[ { "id": "https://authors.library.caltech.edu/records/hnnwr-z0490", "eprint_status": "archive", "datestamp": "2023-12-13 18:43:11", "lastmod": "2023-12-13 18:43:12", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Schulze-Benjamin-C", "name": { "family": "Schulze", "given": "Benjamin C." }, "orcid": "0000-0002-6405-8872" }, { "id": "Ward-Ryan-X", "name": { "family": "Ward", "given": "Ryan X." }, "orcid": "0000-0003-2317-3310" }, { "id": "Pfannerstill-Eva-Y", "name": { "family": "Pfannerstill", "given": "Eva Y." }, "orcid": "0000-0001-7715-1200" }, { "id": "Zhu-Qindan", "name": { "family": "Zhu", "given": "Qindan" }, "orcid": "0000-0003-2173-4014" }, { "id": "Arata-Caleb", "name": { "family": "Arata", "given": "Caleb" }, "orcid": "0000-0002-0170-8794" }, { "id": "Place-Bryan-K", "name": { "family": "Place", "given": "Bryan" }, "orcid": "0000-0002-9224-2837" }, { "id": "Nussbaumer-Clara", "name": { "family": "Nussbaumer", "given": "Clara" }, "orcid": "0000-0002-5662-8476" }, { "id": "Wooldridge-Paul", "name": { "family": "Wooldridge", "given": "Paul" }, "orcid": "0000-0003-2711-5900" }, { "id": "Woods-Roy", "name": { "family": "Woods", "given": "Roy" }, "orcid": "0000-0002-3632-6374" }, { "id": "Bucholtz-Anthony", "name": { "family": "Bucholtz", "given": "Anthony" } }, { "id": "Cohen-Ronald-C", "name": { "family": "Cohen", "given": "Ronald C." }, "orcid": "0000-0001-6617-7691" }, { "id": "Goldstein-Allen-H", "name": { "family": "Goldstein", "given": "Allen H." }, "orcid": "0000-0003-4014-4896" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Seinfeld-J-H", "name": { "family": "Seinfeld", "given": "John H." }, "orcid": "0000-0003-1344-4068" } ] }, "title": "Methane Emissions from Dairy Operations in California's San Joaquin Valley Evaluated Using Airborne Flux Measurements", "ispublished": "pub", "full_text_status": "public", "keywords": "Environmental Chemistry; General Chemistry", "note": "
\u00a9 2023 American Chemical Society.
\n\nWe would like to thank Greg Cooper, Bryce Kujat, and George Loudakis for their dedicated mission support during RECAP-CA. We would also like to thank Timothy Lueker, Jooil Kim, and Ralph Keeling for assistance with the Picarro G2401-m calibrations at the Scripps Institution of Oceanography. This research was funded by the following sources: California Air Resources Board Contract numbers 20RD003 and 20AQP012, NOAA Climate Program Office's Atmospheric Chemistry, Carbon Cycle, and Climate program, grant number NA22OAR4310540 [UCB]/NA22OAR4310541 [AD], Office of Naval Research Defense University Research Instrumentation Program grant number N00014-19-1-2108. We thank the Resnick Sustainability Institute at Caltech for funding the purchase of the Picarro G2401-m.
\n\nThe authors declare no competing financial interest.
", "abstract": "State inventories indicate that dairy operations account for nearly half of California's methane budget. Recent analyses suggest, however, that these emissions may be underestimated, complicating efforts to develop emission reduction strategies. Here, we report estimates of dairy methane emissions in the southern San Joaquin Valley (SJV) of California in June 2021 using airborne flux measurements. We find average dairy methane fluxes of 512 \u00b1 178 mg m\u207b\u00b2 h\u207b\u00b9 from a region of 300+ dairies near Visalia, CA using a combination of eddy covariance and mass balance-based techniques, corresponding to 118 \u00b1 41 kg dairy\u207b\u00b9 h\u207b\u00b9. These values estimated during our June campaign are 39 \u00b1 48% larger than annual average estimates from the recently developed VISTA-CA inventory. We observed notable increases in emissions with temperature. Our estimates align well with inventory predictions when parametrizations for the temperature dependence of emissions are applied. Our measurements further demonstrate that the VISTA-CA emission inventory is considerably more accurate than the EPA GHG-I inventory in this region. Source apportionment analyses confirm that dairy operations produce the majority of methane emissions in the southern SJV (\u223c65%). Fugitive oil and gas (O&G) sources account for the remaining \u223c35%. Our results support the accuracy of the process-based models used to develop dairy emission inventories and highlight the need for additional investigation of the meteorological dependence of these emissions.
", "date": "2023-12-05", "date_type": "published", "publication": "Environmental Science & Technology", "volume": "57", "number": "48", "publisher": "American Chemical Society", "pagerange": "19519-19531", "issn": "0013-936X", "official_url": "https://authors.library.caltech.edu/records/hnnwr-z0490", "funders": { "items": [ { "grant_number": "20RD003" }, { "grant_number": "20AQP012" }, { "grant_number": "NA22OAR4310540" }, { "grant_number": "NA22OAR4310541" }, { "grant_number": "N00014-19-1-2108" }, { "grant_number": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/acs.est.3c03940", "primary_object": { "basename": "es3c03940_si_001.pdf", "url": "https://authors.library.caltech.edu/records/hnnwr-z0490/files/es3c03940_si_001.pdf" }, "resource_type": "article", "pub_year": "2023", "author_list": "Schulze, Benjamin C.; Ward, Ryan X.; et el." }, { "id": "https://authors.library.caltech.edu/records/t31be-g4j36", "eprint_status": "archive", "datestamp": "2023-12-13 19:17:31", "lastmod": "2023-12-13 19:17:31", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "Let's Abandon the \"High NO\u2093\" and \"Low NO\u2093\" Terminology", "ispublished": "pub", "full_text_status": "public", "note": "
\u00a9 2023 American Chemical Society. Made available for a limited time for personal research and study only License.
\n\nThis essay was originally published in issue 50 of IGAC News (July, 2013). A decade later, I feel it is still relevant. I advocate that as authors, reviewers, and editors we work to weed out the high and low NOx terminology from our manuscripts. Reprinted with permission of IGAC News. Views expressed in this viewpoint are those of the author and not necessarily the views of the ACS.
\n\nThe author declares no competing financial interest.
", "abstract": "\"High-NO\u2093\" and \"low-NO\u2093\" are used ubiquitously in the atmospheric chemistry community as shorthand terms meant to describe the chemical end-member photochemical conditions that span from \"urban\"/\"anthropogenically-impacted\" to \"remote\"/\"pristine\". They do not, however, have precise or accepted definitions. Following a rather heated discussion at the 2012 Atmospheric Chemistry Mechanism conference in Davis, California, I was tasked with suggesting appropriate definitions. I've come to the opinion that these terms cause more confusion than they do insight and we should abandon them entirely.
", "date": "2023-11-29", "date_type": "published", "publication": "ACS ES&T Air", "publisher": "American Chemical Society", "issn": "2837-1402", "official_url": "https://authors.library.caltech.edu/records/t31be-g4j36", "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1021/acsestair.3c00055", "primary_object": { "basename": "wennberg-2023-let-s-abandon-the-high-nox-and-low-nox-terminology.pdf", "url": "https://authors.library.caltech.edu/records/t31be-g4j36/files/wennberg-2023-let-s-abandon-the-high-nox-and-low-nox-terminology.pdf" }, "resource_type": "article", "pub_year": "2023", "author_list": "Wennberg, Paul O." }, { "id": "https://authors.library.caltech.edu/records/4b2k5-xt326", "eprint_status": "archive", "datestamp": "2023-12-13 19:24:34", "lastmod": "2023-12-13 19:24:34", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Yu-Hongmin", "name": { "family": "Yu", "given": "Hongmin" }, "orcid": "0000-0001-5099-3950" }, { "id": "M\u00f8ller-Kristian-H", "name": { "family": "M\u00f8ller", "given": "Kristian H." }, "orcid": "0000-0001-8070-8516" }, { "id": "Buenconsejo-Reina-S", "name": { "family": "Buenconsejo", "given": "Reina S." }, "orcid": "0000-0002-0162-905X" }, { "id": "Crounse-John-D", "name": { "family": "Crounse", "given": "John D." }, "orcid": "0000-0001-5443-729X" }, { "id": "Kjaergaard-Henrik-G", "name": { "family": "Kjaergaard", "given": "Henrik G." }, "orcid": "0000-0002-7275-8297" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "Atmospheric Photo-Oxidation of 2-Ethoxyethanol: Autoxidation Chemistry of Glycol Ethers", "ispublished": "pub", "full_text_status": "public", "keywords": "Physical and Theoretical Chemistry", "note": "\u00a9 2023 American Chemical Society.
\n\nThis material is based upon work supported by grants from the Alfred P. Sloan Foundation (G-2019-12281) and from the U.S. National Science Foundation (CHE-2305204). This work is also supported by the Novo Nordisk Foundation Grant NNF19OC0057374. We thank Sara E. Murphy for advice on experimental design and assistance with experiments and instruments. We thank James Park for providing support on the analysis of GC data. We also thank the support from the High Performance Computing Center at the University of Copenhagen.
\n\nThe authors declare no competing financial interest.
", "abstract": "We investigate the gas-phase photo-oxidation of 2-ethoxyethanol (2-EE) initiated by the OH radical with a focus on its autoxidation pathways. Gas-phase autoxidation\u2500intramolecular H-shifts followed by O\u2082 addition\u2500has recently been recognized as a major atmospheric chemical pathway that leads to the formation of highly oxygenated organic molecules (HOMs), which are important precursors for secondary organic aerosols (SOAs). Here, we examine the gas-phase oxidation pathways of 2-EE, a model compound for glycol ethers, an important class of volatile organic compounds (VOCs) used in volatile chemical products (VCPs). Both experimental and computational techniques are applied to analyze the photochemistry of the compound. We identify oxidation products from both bimolecular and autoxidation reactions from chamber experiments at varied HO\u2082 levels and provide estimations of rate coefficients and product branching ratios for key reaction pathways. The H-shift processes of 2-EE peroxy radicals (RO\u2082) are found to be sufficiently fast to compete with bimolecular reactions under modest NO/HO\u2082 conditions. More than 30% of the produced RO\u2082 are expected to undergo at least one H-shift for conditions typical of modern summer urban atmosphere, where RO\u2082 bimolecular lifetime is becoming >10 s, which implies the potential for glycol ether oxidation to produce considerable amounts of HOMs at reduced NO\u2093 levels and elevated temperature. Understanding the gas-phase autoxidation of glycol ethers can help fill the knowledge gap in the formation of SOA derived from oxygenated VOCs emitted from VCP sources.
", "date": "2023-11-16", "date_type": "published", "publication": "Journal of Physical Chemistry A", "volume": "127", "number": "45", "publisher": "American Chemical Society", "pagerange": "9564-9579", "issn": "1089-5639", "official_url": "https://authors.library.caltech.edu/records/4b2k5-xt326", "funders": { "items": [ { "grant_number": "G-2019-12281" }, { "grant_number": "CHE-2305204" }, { "grant_number": "NNF19OC0057374" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1021/acs.jpca.3c04456", "primary_object": { "basename": "jp3c04456_si_001.pdf", "url": "https://authors.library.caltech.edu/records/4b2k5-xt326/files/jp3c04456_si_001.pdf" }, "resource_type": "article", "pub_year": "2023", "author_list": "Yu, Hongmin; M\u00f8ller, Kristian H.; et el." }, { "id": "https://authors.library.caltech.edu/records/vzqd9-96j05", "eprint_id": 121932, "eprint_status": "archive", "datestamp": "2023-08-22 20:56:40", "lastmod": "2023-10-20 16:48:39", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Guan-Yifan", "name": { "family": "Guan", "given": "Yifan" } }, { "id": "Keppel-Aleks-Gretchen", "name": { "family": "Keppel-Aleks", "given": "Gretchen" }, "orcid": "0000-0003-2213-0044" }, { "id": "Doney-Scott-C", "name": { "family": "Doney", "given": "Scott C." }, "orcid": "0000-0002-3683-2437" }, { "id": "Petri-Christof", "name": { "family": "Petri", "given": "Christof" }, "orcid": "0000-0002-7010-5532" }, { "id": "Pollard-Dave", "name": { "family": "Pollard", "given": "Dave" }, "orcid": "0000-0001-9923-2984" }, { "id": "Wunch-D", "name": { "family": "Wunch", "given": "Debra" }, "orcid": "0000-0002-4924-0377" }, { "id": "Hase-Frank", "name": { "family": "Hase", "given": "Frank" } }, { "id": "Ohyama-Hirofumi", "name": { "family": "Ohyama", "given": "Hirofumi" }, "orcid": "0000-0003-2109-9874" }, { "id": "Morino-Isamu", "name": { "family": "Morino", "given": "Isamu" }, "orcid": "0000-0003-2720-1569" }, { "id": "Notholt-Justus", "name": { "family": "Notholt", "given": "Justus" }, "orcid": "0000-0002-3324-885X" }, { "id": "Shiomi-Kei", "name": { "family": "Shiomi", "given": "Kei" }, "orcid": "0000-0002-1206-8614" }, { "id": "Strong-Kim", "name": { "family": "Strong", "given": "Kim" }, "orcid": "0000-0001-9947-1053" }, { "id": "Kivi-Rigel", "name": { "family": "Kivi", "given": "Rigel" }, "orcid": "0000-0001-8828-2759" }, { "id": "Buschmann-Matthias", "name": { "family": "Buschmann", "given": "Matthias" }, "orcid": "0000-0001-5077-9524" }, { "id": "Deutscher-Nicholas", "name": { "family": "Deutscher", "given": "Nicholas" }, "orcid": "0000-0002-2906-2577" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul" }, "orcid": "0000-0002-6126-3854" }, { "id": "Sussmann-Ralf", "name": { "family": "Sussmann", "given": "Ralf" } }, { "id": "Velazco-Voltaire-A", "name": { "family": "Velazco", "given": "Voltaire A." }, "orcid": "0000-0002-1376-438X" }, { "id": "T\u00e9-Yao", "name": { "family": "T\u00e9", "given": "Yao" }, "orcid": "0000-0001-6405-8074" } ] }, "title": "Characteristics of interannual variability in space-based XCO\u2082 global observations", "ispublished": "pub", "full_text_status": "public", "keywords": "Atmospheric Science", "note": "\u00a9 Author(s) 2023. This work is distributed under the Creative Commons Attribution 4.0 License. \n\nThe authors thank the participants of the NASA OCO-2 mission for providing the OCO-2 data product (from the GES DISC archive: https://disc.gsfc.nasa.gov/datasets/OCO2_L2_Lite_FP_10r/summary, last access: 1 March 2022) used in this study. We thank the TCCON partners for providing total column data. The Paris TCCON site has received funding from Sorbonne Universit\u00e9, the French research center CNRS, the French space agency CNES, and R\u00e9gion \u00cele-de-France. TCCON sites at Tsukuba, Rikubetsu, and Burgos are supported in part by the GOSAT series project. Burgos is supported in part by the Energy Development Corp. Philippines, and the TCCON site at R\u00e9union has been operated by the Royal Belgian Institute for Space Aeronomy with financial support since 2014 by the EU project ICOS-Inwire and the ministerial decree for ICOS (FR/35/IC1 to FR/35/C6) and local activities supported by LACy/UMR8105 and by OSU-R/UMS3365 \u2013 Universit\u00e9 de La R\u00e9union. The TCCON stations at Garmisch and Zugspitze have been supported by the Helmholtz Society via the research program \"Changing Earth \u2013 Sustaining our Future\". The Eureka TCCON measurements were made at the Polar Environment Atmospheric Research Laboratory (PEARL) by the Canadian Network for the Detection of Atmospheric Change (CANDAC), primarily supported by the Natural Sciences and Engineering Research Council of Canada, Environment and Climate Change Canada, and the Canadian Space Agency. \n\nThis research was funded by NASA Awards (grant nos. 80NSSC18K0900 and 80NSSC21K1070) to the University of Michigan and (grant nos. 80NSSC18K0897 and 80NSSC21K1071) to the University of Virginia. \n\nData availability: The version 10 OCO-2 level-2 bias-corrected XCO2 data product is available from the Goddard Earth Sciences Data and Information Services Center Archive: https://disc.gsfc.nasa.gov/datasets/OCO2_L2_Lite_FP_10r/summary (GES DISC, 2022). TCCON data are publicly available from the TCCON data archive (https://doi.org/10.14291/TCCON.GGG2014, Total Carbon Column Observing Network (TCCON) Team, 2017) hosted by the California Institute of Technology. MBL dry-air mole-fraction data are available from the NOAA Global Monitoring Laboratory Earth System Research Laboratories Archive: https://doi.org/10.15138/YAF1-BK21 (https://gml.noaa.gov/ccgg/mbl/data.php, last access: 17 February 2023, NOAA GML CCGG Group, 2019). GOSAT observation datasets are available to the public at the NIES GOSAT website (https://www.gosat.nies.go.jp/en/about_5_products.html, JAXA et al., 2022). \n\nThe supplement related to this article is available online at: https://doi.org/10.5194/acp-23-5355-2023-supplement. \n\nAuthor contributions: Formal analysis: YG. Writing \u2013 original draft preparation: YG. Conceptualization: GKA. Supervision: GKA. Project administration: GKA and SCD. Writing \u2013 review and editing: GKA, SCD, CP, DP, DW, FH, HO, IM, JN, KeS, KiS, KR, MB, ND, PW, RS, VAV, and YT. \n\nThe contact author has declared that none of the authors has any competing interests.\n\n
Published - acp-23-5355-2023.pdf
Supplemental Material - acp-23-5355-2023-supplement.pdf
", "abstract": "Atmospheric carbon dioxide (CO\u2082) accounts for the largest radiative forcing among anthropogenic greenhouse gases. There is, therefore, a pressing need to understand the rate at which CO\u2082 accumulates in the atmosphere, including the interannual variations (IAVs) in this rate. IAV in the CO\u2082 growth rate is a small signal relative to the long-term trend and the mean annual cycle of atmospheric CO\u2082, and IAV is tied to climatic variations that may provide insights into long-term carbon\u2013climate feedbacks. Observations from the Orbiting Carbon Observatory-2 (OCO-2) mission offer a new opportunity to refine our understanding of atmospheric CO\u2082 IAV since the satellite can measure over remote terrestrial regions and the open ocean, where traditional in situ CO\u2082 monitoring is difficult, providing better spatial coverage compared to ground-based monitoring techniques. In this study, we analyze the IAV of column-averaged dry-air CO\u2082 mole fraction (XCO\u2082) from OCO-2 between September 2014 and June 2021. The amplitude of the IAV, which is calculated as the standard deviation of the time series, is up to 1.2\u2009ppm over the continents and around 0.4\u2009ppm over the open ocean. Across all latitudes, the OCO-2-detected XCO\u2082 IAV shows a clear relationship with El Ni\u00f1o\u2013Southern Oscillation (ENSO)-driven variations that originate in the tropics and are transported poleward. Similar, but smoother, zonal patterns of OCO-2 XCO\u2082 IAV time series compared to ground-based in situ observations and with column observations from the Total Carbon Column Observing Network (TCCON) and the Greenhouse Gases Observing Satellite (GOSAT) show that OCO-2 observations can be used reliably to estimate IAV. Furthermore, the extensive spatial coverage of the OCO-2 satellite data leads to smoother IAV time series than those from other datasets, suggesting that OCO-2 provides new capabilities for revealing small IAV signals despite sources of noise and error that are inherent to remote-sensing datasets.", "date": "2023-05-12", "date_type": "published", "publication": "Atmospheric Chemistry and Physics", "volume": "23", "number": "9", "publisher": "European Geosciences Union", "pagerange": "5355-5372", "id_number": "CaltechAUTHORS:20230615-813000000.35", "issn": "1680-7324", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230615-813000000.35", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "80NSSC18K0900" }, { "agency": "NASA", "grant_number": "80NSSC21K1070" }, { "agency": "NASA", "grant_number": "80NSSC18K0897" }, { "agency": "NASA", "grant_number": "80NSSC21K1071" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/acp-23-5355-2023", "primary_object": { "basename": "acp-23-5355-2023-supplement.pdf", "url": "https://authors.library.caltech.edu/records/vzqd9-96j05/files/acp-23-5355-2023-supplement.pdf" }, "related_objects": [ { "basename": "acp-23-5355-2023.pdf", "url": "https://authors.library.caltech.edu/records/vzqd9-96j05/files/acp-23-5355-2023.pdf" } ], "resource_type": "article", "pub_year": "2023", "author_list": "Guan, Yifan; Keppel-Aleks, Gretchen; et el." }, { "id": "https://authors.library.caltech.edu/records/qd3z8-a5d39", "eprint_id": 121303, "eprint_status": "archive", "datestamp": "2023-08-22 20:26:45", "lastmod": "2023-10-23 20:34:43", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Murphy-Sara-E", "name": { "family": "Murphy", "given": "Sara E." }, "orcid": "0000-0002-8226-9446" }, { "id": "Crounse-John-D", "name": { "family": "Crounse", "given": "John D." }, "orcid": "0000-0001-5443-729X" }, { "id": "M\u00f8ller-Kristian-H", "name": { "family": "M\u00f8ller", "given": "Kristian H." }, "orcid": "0000-0001-8070-8516" }, { "id": "Rezgui-Samir-P", "name": { "family": "Rezgui", "given": "Samir P." } }, { "id": "Hafeman-Nicholas-J", "name": { "family": "Hafeman", "given": "Nicholas J." }, "orcid": "0000-0001-7525-7597" }, { "id": "Park-James", "name": { "family": "Park", "given": "James" } }, { "id": "Kjaergaard-Henrik-G", "name": { "family": "Kjaergaard", "given": "Henrik G." }, "orcid": "0000-0002-7275-8297" }, { "id": "Stoltz-B-M", "name": { "family": "Stoltz", "given": "Brian M." }, "orcid": "0000-0001-9837-1528" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "Accretion product formation in the self-reaction of ethene-derived hydroxy peroxy radicals", "ispublished": "pub", "full_text_status": "public", "keywords": "Pollution; Environmental Chemistry; Chemistry (miscellaneous); Analytical Chemistry", "note": "\u00a9 2023 The Author(s). Published by the Royal Society of Chemistry. This article is licensed under a Creative Commons Attribution 3.0 Unported Licence. \n \nThis material is based upon work supported by the U. S. National Science Foundation under Grant No. CHE-1905340. This work was also supported by Novo Nordisk Foundation Grant NNF19OC0057374. \n\nThere are no conflicts to declare.\n\nIn Press - d3ea00020f.pdf
