varying sources needed to account for the observations.", "date": "2007-03", "date_type": "published", "publication": "Global Biogeochemical Cycles", "volume": "21", "number": "1", "publisher": "American Geophysical Union", "pagerange": "Art. No. GB1006", "id_number": "CaltechAUTHORS:20140826-084540883", "issn": "0886-6236", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140826-084540883", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "ATM- 9903790" }, { "agency": "Davidow Fund" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2006GB002691", "primary_object": { "basename": "gbc1342-sup-0002-t02.txt", "url": "https://authors.library.caltech.edu/records/ycjvt-yg738/files/gbc1342-sup-0002-t02.txt" }, "related_objects": [ { "basename": "gbc1342-sup-0003-t03.txt", "url": "https://authors.library.caltech.edu/records/ycjvt-yg738/files/gbc1342-sup-0003-t03.txt" }, { "basename": "gbc1342-sup-0004-t04.txt", "url": "https://authors.library.caltech.edu/records/ycjvt-yg738/files/gbc1342-sup-0004-t04.txt" }, { "basename": "gbc1342.pdf", "url": "https://authors.library.caltech.edu/records/ycjvt-yg738/files/gbc1342.pdf" }, { "basename": "gbc1342-sup-0001-t01.txt", "url": "https://authors.library.caltech.edu/records/ycjvt-yg738/files/gbc1342-sup-0001-t01.txt" } ], "resource_type": "article", "pub_year": "2007", "author_list": "Jiang, Xun; Ku, Wai Lim; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/p2p41-zfn35", "eprint_id": 7778, "eprint_status": "archive", "datestamp": "2023-08-22 08:17:47", "lastmod": "2023-10-16 21:05:37", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Parkinson-C-D", "name": { "family": "Parkinson", "given": "C. D." }, "orcid": "0000-0002-5722-2224" }, { "id": "Liang-Mao-Chang", "name": { "family": "Liang", "given": "M. C." }, "orcid": "0000-0002-5294-9344" }, { "id": "Hartman-C-J", "name": { "family": "Hartman", "given": "H." } }, { "id": "Hansen-C-J", "name": { "family": "Hansen", "given": "C. J." } }, { "id": "Tinetti-G", "name": { "family": "Tinetti", "given": "G." } }, { "id": "Meadows-V", "name": { "family": "Meadows", "given": "V." } }, { "id": "Kirschvink-J-L", "name": { "family": "Kirschvink", "given": "J. L." }, "orcid": "0000-0001-9486-6689" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Y. L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Enceladus: Cassini observations and implications for the search for life", "ispublished": "pub", "full_text_status": "public", "keywords": "astrobiology -- planets and satellites: general -- planets and satellites: formation -- planets and satellites: individual: Saturn -- planets and satellites: individual: Enceladus -- solar system: general -- astrochemistry", "note": "\u00a9 ESO 2007. \n\nReceived 7 June 2006 / Accepted 27 September 2006. \n\nWe thank Xun Jiang for assistance with linear regression, Andy Ingersoll, G. Orzechowska, and David Stevenson for helpful discussions. We thank F. Tian for communication of results prior to publication. We thank R. West for helpful comments and D. Shemansky for sharing the photoabsorption cross-sections of HCN. This work was supported by NASA grant NASA5-13296 to California Institute of Technology. The research at the Jet Propulsion Laboratory (JPL), California Institute of Technology, was performed under contract with the National Aeronautics and Space Administration.", "abstract": "Aims. The recent Cassini discovery of water vapor plumes ejected from the south pole of the Saturnian satellite, Enceladus, presents a unique window of opportunity for the detection of extant life in our solar system. \n\nMethods. With its significant geothermal energy source propelling these plumes >80 km from the surface of the moon and the ensuing large temperature gradient with the surrounding environment, it is possible to have the weathering of rocks by liquid water at the rock/liquid interface. For the cases of the putatively detected salt-water oceans beneath the ice crusts of Europa and Callisto, an isolated subsurface ocean without photosynthesis or contact with an oxidizing atmosphere will approach chemical equilibrium and annihilate any ecosystems dependent on redox gradients unless there is a substantial alternative energy source. This thermodynamic tendency imposes severe constraints on any biota that is based on chemical energy. On Enceladus, the weathering of rocks by liquid water and any concomitant radioactive emissions are possible incipient conditions for life. If there is CO, CO2 and NH3 present in the spectra obtained from the plume, then this is possible evidence that amino acids could be formed at the rock/liquid interface of Enceladus. The combination of a hydrological cycle, chemical redox gradient and geochemical cycle give favorable conditions for life. \n\nResults. We discuss the search for signatures of these species and organics in the Cassini UVIS spectra of the plume and implications for the possible detection of life.", "date": "2007-02", "date_type": "published", "publication": "Astronomy and Astrophysics", "volume": "463", "number": "1", "publisher": "EDP Sciences", "pagerange": "353-357", "id_number": "CaltechAUTHORS:PARaanda07", "issn": "0004-6361", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:PARaanda07", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1051/0004-6361:20065773", "primary_object": { "basename": "PARaanda07.pdf", "url": "https://authors.library.caltech.edu/records/p2p41-zfn35/files/PARaanda07.pdf" }, "resource_type": "article", "pub_year": "2007", "author_list": "Parkinson, C. D.; Liang, M. C.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/8vnas-phm34", "eprint_id": 7062, "eprint_status": "archive", "datestamp": "2023-08-22 08:05:26", "lastmod": "2023-10-16 20:41:28", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Liang-Mao-Chang", "name": { "family": "Liang", "given": "Mao-Chang" }, "orcid": "0000-0002-5294-9344" }, { "id": "Blake-G-A", "name": { "family": "Blake", "given": "Geoffrey A." }, "orcid": "0000-0003-0787-1610" }, { "id": "Lewis-B-R", "name": { "family": "Lewis", "given": "Brenton R." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Oxygen isotopic composition of carbon dioxide in the middle atmosphere", "ispublished": "pub", "full_text_status": "public", "keywords": "biogeochemical cycles; CO2; mesosphere; stratosphere", "note": "\u00a9 2007 by The National Academy of Sciences of the USA. Freely available online through the PNAS open access option. \n\nCommunicated by Inez Y. Fung, University of California, Berkeley, CA, November 10, 2006 (received for review January 31, 2006). Published online before print December 26, 2006, 10.1073/pnas.0610009104 \n\nWe give special thanks to G.R. Gladstone for the solar Lyman-\u03b1 flux and S.T. Gibson for providing his coupled-channel code. We also thank B.C. Hsieh, X. Jiang, and R.L. Shia for helping us with the model; M. Gerstell, H. Hartman, A. Ingersoll, J. Kaiser, C. Miller, H. Pickett, T. R\u00f6ckmann, and all of the members in our group for their helpful comments; and Inez Fung for handling the reviewing process and two anonymous referees for their insightful comments to improve the manuscript. This work was supported by National Science Foundation Grant ATM-0529268. \n\nAuthor contributions: M.-C.L., G.A.B., and Y.L.Y. designed research; M.-C.L. and B.R.L. performed research; and M.-C.L., G.A.B., B.R.L., and Y.L.Y. wrote the paper. \n\nThe authors declare no conflict of interest.\n\nPublished - LIApnas07a.pdf
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", "abstract": "The isotopic composition of long-lived trace molecules provides a window into atmospheric transport and chemistry. Carbon dioxide is a particularly powerful tracer, because its abundance remains >100 parts per million by volume (ppmv) in the mesosphere. Here, we successfully reproduce the isotopic composition of CO2 in the middle atmosphere, which has not been previously reported. The mass-independent fractionation of oxygen in CO2 can be satisfactorily explained by the exchange reaction with O(1D). In the stratosphere, the major source of O(1D) is O3 photolysis. Higher in the mesosphere, we discover that the photolysis of 16O17O and 16O18O by solar Lyman-{alpha} radiation yields O(1D) 10\u2013100 times more enriched in 17O and 18O than that from ozone photodissociation at lower altitudes. This latter source of heavy O(1D) has not been considered in atmospheric simulations, yet it may potentially affect the \"anomalous\" oxygen signature in tropospheric CO2 that should reflect the gross carbon fluxes between the atmosphere and terrestrial biosphere. Additional laboratory and atmospheric measurements are therefore proposed to test our model and validate the use of CO2 isotopic fractionation as a tracer of atmospheric chemical and dynamical processes.", "date": "2007-01-02", "date_type": "published", "publication": "Proceedings of the National Academy of Sciences of the United States of America", "volume": "104", "number": "1", "publisher": "National Academy of Sciences", "pagerange": "21-25", "id_number": "CaltechAUTHORS:LIApnas07a", "issn": "0027-8424", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:LIApnas07a", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1073/pnas.0610009104", "pmcid": "PMC1749325", "primary_object": { "basename": "LIApnas07afig4.jpeg", "url": "https://authors.library.caltech.edu/records/8vnas-phm34/files/LIApnas07afig4.jpeg" }, "related_objects": [ { "basename": "LIApnas07afig5.jpeg", "url": "https://authors.library.caltech.edu/records/8vnas-phm34/files/LIApnas07afig5.jpeg" }, { "basename": "LIApnas07a.pdf", "url": "https://authors.library.caltech.edu/records/8vnas-phm34/files/LIApnas07a.pdf" }, { "basename": "LIApnas07afig1.jpg", "url": "https://authors.library.caltech.edu/records/8vnas-phm34/files/LIApnas07afig1.jpg" }, { "basename": "LIApnas07afig6.jpeg", "url": "https://authors.library.caltech.edu/records/8vnas-phm34/files/LIApnas07afig6.jpeg" }, { "basename": "medium.png", "url": "https://authors.library.caltech.edu/records/8vnas-phm34/files/medium.png" }, { "basename": "small.png", "url": "https://authors.library.caltech.edu/records/8vnas-phm34/files/small.png" }, { "basename": "LIApnas07afig2.jpeg", "url": "https://authors.library.caltech.edu/records/8vnas-phm34/files/LIApnas07afig2.jpeg" }, { "basename": "LIApnas07afig3.jpeg", "url": "https://authors.library.caltech.edu/records/8vnas-phm34/files/LIApnas07afig3.jpeg" } ], "resource_type": "article", "pub_year": "2007", "author_list": "Liang, Mao-Chang; Blake, Geoffrey A.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/k56td-pnw74", "eprint_id": 16867, "eprint_status": "archive", "datestamp": "2023-08-22 08:04:47", "lastmod": "2023-10-19 22:37:18", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Tinetti-G", "name": { "family": "Tinetti", "given": "Giovanna" } }, { "id": "Liang-Mao-Chang", "name": { "family": "Liang", "given": "Mao-Chang" }, "orcid": "0000-0002-5294-9344" }, { "id": "Vidal-Madjar-A", "name": { "family": "Vidal-Madjar", "given": "Alfred" } }, { "id": "Ehrenreich-D", "name": { "family": "Ehrenreich", "given": "David" }, "orcid": "0000-0001-9704-5405" }, { "id": "Lecavelier-des-Etangs-A", "name": { "family": "Lecavelier des Etangs", "given": "Alain" }, "orcid": "0000-0002-5637-5253" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Infrared Transmission Spectra for Extrasolar Giant Planets", "ispublished": "pub", "full_text_status": "public", "keywords": "atmospheric effects; occultations; radiative transfer; techniques: spectroscopic", "note": "\u00a9 2007 American Astronomical Society.\n\nPrint publication: Issue 1 (2007 January 1); received 2006 August 9; accepted for publication 2006 November 8; published 2006 December 14.\n\nWe would like to thank the anonymous referee for his help\nto improve the Letter, L. S. Rothman for having provided the\nHITEMP data list, and R. Ferlet, J. M. De\u00b4sert, F. Bouchy, G. He\u00b4brard, C. D. Parkinson, A. Noriega-Crespo, and S. Carey, for their valuable inputs. G. T. is currently supported by the European Space Agency, and M.-C. L. and Y. L. Y. by NASA grant NASA5-13296 to Caltech.\n\nPublished - TINapjl07.pdf
", "abstract": "Among the hot Jupiters known to date that transit their parent stars, the two best candidates to be observed with transmission spectroscopy in the mid-infrared (MIR) are HD 189733b and HD 209458b, due to their combined characteristics of planetary density, orbital parameters, and parent star distance and brightness. Here we simulate transmission spectra of these two planets during their primary transit in the MIR, and we present sensitivity studies of the spectra to the changes of atmospheric thermal properties, molecular abundances, and C/O ratios. Our model predicts that the dominant species absorbing in the MIR on hot Jupiters are water vapor and carbon monoxide, and their relative abundances are determined by the C/O ratio. Since the temperature profile plays a secondary role in the transmission spectra of hot Jupiters compared to molecular abundances, future primary transit observations in the MIR of those objects might offer insight on extrasolar giant planet atmospheric chemistry. We find here that the absorption features caused by water vapor and carbon monoxide in a cloud-free atmosphere are deep enough to be observable by the present and future generation of space-based observatories, such as Spitzer Space Telescope and James Webb Space Telescope. We discuss our results in light of the capabilities of these telescopes.", "date": "2007-01-01", "date_type": "published", "publication": "Astrophysical Journal Letters", "volume": "654", "number": "1", "publisher": "American Astronomical Society", "pagerange": "L99-L102", "id_number": "CaltechAUTHORS:20091203-110658021", "issn": "2041-8205", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20091203-110658021", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "European Space Agency (ESA)" }, { "agency": "NASA", "grant_number": "NASA5-13296" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1086/510716", "primary_object": { "basename": "TINapjl07.pdf", "url": "https://authors.library.caltech.edu/records/k56td-pnw74/files/TINapjl07.pdf" }, "resource_type": "article", "pub_year": "2007", "author_list": "Tinetti, Giovanna; Liang, Mao-Chang; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/tzy21-em590", "eprint_id": 48895, "eprint_status": "archive", "datestamp": "2023-08-22 08:02:18", "lastmod": "2023-10-17 20:31:17", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Natraj-V", "name": { "family": "Natraj", "given": "Vijay" }, "orcid": "0000-0003-3154-9429" }, { "id": "Spurr-R-J-D", "name": { "family": "Spurr", "given": "Robert J. D." } }, { "id": "Boesch-H", "name": { "family": "Boesch", "given": "Hartmut" }, "orcid": "0000-0003-3944-9879" }, { "id": "Jiang-Yibo", "name": { "family": "Jiang", "given": "Yibo" }, "orcid": "0000-0001-6711-7260" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Evaluation of errors from neglecting polarization in the forward modeling of O_2 A band measurements from space, with relevance to CO_2 column retrieval from polarization-sensitive instruments", "ispublished": "pub", "full_text_status": "restricted", "keywords": "Reflected; Top of the atmosphere; Intensity; Polarization; Errors; O2 A band; OCO", "note": "\u00a9 2006 Elsevier Ltd. Received 8 November 2005; accepted 6 February 2006. Available online 20 March 2006. This work was supported in part by NASA Grant NAG1-1806 and the Orbiting Carbon Observatory\n(OCO) Project at JPL. We would like to thank Joop Hovenier and Johan de Haan for providing us with a\ndoubling-adding vector RT code to verify the results from VLIDORT. We would also like to acknowledge\nDavid Crisp, Run-Lie Shia, Jack Margolis and Xin Guo for reviewing the manuscript, and Charles Miller,\nGeoff Toon and Bhaswar Sen for helpful comments.", "abstract": "Sensitivity studies have been performed to evaluate the errors resulting from ignoring polarization in analyzing spectroscopic measurements of the O_2A band from space, using the Orbiting Carbon Observatory (OCO) as a test case. An 11-layer atmosphere, with both gas and aerosol loading, and bounded from below by a lambertian reflecting surface, was used for the study. The numerical computations were performed with a plane-parallel vectorized discrete ordinate radiative transfer code. Beam and viewing geometry, surface reflectance and aerosol loading were varied one at a time to evaluate and understand the individual errors. Different behavior was observed in the line cores and the continuum because of the different paths taken by the photons in the two cases. The errors were largest when the solar zenith angle was high, and the aerosol loading and surface reflectance low. To understand the effect of neglecting polarization on CO_2 column retrievals, a linear error analysis study was performed on simulated measurements from the OCO spectral regions, viz. the 1.61 and 2.06 \u03bcm CO_2 bands and the O_2A band. It was seen that neglecting polarization could introduce errors as high as 10 ppm, which is substantially larger than the required retrieval precision of \u223c2 ppm. A variety of approaches, including orders of scattering, spectral binning and the use of lookup tables are being explored to reduce the errors.", "date": "2007-01", "date_type": "published", "publication": "Journal of Quantitative Spectroscopy and Radiative Transfer", "volume": "103", "number": "2", "publisher": "Elsevier", "pagerange": "245-259", "id_number": "CaltechAUTHORS:20140826-092958397", "issn": "0022-4073", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140826-092958397", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NAG1-1806" }, { "agency": "Orbiting Carbon Observatory (OCO)" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/j.jqsrt.2006.02.073", "resource_type": "article", "pub_year": "2007", "author_list": "Natraj, Vijay; Spurr, Robert J. D.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/bmf4y-fen65", "eprint_id": 48894, "eprint_status": "archive", "datestamp": "2023-08-22 08:02:10", "lastmod": "2023-10-17 20:31:12", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Guo-Xin", "name": { "family": "Guo", "given": "Xin" } }, { "id": "Natraj-V", "name": { "family": "Natraj", "given": "Vijay" }, "orcid": "0000-0003-3154-9429" }, { "id": "Feldman-D-R", "name": { "family": "Feldman", "given": "Daniel R." } }, { "id": "Spurr-R-J-D", "name": { "family": "Spurr", "given": "Robert J. D." } }, { "id": "Shia-Run-Lie", "name": { "family": "Shia", "given": "Run-Lie" }, "orcid": "0000-0003-1911-3120" }, { "id": "Sander-S-P", "name": { "family": "Sander", "given": "Stanley P." }, "orcid": "0000-0003-1424-3620" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Retrieval of ozone profile from ground-based measurements with polarization: A synthetic study", "ispublished": "pub", "full_text_status": "restricted", "keywords": "Retrieval; Troposphere; Ozone; Polarization; Scattering; Aerosol", "note": "\u00a9 2006 Elsevier Ltd. Received 6 May 2006. Revised 27 May 2006. Accepted 30 May 2006. Available online 30 June 2006. We appreciate the helpful comments from J. Margolis, M. Newchurch, K. Chance, X. Liu, F. Mills, J. Herman, L. Li, X. Jiang, Y. Jiang, S. Herman, C. Kolb and two anonymous reviewers. This research is supported in part by NASA Grant NAG1-02081 and JPL Grant P421407 to California Institute of\nTechnology.", "abstract": "We perform a retrieval based on optimal estimation theory to retrieve the vertical distribution of ozone from simulated spectra in the Huggins bands. The model atmosphere includes scattering by aerosol as well as Rayleigh scattering. The virtual instrument is ground-based and zenith-viewing. Using this algorithm, we show that it is possible to retrieve the ozone profile provided that the spectral resolution is at least 0.2 nm and the signal to noise ratio greater than 500. Our synthetic retrievals suggest that if we are able to measure the Stokes parameters Q, U and V with accuracy comparable to that of the intensity, the information contained in the measurements, and therefore the inversion, will improve. Furthermore, we find that the measurement of the full Stokes vector from the ground-based instrument will especially enhance the retrieval of tropospheric ozone. Utilizing concepts from information theory, our arguments are confirmed by increases in the degrees of freedom and the Shannon information content in the simulated measurements.", "date": "2007-01", "date_type": "published", "publication": "Journal of Quantitative Spectroscopy and Radiative Transfer", "volume": "103", "number": "1", "publisher": "Elsevier", "pagerange": "175-192", "id_number": "CaltechAUTHORS:20140826-090755061", "issn": "0022-4073", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140826-090755061", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NAG1-02081" }, { "agency": "JPL", "grant_number": "P421407" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/j.jqsrt.2006.05.008", "resource_type": "article", "pub_year": "2007", "author_list": "Guo, Xin; Natraj, Vijay; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/4gr9c-e3y25", "eprint_id": 48830, "eprint_status": "archive", "datestamp": "2023-08-22 07:57:29", "lastmod": "2024-01-13 16:07:55", "type": "book_section", "metadata_visibility": "show", "creators": { "items": [ { "id": "Mills-F-P", "name": { "family": "Mills", "given": "Franklin P." } }, { "id": "Esposito-L-W", "name": { "family": "Esposito", "given": "Larry W." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Atmospheric Composition, Chemistry, and Clouds", "ispublished": "unpub", "full_text_status": "public", "keywords": "Venus (Planet)\u2014Exploration; Venus (Planet)\u2014Surface", "note": "\u00a9 2007 American Geophysical Union.\n\nHelpful comments were received from two\nanonymous referees and Dr. Thomas Cravens. YLY was supported\nin part by NASA grant NN X07AI63G to the California Institute of\nTechnology. This research was partially supported under the Australian\nResearch Council's Discovery Projects funding scheme.\n\nPublished - Yung_2007p73.pdf
", "abstract": "Venus' atmosphere has a rich chemistry involving interactions among sulfur,\nchlorine, nitrogen, hydrogen, and oxygen radicals. The chemical regimes in the\natmosphere range from ion-neutral reactions in the ionosphere to photochemistry\nin the middle atmosphere to thermal equilibrium chemistry and surface-atmosphere\nreactions in the lower atmosphere. This variety makes Venus an important planet\nto understand within the context of terrestrial-like planets, both in our own solar\nsystem and outside it. The primary chemical cycles are believed known but surprisingly\nfew details about these cycles have been fully verified by concurrence\namong observations, experiments, and modeling. Good models have been developed\nthat account for many properties of the cloud layers, but the size distribution,\nshape, and composition of the majority of the aerosol mass are still open issues.\nThis chapter reviews the state of knowledge prior to the Venus Express mission\nfor the composition, chemistry, and clouds of the neutral atmosphere on Venus.\nObservations by instruments on Venus Express, in combination with ground-based\nobservations, laboratory experiments, and numerical modeling, should answer some\nof the major open questions regarding the composition, chemistry, and clouds of\nVenus' atmosphere.", "date": "2007", "date_type": "published", "publisher": "American Geophysical Union", "place_of_pub": "Washington, DC", "pagerange": "73-100", "id_number": "CaltechAUTHORS:20140825-083854023", "isbn": "9780875904412", "book_title": "Exploring Venus as a Terrestrial Planet", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140825-083854023", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NN X07AI63G" }, { "agency": "Australian Research Council" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "contributors": { "items": [ { "id": "Esposito-L-W", "name": { "family": "Esposito", "given": "Larry" } }, { "id": "Stofan-E-R", "name": { "family": "Stofan", "given": "Ellen Renee" } }, { "id": "Cravens-T-E", "name": { "family": "Cravens", "given": "Thomas E." } } ] }, "doi": "10.1029/176GM06", "primary_object": { "basename": "Yung_2007p73.pdf", "url": "https://authors.library.caltech.edu/records/4gr9c-e3y25/files/Yung_2007p73.pdf" }, "resource_type": "book_section", "pub_year": "2007", "author_list": "Mills, Franklin P.; Esposito, Larry W.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/cqy0a-9dm51", "eprint_id": 7061, "eprint_status": "archive", "datestamp": "2023-08-22 07:50:15", "lastmod": "2023-10-16 20:41:25", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Liang-Mao-Chang", "name": { "family": "Liang", "given": "Mao-Chang" }, "orcid": "0000-0002-5294-9344" }, { "id": "Hartman-Hyman", "name": { "family": "Hartman", "given": "Hyman" } }, { "id": "Kopp-R-E", "name": { "family": "Kopp", "given": "Robert E." }, "orcid": "0000-0003-4016-9428" }, { "id": "Kirschvink-J-L", "name": { "family": "Kirschvink", "given": "Joseph L." }, "orcid": "0000-0001-9486-6689" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Production of hydrogen peroxide in the atmosphere of a Snowball Earth and the origin of oxygenic photosynthesis", "ispublished": "pub", "full_text_status": "public", "keywords": "atmospheric processes; Paleoproterozoic; photochemistry", "note": "\u00a9 2006 by The National Academy of Sciences of the USA. Freely available online through the PNAS open access option. \n\nCommunicated by Norman H. Sleep, Stanford University, Stanford, CA, October 6, 2006 (received for review November 15, 2005). Published online before print November 30, 2006, 10.1073/pnas.0608839103 \n\nWe thank C. Boxe, J. R. Leadbetter, and A. L. Sessions for helpful discussions and R. Pierrehumbert and an anonymous referee for helping improve this work. M.-C.L. and Y.L.Y. were supported by National Aeronautics and Space Administration Grant NNG06GF33G and astrobiology institutional support under Cooperative Agreement CAN-00-OSS-01. H.H. was supported by National Science Foundation Grant 00205512. J.L.K. and R.E.K. were supported by the Agouron Institute.\n\nAuthor contributions: M.-C.L., H.H., J.L.K., and Y.L.Y. designed research; M.-C.L. performed research; and M.-C.L., H.H., R.E.K., J.L.K., and Y.L.Y. wrote the paper. \n\nThe authors declare no conflict of interest.\n\nPublished - LIApnas06b.pdf
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", "abstract": "During Proterozoic time, Earth experienced two intervals with one or more episodes of low-latitude glaciation, which are probable \"Snowball Earth\" events. Although the severity of the historical glaciations is debated, theoretical \"hard Snowball\" conditions are associated with the nearly complete shutdown of the hydrological cycle. We show here that, during such long and severe glacial intervals, a weak hydrological cycle coupled with photochemical reactions involving water vapor would give rise to the sustained production of hydrogen peroxide. The photochemical production of hydrogen peroxide has been proposed previously as the primary mechanism for oxidizing the surface of Mars. During a Snowball, hydrogen peroxide could be stored in the ice; it would then be released directly into the ocean and the atmosphere upon melting and could mediate global oxidation events in the aftermath of the Snowball, such as that recorded in the Fe and Mn oxides of the Kalahari Manganese Field, deposited after the Paleoproterozoic low-latitude Makganyene glaciation. Low levels of peroxides and molecular oxygen generated during Archean and earliest Proterozoic non-Snowball glacial intervals could have driven the evolution of oxygen-mediating and -using enzymes and thereby paved the way for the eventual appearance of oxygenic photosynthesis.", "date": "2006-12-12", "date_type": "published", "publication": "Proceedings of the National Academy of Sciences of the United States of America", "volume": "103", "number": "50", "publisher": "National Academy of Sciences", "pagerange": "18996-18999", "id_number": "CaltechAUTHORS:LIApnas06b", "issn": "0027-8424", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:LIApnas06b", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NNG06GF33G" }, { "agency": "NASA", "grant_number": "CAN-00-OSS-01" }, { "agency": "NSF", "grant_number": "EAR-00205512" }, { "agency": "Agouron Institute" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1073/pnas.0608839103", "pmcid": "PMC1672611", "primary_object": { "basename": "LIApnas06bfig1.gif", "url": "https://authors.library.caltech.edu/records/cqy0a-9dm51/files/LIApnas06bfig1.gif" }, "related_objects": [ { "basename": "LIApnas06bfig2.gif", "url": "https://authors.library.caltech.edu/records/cqy0a-9dm51/files/LIApnas06bfig2.gif" }, { "basename": "LIApnas06bfig3.gif", "url": "https://authors.library.caltech.edu/records/cqy0a-9dm51/files/LIApnas06bfig3.gif" }, { "basename": "LIApnas06bfig4.jpg", "url": "https://authors.library.caltech.edu/records/cqy0a-9dm51/files/LIApnas06bfig4.jpg" }, { "basename": "medium.png", "url": "https://authors.library.caltech.edu/records/cqy0a-9dm51/files/medium.png" }, { "basename": "small.png", "url": "https://authors.library.caltech.edu/records/cqy0a-9dm51/files/small.png" }, { "basename": "LIApnas06b.pdf", "url": "https://authors.library.caltech.edu/records/cqy0a-9dm51/files/LIApnas06b.pdf" } ], "resource_type": "article", "pub_year": "2006", "author_list": "Liang, Mao-Chang; Hartman, Hyman; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/gb880-e9j38", "eprint_id": 46635, "eprint_status": "archive", "datestamp": "2023-08-22 07:48:17", "lastmod": "2023-10-26 19:53:39", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Boesch-H", "name": { "family": "B\u00f6sch", "given": "H." }, "orcid": "0000-0003-3944-9879" }, { "id": "Toon-G-C", "name": { "family": "Toon", "given": "G. C." }, "orcid": "0000-0003-4174-7541" }, { "id": "Sen-B", "name": { "family": "Sen", "given": "B." } }, { "id": "Washenfelder-R-A", "name": { "family": "Washenfelder", "given": "R. A." }, "orcid": "0000-0002-8106-3702" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Buchwitz-M", "name": { "family": "Buchwitz", "given": "M." } }, { "id": "de-Beek-R", "name": { "family": "de Beek", "given": "R." } }, { "id": "Burrows-J-P", "name": { "family": "Burrows", "given": "J. P." } }, { "id": "Crisp-D", "name": { "family": "Crisp", "given": "D." }, "orcid": "0000-0002-4573-9998" }, { "id": "Christi-M", "name": { "family": "Christi", "given": "M." } }, { "id": "Connor-B-J", "name": { "family": "Connor", "given": "B. J." } }, { "id": "Natraj-V", "name": { "family": "Natraj", "given": "V." }, "orcid": "0000-0003-3154-9429" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Y. L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Space-based near-infrared CO_2 measurements: Testing the Orbiting Carbon Observatory retrieval algorithm and validation concept using SCIAMACHY observations over Park Falls, Wisconsin", "ispublished": "pub", "full_text_status": "public", "keywords": "satellite remote sensing; carbon dioxide column; near-infrared measurements", "note": "\u00a9 2006 American Geophysical Union. \n\nReceived 17 January 2006; revised 20 June 2006; accepted 30 June 2006; article first published online 6 December 2006. \n\nThis work was supported by the Orbiting Carbon Observatory (OCO) project through NASA's Earth System Science Pathfinder (ESSP) program. We thank ESA and DLR for making available\nSCIAMACHY Level 1 data. We thank the Netherlands Sciamachy Data Center (NL-SCIA-DC), maintained by KNMI and SRON, for providing us data and processing services. We have used NCEP and ECWMF ERA-40 Reanalysis data provided by the NOAA-CIRES Climate Diagnostics Center, Boulder, Colorado, from their Web site at http://www.cdc.noaa.gov and by the European Centre for Medium-Range Weather Forecasts (ECMWF), respectively. We would like to thank Dan Feldman, Hari Nair,\nCharles Miller, Ross Salawitch, and Rob Spurr for many fruitful discussions. University of Bremen was funded by DLR/BMBF grant 50EE0027 (SADOS). Research at the Jet Propulsion Laboratory, California Institute of\nTechnology, is performed under contract with NASA.\n\nPublished - jgrd12916.pdf
Supplemental Material - jgrd12916-sup-0001-readme.txt
Supplemental Material - jgrd12916-sup-0002-ts01.txt
Supplemental Material - jgrd12916-sup-0003-ts02.txt
Supplemental Material - jgrd12916-sup-0004-t01.txt
", "abstract": "Space-based measurements of reflected sunlight in the near-infrared (NIR) region promise to yield accurate and precise observations of the global distribution of atmospheric CO_2. The Orbiting Carbon Observatory (OCO) is a future NASA mission, which will use this technique to measure the column-averaged dry air mole fraction of CO_2 (X_(CO)_2) with the precision and accuracy needed to quantify CO_2 sources and sinks on regional scales (\u223c1000 \u00d7 1000 km^2) and to characterize their variability on seasonal timescales. Here, we have used the OCO retrieval algorithm to retrieve (X_(CO)_2) and surface pressure from space-based Scanning Imaging Absorption Spectrometer for Atmospheric Chartography (SCIAMACHY) measurements and from coincident ground-based Fourier transform spectrometer (FTS) measurements of the O_2 A band at 0.76 \u03bcm and the 1.58 \u03bcm CO_2 band for Park Falls, Wisconsin. Even after accounting for a systematic error in our representation of the O_2 absorption cross sections, we still obtained a positive bias between SCIAMACHY and FTS (X_(CO)_2) retrievals of \u223c3.5%. Additionally, the retrieved surface pressures from SCIAMACHY systematically underestimate measurements of a calibrated pressure sensor at the FTS site. These findings lead us to speculate about inadequacies in the forward model of our retrieval algorithm. By assuming a 1% intensity offset in the O_2 A band region for the SCIAMACHY (X_(CO)_2) retrieval, we significantly improved the spectral fit and achieved better consistency between SCIAMACHY and FTS (X_(CO)_2) retrievals. We compared the seasonal cycle of (X_(CO)_2)at Park Falls from SCIAMACHY and FTS retrievals with calculations of the Model of Atmospheric Transport and Chemistry/Carnegie-Ames-Stanford Approach (MATCH/CASA) and found a good qualitative agreement but with MATCH/CASA underestimating the measured seasonal amplitude. Furthermore, since SCIAMACHY observations are similar in viewing geometry and spectral range to those of OCO, this study represents an important test of the OCO retrieval algorithm and validation concept using NIR spectra measured from space. Finally, we argue that significant improvements in precision and accuracy could be obtained from a dedicated CO_2 instrument such as OCO, which has much higher spectral and spatial resolutions than SCIAMACHY. These measurements would then provide critical data for improving our understanding of the carbon cycle and carbon sources and sinks.", "date": "2006-12-06", "date_type": "published", "publication": "Journal of Geophysical Research D", "volume": "111", "number": "D23", "publisher": "American Geophysical Union", "pagerange": "Art. No. D23302", "id_number": "CaltechAUTHORS:20140702-104030630", "issn": "0148-0227", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140702-104030630", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA" }, { "agency": "Bundesministerium f\u00fcr Bildung und Forschung (BMBF)", "grant_number": "50EE0027" }, { "agency": "Deutsches Zentrum f\u00fcr Luft- und Raumfahrt (DLR)" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2006JD007080", "primary_object": { "basename": "jgrd12916-sup-0001-readme.txt", "url": "https://authors.library.caltech.edu/records/gb880-e9j38/files/jgrd12916-sup-0001-readme.txt" }, "related_objects": [ { "basename": "jgrd12916-sup-0002-ts01.txt", "url": "https://authors.library.caltech.edu/records/gb880-e9j38/files/jgrd12916-sup-0002-ts01.txt" }, { "basename": "jgrd12916-sup-0003-ts02.txt", "url": "https://authors.library.caltech.edu/records/gb880-e9j38/files/jgrd12916-sup-0003-ts02.txt" }, { "basename": "jgrd12916-sup-0004-t01.txt", "url": "https://authors.library.caltech.edu/records/gb880-e9j38/files/jgrd12916-sup-0004-t01.txt" }, { "basename": "jgrd12916.pdf", "url": "https://authors.library.caltech.edu/records/gb880-e9j38/files/jgrd12916.pdf" } ], "resource_type": "article", "pub_year": "2006", "author_list": "B\u00f6sch, H.; Toon, G. C.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/b9few-jz751", "eprint_id": 48785, "eprint_status": "archive", "datestamp": "2023-09-15 04:49:07", "lastmod": "2023-10-23 21:10:17", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Ruzmaikin-A", "name": { "family": "Ruzmaikin", "given": "Alexander" } }, { "id": "Feynman-J", "name": { "family": "Feynman", "given": "Joan" } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Is solar variability reflected in the Nile River?", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2006 American Geophysical Union.\n\nReceived 1 May 2006; revised 5 July 2006; accepted 9 August 2006; published 11 November 2006.\n\nWe thank the reviewers for critical and helpful comments. We are grateful to Don Percival for providing the Nile\ndata. We also thank the participants of the SORCE 2005 meeting and of Y. Yung's seminar at Caltech for helpful discussions of the results presented in this paper. A.R. thanks N. Huang and P. Flandrin for helpful advice on\nthe application of the EMD. This research was carried out in part at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with NASA. Y.L.Y. was supported by NASA grant NNG04GN02G to the California Institute of Technology.\n\nPublished - jgrd13171.pdf
", "abstract": "We investigate the possibility that solar variability influences North African climate by using annual records of the water level of the Nile collected in 622\u20131470 A.D. The time series of these records are nonstationary, in that the amplitudes and frequencies of the quasi-periodic variations are time-dependent. We apply the Empirical Mode Decomposition technique especially designed to deal with such time series. We identify two characteristic timescales in the records that may be linked to solar variability: a period of about 88 years and one exceeding 200 years. We show that these timescales are present in the number of auroras reported per decade in the Northern Hemisphere at the same time. The 11-year cycle is seen in the Nile's high-water level variations, but it is damped in the low-water anomalies. We suggest a possible physical link between solar variability and the low-frequency variations of the Nile water level. This link involves the influence of solar variability on the atmospheric Northern Annual Mode and on its North Atlantic Ocean and Indian Ocean patterns that affect the rainfall over the sources of the Nile in eastern equatorial Africa.", "date": "2006-11-16", "date_type": "published", "publication": "Journal of Geophysical Research D", "volume": "111", "number": "D21", "publisher": "American Geophysical Union", "pagerange": "Art. No. D21114", "id_number": "CaltechAUTHORS:20140821-154600521", "issn": "0148-0227", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140821-154600521", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NNG04GN02G" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2006JD007462", "primary_object": { "basename": "jgrd13171.pdf", "url": "https://authors.library.caltech.edu/records/b9few-jz751/files/jgrd13171.pdf" }, "resource_type": "article", "pub_year": "2006", "author_list": "Ruzmaikin, Alexander; Feynman, Joan; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/89qny-whj61", "eprint_id": 48802, "eprint_status": "archive", "datestamp": "2023-08-22 06:54:59", "lastmod": "2023-10-17 20:26:38", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Pickett-H-M", "name": { "family": "Pickett", "given": "H. M." } }, { "id": "Read-W-G", "name": { "family": "Read", "given": "W. G." } }, { "id": "Lee-K-K", "name": { "family": "Lee", "given": "K. K." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Y. L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Observation of night OH in the mesosphere", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2006 The American Geophysical Union.\n\nReceived 15 May 2006; Revised 14 August 2006; Accepted 30 August 2006; Published 6 October 2006.\n\nWe wish to thank C. Miller and S. Sander for valuable discussions and all who helped make the Aura OH measurements\npossible. KKL was supported by a Summer Undergraduate Research Fellowship at the California Institute of Technology. YLY was supported by NASA grant NNG04GD76G to the California Institute of Technology. Research at the Jet Propulsion Laboratory, California Institute of Technology,\nis performed under contract with the National Aeronautics and Space Administration.\n\nPublished - grl21867.pdf
Supplemental Material - grl21867-sup-0001-readme.txt
Supplemental Material - grl21867-sup-0002-ts01.txt
Supplemental Material - grl21867-sup-0003-ts01.pdf
", "abstract": "Satellite measurements from the Aura MLS instrument show a layer of OH near 82 km in the night. This layer confirms earlier measurements by ground-based LIDAR. The MLS and LIDAR observations measure OH in the lowest vibrational state and are distinct, but related chemically, from vibrationally-excited emission from the OH Meinel bands in the near infrared. The Caltech 1-D model has been extended to include vibrational dependence of OH reactions and shows good agreement with MLS OH data and with observations of the Meinel bands. The model shows a chemical lifetime of HO_x that increases from less than a day at 80 km to over a month at 87 km. Above this altitude transport processes become an important part of HO_x chemistry. The model predicts that ground state OH represents 99% of the total OH up to 84 km.", "date": "2006-10", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "33", "number": "19", "publisher": "American Geophysical Union", "pagerange": "Art. No. L19808", "id_number": "CaltechAUTHORS:20140822-092816343", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140822-092816343", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Caltech Summer Undergraduate Research Fellowship (SURF)" }, { "agency": "NASA", "grant_number": "NNG04GD76G" }, { "agency": "NASA/JPL/Caltech" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2006GL026910", "primary_object": { "basename": "grl21867.pdf", "url": "https://authors.library.caltech.edu/records/89qny-whj61/files/grl21867.pdf" }, "related_objects": [ { "basename": "grl21867-sup-0001-readme.txt", "url": "https://authors.library.caltech.edu/records/89qny-whj61/files/grl21867-sup-0001-readme.txt" }, { "basename": "grl21867-sup-0002-ts01.txt", "url": "https://authors.library.caltech.edu/records/89qny-whj61/files/grl21867-sup-0002-ts01.txt" }, { "basename": "grl21867-sup-0003-ts01.pdf", "url": "https://authors.library.caltech.edu/records/89qny-whj61/files/grl21867-sup-0003-ts01.pdf" } ], "resource_type": "article", "pub_year": "2006", "author_list": "Pickett, H. M.; Read, W. G.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/cahhn-x8497", "eprint_id": 6098, "eprint_status": "archive", "datestamp": "2023-08-22 06:52:48", "lastmod": "2023-10-16 20:08:08", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Tian-Baijun", "name": { "family": "Tian", "given": "Baijun" } }, { "id": "Waliser-D-E", "name": { "family": "Waliser", "given": "Duane E." } }, { "id": "Fetzer-E-J", "name": { "family": "Fetzer", "given": "Eric J." } }, { "id": "Lambrigtsen-B-H", "name": { "family": "Lambrigtsen", "given": "Bjorn H." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Wang-Bin", "name": { "family": "Wang", "given": "Bin" } } ] }, "title": "Vertical Moist Thermodynamic Structure and Spatial\u2013Temporal Evolution of the MJO in AIRS Observations", "ispublished": "pub", "full_text_status": "public", "keywords": "Thermodynamics, Satellite observations, Moisture", "note": "\u00a9 2006 American Meteorological Society \n\nManuscript received 15 November 2005, in final form 3 March 2006 \n\nThis work was supported by the AIRS project at Jet Propulsion Laboratory (JPL) and JPL's Research and Technology Development program. In addition, the second author was supported by JPL's Human Resources Development fund. The research at JPL, California Institute of Technology was performed under contracts with the National Aeronautics and Space Administration. The AIRS level 3 data as well as the NCEP PREPQC radiosonde data were provided by Stephanie Granger, Ed Olsen, and Sung-Yung Lee, who also provided assistance in the analysis. The TRMM 3B42 rainfall data were downloaded from GSFC DAAC web site. The NCEP and NCEP2 reanalysis data were provided by the NOAA\u2013CIRES Climate Diagnostics Center, Boulder, Colorado, from their Web site. Insightful reviews and constructive comments from George Kiladis and two anonymous reviewers as well as helpful discussions with Mous Chahine, Evan Fishbein, Xiouhua Fu, William Lau, and Ken Sperber are appreciated. The first author also wants to thank Mike Black and Xun Jiang for programming help.", "abstract": "The atmospheric moisture and temperature profiles from the Atmospheric Infrared Sounder (AIRS)/Advanced Microwave Sounding Unit on the NASA Aqua mission, in combination with the precipitation from the Tropical Rainfall Measuring Mission (TRMM), are employed to study the vertical moist thermodynamic structure and spatial\u2013temporal evolution of the Madden\u2013Julian oscillation (MJO). The AIRS data indicate that, in the Indian Ocean and western Pacific, the temperature anomaly exhibits a trimodal vertical structure: a warm (cold) anomaly in the free troposphere (800\u2013250 hPa) and a cold (warm) anomaly near the tropopause (above 250 hPa) and in the lower troposphere (below 800 hPa) associated with enhanced (suppressed) convection. The AIRS moisture anomaly also shows markedly different vertical structures as a function of longitude and the strength of convection anomaly. Most significantly, the AIRS data demonstrate that, over the Indian Ocean and western Pacific, the enhanced (suppressed) convection is generally preceded in both time and space by a low-level warm and moist (cold and dry) anomaly and followed by a low-level cold and dry (warm and moist) anomaly. \n\nThe MJO vertical moist thermodynamic structure from the AIRS data is in general agreement, particularly in the free troposphere, with previous studies based on global reanalysis and limited radiosonde data. However, major differences in the lower-troposphere moisture and temperature structure between the AIRS observations and the NCEP reanalysis are found over the Indian and Pacific Oceans, where there are very few conventional data to constrain the reanalysis. Specifically, the anomalous lower-troposphere temperature structure is much less well defined in NCEP than in AIRS for the western Pacific, and even has the opposite sign anomalies compared to AIRS relative to the wet/dry phase of the MJO in the Indian Ocean. Moreover, there are well-defined eastward-tilting variations of moisture with height in AIRS over the central and eastern Pacific that are less well defined, and in some cases absent, in NCEP. In addition, the correlation between MJO-related midtropospheric water vapor anomalies and TRMM precipitation anomalies is considerably more robust in AIRS than in NCEP, especially over the Indian Ocean. Overall, the AIRS results are quite consistent with those predicted by the frictional Kelvin\u2013Rossby wave/conditional instability of the second kind (CISK) theory for the MJO.", "date": "2006-10", "date_type": "published", "publication": "Journal of the Atmospheric Sciences", "volume": "63", "number": "10", "publisher": "American Meteorological Society", "pagerange": "2462-2485", "id_number": "CaltechAUTHORS:TIAjas06", "issn": "0022-4928", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:TIAjas06", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1175/JAS3782.1", "primary_object": { "basename": "TIAjas06.pdf", "url": "https://authors.library.caltech.edu/records/cahhn-x8497/files/TIAjas06.pdf" }, "resource_type": "article", "pub_year": "2006", "author_list": "Tian, Baijun; Waliser, Duane E.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/8zyjk-xky02", "eprint_id": 22380, "eprint_status": "archive", "datestamp": "2023-08-22 06:22:02", "lastmod": "2023-10-23 15:54:22", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Cheng-Bing-Meng", "name": { "family": "Cheng", "given": "Bing-Meng" } }, { "id": "Lu-Hsiao-Chi", "name": { "family": "Lu", "given": "Hsiao-Chi" } }, { "id": "Chen-Hong-Kai", "name": { "family": "Chen", "given": "Hong-Kai" } }, { "id": "Bahou-Mohammed", "name": { "family": "Bahou", "given": "Mohammed" } }, { "id": "Lee-Yuan-Pern", "name": { "family": "Lee", "given": "Yuan-Pern" } }, { "id": "Mebel-A-M", "name": { "family": "Mebel", "given": "Alexander M." } }, { "id": "Lee-L-C", "name": { "family": "Lee", "given": "L. C." } }, { "id": "Liang-Mao-Chang", "name": { "family": "Liang", "given": "Mao-Chang" }, "orcid": "0000-0002-5294-9344" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Absorption Cross Sections of NH_3, NH_2D, NHD_2, and ND_3 in the Spectral Range 140-220 nm and Implications for Planetary Isotopic Fractionation", "ispublished": "pub", "full_text_status": "public", "keywords": "astrochemistry; methods: laboratory; molecular data", "note": "\u00a9 2006 American Astronomical Society.\n\nReceived 2006 February 9; accepted 2006 May 2.\n\nB.-M. C. and Y.-P. L. thank the National Science Council\nof Taiwan (grants NSC93-2113-M-213-002 and NSC93-2113-\nM-009-019) for support. L. C. L. thanks for the National Synchrotron Radiation Research Center in Taiwan for a visiting professorship. M.-C. L. and Y. L. Y. were supported by NASA grant NASA5-13296 to the California Institute of Technology.\n\nPublished - CHEapj06.pdf
", "abstract": "Cross sections for photoabsorption of NH_3, NH_2D, NHD_2, and ND_3 in the spectral region 140-220 nm were determined at ~298 K using synchrotron radiation. Absorption spectra of NH_2D and NHD_2 were deduced from spectra of mixtures of NH_3 and ND_3, of which the equilibrium concentrations for all four isotopologues obey statistical distributions. Cross sections of NH_2D, NHD_2, and ND_3 are new. Oscillator strengths, an integration of absorption cross sections over the spectral lines, for both A \u2190 X and B \u2190 X systems of NH_3 agree satisfactorily with previous reports; values for NH_2D, NHD_2, and ND_3 agree with quantum chemical predictions. The photolysis of NH_3 provides a major source of reactive hydrogen in the lower stratosphere and upper troposphere of giant planets such as Jupiter. Incorporating the measured photoabsorption cross sections of NH_3 and NH_2D into the Caltech/JPL photochemical diffusive model for the atmosphere of Jupiter, we find that the photolysis efficiency of NH_2D is lower than that of NH_3 by as much as 30%. The D/H ratio in NH_2D/NH_3 for tracing the microphysics in the troposphere of Jupiter is also discussed.", "date": "2006-08-20", "date_type": "published", "publication": "Astrophysical Journal", "volume": "647", "number": "2", "publisher": "American Astronomical Society", "pagerange": "1535-1542", "id_number": "CaltechAUTHORS:20110218-095953129", "issn": "0004-637X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20110218-095953129", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "National Science Council of Taiwan", "grant_number": "NSC93-2113-M-213-002" }, { "agency": "National Science Council of Taiwan", "grant_number": "NSC93-2113- M-009-019" }, { "agency": "National Synchrotron Radiation Research Center in Taiwan" }, { "agency": "NASA", "grant_number": "NASA5-13296" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1086/505615", "primary_object": { "basename": "CHEapj06.pdf", "url": "https://authors.library.caltech.edu/records/8zyjk-xky02/files/CHEapj06.pdf" }, "resource_type": "article", "pub_year": "2006", "author_list": "Cheng, Bing-Meng; Lu, Hsiao-Chi; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/77n1m-nj641", "eprint_id": 48898, "eprint_status": "archive", "datestamp": "2023-08-22 06:14:11", "lastmod": "2023-10-17 20:31:30", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Parkinson-C-D", "name": { "family": "Parkinson", "given": "C. D." }, "orcid": "0000-0002-5722-2224" }, { "id": "McConnell-J-C", "name": { "family": "McConnell", "given": "J. C." } }, { "id": "Jaffel-L-B", "name": { "family": "Jaffel", "given": "L. Ben" } }, { "id": "Lee-Anthony-Y-T", "name": { "family": "Lee", "given": "A. Y.-T" } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Y. L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Griffioen-E", "name": { "family": "Griffioen", "given": "E." } } ] }, "title": "Deuterium chemistry and airglow in the jovian thermosphere", "ispublished": "pub", "full_text_status": "restricted", "keywords": "Jupiter, atmosphere; Photochemistry; Radiative transfer; Abundances, atmospheres", "note": "\u00a9 2005 Elsevier Inc. Received 23 February 2004; revised 20 September 2005. Available online 21 June 2006. C.D. Parkinson thanks G.R. Gladstone of SWRI for the use of his radiative transfer code. L. Ben Jaffel and C.D. Parkinson\nthank CNRS and INSU for continuing support through the PNP\nProgram. C.D. Parkinson acknowledges that some of this work\nwas supported by the National Aeronautics and Space Administration through the NASA Astrobiology Institute under Cooperative Agreement No. CAN-00-OSS-01 and issued through the Office of Space Science. J. McConnell thanks the Natural Sciences and Engineering Research Council of Canada for continuing support. Part of this work was done at York University. Y.L. Yung and A.Y.-T. Lee acknowledge support by NASA Grant NASA5-13296 to the California Institute of Technology.", "abstract": "We present a detailed study of the distribution of key deuterated species (viz., atomic D and HD) and the associated deuterium Lyman-\u03b1 airglow in the jovian thermosphere. The reactions that appear to govern the abundances of these deuterated species are used in conjunction with C_2-chemistry in a 1-D photochemical-diffusion model. While the D abundance is mainly sensitive to H densities and the vibrational temperature profile, the D vertical distribution also depends on other parameters such as eddy mixing and the uncertain values of some of the reaction rate constants. We consider different scenarios by varying several parameters controlling the D distribution in the thermosphere. A radiative transfer model with coupling of the H and D Lyman-\u03b1 lines is employed to obtain line profiles and total intensities at disk center for these scenarios. This allows a comparison of the impact of various parameters on the jovian D Lyman-\u03b1 emission. A consequence of these chemical processes in the jovian thermosphere is the formation of CH_2D, CH_3D, and C_2H_5D, and other deuterated species. We also discuss the source of these deuterated hydrocarbons and their abundance. We find that HD vibrational chemistry impacts D in the thermosphere, CH_3D and C_2H_5D are vibrationally enhanced in the thermosphere, and variations in abundance of CH_3D and C_2H_5D in the thermosphere may reflect dynamical activity (i.e., K_h) in the jovian upper atmosphere. An observing program dedicated to providing such measurements of these testable phenomena would provide further insight into the synergistic coupling between chemistry, energetics and airglow in the jovian upper atmosphere.", "date": "2006-08", "date_type": "published", "publication": "Icarus", "volume": "183", "number": "2", "publisher": "Elsevier", "pagerange": "451-470", "id_number": "CaltechAUTHORS:20140826-095112257", "issn": "0019-1035", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140826-095112257", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA Astrobiology Institute", "grant_number": "CAN-00-OSS-01" }, { "agency": "Natural Sciences and Engineering Research Council of Canada (NSERC)" }, { "agency": "NASA", "grant_number": "NASA5-13296" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/j.icarus.2005.09.022", "resource_type": "article", "pub_year": "2006", "author_list": "Parkinson, C. D.; McConnell, J. C.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/rcqd3-8kz47", "eprint_id": 48797, "eprint_status": "archive", "datestamp": "2023-08-22 05:59:13", "lastmod": "2023-10-17 20:26:26", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Shia-Run-Lie", "name": { "family": "Shia", "given": "Run-Lie" }, "orcid": "0000-0003-1911-3120" }, { "id": "Liang-Mao-Chang", "name": { "family": "Liang", "given": "Mao-Chang" }, "orcid": "0000-0002-5294-9344" }, { "id": "Miller-C-E", "name": { "family": "Miller", "given": "Charles E." }, "orcid": "0000-0002-9380-4838" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "CO_2 in the upper troposphere: Influence of stratosphere-troposphere exchange", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2006 The American Geophysical Union.\n\nReceived 24 February 2006; Revised 19 May 2006; Accepted 5 June 2006; Published 26 July 2006.\n\nWe thank M. Gerstell, A. Ingersoll, N. Krakauer and L. Chen for reading the manuscript and helpful comments. This work was supported by NASA grant NNG04GD76G to California\nInstitute of Technology. The building of the tropospheric model was supported by NSF grant ATM-0225829 to California Institute of Technology. The research at the Jet Propulsion Laboratory, California Institute of Technology, was performed under contract with the National Aeronautics and Space Administration.\n\nPublished - grl21504.pdf
", "abstract": "A two-dimensional transport model constrained to measured surface CO_2 concentrations was used to simulate the spatial and temporal variation of CO_2 in the atmosphere for the period from 1975 to 2004. We find that the amplitude, phase and shape of the CO_2 seasonal cycle vary as a function of both altitude and latitude. Cross tropopause exchanges, especially the downward branch of the Brewer-Dobson circulation, which brings stratospheric air to the upper troposphere at middle and high latitudes, change the CO_2 concentration and seasonal cycle in the extra-tropics. The model results match recent aircraft measurements of CO_2 in the upper troposphere (Matsueda et al., 2002) remarkably well. We conclude that upper tropospheric CO_2 volume mixing ratios will provide a valuable tool for validating vertical transport. The implications of the CO_2 variation caused by the stratosphere-troposphere exchange for remote sensing of CO_2 are discussed.", "date": "2006-07", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "33", "number": "14", "publisher": "American Geophysical Union", "pagerange": "Art. No. L14814", "id_number": "CaltechAUTHORS:20140822-085810245", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140822-085810245", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NNG04GD76G" }, { "agency": "NSF", "grant_number": "ATM-0225829" }, { "agency": "NASA/JPL/Caltech" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2006GL026141", "primary_object": { "basename": "grl21504.pdf", "url": "https://authors.library.caltech.edu/records/rcqd3-8kz47/files/grl21504.pdf" }, "resource_type": "article", "pub_year": "2006", "author_list": "Shia, Run-Lie; Liang, Mao-Chang; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/30nnw-dw640", "eprint_id": 48786, "eprint_status": "archive", "datestamp": "2023-08-22 05:55:35", "lastmod": "2023-10-17 20:25:54", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Tinetti-G", "name": { "family": "Tinetti", "given": "Giovanna" } }, { "id": "Rashby-S-E", "name": { "family": "Rashby", "given": "Sky" } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Detectability of red-edge-shifted vegetation on terrestrial planets orbiting M stars", "ispublished": "pub", "full_text_status": "public", "keywords": "astrobiology; atmospheric effects; radiative transfer; stars: late-type", "note": "\u00a9 2006 American Astronomical Society.\n\nReceived 2006 February 3; accepted 2006 May 12; published 2006 June 13.\n\nWe would like to thank M. Joshi, V. S. Meadows, D. Crisp,\nand R. L. Shia for their valuable inputs, X. Jiang, V. Natraj, M. C. Liang, X. Guo, M. Gerstell, and C. D. Parkinson for useful comments, and the referee for improvements to the Letter. Part of this work was performed at the California Institute of Technology. G. Tinetti is currently sponsored by the European Space Agency. Y. L. Yung was partly supported by the National Aeronautics and Space Administration through the NASA Astrobiology Institute (CAN-00-OSS-01) and a NASA grant (NASA 5-13296).\n\nPublished - 1538-4357_644_2_L129.pdf
", "abstract": "We have explored the detectability of exovegetation on the surface of a terrestrial planet orbiting an M star. The exovegetation is responsible for producing a pigment-derived surface signature that is redshifted with respect to the Earth vegetation's red edge. The redshift was estimated using a model of leaf optical property spectra (Jacquemoud & Baret) combined with a 3 photon photosynthetic scheme calculated by Wolstencroft & Raven for a possible exovegetation growing on an M star planet. To study the detectability of this surface biosignature on an M star terrestrial planet, we have used the three-dimensional model developed by Tinetti et al. for the case of the Earth. This model can generate disk-averaged spectra and broadband integrated fluxes, which will be useful for future terrestrial planet exploration missions, such as the NASA Terrestrial Planet Finder Coronagraph. Input to this model were the atmospheric profiles and cloud distributions predicted by Joshi and coworkers for a synchronous planet orbiting an M dwarf and the distinctive surface reflectance of the exovegetation. While on Earth this pigment-derived surface feature would be almost completely masked by water absorption, even in a cloud-free atmosphere, we found that the strength of the edge feature on our simulated M star terrestrial planet can exceed that on Earth, given the right conditions. Obviously, the detectability of such biosignatures would be highly dependent on the extent of vegetation surface area, cloud cover, and viewing angle.", "date": "2006-06-20", "date_type": "published", "publication": "Astrophysical Journal Letters", "volume": "644", "number": "2", "publisher": "American Astronomical Society", "pagerange": "L129-L132", "id_number": "CaltechAUTHORS:20140821-154655560", "issn": "2041-8205", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140821-154655560", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "European Space Agency (ESA)" }, { "agency": "NASA Astrobiology Institute", "grant_number": "CAN-00-OSS-01" }, { "agency": "NASA", "grant_number": "NASA 5-13296" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1086/505746", "primary_object": { "basename": "1538-4357_644_2_L129.pdf", "url": "https://authors.library.caltech.edu/records/30nnw-dw640/files/1538-4357_644_2_L129.pdf" }, "resource_type": "article", "pub_year": "2006", "author_list": "Tinetti, Giovanna; Rashby, Sky; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/202pe-y5531", "eprint_id": 48784, "eprint_status": "archive", "datestamp": "2023-08-22 05:52:00", "lastmod": "2023-10-17 20:25:52", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Feldman-D-R", "name": { "family": "Feldman", "given": "D. R." } }, { "id": "Liou-K-N", "name": { "family": "Liou", "given": "K. N." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Tobin-D-C", "name": { "family": "Tobin", "given": "D. C." } }, { "id": "Berk-A", "name": { "family": "Berk", "given": "A." } } ] }, "title": "Direct retrieval of stratospheric CO_2 infrared cooling rate profiles from AIRS data", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2006 by the American Geophysical Union.\n\nReceived 28 September 2005; Revised 31 January 2006; Accepted 24 April 2006; Published 1 June 2006.\n\nWe would like to acknowledge the following individuals for their assistance: David Rider, Jack Margolis, and George\nAumann of JPL, Tony Clough from AER, Inc., Gail Anderson of the NOAA and Xun Jiang, Vijay Natraj, Run-Lie Shia and Xin Guo of Caltech. D. R. Feldman's research was supported in part by NASA grant NNG04GD76G, the NASA Earth Systems Science Fellowship, and the AIRS Project at JPL. A. Berk's collaboration was supported by AFRL/BAA FA8718-04-C-0073.\n\nPublished - grl20775.pdf
", "abstract": "We expand upon methods for retrieving thermal infrared cooling rate profiles, originally developed by Liou and Xue (1988) through application to the inversion of the stratospheric cooling rate produced by carbon dioxide (CO_2) and a formal description of the associated error budget. Specifically, we infer lower- and mid-stratospheric cooling rates from the CO_2 \u03bd_2 band on the basis of selected spectral channels and available data from the Atmospheric Infrared Sounder (AIRS). In order to establish the validity of our results, we compare our retrievals to those calculated from a forward radiative transfer program using retrieved temperature data from spectra taken by the Scanning High-Resolution Interferometer Sounder (S-HIS) on two aircraft campaigns: the Mixed-Phase Arctic Cloud Experiment (MPACE) and the Aura Validation Experiment (AVE) both in Fall, 2004. Reasonable and consistent comparisons are illustrated, revealing that spectral radiance data taken by high-resolution infrared sounders can be used to determine the vertical distribution of radiative cooling due to CO_2.", "date": "2006-06-01", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "33", "number": "11", "publisher": "American Geophysical Union", "pagerange": "Art. No. L11803", "id_number": "CaltechAUTHORS:20140821-153537924", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140821-153537924", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NNG04GD76G" }, { "agency": "NASA Earth Systems Science Fellowship" }, { "agency": "AIRS Project (JPL)" }, { "agency": "AFRL/BAA", "grant_number": "FA8718-04-C-0073" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2005GL024680", "primary_object": { "basename": "grl20775.pdf", "url": "https://authors.library.caltech.edu/records/202pe-y5531/files/grl20775.pdf" }, "resource_type": "article", "pub_year": "2006", "author_list": "Feldman, D. R.; Liou, K. N.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/dgscq-q7e44", "eprint_id": 48862, "eprint_status": "archive", "datestamp": "2023-08-22 05:08:53", "lastmod": "2023-10-17 20:29:31", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Parkinson-C-D", "name": { "family": "Parkinson", "given": "C. D." }, "orcid": "0000-0002-5722-2224" }, { "id": "Stewart-A-I-F", "name": { "family": "Stewart", "given": "A. I. F." } }, { "id": "Wong-A-S", "name": { "family": "Wong", "given": "A. S." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Y. L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Ajello-J-M", "name": { "family": "Ajello", "given": "J. M." } } ] }, "title": "Enhanced transport in the polar mesosphere of Jupiter: Evidence from Cassini UVIS helium 584 \u00c5 airglow", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2006 The American Geophysical Union.\n\nReceived 26 July 2005; Accepted 16 September 2005; Published 11 February 2006.\n\nThis work was supported by NASA grant NAG5-6263 and the National Aeronautics and Space Administration through the NASA Astrobiology Institute under cooperative agreement\nCAN-00-OSS-01 issued through the Office of Space Science. A.I.F.S. acknowledges support from the National Aeronautics and Space Administration through JPL contract 961196 and also the great and successful efforts of the UVIS team. A.S.W. thanks Sushil Atreya for discussion and valuable comments. The authors thank editor Julie Moses and reviewers\nJack McConnell and Mike Summers for their thorough and thoughtful review and comments.\n\nPublished - jgre2060.pdf
", "abstract": "The eddy diffusion profile (K) in the auroral regions of Jupiter is not well determined. However, because of the intense auroral energy input, eddy mixing is expected to be much more effective and may be responsible for the enhancement of heavy hydrocarbon production in the polar region. In this paper, we estimate the increased eddy mixing in the Jovian auroral regions by comparing the Cassini Ultraviolet Imaging Spectrograph (UVIS) observations during the 2000 Jupiter flyby with radiative transfer calculations of the He 584 \u00c5 airglow intensity. We derive a range for the eddy diffusion coefficients at the homopause (K_h) in the auroral regions to be at least 8 \u00d7 10^6 cm^2 s^(\u22121) and possibly greater than 4 \u00d7 10^7 cm^2 s^(\u22121). By comparison, equatorial K_h is on the order of 2 \u00d7 10^6 cm^2 s^(\u22121).", "date": "2006-02-11", "date_type": "published", "publication": "Journal of Geophysical Research E", "volume": "111", "number": "E2", "publisher": "American Geophysical Union", "pagerange": "Art. No. E02002", "id_number": "CaltechAUTHORS:20140825-150926345", "issn": "0148-0227", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140825-150926345", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NAG5-6263" }, { "agency": "NASA Astrobiology Institute", "grant_number": "CAN-00-OSS-01" }, { "agency": "NASA", "grant_number": "961196" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2005JE002539", "primary_object": { "basename": "jgre2060.pdf", "url": "https://authors.library.caltech.edu/records/dgscq-q7e44/files/jgre2060.pdf" }, "resource_type": "article", "pub_year": "2006", "author_list": "Parkinson, C. D.; Stewart, A. I. F.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/4j91z-76j43", "eprint_id": 48823, "eprint_status": "archive", "datestamp": "2023-08-22 05:01:12", "lastmod": "2023-10-17 20:27:34", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Liang-Mao-Chang", "name": { "family": "Liang", "given": "Mao-Chang" }, "orcid": "0000-0002-5294-9344" }, { "id": "Irion-F-W", "name": { "family": "Irion", "given": "Fredrick W." } }, { "id": "Weibel-J-D", "name": { "family": "Weibel", "given": "Jason D." } }, { "id": "Miller-C-E", "name": { "family": "Miller", "given": "Charles E." }, "orcid": "0000-0002-9380-4838" }, { "id": "Blake-G-A", "name": { "family": "Blake", "given": "Geoffrey A." }, "orcid": "0000-0003-0787-1610" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Isotopic composition of stratospheric ozone", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2006 The American Geophysical Union.\n\nReceived 8 June 2005; Revised 23 September 2005; Accepted 24 October 2005; Published 18 January 2006.\n\nSpecial thanks to Yi-Qin Gao for helping us on the ozone formation model.We also thank Mimi Gerstell, Jack Margolis,\nRun-Lie Shia, and Geoff Toon for their helpful comments. This work was supported by an NSF grant ATM-9903790.\n\nPublished - jgrd12427.pdf
Supplemental Material - jgrd12427-sup-0001-t01.txt
", "abstract": "We present a kinetic calculation for the isotopic composition of stratospheric ozone. The calculated enrichments of ^(49)O_3 and ^(50)O_3 are in agreement with atmospheric measurements made at midlatitudes. Integrating the kinetic fractionation processes in the formation and photolysis of ozone, we obtain enrichments of \u223c7.5\u201310.5 and \u223c7.5\u201312.5% (referenced to atmospheric O_2) for \u03b4^(49)O_3 and \u03b4^(50)O_3, respectively, at altitudes between 20 and 35 km; the photolysis in the Hartley band of ozone is responsible for the observed altitude variation. The overall magnitude of the ozone enrichments (\u223c10%) is large compared with that commonly known in atmospheric chemistry and geochemistry. The heavy oxygen atom in ozone is therefore useful as a tracer of chemical species and pathways that involve ozone or its derived products. For example, the mass anomalies of oxygen in two greenhouse gases, CO_2 and N_2O, are likely the consequences of the transfer of heavy oxygen atoms from ozone.", "date": "2006-01-27", "date_type": "published", "publication": "Journal of Geophysical Research D", "volume": "111", "number": "D2", "publisher": "American Geophysical Union", "pagerange": "Art. No. D02302", "id_number": "CaltechAUTHORS:20140822-142117797", "issn": "0148-0227", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140822-142117797", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "ATM-9903790" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2005JD006342", "primary_object": { "basename": "jgrd12427-sup-0001-t01.txt", "url": "https://authors.library.caltech.edu/records/4j91z-76j43/files/jgrd12427-sup-0001-t01.txt" }, "related_objects": [ { "basename": "jgrd12427.pdf", "url": "https://authors.library.caltech.edu/records/4j91z-76j43/files/jgrd12427.pdf" } ], "resource_type": "article", "pub_year": "2006", "author_list": "Liang, Mao-Chang; Irion, Fredrick W.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/5m0hm-r3a89", "eprint_id": 48899, "eprint_status": "archive", "datestamp": "2023-08-22 04:49:36", "lastmod": "2023-10-17 20:31:34", "type": "book_section", "metadata_visibility": "show", "creators": { "items": [ { "id": "Mills-F-P", "name": { "family": "Mills", "given": "F. P." } }, { "id": "Sundaram-M", "name": { "family": "Sundaram", "given": "M." } }, { "id": "Slanger-T-G", "name": { "family": "Slanger", "given": "T. G." } }, { "id": "Allen-M-A", "name": { "family": "Allen", "given": "M." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Y. L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Oxygen chemistry in the Venus middle atmosphere", "ispublished": "unpub", "full_text_status": "restricted", "note": "\u00a9 2006 World Scientific Publishing.\n\nPart of this research was carried out at the Jet Propulsion Laboratory, California\nInstitute of Technology, under contract with NASA. Funding from\nNASA's Planetary Atmospheres program, the Australian Research Council,\nthe Asia Oceania Geosciences Society, and the International Society of\nBiometeorology Tromp Travel Fund is gratefully acknowledged.", "abstract": "Decades of research have sought to understand the similarities and differences\nbetween Venus and Earth. Yet, it is still not clear what chemical processes\nmaintain the long-term stability of Venus' primarily CO_2 atmosphere because,\nuntil recently, the observed limit on O_2 was an order of magnitude smaller\nthan predicted by photochemical model calculations. CO_2 dissociates into CO\nand O after absorbing photons at wavelengths <205 nm. These O atoms should\ncombine to form O_2, and observations of intense airglow, produced as oxygen\nmolecules in the O_2 (a^1 \u0394) and O_2 (c^1 \u03a3) states decay radiatively to the ground\nstate, confirm rapid production of O_2 on both day and night sides. Achieving an\nappropriate balance in numerical models between this rapid production of O_2\nand the rapid destruction implied by the observational upper limits on O_2 has\nbeen a challenge for the past 25 years. Numerical modeling shows that recent\nproposals may resolve this gap between theory and observations, depending\non the rates of poorly constrained reactions. The laboratory and observational\nstudies needed to help resolve remaining questions regarding oxygen chemistry\nin the Venus middle atmosphere are outlined.", "date": "2006", "date_type": "published", "publisher": "World Scientific Publishing", "place_of_pub": "Hackensack, NJ", "pagerange": "109-117", "id_number": "CaltechAUTHORS:20140826-095113678", "isbn": "9789812707192", "book_title": "Advances in geosciences", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140826-095113678", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA" }, { "agency": "Australian Research Council" }, { "agency": "Asia Oceania Geosciences Society" }, { "agency": "International Society of Biometeorology Tromp Travel Fund" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "contributors": { "items": [ { "id": "Ip-Wing-Huen", "name": { "family": "Ip", "given": "Wing-Huen" } } ] }, "resource_type": "book_section", "pub_year": "2006", "author_list": "Mills, F. P.; Sundaram, M.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/bjmmh-8sk66", "eprint_id": 48891, "eprint_status": "archive", "datestamp": "2023-08-22 04:42:24", "lastmod": "2023-10-17 20:31:03", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Liang-Mao-Chang", "name": { "family": "Liang", "given": "Mao-Chang" }, "orcid": "0000-0002-5294-9344" }, { "id": "Shia-Run-Lie", "name": { "family": "Shia", "given": "Run-Lie" }, "orcid": "0000-0003-1911-3120" }, { "id": "Lee-Anthony-Y-T", "name": { "family": "Lee", "given": "Anthony Y. T." } }, { "id": "Allen-M-A", "name": { "family": "Allen", "given": "Mark" } }, { "id": "Friedson-A-J", "name": { "family": "Friedson", "given": "A. James" } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Meridional transport in the stratosphere of Jupiter", "ispublished": "pub", "full_text_status": "public", "keywords": "atmospheric effects; methods: numerical; planetary systems; planets and satellites: individual (Jupiter); radiative transfer", "note": "\u00a9 2005 The American Astronomical Society.\n\nReceived 2005 July 27; accepted 2005 November 15; published 2005 December 5.\n\nThis research was supported in part by NASA grant NAG5-\n6263 to the California Institute of Technology. Special thank\nto Julie Moses for her insightful comments.\n\nPublished - 1538-4357_635_2_L177.pdf
Submitted - 0512068v1.pdf