", "abstract": "In this study we revisit one of the simplest RO\u2082\u2022 + RO\u2082\u2022 reactions: the self-reaction of the ethene-derived hydroxyperoxy radical formed via sequential addition of \u2022OH and O\u2082 to ethene. Previous studies of this reaction suggested that the branching to 'accretion products', compounds containing the carbon backbone of both reactants, was minimal. Here, CF\u2083O\u207b GC-CIMS is used to quantify the yields of ethylene glycol, glycolaldehyde, a hydroxy hydroperoxide produced from RO\u2082\u2022 + RO\u2082\u2022, and a C\u2084O\u2084H\u2081\u2080\naccretion product. These experiments were performed in an environmental chamber at 993 hPa and 294 K. We provide evidence that the accretion product is likely dihydroxy diethyl peroxide (HOC\u2082H\u2084OOC\u2082H\u2084OH=ROOR) and forms in the gas-phase with a branching fraction of 23 \u00b1 5%. We suggest a new channel in the RO\u2082\u2022 + RO\u2082\u2022 chemistry leading directly to the formation of HO\u2082 (together with glycolaldehyde and an alkoxy radical). Finally, by varying the ratio of the formation rate of RO\u2082 and HO\u2082 in our chamber, we constrain the ratio of the rate coefficient for the reaction of RO\u2082\u2022 + RO\u2082\u2022 to that of RO\u2082\u2022 + HO\u2082\u2022 and find that this ratio is 0.22 \u00b1 0.07, consistent with previous flash photolysis studies.", "date": "2023-05-05", "date_type": "published", "publication": "Environmental Science: Atmospheres", "publisher": "Royal Society of Chemistry", "id_number": "CaltechAUTHORS:20230502-761654700.2", "issn": "2634-3606", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230502-761654700.2", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "CHE-1905340" }, { "agency": "Novo Nordisk Foundation", "grant_number": "NNF19OC0057374" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1039/d3ea00020f", "primary_object": { "basename": "d3ea00020f.pdf", "url": "https://authors.library.caltech.edu/records/qd3z8-a5d39/files/d3ea00020f.pdf" }, "resource_type": "article", "pub_year": "2023", "author_list": "Murphy, Sara E.; Crounse, John D.; et el." }, { "id": "https://authors.library.caltech.edu/records/tzfcq-dyg80", "eprint_id": 118898, "eprint_status": "archive", "datestamp": "2023-08-22 18:28:24", "lastmod": "2023-10-24 23:31:59", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Rickly-Pamela-S", "name": { "family": "Rickly", "given": "Pamela S." }, "orcid": "0000-0002-8459-869X" }, { "name": { "family": "Guo", "given": "Hongyu" }, "orcid": "0000-0003-0487-3610" }, { "name": { "family": "Campuzano-Jost", "given": "Pedro" }, "orcid": "0000-0003-3930-010X" }, { "name": { "family": "Jimenez", "given": "Jose L." }, "orcid": "0000-0001-6203-1847" }, { "name": { "family": "Wolfe", "given": "Glenn M." }, "orcid": "0000-0001-6586-4043" }, { "name": { "family": "Bennett", "given": "Ryan" } }, { "name": { "family": "Bourgeois", "given": "Ilann" }, "orcid": "0000-0002-2875-1258" }, { "id": "Crounse-John-D", "name": { "family": "Crounse", "given": "John D." }, "orcid": "0000-0001-5443-729X" }, { "name": { "family": "Dibb", "given": "Jack E." }, "orcid": "0000-0003-3096-7709" }, { "name": { "family": "DiGangi", "given": "Joshua P." }, "orcid": "0000-0002-6764-8624" }, { "name": { "family": "Diskin", "given": "Glenn S." }, "orcid": "0000-0002-3617-0269" }, { "name": { "family": "Dollner", "given": "Maximilian" }, "orcid": "0000-0002-9196-4969" }, { "name": { "family": "Gargulinski", "given": "Emily M." }, "orcid": "0000-0002-3949-6627" }, { "name": { "family": "Hall", "given": "Samuel R." }, "orcid": "0000-0002-2060-7112" }, { "name": { "family": "Halliday", "given": "Hannah S." }, "orcid": "0000-0001-9499-9836" }, { "name": { "family": "Hanisco", "given": "Thomas F." }, "orcid": "0000-0001-9434-8507" }, { "name": { "family": "Hannun", "given": "Reem A." }, "orcid": "0000-0001-5195-5307" }, { "name": { "family": "Liao", "given": "Jin" } }, { "name": { "family": "Moore", "given": "Richard" }, "orcid": "0000-0003-2911-4469" }, { "name": { "family": "Nault", "given": "Benjamin A." }, "orcid": "0000-0001-9464-4787" }, { "name": { "family": "Nowak", "given": "John B." }, "orcid": "0000-0002-5697-9807" }, { "name": { "family": "Peischl", "given": "Jeff" }, "orcid": "0000-0002-9320-7101" }, { "name": { "family": "Robinson", "given": "Claire E." } }, { "name": { "family": "Ryerson", "given": "Thomas" }, "orcid": "0000-0003-2800-7581" }, { "name": { "family": "Sanchez", "given": "Kevin J." }, "orcid": "0000-0003-4456-0918" }, { "name": { "family": "Sch\u00f6berl", "given": "Manuel" }, "orcid": "0000-0002-8448-3454" }, { "name": { "family": "Soja", "given": "Amber J." }, "orcid": "0000-0001-8637-3040" }, { "name": { "family": "St. Clair", "given": "Jason M." }, "orcid": "0000-0002-9367-5749" }, { "name": { "family": "Thornhill", "given": "Kenneth L." }, "orcid": "0000-0002-8920-4346" }, { "name": { "family": "Ullmann", "given": "Kirk" }, "orcid": "0000-0002-4724-9634" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" }, { "name": { "family": "Weinzierl", "given": "Bernadett" }, "orcid": "0000-0003-4555-5686" }, { "name": { "family": "Wiggins", "given": "Elizabeth B." }, "orcid": "0000-0003-1559-4502" }, { "name": { "family": "Winstead", "given": "Edward L." }, "orcid": "0000-0001-9451-2303" }, { "name": { "family": "Rollins", "given": "Andrew W." }, "orcid": "0000-0002-1020-3966" } ] }, "title": "Emission factors and evolution of SO\u2082 measured from biomass burning in wildfires and agricultural fires", "ispublished": "pub", "full_text_status": "public", "keywords": "Atmospheric Science", "note": "Pamela S. Rickly and Andrew W. Rollins acknowledge support from NASA's Upper Atmosphere Composition Observations program. Maximilian Dollner, Manuel Sch\u00f6berl, and Bernadett Weinzierl have received funding from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation framework program under grant agreement no. 640458 (A-LIFE) and from the University of Vienna. Hongyu Guo, Pedro Campuzano-Jost, and Jose L. Jimenez were supported by NASA 80NSSC18K0630 and 80NSSC21K1451 and NSF AGS-1822664. Glenn M. Wolfe, Thomas F. Hanisco, Reem A. Hannun, Jason M. St. Clair, and Jin Liao acknowledge support from the NASA Tropospheric Composition program and the NOAA AC4 program (NA17OAR4310004). Samuel R. Hall and Kirk Ullmann are funded under NASA grant 80NSSC18K0638. The National Center for Atmospheric Research is sponsored by the National Science Foundation. We would like to thank the NASA DC-8 crew and management team for support during FIREX-AQ integration and flights. Data from FIREX-AQ are available at https://www-air.larc.nasa.gov/cgi-bin/ArcView/firexaq (last access: 1 October 2021).\n\nThis research has been supported by the National Aeronautics and Space Administration (grant no. 20-UACO20-0021).", "abstract": "Fires emit sufficient sulfur to affect local and regional air quality and climate. This study analyzes SO\u2082 emission factors and variability in smoke plumes from US wildfires and agricultural fires, as well as their relationship to sulfate and hydroxymethanesulfonate (HMS) formation. Observed SO\u2082 emission factors for various fuel types show good agreement with the latest reviews of biomass burning emission factors, producing an emission factor range of 0.47\u20131.2\u2009g\u2009SO\u2082\u2009kg\u207b\u00b9\u2009C. These emission factors vary with geographic location in a way that suggests that deposition of coal burning emissions and application of sulfur-containing fertilizers likely play a role in the larger observed values, which are primarily associated with agricultural burning. A 0-D box model generally reproduces the observed trends of SO\u2082 and total sulfate (inorganic + organic) in aging wildfire plumes. In many cases, modeled HMS is consistent with the observed organosulfur concentrations. However, a comparison of observed organosulfur and modeled HMS suggests that multiple organosulfur compounds are likely responsible for the observations but that the chemistry of these compounds yields similar production and loss rates as that of HMS, resulting in good agreement with the modeled results. We provide suggestions for constraining the organosulfur compounds observed during these flights, and we show that the chemistry of HMS can allow organosulfur to act as an S(IV) reservoir under conditions of pH\u2009>\u20096 and liquid water content >10\u207b\u2077\u2009g\u2009sm\u207b\u00b3. This can facilitate long-range transport of sulfur emissions, resulting in increased SO\u2082 and eventually sulfate in transported smoke.", "date": "2022-12-13", "date_type": "published", "publication": "Atmospheric Chemistry and Physics", "volume": "22", "number": "23", "publisher": "European Geosciences Union", "pagerange": "15603-15620", "id_number": "CaltechAUTHORS:20230123-451320900.31", "issn": "1680-7324", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230123-451320900.31", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "European Research Council (ERC)", "grant_number": "640458" }, { "agency": "NASA", "grant_number": "80NSSC18K0630" }, { "agency": "NASA", "grant_number": "80NSSC21K1451" }, { "agency": "NSF", "grant_number": "AGS-1822664" }, { "agency": "National Oceanic and Atmospheric Administration (NOAA)", "grant_number": "NA17OAR4310004" }, { "agency": "NASA", "grant_number": "80NSSC18K0638" }, { "agency": "NASA", "grant_number": "20-UACO20-0021" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/acp-22-15603-2022", "resource_type": "article", "pub_year": "2022", "author_list": "Rickly, Pamela S.; Guo, Hongyu; et el." }, { "id": "https://authors.library.caltech.edu/records/byw9t-f2d23", "eprint_id": 119414, "eprint_status": "archive", "datestamp": "2023-08-22 18:26:11", "lastmod": "2023-10-25 14:39:54", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Zhang-Xuan", "name": { "family": "Zhang", "given": "Xuan" }, "orcid": "0000-0002-7203-2293" }, { "id": "Wang-Siyuan", "name": { "family": "Wang", "given": "Siyuan" }, "orcid": "0000-0002-8110-5714" }, { "id": "Apel-Eric-C", "name": { "family": "Apel", "given": "Eric C." }, "orcid": "0000-0001-9421-818X" }, { "id": "Schwantes-Rebecca-H", "name": { "family": "Schwantes", "given": "Rebecca H." }, "orcid": "0000-0002-7095-3718" }, { "id": "Hornbrook-Rebecca-S", "name": { "family": "Hornbrook", "given": "Rebecca S." }, "orcid": "0000-0002-6304-6554" }, { "id": "Hills-Alan-J", "name": { "family": "Hills", "given": "Alan J." }, "orcid": "0000-0001-9460-4080" }, { "id": "DeMarsh-Kate-E", "name": { "family": "DeMarsh", "given": "Kate E." } }, { "id": "Moo-Zeyi", "name": { "family": "Moo", "given": "Zeyi" } }, { "id": "Ortega-John", "name": { "family": "Ortega", "given": "John" }, "orcid": "0000-0002-6270-6370" }, { "id": "Brune-William-H", "name": { "family": "Brune", "given": "William H." }, "orcid": "0000-0002-1609-4051" }, { "id": "Mauldin-Roy-L-III", "name": { "family": "Mauldin", "given": "Roy L., III" }, "orcid": "0000-0002-8569-8561" }, { "id": "Cantrell-Christopher-A", "name": { "family": "Cantrell", "given": "Christopher A." }, "orcid": "0000-0002-3844-1560" }, { "id": "Teng-Alexander-P", "name": { "family": "Teng", "given": "Alexander P." }, "orcid": "0000-0002-6434-0501" }, { "id": "Blake-Donald-R", "name": { "family": "Blake", "given": "Donald R." }, "orcid": "0000-0002-8283-5014" }, { "id": "Campos-Teresa", "name": { "family": "Campos", "given": "Teresa" }, "orcid": "0000-0002-7226-3569" }, { "id": "Daube-Bruce-C-Jr", "name": { "family": "Daube", "given": "Bruce" }, "orcid": "0000-0002-6839-2296" }, { "id": "Emmons-Louisa-K", "name": { "family": "Emmons", "given": "Louisa K." }, "orcid": "0000-0003-2325-6212" }, { "id": "Hall-Samuel-R", "name": { "family": "Hall", "given": "Samuel R." }, "orcid": "0000-0002-2060-7112" }, { "id": "Ullmann-Kirk", "name": { "family": "Ullmann", "given": "Kirk" }, "orcid": "0000-0002-4724-9634" }, { "id": "Wofsy-Steven-C", "name": { "family": "Wofsy", "given": "Steven C." }, "orcid": "0000-0002-3990-6737" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Tyndall-Geoffrey-S", "name": { "family": "Tyndall", "given": "Geoffrey S." }, "orcid": "0000-0002-0695-5241" }, { "id": "Orlando-John-J", "name": { "family": "Orlando", "given": "John J." }, "orcid": "0000-0003-2879-0844" } ] }, "title": "Probing isoprene photochemistry at atmospherically relevant nitric oxide levels", "ispublished": "pub", "full_text_status": "public", "keywords": "Materials Chemistry; Biochemistry (medical); General Chemical Engineering; Environmental Chemistry; Biochemistry; General Chemistry", "note": "\u00a9 2022 Elsevier. \n\nThe work was supported by the US National Science Foundation grant AGS-2131199. The National Center for Atmospheric Research is operated by the University Corporation for Atmospheric Research under the sponsorship of the US National Science Foundation. Siyuan Wang and Rebecca H. Schwantes were supported in part by the NOAA Cooperative Agreement with the Cooperative Institute for Research in Environmental Sciences, NA17OAR4320101. Kirk Ullmann (Atmospheric Chemistry Observations & Modeling Laboratory, National Center for Atmospheric Research) is acknowledged for the photolysis frequency measurements via the Actinic Flux Spectroradiometer. Ilann Bourgeois, Jeff Peischl, Thomas B. Ryerson, and Chelsea Thompson (Earth System Research Laboratory, National Oceanic and Atmospheric Administration) are acknowledged for the measurements of NO\u1d67 and O\u2083. Glenn S. Diskin (Langley Research Center, National Aeronautics and Space Administration) is acknowledged for the water vapor measurements by the Diode Laser Hygrometer. Thomas F. Hanisco and Jason M. St. Clair (Goddard Space Flight Center, National Aeronautics and Space Administration) are acknowledged for the in situ Airborne Formaldehyde measurements. Kathryn McKain (Earth System Research Laboratory, National Oceanic and Atmospheric Administration) is acknowledged for the methane and carbon monoxide measurements by the Wavelength-Scanned Cavity Ring Down Spectroscopy. \n\nAuthor contributions. X.Z., P.O.W., G.S.T., and J.J.O. designed the study; X.Z. and J.O. performed the chamber experiments; E.C.A., R.S.H., A.J.H., W.H.B., R.L.M., C.A.C., D.R.B., T.C., B.D., S.R.H., and S.C.W. performed aircraft measurements; X.Z., Z.M., K.E.D., A.P.T., G.S.T., and J.J.O. analyzed the data; S.W., R.H.S. and L.K.E. performed model simulations; X.Z., S.W., Z.M., K.E.D., and R.H.S. prepared the figures; and X.Z., G.S.T., and J.J.O. wrote the manuscript. \n\nData and code availability. All data and codes are available from the lead contact upon request. \n\nThe authors declare no competing interests.\n\nSupplemental Material - 1-s2.0-S2451929422004156-mmc1.pdf
", "abstract": "he reactive chemistry of isoprene, which is the dominant hydrocarbon in biogenic emissions, has a controlling influence on the composition and cleansing capacity of the global atmosphere. Despite decades of research, isoprene continues to offer surprises in its atmospheric chemistry, particularly in environments with low-to-moderate levels of nitrogen oxides (NO\u2093). Here, we probe the isoprene photochemical oxidation in this \"intermediate-NO\u2093\" regime by examining the yield distributions of two major oxidation products, i.e., methacrolein and methyl vinyl ketone, using chamber experiments and aircraft measurements. Such a dataset provides strong constraints on the kinetics of the isoprene peroxy radical interconversion\u2014a newly discovered mechanism that essentially governs the isoprene oxidation carbon flow. Insights from measurement-model comparisons further reveal an efficient operation of this mechanism across all the vegetated continents over the globe, constantly modulating the radical cycling and contributing to the formation of ozone and organic aerosols in the atmosphere.", "date": "2022-12-08", "date_type": "published", "publication": "Chem", "volume": "8", "number": "12", "publisher": "Cell Press", "pagerange": "3225-3240", "id_number": "CaltechAUTHORS:20230221-19480300.55", "issn": "2451-9294", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230221-19480300.55", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "AGS-2131199" }, { "agency": "National Oceanic and Atmospheric Administration (NOAA)", "grant_number": "NA17OAR4320101" } ] }, "doi": "10.1016/j.chempr.2022.08.003", "primary_object": { "basename": "1-s2.0-S2451929422004156-mmc1.pdf", "url": "https://authors.library.caltech.edu/records/byw9t-f2d23/files/1-s2.0-S2451929422004156-mmc1.pdf" }, "resource_type": "article", "pub_year": "2022", "author_list": "Zhang, Xuan; Wang, Siyuan; et el." }, { "id": "https://authors.library.caltech.edu/records/negpx-p8510", "eprint_id": 118053, "eprint_status": "archive", "datestamp": "2023-08-22 18:11:55", "lastmod": "2023-10-24 23:13:17", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Wu-Dien", "name": { "family": "Wu", "given": "Dien" }, "orcid": "0000-0002-2915-5335" }, { "id": "Liu-Junjie", "name": { "family": "Liu", "given": "Junjie" }, "orcid": "0000-0002-7184-6594" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Palmer-Paul-I", "name": { "family": "Palmer", "given": "Paul I." }, "orcid": "0000-0002-1487-0969" }, { "id": "Nelson-Robert-R", "name": { "family": "Nelson", "given": "Robert R." }, "orcid": "0000-0002-3471-5683" }, { "id": "Kiel-Matth\u00e4us", "name": { "family": "Kiel", "given": "Matth\u00e4us" }, "orcid": "0000-0002-9784-962X" }, { "id": "Eldering-Annmarie", "name": { "family": "Eldering", "given": "Annmarie" }, "orcid": "0000-0003-1080-9922" } ] }, "title": "Towards sector-based attribution using intra-city variations in satellite-based emission ratios between CO\u2082 and CO", "ispublished": "pub", "full_text_status": "public", "keywords": "Atmospheric Science", "note": "The production of the OCO-3 science data products used 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 (prime contract number 80NM0018D0004). The research effort was funded by the Jet Propulsion Laboratory Research and Technology Development project R.21.023.106. The analysis was supported by the W. M. Keck Institute for Space Studies and by the National Aeronautics and Space Administration (grant no. 80NSSC21k1064).", "abstract": "Carbon dioxide (CO\u2082) and air pollutants such as carbon monoxide (CO) are co-emitted by many combustion sources. Previous efforts have combined satellite-based observations of multiple tracers to calculate their emission ratio (ER) for inferring combustion efficiency at the regional to city scale. Very few studies have focused on combustion efficiency at the sub-city scale or related it to emission sectors using space-based observations. Several factors are important for interpreting and deriving spatially resolved ERs from asynchronous satellite measurements, including (1) variations in meteorological conditions given the mismatch in satellite overpass times, (2) differences in vertical sensitivity of the retrievals (i.e., averaging kernel profiles), (3) interferences from the biosphere and biomass burning, and (4) the mismatch in the daytime variations of CO and CO\u2082 emissions. In this study, we extended an established emission estimate approach to arrive at spatially resolved ERs based on retrieved column-averaged CO\u2082 (XCO\u2082) from the Snapshot Area Mapping (SAM) mode of the Orbiting Carbon Observatory-3 (OCO-3) and column-averaged CO from the TROPOspheric Monitoring Instrument (TROPOMI).\n\nTo evaluate the influences of the confounding factors listed above and further attribute intra-urban variations in ERs to certain sectors, we leveraged a Lagrangian atmospheric transport model with an urban land cover classification dataset and reported ER_(CO) values from the sounding level to the overpass and city level. We found that the differences in overpass times and averaging kernels between OCO and TROPOMI strongly affect the estimated spatially resolved ER_(CO). Specifically, a time difference of >3\u2009h typically led to dramatic changes in wind directions and urban plume shapes, thereby making the calculation of accurate sounding-specific ERCO difficult. After removing such cases from consideration and applying a simple plume shift method when necessary to account for changes in wind direction and speed, we discovered significant contrasts in combustion efficiencies between (1) two megacities versus two industry-oriented cities and (2) different regions within a city, based on six nearly coincident overpasses per city. Results suggest that the ER_(CO) impacted by heavy industry in Los Angeles is slightly lower than the overall city-wide value (<10\u2009ppb-COppm-CO\u2082). In contrast, the ER_(CO) related to heavy industry in Shanghai is much higher than Shanghai's city mean and more aligned with the city means of two selected industry-oriented cities in China (approaching 20\u2009ppb-COppm-CO\u2082). Although investigations based on a larger number of satellite overpasses are needed, our unique approach (i.e., without using sector-specific information from emission inventories) provides new insights into assessing combustion efficiency within a city from future satellite missions, such as those that will map column CO\u2082 and CO concentrations simultaneously with high spatiotemporal resolutions.", "date": "2022-11-16", "date_type": "published", "publication": "Atmospheric Chemistry and Physics", "volume": "22", "number": "22", "publisher": "European Geosciences Union", "pagerange": "14547-14570", "id_number": "CaltechAUTHORS:20221128-494241100.8", "issn": "1680-7324", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20221128-494241100.8", "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 Research and Technology Development Fund", "grant_number": "R.21.023.106" }, { "agency": "NASA", "grant_number": "80NSSC21k1064" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/acp-22-14547-2022", "resource_type": "article", "pub_year": "2022", "author_list": "Wu, Dien; Liu, Junjie; et el." }, { "id": "https://authors.library.caltech.edu/records/avwtz-dqh02", "eprint_id": 116713, "eprint_status": "archive", "datestamp": "2023-08-22 17:27:18", "lastmod": "2023-10-24 21:09:32", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Bourgeois-Ilann", "name": { "family": "Bourgeois", "given": "Ilann" }, "orcid": "0000-0002-2875-1258" }, { "name": { "family": "Peischl", "given": "Jeff" }, "orcid": "0000-0002-9320-7101" }, { "name": { "family": "Neuman", "given": "J. Andrew" }, "orcid": "0000-0002-3986-1727" }, { "name": { "family": "Brown", "given": "Steven S." }, "orcid": "0000-0001-7477-9078" }, { "id": "Allen-Hannah-M", "name": { "family": "Allen", "given": "Hannah M." }, "orcid": "0000-0002-4218-5133" }, { "name": { "family": "Campuzano-Jost", "given": "Pedro" }, "orcid": "0000-0003-3930-010X" }, { "name": { "family": "Coggon", "given": "Matthew M." }, "orcid": "0000-0002-5763-1925" }, { "name": { "family": "DiGangi", "given": "Joshua P." }, "orcid": "0000-0002-6764-8624" }, { "name": { "family": "Diskin", "given": "Glenn S." }, "orcid": "0000-0002-3617-0269" }, { "name": { "family": "Gilman", "given": "Jessica B." }, "orcid": "0000-0002-7899-9948" }, { "name": { "family": "Gkatzelis", "given": "Georgios I." }, "orcid": "0000-0002-4608-3695" }, { "name": { "family": "Guo", "given": "Hongyu" }, "orcid": "0000-0003-0487-3610" }, { "name": { "family": "Halliday", "given": "Hannah A." }, "orcid": "0000-0001-9499-9836" }, { "name": { "family": "Hanisco", "given": "Thomas F." }, "orcid": "0000-0001-9434-8507" }, { "name": { "family": "Holmes", "given": "Christopher D." }, "orcid": "0000-0002-2727-0954" }, { "name": { "family": "Huey", "given": "L. Gregory" }, "orcid": "0000-0002-0518-7690" }, { "name": { "family": "Jimenez", "given": "Jose L." }, "orcid": "0000-0001-6203-1847" }, { "name": { "family": "Lamplugh", "given": "Aaron D." } }, { "name": { "family": "Lee", "given": "Young Ro" } }, { "name": { "family": "Lindaas", "given": "Jakob" }, "orcid": "0000-0003-1872-3162" }, { "name": { "family": "Moore", "given": "Richard H." }, "orcid": "0000-0003-2911-4469" }, { "name": { "family": "Nault", "given": "Benjamin A." }, "orcid": "0000-0001-9464-4787" }, { "name": { "family": "Nowak", "given": "John B." }, "orcid": "0000-0002-5697-9807" }, { "name": { "family": "Pagonis", "given": "Demetrios" } }, { "name": { "family": "Rickly", "given": "Pamela S." }, "orcid": "0000-0002-8459-869X" }, { "name": { "family": "Robinson", "given": "Michael A." }, "orcid": "0000-0003-0977-9148" }, { "id": "Rollins-Andrew-M", "name": { "family": "Rollins", "given": "Andrew M." } }, { "name": { "family": "Selimovic", "given": "Vanessa" } }, { "name": { "family": "St. Clair", "given": "Jason M." }, "orcid": "0000-0002-9367-5749" }, { "name": { "family": "Tanner", "given": "David" } }, { "id": "Vasquez-Krystal-T", "name": { "family": "Vasquez", "given": "Krystal T." }, "orcid": "0000-0003-4540-4212" }, { "name": { "family": "Veres", "given": "Patrick R." }, "orcid": "0000-0001-7539-353X" }, { "name": { "family": "Warneke", "given": "Carsten" }, "orcid": "0000-0003-3811-8496" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" }, { "name": { "family": "Washenfelder", "given": "Rebecca A." }, "orcid": "0000-0002-8106-3702" }, { "name": { "family": "Wiggins", "given": "Elizabeth B." } }, { "name": { "family": "Womack", "given": "Caroline C." }, "orcid": "0000-0002-7101-9054" }, { "id": "Xu-Lu", "name": { "family": "Xu", "given": "Lu" }, "orcid": "0000-0002-0021-9876" }, { "name": { "family": "Zarzana", "given": "Kyle J." }, "orcid": "0000-0003-1581-6419" }, { "name": { "family": "Ryerson", "given": "Thomas B." }, "orcid": "0000-0003-2800-7581" } ] }, "title": "Comparison of airborne measurements of NO, NO\u2082, HONO, No_y, and CO during FIREX-AQ", "ispublished": "pub", "full_text_status": "public", "keywords": "Atmospheric Science", "note": "We would like to thank the NOAA/NASA FIREX-AQ science and aircraft operation teams. We acknowledge Armin Whistaler, Felix Piel, and Laura Tomsche for providing the NH3 measurements from FIREX-AQ. We thank Ann Middlebrook for helpful discussion regarding pNO3 sampling in the NOy inlet and AMS performance.