", "abstract": "The Cassini measurements of C_2H_2 and C_2H_6 at ~5 mbar provide a constraint on meridional transport in the stratosphere of Jupiter. We performed a two-dimensional photochemical calculation coupled with mass transport due to vertical and meridional mixing. The modeled profile of C_2H_2 at latitudes less than 70\u00b0 follows the latitude dependence of the solar insolation, while that of C_2H_6 shows little latitude dependence, consistent with the measurements. In general, our model study suggests that the meridional transport timescale above 5-10 mbar altitude level is \u22731000 yr, and the time could be as short as 10 yr below 10 mbar level, in order to fit the Cassini measurements. The derived meridional transport timescale above the 5 mbar level is 100 times longer than that obtained from the spreading of gas-phase molecules deposited after the impact of Shoemaker-Levy 9 comet. There is no explanation at this time for this discrepancy.", "date": "2005-12-20", "date_type": "published", "publication": "Astrophysical Journal Letters", "volume": "635", "number": "2", "publisher": "American Astronomical Society", "pagerange": "L177-L180", "id_number": "CaltechAUTHORS:20140826-084942295", "issn": "2041-8205", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140826-084942295", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NAG5-6263" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1086/499624", "primary_object": { "basename": "0512068v1.pdf", "url": "https://authors.library.caltech.edu/records/bjmmh-8sk66/files/0512068v1.pdf" }, "related_objects": [ { "basename": "1538-4357_635_2_L177.pdf", "url": "https://authors.library.caltech.edu/records/bjmmh-8sk66/files/1538-4357_635_2_L177.pdf" } ], "resource_type": "article", "pub_year": "2005", "author_list": "Liang, Mao-Chang; Shia, Run-Lie; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/b794x-4q012", "eprint_id": 48825, "eprint_status": "archive", "datestamp": "2023-08-22 04:41:37", "lastmod": "2023-10-17 20:27:39", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Limpasuvan-V", "name": { "family": "Limpasuvan", "given": "Varavut" } }, { "id": "Hartmann-D-L", "name": { "family": "Hartmann", "given": "Dennis L." }, "orcid": "0000-0002-4495-7774" }, { "id": "Thompson-D-W-J", "name": { "family": "Thompson", "given": "David W. J." } }, { "id": "Jeev-K", "name": { "family": "Jeev", "given": "Kumar" } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Stratosphere-troposphere evolution during polar vortex intensification", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2005 The American Geophysical Union.\n\nReceived 31 May 2005; Revised 14 September 2005; Accepted 29 September 2005; Published 17 December 2005.\n\nThe NCEP/NCAR Reanalysis data and Interpolate OLR data are provided by the NOAA-CIRES Climate Diagnostics Center, Boulder, Colorado, from their Web site at http://www.cdc.noaa.gov. The NINO3.4 index is provided by NOAA Climate Prediction Center, Camp Springs, Maryland, from their website at http://www.cpc.ncep.noaa.gov/data/indices/index.html. The authors thank the anonymous reviewers whose comments significantly improved the manuscript. V.L. is supported\nby the National Science Foundation (NSF) under grant ATM-0213248. D.L.H. is supported by the NSF under grant ATM-9873691 from the Climate Dynamics Program. D.W.J.T. is supported by NSF under grants CAREER: ATM-0132190 and ATM-0320959. Y.L.Y. was supported by NASA grants NAG1-1806 and NNG04N02G.\n\nPublished - jgrd12400.pdf
Supplemental Material - jgrd12400-sup-0001-t01.txt
", "abstract": "Stratosphere-troposphere evolution associated with polar vortex intensification (VI) events is examined during the Northern Hemisphere winter. The incipient stage of a VI event is marked by anomalously low wave activity and descending westerly anomalies over the depth of the polar stratosphere. Reduced poleward planetary wave heat flux occurs as the circumpolar wind becomes strongest and pressure anomalies penetrate toward the surface. Descending pressure patterns project strongly onto the positive state of the Northern Hemisphere Annular Mode (NAM). Concurrently, anomalous poleward momentum flux develops in the upper troposphere, and the related tropospheric mean meridional circulation maintains the attendant wind and temperature anomalies against surface drag. The gross behavior of the composite VI event is similar in shape but opposite in sign to that associated with sudden stratospheric warming events (SSWs). However, the descent of the wind and temperature anomalies over the VI life cycle is generally weaker and slower than its SSW counterpart preceding the maximum vortex anomaly. Similarly, after the maximum wind event, the weakening of the winds is faster than the strengthening of the winds after a SSW. This is because stratospheric wind reduction anomalies are produced by wave driving, which can be rapid, and increases in wind speed are associated with the radiative cooling of the polar cap, which happens more gradually. While the contributions of the anomalous momentum fluxes by the quasi-stationary and synoptic eddies are similar to SSWs, the much stronger anomalous momentum flux observed during VI can be attributed to the larger role of eddies with timescales between 15 and 40 days and of wave number 2 scale. Notable differences between VI and SSW appear in the tropical region. In particular, anomalous vortex intensification seems to occur preferentially during La Ni\u00f1a conditions.", "date": "2005-12-17", "date_type": "published", "publication": "Journal of Geophysical Research D", "volume": "110", "number": "D24", "publisher": "American Geophysical Union", "pagerange": "Art. No. D24101", "id_number": "CaltechAUTHORS:20140822-152830734", "issn": "0148-0227", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140822-152830734", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "ATM-0213248" }, { "agency": "NSF", "grant_number": "ATM-9873691" }, { "agency": "NSF", "grant_number": "ATM-0132190" }, { "agency": "NSF", "grant_number": "ATM-0320959" }, { "agency": "NASA", "grant_number": "NAG1-1806" }, { "agency": "NASA", "grant_number": "NNG04N02G" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2005JD006302", "primary_object": { "basename": "jgrd12400-sup-0001-t01.txt", "url": "https://authors.library.caltech.edu/records/b794x-4q012/files/jgrd12400-sup-0001-t01.txt" }, "related_objects": [ { "basename": "jgrd12400.pdf", "url": "https://authors.library.caltech.edu/records/b794x-4q012/files/jgrd12400.pdf" } ], "resource_type": "article", "pub_year": "2005", "author_list": "Limpasuvan, Varavut; Hartmann, Dennis L.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/cmg90-vpc74", "eprint_id": 48822, "eprint_status": "archive", "datestamp": "2023-08-22 04:32:10", "lastmod": "2023-10-17 20:27:32", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Jiang-Xun", "name": { "family": "Jiang", "given": "Xun" }, "orcid": "0000-0001-8932-3807" }, { "id": "Jones-D-B-A", "name": { "family": "Jones", "given": "Dylan B. A." } }, { "id": "Shia-Run-Lie", "name": { "family": "Shia", "given": "Runlie" }, "orcid": "0000-0003-1911-3120" }, { "id": "Waliser-D-E", "name": { "family": "Waliser", "given": "Duane E." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Spatial patterns and mechanisms of the quasi-biennial oscillation\u2013annual beat of ozone", "ispublished": "pub", "full_text_status": "public", "keywords": "QBO-annual beat; Brewer-Dobson circulation; stratospheric ozone", "note": "\u00a9 2005 American Geophysical Union.\n\nReceived 7 April 2005; revised 19 July 2005; accepted 31 August 2005; published 13 December 2005.\n\nWe thank A. Ruzmaikin, J. Feynman,\nV. Natraj, and M. Gerstell for their helpful comments. This work was\nsupported in part by NASA grants NAG1-1806 and NNG04GN02G to the\nCalifornia Institute of Technology. The fourth author was supported by the\nHuman Resources Development Fund at the Jet Propulsion Laboratory.\n\nPublished - jgrd12235.pdf
Supplemental Material - jgrd12235-sup-0001-t01.txt
Supplemental Material - jgrd12235-sup-0002-t02.txt
Supplemental Material - jgrd12235-sup-0003-t03.txt
Supplemental Material - jgrd12235-sup-0004-t04.txt
", "abstract": "An idealized two-dimensional chemistry and transport model is used to investigate the spatial patterns of, and mechanism for, the quasi-biennial oscillation\u2013annual beat (QBO-AB) signal in ozone in the tropics and subtropics. Principal component analysis is applied to the detrended, deseasonalized, and filtered total column ozone anomaly from the standard model. The first two empirical orthogonal functions (EOFs) capture over 98.5% of the total variance. The first EOF, accounting for 70.3% of the variance, displays a structure attributable to the approximately symmetric QBO with a period of 28 months. The second EOF, capturing 28.2% of the variance, is related to the QBO-AB around 20 months. An extended EOF analysis reveals the characteristic pattern of the downward propagation of QBO and upward propagation of QBO-AB. The model results are compared to those from the merged ozone data. Sensitivity experiments indicate that the QBO-AB is produced primarily as a result of the dynamical QBO-AB in the mean meridional circulation and by the interaction between the QBO and the annual cycle in transport, each contributing roughly equally to the forcing of QBO-AB. The interaction between the QBO in the transport fields and the annual cycle in chemistry plays a minor role.", "date": "2005-12", "date_type": "published", "publication": "Journal of Geophysical Research D", "volume": "110", "number": "D23", "publisher": "American Geophysical Union", "pagerange": "Art. No. D23308", "id_number": "CaltechAUTHORS:20140822-133133293", "issn": "0148-0227", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140822-133133293", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NAG1-1806" }, { "agency": "NASA", "grant_number": "NNG04GN02G" }, { "agency": "JPL Human Resources Development Fund" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2005JD006055", "primary_object": { "basename": "jgrd12235-sup-0001-t01.txt", "url": "https://authors.library.caltech.edu/records/cmg90-vpc74/files/jgrd12235-sup-0001-t01.txt" }, "related_objects": [ { "basename": "jgrd12235-sup-0002-t02.txt", "url": "https://authors.library.caltech.edu/records/cmg90-vpc74/files/jgrd12235-sup-0002-t02.txt" }, { "basename": "jgrd12235-sup-0003-t03.txt", "url": "https://authors.library.caltech.edu/records/cmg90-vpc74/files/jgrd12235-sup-0003-t03.txt" }, { "basename": "jgrd12235-sup-0004-t04.txt", "url": "https://authors.library.caltech.edu/records/cmg90-vpc74/files/jgrd12235-sup-0004-t04.txt" }, { "basename": "jgrd12235.pdf", "url": "https://authors.library.caltech.edu/records/cmg90-vpc74/files/jgrd12235.pdf" } ], "resource_type": "article", "pub_year": "2005", "author_list": "Jiang, Xun; Jones, Dylan B. A.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/60n9j-4hv35", "eprint_id": 48867, "eprint_status": "archive", "datestamp": "2023-08-22 04:25:26", "lastmod": "2023-10-17 20:29:44", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Natraj-V", "name": { "family": "Natraj", "given": "Vijay" }, "orcid": "0000-0003-3154-9429" }, { "id": "Jiang-Xun", "name": { "family": "Jiang", "given": "Xun" }, "orcid": "0000-0001-8932-3807" }, { "id": "Shia-Run-Lie", "name": { "family": "Shia", "given": "Run-Lie" }, "orcid": "0000-0003-1911-3120" }, { "id": "Huang-Xianglei", "name": { "family": "Huang", "given": "Xianglei" }, "orcid": "0000-0002-7129-614X" }, { "id": "Margolis-J-S", "name": { "family": "Margolis", "given": "Jack S." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Application of principal component analysis to high spectral resolution radiative transfer: A case study of the O_2 A band", "ispublished": "pub", "full_text_status": "restricted", "keywords": "Radiative transfer; Principal component analysis; Empirical orthogonal function; Remote sensing; Retrieval; O 2 A band", "note": "\u00a9 2005 Elsevier Ltd. Received 28 September 2004, Accepted 12 December 2004, Available online 19 February 2005. This work was supported in part by NASA Grant NAG1-1806 and the Orbiting Carbon Observatory (OCO) Project at JPL.", "abstract": "Radiative transfer computation is the rate-limiting step in most high spectral resolution remote sensing retrieval applications. While several techniques have been proposed to speed up radiative transfer calculations, they all suffer from accuracy considerations. We propose a new method, based on a principal component analysis of the optical properties of the system, that addresses these concerns. Taking atmospheric transmission in the O_2A band as a test case, we reproduced the reflectance spectrum at the top of the atmosphere (TOA), obtained using the multiple scattering code DISORT, with an accuracy of 0.3%, while achieving an order of magnitude improvement in speed.", "date": "2005-11-01", "date_type": "published", "publication": "Journal of Quantitative Spectroscopy and Radiative Transfer", "volume": "95", "number": "4", "publisher": "Elsevier", "pagerange": "539-556", "id_number": "CaltechAUTHORS:20140825-154116143", "issn": "0022-4073", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140825-154116143", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NAG1-1806" }, { "agency": "Orbiting Carbon Observatory (OCO)" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/j.jqsrt.2004.12.024", "resource_type": "article", "pub_year": "2005", "author_list": "Natraj, Vijay; Jiang, Xun; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/96nzp-04q07", "eprint_id": 48889, "eprint_status": "archive", "datestamp": "2023-08-22 04:00:12", "lastmod": "2024-01-13 16:08:03", "type": "book_section", "metadata_visibility": "show", "creators": { "items": [ { "id": "Seager-S", "name": { "family": "Seager", "given": "S." }, "orcid": "0000-0002-6892-6948" }, { "id": "Liang-Mao-Chang", "name": { "family": "Liang", "given": "M.-C." }, "orcid": "0000-0002-5294-9344" }, { "id": "Parkinson-C-D", "name": { "family": "Parkinson", "given": "C. D." }, "orcid": "0000-0002-5722-2224" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Y. L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Exoplanet Atmospheres and Photochemistry", "ispublished": "unpub", "full_text_status": "public", "keywords": "planetary systems; radiative transfer", "note": "\u00a9 2006 International Astronomical Union. Published online: 21 March 2006. S.S. thank the conference organizers for an interesting meeting.\n\nPublished - Yung_2005p491.pdf
", "abstract": "Over 150 extrasolar planets are known to orbit sun-like stars. A growing number of them (9 to date) are transiting \"hot Jupiters\" whose physical characteristics can be measured. Atmospheres of two of these planets have already been detected. We summarize the atmosphere detections and useful upper limits, focusing on the MOST albedo upper limit and II exosphere detection for IID 209458b as the most relevant for photochemical models. We describe our photochemical model for hot Jupiters and present a summary explanation of the main results: a low gas-phase abundance of hydrocarbons; an absence of hydrocarbon hazes; and a large reservoir of II atoms in the upper atmospheres of hot Jupiters. We conclude by relating these model results to the relevant observational data.", "date": "2005-08", "date_type": "published", "publisher": "Cambridge University Press", "id_number": "CaltechAUTHORS:20140826-084801376", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140826-084801376", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "contributors": { "items": [ { "id": "Lis-D-C", "name": { "family": "Lis", "given": "D. C." } }, { "id": "Blake-G-A", "name": { "family": "Blake", "given": "G. A." } }, { "id": "Herbst-E", "name": { "family": "Herbst", "given": "E." } } ] }, "doi": "10.1017/S1743921306007514", "primary_object": { "basename": "Yung_2005p491.pdf", "url": "https://authors.library.caltech.edu/records/96nzp-04q07/files/Yung_2005p491.pdf" }, "resource_type": "book_section", "pub_year": "2005", "author_list": "Seager, S.; Liang, M.-C.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/4j518-70r14", "eprint_id": 48777, "eprint_status": "archive", "datestamp": "2023-08-22 03:58:00", "lastmod": "2023-10-17 20:25:27", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Miller-C-E", "name": { "family": "Miller", "given": "Charles E." }, "orcid": "0000-0002-9380-4838" }, { "id": "Onorato-R-M", "name": { "family": "Onorato", "given": "Robert M." } }, { "id": "Liang-Mao-Chang", "name": { "family": "Liang", "given": "Mao-Chang" }, "orcid": "0000-0002-5294-9344" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Extraordinary isotopic fractionation in ozone photolysis", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2005 The American Geophysical Union.\n\nReceived 6 April 2005; Revised 15 May 2005; Accepted 16 June 2005; Published 23 July 2005.\n\nThe authors thank Drs. J. Brion and S. M. Anderson for sharing their ozone absorption spectra. The research at the\nJet Propulsion Laboratory (JPL), California Institute of Technology was performed under contract with the National Aeronautics and Space Administration.\n\nPublished - grl19978.pdf
", "abstract": "Analysis of experimental ozone absorption spectra reveals that ultraviolet photolysis within the structured Huggins band yields extraordinary wavelength-dependent isotopic fractionation, oscillating between complete enrichment and complete depletion for changes of less than 2 nm in the excitation wavelength. Visible photolysis yields wavelength-dependent fractionation that varies from \u2212300\u2030 to +300\u2030. Photochemical modeling demonstrates photolysis contributes fractionation up to +45\u2030 to the heavy ozone anomaly in the middle stratosphere with measurable ^(17)O and ^(18)O isotopologue-dependent variations as a function of altitude despite the fact that the extraordinary photolysis-induced isotopic fractionation effect is dampened in the atmosphere due to the integration over all excitation wavelengths.", "date": "2005-07-28", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "32", "number": "14", "publisher": "American Geophysical Union", "pagerange": "Art. No. L14814", "id_number": "CaltechAUTHORS:20140821-125830617", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140821-125830617", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2005GL023160", "primary_object": { "basename": "grl19978.pdf", "url": "https://authors.library.caltech.edu/records/4j518-70r14/files/grl19978.pdf" }, "resource_type": "article", "pub_year": "2005", "author_list": "Miller, Charles E.; Onorato, Robert M.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/5me98-0f010", "eprint_id": 48776, "eprint_status": "archive", "datestamp": "2023-08-22 03:50:41", "lastmod": "2023-10-17 20:25:24", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Li-King-Fai", "name": { "family": "Li", "given": "King-Fai" }, "orcid": "0000-0003-0150-2910" }, { "id": "Cagaeo-R-P", "name": { "family": "Cageao", "given": "Richard P." } }, { "id": "Karpilovsky-E-M", "name": { "family": "Karpilovsky", "given": "Elliott M." } }, { "id": "Mills-F-P", "name": { "family": "Mills", "given": "Franklin P." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Margolis-J-S", "name": { "family": "Margolis", "given": "Jack S." } }, { "id": "Sander-S-P", "name": { "family": "Sander", "given": "Stanley P." }, "orcid": "0000-0003-1424-3620" } ] }, "title": "OH column abundance over Table Mountain Facility, California: AM-PM diurnal asymmetry", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2005 The American Geophysical Union.\n\nReceived 23 January 2005; Revised 13 May 2005; Accepted 23 May 2005; Published 8 July 2005.\n\nThis research was carried out by the Jet Propulsion Laboratory, California Institute of Technology, under contract with the National Aeronautics and Space Administration. KFL and EMK acknowledge support from the Caltech Summer Undergraduate Research Fellowship program. This work was supported by the NASA Upper Atmosphere Research Program (JPL), by NASA Grant NAG1-02081\n(California Institute of Technology), and by the Australian Research Council (ANU).\n\nPublished - grl19627.pdf
Supplemental Material - grl19627-sup-0001-t01.txt
Supplemental Material - grl19627-sup-0002-t02.txt
", "abstract": "Observations of the OH column abundance have been made by the Fourier Transform Ultraviolet Spectrometer at the JPL Table Mountain Facility (TMF) near Los Angeles since July 1997. In the January 1998\u2013December 2003 data set we used five OH lines to derive the OH column abundance in the atmosphere. This data set was used to quantify the OH morning/afternoon asymmetry (AMPMDA). An analysis of summer and winter data showed that the daily OH maximum occurred 26\u201336 minutes after solar transit. This phase lag appears to be the primary reason why OH in the afternoon is larger than at corresponding solar zenith angles in the morning throughout the year. A simple heuristic model suggests that the asymmetry is a direct consequence of the finite lifetime of OH. Comparison of the TMF data with earlier results from Fritz Peak Observatory, Colorado, by Burnett et al. reveals significant differences in the behavior of the AMPMDA between the two sites.", "date": "2005-07", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "32", "number": "13", "publisher": "American Geophysical Union", "pagerange": "Art. No. L13813", "id_number": "CaltechAUTHORS:20140821-120128252", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140821-120128252", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Caltech Summer Undergraduate Research Fellowship (SURF)" }, { "agency": "NASA", "grant_number": "NAG1-02081" }, { "agency": "Australian Research Council" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2005GL022521", "primary_object": { "basename": "grl19627-sup-0002-t02.txt", "url": "https://authors.library.caltech.edu/records/5me98-0f010/files/grl19627-sup-0002-t02.txt" }, "related_objects": [ { "basename": "grl19627.pdf", "url": "https://authors.library.caltech.edu/records/5me98-0f010/files/grl19627.pdf" }, { "basename": "grl19627-sup-0001-t01.txt", "url": "https://authors.library.caltech.edu/records/5me98-0f010/files/grl19627-sup-0001-t01.txt" } ], "resource_type": "article", "pub_year": "2005", "author_list": "Li, King-Fai; Cageao, Richard P.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/hqyxq-vca31", "eprint_id": 48860, "eprint_status": "archive", "datestamp": "2023-08-22 03:47:25", "lastmod": "2023-10-17 20:29:27", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Huang-X", "name": { "family": "Huang", "given": "Xianglei" } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk Ling" }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Spatial and spectral variability of the outgoing thermal IR spectra from AIRS: A case study of July 2003", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2005 The American Geophysical Union.\n\nReceived 19 October 2004; Revised 11 March 2005; Accepted 31 March 2005; Published 17 June 2005.\n\nThe AIRS data were obtained from GES Distributed Active Archive Center (http://daac.gsfc.nasa.gov/data/datapool/\nAIRS_DP/). The computer resources for CAM2 simulation were kindly provided by NCAR Scientific Computing Division. We wish to thank R. Goody, V. Ramaswamy, D. Noone, D. Schwarzkopf, J. W. Hurrell, M. Chahine, B. H. Lambrigtsen, and G. Aumann for valuable insights and help. We also thank three anonymous reviewers for improving the quality\nof this paper. This research was done when X. L. Huang was a graduate student at the California Institute of Technology and was supported in part by the AIRS project at JPL and NASA grant NAG1-1806 to the California Institute of Technology.\n\nPublished - jgrd11914.pdf
Supplemental Material - jgrd11914-sup-0001-t01.txt
Supplemental Material - jgrd11914-sup-0002-t02.txt
Supplemental Material - jgrd11914-sup-0003-t03.txt
", "abstract": "Here we present a survey of the spatial variability in different climate zones seen from AIRS data using the spectral EOF analysis. Over the tropical and subtropical oceans, the first principal component (PC1) is mostly due to the thermal contrast between surface and thick cold cloud tops. The second principal component (PC2) is mainly due to the spatial variation of the lower tropospheric humidity (LTH) and the low clouds. The signature of dust aerosol over the Arabian Sea and the Atlantic off the coast of North Africa in the summertime can be clearly seen in the PC2. Both the PC1 and the PC2 capture the upper tropospheric water vapor variability due to the forced orthogonality of EOFs. The third principal component (PC3) is mainly due to the spatial variation of the lower stratospheric temperature. Over the midlatitude oceans, the PC1 is still due to the thermal contrast of emission temperature. During wintertime, the PC2 is mainly due to stratospheric temperature variations. In the summer, the PC2 over the southern hemisphere is still due to stratospheric temperature variations, but in the northern hemisphere it is mainly due to the variations of the LTH and the low clouds. An exploratory study using synthetic spectra based on a NCAR CAM2 simulation shows that the model could account for the essential features in the data as well as provide an explanation of the three leading PCs. Major disagreements exist in the location of the ITCZ, the dust aerosol, and the lower stratospheric temperature.", "date": "2005-06-17", "date_type": "published", "publication": "Journal of Geophysical Research D", "volume": "110", "number": "D12", "publisher": "American Geophysical Union", "pagerange": "Art. No. D12102", "id_number": "CaltechAUTHORS:20140825-141638564", "issn": "0148-0227", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140825-141638564", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "AIRS Project (JPL)" }, { "agency": "NASA", "grant_number": "NAG1-1806" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2004JD005530", "primary_object": { "basename": "jgrd11914-sup-0003-t03.txt", "url": "https://authors.library.caltech.edu/records/hqyxq-vca31/files/jgrd11914-sup-0003-t03.txt" }, "related_objects": [ { "basename": "jgrd11914.pdf", "url": "https://authors.library.caltech.edu/records/hqyxq-vca31/files/jgrd11914.pdf" }, { "basename": "jgrd11914-sup-0001-t01.txt", "url": "https://authors.library.caltech.edu/records/hqyxq-vca31/files/jgrd11914-sup-0001-t01.txt" }, { "basename": "jgrd11914-sup-0002-t02.txt", "url": "https://authors.library.caltech.edu/records/hqyxq-vca31/files/jgrd11914-sup-0002-t02.txt" } ], "resource_type": "article", "pub_year": "2005", "author_list": "Huang, Xianglei and Yung, Yuk Ling" }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/qw93c-86h11", "eprint_id": 34156, "eprint_status": "archive", "datestamp": "2023-08-22 03:46:10", "lastmod": "2023-10-19 14:37:15", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Liang-Mao-Chang", "name": { "family": "Liang", "given": "Mao-Chang" }, "orcid": "0000-0002-5294-9344" }, { "id": "Blake-G-A", "name": { "family": "Blake", "given": "Geoffrey A." }, "orcid": "0000-0003-0787-1610" }, { "id": "Muller-R-P", "name": { "family": "Muller", "given": "Richard P." } }, { "id": "Miller-C-E", "name": { "family": "Miller", "given": "Charles E." }, "orcid": "0000-0002-9380-4838" } ] }, "title": "Reply to comment by R\u00f6ckmann and Kaiser on \"Evidence for O-atom exchange in the O(^1D) + N_2O reaction as the source of mass-independent isotopic fractionation in atmospheric N_2O\"", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2005 by the American Geophysical Union.\n\nReceived 9 February 2005; revised 5 April 2005; accepted 10 May 2005; published 10 June 2005.\nIn summary, we thank R\u00f6ckmann and Kaiser [2005]\nfor their insightful and provocative comments.\n\nPublished - 2005GL022669.pdf
", "abstract": "Based upon the authors' questioning of the existence\nof the C_(2v) intermediate, we have reviewed our evidence for\nthe existence of this state. It now appears that this state was in fact an artifact of our calculation [Yung et al., 2004], and was a saddle point rather than a true minimum. Our desire to provide a timely response to this criticism has kept us from determining exactly what minimum structure will be obtained by a full minimization at the level of theory employed. However, it is clear that the C_(2v) symmetry of the compound is broken in such a way that the two N-O bonds are no longer equivalent. We are grateful to the authors for helping us resolve this issue.", "date": "2005-06-10", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "32", "number": "11", "publisher": "American Geophysical Union", "pagerange": "Art. No. L11808", "id_number": "CaltechAUTHORS:20120917-160257223", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20120917-160257223", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2005GL022669", "primary_object": { "basename": "2005GL022669.pdf", "url": "https://authors.library.caltech.edu/records/qw93c-86h11/files/2005GL022669.pdf" }, "resource_type": "article", "pub_year": "2005", "author_list": "Yung, Yuk L.; Liang, Mao-Chang; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/nx4m0-82364", "eprint_id": 48897, "eprint_status": "archive", "datestamp": "2023-08-22 03:35:03", "lastmod": "2023-10-17 20:31:25", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Nair-H", "name": { "family": "Nair", "given": "Hair" } }, { "id": "Summers-M-E", "name": { "family": "Summers", "given": "Michael E." } }, { "id": "Miller-C-E", "name": { "family": "Miller", "given": "Charles E." }, "orcid": "0000-0002-9380-4838" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Isotopic fractionation of methane in the martian atmosphere", "ispublished": "pub", "full_text_status": "restricted", "keywords": "Exobiology; Marsatmosphere; Photochemistry", "note": "\u00a9 2004 Elsevier Inc. Received 17 August 2004; revised 26 October 2004. Available online 21 January 2005. We thank M. Gerstell for a critical reading of the manuscript. This work was supported in part by an NSF grant and the NASA Astrobiology Institute at JPL.", "abstract": "The existence of methane in the martian atmosphere may be an indicator of subsurface life. Biological processes are known to fractionate the common isotopologues of methane, and hence measuring these isotopic ratios may yield constraints on the nature of the methane source. Any measurement of the isotopic ratios of atmospheric methane must consider the additional fractionation due to photochemistry in order to quantify the isotopic ratios of the source. Using a one-dimensional photochemical model, we find that photochemistry has a small (4.5\u2030) contribution to \u03b4^(13)C(CH_4) but has a large (114\u2030) contribution to \u03b4D(CH_4). Confirmation of these fractionation values will require additional laboratory data on key model inputs, particularly the ultraviolet absorption cross sections of ^(13)CH_4 and kinetic rate coefficients for the reactions of ^(13)CH_4 and CH_3D with OH and O(^1D) at pressures and temperatures relevant to the martian atmosphere.", "date": "2005-05", "date_type": "published", "publication": "Icarus", "volume": "175", "number": "1", "publisher": "Elsevier", "pagerange": "32-35", "id_number": "CaltechAUTHORS:20140826-094238444", "issn": "0019-1035", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140826-094238444", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF" }, { "agency": "NASA Astrobiology Institute" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/j.icarus.2004.10.018", "resource_type": "article", "pub_year": "2005", "author_list": "Nair, Hair; Summers, Michael E.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/xn0yy-0p563", "eprint_id": 48750, "eprint_status": "archive", "datestamp": "2023-08-22 03:14:24", "lastmod": "2023-10-17 20:24:10", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Esposito-L-W", "name": { "family": "Esposito", "given": "Larry W." } }, { "id": "Colwell-J-E", "name": { "family": "Colwell", "given": "Joshua E." } }, { "id": "Larsen-K", "name": { "family": "Larsen", "given": "Kristopher" } }, { "id": "McClintock-W-E", "name": { "family": "McClintock", "given": "William E." } }, { "id": "Stewart-A-I-F", "name": { "family": "Stewart", "given": "A. Ian F." } }, { "id": "Hallett-J-T", "name": { "family": "Hallett", "given": "Janet Tew" } }, { "id": "Shemansky-D-E", "name": { "family": "Shemansky", "given": "Donald E." }, "orcid": "0000-0001-7168-871X" }, { "id": "Ajello-J-M", "name": { "family": "Ajello", "given": "Joseph M." } }, { "id": "Hansen-C-J", "name": { "family": "Hansen", "given": "Candice J." } }, { "id": "Hendrix-A-R", "name": { "family": "Hendrix", "given": "Amanda R." } }, { "id": "West-R-A", "name": { "family": "West", "given": "Robert A." }, "orcid": "0000-0002-4320-2599" }, { "id": "Keller-H-U", "name": { "family": "Keller", "given": "H. Uwe" } }, { "id": "Korth-A", "name": { "family": "Korth", "given": "Axel" } }, { "id": "Pryor-W-R", "name": { "family": "Pryor", "given": "Wayne R." } }, { "id": "Reulke-R", "name": { "family": "Reulke", "given": "Ralf" } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Ultraviolet Imaging Spectroscopy shows an active saturnian system", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 2005 American Association for the Advancement of Science.\n\nReceived 23 September 2004; accepted 2 December 2004\nPublished online 16 December 2004.\n\nThanks to H. Tollerud for assistance with data\nprocessing, L. Bloom for producing the manuscript,\nand J. Cuzzi and the anonymous reviewers for helpful\ncomments. This work is one part of the Cassini UVIS\ninvestigation, supported by the NASA Jet Propulsion\nLaboratory Cassini mission.", "abstract": "Neutral oxygen in the saturnian system shows variability, and the total number of\noxygen atoms peaks at 4 x 10^(34). Saturn's aurora brightens in response to solar-wind\nforcing, and the auroral spectrum resembles Jupiter's. Phoebe's surface shows variable\nwater-ice content, and the data indicate it originated in the outer solar system.\nSaturn's rings also show variable water abundance, with the purest ice in the\noutermost A ring. This radial variation is consistent with initially pure water ice\nbombarded by meteors, but smaller radial structures may indicate collisional\ntransport and recent renewal events in the past 10^7 to 10^8 years.", "date": "2005-02-25", "date_type": "published", "publication": "Science", "volume": "307", "number": "5713", "publisher": "American Association for the Advancement of Science", "pagerange": "1251-1255", "id_number": "CaltechAUTHORS:20140820-160446094", "issn": "0036-8075", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140820-160446094", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA Cassini Mission" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1126/science.1105606", "resource_type": "article", "pub_year": "2005", "author_list": "Esposito, Larry W.; Colwell, Joshua E.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/hknxa-mce17", "eprint_id": 48861, "eprint_status": "archive", "datestamp": "2023-08-22 03:11:27", "lastmod": "2023-10-17 20:29:29", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Liang-Mao-Chang", "name": { "family": "Liang", "given": "Mao-Chang" }, "orcid": "0000-0002-5294-9344" }, { "id": "Lane-B-F", "name": { "family": "Lane", "given": "Benjamin F." } }, { "id": "Pappalardo-R-T", "name": { "family": "Pappalardo", "given": "Robert T." } }, { "id": "Allen-M-A", "name": { "family": "Allen", "given": "Mark" } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Atmosphere of Callisto", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2005 The American Geophysical Union.\n\nReceived 11 July 2004; Revised 17 October 2004; Accepted 1 December 2004; Published 8 February 2005.\n\nWe thank M. Gerstell, R. L. Shia, D. J. Stevenson, and D. F. Strobel for valuable discussions. This research was\nsupported in part by NASA grant NAG5-6263 to the California Institute of Technology. B.F.L. gratefully acknowledges the support of a Pappalardo Fellowship in Physics of MIT.\n\nPublished - jgre1905.pdf
Supplemental Material - jgre1905-sup-0001-tab01.txt
Supplemental Material - jgre1905-sup-0002-tab02.txt
", "abstract": "During the Galileo flybys of Callisto in 1999, a CO_2 atmosphere and an ionosphere were detected. Using the Caltech/Jet Propulsion Laboratory one-dimensional KINETICS model, we have successfully simulated the observed electron density within a factor of 2, while satisfying the observational constraints on carbon and oxygen atoms. We conclude that photoionization of CO_2 alone is insufficient to produce the observed electron density. An atmosphere 20\u2013100 times denser than the CO_2 atmosphere must be introduced, as suggested by Kliore et al. (2002). We show that an O_2-rich atmosphere is highly probable. However, the atomic oxygen produced from O_2 photodissociation is 2 orders of magnitude greater than the upper limit given by Strobel et al. (2002). The introduction of reactive hydrogen chemistry assuming a surface abundance of H_2O of \u223c2 \u00d7 10^9 cm^(\u22123) (4 \u00d7 10^(\u22128) mbar) is required to reduce the excess atomic O abundance. The calculated atomic O column density is >5 \u00d7 10^(12) cm^(\u22122), which is about the observed upper limit, suggesting we should be able to detect O in the atmosphere of Callisto.", "date": "2005-02-08", "date_type": "published", "publication": "Journal of Geophysical Research E", "volume": "110", "number": "E2", "publisher": "American Geophysical Union", "pagerange": "Art. No. E02003", "id_number": "CaltechAUTHORS:20140825-144257305", "issn": "0148-0227", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140825-144257305", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NAG5-6263" }, { "agency": "Pappalardo Fellowship in Physics" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2004JE002322", "primary_object": { "basename": "jgre1905.pdf", "url": "https://authors.library.caltech.edu/records/hknxa-mce17/files/jgre1905.pdf" }, "related_objects": [ { "basename": "jgre1905-sup-0001-tab01.txt", "url": "https://authors.library.caltech.edu/records/hknxa-mce17/files/jgre1905-sup-0001-tab01.txt" }, { "basename": "jgre1905-sup-0002-tab02.txt", "url": "https://authors.library.caltech.edu/records/hknxa-mce17/files/jgre1905-sup-0002-tab02.txt" } ], "resource_type": "article", "pub_year": "2005", "author_list": "Liang, Mao-Chang; Lane, Benjamin F.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/jxtmg-npp79", "eprint_id": 34155, "eprint_status": "archive", "datestamp": "2023-08-22 02:32:56", "lastmod": "2023-10-19 14:37:12", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Liang-Mao-Chang", "name": { "family": "Liang", "given": "Mao-Chang" }, "orcid": "0000-0002-5294-9344" }, { "id": "Blake-G-A", "name": { "family": "Blake", "given": "Geoffrey A." }, "orcid": "0000-0003-0787-1610" }, { "id": "Muller-R-P", "name": { "family": "Muller", "given": "Richard P." } }, { "id": "Miller-C-E", "name": { "family": "Miller", "given": "Charles E." }, "orcid": "0000-0002-9380-4838" } ] }, "title": "Evidence for O-atom exchange in the O(^1D) + N_2O reaction as the source of mass-independent isotopic fractionation in atmospheric N_2O", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2004 by the American Geophysical Union.\n\nReceived 7 July 2004; revised 21 August 2004; accepted 31 August 2004; published 8 October 2004.\n\nWe thank R.-L. Shia for helping to run the\n2-D model for N_2O and M. Gerstell, X. Jiang, and J. Kaiser for helpful\ndiscussions. We also thank the two referees for helpful comments. Special\nthanks are due M. H. Thiemens for sending us his data and for many\nilluminating conversations. This work was supported in part by NSF grant\nATM-9903790. The extension of the Caltech/JPL 2-D model to the\ntroposphere was supported by NASA ACMAP grant NAG1-1806. Sandia\nis a multiprogram laboratory operated by Sandia Corporation, a Lockheed\nMartin Company, for the United States Department of Energy under\nContract No. DE-AC04-94AL85000. RPM would like to thank Schrodinger,\nLLC, for use of the Jaguar program.\n\nPublished - 2004GL020950.pdf
", "abstract": "Recent experiments have shown that in the oxygen isotopic exchange reaction for O(^1D) + CO_2 the elastic channel is approximately 50% that of the inelastic channel [Perri et al., 2003]. We propose an analogous oxygen atom exchange reaction for the isoelectronic O(^1D) + N_2O system to explain the mass-independent isotopic fractionation (MIF) in atmospheric N_2O. We apply quantum chemical methods to compute the energetics of the potential energy surfaces on which the O(^1D) + N_2O reaction occurs. Preliminary modeling results indicate that oxygen isotopic exchange via O(^1D) + N_2O can account for the MIF oxygen anomaly if the oxygen atom isotopic exchange rate is 30\u201350% that of the total rate for the reactive channels.", "date": "2004-10-08", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "31", "number": "19", "publisher": "American Geophysical Union", "pagerange": "Art. No. L19106", "id_number": "CaltechAUTHORS:20120917-155609598", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20120917-155609598", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "ATM-9903790" }, { "agency": "NASA ACMAP", "grant_number": "NAG1-1806" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC04-94AL85000" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2004GL020950", "primary_object": { "basename": "2004GL020950.pdf", "url": "https://authors.library.caltech.edu/records/jxtmg-npp79/files/2004GL020950.pdf" }, "resource_type": "article", "pub_year": "2004", "author_list": "Yung, Yuk L.; Liang, Mao-Chang; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/9wrq3-dsh39", "eprint_id": 1133, "eprint_status": "archive", "datestamp": "2023-08-22 02:27:54", "lastmod": "2023-10-13 22:38:09", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Pernice-H", "name": { "family": "Pernice", "given": "Holger" } }, { "id": "Garcia-P", "name": { "family": "Garcia", "given": "Placido" } }, { "id": "Willner-H", "name": { "family": "Willner", "given": "Helge" } }, { "id": "Francisco-J-S", "name": { "family": "Francisco", "given": "Joseph S." } }, { "id": "Mills-F-P", "name": { "family": "Mills", "given": "Franklin P." } }, { "id": "Allen-M-A", "name": { "family": "Allen", "given": "Mark" } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Laboratory evidence for a key intermediate in the Venus atmosphere: Peroxychloroformyl radical", "ispublished": "pub", "full_text_status": "public", "keywords": "molecular-oxygen, photochemistry, spectra, planetary atmospheres, Venus", "note": "\u00a9 2004 by the National Academy of Sciences. \n\nCommunicated by Richard M. Goody, Harvard University, Boston, MA, July 29, 2004 (received for review May 20, 2004). Published online before print September 16, 2004, 10.1073/pnas.0405501101 \n\nWe thank M. F. Gerstell for a critical reading of the manuscript and W. DeMore, H. Hartman, C. Miller, C. Parkinson, V. Krasnopolsky, and the anonymous referees for useful comments. This research was supported partially by a Deutsche Forschungsgemeinschaft grant. This research was carried out in part at the Jet Propulsion Laboratory (California Institute of Technology) under contract to the National Aeronautics and Space Administration. J.S.F. expresses his thanks to the Alexander von Humboldt Foundation for a research grant for senior U.S. scientists.\n\nPublished - PERpnas04.pdf
", "abstract": "For two decades, the peroxychloroformyl radical, ClC(O)OO, has played a central role in models of the chemical stability of the Venus atmosphere. No confirmation, however, has been possible in the absence of laboratory measurements for ClC(O)OO. We report the isolation of ClC(O)OO in a cryogenic matrix and its infrared and ultraviolet spectral signatures. These experiments show that ClC(O)OO is thermally and photolytically stable in the Venus atmosphere. These experimental discoveries validate the existence of ClC(O)OO, confirm several longstanding model assumptions, and provide a basis for the astronomical search for this important radical species.", "date": "2004-09-28", "date_type": "published", "publication": "Proceedings of the National Academy of Sciences of the United States of America", "volume": "101", "number": "39", "publisher": "National Academy of Sciences", "pagerange": "14007-14010", "id_number": "CaltechAUTHORS:PERpnas04", "issn": "0027-8424", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:PERpnas04", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA/JPL/Caltech" }, { "agency": "Alexander von Humboldt Foundation" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1073/pnas.0405501101", "pmcid": "PMC521112", "primary_object": { "basename": "PERpnas04.pdf", "url": "https://authors.library.caltech.edu/records/9wrq3-dsh39/files/PERpnas04.pdf" }, "resource_type": "article", "pub_year": "2004", "author_list": "Pernice, Holger; Garcia, Placido; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/2ks2z-4w712", "eprint_id": 48775, "eprint_status": "archive", "datestamp": "2023-08-22 02:25:58", "lastmod": "2023-10-17 20:25:22", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Liao-T", "name": { "family": "Liao", "given": "Ting" } }, { "id": "Camp-C-D", "name": { "family": "Camp", "given": "Charles D." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "The seasonal cycle of N_2O", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2004 by the American Geophysical Union.\n\nReceived 23 April 2004; Revised 11 August 2004; Accepted 18 August 2004; Published 10 September 2004.\n\nWe thank X. Jiang and R.-L. Shia for running the 2D model for N2O and M. Gerstell and J. E. Elkins for helpful\ndiscussions. This work was supported in part by NSF grant ATM-9903790. The extension of the Caltech/JPL 2-D model to the troposphere was supported by NASA ACMAP grant NAG1-1806. T. Liao was partially supported by a grant from the Davidow Foundation.\n\nPublished - grl18536.pdf
", "abstract": "We have carried out an empirical study of the seasonal cycle of nitrous oxide (N_2O) using the data archived by the National Oceanic and Atmospheric Administration \u2013 Climate Monitoring and Diagnostics Laboratory (NOAA-CMDL) Global Cooperative Air Sampling Network from 1977 to 2000. In order to isolate the seasonal cycle, we first detrended the data using least square polynomial fits. The remaining variability was averaged to extract the seasonal cycle, which has an amplitude of about 0.8 ppbv. The statistical significance of the seasonal signal was established using the multitaper method and Welch's method for power spectrum analysis.", "date": "2004-09-10", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "31", "number": "17", "publisher": "American Geophysical Union", "pagerange": "Art. No. L17108", "id_number": "CaltechAUTHORS:20140821-113757339", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140821-113757339", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "ATM-9903790" }, { "agency": "NASA", "grant_number": "NAG1-1806" }, { "agency": "Davidow Foundation" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2004GL020345", "primary_object": { "basename": "grl18536.pdf", "url": "https://authors.library.caltech.edu/records/2ks2z-4w712/files/grl18536.pdf" }, "resource_type": "article", "pub_year": "2004", "author_list": "Liao, Ting; Camp, Charles D.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/2ysca-ptv63", "eprint_id": 48754, "eprint_status": "archive", "datestamp": "2023-08-22 02:15:03", "lastmod": "2023-10-17 20:24:27", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Jiang-Xun", "name": { "family": "Jiang", "given": "Xun" }, "orcid": "0000-0001-8932-3807" }, { "id": "Campl-C-D", "name": { "family": "Camp", "given": "Charles D." } }, { "id": "Shia-Run-Lie", "name": { "family": "Shia", "given": "Runlie" }, "orcid": "0000-0003-1911-3120" }, { "id": "Noone-D", "name": { "family": "Noone", "given": "David" } }, { "id": "Walker-C-C", "name": { "family": "Walker", "given": "Christopher" } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Quasi-biennial oscillation and quasi-biennial oscillation--annual beat in the tropical total column ozone: A two-dimensional model simulation", "ispublished": "pub", "full_text_status": "public", "keywords": "meridional circulation, Brewer-Dobson circulation, stratospheric ozone", "note": "\u00a9 2004 by the American Geophysical Union. Article first published online: 20 Aug 2004. Manuscript Accepted: 2 Jun 2004. Manuscript Revised: 24 Mar 2004. Manuscript Received: 24 Nov 2003. We thank T. Schneider for kindly giving us\nhis code for computing the stream function, E. Fleming for sending us his stream function, and K. K. Tung, V. Natraj, X. L. Huang, M. Gerstell, C. Parkinson, and two anonymous reviewers for helpful comments. This work was supported by NASA grant NAG1-1806.\n\nPublished - jgrd11147.pdf
", "abstract": "The National Centers for Environmental Prediction\u2013Department of Energy Reanalysis 2 data are used to calculate the monthly mean meridional circulation and eddy diffusivity from 1979 to 2002 for use in the California Institute of Technology\u2013Jet Propulsion Laboratory two-dimensional (2-D) chemistry and transport model (CTM). This allows for an investigation of the impact of dynamics on the interannual variability of the tropical total column ozone for all years for which the Total Ozone Mapping Spectrometer and the Solar Backscatter Ultraviolet merged total ozone data are available. The first two empirical orthogonal functions (EOFs) of the deseasonalized and detrended stratospheric stream function capture 88% of the total variance on interannual timescales. The first EOF, accounting for over 70% of the interannual variance, is related to the quasi-biennial oscillation (QBO) and its interaction with annual cycles, the QBO-annual beat (QBO-AB). The 2-D CTM provides realistic simulations of the seasonal and interannual variability of ozone in the tropics. The equatorial ozone anomaly from the model is close to that derived from the observations. The phase and amplitude of the QBO are well captured by the model. The magnitude of the QBO signal is somewhat larger in the model than it is in the data. The QBO-AB found in the simulated ozone agrees well with that in the observed data.", "date": "2004-08", "date_type": "published", "publication": "Journal of Geophysical Research D", "volume": "109", "number": "D16", "publisher": "American Geophysical Union", "pagerange": "Art. No. 16305", "id_number": "CaltechAUTHORS:20140821-071204784", "issn": "0148-0227", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140821-071204784", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NAG1-1806" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2003JD004377", "primary_object": { "basename": "jgrd11147.pdf", "url": "https://authors.library.caltech.edu/records/2ysca-ptv63/files/jgrd11147.pdf" }, "resource_type": "article", "pub_year": "2004", "author_list": "Jiang, Xun; Camp, Charles D.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/w59sm-vgm91", "eprint_id": 8907, "eprint_status": "archive", "datestamp": "2023-08-22 02:08:52", "lastmod": "2023-10-16 21:48:22", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Huang-X", "name": { "family": "Huang", "given": "Xianglei" } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk Ling" }, "orcid": "0000-0002-4263-2562" } ] }, "title": "A Common Misunderstanding about the Voigt Line Profile", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2004 American Meteorological Society. \n\nManuscript received 25 May 2003, in final form 25 December 2003", "abstract": "In this short note, a misinterpretation of the Voigt line profile is pointed out, which is in several popular textbooks of atmospheric physics. The correct interpretation is given based on mathematical and physical arguments, as well as numerical verification.", "date": "2004-07-01", "date_type": "published", "publication": "Journal of the Atmospheric Sciences", "volume": "61", "number": "13", "publisher": "American Meteorological Society", "pagerange": "1630-1632", "id_number": "CaltechAUTHORS:HUAjas04", "issn": "0022-4928", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:HUAjas04", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1175/1520-0469(2004)061<1630:ACMATV>2.0.CO;2", "primary_object": { "basename": "HUAjas04.pdf", "url": "https://authors.library.caltech.edu/records/w59sm-vgm91/files/HUAjas04.pdf" }, "resource_type": "article", "pub_year": "2004", "author_list": "Huang, Xianglei and Yung, Yuk Ling" }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/z7fj2-e0k14", "eprint_id": 48751, "eprint_status": "archive", "datestamp": "2023-08-22 02:01:13", "lastmod": "2023-10-17 20:24:15", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Ruzmaikin-A", "name": { "family": "Ruzmaikin", "given": "Alexander" } }, { "id": "Feynman-J", "name": { "family": "Feynman", "given": "Joan" } }, { "id": "Jiang-Xun", "name": { "family": "Jiang", "given": "Xun" }, "orcid": "0000-0001-8932-3807" }, { "id": "Noone-D-C", "name": { "family": "Noone", "given": "David C." } }, { "id": "Waple-A-M", "name": { "family": "Waple", "given": "Anne M." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "The pattern of northern hemisphere surface air temperature during prolonged periods of low solar output", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2004 American Geophysical Union.\n\nReceived 11 March 2004; revised 6 April 2004; accepted 14 April 2004; published 16 June 2004.\n\nThe images shown in Figure 1 are generated by using the NOAA- CIRES Climate Diagnostics Center web site. This\nwork was supported in part by the Jet Propulsion Laboratory of the California Institute of Technology, under a contract with NASA, and by the NASA LWS grant to the California Institute of Technology.\n\nPublished - grl18317.pdf
", "abstract": "We show that the reconstructed sensitivity of the sea level temperature to long term solar forcing in the Northern Hemisphere is in very good agreement with the empirical temperature pattern corresponding to changes of the North Annular Mode (NAM). This implies that long-term variations of solar output affect climate predominantly through the NAM that extends throughout the stratosphere and troposphere.", "date": "2004-06", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "31", "number": "12", "publisher": "American Geophysical Union", "pagerange": "Art. No. L12201", "id_number": "CaltechAUTHORS:20140820-161025214", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140820-161025214", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "JPL" }, { "agency": "NASA LWS" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2004GL019955", "primary_object": { "basename": "grl18317.pdf", "url": "https://authors.library.caltech.edu/records/z7fj2-e0k14/files/grl18317.pdf" }, "resource_type": "article", "pub_year": "2004", "author_list": "Ruzmaikin, Alexander; Feynman, Joan; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/5k4a7-yge23", "eprint_id": 34198, "eprint_status": "archive", "datestamp": "2023-08-22 01:58:24", "lastmod": "2023-10-19 14:43:53", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Liang-Mao-Chang", "name": { "family": "Liang", "given": "Mao-Chang" }, "orcid": "0000-0002-5294-9344" }, { "id": "Blake-G-A", "name": { "family": "Blake", "given": "Geoffrey A." }, "orcid": "0000-0003-0787-1610" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "A semianalytic model for photo-induced isotopic\n fractionation in simple molecules", "ispublished": "pub", "full_text_status": "public", "keywords": "0317 Atmospheric Composition and Structure: Chemical kinetic and\nphotochemical properties; 0341 Atmospheric Composition and Structure: Middle atmosphere\u2014constituent\ntransport and chemistry (3334); 3210 Mathematical Geophysics: Modeling; atmospheres,\nphotochemistry, stratosphere", "note": "\u00a9 2004 American Geophysical Union. \nReceived 14 January 2004; revised 29 March 2004; accepted 2 April 2004; published 26 May 2004. \nWe thank C. D. Camp, M. Gerstell, X. Jiang, V. Natraj, C. D. Parkinson, R. L. Shia, and J. D. Weibel for helpful comments and discussions. We also thank M. S. Johnson for sharing the ab initio calculation of N_2O's cross sections. This work was supported in part by an NSF grant ATM-9903790. The development of the Caltech/JPL 2-D model was supported by NASA grant NAG1-1806.\n\nPublished - 2004JD004539.pdf
", "abstract": "We have developed a semianalytic model for computing the photo-induced isotopic fractionation in simple molecules of interest to the atmospheric science community. The method is based on the Born-Oppenheimer approximation and the Reflection Principle. It has the main advantage of using commonly available input data, namely, the photolysis cross sections for the standard isotopologue/isotopomer and the ground state isotope-specific spectroscopic constants. The isotopic fractionation arises principally from the spectral shift induced by the small difference in zero point energy between isotopologues/isotopomers and the contraction of the wave function due to heavier isotope substitution. The latter effect dominates photolytic fractionation away from the cross section maxima. Our new approach is demonstrated with applications to the diatomic molecules HCl and HI, and the triatomic molecules N_2O and O_3. Agreement between the model and measurements is excellent. New modeling results for the fractionation of ^(15)N^(15)N^(16)O in the stratosphere using the Caltech/JPL two-dimensional model are presented.", "date": "2004-05-26", "date_type": "published", "publication": "Journal of Geophysical Research D", "volume": "109", "number": "D10", "publisher": "American Geophysical Union", "pagerange": "Art. No. D10308", "id_number": "CaltechAUTHORS:20120919-093705029", "issn": "0148-0227", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20120919-093705029", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "ATM-9903790" }, { "agency": "NASA", "grant_number": "NAG1-1806" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2004JD004539", "primary_object": { "basename": "2004JD004539.pdf", "url": "https://authors.library.caltech.edu/records/5k4a7-yge23/files/2004JD004539.pdf" }, "resource_type": "article", "pub_year": "2004", "author_list": "Liang, Mao-Chang; Blake, Geoffrey A.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/7nv0g-9yr07", "eprint_id": 48736, "eprint_status": "archive", "datestamp": "2023-08-22 01:49:08", "lastmod": "2023-10-17 20:23:25", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Liang-Mao-Chang", "name": { "family": "Liang", "given": "Mao-Chang" }, "orcid": "0000-0002-5294-9344" }, { "id": "Seager-S", "name": { "family": "Seager", "given": "Sara" }, "orcid": "0000-0002-6892-6948" }, { "id": "Parkinson-C-D", "name": { "family": "Parkinson", "given": "Christopher D." }, "orcid": "0000-0002-5722-2224" }, { "id": "Lee-Anthony-Y-T", "name": { "family": "Lee", "given": "Anthony Y.-T." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "On the Insignificance of Photochemical Hydrocarbon Aerosols in the Atmospheres of Close-in Extrasolar Giant Planets", "ispublished": "pub", "full_text_status": "public", "keywords": "planetary systems; radiative transfer; stars: atmospheres; stars: individual (HD 209458)", "note": "\u00a9 2004 American Astronomical Society.\n\nReceived 2003 November 20; accepted 2004 February 24; published 2004 March 16.\n\nWe thank M. Gerstell, J. McConnell, and R. L. Shia for\nhelpful discussions. We thank the anonymous referee for constructive comments. The support of NASA grant NAG5-6263\nto the California Institute of Technology is gratefully acknowledged. This material is also based on work supported by the National Aeronautics and Space Administration through the NASA Astrobiology Institute under Cooperative Agreement CAN-00-OSS-01 and NCC 2-1056 and issued through the Office of Space Science. S. S. is supported by the Carnegie Institution of Washington and by NASA Origins grant NAG5-13478.\n\nPublished - 1538-4357_605_1_L61.pdf
Submitted - 0402601v1.pdf
", "abstract": "The close-in extrasolar giant planets (CEGPs) reside in irradiated environments much more intense than that of the giant planets in our solar system. The high UV irradiance strongly influences their photochemistry, and the general current view believed that this high UV flux will greatly enhance photochemical production of hydrocarbon aerosols. In this Letter, we investigate hydrocarbon aerosol formation in the atmospheres of CEGPs. We find that the abundances of hydrocarbons in the atmospheres of CEGPs are significantly less than that of Jupiter except for models in which the CH4 abundance is unreasonably high (as high as CO) for the hot (effective temperatures \u22731000 K) atmospheres. Moreover, the hydrocarbons will be condensed out to form aerosols only when the temperature-pressure profiles of the species intersect with the saturation profiles\u2014a case almost certainly not realized in the hot CEGPs' atmospheres. Hence our models show that photochemical hydrocarbon aerosols are insignificant in the atmospheres of CEGPs. In contrast, Jupiter and Saturn have a much higher abundance of hydrocarbon aerosols in their atmospheres that are responsible for strong absorption shortward of 600 nm. Thus the insignificance of photochemical hydrocarbon aerosols in the atmospheres of CEGPs rules out one class of models with low albedos and featureless spectra shortward of 600 nm.", "date": "2004-04-10", "date_type": "published", "publication": "Astrophysical Journal Letters", "volume": "605", "number": "1", "publisher": "American Astronomical Society", "pagerange": "L61-L64", "id_number": "CaltechAUTHORS:20140820-133445176", "issn": "2041-8205", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140820-133445176", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NAG5-6263" }, { "agency": "NASA Astrobiology Institute", "grant_number": "CAN-00-OSS-01" }, { "agency": "NASA Astrobiology Institute", "grant_number": "NCC 2-1056" }, { "agency": "Carnegie Institution of Washington" }, { "agency": "NASA Origins", "grant_number": "NAG5-13478" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1086/392509", "primary_object": { "basename": "0402601v1.pdf", "url": "https://authors.library.caltech.edu/records/7nv0g-9yr07/files/0402601v1.pdf" }, "related_objects": [ { "basename": "1538-4357_605_1_L61.pdf", "url": "https://authors.library.caltech.edu/records/7nv0g-9yr07/files/1538-4357_605_1_L61.pdf" } ], "resource_type": "article", "pub_year": "2004", "author_list": "Liang, Mao-Chang; Seager, Sara; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/426w3-jbh68", "eprint_id": 48865, "eprint_status": "archive", "datestamp": "2023-08-22 01:41:01", "lastmod": "2023-10-17 20:29:42", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Jiang-Yibo", "name": { "family": "Jiang", "given": "Yibo" }, "orcid": "0000-0001-6711-7260" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Sander-S-P", "name": { "family": "Sander", "given": "Stan P." }, "orcid": "0000-0003-1424-3620" }, { "id": "Travis-L-D", "name": { "family": "Travis", "given": "Larry D." } } ] }, "title": "Modeling of atmospheric radiative transfer with polarization and its application to the remote sensing of tropospheric ozone", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 2003 Elsevier Ltd. Received 21 October 2002, Accepted 11 March 2003, Available online 21 November 2003. We would like to express our appreciation to Mark Allen, Richard Cageao and Andy Ingersoll for their valuable comments, and to Mimi Gerstell for a critical reading of the manuscript. This work\nwas supported in part by NASA grant NAGW 2204 to the California Institute of Technology and was carried out there and at JPL, under contract with NASA.", "abstract": "Light reflected or transmitted by a planetary atmosphere contains information about particles and molecules in the atmosphere. Therefore, accurate modeling of the radiation field may be used to retrieve information on atmospheric composition. In this paper, a multi-layer model for a vertically inhomogeneous atmosphere is implemented by using the doubling-adding method for a plane-parallel atmosphere. By studying the degree of linear polarization of the transmitted and reflected solar light in the Huggins bands, we find significant differences between tropospheric ozone and stratospheric ozone. The effects of tropospheric ozone change on the linear polarization are 10 times more than that of the same amount of stratospheric ozone change. We also show the aerosol effect on the linear polarization, but this effect is wavelength independent as compared to that caused by the tropospheric ozone change. The results provide a theoretical basis for the retrieval of tropospheric ozone from measurement of linear polarization of the scattered sunlight both from the ground and from a satellite.", "date": "2004-03-01", "date_type": "published", "publication": "Journal of Quantitative Spectroscopy and Radiative Transfer", "volume": "84", "number": "2", "publisher": "Elsevier", "pagerange": "169-179", "id_number": "CaltechAUTHORS:20140825-153132188", "issn": "0022-4073", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140825-153132188", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NAGW 2204" }, { "agency": "NASA/JPL/Caltech" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/S0022-4073(03)00140-7", "resource_type": "article", "pub_year": "2004", "author_list": "Jiang, Yibo; Yung, Yuk L.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/917ga-6pp59", "eprint_id": 34197, "eprint_status": "archive", "datestamp": "2023-08-22 01:34:21", "lastmod": "2023-10-19 14:43:50", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Morgan-C-G", "name": { "family": "Morgan", "given": "C. G." } }, { "id": "Allen-M-A", "name": { "family": "Allen", "given": "M." } }, { "id": "Liang-Mao-Chang", "name": { "family": "Liang", "given": "M. C." }, "orcid": "0000-0002-5294-9344" }, { "id": "Shia-Run-Lie", "name": { "family": "Shia", "given": "R. L." }, "orcid": "0000-0003-1911-3120" }, { "id": "Blake-G-A", "name": { "family": "Blake", "given": "G. A." }, "orcid": "0000-0003-0787-1610" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Y. L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Isotopic fractionation of nitrous oxide in the stratosphere: Comparison between model and observations", "ispublished": "pub", "full_text_status": "public", "keywords": "0315 Atmospheric Composition and Structure: Biosphere/atmosphere\ninteractions; 0341 Atmospheric Composition and Structure: Middle atmosphere\u2014constituent transport and\nchemistry (3334); 1040 Geochemistry: Isotopic composition/chemistry; 1610 Global Change: Atmosphere\n(0315, 0325); 1615 Global Change: Biogeochemical processes (4805); KEYWORDS: isotope, N2O, stratosphere", "note": "\u00a9 2004 American Geophysical Union. Received 10 January 2003; revised 17 September 2003; accepted 2 October 2003; published 20 February 2004. We thank D. Griffith for revised data, E. Fleming for sending us his stream functions, T. Rahn, M. Gerstell and S. Olsen for helpful comments, and R. Li for compiling the references. We\nthank two anonymous referees for painstakingly pointing out a number of inaccuracies in the early versions of this paper and for suggesting significant improvements of the paper. We especially thank the editor D. Toohey for his patience in guiding this paper through its reviews. This\nwork was supported in part by an NSF grant ATM-9903790. The updating of the Caltech/JPL 2-D model was supported by NASA grant NAG1-1806.\n\nPublished - 2003JD003402.pdf
", "abstract": "We investigate the mass dependent isotopic fractionation mechanisms, based on photolytic destruction and reaction with O^1D, to explain the ^(15)N/^(14)N and ^(18)O/^(16)O fractionation of stratospheric N_2O and reconcile laboratory experiments with atmospheric observations. The Caltech/JPL two-dimensional (2-D) model is utilized for detailed studies of N_2O and its isotopologues and isotopomers in the stratosphere. We compare model results with observations of isotopic enrichment using three different methods of calculating photolytic cross-sections for each of the major isotopologues and isotopomers of N_2O. Although the Yung and Miller [1997] successfully modeled the pattern of enrichments for each isotopologue or isotopomer relative to each other, their approach underestimated the magnitude of the enrichments. The ab initio approach by Johnson et al. [2001] provides a better fit to the magnitudes of the enrichments, with the notable exception of the enrichment for the ^(15)N^(14)N^(16)O. A simpler, semi-empirical approach by Blake et al. [2003] is able to model the magnitude of all the enrichments, including the one for ^(15)N^(14)N^(16)O. The Blake et al. [2003] cross-sections are temperature-dependent, but adjustments are needed to match the measurements of Kaiser et al. [2002a] . Using these modified cross-sections generally improves the agreement between model and mass spectrometric measurements. Destruction of N_2O by reaction with O(^1D) results in a small but nonnegligible isotopic fractionation in the lower stratosphere. On a per molecule basis, the rates of destruction of the minor isotopologues or isotopomers are somewhat less than that for ^(14)N^(14)N^(16)O. From our 2-D model we infer the relative rates for isotopologues and isotopomers ^(14)N^(14)N^(16)O (446), ^(14)N^(15)N^(16)O (456), ^(15)N^(14)N^(16)O (546), ^(14)N^(14)N^(17)O (447) and ^(14)N^(14)N^(18)O (448), to be 1, 0.9843, 0.9942, 0.9949, and 0.9900, respectively. Thus the destruction of N_2O in the atmosphere results in isotopic fractionations of (456), (546), (447) and (448) by 19.4, 9.5, 5.5 and 12.0\u2030. If we do not distinguish between the (456) and (546) isotopomers, the mean isotopic fractionation for ^(15)N is 14.5\u2030. If we assume that the mean tropospheric values for \u03b4_(456), \u03b4_(546_, \u03b4^(15)N and \u03b4^(18)O are 16.35, \u22122.35, 7.0 and 20.7\u2030, respectively, we infer the following isotopic signature for the integrated sources of N_2O: \u03b4_(456) = \u2212 2.9\u2030, \u03b4_(546) = \u221211.7\u2030, \u03b4^(15)N = \u22127.3\u2030 and \u03b4^(18)O = 8.7\u2030.", "date": "2004-02-20", "date_type": "published", "publication": "Journal of Geophysical Research D", "volume": "109", "number": "D4", "publisher": "American Geophysical Union", "pagerange": "Art. No. D04305", "id_number": "CaltechAUTHORS:20120919-091810000", "issn": "0148-0227", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20120919-091810000", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "ATM-9903790" }, { "agency": "NASA", "grant_number": "NAG1-1806" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2003JD003402", "primary_object": { "basename": "2003JD003402.pdf", "url": "https://authors.library.caltech.edu/records/917ga-6pp59/files/2003JD003402.pdf" }, "resource_type": "article", "pub_year": "2004", "author_list": "Morgan, C. G.; Allen, M.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/jprr2-z1394", "eprint_id": 48984, "eprint_status": "archive", "datestamp": "2023-08-22 01:25:09", "lastmod": "2023-10-17 20:35:26", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Esposito-L-W", "name": { "family": "Esposito", "given": "Larry W." } }, { "id": "Barth-C-A", "name": { "family": "Barth", "given": "Charles A." } }, { "id": "Colwell-J-E", "name": { "family": "Colwell", "given": "Joshua E." } }, { "id": "Lawrence-G-M", "name": { "family": "Lawrence", "given": "George M." } }, { "id": "McClintock-W-E", "name": { "family": "McClintock", "given": "William E." } }, { "id": "Stewart-A-I-F", "name": { "family": "Stewart", "given": "A. Ian F." } }, { "id": "Keller-H-U", "name": { "family": "Keller", "given": "H. Uwe" } }, { "id": "Korth-A", "name": { "family": "Korth", "given": "Axel" } }, { "id": "Lauche-H", "name": { "family": "Lauche", "given": "Hans" } }, { "id": "Festou-M-C", "name": { "family": "Festou", "given": "Michel C." } }, { "id": "Lane-A-L", "name": { "family": "Lane", "given": "Arthur L." } }, { "id": "Hansen-C-J", "name": { "family": "Hansen", "given": "Candice J." } }, { "id": "Maki-J-N", "name": { "family": "Maki", "given": "Justin N." } }, { "id": "West-R-A", "name": { "family": "West", "given": "Robert A." }, "orcid": "0000-0002-4320-2599" }, { "id": "Jahn-H", "name": { "family": "Jahn", "given": "Herbert" } }, { "id": "Reulke-R", "name": { "family": "Reulke", "given": "Ralf" } }, { "id": "Warlich-K", "name": { "family": "Warlich", "given": "Kerstin" } }, { "id": "Shemansky-D-E", "name": { "family": "Shemansky", "given": "Donald E." }, "orcid": "0000-0001-7168-871X" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "The Cassini Ultraviolet Imaging Spectrograph Investigation", "ispublished": "pub", "full_text_status": "restricted", "keywords": "Cassini, rings, Saturn, spectroscopy on Titan and on Saturn", "note": "\u00a9 2004 Kluwer Academic Publishers. \n\nReceived 8 July 1999; Accepted in final form 18 October 2000. \n\nThis work was supported by the National Aeronautics and Space Administration\nunder JPL Contract 961196. The Hydrogen Deuterium Absorption Cell (HDAC) was designed and constructed with support from the Max-Planck-Gesellschaft zur Foerderung der Wissenschaften. Grants were received from the DLR under FKZ 50 OH 9201 7. The authors thank Sushil Atreya and an anonymous reviewer for their helpful comments.\nThis revised version was published online in July 2005 with a corrected cover date.", "abstract": "The Cassini Ultraviolet Imaging Spectrograph (UVIS) is part of the remote sensing payload of the Cassini orbiter spacecraft. UVIS has two spectrographic channels that provide images and spectra covering the ranges from 56 to 118 nm and 110 to 190 nm. A third optical path with a solar blind CsI photocathode is used for high signal-to-noise-ratio stellar occultations by rings and atmospheres. A separate Hydrogen Deuterium Absorption Cell measures the relative abundance of deuterium and hydrogen from their Lyman-\u03b1 emission. The UVIS science objectives include investigation of the chemistry, aerosols, clouds, and energy balance of the Titan and Saturn atmospheres; neutrals in the Saturn magnetosphere; the deuterium-to-hydrogen (D/H) ratio for Titan and Saturn; icy satellite surface properties; and the structure and evolution of Saturn's rings.", "date": "2004-01", "date_type": "published", "publication": "Space Science Reviews", "volume": "115", "number": "1-4", "publisher": "Springer", "pagerange": "299-361", "id_number": "CaltechAUTHORS:20140827-103429198", "issn": "0038-6308", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140827-103429198", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "961196" }, { "agency": "DLR", "grant_number": "FKZ 50 OH 9201 7" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1007/s11214-004-1455-8", "resource_type": "article", "pub_year": "2004", "author_list": "Esposito, Larry W.; Barth, Charles A.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/a4mh2-x8f69", "eprint_id": 46592, "eprint_status": "archive", "datestamp": "2023-08-22 01:19:49", "lastmod": "2023-10-26 19:51:43", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Crisp-D", "name": { "family": "Crisp", "given": "D." }, "orcid": "0000-0002-4573-9998" }, { "id": "Randerson-J-T", "name": { "family": "Randerson", "given": "J. T." }, "orcid": "0000-0001-6559-7387" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Y. L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Kuang-Zhiming", "name": { "family": "Kuang", "given": "Z." } } ] }, "title": "The Orbiting Carbon Observatory (OCO) mission", "ispublished": "pub", "full_text_status": "restricted", "keywords": "Orbiting carbon observatory; Atmospheric carbon dioxide", "note": "\u00a9 2004 COSPAR. Published by Elsevier Ltd. Received 19 October 2002; received in revised form 5 April 2003; accepted 5 August 2003. Part of this work was performed for the Jet Propulsion Laboratory of the California Institute of Technology under contract to NASA. Significant contributions\nwere made by Hamilton Sundstrand Corporation (a United Technologies Company) and Orbital Sciences Corporation.", "abstract": "The Orbiting Carbon Observatory (OCO) mission will make the first global, space-based measurements of atmospheric carbon dioxide (CO_2) with the precision, resolution, and coverage needed to characterize CO_2 sources and sinks on regional scales. The measurement approach and instrument specifications were determined through an analysis of existing carbon cycle data and a series of observing system simulation experiments. During its 2-year mission, OCO will fly in a 1:15 PM sun-synchronous orbit with a 16-day ground-track repeat time, just ahead of the EOS Aqua platform. It will carry a single instrument that incorporates three bore-sighted high-resolution spectrometers designed to measure reflected sunlight in the 0.76-\u03bcm O_2 A-band and in the CO_2 bands at 1.61 and 2.06 \u03bcm. Soundings recorded in these three bands will be used to retrieve the column-averaged CO_2 dry air mole fraction (X_(CO)_2). A comprehensive validation program was included in the mission to ensure that the space-based X_(CO)_2 measurements have precisions of \u223c0.3% (1 ppm) on regional scales. OCO measurements will be used in global synthesis inversion and data assimilation models to quantify CO_2 sources and sinks. While OCO will have a nominal lifetime of only 2 years, it will serve as a pathfinder for future long-term CO_2 monitoring missions.", "date": "2004", "date_type": "published", "publication": "Advances in Space Research", "volume": "34", "number": "4", "publisher": "Elsevier", "pagerange": "700-709", "id_number": "CaltechAUTHORS:20140701-093514734", "issn": "0273-1177", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140701-093514734", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA/JPL/Caltech" }, { "agency": "Hamilton Sundstrand Corporation" }, { "agency": "Orbital Sciences Corporation" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/j.asr.2003.08.062", "resource_type": "article", "pub_year": "2004", "author_list": "Crisp, D.; Randerson, J. T.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/7075k-wtt17", "eprint_id": 48724, "eprint_status": "archive", "datestamp": "2023-08-22 01:16:54", "lastmod": "2023-10-17 20:22:48", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Mills-F-P", "name": { "family": "Mills", "given": "Franklin P." } }, { "id": "Cagaeo-R-P", "name": { "family": "Cageao", "given": "Richard P." } }, { "id": "Sander-S-P", "name": { "family": "Sander", "given": "Stanley P." }, "orcid": "0000-0003-1424-3620" }, { "id": "Allen-M-A", "name": { "family": "Allen", "given": "Mark" } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Remsberg-E-E", "name": { "family": "Remsberg", "given": "Ellis E." } }, { "id": "Russell-J-M-III", "name": { "family": "Russell", "given": "James M., III" } }, { "id": "Richter-U", "name": { "family": "Richter", "given": "Ulf" } } ] }, "title": "OH column abundance over Table Mountain Facility, California: Intra-annual variations and comparisons to model predictions for 1997\u20132001", "ispublished": "pub", "full_text_status": "public", "keywords": "hydroxyl; mesosphere; photochemistry", "note": "\u00a9 2003 The American Geophysical Union.\n\nReceived 4 February 2003; Revised 14 July 2003; Accepted 11 August 2003; Published 24 December 2003.\n\nThe research described in this paper was performed at the Jet Propulsion Laboratory, California Institute of Technology. Support received from the NASA Upper Atmosphere Research Program, the California Institute of Technology President's Fund, the Naval Research Laboratory, and NASA grants NAG1-1806 and NAG1-2151 to the California Institute of Technology is gratefully acknowledged. The authors thank Vassilli Nemtchinov and Yibo Jiang for their contributions to the collection and processing of the OH column measurements, Timothy Canty for his assistance in comparing the TMF and FPO measurements, and Fok-Yan Leung for assistance with the final versions of figures. Helpful\nsuggestions from an anonymous reviewer are gratefully acknowledged. The HALOE data were obtained via http://haloedata.larc.nasa.gov.\n\nPublished - jgrd10595.pdf