\n\nThis research has been supported by the National Oceanic and Atmospheric Administration (grant nos. NA17OAR4320101, NA16OAR4310100, and NA17OAR4310004) and the National Aeronautics and Space Administration (grant nos. 80NSSC18K0660 and 80NSSC18K0630).", "abstract": "We present a comparison of fast-response instruments installed onboard the NASA DC-8 aircraft that measured nitrogen oxides (NO and NO\u2082), nitrous acid (HONO), total reactive odd nitrogen (measured both as the total (NO_y) and from the sum of individually measured species (\u03a3NO_y)), and carbon monoxide (CO) in the troposphere during the 2019 Fire Influence on Regional to Global Environments and Air Quality (FIREX-AQ) campaign. By targeting smoke from summertime wildfires, prescribed fires, and agricultural burns across the continental United States, FIREX-AQ provided a\nunique opportunity to investigate measurement accuracy in concentrated\nplumes where hundreds of species coexist. Here, we compare NO measurements\nby chemiluminescence (CL) and laser-induced fluorescence (LIF); NO\u2082 measurements by CL, LIF, and cavity-enhanced spectroscopy (CES); HONO\nmeasurements by CES and iodide-adduct chemical ionization mass spectrometry\n(CIMS); and CO measurements by tunable diode laser absorption spectrometry\n(TDLAS) and integrated cavity output spectroscopy (ICOS). Additionally,\ntotal NO_y measurements using the CL instrument were compared with\n\u03a3NO_y (=\u2009NO\u2009+\u2009NO\u2082\u2009+\u2009HONO\u2009+\u2009nitric acid (HNO\u2083)\u2009+\u2009acyl peroxy nitrates (APNs)\u2009+\u2009submicrometer particulate nitrate\n(pNO\u2083)). Other NO_y species were not included in \u03a3NO_y\nas they either contributed minimally to it (e.g., C\u2081\u2013C\u2085 alkyl\nnitrates, nitryl chloride (ClNO\u2082), dinitrogen pentoxide\n(N\u2082O\u2085)) or were not measured during FIREX-AQ (e.g., higher\noxidized alkyl nitrates, nitrate (NO\u2083), non-acyl peroxynitrates, coarse-mode aerosol nitrate). The aircraft instrument intercomparisons demonstrate\nthe following points: (1)\u00a0NO measurements by CL and LIF agreed well within\ninstrument uncertainties but with potentially reduced time response for the CL instrument; (2)\u00a0NO\u2082 measurements by LIF and CES agreed well within instrument uncertainties, but CL NO\u2082 was on average 10\u2009% higher; (3)\u00a0CES and CIMS HONO measurements were highly correlated in each fire plume transect, but the correlation slope of CES vs. CIMS for all 1\u2009Hz data during\nFIREX-AQ was 1.8, which we attribute to a reduction in the CIMS sensitivity\nto HONO in high-temperature environments; (4)\u00a0NO_y budget closure was\ndemonstrated for all flights within the combined instrument uncertainties of 25\u2009%. However, we used a fluid dynamic flow model to estimate that average pNO\u2083 sampling fraction through the NO_y inlet in smoke was variable from one flight to another and ranged between 0.36 and 0.99, meaning that approximately 0\u2009%\u201324\u2009% on average of the total measured NO_y in smoke\nmay have been unaccounted for and may be due to unmeasured species such as\norganic nitrates; (5)\u00a0CO measurements by ICOS and TDLAS agreed well within\ncombined instrument uncertainties, but with a systematic offset that\naveraged 2.87\u2009ppbv; and (6)\u00a0integrating smoke plumes followed by fitting the integrated values of each plume improved the correlation between independent measurements.", "date": "2022-08-29", "date_type": "published", "publication": "Atmospheric Measurement Techniques", "volume": "15", "number": "16", "publisher": "European Geosciences Union", "pagerange": "4901-4930", "id_number": "CaltechAUTHORS:20220906-252512000", "issn": "1867-8548", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220906-252512000", "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": "NA17OAR4320101" }, { "agency": "National Oceanic and Atmospheric Administration (NOAA)", "grant_number": "NA16OAR4310100" }, { "agency": "National Oceanic and Atmospheric Administration (NOAA)", "grant_number": "NA17OAR4310004" }, { "agency": "NASA", "grant_number": "80NSSC18K0660" }, { "agency": "NASA", "grant_number": "80NSSC18K0630" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/amt-15-4901-2022", "resource_type": "article", "pub_year": "2022", "author_list": "Bourgeois, Ilann; Peischl, Jeff; et el." }, { "id": "https://authors.library.caltech.edu/records/6ea3z-eb661", "eprint_id": 116251, "eprint_status": "archive", "datestamp": "2023-08-22 16:59:45", "lastmod": "2023-10-23 20:08:41", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Schneider-Matthias", "name": { "family": "Schneider", "given": "Matthias" }, "orcid": "0000-0001-8452-0035" }, { "name": { "family": "Ertl", "given": "Benjamin" }, "orcid": "0000-0003-1431-2243" }, { "name": { "family": "Tu", "given": "Qiansi" } }, { "name": { "family": "Diekmann", "given": "Christopher J." }, "orcid": "0000-0002-8961-5241" }, { "name": { "family": "Khosrawi", "given": "Farahnaz" }, "orcid": "0000-0002-0261-7253" }, { "name": { "family": "R\u00f6hling", "given": "Amelie N." }, "orcid": "0000-0002-8259-7343" }, { "name": { "family": "Hase", "given": "Frank" } }, { "name": { "family": "Dubravica", "given": "Darko" } }, { "name": { "family": "Garc\u00eda", "given": "Omaira E." }, "orcid": "0000-0002-8395-6440" }, { "name": { "family": "Sep\u00falveda", "given": "Eliezer" } }, { "name": { "family": "Borsdorff", "given": "Tobias" }, "orcid": "0000-0002-4421-0187" }, { "name": { "family": "Landgraf", "given": "Jochen" }, "orcid": "0000-0002-6069-0598" }, { "name": { "family": "Lorente", "given": "Alba" }, "orcid": "0000-0002-2287-4687" }, { "name": { "family": "Butz", "given": "Andr\u00e9" }, "orcid": "0000-0003-0593-1608" }, { "name": { "family": "Chen", "given": "Huilin" }, "orcid": "0000-0002-1573-6673" }, { "name": { "family": "Kivi", "given": "Rigel" }, "orcid": "0000-0001-8828-2759" }, { "name": { "family": "Laemmel", "given": "Thomas" }, "orcid": "0000-0002-6110-954X" }, { "name": { "family": "Ramonet", "given": "Michel" }, "orcid": "0000-0003-1157-1186" }, { "name": { "family": "Crevoisier", "given": "Cyril" } }, { "name": { "family": "Pernin", "given": "J\u00e9rome" } }, { "name": { "family": "Steinbacher", "given": "Martin" }, "orcid": "0000-0002-7195-8115" }, { "name": { "family": "Meinhardt", "given": "Frank" } }, { "name": { "family": "Strong", "given": "Kimberly" }, "orcid": "0000-0001-9947-1053" }, { "name": { "family": "Wunch", "given": "Debra" }, "orcid": "0000-0002-4924-0377" }, { "name": { "family": "Warneke", "given": "Thorsten" }, "orcid": "0000-0001-5185-3415" }, { "id": "Roehl-Coleen-M", "name": { "family": "Roehl", "given": "Coleen" }, "orcid": "0000-0001-5383-8462" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" }, { "name": { "family": "Morino", "given": "Isamu" }, "orcid": "0000-0003-2720-1569" }, { "name": { "family": "Iraci", "given": "Laura T." }, "orcid": "0000-0002-2859-5259" }, { "name": { "family": "Shiomi", "given": "Kei" }, "orcid": "0000-0002-1206-8614" }, { "name": { "family": "Deutscher", "given": "Nicholas M." }, "orcid": "0000-0002-2906-2577" }, { "name": { "family": "Griffith", "given": "David W. T." }, "orcid": "0000-0002-7986-1924" }, { "name": { "family": "Velazco", "given": "Voltaire A." }, "orcid": "0000-0002-1376-438X" }, { "name": { "family": "Pollard", "given": "David F." }, "orcid": "0000-0001-9923-2984" } ] }, "title": "Synergetic use of IASI profile and TROPOMI total-column level 2 methane retrieval products", "ispublished": "pub", "full_text_status": "public", "keywords": "Atmospheric Science", "note": "\u00a9 Author(s) 2022. This work is distributed under the Creative Commons Attribution 4.0 License. \n\nReceived: 9 February 2021 \u2013 Discussion started: 23 February 2021. Revised: 13 April 2022 \u2013 Accepted: 30 May 2022 \u2013 Published: 29 July 2022. \n\nThis research has largely benefitted from funds of the Deutsche Forschungsgemeinschaft (provided for the two projects MOTIV and TEDDY with IDs/Gesch\u00e4ftszeichen 290612604/GZ:SCHN1126/2-1 and 416767181/GZ:SCHN1126/5-1, respectively) and from support by the European Space Agency in the context the \"Sentinel-5p+Innovation (S5p+I) \u2013 Water Vapour Isotopologues (H2O-ISO)\" activities. Furthermore, we acknowledge funds from the Ministerio de Econom\u00eda y Competividad from Spain for the project INMENSE (CGL2016-80688-P).\n\nAn important part of this work was performed on the supercomputers ForHLR and HoreKa funded by the Ministry of Science, Research and the Arts Baden-W\u00fcrttemberg and by the German Federal Ministry of Education and Research. We also acknowledge the contribution of Teide High-Performance Computing facilities. Teide HPC facilities are provided by the Instituto Tecnol\u00f3gico y de Energ\u00edas Renovables (ITER), S.A (https://teidehpc.iter.es/en/home/, last access: 5 July 2022).\n\nThe TROPOMI data processing was carried out on the Dutch National e-Infrastructure with the support of the SURF cooperative. The presented material contains modified Copernicus data (2017, 2019).\n\nThe Eureka TCCON measurements were made at the Polar Environment Atmospheric Research Laboratory (PEARL) by the Canadian Network for the Detection of Atmospheric Change, primarily supported by NSERC, ECCC, and CSA. The East Trout Lake TCCON station is supported by CFI, ORF, and NSERC. The Karlsruhe TCCON station has been supported by the German Bundesministerium f\u00fcr Wirtschaft und Energie (BMWi) via DLR under grants 50EE1711A to E and by the Helmholtz Society via the research program ATMO. The Park Falls and Lamont TCCON sites are supported by and would like to acknowledge NASA's Carbon Cycle Science Program (grant no. NNX17AE15G) and OCO-2 and OCO-3 projects (primary grant no. NNN12AA01C), respectively. The Burgos and Rikubetsu TCCON sites are supported in part by the GOSAT series project. Burgos is supported in part by the Energy Development Corp., the Philippines. Funding for the Edwards TCCON station is provided by NASA's Earth Science Division. Nicholas M. Deutscher is funded by ARC Future Fellowship FT180100327. Darwin and Wollongong TCCON stations are supported by ARC grants DP160100598, LE0668470, DP140101552, DP110103118, and DP0879468 and Darwin through NASA grants NAG5-12247 and NNG05-GD07G. The Lauder TCCON programme is core-funded by NIWA through New Zealand's Ministry of Business, Innovation and Employment.\n\nThe Trainou AirCore measurements have been supported by CEA, CNES, UVSQ, IPSL, and the EU H2020 RINGO project (GA no. 730944) and are part of the French consortium for Aircore measurements (LMD, LSCE, GSMA, CNES). The Sodankyl\u00e4 TCCON and AirCore measurements have been supported via the ESA FRM4GHG project (under grant agreement no. ESA-IPLPOE-LG-cl-LE-2015-1129) and the EU H2020 RINGO project.\n\nThe CH4 observations at Jungfraujoch were established as part of the Swiss National Air Pollution Monitoring Network and are supported through ICOS-CH, which is funded by the Swiss National Science Foundation and in-house contributions.\n\nWe would like to thank our colleague Thomas von Clarmann for his strong support in revising the equations in the Appendix of this paper.\n\nWe thank Michela Giusti in the Data Support team at ECMWF for retrieving and providing comments about the CAMS data.\n\nWe acknowledge the support by the Deutsche Forschungsgemeinschaft and the Open Access Publishing Fund of the Karlsruhe Institute of Technology. \n\nThis research has been supported by the Deutsche Forschungsgemeinschaft (project MOTIV (grant no. 290612604), and project TEDDY (grant no. 416767181)), the Ministerio de Econom\u00eda y Competitividad (grant no. CGL2016-80688-P), the European Space Agency (grant nos. 4000127561/19/I-NS and ESA-IPLPOE-LG-cl-LE-2015-1129), the Ministerium f\u00fcr Wissenschaft, Forschung und Kunst Baden-W\u00fcrttemberg, and the Bundesministerium f\u00fcr Bildung und Forschung for funding in the context of the ForHLR and HoreKa supercomputing infrastructure. \n\nThe article processing charges for this open-access publication were covered by the Karlsruhe Institute of Technology (KIT). \n\nAuthor contributions. MSc developed the idea for the optimal a posteriori combination of the level 2 remote-sensing products, and he prepared the figures and the manuscript. BE developed and performed the continuous MUSICA IASI data processing, where he was supported by MSc, CJD, FK, ANR, OEG, and ES. FH developed the PROFFIT-nadir retrieval code used for the MUSICA IASI processing. QT supported the use of the CAMS high-resolution data. TB, JL, AL, and AB are responsible for the TROPOMI processing and for making TROPOMI data available. HC and RK are responsible for the AirCore profile measurements over Sodankyl\u00e4. TL, MR, CC, and JP are responsible for the AirCore profile measurements over Trainou. MSt and FM are responsible for the GAW data of Jungfraujoch and Schauinsland, respectively. RK, DD, FH, KSt, DW, TW, CR, POW, IM, LTI, KSh, NMD, DWTG, VAV, and DFP are responsible for the TCCON data. All authors supported the generation of the final version of this paper. \n\nData availability. The MUSICA IASI data are described in (Schneider et al., 2022) and can be accessed at https://doi.org/10.35097/408 (Schneider et al., 2021a) and https://doi.org/10.35097/412 (Schneider et al., 2021b). The TROPOMI XCH4 data used in this study are described in Lorente et al. (2021a) and can be accessed at https://doi.org/10.5281/zenodo.4447228 (Lorente et al., 2021b). The TCCON data are available via the TCCON data archive, hosted by CaltechDATA (Total Carbon Column Observing Network Team, 2014, https://doi.org/10.14291/TCCON.GGG2014). For Trainou AirCore data, please contact Michel Ramonet (michel.ramonet@lsce.ipsl.fr), and for Sodankyl\u00e4 AirCore data, please contact Huilin Chen (huilin.chen@rug.nl). The Jungfraujoch GAW surface in situ CH4 data are available via the World Data Centre for Greenhouse Gases (WDCGG) and can be directly accessed at https://doi.org/10.50849/WDCGG_0023-6036-1002-01-01-9999 (Steinbacher, 2022). The Schainsland GAW surface in situ CH4 data up to 31 December 2018 are available via the WDCGG at https://gaw.kishou.go.jp/search/station#SSL (Meinhardt, 2019). For the Schauinsland CH4 data for 2019 and 2020, please contact Frank Meinhardt (frank.meinhardt@uba.de). The fused \"MUSICA IASI/RemoTeC TROPOMI\" example data presented in Fig. 15 are accessible at https://doi.org/10.35097/689 (Schneider and Ertl, 2022a). As already stated in Sect. 2.1, in this work we use the TROPOMI XCH4 data generated by the operational processing algorithm version 2.2.0 as input for the data fusion. For the example months of Fig. 15, we make additional data fusion calculations using the TROPOMI CH4 operational processing algorithm version 2.3.1, which among others offers additional coverage over ocean using glint mode observations. These fused \"MUSICA IASI/RemoTeC TROPOMI\" data are accessible at https://doi.org/10.35097/690 (Schneider and Ertl, 2022b). \n\nThe contact author has declared that neither they nor their co-authors have any competing interests.\n\nPublished - amt-15-4339-2022.pdf
", "abstract": "The thermal infrared nadir spectra of IASI (Infrared Atmospheric Sounding Interferometer) are successfully used for retrievals of different atmospheric trace gas profiles. However, these retrievals offer generally reduced information about the lowermost tropospheric layer due to the lack of thermal contrast close to the surface. Spectra of scattered solar radiation observed in the near-infrared and/or shortwave infrared, for instance by TROPOMI (TROPOspheric Monitoring Instrument), offer higher sensitivity near the ground and are used for the retrieval of total-column-averaged mixing ratios of a variety of atmospheric trace gases. Here we present a method for the synergetic use of IASI profile and TROPOMI total-column level 2 retrieval products. Our method uses the output of the individual retrievals and consists of linear algebra a posteriori calculations (i.e. calculation after the individual retrievals). We show that this approach has strong theoretical similarities to applying the spectra of the different sensors together in a single retrieval procedure but with the substantial advantage of being applicable to data generated with different individual retrieval processors, of being very time efficient, and of directly benefiting from the high quality and most recent improvements of the individual retrieval processors. We demonstrate the method exemplarily for atmospheric methane (CH\u2084). We perform a theoretical evaluation and show that the a posteriori combination method yields a total-column-averaged CH\u2084 product (XCH\u2084) that conserves the good sensitivity of the corresponding TROPOMI product while merging it with the high-quality upper troposphere\u2013lower stratosphere (UTLS) CH\u2084 partial-column information of the corresponding IASI product. As a consequence, the combined product offers additional sensitivity for the tropospheric CH\u2084 partial column, which is not provided by the individual TROPOMI nor the individual IASI product. The theoretically predicted synergetic effect is verified by comparisons to CH\u2084 reference data obtained from collocated XCH\u2084 measurements at 14 globally distributed TCCON (Total Carbon Column Observing Network) stations, CH\u2084 profile measurements made by 36 individual AirCore soundings, and tropospheric CH\u2084 data derived from continuous ground-based in situ observations made at two nearby Global Atmospheric Watch (GAW) mountain stations. The comparisons clearly demonstrate that the combined product can reliably detect the actual variations of atmospheric XCH\u2084, CH\u2084 in the UTLS, and CH\u2084 in the troposphere. A similar good reliability for the latter is not achievable by the individual TROPOMI and IASI products.", "date": "2022-07-29", "date_type": "published", "publication": "Atmospheric Measurement Techniques", "volume": "15", "number": "14", "publisher": "European Geosciences Union", "pagerange": "4339-4371", "id_number": "CaltechAUTHORS:20220811-234957000", "issn": "1867-8548", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220811-234957000", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Deutsche Forschungsgemeinschaft (DFG)", "grant_number": "290612604" }, { "agency": "Deutsche Forschungsgemeinschaft (DFG)", "grant_number": "416767181" }, { "agency": "Ministerio de Econom\u00eda y Competitividad (MINECO)", "grant_number": "CGL2016-80688-P" }, { "agency": "European Space Agency (ESA)", "grant_number": "4000127561/19/I-NS" }, { "agency": "European Space Agency (ESA)", "grant_number": "ESA-IPLPOE-LG-cl-LE-2015-1129" }, { "agency": "Karlsruhe Institute of Technology" }, { "agency": "Natural Sciences and Engineering Research Council of Canada (NSERC)" }, { "agency": "Environment and Climate Change Canada" }, { "agency": "Canadian Space Agency (CSA)" }, { "agency": "Canada Foundation for Innovation" }, { "agency": "Ontario Research Fund" }, { "agency": "Bundesministerium f\u00fcr Wirtschaft und Energie (BMWi)" }, { "agency": "Deutsches Zentrum f\u00fcr Luft- und Raumfahrt (DLR)", "grant_number": "50EE1711A-E" }, { "agency": "Helmholtz-Gemeinschaft Deutscher Forschungszentren (HGF)" }, { "agency": "NASA", "grant_number": "NNX17AE15G" }, { "agency": "NASA", "grant_number": "NNN12AA01C" }, { "agency": "Energy Development Corp." }, { "agency": "Australian Research Council", "grant_number": "FT180100327" }, { "agency": "Australian Research Council", "grant_number": "DP160100598" }, { "agency": "Australian Research Council", "grant_number": "LE0668470" }, { "agency": "Australian Research Council", "grant_number": "DP140101552" }, { "agency": "Australian Research Council", "grant_number": "DP110103118" }, { "agency": "Australian Research Council", "grant_number": "DP0879468" }, { "agency": "NASA", "grant_number": "NAG5-12247" }, { "agency": "NASA", "grant_number": "NNG05-GD07G" }, { "agency": "Ministry of Business, Innovation and Employment (New Zealand)" }, { "agency": "Commissariat a l'Energie Atomique (CEA)" }, { "agency": "Centre National d'\u00c9tudes Spatiales (CNES)" }, { "agency": "University of Versailles Saint-Quentin-en-Yvelines" }, { "agency": "Institute Pierre Simon Laplace" }, { "agency": "European Research Council (ERC)", "grant_number": "730944" }, { "agency": "Laboratoire des Sciences du Climat et de l'Environnement" }, { "agency": "Ministerium f\u00fcr Wissenschaft, Forschung und Kunst Baden-W\u00fcrttemberg" }, { "agency": "Bundesministerium f\u00fcr Bildung und Forschung (BMBF)" }, { "agency": "Swiss National Science Foundation (SNSF)" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/amt-15-4339-2022", "primary_object": { "basename": "amt-15-4339-2022.pdf", "url": "https://authors.library.caltech.edu/records/6ea3z-eb661/files/amt-15-4339-2022.pdf" }, "resource_type": "article", "pub_year": "2022", "author_list": "Schneider, Matthias; Ertl, Benjamin; et el." }, { "id": "https://authors.library.caltech.edu/records/ejckz-5d840", "eprint_id": 115474, "eprint_status": "archive", "datestamp": "2023-08-22 16:47:12", "lastmod": "2023-12-22 23:42:39", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Tribby-Ariana-L", "name": { "family": "Tribby", "given": "Ariana L." }, "orcid": "0000-0002-6435-4575" }, { "id": "Bois-J-S", "name": { "family": "Bois", "given": "Justin S." }, "orcid": "0000-0001-7137-8746" }, { "id": "Montzka-Stephen-A", "name": { "family": "Montzka", "given": "Stephen A." }, "orcid": "0000-0002-9396-0400" }, { "id": "Atlas-Elliot-L", "name": { "family": "Atlas", "given": "Elliot L." }, "orcid": "0000-0003-3847-5346" }, { "id": "Vimont-Isaac", "name": { "family": "Vimont", "given": "Isaac" }, "orcid": "0000-0002-0740-4927" }, { "id": "Lan-Xin", "name": { "family": "Lan", "given": "Xin" } }, { "id": "Tans-Pieter-P", "name": { "family": "Tans", "given": "Pieter P." }, "orcid": "0000-0002-9883-0787" }, { "id": "Elkins-James-W", "name": { "family": "Elkins", "given": "James W." }, "orcid": "0000-0003-4701-3100" }, { "id": "Blake-Donald-R", "name": { "family": "Blake", "given": "Donald R." }, "orcid": "0000-0002-8283-5014" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "Hydrocarbon Tracers Suggest Methane Emissions from Fossil Sources Occur Predominately Before Gas Processing and That Petroleum Plays Are a Significant Source", "ispublished": "pub", "full_text_status": "public", "keywords": "ethane; propane; natural gas; methane; energy; Environmental Chemistry; General Chemistry", "note": "\u00a9 2022 The Authors. Published by American Chemical Society. Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0).\n\nReceived 11 February 2022. Accepted 18 May 2022. Revised 18 May 2022. Published online 14 June 2022. Published in issue 5 July 2022. \n\nThis work was supported by the Resnick Sustainability Institute, including computations conducted in the Resnick High Performance Computing Center. A.L.T. received funding from NSF Award No. DGE-1745301. NOAA support was provided for HIPPO by NSF Award No. AGS-0628452; California Institute of Technology support for ATom was provided by NASA Grant Award No. NNX15AG61A. NOAA support for ATom was provided by NASA EVS2 Award No. NNH17AE26I; additional support was provided by NASA Upper Atmosphere Research Program award No. NNH13AV69I. NOAA laboratory and salary support is from NOAA Climate Change Program. S.A.M. acknowledges funding in part from NOAA Climate Program Office's AC4 Program. NOAA flask sampling and technical support was provided by Dr. Fred Moore of NOAA/CIRES. Additional technical support was provided by C. Siso, B. Miller, M. Crotwell, C. Sweeney, A. Andrews, J. Higgs, D. Neff, J. Kofler, K. McKain, M. Madronich, P. Handley, and S. Wolter. We thank IHS Markit for providing PointLogic economic data. \n\nThe authors declare no competing financial interest.\n\nPublished - acs.est.2c00927.pdf
Supplemental Material - es2c00927_si_001.pdf
", "abstract": "We use global airborne observations of propane (C\u2083H\u2088) and ethane (C\u2082H\u2086) from the Atmospheric Tomography (ATom) and HIAPER Pole-to-Pole Observations (HIPPO), as well as U.S.-based aircraft and tower observations by NOAA and from the NCAR FRAPPE campaign as tracers for emissions from oil and gas operations. To simulate global mole fraction fields for these gases, we update the default emissions' configuration of C\u2083H\u2088 used by the global chemical transport model, GEOS-Chem v13.0.0, using a scaled C\u2082H\u2086 spatial proxy. With the updated emissions, simulations of both C\u2083H\u2088 and C\u2082H\u2086 using GEOS-Chem are in reasonable agreement with ATom and HIPPO observations, though the updated emission fields underestimate C\u2083H\u2088 accumulation in the arctic wintertime, pointing to additional sources of this gas in the high latitudes (e.g., Europe). Using a Bayesian hierarchical model, we estimate global emissions of C\u2082H\u2086 and C\u2083H\u2088 from fossil fuel production in 2016\u20132018 to be 13.3 \u00b1 0.7 (95% CI) and 14.7 \u00b1 0.8 (95% CI) Tg/year, respectively. We calculate bottom-up hydrocarbon emission ratios using basin composition measurements weighted by gas production and find their magnitude is higher than expected and is similar to ratios informed by our revised alkane emissions. This suggests that emissions are dominated by pre-processing activities in oil-producing basins.", "date": "2022-07-05", "date_type": "published", "publication": "Environmental Science and Technology", "volume": "56", "number": "13", "publisher": "American Chemical Society", "pagerange": "9623-9631", "id_number": "CaltechAUTHORS:20220711-653341000", "issn": "0013-936X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220711-653341000", "funders": { "items": [ { "agency": "Resnick Sustainability Institute" }, { "agency": "NSF Graduate Research Fellowship", "grant_number": "DGE-1745301" }, { "agency": "NSF", "grant_number": "AGS-0628452" }, { "agency": "NASA", "grant_number": "NNX15AG61A" }, { "agency": "NASA", "grant_number": "NNH17AE261" }, { "agency": "NASA", "grant_number": "NNH13AV69I" }, { "agency": "National Oceanic and Atmospheric Administration (NOAA)" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "Division-of-Geological-and-Planetary-Sciences" }, { "id": "Division-of-Biology-and-Biological-Engineering" } ] }, "doi": "10.1021/acs.est.2c00927", "pmcid": "PMC9260955", "primary_object": { "basename": "acs.est.2c00927.pdf", "url": "https://authors.library.caltech.edu/records/ejckz-5d840/files/acs.est.2c00927.pdf" }, "related_objects": [ { "basename": "es2c00927_si_001.pdf", "url": "https://authors.library.caltech.edu/records/ejckz-5d840/files/es2c00927_si_001.pdf" } ], "resource_type": "article", "pub_year": "2022", "author_list": "Tribby, Ariana L.; Bois, Justin S.; et el." }, { "id": "https://authors.library.caltech.edu/records/hq900-2z083", "eprint_id": 114957, "eprint_status": "archive", "datestamp": "2023-08-22 15:44:34", "lastmod": "2023-10-23 20:00:04", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Berndt-Torsten", "name": { "family": "Berndt", "given": "Torsten" }, "orcid": "0000-0003-2014-6018" }, { "id": "Chen-Jing", "name": { "family": "Chen", "given": "Jing" }, "orcid": "0000-0001-6545-6197" }, { "id": "Kj\u00e6rgaard-Eva-R", "name": { "family": "Kj\u00e6rgaard", "given": "Eva R." }, "orcid": "0000-0001-8838-0084" }, { "id": "M\u00f8ller-Kristian-H", "name": { "family": "M\u00f8ller", "given": "Kristian H." }, "orcid": "0000-0001-8070-8516" }, { "id": "Tilgner-Andreas", "name": { "family": "Tilgner", "given": "Andreas" }, "orcid": "0000-0003-4021-4874" }, { "id": "Hoffmann-Erik-H", "name": { "family": "Hoffmann", "given": "Erik H." }, "orcid": "0000-0003-4560-0125" }, { "id": "Herrmann-Hartmut", "name": { "family": "Herrmann", "given": "Hartmut" }, "orcid": "0000-0001-7044-2101" }, { "id": "Crounse-John-D", "name": { "family": "Crounse", "given": "John D." }, "orcid": "0000-0001-5443-729X" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Kjaergaard-Henrik-G", "name": { "family": "Kjaergaard", "given": "Henrik G." }, "orcid": "0000-0002-7275-8297" } ] }, "title": "Hydrotrioxide (ROOOH) formation in the atmosphere", "ispublished": "pub", "full_text_status": "public", "keywords": "Multidisciplinary", "note": "\u00a9 2022 the authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original US government works. https://www.science.org/about/science-licenses-journal-article-reuse. \n\nSubmitted 8 December 2021; accepted 20 April 2022. \n\nThe authors thank A. Rohmer and K. Pielok for technical assistance and the tofTools team for providing the data analysis tools. This work used resources of the Deutsches Klimarechenzentrum (DKRZ) granted by its Scientific Steering Committee (WLA) under project ID bb1128. \n\nH.G.K. acknowledges funding from the Independent Research Fund Denmark (9040-00142B) and the High Performance Computing Center at the University of Copenhagen. E.H.H. and H.H. acknowledge funding from the German Research Foundation (project ORIGAMY, no. 447349939). P.O.W. and J.D.C. received financial support from the US National Science Fund (CHE-1905340). P.O.W. and H.G.K. received funding from the Alfred P. Sloan Foundation under award no. G-2019-12281. \n\nAuthor contributions: Conceptualization: T.B. and H.G.K. Methodology: All authors. Experiments: T.B. and J.D.C. Calculations: J.C., E.R.K., K.H.M., and H.G.K. Global modeling: A.T., E.H.H., H.H., and P.O.W. Writing \u2013 original draft: T.B. and H.G.K. Writing \u2013 review and editing: All authors. \n\nThe authors declare that they have no competing interests. \n\nData and materials availability: All theoretical calculation output files are available online through the public research data archive of the University of Copenhagen (25). All ECHAM-HAMMOZ model output files are available online through the public research data archive Zenodo (26). All other data are available in the main text or the supplementary materials.\n\nSupplemental Material - science.abn6012_sm.pdf