Supplemental Material - jgrd10595-sup-0001-README.txt
", "abstract": "Measurements of the OH column abundance over the Jet Propulsion Laboratory's Table Mountain Facility (TMF) have been made since July 1997 at 10\u00b0\u201380\u00b0 solar zenith angle using a Fourier transform ultraviolet spectrometer. The measured OH column at any solar zenith angle is typically larger in the afternoon than in the morning. The variations observed in the OH column abundance appear to result from changes in atmospheric conditions on a daily or longer timescale. The larger observed variations are statistically significant. Sensitivity coefficients describing how the OH column abundance is expected to change in response to changes in the concentrations of H_2O, O_3, NO, CO, and CH_4 have been calculated on the basis of an analytic model. On the basis of these sensitivity coefficients and Halogen Occultation Experiment observations of O_3, the net sensitivity of the OH column abundance to variations in O_3 should be close to zero. The observed OH column abundance over TMF increased by about 25% from July 1997 to December 2001. This interannual trend in OH column abundance is not consistent with calculations that incorporate observed trends in H_2O and O_3 and is at least a factor of 2 larger than the calculated difference between solar minimum and maximum. Comparisons between measured and calculated normalized OH column abundances suggest that the sensitivity of OH to variations in H_2O may be a factor of 2 larger than predicted in present models and that there is some other major driver for the observed variability in the OH column abundance that was not included in the present analysis.", "date": "2003-12-27", "date_type": "published", "publication": "Journal of Geophysical Research D", "volume": "108", "number": "D24", "publisher": "American Geophysical Union", "pagerange": "Art. No. 4785", "id_number": "CaltechAUTHORS:20140820-105110108", "issn": "0148-0227", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140820-105110108", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Caltech President's Fund" }, { "agency": "Naval Research Laboratory" }, { "agency": "NASA", "grant_number": "NAG1-1806" }, { "agency": "NASA", "grant_number": "NAG1-2151" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2003JD003481", "primary_object": { "basename": "jgrd10595-sup-0001-README.txt", "url": "https://authors.library.caltech.edu/records/7075k-wtt17/files/jgrd10595-sup-0001-README.txt" }, "related_objects": [ { "basename": "jgrd10595.pdf", "url": "https://authors.library.caltech.edu/records/7075k-wtt17/files/jgrd10595.pdf" } ], "resource_type": "article", "pub_year": "2003", "author_list": "Mills, Franklin P.; Cageao, Richard P.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/q5aqx-bba64", "eprint_id": 35086, "eprint_status": "archive", "datestamp": "2023-08-22 01:08:14", "lastmod": "2023-10-20 15:19:59", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Eiler-J-M", "name": { "family": "Eiler", "given": "John M." } }, { "id": "Tromp-T-K", "name": { "family": "Tromp", "given": "Tracey K." } }, { "id": "Shia-Run-Lie", "name": { "family": "Shia", "given": "Run-Lie" }, "orcid": "0000-0003-1911-3120" }, { "id": "Allen-M-A", "name": { "family": "Allen", "given": "Mark" } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "The Bush Administration and hydrogen - Response", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 2003 American Association for the Advancement of Science.", "abstract": "Garman argues, correctly, that if people\nmake very little molecular hydrogen, then\nvery little can leak into the atmosphere.\nHowever, he considers only the 53 megatons\nof annual hydrogen production\nrequired for a single program in a single\ncountry\u2014one or two orders of magnitude\nsmaller than the scale a future hydrogen\neconomy must take if it is to significantly\nimpact global fossil fuel use.", "date": "2003-11-21", "date_type": "published", "publication": "Science", "volume": "302", "number": "5649", "publisher": "American Association for the Advancement of Science", "pagerange": "1332-1333", "id_number": "CaltechAUTHORS:20121025-093430710", "issn": "0036-8075", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20121025-093430710", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1126/science.302.5649.1331", "resource_type": "article", "pub_year": "2003", "author_list": "Eiler, John M.; Tromp, Tracey K.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/94nnx-qy915", "eprint_id": 47427, "eprint_status": "archive", "datestamp": "2023-08-22 01:01:38", "lastmod": "2023-10-26 20:35:17", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Camp-C-D", "name": { "family": "Camp", "given": "Charles D." } }, { "id": "Roulston-M-S", "name": { "family": "Roulston", "given": "Mark S." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Temporal and spatial patterns of the interannual variability of total ozone in the tropics", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2003 The American Geophysical Union.\n\nReceived 25 October 2001; Revised 29 July 2002; Accepted 20 December 2002; Published 25 October 2003.\n\nWe thank M. Allen, D. Noone, S. Leroy,P. Wennberg, A. Ingersoll, T. Schneider, A. Gould, Z. Kuang, X. Huang and\nthree anonymous reviewers for helpful comments, and R. Stolarski of NASA Goddard Space Flight Center for the use of O_3 data from the merged ozone data set. Supported by NASA grants NAG5-10901 and NAG1-2081 to the California Institute of Technology.\n\nPublished - jgrd9496.pdf
", "abstract": "The recently constructed gridded Merged Ozone Data (MOD) set, combining the monthly mean column abundances collected by the Total Ozone Mapping Spectrometer (TOMS) and the Solar Backscatter Ultraviolet (SBUV and SBUV/2) instruments, provides a nearly continuous record from late 1978 to 2000 on a 5\u00b0 \u00d7 10\u00b0 latitude-longitude grid. The precision of these measurements and their calibration allow very small signals, \u223c1% of total column ozone, to be clearly seen. Using MOD, we have carried out an empirical orthogonal function (EOF) study of the temporal and spatial patterns of the interannual variability of total column ozone in the tropics. The first four EOFs of our study capture over 93% of the variance of the deseasonalized data. The leading two EOFs of our study, respectively accounting for 42% and 33% of the variance, display structures attributable to the quasi-biennial oscillation(QBO), with influence from a decadal oscillation. The third EOF (15% of the variance) represents an interaction between the QBO and an annual cycle. The fourth EOF (3% of the variance) is related to the El Ni\u00f1o - Southern Oscillation. This EOF decomposition is robust; nearly identical patterns occur in the decomposition of various equatorial latitude bands of MOD and similar patterns occur in the analysis of the deseasonalized TOMS data set, a shorter record with a more finely resolved spatial grid. For comparison, similar decompositions were performed for dynamical fields from the reanalysis product from the National Centers for Environmental Prediction and the National Center for Atmospheric Research. Using these analyses, we found possible connections between the deduced patterns in ozone and the climate variables.", "date": "2003-10-27", "date_type": "published", "publication": "Journal of Geophysical Research D", "volume": "108", "number": "D20", "publisher": "American Geophysical Union", "pagerange": "Art. No. 4643", "id_number": "CaltechAUTHORS:20140723-115608347", "issn": "0148-0227", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140723-115608347", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NAG5-10901" }, { "agency": "NASA", "grant_number": "NAG1-2081" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2001JD001504", "primary_object": { "basename": "jgrd9496.pdf", "url": "https://authors.library.caltech.edu/records/94nnx-qy915/files/jgrd9496.pdf" }, "resource_type": "article", "pub_year": "2003", "author_list": "Camp, Charles D.; Roulston, Mark S.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/7zg2g-pfx77", "eprint_id": 48951, "eprint_status": "archive", "datestamp": "2023-08-22 01:01:01", "lastmod": "2023-10-17 20:34:08", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Liang-Mao-Chang", "name": { "family": "Liang", "given": "Mao-Chang" }, "orcid": "0000-0002-5294-9344" }, { "id": "Parkinson-C-D", "name": { "family": "Parkinson", "given": "Christopher D." }, "orcid": "0000-0002-5722-2224" }, { "id": "Lee-Anthony-Y-T", "name": { "family": "Lee", "given": "Anthony Y. T." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Seager-S", "name": { "family": "Seager", "given": "Sara" }, "orcid": "0000-0002-6892-6948" } ] }, "title": "Source of atomic hydrogen in the atmosphere of HD 209458b", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2003 The American Astronomical Society.\n\nReceived 2003 June 27; accepted 2003 August 28; published 2003 September 18.\n\nWe thank M. Gerstell, J. C. McConnell, R. L. Shia, and the\nreferee D. Homeier for helpful comments. This work was supported by NASA grant NAG5-6263 and the Astrobiology program\nat JPL.\n\nPublished - 1538-4357_596_2_L247.pdf
Submitted - 0307037v1.pdf
", "abstract": "Atomic hydrogen loss at the top of HD 209458b's atmosphere has been recently suggested (Vidal-Madjar et al.). We have developed a one-dimensional model to study the chemistry in the upper atmosphere of this extrasolar \"hot Jupiter.\" The three most abundant elements (other than He) as well as four parent molecules are included in this model, viz., H, C, O, H_2, CO, H_2O, and CH_4. The higher temperatures (~1000 K) and higher stellar irradiance (~6 \u00d7 10^5 W m^-2) strongly enhance and modify the chemical reaction rates in this atmosphere. The main result is that the production of atomic hydrogen in the atmosphere is mainly driven by H_2O photolysis, and the reaction of OH with H_2, and is insensitive to the exact abundances of CO, H_2O, and CH_4. For comparison, the bulk H concentration for \"hot Jupiters\" is 3 orders of magnitude higher than that of Jupiter.", "date": "2003-10-20", "date_type": "published", "publication": "Astrophysical Journal Letters", "volume": "596", "number": "2", "publisher": "American Astronomical Society", "pagerange": "L247-L250", "id_number": "CaltechAUTHORS:20140826-160824682", "issn": "2041-8205", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140826-160824682", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NAG5-6263" }, { "agency": "NASA Astrobiology Institute" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1086/379314", "primary_object": { "basename": "0307037v1.pdf", "url": "https://authors.library.caltech.edu/records/7zg2g-pfx77/files/0307037v1.pdf" }, "related_objects": [ { "basename": "1538-4357_596_2_L247.pdf", "url": "https://authors.library.caltech.edu/records/7zg2g-pfx77/files/1538-4357_596_2_L247.pdf" } ], "resource_type": "article", "pub_year": "2003", "author_list": "Liang, Mao-Chang; Parkinson, Christopher D.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/wx1ah-h3v40", "eprint_id": 35089, "eprint_status": "archive", "datestamp": "2023-09-14 19:38:35", "lastmod": "2023-10-23 20:54:05", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Eiler-J-M", "name": { "family": "Eiler", "given": "John M." } }, { "id": "Tromp-T-K", "name": { "family": "Tromp", "given": "Tracey K." } }, { "id": "Shia-Run-Lie", "name": { "family": "Shia", "given": "Run-Lie" }, "orcid": "0000-0003-1911-3120" }, { "id": "Allen-M-A", "name": { "family": "Allen", "given": "Mark" } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Y. L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Assessing the Future Hydrogen Economy - Response", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 2003 American Association for the Advancement of Science.", "abstract": "The letter writers suggest that\nemissions of H_2 associated with a hydrogen\neconomy could not be as large as the upper\nend of the range we consider. We have two\nresponses.", "date": "2003-10-10", "date_type": "published", "publication": "Science", "volume": "302", "number": "5643", "publisher": "American Association for the Advancement of Science", "pagerange": "228-229", "id_number": "CaltechAUTHORS:20121025-094147272", "issn": "0036-8075", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20121025-094147272", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1126/science.302.5643.226a", "resource_type": "article", "pub_year": "2003", "author_list": "Eiler, John M.; Tromp, Tracey K.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/pnevy-3b749", "eprint_id": 48758, "eprint_status": "archive", "datestamp": "2023-08-22 00:59:05", "lastmod": "2023-10-17 20:24:41", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Huang-Xianglei", "name": { "family": "Huang", "given": "Xianglei" }, "orcid": "0000-0002-7129-614X" }, { "id": "Liu-Junjun", "name": { "family": "Liu", "given": "Junjun" } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Analysis of Thermal Emission Spectrometer data using spectral EOF and tri-spectral methods", "ispublished": "pub", "full_text_status": "restricted", "keywords": "Mars, atmosphere; Radiative transfer; Atmosphere, structure", "note": "\u00a9 2003 Elsevier Inc. Received 12 February 2003; revised 20 May 2003. Available online 26 August 2003. We thank S. Byrne, M. Gerstell, A. Ingersoll, T. Martin, and M. Richardson for helpful discussions. We are greatly indebted to M. Richardson for his help in accessing TES data. One of the authors, Y.L. Yung, is indebted to T. Martin for pointing out the importance of anisothermality. We also thank two referees, including J.L. Bandfield for greatly improving the paper. This research was supported by NASA grant NAGS-10724 to the California Institute of Technology.", "abstract": "We introduce two new techniques in analyzing martian spectrally resolved radiance data obtained by the Thermal Emission Spectrometer (TES): spectral empirical orthogonal function (EOF) analysis and the tri-spectral algorithm. Spectral EOF analysis allows us to obtain the variability of spectra and associated temporal and spatial patterns. The case study with TES 20\u00b0 S\u201320\u00b0 N data shows that the first principal component (PC1) dominates the total variance and is associated with surface or near-surface brightness temperature variations. The PC2 is associated with atmospheric variability, and a negative correlation between dust and ice absorptions can be clearly seen over many regions. The annual cycle is a major component of the PC1 temporal patterns. The fingerprint of the dust storm can be clearly seen in the PC2 temporal patterns in most areas except the highlands. Spectral EOF can be used for validation of the variability of martian GCMs. The tri-spectral algorithm is based on the differences between three bands (dust, ice and a weak CO_2 absorption band) to distinguish spectra sampled in different situations: water ice cloud, dust, and surface anisothermality. We use a line-by-line radiative transfer model coupled with multiple scattering to investigate the sensitivity of this algorithm to dust and ice optical depth as well as surface emissivity. The comparisons between results of this algorithm and the TES team's retrieved dust and ice opacity are consistent over all studied periods except during the peak of the dust storm. Our algorithm is complementary to the more sophisticated TES retrieval and can be used to screen large amounts of data to get an overview.", "date": "2003-10", "date_type": "published", "publication": "Icarus", "volume": "165", "number": "2", "publisher": "Elsevier", "pagerange": "301-314", "id_number": "CaltechAUTHORS:20140821-083410505", "issn": "0019-1035", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140821-083410505", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NAGS-10724" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/S0019-1035(03)00206-9", "resource_type": "article", "pub_year": "2003", "author_list": "Huang, Xianglei; Liu, Junjun; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/19nsg-8jp85", "eprint_id": 48715, "eprint_status": "archive", "datestamp": "2023-08-22 00:40:35", "lastmod": "2023-10-17 20:22:24", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Leroy-S-S", "name": { "family": "Leroy", "given": "S. S." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Y. L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Richardson-M-I", "name": { "family": "Richardson", "given": "M. I." } }, { "id": "Wilson-R-J", "name": { "family": "Wilson", "given": "R. J." } } ] }, "title": "Principal modes of variability of Martian atmospheric surface pressure", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2003 American Geophysical Union.\n\nReceived 18 July 2002; revised 30 December 2002; accepted 7 January 2003; published 11 July 2003.\n\nS. S. Leroy was supported by a grant from the program Living with a Star of NASA's Office of Space Science. Y. L.\nYung was supported by NASA's Mars Data Analysis Program. The work benefitted from discussions with C. David Camp. It was done in part at the Jet Propulsion Laboratory of the California Institute of Technology.\n\nPublished - grl16261.pdf
", "abstract": "An analysis of daily-to-interannual variability in the surface pressure field of the Martian northern hemisphere as given by a Martian climate model is presented. In an empirical orthogonal function (EOF) decomposition, the dominant first two modes of variability comprise a zonal wavenumber 1 feature centered at 70 N latitude moving eastward with a period of 6 to 8 sols. This feature is a baroclinic wave and accounts for 53% of the northern hemisphere non-stationary surface pressure variability, and, when active, has an amplitude of up to 2% of local surface pressure. The third mode of the EOF decomposition is annular about the Martian north pole, is null southward of 70 N, and accounts for 7% of the northern hemisphere non-stationary surface pressure variability. The baroclinic wave (EOFs 1 & 2) is active during northern hemisphere winter and spring, consistent with models of the Martian atmospheric circulation, and the annular mode (EOF 3) is active only at the onset and demise of the baroclinic feature. When active, it is not uncommon for the annular mode to reside in either its positive or negative state stably for 20 to 30 sols. It is postulated that baroclinic waves with longitudinal wavenumber 2, 3, and 4 act as a pump for the annular mode. The annular mode should not be present in MGS TES data.", "date": "2003-07", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "30", "number": "13", "publisher": "American Geophysical Union", "pagerange": "Art. No. 1707", "id_number": "CaltechAUTHORS:20140820-085854408", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140820-085854408", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA Office of Space Science" }, { "agency": "NASA Mars Data Analysis Program" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2002GL015909", "primary_object": { "basename": "grl16261.pdf", "url": "https://authors.library.caltech.edu/records/19nsg-8jp85/files/grl16261.pdf" }, "resource_type": "article", "pub_year": "2003", "author_list": "Leroy, S. S.; Yung, Y. L.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/6aaz1-zv463", "eprint_id": 34196, "eprint_status": "archive", "datestamp": "2023-08-22 00:38:37", "lastmod": "2023-10-19 14:43:46", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Blake-G-A", "name": { "family": "Blake", "given": "Geoffrey A." }, "orcid": "0000-0003-0787-1610" }, { "id": "Liang-Mao-Chang", "name": { "family": "Liang", "given": "Mao-Chang" }, "orcid": "0000-0002-5294-9344" }, { "id": "Morgan-C-G", "name": { "family": "Morgan", "given": "Crristopher G." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "A Born-Oppenheimer photolysis model of N_2O fractionation", "ispublished": "pub", "full_text_status": "public", "keywords": "0317 Atmospheric Composition and Structure: Chemical\nkinetic and photochemical properties; 0322 Atmospheric\nComposition and Structure: Constituent sources and sinks.", "note": "\u00a9 2003 American Geophysical Union. Received 15 January 2003; revised 21 March 2003; accepted 9 April 2003; published 28 June 2003. This work was supported by the Atmospheric Chemistry program of the NSF (ATM99-03790; YLY, PI). Additional NASA support to GAB is gratefully acknowledged.\n\nPublished - 2003GL016932.pdf
", "abstract": "The isotopically light N_2O produced by microbial activity is thought to be balanced by the return of heavy stratospheric nitrous oxide. The Yung and Miller [1997] method that first explained these trends yields photolytic fractionation factors \u223chalf those observed by experiment or predicted quantum mechanically, however. To address these issues, we present here a Born-Oppenheimer photolysis model that uses only commonly available spectroscopic data. The predicted fractionations quantitatively reproduce laboratory data, and have been incorporated into zonally averaged atmospheric simulations. Like McLinden et al. [2003] , who employ a three-dimensional chemical transport model with cross sections scaled to match laboratory data, we find excellent agreement between predictions and stratospheric measurements; additional processes that contribute to the mass independent anomaly in N_2O can only account for a fraction of its global budget.", "date": "2003-06-28", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "30", "number": "12", "publisher": "American Geophysical Union", "pagerange": "Art. No. 1656", "id_number": "CaltechAUTHORS:20120919-090835144", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20120919-090835144", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "ATM99-03790" }, { "agency": "NASA" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2003GL016932", "primary_object": { "basename": "2003GL016932.pdf", "url": "https://authors.library.caltech.edu/records/6aaz1-zv463/files/2003GL016932.pdf" }, "resource_type": "article", "pub_year": "2003", "author_list": "Blake, Geoffrey A.; Liang, Mao-Chang; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/n2h3z-xt747", "eprint_id": 35700, "eprint_status": "archive", "datestamp": "2023-08-22 00:36:50", "lastmod": "2023-10-20 20:30:18", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Tromp-T-K", "name": { "family": "Tromp", "given": "Tracey K." } }, { "id": "Shia-Run-Lie", "name": { "family": "Shia", "given": "Run-Lie" }, "orcid": "0000-0003-1911-3120" }, { "id": "Allen-M-A", "name": { "family": "Allen", "given": "Mark" } }, { "id": "Eiler-J-M", "name": { "family": "Eiler", "given": "John M." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Y. L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Potential Environmental Impact of a Hydrogen Economy on the Stratosphere", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 2003 American Association for the Advancement of Science.\n\nReceived for publication 1 April 2003; Accepted for publication 15 May 2003.\n\nWe thank P. de Forster for sending us temperature data from his model, D. C. Noone for valuable discussions, and M. F. Gerstell for a critical reading of the manuscript. Supported in part by NASA grant NAG1-02081 and by a research grant to J.M.E. from General Motors.", "abstract": "The widespread use of hydrogen fuel cells could have hitherto unknown environmental impacts due to unintended emissions of molecular hydrogen, including an increase in the abundance of water vapor in the stratosphere (plausibly by as much as \u223c1 part per million by volume). This would cause stratospheric cooling, enhancement of the heterogeneous chemistry that destroys ozone, an increase in noctilucent clouds, and changes in tropospheric chemistry and atmosphere-biosphere interactions.", "date": "2003-06-13", "date_type": "published", "publication": "Science", "volume": "300", "number": "5626", "publisher": "American Association for the Advancement of Science", "pagerange": "1740-1742", "id_number": "CaltechAUTHORS:20121128-100102187", "issn": "0036-8075", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20121128-100102187", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NAG1-02081" }, { "agency": "General Motors" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1126/science.1085169", "resource_type": "article", "pub_year": "2003", "author_list": "Tromp, Tracey K.; Shia, Run-Lie; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/aj4wk-b4x43", "eprint_id": 3887, "eprint_status": "archive", "datestamp": "2023-08-23 23:25:03", "lastmod": "2023-10-16 16:12:26", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Stein-L-Y", "name": { "family": "Stein", "given": "Lisa Y." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Production, isotopic composition, and atmospheric fate of biologically produced nitrous oxide", "ispublished": "pub", "full_text_status": "public", "keywords": "microorganisms; isotopic discrimination; photolysis; greenhouse gas; global budget", "note": "\u00a9 2003 by Annual Reviews. \n\nFirst Published online as a Review in Advance on January 8, 2003. \n\nWe thank J. Tung, K. Campbell, H.J. Chiang, and F.L. Jordan for helpful comments. This work was supported in part by an NSF grant and a grant from the Davidow Foundation.\n\nPublished - STEareps03.pdf
", "abstract": "The anthropogenic production of greenhouse gases and their consequent effects on global climate have garnered international attention for years. A remaining challenge facing scientists is to unambiguously quantify both sources and sinks of targeted gases. Microbiological metabolism accounts for the largest source of nitrous oxide (N\u2082O), mostly due to global conversion of land for agriculture and massive usage of nitrogen-based fertilizers. A most powerful method for characterizing the sources of N\u2082O lies in its multi-isotope signature. This review summarizes mechanisms that lead to biological N\u2082O production and how discriminate placement of \u00b9\u2075N into molecules of N\u2082O occurs. Through direct measurements and atmospheric modeling, we can now place a constraint on the isotopic composition of biological sources of N\u2082O and trace its fate in the atmosphere. This powerful interdisciplinary combination of biology and atmospheric chemistry is rapidly advancing the closure of the global N\u2082O budget.", "date": "2003-05", "date_type": "published", "publication": "Annual Review of Earth and Planetary Sciences", "volume": "31", "publisher": "Annual Reviews", "pagerange": "329-356", "id_number": "CaltechAUTHORS:STEareps03", "issn": "0084-6597", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:STEareps03", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF" }, { "agency": "Davidow Foundation" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1146/annurev.earth.31.110502.080901", "primary_object": { "basename": "STEareps03.pdf", "url": "https://authors.library.caltech.edu/records/aj4wk-b4x43/files/STEareps03.pdf" }, "resource_type": "article", "pub_year": "2003", "author_list": "Stein, Lisa Y. and Yung, Yuk L." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/wazxz-yw030", "eprint_id": 6797, "eprint_status": "archive", "datestamp": "2023-08-23 23:25:27", "lastmod": "2023-10-16 20:32:33", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Huang-X-L", "name": { "family": "Huang", "given": "Xianglei L." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Margolis-J-S", "name": { "family": "Margolis", "given": "Jack S." } } ] }, "title": "Use of high-resolution measurements for the retrieval of temperature and gas-concentration profiles from outgoing infrared spectra in the presence of cirrus clouds", "ispublished": "pub", "full_text_status": "public", "keywords": "Numerical approximation and analysis; Atmospheric scattering; Meteorology", "note": "\u00a9 2003 Optical Society of America. Received 21 August 2002; revised manuscript received 2 January 2003. \n\nWe thank M. Gerstell and Z.M. Kuang for valuable comments. We also thank two anonymous referees for improving the paper. This research is supported by NOAA grant NA06EC0505 to the California Institute of Technology.", "abstract": "We explore ways in which high-spectral-resolution measurements can aid in the retrieval of atmospheric temperature and gas-concentration profiles from outgoing infrared spectra when optically thin cirrus clouds are present. Simulated outgoing spectra that contain cirrus are fitted with spectra that do not contain cirrus, and the residuals are examined. For those lines with weighting functions that peak near the same altitude as the thin cirrus, unique features are observed in the residuals. These unique features are highly sensitive to the resolution of the instrumental line shape. For thin cirrus these residual features are narrow (\u22640.1 cm-1), so high spectral resolution is required for unambiguous observation. The magnitudes of these unique features are larger than the noise of modern instruments. The sensitivities of these features to cloud height and cloud optical depth are also discussed. Our sensitivity studies show that, when the errors in the estimation of temperature profiles are not large, the dominant contribution to the residuals is the misinterpretation of cirrus. An analysis that focuses on information content is also presented. An understanding of the magnitude of the effect and of its dependence on spectral resolution as well as on spectral region is important for retrieving spacecraft data and for the design of future infrared instruments for forecasting weather and monitoring greenhouse gases.", "date": "2003-04-20", "date_type": "published", "publication": "Applied Optics", "volume": "42", "number": "12", "publisher": "Optical Society of America", "pagerange": "2155-2165", "id_number": "CaltechAUTHORS:HUAao03", "issn": "0003-6935", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:HUAao03", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "primary_object": { "basename": "HUAao03.pdf", "url": "https://authors.library.caltech.edu/records/wazxz-yw030/files/HUAao03.pdf" }, "resource_type": "article", "pub_year": "2003", "author_list": "Huang, Xianglei L.; Yung, Yuk L.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/0z9pc-wn968", "eprint_id": 46586, "eprint_status": "archive", "datestamp": "2023-08-23 23:46:30", "lastmod": "2023-10-26 19:51:24", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Kuang-Zhiming", "name": { "family": "Kuang", "given": "Zhiming" } }, { "id": "Toon-G-C", "name": { "family": "Toon", "given": "Geoffrey C." }, "orcid": "0000-0003-4174-7541" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Measured HDO/H_2O ratios across the tropical tropopause", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2003 American Geophysical Union. \n\nReceived 30 January 2003; revised 28 February 2003; accepted 7 March 2003; published 4 April 2003. \n\nWe thank M. L. Salby for providing the 3-hourly 11-\u00b5m brightness temperature data, M. R. Gunson and the ATMOS science team for the acquisition and processing of the ATLAS-3 spectra, and F.W. Irion and B. Sen for help with accessing them. We thank R. A. Toth for making available water vapor spectroscopic parameters prior to their publication, and E. J. Moyer, S. C. Sherwood, A. E. Dessler for helpful discussions.\n\nPublished - grl16822.pdf
", "abstract": "We present the first simultaneous measurements of HDO and H_2O in the tropical upper troposphere (UT) and lower stratosphere (LS) as derived from infrared solar absorption spectra acquired by the Atmospheric Trace Molecule Spectroscopy (ATMOS) experiment. We find, surprisingly, that the observed HDO/H_2O ratio does not decrease with altitude in this region despite a factor of 4\u20135 decrease in the water vapor mixing ratio. This observation is inconsistent with the view that dehydration in the tropical UT/LS is by gradual processes, and suggests a major role by convective processes.", "date": "2003-04-04", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "30", "number": "7", "publisher": "American Geophysical Union", "pagerange": "Art. No. 1372", "id_number": "CaltechAUTHORS:20140701-074011166", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140701-074011166", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2003GL017023", "primary_object": { "basename": "grl16822.pdf", "url": "https://authors.library.caltech.edu/records/0z9pc-wn968/files/grl16822.pdf" }, "resource_type": "article", "pub_year": "2003", "author_list": "Kuang, Zhiming; Toon, Geoffrey C.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/4e2gp-t4y17", "eprint_id": 48718, "eprint_status": "archive", "datestamp": "2023-08-23 23:47:20", "lastmod": "2023-10-17 20:22:32", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Wong-A-S", "name": { "family": "Wong", "given": "Ah-San" } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Friedson-A-J", "name": { "family": "Friedson", "given": "A. James" } } ] }, "title": "Benzene and Haze Formation in the Polar Atmosphere of Jupiter", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2003 American Geophysical Union.\n\nReceived 24 November 2002; revised 17 March 2003; accepted 24 March 2003; published 30 April 2003.\n\nWe thank V. G. Anicich and K. Bayes for helpful comments of the kinetics, S. K. Atreya for discussion on eddy mixing, T. Majeed and D. Grodent for providing model atmosphere data\nand ion production rates, M. F. Gerstell for a critical reading of an earlier version of the manuscript, and S. K. Atreya, B. B\u00e9zard, W. R. Pryor and H. Waite for valuable comments. This research was supported by NASA grant\nNAG-5-6263 and the Cassini Project.\n\nPublished - grl16654.pdf
", "abstract": "Jupiter has a large magnetosphere that episodically precipitates large amounts of energy into the polar atmosphere, giving rise to intense auroras [Clarke et al., 1996; Grodent et al., 2000]. An important consequence of this energy influx is the production of a dark haze [Pryor and Hord, 1991], the formation mechanism of which was hitherto poorly known. Recent observations of benzene on Jupiter [B\u00e9zard et al., 2001; Flasar, 2002] provide new clues for a chemical and aerosol model for the formation of heavy hydrocarbon aerosols. The chemistry begins with the destruction of methane by energetic particles, followed by neutral and ion reactions, ultimately leading to the formation of benzene and other complex hydrocarbons, including multi-ring compounds which subsequently condense. High temperatures and effective eddy mixing engendered by the auroras enhance the formation of heavy hydrocarbons and aerosols. This mechanism may be relevant in the atmospheres of Saturn and extrasolar giant planets, and is an example of how a planetary magnetosphere may influence the chemical composition and climate forcing of the upper atmosphere.", "date": "2003-04", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "30", "number": "8", "publisher": "American Geophysical Union", "pagerange": "Art. No. 1447", "id_number": "CaltechAUTHORS:20140820-093033046", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140820-093033046", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NAG-5-6263" }, { "agency": "NASA Cassini Project" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2002GL016661", "primary_object": { "basename": "grl16654.pdf", "url": "https://authors.library.caltech.edu/records/4e2gp-t4y17/files/grl16654.pdf" }, "resource_type": "article", "pub_year": "2003", "author_list": "Wong, Ah-San; Yung, Yuk L.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/fh69g-2wm68", "eprint_id": 48755, "eprint_status": "archive", "datestamp": "2023-08-23 23:47:30", "lastmod": "2023-10-17 20:24:32", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Gerstell-M-F", "name": { "family": "Gerstell", "given": "M. F." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Y. L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "A comment on tectonics and the future of terrestrial life", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 2002 Published by Elsevier Science B.V. Received 6 June 2002; accepted 5 September 2002; available online 7 December 2002.", "abstract": "Theory, and accumulating evidence, suggest that mantle convection and plate tectonics facilitated the rise of molecular oxygen in earth's atmosphere, through the burial of organic carbon (McCulloch, 1993, Des Marais, 1994 and Lindsay and Brasier, 2002).", "date": "2003-01-10", "date_type": "published", "publication": "Precambrian Research", "volume": "120", "number": "1-2", "publisher": "Elsevier", "pagerange": "177-178", "id_number": "CaltechAUTHORS:20140821-072714074", "issn": "0301-9268", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140821-072714074", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/S0301-9268(02)00143-2", "resource_type": "article", "pub_year": "2003", "author_list": "Gerstell, M. F. and Yung, Y. L." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/c0d88-8v173", "eprint_id": 48733, "eprint_status": "archive", "datestamp": "2023-08-23 23:47:24", "lastmod": "2023-10-17 20:23:19", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Summers-M-E", "name": { "family": "Summers", "given": "Michael E." } }, { "id": "Lieb-B-J", "name": { "family": "Lieb", "given": "B. Joseph" } }, { "id": "Chapman-E", "name": { "family": "Chapman", "given": "Emily" } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Atmospheric biomarkers of subsurface life on Mars", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2002 The American Geophysical Union.\n\nReceived 24 April 2002; Revised 19 June 2002; Accepted 18 July 2002; Published 20 December 2002.\n\nPublished - grl15999.pdf
", "abstract": "If life exists beneath the Martian surface similar to terrestrial bacteria that rely upon chemical reactions involving H_2 and/or CO as energy sources, then it may be possible to infer its existence by observing metabolic by-products that would appear as trace gases in the Martian atmosphere. We have studied the fate of organic trace gases in the Martian atmosphere and find that most have very short chemical lifetimes, however CH_4 has a chemical lifetime of about 300 yrs and thus it will tend to be uniformly distributed in the Martian atmosphere. Using the current observational upper limit on atmospheric CH_4 we deduce that its flux, from all sources, into the Martian atmosphere must be at least 10^5 times less than terrestrial value. If there are abiotic sources of CH_4 on Mars then the biological component of the CH4 must be even less.", "date": "2002-12-20", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "29", "number": "24", "publisher": "American Geophysical Union", "pagerange": "Art. No. 2171", "id_number": "CaltechAUTHORS:20140820-123329664", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140820-123329664", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2002GL015377", "primary_object": { "basename": "grl15999.pdf", "url": "https://authors.library.caltech.edu/records/c0d88-8v173/files/grl15999.pdf" }, "resource_type": "article", "pub_year": "2002", "author_list": "Summers, Michael E.; Lieb, B. Joseph; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/bprzt-yac13", "eprint_id": 4532, "eprint_status": "archive", "datestamp": "2023-08-23 23:25:17", "lastmod": "2023-10-16 17:48:41", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Irion-F-W", "name": { "family": "Irion", "given": "Fredrick W." } }, { "id": "Gunson-M-R", "name": { "family": "Gunson", "given": "Michael R." } }, { "id": "Toon-G-C", "name": { "family": "Toon", "given": "Geoff C." }, "orcid": "0000-0003-4174-7541" }, { "id": "Chang-Albert-Y", "name": { "family": "Chang", "given": "Albert Y." } }, { "id": "Eldering-A", "name": { "family": "Eldering", "given": "Annmarie" }, "orcid": "0000-0003-1080-9922" }, { "id": "Mahieu-E", "name": { "family": "Mahieu", "given": "Emmanuel" } }, { "id": "Manney-G-L", "name": { "family": "Manney", "given": "Gloria L." } }, { "id": "Michelsen-H-A", "name": { "family": "Michelsen", "given": "Hope A." } }, { "id": "Moyer-E-J", "name": { "family": "Moyer", "given": "Elizabeth J." } }, { "id": "Newchurch-M-J", "name": { "family": "Newchurch", "given": "Michael J." } }, { "id": "Osterman-G-B", "name": { "family": "Osterman", "given": "Gregory B." } }, { "id": "Rinsland-C-P", "name": { "family": "Rinsland", "given": "Curtis P." } }, { "id": "Salawitch-R-J", "name": { "family": "Salawitch", "given": "Ross J." } }, { "id": "Sen-B", "name": { "family": "Sen", "given": "Bhaswar" } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Zander-R", "name": { "family": "Zander", "given": "Rodolphe" } } ] }, "title": "Atmospheric Trace Molecule Spectroscopy (ATMOS) experiment version 3 data retrievals", "ispublished": "pub", "full_text_status": "public", "keywords": "Atmospheric composition; Remote sensing; Absorption spectroscopy", "note": "\u00a9 2002 Optical Society of America. \n\nReceived 4 December 2001; revised manuscript received 27 August 2002. \n\nThis effort builds on the work of past and present science and processing team members of the ATMOS experiment. We thank them and in particular C.B. Farmer, M.C. Abrams, and the late R.H. Norton. Research at the Jet Propulsion Laboratory, California Institute of Technology, was performed under contract to NASA.\n\nPublished - IRIao02.pdf
", "abstract": "Version 3 of the Atmospheric Trace Molecule Spectroscopy (ATMOS) experiment data set for some 30 trace and minor gas profiles is available. From the IR solar-absorption spectra measured during four Space Shuttle missions (in 1985, 1992, 1993, and 1994), profiles from more than 350 occultations were retrieved from the upper troposphere to the lower mesosphere. Previous results were unreliable for tropospheric retrievals, but with a new global-fitting algorithm profiles are reliably returned down to altitudes as low as 6.5 km (clouds permitting) and include notably improved retrievals of H2 O, CO, and other species. Results for stratospheric water are more consistent across the ATMOS spectral filters and do not indicate a net consumption of H2 in the upper stratosphere. A new sulfuric-acid aerosol product is described. An overview of ATMOS Version 3 processing is presented with a discussion of estimated uncertainties. Differences between these Version 3 and previously reported Version 2 ATMOS results are discussed. Retrievals are available at http: /atmos.jpl.nasa.gov /atmos.", "date": "2002-11-20", "date_type": "published", "publication": "Applied Optics", "volume": "41", "number": "33", "publisher": "Optical Society of America", "pagerange": "6968-6979", "id_number": "CaltechAUTHORS:IRIao02", "issn": "0003-6935", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:IRIao02", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "primary_object": { "basename": "IRIao02.pdf", "url": "https://authors.library.caltech.edu/records/bprzt-yac13/files/IRIao02.pdf" }, "resource_type": "article", "pub_year": "2002", "author_list": "Irion, Fredrick W.; Gunson, Michael R.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/6b5f0-1av92", "eprint_id": 52885, "eprint_status": "archive", "datestamp": "2023-08-22 01:28:54", "lastmod": "2023-10-18 21:44:26", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Mars: Atmospheric chemistry and astrobiology", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 2002 American Chemical Society.", "abstract": "It is nearly thirty years since the early pioneering work on the chemistry of the\nMartian atmosphere. Later work provided quantitative comparisons between\ntheory and observations. The status will be reviewed. Whether the composition\nof the Martian atmosphere can or cannot be accounted by photochemistry and\ngeochemistry becomes a question of great importance for Astrobiology. In 1965\nLovelock wrote a seminal paper on the detection of extraterrestrial life on the\nbasis of departure from thermodynamic equilibrium. Unfortunately, both\nphotochemistry and biochemistry are disequilibrium driving forces, and we must\nunderstand the system in sufficient detail to be able to distinguish the two.", "date": "2002-08-18", "date_type": "published", "publication": "Abstracts of Papers of the American Chemical Society", "volume": "224", "publisher": "American Chemical Society", "pagerange": "PHYS-028", "id_number": "CaltechAUTHORS:20141216-134018031", "issn": "0065-7727", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20141216-134018031", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "resource_type": "article", "pub_year": "2002", "author_list": "Yung, Yuk L." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/g92kh-tn982", "eprint_id": 47445, "eprint_status": "archive", "datestamp": "2023-08-22 01:27:46", "lastmod": "2023-10-26 20:36:20", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Kuang-Zhiming", "name": { "family": "Kuang", "given": "Zhiming" } }, { "id": "Margolis-J-S", "name": { "family": "Margolis", "given": "Jack" } }, { "id": "Toon-G-C", "name": { "family": "Toon", "given": "Geoffrey" }, "orcid": "0000-0003-4174-7541" }, { "id": "Crisp-D", "name": { "family": "Crisp", "given": "David" }, "orcid": "0000-0002-4573-9998" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk" }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Spaceborne measurements of atmospheric CO_2 by high-resolution NIR spectrometry of reflected sunlight: An introductory study", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2002 The American Geophysical Union.\n\nReceived 30 October 2001; Revised 12 February 2002; Accepted 12 February 2002; Published 2 August 2002.\n\nWe thank two anonymous referees and members of the OCO Team for valuable comments. This research was supported in part by a NASA grant to the Jet Propulsion Laboratory and the Caltech President's Fund. ZMK and YLY were supported by NASA grants NAG5-7230, NAG1-1806 to Caltech.\n\nPublished - grl15484.pdf
", "abstract": "We introduce a strategy for measuring the column-averaged\nCO_2 dry air volume mixing ratio X_(CO_2) from space. It employs high resolution spectra of reflected sunlight taken simultaneously in near-infrared (NIR) CO_2 (1.58-mm and 2.06-mm) and O_2 (0.76-mm) bands. Simulation experiments, show that precisions of ~0.3\u20132.5 ppmv for X_(CO_2) can be achieved from individual clear sky soundings for a range of atmospheric/surface conditions when the scattering optical depth t_s is less than ~0.3. When averaged over many clear sky soundings, random errors become negligible. This high precision facilitates the identification and correction of systematic errors, which are recognized as the most serious impediment for the satellite X_(CO_2) measurements. We briefly discuss potential sources of systematic\nerrors, and show that some of them may result in geographically varying biases in the measured X_(CO_2). This highlights the importance of careful calibration and validation measurements, designed to identify and eliminate sources of these biases. We conclude that the 3-band, spectrometric approach using NIR reflected sunlight has the potential for highly accurate X_(CO_2) measurements.", "date": "2002-08-01", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "29", "number": "15", "publisher": "American Geophysical Union", "pagerange": "Art. No. 1716", "id_number": "CaltechAUTHORS:20140723-155213874", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140723-155213874", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Caltech President's Fund" }, { "agency": "NASA", "grant_number": "NAG5-7230" }, { "agency": "NASA", "grant_number": "NAG1-1806" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2001GL014298", "primary_object": { "basename": "grl15484.pdf", "url": "https://authors.library.caltech.edu/records/g92kh-tn982/files/grl15484.pdf" }, "resource_type": "article", "pub_year": "2002", "author_list": "Kuang, Zhiming; Margolis, Jack; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/kg96s-qd992", "eprint_id": 48752, "eprint_status": "archive", "datestamp": "2023-08-22 01:27:32", "lastmod": "2023-10-17 20:24:17", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Friedson-A-J", "name": { "family": "Friedson", "given": "A. James" } }, { "id": "Wong-A-S", "name": { "family": "Wong", "given": "Ah-San" } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Models for Polar Haze Formation in Jupiter's Stratosphere", "ispublished": "pub", "full_text_status": "restricted", "keywords": "Jupiter; atmosphere; photochemistry; aurorae", "note": "\u00a9 2002 Elsevier Science.\n\nReceived October 9, 2001; Revised April 1, 2002.\n\nWe thank R. A.West, K. Rages, M. Lemmon, and S. G. Edgington for helpful discussions. We also thank R. G. Gladstone and an anonymous reviewer for their insightful reviews. Many of the calculations were performed on the Cray\nSV1 supercomputer managed by the Jet Propulsion Laboratory Supercomputing Project. This work was supported by a grant from the NASA Planetary Atmospheres Program. The work was performed by the Jet Propulsion Laboratory, California Institute of Technology, under contract with the National Aeronautics and Space Administration.", "abstract": "We present coupled chemical\u2013microphysical models for the formation, growth, and physical properties of the jovian polar haze based on a gas-phase photochemical model for the auroral regions developed by A. S. Wong et al. (2000, Astrophys. J.534, L215\u2013217). In this model, auroral particle precipitation provides an important energy source for enhanced decomposition of methane and production of benzene and polycyclic aromatic hydrocarbons (PAHs). We find that at high altitude, A_4 (pyrene, a hydrocarbon consisting of four fused aromatic rings) should homogeneously nucleate to form tiny primary particles. At lower altitudes, A_3 (phenanthrene) and A_2 (naphthalene) heterogeneously nucleate on the A4 nuclei. These particles subsequently grow by additional condensation of A_2 on the nucleated particles and by coagulation and eventually sediment out to the troposphere. We run different cases of the aerosol microphysical model for different assumptions regarding the fractal dimension of aggregate particles formed by the coagulation process. If coagulation is assumed to produce spherical particles (of dimensionality 3), then their mean radius at altitudes below the 20-mbar pressure level is computed to be approximately 0.1 \u03bcm. If coagulation produces fractal aggregates of dimension 2.1, then their equivalent mean radius below the 20-mbar level is much larger, of order 0.7 \u03bcm. Aggregates with fractal dimensions between 2.1 and 3 form with equivalent mean radii between 0.1 and 0.7 \u03bcm. In every case, mean particle radius is found to decrease with increasing altitude, as expected for a system approximately in sedimentation\u2013coagulation equilibrium. The predicted range of altitudes where aerosol formation occurs and the mean size to which particles grow are found to be generally consistent with observations. However, our calculations cannot presently account for the large amount of total aerosol loading inferred by M. G. Tomasko et al. (1986, Icarus65, 218\u2013243). We suggest that the primarily neutral chemical pathway to heavy hydrocarbon and PAH formation proposed by Wong et al. (2000) may proceed too slowly to produce a sufficient amount of condensible material. Inclusion of ion and ion\u2013neutral reactions in the chemical scheme could potentially lead to the prediction of higher PAH production rates, higher nucleation rates, and greater aerosol loading, producing better agreement with the observations.", "date": "2002-08", "date_type": "published", "publication": "Icarus", "volume": "158", "number": "2", "publisher": "Elsevier", "pagerange": "389-400", "id_number": "CaltechAUTHORS:20140820-161912639", "issn": "0019-1035", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140820-161912639", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA Planetary Atmospheres Program" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1006/icar.2002.6885", "resource_type": "article", "pub_year": "2002", "author_list": "Friedson, A. James; Wong, Ah-San; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/f9w0k-pne27", "eprint_id": 48746, "eprint_status": "archive", "datestamp": "2023-08-22 01:22:43", "lastmod": "2023-10-17 20:23:56", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Huang-X", "name": { "family": "Huang", "given": "Xianglei" } }, { "id": "Farrara-J", "name": { "family": "Farrara", "given": "John" } }, { "id": "Leroy-S-S", "name": { "family": "Leroy", "given": "Stephen S." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Goody-R-M", "name": { "family": "Goody", "given": "Richard M." } } ] }, "title": "Cloud variability as revealed in outgoing infrared spectra: Comparing model to observation with spectral EOF analysis", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2002 The American Geophysical Union.\n\nReceived 3 October 2001; Revised 8 January 2002; Accepted 16 January 2002; Published 30 April 2002.\n\nWe thank A. Ingersoll, M. Gerstell, G. Toon and R. Zurek for valuable comments. We wish to thank two anonymous\nreferees for improving the paper. This research is supported by NOAA grant Grant No. NA06EC0505 to the California Institute of Technology.\n\nPublished - grl15411.pdf
", "abstract": "Spectrally resolved outgoing radiance is a potentially powerful tool for testing climate models. To show how it can be used to evaluate the simulation of cloud variability, which is the principal uncertainty in current climate models, we apply spectral empirical orthogonal function (EOF) analysis to satellite radiance spectra and synthetic spectra derived from a general circulation model (GCM). We show that proper averaging over a correct timescale is necessary before applying spectral EOF analysis. This study focuses on the Central Pacific and the western Pacific Warm Pool. For both observation and GCM output, cloud variability is the dominant contributor to the first principal component that accounts for more than 95% of the total variance. However, the amplitude of the first principal component derived from the observations (2 \u223c 3.4 W m^(\u22122)) is 2 \u223c 6 times greater than that of the GCM simulation. This suggests that cloud variability in the GCM is significantly smaller than that in the real atmosphere.", "date": "2002-04-15", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "29", "number": "8", "publisher": "American Geophysical Union", "pagerange": "Art. No. 1270", "id_number": "CaltechAUTHORS:20140820-151655637", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140820-151655637", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "National Oceanic and Atmospheric Administration (NOAA)", "grant_number": "NA06EC0505" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2001GL014176", "primary_object": { "basename": "grl15411.pdf", "url": "https://authors.library.caltech.edu/records/f9w0k-pne27/files/grl15411.pdf" }, "resource_type": "article", "pub_year": "2002", "author_list": "Huang, Xianglei; Farrara, John; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/c4m3f-jw705", "eprint_id": 48756, "eprint_status": "archive", "datestamp": "2023-08-22 01:21:06", "lastmod": "2023-10-17 20:24:34", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Wong-A-S", "name": { "family": "Wong", "given": "Ah-San" } }, { "id": "Morgan-C-G", "name": { "family": "Morgan", "given": "Christopher G." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Owen-T", "name": { "family": "Owen", "given": "Tobias" } } ] }, "title": "Evolution of CO on Titan", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 2002 Elsevier Science (USA). Received May 11, 2001; revised July 12, 2001. Available online 12 April 2002. We thank F. S. Rowland for an illuminating discussion of the ^1CH_2 and CO reaction and W. B. DeMore and K. Bayes for valuable advice on the kinetics of hydrocarbons and CO.We thank Nicolas Biver for carrying out the observations of Titan with the JCMT and J. I. Moses for providing the code on which the Titan model is based. M. Allen provided critical inputs to a preliminary version of the paper, resulting in the present paper. We thank M. A. Gurwell and M. F. Gerstell for comments and suggestions. This research was supported in part by NAG5-6263 and the Cassini Project. C.G.M. thanks the National Research Council for an NRC Postdoctoral Fellowship.", "abstract": "The early evolution of Titan's atmosphere is expected to produce enrichment in the heavy isotopomers of CO, ^(13)CO and C^(18)O, relative to ^(12)C^(16)O. However, the original isotopic signatures may be altered by photochemical reactions. This paper explains why there is no isotopic enrichment in C in Titan's atmosphere, despite significant enrichment of heavy H, N, and O isotopes. We show that there is a rapid exchange of C atoms between the CH_4 and CO reservoirs, mediated by the reaction ^1CH_2+^*CO\u2192^(1*)CH_2+CO, where ^*C is ^(13)C. Based on recent laboratory measurements, we estimate the rate coefficient for this reaction to be 3.2\u00d710^(\u221212) cm^3 s^(\u22121) at the temperature appropriate for the upper atmosphere of Titan. We investigate the isotopic dilution of CO using the Caltech/JPL one-dimensional photochemical model of Titan. Our model suggests that the time constant for isotopic exchange through the above reaction is about 800 Myr, which is significantly shorter than the age of Titan, and therefore any original isotopic enhancement of ^(13)C in CO may have been diluted by the exchange process. In addition, a plausible model for the evolution history of CO on Titan after the initial escape is proposed.", "date": "2002-02", "date_type": "published", "publication": "Icarus", "volume": "155", "number": "2", "publisher": "Elsevier", "pagerange": "382-392", "id_number": "CaltechAUTHORS:20140821-075531138", "issn": "0019-1035", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140821-075531138", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NAG5-6263" }, { "agency": "Cassini Project" }, { "agency": "National Research Council (NRC) Postdoctoral Fellowship" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1006/icar.2001.6720", "resource_type": "article", "pub_year": "2002", "author_list": "Wong, Ah-San; Morgan, Christopher G.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/6m4ay-99j23", "eprint_id": 48737, "eprint_status": "archive", "datestamp": "2023-08-22 01:16:36", "lastmod": "2023-10-17 20:23:27", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Bahou-M", "name": { "family": "Bahou", "given": "Mohammed" } }, { "id": "Chung-C-Y", "name": { "family": "Chung", "given": "Chao-Yu" } }, { "id": "Lee-Y-P", "name": { "family": "Lee", "given": "Yuan-Pern" } }, { "id": "Cheng-B-M", "name": { "family": "Cheng", "given": "Bing-Ming" } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Lee-L-C", "name": { "family": "Lee", "given": "L. C." } } ] }, "title": "Absorption cross sections of HCl and DCl at 135-232 nanometers: implications for photodissociation on Venus", "ispublished": "pub", "full_text_status": "public", "keywords": "planets and satellites: individual (Venus); ultraviolet: solar system", "note": "\u00a9 2001 American Astronomical Society.\n\nReceived 2001 July 6; accepted 2001 August 13; published 2001 September 7.\n\nWe thank M. Gerstell for useful comments. L. C. Lee thanks the Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei, Taiwan, for a visiting professorship. Y. L. Y. acknowledges support by NASA grant NAG5-6263.\n\nPublished - 1538-4357_559_2_L179.pdf
", "abstract": "Cross sections for photoabsorption of HCl and DCl are determined in the spectral region of 135-232 nm using radiation from a synchrotron light source. At wavelengths near the onset of absorption (\u03bb > 200 nm), cross sections of HCl are approximately 5-10 times larger than those of DCl. These data are used to calculate rates of photodissociation of HCl and DCl in the Venusian atmosphere. For the entire wavelength region measured, the rate of photodissociation of DCl is only 16% that of HCl. The difference in rates of photodissociation contributes to the exceptionally large [D]/[H] ratio of the Venusian atmosphere.", "date": "2001-10-01", "date_type": "published", "publication": "Astrophysical Journal Letters", "volume": "559", "number": "2", "publisher": "American Astronomical Society", "pagerange": "L179-L182", "id_number": "CaltechAUTHORS:20140820-133529847", "issn": "2041-8205", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140820-133529847", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NAG5-6263" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1086/323753", "primary_object": { "basename": "1538-4357_559_2_L179.pdf", "url": "https://authors.library.caltech.edu/records/6m4ay-99j23/files/1538-4357_559_2_L179.pdf" }, "resource_type": "article", "pub_year": "2001", "author_list": "Bahou, Mohammed; Chung, Chao-Yu; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/rcq80-n8v04", "eprint_id": 48738, "eprint_status": "archive", "datestamp": "2023-08-22 01:12:53", "lastmod": "2023-10-17 20:23:30", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Lee-Anthony-Y-T", "name": { "family": "Lee", "given": "Anthony Y. T." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Cheng-Bing-Ming", "name": { "family": "Cheng", "given": "Bing-Ming" } }, { "id": "Bahou-Mohammed", "name": { "family": "Bahou", "given": "Mohammed" } }, { "id": "Chung-Chao-Yu", "name": { "family": "Chung", "given": "Chao-Yu" } }, { "id": "Lee-Yuan-Pern", "name": { "family": "Lee", "given": "Yuan-Pern" } } ] }, "title": "Enhancement of deuterated ethane on Jupiter", "ispublished": "pub", "full_text_status": "public", "keywords": "planets and satellites: individual (Jupiter)", "note": "\u00a9 2001 American Astronomical Society.\n\nReceived 2000 October 3; accepted 2001 January 26; published 2001 April 3.\n\nWe thank M. Allen, M. F. Gerstell, and C. Parkinson for\nhelpful comments. This work was supported by NASA grant\nNAG5-6263 and the Cassini UVSI project.\n\nPublished - 1538-4357_551_1_L93.pdf
", "abstract": "We report laboratory measurements of cross sections of CH_3D and C_2H_5D in the extreme ultraviolet. The results are incorporated in a photochemical model for the deuterated hydrocarbons up to C_2 in the upper atmosphere of Jupiter, taking into account the fast reactions for exchanging H and D atoms between H_2 and CH_4, H + HD \u2194 D + H_2, CH_3 + D \u2194 CH_2D + H. Since there is no reliable kinetics measurement for the reaction, CH_2D + H \u2192 CH_3 + D, we use Yung et al.'s estimate for its rate constant. The strong temperature dependence for this reaction leads to large isotopic fractionation for CH_3D and C_2H_5D in the upper atmosphere of Jupiter, where their production rates depend on the abundance of deuterated methyl radical. The model predicts that the D/H ratio in deuterated ethane is about 15 times that of the bulk atmosphere. A confirmation of this result would provide a sensitive test of the photochemistry of hydrocarbons in the atmosphere of Jupiter.", "date": "2001-04-10", "date_type": "published", "publication": "Astrophysical Journal Letters", "volume": "551", "number": "1", "publisher": "American Astronomical Society", "pagerange": "L93-L96", "id_number": "CaltechAUTHORS:20140820-133651921", "issn": "2041-8205", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140820-133651921", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NAG5-6263" }, { "agency": "Cassini UVSI Project" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1086/319827", "primary_object": { "basename": "1538-4357_551_1_L93.pdf", "url": "https://authors.library.caltech.edu/records/rcq80-n8v04/files/1538-4357_551_1_L93.pdf" }, "resource_type": "article", "pub_year": "2001", "author_list": "Lee, Anthony Y. T.; Yung, Yuk L.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/wpc8z-yqr96", "eprint_id": 48938, "eprint_status": "archive", "datestamp": "2023-08-22 01:12:47", "lastmod": "2023-10-17 20:33:31", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Camp-C-D", "name": { "family": "Camp", "given": "Charles D." } }, { "id": "Roulston-M-S", "name": { "family": "Roulston", "given": "Mark S." } }, { "id": "Haldemann-A-F-C", "name": { "family": "Haldemann", "given": "Albert F. C." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "The sensitivity of tropospheric methane to the interannual variability in stratospheric ozone", "ispublished": "pub", "full_text_status": "restricted", "keywords": "Interannual oscillation; QBO; Atmosphere; Stratosphere\u2013troposphere interaction; Insolation", "note": "\u00a9 2001 Elsevier Science Ltd. Received 25 April 2000. Revised 8 August 2000. Accepted 12 September 2000. Available online 15 March 2001. We thank M. Gerstell, P. Wennberg, J. Randerson, A. Ruzmaikin, A. Gould, J. Wang, R. Salawitch and an anonymous reviewer for helpful comments, E.J. Dlugokencky of NOAA-CMDL for the use of CH_4 data from the NOAA-CMDL global flask sampling network, and Rich Stolarski of NASA Goddard Space Flight Center for the use of O_3 data from the merged ozone data set. Supported by NASA grants NAG5-7230 and NAG1-1806 to the California Institute of Technology.", "abstract": "The dominant processes affecting the concentration of tropospheric methane on interannual timescales are the biospheric and anthropogenic sources and changes in the abundance of the hydroxyl radical caused by the changes in the UV flux which result from changes in stratospheric ozone abundance. We have carried out an empirical study of the sensitivity of the methane to fluctuations in ozone column abundance. This analysis was carried out using monthly mean surface methane concentrations measured by the National Oceanic and Atmospheric Administration \u2013 Climate Monitoring and Diagnostics Laboratory (NOAA-CMDL) Global Cooperative Air Sampling Network from 1983 to 1998 and ozone column abundances obtained by the Total Ozone Mapping Spectrometer (TOMS) and the EP TOMS instruments over the same time period. We focused on interannual variability with periods between 15 and 60 months, in which interval the dominant ozone fluctuation is the quasi-biennial oscillation (QBO), with a period of approximately 29 months. In order to isolate the response of methane to ozone from the effects of variability in the sources and transport of methane, we restricted our analysis to data at mid-latitudes in the southern hemisphere. A statistical study shows that the sensitivity factor \u03b1\u2261\u2212d(ln[CH_4])/d(ln[O_3])=\u22120.038\u00b10.009. The response of CH_4 lags approximately 6 months behind the forcing by O_3. A simple model was used to interpret the empirical results. Our results confirm that any mechanism that affects stratospheric ozone impacts the oxidizing potential of the troposphere. CH_4 fluctuations provide a quantitative measure of this important effect linking the upper and the lower atmosphere.", "date": "2001-04", "date_type": "published", "publication": "Chemosphere: Global Change Science", "volume": "3", "number": "2", "publisher": "Elsevier", "pagerange": "147-156", "id_number": "CaltechAUTHORS:20140826-141758051", "issn": "0045-6535", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140826-141758051", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NAG5-7230" }, { "agency": "NASA", "grant_number": "NAG1-1806" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/S1465-9972(00)00053-2", "resource_type": "article", "pub_year": "2001", "author_list": "Camp, Charles D.; Roulston, Mark S.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/r14t5-3t836", "eprint_id": 9133, "eprint_status": "archive", "datestamp": "2023-08-21 22:01:47", "lastmod": "2023-10-16 21:55:53", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Gerstell-M-F", "name": { "family": "Gerstell", "given": "M. F." } }, { "id": "Francisco-J-S", "name": { "family": "Francisco", "given": "J. S." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Y. L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Boxe-C-S", "name": { "family": "Boxe", "given": "C." } }, { "id": "Aaltonee-E-T", "name": { "family": "Aaltonee", "given": "E. T." } } ] }, "title": "Keeping Mars warm with new super greenhouse gases", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2001 by the National Academy of Sciences. \n\nEdited by Donald M. Hunten, University of Arizona, Tucson, AZ, and approved January 11, 2001 (received for review October 26, 2000). This paper was submitted directly (Track II) to the PNAS office. \n\nWe thank J. Blamont, A. Haldemann, and K. Nealson for stimulating discussions on climate modifications by using greenhouse gases and G. Blake for a conversation on bandwidths. We thank M. Marinova for a thoughtful reading and for pointing out a reference we had neglected. We thank the National Academy of Science's Member Editor and two anonymous referees for their comments. This research is supported in part by the National Aeronautics and Space Administration Grant NAG5-4022 and National Science Foundation Grant AST-9816409.\n\nPublished - GERpnas01.pdf
", "abstract": "Our selection of new super greenhouse gases to fill a putative \"window\" in a future Martian atmosphere relies on quantum-mechanical calculations. Our study indicates that if Mars could somehow acquire an Earth-like atmospheric composition and surface pressure, then an Earth-like temperature could be sustained by a mixture of five to seven fluorine compounds. Martian mining requirements for replenishing the fluorine could be comparable to current terrestrial extraction.", "date": "2001-02-27", "date_type": "published", "publication": "Proceedings of the National Academy of Sciences of the United States of America", "volume": "98", "number": "5", "publisher": "National Academy of Sciences", "pagerange": "2154-2157", "id_number": "CaltechAUTHORS:GERpnas01", "issn": "0027-8424", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:GERpnas01", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NAG5-4022" }, { "agency": "NSF", "grant_number": "AST-9816409" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1073/pnas.051511598", "pmcid": "PMC30108", "primary_object": { "basename": "GERpnas01.pdf", "url": "https://authors.library.caltech.edu/records/r14t5-3t836/files/GERpnas01.pdf" }, "resource_type": "article", "pub_year": "2001", "author_list": "Gerstell, M. F.; Francisco, J. S.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/803ym-1t202", "eprint_id": 48749, "eprint_status": "archive", "datestamp": "2023-08-22 01:06:42", "lastmod": "2023-10-17 20:24:08", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Miller-C-E", "name": { "family": "Miller", "given": "Charles E." }, "orcid": "0000-0002-9380-4838" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Photo-induced isotopic fractionation", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2000 by the American Geophysical Union. \n\nReceived April 17, 2000: revised June 13, 2000. Paper number 2000JD900388. The authors would like to thank Y. P. Lee for the H2O, HDO, and D2O absorption cross section data, R. van Harrevelt and M. van Hemert for sharing their ab initio absorption cross sections prior to publication, and D. Schwenke for the water\nisotopomer zero point energies.\n\nPublished - jgrd7729.pdf
", "abstract": "This paper presents a systematic method for the analysis of photo-induced isotopic fractionation. The physical basis for this fractionation mechanism centers on the fact that isotopic substitution alters the energy levels, molecular symmetries, spin statistical weights and other fundamental molecular properties, producing spectroscopic signatures distinguishable from that of the parent isotopomer. These mass-dependent physical properties are identical to those invoked by Urey to explain stable isotope fractionation in chemical systems subject to thermodynamic equilibrium. Photo-induced isotopic fractionation is a completely general phenomenon and should be observable in virtually all gas phase photochemical systems. Water photo-induced isotopic fractionation has been examined in detail using experimental and theoretical data. These results illustrate the salient features of this fractionation mechanism for molecules possessing continuous UV absorption spectra and unit photodissociation quantum yields. Using the photo-induced isotopic fractionation methodology in conjunction with standard photochemical models, we predict substantial deuterium enrichment of water vapor in the planetary atmospheres of Earth and Mars.", "date": "2000-12-16", "date_type": "published", "publication": "Journal of Geophysical Research D", "volume": "105", "number": "D23", "publisher": "American Geophysical Union", "pagerange": "29039-29051", "id_number": "CaltechAUTHORS:20140820-153601637", "issn": "0148-0227", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140820-153601637", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2000JD900388", "primary_object": { "basename": "jgrd7729.pdf", "url": "https://authors.library.caltech.edu/records/803ym-1t202/files/jgrd7729.pdf" }, "resource_type": "article", "pub_year": "2000", "author_list": "Miller, Charles E. and Yung, Yuk L." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/6ckzs-3jw44", "eprint_id": 48743, "eprint_status": "archive", "datestamp": "2023-08-22 01:03:32", "lastmod": "2023-10-17 20:23:44", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Lee-Anthony-Y-T", "name": { "family": "Lee", "given": "Anthony Y. T." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Moses-J-I", "name": { "family": "Moses", "given": "Julianne" }, "orcid": "0000-0002-8837-0035" } ] }, "title": "Photochemical modeling of CH_3 abundances in the outer solar system", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2000 by the American Geophysical Union. \n\nReceived September 20, 1999; revised April 6, 2000; accepted April 11, 2000. We thank W. DeMore and K. Bayes for valuable theoretical chemical rate constant estimates. We also thank M. Allen, M. Gerstell, and two anonymous referees for helpful comments. This research is supported by NASA grant NAG5-6263 to the California Institute of Technology.\n\nPublished - jgre1169.pdf