", "abstract": "Organic hydrotrioxides (ROOOH) are known to be strong oxidants used in organic synthesis. Previously, it has been speculated that they are formed in the atmosphere through the gas-phase reaction of organic peroxy radicals (RO\u2082) with hydroxyl radicals (OH). Here, we report direct observation of ROOOH formation from several atmospherically relevant RO\u2082 radicals. Kinetic analysis confirmed rapid RO\u2082 + OH reactions forming ROOOH, with rate coefficients close to the collision limit. For the OH-initiated degradation of isoprene, global modeling predicts molar hydrotrioxide formation yields of up to 1%, which represents an annual ROOOH formation of about 10 million metric tons. The atmospheric lifetime of ROOOH is estimated to be minutes to hours. Hydrotrioxides represent a previously omitted substance class in the atmosphere, the impact of which needs to be examined.", "date": "2022-05-26", "date_type": "published", "publication": "Science", "volume": "376", "number": "6596", "publisher": "American Association for the Advancement of Science", "pagerange": "979-982", "id_number": "CaltechAUTHORS:20220531-369780600", "issn": "0036-8075", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220531-369780600", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Independent Research Fund Denmark", "grant_number": "9040-00142B" }, { "agency": "University of Copenhagen" }, { "agency": "Deutsche Forschungsgemeinschaft (DFG)", "grant_number": "447349939" }, { "agency": "NSF", "grant_number": "CHE-1905340" }, { "agency": "Alfred P. Sloan Foundation", "grant_number": "G-2019-12281" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1126/science.abn6012", "primary_object": { "basename": "science.abn6012_sm.pdf", "url": "https://authors.library.caltech.edu/records/hq900-2z083/files/science.abn6012_sm.pdf" }, "resource_type": "article", "pub_year": "2022", "author_list": "Berndt, Torsten; Chen, Jing; et el." }, { "id": "https://authors.library.caltech.edu/records/7sr51-3n116", "eprint_id": 114331, "eprint_status": "archive", "datestamp": "2023-08-22 15:00:58", "lastmod": "2023-10-23 20:02:38", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Wolfe-Glenn-M", "name": { "family": "Wolfe", "given": "Glenn M." }, "orcid": "0000-0001-6586-4043" }, { "id": "Hanisco-Thomas-F", "name": { "family": "Hanisco", "given": "Thomas F." }, "orcid": "0000-0001-9434-8507" }, { "id": "Arkinson-Heather-R", "name": { "family": "Arkinson", "given": "Heather L." }, "orcid": "0000-0002-0282-4164" }, { "id": "Blake-Donald-R", "name": { "family": "Blake", "given": "Donald R." }, "orcid": "0000-0002-8283-5014" }, { "id": "Wisthaler-Armin", "name": { "family": "Wisthaler", "given": "Armin" }, "orcid": "0000-0001-5050-3018" }, { "id": "Mikoviny-Tomas", "name": { "family": "Mikoviny", "given": "Tomas" }, "orcid": "0000-0002-8461-0783" }, { "id": "Ryerson-Thomas-B", "name": { "family": "Ryerson", "given": "Thomas B." }, "orcid": "0000-0003-2800-7581" }, { "id": "Pollack-Ilana-B", "name": { "family": "Pollack", "given": "Ilana" }, "orcid": "0000-0001-7151-9756" }, { "id": "Peischl-Jeff", "name": { "family": "Peischl", "given": "Jeff" }, "orcid": "0000-0002-9320-7101" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Crounse-John-D", "name": { "family": "Crounse", "given": "John D." }, "orcid": "0000-0001-5443-729X" }, { "id": "St-Clair-Jason-M", "name": { "family": "St. Clair", "given": "Jason M." }, "orcid": "0000-0002-9367-5749" }, { "id": "Teng-Alexander-P", "name": { "family": "Teng", "given": "Alex" }, "orcid": "0000-0002-6434-0501" }, { "id": "Huey-L-Gregory", "name": { "family": "Huey", "given": "L. Gregory" }, "orcid": "0000-0002-0518-7690" }, { "id": "Liu-Xiaoxi", "name": { "family": "Liu", "given": "Xiaoxi" }, "orcid": "0000-0002-5104-8886" }, { "id": "Fried-Alan-E", "name": { "family": "Fried", "given": "Alan" }, "orcid": "0000-0002-5230-3527" }, { "id": "Weibring-Petter", "name": { "family": "Weibring", "given": "Petter" }, "orcid": "0000-0001-9567-3803" }, { "id": "Richter-Dirk", "name": { "family": "Richter", "given": "Dirk" }, "orcid": "0000-0002-2156-031X" }, { "id": "Walega-James", "name": { "family": "Walega", "given": "James" }, "orcid": "0000-0001-9167-8121" }, { "id": "Hall-Samuel-R", "name": { "family": "Hall", "given": "Samuel R." }, "orcid": "0000-0002-2060-7112" }, { "id": "Ullmann-Kirk", "name": { "family": "Ullmann", "given": "Kirk" }, "orcid": "0000-0002-4724-9634" }, { "id": "Jimenez-Jose-L", "name": { "family": "Jimenez", "given": "Jose L." }, "orcid": "0000-0001-6203-1847" }, { "id": "Campuzano-Jost-Pedro", "name": { "family": "Campuzano-Jost", "given": "Pedro" }, "orcid": "0000-0003-3930-010X" }, { "id": "Bui-T-Paul", "name": { "family": "Bui", "given": "T. Paul" }, "orcid": "0000-0001-9189-0405" }, { "id": "Diskin-Glenn-S", "name": { "family": "Diskin", "given": "Glenn" }, "orcid": "0000-0002-3617-0269" }, { "id": "Podolske-James-R", "name": { "family": "Podolske", "given": "James R." }, "orcid": "0000-0003-2771-5375" }, { "id": "Sachse-Glen-W", "name": { "family": "Sachse", "given": "Glen" } }, { "id": "Cohen-Ronald-C", "name": { "family": "Cohen", "given": "Ronald C." }, "orcid": "0000-0001-6617-7691" } ] }, "title": "Photochemical evolution of the 2013 California Rim Fire: synergistic impacts of reactive hydrocarbons and enhanced oxidants", "ispublished": "pub", "full_text_status": "public", "keywords": "Atmospheric Science", "note": "\u00a9 Author(s) 2022. This work is distributed under the Creative Commons Attribution 4.0 License. \n\nReceived: 04 Nov 2021 \u2013 Discussion started: 12 Nov 2021 \u2013 Revised: 22 Jan 2022 \u2013 Accepted: 15 Feb 2022 \u2013 Published: 01 Apr 2022. \n\nThe SEAC\u2074RS mission was supported by the NASA Tropospheric Composition program and grants from the NASA ROSES SEAC\u2074RS program (grant nos. NNH10ZDA001N, NNX12AC03G, and NNX12AB82G). We thank the DC-8 pilots, crew, payload operators, and mission scientists, for their hard work and dedication. We thank Luke Ziemba, Lee Thornhill, and the LARGE team, for the LAS data. We thank Anthony Bucholtz, for the BBR data. We are also grateful to NASA ESPO, for the mission logistics. Analysis and modeling were supported by NOAA Climate Program Office's Atmospheric Chemistry, Carbon Cycle, and Climate program (grant no. NA17OAR4310004). The Jimenez group acknowledges support from NASA (grant nos. 80NSSC19k0124 and 80NSSC18K0630). The PTR-MS measurements during SEAC\u2074RS were supported by the Austrian Federal Ministry for Transport, Innovation, and Technology (bmvit) through the Austrian Space Applications Programme (ASAP) of the Austrian Research Promotion Agency (FFG). Armin Wisthaler and Tomas Mikoviny received support from the Visiting Scientist Program at the National Institute of Aerospace (NIA). We thank many colleagues for their assistance, insight, and feedback, including Steve Brown, Christine Wiedinmyer, Sarah Strode, Ann Marie Carlton, Matt Coggon, Jim Roberts, Joel Thornton, and Qiaoyun Peng. \n\nThis research has been supported by the NASA Earth Sciences Division (grant nos. NNH10ZDA001N, NNX12AC03G, NNX12AB82G, 80NSSC19K0124, and 80NSSC18K0630) and the NASA Climate Program Office (grant no. NA17OAR4310004). \n\nAuthor contributions. GMW conceptualized the study, conducted the modeling and analysis, and wrote the paper. All authors contributed to the collection of SEAC\u2074RS observations used to constrain and evaluate the model. \n\nThe supplement related to this article is available online at: https://doi.org/10.5194/acp-22-4253-2022-supplement. \n\nCode and data availability. Data used in this study are archived at https://doi.org/10.5067/Aircraft/SEAC4RS/Aerosol-TraceGas-Cloud (SEAC4RS Science Team, 2013). The F0AM box model is available at https://github.com/AirChem/F0AM (last access: 18 May 2021) and https://doi.org/10.5281/zenodo.5752566 (Wolfe, 2021). The model setup code is available from the contact author upon request. \n\nThis paper was edited by Andreas Hofzumahaus and reviewed by D. A. J. Jaffe and one anonymous referee. \n\nCompeting interests. At least one of the (co-)authors is a member of the editorial board of Atmospheric Chemistry and Physics. The peer-review process was guided by an independent editor, and the authors also have no other competing interests to declare.\n\nPublished - acp-22-4253-2022.pdf
Supplemental Material - acp-22-4253-2022-supplement.pdf
", "abstract": "Large wildfires influence regional atmospheric composition, but chemical complexity challenges model predictions of downwind impacts. Here, we elucidate key connections within gas-phase photochemistry and assess novel chemical processes via a case study of the 2013 California Rim Fire plume. Airborne in situ observations, acquired during the NASA Studies of Emissions, Atmospheric Composition, Clouds and Climate Coupling by Regional Surveys (SEAC\u2074RS) mission, illustrate the evolution of volatile organic compounds (VOCs), oxidants, and reactive nitrogen over 12\u2009h of atmospheric aging. Measurements show rapid formation of ozone and peroxyacyl nitrates (PNs), sustained peroxide production, and prolonged enhancements in oxygenated VOCs and nitrogen oxides (NO\u2093). \n\nObservations and Lagrangian trajectories constrain a 0-D puff model that approximates plume photochemical history and provides a framework for evaluating process interactions. Simulations examine the effects of (1) previously unmeasured reactive VOCs identified in recent laboratory studies and (2) emissions and secondary production of nitrous acid (HONO). Inclusion of estimated unmeasured VOCs leads to a 250\u2009% increase in OH reactivity and a 70\u2009% increase in radical production via oxygenated VOC photolysis. HONO amplifies radical cycling and serves as a downwind NO\u2093 source, although impacts depend on how HONO is introduced. The addition of initial HONO (representing primary emissions) or particulate nitrate photolysis amplifies ozone production, while heterogeneous conversion of NO\u2082 suppresses ozone formation. Analysis of radical initiation rates suggests that oxygenated VOC photolysis is a major radical source, exceeding HONO photolysis when averaged over the first 2\u2009h of aging. Ozone production chemistry transitions from VOC sensitive to NO\u2093 sensitive within the first hour of plume aging, with both peroxide and organic nitrate formation contributing significantly to radical termination. To simulate smoke plume chemistry accurately, models should simultaneously account for the full reactive VOC pool and all relevant oxidant sources.", "date": "2022-04-01", "date_type": "published", "publication": "Atmospheric Chemistry and Physics", "volume": "22", "number": "6", "publisher": "European Geosciences Union", "pagerange": "4253-4275", "id_number": "CaltechAUTHORS:20220414-28035000", "issn": "1680-7324", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220414-28035000", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NNH10ZDA001N" }, { "agency": "NASA", "grant_number": "NNX12AC03G" }, { "agency": "NASA", "grant_number": "NNX12AB82G" }, { "agency": "National Oceanic and Atmospheric Administration (NOAA)", "grant_number": "NA17OAR4310004" }, { "agency": "NASA", "grant_number": "80NSSC19K0124" }, { "agency": "NASA", "grant_number": "80NSSC18K0630" }, { "agency": "Bundesministerium f\u00fcr Verkehr, Innovation und Technologie (BMVIT)" }, { "agency": "\u00d6sterreichische Forschungsf\u00f6rderungsgesellschaft (FFG)" }, { "agency": "National Institute of Aerospace (NIA)" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/acp-22-4253-2022", "primary_object": { "basename": "acp-22-4253-2022-supplement.pdf", "url": "https://authors.library.caltech.edu/records/7sr51-3n116/files/acp-22-4253-2022-supplement.pdf" }, "related_objects": [ { "basename": "acp-22-4253-2022.pdf", "url": "https://authors.library.caltech.edu/records/7sr51-3n116/files/acp-22-4253-2022.pdf" } ], "resource_type": "article", "pub_year": "2022", "author_list": "Wolfe, Glenn M.; Hanisco, Thomas F.; et el." }, { "id": "https://authors.library.caltech.edu/records/k1439-rny35", "eprint_id": 114336, "eprint_status": "archive", "datestamp": "2023-10-09 21:01:00", "lastmod": "2023-10-24 16:30:27", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Allen-Hannah-M", "name": { "family": "Allen", "given": "Hannah M." }, "orcid": "0000-0002-4218-5133" }, { "id": "Crounse-John-D", "name": { "family": "Crounse", "given": "John D." }, "orcid": "0000-0001-5443-729X" }, { "id": "Kim-Michelle-J", "name": { "family": "Kim", "given": "Michelle J." }, "orcid": "0000-0002-4922-4334" }, { "id": "Teng-Alexander-P", "name": { "family": "Teng", "given": "Alexander P." }, "orcid": "0000-0002-6434-0501" }, { "id": "Ray-Eric-A", "name": { "family": "Ray", "given": "Eric A." }, "orcid": "0000-0001-8727-9849" }, { "id": "McKain-Kathryn", "name": { "family": "McKain", "given": "Kathryn" }, "orcid": "0000-0002-8323-5758" }, { "id": "Sweeney-Colm", "name": { "family": "Sweeney", "given": "Colm" }, "orcid": "0000-0001-9568-0050" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "H\u2082O\u2082 and CH\u2083OOH (MHP) in the Remote Atmosphere: 1. Global Distribution and Regional Influences", "ispublished": "pub", "full_text_status": "public", "keywords": "Space and Planetary Science; Earth and Planetary Sciences (miscellaneous); Atmospheric Science; Geophysics", "note": "\u00a9 2022. American Geophysical Union. \n\nIssue Online: 18 March 2022. Version of Record online: 18 March 2022. Accepted manuscript online: 02 March 2022. Manuscript accepted: 28 January 2022. Manuscript revised: 23 December 2021. Manuscript received: 13 August 2021. \n\nFunding for this work was provided by NASA Grant No. NNX15AG61A. Additional support for H. M. A. was provided by the National Science Foundation Graduate Research Fellowship under Grant No. DGE-1144469 and additional support for M. J. K. was provided by the National Science Foundation Grant No. 1524860. The authors would like to thank the organizers of the ATom Mission, particularly S. C. Wofsy and T. B. Ryerson, for providing the opportunity to gather these data. We would also like to thank E. Czech, D. Jordan, and the people at ESPO, as well as the pilots and crew of the DC-8 for the infrastructural support that made these measurements possible. \n\nData Availability Statement. The data presented in this paper are available at https://doi.org/10.3334/ORNLDAAC/1581.\n\nPublished - 2021JD035701.pdf
Supplemental Material - 2021jd035701-sup-0001-supporting_information_si-s01.pdf
", "abstract": "Atmospheric hydroperoxides are a significant component of the atmosphere's oxidizing capacity. Two of the most abundant hydroperoxides, hydrogen peroxide (H\u2082O\u2082) and methyl hydroperoxide (MHP, CH\u2083OOH), were measured in the remote atmosphere using chemical ionization mass spectrometry aboard the NASA DC-8 aircraft during the Atmospheric Tomography Mission. These measurements present a seasonal investigation into the global distribution of these two hydroperoxides, with near pole-to-pole coverage across the Pacific and Atlantic Ocean basins and from the marine boundary layer to the upper troposphere and lower stratosphere. H\u2082O\u2082 mixing ratios are highest between 2 and 4 km altitude in the equatorial region of the Atlantic Ocean basin, where they reach global maximums of 3.6\u20136.5 ppbv depending on season. MHP mixing ratios reach global maximums of 4.3\u20138.6 ppbv and are highest between 1 and 3 km altitude, but peak in different regions depending on season. A major factor contributing to the global H\u2082O\u2082 distribution is the influence of biomass burning emissions in the Atlantic Ocean basin, encountered in all four seasons, where the highest H\u2082O\u2082 mixing ratios were found to correlate strongly with increased mixing ratios of the biomass burning tracers hydrogen cyanide (HCN) and carbon monoxide (CO). This biomass burning enhanced H\u2082O\u2082 by a factor of 1.3\u20132.2, on average, in the Atlantic compared with the Pacific Ocean basin.", "date": "2022-03-27", "date_type": "published", "publication": "Journal of Geophysical Research. Atmospheres", "volume": "127", "number": "6", "publisher": "American Geophysical Union", "pagerange": "Art. No. e2021JD035701", "id_number": "CaltechAUTHORS:20220414-413126000", "issn": "2169-897X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220414-413126000", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NNX15AG61A" }, { "agency": "NSF Graduate Research Fellowship", "grant_number": "DGE-1144469" }, { "agency": "NSF Atmospheric and Geospace Sciences Fellowship", "grant_number": "AGS-1524860" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2021JD035701", "primary_object": { "basename": "2021JD035701.pdf", "url": "https://authors.library.caltech.edu/records/k1439-rny35/files/2021JD035701.pdf" }, "related_objects": [ { "basename": "2021jd035701-sup-0001-supporting_information_si-s01.pdf", "url": "https://authors.library.caltech.edu/records/k1439-rny35/files/2021jd035701-sup-0001-supporting_information_si-s01.pdf" } ], "resource_type": "article", "pub_year": "2022", "author_list": "Allen, Hannah M.; Crounse, John D.; et el." }, { "id": "https://authors.library.caltech.edu/records/f8jpe-bsm04", "eprint_id": 113914, "eprint_status": "archive", "datestamp": "2023-10-09 20:59:19", "lastmod": "2023-10-24 16:29:50", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Allen-Hannah-M", "name": { "family": "Allen", "given": "Hannah M." }, "orcid": "0000-0002-4218-5133" }, { "id": "Bates-Kelvin-H", "name": { "family": "Bates", "given": "Kelvin H." }, "orcid": "0000-0001-7544-9580" }, { "id": "Crounse-John-D", "name": { "family": "Crounse", "given": "John D." }, "orcid": "0000-0001-5443-729X" }, { "id": "Kim-Michelle-J", "name": { "family": "Kim", "given": "Michelle J." }, "orcid": "0000-0002-4922-4334" }, { "id": "Teng-Alexander-P", "name": { "family": "Teng", "given": "Alexander P." }, "orcid": "0000-0002-6434-0501" }, { "id": "Ray-Eric-A", "name": { "family": "Ray", "given": "Eric A." }, "orcid": "0000-0001-8727-9849" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "H\u2082O\u2082 and CH\u2083OOH (MHP) in the Remote Atmosphere: 2. Physical and Chemical Controls", "ispublished": "pub", "full_text_status": "public", "keywords": "Hydroperoxides; ATom Mission; Remote Atmosphere; Deposition; Convection; Photochemistry; Space and Planetary Science; Earth and Planetary Sciences (miscellaneous); Atmospheric Science; Geophysics", "note": "\u00a9 2022 American Geophysical Union. \n\nIssue Online: 18 March 2022; Version of Record online: 18 March 2022; Accepted manuscript online: 01 March 2022; Manuscript accepted: 27 February 2022; Manuscript revised: 11 February 2022; Manuscript received: 13 August 2021. \n\nFunding for this work was provided by NASA Grant No. NNX15AG61A. Additional support for H. M. Allen was provided by the National Science Foundation Graduate Research Fellowship under Grant No. DGE-1144469 and additional support for M. J. Kim was provided by the National Science Foundation Grant No. 1524860. The authors would like to thank the organizers of the ATom Mission, particularly S. C. Wofsy and T. B. Ryerson, for providing the opportunity to gather these data. We would also like to thank E. Czech, D. Jordan, and the people at ESPO, as well as the pilots and crew of the DC-8 for the infrastructural support that made these measurements possible. \n\nData Availability Statement: The field data collected during the ATom deployments and used in this paper are available at https://doi.org/10.3334/ORNLDAAC/1581.\n\nPublished - 2021JD035702.pdf
Accepted Version - 2021JD035702-acc.pdf
Supplemental Material - 2021jd035702-sup-0001-supporting_information_si-s01.pdf
", "abstract": "Hydrogen peroxide (H\u2082O\u2082) and methyl hydroperoxide (MHP, CH\u2083OOH) serve as HO\u2093 (OH and HO\u2082 radicals) reservoirs and therefore as useful tracers of HO\u2093 chemistry. Both hydroperoxides were measured during the 2016\u20132018 Atmospheric Tomography Mission as part of a global survey of the remote troposphere over the Pacific and Atlantic Ocean basins conducted using the NASA DC-8 aircraft. To assess the relative contributions of chemical and physical processes to the global hydroperoxide budget and their impact on atmospheric oxidation potential, we compare the observations with two models, a diurnal steady-state photochemical box model and the global chemical transport model Goddard Earth Observing System (GEOS)-Chem. We find that the models systematically under-predict H\u2082O\u2082 by 5%\u201320% and over-predict MHP by 40%\u201350% relative to measurements. In the marine boundary layer, over-predictions of H\u2082O\u2082 in a photochemical box model are used to estimate H\u2082O\u2082 boundary-layer mean deposition velocities of 1.0\u20131.32 cm s\u207b\u00b9, depending on season; this process contributes to up to 5%\u201310% of HO\u2093 loss in this region. In the upper troposphere and lower stratosphere, MHP is under-predicted and H\u2082O\u2082 is over-predicted by a factor of 2\u20133 on average. The differences between the observations and predictions are associated with recent convection: MHP is under-estimated and H\u2082O\u2082 is over-estimated in air parcels that have experienced recent convective influence.", "date": "2022-03-27", "date_type": "published", "publication": "Journal of Geophysical Research. Atmospheres", "volume": "127", "number": "6", "publisher": "American Geophysical Union", "pagerange": "Art. No. e2021JD035702", "id_number": "CaltechAUTHORS:20220315-625973000", "issn": "2169-897X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220315-625973000", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NNX15AG61A" }, { "agency": "NSF Graduate Research Fellowship", "grant_number": "DGE-1144469" }, { "agency": "NSF", "grant_number": "1524860" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2021jd035702", "primary_object": { "basename": "2021JD035702-acc.pdf", "url": "https://authors.library.caltech.edu/records/f8jpe-bsm04/files/2021JD035702-acc.pdf" }, "related_objects": [ { "basename": "2021JD035702.pdf", "url": "https://authors.library.caltech.edu/records/f8jpe-bsm04/files/2021JD035702.pdf" }, { "basename": "2021jd035702-sup-0001-supporting_information_si-s01.pdf", "url": "https://authors.library.caltech.edu/records/f8jpe-bsm04/files/2021jd035702-sup-0001-supporting_information_si-s01.pdf" } ], "resource_type": "article", "pub_year": "2022", "author_list": "Allen, Hannah M.; Bates, Kelvin H.; et el." }, { "id": "https://authors.library.caltech.edu/records/1zth9-s9n84", "eprint_id": 114744, "eprint_status": "archive", "datestamp": "2023-09-15 07:37:44", "lastmod": "2023-10-23 21:36:26", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Brune-William-H", "name": { "family": "Brune", "given": "William H." }, "orcid": "0000-0002-1609-4051" }, { "name": { "family": "Miller", "given": "David O." } }, { "name": { "family": "Thames", "given": "Alexander B." } }, { "name": { "family": "Brosius", "given": "Alexandra L." }, "orcid": "0000-0003-2393-3834" }, { "name": { "family": "Barletta", "given": "Barbara" }, "orcid": "0000-0003-3046-014X" }, { "name": { "family": "Blake", "given": "Donald R." }, "orcid": "0000-0002-8283-5014" }, { "name": { "family": "Blake", "given": "Nicola J." }, "orcid": "0000-0002-7900-1297" }, { "name": { "family": "Chen", "given": "Gao" } }, { "name": { "family": "Choi", "given": "Yonghoon" }, "orcid": "0000-0001-6529-4722" }, { "name": { "family": "Crawford", "given": "James H." }, "orcid": "0000-0002-6982-0934" }, { "name": { "family": "DiGangi", "given": "Joshua P." }, "orcid": "0000-0002-6764-8624" }, { "name": { "family": "Diskin", "given": "Glenn" }, "orcid": "0000-0002-3617-0269" }, { "name": { "family": "Fried", "given": "Alan" }, "orcid": "0000-0002-5230-3527" }, { "name": { "family": "Hall", "given": "Samuel R." }, "orcid": "0000-0002-2060-7112" }, { "name": { "family": "Hanisco", "given": "Thomas F." }, "orcid": "0000-0001-9434-8507" }, { "name": { "family": "Huey", "given": "Greg L." } }, { "name": { "family": "Hughes", "given": "Stacey C." } }, { "id": "Kim-Michelle-J", "name": { "family": "Kim", "given": "Michelle" }, "orcid": "0000-0002-4922-4334" }, { "name": { "family": "Meinardi", "given": "Simone" }, "orcid": "0000-0003-4828-9889" }, { "name": { "family": "Montzka", "given": "Denise D." } }, { "name": { "family": "Pusede", "given": "Sally E." } }, { "name": { "family": "Schroeder", "given": "Jason R." } }, { "id": "Teng-Alexander-P", "name": { "family": "Teng", "given": "Alex" }, "orcid": "0000-0002-6434-0501" }, { "name": { "family": "Tanner", "given": "David J." }, "orcid": "0000-0001-6445-8713" }, { "name": { "family": "Ullmann", "given": "Kirk" }, "orcid": "0000-0002-4724-9634" }, { "name": { "family": "Walega", "given": "James" }, "orcid": "0000-0001-9167-8121" }, { "name": { "family": "Weinheimer", "given": "Andrew" }, "orcid": "0000-0001-6175-8286" }, { "name": { "family": "Wisthaler", "given": "Armin" }, "orcid": "0000-0001-5050-3018" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "Observations of atmospheric oxidation and ozone production in South Korea", "ispublished": "pub", "full_text_status": "public", "keywords": "Air quality; Hydroxyl; Hydroperoxyl; Aerosol uptake of hydroperoxyl; Missing OH reactivity; Ozone production rate; Atmospheric Science; General Environmental Science", "note": "\u00a9 2021 The Authors. Published by Elsevier Under a Creative Commons license. Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0).\n\nReceived 9 July 2021, Revised 9 November 2021, Accepted 13 November 2021, Available online 20 November 2021, Version of Record 24 November 2021. \n\nWe thank our fellow KORUS_AQ scientists from the United States and Korea, Barry Lefer and the rest of NASA management involved in KORUS-AQ, and the NASA DC-8 pilots and operations crew. VOC measurements by PTR-MS were supported by the Austrian Federal Ministry for Transport, Innovation and Technology (bmvit) through the Austrian Space Applications Programme (ASAP) of the Austrian Research Promotion Agency (FFG). The PTR-MS instrument team (P. Eichler, L. Kaser, T. Mikoviny, M. M\u00fcller) is acknowledged for providing the PTR-MS data for this study. SRH and KU were supported by NASA grant NNX15AT99G. WHB, DOM, ABT, and ALB were supported by NASA grants NNX15AT82G and 80NSSC19K1590. \n\nData availability Data and LaRC model output are openly available from the NASA Langley Research Center archive: KORUS-AQ DOI: 10.5067/Suborbital/KORUSAQ/DATA01 (Aknan and Chen, 2017).\n\nCRediT authorship contribution statement. William H. Brune: Investigation, Methodology, Writing \u2013 original draft, review & editing, Software, Data curation, Formal analysis, Project administration, Supervision; David O. Miller: Investigation, Methodology, Writing - review & editing, Software, Data curation. Alexander B. Thames: Writing - review & editing, Investigation, Data curation. Alexandra L. Brosius: Investigation, Data Curation, Methodology, Software, Formal analysis. Donald R. Blake: Investigation, Data Curation. Nicola J. Blake: Investigation, Data Curation. Gao Chen: Investigation, Data Curation. James H. Crawford: Investigation, Methodology, Data Curation. Joshua P. Digangi: Investigation, Data Curation. Glenn Diskin: Investigation, Data Curation. Alan Fried: Investigation, Data Curation. Samuel R. Hall: Writing - review & editing, Investigation, Data Curation. Thomas F. Hanisco: Investigation, Data Curation. Greg L. Huey: Investigation, Data Curation. Stacey C. Hughes: Investigation, Data Curation. Michelle Kim: Investigation, Data Curation. Simone Meinardi: Investigation, Data Curation. Denise D. Montzka: Investigation, Data Curation. Sally E. Pusede: Investigation, Data Curation. Jason R. Schroeder: Investigation, Data Curation. David J. Tanner: Investigation, Data Curation. Alex Teng: Investigation, Data Curation. Kirk Ullmann: Investigation, Data Curation. James Walega: Investigation, Data Curation. Andrew Weinheimer: Investigation, Data Curation. Armin Wisthaler: Investigation, Data Curation. Paul O. Wennberg: Investigation, Data Curation. \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\nPublished - 1-s2.0-S1352231021006762-main.pdf
", "abstract": "South Korea routinely experiences poor air quality with ozone and small particles exceeding air quality standards. To build a better understanding of this problem, in 2016, the KORea-United States cooperative Air Quality (KORUS-AQ) study collected surface and airborne measurements of many chemical species, including the reactive gases hydroxyl (OH) and hydroperpoxyl (HO\u2082). Several different results are reported here. First, OH and HO\u2082 measured on the NASA DC-8 agree to within uncertainties with values calculated by two different box models, both in statistical comparisons and as a function of altitude from the surface to 8 km. These comparisons show substantial scatter, likely due to both variability in instrument performance and the difficulty in interpolating measurements made with frequencies different from those of the model time step. Second, OH and HO\u2082 calculated by a model including HO\u2082 uptake on aerosol particles in the chemical mechanism are inconsistent with observations. Third, in the planetary boundary layer over both ocean and land, measured and model-calculated OH reactivity are sometimes different, and this missing OH reactivity, which is as much as \u223c4 s\u207b\u00b9, increased from April to June and originated primarily from the Korean peninsula. Fourth, repeated missed approaches at the Seoul Air Base during several days show that the changes in the sum of ozone and nitrogen dioxide are consistent with ozone production rates calculated from HO2 either observed or modeled by the Langley Research Center model.", "date": "2022-01-15", "date_type": "published", "publication": "Atmospheric Environment", "volume": "269", "publisher": "Elsevier", "pagerange": "Art. No. 118854", "id_number": "CaltechAUTHORS:20220513-557938000", "issn": "1352-2310", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220513-557938000", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Bundesministerium f\u00fcr Verkehr, Innovation und Technologie (BMVIT)" }, { "agency": "Austrian Research Promotion Agency (FFG)" }, { "agency": "NASA", "grant_number": "NNX15AT99G" }, { "agency": "NASA", "grant_number": "NNX15AT82G" }, { "agency": "NASA", "grant_number": "80NSSC19K1590" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/j.atmosenv.2021.118854", "primary_object": { "basename": "1-s2.0-S1352231021006762-main.pdf", "url": "https://authors.library.caltech.edu/records/1zth9-s9n84/files/1-s2.0-S1352231021006762-main.pdf" }, "resource_type": "article", "pub_year": "2022", "author_list": "Brune, William H.; Miller, David O.; et el." }, { "id": "https://authors.library.caltech.edu/records/8dy6f-8ma09", "eprint_id": 111714, "eprint_status": "archive", "datestamp": "2023-08-22 12:49:38", "lastmod": "2023-10-23 20:42:13", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Park-Do-Hyeon", "name": { "family": "Park", "given": "Do-Hyeon" } }, { "id": "Cho-Chaeyoon", "name": { "family": "Cho", "given": "Chaeyoon" } }, { "id": "Kim-Hyeonmin", "name": { "family": "Kim", "given": "Hyeonmin" } }, { "id": "Park-Rokjin-J", "name": { "family": "Park", "given": "Rokjin J." } }, { "id": "Anderson-Bruce", "name": { "family": "Anderson", "given": "Bruce" } }, { "id": "Lee-Taehyoung", "name": { "family": "Lee", "given": "Taehyoung" } }, { "id": "Huey-Greg-L", "name": { "family": "Huey", "given": "Greg L." } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Weinheimer-Andrew-J", "name": { "family": "Weinheimer", "given": "Andrew J." }, "orcid": "0000-0001-6175-8286" }, { "id": "Yum-Seong-Soo", "name": { "family": "Yum", "given": "Seong Soo" } }, { "id": "Long-Russell", "name": { "family": "Long", "given": "Russell" } }, { "id": "Kim-Sang-Woo", "name": { "family": "Kim", "given": "Sang-Woo" } } ] }, "title": "Boundary layer versus free tropospheric submicron particle formation: A case study from NASA DC-8 observations in the Asian continental outflow during the KORUS-AQ campaign", "ispublished": "pub", "full_text_status": "restricted", "keywords": "Submicron particle formation; Secondary inorganic aerosols; Boundary layer; Free troposphere; KORUS-AQ", "note": "\u00a9 2021 Elsevier B.V. \n\nReceived 13 May 2021, Revised 14 September 2021, Accepted 14 September 2021, Available online 16 September 2021. \n\nThe authors are grateful to the NASA DC-8 pilots and crew, and to all members of the KORUS-AQ science team for their contributions during the field campaign and the agencies operating the surface networks. This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIT)(No. NRF-2021R1A4A5032320). \n\nDeclaration of Competing Interest: None.", "abstract": "In this study, we contrasted major secondary inorganic species and processes responsible for submicron particle formation (SPF) events in the boundary layer (BL) and free troposphere (FT) over the Korean Peninsula during Korea-United States Air Quality (KORUS-AQ) campaign (May\u2013June 2016) using aircraft observations. The number concentration of ultrafine particles with diameters between 3 nm and 10 nm (N_(CN3\u201310)) during the entire KORUS-AQ period reached a peak (7606 \u00b1 12,003 cm\u207b\u00b3) at below 1 km altitude, implying that the particle formation around the Korean Peninsula primarily occurred in the daytime BL. During the BL SPF case (7 May 2016), the SPF over Seoul metropolitan area was more attributable to oxidation of NO\u2082 rather than SO\u2082-to-sulfate conversion. From the analysis of the relationship between nitrogen oxidation ratio (NOR) and temperature or relative humidity (RH), NOR showed a positive correlation only with temperature. This suggests that homogeneous gas-phase reactions of NO\u2082 with OH or O\u2083 contributed to nitrate formation. From the relationship between N_(CN3\u201310) (> 10,000 cm\u207b\u00b3) and the NOR (or sulfur oxidation ratio) at Olympic Park in Seoul during the entire KORUS-AQ period, it was regarded that the relative importance of nitrogen oxidation was grown as the N_(CN3\u201310) increased. During the FT SPF case (31 May 2016) over the yellow sea, the SO\u2082-to-sulfate conversion seemed to influence SPF highly. The sulfate/CO ratio had a positive correlation with both the temperature and RH, suggesting that aqueous-phase pathways as well as gas-phase reactions might be attributable to sulfate formation in the FT. In particular, FT SPF event on 31 May was possibly caused by the direct transport of SO\u2082 precursors from the continent above the shallow marine boundary layer under favorable conditions for FT SPF events, such as decreased aerosol surface area and increased solar radiation.", "date": "2021-12-15", "date_type": "published", "publication": "Atmospheric Research", "volume": "264", "publisher": "Elsevier", "pagerange": "Art. No. 105857", "id_number": "CaltechAUTHORS:20211102-201741089", "issn": "0169-8095", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20211102-201741089", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "National Research Foundation of Korea", "grant_number": "NRF-2021R1A4A5032320" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/j.atmosres.2021.105857", "resource_type": "article", "pub_year": "2021", "author_list": "Park, Do-Hyeon; Cho, Chaeyoon; et el." }, { "id": "https://authors.library.caltech.edu/records/8hjh5-avx78", "eprint_id": 112321, "eprint_status": "archive", "datestamp": "2023-08-22 12:46:37", "lastmod": "2023-10-23 21:01:36", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Xu-Lu", "name": { "family": "Xu", "given": "Lu" }, "orcid": "0000-0002-0021-9876" }, { "id": "Crounse-J-D", "name": { "family": "Crounse", "given": "John D." }, "orcid": "0000-0001-5443-729X" }, { "id": "Vasquez-Krystal-T", "name": { "family": "Vasquez", "given": "Krystal T." }, "orcid": "0000-0003-4540-4212" }, { "id": "Allen-Hannah-M", "name": { "family": "Allen", "given": "Hannah" }, "orcid": "0000-0002-4218-5133" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" }, { "name": { "family": "Bourgeois", "given": "Ilann" }, "orcid": "0000-0002-2875-1258" }, { "name": { "family": "Brown", "given": "Steven S." }, "orcid": "0000-0001-7477-9078" }, { "name": { "family": "Campuzano-Jost", "given": "Pedro" }, "orcid": "0000-0003-3930-010X" }, { "name": { "family": "Coggon", "given": "Matthew M." }, "orcid": "0000-0002-5763-1925" }, { "name": { "family": "Crawford", "given": "James H." }, "orcid": "0000-0002-6982-0934" }, { "name": { "family": "DiGangi", "given": "Joshua P." }, "orcid": "0000-0002-6764-8624" }, { "name": { "family": "Diskin", "given": "Glenn S." }, "orcid": "0000-0002-3617-0269" }, { "name": { "family": "Fried", "given": "Alan" } }, { "name": { "family": "Gargulinski", "given": "Emily M." }, "orcid": "0000-0002-3949-6627" }, { "name": { "family": "Gilman", "given": "Jessica B." }, "orcid": "0000-0002-7899-9948" }, { "name": { "family": "Gkatzelis", "given": "Georgios I." }, "orcid": "0000-0002-4608-3695" }, { "name": { "family": "Guo", "given": "Hongyu" }, "orcid": "0000-0003-0487-3610" }, { "name": { "family": "Hair", "given": "Johnathan W." }, "orcid": "0000-0002-9672-1237" }, { "name": { "family": "Hall", "given": "Samuel R." }, "orcid": "0000-0002-2060-7112" }, { "name": { "family": "Halliday", "given": "Hannah A." }, "orcid": "0000-0001-9499-9836" }, { "name": { "family": "Hanisco", "given": "Thomas F." }, "orcid": "0000-0001-9434-8507" }, { "name": { "family": "Hannun", "given": "Reem A." }, "orcid": "0000-0001-5195-5307" }, { "name": { "family": "Holmes", "given": "Christopher D." }, "orcid": "0000-0002-2727-0954" }, { "name": { "family": "Huey", "given": "L. Gregory" }, "orcid": "0000-0002-0518-7690" }, { "name": { "family": "Jimenez", "given": "Jose L." }, "orcid": "0000-0001-6203-1847" }, { "name": { "family": "Lamplugh", "given": "Aaron" } }, { "name": { "family": "Lee", "given": "Young Ro" } }, { "name": { "family": "Liao", "given": "Jin" } }, { "name": { "family": "Lindaas", "given": "Jakob" }, "orcid": "0000-0003-1872-3162" }, { "name": { "family": "Neuman", "given": "J. Andrew" }, "orcid": "0000-0002-3986-1727" }, { "name": { "family": "Nowak", "given": "John B." }, "orcid": "0000-0002-5697-9807" }, { "name": { "family": "Peischl", "given": "Jeff" }, "orcid": "0000-0002-9320-7101" }, { "name": { "family": "Peterson", "given": "David A." }, "orcid": "0000-0002-9027-3779" }, { "name": { "family": "Piel", "given": "Felix" } }, { "name": { "family": "Richter", "given": "Dirk" } }, { "name": { "family": "Rickly", "given": "Pamela S." }, "orcid": "0000-0002-8459-869X" }, { "name": { "family": "Robinson", "given": "Michael A." }, "orcid": "0000-0003-0977-9148" }, { "name": { "family": "Rollins", "given": "Andrew W." }, "orcid": "0000-0002-1020-3966" }, { "name": { "family": "Ryerson", "given": "Thomas B." }, "orcid": "0000-0003-2800-7581" }, { "name": { "family": "Sekimoto", "given": "Kanako" } }, { "name": { "family": "Selimovic", "given": "Vanessa" } }, { "name": { "family": "Shingler", "given": "Taylor" }, "orcid": "0000-0003-4596-1027" }, { "name": { "family": "Soja", "given": "Amber J." }, "orcid": "0000-0001-8637-3040" }, { "name": { "family": "St. Clair", "given": "Jason M." }, "orcid": "0000-0002-9367-5749" }, { "name": { "family": "Tanner", "given": "David J." }, "orcid": "0000-0001-6445-8713" }, { "name": { "family": "Ullmann", "given": "Kirk" }, "orcid": "0000-0002-4724-9634" }, { "name": { "family": "Veres", "given": "Patrick R." }, "orcid": "0000-0001-7539-353X" }, { "name": { "family": "Walega", "given": "James" } }, { "name": { "family": "Warneke", "given": "Carsten" }, "orcid": "0000-0003-3811-8496" }, { "name": { "family": "Washenfelder", "given": "Rebecca A." }, "orcid": "0000-0002-8106-3702" }, { "name": { "family": "Weibring", "given": "Petter" } }, { "name": { "family": "Wisthaler", "given": "Armin" }, "orcid": "0000-0001-5050-3018" }, { "name": { "family": "Wolfe", "given": "Glenn M." }, "orcid": "0000-0001-6586-4043" }, { "name": { "family": "Womack", "given": "Caroline C." }, "orcid": "0000-0002-7101-9054" }, { "name": { "family": "Yokelson", "given": "Robert J." }, "orcid": "0000-0002-8415-6808" } ] }, "title": "Ozone chemistry in western U.S. wildfire plumes", "ispublished": "pub", "full_text_status": "public", "keywords": "Multidisciplinary", "note": "\u00a9 2021 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works. Distributed under a Creative Commons Attribution NonCommercial License 4.0 (CC BY-NC). \n\nReceived: 8 July 2021. Accepted: 20 October 2021. \n\nWe thank P. P. Papin for providing the background picture in Fig. 1 and R. Schwantes and M. Bela for helpful discussions. A.W. acknowledges support from ASAP-FFG-BMVIT and thanks T. Mikoviny and L. Tomsche for field support. \n\nL.X., K.T.V., H.A., J.D.C., and P.O.W. acknowledge NASA grants 80NSSC18K0660 and 80NSSC21K1704. I.B., M.M.C., G.I.G., A.L., J.A.N., J.P., P.S.R., M.A.R., and C.C.W. acknowledge the NOAA Cooperative Agreement with CIRES, NA17OAR4320101. G.M.W., T.F.H., J.M.S., J. Liao, and R.A.H. acknowledge NASA Tropospheric Composition and NOAA AC4 grant NA17OAR4310004. R.J.Y. and V.S. acknowledge NOAA grant NA16OAR4310100. A.F., D.R., J.W., and P.W. acknowledge NASA grant 80NSSC18K0628. D.A.P. acknowledges NASA grant 80HQTR18T0063. S.R.H. and K.U. acknowledge NASA grant 80NSSC18K0638. A.J.S. and E.M.G. acknowledge NASA grant 80NSSC18K0685. H.G., P.C.-J., and J.L.J. acknowledge NASA grants 80NSSC18K0630 and 80NSSC19K0124. F.P. acknowledges support from the EU (#674911, IMPACT ITN). C.D.H. acknowledges NASA grant 80NSSC18K0625. \n\nAuthor contributions: L.X. and P.O.W. designed the research. J.H.C., C.W., and D.A.P. designed the flight plans. L.X., J.D.C., K.T.V., H.A., P.O.W., I.B., S.S.B., P.C.-J., M.M.C., J.P.D., G.S.D., A.F., J.B.G., G.I.G., H.G., J.W.H., S.R.H, H.A.H., T.F.H., R.A.H., C.D.H., L.G.H., E.M.G., J.L.J., A.L.,Y.R.L., J. Liao, J. Lindaas, J.A.N., J.B.N., J.P., F.P., D.R., P.S.R., M.A.R., A.W.R., T.B.R., K.S., V.S., T.S., A.J.S., J.M.S., D.J.T., K.U., P.R.V., J.W., C.W., R.A.W., P.W., A.W., G.M.W., and C.C.W. conducted measurements. L.X. analyzed the data. L.X., P.O.W., and J.D.C. wrote the paper. R.J.Y. provided critical context on fire chemistry. \n\nThe authors declare that they have no competing interests. \n\nData and materials availability: All data needed to evaluate the conclusions in the paper are present in the paper and/or the Supplementary Materials. FIREX-AQ data are available at www-air.larc.nasa.gov/cgi-bin/ArcView/firexaq.\n\nPublished - sciadv.abl3648.pdf
Supplemental Material - sciadv.abl3648_sm.pdf
", "abstract": "Wildfires are a substantial but poorly quantified source of tropospheric ozone (O\u2083). Here, to investigate the highly variable O\u2083 chemistry in wildfire plumes, we exploit the in situ chemical characterization of western wildfires during the FIREX-AQ flight campaign and show that O\u2083 production can be predicted as a function of experimentally constrained OH exposure, volatile organic compound (VOC) reactivity, and the fate of peroxy radicals. The O\u2083 chemistry exhibits rapid transition in chemical regimes. Within a few daylight hours, the O\u2083 formation substantially slows and is largely limited by the abundance of nitrogen oxides (NO\u2093). This finding supports previous observations that O\u2083 formation is enhanced when VOC-rich wildfire smoke mixes into NO\u2093-rich urban plumes, thereby deteriorating urban air quality. Last, we relate O\u2083 chemistry to the underlying fire characteristics, enabling a more accurate representation of wildfire chemistry in atmospheric models that are used to study air quality and predict climate.", "date": "2021-12-10", "date_type": "published", "publication": "Science Advances", "volume": "7", "number": "50", "publisher": "American Association for the Advancement of Science", "pagerange": "Art. No. eabl3648", "id_number": "CaltechAUTHORS:20211209-456370000", "issn": "2375-2548", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20211209-456370000", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "80NSSC18K0660" }, { "agency": "NASA", "grant_number": "80NSSC21K1704" }, { "agency": "National Oceanic and Atmospheric Administration (NOAA)", "grant_number": "NA17OAR4320101" }, { "agency": "National Oceanic and Atmospheric Administration (NOAA)", "grant_number": "NA17OAR4310004" }, { "agency": "National Oceanic and Atmospheric Administration (NOAA)", "grant_number": "NA16OAR4310100" }, { "agency": "NASA", "grant_number": "80NSSC18K0628" }, { "agency": "NASA", "grant_number": "80HQTR18T0063" }, { "agency": "NASA", "grant_number": "80NSSC18K0638" }, { "agency": "NASA", "grant_number": "80NSSC18K0685" }, { "agency": "NASA", "grant_number": "80NSSC18K0630" }, { "agency": "NASA", "grant_number": "80NSSC19K0124" }, { "agency": "European Research Council (ERC)", "grant_number": "674911" }, { "agency": "NASA", "grant_number": "80NSSC18K0625" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1126/sciadv.abl3648", "primary_object": { "basename": "sciadv.abl3648.pdf", "url": "https://authors.library.caltech.edu/records/8hjh5-avx78/files/sciadv.abl3648.pdf" }, "related_objects": [ { "basename": "sciadv.abl3648_sm.pdf", "url": "https://authors.library.caltech.edu/records/8hjh5-avx78/files/sciadv.abl3648_sm.pdf" } ], "resource_type": "article", "pub_year": "2021", "author_list": "Xu, Lu; Crounse, John D.; et el." }, { "id": "https://authors.library.caltech.edu/records/5n0s7-76p22", "eprint_id": 111955, "eprint_status": "archive", "datestamp": "2023-08-20 06:00:13", "lastmod": "2023-10-23 20:50:02", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Van-Rooy-Paul", "name": { "family": "Van Rooy", "given": "Paul" }, "orcid": "0000-0003-1193-0994" }, { "id": "Tasnia-Afsara", "name": { "family": "Tasnia", "given": "Afsara" }, "orcid": "0000-0002-3048-5083" }, { "id": "Barletta-Barbara", "name": { "family": "Barletta", "given": "Barbara" }, "orcid": "0000-0003-3046-014X" }, { "id": "Buenconsejo-Reina-S", "name": { "family": "Buenconsejo", "given": "Reina" }, "orcid": "0000-0002-0162-905X" }, { "id": "Crounse-John-D", "name": { "family": "Crounse", "given": "John D." }, "orcid": "0000-0001-5443-729X" }, { "id": "Kenseth-Christopher-M", "name": { "family": "Kenseth", "given": "Christopher M." }, "orcid": "0000-0003-3188-2336" }, { "id": "Meinardi-Simone", "name": { "family": "Meinardi", "given": "Simone" }, "orcid": "0000-0003-4828-9889" }, { "id": "Murphy-Sara", "name": { "family": "Murphy", "given": "Sara" } }, { "id": "Parker-Harrison", "name": { "family": "Parker", "given": "Harrison" }, "orcid": "0000-0002-0041-2764" }, { "id": "Schulze-Benjamin-C", "name": { "family": "Schulze", "given": "Benjamin" }, "orcid": "0000-0002-6405-8872" }, { "id": "Seinfeld-J-H", "name": { "family": "Seinfeld", "given": "John H." }, "orcid": "0000-0003-1344-4068" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Blake-Donald-R", "name": { "family": "Blake", "given": "Donald R." }, "orcid": "0000-0002-8283-5014" }, { "id": "Barsanti-Kelley-C", "name": { "family": "Barsanti", "given": "Kelley C." }, "orcid": "0000-0002-6065-8643" } ] }, "title": "Observations of Volatile Organic Compounds in the Los Angeles Basin during COVID-19", "ispublished": "pub", "full_text_status": "public", "keywords": "VOCs, urban air quality, COVID-19, mobile source emissions, off-road emissions, VCPs", "note": "\u00a9 2021 American Chemical Society. \n\nReceived: July 9, 2021; Revised: September 27, 2021; Accepted: October 9, 2021; Published: October 28, 2021. \n\nThe authors would like to sincerely thank Joost de Gouw for conversations during the campaign period in which he shared his knowledge of the composition and chemistry in the LA Basin. The authors would also like to thank Joost de Gouw and Carsten Warneke for the quality data collected during the CalNex-2010 campaign and subsequent analysis of that data, which were foundational to this study. \n\nPVR, AT, KCB acknowledge funding support from NSF RAPID award #2030049. BB, SM, and DRB acknowledge funding support from NSF RAPID award #2030112. \n\nAuthor Contributions: The study was conceived by KCB, JHS, DRB, and POW. All authors contributed to data collection, analysis, and/or interpretation. The manuscript was written largely by PVR and KCB, with contributions from AT, BB, JDC, HP, PS, and POW. The manuscript was edited through contributions of all authors. All authors have given approval to the final version of the manuscript. \n\nThe authors declare no competing financial interest.\n\nSupplemental Material - sp1c00248_si_001.xlsx
Supplemental Material - sp1c00248_si_002.pdf