", "abstract": "Recent measurements of methyl radicals (CH_3) in the upper atmospheres of Saturn and Neptune by the Infrared Space Observatory (ISO) provide new constraints to photochemical models of hydrocarbon chemistry in the outer solar system. The derived column abundances of CH_3 on Saturn above 10 mbar and Neptune above the 0.2 mbar pressure level are (2.5\u20136.0) \u00d7 10^(13) cm^(\u22122) and (0.7\u20132.8) \u00d7 10^(13) cm^(\u22122), respectively. We use the updated Caltech/Jet Propulsion Laboratory photochemical model, which incorporates hydrocarbon photochemistry, vertical molecular and bulk atmospheric eddy diffusion, and realistic radiative transfer modeling, to study the CH_3 abundances in the upper atmosphere of the giant planets and Titan. We identify the key reactions that control the concentrations of CH_3 in the model, such as the three-body recombination reaction, CH_3 + CH_3 + M \u2192 C_2H_6 + M. We evaluate and extrapolate the three-body rate constant of this reaction to the low-temperature limit (1.8\u00d710^(\u221216) T^(\u22123.75) e^(\u2212300/T), T<300 K) and compare methyl radical abundances in five atmospheres: Jupiter, Saturn, Uranus, Neptune, and Titan. The sensitivity of our models to the rate coefficients for the reactions H + CH_3 + M \u2192 CH_4 + M, H + C_2H_3 \u2192 C_2H_2 + H_2, ^1CH_2 + H_2 \u2192 CH_3 + H, and H + C_2H_5 \u2192 2 CH_3, the branching ratios of CH_4 photolysis, vertical mixing in the five atmospheres, and Lyman \u03b1 photon enhancement at the orbit of Neptune have all been tested. The results of our model CH_3 abundances for both Saturn (5.1\u00d710^(13) cm^(\u22122)) and Neptune (2.2\u00d710^(13) cm^(\u22122)) show good agreement with ISO Short Wavelength Spectrometer measurements. Using the same chemical reaction set, our calculations also successfully generate vertical profiles of stable hydrocarbons consistent with Voyager and ground-based measurements in these outer solar system atmospheres. Predictions of CH_3 column concentrations (for p\u22640.2 mbar) in the atmospheres of Jupiter (3.3\u00d710^(13) cm^(\u22122)), Uranus (2.5\u00d710^(12) cm^(\u22122)), and Titan (1.9\u00d710^(15) cm^(\u22122)) may be checked by future observations.", "date": "2000-08-25", "date_type": "published", "publication": "Journal of Geophysical Research E", "volume": "105", "number": "E8", "publisher": "American Geophysical Union", "pagerange": "20207-20225", "id_number": "CaltechAUTHORS:20140820-144239502", "issn": "0148-0227", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140820-144239502", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NAG5-6263" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/1999JE001186", "primary_object": { "basename": "jgre1169.pdf", "url": "https://authors.library.caltech.edu/records/6ckzs-3jw44/files/jgre1169.pdf" }, "resource_type": "article", "pub_year": "2000", "author_list": "Lee, Anthony Y. T.; Yung, Yuk L.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/gt89f-fbg64", "eprint_id": 48734, "eprint_status": "archive", "datestamp": "2023-08-22 01:03:17", "lastmod": "2023-10-17 20:23:22", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Kuang-Z", "name": { "family": "Kuang", "given": "Zhiming" } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Reflectivity variations off the Peru Coast: Evidence for indirect effect of anthropogenic sulfate aerosols on clouds", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2000 The American Geophysical Union.\n\nReceived November 22, 1999; Revised June 12, 2000; Accepted June 12, 2000.\n\nPaper number 2000GL011376.\n\nThis research was supported by NASA grants NAG5-7230 and NAG5-7680. We thank Y. Jiang, X. Huang, H. Yu for useful discussions, X. Huang for help with the NCEP/NCAR data, S. Byrne, M. Getstell, R. Kahn, J. Kiehl, J. Seinfeld, H. Wang for valuable comments. We thank two anonymous referees for improving the paper.\n\nPublished - grl13629.pdf
", "abstract": "Using reflectivity measurements from the Total Ozone Mapping Spectrometer (TOMS), we show that over the months when stratocumulus clouds are prominent off the Peru Coast, the ultraviolet (UV) reflectance of two marine sites is consistently higher than that of the surroundings. The regions of reflectivity enhancement coincide with large anthropogenic sulfate aerosol emission sources, and the magnitude of the enhancement has a strong seasonal dependence that is related to the seasonal cloud movement. We propose the indirect aerosol effect as a plausible explanation for the reflectivity observations.", "date": "2000-08-15", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "27", "number": "16", "publisher": "American Geophysical Union", "pagerange": "2501-2504", "id_number": "CaltechAUTHORS:20140820-130043334", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140820-130043334", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NAG5-7230" }, { "agency": "NASA", "grant_number": "NAG5-7680" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2000GL011376", "primary_object": { "basename": "grl13629.pdf", "url": "https://authors.library.caltech.edu/records/gt89f-fbg64/files/grl13629.pdf" }, "resource_type": "article", "pub_year": "2000", "author_list": "Kuang, Zhiming and Yung, Yuk L." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/vzbj6-wry77", "eprint_id": 48936, "eprint_status": "archive", "datestamp": "2023-08-22 01:02:36", "lastmod": "2023-10-17 20:33:22", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Miller-C-E", "name": { "family": "Miller", "given": "Charles E." }, "orcid": "0000-0002-9380-4838" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Photo-induced isotopic fractionation of stratospheric N_2O", "ispublished": "pub", "full_text_status": "restricted", "keywords": "N2O; Isotopic fractionation; Photodissociation; Multi-isotope correlations", "note": "\u00a9 2000 Elsevier Science Ltd. Received 15 June 1999; accepted 28 October 1999. Available online 8 January 2001. The authors wish to thank M. Thiemens, T. Rahn and G.A. Blake for interesting discussions as well as N. Yoshida, T. R\u00f6ckmann, H. Zhang, and H. Umemoto for sharing their data prior to publication. CEM thanks the N_2O Conference organizers for the invitation to present the PHIFE paper in Tsukuba. YLY was supported in part by NSF ATM-9903790.", "abstract": "This paper shows that N_2O isotopic fractionation in the stratosphere may be understood within the limits of the standard photochemical models if mass-dependent photodissociation rates for the various N_2O isotopomers are incorporated. Thus, we conclude that there is no demonstrable reason to invoke a significant chemical source of N_2O in the middle atmosphere. This paper presents a general theory for isotopomer dependent photodissociation rates that accounts for the isotopic fractionation observed in stratospheric N_2O and how photodissociations appear to be both a source and a sink of N_2O in the middle atmosphere. Photo-induced isotopic fractionation effects (PHIFE), explain the distinct fractionation signatures found for ^(15)N/^(14)N and ^(18)O/^(16)O ratios in both laboratory and remote sensing measurements. Furthermore, PHIFE predicts substantially different isotopic fractionations in the stratosphere for the isotopomers ^(15)N^(14)N^(16)O and ^(14)N^(15)N^(16)O, which have identical molecular weights but different isotopic substitution sites. Modeling results based on this theory suggest that there is no demonstrable reason to invoke a significant chemical source of N_2O in the middle atmosphere and that N_2O multi-isotope correlations should prove a useful measure of stratospheric air parcel history.", "date": "2000-07-01", "date_type": "published", "publication": "Chemosphere: Global Change Science", "volume": "2", "number": "3-4", "publisher": "Elsevier", "pagerange": "255-266", "id_number": "CaltechAUTHORS:20140826-140311446", "issn": "0045-6535", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140826-140311446", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "ATM-9903790" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/S1465-9972(00)00011-8", "resource_type": "article", "pub_year": "2000", "author_list": "Miller, Charles E. and Yung, Yuk L." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/ajt5g-8e719", "eprint_id": 48890, "eprint_status": "archive", "datestamp": "2023-08-22 01:00:10", "lastmod": "2023-10-17 20:31:01", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Wong-Ah-San", "name": { "family": "Wong", "given": "Ah-San" } }, { "id": "Lee-Anthony-Y-T", "name": { "family": "Lee", "given": "Anthony Y. T." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Ajello-J-M", "name": { "family": "Ajello", "given": "Joseph M." } } ] }, "title": "Jupiter: aerosol chemistry in the polar atmosphere", "ispublished": "pub", "full_text_status": "public", "keywords": "planets and satellites: individual (Jupiter)", "note": "\u00a9 2000 The American Astronomical Society.\n\nReceived 2000 February 23; accepted 2000 March 31; published 2000 May 4.\n\nWe thank R. A.West for discussion on the aerosol formation,\nB. B\u00e9zard for result on ISO observations, and M. Allen, M. F.\nGerstell, and G. D. McDonald for helpful comments. This work\nwas supported by NASA grants NAG5-6263 and NAG5-8257\nand two grants to J. M. A. at JPL.\n\nPublished - 1538-4357_534_2_L215.pdf
", "abstract": "Aromatic compounds have been considered a likely candidate for enhanced aerosol formation in the polar region of Jupiter. We develop a new chemical model for aromatic compounds in the Jovian auroral thermosphere/ionosphere. The model is based on a previous model for hydrocarbon chemistry in the Jovian atmosphere and is constrained by observations from Voyager, Galileo, and the Infrared Space Observatory. Precipitation of energetic electrons provides the major energy source for the production of benzene and other heavier aromatic hydrocarbons. The maximum mixing ratio of benzene in the polar model is 2 \u00d7 10^(-9), a value that can be compared with the observed value (2^(+2)_(-1)) \u00d7 10^(-9) in the north polar auroral region. Sufficient quantities of the higher ring species are produced so that their saturated vapor pressures are exceeded. Condensation of these molecules is expected to lead to aerosol formation.", "date": "2000-05-10", "date_type": "published", "publication": "Astrophysical Journal Letters", "volume": "534", "number": "2", "publisher": "American Astronomical Society", "pagerange": "L215-L217", "id_number": "CaltechAUTHORS:20140826-084858839", "issn": "2041-8205", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140826-084858839", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NAG5-6263" }, { "agency": "NASA", "grant_number": "NAG5-8257" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1086/312675", "primary_object": { "basename": "1538-4357_534_2_L215.pdf", "url": "https://authors.library.caltech.edu/records/ajt5g-8e719/files/1538-4357_534_2_L215.pdf" }, "resource_type": "article", "pub_year": "2000", "author_list": "Wong, Ah-San; Lee, Anthony Y. T.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/r3wgb-raw15", "eprint_id": 48771, "eprint_status": "archive", "datestamp": "2023-08-22 00:59:57", "lastmod": "2023-10-17 20:25:17", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Kuang-Z", "name": { "family": "Kuang", "given": "Zhiming" } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Observed albedo decrease related to the spring snow retreat", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2000 The American Geophysical Union.\n\nPaper number 1999GL011116.\n\nReceived September 23, 1999; Revised February 21, 2000; Accepted March 9, 2000.\n\nThis research was supported by NASA grants NAG5-7230 and NAG5-7680. The authors are grateful to S. Byrne, M. Gerstell, R. Goody, S. Leroy, H. Wang, and one anonymous reviewer for useful discussion and comments.\n\nPublished - grl12653.pdf
", "abstract": "We study the impact of the spring snow retreat on albedo from 1979 to 1991 using the ultraviolet (UV) reflectivity measured by the Total Ozone Mapping Spectrometer (TOMS). Over the Northern Hemisphere (NH) snowy land area that was snow covered at least once during this period, we find a 1.5% decrease over the 13 years in the springtime UV reflectivity, related to a 5 \u00d7 10^6km^\u00b2 decrease in the satellite derived spring snow cover. About half of the reflectance decrease occurred over regions where snow cover and reflectance correlate at a 99% significance level. The 1.5% UV reflectivity decrease corresponds to a 1% decrease in the visible albedo over the snowy region, and a \u223c2 Wm^(\u22122) increase in the shortwave heating when averaged over the entire NH land. Based on observed interannual reflectivity changes over the entire NH snowy land area, our study provides a direct constraint on the shortwave forcing of the spring NH snow retreat.", "date": "2000-05-01", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "27", "number": "9", "publisher": "American Geophysical Union", "pagerange": "1299-1302", "id_number": "CaltechAUTHORS:20140821-103238205", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140821-103238205", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NAG5-7230" }, { "agency": "NASA", "grant_number": "NAG5-7680" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/1999GL011116", "primary_object": { "basename": "grl12653.pdf", "url": "https://authors.library.caltech.edu/records/r3wgb-raw15/files/grl12653.pdf" }, "resource_type": "article", "pub_year": "2000", "author_list": "Kuang, Zhiming and Yung, Yuk L." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/q3g9n-wak52", "eprint_id": 52881, "eprint_status": "archive", "datestamp": "2023-08-22 00:58:10", "lastmod": "2023-10-18 21:44:15", "type": "conference_item", "metadata_visibility": "show", "creators": { "items": [ { "id": "Lee-Anthony-Y-T", "name": { "family": "Lee", "given": "Anthony Y. T." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Moses-J-I", "name": { "family": "Moses", "given": "Julianne I." }, "orcid": "0000-0002-8837-0035" } ] }, "title": "Kinetics of hydrocarbons at low temperature: Suggestions based on photochemical models in the outer solar system", "ispublished": "unpub", "full_text_status": "restricted", "note": "\u00a9 2000 American Chemical Society.", "abstract": "Recent measurements of methyl radicals (CH_3) in the upper atmospheres of Saturn and Neptune by the Infrared Space Observatory (ISO) provide new constraints to photochemical model of hydrocarbon chemistry in the outer solar system, and the low-temperature hydrocarbon kinetics. The derived column abundances of CH_3 on Saturn above 10 mbar and Neptune above the 0.2 mbar\npressure level are (2.5-6.0) * 10^(13) cm^(-2) and (0.7-2.8) * 10^(13) cm^(-2), respectively. These observations imply a kinetically sensitive test to the measured and estimated hydrocarbon rate constants at low temperatures. We use the updated Caltech/JPL photochemical model, which incorporates hydrocarbon photochemistry, vertical molecular and bulk atmospheric eddy diffusion, and realistic radiative transfer modeling, to study the CH_3 abundances in the upper atmosphere of the giant planets (Jupiter, Saturn, Uranus, Neptune) and Titan.", "date": "2000-03-26", "date_type": "published", "publisher": "American Chemical Society", "id_number": "CaltechAUTHORS:20141216-133144921", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20141216-133144921", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "resource_type": "conference_item", "pub_year": "2000", "author_list": "Lee, Anthony Y. T.; Yung, Yuk L.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/g4c6q-q7239", "eprint_id": 9129, "eprint_status": "archive", "datestamp": "2023-08-21 20:55:28", "lastmod": "2023-10-16 21:55:46", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Weiss-B-P", "name": { "family": "Weiss", "given": "Benjamin P." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Nealson-K-H", "name": { "family": "Nealson", "given": "Kenneth H." }, "orcid": "0000-0001-5189-3732" } ] }, "title": "Atmospheric energy for subsurface life on Mars?", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2000 by the National Academy of Sciences. \n\nCommunicated by Richard M. Goody, Harvard University, Cambridge, MA, December 10, 1999 (received for review July 19, 1999). Article published online before print: Proc. Natl. Acad. Sci. USA, 10.1073/pnas.030538097. \n\nWe thank A. Haldemann, M. Allen, H. Holland, B. Jakosky, and E. Gaidos for helpful discussions. We also thank R. Goody for reviewing and communicating this work to PNAS. This research is supported in part by NASA Grant NAG5-4022 and the NASA Astrobiology Institute grant to the California Institute of Technology.\n\nPublished - WEIpnas00.pdf
", "abstract": "The location and density of biologically useful energy sources on Mars will limit the biomass, spatial distribution, and organism size of any biota. Subsurface Martian organisms could be supplied with a large energy flux from the oxidation of photochemically produced atmospheric H2 and CO diffusing into the regolith. However, surface abundance measurements of these gases demonstrate that no more than a few percent of this available flux is actually being consumed, suggesting that biological activity driven by atmospheric H2 and CO is limited in the top few hundred meters of the subsurface. This is significant because the available but unused energy is extremely large: for organisms at 30-m depth, it is 2,000 times previous estimates of hydrothermal and chemical weathering energy and far exceeds the energy derivable from other atmospheric gases. This also implies that the apparent scarcity of life on Mars is not attributable to lack of energy. Instead, the availability of liquid water may be a more important factor limiting biological activity because the photochemical energy flux can only penetrate to 100- to 1,000-m depth, where most H2O is probably frozen. Because both atmospheric and Viking lander soil data provide little evidence for biological activity, the detection of short-lived trace gases will probably be a better indicator of any extant Martian life.", "date": "2000-02-15", "date_type": "published", "publication": "Proceedings of the National Academy of Sciences of the United States of America", "volume": "97", "number": "4", "publisher": "National Academy of Sciences", "pagerange": "1395-1399", "id_number": "CaltechAUTHORS:WEIpnas00", "issn": "0027-8424", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:WEIpnas00", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NAG5-4022" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1073/pnas.030538097", "pmcid": "PMC26444", "primary_object": { "basename": "WEIpnas00.pdf", "url": "https://authors.library.caltech.edu/records/g4c6q-q7239/files/WEIpnas00.pdf" }, "resource_type": "article", "pub_year": "2000", "author_list": "Weiss, Benjamin P.; Yung, Yuk L.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/bmmr5-x4s72", "eprint_id": 48992, "eprint_status": "archive", "datestamp": "2023-08-22 14:14:58", "lastmod": "2023-10-17 20:35:43", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Cheng-Bing-Ming", "name": { "family": "Cheng", "given": "Bing-Ming" } }, { "id": "Chew-Eh-Piew", "name": { "family": "Chew", "given": "Eh Piew" } }, { "id": "Liu-Chin-Ping", "name": { "family": "Liu", "given": "Chin-Ping" } }, { "id": "Bahou-Mohammed", "name": { "family": "Bahou", "given": "Mohammed" } }, { "id": "Lee-Yaun-Pern", "name": { "family": "Lee", "given": "Yaun-Pern" } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Gerstell-M-F", "name": { "family": "Gerstell", "given": "M. F." } } ] }, "title": "Photo-induced fractionation of water isotopomers in the Martian atmosphere", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1999 The American Geophysical Union.\n\nReceived May 27, 1999; Revised July 20, 1999; Accepted August 6, 1999.\n\nPaper number 1999GL008367.\n\nThe authors thank H. Nair for computing Figure 2, and D. M. Kass, C. M. Miller and B. P. Weiss for valuable comments. This research was supported in part by NASA grant NAG5-4022 and NSF grant AST-9816409 to the California Institute of Technology.\n\nPublished - grl12231.pdf
", "abstract": "The history and size of the water reservoirs on early Mars can be constrained using isotopic ratios of deuterium to hydrogen. We present new laboratory measurements of the ultraviolet cross-sections of H_2O and its isotopomers, and modeling calculations in support of a photo-induced fractionation effect (PHIFE), that reconciles a discrepancy between past theoretical modeling and recent observations. This supports the hypothesis that Mars had an early warm atmosphere and has lost at least a 50-m global layer of water. Likely applications of PHIFE to other planetary atmospheres are sketched.", "date": "1999-12-15", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "26", "number": "24", "publisher": "American Geophysical Union", "pagerange": "3657-3660", "id_number": "CaltechAUTHORS:20140827-124624938", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140827-124624938", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NAG5-4022" }, { "agency": "NSF", "grant_number": "AST-9816409" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/1999GL008367", "primary_object": { "basename": "grl12231.pdf", "url": "https://authors.library.caltech.edu/records/bmmr5-x4s72/files/grl12231.pdf" }, "resource_type": "article", "pub_year": "1999", "author_list": "Cheng, Bing-Ming; Chew, Eh Piew; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/e082r-h8189", "eprint_id": 49006, "eprint_status": "archive", "datestamp": "2023-08-22 14:15:03", "lastmod": "2023-10-17 20:36:18", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Kass-D-M", "name": { "family": "Kass", "given": "David M." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Water on Mars: Isotopic constraints on exchange between the atmosphere and surface", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1999 The American Geophysical Union.\n\nReceived June 4, 1999; Revised July 20, 1999; Accepted September 27, 1999.\n\nPaper number 1999GL008372.\n\nWe thank V. Krasnopolsky for helpful comments. This research was supported by the Astrobiology Institute and NASA grant NAG5-4022 to the California Institute of Technology.\n\nPublished - grl12235.pdf
", "abstract": "Using a new measurement of the D/H fractionation efficiency and new estimates of the water loss, we calculate that Mars has the equivalent of a \u223c9 m global water layer in a reservoir that exchanges with the atmosphere. The measured D/H enrichment is about 5 times the terrestrial value, but without exchange, the atmosphere converges on an enrichment of 50 in about 0.5 Ma. Due to the large buffering reservoir and the rapid loss rate (10^(\u22123) pr-\u00b5m yr^(\u22121)), the small atmospheric reservoir, averaging 10 pr-\u00b5m, is unlikely to be in continuous isotopic equilibrium with the full 9 m exchangeable reservoir. Instead, it presumably equilibrates during periods of high obliquity; the atmospheric D/H ratio is expected to be enriched in between such periods. If isotopic exchange with a small (4 mm global layer) reservoir occurs under current conditions, it possible for the atmospheric D/H ratio to be within 10% of its long term equilibrium.", "date": "1999-12-15", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "26", "number": "24", "publisher": "American Geophysical Union", "pagerange": "3653-3656", "id_number": "CaltechAUTHORS:20140827-143313052", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140827-143313052", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA Astrobiology Institute" }, { "agency": "NASA", "grant_number": "NAG5-4022" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/1999GL008372", "primary_object": { "basename": "grl12235.pdf", "url": "https://authors.library.caltech.edu/records/e082r-h8189/files/grl12235.pdf" }, "resource_type": "article", "pub_year": "1999", "author_list": "Kass, David M. and Yung, Yuk L." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/ymref-8sb58", "eprint_id": 48987, "eprint_status": "archive", "datestamp": "2023-08-22 14:05:46", "lastmod": "2023-10-17 20:35:37", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Liao-Hong", "name": { "family": "Liao", "given": "Hong" } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Seinfeld-J-H", "name": { "family": "Seinfeld", "given": "John H." }, "orcid": "0000-0003-1344-4068" } ] }, "title": "Effects of aerosols on tropospheric photolysis rates in clear and cloudy atmospheres", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1999 by the American Geophysical Union. Received January 19, 1999; revised June 5, 1999; accepted June 8, 1999. \nPaper number 1999JD900409.\n\nThis work was supported by National Science Foundation grant ATM-9614105 and NASA grant NAG5-3553.\n\nPublished - jgrd6796.pdf
", "abstract": "The effect of aerosols on 14 tropospheric photolysis reactions is examined under noncloudy and cloudy sky conditions by using a detailed one-dimensional radiative transfer model. Pure (NH_4)_2SO_4, pure soot, and internal and external mixtures of the two aerosols, as well as mineral dust aerosol, are considered. Nonabsorbing aerosol generally enhances photolysis rates above and in the upper part of the aerosol layer in both noncloudy and cloudy atmospheres, with the enhancement effect reduced in the presence of clouds. In contrast, soot aerosol reduces photolysis rates under both noncloudy and cloudy sky conditions, with the reduction accentuated by a cloud layer. Mixtures of absorbing and nonabsorbing aerosols may produce enhancement or reduction in photolysis rates under clear sky conditions, whereas they generally reduce rates when a cloud is present. In the absence of cloud, sulfate aerosol at urban levels enhances tropospheric average photolysis rates from 11 to 18% for the 14 reactions studied; soot aerosol decreases tropospheric average rates from 6 to 11%. In the presence of a 500-m-thick stratus cloud, sulfate aerosol enhances each of 14 tropospheric average photolysis rates by about 5%; soot aerosol decreases tropospheric average photolysis rates from 9 to 19%.", "date": "1999-10-20", "date_type": "published", "publication": "Journal of Geophysical Research D", "volume": "104", "number": "D19", "publisher": "American Geophysical Union", "pagerange": "23697-23707", "id_number": "CaltechAUTHORS:20140827-111107356", "issn": "0148-0227", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140827-111107356", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "ATM-9614105" }, { "agency": "NASA", "grant_number": "NAG5-3553" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/1999JD900409", "primary_object": { "basename": "jgrd6796.pdf", "url": "https://authors.library.caltech.edu/records/ymref-8sb58/files/jgrd6796.pdf" }, "resource_type": "article", "pub_year": "1999", "author_list": "Liao, Hong; Yung, Yuk L.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/sj9q6-q4136", "eprint_id": 48996, "eprint_status": "archive", "datestamp": "2023-08-22 14:03:38", "lastmod": "2023-10-17 20:35:54", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Lunine-J-I", "name": { "family": "Lunine", "given": "Jonathan I." }, "orcid": "0000-0003-2279-4131" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Lorenz-R-D", "name": { "family": "Lorenz", "given": "Ralph D." }, "orcid": "0000-0001-8528-4644" } ] }, "title": "On the volatile inventory of Titan from isotopic abundances in nitrogen and methane", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 1999 Elsevier Science Ltd. Received 9 November 1998; received in revised form 1 February 1999; accepted 22 February 1999. Available online 24 November 1999. The first author is most grateful to Dr Angioletta\nCoradini for hosting his sabbatical at the Istituto di\nAstrofisica Spaziale, Rome, during the preparation of\nthis paper. Helpful and substantive referee suggestions,\nas well as those of Dr Daniel Gautier, improved the\nquality of the work. Support for the project and paper\nwere provided by the Consiglio Nazionale della\nRicerche and NASA's Atmospheres and Geoscience\nprograms.", "abstract": "We analyze recently published nitrogen and hydrogen isotopic data to constrain the initial volatile abundances on Saturn's giant moon Titan. The nitrogen data are interpreted in terms of a model of non-thermal escape processes that lead to enhancement in the heavier isotope. We show that these data do not, in fact, strongly constrain the abundance of nitrogen present in Titan's early atmosphere, and that a wide range of initial atmospheric masses (all larger than the present value) can yield the measured enhancement. The enrichment in deuterated methane is now much better determined than it was when Pinto et al. (1986. Nature 319, 388\u2013390) first proposed a photochemical mechanism to preferentially retain the deuterium. We develop a simple linear theory to provide a more reliable estimate of the relative dissociation rates of normal and deuterated methane. We utilize the improved data and models to compute initial methane reservoirs consistent with the observed enhancement. The result of this analysis agrees with an independent estimate for the initial methane abundance based solely on the present-day rate of photolysis and an assumption of steady state. This consistency in reservoir size is necessary but not sufficient to infer that methane photolysis has proceeded steadily over the age of the solar system to produce large quantities of less volatile organics. Our analysis indicates an epoch of early atmospheric escape of nitrogen, followed by a later addition of methane by outgassing from the interior. The results also suggest that Titan's volatile inventory came in part or largely from a circum-Saturnian disk of material more reducing than the surrounding solar nebula. Many of the ambiguities inherent in the present analysis can be resolved through Cassini\u2013Huygens data and a program of laboratory studies on isotopic and molecular exchange processes. The value of, and interest in, the Cassini\u2013Huygens data can be greatly enhanced if such a program were undertaken prior to the prime phase of the mission.", "date": "1999-10", "date_type": "published", "publication": "Planetary and Space Science", "volume": "47", "number": "10-11", "publisher": "Elsevier", "pagerange": "1291-1303", "id_number": "CaltechAUTHORS:20140827-134733578", "issn": "0032-0633", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140827-134733578", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Consiglio Nazionale della Ricerche" }, { "agency": "NASA Atmospheres and Geoscience programs" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/S0032-0633(99)00052-5", "resource_type": "article", "pub_year": "1999", "author_list": "Lunine, Jonathan I.; Yung, Yuk L.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/s8k51-75050", "eprint_id": 48999, "eprint_status": "archive", "datestamp": "2023-08-22 13:59:59", "lastmod": "2023-10-17 20:36:03", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Hsu-K-J", "name": { "family": "Hsu", "given": "Kuang-Jung" } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk Ling" }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Ozone Trend over Taiwan from TOMS Data", "ispublished": "pub", "full_text_status": "restricted", "keywords": "Total ozone, Trend, Ozone Trend over Taiwan from TOMS Data", "note": "\u00a9 1999 Chinese Geoscience Union. Manuscript received 24 September 1998, in final form 13 July 1999. The authors would like to thank Prof. H. H. Hsu for many helpful discussions. This study is supported by National Science Council of Taiwan under the Grant NSC 88-2111-M-002-012.", "abstract": "Ozone column data obtained from Nimbus 7 satellite instrument, TOMS, were analyzed. Total ozone data over Taiwan starts November 1978 till May 1993. Daily observations were changed into monthly data for trend analysis. First, spectral analyses were performed to find possible atmospheric movements. Significant peaks were found at periods of 6, 12, 19, and 29 months. The first two are due to seasonal variations. The last one corresponds to the quasi-biennial oscillation (QBO) in stratosphere. It is suggested that the 19-months period is the difference of the annual and the equatorial QBD frequencies.\n\n A linear regression model (LRM) described by Yang and Tung (J. of Geophysical Res. 100, 9091, 1995) were adapted to the deseasoned ozone data. Besides the QBD, the solar flux and ENSO are known to affect the amount of ozone in the Earth atmosphere. The 30-mbar Singapore wind and F10.7-cm solar flux were chosen to represent variations of QBD and solar flux, respectively. The estimated total ozone decreasing trends due to anthropogenic activities are 0.92 + - 0.46% and 1.77 + - 0.52% per decade over Taipei and Cheng-Kung, respectively. Increase in tropospheric production of ozone in Taipei may explain the lower trend in Taipei than that in Cheng-Kung. Estimated contributions from natural variables to the total ozone variations are: 3.2% and 2.8% form QBD maximum to minimum; 2.0% and 2.3% per 100 solar units for Taipei and Cheng-Kung, respectively. Influence from ENSO seems to be insignificant. Comparison with ground total ozone stations will be discussed.", "date": "1999-09", "date_type": "published", "publication": "Terrestrial Atmospheric and Oceanic Sciences", "volume": "10", "number": "3", "publisher": "Chinese Geoscience Union", "pagerange": "619-632", "id_number": "CaltechAUTHORS:20140827-140013357", "issn": "1017-0839", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140827-140013357", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "National Science Council of Taiwan", "grant_number": "NSC 88-2111-M-002-012" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "resource_type": "article", "pub_year": "1999", "author_list": "Hsu, Kuang-Jung and Yung, Yuk Ling" }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/8x79b-h6y74", "eprint_id": 48676, "eprint_status": "archive", "datestamp": "2023-08-22 13:56:00", "lastmod": "2023-10-17 19:31:53", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Y. L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Shia-C", "name": { "family": "Shia", "given": "C." } }, { "id": "Herman-R-L", "name": { "family": "Herman", "given": "R. L." } } ] }, "title": "Is the biomass burning source of CO decreasing?", "ispublished": "pub", "full_text_status": "restricted", "keywords": "Carbon monoxide; Methane; Trend; Biomass burning", "note": "\u00a9 1999 Elsevier Science Ltd. Received 16 April 1998, Accepted 15 December 1998, Available online 27 January 2000. We thank J.P. Pinto, J. Wang, M.O. Andreae, E.J. Moyer, and two anonymous reviewers for helpful comments, and E.J. Dlugokencky and P.C. Novelli of NOAA\u00b1CMDL for the use of CH_4 and CO data from the NOAA\u00b1CMDL global flask sampling network. Supported by NASA grant NAG1-1806 to the California Institute of Technology. Contribution 5765 from the Division of\nGeological and Planetary Sciences, California Institute\nof Technology.", "abstract": "To investigate secular changes in CO and CH_4, we examined monthly means of tropospheric measurements made from samples collected at 19 fixed sites in the National Oceanic and Atmospheric Administration (NOAA) Climate Monitoring and Diagnostics Laboratory (CMDL) global cooperative flask sampling network. The CH_4 data are available for the period 1984\u20131995. A somewhat shorter time series is available for CO (1989\u20131995). The data were analyzed to extract a consistent pattern of change in time and in latitude. The most important preliminary finding is that the patterns of CO and CH_4 change appear to resemble that of biomass burning. That is, there is maximum change during local spring in both northern and southern hemispheres. If we attribute a significant part of the change in CH_4 trend (3\u20136 ppb/yr) to biomass burning, the corresponding change in CO is approximately 2\u20135 ppb/yr. This would explain the bulk of the observed change in CO (4\u20137 ppb/yr).", "date": "1999-08", "date_type": "published", "publication": "Chemosphere: Global Change Science", "volume": "1", "number": "1-3", "publisher": "Elsevier", "pagerange": "83-90", "id_number": "CaltechAUTHORS:20140819-093937810", "issn": "0045-6535", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140819-093937810", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NAG1-1806" } ] }, "other_numbering_system": { "items": [ { "id": "5765", "name": "Caltech Division of Geological and Planetary Sciences" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/S1465-9972(99)00015-X", "resource_type": "article", "pub_year": "1999", "author_list": "Yung, Y. L.; Shia, C.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/av0h8-8q876", "eprint_id": 46506, "eprint_status": "archive", "datestamp": "2023-08-22 13:55:53", "lastmod": "2023-10-26 19:47:57", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Herman-R-L", "name": { "family": "Herman", "given": "R. L." } }, { "id": "Webster-C-R", "name": { "family": "Webster", "given": "C. R." } }, { "id": "May-R-D", "name": { "family": "May", "given": "R. D." } }, { "id": "Scott-D-C", "name": { "family": "Scott", "given": "D. C." } }, { "id": "Hu-H", "name": { "family": "Hu", "given": "H." } }, { "id": "Moyer-E-J", "name": { "family": "Moyer", "given": "E. J." } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Hanisco-T-F", "name": { "family": "Hanisco", "given": "T. F." }, "orcid": "0000-0001-9434-8507" }, { "id": "Lanzendorf-E-J", "name": { "family": "Lanzendorf", "given": "E. J." } }, { "id": "Salawitch-R-J", "name": { "family": "Salawitch", "given": "R. J." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Y. L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Margitan-J-J", "name": { "family": "Margitan", "given": "J. J." } }, { "id": "Bui-T-P", "name": { "family": "Bui", "given": "T. P." } } ] }, "title": "Measurements of CO in the upper troposphere and lower stratosphere", "ispublished": "pub", "full_text_status": "restricted", "keywords": "Carbon monoxide; In situ measurement; Upper troposphere; Lower stratosphere", "note": "\u00a9 1999 Elsevier Science Ltd. \n\nReceived 16 April 1998; accepted 15 September 1998. \n\nWe thank J.P. Pinto, S.C. Wofsy, and two anonymous reviewers for helpful comments; B.L. Gary for providing tropopause heights; E.J. Hintsa and E.M. Weinstock for H_(2)O data; K.H. Rosenlof for providing tropical heating rates; G.J. Flesch, L. Kroll, K. Modarress, and M. Tuchscherer for laboratory and field support of the ALIAS instrument; J.W. Elkins and R. Myers for gas standards; the ER-2 pilots and crew; and A.E. Kulawik for computational assistance. This work was supported by NASA's Upper Atmospheric Research Program (UARP) and the Atmospheric Effects of Aviation Project (AEAP). Part of the research described in this paper was carried out by the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration. Division of Geological and Planetary Sciences, California Institute of Technology, Contribution 5764.", "abstract": "In situ measurements of CO were made in the upper troposphere and lower stratosphere (7\u201321 km altitude) with the Jet Propulsion Laboratory (JPL) Aircraft Laser Infrared Absorption Spectrometer (ALIAS) on 58 flights of the NASA ER-2 aircraft from October 1995 through September 1997, between 90\u00b0N and 3\u00b0S latitude. Measured upper tropospheric CO was variable and typically ranged between 55 and 115 ppb, except for higher values over Alaska during summer 1997. Tropical stratospheric CO ranged from 58 \u00b1 5 ppb at the tropopause to 12 \u00b1 2 ppb above 20 km, having similar profiles in all seasons of the year. The tropical profile is reproduced by a simple Lagrangian box model of tropical ascent using measured CH4 and OH concentrations, Cl and O(^1D) concentrations from a photochemical model, and diabatic heating rates from a radiative heating model. From measured CO, quasi-horizontal mixing between the tropical and mid-latitude lower stratosphere is inferred to be rapid in the region between 400 K and 450 K potential temperature (altitudes less than 20 km).", "date": "1999-08", "date_type": "published", "publication": "Chemosphere: Global Change Science", "volume": "1", "number": "1-3", "publisher": "Elsevier", "pagerange": "173-183", "id_number": "CaltechAUTHORS:20140625-113609378", "issn": "0045-6535", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140625-113609378", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA/JPL/Caltech" } ] }, "other_numbering_system": { "items": [ { "id": "5764", "name": "Caltech Division of Geological and Planetary Sciences" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/S1465-9972(99)00008-2", "resource_type": "article", "pub_year": "1999", "author_list": "Herman, R. L.; Webster, C. R.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/fdh7b-4gr45", "eprint_id": 48671, "eprint_status": "archive", "datestamp": "2023-08-22 13:03:14", "lastmod": "2023-10-17 19:31:32", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Herman-R-L", "name": { "family": "Herman", "given": "R. L." } }, { "id": "Scott-D-C", "name": { "family": "Scott", "given": "D. C." } }, { "id": "Webster-C-R", "name": { "family": "Webster", "given": "C. R." } }, { "id": "May-R-D", "name": { "family": "May", "given": "R. D." } }, { "id": "Moyer-E-J", "name": { "family": "Moyer", "given": "E. J." } }, { "id": "Salawitch-R-J", "name": { "family": "Salawitch", "given": "R. J." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Y. L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Toon-G-C", "name": { "family": "Toon", "given": "G. C." }, "orcid": "0000-0003-4174-7541" }, { "id": "Sen-B", "name": { "family": "Sen", "given": "B." } }, { "id": "Margitan-J-J", "name": { "family": "Margitan", "given": "J. J." } }, { "id": "Rosenlof-K-H", "name": { "family": "Rosenlof", "given": "K. H." } }, { "id": "Michelsen-H-A", "name": { "family": "Michelsen", "given": "H. A." } }, { "id": "Elkins-J-W", "name": { "family": "Elkins", "given": "J. W." } } ] }, "title": "Tropical entrainment time scales inferred from stratospheric N_2O and CH_4 observations", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1998 American Geophysical Union.\n\nReceived March 11, 1998; revised June 8, 1998; accepted June 15, 1998.\n\nWe thank C. M. Volk, F. L. Moore, K. Minschwaner, and two anonymous reviewers for helpful comments, H. V\u00f6mel for temperature data, and A. E. Kulawik for computational\nassistance. We also thank W. H. Brune, G. J. Flesch, L. Kroll, M. Tuchscherer, J. Riccio, R. Howe, B. Wilson, J. Landeros, and the National Scientific Balloon Facility (NSBF) for assistance. Support for this work and the OMS balloon flights was provided by NASA's Upper Atmospheric Research Program and Atmospheric Effects of Aviation\nProject. H.A.M. was supported by NASA grant NAS1-96022. Part of the research described in this paper was carried out by the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration. Division of Geological\nand Planetary Sciences, California Institute of Technology, Contribution 5762.\n\nPublished - grl11342.pdf
", "abstract": "Simultaneous in situ measurements of N_2O and CH_4 were made with a tunable diode laser spectrometer (ALIAS II) aboard the Observations from the Middle Stratosphere (OMS) balloon platform from New Mexico, Alaska, and Brazil during 1996 and 1997. We find different compact relationships of CH_4 with N_2O in the tropics and extra-tropics because mixing is slow between these regions. Transport into the extra-tropics from the tropics or the polar vortex leads to deviations from the normal compact relationship. We use measured N_2O and CH_4 and a simple model to quantify entrainment of mid-latitude stratospheric air into the tropics. The entrainment time scale is estimated to be 16 (+17, \u22128) months for altitudes between 20 and 28 km. The fraction of tropical air entrained from the extra-tropical stratosphere is 50% (+18%, \u221230%) at 20 km, increasing to 78% (+11%, \u221219%) at 28 km.", "date": "1998-08-01", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "25", "number": "15", "publisher": "American Geophysical Union", "pagerange": "2781-2784", "id_number": "CaltechAUTHORS:20140819-085416821", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140819-085416821", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA Upper Atmosphere Research Program" }, { "agency": "NASA Atmospheric Effects of Aviation Project" }, { "agency": "NASA", "grant_number": "NAS1-96022" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/98GL02109", "primary_object": { "basename": "grl11342.pdf", "url": "https://authors.library.caltech.edu/records/fdh7b-4gr45/files/grl11342.pdf" }, "resource_type": "article", "pub_year": "1998", "author_list": "Herman, R. L.; Scott, D. C.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/fane9-b3s49", "eprint_id": 52094, "eprint_status": "archive", "datestamp": "2023-08-22 12:56:03", "lastmod": "2023-10-18 19:33:27", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Kass-D-M", "name": { "family": "Kass", "given": "David M." } } ] }, "title": "Deuteronomy?: A Puzzle of Deuterium and Oxygen on Mars", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 1998 American Association for the Advancement of Science.", "abstract": "Mars is covered by channels that were likely formed by liquid water sometime in its past. Among the very few available clues to a wetter and warmer ancient climate on Mars are the isotopic signatures left by processes that have modified its atmosphere over time. In their Research Commentary, Yung and Kass discuss two sets of results in the same issue: Krasnopolsky et al . have used the Hubble Space Telescope to detect the presence of deuterium in the upper atmosphere of Mars, and Farquhar et al . report measurements of the Martian meteorite ALH84001 showing that the oxygen isotopes in the carbonate are fractionated with respect to silicate minerals. The findings suggest the presence of chemical processes operating in Mars' atmosphere that have yet to be fully understood.", "date": "1998-06-05", "date_type": "published", "publication": "Science", "volume": "280", "number": "5369", "publisher": "American Association for the Advancement of Science", "pagerange": "1545-1546", "id_number": "CaltechAUTHORS:20141124-104505050", "issn": "0036-8075", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20141124-104505050", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1126/science.280.5369.1545", "resource_type": "article", "pub_year": "1998", "author_list": "Yung, Yuk L. and Kass, David M." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/890ta-3nz52", "eprint_id": 48672, "eprint_status": "archive", "datestamp": "2023-08-22 12:49:16", "lastmod": "2023-10-17 19:31:35", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Kuang-Zhiming", "name": { "family": "Kuang", "given": "Zhiming" } }, { "id": "Jiang-Yibo", "name": { "family": "Jiang", "given": "Yibo" }, "orcid": "0000-0001-6711-7260" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Cloud optical thickness variations during 1983-1991: Solar cycle or ENSO?", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1998 American Geophysical Union.\n\nReceived October 15, 1997; revised January 7, 1998; accepted January 16, 1998.\n\nWe thank R. M. Goody, R. D. Haskins, K. Hsu, C. B. Leovy, K. K. Tung, B. Tinsley, W. Rossow and two anonymous referees for valuable insights. We are especially grateful to the referee who directed us to the paper by Menzel et al. [1997]. This research was supported in part by NASA grant NAGl-1806 to the California Institute of Technology.\n\nPublished - grl10952.pdf
", "abstract": "Based on a detailed analysis of the cloud data obtained by the International Satellite Cloud Climatology Project (ISCCP) in the years 1983\u20131991, we show that besides the reported 3% variation in global cloudiness (Svensmark and Friis-Christensen, 1997), the global mean cloud optical thickness (MCOT) also has significant variation which is out of phase with that of the global cloudiness. The combined effect of the two opposing variations may be a null effect on the cloud reflectivity. These results are consistent with the Total Ozone Mapping Spectrometer (TOMS) reflectivity measurements. The MCOT variation is further shown to be correlated with both the solar cycle and the ENSO cycle. Our present analysis cannot distinguish which of the above two provides better correlation, although independent data from the High resolution Infrared Radiation Sounder (HIRS) from 1990 to 1996 favor the solar cycle. Future data are needed to identify the true cause of these changes.", "date": "1998-05-01", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "25", "number": "9", "publisher": "American Geophysical Union", "pagerange": "1415-1417", "id_number": "CaltechAUTHORS:20140819-085510052", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140819-085510052", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NAG1-1806" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/98GL00471", "primary_object": { "basename": "grl10952.pdf", "url": "https://authors.library.caltech.edu/records/890ta-3nz52/files/grl10952.pdf" }, "resource_type": "article", "pub_year": "1998", "author_list": "Kuang, Zhiming; Jiang, Yibo; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/ggh5w-ww035", "eprint_id": 48661, "eprint_status": "archive", "datestamp": "2023-08-22 12:42:05", "lastmod": "2023-10-17 19:31:05", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Jiang-Yibo", "name": { "family": "Jiang", "given": "Yibo" }, "orcid": "0000-0001-6711-7260" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Douglass-Anne-R", "name": { "family": "Douglass", "given": "Anne R." } }, { "id": "Tung-Ka-Kit", "name": { "family": "Tung", "given": "K. K." }, "orcid": "0000-0001-8667-7167" } ] }, "title": "The standard deviation of column ozone from the zonal mean", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1998 American Geophysical Union.\n\nWe thank M. Allen, L. Hood, A . Ingersoll, J. Kaye, R. Salawitch, R. Stolarski, and R. Zurek for valuable comments. We are grateful to M. Ko and two anonymous referees for focusing and shortening the paper. This work was supported by\nNASA grant NAGl-1806 to the California Institute of Technology. Contribution number 5754 from the Division of Geological and Planetary Sciences, California Institute of Technology.\n\nPublished - grl10910.pdf
", "abstract": "The standard deviation of column ozone from the zonal mean (COSDZ) provides a measure of the longitudinal inhomogeneity in ozone and dynamical wave activities in the atmosphere. Using the Total Ozone Mapping Spectrometer (TOMS) data, we obtain latitude-season maps of COSDZ that are representative of a dynamically quiet year (1987) and a dynamically active year (1992). The spatial and temporal patterns of COSDZ show considerable similarity to the standard deviation of the 50 mb geopotential heights from the zonal mean. We point out that the simulation of this quantity by three-dimensional (3-D) models could provide a sensitive check of wave activities in the stratosphere that are responsible for ozone transport. Comparison between the observed COSDZ and the simulations of the GSFC 3-D model of ozone reveals major discrepancies between data and model in the tropical stratosphere.", "date": "1998-03-15", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "25", "number": "6", "publisher": "American Geophysical Union", "pagerange": "911-914", "id_number": "CaltechAUTHORS:20140818-132951042", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140818-132951042", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NAG1-1806" } ] }, "other_numbering_system": { "items": [ { "id": "5754", "name": "Caltech Division of Geological and Planetary Sciences" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/98GL00329", "primary_object": { "basename": "grl10910.pdf", "url": "https://authors.library.caltech.edu/records/ggh5w-ww035/files/grl10910.pdf" }, "resource_type": "article", "pub_year": "1998", "author_list": "Jiang, Yibo; Yung, Yuk L.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/m0xf7-49n47", "eprint_id": 48668, "eprint_status": "archive", "datestamp": "2023-08-22 12:23:55", "lastmod": "2023-10-17 19:31:24", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Jiang-Yibo", "name": { "family": "Jiang", "given": "Yibo" }, "orcid": "0000-0001-6711-7260" }, { "id": "Liao-Hong", "name": { "family": "Liao", "given": "Hong" } }, { "id": "Gerstell-M-F", "name": { "family": "Gerstell", "given": "M. F." } } ] }, "title": "Enhanced UV penetration due to ozone cross-section changes induced by doubling", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1997 American Geophysical Union.\n\nReceived July 17, 1997; revised November 4, 1997; accepted November 7, 1997.\n\nWe thank A. P. Ingersoll, M. Allen, J. Kaye, D. V. Michelangeli, S. Sander for valuable comments. We are\ngrateful to M. Ko and two anonymous referees for suggestions on focusing and shortening the paper. This research is supported by NASA grant NAG1-1806 to the California Institute of Technology. Contribution number 5674 from the Division of Geological and Planetary Sciences, California Institute of Technology.\n\nPublished - grl10640.pdf
", "abstract": "Models predict that CO_2 doubling in the atmosphere cools the stratosphere by as much as 10\u00b0C. We argue that this effect alone, through the temperature dependence of the ozone spectrum, can result in an increase of a few percent in UV-B (280\u2013320 nm) penetration at the Earth's surface. The increase in Erythema-weighted UV radiation is about 1%. Future spectral observations of UV at the surface could distinguish this effect from any result of changes in ozone abundance.", "date": "1997-12-15", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "24", "number": "24", "publisher": "American Geophysical Union", "pagerange": "3229-3231", "id_number": "CaltechAUTHORS:20140819-085116845", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140819-085116845", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NAG1-1806" } ] }, "other_numbering_system": { "items": [ { "id": "5674", "name": "Caltech Division of Geological and Planetary Sciences" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/97GL03311", "primary_object": { "basename": "grl10640.pdf", "url": "https://authors.library.caltech.edu/records/m0xf7-49n47/files/grl10640.pdf" }, "resource_type": "article", "pub_year": "1997", "author_list": "Yung, Yuk L.; Jiang, Yibo; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/ezt3c-g2c77", "eprint_id": 47425, "eprint_status": "archive", "datestamp": "2023-09-15 04:47:27", "lastmod": "2023-10-23 21:09:51", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Miller-C-E", "name": { "family": "Miller", "given": "Charles E." }, "orcid": "0000-0002-9380-4838" } ] }, "title": "Isotopic fractionation of stratospheric nitrous oxide", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 1997 American Association for the Advancement of Science\n\nReceived 11 August 1997; accepted 9 October 1997.\n\nWe thank K. Boering, H. Craig, W. DeMore, R. Friedl,\nY. Jiang, J. Kaye, T. Rahn, S. Sander, M. Thiemens,\nand M. Wahlen for valuable discussions and inputs.\nC.E.M. thanks the National Research Council for a\nNASA Jet Propulsion Laboratory Research Associateship.\nThis research was supported in part by\nNASA grant NAG1-1806 to the California Institute of\nTechnology.", "abstract": "We propose an isotopic fractionation mechanism, based on photolytic destruction, to explain the ^(15)N/^(14)N and ^(18)O/^(16)O fractionation of stratospheric nitrous oxide (N_2O) and reconcile laboratory experiments with atmospheric observations. The theory predicts that (i) the isotopomers ^(15)N^(14)N^(16)O and ^(14)N^(15)N^(16)O have very different isotopic fractionations in the stratosphere, and (ii) laboratory photolysis experiments conducted at 205 nanometers should better simulate the observed isotopic fractionation of stratospheric N_2O. Modeling results indicate that there is no compelling reason to invoke a significant chemical source of N_2O in the middle atmosphere and that individual N_2O isotopomers might be useful tracers of stratospheric air parcel motion.", "date": "1997-12-05", "date_type": "published", "publication": "Science", "volume": "278", "number": "5344", "publisher": "American Association for the Advancement of Science", "pagerange": "1778-1780", "id_number": "CaltechAUTHORS:20140723-110519108", "issn": "0036-8075", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140723-110519108", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "National Research Council" }, { "agency": "NASA", "grant_number": "NAG1-1806" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1126/science.278.5344.1778", "resource_type": "article", "pub_year": "1997", "author_list": "Yung, Yuk L. and Miller, Charles E." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/vt9wk-7ay08", "eprint_id": 48684, "eprint_status": "archive", "datestamp": "2023-08-22 11:59:45", "lastmod": "2023-10-17 19:32:27", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Y. L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Nair-H", "name": { "family": "Nair", "given": "H." } }, { "id": "Gerstell-M-F", "name": { "family": "Gerstell", "given": "M. F." } } ] }, "title": "CO_2 Greenhouse in the Early Martian Atmosphere: SO_2 Inhibits Condensation", "ispublished": "pub", "full_text_status": "restricted", "keywords": "Mars; climate; atmosphere; evolution; greenhouse", "note": "\u00a9 1997 by Academic Press. Received September 19, 1996; revised June 23, 1997. We thank Dave Crisp and Yibo Jiang for valuable inputs to the paper, and Larry Trafton and an anonymous reviewer for useful comments. This work was supported by NASA Grant NAGW-4849 to the California Institute of Technology. Contribution number 5751 from the Division of Geological and Planetary Sciences, California Institute of Technology.", "abstract": "Many investigators of the early martian climate have suggested that a dense carbon dioxide atmosphere was present and warmed the surface above the melting point of water (J. B. Pollack, J. F. Kasting, S. M. Richardson, and K. Poliakoff 1987.Icarus71,203\u2013224). However, J. F. Kasting (1991.Icarus94,1\u201313) pointed out that previous thermal models of the primitive martian atmosphere had not considered the condensation of CO_2. When this effect was incorporated, Kasting found that CO_2 by itself is inadequate to warm the surface.\n\nSO_2 absorbs strongly in the near UV region of the solar spectrum. While a small amount of SO_2 may have a negligible effect by itself on the surface temperature, it may have significantly warmed the middle atmosphere of early Mars, much as ozone warms the terrestrial stratosphere today. If this region is kept warm enough to inhibit the condensation of CO_2, then CO_2 remains a viable greenhouse gas. Our preliminary radiative modeling shows that the addition of 0.1 ppmv of SO_2 in a 2 bar CO_2 atmosphere raises the temperature of the middle atmosphere by approximately 10 degrees, so that the upper atmosphere in a 1D model remains above the condensation temperature of CO_2. In addition, this amount of SO_2 in the atmosphere provides an effective UV shield for a hypothetical biosphere on the martian surface.", "date": "1997-11", "date_type": "published", "publication": "Icarus", "volume": "130", "number": "1", "publisher": "Elsevier", "pagerange": "222-224", "id_number": "CaltechAUTHORS:20140819-113543746", "issn": "0019-1035", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140819-113543746", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NAGW-4849" } ] }, "other_numbering_system": { "items": [ { "id": "5751", "name": "Caltech Division of Geological and Planetary Sciences" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1006/icar.1997.5808", "resource_type": "article", "pub_year": "1997", "author_list": "Yung, Y. L.; Nair, H.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/51dww-x8v68", "eprint_id": 46597, "eprint_status": "archive", "datestamp": "2023-08-22 11:45:47", "lastmod": "2023-10-26 19:51:56", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Jaegl\u00e9-L", "name": { "family": "Jaegl\u00e9", "given": "L." } }, { "id": "Webster-C-R", "name": { "family": "Webster", "given": "C. R." } }, { "id": "May-R-D", "name": { "family": "May", "given": "R. D." } }, { "id": "Scott-D-C", "name": { "family": "Scott", "given": "D. C." } }, { "id": "Stimpfle-R-M", "name": { "family": "Stimpfle", "given": "R. M." } }, { "id": "Kohn-D-W", "name": { "family": "Kohn", "given": "D. W." } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Hanisco-T-F", "name": { "family": "Hanisco", "given": "T. F." }, "orcid": "0000-0001-9434-8507" }, { "id": "Cohen-R-C", "name": { "family": "Cohen", "given": "R. C." }, "orcid": "0000-0001-6617-7691" }, { "id": "Proffitt-M-H", "name": { "family": "Proffitt", "given": "M. H." } }, { "id": "Kelly-K-K", "name": { "family": "Kelly", "given": "K. K." } }, { "id": "Elkins-J-W", "name": { "family": "Elkins", "given": "J." } }, { "id": "Baumgardner-D", "name": { "family": "Baumgardner", "given": "D." } }, { "id": "Dye-J-E", "name": { "family": "Dye", "given": "J. E." } }, { "id": "Wilson-J-C", "name": { "family": "Wilson", "given": "J. C." } }, { "id": "Pueschel-R-F", "name": { "family": "Pueschel", "given": "R. F." } }, { "id": "Chan-K-R", "name": { "family": "Chan", "given": "K. R." } }, { "id": "Salawitch-R-J", "name": { "family": "Salawitch", "given": "R. J." } }, { "id": "Tuck-A-F", "name": { "family": "Tuck", "given": "A. F." } }, { "id": "Hovde-S-J", "name": { "family": "Hovde", "given": "S. J." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Y. L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Evolution and stoichiometry of heterogeneous processing in the Antarctic stratosphere", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1997 American Geophysical Union. \n\nManuscript Accepted: 27 March 1997; Manuscript Received: 20 March 1996. \n\nThe authors would like to thank H. Nair for providing the original modifications to the photochemical Lagrangian code. K. Carslaw made available his code for ternary solution growth. We thank D. Fahey for the ASHOE/MAESA NO and NO_y data, E. Keim and L. Del Negro for valuable discussions, and L. Mickley for helpful comments. The authors also thank two reviewers for their comments.\nAdditional field operations support of ALIAS was provided by\nM. Tuchscherer and G. Flesch. Part of the research described in this paper was carried out by the Jet Propulsion Laboratory, California Institute of Technology, under contract with the National Aeronautics and Space Administration (NASA). This research is also supported in part by NASA grant NAGW-413 to the California Institute of Technology.\n\nPublished - jgrd5093.pdf
", "abstract": "Simultaneous in situ measurements of HCl and ClO have been made for the first time in the southern hemisphere, allowing a systematic study of the processes governing chlorine activation between 15 and 20 km in the 1994 Antarctic winter. Data for several other gases (O_3, NO, NO_y, OH, HO_2, N_(2)O, CH_4, CO, H_(2)O, CFCs), particulates, and meteorological parameters were collected from the ER-2 aircraft out of New Zealand as part of the 1994 Airborne Southern Hemisphere Ozone Experiment/Measurements of Atmospheric Effects of Stratospheric Aircraft (ASHOE/MAESA) campaign. Observations from the ER-2 in the fall (April\u2013May), prior to polar night, show that chlorine activation begins with 60\u201375% of inorganic chlorine as HCl. By midwinter (July\u2013August), near-total removal of HCl is observed. The wintertime loss of HCl in air recently exposed to extreme temperatures is found to be correlated with high levels of reactive chlorine (ClO and its dimer, Cl_(2)O_2) in the linear fashion expected from the stoichiometry of the heterogeneous reaction of hydrochloric acid with chlorine nitrate on polar stratospheric clouds (PSCs): HCl + ClONO_2 \u2192 Cl_2 + HNO_3. To constrain the role of different heterogeneous reactions and PSC types, we have used a photochemical trajectory model which includes heterogeneous sulfate and PSC chemistry. Model calculations of the evolution of reactive gases are compared with the in situ observations. In addition, simultaneous measurements of OH and HO_2 are used as a diagnostic for the occurrence of the heterogeneous reaction HOCl + HCl \u2192 Cl_2 + H_(2)O, which contributes to suppressed levels of HO_x inside the vortex. It is shown that the amount of chlorine activation is not strongly dependent on the composition of PSCs. However, HO_x levels exhibit different signatures depending on the type of heterogeneous surfaces that affected chlorine activation. Furthermore, this analysis implies that in the edge region of the Antarctic vortex, the observed near-total removal of HCl can result from latitudinal excursions of air parcels in and out of sunlight during the winter, which photochemically resupply HOCl and ClONO_2 as oxidation partners for HCl.", "date": "1997-06-20", "date_type": "published", "publication": "Journal of Geophysical Research D", "volume": "102", "number": "D11", "publisher": "American Geophysical Union", "pagerange": "13235-13253", "id_number": "CaltechAUTHORS:20140701-103116252", "issn": "0148-0227", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140701-103116252", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NAGW-413" }, { "agency": "NASA/JPL/Caltech" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/97JD00935", "primary_object": { "basename": "jgrd5093.pdf", "url": "https://authors.library.caltech.edu/records/51dww-x8v68/files/jgrd5093.pdf" }, "resource_type": "article", "pub_year": "1997", "author_list": "Jaegl\u00e9, L.; Webster, C. R.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/zw406-8j038", "eprint_id": 48675, "eprint_status": "archive", "datestamp": "2023-08-22 11:44:02", "lastmod": "2023-10-17 19:31:50", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Jiang-Yibo", "name": { "family": "Jiang", "given": "Yibo" }, "orcid": "0000-0001-6711-7260" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Sander-S-P", "name": { "family": "Sander", "given": "Stanley P." }, "orcid": "0000-0003-1424-3620" } ] }, "title": "Detection of tropospheric ozone by remote sensing from the ground", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 1997 Elsevier Science Ltd. Received 18 July 1996, Available online 16 May 1998. We thank R. S. Stolarski, R. Cageao, M. Allen, R. McPeters, M. Newchurch, and J.-H. Kim for\nvaluable comments. This work was supported by National Science Foundation grant ATM 9526209 and NASA grant\nNAGI-1806 to the California Institute of Technology. Contribution number 5674 from the Division of Geological and\nPlanetary Sciences, California Institute of Technology. After this work was completed, it was pointed out to us by\nR. McPeters that similar ideas were proposed by Green et al.", "abstract": "Due to larger multiple scattering effects in the troposphere compared to that in the stratosphere, the optical path of tropospheric ozone is markedly enhanced (as compared with that of stratospheric ozone) in the Huggins bands from 310 to 345 nm. Model study of the direct and diffuse solar fluxes on the ground shows differences between tropospheric and stratospheric ozone. The characteristic signature of tropospheric ozone enables us to distinguish a change in troposheric ozone from that of stratospheric ozone. A simple retrieval algorithm is used to recover the tropospheric column ozone from simulated data.", "date": "1997-06", "date_type": "published", "publication": "Journal of Quantitative Spectroscopy and Radiative Transfer", "volume": "57", "number": "6", "publisher": "Elsevier", "pagerange": "811-818", "id_number": "CaltechAUTHORS:20140819-093219098", "issn": "0022-4073", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140819-093219098", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "ATM 9526209" }, { "agency": "NASA", "grant_number": "NAG1-1806" } ] }, "other_numbering_system": { "items": [ { "id": "5674", "name": "Caltech Division of Geological and Planetary Sciences" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/S0022-4073(96)00145-8", "resource_type": "article", "pub_year": "1997", "author_list": "Jiang, Yibo; Yung, Yuk L.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/68beq-v2359", "eprint_id": 48666, "eprint_status": "archive", "datestamp": "2023-08-22 11:42:20", "lastmod": "2023-10-17 19:31:16", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Lee-Anthony-Y-T", "name": { "family": "Lee", "given": "Anthony Y. T." } }, { "id": "Irion-F-W", "name": { "family": "Irion", "given": "Fredrick W." } }, { "id": "DeMore-W-B", "name": { "family": "DeMore", "given": "William B." } }, { "id": "Wen-Jason-C", "name": { "family": "Wen", "given": "Jason C." } } ] }, "title": "Carbon dioxide in the atmosphere: Isotopic exchange with ozone and its use as a tracer in the middle atmosphere", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1997 by the American Geophysical Union. \n\nReceived September 27, 1996; revised January 23, 1997; accepted February 13, 1997. We thank M. Allen, K. Boering, S. Cliff, H. Craig, J. Kaye, K. Mauersberger, E. Moyer, and M. Thiemens for helpful discussions and Y. Jiang for assistance with the manuscript. This research is partly supported by NASA grant NAGW-413 to the California Institute of Technology and by the Jet Propulsion Laboratory\nunder contract to NASA; Division of Geological and Planetary\nSciences of the California Institute of Technology \ncontribution 5750.\n\nPublished - jgrd5003.pdf
", "abstract": "Atmospheric heavy ozone is enriched in the isotopes ^(18)O and ^(17)O. The magnitude of this enhancement, of the order of 100\u2030, is very large compared with that commonly known in atmospheric chemistry and geochemistry. The heavy oxygen atom in heavy ozone is therefore useful as a tracer of chemical species and pathways that involve ozone or its derived products. As a test of the isotopic exchange reactions, we successfully carry out a series of numerical experiments to simulate the results of the laboratory experiments performed by Wen and Thiemens [1993] on ozone and CO_2. A small discrepancy between the experimental and the model values for ^(17)O exchange is also revealed. The results are used to compute the magnitude of isotopic exchange between ozone and carbon dioxide via the excited atom O(^1D) in the middle atmosphere. The model for ^(18)O is in good agreement with the observed values.", "date": "1997-05-20", "date_type": "published", "publication": "Journal of Geophysical Research D", "volume": "102", "number": "D9", "publisher": "American Geophysical Union", "pagerange": "10857-10866", "id_number": "CaltechAUTHORS:20140819-081901864", "issn": "0148-0227", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140819-081901864", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NAGW-413" }, { "agency": "NASA/JPL/Caltech" } ] }, "other_numbering_system": { "items": [ { "id": "5750", "name": "Caltech Division of Geological and Planetary Sciences" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/97JD00528", "primary_object": { "basename": "jgrd5003.pdf", "url": "https://authors.library.caltech.edu/records/68beq-v2359/files/jgrd5003.pdf" }, "resource_type": "article", "pub_year": "1997", "author_list": "Yung, Yuk L.; Lee, Anthony Y. T.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/2cwbg-h2938", "eprint_id": 48674, "eprint_status": "archive", "datestamp": "2023-08-22 11:40:11", "lastmod": "2023-10-17 19:31:43", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Cagaeo-R-P", "name": { "family": "Cageao", "given": "R. P." } }, { "id": "Ha-Y-L", "name": { "family": "Ha", "given": "Y. L." } }, { "id": "Jiang-Yibo", "name": { "family": "Jiang", "given": "Y." }, "orcid": "0000-0001-6711-7260" }, { "id": "Morgan-M-F", "name": { "family": "Morgan", "given": "M. F." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Y. L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Sander-S-P", "name": { "family": "Sander", "given": "S. P." }, "orcid": "0000-0003-1424-3620" } ] }, "title": "Calculated Hydroxil A^2\u2211 \u2192 X^2\u03a0 (0,0) band emission rate factors applicable to atmospheric spectroscopy", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 1997 Elsevier Science Ltd. Received 26 February 1996; received for publication 3 June 1996. The authors would like to thank Xiaolei Zhu for his efforts in refining the program coding, Drs William Sharp and Randall Friedl for their support, helpful comments, and discussions refining the scope of this paper, and Drs Gary Rottman and Robert Kurucz for illuminating discussions on the solar near ultraviolet spectra. This work was supported by NASA Sounding Rocket Flight Program grant NGR 23-005-36, NASA Graduate Student Researcher's Grant NGT-50010, NASA grant NAGW-2204, a California Institute of Technology Summer Undergraduate Researcher Fund grant and President's Fund grant, and a Jet Propulsion Laboratory Director's Discretionary Fund grant.", "abstract": "A calculation of the A^2\u2211 \u2192 X^2\u03a0 (0, 0) band emission rate factors and line center absorption cross sections of OH applicable to its measurement using solar resonant fluorescence in the terrestrial atmosphere is presented in this paper. The most accurate available line parameters have been used. Special consideration has been given to the solar input flux because of its highly structured Fraunhofer spectrum. The calculation for the OH atmospheric emission rate factor in the solar resonant fluorescent case is described in detail with examples and intermediate results. Results of this calculation of OH emission rate factors for individual rotational lines are, on average, 30% lower than the values obtained in an earlier work.", "date": "1997-05", "date_type": "published", "publication": "Journal of Quantitative Spectroscopy and Radiative Transfer", "volume": "57", "number": "5", "publisher": "Elsevier", "pagerange": "703-717", "id_number": "CaltechAUTHORS:20140819-091518312", "issn": "0022-4073", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140819-091518312", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NGR 23-005-36" }, { "agency": "NASA", "grant_number": "NGT-50010" }, { "agency": "NASA", "grant_number": "NAGW-2204" }, { "agency": "Caltech Summer Undergraduate Research Fellowship (SURF)" }, { "agency": "Caltech President's Fund" }, { "agency": "JPL Director's Discretionary Fund" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/S0022-4073(96)00105-7", "resource_type": "article", "pub_year": "1997", "author_list": "Cageao, R. P.; Ha, Y. L.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/y4ew2-x9m93", "eprint_id": 48678, "eprint_status": "archive", "datestamp": "2023-08-22 11:33:13", "lastmod": "2023-10-17 19:32:01", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Shieh-Ying-Tzung", "name": { "family": "Shieh", "given": "Ying-Tzung" } }, { "id": "Wang-Chung-Ho", "name": { "family": "Wang", "given": "Chung-Ho" } }, { "id": "Chen-Min-Pen", "name": { "family": "Chen", "given": "Min-Pen" } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk-Ling" }, "orcid": "0000-0002-4263-2562" } ] }, "title": "The Last Glacial Maximum to Holocene environment changes in the southern Okinawa Trough", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 1997 Elsevier Science Ltd. Received 2 May 1996, Accepted 8 October 1996, Available online 10 August 2005. The authors arc grateful to J. K. Huang, Y. C. Tseng and S. L. Chen for their assistance with the laboratory work. One of them (Y.-T.S.) thanks S. J. Crowhurst at the Godwin Laboratory. University of Cambridge, for helpful discussions, and Prof. N. J. Shackleton who provided an opportunity lo write the paper at the Godwin Laboratory, University of Cambridge. This research is supported by the National Science Council of the Republic of China, under NSC 80-0209-M002a-005 and NSC 81-0209-M002a-21.", "abstract": "Presented here are the oxygen and carbon isotope records of two epipelagic planktonic foraminiferal species, Globigerinoides sacculifer and Neogloboquadrina dutertrei, from a sediment core which was collected from the southern Okinawa Trough. These isotope records provide an opportunity to understand the paleoceanographic evolution of the Okinawa Trough since the last deglaciation. The Younger Dryas cooling event in the Okinawa Trough is reported for the first time in this paper. These data also record meltwater spikes during the Younger Dryas interval and the entry of the Kuroshio Current into the Okinawa Trough. The oxygen isotope sequence also records the warm and/or humid climate conditions around east Asia at about 5.6 ka and the evolution of the Kuroshio Current during the late Holocene.", "date": "1997-02", "date_type": "published", "publication": "Journal of Asian Earth Sciences", "volume": "15", "number": "1", "publisher": "Elsevier", "pagerange": "3-8", "id_number": "CaltechAUTHORS:20140819-094932289", "issn": "1367-9120", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140819-094932289", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "National Science Council of the Republic of China", "grant_number": "NSC 80-0209-M002a-005" }, { "agency": "National Science Council of the Republic of China", "grant_number": "NSC 81-0209-M002a-21" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/S0743-9547(96)00075-X", "resource_type": "article", "pub_year": "1997", "author_list": "Shieh, Ying-Tzung; Wang, Chung-Ho; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/dmh6k-mb218", "eprint_id": 48667, "eprint_status": "archive", "datestamp": "2023-08-22 11:30:35", "lastmod": "2023-10-17 19:31:19", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Li-Lung-An", "name": { "family": "Li", "given": "Lung-An" } }, { "id": "Wang-Chung-Ho", "name": { "family": "Wang", "given": "Chung-Ho" } }, { "id": "Lia-Shuh-Haung", "name": { "family": "Liaw", "given": "Shuh-Haung" } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk Ling" }, "orcid": "0000-0002-4263-2562" }, { "id": "Li-Yuan-Hui", "name": { "family": "Li", "given": "Yuan-Hui" } }, { "id": "Chen-Yi-Chieh", "name": { "family": "Chen", "given": "Yi-Chieh" } }, { "id": "Li-Piin-Ching", "name": { "family": "Li", "given": "Piin-Ching" } } ] }, "title": "The impact of worldwide volcanic activities on local precipitation; Taiwan as an example", "ispublished": "pub", "full_text_status": "restricted", "keywords": "volcanic activities, ENSO phenomenon, Taiwan precipitation,\nstatistical analysis", "note": "\u00a9 1997 American Geosciences Institute. This work has been partially supported by the funding of the National Science Council of\nTaiwan and the Environmental Sciences Research of Academia Sinica, Taipei, Taiwan.", "abstract": "Sulfur-rich volcanic activities are believed to disturb the\nhydrological cycles in addition to the anomalous temperature\nchanges in the atmosphere. Two statistical analyses are performed\nto evaluate their impact on precipitation, which is determined by\naveraging the records from eight weather stations in Taiwan from\n1897 to 1993. One analysis utilizes the so-called El Nino-Southern\nOscillation (ENSO) phenomenon as a co-factor, while the other does\nnot. It is very note-worthy that both analyses show a statistically\nsignificant drought effect on this local region's precipitation as\nbrought on by such sulfur-rich volcanic activities. The timing of the\noccurrence of these volcanic events are highly correlated with the\ndrought periods in Taiwan, and the magnitudes of their influence\nare found to be two to ten times greater than those by the ENSO.", "date": "1997-01", "date_type": "published", "publication": "Journal of the Geological Society of China", "volume": "40", "number": "1", "publisher": "Geological Society of China; Taipei", "pagerange": "299-311", "id_number": "CaltechAUTHORS:20140819-084348211", "issn": "1018-7057", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140819-084348211", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "National Science Council (Taipei)" }, { "agency": "Academia Sinica" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "resource_type": "article", "pub_year": "1997", "author_list": "Li, Lung-An; Wang, Chung-Ho; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/tqfrq-2qj97", "eprint_id": 52791, "eprint_status": "archive", "datestamp": "2023-08-22 11:24:42", "lastmod": "2023-10-18 21:35:29", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Johnson-R-E", "name": { "family": "Johnson", "given": "R. E." } }, { "id": "Liu-Michael-C", "name": { "family": "Liu", "given": "M." }, "orcid": "0000-0003-2232-7664" }, { "id": "Kass-D-M", "name": { "family": "Kass", "given": "D. M." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Y. L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "The loss of atmosphere from Mars - Response", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 1996 American Association for the Advancement of Science.\n\nReceived 29 May 1996; accepted 14 August 1996.", "abstract": "The results presented in our report\n(1) indicated that it was necessary to\nconsider dissociation during all collisions in\ncalculating the atmospheric loss from Mars\nthat results from sputtering. With the use of\nthe newly calculated cross sections presented\nby Johnson and Liu in our model, we\nfind that Mars has lost about 1 bar of CO_2.\nThe revised cross sections reduce our sputtering\nyields (Table 1), but do not bring our\nresults into agreement with Luhmann et al.\n(2) and Jakosky et al. (3).", "date": "1996-12-13", "date_type": "published", "publication": "Science", "volume": "274", "number": "5294", "publisher": "American Association for the Advancement of Science", "pagerange": "1932-1933", "id_number": "CaltechAUTHORS:20141212-151313513", "issn": "0036-8075", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20141212-151313513", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1126/science.274.5294.1932a", "resource_type": "article", "pub_year": "1996", "author_list": "Johnson, R. E.; Liu, M.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/9e019-7bt22", "eprint_id": 48669, "eprint_status": "archive", "datestamp": "2023-08-22 11:10:59", "lastmod": "2023-10-17 19:31:27", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Moyer-E-J", "name": { "family": "Moyer", "given": "Elisabeth J." } }, { "id": "Irion-F-W", "name": { "family": "Irion", "given": "Fredrick W." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Gunson-M-R", "name": { "family": "Gunson", "given": "Michael R." } } ] }, "title": "ATMOS stratospheric deuterated water and implications for troposphere-stratosphere transport", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1996 American Geophysical Union.\n\nReceived November 3, 1995; revised January 23, 1996; accepted April 4, 1996.\n\nWe thank Michael Brown for his comments and suggestions on this manuscript, and David Keith and Nilton Renno for useful discussions. EJM acknowledges the support of a National Science Foundation Graduate Fellowship and a NASA Global Change Graduate Fellowship. This research was supported in part by NASA grant NAGW-413 to the California Institute of Technology.\n\nPublished - grl9357.pdf
", "abstract": "Measurements of the isotopic composition of stratospheric water by the ATMOS instrument are used to infer the convective history of stratospheric air. The average water vapor entering the stratosphere is found to be highly depleted of deuterium, with \u03b4D_w of \u2212670\u00b180 (67% deuterium loss). Model calculations predict, however, that under conditions of thermodynamic equilibrium, dehydration to stratospheric mixing ratios should produce stronger depletion to \u03b4D_w of \u2212800 to \u2212900 (80\u201390% deuterium loss). Deuterium enrichment of water vapor in ascending parcels can occur only in conditions of rapid convection; enrichments persisting into the stratosphere require that those conditions continue to near-tropopause altitudes. We conclude that either the predominant source of water vapor to the uppermost troposphere is enriched convective water, most likely evaporated cloud ice, or troposphere-stratosphere transport occurs closely associated with tropical deep convection.", "date": "1996-08-15", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "23", "number": "17", "publisher": "American Geophysical Union", "pagerange": "2385-2388", "id_number": "CaltechAUTHORS:20140819-085221671", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140819-085221671", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF Graduate Fellowship" }, { "agency": "NASA Global Change Graduate Fellowship" }, { "agency": "NASA", "grant_number": "NAGW-413" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/96GL01489", "primary_object": { "basename": "grl9357.pdf", "url": "https://authors.library.caltech.edu/records/9e019-7bt22/files/grl9357.pdf" }, "resource_type": "article", "pub_year": "1996", "author_list": "Moyer, Elisabeth J.; Irion, Fredrick W.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/wy3ey-dnq97", "eprint_id": 48660, "eprint_status": "archive", "datestamp": "2023-08-22 11:10:49", "lastmod": "2023-10-17 19:31:02", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Irion-F-W", "name": { "family": "Irion", "given": "F. W." } }, { "id": "Gunson-M-R", "name": { "family": "Gunson", "given": "M. R." } }, { "id": "Rinsland-C-P", "name": { "family": "Rinsland", "given": "C. P." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Y. L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Abrams-M-C", "name": { "family": "Abrams", "given": "M. C." } }, { "id": "Chang-A-Y", "name": { "family": "Chang", "given": "A. Y." } }, { "id": "Goldman-A", "name": { "family": "Goldman", "given": "A." } } ] }, "title": "Heavy ozone enrichments from ATMOS infrared solar spectra", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1996 by the American Geophysical Union.\n\nWe thank L. R. Brown, W. B. DeMore, J. Closs, C.\nB. Farmer, J. C. Foster, P. L. Houston, H. Pickett, I. S. McDermid and G. C. Toon for their assistance. The research reported herein was performed at the Jet Propulsion Laboratory, California Institute of Technology under contract to National Aeronautics and Space Administration.\n\nPublished - grl9399.pdf
", "abstract": "Vertical enrichment profiles of stratospheric ^(16)O^(16)O^(18)O and ^(16)O^(18)O^(16)O (hereafter referred to as ^(668)O_3 and ^(686)O_3 respectively) have been derived from space-based solar occultation spectra recorded at 0.01 cm^(\u22121) resolution by the ATMOS (Atmospheric Trace MOlecule Spectroscopy) Fourier-transform infrared (FTIR) spectrometer. The observations, made during the Spacelab 3 and ATLAS-1, -2, and -3 shuttle missions, cover polar, mid-latitude and tropical regions between 26 to 2.6 mb inclusive (\u2248 25 to 41 km). Average enrichments, weighted by molecular ^(48)O_3 density, of (15\u00b16)% were found for ^(668)O_3 and (10\u00b17)% for ^(686)O_3. Defining the mixing ratio of ^(50)O_3 as the sum of those for ^(668)O_3 and ^(686)O_3, an enrichment of (13\u00b15)% was found for ^(50)O_3 (1\u03c3 standard deviation). No latitudinal or vertical gradients were found outside this standard deviation. From a series of ground-based measurements by the ATMOS instrument at Table Mountain, California (34.4\u00b0N), an average total column ^(668)O_3 enrichment of (17\u00b14)% (1\u03c3 standard deviation) was determined, with no significant seasonal variation discernable. Possible biases in the spectral intensities that affect the determination of absolute enrichments are discussed.", "date": "1996-08-15", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "23", "number": "17", "publisher": "American Geophysical Union", "pagerange": "2377-2380", "id_number": "CaltechAUTHORS:20140818-132914828", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140818-132914828", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "JPL/Caltech/NASA" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/96GL01695", "primary_object": { "basename": "grl9399.pdf", "url": "https://authors.library.caltech.edu/records/wy3ey-dnq97/files/grl9399.pdf" }, "resource_type": "article", "pub_year": "1996", "author_list": "Irion, F. W.; Gunson, M. R.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/8vjmb-w6d58", "eprint_id": 48681, "eprint_status": "archive", "datestamp": "2023-08-22 11:11:04", "lastmod": "2023-10-17 19:32:16", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Irion-F-W", "name": { "family": "Irion", "given": "F. W." } }, { "id": "Moyer-E-J", "name": { "family": "Moyer", "given": "E. J." } }, { "id": "Gunson-M-R", "name": { "family": "Gunson", "given": "M. R." } }, { "id": "Rinsland-C-P", "name": { "family": "Rinsland", "given": "C. P." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Y. L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Michelsen-H-A", "name": { "family": "Michelsen", "given": "H. A." } }, { "id": "Salawitch-R-J", "name": { "family": "Salawitch", "given": "R. J." } }, { "id": "Chang-A-Y", "name": { "family": "Chang", "given": "A. Y." } }, { "id": "Newchurch-M-J", "name": { "family": "Newchurch", "given": "M. J." } }, { "id": "Abbas-M-M", "name": { "family": "Abbas", "given": "M. M." } }, { "id": "Abrams-M-C", "name": { "family": "Abrams", "given": "M. C." } }, { "id": "Zander-R", "name": { "family": "Zander", "given": "R." } } ] }, "title": "Stratospheric observations of CH_3D and HDO from ATMOS infrared solar spectra: Enrichments of deuterium in methane and implications for HD", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1996 by the American Geophysical Union. Received November 3, 1995; revised April 3, 1996; accepted April 12, 1996. Paper number 96GL01402. We thank L. R. Brown, T. L. Brown, J. C. Foster, C.\nB. Farmer, G. D. Lynch, O. F. Raper, and G. C. Toon for their assistance. Research was performed at the Jet Propulsion Laboratory, California Institute of Technology, under contract to the National Aeronautics and Space Administration.\n\nPublished - grl9317.pdf
", "abstract": "Stratospheric mixing ratios of CH_3D from 100 mb to 17 mb (\u2248 15 to 28 km) and HDO from 100 mb to 10 mb (\u2248 15 to 32 km) have been inferred from high resolution solar occultation infrared spectra from the Atmospheric Trace MOlecule Spectroscopy (ATMOS) Fourier-transform interferometer. The spectra, taken on board the Space Shuttle during the Spacelab 3 and ATLAS-1, -2, and -3 missions, extend in latitude from 70\u00b0S to 65\u00b0N. We find CH_3D entering the stratosphere at an average mixing ratio of (9.9\u00b10.8) \u00d7 10^(\u221210) with a D/H ratio in methane (7.1\u00b17.4)% less than that in Standard Mean Ocean Water (SMOW) (1\u03c3 combined precision and systematic error). In the mid to lower stratosphere, the average lifetime of CH_3D is found to be (1.19\u00b10.02) times that of CH_4, resulting in an increasing D/H ratio in methane as air \"ages\" and the methane mixing ratio decreases. We find an average of (1.0\u00b10.1) molecules of stratospheric HDO are produced for each CH_3D destroyed (1\u03c3 combined precision and systematic error), indicating that the rate of HDO production is approximately equal to the rate of CH_3D destruction. Assuming negligible amounts of deuterium in species other than HDO, CH_3D and HD, this limits the possible change in the stratospheric HD mixing ratio below about 10 mb to be \u00b10.1 molecules HD created per molecule CH_3D destroyed.", "date": "1996-08-15", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "23", "number": "17", "publisher": "American Geophysical Union", "pagerange": "2381-2384", "id_number": "CaltechAUTHORS:20140819-102612806", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140819-102612806", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA/JPL/Caltech" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/96GL01402", "primary_object": { "basename": "grl9317.pdf", "url": "https://authors.library.caltech.edu/records/8vjmb-w6d58/files/grl9317.pdf" }, "resource_type": "article", "pub_year": "1996", "author_list": "Irion, F. W.; Moyer, E. J.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/3baq3-0j195", "eprint_id": 48662, "eprint_status": "archive", "datestamp": "2023-08-22 11:10:55", "lastmod": "2023-10-17 19:31:08", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Gunson-M-R", "name": { "family": "Gunson", "given": "M. R." } }, { "id": "Abbas-M-M", "name": { "family": "Abbas", "given": "M. M." } }, { "id": "Abrams-M-C", "name": { "family": "Abrams", "given": "M. C." } }, { "id": "Allen-M-A", "name": { "family": "Allen", "given": "M." } }, { "id": "Brown-L-R", "name": { "family": "Brown", "given": "L. R." } }, { "id": "Brown-T-L", "name": { "family": "Brown", "given": "T. L." } }, { "id": "Chang-A-Y", "name": { "family": "Chang", "given": "A. Y." } }, { "id": "Goldman-A", "name": { "family": "Goldman", "given": "A." } }, { "id": "Irion-F-W", "name": { "family": "Irion", "given": "F. W." } }, { "id": "Lowes-L-L", "name": { "family": "Lowes", "given": "L. L." } }, { "id": "Mahieu-E", "name": { "family": "Mahieu", "given": "E." } }, { "id": "Manney-G-L", "name": { "family": "Manney", "given": "G. L." } }, { "id": "Michelsen-H-A", "name": { "family": "Michelsen", "given": "H. A." } }, { "id": "Newchurch-M-J", "name": { "family": "Newchurch", "given": "M. J." } }, { "id": "Rinsland-C-P", "name": { "family": "Rinsland", "given": "C. P." } }, { "id": "Salawitch-R-J", "name": { "family": "Salawitch", "given": "R. J." } }, { "id": "Stiller-G-P", "name": { "family": "Stiller", "given": "G. P." } }, { "id": "Toon-G-C", "name": { "family": "Toon", "given": "G. C." }, "orcid": "0000-0003-4174-7541" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Y. L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Zander-R", "name": { "family": "Zander", "given": "R." } } ] }, "title": "The Atmospheric Trace Molecule Spectroscopy (ATMOS) experiment: Deployment on the ATLAS Space Shuttle missions", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1996 American Geophysical Union.\n\nReceived April 3, 1996; revised April 25, 1996; accepted May 2, 1996.\n\nThis work was carried out at the Jet Propulsion\nLaboratory, California Institute of Technology, under contract to the National Aeronautics and Space Administration. The authors wish to thank them any people who have contributed their time and effort to the success of ATMOS including Reinhard Beer, Barney Farmer, Julie Foster, Greg Goodson, Gindi Lynch, Bert McKenna, Fred O'Callaghan, Odell Raper, Rudy Schindler, Bhaswar Sen to name but a few.\n\nPublished - grl9364.pdf
", "abstract": "The ATMOS Fourier transform spectrometer was flown for a fourth time on the Space Shuttle as part of the ATLAS-3 instrument payload in November 1994. More than 190 sunrise and sunset occultation events provided measurements of more than 30 atmospheric trace gases at latitudes 3\u201349\u00b0N and 65\u201372\u00b0S, including observations both inside and outside the Antarctic polar vortex. The instrument configuration, data retrieval methodology, and mission background are described to place in context analyses of ATMOS data presented in this issue.", "date": "1996-08-15", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "23", "number": "17", "publisher": "American Geophysical Union", "pagerange": "2333-2336", "id_number": "CaltechAUTHORS:20140818-133030712", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140818-133030712", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/96GL01569", "primary_object": { "basename": "grl9364.pdf", "url": "https://authors.library.caltech.edu/records/3baq3-0j195/files/grl9364.pdf" }, "resource_type": "article", "pub_year": "1996", "author_list": "Gunson, M. R.; Abbas, M. M.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/gwn9r-wyj83", "eprint_id": 48654, "eprint_status": "archive", "datestamp": "2023-08-22 11:07:50", "lastmod": "2023-10-17 19:30:44", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Jaegl\u00e9-L", "name": { "family": "Jaegl\u00e9", "given": "Lyatt" } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Toon-G-C", "name": { "family": "Toon", "given": "Geoffrey C." }, "orcid": "0000-0003-4174-7541" }, { "id": "Sen-B", "name": { "family": "Sen", "given": "Bhaswar" } }, { "id": "Blavier-J-F-L", "name": { "family": "Blavier", "given": "Jean-Fran\u00e7ois L." } } ] }, "title": "Balloon observations of organic and inorganic chlorine in the stratosphere: The role of HClO_4 production on sulfate aerosol", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1996 American Geophysical Union.\n\nReceived January 4, 1996; revised April 15, 1996; accepted April 30, 1996.\n\nThe authors would like to thank S. Sander, C. Webster, R. Martin, J. Francisco, and S. Martin for helpful discussions,\nX. Tie for providing his 2-D model output, and R. Stachnik for making his data available before publication. Part of the research described in this paper was carried out by the Jet Propulsion Laboratory, California Institute of Technology, under contract with the National Aeronautics and\nSpace Administration(NASA). This research is also supported in part by NASA grant NAGW-413 to the California Institute of Technology.\n\nPublished - grl9360.pdf
", "abstract": "Simultaneous observations of stratospheric organic and inorganic chlorine were made in September 1993 out of Fort Sumner, New Mexico, using the JPL balloon-borne MkIV interferometer. Between 15 and 20 km, a significant fraction (20\u201360%) of the inorganic chlorine could not be accounted for by the sum of measured HCl, ClONO_2, and HOCl. Laboratory measurements of the reaction of ClO radicals on sulfuric acid solutions have indicated that, along with HCl, small amounts of perchloric acid, HClO_4, were formed. Very little is known about the fate of HClO_4 in the stratosphere and we use a photochemical box model to determine the impact of this new species on the partitioning of inorganic chlorine in the stratosphere. Assuming that HClO_4 is photochemically stable, it is shown that in the enhanced aerosol loading conditions resulting from Mt. Pinatubo's eruption, HClO_4 could represent a significant reservoir of chlorine in the lower stratosphere, sequestering up to 0.2 ppbv (or 50%) of the total inorganic chlorine at 16 km. The occurrence of this new species could bring to closure the inorganic chlorine budget deficiency made apparent by recent ER-2 aircraft in situ measurements of HCl.", "date": "1996-07-01", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "23", "number": "14", "publisher": "American Geophysical Union", "pagerange": "1749-1752", "id_number": "CaltechAUTHORS:20140818-112821288", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140818-112821288", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NAGW-413" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/96GL01543", "primary_object": { "basename": "grl9360.pdf", "url": "https://authors.library.caltech.edu/records/gwn9r-wyj83/files/grl9360.pdf" }, "resource_type": "article", "pub_year": "1996", "author_list": "Jaegl\u00e9, Lyatt; Yung, Yuk L.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/3h60b-1dj08", "eprint_id": 48673, "eprint_status": "archive", "datestamp": "2023-08-22 11:01:59", "lastmod": "2023-10-17 19:31:40", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Jiang-Yibo", "name": { "family": "Jiang", "given": "Yibo" }, "orcid": "0000-0001-6711-7260" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Concentrations of Tropospheric Ozone from 1979 to 1992 over Tropical Pacific South America from TOMS Data", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 1996 American Association for the Advancement of Science.\n\n25 January 1996; accepted 19 March 1996.\n\nWe thank R. S. Stolarski for sharing his insights into the TOMS data and M. Allen, W. M. Hao, A. Ingersoll, J.-H. Kim, R. Salawitch, S. Sander, J. Logan, H. B. Singh, M. 0. Andreae, and two anonymous referees for valuable comments. We thank the Goddard Ozone Processing Team for use of their data before publication. Supported by NASA grant NAG1 -1806 and National Science Foundation grant ATM 9526209 to the California Institute of Technology. Contribution 5644 from the Division of Geological and Planetary Sciences, California Institute of Technology.", "abstract": "An estimate of tropospheric ozone concentrations was obtained from the difference in the Total Ozone Mapping Spectrometer (TOMS) data between the high Andes and the Pacific Ocean. From 1979 to 1992 the tropospheric ozone concentration apparently increased by 1.48 \u00b1 0.40 percent per year or 0.21 \u00b1 0.06 Dobson unit per year over South America and the surrounding oceans. An increase in biomass burning in the Southern Hemisphere can account for this trend in tropospheric ozone concentrations.", "date": "1996-05-03", "date_type": "published", "publication": "Science", "volume": "272", "number": "5262", "publisher": "American Association for the Advancement of Science", "pagerange": "714-716", "id_number": "CaltechAUTHORS:20140819-090131928", "issn": "0036-8075", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140819-090131928", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NAG1 -1806" }, { "agency": "NSF", "grant_number": "ATM 9526209" } ] }, "other_numbering_system": { "items": [ { "id": "5644", "name": "Caltech Division of Geological and Planetary Sciences" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1126/science.272.5262.714", "resource_type": "article", "pub_year": "1996", "author_list": "Jiang, Yibo and Yung, Yuk L." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/afs3v-0zj86", "eprint_id": 48665, "eprint_status": "archive", "datestamp": "2023-08-22 10:59:46", "lastmod": "2023-10-17 19:31:13", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Jiang-Yibo", "name": { "family": "Jiang", "given": "Yibo" }, "orcid": "0000-0001-6711-7260" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "\u00adYuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Zurek-R-W", "name": { "family": "Zurek", "given": "Richard W." } } ] }, "title": "Decadal evolution of the Antarctic ozone hole", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1986 by the American Geophysical Union. \n\nReceived January 24, 1995; revised December 13, 1995; accepted December 13, 1995. \n\nWe would like to express our appreciation to R. S. Stolarski for sharing his insights of the TOMS data with us. The\nNMC geopotential height and temperature stratospheric analyses were obtained from the National Center for Atmospheric Research as part of an EOS interdisciplinary \nscience investigation; wind and PV fields were derived and provided by Gloria Manney at JPL. We thank M. Allen, L. Froidevaux, R. Herman, L. Jaegle, R. Salawitch, S. Sander,\nand three anonymous referees for valuable comments. This work was supported principally by NASA grant NAGW 2204 to the California Institute of Technology and was carried out there and at JPL, under contract with NASA. Contribution number 5465 from the Division of Geological and Planetary \nSciences, California Institute of Technology.\n\nAccepted Version - jgrd4155.pdf
", "abstract": "Ozone column amounts obtained by the total ozone mapping spectrometer (TOMS) in the southern polar region are analyzed during late austral winter and spring (days 240\u2013300) for 1980\u20131991 using area-mapping techniques and area-weighted vortex averages. The vortex here is defined using the \u221250 PVU (1 PVU = 1.0 \u00d7 10^(\u22126) K kg^(\u22121) m^2 s^(\u22121)) contour on the 500 K isentropic surface. The principal results are: (1) there is a distinct change after 1985 in the vortex-averaged column ozone depletion rate during September and October, the period of maximum ozone loss, and (2) the vortex-averaged column ozone in late August (day 240) has dropped by 70 Dobson units (DU) in a decade due to the loss in the dark and the dilution effect. The mean ozone depletion rate in the vortex between day 240 and the day of minimum vortex-averaged ozone is about 1 DU d^(\u22121) at the beginning of the decade, increasing to about 1.8 DU d^(\u22121) by 1985, and then apparently saturating thereafter. The vortex-average column ozone during September and October has declined at the rate of 11.3 DU yr^(\u22121) (3.8%) from 1980 to 1987 (90 DU over 8 years) and at a smaller rate of 2 DU yr^(\u22121) (0.9%) from 1987 to 1991 (10 DU over 5 years, excluding the anomalous year 1988). We interpret the year-to-year trend in the ozone depletion rate during the earlier part of the decade as due to the rise of anthropogenic chlorine in the atmosphere. The slower trend at the end of the decade indicates saturation of ozone depletion in the vortex interior, in that chlorine amounts in the mid-1980s were already sufficiently high to deplete most of the ozone in air within the isolated regions of the lower-stratospheric polar vortex. In subsequent years, increases in stratospheric chlorine may have enhanced wintertime chemical loss of ozone in the south polar vortex even before major losses during the Antarctic spring.", "date": "1996-04-20", "date_type": "published", "publication": "Journal of Geophysical Research D", "volume": "101", "number": "D4", "publisher": "American Geophysical Union", "pagerange": "8985-8999", "id_number": "CaltechAUTHORS:20140818-142552835", "issn": "0148-0227", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140818-142552835", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NAGW 2204" }, { "agency": "NASA/JPL/Caltech" } ] }, "other_numbering_system": { "items": [ { "id": "5465", "name": "Caltech Division of Geological and Planetary Sciences" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/96JD00063", "primary_object": { "basename": "jgrd4155.pdf", "url": "https://authors.library.caltech.edu/records/afs3v-0zj86/files/jgrd4155.pdf" }, "resource_type": "article", "pub_year": "1996", "author_list": "Jiang, Yibo; Yung, \u00adYuk L.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/7mdaj-pz342", "eprint_id": 48670, "eprint_status": "archive", "datestamp": "2023-08-22 10:54:22", "lastmod": "2023-10-17 19:31:29", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Anbar-A-D", "name": { "family": "Anbar", "given": "A. D." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Y. L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Chavez-F-P", "name": { "family": "Chavez", "given": "F. P." } } ] }, "title": "Methyl bromide: Ocean sources, ocean sinks, and climate sensitivity", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1996 American Geophysical Union.\n\nReceived November1 6, 1994; revised August 31, 1995; accepted September 5, 1995.\n\nThe authors are grateful to J. Butler and J. Lobeft for providing CH_(3)Br and temperature data in electronic format, and for many helpful comments. Thanks to G. Feldman and S. Pazen for providing CZCS data and Pacific oceanographic data, respectively, in electronic format. D. Halpern's suggestions in the early stages of this project are appreciated, as are those of A. Meinrat and an anonymous reviewer. This research was supported by NASA grant NAGW-413 and NOAA grant NA46GP0069. Division of Geological Sciences, California Institute of Technology, contribution 5539.\n\nPublished - gbc328.pdf
", "abstract": "The oceans play an important role in the geochemical cycle of methyl bromide (CH_3Br), the major carrier of O_3-destroying bromine to the stratosphere. The quantity of CH_3Br produced annually in seawater is comparable to the amount entering the atmosphere each year from natural and anthropogenic sources. The production mechanism is unknown but may be biological. Most of this CH_3Br is consumed in situ by hydrolysis or reaction with chloride. The size of the fraction which escapes to the atmosphere is poorly constrained; measurements in seawater and the atmosphere have been used to justify both a large oceanic CH_3Br flux to the atmosphere and a small net ocean sink. Since the consumption reactions are extremely temperature-sensitive, small temperature variations have large effects on the CH_3Br concentration in seawater, and therefore on the exchange between the atmosphere and the ocean. The net CH_3Br flux is also sensitive to variations in the rate of CH_3Br production. We have quantified these effects using a simple steady state mass balance model. When CH_3Br production rates are linearly scaled with seawater chlorophyll content, this model reproduces the latitudinal variations in marine CH_3Br concentrations observed in the east Pacific Ocean by Singh et al. [1983] and by Lobert et al. [1995]. The apparent correlation of CH_3Br production with primary production explains the discrepancies between the two observational studies, strengthening recent suggestions that the open ocean is a small net sink for atmospheric CH_3Br, rather than a large net source. The Southern Ocean is implicated as a possible large net source of CH_3Br to the atmosphere. Since our model indicates that both the direction and magnitude of CH_3Br exchange between the atmosphere and ocean are extremely sensitive to temperature and marine productivity, and since the rate of CH_3Br production in the oceans is comparable to the rate at which this compound is introduced to the atmosphere, even small perturbations to temperature or productivity can modify atmospheric CH_3Br. Therefore atmospheric CH_3Br should be sensitive to climate conditions. Our modeling indicates that climate-induced CH_3Br variations can be larger than those resulting from small (\u00b125%) changes in the anthropogenic source, assuming that this source comprises less than half of all inputs. Future measurements of marine CH_3Br, temperature, and primary production should be combined with such models to determine the relationship between marine biological activity and CH_3Br production. Better understanding of the biological term is especially important to assess the importance of non anthropogenic sources to stratospheric ozone loss and the sensitivity of these sources to global climate change.", "date": "1996-03", "date_type": "published", "publication": "Global Biogeochemical Cycles", "volume": "10", "number": "1", "publisher": "American Geophysical Union", "pagerange": "1", "id_number": "CaltechAUTHORS:20140819-085329885", "issn": "0886-6236", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140819-085329885", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NAGW-413" }, { "agency": "NOAA", "grant_number": "NA46GP006" } ] }, "other_numbering_system": { "items": [ { "id": "5539", "name": "Caltech Division of Geological and Planetary Sciences" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/95GB02743", "primary_object": { "basename": "gbc328.pdf", "url": "https://authors.library.caltech.edu/records/7mdaj-pz342/files/gbc328.pdf" }, "resource_type": "article", "pub_year": "1996", "author_list": "Anbar, A. D.; Yung, Y. L.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/83vgq-75828", "eprint_id": 48680, "eprint_status": "archive", "datestamp": "2023-08-22 10:52:30", "lastmod": "2023-10-17 19:32:11", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Lee-Typhoon", "name": { "family": "Lee", "given": "Typhoon" } }, { "id": "Wang-Chung-Ho", "name": { "family": "Wang", "given": "Chung-Ho" } }, { "id": "Shieh-Ying-Tzung", "name": { "family": "Shieh", "given": "Ying-Tzung" } } ] }, "title": "Dust: A Diagnostic of the Hydrologic Cycle During the Last Glacial Maximum", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 1996 American Association for the Advancement of Science. 17 August 1995; accepted 1 November 1995. Supported in part by NASA grant NAGW 2204 to the California Institute of Technology and by NSC 84-2111-M-001-027GP from the National Science Council of the Republic of China. Y.L.Y. thanks the\nInstitute of Earth Sciences and Academia Sinica for their hospitality during his sabbatical year and A. Ingersoll, L. Jaegle, C. Leovy, D. Rind, and I. Tegen for helpful discussions.", "abstract": "Dust concentrations in ice of the last glacial maximum (LGM) are high in ice cores from Greenland and Antarctica. The magnitude of the enhancements can be explained if the\nstrength of the hydrologic cycle during the LGM was about half of that at present. This notion is consistent with a large decrease (5\u00baC) in ocean temperature during the LGM, as\nrecently deduced from measurements of strontium and calcium in corals.", "date": "1996-02-16", "date_type": "published", "publication": "Science", "volume": "271", "number": "5251", "publisher": "American Association for the Advancement of Science", "pagerange": "962-963", "id_number": "CaltechAUTHORS:20140819-101453548", "issn": "0036-8075", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140819-101453548", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NAGW 2204" }, { "agency": "National Science Council of the Republic of China", "grant_number": "NSC 84-2111-M-001-027GP" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1126/science.271.5251.962", "resource_type": "article", "pub_year": "1996", "author_list": "Yung, Yuk L.; Lee, Typhoon; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/ey3t2-8a327", "eprint_id": 48659, "eprint_status": "archive", "datestamp": "2023-08-22 10:49:24", "lastmod": "2023-10-17 19:30:59", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Tsitas-S-R", "name": { "family": "Tsitas", "given": "Steven R." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "The effect of volcanic aerosols on ultraviolet radiation in Antarctica", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1996 American Geophysical Union.\n\nReceived April 24, 1995; revised September 2, 1995; accepted November 2, 1995.\n\nThis research was supported by grants from the National Aeronautics and Space Administration, through grant number NAGW-413, and the Environmental Protection Agency, through grant number CR818670-01-0.\n\nPublished - grl8905.pdf
", "abstract": "Volcanic eruptions can inject large amounts of aerosol into the atmosphere, and, at large solar zenith angles, scattering by these aerosols can actually increase the flux of UV-B (290\u2013320 nm) radiation reaching the surface. This is surprising since aerosols increase the reflection of sunlight to space. As previous explanations of this phenomenon are heuristic and incomplete, we first provide a rigorous and complete explanation of how this surprising effect occurs. This phenomenon makes Antarctica during spring the most susceptible place on Earth to the scattering effect of volcanic aerosols, due to the combined effect of the spring ozone hole and the large solar zenith angles characteristic of this time of year. We show that an aerosol layer lying above Antarctica during spring will decrease the integrated daily dose of biologically weighted irradiance, weighted by the erythema action spectrum, by only up to 5%. Hence the effects of any significant destruction of ozone induced by volcanic aerosols will not be offset by aerosol scattering. Thus after a volcanic eruption, life in Antarctica during spring will suffer the combined effects of the spring ozone hole and ozone destruction induced by volcanic aerosols, with the latter effect only slightly offset by aerosol scattering.", "date": "1996-01-15", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "23", "number": "2", "publisher": "American Geophysical Union", "pagerange": "157-160", "id_number": "CaltechAUTHORS:20140818-132810133", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140818-132810133", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NAGW-413" }, { "agency": "Environmental Protection Agency (EPA)", "grant_number": "CR818670-01-0" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/95GL03592", "primary_object": { "basename": "grl8905.pdf", "url": "https://authors.library.caltech.edu/records/ey3t2-8a327/files/grl8905.pdf" }, "resource_type": "article", "pub_year": "1996", "author_list": "Tsitas, Steven R. and Yung, Yuk L." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/pgstf-51z91", "eprint_id": 48005, "eprint_status": "archive", "datestamp": "2023-08-22 10:48:00", "lastmod": "2023-10-26 21:28:08", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Gladstone-G-R", "name": { "family": "Gladstone", "given": "G. Randall" } }, { "id": "Allen-M-A", "name": { "family": "Allen", "given": "Mark" } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Y. L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Hydrocarbon Photochemistry in the Upper Atmosphere of Jupiter", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 1996 by Academic Press, Inc. Received April 19, 1995; revised August 29, 1995. We thank J. Moses for many valuable discussions and R. Yelle, L. Stief, and J. Friedson for helpful comments. The support of NASA Grant NAGW-1509 to the California Institute of Technology is gratefully acknowledged.", "abstract": "The hydrocarbon photochemistry in the upper atmosphere of Jupiter is investigated using a one-dimensional, photochemical-diffusive, and diurnally averaged model. The important chemical cycles and pathways among the major species are outlined and a standard model for the North Equatorial Belt region is examined in detail. It is found that several traditionally dominant chemical pathways among the C and C_2 species are replaced in importance by cycles involving C\u2013C_4 species. The pressure and altitude profiles of mixing ratios for several observable hydrocarbon species are compared with available ultraviolet- and infrared-derived abundances. The results of sensitivity studies on the standard model with respect to variations in eddy diffusion profile, solar flux, atomic hydrogen influx, latitude, temperature, and important chemical reaction rates are presented. Measured and calculated airglow emissions of He at 584 \u00c2 and H at 1216 \u00c2 are also used to provide some constraints on the range of model parameters. The relevance of the model results to the upcoming Galileo mission is briefly discussed. The model is subject to considerable improvement; there is a great need for laboratory measurements of basic reaction rates and photodissociation quantum yields, even for such simple species as methylacetylene and allene. Until such laboratory measurements exist there will be considerable uncertainty in the understanding of the C_3and higher hydrocarbons in the atmospheres of the jovian planets.", "date": "1996-01", "date_type": "published", "publication": "Icarus", "volume": "119", "number": "1", "publisher": "Elsevier", "pagerange": "1-52", "id_number": "CaltechAUTHORS:20140805-142237753", "issn": "0019-1035", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140805-142237753", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NAGW-1509" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1006/icar.1996.0001", "resource_type": "article", "pub_year": "1996", "author_list": "Gladstone, G. Randall; Allen, Mark; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/8jz67-a5428", "eprint_id": 48683, "eprint_status": "archive", "datestamp": "2023-08-22 10:33:46", "lastmod": "2023-10-17 19:32:22", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Leu-M-T", "name": { "family": "Leu", "given": "Ming-Taun" } }, { "id": "Timonen-R-S", "name": { "family": "Timonen", "given": "Raimo S." } }, { "id": "Keyser-L-F", "name": { "family": "Keyser", "given": "Leon F." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Heterogeneous Reactions of HNO_3(g) + NaCl(s) \u2192 HCl(g) + NaNO_3(s) and N_2O_5(g) + NaCl(s) \u2192 ClNO_2(g) + NaNO_3(s)", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 1995 American Chemical Society. Received: February 9, 1995; In Final Form: June 29, 1995. Publication Date: August 1995. The research described in this article was performed at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration. Y.L.Y. acknowledges support of NASA Grant NAGW 2204 to the California Institute of Technology. The authors are grateful to Veronica Bierbaum and Carleton Howard for helpful discussion on the development of CI mass spectrometry, Renyi Zhang for the design of the data acquisition system, and Greg Huey and Michel Rossi for\nsending preprints.", "abstract": "The heterogeneous reactions of HNO_3(g) + NaCl(s) \u2192 HCl(g) + NaNO_3(s) (eq 1) and N_2O_5(g) + NaCl(s) \u2192 ClNO_2(g) + NaNO_3(s) (eq 2) were investigated over the temperature range 223-296 K in a flow-tube reactor coupled to a quadrupole mass spectrometer. Either a chemical ionization mass spectrometer (CIMS) or an electron-impact ionization mass spectrometer (EIMS) was used to provide suitable detection sensitivity and selectivity. In order to mimic atmospheric conditions, partial pressures of HNO_3 and N_2O_5 in the range 6 x 10^(-8) ~ 2 x 10^(-6) Torr were used. Granule sizes and surface roughness of the solid NaCl substrates were determined by using a scanning electron microscope. For dry NaCl substrates, decay rates of HNO_3 were used to obtain y(1) = 0.013 \u00b1 0.004 (lo) at 296 K and >0.008 at 223 K, respectively. The error quoted is the statistical error. After all corrections were made, he overall error, including systematic error, was estimated\nto be about a factor of 2. HC1 was found to be the sole gas-phase product of reaction 1. The mechanism changed from heterogeneous reaction to predominantly physical adsorption when the reactor was cooled from 296 to 223 K. For reaction 2 using dry salts, y(2) was found to be less than 1.0 x 10^(-4) at both 223 and 296 K. The gas-phase reaction product was identified as ClNO_2 in previous studies using an infrared spectrometer. An enhancement in reaction probability was observed if water was not completely removed\nfrom salt surfaces, probably due to the reaction of N_2O_5(g) + H_2O(s) \u2192 2HNO_3(g). Our results are compared\nwith previous literature values obtained using different experimental techniques and conditions. The implications of the present results for the enhancement of the hydrogen chloride column density in the lower stratosphere after the El Chichon volcanic eruption and for the chemistry of HCl and HNO_3 in the marine troposphere are discussed.", "date": "1995-08", "date_type": "published", "publication": "Journal of Physical Chemistry", "volume": "99", "number": "35", "publisher": "American Chemical Society", "pagerange": "13203-13212", "id_number": "CaltechAUTHORS:20140819-110325742", "issn": "0022-3654", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140819-110325742", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA/JPL/Caltech" }, { "agency": "NASA", "grant_number": "NAGW 2204" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1021/j100035a026", "resource_type": "article", "pub_year": "1995", "author_list": "Leu, Ming-Taun; Timonen, Raimo S.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/rptej-pz808", "eprint_id": 48679, "eprint_status": "archive", "datestamp": "2023-08-22 10:26:51", "lastmod": "2023-10-17 19:32:06", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Kass-D-M", "name": { "family": "Kass", "given": "D. M." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Y. L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Loss of Atmosphere from Mars Due to Solar Wind-induced Sputtering", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 1995 American Association for the Advancement of Science. 26 July 1994; accepted 1 November 1994. D.K. was supported by an NSF fellowship. This work was supported in part by National Aeronautics and Space Administration grants NAGW-1538 and NAG2-764. We thank J. G. Luhmann and R. E.\nJohnson for comments and discussions.", "abstract": "Because Mars does not have a strong intrinsic magnetic field, the atmosphere is eroded by interactions with the solar wind. Early solar-system conditions enhanced the sputtering loss. It is calculated that -3 bars of carbon dioxide (CO_2) have been sputtered over the last 3.5 billion years. This significant increase over the previous estimate by Luhmann et al. of ~0.14 bar of CO_2 is the result of the development of a more complete model. The\nmodel also predicts slightly greater loss of water-~80 meters instead of the ~50 meters predicted by Luhmann et al. Because estimates of CO_2 on early Mars range from 0.5 to 5 bars, the 0.14-bar estimate is insignificant but the ~3-bar estimate will have a large effect on our understanding of the planet's evolution.", "date": "1995-05-05", "date_type": "published", "publication": "Science", "volume": "268", "number": "5211", "publisher": "American Association for the Advancement of Science", "pagerange": "697-699", "id_number": "CaltechAUTHORS:20140819-100325737", "issn": "0036-8075", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140819-100325737", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NAGW-1538" }, { "agency": "NASA", "grant_number": "NAG2-764" }, { "agency": "NSF" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1126/science.7732377", "resource_type": "article", "pub_year": "1995", "author_list": "Kass, D. M. and Yung, Y. L." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/d2zgg-dhj15", "eprint_id": 48470, "eprint_status": "archive", "datestamp": "2023-08-22 10:01:59", "lastmod": "2023-10-17 19:22:33", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Nair-H", "name": { "family": "Nair", "given": "Hari" } }, { "id": "Allen-M-A", "name": { "family": "Allen", "given": "Mark" } }, { "id": "Anbar-A-D", "name": { "family": "Anbar", "given": "Ariel D." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Clancy-R-T", "name": { "family": "Clancy", "given": "R. Todd" } } ] }, "title": "A Photochemical Model of the Martian Atmosphere", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 1994 by Academic Press, Inc.\n\nReceived March 14 1994; revised May 31, 1994.\n\nWe express our appreciation to J. L. Fox, who provided us with odd nitrogen production rates. We thank D. M. Hunten and V. A. Krasnopolsky for helpful comments during the review process. This work was supported by NASA Grant NAGW 2204 to the California Institute of Technology.", "abstract": "The factors governing the amounts of CO, O_2, and O_3 in the martian atmosphere are investigated using a minimally constrained, one-dimensional photochemical model. We find that the incorporation of temperature-dependent CO_2 absorption cross sections leads to an enhancement in the water photolysis rate, increasing the abundance of OH radicals to the point where the model CO abundance is smaller than observed. Good agreement between models and observations of CO, O_2, O_3, and the escape flux of atomic hydrogen can be achieved, using only gas-phase chemistry, by varying the recommended rate constants for the reactions CO + OH and OH + HO_2 within their specified uncertainties. Similar revisions have been suggested to resolve discrepancies between models and observations of the terrestrial mesosphere.\nThe oxygen escape flux plays a key role in the oxygen budget on Mars; as inferred from the observed atomic hydrogen escape, it is much larger than recent calculations of the exospheric escape rate for oxygen. Weathering of the surface may account for the imbalance. Quantification of the escape rates of oxygen and hydrogen from Mars is a worthwhile objective for an upcoming martian upper atmospheric mission.\nWe also consider the possibility that HO_x radicals may be catalytically destroyed on dust grains suspended in the atmosphere. Good agreement with the observed CO mixing ratio can be achieved via this mechanism, but the resulting ozone column is much higher than the observed quantity. We feel that there is no need at this time to invoke heterogeneous processes to reconcile models and observations.", "date": "1994-09", "date_type": "published", "publication": "Icarus", "volume": "111", "number": "1", "publisher": "Elsevier", "pagerange": "124-150", "id_number": "CaltechAUTHORS:20140813-082303033", "issn": "0019-1035", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140813-082303033", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NAGW 2204" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1006/icar.1994.1137", "resource_type": "article", "pub_year": "1994", "author_list": "Nair, Hari; Allen, Mark; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/vp4j7-cnz74", "eprint_id": 48483, "eprint_status": "archive", "datestamp": "2023-08-22 09:26:46", "lastmod": "2023-10-17 19:23:14", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Anbar-A-D", "name": { "family": "Anbar", "given": "A. D." } }, { "id": "Leu-M-T", "name": { "family": "Leu", "given": "M.-T." } }, { "id": "Nair-H-A", "name": { "family": "Nair", "given": "H. A." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Y. L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Adsorption of HO_x on Aerosol Surfaces: Implications for the Atmosphere of Mars", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1993 by the American Geophysical Union. Received February 3, 1992; revised November 13, 1992; accepted January 14, 1993.\nPaper number 93JE00132. The authors thank D. Michelangeli for providing aerosol data in electronic format. The assistance \nof M. Allen was greatly appreciated. The comments of two anonymous reviewers were extremely helpful. This research was supported by NASA grant NAGW-2204. Division of Geological Sciences, California Institute of Technology, contribution\n5114.\n\nPublished - jgre250.pdf
", "abstract": "The potential impact of heterogeneous chemistry on the abundance and distribution of HO_x in the atmosphere of Mars has been assessed by combining observational data of dust and ice aerosol distributions with an updated photochemical model. Critical parameters include the altitude distributions of aerosols, and the surface loss coefficients (\u03b3) of HO_2 on dust and ice in the lower atmosphere, and H on ice above 40 km. We find that adsorption of HO_2 on dust (\u03b3HO_2 \u2265 0.01), or ice near 30 km (\u03b3HO_2 \u2265 0.1), can deplete OH abundances in the lower atmosphere by 10% or more. Such depletions approach those obtained by lowering the water vapor abundance by an order of magnitude below the global average observed by Viking (\u2248 25%). Since the oxidation of CO is catalyzed by HO_x in the lower atmosphere via the reaction CO + OH \u2192 CO_2 + H, loss of OH due to adsorption of HO_2 on dust or ice at low altitudes could have a significant effect on the ratio CO : CO_2. The adsorption of H on ice at 50 km (\u03b3_H \u2265 0.01) can result in even larger OH depletions. However, this effect is localized to altitudes > 40 km, where CO oxidation is relatively unimportant. Laboratory data suggest that \u03b3HO_2 \u2248 0.01 is a reasonable estimate for adsorption on dust. Larger values are plausible, but are not strongly supported by experimental evidence. The reactivity of HO_2 on ice is unknown, while \u03b3H on ice appears to be < 0.001. There is a need for measurements of HO_x adsorption on surfaces representative of Martian aerosols at temperatures < 220 K.", "date": "1993-06-25", "date_type": "published", "publication": "Journal of Geophysical Research E", "volume": "98", "number": "E6", "publisher": "American Geophysical Union", "pagerange": "10933-10940", "id_number": "CaltechAUTHORS:20140813-090119166", "issn": "0148-0227", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140813-090119166", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NAGW-2204" } ] }, "other_numbering_system": { "items": [ { "id": "5114", "name": "Caltech Division of Geological Sciences" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/93JE00132", "primary_object": { "basename": "jgre250.pdf", "url": "https://authors.library.caltech.edu/records/vp4j7-cnz74/files/jgre250.pdf" }, "resource_type": "article", "pub_year": "1993", "author_list": "Anbar, A. D.; Leu, M.-T.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/nv9tb-n8r70", "eprint_id": 48482, "eprint_status": "archive", "datestamp": "2023-08-22 09:14:04", "lastmod": "2023-10-17 19:23:12", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Gurwell-M-A", "name": { "family": "Gurwell", "given": "Mark A." }, "orcid": "0000-0003-0685-3621" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Fractionation of hydrogen and deuterium on Venus due to collisional ejection", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 1993 Elsevier.\n\nReceived 10 August 1992 ; Accepted 9 September 1992.\n\nWe thank J. Rodriguez for helpful discussions. This work was supported by NASA grant NAG2-764 to the California Institute of Technology.", "abstract": "The fractionation factor \u222b is important for interpreting the current escape fluxes of H and D on Venus and how the D/H ratio has evolved. The escape flux is currently governed by the two processes of charge exchange and collisional ejection by fast oxygen atoms. Using a best-fit parameterized equation for the O-H scattering angle phase function, more accurate branching ratios for the oxygen ion dissociation and including the effects of the initial energy and momentum of the ions and electrons, as well as for the hydrogen and deuterium gas, we have reanalyzed the collisional ejection process. Our analysis produces improved values for the efficiency of H and D escape as a function of the ionospheric temperature. From our results we propose the reduction of the hydrogen flux for collisional ejection from 8 to 3.5 \u00d7 10^6 cm^(\u22122) s^(\u22121). Assuming that collisions leading to escape occur mostly in the region between 200 and 400 km, the revised D/H fractionation factor due to collisional ejection is 0.47, where previously the process had been considered completely discriminating against deuterium escape (or \u222b \u223c 0). The resulting deuterium flux is 3.1 \u00d7 10^4 cm^(\u22122) s^(\u22121), roughly 6 times the flux due to charge exchange, making collisional ejection the dominant escape mechanism for deuterium on Venus.", "date": "1993-02", "date_type": "published", "publication": "Planetary and Space Science", "volume": "41", "number": "2", "publisher": "Elsevier", "pagerange": "91-104", "id_number": "CaltechAUTHORS:20140813-085455448", "issn": "0032-0633", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140813-085455448", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NAG2-764" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/0032-0633(93)90037-3", "resource_type": "article", "pub_year": "1993", "author_list": "Gurwell, Mark A. and Yung, Yuk L." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/gj5kh-3rb22", "eprint_id": 48415, "eprint_status": "archive", "datestamp": "2023-08-22 09:06:29", "lastmod": "2023-10-17 18:47:46", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Allen-M-A", "name": { "family": "Allen", "given": "Mark" } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Gladstone-G-R", "name": { "family": "Gladstone", "given": "G. Randall" } } ] }, "title": "The relative abundance of ethane to acetylene in the Jovian stratosphere", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 1992 by Academic Press, Inc.\n\nReceived January 28, 1991; revised July 27, 1992.\n\nWe thank W. Maguire for communicating the results of the analysis\nof the Voyager IRIS spectra prior to publication and the anonymous\nreferees for their helpful comments. This work was supported by NASA\nGrant NAGW 1509 to the California Institute of Technology. Contribution\nnumber 4852 from The Division of Geological and Planetary Sciences,\nCalifornia Institute of Technology.", "abstract": "The observed ratio of C_2H_6 to C_2H_2 in the Jovian stratosphere increases from \u223c55 at 2 mbar to \u223c277 at 12 mbar. In current photochemical models this ratio typically increases between 2 and 12 mbar by a factor of \u22643. Recent laboratory kinetics studies on the reaction between C_2H_2 and H_2 to form C_2H_4 suggest an efficient chemical mechanism for hydrogenation of C_2H_2 to C_2H_6. Inclusion of this scheme as part of a comprehensive updated model for hydrocarbon photochemistry in the atmosphere of Jupiter provides an explanation of the altitude variation of the C_2H_6/C_2H_2 ratio. The sensitivity of these results to uncertainties in the key rate constants at low temperatures is illustrated, identifying needs for additional laboratory measurements. Since the key reaction rate constants decrease with decreasing temperature, the hydrogenation of C_2H_2 as proposed predicts a qualitatively decreasing trend in the C_2H_6/C_2H_2 value with decreasing distance from the Sun. The observed variation between Jupiter and Saturn is consistent with this prediction.", "date": "1992-12", "date_type": "published", "publication": "Icarus", "volume": "100", "number": "2", "publisher": "Elsevier", "pagerange": "527-533", "id_number": "CaltechAUTHORS:20140812-134036776", "issn": "0019-1035", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140812-134036776", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NAGW 1509" } ] }, "other_numbering_system": { "items": [ { "id": "4852", "name": "Caltech Division of Geological and Planetary Sciences" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/0019-1035(92)90115-N", "resource_type": "article", "pub_year": "1992", "author_list": "Allen, Mark; Yung, Yuk L.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/qev03-4qp74", "eprint_id": 48502, "eprint_status": "archive", "datestamp": "2023-08-22 09:01:21", "lastmod": "2023-10-17 19:24:12", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Moses-J-I", "name": { "family": "Moses", "given": "Julianne I." }, "orcid": "0000-0002-8837-0035" }, { "id": "Allen-M-A", "name": { "family": "Allen", "given": "Mark" } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Hydrocarbon Nucleation and Aerosol Formation in Neptune's Atmosphere", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 1992 by Academic Press, Inc. Received January 7, 1992; revised June 8, 1992. Available online 14 October 2002. We thank the two reviewers for their constructive comments and\ncareful evaluations of the manuscript and P. S. Romani and J. E. Allen, Jr., for useful discussions of vapor pressures. This research was supported by NASA Grants NAGW 1509 and NAGW 2362 to the California Institute of Technology. The first author gratefully acknowledges support from the NASA Graduate Student Researchers Program. This paper represents Contribution Number 4995 from the Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, California 91125.", "abstract": "Photodissociation of methane at high altitude levels in Neptune's atmosphere leads to the production of complex hydrocarbon species such as acetylene (C_2H_2), ethane (C_2H_6), methylacetylene (CH_3C_2H), propane (C_3H_8), diacetylene (C_4H_2), and butane (C_4H_8). These gases diffuse to the lower stratosphere where temperatures are low enough to initiate condensation. Particle formation may not occur readily, however, as the vapor species become supersaturated. We present a theoretical analysis of particle formation mechanisms at conditions relevant to Neptune's troposphere and stratosphere and show that hydrocarbon nucleation is very inefficient under Neptunian conditions: saturation ratios much greater than unity are required for aerosol formation by either homogeneous, heterogeneous, or ion-induced nucleation. Homogeneous nucleation will not be important for any of the hydrocarbon species considered; however, both heterogeneous and ion-induced nucleation should be possible on Neptune for most of the above species. The relative effectiveness of heterogeneous and ion-induced nucleation depends on the physical and thermodynamic properties of the particular species, the abundance of the condensable species, the temperature at which the vapor becomes supersaturated, and the number and type of condensation nuclei or ions available. Typical saturation ratios required for observable particle formation rates on Neptune range from \u223c3 for heterogeneous nucleation of methane in the upper troposphere to greater than 1000 for heterogeneous nucleation of methylacetylene, diacetylene, and butane in the lower stratosphere. Thus, methane clouds may form slightly above, and stratospheric hazes far below, their saturation levels. When used in conjunction with the results of detailed models of atmospheric photochemistry, our nucleation models place realistic constraints on the altitude levels at which we expect hydrocarbon hazes or clouds to form on Neptune.", "date": "1992-10", "date_type": "published", "publication": "Icarus", "volume": "99", "number": "2", "publisher": "Elsevier", "pagerange": "318-346", "id_number": "CaltechAUTHORS:20140813-103124038", "issn": "0019-1035", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140813-103124038", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NAGW 1509" }, { "agency": "NASA", "grant_number": "NAGW 2362" }, { "agency": "NASA Graduate Student Research Fellowship" } ] }, "other_numbering_system": { "items": [ { "id": "4995", "name": "Caltech Division of Geological and Planetary Sciences" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/0019-1035(92)90149-2", "resource_type": "article", "pub_year": "1992", "author_list": "Moses, Julianne I.; Allen, Mark; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/1hcx6-zdp37", "eprint_id": 48471, "eprint_status": "archive", "datestamp": "2023-08-22 09:00:03", "lastmod": "2024-01-13 16:07:44", "type": "book_section", "metadata_visibility": "show", "creators": { "items": [ { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Dissly-R-W", "name": { "family": "Dissly", "given": "Richard W." } } ] }, "title": "Deuterium in the Solar System", "ispublished": "unpub", "full_text_status": "restricted", "note": "\u00a9 1992 American Chemical Society.\n\nReceived January 6, 1992.\n\nWe thank Mark Allen, Dave Stevenson and Geoff Blake for critically reading the manuscript, and Bill Langer for drawing our attention to recent developments in deuterium chemistry in the interstellar medium. The research is supported in part by NASA grants NAGW 1509 and NAGW 1538 to the California Institute of Technology. One of us (RWD) acknowledges support of a NASA graduate fellowship.", "abstract": "A survey of the abundances of deuterium in planetary atmospheres and small bodies has been carried out. The observed pattern of D/H ratios in the solar system may be interpreted in terms of a few simple concepts: origin, fractionation, and dilution. There appear to be two distinct reservoirs of hydrogen in the solar nebula: the bulk of hydrogen as H_2, and a smaller amount in ices and organics. The latter reservoir is characterized by a higher D/H ratio than the former, and may be the principal source of hydrogen to the terrestrial planets and small bodies. The evolution of planetary atmospheres over the age of the solar system has resulted in substantial changes in the D/H ratio in the atmospheres of the terrestrial planets. In the giant planets the abundance of D is dominated by the primordial HD, and there has been negligible chemical evolution since formation. Quantitative modeling of the D/H ratio in the solar system remains hampered by the lack of appropriate chemical kinetics data.", "date": "1992-09-08", "date_type": "published", "publisher": "American Chemical Society", "place_of_pub": "Washington, DC", "pagerange": "369-389", "id_number": "CaltechAUTHORS:20140813-083505685", "isbn": "9780841224711", "book_title": "Isotope Effects in Gas-Phase Chemistry", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140813-083505685", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NAGW 1509" }, { "agency": "NASA", "grant_number": "NAGW 1538" }, { "agency": "NASA Graduate Fellowship" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "contributors": { "items": [ { "id": "Kaye-J-A", "name": { "family": "Kaye", "given": "Jack A." } } ] }, "doi": "10.1021/bk-1992-0502.ch023", "resource_type": "book_section", "pub_year": "1992", "author_list": "Yung, Yuk L. and Dissly, Richard W." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/yf2p2-7x453", "eprint_id": 48496, "eprint_status": "archive", "datestamp": "2023-08-22 08:59:00", "lastmod": "2023-10-17 19:23:51", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Friedl-R-R", "name": { "family": "Friedl", "given": "Randall R." } }, { "id": "Sander-S-P", "name": { "family": "Sander", "given": "Stanley P." }, "orcid": "0000-0003-1424-3620" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Chloryl Nitrate: A Novel Product of the OCIO + NO_3 + M Recombination", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 1992 American Chemical Society. Received: May 20, 1992: In Final Form: July 16, 1992. Part of the research described in this report was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under contract to the National Aeronautics and Space Administration. Y.L.Y. was supported by NASA Grant NAGW-413 to the California Institute of Technology.", "abstract": "The products of the reaction of OClO with NO_3 were investigated between 220 and 298 K using a flow reactor and infrared, visible, and ultraviolet analysis. At temperatures below 250 K new infrared and ultraviolet absorption features were observed and assigned to the novel compound chloryl nitrate (O_2ClONO_2). Additionally, ClO and NO_2 were observed as reaction products, indicating the existence of a second reaction channel. O_2ClONO_2 formation predominates at temperatures below 230 K. The reaction rate constant at 220 K is estimated to be on the order of 10^(-14) cm^3 molecule^(-1) s^(-1) in 1-5 Torr of helium. These observations suggest that O_2ClONO_2 may exist in the terrestrial stratosphere.", "date": "1992-09", "date_type": "published", "publication": "Journal of Physical Chemistry", "volume": "96", "number": "19", "publisher": "American Chemical Society", "pagerange": "7490-7493", "id_number": "CaltechAUTHORS:20140813-094930400", "issn": "0022-3654", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140813-094930400", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA/JPL/Caltech" }, { "agency": "NASA", "grant_number": "NAGW-413" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1021/j100198a002", "resource_type": "article", "pub_year": "1992", "author_list": "Friedl, Randall R.; Sander, Stanley P.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/yy0rm-jrw58", "eprint_id": 48495, "eprint_status": "archive", "datestamp": "2023-08-22 08:48:08", "lastmod": "2023-10-17 19:23:44", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Lyons-J-R", "name": { "family": "Lyons", "given": "James R." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Allen-M-A", "name": { "family": "Allen", "given": "Mark" } } ] }, "title": "Solar Control of the Upper Atmosphere of Triton", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 1992 American Association for the Advancement of Science. \n\nReceived 8 November 1991; Accepted 24 February 1992.\n\nWe thank D. Strobel and R. Yelle for helpful\ndiscussion. This work was supported in part by\nNational Aeronautics and Space Administration\ngrants NAGW-1 509 and NAGW-2362 to the California\nInstitute of Technology. Contribution 5054\nfrom the Division of Geological and Planetary\nSciences, California Institute of Technology,\nPasadena, CA 91125.", "abstract": "If the upper atmosphere and ionosphere of Triton are controlled by precipitation of electrons from Neptune's magnetosphere as previously proposed, Triton could have the only ionosphere in the solar system not controlled by solar radiation. However, a new model of Triton's atmosphere, in which only solar radiation is present, predicts a large column of carbon atoms. With an assumed, but reasonable, rate of charge transfer between N_2^+ and C, a peak C^+ abundance results that is close to the peak electron densities measured by Voyager in Triton's ionosphere. These results suggest that Triton's upper atmospheric chemistry may thus be solar-controlled. Measurement of key reaction rate constants, currently unknown or highly uncertain at Triton's low temperatures, would help to clarify the chemical and physical processes occurring in Triton's atmosphere.", "date": "1992-04-10", "date_type": "published", "publication": "Science", "volume": "256", "number": "5054", "publisher": "American Association for the Advancement of Science", "pagerange": "204-206", "id_number": "CaltechAUTHORS:20140813-093857286", "issn": "0036-8075", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140813-093857286", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NAGW-1509" }, { "agency": "NASA", "grant_number": "NAGW-2362" } ] }, "other_numbering_system": { "items": [ { "id": "5054", "name": "Division of Geological and Planetary Sciences" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1126/science.11540928", "resource_type": "article", "pub_year": "1992", "author_list": "Lyons, James R.; Yung, Yuk L.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/38c54-m4s75", "eprint_id": 48504, "eprint_status": "archive", "datestamp": "2023-08-22 08:44:17", "lastmod": "2023-10-17 19:24:19", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Anderson-S-M", "name": { "family": "Anderson", "given": "S. M." } }, { "id": "Morton-J", "name": { "family": "Morton", "given": "J." } }, { "id": "Mauersberger-K", "name": { "family": "Mauersberger", "given": "K." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Y. L." }, "orcid": "0000-0002-4263-2562" }, { "id": "DeMore-W-B", "name": { "family": "DeMore", "given": "W. B." } } ] }, "title": "A study of atom exchange between O_2(^1\u0394) and ozone", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 1992 Elsevier Science Publishers B.V. Received 27 September 1991; in final form 20 November 1991. Available online 7 February 2002. We would like to thank W.T. Rawlins for stimulating discussions regarding oxygen metastable tactics\nand R.W. Carr for loan of the microwave equipment.", "abstract": "It has recently been suggested that isotope exchange between excited bimolecular oxygen and ozone may be partially responsible for the enrichments in stratospheric heavy ozone. To begin evaluating this possibility we have investigated the reaction ^(18)O_2(^1\u0394)+^(16)O_3\u2192(labeled ozone products) using a fast-flow reactor and molecular beam mass spectrometry. No reaction was observed, implying that the rate coefficient must be less than 5 \u00d7 10^(\u221216) cm^3/s molecule at 300 K, roughly two orders of magnitude smaller than is required to account for the atmospheric anomalies.", "date": "1992-02-21", "date_type": "published", "publication": "Chemical Physics Letters", "volume": "189", "number": "6", "publisher": "Elsevier", "pagerange": "581-585", "id_number": "CaltechAUTHORS:20140813-110851287", "issn": "0009-2614", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140813-110851287", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/0009-2614(92)85254-8", "resource_type": "article", "pub_year": "1992", "author_list": "Anderson, S. M.; Morton, J.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/jj7bs-s6134", "eprint_id": 48490, "eprint_status": "archive", "datestamp": "2023-08-22 08:42:42", "lastmod": "2023-10-17 19:23:35", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Michelangeli-D-V", "name": { "family": "Michelangeli", "given": "Diane V." } }, { "id": "Allen-M-A", "name": { "family": "Allen", "given": "Mark" } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Shia-Run-Lie", "name": { "family": "Shia", "given": "Run-Lie" }, "orcid": "0000-0003-1911-3120" }, { "id": "Crisp-D", "name": { "family": "Crisp", "given": "David" }, "orcid": "0000-0002-4573-9998" }, { "id": "Eluszkiewicz-J", "name": { "family": "Eluszkiewicz", "given": "Janusz" } } ] }, "title": "Enhancement of Atmospheric Radiation by an Aerosol Layer", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1992 by the American Geophysical Union. Received November 28, 1989; revised May 8, 1991; accepted may 8, 1991. Paper number 91JD01308. We thank J. Pollack and the anonymous referees for their extremely helpful comments. This research is supported by EPA grant 9D4125NALX to the California\nInstitute of Technology. Contribution number 4685 from the Division of Geological and Planetary Sciences, California\nInstitute of Technology, Pasadena California 91125.\n\nPublished - jgrd2067.pdf
", "abstract": "The presence of a stratospheric haze layer may produce increases in both the actinic flux and the irradiance below this layer. Such haze layers result from the injection of aerosol-forming material into the stratosphere by volcanic eruptions. Simple heuristic arguments show that the increase in flux below the haze layer, relative to a clear sky case, is a consequence of \"photon trapping.\" We explore the magnitude of these flux perturbations, as a function of aerosol properties and illumination conditions, with a new radiative transfer model that can accurately compute fluxes in an inhomogeneous atmosphere with nonconservative scatterers having arbitrary phase function. One calculated consequence of the El Chichon volcanic eruption is an increase in the midday surface actinic flux at 20\u00b0N latitude, summer, by as much as 45% at 2900 \u00c5. This increase in flux in the UV-B wavelength range was caused entirely by aerosol scattering, without any reduction in the overhead ozone column.", "date": "1992-01-20", "date_type": "published", "publication": "Journal of Geophysical Research D", "volume": "97", "number": "D1", "publisher": "American Geophysical Union", "pagerange": "865-874", "id_number": "CaltechAUTHORS:20140813-092742795", "issn": "0148-0227", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140813-092742795", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Environmental Protection Agency (EPA)", "grant_number": "9D4125NALX" } ] }, "other_numbering_system": { "items": [ { "id": "4685", "name": "Caltech Division of Geological and Planetary Sciences" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/91JD01308", "primary_object": { "basename": "jgrd2067.pdf", "url": "https://authors.library.caltech.edu/records/jj7bs-s6134/files/jgrd2067.pdf" }, "resource_type": "article", "pub_year": "1992", "author_list": "Michelangeli, Diane V.; Allen, Mark; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/fwyk9-m8q82", "eprint_id": 48425, "eprint_status": "archive", "datestamp": "2023-08-22 08:03:14", "lastmod": "2023-10-17 19:20:40", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Michelangeli-D-V", "name": { "family": "Michelangeli", "given": "Diane V." } }, { "id": "Allen-M-A", "name": { "family": "Allen", "given": "Mark" } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Heterogeneous reactions with NaCl in the El Chichon volcanic aerosols", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1991 by the American Geophysical Union. Received: August 24, 1990;\nrevised: November 28, 1990; accepted: February 12, 1991. Paper number 91GL00547. We thank M.-T. Leu for valuable discussions and B. Finlayson-Pitts for communication of laboratory results prior to publication. We also are grateful to the anonymous reviewers for pointing out the deficiencies of our initial presentation. This work was supported by NAGW-413 to California Institute of Technology. One of us (DVM) acknowledges support of a NASA NRC Fellowship. Contribution number 4898 from the Division of Geological and Planetary Sciences, California. Institute of Technology, Pasadena, California 91125.\n\nPublished - grl5408.pdf