", "abstract": "Volatile organic compounds (VOCs) were measured in the Los Angeles (LA) Basin from mid-April to mid-July 2020 during the COVID-19 pandemic, as a part of the Los Angeles Air Quality Campaign (LAAQC). VOCs were quantified in over 450 samples using one- and two-dimensional gas chromatography with different detectors; mixing ratios were determined for 150 compounds associated with on- and off-road mobile, volatile chemical product, and biogenic sources. During the sampling period, traffic counts increased from \u223c55% to \u223c80% of pre-COVID levels. While the average afternoon combustion-derived VOCs and carbon monoxide (CO) mixing ratios did not change significantly between April\u2013May and June\u2013July, there was a shift in the distribution to higher mixing ratios in June\u2013July, particularly for VOCs associated with gasoline evaporation. Compared to observations made in the last major air quality campaign in the LA Basin (CalNex-2010), emission ratios for 40 compounds relative to acetylene (VOC/acetylene) have remained similar, while emission ratios relative to CO (VOC/CO) have dropped to \u223c60% of their 2010 values. This divergence in trends suggests that whereas mobile sources are still the dominant source of the combustion-derived VOCs measured in the LA Basin, there has been a shift in the mobile source sectors, with a growing contribution from sources that have lower CO/acetylene emission ratios, including off-road equipment and vehicles. In addition to the observed shift in source sector contributions, estimated OH exposure was 70\u2013120% higher than in 2010.", "date": "2021-11-18", "date_type": "published", "publication": "ACS Earth and Space Chemistry", "volume": "5", "number": "11", "publisher": "American Chemical Society", "pagerange": "3045-3055", "id_number": "CaltechAUTHORS:20211118-233559021", "issn": "2472-3452", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20211118-233559021", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "AGS-2030049" }, { "agency": "NSF", "grant_number": "AGS-2030112" } ] }, "local_group": { "items": [ { "id": "COVID-19" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1021/acsearthspacechem.1c00248", "primary_object": { "basename": "sp1c00248_si_001.xlsx", "url": "https://authors.library.caltech.edu/records/5n0s7-76p22/files/sp1c00248_si_001.xlsx" }, "related_objects": [ { "basename": "sp1c00248_si_002.pdf", "url": "https://authors.library.caltech.edu/records/5n0s7-76p22/files/sp1c00248_si_002.pdf" } ], "resource_type": "article", "pub_year": "2021", "author_list": "Van Rooy, Paul; Tasnia, Afsara; et el." }, { "id": "https://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.edu/records/vfg98-9zt14", "eprint_id": 112314, "eprint_status": "archive", "datestamp": "2023-08-22 11:38:46", "lastmod": "2023-10-23 19:40:54", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Wei-Dandan", "name": { "family": "Wei", "given": "Dandan" }, "orcid": "0000-0002-5597-6233" }, { "id": "Alwe-Hariprasad-D", "name": { "family": "Alwe", "given": "Hariprasad D." }, "orcid": "0000-0003-3851-4106" }, { "id": "Millet-Dylan-B", "name": { "family": "Millet", "given": "Dylan B." }, "orcid": "0000-0003-3076-125X" }, { "id": "Bottorff-Brandon", "name": { "family": "Bottorff", "given": "Brandon" } }, { "id": "Lew-Michelle", "name": { "family": "Lew", "given": "Michelle" } }, { "id": "Stevens-Philip-S", "name": { "family": "Stevens", "given": "Philip S." }, "orcid": "0000-0001-9899-4215" }, { "id": "Shutter-Joshua-D", "name": { "family": "Shutter", "given": "Joshua D." }, "orcid": "0000-0001-8291-8242" }, { "id": "Cox-Joshua-L", "name": { "family": "Cox", "given": "Joshua L." } }, { "id": "Keutsch-F-N", "name": { "family": "Keutsch", "given": "Frank N." } }, { "id": "Shi-Qianwen", "name": { "family": "Shi", "given": "Qianwen" }, "orcid": "0000-0001-5000-1499" }, { "id": "Kavassalis-Sarah-C", "name": { "family": "Kavassalis", "given": "Sarah C." }, "orcid": "0000-0001-5036-9138" }, { "id": "Murphy-Jennifer-G", "name": { "family": "Murphy", "given": "Jennifer G." }, "orcid": "0000-0001-8865-5463" }, { "id": "Vasquez-Krystal-T", "name": { "family": "Vasquez", "given": "Krystal T." }, "orcid": "0000-0003-4540-4212" }, { "id": "Allen-Hannah-M", "name": { "family": "Allen", "given": "Hannah M." }, "orcid": "0000-0002-4218-5133" }, { "id": "Praske-Eric", "name": { "family": "Praske", "given": "Eric" }, "orcid": "0000-0001-7169-4423" }, { "id": "Crounse-John-D", "name": { "family": "Crounse", "given": "John D." }, "orcid": "0000-0001-5443-729X" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Shepson-Paul-B", "name": { "family": "Shepson", "given": "Paul B." }, "orcid": "0000-0002-1726-3291" }, { "id": "Bui-Alexander-A-T", "name": { "family": "Bui", "given": "Alexander A. T." }, "orcid": "0000-0002-1205-1564" }, { "id": "Wallace-Henry-W", "name": { "family": "Wallace", "given": "Henry W." } }, { "id": "Griffin-R-J", "name": { "family": "Griffin", "given": "Robert J." }, "orcid": "0000-0001-7682-8769" }, { "id": "May-Nathaniel-W", "name": { "family": "May", "given": "Nathaniel W." }, "orcid": "0000-0002-8913-4827" }, { "id": "Connor-Megan", "name": { "family": "Connor", "given": "Megan" }, "orcid": "0000-0003-3266-4162" }, { "id": "Slade-Jonathan-H", "name": { "family": "Slade", "given": "Jonathan H." } }, { "id": "Pratt-Kerri-A", "name": { "family": "Pratt", "given": "Kerri A." }, "orcid": "0000-0003-4707-2290" }, { "id": "Wood-Ezra-C", "name": { "family": "Wood", "given": "Ezra C." }, "orcid": "0000-0002-9533-215X" }, { "id": "Rollings-Mathew", "name": { "family": "Rollings", "given": "Mathew" } }, { "id": "Deming-Benjamin-L", "name": { "family": "Deming", "given": "Benjamin L." }, "orcid": "0000-0003-3690-0046" }, { "id": "Anderson-Daniel-C", "name": { "family": "Anderson", "given": "Daniel C." }, "orcid": "0000-0002-9826-9811" }, { "id": "Steiner-Allison-L", "name": { "family": "Steiner", "given": "Allison L." }, "orcid": "0000-0002-3823-1512" } ] }, "title": "FORest Canopy Atmosphere Transfer (FORCAsT) 2.0: model updates and evaluation with observations at a mixed forest site", "ispublished": "pub", "full_text_status": "public", "keywords": "Pharmacology (medical)", "note": "\u00a9 Author(s) 2021. This work is distributed under the Creative Commons Attribution 4.0 License. \n\nReceived: 31 Mar 2021 \u2013 Discussion started: 23 Apr 2021 \u2013 Revised: 27 Jul 2021 \u2013 Accepted: 20 Sep 2021 \u2013 Published: 21 Oct 2021. \n\nAndrew P. Ault and Ryan Cook (University of Michigan) are acknowledged for field campaign assistance. Kerri A. Pratt, Nathaniel W. May, and Megan Connor acknowledge support from the University of Michigan MCubed 2.0 program and the Marian P. and David M. Gates Graduate Student Endowment Fund. The construction of the GC-HR-ToF-CIMS instrument was supported by the National Science Foundation (AGS-1428482), with additional NSF support (AGS-1240604) provided for the instrument field deployment to UMBS. Work performed by Krystal T. Vasquez and Hannah M. Allen was supported by the National Science Foundation Graduate Research Fellowship (NSF GRFP). Krystal T. Vasquez also acknowledges support from an Earl C. Anthony Fellowship in chemistry during an early portion of this study. The measurements of peroxy radicals were supported by NSF AGS-1443842 to the University of Massachusetts Amherst and AGS-1719918 to Drexel University. Work performed by Joshua D. Shutter and Joshua L. Cox was supported by the National Science Foundation Graduate Research Fellowship (NSF GRFP). Frank N. Keutsch acknowledges support by the National Science Foundation (AGS-1643306). \n\nThis research has been supported by the National Oceanic and Atmospheric Administration (grant no. NA18OAR4310116). \n\nAuthor contributions. ALS designed the study. DW implemented the model updates and performed the simulations and analysis. HDA and DBM provided the VOCs and turbulence data. BB, ML, and PSS provided the OH and HO2 data. JDS, JLC, and FNK provided the HCHO data. QS, SCK, and JGM provided the NOx data. KTV, HMA, EP, JDC, and POW provided above-canopy ISOPOOH and IHN data. JDC and POW provided a critical review on model evaluation regarding IHN. PBS provided the in-canopy IHN and MTN data and a critical review on the inclusion of liquid water content associated with organics. AATB, HWW, and RJG provided the AMS data. RJG provided a critical review on the MPMPO module. NWM, MC, JHS, and KAP provided the AIM data. KAP contributed to the calculation of liquid water content associated with inorganic species. ECW, MR, BLD, and DCA provided the ROx data. All authors contributed to model evaluation and the paper preparation. \n\nCode availability The codes of FORCAsT version 2.0 are available on Zenodo (https://doi.org/10.5281/zenodo.4776662, Steiner, 2021). \n\nData availability. Isoprene, monoterpenes, and MVK+MACR are available online at https://doi.org/10.13020/D6JQ3R (Alwe et al., 2019). The GC-HR-ToF-CIMS ISOPOOH, IEPOX, and IHN are available through https://data.caltech.edu/records/971 (Vasquez et al., 2018a, https://doi.org/10.22002/D1.971). \n\nThe authors declare that they have no conflict of interests. \n\nThis paper was edited by Gerd A. Folberth and reviewed by two anonymous referees.\n\nPublished - gmd-14-6309-2021.pdf
", "abstract": "Abstract. The FORCAsT (FORest Canopy Atmosphere Transfer) model version 1.0 is updated to FORCAsT 2.0 by implementing five major changes, including (1)\u00a0a\u00a0change to the operator splitting, separating chemistry from emission and dry deposition, which reduces the run time of the gas-phase chemistry by 70\u2009% and produces a more realistic in-canopy profile for isoprene; (2)\u00a0a\u00a0modification of the eddy diffusivity parameterization to produce greater and more realistic vertical mixing in the boundary layer, which ameliorates the unrealistic simulated end-of-day peaks in isoprene under well-mixed conditions and improves daytime air temperature; (3)\u00a0updates to dry deposition velocities with available measurements; (4)\u00a0implementation of the Reduced Caltech Isoprene Mechanism (RCIM) to reflect the current knowledge of isoprene oxidation; and (5)\u00a0extension of the aerosol module to include isoprene-derived secondary organic aerosol (iSOA) formation. Along with the operator splitting, modified vertical mixing, and dry deposition, RCIM improves the estimation of first-generation isoprene oxidation products (methyl vinyl ketone and methacrolein) and some second-generation products (such as isoprene epoxydiols). Inclusion of isoprene in the aerosol module in FORCAsT 2.0 leads to a 7\u2009% mass yield of iSOA. The most important iSOA precursors are IEPOX and tetrafunctionals, which together account for >86\u2009% of total iSOA. The iSOA formed from organic nitrates is more important in the canopy, accounting for 11\u2009% of the total iSOA. The tetrafunctionals compose up to 23\u2009% of the total iSOA formation, highlighting the importance of the fate (i.e., dry deposition and gas-phase chemistry) of later-generation isoprene oxidation products in estimating iSOA formation.", "date": "2021-10-21", "date_type": "published", "publication": "Geoscientific Model Development", "volume": "14", "number": "10", "publisher": "European Geosciences Union", "pagerange": "6309-6329", "id_number": "CaltechAUTHORS:20211208-951475000", "issn": "1991-9603", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20211208-951475000", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "University of Michigan" }, { "agency": "NSF", "grant_number": "AGS-1428482" }, { "agency": "NSF", "grant_number": "AGS-1240604" }, { "agency": "NSF Graduate Research Fellowship" }, { "agency": "Earl C. Anthony Fellowship" }, { "agency": "NSF", "grant_number": "AGS-1443842" }, { "agency": "NSF", "grant_number": "AGS-1719918" }, { "agency": "NSF", "grant_number": "AGS-1643306" }, { "agency": "National Oceanic and Atmospheric Administration (NOAA)", "grant_number": "NA18OAR4310116" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/gmd-14-6309-2021", "primary_object": { "basename": "gmd-14-6309-2021.pdf", "url": "https://authors.library.caltech.edu/records/vfg98-9zt14/files/gmd-14-6309-2021.pdf" }, "resource_type": "article", "pub_year": "2021", "author_list": "Wei, Dandan; Alwe, Hariprasad D.; et el." }, { "id": "https://authors.library.caltech.edu/records/c9y2s-21483", "eprint_id": 110374, "eprint_status": "archive", "datestamp": "2023-08-22 10:35:22", "lastmod": "2023-10-23 17:15:05", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Gonzalez-Yenny", "name": { "family": "Gonzalez", "given": "Yenny" }, "orcid": "0000-0001-5153-3972" }, { "name": { "family": "Commane", "given": "R\u00f3is\u00edn" }, "orcid": "0000-0003-1373-1550" }, { "name": { "family": "Manninen", "given": "Ethan" } }, { "name": { "family": "Daube", "given": "Bruce C." } }, { "name": { "family": "Schiferl", "given": "Luke D." }, "orcid": "0000-0002-5047-2490" }, { "name": { "family": "McManus", "given": "J. Barry" } }, { "name": { "family": "McKain", "given": "Kathryn" }, "orcid": "0000-0002-8323-5758" }, { "name": { "family": "Hintsa", "given": "Eric J." }, "orcid": "0000-0002-5289-630X" }, { "name": { "family": "Elkins", "given": "James W." }, "orcid": "0000-0003-4701-3100" }, { "name": { "family": "Montzka", "given": "Stephen A." }, "orcid": "0000-0002-9396-0400" }, { "name": { "family": "Sweeney", "given": "Colm" }, "orcid": "0000-0002-4517-0797" }, { "name": { "family": "Moore", "given": "Fred" }, "orcid": "0000-0002-8461-2535" }, { "name": { "family": "Jimenez", "given": "Jose L." }, "orcid": "0000-0001-6203-1847" }, { "name": { "family": "Campuzano Jost", "given": "Pedro" }, "orcid": "0000-0003-3930-010X" }, { "name": { "family": "Ryerson", "given": "Thomas B." }, "orcid": "0000-0003-2800-7581" }, { "name": { "family": "Bourgeois", "given": "Ilann" }, "orcid": "0000-0002-2875-1258" }, { "name": { "family": "Peischl", "given": "Jeff" }, "orcid": "0000-0002-9320-7101" }, { "name": { "family": "Thompson", "given": "Chelsea R." }, "orcid": "0000-0002-7332-9945" }, { "name": { "family": "Ray", "given": "Eric A." }, "orcid": "0000-0001-8727-9849" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Crounse-John-D", "name": { "family": "Crounse", "given": "John" }, "orcid": "0000-0001-5443-729X" }, { "id": "Kim-Michelle-J", "name": { "family": "Kim", "given": "Michelle" }, "orcid": "0000-0002-4922-4334" }, { "id": "Allen-Hannah-M", "name": { "family": "Allen", "given": "Hannah M." }, "orcid": "0000-0002-4218-5133" }, { "name": { "family": "Newman", "given": "Paul A." }, "orcid": "0000-0003-1139-2508" }, { "name": { "family": "Stephens", "given": "Britton B." }, "orcid": "0000-0002-1966-6182" }, { "name": { "family": "Apel", "given": "Eric C." }, "orcid": "0000-0001-9421-818X" }, { "name": { "family": "Hornbrook", "given": "Rebecca S." }, "orcid": "0000-0002-6304-6554" }, { "name": { "family": "Nault", "given": "Benjamin A." }, "orcid": "0000-0001-9464-4787" }, { "name": { "family": "Morgan", "given": "Eric" } }, { "name": { "family": "Wofsy", "given": "Steven C." }, "orcid": "0000-0002-3990-6737" } ] }, "title": "Impact of stratospheric air and surface emissions on tropospheric nitrous oxide during ATom", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 Author(s) 2021. This work is distributed under the Creative Commons Attribution 4.0 License. \n\nReceived: 25 February 2021 \u2013 Discussion started: 8 March 2021; Revised: 3 June 2021 \u2013 Accepted: 10 June 2021 \u2013 Published: 22 July 2021. \n\nWe would like to thank the ATom leadership team, the science team, and the NASA DC-8 pilot, technicians, and mechanics for their contribution and support during the mission. We thank Karl Froyd for the aerosol products during ATom that support this study. We also thank the National Aeronautics and Space Administration and the National Science Foundation for providing the financial support that made possible this study. \n\nThis research has been supported by the National Aeronautics and Space Administration (grant nos. NNX15AJ23G, NNX17AF54G, NNX15AG58A, NNX15AH33A, and 80NSSC19K0124) and the National Science Foundation (grant nos. 1852977, AGS-1547626, and AGS-1623745). \n\nData availability: Data from the ATom mission can be found in the NASA ESPO archive (https://espoarchive.nasa.gov/archive/browse/atom, last access: 10 February 2021), and in the ATom data repository at the NASA/ORNL DAAC (https://doi.org/10.3334/ORNLDAAC/1581, Wofsy et al., 2018). The QCLS N2O data is available at https://doi.org/10.3334/ORNLDAAC/1747 (Commane et al., 2020). \n\nSupplement: The supplement related to this article is available online at: https://doi.org/10.5194/acp-21-11113-2021-supplement. \n\nAuthor contributions: YG did the data analysis and wrote and revised the paper. SCW and RC actively contributed to the design of the study and data analysis. JBM designed the Neptune software for spectral re-analysis and contributed to the writing. RC and BCD performed and analyzed QCLS measurements of CH\u2084, N\u2082O, and CO and contributed to the discussions. EM and LDS contributed to the data analysis. KM performed and analyzed NOAA Picarro measurements of CH\u2084, CO, and CO\u2082. JWE, EJH, and FM performed and analyzed N\u2082O, SF\u2086, and CFC-12 measurements from PANTHER and UCATS instruments. FM, SM, and CS performed and analyzed N\u2082O measurements with the Programmable Flask Package Whole Air Sampler (PFP). POW, JC, MK, and HMA performed and analyzed the CIT-CIMS measurements of HCN and SO\u2082 shown here. KF performed and analyzed PALMS measurements. JLJ, PCJ, and BAN performed and analyzed HR-AMS measurements for a variety of aerosols. ER provided back trajectories for each minute during the flight tracks, and PN provided the GEOS5 FP meteorological products. TBR, IB, JP, and CRT performed and analyzed NO_yO\u2083 measurements of NO_y and O\u2083. BBS and EJM performed and analyzed AO2 and Medusa Whole Air Sampler measurements of O\u2082\u2009/\u2009N\u2082 and CO\u2082 and assisted with the interpretation. ECA and RSH performed and analyzed TOGA measurements of volatile organic compounds. All coauthors provided comments on the paper. \n\nThe authors declare that they have no conflict of interest. \n\nReview statement: This paper was edited by Andreas Engel and reviewed by three anonymous referees.\n\nPublished - acp-21-11113-2021.pdf
Supplemental Material - acp-21-11113-2021-supplement.pdf
", "abstract": "We measured the global distribution of tropospheric N\u2082O mixing ratios during the NASA airborne Atmospheric Tomography (ATom) mission. ATom measured concentrations of \u223c\u2009300 gas species and aerosol properties in 647 vertical profiles spanning the Pacific, Atlantic, Arctic, and much of the Southern Ocean basins, nearly from pole to pole, over four seasons (2016\u20132018). We measured N\u2082O concentrations at 1\u2009Hz using a quantum cascade laser spectrometer (QCLS). We introduced a new spectral retrieval method to account for the pressure and temperature sensitivity of the instrument when deployed on aircraft. This retrieval strategy improved the precision of our ATom QCLS N\u2082O measurements by a factor of three (based on the standard deviation of calibration measurements). Our measurements show that most of the variance of N\u2082O mixing ratios in the troposphere is driven by the influence of N\u2082O-depleted stratospheric air, especially at mid- and high latitudes. We observe the downward propagation of lower N\u2082O mixing ratios (compared to surface stations) that tracks the influence of stratosphere\u2013troposphere exchange through the tropospheric column down to the surface. The highest N\u2082O mixing ratios occur close to the Equator, extending through the boundary layer and free troposphere. We observed influences from a complex and diverse mixture of N\u2082O sources, with emission source types identified using the rich suite of chemical species measured on ATom and the geographical origin calculated using an atmospheric transport model. Although ATom flights were mostly over the oceans, the most prominent N\u2082O enhancements were associated with anthropogenic emissions, including from industry (e.g., oil and gas), urban sources, and biomass burning, especially in the tropical Atlantic outflow from Africa. Enhanced N\u2082O mixing ratios are mostly associated with pollution-related tracers arriving from the coastal area of Nigeria. Peaks of N\u2082O are often associated with indicators of photochemical processing, suggesting possible unexpected source processes. In most cases, the results show how difficult it is to separate the mixture of different sources in the atmosphere, which may contribute to uncertainties in the N\u2082O global budget. The extensive data set from ATom will help improve the understanding of N\u2082O emission processes and their representation in global models.", "date": "2021-07-22", "date_type": "published", "publication": "Atmospheric Chemistry and Physics", "volume": "21", "number": "14", "publisher": "European Geosciences Union", "pagerange": "11113-11132", "id_number": "CaltechAUTHORS:20210821-172128783", "issn": "1680-7324", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210821-172128783", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NNX15AJ23G" }, { "agency": "NASA", "grant_number": "NNX17AF54G" }, { "agency": "NASA", "grant_number": "NNX15AG58A" }, { "agency": "NASA", "grant_number": "NNX15AH33A" }, { "agency": "NASA", "grant_number": "80NSSC19K0124" }, { "agency": "NSF", "grant_number": "AGS-1852977" }, { "agency": "NSF", "grant_number": "AGS-1547626" }, { "agency": "NSF", "grant_number": "AGS-1623745" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/acp-21-11113-2021", "primary_object": { "basename": "acp-21-11113-2021-supplement.pdf", "url": "https://authors.library.caltech.edu/records/c9y2s-21483/files/acp-21-11113-2021-supplement.pdf" }, "related_objects": [ { "basename": "acp-21-11113-2021.pdf", "url": "https://authors.library.caltech.edu/records/c9y2s-21483/files/acp-21-11113-2021.pdf" } ], "resource_type": "article", "pub_year": "2021", "author_list": "Gonzalez, Yenny; Commane, R\u00f3is\u00edn; et el." }, { "id": "https://authors.library.caltech.edu/records/fdnnk-fc960", "eprint_id": 109703, "eprint_status": "archive", "datestamp": "2023-08-22 10:31:02", "lastmod": "2023-10-23 18:08:19", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Liu-Jun", "name": { "family": "Liu", "given": "Jun" } }, { "id": "Gunsch-Matthew-J", "name": { "family": "Gunsch", "given": "Matthew J." } }, { "id": "Moffett-Claire-E", "name": { "family": "Moffett", "given": "Claire E." } }, { "id": "Xu-Lu", "name": { "family": "Xu", "given": "Lu" }, "orcid": "0000-0002-0021-9876" }, { "id": "El-Asmar-Rime", "name": { "family": "El Asmar", "given": "Rime" } }, { "id": "Zhang-Qi", "name": { "family": "Zhang", "given": "Qi" }, "orcid": "0000-0002-5203-8778" }, { "id": "Watson-Thomas-B", "name": { "family": "Watson", "given": "Thomas B." } }, { "id": "Allen-Hannah-M", "name": { "family": "Allen", "given": "Hannah M." }, "orcid": "0000-0002-4218-5133" }, { "id": "Crounse-John-D", "name": { "family": "Crounse", "given": "John D." }, "orcid": "0000-0001-5443-729X" }, { "id": "St-Clair-Jason-M", "name": { "family": "St. Clair", "given": "Jason" }, "orcid": "0000-0002-9367-5749" }, { "id": "Kim-Michelle-J", "name": { "family": "Kim", "given": "Michelle" }, "orcid": "0000-0002-4922-4334" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Weber-Rodney-J", "name": { "family": "Weber", "given": "Rodney J." }, "orcid": "0000-0003-0765-8035" }, { "id": "Sheesley-Rebecca-J", "name": { "family": "Sheesley", "given": "Rebecca J." } }, { "id": "Pratt-Kerri-A", "name": { "family": "Pratt", "given": "Kerri A." }, "orcid": "0000-0003-4707-2290" } ] }, "title": "Hydroxymethanesulfonate (HMS) Formation during Summertime Fog in an Arctic Oil Field", "ispublished": "pub", "full_text_status": "public", "keywords": "Lipids, Anions, Liquids, Aerosols, Particulate matter", "note": "\u00a9 2021 American Chemical Society. \n\nReceived: May 9, 2021; Revised: June 16, 2021; Accepted: June 18, 2021. \n\nThis study was supported by the NOAA Climate Program Office and Atmospheric Chemistry, Carbon Cycle, and Climate Program through NA14OAR4310149 (University of Michigan) and NA14OAR4310150 (Baylor University) and a Department of Energy (DOE) Early Career Award (DE-SC0019172). The field work was also supported in part by the DOE Office of Biological and Environmental Research (BER) ARM Climate Research Facility (field campaign 2013-6660). This research was also supported by a National Academies of Sciences, Engineering, and Medicine Gulf Research Program Early-Career Research Fellowship (2000007270). Q.Z. was supported by funding from the DOE Atmospheric System Research Program (DE-SC0017041). R.J.W. and R.E.A. were supported by the NSF Navigating the New Arctic (NNA) program (ICER-1927778). Meteorological and greenhouse gas data were obtained from the ARM Climate Research Facility. DOE ARM, Sandia National Laboratory, AMF3 field operators, and the U.S. Air Force are thanked for logistical assistance at Oliktok Point, AK. Ningxin Wang (University of California, Davis, Davis, CA) is thanked for assistance in analyzing the ACSM data, and Thomas Hanisco (NASA Goddard) and Glenn Wolfe (University of Maryland Baltimore County) are acknowledged for HCHO data contributions. The aircraft data were supported by the NASA ATom Earth Venture Suborbital-2 Program; the authors thank the pilots, technicians, and mechanics for their support during the ATom flights. ATom SO2 observations were supported by NASA (NNX15AG61A). ATom HCHO observations were supported by the NASA Upper Atmospheric Research Program and the NASA Tropospheric Composition Program. ATOFMS data are available at the DOE ARM data archive (https://www.arm.gov/research/campaigns/amf2015saansa). The authors thank Shaojie Song for helpful discussions of the HMS production calculations. \n\nThe authors declare no competing financial interest.\n\nSupplemental Material - ez1c00357_si_001.pdf