", "abstract": "Previous investigations of the effects of the 1982 eruption of the El Chichon volcano could not explain all the observations of changes in O_3, HCl, NO and NO_2 simultaneously without proposing unproven chemical reactions. Since reactions between solid NaCl and gaseous ClNO_3 and N_2O_5 rapidly produce photochemically active chlorine species and solid NaNO_3 in laboratory experiments, we suggest that these reactions could have occurred with the NaCl observed to be present in the El Chichon sulfuric acid aerosols. As a consequence, we predict that HCl should increase substantially, while NO_x should decrease, in agreement with the measurements after the eruption. Ozone should only be slightly affected by these reactions. Reactions between solid NaCl and the acids H_2SO_4 and HNO_3 might prove to be important, but we lack sufficient evidence regarding their efficiency and the presence of HNO_3 in the aerosols to be more conclusive.", "date": "1991-04", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "18", "number": "4", "publisher": "American Geophysical Union", "pagerange": "673-676", "id_number": "CaltechAUTHORS:20140812-142036160", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140812-142036160", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NAGW-413" }, { "agency": "NASA NRC Fellowship" } ] }, "other_numbering_system": { "items": [ { "id": "4898", "name": "Caltech Division of Geological and Planetary Sciences" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/91GL00547", "primary_object": { "basename": "grl5408.pdf", "url": "https://authors.library.caltech.edu/records/fwyk9-m8q82/files/grl5408.pdf" }, "resource_type": "article", "pub_year": "1991", "author_list": "Michelangeli, Diane V.; Allen, Mark; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/921hh-x9976", "eprint_id": 48472, "eprint_status": "archive", "datestamp": "2023-08-22 07:59:35", "lastmod": "2023-10-17 19:22:43", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Landry-B", "name": { "family": "Landry", "given": "Bridget" } }, { "id": "Allen-M-A", "name": { "family": "Allen", "given": "Mark" } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Troposphere-Stratosphere Interactions in a One-Dimensional Model of Jovian Photochemistry", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 1991 by Academic Press Inc. Received April 9, 1990: revised September 4. 1990. Available online 14 October 2002. The assistance provided by R. Achterberg. D. Hunten, D. Strobel and M. Summers it gratefully acknowledged. The research was supported by NASA Grant NSG-7376 to the California Institute of Technology.", "abstract": "A simple one-dimensional model of the Jovian atmosphere including the coupling between a rapidly mixed troposphere and a stagnant stratosphere is presented. We treat analytically the case of a chemically unreactive species flowing downward through the stratosphere and troposphere with a constant flux. The calculated concentration profile has a maximum value approximately one atmospheric scale height above the tropopause. The corresponding mixing ratio rapidly decreases in the lower stratosphere. The contrast between the peak stratosphere and tropopause concentrations reflects the variation between the lower stratosphere and upper troposphere eddy diffusion coefficients. Numerical simulations of unreactive CO and C_2H_6, considering high-altitude photochemical sources (yielding downward fluxes to the troposphere) and deep troposphere thermochemical sources, demonstrate that upper troposphere abundances may have a large photochemical contribution Recent observations of CO near 5 bar can be reproduced by a model using any one of three different tropospheric eddy diffusion profiles: a constant value of \u223c 10^8 cm^2 sec^(\u22121), a constant value of \u227e10^4 cm^2 sec^(-1), or a two-layer model with a rapidly mixed (10^8 cm^2 sec^(\u22121)) layer below 20 bar and a slower mixing layer (10^4 cm^2 sec^(\u22121)) between 100 mbar and 20 bar. In the latter two scenarios, the photochemical source is an important and/or dominant source of upper tropospheric CO. However, the upper tropospheric C_2H_6 abundances are distinctly different among the three cases. These calculations suggest objectives for higher spectral resolution observations, critical vertical scales for planning experiments on future missions to Jupiter, and predictions that can be tested with the Galileo probe mass spectrometer.", "date": "1991-02", "date_type": "published", "publication": "Icarus", "volume": "89", "number": "2", "publisher": "Elsevier", "pagerange": "377-383", "id_number": "CaltechAUTHORS:20140813-083803473", "issn": "0019-1035", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140813-083803473", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NSG-7376" } ] }, "other_numbering_system": { "items": [ { "id": "4716", "name": "Caltech Division of Geological and Planetary Sciences" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/0019-1035(91)90184-U", "resource_type": "article", "pub_year": "1991", "author_list": "Landry, Bridget; Allen, Mark; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/swn2w-3vk13", "eprint_id": 48467, "eprint_status": "archive", "datestamp": "2023-08-22 07:56:49", "lastmod": "2023-10-17 19:22:25", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "DeMore-W-B", "name": { "family": "DeMore", "given": "W. B." } }, { "id": "Pinto-J-P", "name": { "family": "Pinto", "given": "Joseph P." } } ] }, "title": "Isotopic exchange between carbon dioxide and ozone via O(^1D) in the stratosphere", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1991 by the American Geophysical Union. Paper number 90GL02478. Received August 6, 1990; revised October 9, 1990; accepted November 5, 1990. We thank M. Allen, S. Epstein,R .\nFriedl, K. Mauersberger, D. Michelangeli, and S. Sanderf or\nuseful discussions, and M. Gunson and M. Thiemens for\nconmunication of results prior to publication. One of us\n(YLY) wishes to thank J.-S. Wen for drawingh is attention to\nthe work of Gamo et al., and sharing with him his experimental insights. This research was supported by NASA\ngrant NAGW-413 to California Institute of Technology and\nEPA grant 9D4 25 NALX to California Institute of Technology,\nand by the Jet Propulsion Laboratory, California Institute\nof Technology under contract with NASA. Contribution\nnumber 4889 from the Division of Geological and Planetary\nSciences, California Institute of Technology, Pasadena,\nCalifornia 91125.\n\nPublished - grl5233.pdf
", "abstract": "We propose a novel mechanism for isotopic exchange between CO_2 and O_3 via O(^1D) + CO_2 \u2192 CO_3^* followed by CO_3^* \u2192 CO_2 + O(^3P). A one-dimensional model calculation shows that this mechanism can account for the enrichment in ^(18)O in the stratospheric CO_2 observed by Gamo et al. [1989], using the heavy O_3 profile observed by Mauersberger [1981]. The implications of this mechanism for other stratospheric species and as a source of isotopically heavy CO_2 in the troposphere are briefly discussed.", "date": "1991-01", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "18", "number": "1", "publisher": "American Geophysical Union", "pagerange": "13-16", "id_number": "CaltechAUTHORS:20140813-072334926", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140813-072334926", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NAGW-413" }, { "agency": "Environmental Protection Agency (EPA)", "grant_number": "9D4 25 NALX" }, { "agency": "NASA/JPL/Caltech" } ] }, "other_numbering_system": { "items": [ { "id": "4889", "name": "Caltech Division of Geological and Planetary Sciences" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/90GL02478", "primary_object": { "basename": "grl5233.pdf", "url": "https://authors.library.caltech.edu/records/swn2w-3vk13/files/grl5233.pdf" }, "resource_type": "article", "pub_year": "1991", "author_list": "Yung, Yuk L.; DeMore, W. B.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/7r1x9-fcq92", "eprint_id": 48468, "eprint_status": "archive", "datestamp": "2023-08-22 07:43:56", "lastmod": "2023-10-17 19:22:27", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Y. L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Lyons-J-R", "name": { "family": "Lyons", "given": "J. R." } } ] }, "title": "Triton: Topside ionosphere and nitrogen escape", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1990 by the American Geophysical Union. Paper number 90GL01465. Received: April 20, 1990; revised: June 12, 1990; accepted: June 25, 1990. We thank M. Summers, D. Strobel, J. Richardson, R. Selesnick, and S. Srivastava for communicating to us their results prior to publication, and M. Allen and S. Trajmar for valuable discussions. This work is supported in part by NASA grant NAGW 1509 to the California Institute of Technology, and by the Jet Propulsion Laboratory, California Institute of Technology under contract with NASA. Contribution number 4860 from the Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, California 91125.\n\nPublished - grl5024.pdf
", "abstract": "The principal ion in the ionosphere of Triton is N^+. Energetic electrons of magnetospheric origin are the primary source of ionization, with a smaller contribution due to photoionization. To explain the topside plasma scale height, we postulate that N^+ ions escape from Triton. The loss rate is 3.4 \u00d7 10^7 cm^(\u22122) s^(\u22121) or 7.9 \u00d7 10^(24) ions s^(\u22121). Dissociative recombination of N^+_2 produces neutral exothermic fragments that can escape from Triton. The rate is estimated to be 8.6 \u00d7 10^6 N cm^(\u22122) s^(\u22121) or 2.0 \u00d7 10^(24) atoms s^(\u22121). Implications for the magnetosphere of Neptune and Triton's evolution are discussed.", "date": "1990-09", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "17", "number": "10", "publisher": "American Geophysical Union", "pagerange": "1717-1720", "id_number": "CaltechAUTHORS:20140813-075114752", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140813-075114752", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NAGW 1509" }, { "agency": "NASA/JPL/Caltech" } ] }, "other_numbering_system": { "items": [ { "id": "4860", "name": "Caltech Division of Geological and Planetary Sciences" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/GL017i010p01717", "primary_object": { "basename": "grl5024.pdf", "url": "https://authors.library.caltech.edu/records/7r1x9-fcq92/files/grl5024.pdf" }, "resource_type": "article", "pub_year": "1990", "author_list": "Yung, Y. L. and Lyons, J. R." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/e2696-j7g28", "eprint_id": 48451, "eprint_status": "archive", "datestamp": "2023-08-22 07:37:28", "lastmod": "2023-10-17 19:21:47", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Shia-Run-Lie", "name": { "family": "Shia", "given": "Run-Lie" }, "orcid": "0000-0003-1911-3120" }, { "id": "Ha-Yuk-Lung", "name": { "family": "Ha", "given": "Yuk Lung" } }, { "id": "Wen-Jun-Shan", "name": { "family": "Wen", "given": "Jun-Shan" } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Two-dimensional atmospheric transport and chemistry model: Numerical experiments with a new advection algorithm", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1990 The American Geophysical Union.\n\nReceived June 6, 1988;\nRevised July 26, 1989;\nAccepted July 26, 1989. \n\nWe are indebted to M. Allen, D. Crisp, and R. Zurek for critical comments on the manuscript. We thank M. Prather for sending us the detailed derivations of his numerical scheme, and D. Stevenson for directing us to find an analytic solution for experiment 4. Special thanks axe due to one of the referees (R. Rood) for suggesting experiment 5 and for insightful comments. This work is supported by NASA grant NAGW-413 to the California Institute of Technology. Y.L.H. acknowledges the support of a Caltech SURF Fellowship in the summer of 1987. After our work had been completed, we learned that Douglass et al. (1989) successfully used Prather's method in their two-dimensional model. Division of Geological and Planetary Sciences, California Institute of Technology, Contribution 4599.\n\nPublished - jgrd1503.pdf
", "abstract": "Extensive testing of the advective scheme, proposed by Prather (1986), has been carried out in support of the California Institute of Technology\u2013Jet Propulsion Laboratory two-dimensional model of the middle atmosphere. We generalize the original scheme to include higher-order moments. In addition, we show how well the scheme works in the presence of chemistry as well as eddy diffusion. Six types of numerical experiments including simple clock motion and pure advection in two dimensions have been investigated in detail. By comparison with analytic solutions it is shown that the new algorithm can faithfully preserve concentration profiles, has essentially no numerical diffusion, and is superior to a typical fourth-order finite difference scheme.", "date": "1990-05-20", "date_type": "published", "publication": "Journal of Geophysical Research D", "volume": "95", "number": "D6", "publisher": "American Geophysical Union", "pagerange": "7467-7483", "id_number": "CaltechAUTHORS:20140812-155205729", "issn": "0148-0227", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140812-155205729", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NAGW-413" }, { "agency": "Caltech SURF Fellowship" } ] }, "other_numbering_system": { "items": [ { "id": "4599", "name": "Division of Geological and Planetary Sciences" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/JD095iD06p07467", "primary_object": { "basename": "jgrd1503.pdf", "url": "https://authors.library.caltech.edu/records/e2696-j7g28/files/jgrd1503.pdf" }, "resource_type": "article", "pub_year": "1990", "author_list": "Shia, Run-Lie; Ha, Yuk Lung; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/qxsma-yqn12", "eprint_id": 48498, "eprint_status": "archive", "datestamp": "2023-08-22 07:37:14", "lastmod": "2023-10-17 19:23:55", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Allen-M-A", "name": { "family": "Allen", "given": "Mark" } }, { "id": "Crisp-D", "name": { "family": "Crisp", "given": "David" }, "orcid": "0000-0002-4573-9998" }, { "id": "Zurek-R-W", "name": { "family": "Zurek", "given": "Richard W." } }, { "id": "Sander-S-P", "name": { "family": "Sander", "given": "Stanley P." }, "orcid": "0000-0003-1424-3620" } ] }, "title": "Spatial Variation of Ozone Depletion Rates in the Springtime Antarctic Polar Vortex", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 1990 American Association for the Advancement of Science.\n24 October 1989; accepted 22 February 1990. We are \ngrateful to R. Stolarski for providing TOMS data before publication and to P. Newman for sending us potential\nvorticity data. We thank K. K. Tung, R. Friedl, J. Rodriguez, M. Schoeberl, and R. L. Shia for illuminating\ndiscussions, S. Solomon for critical comments on systematic errors of TOMS data, and X.-L. Zhu for plotting all the graphs in this report. Part of the research described in this paper was carried out by the Jet Propulsion Laboratory,\nunder contract with the National Aeronautics and Space\nAdministration, and was also supported by NASA grant\nNAGW-413 to the California Institute of Technology. Contribution number 4783 from the Division of Geological\nand Planetary Sciences, California Institute of Technology.", "abstract": "An area-mapping technique, designed to filter out synoptic perturbations of the Antarctic polar vortex such as distortion or displacement away from the pole, was applied to the Nimbus-7 TOMS (Total Ozone Mapping Spectrometer) data. This procedure reveals the detailed morphology of the temporal evolution of column O_3. The results for the austral spring of 1987 suggest the existence of a relatively stable collar region enclosing an interior that is undergoing large variations. There is tentative evidence for quasi-periodic (15 to 20 days) O_3 fluctuations in the collar and for upwelling of tropospheric air in late spring. A simplified photochemical model of O_3 loss and the temporal evolution of the area-mapped polar O_3 are used to constrain the chlorine monoxide (C1O) concentrations in the springtime Antarctic vortex. The\nconcentrations required to account for the observed loss of O_3 are higher than those previously reported by Anderson et al. but are comparable to their recently revised\nvalues. However, the O_3 loss rates could be larger than deduced here because of underestimates of total O_3 by TOMS near the terminator. This uncertainty, together with the uncertainties associated with measurements acquired during the Airborne Antarctic Ozone Experiment, suggests that in early spring, closer to the vortex center, there may be even larger ClO concentrations than have yet been detected.", "date": "1990-05-11", "date_type": "published", "publication": "Science", "volume": "248", "number": "4956", "publisher": "American Association for the Advancement of Science", "pagerange": "721-724", "id_number": "CaltechAUTHORS:20140813-100857739", "issn": "0036-8075", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140813-100857739", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA/JPL" }, { "agency": "NASA", "grant_number": "NAGW-413" } ] }, "other_numbering_system": { "items": [ { "id": "4783", "name": "Caltech Division of Geological and Planetary Sciences" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1126/science.11538181", "resource_type": "article", "pub_year": "1990", "author_list": "Yung, Yuk L.; Allen, Mark; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/68dc7-7b464", "eprint_id": 48469, "eprint_status": "archive", "datestamp": "2023-08-22 07:12:56", "lastmod": "2023-10-17 19:22:29", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Howell-C-D", "name": { "family": "Howell", "given": "Colin D." } }, { "id": "Michelangeli-D-V", "name": { "family": "Michelangeli", "given": "Diane V." } }, { "id": "Allen-M-A", "name": { "family": "Allen", "given": "Mark" } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "SME observations of O_2(^1\u0394_g) nightglow: An assessment of the chemical production mechanisms", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 1990 Pergamon Press. Received 5 October 1989, Available online 11 October 2002. We gratefully acknowledge assistance\nreceived from R. T. Clancy and M. T. Leu. This work was\nsupported by NASA grant NAGW-890 to the University of\nColorado and NASA grant NAGW-413 to the California\nInstitute of Technology. C. D. Howell was supported by a\nCalifornia Institute of Technology Summer Undergraduate\nResearch Fellowship.", "abstract": "Solar Mesosphere Explorer (SME) observations of the 3 a.m. 1.27 \u03bcm nightglow at 45\u00b0N latitude, averaged over the period 10\u201331 July 1984, are reported. From the deduced volume emission rates, we derive the O_2(a^1\u0394_g) night-time production rates for the 80\u2013100 km altitude range. Utilizing the mean SME-acquired 3 p.m. ozone profile for the same latitude and time period and an updated photochemical model, we determine night-time O, O_3, H, OH, HO_2, and H_2O_2 profiles. These are used in calculating the rates of reactions which are sufficiently exothermic to produce O_2(^1\u0394) or excited states of OH or HO_2, which could transfer their energy to O_2 to form O_2(^1\u0394). Of these reactions, most have rates that are quite small compared with the observed night-time O_2(^1\u0394) production rate. For several others, laboratory experiments have found O_2(^1\u0394) yields which are insufficient for simulating the observed O_2(^1\u0394). Using yields of O_2(^1\u0394) based on published laboratory and observational studies, we find that the sum of two reaction sequences can approximate the SME measurements: (1) O + O + M and (2) H + O_3 followed by OH^\u2217 + O_2.", "date": "1990-04", "date_type": "published", "publication": "Planetary and Space Science", "volume": "38", "number": "4", "publisher": "Elsevier", "pagerange": "529-537", "id_number": "CaltechAUTHORS:20140813-080817194", "issn": "0032-0633", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140813-080817194", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NAGW-890" }, { "agency": "NASA", "grant_number": "NAGW-413" }, { "agency": "Caltech Summer Undergraduate Research Fellowship (SURF)" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/0032-0633(90)90145-G", "resource_type": "article", "pub_year": "1990", "author_list": "Howell, Colin D.; Michelangeli, Diane V.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/6yk3m-qat07", "eprint_id": 49945, "eprint_status": "archive", "datestamp": "2023-08-22 07:00:17", "lastmod": "2023-10-17 22:23:42", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Michelangeli-D-V", "name": { "family": "Michelangeli", "given": "Diane V." } }, { "id": "Allen-M-A", "name": { "family": "Allen", "given": "Mark" } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "El Chichon Volcanic Aerosols: Impact of Radiative, Thermal, and Chemical Perturbations", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1989 by the American Geophysical Union. Received September 30, 1988; revised May 30, 1989; accepted May 30, 1989.\n\nPaper number 89JD01149. \n\nThe authors wish to thank T. P. Ackerman and J. B. Pollack for providing the results of their optical calculations.\nCommunications, prior to publication, from W. G. Mankin, B. A. Ridley, M. McFarland, S. Chandra, and T. Clancy are greatly appreciated. This work has also benefited from numerous discussions with M. J. Molina, M. T. Leu, R. R. Friedl, S. P. Sander, and W. B. DeMore. The comments of S. Solomon and anonymous reviewers have helped us improve the manuscript. This research was supported by NASA grant NAGW-413. Division of Geological and Planetary Sciences, California Institute of Technology, contribution 4197.\n\nPublished - jgrd1395.pdf
", "abstract": "We examine the consequences of the eruption of the El Chichon volcano on the Earth's stratospheric chemistry. Formed after the eruption, the volcanic aerosol cloud, with a peak particle density at 27 km, was very efficient at altering the radiation field. The results of a one-dimensional radiative transfer model show that the total radiation increased by 8% within the aerosol layer longward of 3000 \u00c5. At certain altitudes and wavelengths below 3000 \u00c5, the total radiation decreased by 15%. Consequently, there are changes in the photolysis rates obtained with a one-dimensional photochemical model: for example, O_2 photodissociation rate constants decrease by 10%, while O_3 photodissociation rate constants increase by a comparable amount. A combination of this radiation change and the effect of a temperature variation of a few degrees causes the abundance of O_3 to decrease by 7% at 24 km, in good agreement with the Solar Backscattered Ultraviolet experiment (SBUV) measurements of a 5\u201310% decrease. The combined radiative and thermal perturbations on the concentrations of O, O(1D), OH, HO_2, H_2O_2, NO, NO_2, NO_3, N_2O_5, HNO_3, HO_2NO_2, Cl, ClO, ClO_2, HOCl, ClNO_3, and HCl are computed and presented in detail. However, these changes as calculated are insufficient to explain the observations of significant decreases in NO and NO_2 and increases in HCl. A heterogeneous reaction catalyzed by aerosol surfaces which transforms ClNO_3 into HCl provides a pathway for sequestering NO_x, and at the same time reduces ClNO_3 in favor of HCl. The inclusion of this reaction in the model leads to a satisfactory single-step explanation of the otherwise puzzling observations of NO, NO_2, and HCl. The observed lack of change in HNO_3 cannot be explained by this hypothesis. The effects of a number of heterogenous reactions, some believed to be important for the Antarctic stratosphere, have been assessed with our model. We also examine the hypothesis of direct injection of gases from the volcano into the stratosphere. Only an unrealistically large injection (60% column increase above 12 km) results in an HCl increase in agreement with observations. An equally large water injection decreases HCl, and decreases the NO and NO_2 by as much as 20%, but still does not simulate the observed NO_x decrease.", "date": "1989-12-20", "date_type": "published", "publication": "Journal of Geophysical Research D", "volume": "94", "number": "D15", "publisher": "American Geophysical Union", "pagerange": "18429-18443", "id_number": "CaltechAUTHORS:20140923-130500338", "issn": "0148-0227", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140923-130500338", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NAGW-413" } ] }, "other_numbering_system": { "items": [ { "id": "4197", "name": "Caltech Division of Geological and Planetary Sciences" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/JD094iD15p18429", "primary_object": { "basename": "jgrd1395.pdf", "url": "https://authors.library.caltech.edu/records/6yk3m-qat07/files/jgrd1395.pdf" }, "resource_type": "article", "pub_year": "1989", "author_list": "Michelangeli, Diane V.; Allen, Mark; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/jc36x-cw325", "eprint_id": 49946, "eprint_status": "archive", "datestamp": "2023-08-22 07:00:22", "lastmod": "2023-10-17 22:23:44", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Shia-Run-Lie", "name": { "family": "Shia", "given": "Run-Lie" }, "orcid": "0000-0003-1911-3120" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Allen-M-A", "name": { "family": "Allen", "given": "Mark" } }, { "id": "Zurek-R-W", "name": { "family": "Zurek", "given": "Richard W." } }, { "id": "Crisp-D", "name": { "family": "Crisp", "given": "David" }, "orcid": "0000-0002-4573-9998" } ] }, "title": "Sensitivity Study of Advection and Diffusion Coefficients in a Two-Dimensional Stratospheric Model Using Excess Carbon 14 Data", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1989 by the American Geophysical Union. Received December 14, 1988; revised April 19, 1989; accepted April 19, 1989. \n\nPaper number 89JD00796.\n\nWe thank K. K. Tung and H. Yang for sending us the detailed transport coefficients of their two-dimensional model and for many discussions and comments which resulted in a great improvement of this paper. We are indebted to H. S. Johnston and F. S. Rowland for useful discussions. An anonymous referee was helpful in sharpening the conclusions of our paper. This work is supported by NASA grant NAGW-413 to the California Institute of Technology. Contribution 4724 from the Division of Geological and Planetary Sciences, California Institute of Technology.\n\nPublished - jgrd1398.pdf
", "abstract": "Using the California Institute of Technology/Jet Propulsion Laboratory two-dimensional transport model, with transport coefficients taken from Yang and Tung (1989), we study the time evolution of excess carbon 14 in the stratosphere and the troposphere from October 1963 to December 1966. The model provides a satisfactory simulation of the observed data. Due to the impulsive nature of its source, initial distributions of excess carbon 14 exhibit large spatial gradients. This permits important constraints on the range of transport coefficients in the lower stratosphere to be derived. The standard model uses the circulation and eddy diffusivity of the year 1980. Large deviations (by factor of 2) from this standard transport are ruled out by our model. A self-consistently derived K_(yy) which is small (\u223c10^9 cm^2 s^(\u22121)) in tropical regions, but is larger (\u223c10^(10) cm^2 s^(\u22121)) at higher latitudes is preferred. A Kzz as large as 1\u00d710^4 cm^2 s^(\u22121) would be inconsistent with the data. Excess carbon 14 is removed from the atmosphere with surface deposition velocities v_S = 3 \u00d7 10^(\u22123) cm s^(\u22121) and v_N = 5 \u00d7 10^(\u22123) cm s^(\u22121) in the southern and northern hemispheres, respectively. The last result is contrary to the current understanding that the oceans are the dominant sink for excess ^(14)C.", "date": "1989-12-20", "date_type": "published", "publication": "Journal of Geophysical Research D", "volume": "94", "number": "D15", "publisher": "American Geophysical Union", "pagerange": "18467-18484", "id_number": "CaltechAUTHORS:20140923-131901960", "issn": "0148-0227", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140923-131901960", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NAGW-413" } ] }, "other_numbering_system": { "items": [ { "id": "4724", "name": "Caltech Division of Geological and Planetary Sciences" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/JD094iD15p18467", "primary_object": { "basename": "jgrd1398.pdf", "url": "https://authors.library.caltech.edu/records/jc36x-cw325/files/jgrd1398.pdf" }, "resource_type": "article", "pub_year": "1989", "author_list": "Shia, Run-Lie; Yung, Yuk L.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/9bcn8-2z885", "eprint_id": 49358, "eprint_status": "archive", "datestamp": "2023-08-22 06:58:28", "lastmod": "2023-10-17 21:21:04", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Moses-J-I", "name": { "family": "Moses", "given": "Julianne I." }, "orcid": "0000-0002-8837-0035" }, { "id": "Allen-M-A", "name": { "family": "Allen", "given": "Mark" } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Neptune's visual albedo variations over a solar cycle: A pre-Voyager look at ion-induced nucleatlon and cloud formation in Neptune's troposphere", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1989 by the American Geophysical Union.\n\nReceived: July 21, 1989;\nrevised: October 20, 1989;\naccepted: October 20, 1989.\n\nPaper number 89GL03355.\n\nWe thank G. W. Lockwood, J. F.\nAppleby, K. Rages, and D. Crisp for useful discussions.\nThis research was supported in part by NASA grant NAGW\n1509 to California Institute of Technology.\n\nPublished - grl4584.pdf
", "abstract": "High-energy galactic cosmic rays can penetrate to deep levels within Neptune's atmosphere to form a substantial ionospheric layer in the lower stratosphere and upper troposphere of the planet. Because cosmic-ray modulation in the interplanetary medium creates an inverse relationship between cosmic-ray intensity and solar activity, the ionization rate in the lower atmosphere will vary with the 11-year solar cycle in such a way that maximum ionization will occur at sunspot minimum and minimum ionization at sunspot maximum. This variable ionization may, by the process of ion-induced nucleation, regulate the formation and optical properties of an upper tropospheric haze in the atmosphere of Neptune and could thus provide a mechanism for modulating the planet's visual brightness over a solar cycle. We estimate the rates of cosmic-ray ionization at solar maximum and minimum for a range of proposed Neptune dipole magnetic field strengths; discuss the physics of formation of ion clusters and eventual aerosol particles; and, using a simple radiative transfer model, discuss the ways in which this variable aerosol formation can modulate the geometric albedo of Neptune over a solar cycle. If Voyager spacecraft observations reveal that Neptune's dipole magnetic field is about 1 Gauss or less, then our modeling indicates that variations in an aerosol layer due to differences in cosmic ray ionization may help explain some of the observed brightness variation of Neptune over a solar cycle.", "date": "1989-12", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "16", "number": "12", "publisher": "American Geophysical Union", "pagerange": "1489-1492", "id_number": "CaltechAUTHORS:20140908-151426203", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140908-151426203", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NAGW 1509" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/GL016i012p01489", "primary_object": { "basename": "grl4584.pdf", "url": "https://authors.library.caltech.edu/records/9bcn8-2z885/files/grl4584.pdf" }, "resource_type": "article", "pub_year": "1989", "author_list": "Moses, Julianne I.; Allen, Mark; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/z2e4k-p9s77", "eprint_id": 49944, "eprint_status": "archive", "datestamp": "2023-08-22 06:55:02", "lastmod": "2023-10-17 22:23:39", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Wen-Jun-Shan", "name": { "family": "Wen", "given": "Jun-Shan" } }, { "id": "Moses-J-I", "name": { "family": "Moses", "given": "Julianne I." }, "orcid": "0000-0002-8837-0035" }, { "id": "Landry-B-M", "name": { "family": "Landry", "given": "Bridget M." } }, { "id": "Allen-M-A", "name": { "family": "Allen", "given": "Mark" } } ] }, "title": "Hydrogen and Deuterium Loss from the Terrestrial Atmosphere: A Quantitative Assessment of Nonthermal Escape Fluxes", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1989 by the American Geophysical Union. Received June 6, 1988; revised February 10, 1989; accepted February 10, 1989.\n\nPaper number 89JD00307.\n\nWe thank D. Hunten and W. B. Hanson for illuminating discussions. This research was supported by NASA grant NAGW-1538 to the California Institute of Technology.\nContribution number 4575 from the Division of Geological and\nPlanetary Sciences, California Institute of Technology, Pasadena, California.\n\nPublished - jgrd1331.pdf
", "abstract": "A comprehensive one-dimensional photochemical model extending from the middle atmosphere (50 km) to the exobase (432 km) has been used to study the escape of hydrogen and deuterium from the Earth's atmosphere. The model incorporates recent advances in chemical kinetics as well as atmospheric observations by satellites, especially the Atmosphere Explorer C satellite. The results suggest: (1) the escape fluxes of both H and D are limited by the upward transport of total hydrogen and total deuterium at the homopause (this result is known as Hunten's limiting flux theorem); (2) about one fourth of total hydrogen escape is thermal, the rest being nonthermal; (3) escape of D is nonthermal; and (4) charge exchange and polar wind are important mechanisms for the nonthermal escape of H and D, but other nonthermal mechanisms may be required. The efficiency to escape from the terrestrial atmosphere for D is 0.74 of the efficiency for H. If the difference between the D/H ratio measured in deep-sea tholeiite glass and that of standard sea water, \u03b4D = \u221277\u2030, were caused by the escape of H and D, we estimate that as much water as the equivalent of 36% of the present ocean might have been lost in the past.", "date": "1989-10-20", "date_type": "published", "publication": "Journal of Geophysical Research D", "volume": "94", "number": "D12", "publisher": "American Geophysical Union", "pagerange": "14971-14989", "id_number": "CaltechAUTHORS:20140923-125432831", "issn": "0148-0227", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140923-125432831", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NAGW-1538" } ] }, "other_numbering_system": { "items": [ { "id": "4575", "name": "Caltech Division of Geological and Planetary Sciences" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/JD094iD12p14971", "primary_object": { "basename": "jgrd1331.pdf", "url": "https://authors.library.caltech.edu/records/z2e4k-p9s77/files/jgrd1331.pdf" }, "resource_type": "article", "pub_year": "1989", "author_list": "Yung, Yuk L.; Wen, Jun-Shan; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/d8zdz-79430", "eprint_id": 49943, "eprint_status": "archive", "datestamp": "2023-08-22 06:54:57", "lastmod": "2023-10-17 22:23:37", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Wen-J-S", "name": { "family": "Wen", "given": "Jun-Shan" } }, { "id": "Pinto-J-P", "name": { "family": "Pinto", "given": "Joseph P." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Photochemistry of CO and H_2O: Analysis of Laboratory Experiments and Applications to the Prebiotic Earth's Atmosphere", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1989 by the American Geophysical Union. Received June 6, 1988; revised February 14, 1989; accepted February 14, 1989. \n\nPaper number 89JD00342. \n\nThis work was partially supported by NASA grant NAGW-1538 to the California Institute of Technology. We thank H. D. Holland for many long and productive discussions and for exerting a benign influence on us over the years. We thank J. F. Kasting and K. J. Zahnle for many stimulating discussions. We also thank two referees for their constructive and useful comments. Contribution number 4570 from the Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena.\n\nPublished - jgrd1330.pdf
", "abstract": "The role photochemical reactions in the early Earth's atmosphere played in the prebiotic synthesis of simple organic molecules was examined. We have extended an earlier calculation of formaldehyde production rates to more reduced carbon species, such as methanol, methane, and acetaldehyde. We have simulated the experimental results of Bar-Nun and Chang (1983) as an aid in the construction of our photochemical scheme and as a way of validating our model. Our results indicate that some fraction of CO_2 and H_2 present in the primitive atmosphere could have been converted to simple organic molecules. The exact amount is dependent on the partial pressure of CO_2 and H_2 in the atmosphere and on what assumptions are made concerning the shape of the absorption spectra of CO_2 and H_2O. In particular, the results are most sensitive to the presence or absence of absorption at wavelengths longward of 2000 \u00c5. We also find that small quantities of CH_4 could have been present in the prebiotic Earth's atmosphere as the result of the photoreduction of CO.", "date": "1989-10-20", "date_type": "published", "publication": "Journal of Geophysical Research D", "volume": "94", "number": "D12", "publisher": "American Geophysical Union", "pagerange": "14957-14970", "id_number": "CaltechAUTHORS:20140923-123908672", "issn": "0148-0227", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140923-123908672", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NAGW-1538" } ] }, "other_numbering_system": { "items": [ { "id": "4570", "name": "Caltech Division of Geological and Planetary Sciences" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/JD094iD12p14957", "primary_object": { "basename": "jgrd1330.pdf", "url": "https://authors.library.caltech.edu/records/d8zdz-79430/files/jgrd1330.pdf" }, "resource_type": "article", "pub_year": "1989", "author_list": "Wen, Jun-Shan; Pinto, Joseph P.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/hfan3-0f682", "eprint_id": 49270, "eprint_status": "archive", "datestamp": "2023-08-22 06:50:57", "lastmod": "2023-10-17 21:15:54", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Sander-S-P", "name": { "family": "Sander", "given": "Stanley P." }, "orcid": "0000-0003-1424-3620" }, { "id": "Friedl-R-R", "name": { "family": "Friedl", "given": "Randall R." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Rate of Formation of the ClO Dimer in the Polar Stratosphere: Implications for Ozone Loss", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 1989 American Association for the Advancement of Science.\n\nReceived 29 March 1989; accepted 12 July 1989.\n\nPart of the research described in this report was\ncarried out by the Jet Propulsion Laboratory, California\nInstitute of Technology, under contract with\nthe National Aeronautics and Space Administration\n(NASA). Y.L.Y. was supported by NASA grant\nNAGW-413 to the California Institute of Technology.\nWe acknowledge several valuable conversations\nwith M. Allen, W. DeMore, C. B. Farmer, J.\nMargitan, M. Molina, J. Rodriguez, G. Toon, and J.\nSander. We thank D. Hofmann, R. DeZafra, R.\nSchindler, C. B. Farmer, C. Howard, D. McKenna,\nand D. Hartmann for preprints.", "abstract": "The gas-phase recombination of chlorine monoxide (ClO) has been investigated under the conditions of pressure and temperature that prevail in the Antarctic stratosphere during the period of maximum ozone (O_3) disappearance. Measured rate constants are less than one-half as great as the previously accepted values. One-dimensional model calculations based on the new rate data indicate that currently accepted chemical mechanisms can quantitatively account for the observed O_3 losses in late spring (17 September to 7 October). A qualitative assessment indicates that the existing mechanisms can only account for at most one-half of the measured O3 depletion in the early spring (28 August to 17 September), indicating that there may be additional catalytic cycles, besides those currently recognized, that destroy O_3.", "date": "1989-09-08", "date_type": "published", "publication": "Science", "volume": "245", "number": "4922", "publisher": "American Association for the Advancement of Science", "pagerange": "1095-1098", "id_number": "CaltechAUTHORS:20140905-090620093", "issn": "0036-8075", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140905-090620093", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NAGW-413" }, { "agency": "NASA/JPL/Caltech" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1126/science.245.4922.1095", "resource_type": "article", "pub_year": "1989", "author_list": "Sander, Stanley P.; Friedl, Randall R.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/f15b7-aen05", "eprint_id": 49637, "eprint_status": "archive", "datestamp": "2023-09-15 04:50:40", "lastmod": "2023-10-23 21:10:38", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Summers-M-E", "name": { "family": "Summers", "given": "M. E." } }, { "id": "Strobel-D-F", "name": { "family": "Strobel", "given": "D. F." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Y. L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Trauger-J-T", "name": { "family": "Trauger", "given": "J. T." } }, { "id": "Mills-F-P", "name": { "family": "Mills", "given": "F." } } ] }, "title": "The structure of Io's thermal corona and implications for atmospheric escape", "ispublished": "pub", "full_text_status": "public", "keywords": "planets: magnetospheres - planets: satellites", "note": "\u00a9 1989 American Astronomical Society.\n\nProvided by the NASA Astrophysics Data System.\n\nReceived 1986 August 14; accepted 1989 January 5.\n\nThe authors thank W. H. Smyth, N. Schneider, E. Sittler,\nand G. Ballester for useful discussions on this topic. This work\nwas supported by the National Aeronautics and Space Administration,\ncontract NAGW-648 and the Voyager Mission.\n\nPublished - 1989ApJ___343__468S.pdf
", "abstract": "We investigate the escape of species from Io's atmosphere using a steady-state model of Io's exospheric\ncorona and its interaction with the Io plasma torus. The corona is assumed to be spherically symmetric with\nthe radial density and compositional structure determined by the gas kinetic temperature, critical level radius,\nand mixing ratios of the component species. Thermal and nonthermal escape rates are calculated and the\nresults compared with previously estimated torus and neutral cloud supply rates for O, S, Na, and K. Both\noxygen- and sulfur-dominated exospheres are considered. Atmospheric sputtering is found to be the major\nescape mechanism for models in which the plasma flow reaches the critical level. However, such models\nproduce total mass-loading rates an order of magnitude larger than inferred values suggesting that either (1)\nthe structure of the thermal corona is significantly modified by the nonthermal interaction, or (2) substantial\nplasma flow modification and deflection occurs in the corona at or above the critical level. Assuming that the\nthermal model is a correct description of the corona, a comparison of these results with the observed near-Io\ndistribution of neutral Na and estimated source rates for the neutral Na \"jets\" suggests an extended Na\ncoronal component. Assuming that this component is part of the thermal exosphere, we find that the observations\nare consistent with an O-dominated corona, an exospheric temperature ~1000 K, a 0.001 critical level\nmixing ratio of Na, and a critical level radius ~1.5 R_(Io).", "date": "1989-08-01", "date_type": "published", "publication": "Astrophysical Journal", "volume": "343", "number": "1", "publisher": "American Astronomical Society", "pagerange": "468-480", "id_number": "CaltechAUTHORS:20140912-084209603", "issn": "0004-637X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140912-084209603", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NAGW-648" }, { "agency": "NASA Voyager Mission" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1086/167720", "primary_object": { "basename": "1989ApJ___343__468S.pdf", "url": "https://authors.library.caltech.edu/records/f15b7-aen05/files/1989ApJ___343__468S.pdf" }, "resource_type": "article", "pub_year": "1989", "author_list": "Summers, M. E.; Strobel, D. F.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/rt0wm-j7q85", "eprint_id": 48372, "eprint_status": "archive", "datestamp": "2023-08-22 06:01:35", "lastmod": "2023-10-17 18:45:35", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Wen-J-S", "name": { "family": "Wen", "given": "Jun-Shan" } }, { "id": "Pinto-J-P", "name": { "family": "Pinto", "given": "Joseph P." } }, { "id": "Allen-M-A", "name": { "family": "Allen", "given": "Mark" } }, { "id": "Pierce-K-K", "name": { "family": "Pierce", "given": "Kathryn K." } }, { "id": "Paulson-S", "name": { "family": "Paulson", "given": "Suzanne" } } ] }, "title": "HDO in the Martian Atmosphere: Implications for the Abundance of Crustal Water", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 1988 Academic Press, Inc.\n\nReceived December 7, 1987; revised February 29, 1988.\n\nWe thank T. Owen for communicating to us observational\nresults prior to publication. One of us (JPP) thanks the Planetary Science Faculty for their hospitality during his visit at the Division of Geological and Planetary Sciences at Caltech. This research was supported by NASA Grants NSG 7376 and NAGW-254 to the California Institute of Technology.", "abstract": "The physical and chemical processes that lead to the preferential escape of hydrogen over deuterium in the Martian atmosphere are studied in detail using a one-dimensional photochemical model. Comparison of our theory with recent observations of HDO suggests that, averaged over the planet, Mars contains 0.2 m of crustal water that is exchangeable with the atmosphere. Our estimate is considerably lower than recent estimates of subsurface water on Mars based on geomorphological analysis of Viking images. The estimate can be reconciled if only a small fraction of crustal water can exchange with the atmosphere.", "date": "1988-10", "date_type": "published", "publication": "Icarus", "volume": "76", "number": "1", "publisher": "Elsevier", "pagerange": "146-159", "id_number": "CaltechAUTHORS:20140812-085451392", "issn": "0019-1035", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140812-085451392", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NSG-7376" }, { "agency": "NASA", "grant_number": "NAGW-254" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/0019-1035(88)90147-9", "resource_type": "article", "pub_year": "1988", "author_list": "Yung, Yuk L.; Wen, Jun-Shan; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/cdfsn-zxx42", "eprint_id": 49172, "eprint_status": "archive", "datestamp": "2023-08-22 05:45:18", "lastmod": "2023-10-17 21:11:25", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Drew-W-A", "name": { "family": "Drew", "given": "William A." } }, { "id": "Pinto-J-P", "name": { "family": "Pinto", "given": "Joseph P." } }, { "id": "Friedl-R-R", "name": { "family": "Friedl", "given": "Randall R." } } ] }, "title": "Estimation of the Reaction Rate for the Formation of CH_3O from H + H_2CO: Implications for Chemistry in the Solar System", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 1988 by Academic Press, Inc. Received 29 October 1986; revised 13 July 1987. Available online 26 October 2002. We thank M. Allen, W. E. DeMore, L. B. Harding, J. I. Lunine, S. Sander, G. J. Wasserburg, C. W. Westbrook, R. G. Prinn, and B. Fegley, Jr. for helpful discussions. This research was supported by NASA Grants NAGW-254 and NSG 7376 to the California Institute of Technology. JPP and RRF are supported\nby NASA NRC postdoctoral fellowships.", "abstract": "It is argued that the formation of the methoxy radical (CH_3O) from H + H_2CO may play an essential role in the reduction of CO to CH_4. The rate coefficient for this reaction has been estimated using the approximate theory of J. Troe (1977a, J. Chem. Phys. 66, 4745) and transition state theory. We briefly discuss the implications of this reaction for the chemistry of CO on Jupiter, in the solar nebula, for interpreting the laboratory experiments of A. Bar-Nun and A. Shaviv (1975, Icarus 24, 197) and A. Bar-Nun and S. Chang (1983, J. Geophys. Res. 88, 6662) and for organic synthesis in the prebiotic terrestrial atmosphere.", "date": "1988-03", "date_type": "published", "publication": "Icarus", "volume": "73", "number": "3", "publisher": "Elsevier", "pagerange": "516-526", "id_number": "CaltechAUTHORS:20140903-082102685", "issn": "0019-1035", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140903-082102685", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NAGW-254" }, { "agency": "NASA", "grant_number": "NSG 7376" }, { "agency": "NASA NRC postdoctoral fellowships" } ] }, "other_numbering_system": { "items": [ { "id": "4382", "name": "Caltech Division of Geological and Planetary Sciences" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/0019-1035(88)90061-9", "resource_type": "article", "pub_year": "1988", "author_list": "Yung, Yuk L.; Drew, William A.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/t211s-spp39", "eprint_id": 48505, "eprint_status": "archive", "datestamp": "2023-08-22 05:45:02", "lastmod": "2023-10-17 19:24:21", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Friedl-R-R", "name": { "family": "Friedl", "given": "Randall R." } }, { "id": "Pinto-J-P", "name": { "family": "Pinto", "given": "Joseph P." } }, { "id": "Bayes-K-D", "name": { "family": "Bayes", "given": "Kyle D." } }, { "id": "Wen-J-S", "name": { "family": "Wen", "given": "Jun-Shan" } } ] }, "title": "Kinetic isotopic fractionation and the origin of HDO and CH_3D in the solar system", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 1988 Academic Press, Inc.\n\nReceived May 18, 1987; Revised November 15, 1987.\n\nWe acknowledge stimulating discussions with E. M.\nShoemaker, M. Allen, and J. I. Lunine. We thank R. G. Prinn for pointing out the potential importance of starlight as a means for initiating photochemistry in the Solar System. This work was partly inspired by G. J. Wasserburg's grandiose vision of geochemistry and cosmochemistry in our division although there is no conceivable correlation between this humble research and his grandiose vision. Support by NASA Grants NSG 7376 and NAGW 313 of the Planetary Atmospheres Program is gratefully acknowledged. RRF and JPP are supported by NASA NRC fellowships.", "abstract": "It is argued that photochemical processes, driven by ultraviolet starlight, could lead to large deuterium fractionation for H_2O and CH_4 relative to H_2 in the primitive solar nebula. Implications for deuterium enrichment observed in planetary atmospheres are briefly discussed.", "date": "1988-03", "date_type": "published", "publication": "Icarus", "volume": "74", "number": "1", "publisher": "Elsevier", "pagerange": "121-132", "id_number": "CaltechAUTHORS:20140813-111517222", "issn": "0019-1035", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140813-111517222", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NSG-7376" }, { "agency": "NASA", "grant_number": "NAGW-313" }, { "agency": "NASA NRC Fellowship" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/0019-1035(88)90034-6", "resource_type": "article", "pub_year": "1988", "author_list": "Yung, Yuk L.; Friedl, Randall R.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/2x3pr-vsn07", "eprint_id": 49953, "eprint_status": "archive", "datestamp": "2023-08-22 05:34:29", "lastmod": "2023-10-17 22:23:59", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Clarke-J-T", "name": { "family": "Clarke", "given": "John T." } }, { "id": "Hudson-M-K", "name": { "family": "Hudson", "given": "Mary K." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "The excitation of the far ultraviolet electroglow emissions on Uranus, Saturn, and Jupiter", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1987 by the American Geophysical Union. Received March 25, 1987; revised October 5, 1987; accepted October 9, 1987. \n\nPaper number 7A9027.\n\nWe wish to acknowledge helpful discussions with A. Dessler, W.-H. Ip, H. Mayr, J. Moses, D. Shemansky, H. Waite, J. Warren, and R. Yelle. M.K.H. acknowledges support from\nNASA grant NAGW-809 to Dartmouth College, and Y.L.Y. acknowledges support from NASA grant NSG 7376 to the California Institute of Technology. The Editor thanks R. V. Yelle and another referee for their assistance in evaluating this paper.\n\nPublished - jgra8719.pdf
", "abstract": "We propose that the diffuse FUV emissions of H and H_2 in excess of photoelectron excitation observed from the sunlit atmospheres of Uranus, Saturn, and Jupiter are produced by electric field acceleration of photoelectrons and ions locally in the upper atmospheres. This in situ acceleration is required to satisfy the many observational constraints on the altitude distribution, exciting particle energy, and total input energy requirements of the electroglow mechanism. We further suggest that a primary mechanism leading to this acceleration is an ionospheric dynamo, which is created in the same manner as the Earth's dynamo. The calculated altitude of charge separation by the neutral wind drag on ions across magnetic field lines is consistent with the observed peaks in electroglow emissions from the Voyager ultraviolet spectrometer limb scan data on both Saturn (near the homopause) and Uranus (just above the homopause). This dynamo action therefore appears to initiate the acceleration process, which must have the form of field-aligned potentials to accelerate the magnetized electrons. We propose that these field-aligned potentials are due to anomalous resistivity, which results from sufficiently high field-aligned currents in the ionosphere to generate plasma instabilities and therefore runaway electrons and ions above some critical lower initial energy. There are multiple candidate processes for inducing these currents, including polarization in the equivalent F regions and inner magnetospheric convection, and each of these processes should exhibit latitudinal structure. The acceleration of low-energy electrons in an H_2 atmosphere preferentially results in FUV radiation and further ionization, whereas electron acceleration in a nitrogen/oxygen atmosphere such as the Earth' is dominated by elastic scattering and thus results in electric currents. Individual electron and proton collisions with H_2 molecules will result in excitation, ionization, and heating, so that considerable enhancement of the ionospheric density and heating of the upper atmosphere will accompany the FUV emission.", "date": "1987-12-30", "date_type": "published", "publication": "Journal of Geophysical Research A", "volume": "92", "number": "A13", "publisher": "American Geophysical Union", "pagerange": "15139-15147", "id_number": "CaltechAUTHORS:20140923-142045443", "issn": "0148-0227", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140923-142045443", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NAGW-809" }, { "agency": "NASA", "grant_number": "NSG 7376" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/JA092iA13p15139", "primary_object": { "basename": "jgra8719.pdf", "url": "https://authors.library.caltech.edu/records/2x3pr-vsn07/files/jgra8719.pdf" }, "resource_type": "article", "pub_year": "1987", "author_list": "Clarke, John T.; Hudson, Mary K.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/nwxa7-66820", "eprint_id": 45579, "eprint_status": "archive", "datestamp": "2023-08-22 05:32:50", "lastmod": "2023-10-26 18:05:28", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Atmospheres and Ionospheres of the Outer Planets and Their Satellites [Book Review]", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 1987 by Academic Press, Inc.\nBook review of: Atmospheres and Ionospheres of the Outer Planets and Their Satellites. By S. K. Atreya. Springer-Verlag,\nBerlin, 1986. 224 pp., ISBN: 9780387168326.", "abstract": "The Pioneer and Voyager missions to the outer solar\nsystem have resulted in a quantum jump in our knowledge\nof the aeronomy of the Jovian planets and their\nsatellites. There is an urgent need for a monograph\nthat summarizes the extensive data base and provides\nsome interpretation. This little book accomplishes the\nfirst task admirably well, and the second task reasonably\nwell.", "date": "1987-12", "date_type": "published", "publication": "Icarus", "volume": "72", "number": "3", "publisher": "Elsevier", "pagerange": "653-654", "id_number": "CaltechAUTHORS:20140507-140457474", "issn": "0019-1035", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140507-140457474", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/0019-1035(87)90063-7", "resource_type": "article", "pub_year": "1987", "author_list": "Yung, Yuk L." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/j340h-z8v25", "eprint_id": 48370, "eprint_status": "archive", "datestamp": "2023-08-22 05:30:49", "lastmod": "2023-10-17 18:45:26", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "An Update of Nitrile Photochemistry on Titan", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 1987 Academic Press, Inc.\n\nReceived October 28, 1986; revised March 25, 1987.\n\nWe thank M. Allen, K. D. Bayes, W. B. DeMore, H. Okabe, L. F. Phillips, J. P. Pinto, R. E. Samuelson, and L. J. Stief for helpful discussions. We thank two anonymous referees for extremely important comments on the chemical kinetics and polar chemistry. This research was supported by NASA Grants\nNAGW-254 and NAGW-313 to the California Institute of Technology.", "abstract": "New chemical schemes leading to the formation of cyanogen (C_2N_2) and dicyanoacetylene (C_4N_2) in the upper atmosphere of Titan are proposed and examined in light of recent laboratory kinetics experiments and voyager observations.", "date": "1987-11", "date_type": "published", "publication": "Icarus", "volume": "72", "number": "2", "publisher": "Elsevier", "pagerange": "468-472", "id_number": "CaltechAUTHORS:20140812-085251258", "issn": "0019-1035", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140812-085251258", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NAGW-254" }, { "agency": "NASA", "grant_number": "NAGW-313" } ] }, "other_numbering_system": { "items": [ { "id": "4390", "name": "Caltech Division of Geological and Planetary Sciences" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/0019-1035(87)90186-2", "resource_type": "article", "pub_year": "1987", "author_list": "Yung, Yuk L." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/0fstz-jv087", "eprint_id": 49482, "eprint_status": "archive", "datestamp": "2023-08-22 05:31:03", "lastmod": "2023-10-17 21:28:28", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Allen-M-A", "name": { "family": "Allen", "given": "M." } }, { "id": "Delitsky-M", "name": { "family": "Delitsky", "given": "M." } }, { "id": "Huntress-W-T-Jr", "name": { "family": "Huntress", "given": "W." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Y." }, "orcid": "0000-0002-4263-2562" }, { "id": "Ip-Wing-Huen", "name": { "family": "Ip", "given": "W.-H." }, "orcid": "0000-0002-3140-5014" }, { "id": "Schwenn-R", "name": { "family": "Schwenn", "given": "R." } }, { "id": "Rosenbauer-H", "name": { "family": "Rosenbauer", "given": "H." } }, { "id": "Shelley-E", "name": { "family": "Shelley", "given": "E." } }, { "id": "Balsiger-H", "name": { "family": "Balsiger", "given": "H." } }, { "id": "Geiss-J", "name": { "family": "Geiss", "given": "J." } } ] }, "title": "Evidence for methane and ammonia in the coma of comet P/Halley", "ispublished": "pub", "full_text_status": "public", "keywords": "atomic and molecular processes; comets", "note": "\u00a9 1987 European Southern Observatory.\n\nReceived February 10; accepted April 30, 1987.\n\nThis work represents one phase of research carried out at the Jet Propulsion Laboratory, California Institute of Technology, under contract to the National Aeronautics and Space Administration. Partial support also was received from NASA grant NSG-7376 to the California Institute of Technology. The Giotto IMS experiment was supported by the National Aeronautics and Space Administration, the German Bundesministerium f\u00fcr Forschung und Technologie, and the Swiss National Science Foundation.\n\nPublished - 1987A+A___187__502A.pdf
", "abstract": "Methane and ammonia abundances in the coma of Halley are derived from Giotto IMS data using an Eulerian model of chemical and physical processes inside the contact surface to simulate Giotto HIS ion mass spectral data for mass-to-charge ratios (m/q) from 15 to 19. The ratio m/q = 19/18 as a function of distance from the nucleus is not reproduced by a model for a pure water coma. It is necessary to include the presence of NH_3 , and uniquely NH_3 , in coma gases in order to explain the data. A ratio of production rates Q(NH_3)/Q(H20) = 0.01-Q.02 results in model values approximating the Giotto data. Methane is identified as the most probable source of the distinct peak at m/q = 15.\nThe observations are fit best with Q(CH_4)/Q(H_20) = 0.02. The chemical composition of the comet nucleus implied by these production rate ratios is unlike that of the outer planets. On the other hand, there are also significant differences from observations of gas phase interstellar material.", "date": "1987-11", "date_type": "published", "publication": "Astronomy and Astrophysics", "volume": "187", "number": "1-2", "publisher": "EDP Sciences", "pagerange": "502-512", "id_number": "CaltechAUTHORS:20140909-090832242", "issn": "0004-6361", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140909-090832242", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NSG-7376" }, { "agency": "Bundesministerium f\u00fcr Forschung und Technologie (BMFT)" }, { "agency": "Swiss National Science Foundation (SNSF)" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "primary_object": { "basename": "1987A+A___187__502A.pdf", "url": "https://authors.library.caltech.edu/records/0fstz-jv087/files/1987A+A___187__502A.pdf" }, "resource_type": "article", "pub_year": "1987", "author_list": "Allen, M.; Delitsky, M.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/wsap7-ye533", "eprint_id": 49719, "eprint_status": "archive", "datestamp": "2023-08-22 05:26:45", "lastmod": "2023-10-17 22:06:46", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Leu-M-T", "name": { "family": "Leu", "given": "Ming-Taun" } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Determination of O_2 (a\u00b9\u0394g) and O_2 (b\u00b9\u03a3^+g) yields in the reaction O + ClO \u2192 Cl + O_2 : Implications for photochemistry in the atmosphere of Venus", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1987 by the American Geophysical Union. Received April 21, 1987; revised June 11, 1987; accepted July 6, 1987. \n\nPaper number 7L6572. We thank W. A. Traub, W. B. DeMore, M. Allen, J. P. Pinto, L. W. Esposito, D. V. Michelangeli, and L. D. Travis for helpful discussions. This research was performed at the Jet Propulsion Laboratory, California Institute\nof Technology, under contract with NASA. YLY was supported as a guest investigator on the Pioneer-Venus Project under contract NAG 2267 to the California Institute of Technology.\n\nPublished - grl3709.pdf
", "abstract": "A discharge flow apparatus with chemiluminescence detector has been used to study the reaction O + ClO \u2192 Cl + O2^*, where O_2^* = O_2(a^\u00b9\u0394_g) or O_2(b^\u00b9\u03a3^+g). The measured quantum yields for producing O-2(a6\u00b9\u0394-g) and O-2(b6\u00b9\u03a3^+_g) in the above reaction are less than 2.5 \u00d7 10^(\u22122) and equal to (4.4 \u00b1 1.1) \u00d7 10^(\u22124), respectively. The observed O_2(a^\u00b9\u0394_g) airglow of Venus cannot be explained in the context of standard photochemistry using our experimental results and those reported in recent literature. The possibility of an alternative source of O atoms derived from SO_2 photolysis in the mesosphere of Venus is suggested.", "date": "1987-09", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "14", "number": "9", "publisher": "American Geophysical Union", "pagerange": "949-952", "id_number": "CaltechAUTHORS:20140915-133858164", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140915-133858164", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NAG 2267" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/GL014i009p00949", "primary_object": { "basename": "grl3709.pdf", "url": "https://authors.library.caltech.edu/records/wsap7-ye533/files/grl3709.pdf" }, "resource_type": "article", "pub_year": "1987", "author_list": "Leu, Ming-Taun and Yung, Yuk L." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/s313e-vv188", "eprint_id": 49357, "eprint_status": "archive", "datestamp": "2023-08-22 04:43:12", "lastmod": "2023-10-17 21:21:01", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Shia-Run-Lie", "name": { "family": "Shia", "given": "Run-Lie" }, "orcid": "0000-0003-1911-3120" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Radiative transfer in a sphere illuminated by a parallel beam - an integral equation approach", "ispublished": "pub", "full_text_status": "public", "keywords": "planets: atmospheres - radiative transfer", "note": "\u00a9 1986 American Astronomical Society.\n\nProvided by the NASA Astrophysics Data System.\n\nReceived 1985 February 15; accepted 1985 June 4.\n\nWe thank K. S. K. Chow, L. W. Esposito, A. J. Friedson, R.\nM. Goody, and N. D. Sze for helpful discussions. The search\nfor a variational principle for the planetary problem was\nassigned as one of the research topics in Professor R. M.\nGoody's class on atmospheric radiation at Harvard in 1972.\nThe length of time it has taken to solve the problem is perhaps\na measure of the sagacity of the master and the stupidity of the\npupil (Y. L. Y.). The research is supported by NASA grant\nNSG 7376 under the Planetary Atmospheres Program.\n\nPublished - 1986ApJ___301__554S.pdf
", "abstract": "The problem of multiple scattering of nonpolarized light in a planetary body of arbitrary shape illuminated\nby a parallel beam is formulated using the integral equation approach. There exists a simple functional whose\nstationarity condition is equivalent to solving the equation of radiative transfer and whose value at the stationary\npoint is proportional to the differential cross section. Our analysis reveals a direct relation between the\nmicroscopic symmetry of the phase function for each scattering event and the macroscopic symmetry of the\ndifferential cross section for the entire planetary body, and the inter-connection of these symmetry relations\nand the variational principle. The case of a homogeneous sphere containing isotropic scatterers is investigated\nin detail. It is shown that the solution can be expanded in a multipole series such that the general spherical\nproblem is reduced to solving a set of decoupled integral equations in one dimension. Computations have\nbeen performed for a range of parameters of interest, and illustrative examples of applications to planetary\nproblems are provided.", "date": "1986-02-15", "date_type": "published", "publication": "Astrophysical Journal", "volume": "301", "number": "2", "publisher": "American Astronomical Society", "pagerange": "554-570", "id_number": "CaltechAUTHORS:20140908-150910488", "issn": "0004-637X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140908-150910488", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NSG 7376" } ] }, "other_numbering_system": { "items": [ { "id": "4084", "name": "Caltech Division of Geological and Planetary Sciences" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1086/163923", "primary_object": { "basename": "1986ApJ___301__554S.pdf", "url": "https://authors.library.caltech.edu/records/s313e-vv188/files/1986ApJ___301__554S.pdf" }, "resource_type": "article", "pub_year": "1986", "author_list": "Shia, Run-Lie and Yung, Yuk L." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/d5fvh-j4552", "eprint_id": 49484, "eprint_status": "archive", "datestamp": "2023-08-22 04:41:39", "lastmod": "2023-10-17 21:28:35", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Pinto-J-P", "name": { "family": "Pinto", "given": "Joseph P." } }, { "id": "Lunine-J-I", "name": { "family": "Lunine", "given": "Jonathan I." }, "orcid": "0000-0003-2279-4131" }, { "id": "Kim-S-J", "name": { "family": "Kim", "given": "Sang-Joon" } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "D to H ratio and the origin and evolution of Titan's atmosphere", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 1986 Nature Publishing Group. Received 20 May; accepted 14 October 1985. We thank Mark Allen, Larry Nyquist, AI Laufer, Ray Reynolds and Dave Stevenson for useful discussions and Catherine de Bergh, Barry Lutz, Tobias Owen, Sam Epstein and Jongmann Yang for communication of their results before publication. This research was supported by NASA grants NAGW-254 and NSG 7376 to the California Institute of Technology. Contribution no. 4164 of the Division of Geological and Planetary Sciences, California Institute of Technology.", "abstract": "A value of 1.7 \u00d7 10^(\u22123) has been reported for the ratio of CH_3D to CH_4 in the stratosphere of the saturnian moon Titan. A lower value of 6 \u00d7 10^(\u22124) for this ratio in the deeper part of Titan's atmosphere was reported by de Bergh et al. For comparison we note that the CH_3D to CH_4 ratio on Saturn and Jupiter is 8.7 \u00d7 10^(\u22125) and 6.7 \u00d7 10^(\u22125), respectively (see Table 1). We estimate the uncertainties in all these observations and data reduction to be about a factor of 2. Despite these uncertainties it appears that Titan's atmosphere is enriched in deuterium by a factor of \u22653 relative to Jupiter and Saturn. Potential causative factors examined here for this enrichment are condensation to form tropospheric methane clouds, fractionation occurring over a hypothetical CH_4\u2013C_2H_6 ocean and between the ocean and the clathrate crust beneath, fractionation which occurred during the formation of Titan and fractionation occurring as a result of the evolution of Titan's atmosphere. We conclude that the greater part of the observed fractionation is probably derived from the formation of Titan and the subsequent evolution of Titan's atmosphere driven by photochemistry.", "date": "1986-01-30", "date_type": "published", "publication": "Nature", "volume": "319", "number": "6052", "publisher": "Nature Publishing Group", "pagerange": "388-390", "id_number": "CaltechAUTHORS:20140909-091900680", "issn": "0028-0836", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140909-091900680", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NAGW-254" }, { "agency": "NASA", "grant_number": "NSG 7376" } ] }, "other_numbering_system": { "items": [ { "id": "4164", "name": "Caltech Division of Geological and Planetary Sciences" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1038/319388a0", "resource_type": "article", "pub_year": "1986", "author_list": "Pinto, Joseph P.; Lunine, Jonathan I.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/yrpc2-cbp35", "eprint_id": 49184, "eprint_status": "archive", "datestamp": "2023-08-22 04:35:39", "lastmod": "2023-10-17 21:11:57", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Froidevaux-L", "name": { "family": "Froidevaux", "given": "Lucien" } }, { "id": "Allen-M-A", "name": { "family": "Allen", "given": "Mark" } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "A critical analysis of ClO and O_3 in the mid-latitude stratosphere", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1985 by the American Geophysical Union.\n\nPaper number 5D0467.\n\nReceived August 13, 1984;\nrevised April 9, 1985;\naccepted April 17, 1985.\nThis work was facilitated by discussions and communications (often in advance of publication)\nwith many individuals. In this respect, we thank J. W.\nBirks, W. B. DeMore, R. L. de Zafra, P. Fabian, C. B.\nFarmer, J. E. Frederick, G. W. Kattawar, L. F. Keyser, M.\nT. Leu, J. J. Margitan, R. T. Menzies, M. j. Moiina, S.S.\nPrasad, O. F. Raper, S. P. Sander, N. D. Sze, P.M. Solomon,\nand J. W. Waters. This research was supported by\nNASA grant NAGW-413.\nContribution 4011 of the Division of Geological and\nPlanetary Sciences, California Institute of Technology.\n\nPublished - jgrd415.pdf
", "abstract": "In the upper stratosphere, an altitude range in which ozone should be in photochemical steady-state, calculated ozone abundances that are derived from a one-dimensional photochemical model with updated chemistry are up to 60% smaller than mean observed values. On the other hand, the model results for the key free radicals (HO_x, NO_x, and ClO_x species) in the catalytic destruction of ozone are shown to be in reasonable agreement with available measurements. The general validity of the model simulation of ClO_x chemistry is confirmed through a detailed intercomparison between the computed ClO diurnal variation and recently published ground-based microwave observations. Since many field measurements are performed near sunrise or sunset, the uncertainties in the model results arising from the details of the radiation field calculations at large zenith angles are discussed. Although the calculated ozone discrepancy could be the result of a number of errors in adopted photochemical parameters, a sensitivity analysis shows that no reasonable change in any one or two parameters can resolve this problem. The limited available observations regarding the ratio of atomic oxygen to ozone suggest a possible discrepancy in that quantity, which could be responsible for a large part of the ozone problem.", "date": "1985-12-20", "date_type": "published", "publication": "Journal of Geophysical Research D", "volume": "90", "number": "D7", "publisher": "American Geophysical Union", "pagerange": "12999-13029", "id_number": "CaltechAUTHORS:20140903-100531089", "issn": "0148-0227", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140903-100531089", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NAGW-413" } ] }, "other_numbering_system": { "items": [ { "id": "4011", "name": "Caltech Division of Geological and Planetary Sciences" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/JD090iD07p12999", "primary_object": { "basename": "jgrd415.pdf", "url": "https://authors.library.caltech.edu/records/yrpc2-cbp35/files/jgrd415.pdf" }, "resource_type": "article", "pub_year": "1985", "author_list": "Froidevaux, Lucien; Allen, Mark; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/1d5z6-zp721", "eprint_id": 48697, "eprint_status": "archive", "datestamp": "2023-08-22 04:29:03", "lastmod": "2023-10-17 20:21:33", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "DeMore-W-B", "name": { "family": "DeMore", "given": "William B." } }, { "id": "Leu-M-T", "name": { "family": "Leu", "given": "Ming-Taun" } }, { "id": "Smith-R-H", "name": { "family": "Smith", "given": "Roland H." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Laboratory Studies on the Reactions between Chlorine, Sulfur Dioxide, and Oxygen: Implications for the Venus Stratosphere", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 1985 by Academic Press, Inc. Received 6 December 1984, Revised 13 March 1985, Available online 26 October 2002. Contribution number 4157 of the Division of Geological\nand Planetary Sciences, California Institute of Technology, Pasadena, Calif. 91125. R.H.S. records his appreciation to Jet Propulsion Laboratory for hospitality and financial support while on study leave from Macquarie University, Sydney. Australia. Valuable discussions with members of JPL\nchemical kinetics and photochemistry group, particularly\nJim Goble, Jim Margitan, and S. P. Sander, are gratefully acknowledged. Y.L.Y. thanks D. M. Hunten and J. M. Rodriquez for helpful discussions. The research described in this paper was performed at Jet Propulsion Laboratory, California Institute of Technology, under contract with the National Aeronautics and Space Administration and NASA Contract NAG2-267 to the California Institute of Technology.", "abstract": "The title reaction was studied by photolyzing mixtures of Cl_2 and SO_2 with and without O_2 present in an atmosphere of N_2, using Fourier transform infrared spectrophotometry to monitor reactants and products. In the absence of oxygen, sulfur dioxide is quantitatively converted to sulfuryl chloride. With 10 to 150 Torr O_2 present H_2SO_4 is produced as well as SO_2Cl_2. When a number of speculative reactions inferred from these experiments are added to a published model for Venus stratospheric chemistry, it emerges that SO_2Cl_2 is a key reservoir species for chlorine and that the reaction between Cl and So_2 provides an important cycle for destroying O_2 and converting SO_2 to H_2SO_4. The modified model could provide a possible solution to the photochemistry of the Venus stratosphere if the mixing ratio of chlorine on Venus were as high as 8 ppm.", "date": "1985-09", "date_type": "published", "publication": "Icarus", "volume": "63", "number": "3", "publisher": "Elsevier", "pagerange": "347-353", "id_number": "CaltechAUTHORS:20140819-152840216", "issn": "0019-1035", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140819-152840216", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "JPL/Caltech/NASA" }, { "agency": "NASA", "grant_number": "NAG2-267" } ] }, "other_numbering_system": { "items": [ { "id": "4157", "name": "Caltech Division of Geological and Planetary Sciences" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/0019-1035(85)90051-X", "resource_type": "article", "pub_year": "1985", "author_list": "DeMore, William B.; Leu, Ming-Taun; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/6h85a-d7w32", "eprint_id": 48695, "eprint_status": "archive", "datestamp": "2023-08-22 04:01:07", "lastmod": "2023-10-17 20:21:25", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Chow-K-S-K", "name": { "family": "Chow", "given": "Kenneth S. K." } }, { "id": "Friedson-A-J", "name": { "family": "Friedson", "given": "A. James" } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "A Note on the Variational Method of Stokes and DeMarcus for Radiative Transfer in Planetary Atmospheres", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 1984 by Academic Press, Inc. Received June 15, 1983; revised April 16, 1984. Available online 26 October 2002. Contribution 3894 of the Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, Calif. 91125. One of us (Y.L.Y.) acknowledges helpful discussions with N.D. Sze and R. M. Goody. This research\nwas supported by NASA Grant NSG 7376 to California\nInstitute of Technology.", "abstract": "A generalized functional which yields the Milne integral equation on variation and whose extremum value is proportional to the reflectivity at arbitrary emergent angle is proposed. A similar functional exists for computing the transmissivity at arbitrary emergent angle. This work is a generalization of the variational method of Stokes and DeMarcus (1971, Icarus 14, 307) based on the principle of reciprocity. In the special case of trial functions that are linear in the undetermined parameters, the calculation is greatly simplified. The computational value of our variational principle is demonstrated.", "date": "1984-08", "date_type": "published", "publication": "Icarus", "volume": "59", "number": "2", "publisher": "Elsevier", "pagerange": "177-187", "id_number": "CaltechAUTHORS:20140819-145831347", "issn": "0019-1035", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140819-145831347", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NSG 7376" } ] }, "other_numbering_system": { "items": [ { "id": "3894", "name": "Caltech Division of Geological and Planetary Sciences" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/0019-1035(84)90021-6", "resource_type": "article", "pub_year": "1984", "author_list": "Chow, Kenneth S. K.; Friedson, A. James; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/vnej4-8y918", "eprint_id": 49480, "eprint_status": "archive", "datestamp": "2023-08-22 03:59:12", "lastmod": "2023-10-17 21:28:21", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Allen-M-A", "name": { "family": "Allen", "given": "Mark" } }, { "id": "Pinto-J-P", "name": { "family": "Pinto", "given": "Joseph P." } } ] }, "title": "Photochemistry of the atmosphere of Titan: comparison between model and observations", "ispublished": "pub", "full_text_status": "public", "keywords": "planets: abundances; planets: atmospheres; planets: satellites; planets: Saturn", "note": "\u00a9 1984 The American Astronomical Society.\n\nReceived 1983 August 29; accepted 1984 January 6.\n\nWe thank A. H. Laufer, M. R. Berman, M. C. Lin, H.\nOkabe, A. M. Renlund, R. Hanel, W. Maguire, R. E. Samuelson, D. M. Hunten, D. E. Shemansky, D. F. Strobel, V.\nMcKoy, T. Owen, and D. O. Muhleman for communication of results prior to publication, and W. B. DeMore, W. T.\nHuntress, Jr., S. Trajmar, M. B. McElroy, R. M. Goody, C.\nSagan, R. K. Sparks, L. C. Lee, and K. Rages for helpful\ndiscussions. This research was supported by NASA grants\nNAGW-254 and NSG 7376 to the California Institute of\nTechnology.\n\nPublished - 1984ApJS___55__465Y.pdf
", "abstract": "The photochemistry of simple molecules containing carbon, hydrogen, nitrogen, and oxygen atoms in the atmosphere of Titan has been investigated using updated chemical schemes and our own estimates of a number of key rate coefficients. Proper exospheric boundary conditions, vertical transport, and condensation processes at the tropopause have been incorporated into the model. It is argued that the composition, climatology, and evolution of Titan's atmosphere are controlled by five major processes: (a) photolysis and photosensitized dissociation of CH_4 ; (b) conversion of H to H_2 and escape of hydrogen; (c) synthesis of higher hydrocarbons; (d) coupling between nitrogen and hydrocarbons; (e) coupling between oxygen and hydrocarbons. Starting with N_2, CH_4, and H_20, and invoking interactions with ultraviolet sunlight, energetic electrons, and cosmic rays, the model satisfactorily accounts for the concentrations of minor species observed by the Voyager IRIS and UVS instruments. Photochemistry is responsible for converting the simpler atmospheric species into more complex organic compounds, which are subsequently condensed at the tropopause and deposited on the surface. Titan might have lost 5.6 \u00d7 10^4 , 1.8 \u00d7 10^3, and 4.0 g cm^-2 , or the equivalent of 8,0.25, and 5 \u00d7 10^-4 bars of CH_4, N_2 , and CO, respectively, over geologic time. Implications of abiotic organic synthesis on Titan for the origin of life on Earth are briefly discussed.", "date": "1984-07", "date_type": "published", "publication": "Astrophysical Journal Supplement Series", "volume": "55", "number": "3", "publisher": "American Astronomical Society", "pagerange": "465-506", "id_number": "CaltechAUTHORS:20140909-090508298", "issn": "0067-0049", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140909-090508298", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NAGW-254" }, { "agency": "NASA", "grant_number": "NSG 7376" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1086/190963", "primary_object": { "basename": "1984ApJS___55__465Y.pdf", "url": "https://authors.library.caltech.edu/records/vnej4-8y918/files/1984ApJS___55__465Y.pdf" }, "resource_type": "article", "pub_year": "1984", "author_list": "Yung, Yuk L.; Allen, Mark; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/gmz3h-8fh13", "eprint_id": 49178, "eprint_status": "archive", "datestamp": "2023-08-22 03:58:25", "lastmod": "2023-10-17 21:11:38", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Allen-M-A", "name": { "family": "Allen", "given": "Mark" } }, { "id": "Lunine-J-I", "name": { "family": "Lunine", "given": "Jonathan I." }, "orcid": "0000-0003-2279-4131" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "The vertical distribution of ozone in the mesosphere and lower thermosphere", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1984 by the American Geophysical Union.\n\nReceived June 13, 1983;\nrevised December 5, 1983;\naccepted December 5, 1983.\n\nPaper number 3D1922.\n\nThe many conversations we have had\nwith S. Solomon have been of significant help in writing\nthis paper. We also gratefully acknowledge the variety of\nassistance received from D. Anderson, G. Anderson, T.\nClancy, W. DeMore, J. Gille, D. Hunten, F. Kaufman, L.\nKeyser, M. Leu, J. Logan, D. Muhleman, M. Prather, S.\nSander, P. Schwartz, J. Waters, and W. Wilson. This\nresearch was supported by NASA grant NAGW 413 and\nJPL49-649-20320-0-3270 to the California Institute of\nTechnology. Contribution number 3876 from the Division\nof Geological and Planetary Sciences, California Institute of\nTechnology.\n\nPublished - jgrd64.pdf
", "abstract": "An assessment is made of the ability of current theory to explain the phenomenology of upper atmospheric ozone as revealed by the sizeable body of measurements presently available. The chemistry of ozone in the mesosphere and lower thermosphere is closely coupled to the chemistries of other oxygen/hydrogen-containing species, which must be considered concurrently. To provide insight into the sensitivity of model calculations to the choice of values used for key chemical rate constants and climatological parameters, simple analytical expressions for ozone are derived for those situations when it is in photochemical steady state, the mesosphere during daylight hours and the lower thermosphere throughout the full diurnal period. The model is found to reproduce the detailed Aladdin 74 rocket measurements of ozone from 50 to 95 km, numerous other measurements of mid-latitude ozone in the lower mesosphere, the secondary maximum in the ozone vertical distribution at the mesopause, and the diurnal variability of ozone seen in the radio measurements of Wilson and Schwartz (1981) and other observations. The agreement with the Aladdin 74 data results from adjusting some key parameters within the uncertainties of laboratory measurements or known natural climatological variability. The variety of mid-latitude observations can be understood in terms of the estimated variability of environmental factors: diurnal, seasonal, and solar cycles in the solar illumination; the abundance of water vapor; and the details of the thermal profile of the atmosphere. The ozone secondary maximum results from the onset of the coupling between active-hydrogen and active-oxygen chemistry and its observed variability may be a consequence of secular changes in mesopause dynamics. Above \u223c95 km, ozone observations are consistently higher than model results and cannot be accounted for by the set of reactions currently included in the model.", "date": "1984-06-20", "date_type": "published", "publication": "Journal of Geophysical Research D", "volume": "89", "number": "D3", "publisher": "American Geophysical Union", "pagerange": "4841-4872", "id_number": "CaltechAUTHORS:20140903-090727251", "issn": "0148-0227", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140903-090727251", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NAGW 413" }, { "agency": "JPL", "grant_number": "49-649-20320-0-3270" } ] }, "other_numbering_system": { "items": [ { "id": "3876", "name": "Caltech Division of Geological and Planetary Sciences" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/JD089iD03p04841", "primary_object": { "basename": "jgrd64.pdf", "url": "https://authors.library.caltech.edu/records/gmz3h-8fh13/files/jgrd64.pdf" }, "resource_type": "article", "pub_year": "1984", "author_list": "Allen, Mark; Lunine, Jonathan I.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/51hc5-1k274", "eprint_id": 52776, "eprint_status": "archive", "datestamp": "2023-08-22 03:50:51", "lastmod": "2023-10-18 21:04:33", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Matteson-D-S", "name": { "family": "Matteson", "given": "Donald S." } }, { "id": "Lunine-J-I", "name": { "family": "Lunine", "given": "Jonathan I." }, "orcid": "0000-0003-2279-4131" }, { "id": "Stevenson-D-J", "name": { "family": "Stevenson", "given": "David J." }, "orcid": "0000-0001-9432-7159" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Acetylene on Titan - Reply", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 1984 American Association for the Advancement of Science.", "abstract": "We acknowledge the rather explosive\nproperties of pure, solid acetylene, as\nnoted by Matteson. However, we envision\nthe composition of the solid material\nunderlying the ethane-methane ocean to\nbe considerably more complicated than\npure acetylene, as we suggest briefly in\nour report. The dissociation of methane\nand consequent production of hydrocarbons\nin the Titan stratosphere from\nmethane must produce not only C_2 and\nC_3 hydrocarbons but also much heavier\nlong-chain polymers (incorporating nitrogen),\nat the expense, in part, of acetylene.", "date": "1984-03-16", "date_type": "published", "publication": "Science", "volume": "223", "number": "4641", "publisher": "American Association for the Advancement of Science", "pagerange": "1131", "id_number": "CaltechAUTHORS:20141212-141906993", "issn": "0036-8075", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20141212-141906993", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1126/science.223.4641.1131-b", "resource_type": "article", "pub_year": "1984", "author_list": "Matteson, Donald S.; Lunine, Jonathan I.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/83sdq-pvp45", "eprint_id": 49566, "eprint_status": "archive", "datestamp": "2023-08-22 03:48:12", "lastmod": "2023-10-17 21:33:21", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Ajello-J-M", "name": { "family": "Ajello", "given": "J. M." } }, { "id": "Shemansky-D-E", "name": { "family": "Shemansky", "given": "D." }, "orcid": "0000-0001-7168-871X" }, { "id": "Kwok-T-L", "name": { "family": "Kwok", "given": "T. L." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Y. L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Studies of extreme-ultraviolet emission from Rydberg series of H_2 by electron impact", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1984 The American Physical Society. Received 19 May 1983.\nPublished in the issue dated February 1984. The authors thank J. A. R. Samson for interesting discussions of polarization, S. K. Srivastava for the electron gun design, and E. C. Zipf for valuable discussions. The authors also wish to thank M. Glass-Maujean and J. Y. Roncin for valuable discussions and for communicating unpublished data. This work was supported by the U.S. Air Force Office of Scientific Research (AFOSR) Planetary Atmospheres and Astronomy/Relativity Programs of National Aeronautics and Space Administration (NASA). It represents one phase of work sponsored by NASA under Contract No. NAS7-100 to the Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109. This work was also supported by NASA, Division of Planetary Sciences Grant No. NAGW-106.\n\nPublished - PhysRevA.29.636.pdf
", "abstract": "Electron excitation cross sections have been measured for the following two Rydberg series of H_2: ^1\u03a3_u^+ 1s\u03c3np\u03c3 (B, B\u2032, and B\", states with principal quantum numbers n=2, 3, and 4, respectively) and ^1\u03a0_u 1s\u03c3np\u03c0 (C, D, and D\u2032 states with principal quantum numbers n=2, 3, and 4, respectively) over the energy range from threshold to 350 eV. The cross sections for these six states account for all (>99%) of the vacuum-ultraviolet emission (78-170 nm) of the singlet states of H_2. The estimated total direct-excitation cross sections for these six states at 100 eV in decreasing value are (4.02\u00b10.60)\u00d710^(\u221217) cm^2 for B^1\u03a3_u^+ (3.86\u00b10.60)\u00d710^(\u221217) cm^2 for C^1\u03a0_u, (0.76\u00b10.11)\u00d710^(\u221217) cm^2 for D^1\u03a0_u, (0.76\u00b10.11)\u00d710^(\u221217) cm^2 for B' ^1\u03a3_u^+, (0.30\u00b10.06)\u00d710^(\u221217) cm^2 for D\u2032^1\u03a0_u, and (0.23\u00b10.05)\u00d710^(\u221217) cm^2 for B\"^1\u03a3_u^+ and, additionally, (0.43\u00b10.10)\u00d710^(\u221217) cm^2 for E,F^1\u03a3_g^+ which populates the B^1\u03a3_u^+ state through radiative cascade transitions. We estimate the predissociation (autoionization is weak) and emission yields of the vibrational levels of the D, D\u2032, and B\" states whose band systems exhibit strong \"breaking off in emission\" for wavelengths below 85 nm. Furthermore, we report the first direct measurement of the dissociative excitation cross section for production of Lyman-\u03b2 of (8.9\u00b13.0)\u00d710^(\u221219) cm^2 at 100 eV. In particular, it is shown that the high-lying Rydberg states (n=3 and 4) make a substantial contribution to the observed emission below 110 nm while above 110 nm the Lyman bands (B^1\u03a3_u^+\u2192X^1\u03a3_g^+) and Werner bands (C^1\u03a0_u\u2192X^1\u03a3_g^+), the first members of the Rydberg series, dominate the spectrum. As a result of these measurements and spectroscopic models the ultraviolet (UV) spectrum from H_2 by electron impact can serve as an intensity calibration standard from 80 to 170 nm.", "date": "1984-02", "date_type": "published", "publication": "Physical Review A", "volume": "29", "number": "2", "publisher": "American Physical Society", "pagerange": "636-653", "id_number": "CaltechAUTHORS:20140910-155006837", "issn": "1050-2947", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140910-155006837", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Air Force Office of Scientific Research (AFOSR)" }, { "agency": "NASA", "grant_number": "NAS7-100" }, { "agency": "NASA", "grant_number": "NAGW-106" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1103/PhysRevA.29.636", "primary_object": { "basename": "PhysRevA.29.636.pdf", "url": "https://authors.library.caltech.edu/records/83sdq-pvp45/files/PhysRevA.29.636.pdf" }, "resource_type": "article", "pub_year": "1984", "author_list": "Ajello, J. M.; Shemansky, D.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/c07r0-pg048", "eprint_id": 49947, "eprint_status": "archive", "datestamp": "2023-08-22 03:46:32", "lastmod": "2023-10-17 22:23:47", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Friedson-A-J", "name": { "family": "Friedson", "given": "A. James" } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "The thermosphere of Titan", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1984 American Geophysical Union.\n\nReceived August 30, 1982; revised October 10, 1983; accepted October 11, 1983.\n\nThe authors wish to thank A. P. Ingersoll, M. Allen, M. E. Summers, and G. R. Gladstone for helpful discussions.\nThis research was supported by NASA grant NSG 7376 to the California Institute of Technology. Contribution 3907 from the Division of Geological and Planetary SciencesC, alifornia Institute of Technology. The Editor thanks R. E. Hartle and D. Strobel for their assistance in evaluating this paper.\n\nPublished - jgra6875.pdf
", "abstract": "The diurnal variation of the vertical structure of Titan's thermosphere is calculated through simultaneous solution of the equations of heat transfer and hydrostatic equilibrium. The temperature and density profiles are found above the mesopause. The dynamical response of the thermosphere to heating is for the most part neglected. Nevertheless, we are able to draw some interesting qualitative and quantitative conclusions regarding the vertical structure. Heating of the upper thermosphere occurs primarily through absorption of solar Lyman \u03b1 radiation by methane, with an additional amount of heating (\u227220%) due to low-energy magnetospheric electron precipitation. The heat is conducted downward to the mesopause, where it is removed by IR cooling due principally to acetylene. The mesopause is found to occur where the density is 2.2\u00d710^(12) cm^(\u22123) (736 km), and has a temperature of \u223c110 K. The exospheric temperature is unlikely to exceed 225 K in the course of a Titan day. The diurnally averaged exospheric temperature is in the range 187\u2013197 K depending on the amount of magnetospheric electron heating that is included in the model. The amplitude of the diurnal variation is found to be \u227228 K. We find that the vertical extent of the hydrogen cloud is too large to be explained in terms of simple thermal escape of hydrogen from a \u223c225-K exosphere, and we conclude that other processes must be important for populating or heating the neutral torus.", "date": "1984-01", "date_type": "published", "publication": "Journal of Geophysical Research A", "volume": "89", "number": "A1", "publisher": "American Geophysical Union", "pagerange": "85-90", "id_number": "CaltechAUTHORS:20140923-133141023", "issn": "0148-0227", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140923-133141023", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NSG 7376" } ] }, "other_numbering_system": { "items": [ { "id": "3907", "name": "Caltech Division of Geological and Planetary Sciences" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/JA089iA01p00085", "primary_object": { "basename": "jgra6875.pdf", "url": "https://authors.library.caltech.edu/records/c07r0-pg048/files/jgra6875.pdf" }, "resource_type": "article", "pub_year": "1984", "author_list": "Friedson, A. James and Yung, Yuk L." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/nd1tz-n2q60", "eprint_id": 42492, "eprint_status": "archive", "datestamp": "2023-08-22 03:42:47", "lastmod": "2023-10-25 16:42:59", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Lunine-J-I", "name": { "family": "Lunine", "given": "Jonathan I." }, "orcid": "0000-0003-2279-4131" }, { "id": "Stevenson-D-J", "name": { "family": "Stevenson", "given": "David J." }, "orcid": "0000-0001-9432-7159" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Ethane Ocean on Titan", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 1983 American Association for the Advancement of Science. \n\nPublished 16 DECEMBER, 1983; 30 June 1983; accepted 27 September 1983. \n\nWe thank J. Pearl, D.M. Hunten, and C. Sagan for helpful discussions and R.E. Samuelson and F.M. Flasar for detailed reviews of the manuscript. Supported by NASA grants NSG 7376 and NAGW 185. Contribution number 3933 from the Division of Geological and Planetary Sciences, California Institute of Technology.", "abstract": "It is proposed that Saturn's satellite Titan is covered by an ocean one to several kilometers deep consisting mainly of ethane. If the ocean is in thermodynamic equilibrium with an atmosphere of 3 percent (mole fraction) methane, then its composition is roughly 70 percent ethane, 25 percent methane, and 5 percent nitrogen. Photochemical models predict that ethane is the dominant end product of methane photolysis so that the evolving ocean is both the source and sink for continuing photolysis. The coexisting atmosphere is compatible with Voyager data.", "date": "1983-12-16", "date_type": "published", "publication": "Science", "volume": "222", "number": "4629", "publisher": "American Association for the Advancement of Science", "pagerange": "1229-1230", "id_number": "CaltechAUTHORS:20131115-103723523", "issn": "0036-8075", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20131115-103723523", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NSG-7376" }, { "agency": "NASA", "grant_number": "NAGW-185" } ] }, "other_numbering_system": { "items": [ { "id": "3933", "name": "Caltech Division of Geological and Planetary Sciences" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "resource_type": "article", "pub_year": "1983", "author_list": "Lunine, Jonathan I.; Stevenson, David J.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/2pfc5-3ma59", "eprint_id": 48369, "eprint_status": "archive", "datestamp": "2023-08-22 03:40:44", "lastmod": "2023-10-17 18:45:19", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Laufer-A-H", "name": { "family": "Laufer", "given": "A. H." } }, { "id": "Gardner-E-P", "name": { "family": "Gardner", "given": "E. P." } }, { "id": "Kwok-T-L", "name": { "family": "Kwok", "given": "T. L." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Y, L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Computations and Estimates of Rate Coefficients for Hydrocarbon Reactions of Interest to the Atmospheres of the Outer Solar System", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 1983 Academic Press, Inc.\n\nReceived May 4, 1983; revised August 8, 1983.\n\nThis work was supported by the NASA Planetary Atmospheres Program.", "abstract": "The rate coefficients, including Arrhenius parameters, have been computed for a number of chemical reactions involving hydrocarbon species for which experimental data are not available and which are important in planetary atmospheric models. The techniques used to calculate the kinetic parameters include the Troe and semiempirical bond energy-bond order (BEBO) or bond strength-bond length (BSBL) methods.", "date": "1983-12", "date_type": "published", "publication": "Icarus", "volume": "56", "number": "3", "publisher": "Elsevier", "pagerange": "560-567", "id_number": "CaltechAUTHORS:20140812-085131127", "issn": "0019-1035", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140812-085131127", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA Planetary Atmospheres Program" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/0019-1035(83)90173-2", "resource_type": "article", "pub_year": "1983", "author_list": "Laufer, A. H.; Gardner, E. P.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/x1ecx-v9159", "eprint_id": 49950, "eprint_status": "archive", "datestamp": "2023-08-22 03:40:21", "lastmod": "2023-10-17 22:23:54", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Samuelson-R-E", "name": { "family": "Samuelson", "given": "R. E." } }, { "id": "Maguire-W-C", "name": { "family": "Maguire", "given": "W. C." } }, { "id": "Hanel-R-A", "name": { "family": "Hanel", "given": "R. A." } }, { "id": "Kunde-V-G", "name": { "family": "Kunde", "given": "V. G." } }, { "id": "Jennings-D-E", "name": { "family": "Jennings", "given": "D. E." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Y. L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Aikin-A-C", "name": { "family": "Aikin", "given": "A. C." } } ] }, "title": "CO_2 on Titan", "ispublished": "pub", "full_text_status": "public", "note": "This paper is not subject to U.S. copyright. Published in 1983 by the American Geophysical Union. Received September 28, 1982; revised March 16, 1983; accepted March 17, 1983. \n\nPaper number 3A0453. \n\nWe thank J. Fox and R. Prinn for useful discussions. Y. L. Yung acknowledges support by NASA grant NAGW-254 to the California Institute of Technology. The Editor thanks D. F. Strobel and D. E. Shemansky for their assistance in evaluating this paper.\n\nPublished - jgra6766.pdf
", "abstract": "A sharp stratospheric emission feature at 667 cm^(\u22121) in the Voyager infrared spectra of Titan is associated with the \u03bd_2 Q branch of CO_2. A coupling of photochemical and radiative transfer theory yields an average mole fraction above the 110 mbar level of \u0192CO_2 = 1.5 \u00b1 ^(1.5)_(0.8) x 10^(-9), with most of the uncertainty being due to imprecise knowledge of the vertical distribution. CO_2 is found to be in a steady state, with its abundance being regulated principally by the \u223c72 K cold trap near the tropopause and secondarily by the rate at which water-bearing meteoritic material enters the top of the atmosphere. An influx of water about 0.4 times that at the top of the terrestrial atmosphere is consistent with a combination of the observed CO_2 abundance and a steady state CO mole fraction of 1.1\u00d710^(\u22124); the theoretical value for CO is close to the value observed by Lutz et al. (1983), although there are large margins for error in both numbers. If steady state conditions for CO prevail, little information is available regarding the evolution of Titan's atmosphere.", "date": "1983-11-01", "date_type": "published", "publication": "Journal of Geophysical Research A", "volume": "88", "number": "A11", "publisher": "American Geophysical Union", "pagerange": "8709-8715", "id_number": "CaltechAUTHORS:20140923-140352880", "issn": "0148-0227", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140923-140352880", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NAGW-254" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/JA088iA11p08709", "primary_object": { "basename": "jgra6766.pdf", "url": "https://authors.library.caltech.edu/records/x1ecx-v9159/files/jgra6766.pdf" }, "resource_type": "article", "pub_year": "1983", "author_list": "Samuelson, R. E.; Maguire, W. C.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/3jcr9-jzg70", "eprint_id": 49354, "eprint_status": "archive", "datestamp": "2023-08-22 03:35:42", "lastmod": "2023-10-17 21:20:55", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Summers-M-E", "name": { "family": "Summers", "given": "Michael E." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Haff-P-K", "name": { "family": "Haff", "given": "Peter K." } } ] }, "title": "A two-stage mechanism for escape of Na and K from Io", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 1983 Macmillan Journals Ltd.\n\nReceived 11 May; accepted 28 June 1983.\n\nWe thank J. Trauger, A. Dessler, and A. Summers for helpful\ndiscussions; and K. Cherrey for calculations. This research was\nsupported by NASA grants NAGW-202 and NAGW-313.\nContribution no. 3873 from the Division of Geological and\nPlanetary Sciences, California Institute of Technology.", "abstract": "It is generally accepted that Io is the source of S, O, Na and K which, after ionization, form the constituents of the Io plasma torus. The escape of S and O from Io can be understood in terms of the photochemistry of a predominantly SO_2 atmosphere created by the high vapour pressure of SO_2 (refs 1, 15). However, the vapour pressures of Na_2S, K_2S and other common compounds containing Na and K are negligible at the surface temperatures of Io. This has given rise to the suggestion that over part of Io's surface (the nightside) the atmosphere is thin enough so that surface sputtering by co-rotating ions can eject Na and K directly into the Io torus. The main objection to this idea is that it implies a 'Sun-locked' source for Na and K, while observations of the Na and K clouds around Io indicate a 'Jupiter-locked' ejection mechanism. We propose here that Na and K escape from Io in two stages. Atoms of Na and K are first sputtered into the atmosphere from the surface by high-energy magnetospheric ions. Atmospheric sputtering by low-energy co-rotating ions then removes these constituents (along with others present) out of Io's gravitational field. We suggest that the observed Na and K ejection asymmetry is due to preferential sputtering of atmospheric particles on the hemisphere of Io facing Jupiter. The estimated injection rates are sufficiently large to maintain the observed K, Na, and O clouds observed around Io.", "date": "1983-08-25", "date_type": "published", "publication": "Nature", "volume": "304", "number": "5928", "publisher": "Nature Publishing Group", "pagerange": "710-712", "id_number": "CaltechAUTHORS:20140908-143019888", "issn": "0028-0836", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140908-143019888", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NAGW-202" }, { "agency": "NASA", "grant_number": "NAGW-313" } ] }, "other_numbering_system": { "items": [ { "id": "3873", "name": "Caltech Division of Geological and Planetary Sciences" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1038/304710a0", "resource_type": "article", "pub_year": "1983", "author_list": "Summers, Michael E.; Yung, Yuk L.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/cn4zp-v6g85", "eprint_id": 49940, "eprint_status": "archive", "datestamp": "2023-08-22 03:28:16", "lastmod": "2023-10-17 22:23:27", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Pinto-J-P", "name": { "family": "Pinto", "given": "Joseph P." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Rind-D", "name": { "family": "Rind", "given": "David" } }, { "id": "Russell-G-L", "name": { "family": "Russell", "given": "Gary L." } }, { "id": "Lerner-J-A", "name": { "family": "Lerner", "given": "Jean A." } }, { "id": "Hansen-J-E", "name": { "family": "Hansen", "given": "James E." } }, { "id": "Hameed-S", "name": { "family": "Hameed", "given": "Sultan" } } ] }, "title": "A General Circulation Model Study of Atmospheric Carbon Monoxide", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1983 by the American Geophysical Union. Received October 20, 1980; revised December 31, 1982; accepted January 10, 1983. \n\nPaper number 3C0077.\n\nWe thank Elaine Matthews for helpful discussions concerning seasonality in tropical vegetation. One of us (J.P.) was supported by an NAS-NRC Resident Research Associateship during the course of this work.\n\nPublished - jgrc2966.pdf
", "abstract": "The carbon monoxide cycle is studied by incorporating the known and hypothetical sources and sinks in a tracer model that uses the winds generated by a general circulation model. Photochemical production and loss terms, which depend on OH radical concentrations, are calculated in an interactive fashion. The computed global distribution and seasonal variations of CO are compared with observations to obtain constraints on the distribution and magnitude of the sources and sinks of CO, and on the tropospheric abundance of OH. The simplest model that accounts for available observations requires a low latitude plant source of about 1.3\u00d710^(15) g yr^(\u22121), in addition to sources from incomplete combustion of fossil fuels and oxidation of methane. The globally averaged OH concentration calculated in the model is 7\u00d710^5 cm^(\u22123). Models that calculate globally averaged OH concentrations much lower than our nominal value are not consistent with the observed variability of CO. Such models are also inconsistent with measurements of CO isotopic abundances, which imply the existence of plant sources.", "date": "1983-04-20", "date_type": "published", "publication": "Journal of Geophysical Research C", "volume": "88", "number": "C6", "publisher": "American Geophysical Union", "pagerange": "3691-3702", "id_number": "CaltechAUTHORS:20140923-112101215", "issn": "0148-0227", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140923-112101215", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NAS-NRC Resident Research Associateship" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/JC088iC06p03691", "primary_object": { "basename": "jgrc2966.pdf", "url": "https://authors.library.caltech.edu/records/cn4zp-v6g85/files/jgrc2966.pdf" }, "resource_type": "article", "pub_year": "1983", "author_list": "Pinto, Joseph P.; Yung, Yuk L.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/xh9dz-g1z25", "eprint_id": 49296, "eprint_status": "archive", "datestamp": "2023-08-22 03:26:20", "lastmod": "2023-10-17 21:17:33", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Gladstone-G-R", "name": { "family": "Gladstone", "given": "G. Randall" } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "An analysis of the reflection spectrum of Jupiter from 1500 \u00c5 to 1740 \u00c5", "ispublished": "pub", "full_text_status": "public", "keywords": "planets: abundances, planets: atmospheres, planets: Jupiter,\nplanets: spectra, ultraviolet: spectra", "note": "\u00a9 American Astronomical Society. Provided by the NASA Astrophysics Data System. Received 1982 April 5; accepted 1982 August 24. \nWe would like to thank M. Allen, J. Clarke, W. Maguire, R. Panek, M. Summers, and an anonymous reviewer for helpful comments and discussions. This research was supported by NASA grant NSG-7376 of the Planetary Atmosphere Program. This\nis contribution number 3646 of the Division of Geological and Planetary Sciences, California Institute of Technology.\n\nPublished - 1983ApJ___266__415G.pdf
", "abstract": "A study is made of the UV reflection spectrum of Jupiter as measured by the International Ultraviolet Explorer. Detailed modeling reveals the mixing ratios of C_2H_2, C_2H_6, and C_4H_2 to be (1.0 \u00b1 0.1) x 10^(-1), (6.6 \u00b1 5.3) x 10^(-6), and (2.9 \u00b1 2.0) x 10^(-10), respectively, in the pressure region between ~3 and 40 mbar. Upper limits in this pressure region for the mixing ratios of C_2H_4\nand NH_3 were determined to be (3.9^(+4.9)_(-3.9))x10^(-10) and (4.2^(+6.7)_(-4.2))x10^(-9), respectively. An upper\nlimit to the optical depth of dust above the tropopause, assuming it is well mixed, is 0.2^(+0.3)_(-1.4), and\nan upper limit on the dayglow emission by the Lyman bands of H_2 is 1.4^(+2.4)_(-1.4) kR. Comparison with Voyager results suggests that the scale height of C_2H_2 in the region 150-10 mbar is approximately twice that of the bulk atmosphere, consistent with the IUE observation of cosine-like limb darkening in the north-south direction on Jupiter in this spectral range. These results are of use in the photochemical modeling of the upper atmosphere of Jupiter.", "date": "1983-03-01", "date_type": "published", "publication": "Astrophysical Journal", "volume": "266", "number": "1", "publisher": "American Astronomical Society", "pagerange": "415-424", "id_number": "CaltechAUTHORS:20140905-133412690", "issn": "0004-637X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140905-133412690", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NSG-7376" } ] }, "other_numbering_system": { "items": [ { "id": "3646", "name": "Caltech Division of Geological and Planetary Sciences" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1086/160789", "primary_object": { "basename": "1983ApJ___266__415G.pdf", "url": "https://authors.library.caltech.edu/records/xh9dz-g1z25/files/1983ApJ___266__415G.pdf" }, "resource_type": "article", "pub_year": "1983", "author_list": "Gladstone, G. Randall and Yung, Yuk L." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/zbagq-2st87", "eprint_id": 49682, "eprint_status": "archive", "datestamp": "2023-08-22 03:22:33", "lastmod": "2023-10-17 22:04:46", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Laufer-A-H", "name": { "family": "Laufer", "given": "Allan H." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Equivalence of Vinylidene and C_2H_2^*: Calculated Rate Constant for Vinylidene Abstraction from CH_4", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 1983 American Chemical Society. Publication Date: January 1983.", "abstract": "A long-lived excited state of acetylene, denoted by\nC_2H_2^*, often has been invoked as the major intermediate\nspecies in the photolysis of C_2H_2. The structure of the\nintermediate remains obscure. Recently, Laufer, on the\nbasis of spectroscopic evidence, has suggested that triplet\nvinylidene radicals (^3B_2, H_2C=C) are a possible intermediate in the vacuum ultraviolet flash photolysis of acetylene as well as the combination of two triplet CH_2 radicals. In the latter, the isotopic distribution of product acetylene supports the assignment to vinylidene.", "date": "1983-01", "date_type": "published", "publication": "Journal of Physical Chemistry", "volume": "87", "number": "1", "publisher": "American Chemical Society", "pagerange": "181-182", "id_number": "CaltechAUTHORS:20140915-075024099", "issn": "0022-3654", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140915-075024099", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1021/j100224a039", "resource_type": "article", "pub_year": "1983", "author_list": "Laufer, Allan H. and Yung, Yuk L." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/zfads-h9r32", "eprint_id": 49298, "eprint_status": "archive", "datestamp": "2023-08-22 03:12:14", "lastmod": "2023-10-17 21:17:40", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "DeMore-W-B", "name": { "family": "DeMore", "given": "W. B." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Catalytic Processes in the Atmospheres of Earth and Venus", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 1982 American Association for the Advancement of Science\n\nThe research described in this article was performed at Jet Propulsion Laboratory, California Institute of Technology, under NASA contracts NAS7-100 and NSG-7376. We are grateful for helpful comments and suggestions by several colleagues, especially M. A. Allen and W. T. Huntress.", "abstract": "Photochemical processes in planetary atmospheres are strongly influenced by catalytic effects of minor constituents. Catalytic cycles in the atmospheres of Earth and Venus are closely related. For example, chlorine oxides (CIO_x) act as catalysts in the two atmospheres. On Earth, they serve to convert odd oxygen (atomic oxygen and ozone) to molecular oxygen. On Venus they have a similar effect, but in addition they accelerate the reactions of atomic and molecular oxygen with carbon monoxide. The latter process occurs by a unique combination of CIO_x catalysis and sulfur dioxide photosensitization. The mechanism provides an explanation for the very low extent of carbon dioxide decomposition by sunlight in the Venus atmosphere.", "date": "1982-09-24", "date_type": "published", "publication": "Science", "volume": "217", "number": "4566", "publisher": "American Association for the Advancement of Science", "pagerange": "1209-1213", "id_number": "CaltechAUTHORS:20140905-140637275", "issn": "0036-8075", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140905-140637275", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NAS7-100" }, { "agency": "NASA", "grant_number": "NSG-7376" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1126/science.217.4566.1209", "resource_type": "article", "pub_year": "1982", "author_list": "DeMore, W. B. and Yung, Yuk L." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/r8sgm-58626", "eprint_id": 48696, "eprint_status": "archive", "datestamp": "2023-08-22 03:09:11", "lastmod": "2023-10-17 20:21:29", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "DeMore-W-B", "name": { "family": "DeMore", "given": "W. B." } } ] }, "title": "Photochemistry of the Stratosphere of Venus: Implications for Atmospheric Evolution", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 1982 by Academic Press, Inc. Received November 13, 1981; revised March 1, 1982. Available online 26 October 2002. Paper presented at \"An International Conference on the Venus Environment,\" Palo Alto, California, November l-6, 1981. Contribution No. 3692 of the Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, California 91125. We thank J. J. Margitan, S. H. Jaffe, L. Phillips, K. S. Bhatki, M. Patapoff, M. T. Leu, C. J. Howard, L. W. Esposito, D. 0. Muhleman, and R. T. Clancy for communication of experimental data prior to publication. We benefited from helpful discussions with M. B. McElroy, R. G. Prinn, D. M. Hunten, S. Kumar, T. M.\nDonahue,J. Blamont, 0. B. Toon, W. T. Huntress, Jr., M. Allen, and J.P. Pinto, and critical comments given by the referees Drs. S. C. Wofsy and V. A. Krasnopolsky. This research was supported by NASA Ames Research Center Grant NCC 2-61 to California Institute of Technology. This also represented one phase of NASA-sponsored research carried out at the Jet Propulsion Laboratory under Contract NAS7-100.", "abstract": "The photochemistry of the stratosphere of Venus was modeled using an updated and expanded chemical scheme, combined with the results of recent observations and laboratory studies. We examined three models, with H2 mixing ratio equal to 2 \u00d7 10^(\u22125), 5 \u00d7 10^(\u22127), and 1 \u00d7 10^(\u221213), respectively. All models satisfactorily account for the observations of CO, O_2, O_2(^1\u0394), and SO_2 in the stratosphere, but only the last one may be able to account for the diurnal behavior of mesospheric CO and the uv albedo. Oxygen, derived from CO_2 photolysis, is primarily consumed by CO_2 recombination and oxidation of SO_2 to H_2SO_4. Photolysis of HCl in the upper stratosphere provides a major source of odd hydrogen and free chlorine radicals, essential for the catalytic oxidation of CO. Oxidation of SO_2 by O occurs in the lower stratosphere. In the high-H_2 model (model A) the O-O bond is broken mainly by S + O_2 and SO + HO_2. In the low-H_2 models additional reactions for breaking the O-O bond must be invoked: NO + HO_2 in model B and ClCO + O_2 in model C. It is shown that lightning in the lower atmosphere could provide as much as 30 ppb of NO_x in the stratosphere. Our modeling reveals a number of intriguing similarities, previously unsuspected, between the chemistry of the stratosphere of Venus and that of the Earth. Photochemistry may have played a major role in the evolution of the atmosphere. The current atmosphere, as described by our preferred model, is characterized by an extreme deficiency of hydrogen species, having probably lost the equivalent of 10^2\u201310^3 times the present hydrogen content.", "date": "1982-08", "date_type": "published", "publication": "Icarus", "volume": "51", "number": "2", "publisher": "Elsevier", "pagerange": "199-247", "id_number": "CaltechAUTHORS:20140819-151226643", "issn": "0019-1035", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140819-151226643", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA Ames Research Center Grant", "grant_number": "NCC 2-61" }, { "agency": "NASA/JPL", "grant_number": "NAS7-100" } ] }, "other_numbering_system": { "items": [ { "id": "3692", "name": "Caltech Division of Geological and Planetary Sciences" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/0019-1035(82)90080-X", "resource_type": "article", "pub_year": "1982", "author_list": "Yung, Yuk L. and DeMore, W. B." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/69hbp-jxn69", "eprint_id": 49565, "eprint_status": "archive", "datestamp": "2023-08-22 03:09:20", "lastmod": "2023-10-17 21:33:19", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Froidevaux-L", "name": { "family": "Froidevaux", "given": "Lucien" } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Radiation and chemistry in the stratosphere: Sensitivity to O_2 absorption cross sections in the Herzberg continuum", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1982 American Geophysical Union.\n\nReceived April 20, 1982; accepted June 29, 1982.\n\nPaper number 2L1124.\n\nWe thank M. Allen for his assistance\nin the modeling and discussions concerning the\nSchumann-Runge bands, and W.B. DeMote for helpful comments.\nWe also thank J.R. Herman, J.E. Frederick and J.E.\nMentall for making their work available to us prior to publication\nand discussing it with us. This research was supported\nby JPL 49-649-20320-0-3270 to the California Institute\nof Technology. Contribution number 3776 from the\nDivision of Geological and Planetary Sciences, California\nInstitute of Technology, Pasadena, California 91125.\n\nPublished - grl2047.pdf
", "abstract": "We propose that a significant overestimate of the molecular oxygen absorption cross sections in the important spectral window from 200-220 nm is in large part responsible for the discrepancy between observed and modeled vertical profiles of some halocarbons (CFCl_3 in particular), as well as for the long-standing problem of simultaneously fitting N_2O, CH_4, CF_2Cl_2 and CFCl_3 profiles with a single eddy diffusion model. Recent measurements of the direct solar flux in the stratosphere by J.R. Herman and co-workers seem to support this idea. Replacing our current O_2 cross sections in the 200-220 nm range by values in better agreement with the results of the above group leads to a reduction in N_2O, CF_2Cl_2 and CFCl_3 concentrations (by factors of 0.70, 0.62 and 0.19, respectively, at 30 km), while CH_4, H_2 and CO profiles are essentially unchanged. Moreover, the predicted concentration of HNO_3 above 30 km is reduced by \u223c50%, yielding better agreement with observations. The reduction in O_2 cross sections produces a 10-20% decrease in ozone above about 35 km, but a fairly large increase (\u223c30%) near the peak around 20-25 km. The changes in other stratospheric species are also briefly discussed.", "date": "1982-08", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "9", "number": "8", "publisher": "American Geophysical Union", "pagerange": "854-857", "id_number": "CaltechAUTHORS:20140910-153752409", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140910-153752409", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "JPL", "grant_number": "49-649-20320-0-3270" } ] }, "other_numbering_system": { "items": [ { "id": "3776", "name": "Caltech Division of Geological and Planetary Sciences" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/GL009i008p00854", "primary_object": { "basename": "grl2047.pdf", "url": "https://authors.library.caltech.edu/records/69hbp-jxn69/files/grl2047.pdf" }, "resource_type": "article", "pub_year": "1982", "author_list": "Froidevaux, Lucien and Yung, Yuk L." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/pxn50-way66", "eprint_id": 49564, "eprint_status": "archive", "datestamp": "2023-08-22 03:03:11", "lastmod": "2023-10-17 21:33:16", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Ajello-J-M", "name": { "family": "Ajello", "given": "J. M." } }, { "id": "Srivastava-S-K", "name": { "family": "Srivastava", "given": "S. K." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Laboratory studies of uv emissions of H_2 by electron impact. The Werner- and Lyman-band systems", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1982 The American Physical Society. Received 1 October 1981.\nPublished in the issue dated May 1982. This work was supported by the Planetary Atmospheres, Astronomy/Relativity and Laser Kinetics Programs of NASA. It represents one phase\nof work sponsored by NASA under Contract No. NAS7-100 to the Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California 91109.\n\nPublished - PhysRevA.25.2485.pdf
", "abstract": "We report a laboratory measurement of absolute emission cross sections of both the Lyman bands (B^1\u03a3_u^+\u2192X^1\u03a3_g^+) and Werner bands (C^1\u03a0_u\u2192X^1\u03a0_g^+) of H_2 by electron impact over the energy range from threshold to 400 eV with the same optical system. We find the emission cross section for the B^1\u03a3_u^+\u2192X^1\u03a3_g^+ transition at 100 eV to be (3.55\u00b10.8) \u00d7 10^(\u221217) cm^2 (2.7 \u00d7 10^(\u221217) cm^2, direct excitation, 0.85 \u00d7 10^(\u221217) cm^2, cascading) and the emission cross section for the C^1\u03a0_u\u2192X^1\u03a3_g^+ transition at 100 eV to be (3.1\u00b10.6) \u00d7 10^(\u221217) cm^2 (cascading is estimated to be not present). The cross-section ratio Qc/Qb for direct excitation is 1.21\u00b10.30 at 300 eV in excellent agreement with published values for this ratio from theoretical calculations and experimental data of the optical oscillator strengths. We measure the cross section for cascading to the B state to be 24\u00b110% of the total emission cross section both at 100 and 300 eV. We show that cascading increases to 51\u00b120% of the total cross section of the B state at 20 eV. The vibrational population distribution of the B state is found to be a function of electron-impact energy as the importance of cascading relative to direct excitation changes with electron-impact energy.", "date": "1982-05", "date_type": "published", "publication": "Physical Review A", "volume": "25", "number": "5", "publisher": "American Physical Society", "pagerange": "2485-2498", "id_number": "CaltechAUTHORS:20140910-153452680", "issn": "1050-2947", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140910-153452680", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NAS7-100" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1103/PhysRevA.25.2485", "primary_object": { "basename": "PhysRevA.25.2485.pdf", "url": "https://authors.library.caltech.edu/records/pxn50-way66/files/PhysRevA.25.2485.pdf" }, "resource_type": "article", "pub_year": "1982", "author_list": "Ajello, J. M.; Srivastava, S. K.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/qpjsm-0a882", "eprint_id": 49292, "eprint_status": "archive", "datestamp": "2023-08-22 03:00:46", "lastmod": "2023-10-17 21:17:21", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Gladstone-G-R", "name": { "family": "Gladstone", "given": "G. Randall" } }, { "id": "Cheng-Kar-Man", "name": { "family": "Chang", "given": "Kar Man" } }, { "id": "Ajello-J-M", "name": { "family": "Ajello", "given": "Joseph M." } }, { "id": "Srivastava-S-K", "name": { "family": "Srivastava", "given": "S. K." } } ] }, "title": "H_2 fluorescence spectrum from 1200 to 1700 \u00c5 by electron impact: Laboratory study and application to Jovian aurora", "ispublished": "pub", "full_text_status": "public", "keywords": "laboratory spectra, molecular processes, planets: atmospheres", "note": "\u00a9 1982 American Astronomical Society. Provided by the NASA Astrophysics Data System. Received 1981 February 20; accepted 1981 November 20.\n\nPublished - 1982ApJ___254L__65Y.pdf
", "abstract": "A combined experimental study of the fluorescence spectrum of H_2 at wavelengths of 1200-1700 \u00c5 by electron impact and its application to modeling the Jovian aurora have been carried out. Our laboratory data suggest that at 100 eV the relative cross sections for direct excitation of Ly\u0251, Lyman\nbands (B^1\u03a3_u^+-X^1\u03a3_g^+), and Werner bands (C^1\u03c0_u-X^1\u03a3_g^+) are 1, 2.3\u00b10.6, and 2.6\u00b10.5, respectively, in conflict with Stone and Zipfs (1972) results for the Werner bands. Cascade from E,F^1\u03a3_g^+ states contributes an additional 31% to the B^1\u03a3_u^+ state population. It is shown that the most likely fate for the metastable H(2^2S) atoms produced in the Jovian aurora is collisional\nquenching to H(2^2P), and this could add as much as 60% to the predicted Ly\u0251 emission. On the basis of detailed atmospheric and radiative transfer modeling, we conclude that the recent IUE and Voyager observations are consistent with precipitation of electrons with energy in the range of 1-30 keV or other energetic particles that penetrate to number densities of 4 X 10^(10)-5 X 10^(13) cm^(-3) or\ncolumn densities of 5 X 10^(17)-2 X 10^(20) cm^(-2) in the atmosphere. The globally averaged energy flux and production of hydrogen atoms are 0.5-2 ergs cm^(-2) s^(-1) and 1-4 X 10^(10) atoms cm^(-2) s^(-1), respectively.", "date": "1982-03-15", "date_type": "published", "publication": "Astrophysical Journal Letters", "volume": "254", "number": "2", "publisher": "American Astronomical Society", "pagerange": "L65-L69", "id_number": "CaltechAUTHORS:20140905-115015917", "issn": "2041-8205", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140905-115015917", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "other_numbering_system": { "items": [ { "id": "3570", "name": "Caltech Division of Geological and Planetary Sciences" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1086/183757", "primary_object": { "basename": "1982ApJ___254L__65Y.pdf", "url": "https://authors.library.caltech.edu/records/qpjsm-0a882/files/1982ApJ___254L__65Y.pdf" }, "resource_type": "article", "pub_year": "1982", "author_list": "Yung, Yuk L.; Gladstone, G. Randall; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/2yacj-eyw53", "eprint_id": 49949, "eprint_status": "archive", "datestamp": "2023-08-22 02:45:31", "lastmod": "2023-10-17 22:23:51", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Haff-P-K", "name": { "family": "Haff", "given": "P. K." } }, { "id": "Watson-C-C", "name": { "family": "Watson", "given": "C. C." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Sputter ejection of matter from Io", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1981 by the American Geophysical Union. Received October 7, 1980; revised March 4, 1981; accepted March 5, 1981. \n\nPaper number 1A0397. \n\nOne of us (P.K.H.) would like to acknowledge the interest and support of D. A. Bromley at Yale and T. A. Tombrello\nat Caltech. We also thank G. J. Wasserburg of Caltech's Lunatic Asylum for an intense discussion on the abundance of the elements. This work was supported in part by the U.S. Department of Energy(EY-76-C-02-3074) at Yale and the National Aeronautics and Space Administration (NGR 05-002-333), the Caltech President's Fund, and the National Science Foundation (PHY79-23638) at Caltech. The Editor thanks D. Matson for his assistance in evaluating this\npaper.\n\nPublished - jgra5759.pdf
", "abstract": "The direct collisional interaction of magnetospheric particles with Io will lead to sputtering of atoms and molecules from the satellite into circum-Jovian space. The \u223c520-eV S (and \u223c260-eV O) ions composing the Io torus are the most effective agents for net sputter removal of matter from the satellite. An incident flux of \u223c10^(10) cm^(\u22122) s^(\u22121) is estimated to provide \u223c5 \u00d7 10^(10) S atoms cm^(\u22122) s^(\u22121) from sputtering of a (dayside) atmosphere with an exobase at a few hundred kilometers and up to \u223c10^(12) S atoms cm^(\u22122) s^(\u22121) from an atmosphere at 1500\u00b0K with an exobase at \u223c2.2 R_(Io). The supply of S (and O) required to stabilize the torus has been estimated by others to be from 10^(10) to 10^(12) cm^(\u22122) s^(\u22121). If Na and K are present in the atmosphere at a concentration level of 1%, the corresponding sputtering rates are calculated to be a few times 10^8 cm^(\u22122) s^(\u22121) for an exobase at several hundred kilometers. These numbers are large enough to supply the 10^7 cm^(\u22122) s^(\u22121) fluxes required to maintain the Na and K clouds. Sputtering can also remove heavy molecules, like Sn, from the atmosphere. At night, direct S sputtering of the unprotected surface is calculated to eject S and Na (1% concentration) at rates given approximately by \u223c10^(10) and \u223c10^8 cm^(\u22122) s^(\u22121), respectively. All atomic species residing on the surface must be ejected into circum-Jovian space at a rate approximately proportional to their (surface) abundances, if direct surface sputtering occurs, so that the particle content of the inner Jovian magnetosphere should map rather faithfully all species present on Io's surface. The processes of plume sputtering, avalanche cascading, and ionic saltation may lead to spatial and temporal variations in the number of ejected particles.", "date": "1981-08-01", "date_type": "published", "publication": "Journal of Geophysical Research A", "volume": "86", "number": "A8", "publisher": "American Geophysical Union", "pagerange": "6933-6938", "id_number": "CaltechAUTHORS:20140923-134523450", "issn": "0148-0227", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140923-134523450", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "EY-76-C-02-3074" }, { "agency": "NASA", "grant_number": "NGR 05-002-333" }, { "agency": "Caltech President's Fund" }, { "agency": "NSF", "grant_number": "PHY79-23638" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/JA086iA08p06933", "primary_object": { "basename": "jgra5759.pdf", "url": "https://authors.library.caltech.edu/records/2yacj-eyw53/files/jgra5759.pdf" }, "resource_type": "article", "pub_year": "1981", "author_list": "Haff, P. K.; Watson, C. C.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/5bq7r-hc359", "eprint_id": 49948, "eprint_status": "archive", "datestamp": "2023-08-22 02:41:34", "lastmod": "2023-10-17 22:23:49", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Allen-M-A", "name": { "family": "Allen", "given": "Mark" } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Waters-J-W", "name": { "family": "Waters", "given": "Joe W." } } ] }, "title": "Vertical transport and photochemistry in the terrestrial mesosphere and lower thermosphere (50\u2013120 km)", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1981 by the American Geophysical Union. Received July 24, 1980; revised December 18, 1980; accepted December 19, 1980.\n\nPaper number 80A1817.\n\nWe thank S. Deguchi, C. B. Farmer, D. O. Muhleman, H. Trinks, and W. J. Wilson for communicating their results\nprior to publication. We also acknowledge the helpful comments of J. Anderson, W. B. DeMore, P. A. Ekstrom, D. M. Hunten, M. M. Litvak, R. Stolarski, D. F. Strobel, R. T. Watson, and the referees. This research was supported by NASA grant NSG 2229 and JPL 49-649-20320-0-3270 to the California Institute of Technology Contribution 3273 of the Division of Geological and Planetary Sciences, California\nInstitute of Technology.\nThe Editor thanks P. H. G. Dickinson and J. E. Frederick for their\nassistance in evaluating this paper.\n\nPublished - jgra5603.pdf
", "abstract": "The coupled effects of kinetics, solar cycle flux variations and vertical transport on the distribution of long-lived hydrogen-carbon-oxygen compounds in the terrestrial mesosphere and lower thermosphere are studied using a one-dimensional aeronomy model. The calculations account for the important chemical reactions and use rocket measurements of the solar flux at solar minimum and maximum. Photodissociation rates appropriate for the mesosphere are determined with a spherical shell atmosphere formalism; detailed corrections for the O_2 Schumann-Runge bands and the temperature dependence of the CO_2 cross sections are used. Then an eddy diffusion profile is derived which gives agreement with the Aladdin 74 mass spectral measurements of atomic O, O_2, CO_2, and Ar in the lower thermosphere and observations of the O_3 minimum at \u223c80 km. The 115 GHz CO radio emission line computed for the CO mixing ratio profile predicted with the new eddy diffusion profile compares well with recent observations of W. J. Wilson. Differences between the calculated CO mixing ratio profile and previous theoretical and observational determinations are discussed. Our derived eddy diffusion profile has a sudden decrease at 92 km which is necessary to produce the atomic O peak at 98 km that appears in the Aladdin 74 measurements. This stagnant region apparently is a recurrent or persistent feature of the upper atmosphere since an atomic O peak around 98 km has been seen by different techniques in different seasons over several years. Slow eddy diffusion in the lower thermosphere through the homopause was also the conclusion of earlier Ar/N_2 rocket measurements studies. The analytic approach of this paper could be used in the future to monitor variations in middle atmosphere dynamics, if regularly conducted simultaneous observations of various groups of species were available.", "date": "1981-05-01", "date_type": "published", "publication": "Journal of Geophysical Research A", "volume": "86", "number": "A5", "publisher": "American Geophysical Union", "pagerange": "3617-3627", "id_number": "CaltechAUTHORS:20140923-133225043", "issn": "0148-0227", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140923-133225043", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NSG 2229" }, { "agency": "JPL", "grant_number": "49-649-20320-0-3270" } ] }, "other_numbering_system": { "items": [ { "id": "3273", "name": "Caltech Division of Geological and Planetary Sciences" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/JA086iA05p03617", "primary_object": { "basename": "jgra5603.pdf", "url": "https://authors.library.caltech.edu/records/5bq7r-hc359/files/jgra5603.pdf" }, "resource_type": "article", "pub_year": "1981", "author_list": "Allen, Mark; Yung, Yuk L.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/qda3j-xbp63", "eprint_id": 49203, "eprint_status": "archive", "datestamp": "2023-08-22 02:32:22", "lastmod": "2023-10-17 21:12:47", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Allen-M-A", "name": { "family": "Allen", "given": "Mark" } }, { "id": "Pinto-J-P", "name": { "family": "Pinto", "given": "Joseph P." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Titan: Aerosol photochemistry and variations related to the sunspot cycle", "ispublished": "pub", "full_text_status": "public", "keywords": "planets: atmospheres; planets: satellites; planets: Saturn; Sun: activity", "note": "\u00a9 1980 American Astronomical Society. Provided by the NASA Astrophysics Data System. Received 1980 June 9; accepted 1980 August 15. We thank W. A. Goddard III and R. C. Flagan for discussions on the mechanism of soot formation; F. S.\nRowland, H. Okabe, A. H. Laufer, and L. J. Stief for\ndiscussions on the kinetics of hydrocarbons; W. T. Huntress, Jr., and E. M. Purcell for discussions on the\nchemistry of the interstellar medium and interstellar\ngrains; D. F. Strobel and M. B. McElroy for sharing\nwith us their insight into the chemistry of Jovian\natmospheres; and D. M. Hunten and R. M. Goody for\ncritically reading our manuscript. This research is supported by NASA contract NSG 7376 under the Planetary\nAtmospheres Program. J. P. is an NAS NRC resident research associate.\n\nPublished - 1980ApJ___242L_125A.pdf
", "abstract": "A photochemical theory is proposed for producing complex polymers in a methane atmosphere. It is argued that the polyacetylenes (C_(2n)H_2) are the most likely precursor molecules for the formation of the stratospheric haze layer on Titan. The production of polyacetylenes involves a strong\npositive feedback, leading to more production of polyactylenes. The thermosphere of Titan may undergo substantial expansion and contraction over a solar cycle, with important consequences for the chemistry of the upper atmosphere.", "date": "1980-12-01", "date_type": "published", "publication": "Astrophysical Journal Letters", "volume": "242", "number": "2", "publisher": "American Astronomical Society", "pagerange": "L125-L128", "id_number": "CaltechAUTHORS:20140903-140202245", "issn": "2041-8205", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140903-140202245", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NSG 7376" } ] }, "other_numbering_system": { "items": [ { "id": "3436", "name": "Caltech Division of Geological and Planetary Sciences" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1086/183416", "primary_object": { "basename": "1980ApJ___242L_125A.pdf", "url": "https://authors.library.caltech.edu/records/qda3j-xbp63/files/1980ApJ___242L_125A.pdf" }, "resource_type": "article", "pub_year": "1980", "author_list": "Allen, Mark; Pinto, Joseph P.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/t2st2-85324", "eprint_id": 49495, "eprint_status": "archive", "datestamp": "2023-08-22 02:29:45", "lastmod": "2023-10-17 21:29:05", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Pinto-J-P", "name": { "family": "Pinto", "given": "Joseph P." } }, { "id": "Gladstone-G-R", "name": { "family": "Gladstone", "given": "G. Randall" } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk Ling" }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Photochemical Production of Formaldehyde in Earth's Primitive Atmosphere", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 1980 American Association for the Advancement of Science. \nReceived for publication 7 February 1980. Revision received 17 June 1980. One of us (J.P.P.) thanks J. C. G. Walker for\nmany helpful discussions. We also thank M. Allen, F. P. Fanale, G. L. Kok, C. B. Moore, J. S. Lewis, and J . J. Morgan for their useful comments. J.P.P. is a NASA National Research Council resident research associate. This work\nwas also supported in part by NASA contract NSG-7376 under the Planetary Atmospheres Program. Contribution 3357 of the Division of Geological and Planetary Sciences, California\nInstitute of Technology.", "abstract": "Formaldehyde could have been produced by photochemical reactions in Earth's primitive atmosphere, at a time when it consisted mainly of molecular nitrogen, water vapor, carbon dioxide, and trace amounts of molecular hydrogen and carbon monoxide. Removal of formaldehyde from the atmosphere by precipitation can provide a source of organic carbon to the oceans at the rate of 10^(11) moles per year. Subsequent reactions of formaldehyde in primeval aquatic environments would have implications for the abiotic synthesis of complex organic molecules and the origin of life.", "date": "1980-10-10", "date_type": "published", "publication": "Science", "volume": "210", "number": "4466", "publisher": "American Association for the Advancement of Science", "pagerange": "183-185", "id_number": "CaltechAUTHORS:20140909-105824380", "issn": "0036-8075", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140909-105824380", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NSG-7376" } ] }, "other_numbering_system": { "items": [ { "id": "3357", "name": "Caltech Division of Geological and Planetary Sciences" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1126/science.210.4466.183", "resource_type": "article", "pub_year": "1980", "author_list": "Pinto, Joseph P.; Gladstone, G. Randall; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/aksck-5ar90", "eprint_id": 49126, "eprint_status": "archive", "datestamp": "2023-08-22 02:28:29", "lastmod": "2023-10-17 21:09:23", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Pollack-J-B", "name": { "family": "Pollack", "given": "James B." } }, { "id": "Rages-K-A", "name": { "family": "Rages", "given": "Kathy" } }, { "id": "Toon-O-B", "name": { "family": "Toon", "given": "Owen B." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "On the relationship between secular brightness changes of Titan and solar variability", "ispublished": "pub", "full_text_status": "public", "note": "This paper is not subject to U.S. copyright. Published\nin 1980 by the American Geophysical Union.\n\nReceived June 16, 1980; accepted August 5, 1980. \n\nPaper number 80L1079.\n\nPublished - grl1402.pdf
", "abstract": "Titan's geometric albedo varied noticeably from 1972 to 1978, in phase with variations in solar activity [Lockwood and Thompson, 1979]. We carry out a series of radiative transfer and aerosol formation calculations in order to demonstrate the feasibility of the following scenario for these secular brightness changes: solar activity changes, especially in the UV output of the Sun, result in alterations to the mass production rate of aerosols in Titan's atmosphere, which lead to modifications of their microphysical properties. The latter, in turn, cause the albedo to vary. Current estimates of the change in the solar UV radiation below the dissociation limit of methane imply alterations to the mean radius of the aerosols over an 11-yr solar cycle that are consistent in sign and magnitude with those required to explain the observed secular brightness changes.", "date": "1980-10", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "7", "number": "10", "publisher": "American Geophysical Union", "pagerange": "829-832", "id_number": "CaltechAUTHORS:20140902-134158307", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140902-134158307", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/GL007i010p00829", "primary_object": { "basename": "grl1402.pdf", "url": "https://authors.library.caltech.edu/records/aksck-5ar90/files/grl1402.pdf" }, "resource_type": "article", "pub_year": "1980", "author_list": "Pollack, James B.; Rages, Kathy; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/0ak93-qnd37", "eprint_id": 49201, "eprint_status": "archive", "datestamp": "2023-08-22 02:24:02", "lastmod": "2023-10-17 21:12:40", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Strobel-D-F", "name": { "family": "Strobel", "given": "Darrell F." } } ] }, "title": "Hydrocarbon photochemistry and Lyman alpha albedo of Jupiter", "ispublished": "pub", "full_text_status": "public", "keywords": "molecular processes; planets: abundances; planets: Jupiter", "note": "\u00a9 1980 American Astronomical Society. Provided by the NASA Astrophysics Data System. Received 1979 December 6; accepted 1980 January 8. We thank A. L. Broadfoot and his team for\nproviding us with preliminary data, G. R. Gladstone, and W. Huntress for helpful discussion. We thank the referee D. M. Hunten for improving our paper in many ways. This research was supported by NASA contract NSG-7376 to the California Institute of Technology under the Planetary Atmosphere Program.\n\nPublished - 1980ApJ___239__395Y.pdf
", "abstract": "A combined study of hydrocarbon and atomic hydrogen photochemistry is made to calculate self-consistently the L\u0251 albedo of Jupiter. It is shown that the L\u0251 emissions observed by Voyagers I and II can be explained by resonance scattering of sunlight. Precipitation-of energetic particles\nfrom the magnetosphere can provide the large required source of atomic hydrogen, although the contribution of direct particle excitation to the disk-averaged brightness is insignificant. The variability of the L\u0251 brightness inferred from many observations in recent years is examined. The large difference in the brightness of the He 584 \u00c5 resonance line observed by Pioneer and Voyager is briefly discussed. Driving the photochemistry by solar ultraviolet radiation alone yields a maximum mixing ratio of C_2H_6 + C_2H_2 at 10^(-2) atm of about 4 x 10^(-6). The possibility of additional CH_4 dissociation from precipitation of magnetospheric particles is discussed. The\nphotochemistry of C_2H_2 and C_2H_3 is sufficiently uncertain not to permit accurate calculations of their densities and the ratio C_2H_6/C_2H_2.", "date": "1980-07-01", "date_type": "published", "publication": "Astrophysical Journal", "volume": "239", "number": "1", "publisher": "American Astronomical Society", "pagerange": "395-402", "id_number": "CaltechAUTHORS:20140903-134806600", "issn": "0004-637X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140903-134806600", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NSG-7376" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1086/158120", "primary_object": { "basename": "1980ApJ___239__395Y.pdf", "url": "https://authors.library.caltech.edu/records/0ak93-qnd37/files/1980ApJ___239__395Y.pdf" }, "resource_type": "article", "pub_year": "1980", "author_list": "Yung, Yuk L. and Strobel, Darrell F." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/dyx02-0rz98", "eprint_id": 1645, "eprint_status": "archive", "datestamp": "2023-08-22 02:20:25", "lastmod": "2023-10-13 22:55:14", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Pollack-J-B", "name": { "family": "Pollack", "given": "James B." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Origin and evolution of planetary atmospheres", "ispublished": "pub", "full_text_status": "public", "note": "\"Reprinted, with permission, from the Annual Review of Earth and Planetary Sciences, Volume 8 copyright 1980 by Annual Reviews, www.annualreviews.org\" \n\nWe are very grateful to Ray Reynolds and Brian Toon for their careful reading of this paper and their helpful suggestions.", "abstract": "Spacecraft and groundbased observations of the atmospheres of solar system objects have provided a definition of their present characteristics and have yielded clues about their past history. Table 1 presents a summary of our current knowledge of the atmospheric properties of all the planets, except Pluto, and several satellites. The masses of these atmospheres range from the very miniscule values for the Moon, Mercury, and Io, to the more substantial values for the Earth, Venus, Mars, and Titan, to the very large values for the giant planets, where the atmosphere constitutes a significant fraction of the total planetary mass. The compositions of these atmospheres encompass ones dominated by rare gases (the Moon and Mercury), ones containing highly oxidized compounds of carbon, nitrogen, and sulfur (the outer three terrestrial planets and Io), and ones with highly reduced gases (Titan and the giant planets). What factors account for this enormous diversity in properties?", "date": "1980-05-01", "date_type": "published", "publication": "Annual Review of Earth and Planetary Sciences", "volume": "8", "publisher": "Annual Review of Earth and Planetary Sciences", "pagerange": "425-487", "id_number": "CaltechAUTHORS:POLareps80", "issn": "0084-6597", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:POLareps80", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1146/annurev.ea.08.050180.002233", "primary_object": { "basename": "POLareps80.pdf", "url": "https://authors.library.caltech.edu/records/dyx02-0rz98/files/POLareps80.pdf" }, "resource_type": "article", "pub_year": "1980", "author_list": "Pollack, James B. and Yung, Yuk L." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/a0jsw-4b282", "eprint_id": 11818, "eprint_status": "archive", "datestamp": "2023-08-22 02:16:13", "lastmod": "2023-10-17 15:48:37", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Y. L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Pinto-J-P", "name": { "family": "Pinto", "given": "J. P." } }, { "id": "Watson-R-T", "name": { "family": "Watson", "given": "R. T." } }, { "id": "Sander-S-P", "name": { "family": "Sander", "given": "S. P." }, "orcid": "0000-0003-1424-3620" } ] }, "title": "Atmospheric Bromine and Ozone Perturbations in the Lower Stratosphere", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1980 American Meteorological Society. \n\n(Manuscript received May 4, 1979, in final form September 26, 1979) \n\nWe thank A.L. Lazrus and W.A. Sedlacek for permission to use their data prior to publication. We benefited from discussions with W.B. DeMore, H.B. Singh, J.S. Chang, S.C. Liu, N.D. Sze, J.A. Logan, S.C. Wofsy, M.T. Molina and F.S. Rowland. We appreciate the constructive criticisms given by the referees, P.J. Crutzen and R.J. Cicerone in their reviews of this paper. \n\nThis research was supported by NASA Grant NSG 2229 to the California Institute of Technology and NASA Grant NSG 5163 Scope M to Columbia University; this also represents one phase of NASA sponsored research carried out at the Jet Propulsion Laboratory under Contract NAS 7-100. \n\nContribution No. 3215 of the Division of Geological and Planetary Sciences, California Institute of Technology.\n\nPublished - YUNjas80.pdf