", "abstract": "Hydroxymethanesulfonate (HMS) is produced in the aqueous-phase reaction of formaldehyde (HCHO) and sulfur dioxide (SO\u2082) and has been proposed as a significant contributor to midlatitude wintertime pollution events. Here we report HMS detection within submicrometer atmospheric aerosols during frequent late summer, regional fog events in an Arctic oil field. The number fraction of individual particles containing HMS increased during fog periods, consistent with aqueous-phase formation. The single-particle mass spectra showed the primary particle signature (oil field emissions), plus secondary oxidized organics and sulfate, consistent with aqueous-phase processing. HMS mass concentrations ranged from below the ion chromatography limit of detection (0.3 ng/m\u00b3) to 1.6 ng/m\u00b3, with sulfate concentrations of 37\u2013222 ng/m\u00b3. HCHO and SO\u2082 measurements suggest that the fog HMS production rate is \u223c10 times higher in the oil fields than in the upwind Beaufort Sea. Aqueous-phase reactions of local oil field emissions during frequent summertime regional fog events likely have downwind impacts on Arctic aerosol composition. The potential for fog-based HMS production was estimated to be an order of magnitude higher in Fairbanks and Anchorage, AK, than in the oil fields and may explain the missing organosulfate source contributing to Fairbanks air quality.", "date": "2021-07-13", "date_type": "published", "publication": "Environmental Science and Technology Letters", "volume": "8", "number": "7", "publisher": "American Chemical Society", "pagerange": "511-518", "id_number": "CaltechAUTHORS:20210701-170842679", "issn": "2328-8930", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210701-170842679", "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": "NA14OAR4310149" }, { "agency": "National Oceanic and Atmospheric Administration (NOAA)", "grant_number": "NA14OAR4310150" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0019172" }, { "agency": "National Academies of Sciences, Engineering, and Medicine Gulf Research", "grant_number": "2000007270" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0017041" }, { "agency": "NSF", "grant_number": "ICER-1927778" }, { "agency": "NASA", "grant_number": "NNX15AG61A" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1021/acs.estlett.1c00357", "primary_object": { "basename": "ez1c00357_si_001.pdf", "url": "https://authors.library.caltech.edu/records/fdnnk-fc960/files/ez1c00357_si_001.pdf" }, "resource_type": "article", "pub_year": "2021", "author_list": "Liu, Jun; Gunsch, Matthew J.; et el." }, { "id": "https://authors.library.caltech.edu/records/bze4a-x5817", "eprint_id": 108990, "eprint_status": "archive", "datestamp": "2023-08-22 09:20:09", "lastmod": "2023-10-23 16:54:08", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Rickly-Pamela-S", "name": { "family": "Rickly", "given": "Pamela S." }, "orcid": "0000-0002-8459-869X" }, { "id": "Xu-Lu", "name": { "family": "Xu", "given": "Lu" }, "orcid": "0000-0002-0021-9876" }, { "id": "Crounse-J-D", "name": { "family": "Crounse", "given": "John D." }, "orcid": "0000-0001-5443-729X" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Rollins-Andrew-W", "name": { "family": "Rollins", "given": "Andrew W." }, "orcid": "0000-0002-1020-3966" } ] }, "title": "Improvements to a laser-induced fluorescence instrument for measuring SO\u2082 \u2013 impact on accuracy and precision", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 Author(s) 2021. This work is distributed under the Creative Commons Attribution 4.0 License. \n\nReceived: 27 Oct 2020 \u2013 Discussion started: 09 Nov 2020 \u2013 Revised: 01 Feb 2021 \u2013 Accepted: 12 Feb 2021 \u2013 Published: 26 Mar 2021. \n\nData availability: The data collected for FIREX-AQ are available from the NASA/NOAA FIREX-AQ data archive at https://www-air.larc.nasa.gov/cgi-bin/ArcView/firexaq (last access: 23 April 2019, NASA/NOAA, 2019). The data collected for ATom-4 are available from the NASA ESPO data archive at https://espoarchive.nasa.gov/archive/browse/atom/id14 (last access: 23 April 2019, NASA, 2019). \n\nAuthor contributions: The research was designed by PSR and AWR. Measurements were taken by PSR, AWR, LX, JDC, and POW. The paper was written by PSR, with contributions from all coauthors. \n\nThe authors declare that they have no conflict of interest. \n\nWe would like to thank the NASA DC-8 crew and management team for their support during ATom-4 and FIREX-AQ integration and flights. We thank Michelle Kim and Hannah Allen for operating CIT's CIMS instrument during ATom-4. \n\nThis research was funded by the ATom investigation, under NASA's Earth Venture program, and the FIREX-AQ investigation, under NASA's Atmospheric Compostion: Upper Atmospheric Composition Observations program CE8 (CIT grant nos. NNX15AG61A and 80NSSC18K0660, respectively). \n\nReview statement: This paper was edited by Dwayne Heard and reviewed by two anonymous referees.\n\nPublished - amt-14-2429-2021.pdf
", "abstract": "This work describes key improvements made to the in situ laser-induced fluorescence instrument for measuring sulfur dioxide (SO\u2082) that was originally described by Rollins et al. (2016). Here, we report measurements of the SO\u2082 fluorescence emission spectrum. These measurements allow for the determination of the most appropriate bandpass filters to optimize the fluorescence signal, while reducing the instrumental background. Because many aromatic species fluoresce in the same spectral region as SO\u2082, fluorescence spectra were also measured for naphthalene and anisole to determine if ambient SO\u2082 measurements could be biased in the presence of such species. Improvement in the laser system resulted in better tunability, and a significant reduction in the 216.9\u2009nm laser linewidth. This increases the online/offline signal ratio which, in turn, improves the precision and specificity of the measurement. The effects of these improvements on the instrumental sensitivity were determined by analyzing the signal and background of the instrument, using varying optical bandpass filter ranges and cell pressures and calculating the resulting limit of detection. As a result, we report an improvement to the instrumental sensitivity by as much as 50\u2009%.", "date": "2021-03-26", "date_type": "published", "publication": "Atmospheric Measurement Techniques", "volume": "14", "number": "3", "publisher": "European Geosciences Union", "pagerange": "2429-2439", "id_number": "CaltechAUTHORS:20210506-105320666", "issn": "1867-8548", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210506-105320666", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NNX15AG61A" }, { "agency": "NASA", "grant_number": "80NSSC18K0660" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/amt-14-2429-2021", "primary_object": { "basename": "amt-14-2429-2021.pdf", "url": "https://authors.library.caltech.edu/records/bze4a-x5817/files/amt-14-2429-2021.pdf" }, "resource_type": "article", "pub_year": "2021", "author_list": "Rickly, Pamela S.; Xu, Lu; et el." }, { "id": "https://authors.library.caltech.edu/records/awmsf-zrs47", "eprint_id": 108005, "eprint_status": "archive", "datestamp": "2023-08-22 09:16:38", "lastmod": "2023-10-23 16:52:55", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Hedelius-Jacob-K", "name": { "family": "Hedelius", "given": "Jacob K." }, "orcid": "0000-0003-2025-7519" }, { "id": "Toon-Geoffrey-C", "name": { "family": "Toon", "given": "Geoffrey C." }, "orcid": "0000-0003-4174-7541" }, { "id": "Buchholz-Rebecca-R", "name": { "family": "Buchholz", "given": "Rebecca R." }, "orcid": "0000-0001-8124-2455" }, { "id": "Iraci-Laura-T", "name": { "family": "Iraci", "given": "Laura T." }, "orcid": "0000-0002-2859-5259" }, { "id": "Podolske-James-R", "name": { "family": "Podolske", "given": "James R." }, "orcid": "0000-0003-2771-5375" }, { "id": "Roehl-Coleen-M", "name": { "family": "Roehl", "given": "Coleen M." }, "orcid": "0000-0001-5383-8462" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Worden-Helen-M", "name": { "family": "Worden", "given": "Helen M." }, "orcid": "0000-0002-5949-9307" }, { "id": "Wunch-Debra", "name": { "family": "Wunch", "given": "Debra" }, "orcid": "0000-0002-4924-0377" } ] }, "title": "Regional and Urban Column CO Trends and Anomalies as Observed by MOPITT Over 16 Years", "ispublished": "pub", "full_text_status": "public", "keywords": "anthropogenic emissions; biomass burning; carbon monoxide; MOPITT; regional atmospheric trends; TCCON", "note": "\u00a9 2021 American Geophysical Union. \n\nIssue Online: 01 March 2021; Version of Record online: 01 March 2021; Accepted manuscript online: 10 February 2021; Manuscript accepted: 27 October 2020; Manuscript received: 25 September 2020. \n\nThe authors thank the MOPITT team and TCCON partners for providing high quality CO retrievals to the scientific community. The author thank Jennifer Murphy and Xuesong Zhang for helpful conversations. This study was funded by the Canadian Space Agency Earth System Science Data Analyses program (grant #16SUASCOBF). \n\nThe Authors declare no conflict of interest. \n\nData Availability Statement: MOPITT data may be obtained from the NASA Earthdata website (https://search.earthdata.nasa.gov/search/granules?p=C1288777617\u2010LARC, last access: October 30, 2020). TCCON data were obtained through the TCCON data archive hosted by CaltechData (https://tccondata.org/, last access: June 19, 2019). Ground\u2010based MkIV data were obtained through the JPL MkIV website (https://mark4sun.jpl.nasa.gov, last access: June 19, 2019).\n\nPublished - 2020JD033967.pdf
Supplemental Material - 2020jd033967-sup-0001-text_si-s01.pdf
", "abstract": "Atmospheric carbon monoxide (CO) concentrations have decreased since the beginning of the century, and the rate of decrease depends on the region. Depending on how regions are chosen, their boundaries may not always align with where there are differences in trends. To address this, we calculate trends within 0.4\u00b0 \u00d7 0.4\u00b0 grid cells independently throughout the globe using satellite CO retrievals from the Measurements Of Pollution In The Troposphere (MOPITT) satellite instrument from 2002 to 2017. These trends are found with the caveat that there are large singular biomass burning events somewhere nearly every year, and we include examples of large column CO anomalies during sporadic but large burning events in the North American and Eurasian boreal forests, the Amazon, Africa, and Indonesia. CO trends behave similarly within regions that span about a few thousand kilometers. Using TransCom region definitions, we find average trends between \u22120.9 and 0.1 ppb year\u207b\u00b9 (about \u22120.9 to 0.1% year\u207b\u00b9) for 2002\u20132017. Over 5\u2010year subsets, trends in TransCom regions vary between \u22123.6 and 1.8 ppb year\u207b\u00b9. This substantial spatial and temporal variability in trends is in agreement with other studies. With an understanding of regional trends, we compare with trends from urban areas. Generally, CO trends within urban areas are indistinguishable from regional trends. This may be because of a combination of noise in the data, the large footprint for MOPITT, or because anthropogenic CO reduction measures were implemented before the MOPITT record began. We provide case studies for a few cities, such as Los Angeles, and find long\u2010term variation in the rate of change of column CO.", "date": "2021-03-16", "date_type": "published", "publication": "Journal of Geophysical Research. Atmospheres", "volume": "126", "number": "5", "publisher": "American Geophysical Union", "pagerange": "Art. No. e2020JD033967", "id_number": "CaltechAUTHORS:20210211-125216415", "issn": "2169-897X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210211-125216415", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Canadian Space Agency (CSA)", "grant_number": "16SUASCOBF" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2020jd033967", "primary_object": { "basename": "2020JD033967.pdf", "url": "https://authors.library.caltech.edu/records/awmsf-zrs47/files/2020JD033967.pdf" }, "related_objects": [ { "basename": "2020jd033967-sup-0001-text_si-s01.pdf", "url": "https://authors.library.caltech.edu/records/awmsf-zrs47/files/2020jd033967-sup-0001-text_si-s01.pdf" } ], "resource_type": "article", "pub_year": "2021", "author_list": "Hedelius, Jacob K.; Toon, Geoffrey C.; et el." }, { "id": "https://authors.library.caltech.edu/records/8tepq-rrg44", "eprint_id": 108481, "eprint_status": "archive", "datestamp": "2023-08-22 08:37:56", "lastmod": "2023-10-23 19:31:29", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Lorente-Alba", "name": { "family": "Lorente", "given": "Alba" }, "orcid": "0000-0002-2287-4687" }, { "id": "Borsdorff-Tobias", "name": { "family": "Borsdorff", "given": "Tobias" }, "orcid": "0000-0002-4421-0187" }, { "id": "Butz-Andre", "name": { "family": "Butz", "given": "Andre" }, "orcid": "0000-0003-0593-1608" }, { "id": "Hasekamp-Otto", "name": { "family": "Hasekamp", "given": "Otto" } }, { "id": "aan-de-Brugh-Joost", "name": { "family": "aan de Brugh", "given": "Joost" } }, { "id": "Schneider-Andreas", "name": { "family": "Schneider", "given": "Andreas" } }, { "id": "Wu-Lianghai", "name": { "family": "Wu", "given": "Lianghai" }, "orcid": "0000-0001-7797-1719" }, { "id": "Hase-Frank", "name": { "family": "Hase", "given": "Frank" } }, { "id": "Kivi-Rigel", "name": { "family": "Kivi", "given": "Rigel" }, "orcid": "0000-0001-8828-2759" }, { "id": "Wunch-Debra", "name": { "family": "Wunch", "given": "Debra" }, "orcid": "0000-0002-4924-0377" }, { "id": "Pollard-David-F", "name": { "family": "Pollard", "given": "David F." }, "orcid": "0000-0001-9923-2984" }, { "id": "Shiomi-Kei", "name": { "family": "Shiomi", "given": "Kei" } }, { "id": "Deutscher-Nicholas-M", "name": { "family": "Deutscher", "given": "Nicholas M." }, "orcid": "0000-0002-2906-2577" }, { "id": "Velazco-Voltaire-A", "name": { "family": "Velazco", "given": "Voltaire A." }, "orcid": "0000-0002-1376-438X" }, { "id": "Roehl-Coleen-M", "name": { "family": "Roehl", "given": "Coleen M." } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Warneke-Thorsten", "name": { "family": "Warneke", "given": "Thorsten" }, "orcid": "0000-0001-5185-3415" }, { "id": "Landgraf-Jochen", "name": { "family": "Landgraf", "given": "Jochen" }, "orcid": "0000-0002-6069-0598" } ] }, "title": "Methane retrieved from TROPOMI: improvement of the data product and validation of the first 2 years of measurements", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 Author(s) 2021. This work is distributed under\nthe Creative Commons Attribution 4.0 License.\nPublished by Copernicus Publications on behalf of the European Geosciences Union.\n\nReceived: 13 July 2020 \u2013 Discussion started: 5 August 2020;\nRevised: 9 November 2020 \u2013 Accepted: 24 November 2020 \u2013 Published: 28 January 2021.\n\nThe TROPOMI data processing was carried out on the Dutch National e-Infrastructure with the support of the SURF Cooperative.\n\nData availability:\nThe SRON S5P-RemoTeC scientific TROPOMI CH4 dataset from this study is available for download at https://doi.org/10.5281/zenodo.4447228 (Lorente et al., 2021) or at https://ftp.sron.nl/open-access-data-2/TROPOMI/tropomi/ch4/14_14_Lorente_et_al_2020_AMTD/ (last access: 27 January 2021). TCCON data are available from the TCCON Data Archive: Total Carbon Column Observing Network (TCCON), available at https://tccondata.org/ (last access: 12 January 2021).\n\nAuthor contributions:\nAL, TB, OH, JdB, AS, AB and JL provided the TROPOMI CH4 retrieval and data analysis. The TCCON partners provided the validation datasets. AL wrote the original draft with input from TB and JL. All authors discussed the results and reviewed and edited the paper.\n\nCompeting interests:\nThe authors declare that they have no conflict of interest.\n\nDisclaimer:\nThe presented work has been performed in the frame of Sentinel-5 Precursor Validation Team (S5PVT) or Level 1/Level 2 Product Working Group activities. Results are based on preliminary (not fully calibrated or validated) Sentinel-5 Precursor data that will still change. The results are based on S5P L1B version 1 data. Plots and data contain modified Copernicus Sentinel data, processed by SRON.\n\nFinancial support:\nFunding through the TROPOMI national program from the NSO and Methane+ is acknowledged. Darwin and Wollongong TCCON sites are funded by the Australian Research Council (DP140101552, DP160101598, LE0668470) and NASA (NAG5-12247, NNG05-GD07G). Nicholas M. Deutscher is supported by an ARC Future Fellowship (FT180100327).\n\nReview statement:\nThis paper was edited by Dominik Brunner and reviewed by two anonymous referees.\n\nPublished - amt-14-665-2021.pdf
", "abstract": "The TROPOspheric Monitoring Instrument (TROPOMI) on board the Sentinel 5 Precursor (S5-P) satellite provides methane (CH\u2084) measurements with high accuracy and exceptional temporal and spatial resolution and sampling. TROPOMI CH\u2084 measurements are highly valuable to constrain emissions inventories and for trend analysis, with strict requirements on the data quality. This study describes the improvements that we have implemented to retrieve CH\u2084 from TROPOMI using the RemoTeC full-physics algorithm. The updated retrieval algorithm features a constant regularization scheme of the inversion that stabilizes the retrieval and yields less scatter in the data and includes a higher resolution surface altitude database. We have tested the impact of three state-of-the-art molecular spectroscopic databases (HITRAN 2008, HITRAN 2016 and Scientific Exploitation of Operational Missions \u2013 Improved Atmospheric Spectroscopy Databases SEOM-IAS) and found that SEOM-IAS provides the best fitting results. The most relevant update in the TROPOMI XCH\u2084 data product is the implementation of an a posteriori correction fully independent of any reference data that is more accurate and corrects for the underestimation at low surface albedo scenes and the overestimation at high surface albedo scenes. After applying the correction, the albedo dependence is removed to a large extent in the TROPOMI versus satellite (Greenhouse gases Observing SATellite \u2013 GOSAT) and TROPOMI versus ground-based observations (Total Carbon Column Observing Network \u2013 TCCON) comparison, which is an independent verification of the correction scheme. We validate 2 years of TROPOMI CH\u2084 data that show the good agreement of the updated TROPOMI CH\u2084 with TCCON (\u22123.4\u2009\u00b1\u20095.6\u2009ppb) and GOSAT (\u221210.3\u2009\u00b1\u200916.8\u2009ppb) (mean bias and standard deviation). Low- and high-albedo scenes as well as snow-covered scenes are the most challenging for the CH\u2084 retrieval algorithm, and although the a posteriori correction accounts for most of the bias, there is a need to further investigate the underlying cause.", "date": "2021-01-28", "date_type": "published", "publication": "Atmospheric Measurement Techniques", "volume": "14", "number": "1", "publisher": "European Geosciences Union", "pagerange": "665-684", "id_number": "CaltechAUTHORS:20210318-105725134", "issn": "1867-8548", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210318-105725134", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Netherlands Space Office (NSO)" }, { "agency": "Australian Research Council", "grant_number": "DP140101552" }, { "agency": "Australian Research Council", "grant_number": "DP160101598" }, { "agency": "Australian Research Council", "grant_number": "LE0668470" }, { "agency": "NASA", "grant_number": "NAG5-12247" }, { "agency": "NASA", "grant_number": "NNG05-GD07G" }, { "agency": "Australian Research Council", "grant_number": "FT180100327" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/amt-14-665-2021", "primary_object": { "basename": "amt-14-665-2021.pdf", "url": "https://authors.library.caltech.edu/records/8tepq-rrg44/files/amt-14-665-2021.pdf" }, "resource_type": "article", "pub_year": "2021", "author_list": "Lorente, Alba; Borsdorff, Tobias; et el." }, { "id": "https://authors.library.caltech.edu/records/sd52z-yvd21", "eprint_id": 107511, "eprint_status": "archive", "datestamp": "2023-08-22 08:35:52", "lastmod": "2023-10-23 15:57:59", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Chen-Jing", "name": { "family": "Chen", "given": "Jing" }, "orcid": "0000-0001-6545-6197" }, { "id": "M\u00f8ller-Kristian-H", "name": { "family": "M\u00f8ller", "given": "Kristian H." }, "orcid": "0000-0001-8070-8516" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Kjaergaard-Henrik-G", "name": { "family": "Kjaergaard", "given": "Henrik G." }, "orcid": "0000-0002-7275-8297" } ] }, "title": "Unimolecular Reactions Following Indoor and Outdoor Limonene Ozonolysis", "ispublished": "pub", "full_text_status": "public", "keywords": "Redox reactions, Chemical reactions, Oxidation, Molecular structure, Organic reactions", "note": "\u00a9 2021 American Chemical Society. \n\nReceived: November 2, 2020; Revised: December 21, 2020; Published: January 12, 2021. \n\nThe authors are grateful for the funding from the Independent Research Fund Denmark and the University of Copenhagen. This work is supported by the Alfred P. Sloan Foundation under Award no. G-2019-12281 and the California Institute of Technology. \n\nThe authors declare no competing financial interest.\n\nSupplemental Material - jp0c09882_si_001.pdf
", "abstract": "Limonene is one of the monoterpenes with the largest biogenic emissions and is also widely used as an additive in cleaning products, leading to significant indoor emissions. Studies have found that the formation of secondary organic aerosols (SOAs) from limonene oxidation has important implications for indoor air quality. Although ozonolysis is considered the major limonene oxidation pathway under most indoor conditions, little is known about the mechanisms for SOA formation from limonene ozonolysis. Here, we calculate the rate coefficients of the possible unimolecular reactions of the first-generation peroxy radicals formed by limonene ozonolysis using a high-level multiconformer transition state theory approach. We find that all of the peroxy radicals formed initially in the ozonolysis of limonene react unimolecularly with rates that are competitive both indoors and outdoors, except under highly polluted conditions. Differences in reactivity between the peroxy radicals from ozonolysis and those formed by OH, NO\u2083, and Cl oxidation are discussed. Finally, we sketch possible oxidation mechanisms for the different peroxy radicals under both indoor and pristine atmospheric conditions and in more polluted environments. In environments with low concentrations of HO\u2082 and NO, efficient autoxidation will lead to the formation of highly oxygenated organic compounds and thus likely aid in the growth of SOA.", "date": "2021-01-21", "date_type": "published", "publication": "Journal of Physical Chemistry A", "volume": "125", "number": "2", "publisher": "American Chemical Society", "pagerange": "669-680", "id_number": "CaltechAUTHORS:20210115-132720425", "issn": "1089-5639", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210115-132720425", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Independent Research Fund Denmark" }, { "agency": "University of Copenhagen" }, { "agency": "Alfred P. Sloan Foundation", "grant_number": "G-2019-12281" }, { "agency": "Caltech" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1021/acs.jpca.0c09882", "primary_object": { "basename": "jp0c09882_si_001.pdf", "url": "https://authors.library.caltech.edu/records/sd52z-yvd21/files/jp0c09882_si_001.pdf" }, "resource_type": "article", "pub_year": "2021", "author_list": "Chen, Jing; M\u00f8ller, Kristian H.; et el." }, { "id": "https://authors.library.caltech.edu/records/cmrq4-fbg67", "eprint_id": 108237, "eprint_status": "archive", "datestamp": "2023-08-22 08:06:19", "lastmod": "2023-10-23 16:33:41", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Fried-Alan-E", "name": { "family": "Fried", "given": "Alan" } }, { "name": { "family": "Walega", "given": "James" } }, { "name": { "family": "Weibring", "given": "Petter" } }, { "name": { "family": "Richter", "given": "Dirk" } }, { "name": { "family": "Simpson", "given": "Isobel J." }, "orcid": "0000-0002-4211-1126" }, { "name": { "family": "Blake", "given": "Donald R." }, "orcid": "0000-0002-8283-5014" }, { "name": { "family": "Blake", "given": "Nicola J." } }, { "name": { "family": "Meinardi", "given": "Simone" }, "orcid": "0000-0003-4828-9889" }, { "name": { "family": "Barletta", "given": "Barbara" } }, { "name": { "family": "Hughes", "given": "Stacey C." } }, { "name": { "family": "Crawford", "given": "James H." } }, { "name": { "family": "Diskin", "given": "G." }, "orcid": "0000-0002-3617-0269" }, { "name": { "family": "Barrick", "given": "John" } }, { "name": { "family": "Hair", "given": "Johnathan" }, "orcid": "0000-0002-9672-1237" }, { "name": { "family": "Fenn", "given": "Marta" }, "orcid": "0000-0001-6088-6200" }, { "name": { "family": "Wisthaler", "given": "Armin" } }, { "name": { "family": "Mikoviny", "given": "Tomas" } }, { "name": { "family": "Woo", "given": "Jung-Hun" } }, { "name": { "family": "Park", "given": "Minwoo" } }, { "name": { "family": "Kim", "given": "Jinseok" } }, { "name": { "family": "Min", "given": "Kyung-Eun" } }, { "name": { "family": "Jeong", "given": "Seokhan" } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Kim-Michelle-J", "name": { "family": "Kim", "given": "Michelle J." }, "orcid": "0000-0002-4922-4334" }, { "id": "Crounse-J-D", "name": { "family": "Crounse", "given": "John D." }, "orcid": "0000-0001-5443-729X" }, { "id": "Teng-Alex-P", "name": { "family": "Teng", "given": "Alex P." } }, { "name": { "family": "Bennett", "given": "Ryan" } }, { "name": { "family": "Yang-Martin", "given": "Melissa" } }, { "name": { "family": "Shook", "given": "Michael A." } }, { "name": { "family": "Huey", "given": "Greg" } }, { "name": { "family": "Tanner", "given": "David" }, "orcid": "0000-0003-1940-4710" }, { "name": { "family": "Knote", "given": "Christoph" } }, { "name": { "family": "Kim", "given": "JongHo" } }, { "name": { "family": "Park", "given": "Rokjin" } }, { "name": { "family": "Brune", "given": "William" }, "orcid": "0000-0002-1609-4051" } ] }, "title": "Airborne formaldehyde and volatile organic compound measurements over the Daesan