", "abstract": "The role of bromine compounds in the photochemistry of the natural and perturbed stratosphere has been reexamined using an expanded reaction scheme and the results of recent laboratory studies of several key reactions. The most important finding is that through the reaction BrO + CIO \u2192 Br + Cl + O2, there is a synergistic effect between bromine and chlorine which results in an efficient catalytic destruction of ozone in the lower stratosphere. One-dimensional photochemical model results indicate that BrO is the major bromine species throughout the stratosphere, followed by BrONO2, HBr, HOBr and Br. We show from the foregoing that bromine is more efficient than chlorine as a catalyst for destroying ozone, and discuss the implications for stratospheric ozone of possible future growth in the industrial and agricultural use of bromine. Bromine concentrations of 20 pptv (2 \u00d7 10^\u221211), as suggested by recent observations, can decrease the present-day integrated ozone column density by 2.4%, and can enhance ozone depletion from steady-state chlorofluoromethane release at 1973 rates by a factor of 1.1\u20131.2.", "date": "1980-02", "date_type": "published", "publication": "Journal of the Atmospheric Sciences", "volume": "37", "number": "2", "publisher": "American Meteorological Society", "pagerange": "339-353", "id_number": "CaltechAUTHORS:YUNjas80", "issn": "0022-4928", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:YUNjas80", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NSG 2229" }, { "agency": "NASA", "grant_number": "NSG 5163 Scope M" }, { "agency": "NASA", "grant_number": "NAS 7-100" } ] }, "other_numbering_system": { "items": [ { "id": "3215", "name": "Division of Geological and Planetary Sciences Contribution" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1175/1520-0469(1980)037<0339:ABAOPI>2.0.CO;2", "primary_object": { "basename": "YUNjas80.pdf", "url": "https://authors.library.caltech.edu/records/a0jsw-4b282/files/YUNjas80.pdf" }, "resource_type": "article", "pub_year": "1980", "author_list": "Yung, Y. L.; Pinto, J. P.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/d8e27-wk397", "eprint_id": 32657, "eprint_status": "archive", "datestamp": "2023-08-22 02:16:24", "lastmod": "2023-10-18 14:38:26", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Wang-W-C", "name": { "family": "Wang", "given": "Wei-Chyung" } }, { "id": "Pinto-J-P", "name": { "family": "Pinto", "given": "Joseph P." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk Ling" }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Climatic Effects Due to Halogenated Compounds in the Earth's Atmosphere", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1980 American Meteorological Society.\n\nManuscript received 4 June 1979, in final form 29 August 1979.\nWe thank N. D. Sze, R. T.\nWatson, A. Goldman, D. G. Murcray and J. E. Hansen\nfor useful discussion, and R. T. Watson, S. P.\nSander and A. A. Lacis for permission to use their\nresults prior to publication. During the course of this\nwork, Pinto was supported by NASA Grant NSG\n5163 Scope M to Columbia University. Yung's research\nwas supported by NASA Grant NSG 2229\nto the California Institute of Technology.\n\nPublished - WANjas80.pdf
", "abstract": "Using a one-dimensional radiative-convective model, we perform a sensitivity study of the effect of ozone depletion in the stratosphere on the surface temperature. There could be a cooling of the surface temperature by ~0.2 K due to chlorofluoromethane-induced ozone depletion at steady state (assuming 1973 release rates). This cooling reduces significantly the greenhouse effect due to the presence of chlorofluoromethanes. Carbon tetrafluoride has a strong \u03bd_3 band at 7.8 \u03bcm, and the atmospheric greenhouse effect is shown to be 0.07 and 0.12 K (ppbv)^(\u22121) with and without taking into account overlap with CH_4 and N_2O bands. At concentration higher than 1 ppbv, absorption by the \u03bd_3 band starts to saturate and the greenhouse effect becomes less efficient.", "date": "1980-02", "date_type": "published", "publication": "Journal of the Atmospheric Sciences", "volume": "37", "number": "2", "publisher": "American Meteorological Society", "pagerange": "333-338", "id_number": "CaltechAUTHORS:20120724-075448222", "issn": "0022-4928", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20120724-075448222", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NSG 5163 Scope M" }, { "agency": "NASA", "grant_number": "NSG 2229" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1175/1520-0469(1980)037<0333:CEDTHC>2.0.CO;2", "primary_object": { "basename": "WANjas80.pdf", "url": "https://authors.library.caltech.edu/records/d8e27-wk397/files/WANjas80.pdf" }, "resource_type": "article", "pub_year": "1980", "author_list": "Wang, Wei-Chyung; Pinto, Joseph P.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/dv865-k0n64", "eprint_id": 49982, "eprint_status": "archive", "datestamp": "2023-08-22 02:09:06", "lastmod": "2023-10-17 22:25:17", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Watson-R-T", "name": { "family": "Watson", "given": "R. T." } }, { "id": "Sander-S-P", "name": { "family": "Sander", "given": "S. P." }, "orcid": "0000-0003-1424-3620" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Y. L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Pressure and temperature dependence kinetics study of the NO + BrO \u2192 NO_2 + Br reaction. Implications for stratospheric bromine photochemistry", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 1979 American Chemical Society. Received May 21, 1979.\n\nWe thank J. Linke for his indispensable glass blowing services, G. Tennant and M. Patapoff for their expert assistance in constructing the experimental apparatus, and J. Pinto for use of the output of our one dimensional\nphotochemical model prior to publication. We benefited greatly from discussions with W. B. DeMore. This paper presents the results of one phase of research carried out at the Jet Propulsion Laboratory, California Institute of Technology, under Contract No. NAS7-100, sponsored by the National Aeronautics and Space Administration. Part of this work was supported by NASA Grant NSG 2229 to the California Institute of Technology.", "abstract": "The flash photolysis-ultraviolet absorption technique has been utilized to study the reactivity of nitric oxide\nwith BrO radicals over a wide range of pressure (100-700 torr) and temperature (224-398 K). Pseudo-first-order\nconditions were used in order to minimize complications caused by secondary kinetic processes. The reaction\nand its corresponding Arrhenius expression in units of cm^3 molecule^(-1) s^(-1) can be written \nNO + BrO \u2192 NO_2 + Br \u0394H\u00ba_298 = -17.0 kcal mol^(-1)\nk_1 = (1.28 \u00b1 0.23) x 10^(-11)exp((181 \u00b1 46)/T) (T = 224-398 K)\nThe results are compared with previous measurements, and atmospheric implications of the reaction are discussed.\nIt is shown that this reaction is important in controlling the ratios [BrO]/[Br] and [BrO]/[HBr] in the stratosphere\nbut that it does not affect the catalytic efficiency of BrO, in ozone destruction.", "date": "1979-11", "date_type": "published", "publication": "Journal of Physical Chemistry", "volume": "83", "number": "23", "publisher": "American Chemical Society", "pagerange": "2936-2944", "id_number": "CaltechAUTHORS:20140924-094540365", "issn": "0022-3654", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140924-094540365", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NAS7-100" }, { "agency": "NASA", "grant_number": "NSG 2229" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1021/j100486a002", "resource_type": "article", "pub_year": "1979", "author_list": "Watson, R. T.; Sander, S. P.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/3hazd-1ky37", "eprint_id": 49910, "eprint_status": "archive", "datestamp": "2023-09-15 04:50:51", "lastmod": "2023-10-23 21:10:40", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Y. L." }, "orcid": "0000-0002-4263-2562" }, { "id": "McElroy-M-B", "name": { "family": "McElroy", "given": "M. B." } } ] }, "title": "Fixation of Nitrogen in the Prebiotic Atmosphere", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 1979 American Association for the Advancement of Science.\n\nReceived 4 August 1978; revised 13 November 1978.\n\nWe thank S. C. Wofsy for helpful discussions.\nSupported by NSF contract NSF-ATM-75-22723 to Harvard University and NASA grant\nNSG 7376 to the California Institute of Technology.\nContribution 3109 of the Division of\nGeological and Planetary Sciences, California\nInstitute of Technology.", "abstract": "Reactions between nitrogen and water in the air surrounding lightning discharges can provide an important source of nitric oxide even under conditions where oxygen is a minor atmospheric constituent. Estimates are given for the associated source of soluble nitrite and nitrate. It is shown that lightning and subsequent atmospheric chemistry can provide a source of nitrate for the primitive ocean as large as 106 tons of nitrogen per year, sufficient to fill the ocean to its present level of nitrate in less than 10^6 years.", "date": "1979-03-09", "date_type": "published", "publication": "Science", "volume": "203", "number": "4384", "publisher": "American Association for the Advancement of Science", "pagerange": "1002-1004", "id_number": "CaltechAUTHORS:20140922-144610992", "issn": "0036-8075", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140922-144610992", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "ATM-75-22723" }, { "agency": "NASA", "grant_number": "NSG 7376" } ] }, "other_numbering_system": { "items": [ { "id": "3109", "name": "Caltech Division of Geological and Planetary Sciences" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1126/science.203.4384.1002", "resource_type": "article", "pub_year": "1979", "author_list": "Yung, Y. L. and McElroy, M. B." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/hdm0n-tsv44", "eprint_id": 48340, "eprint_status": "archive", "datestamp": "2023-08-22 01:56:48", "lastmod": "2023-10-17 18:43:29", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Strobel-D-F", "name": { "family": "Strobel", "given": "Darrell F." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "The Galilean satellites as a source of CO in the Jovian upper atmosphere", "ispublished": "pub", "full_text_status": "restricted", "note": "Copyright \u00a9 1979 Published by Elsevier Inc. \n\nReceived April 24, 1978; revised August 4, 1978. \n\nOne of us (Y.L.Y.) thanks Professor T. A.\nTombrello and J. Griffith for giving us the LSS\ncomputer code for calculating projected ion ranges.\nWe are indebted to Dr. D. J. Bogan for helpful\ndiscussions. This research was supported by the\nPlanetary Atmospheres program of NASA under\ngrant NSG-7376.", "abstract": "Material from the Galilean satellites of Jupiter ejected by energetic particles in the Jovian magnetosphere may provide large sources of oxygen to the parent planet. Formation of a CO molecule is the ultimate fate of an oxygen atom in the upper Jovian atmosphere. This high altitude source of CO supports Beer and Taylor's (1978, Astrophys. J. 221) observations and analysis, provided that the globally averaged O atom input flux is \u223c10^7 cm^(\u22122) sec^(\u22121) and the eddy diffusion coefficient at the tropopause is \u223c10^3 cm^2 sec^(\u22121). Implications for the possible presence of other atoms and molecules derived from the satellites are discussed.", "date": "1979-01", "date_type": "published", "publication": "Icarus", "volume": "37", "number": "1", "publisher": "Elsevier", "pagerange": "256-263", "id_number": "CaltechAUTHORS:20140811-145736404", "issn": "0019-1035", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140811-145736404", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NSG-7376" } ] }, "other_numbering_system": { "items": [ { "id": "3067", "name": "Caltech Division of Geological and Planetary Sciences" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/0019-1035(79)90130-1", "resource_type": "article", "pub_year": "1979", "author_list": "Strobel, Darrell F. and Yung, Yuk L." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/9dn3c-17w74", "eprint_id": 10612, "eprint_status": "archive", "datestamp": "2023-08-22 01:54:01", "lastmod": "2023-10-16 22:58:07", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Variational principle for scattering of light by dielectric particles", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 Copyright 1978 Optical Society of America. \n\nReceived 4 August 1978. \n\nThe author thanks E.M. Purcell, and Tony Chan for valuable discussions, C.R. Pennypacker and P.R. Shapiro for giving him their computing codes, A.A. Lacis for a copy of Mie program, and Y.S. Yung, C.K. Shum, and H.K. Wong for programming assistance. The author also thanks the referee for a number of helpful suggestions. This research was supported by NASA NSG-7376. \n\nThis Letter represents Contribution 3015 of the Division of Geological and Planetary Sciences, California Institute of Technology.", "abstract": "We exploit two fundamental properties of the dipole interaction matrix A (symmetry with respect to reversal of incident beam direction and interchange of any pair of dipoles) to construct two functionals. The connection with the minimum energy theorem and cross section suggests that our numerical algorithm will search for a physical quantity, and hence it would be efficient and stable. In this Letter we have made the crudest use of the variational principle. The practical limit for the current version of our numerical scheme is a dipole array (with fourfold symmetry) of order N ~10,000 atoms. Since the phase difference between neighboring atoms should be \u22641/3 rad for reliable results, this limits the scattering parameter 2\u03c0a/\u03bb to \u226410. The storage required is ~20N real numbers, and the time is ~1x10^-6 N^2 min on a CDC 7600. Note that the main advantage with the current method is that we do not need to store the A matrix with order N^2 elements.", "date": "1978-12-01", "date_type": "published", "publication": "Applied Optics", "volume": "17", "number": "23", "publisher": "Optical Society of America", "pagerange": "3707-3709", "id_number": "CaltechAUTHORS:YUNao78", "issn": "0003-6935", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:YUNao78", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "primary_object": { "basename": "YUNao78.pdf", "url": "https://authors.library.caltech.edu/records/9dn3c-17w74/files/YUNao78.pdf" }, "resource_type": "article", "pub_year": "1978", "author_list": "Yung, Yuk L." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/4esvm-krh72", "eprint_id": 49892, "eprint_status": "archive", "datestamp": "2023-08-22 01:46:22", "lastmod": "2023-10-17 22:17:52", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Y. L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Pinto-J-P", "name": { "family": "Pinto", "given": "J. P." } } ] }, "title": "Primitive atmosphere and implications for the formation of channels on Mars", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 1978 Macmillan Journals Ltd.\n\nReceived 6 February; accepted 3 May 1978.\n\nY.L.Y. thanks Professor M. B. McElroy for valuable insights\non atmospheric evolution, hydrogen escape and isotopic ratio\nand J.B. Pollack and O. B. Toon for discussion of present and\npast climates on Mars. This research was supported by Ames\nResearch Center under NASA contract NSG-2283. J.P.P.\nacknowledges support by NASA grant NSG-5163 to\nColumbia.", "abstract": "The channels on Mars suggest that a flowing fluid has been present on the surface of the planet. It seems natural to assume that this fluid was water. The major difficulty, however, is that water freezes in climatic conditions like those now on Mars. It has been suggested that primitive Mars had a reducing atmosphere, composed mainly of methane. Such an atmosphere, as we show here, could be polymerised by solar ultraviolet radiation to produce higher hydrocarbons. These compounds are low viscosity liquids at today's temperature on Mars, and could contribute to the formation of channels.", "date": "1978-06-29", "date_type": "published", "publication": "Nature", "volume": "273", "number": "5665", "publisher": "Nature Publishing Group", "pagerange": "730-732", "id_number": "CaltechAUTHORS:20140922-102041396", "issn": "0028-0836", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140922-102041396", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NSG-2283" }, { "agency": "NASA", "grant_number": "NSG-5163" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1038/273730a0", "resource_type": "article", "pub_year": "1978", "author_list": "Yung, Y. L. and Pinto, J. P." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/dpjtw-n2t97", "eprint_id": 49903, "eprint_status": "archive", "datestamp": "2023-08-22 01:36:34", "lastmod": "2023-10-17 22:18:16", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Atreya-S-K", "name": { "family": "Atreya", "given": "S. K." }, "orcid": "0000-0002-1972-1815" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Y. L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Donahue-T-M", "name": { "family": "Donahue", "given": "T. M." } }, { "id": "Barker-E-S", "name": { "family": "Barker", "given": "E. S." } } ] }, "title": "Search for Jovian auroral hot spots", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1977 American Astronomical Society.\n\nProvided by the NASA Astrophysics Data System.\n\nPartial support provided by NASA grant NSG-5139\nand AURA subcontract 86303 (NASA/JPL contract\n7-100) is gratefully acknowledged.\n\nPublished - 1977ApJ___218L__83A.pdf
", "abstract": "Auroral emission originating at the foot of the Io-associated flux tube at Jupiter has been detected with a high-resolution spectrometer/telescope on board the Orbiting Astronomical Observatory Copernicus. The emission intensity at Ly-alpha is found to be greater than 100 kR, and the emission is located at zenographic latitudes greater than 65\u00b0.", "date": "1977-12-01", "date_type": "published", "publication": "Astrophysical Journal Letters", "volume": "218", "number": "2", "publisher": "American Astronomical Society", "pagerange": "L83-L87", "id_number": "CaltechAUTHORS:20140922-130207209", "issn": "2041-8205", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140922-130207209", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NSG-5139" }, { "agency": "Association of Universities for Research in Astronomy (AURA)", "grant_number": "86303" }, { "agency": "NASA", "grant_number": "NAS 7-100" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1086/182581", "primary_object": { "basename": "1977ApJ___218L__83A.pdf", "url": "https://authors.library.caltech.edu/records/dpjtw-n2t97/files/1977ApJ___218L__83A.pdf" }, "resource_type": "article", "pub_year": "1977", "author_list": "Atreya, S. K.; Yung, Y. L.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/992j6-86b36", "eprint_id": 52774, "eprint_status": "archive", "datestamp": "2023-08-22 01:34:56", "lastmod": "2023-10-18 21:04:22", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Broadfoot-A-L", "name": { "family": "Broadfoot", "given": "A. L." } }, { "id": "Sandel-B-R", "name": { "family": "Sandel", "given": "B. R." } }, { "id": "Shemansky-D-E", "name": { "family": "Shemansky", "given": "D. E." }, "orcid": "0000-0001-7168-871X" }, { "id": "Atreya-S-K", "name": { "family": "Atreya", "given": "S. K." }, "orcid": "0000-0002-1972-1815" }, { "id": "Donahue-T-M", "name": { "family": "Donahue", "given": "T. M." } }, { "id": "Moos-H-W", "name": { "family": "Moos", "given": "H. W." } }, { "id": "Bertaux-J-L", "name": { "family": "Bertaux", "given": "J. L." } }, { "id": "Blamont-J-E", "name": { "family": "Blamont", "given": "J. E." } }, { "id": "Ajello-J-M", "name": { "family": "Ajello", "given": "J. M." } }, { "id": "Strobel-D-F", "name": { "family": "Strobel", "given": "D. F." } }, { "id": "McConnell-J-C", "name": { "family": "McConnell", "given": "J. C." } }, { "id": "Dalgarno-A", "name": { "family": "Dalgarno", "given": "A." } }, { "id": "Goody-R-M", "name": { "family": "Goody", "given": "R." } }, { "id": "McElroy-M-B", "name": { "family": "McElroy", "given": "M. B." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Y. L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Ultraviolet spectrometer experiment for the Voyager mission", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 1977 by D. Reidel Publishing Company.\n\nReceived 24 May, 1977.\n\nThe Kitt Peak National Observatory is operated by the Association of Universities\nfor Research in Astronomy, Inc., under contract with the National Science Foundation.\nThis work was supported by the Jet Propulsion Laboratory, California Institute\nof Technology, under NASA contract NAS 7-100.", "abstract": "The Voyager Ultraviolet Spectrometer (UVS) is an objective grating spectrometer covering the wavelength range of 500\u20131700 \u00c5 with 10 \u00c5 resolution. Its primary goal is the determination of the composition and structure of the atmospheres of Jupiter, Saturn, Uranus and several of their satellites. The capability for two very different observational modes have been combined in a single instrument. Observations in the airglow mode measure radiation from the atmosphere due to resonant scattering of the solar flux or energetic particle bombardment, and the occultation mode provides measurements of the atmospheric extinction of solar or stellar radiation as the spacecraft enters the shadow zone behind the target. In addition to the primary goal of the solar system atmospheric measurements, the UVS is expected to make valuable contributions to stellar astronomy at wavelengths below 1000 \u00c5.", "date": "1977-11", "date_type": "published", "publication": "Space Science Reviews", "volume": "21", "number": "2", "publisher": "Springer", "pagerange": "183-205", "id_number": "CaltechAUTHORS:20141212-140537933", "issn": "0038-6308", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20141212-140537933", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NAS 7-100" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "resource_type": "article", "pub_year": "1977", "author_list": "Broadfoot, A. L.; Sandel, B. R.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/7v7nn-5te53", "eprint_id": 49267, "eprint_status": "archive", "datestamp": "2023-08-22 01:33:33", "lastmod": "2023-10-17 21:15:50", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "McElroy-M-B", "name": { "family": "McElroy", "given": "Michael B." } }, { "id": "Kong-Ten-Ying", "name": { "family": "Kong", "given": "Ten Ying" } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk Ling" }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Photochemistry and evolution of Mars' atmosphere: A Viking perspective", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1977 by the American Geophysical Union. \n\nReceived April 21, 1977; revised June 8, 1977; accepted June 8, 1977. \n\nPaper number 7S0558. \n\nThis work was supported by the National Aeronautics and Space Administration under grant NAS-1-10492 and by the National Science Foundation under grant NSF-ATM75-22723, both to Harvard University. We are indebted to E. Anders, T. Owen, and S. Wofsy for illuminating discussions.\n\nPublished - jgr6722.pdf
", "abstract": "Viking measurements of the Martian upper atmosphere indicate thermospheric temperatures below 200\u00b0K, temperatures much colder than those implied by remote sensing experiments on Mariner 6, 7, and 9 and Mars 3. The variability in thermospheric temperature may reflect an important dynamical coupling of upper and lower regions of the Martian atmosphere. Absorption of extreme ultraviolet solar radiation can account for observed features of the ionosphere and provides an important source of fast N and O atoms which may escape the planet's gravitational field. Isotopic measurements of oxygen and nitrogen impose useful constraints on models for planetary evolution. It appears that the abundance of N_2 in Mars' past atmosphere may have exceeded the abundance of CO_2 in the present atmosphere and that the planet also has copious sources of H_2O. The planet acquired its nitrogen atmosphere early in its history. The degassing rate for nitrogen in the present epoch must be less than the time-averaged degassing rate by at least a factor of 20.", "date": "1977-09-30", "date_type": "published", "publication": "Journal of Geophysical Research", "volume": "82", "number": "28", "publisher": "American Geophysical Union", "pagerange": "4379-4388", "id_number": "CaltechAUTHORS:20140905-083121119", "issn": "0148-0227", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140905-083121119", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NAS-1-10492" }, { "agency": "NSF", "grant_number": "ATM-75-22723" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/JS082i028p04379", "primary_object": { "basename": "jgr6722.pdf", "url": "https://authors.library.caltech.edu/records/7v7nn-5te53/files/jgr6722.pdf" }, "resource_type": "article", "pub_year": "1977", "author_list": "McElroy, Michael B.; Kong, Ten Ying; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/hwxcb-0r694", "eprint_id": 49897, "eprint_status": "archive", "datestamp": "2023-08-22 01:24:19", "lastmod": "2023-10-17 22:18:01", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "McElroy-M-B", "name": { "family": "McElroy", "given": "M. B." } }, { "id": "Wofsy-S-C", "name": { "family": "Wofsy", "given": "S. C." }, "orcid": "0000-0002-3990-6737" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Y. L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "The Nitrogen Cycle: Perturbations Due to Man and Their Impact on Atmospheric N_2O and O_3", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 1977 The Royal Society.\n\nPublished 21 March 1977.\n\nThe research described here was supported in part by the Atmospheric Sciences Section of the National Science Foundation, in part by NASA Grant NSG-2031 to Harvard University, with additional support from Queen's University provided by a grant from the National Environment Research Council.", "abstract": "Features of the global cycle of fixed nitrogen are reviewed with an emphasis on perturbations due to man. It is argued that agricultural practices and combustion may lead to an increase in the concentration of atmospheric N2_O with consequent effects on O_3. The level of O_3 may drop by about 20% over the next 100 years if world population and the demand for food should continue to grow at anything like rates which prevailed in the recent past. Uncertainties in the model are highlighted and note is taken of areas where there is need for additional data.", "date": "1977-03-21", "date_type": "published", "publication": "Philosophical Transactions of the Royal Society of London. Series B, Biological Sciences", "volume": "277", "number": "954", "publisher": "Royal Society of London", "pagerange": "159-181", "id_number": "CaltechAUTHORS:20140922-104156512", "issn": "0962-8436", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140922-104156512", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF" }, { "agency": "NASA", "grant_number": "NSG-2031" }, { "agency": "National Environment Research Council (NERC)" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1098/rstb.1977.0009", "resource_type": "article", "pub_year": "1977", "author_list": "McElroy, M. B.; Wofsy, S. C.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/sh7fc-r9j92", "eprint_id": 48323, "eprint_status": "archive", "datestamp": "2023-08-22 01:20:11", "lastmod": "2023-10-17 18:42:21", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk Ling" }, "orcid": "0000-0002-4263-2562" }, { "id": "Strobel-D-F", "name": { "family": "Strobel", "given": "Darrell F." } }, { "id": "Kong-Ten-Ying", "name": { "family": "Kong", "given": "Ten Ying" } }, { "id": "McElroy-M-B", "name": { "family": "McElroy", "given": "Michael B." } } ] }, "title": "Photochemistry of nitrogen in the Martian atmosphere", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 1977 Elsevier Inc. \n\nReceived September 14, 1976. \n\nThis research was supported by the National Science Foundation and by the National Aeronautics and Space Administration under Grants NSF-ATM-75-22723 and NAS-1-10492 to Harvard University. One of us (D.F.S.) acknowledges support from the Kitt Peak National Observatory, where he was employed during an earlier phase of this study. Kitt Peak is operated by AURA under contract to the National Science Foundation. The work was completed at the California Institute of Technology, where three of us (Y.L.Y., T.Y.K., and M.B.M.) were guests of the Division of Geological and Planetary Sciences. We wish to thank Professor B. Kamb and the staff of the Division for their hospitality.", "abstract": "Models are developed for the photochemistry of a CO_2-H_2O-N_2 atmosphere on Mars and estimates are given for the concentrations of N, NO, NO_2, NO_3, N_2O_5, HNO_2, HNO_3, and N_2O as a function of altitude. Nitric oxide is the most abundant form of odd nitrogen, present with a mixing ratio relative to CO_2 of order 10^(\u22128). Deposition rates for nitrite and nitrate minerals could be as large as 3\u00d7 10^5 N equivalent atoms cm^(\u22122) sec^(\u22121) under present conditions and may have been higher in the past.", "date": "1977-01", "date_type": "published", "publication": "Icarus", "volume": "30", "number": "1", "publisher": "Elsevier", "pagerange": "26-41", "id_number": "CaltechAUTHORS:20140811-133215122", "issn": "0019-1035", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140811-133215122", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "ATM-75-22723" }, { "agency": "NASA", "grant_number": "NAS-1-10492" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/0019-1035(77)90118-X", "resource_type": "article", "pub_year": "1977", "author_list": "Yung, Yuk Ling; Strobel, Darrell F.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/n0x4t-xft58", "eprint_id": 48330, "eprint_status": "archive", "datestamp": "2023-08-22 01:20:19", "lastmod": "2023-10-17 18:42:50", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Y. L." }, "orcid": "0000-0002-4263-2562" }, { "id": "McElroy-M-B", "name": { "family": "McElroy", "given": "M. B." } } ] }, "title": "Stability of an oxygen atmosphere on Ganymede", "ispublished": "pub", "full_text_status": "restricted", "note": "Copyright \u00a9 1977 Published by Elsevier Inc. \n\nReceived September 14, 1976. \n\nWe are indebted to D. L. Matson, who provided\na thermal model used here to estimate the mean\nvalue for the surface pressure of water vapor on\nGanymede. This research was supported by the\nAtmospheric Sciences Section of the National Science\nFoundation under Contract NSF-ATM-75-22723,\nand by AURA Contract 802-73, both to Harvard\nUniversity.", "abstract": "Photolysis of water and subsequent escape of hydrogen can give rise to an oxygen atmosphere on Ganymede. Growth of the atmosphere may be limited by escape of fast oxygen atoms formed by photodissociation of O_2. Escape of oxygen and hydrogen in an equilibrium configuration should balance net evaporation of water from the satellite's surface and the partial pressure of atmospheric O_2 could be as high as 10^(\u22123) mbar. Ganymede should have lost an appreciable quantity of water over geologic time, enough to have coated the surface of the satellite with ice to a depth of about 2 m. An oxygen atmosphere with similar properties might be expected to occur also on Callisto.", "date": "1977-01", "date_type": "published", "publication": "Icarus", "volume": "30", "number": "1", "publisher": "Elsevier", "pagerange": "97-103", "id_number": "CaltechAUTHORS:20140811-140109273", "issn": "0019-1035", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140811-140109273", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "ATM-75-22723" }, { "agency": "AURA", "grant_number": "802-73" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/0019-1035(77)90124-5", "resource_type": "article", "pub_year": "1977", "author_list": "Yung, Y. L. and McElroy, M. B." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/cggrg-r3112", "eprint_id": 49492, "eprint_status": "archive", "datestamp": "2023-08-22 01:18:06", "lastmod": "2023-10-17 21:28:56", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "McElroy-M-B", "name": { "family": "McElroy", "given": "M. B." } }, { "id": "Kong-Ten-Ying", "name": { "family": "Kong", "given": "T. Y." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Y. L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Nier-A-O", "name": { "family": "Nier", "given": "A. O." } } ] }, "title": "Composition and Structure of the Martian Upper Atmosphere: Analysis of Results from Viking", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 1976 American Association for the Advancement of Science. \n\nReceived 12 November 1976. \n\nWork at the University of Minnesota and at Harvard University was supported under NASA contracts NAS-1-9697 and NAS-1-10492, respectively.", "abstract": "Densities for carbon dioxide measured by the upper atmospheric mass spectrometers on Viking 1 and Viking 2 are analyzed to yield height profiles for the temperature of the martian atmosphere between 120 and 200 kilometers. Densities for nitrogen and argon are used to derive vertical profiles for the eddy diffusion coefficient over the same height range. The upper atmosphere of Mars is surprisingly cold with average temperatures for both Viking 1 and Viking 2 of less than 200\u00b0K, and there is significant vertical structure. Model calculations are presented and shown to be in good agreement with measured concentrations of carbon monoxide, oxygen, and nitric oxide.", "date": "1976-12-17", "date_type": "published", "publication": "Science", "volume": "194", "number": "4271", "publisher": "American Association for the Advancement of Science", "pagerange": "1295-1298", "id_number": "CaltechAUTHORS:20140909-101158778", "issn": "0036-8075", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140909-101158778", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NAS-1-9697" }, { "agency": "NASA", "grant_number": "NAS-1-10492" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1126/science.194.4271.1295", "resource_type": "article", "pub_year": "1976", "author_list": "McElroy, M. B.; Kong, T. Y.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/je788-xh678", "eprint_id": 48348, "eprint_status": "archive", "datestamp": "2023-08-22 01:16:54", "lastmod": "2023-10-17 18:44:05", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "McElroy-M-B", "name": { "family": "McElroy", "given": "Michael B." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk Ling" }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Oxygen isotopes in the Martian atmosphere: Implications for the evolution of volatiles", "ispublished": "pub", "full_text_status": "restricted", "note": "Copyright \u00a9 1976 Published by Elsevier Ltd. \n\nReceived 4 July 1976 by special delivery.\n\nWe wish to thank T. Y. Kong for\nimportant discussions on importance of heterogeneous\nprocesses at the Martian surface. The paper was written\nwhile the authors were guests of the Department of\nApplied Mathematics and Theoretical Physics, Queen's\nUniversity, Belfast We wish to acknowledge out appreciation\nto Professor P. G. Burke and the staff of the Department\nfor their hospitality. \n\nThe work in this paper was supported by the Atmospheric\nSciences Section of the National Science Foundation,\nunder grant #NSF-ATM-75-22723, and by the National\nAeronautics and Space Administration under grant\n#NAS-1-10492, both to Harvard University.", "abstract": "Non-thermal escape of oxygen by recombination of exospheric O_2^+ combined with diffusive separation of gases at lower altitude provides a mechanism through which the Martian atmosphere may be enriched in ^(18)O relative to ^(16)O. Measurement of the abundance of ^(18)O relative to ^(16)O together with a determination of the turbopause may be used to develop important constraints on the history of Martian volatiles. Models for the interpretation of these data are developed and discussed in light of present information.", "date": "1976-12", "date_type": "published", "publication": "Planetary and Space Science", "volume": "24", "number": "12", "publisher": "Elsevier", "pagerange": "1107-1113", "id_number": "CaltechAUTHORS:20140811-151619695", "issn": "0032-0633", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140811-151619695", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "ATM-75-22723" }, { "agency": "NASA", "grant_number": "NAS-1-10492" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/0032-0633(76)90148-3", "resource_type": "article", "pub_year": "1976", "author_list": "McElroy, Michael B. and Yung, Yuk Ling" }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/qbyqc-gjy40", "eprint_id": 47401, "eprint_status": "archive", "datestamp": "2023-08-22 01:16:25", "lastmod": "2023-10-26 20:34:01", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Wang-W-C", "name": { "family": "Wang", "given": "W. C." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Y. L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Lacis-A-A", "name": { "family": "Lacis", "given": "A. A." } }, { "id": "Mo-T", "name": { "family": "Mo", "given": "T." } }, { "id": "Hansen-J-E", "name": { "family": "Hansen", "given": "J. E." } } ] }, "title": "Greenhouse Effects due to Man-Made Perturbations of Trace Gases", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 1976 American Association for the Advancement of Science.\n\nWe thank R. Jastrow for pointing out the paper\nby Eddy (31), which led to the computation\nreported in (30). We also would like to thank\nP. Varanasi, F. W. Taylor, and A. D. Jones\nfor data supplied prior to publication, and V.\nRamanathan, W. B. Pearson, B. Gay, and G.\nOrton for useful information.", "abstract": "Nitrous oxide, methane, ammonia, and a number of other trace constituents in the earth's atmosphere have infrared absorption bands in the spectral region 7 to 14 \u00b5m and contribute to the atmospheric greenhouse effect. The concentrations of these trace gases may undergo substantial changes because of man's activities. Extensive use of chemical fertilizers and combustion of fossil fuels may perturb the nitrogen cycle, leading to increases in atmospheric N_2O, and the same perturbing processes may increase the amounts of atmospheric CH_4 and NH_3. We use a one-dimensional radiative-convective model for the atmospheric thermal structure to compute the change in the surface temperature of the earth for large assumed increases in the trace gas concentrations; doubling the N_2O, CH_4, and NH_3 concentrations is found to cause additive increases in the surface temperature of 0.7\u00b0, 0.3\u00b0, and 0.1\u00b0K, respectively. These systematic effects on the earth's radiation budget would have substantial climatic significance. It is therefore important that the abundances of these trace gases be accurately monitored to determine the actual trends of their concentrations.", "date": "1976-11-12", "date_type": "published", "publication": "Science", "volume": "194", "number": "4266", "publisher": "American Association for the Advancement of Science", "pagerange": "685-690", "id_number": "CaltechAUTHORS:20140722-132442437", "issn": "0036-8075", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140722-132442437", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1126/science.194.4266.685", "resource_type": "article", "pub_year": "1976", "author_list": "Wang, W. C.; Yung, Y. L.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/cy6qd-mnk04", "eprint_id": 49891, "eprint_status": "archive", "datestamp": "2023-08-22 01:15:30", "lastmod": "2023-10-17 22:17:46", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "McElroy-M-B", "name": { "family": "McElroy", "given": "Michael B." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk Ling" }, "orcid": "0000-0002-4263-2562" }, { "id": "Nier-A-O", "name": { "family": "Nier", "given": "Alfred O." } } ] }, "title": "Isotopic Composition of Nitrogen: Implications for the Past History of Mars' Atmosphere", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 1976 American Association for the Advancement of Science.\n\nReceived 2 September 1976.\n\nSupported by NASA contracts NAS-1-9697 and\nNAS-1-10492 to the University of Minnesota\nand Harvard University, respectively.", "abstract": "Models are presented for the past history of nitrogen on Mars based on Viking measurements showing that the atmosphere is enriched in ^(15)N. The enrichment is attributed to selective escape, with fast atoms formed in the exosphere by electron impact dissociation of N_2 and by dissociative recombination of N_2+. The initial partial pressure of N_2 should have been at least as large as several millibars and could have been as large as 30 millibars if surface processes were to represent an important sink for atmospheric HNO_2 and HNO_3.", "date": "1976-10-01", "date_type": "published", "publication": "Science", "volume": "194", "number": "4260", "publisher": "American Association for the Advancement of Science", "pagerange": "70-72", "id_number": "CaltechAUTHORS:20140922-101352569", "issn": "0036-8075", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140922-101352569", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NAS-1-9697" }, { "agency": "NASA", "grant_number": "NAS-1-10492" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1126/science.194.4260.70", "resource_type": "article", "pub_year": "1976", "author_list": "McElroy, Michael B.; Yung, Yuk Ling; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/e7qtr-c1m91", "eprint_id": 47371, "eprint_status": "archive", "datestamp": "2023-08-22 01:15:22", "lastmod": "2023-10-26 20:32:18", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Nier-A-O", "name": { "family": "Nier", "given": "Alfred O." } }, { "id": "McElroy-M-B", "name": { "family": "McElroy", "given": "Michael B." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk Ling" }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Isotopic Composition of the Martian Atmosphere", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 1976 American Association for the Advancement of Science.\n\nReceived 2 September 1976.\n\nWork at the University of Minnesota and at\nHarvard University was supported by NASA\nunder contracts NAS-1-9697 and NAS-1-10492,\nrespectively. A.O.N. is indebted to Ward Johnson\nfor help in making computations.", "abstract": "Results from the neutral mass spectrometer carried on the aeroshell of\nViking 1 show evidence for NO in the upper atmosphere of Mars and indicate that the\nisotopic composition of carbon and oxygen is similar to that of Earth. Mars is enriched\nin ^(15)N relative to Earth by about 75 percent, a consequence of escape that\nimplies an initial abundance of nitrogen equivalent to a partial pressure of at least 2\nmillibars. The initial abundance of oxygen present either as CO_2 or H_2O must be\nequivalent to an exchangeable atmospheric pressure of at least 2 bars in order to inhibit\nescape-related enrichment of ^(18)O.", "date": "1976-10-01", "date_type": "published", "publication": "Science", "volume": "194", "number": "4260", "publisher": "American Association for the Advancement of Science", "pagerange": "68-70", "id_number": "CaltechAUTHORS:20140721-141309854", "issn": "0036-8075", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140721-141309854", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NAS-1-9697" }, { "agency": "NASA", "grant_number": "NAS-1-10492" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1126/science.194.4260.68", "resource_type": "article", "pub_year": "1976", "author_list": "Nier, Alfred O.; McElroy, Michael B.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/hd3t8-rbs58", "eprint_id": 49981, "eprint_status": "archive", "datestamp": "2023-08-23 16:56:56", "lastmod": "2023-10-17 22:25:12", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Y. L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Wang-W-C", "name": { "family": "Wang", "given": "W. C." } }, { "id": "Lacis-A-A", "name": { "family": "Lacis", "given": "A. A." } } ] }, "title": "Greenhouse effect due to atmospheric nitrous oxide", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1976 by the American Geophysical Union. Received August 11, 1976; accepted August 27, 1976. Article first published online: 7 December 2012. \n\nWe thank M.B. McElroy, S.C. Hansen, and T. Mo for permission to use some of their results prior to publication. The work is partially supported by NASA Grant NSG-2031. Part of this research was done while one of us (Y.L.Y) was visiting the Division of Geological and Planetary Sciences at California Institute of Technology, and he would like to thank Professor B. Kamb for the hospitality of the department during his visit.\n\nPublished - grl429.pdf
", "abstract": "The greenhouse effect due to nitrous oxide in the present atmosphere is about 0.8\u00b0K. Increase in atmospheric N_2O due to perturbation of the nitrogen cycle by man may lead to an increase in surface temperature as large as 0.5\u00b0K by 2025, or 1.0\u00b0K by 2100. Other climatic effects of N_2O are briefly discussed.", "date": "1976-10", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "3", "number": "10", "publisher": "American Geophysical Union", "pagerange": "619-621", "id_number": "CaltechAUTHORS:20140924-093410370", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140924-093410370", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NSG-2031" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/GL003i010p00619", "primary_object": { "basename": "grl429.pdf", "url": "https://authors.library.caltech.edu/records/hd3t8-rbs58/files/grl429.pdf" }, "resource_type": "article", "pub_year": "1976", "author_list": "Yung, Y. L.; Wang, W. C.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/rz0bz-r4263", "eprint_id": 48339, "eprint_status": "archive", "datestamp": "2023-08-22 01:12:54", "lastmod": "2023-10-17 18:43:27", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "A numerical method for calculating the mean intensity in an inhomogeneous Rayleigh scattering atmosphere", "ispublished": "pub", "full_text_status": "restricted", "note": "Copyright \u00a9 1976 Published by Elsevier B.V. \n\nReceived 8 January 1976.\n\nI wish to thank Prof. R. M. GOODY for first suggesting the variational approach to radiative transfer\nproblems to me and for his continued guidance, and N. D. SZE for sharing his mathematical insight with me. I am grateful to\nS. C. WOFSY and Prof. M. B. MCELROY for helpful discussions and criticism. \n\nThis research was supported by the National Science Foundation under Grant DES 72-01472 A03 and by the National\nAeronautics and Space Administration under Grant NAS 523 199 to Harvard University.", "abstract": "We describe a method for calculating directly the mean integrated intensity in an inhomogeneous Rayleigh scattering atmosphere using a combined variational and iterative technique. This method is particularly useful for computing dissociation rates in aeronomical problems. Simple semi-analytic expressions are derived.", "date": "1976-09", "date_type": "published", "publication": "Journal of Quantitative Spectroscopy and Radiative Transfer", "volume": "16", "number": "9", "publisher": "Elsevier", "pagerange": "755-761", "id_number": "CaltechAUTHORS:20140811-145736301", "issn": "0022-4073", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140811-145736301", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "DES 72-01472 A03" }, { "agency": "NASA", "grant_number": "NAS 523 199" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/0022-4073(76)90003-0", "resource_type": "article", "pub_year": "1976", "author_list": "Yung, Yuk L." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/5h68b-7e953", "eprint_id": 48328, "eprint_status": "archive", "datestamp": "2023-08-22 01:12:45", "lastmod": "2023-10-17 18:42:44", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Goody-R-M", "name": { "family": "Goody", "given": "Richard M." } } ] }, "title": "Photometric properties of the surface of Io and their influence on line formation in the atmosphere", "ispublished": "pub", "full_text_status": "restricted", "note": "Copyright \u00a9 1976 Published by Elsevier Inc. \n\nReceived December 11, 1975; revised January 28, 1976. \n\nWe wish to acknowledge support under Grant\nDES 72-01472 A03 from the Atmospheric\nSciences Section of the National Science Foundation,\nand under Grant NGL 22-007-228 from the\nNational Aeronautics and Space Administration.\nOne of us (Y.Y.) also acknowledges support by\nKitt Peak National Observatory under NASA\nContract NAS 7-100.", "abstract": "We give a quantitative theory of line formation in an atmosphere above a surface with backscattering properties. Sufficiently high spatial and spectral resolution spectra of resonance lines in Io region A can yield data on the surface scattering properties as well as the number density of scattering molecules. We discuss macroscopically homogenous models of scattering from the surface of Io and conclude that multiple reflection from crystal facets is the most likely cause for the observed geometric albedo and phase variation.", "date": "1976-09", "date_type": "published", "publication": "Icarus", "volume": "29", "number": "1", "publisher": "Elsevier", "pagerange": "57-67", "id_number": "CaltechAUTHORS:20140811-135656465", "issn": "0019-1035", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140811-135656465", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "DES 72-01472 A03" }, { "agency": "NASA", "grant_number": "NGL 22-007-228" }, { "agency": "NASA", "grant_number": "NAS 7-100" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/0019-1035(76)90102-0", "resource_type": "article", "pub_year": "1976", "author_list": "Yung, Yuk L. and Goody, Richard M." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/6e7qd-s8824", "eprint_id": 48946, "eprint_status": "archive", "datestamp": "2023-08-22 01:08:57", "lastmod": "2023-10-17 20:33:57", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "McElroy-M-B", "name": { "family": "McElroy", "given": "Michael B." } }, { "id": "Elkins-J-W", "name": { "family": "Elkins", "given": "James W." } }, { "id": "Wofsy-S-C", "name": { "family": "Wofsy", "given": "Steven C." }, "orcid": "0000-0002-3990-6737" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk Ling" }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Sources and sinks for atmospheric N_2O", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1976 by the American Geophysical Union.\n\nReceived December 8, 1975; accepted December 11, 1975.\n\nIt is a pleasure to acknowledge instructive conversations with W. S. Broecker. This research was supported in part by\nthe Atmospheric Research Section, National Science Foundation, and\nin part by NASA grant NSG 2031 to Harvard University.\n\nPublished - rog493.pdf
", "abstract": "Observations of the temporal and spatial distribution of N_2O in solution are not yet sufficient to permit quantitative assessment of the role of the ocean in the budget of atmospheric N_2O. Consideration of the global nitrogen cycle suggests that the land should be the primary source of N_2O. The gas is removed in the atmosphere by photolysis and by reaction with O(\u00b9D), and there may be additional sinks in the ocean.", "date": "1976-05", "date_type": "published", "publication": "Reviews of Geophysics", "volume": "14", "number": "2", "publisher": "American Geophysical Union", "pagerange": "143-150", "id_number": "CaltechAUTHORS:20140826-150426644", "issn": "8755-1209", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140826-150426644", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF" }, { "agency": "NASA", "grant_number": "NSG 2031" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/RG014i002p00143", "primary_object": { "basename": "rog493.pdf", "url": "https://authors.library.caltech.edu/records/6e7qd-s8824/files/rog493.pdf" }, "resource_type": "article", "pub_year": "1976", "author_list": "McElroy, Michael B.; Elkins, James W.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/egmhr-rcb57", "eprint_id": 52887, "eprint_status": "archive", "datestamp": "2023-08-22 01:07:21", "lastmod": "2023-10-18 21:44:32", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "McElroy-M-B", "name": { "family": "McElroy", "given": "M. B." } }, { "id": "Wofsy-S-C", "name": { "family": "Wofsy", "given": "S. C." }, "orcid": "0000-0002-3990-6737" }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Y. L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Agricultural Perturbations of the Nitrogen Cycle and Related Impact on Atmospheric N_2O and Ozone", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1976 American Geophysical Union.\n\nPublished - Yung_1976p600.pdf
", "abstract": "The available data are employed to\nidentify the fate of agricultural nitrogen\nin the environment. Best estimates\npredict denitrification of nearly 50% of\nfertilizer nitrogen in less than 10 years\nafter application. We also discuss in\ndetail the expected demand curve for agricultural N. If population growth\ncontinues at projected levels, between 100\nand 200 M tons/yr of agricultural N will\nbe needed by the year 2000. We estimate\nthat as a result, atmospheric N_2O could be\nmore than doubled by 2050, and that\nperturbations of O_3 at that time could\nrange from 10 to more than 20%. Major\nuncertainties remain however, and we\nemphasize the importance of further\nexperimental research into the nitrogen\ncycle.", "date": "1976-04", "date_type": "published", "publication": "Transactions - American Geophysical Union", "volume": "57", "number": "8", "publisher": "American Geophysical Union", "pagerange": "600", "id_number": "CaltechAUTHORS:20141216-135114126", "issn": "0002-8606", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20141216-135114126", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "primary_object": { "basename": "Yung_1976p600.pdf", "url": "https://authors.library.caltech.edu/records/egmhr-rcb57/files/Yung_1976p600.pdf" }, "resource_type": "article", "pub_year": "1976", "author_list": "McElroy, M. B.; Wofsy, S. C.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/bke6m-g4d16", "eprint_id": 48349, "eprint_status": "archive", "datestamp": "2023-08-22 01:07:11", "lastmod": "2023-10-17 18:44:07", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk Ling" }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Elastic collision in one dimension viewed as a linear transformation", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1976 American Association of Physics Teachers. \n\nReceived 15 July 1975.\n\nPublished - 1.10446.pdf
", "abstract": "The solution for a two-body elastic collision in one dimension is well known. Let u_1, u_2 be the initial velocities and \u03bd_1, \u03bd_2 be the velocities after collision, where the indices 1 and 2 refer to the particle with mass m_1 and m_2, respectively. The final velocities can be solved in terms of the initial velocities.", "date": "1976-04", "date_type": "published", "publication": "American Journal of Physics", "volume": "44", "number": "4", "publisher": "American Association of Physics Teachers", "pagerange": "389-390", "id_number": "CaltechAUTHORS:20140811-152044018", "issn": "0002-9505", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140811-152044018", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1119/1.10446", "primary_object": { "basename": "1.10446.pdf", "url": "https://authors.library.caltech.edu/records/bke6m-g4d16/files/1.10446.pdf" }, "resource_type": "article", "pub_year": "1976", "author_list": "Yung, Yuk Ling" }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/zg7bv-37j15", "eprint_id": 48805, "eprint_status": "archive", "datestamp": "2023-08-22 01:07:15", "lastmod": "2023-10-17 20:26:47", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Y. L." }, "orcid": "0000-0002-4263-2562" }, { "id": "McElroy-M-B", "name": { "family": "McElroy", "given": "M. B." } }, { "id": "Wofsy-S-C", "name": { "family": "Wofsy", "given": "S. C." }, "orcid": "0000-0002-3990-6737" } ] }, "title": "Reply to \"Comment by A. Appleby, D. Lilian and H. B. Singh on 'Atmospheric halocarbons: A discussion with emphasis on chloroform'\"", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1976 by the American Geophysical Union.\n\nReceived February 9, 1976; accepted February 9, 1976.\n\nPublished - grl326.pdf
", "abstract": "No abstract.", "date": "1976-04", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "3", "number": "4", "publisher": "American Geophysical Union", "pagerange": "238-238", "id_number": "CaltechAUTHORS:20140822-101049551", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140822-101049551", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/GL003i004p00238", "primary_object": { "basename": "grl326.pdf", "url": "https://authors.library.caltech.edu/records/zg7bv-37j15/files/grl326.pdf" }, "resource_type": "article", "pub_year": "1976", "author_list": "Yung, Y. L.; McElroy, M. B.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/yy11m-mxb16", "eprint_id": 48809, "eprint_status": "archive", "datestamp": "2023-08-22 01:01:20", "lastmod": "2023-10-17 20:26:58", "type": "book_section", "metadata_visibility": "show", "creators": { "items": [ { "id": "Brown-R-A", "name": { "family": "Brown", "given": "R. A." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Y. L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Io, its Atmosphere and Optical Emissions", "ispublished": "unpub", "full_text_status": "public", "note": "\u00a9 1976 University of Arizona Press.\n\nWe are pleased to acknowledge many helpful discussions\nwith our colleagues R. Goody, M. McElroy, F. Murcray. and W.\nSmyth. We thank R. Carlson. A. Eviatar. D. Hunten, D. Judge, D. Matson.\nM. Rosen, L. Trafton, and P. Wehinger for critical comments on the manuscript.\nThis research was funded by the Atmospheric Sciences Section of\nthe National Science Foundation under grant DES72-01472 A03 to Harvard\nUniversity. One of us (Yuk L. Yung) acknowledges support by Kitt\nPeak National Observatory under NASA Contract NAS7-100.\n\nPublished - Yung_1976p1102.pdf
", "abstract": "Io is surrounded by a halo of atoms which radiate in emission lines. This was discovered by groundbased observations in 1973, a year before Pioneer 10 passed through the Jovian system. Earlier optical and radio observers had reported other anomalies associated with Io, and the Pioneer spacecraft discovered an ultraviolet emission cloud around the satellite and a substantial ionosphere. A new field of planetary research is dedicated to integrating these phenomena into a model of Io and of the Jovian environment with which it strongly interacts.\n\nSodium dominates the optical emission cloud around Io. The production rate is very large and has not yet been satisfactorily explained. Sputtering by charged particle bombardment may play an important role. The primary excitation mechanism is the resonant scattering of sunlight. While the sodium cloud is brightest near Io, it extends around the entire orbit and is present at low levels in the general Jovian environment. The ionospheric electron density on Io is comparable to that on Mars, a surprising result since the solar flus is much weaker. Here, again, Io's charged particle environment may play an important part. The observed electron profiles plus the constraints provided by the emission cloud are consistent with at least two models of Io's neutral atmosphere.", "date": "1976", "date_type": "published", "publisher": "University of Arizona Press", "place_of_pub": "Tucson, AZ", "pagerange": "1102-1145", "id_number": "CaltechAUTHORS:20140822-103719910", "isbn": "9780816505302", "book_title": "Jupiter: studies of the interior, atmosphere, magnetosphere, and satellites", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140822-103719910", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "DES72-01472 A03" }, { "agency": "NASA", "grant_number": "NAS7-100" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "contributors": { "items": [ { "id": "Gehrels-T", "name": { "family": "Gehrels", "given": "Tom" } }, { "id": "Matthews-M-S", "name": { "family": "Matthews", "given": "Mildred Shapley" } } ] }, "primary_object": { "basename": "Yung_1976p1102.pdf", "url": "https://authors.library.caltech.edu/records/yy11m-mxb16/files/Yung_1976p1102.pdf" }, "resource_type": "book_section", "pub_year": "1976", "author_list": "Brown, R. A. and Yung, Y. L." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/k1bae-36788", "eprint_id": 48804, "eprint_status": "archive", "datestamp": "2023-08-22 00:54:18", "lastmod": "2023-10-17 20:26:45", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk Ling" }, "orcid": "0000-0002-4263-2562" }, { "id": "McElroy-M-B", "name": { "family": "McElroy", "given": "Michael B." } }, { "id": "Wofsy-S-C", "name": { "family": "Wofsy", "given": "Steven C." }, "orcid": "0000-0002-3990-6737" } ] }, "title": "Atmospheric halocarbons: A discussion with emphasis on chloroform", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1975 American Geophysical Union.\n\nReceived June 12, 1975; Accepted August 7, 1975.\n\nWe are indebted particularly to J.C. Morris who shared readily with us\nhis remarkable insights in to the chemistry of chlorinated water. We thank\nC.L. Klingman for providing us with the contents of Table 3, and R.\nRasmussen for making available his unpublished measurements. The work\nwas supported in part by the Atmospheric Sciences Division of the\nNational Science Foundation under Grant GA33990X and by the National\nAeronautics and Space Administration under Grant NASA NSG 2031 to\nHarvard University.\n\nPublished - grl208.pdf
", "abstract": "Bleaching of paper pulp represents a major industrial use of chlorine and could provide an environmentally significant source of atmospheric halocarbons. The related global production of chloroform is estimated at 3 \u00d7 10^5 ton yr^(\u22121) and there could be additional production associated with atmospheric decomposition of perchloroethylene. Estimates are given for the production of methyl chloride, methyl bromide and methyl iodide, 5.2 \u00d7 10^6, 7.7 \u00d7 10^4, and 7.4 \u00d7 10^5 ton yr^(\u22121) respectively. The relative yields of CH_3Cl, CH_3Br and CH_3I are consistent with the hypothesis of a marine biological source for these compounds. Concentrations of other halocarbons observed in the atmosphere appear to indicate industrial sources.", "date": "1975-09", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "2", "number": "9", "publisher": "American Geophysical Union", "pagerange": "397-399", "id_number": "CaltechAUTHORS:20140822-100358485", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140822-100358485", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "GA33990X" }, { "agency": "NASA", "grant_number": "NSG 2031" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/GL002i009p00397", "primary_object": { "basename": "grl208.pdf", "url": "https://authors.library.caltech.edu/records/k1bae-36788/files/grl208.pdf" }, "resource_type": "article", "pub_year": "1975", "author_list": "Yung, Yuk Ling; McElroy, Michael B.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/a2rf3-95h23", "eprint_id": 49927, "eprint_status": "archive", "datestamp": "2023-08-22 00:50:12", "lastmod": "2023-10-17 22:19:23", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Wofsy-S-C", "name": { "family": "Wofsy", "given": "Steven C." }, "orcid": "0000-0002-3990-6737" }, { "id": "McElroy-M-B", "name": { "family": "McElroy", "given": "Michael B." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk Ling" }, "orcid": "0000-0002-4263-2562" } ] }, "title": "The chemistry of atmospheric bromine", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1975 American Geophysical Union.\n\nReceived April 22, 1975; accepted May 16, 1975.\n\nWe are indebted to C. Kolb, I. Chet and R. Mitchell for\nvaluable discussions and, to S. Coroniti and J. Plonka for\nuseful communications. This work was supported by the\nNational Aeronautics and Space Administration under Grant\nNASA NSG 2031 and by the Atmospheric Sciences Division\nof the National Science Foundation under Grant GA33990X to Harvard University.\n\nPublished - grl162.pdf
", "abstract": "Bromine may act as a catalyst for recombination of ozone and could be more efficient than either nitric oxide or chlorine. The lower atmosphere contains small concentrations of gaseous bromine produced in part by marine activity, in part by volatilization of particulate material released during the combustion of leaded gasoline, with an additional contribution due to the use of methyl bromide as an agricultural fumigant. Observations by Lazrus et. al. (1975) indicate small concentrations of bromine, \u223c 10^(\u221211) (v/v) in the contemporary stratosphere and appear to imply a reduction of approximately 0.3% in the global budget of O_3. Estimates are given for future reductions in O_3 which might occur if the use of CH_3Br as an agricultural fumigant were to continue to grow at present rates.", "date": "1975-06", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "2", "number": "6", "publisher": "American Geophysical Union", "pagerange": "215-218", "id_number": "CaltechAUTHORS:20140923-100059401", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140923-100059401", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NSG 2031" }, { "agency": "NSF", "grant_number": "GA33990X" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/GL002i006p00215", "primary_object": { "basename": "grl162.pdf", "url": "https://authors.library.caltech.edu/records/a2rf3-95h23/files/grl162.pdf" }, "resource_type": "article", "pub_year": "1975", "author_list": "Wofsy, Steven C.; McElroy, Michael B.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/nrn5y-2pk03", "eprint_id": 49975, "eprint_status": "archive", "datestamp": "2023-08-22 00:45:18", "lastmod": "2023-10-17 22:24:57", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "McElroy-M-B", "name": { "family": "McElroy", "given": "Michael B." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk Ling" }, "orcid": "0000-0002-4263-2562" } ] }, "title": "The atmosphere and ionosphere of Io", "ispublished": "pub", "full_text_status": "public", "keywords": "atmospheres, planetary, Jupiter, satellites", "note": "\u00a9 1975 The American Astronomical Society. Provided by the NASA Astrophysics Data System.\n\nReceived 1974 May 30; revised 1974 August 23.\n\nWe are indebted to R. W. Carlson, D. L. Judge, A. Kliore, S. I. Rasool, J. A. Simpson, and J. H. Wolfe for informative discussions of the Pioneer JO data. We acknowledge also the patience and stimulation of various\ncolleagues, particularly R. A. Brown, H. Ehrenreich, R. M. Goody, and S. C. Wofsy, who bore with us during the\ncourse of this research. The work was supported by the Atmospheric Sciences Section of the National Science\nFoundation under grant GA-33990X to Harvard University. We also acknowledge partial support from the National Aeronautics and Space Administration contract NGL 22-007-228 to Harvard University.\n\nPublished - 1975ApJ___196__227M.pdf
", "abstract": "A variety of models for Io's atmosphere, ionosphere, surface, and environment are developed and discussed\nin the context of recent observational data. The sodium emission detected by Brown appears to require a collisional\nexcitation process in Io's atmosphere, and the extended sodium emission measured by Trafton et al. may require scattering of the planetary radiation by an extended sodium cloud. The sodium is presumably present initially in bound form on Io's surface and may be released by the sputtering mechanism suggested by Matson et al. The ionosphere detected by the radio occultation experiment on Pioneer 10 could be attributed to photoionization of atmospheric sodium if Io's atmosphere could sustain significant vertical motions, of order 1 s^(-1) directed up during the day, down at night. Vertical motions of this magnitude could be driven by condensation of atmospheric NH_3. The total density of gas at Io's surface appears to lie in the range 10^(10)-10^(12) molecules cm^(-3). Corpuscular ionization could play an additional role for the Ionosphere. In this case the satellite should exhibit an exceedingly bright, ~ 10 kR, airglow at L\u0251. The incomplete hydrogen torus observed by Judge and Carlson in the vicinity of Io requires a large supply of hydrogen from the satellite's atmosphere. The escape flux should be of order 10^(11) cm^(-2) s^(-1) and could be maintained by photolysis of atmospheric NH_3. The observed geometry of the hydrogen torus appears to require a surprisingly short lifetime, ~ 10^5 s, for neutral hydrogen near Io's orbit, and may indicate the presence of a large flux, ~ 10^9 cm ^(-2) s^(-1), of low-energy protons in Jupiter's magnetosphere. Implications of the hydrogen torus for the energy and mass balance of Jupiter's magnetosphere\nare discussed briefly, and observational programs are identified which might illuminate present uncertainties in\nour understanding of Io.", "date": "1975-02-15", "date_type": "published", "publication": "Astrophysical Journal", "volume": "196", "number": "1", "publisher": "American Astronomical Society", "pagerange": "227-250", "id_number": "CaltechAUTHORS:20140924-085334547", "issn": "0004-637X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140924-085334547", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "GA-33990X" }, { "agency": "NASA", "grant_number": "NGL 22-007-228" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1086/153408", "primary_object": { "basename": "1975ApJ___196__227M.pdf", "url": "https://authors.library.caltech.edu/records/nrn5y-2pk03/files/1975ApJ___196__227M.pdf" }, "resource_type": "article", "pub_year": "1975", "author_list": "McElroy, Michael B. and Yung, Yuk Ling" }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/2ccxx-d2h71", "eprint_id": 47404, "eprint_status": "archive", "datestamp": "2023-08-22 00:42:12", "lastmod": "2024-01-13 16:06:55", "type": "book_section", "metadata_visibility": "show", "creators": { "items": [ { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk L." }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Io: Recent observations", "ispublished": "unpub", "full_text_status": "restricted", "note": "\u00a9 1975 D. Reidel Publishing Company.\n\nI would like to thank M. B. McElroy for many helpful suggestions and critical reading\nof the manuscript. I am indebted to J. T. Bergstrahl, R. W. Carlson. D. P. Cruikshank.\nT. V. Johnson, and D. L. Matson for discussion of their recent work. This work was\nsupported by the Atmospheric Sciences section of the National Science Foundation\nunder grant no. GA-33990X to Harvard University.", "abstract": "Our knowledge of Io has progressed dramatically in the past year. Prior to 1973,\nobservations of Io made at optical, IR and radio wavelengths have revealed that this\ninnermost Galilean satellite of Jupiter is unusual in a number of ways. A list would\ninclude post-eclipse brightening, high near-IR albedo, puzzling features (or lack of\nfeatures) in the reflection spectrum, discordant brightness temperatures measured at\n10 and 20 \u03bcm, and modulation of Jovian decametric activity. We now understand\nthat Io has an atmosphere and an ionosphere. Their presence and interaction with the\nJovian magnetosphere may account for much of the unusual behavior of the enigmatic\nsatellite.\nThe emphasis of this review will be on recent observations and a few specific\nproblems associated with their interpretations. For a more general review the reader\nis referred to Parkinson (1975).", "date": "1975", "date_type": "published", "publisher": "D. Reidel Publishing", "place_of_pub": "Dordrecht, Netherlands", "pagerange": "441-446", "id_number": "CaltechAUTHORS:20140722-160805622", "isbn": "9789027705754", "book_title": "Atmospheres of Earth and the Planets", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140722-160805622", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "GA-33990X" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "contributors": { "items": [ { "id": "McCormac-B-M", "name": { "family": "McCormac", "given": "Billy M." } } ] }, "doi": "10.1007/978-94-010-1799-2_34", "resource_type": "book_section", "pub_year": "1975", "author_list": "Yung, Yuk L." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/shn27-2pv04", "eprint_id": 49905, "eprint_status": "archive", "datestamp": "2023-08-22 00:30:38", "lastmod": "2023-10-17 22:18:23", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "McElroy-M-B", "name": { "family": "McElroy", "given": "Michael B." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk Ling" }, "orcid": "0000-0002-4263-2562" }, { "id": "Brown-R-A", "name": { "family": "Brown", "given": "Robert A." } } ] }, "title": "Sodium Emission from Io: Implications", "ispublished": "pub", "full_text_status": "public", "keywords": "abundances - Jupiter - satellites", "note": "\u00a9 1974 The American Astronomical Society.\n\nReceived 1973 November 29.\n\nThis research was funded by the Atmospheric\nSciences Section of the National Science Foundation\nunder grant GA-33990X to Harvard University.\n\nPublished - 1974ApJ___187L_127M.pdf
", "abstract": "The surface of lo may be covered with a layer of ammonia ice containing trace amounts of sodium\npotassium, and calcium; and atmospheric nitrogen could be formed as a photochemical product of\nammonia photolysis. Intense sporadic sodium emission from Io can be excited by collisions involving vibrationally excited nitrogen molecules. These metastable molecules may be formed by electron impact,\nwith electrons energized by an auroral mechanism. In order to account for the intensity ratio of the\nsodium doublet, it is necessary to invoke scattering in a thick gaseous envelope ejected by Io.", "date": "1974-02", "date_type": "published", "publication": "Astrophysical Journal Letters", "volume": "187", "number": "3", "publisher": "American Astronomical Society", "pagerange": "L127-L130", "id_number": "CaltechAUTHORS:20140922-132821232", "issn": "2041-8205", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140922-132821232", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "GA-33990X" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1086/181414", "primary_object": { "basename": "1974ApJ___187L_127M.pdf", "url": "https://authors.library.caltech.edu/records/shn27-2pv04/files/1974ApJ___187L_127M.pdf" }, "resource_type": "article", "pub_year": "1974", "author_list": "McElroy, Michael B.; Yung, Yuk Ling; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/cwpdm-qzm86", "eprint_id": 49973, "eprint_status": "archive", "datestamp": "2023-08-23 23:47:48", "lastmod": "2023-10-17 22:24:53", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "McElroy-M-B", "name": { "family": "McElroy", "given": "Michael B." } }, { "id": "Sze-N-D", "name": { "family": "Sze", "given": "Nien Dak" } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Yuk Ling" }, "orcid": "0000-0002-4263-2562" } ] }, "title": "Photochemistry of the Venus Atmosphere", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1973 American Meteorological Society. Manuscript received 14 May 1973, in revised form 27 June 1973. \n\nThis work was supported by the Atmospheric Sciences Division of the National Science Foundation under Grant GA33990X to Harvard University. We thank the Harvard High Energy Group\nfor permission to use their computer (on a low priority\nbasis, of course) for the low energy research described here. The computer is supported by AEC Contract AT (11-1)-3064. We are indebted to Mark Rosen for helpful comments.\n\nPublished - 1520-0469_1973_030_1437_potva_2.0.co;2.pdf
Published - 1520-0469_1973_030_1437_potva_2.0.co=003b2.pdf
", "abstract": "Carbon monoxide, produced in the Venus atmosphere by photolysis of CO_2, is removed mainly by reaction with OH. The radical OH is formed in part by photolysis of H_2O_2, in part by reaction of O with HO_2. Photolysis of HCl provides a major source of H radicals near the visible clouds of Venus and plays a major role in the overall photochemistry. The mixing ratio of O_2 is estimated to be approximately 10^(\u22127), about a factor of 10 less than a recent observational upper limit reported by Traub and Carleton. A detailed model, which accounts for the photochemical stability of Venus CO_2, is presented and discussed.", "date": "1973-10", "date_type": "published", "publication": "Journal of the Atmospheric Sciences", "volume": "30", "number": "7", "publisher": "American Meteorological Society", "pagerange": "1437-1447", "id_number": "CaltechAUTHORS:20140924-084022391", "issn": "0022-4928", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140924-084022391", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "AEC Contract", "grant_number": "AT (11-1)-3064" }, { "agency": "NSF", "grant_number": "GA33990X" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1175/1520-0469(1973)030<1437:POTVA>2.0.CO;2", "primary_object": { "basename": "1520-0469_1973_030_1437_potva_2.0.co=003b2.pdf", "url": "https://authors.library.caltech.edu/records/cwpdm-qzm86/files/1520-0469_1973_030_1437_potva_2.0.co=003b2.pdf" }, "resource_type": "article", "pub_year": "1973", "author_list": "McElroy, Michael B.; Sze, Nien Dak; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/8qywk-kjx05", "eprint_id": 49730, "eprint_status": "archive", "datestamp": "2023-08-23 23:47:44", "lastmod": "2023-10-17 22:07:45", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Lundeen-S-R", "name": { "family": "Lundeen", "given": "S. R." } }, { "id": "Yung-Y-L", "name": { "family": "Yung", "given": "Y. L." }, "orcid": "0000-0002-4263-2562" }, { "id": "Pipkin-F-M", "name": { "family": "Pipkin", "given": "F. M." } } ] }, "title": "Separated oscillatory field measurements on fast hydrogen", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 1973 North-Holland Publishing Co.\n\nWork supported by NSF GP-22787.", "abstract": "An analysis of the line shape obtained in separated oscillatory field measurements of the hydrogen n = 3 Lamb shift is presented. The non-ideal interaction geometry is shown to be capable of producing line distortions on the order of 1% of peak quenching in such experiments on unstable levels. Other lineshape details of interest for precision work are explored.", "date": "1973-07", "date_type": "published", "publication": "Nuclear Instruments and Methods", "volume": "110", "publisher": "Elsevier", "pagerange": "355-360", "id_number": "CaltechAUTHORS:20140915-153810912", "issn": "0029-554X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140915-153810912", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "GP-22787" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/0029-554X(73)90712-X", "resource_type": "article", "pub_year": "1973", "author_list": "Lundeen, S. R.; Yung, Y. L.; et el." } ]