petrochemical complex on Korea's northwest coast during the Korea-United States Air Quality study", "ispublished": "pub", "full_text_status": "public", "keywords": "Mass balance VOC emissions, airborne formaldehyde and ethane measurements, VOC emissions over the Daesan petrochemical complex", "note": "\u00a9 2020 The Author(s). This is an open-access article distributed under the terms of the Creative Commons Attribution 4.0 International License (CC-BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. See http://creativecommons.org/licenses/by/4.0/. \n\nReceived: August 14 2020; Accepted: November 10 2020. \n\nWe acknowledge Andy Weinheimer and Denise Montzka of NCAR for their oxides of nitrogen measurements and the entire NASA DC-8 ground crew, aircraft crew, and pilots, which enabled the acquisition of in the situ aircraft data. The instrument team of P. Eichler, L. Kaser, and M. M\u00fcller as well as Ionicon Analytik is acknowledged for their support of this instrument in the field and during the mission preparation phase. \n\nFunding to the University of Colorado for AF and his group was supported by Grant Number NNX15AV02G from the NASA Tropospheric Chemistry Program. The KORUS-AQ mission was jointly funded by the NASA Tropospheric Chemistry Program and the Korean National Institute of Environmental Research (NIER). The PTR-ToF-MS measurements were supported by the Austrian Federal Ministry for Transport, Innovation and Technology (BMVIT) through the Austrian Space Applications Programme (ASAP) of the Austrian Research Promotion Agency (FFG). \n\nCompeting interests: The authors declare no competing interests. However, two of the authors, Isobel Simpson and Armin Wisthaler are Associate Editors of Elementa. \n\nAuthor contributions: \n\nAcquired and interpreted all the CAMS CH\u2082O and C\u2082H\u2086 data on the NASA DC-8 and wrote the manuscript: AF. \n\nResponsible for preparing the instrument for airborne measurements and helping in the data quality control, final data submission, and manuscript editing: JW, PW, DR. \n\nProvided significant critical input on the data analysis and interpretation: IJS (of the WAS team) and JHC (at NASA Langley). \n\nResponsible for the high quality WAS VOC measurement acquisition, follow-up laboratory analysis, data management, and final data quality control and submittal: The entire WAS team at Irvine, led by DRB, of IJS, NJB, SM, BB, and SCH. \n\nProvided DC-8 aircraft data and critical input on DC-8 measurements of wind speed and direction: JB at NASA Langley and RB, MY-M, and MAS at NSRC Bay Area Environmental Research Institute. \n\nAcquired HSRL data and provided critical input in the analysis of the mixed layer heights: JH and MF from the NASA Langley LIDAR group. \n\nProvided PTR-ToF-MS measurements of benzene and toluene: AW and TM at the Universities of Oslo and Innsbruck. \n\nProvided measurements of CO and CH4: G. Diskin and his group at NASA Langley. \n\nOversaw the KORUSv5 emission inventory and provided data for this article: JHW, MP, JK. \n\nProvided support in the analysis: JK at the Konkuk University and K-EM and SJ at the Gwangju Institute of Science and Technology. \n\nProvided measurements and analysis of alkene-hydroxynitrates employed in determining photochemically produced CH\u2082O: POW, MJK, JDC, and APT of the California Institute of Technology. \n\nProvided the FLEXPART back trajectories: CK of the Meteorological Institute in Germany. \n\nProvided critical measurements of SO\u2082: GH and DT at the GIT. \n\nProvided measurements of OH: WB at PSU. \n\nProvided critical supporting measurements: JHK at Hanseo University and RP at Seoul National University. \n\nRevised the manuscript and approved the submitted version for publication: All coauthors. \n\nData accessibility statement: All observational data from the KORUS-AQ mission, including the CAMS and WAS VOC data, are archived at http://doi.org/10.5067/Suborbital/KORUSAQ/DATA01.\n\nPublished - elementa.2020.121.pdf
Supplemental Material - supplemental_material_nov_2.pdf
", "abstract": "The U.S. National Aeronautics and Space Administration in partnership with Korea's National Institute of Environmental Research embarked on the Korea-United States Air Quality (KORUS-AQ) study to address air quality issues over the Korean peninsula. Underestimation of volatile organic compound (VOC) emissions from various large facilities on South Korea's northwest coast may contribute to this problem, and this study focuses on quantifying top-down emissions of formaldehyde (CH\u2082O) and VOCs from the largest of these facilities, the Daesan petrochemical complex, and comparisons with the latest emission inventories. To accomplish this and additional goals discussed herein, this study employed a number of measurements acquired during KORUS-AQ onboard the NASA DC-8 aircraft during three Daesan overflights on June 2, 3, and 5, 2016, in conjunction with a mass balance approach. The measurements included fast airborne measurements of CH\u2082O and ethane from an infrared spectrometer, additional fast measurements from other instruments, and a suite of 33 VOC measurements acquired by the whole air sampler. The mass balance approach resulted in consistent top-down yearly Daesan VOC emission flux estimates, which averaged (61 \u00b1 14) \u00d7 10\u00b3 MT/year for the 33 VOC compounds, a factor of 2.9 \u00b1 0.6 (\u00b11.0) higher than the bottom-up inventory value. The top-down Daesan emission estimate for CH\u2082O and its four primary precursors averaged a factor of 4.3 \u00b1 1.5 (\u00b1 1.9) times higher than the bottom-up inventory value. The uncertainty values in parentheses reflect upper limits for total uncertainty estimates. The resulting averaged top-down Daesan emission estimate for sulfur dioxide (SO\u2082) yielded a ratio of 0.81\u20131.0 times the bottom-up SO\u2082 inventory, and this provides an important cross-check on the accuracy of our mass balance analysis.", "date": "2020-12-31", "date_type": "published", "publication": "Elementa: Science of the Anthropocene", "volume": "8", "publisher": "University of California Press", "pagerange": "Art. No. 121", "id_number": "CaltechAUTHORS:20210301-074128123", "issn": "2325-1026", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210301-074128123", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NNX15AV02G" }, { "agency": "National Institute of Environmental Research (NIER)" }, { "agency": "Bundesministerium f\u00fcr Verkehr, Innovation und Technologie (BMVIT)" }, { "agency": "Austrian Research Promotion Agency (FFG)" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1525/elementa.2020.121", "primary_object": { "basename": "elementa.2020.121.pdf", "url": "https://authors.library.caltech.edu/records/cmrq4-fbg67/files/elementa.2020.121.pdf" }, "related_objects": [ { "basename": "supplemental_material_nov_2.pdf", "url": "https://authors.library.caltech.edu/records/cmrq4-fbg67/files/supplemental_material_nov_2.pdf" } ], "resource_type": "article", "pub_year": "2020", "author_list": "Fried, Alan; Walega, James; et el." }, { "id": "https://authors.library.caltech.edu/records/jp0wd-a0584", "eprint_id": 107029, "eprint_status": "archive", "datestamp": "2023-08-22 08:05:47", "lastmod": "2023-10-23 19:31:14", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Vasquez-Krystal-T", "name": { "family": "Vasquez", "given": "Krystal T." }, "orcid": "0000-0003-4540-4212" }, { "id": "Crounse-John-D", "name": { "family": "Crounse", "given": "John D." }, "orcid": "0000-0001-5443-729X" }, { "id": "Schulze-Benjamin-C", "name": { "family": "Schulze", "given": "Benjamin C." }, "orcid": "0000-0002-6405-8872" }, { "id": "Bates-Kelvin-H", "name": { "family": "Bates", "given": "Kelvin H." }, "orcid": "0000-0001-7544-9580" }, { "id": "Teng-Alexander-P", "name": { "family": "Teng", "given": "Alexander P." }, "orcid": "0000-0002-6434-0501" }, { "id": "Xu-Lu", "name": { "family": "Xu", "given": "Lu" }, "orcid": "0000-0002-0021-9876" }, { "id": "Allen-Hannah-M", "name": { "family": "Allen", "given": "Hannah M." }, "orcid": "0000-0002-4218-5133" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "Rapid hydrolysis of tertiary isoprene nitrate efficiently removes NO\u2093 from the atmosphere", "ispublished": "pub", "full_text_status": "public", "keywords": "atmospheric chemistry; isoprene; hydrolysis; organic nitrates; NOx", "note": "\u00a9 2020 Published under the PNAS license. \n\nEdited by Mark Thiemens, University of California San Diego, La Jolla, CA, and approved November 3, 2020 (received for review August 17, 2020). First published December 10, 2020. \n\nDevelopment of the GC-CIMS was supported by the NSF Major Research Instrumentation Program under Grant AGS-1428482 and the field and laboratory studies it participated in were supported by additional NSF funding (Grant AGS-1240604). We thank the Caltech campus and affiliated staff for accommodating our 2017 field study. Work performed by K.T.V. and H.M.A. was also supported by NSF through the Graduate Research Fellowship. \n\nAuthor contributions: J.D.C. and P.O.W. designed research; K.T.V., J.D.C., B.C.S., K.H.B., A.P.T., L.X., H.M.A., and P.O.W. performed research; J.D.C. and P.O.W. contributed new reagents/analytic tools; K.T.V., J.D.C., and A.P.T. analyzed data; and K.T.V., J.D.C., and P.O.W. wrote the paper. \n\nData Availability. Atmospheric trace gas measurements and model output data have been deposited in the California Institute of Technology Research Data Repository CaltechDATA. IHN isomer concentration data used here are available online (http://doi.org/10.22002/D1.971) along with the chromatograms collected at the field site (http://doi.org/10.22002/D1.1671), the output results of the 1-D atmospheric model (http://doi.org/10.22002/D1.1672), and the updated isoprene mechanism used in the global chemical transport model (http://doi.org/10.22002/D1.247). GEOS-Chem is available for public use at http://geos-chem.org/. \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.2017442117/-/DCSupplemental.\n\nPublished - 33011.full.pdf
Supplemental Material - pnas.2017442117.sapp.pdf
", "abstract": "The formation of a suite of isoprene-derived hydroxy nitrate (IHN) isomers during the OH-initiated oxidation of isoprene affects both the concentration and distribution of nitrogen oxide free radicals (NO\u2093). Experiments performed in an atmospheric simulation chamber suggest that the lifetime of the most abundant isomer, 1,2-IHN, is shortened significantly by a water-mediated process (leading to nitric acid formation), while the lifetime of a similar isomer, 4,3-IHN, is not. Consistent with these chamber studies, NMR kinetic experiments constrain the 1,2-IHN hydrolysis lifetime to less than 10 s in deuterium oxide (D\u2082O) at 298 K, whereas the 4,3-IHN isomer has been observed to hydrolyze much less efficiently. These laboratory findings are used to interpret observations of the IHN isomer distribution in ambient air. The IHN isomer ratio (1,2-IHN to 4,3-IHN) in a high NO\u2093 environment decreases rapidly in the afternoon, which is not explained using known gas-phase chemistry. When simulated with an observationally constrained model, we find that an additional loss process for the 1,2-IHN isomer with a time constant of about 6 h best explains our atmospheric measurements. Using estimates for 1,2-IHN Henry's law constant and atmospheric liquid water volume, we show that condensed-phase hydrolysis of 1,2-IHN can account for this loss process. Simulations from a global chemistry transport model show that the hydrolysis of 1,2-IHN accounts for a substantial fraction of NO\u2093 lost (and HNO\u2083 produced), resulting in large impacts on oxidant formation, especially over forested regions.", "date": "2020-12-29", "date_type": "published", "publication": "Proceedings of the National Academy of Sciences of the United States of America", "volume": "117", "number": "52", "publisher": "National Academy of Sciences", "pagerange": "33011-33016", "id_number": "CaltechAUTHORS:20201210-160240365", "issn": "0027-8424", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201210-160240365", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "AGS-1428482" }, { "agency": "NSF", "grant_number": "AGS-1240604" }, { "agency": "NSF Graduate Research Fellowship" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1073/pnas.2017442117", "pmcid": "PMC7777079", "primary_object": { "basename": "33011.full.pdf", "url": "https://authors.library.caltech.edu/records/jp0wd-a0584/files/33011.full.pdf" }, "related_objects": [ { "basename": "pnas.2017442117.sapp.pdf", "url": "https://authors.library.caltech.edu/records/jp0wd-a0584/files/pnas.2017442117.sapp.pdf" } ], "resource_type": "article", "pub_year": "2020", "author_list": "Vasquez, Krystal T.; Crounse, John D.; et el." }, { "id": "https://authors.library.caltech.edu/records/jvh7d-16y03", "eprint_id": 106816, "eprint_status": "archive", "datestamp": "2023-08-22 08:03:00", "lastmod": "2023-10-23 19:31:06", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Parker-Harrison-A", "name": { "family": "Parker", "given": "H. A." }, "orcid": "0000-0002-0041-2764" }, { "id": "Hasheminassab-Sina", "name": { "family": "Hasheminassab", "given": "S." }, "orcid": "0000-0002-4422-8547" }, { "id": "Crounse-John-D", "name": { "family": "Crounse", "given": "J. D." }, "orcid": "0000-0001-5443-729X" }, { "id": "Roehl-Coleen-M", "name": { "family": "Roehl", "given": "C. M." }, "orcid": "0000-0001-5383-8462" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "Impacts of Traffic Reductions Associated With COVID-19 on Southern California Air Quality", "ispublished": "pub", "full_text_status": "public", "keywords": "air quality; lockdown; COVID\u201019; South Coast Air Basin; ozone; nitrogen dioxide", "note": "\u00a9 2020 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\nIssue Online: 01 December 2020; Version of Record online: 01 December 2020; Accepted manuscript online: 23 November 2020; Manuscript accepted: 10 November 2020; Manuscript revised: 05 November 2020; Manuscript received: 01 August 2020. \n\nThe views expressed in this document are solely those of the authors and do not necessarily reflect those of the South Coast AQMD. The CITAQS facility was funded by Caltech's Linde Center for Global Environmental Science and the Resnick Sustainability Institute. We thank NASA via NNX17AE15G for support of retrievals of CH\u2082O from the Caltech TCCON station. Harrison Parker thanks the Rose Hill Foundation for initial support of his graduate fellowship. \n\nData Availability Statement: Data from the CITAQS are available by request and will be available online to the public in the near future. All data from the AQMD sites are available through the California Air Resources Board Air Quality Data Query Tool (https://www.arb.ca.gov/aqmis2/aqdselect.php). Data from the CalNex campaign are available online (https://www.esrl.noaa.gov/csl/projects/calnex/). TROPOMI data used in this research are available through the Sentinel\u20105P Data Hub (https://s5phub.copernicus.eu/). Traffic data used here are available through the Caltrans PeMS program (https://pems.dot.ca.gov/). Weather data are available online or by contacting the corresponding author (https://tccon\u2010weather.caltech.edu/).\n\nPublished - 2020GL090164.pdf
Supplemental Material - grl61597-sup-0001-2020gl090164-si-s01.pdf
", "abstract": "On 19 March 2020, California put in place Stay\u2010At\u2010Home orders to reduce the spread of SARS\u2010CoV\u20102. As a result, decreases up to 50% in traffic occurred across the South Coast Air Basin (SoCAB). We report that, compared to the 19 March to 30 June period of the last 5\u2009years, the 2020 concentrations of PM_(2.5) and NO_x showed an overall reduction across the basin. O\u2083 concentrations decreased in the western part of the basin and generally increased in the downwind areas. The NO_x decline in 2020 (approximately 27% basin\u2010wide) is in addition to ongoing declines over the last two decades (on average 4% less than the \u22126.8% per year afternoon NO\u2082 concentration decrease) and provides insight into how air quality may respond over the next few years of continued vehicular reductions. The modest changes in O\u2083 suggests additional mitigation will be necessary to comply with air quality standards.", "date": "2020-12-16", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "47", "number": "23", "publisher": "American Geophysical Union", "pagerange": "Art. No. e2020GL090164", "id_number": "CaltechAUTHORS:20201124-133212486", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201124-133212486", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Ronald And Maxine Linde Center for Global Environmental Science" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "NASA", "grant_number": "NNX17AE15G" }, { "agency": "Rose Hills Foundation" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "COVID-19" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2020gl090164", "pmcid": "PMC7744837", "primary_object": { "basename": "2020GL090164.pdf", "url": "https://authors.library.caltech.edu/records/jvh7d-16y03/files/2020GL090164.pdf" }, "related_objects": [ { "basename": "grl61597-sup-0001-2020gl090164-si-s01.pdf", "url": "https://authors.library.caltech.edu/records/jvh7d-16y03/files/grl61597-sup-0001-2020gl090164-si-s01.pdf" } ], "resource_type": "article", "pub_year": "2020", "author_list": "Parker, H. A.; Hasheminassab, S.; et el." }, { "id": "https://authors.library.caltech.edu/records/wfv21-h5r97", "eprint_id": 107086, "eprint_status": "archive", "datestamp": "2023-08-22 08:02:14", "lastmod": "2023-10-23 15:30:48", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Taylor-Thoas-E", "name": { "family": "Taylor", "given": "Thomas E." }, "orcid": "0000-0002-1650-4882" }, { "id": "Eldering-Annmarie", "name": { "family": "Eldering", "given": "Annmarie" }, "orcid": "0000-0003-1080-9922" }, { "id": "Merrelli-Aronne", "name": { "family": "Merrelli", "given": "Aronne" } }, { "id": "Kiel-Matth\u00e4us", "name": { "family": "Kiel", "given": "Matth\u00e4us" }, "orcid": "0000-0002-9784-962X" }, { "id": "Somkuti-Peter", "name": { "family": "Somkuti", "given": "Peter" }, "orcid": "0000-0002-5858-8471" }, { "id": "Cheng-Cecilia", "name": { "family": "Cheng", "given": "Cecilia" } }, { "id": "Rosenberg-Robert", "name": { "family": "Rosenberg", "given": "Robert" }, "orcid": "0000-0002-0459-4630" }, { "id": "Fisher-Brendan-M", "name": { "family": "Fisher", "given": "Brendan" } }, { "id": "Crisp-David", "name": { "family": "Crisp", "given": "David" }, "orcid": "0000-0002-4573-9998" }, { "id": "Basilio-Ralph", "name": { "family": "Basilio", "given": "Ralph" } }, { "id": "Bennett-Matthew", "name": { "family": "Bennett", "given": "Matthew" } }, { "id": "Cervantes-Daniel", "name": { "family": "Cervantes", "given": "Daniel" } }, { "id": "Chang-Albert-Y", "name": { "family": "Chang", "given": "Albert" } }, { "id": "Dang-Lan", "name": { "family": "Dang", "given": "Lan" } }, { "id": "Frankenberg-C", "name": { "family": "Frankenberg", "given": "Christian" }, "orcid": "0000-0002-0546-5857" }, { "id": "Haemmerle-Vance-R", "name": { "family": "Haemmerle", "given": "Vance R." } }, { "id": "Keller-Graziela-R", "name": { "family": "Keller", "given": "Graziela R." } }, { "id": "Kurosu-Thomas-P", "name": { "family": "Kurosu", "given": "Thomas" } }, { "id": "Laughner-Joshua-L", "name": { "family": "Laughner", "given": "Joshua L." }, "orcid": "0000-0002-8599-4555" }, { "id": "Lee-Richard-A-M", "name": { "family": "Lee", "given": "Richard" }, "orcid": "0000-0001-6509-697X" }, { "id": "Marchetti-Yuliya", "name": { "family": "Marchetti", "given": "Yuliya" } }, { "id": "Nelson-Robert-R", "name": { "family": "Nelson", "given": "Robert R." }, "orcid": "0000-0002-3471-5683" }, { "id": "O'Dell-Christopher-W", "name": { "family": "O'Dell", "given": "Christopher W." } }, { "id": "Osterman-Gregory", "name": { "family": "Osterman", "given": "Gregory" } }, { "id": "Pavlick-Ryan", "name": { "family": "Pavlick", "given": "Ryan" } }, { "id": "Roehl-Coleen-M", "name": { "family": "Roehl", "given": "Coleen" }, "orcid": "0000-0001-5383-8462" }, { "id": "Schneider-Robert", "name": { "family": "Schneider", "given": "Robert" } }, { "id": "Spiers-Gary-D", "name": { "family": "Spiers", "given": "Gary" } }, { "id": "To-Cathy", "name": { "family": "To", "given": "Cathy" } }, { "id": "Wells-Christopher", "name": { "family": "Wells", "given": "Christopher" } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Yelamanchili-Amruta", "name": { "family": "Yelamanchili", "given": "Amruta" } }, { "id": "Yu-Shanshan", "name": { "family": "Yu", "given": "Shanshan" } } ] }, "title": "OCO-3 early mission operations and initial (vEarly) XCO\u2082 and SIF retrievals", "ispublished": "pub", "full_text_status": "public", "keywords": "OCO-3; OCO-2; ISS; Greenhouse gases; Carbon dioxide; Solar-induced chlorophyll fluorescence; Calibration", "note": "\u00a9 2020 The Author(s). Published by Elsevier Inc. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/). \n\nReceived 6 June 2020, Revised 22 July 2020, Accepted 4 August 2020, Available online 1 September 2020. \n\nPart of the 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 [prime contract number 80NM0018D0004]. The CSU contribution to this work was supported by JPL subcontract 1439002. The University of Wisconsin/SSEC contribution to this work was supported by JPL subcontract 1577173. \n\nWe declare no conflicts of interest with this research.\n\nPublished - 1-s2.0-S0034425720304028-main.pdf
", "abstract": "NASA's Orbiting Carbon Observatory-3 (OCO-3) was installed on the International Space Station (ISS) on 10 May 2019. OCO-3 combines the flight spare spectrometer from the Orbiting Carbon Observatory-2 (OCO-2) mission, which has been in operation since 2014, with a new Pointing Mirror Assembly (PMA) that facilitates observations of non-nadir targets from the nadir-oriented ISS platform. The PMA is a new feature of OCO-3, which is being used to collect data in all science modes, including nadir (ND), sun-glint (GL), target (TG), and the new snapshot area mapping (SAM) mode.\nThis work provides an initial assessment of the OCO-3 instrument and algorithm performance, highlighting results from the first 8 months of operations spanning August 2019 through March 2020. During the In-Orbit Checkout (IOC) phase, critical systems such as power and cooling were verified, after which the OCO-3 spectrometer and PMA were subjected to a series of rigorous tests. First light of the OCO-3 spectrometer was on 26 June 2019, with full science operations beginning on 6 August 2019. The OCO-3 spectrometer on-orbit performance is consistent with that seen during preflight testing. Signal to noise ratios are in the expected range needed for high quality retrievals of the column-averaged carbon dioxide (CO\u2082) dry-air mole fraction (XCO\u2082) and solar-induced chlorophyll fluorescence (SIF), which will be used to help quantify and constrain the global carbon cycle. \n\nThe first public release of OCO-3 Level 2 (L2) data products, called \"vEarly\", is being distributed by NASA's Goddard Earth Sciences Data and Information Services Center (GES DISC). The intent of the vEarly product is to evaluate early mission performance, facilitate comparisons with OCO-2 products, and identify key areas to improve for the next data release. The vEarly XCO2 exhibits a root-mean-squared-error (RMSE) of \u2243 1, 1, 2 ppm versus a truth proxy for nadir-land, TG&SAM, and glint-water observations, respectively. The vEarly SIF shows a correlation with OCO-2 measurements of >0.9 for highly coincident soundings. Overall, the Level 2 SIF and XCO\u2082 products look very promising, with performance comparable to OCO-2. A follow-on version of the OCO-3 L2 product containing a number of refinements, e.g., instrument calibration, pointing accuracy, and retrieval algorithm tuning, is anticipated by early in 2021.", "date": "2020-12-15", "date_type": "published", "publication": "Remote Sensing of Environment", "volume": "251", "publisher": "Elsevier", "pagerange": "Art. No. 112032", "id_number": "CaltechAUTHORS:20201215-120535761", "issn": "0034-4257", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201215-120535761", "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": "JPL", "grant_number": "1439002" }, { "agency": "JPL", "grant_number": "1577173" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/j.rse.2020.112032", "primary_object": { "basename": "1-s2.0-S0034425720304028-main.pdf", "url": "https://authors.library.caltech.edu/records/wfv21-h5r97/files/1-s2.0-S0034425720304028-main.pdf" }, "resource_type": "article", "pub_year": "2020", "author_list": "Taylor, Thomas E.; Eldering, Annmarie; et el." }, { "id": "https://authors.library.caltech.edu/records/7ek82-77222", "eprint_id": 107659, "eprint_status": "archive", "datestamp": "2023-08-22 08:00:49", "lastmod": "2023-10-23 19:30:31", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Parker-Robert-J", "name": { "family": "Parker", "given": "Robert J." }, "orcid": "0000-0002-0801-0831" }, { "name": { "family": "Webb", "given": "Alex" }, "orcid": "0000-0002-7164-7835" }, { "name": { "family": "Boesch", "given": "Hartmut" }, "orcid": "0000-0003-3944-9879" }, { "name": { "family": "Somkuti", "given": "Peter" }, "orcid": "0000-0002-5858-8471" }, { "name": { "family": "Barrio Guillo", "given": "Rocio" } }, { "name": { "family": "Di Noia", "given": "Antonio" }, "orcid": "0000-0002-5052-0763" }, { "name": { "family": "Kalaitzi", "given": "Nikoleta" } }, { "name": { "family": "Anand", "given": "Jasdeep S." } }, { "name": { "family": "Bergamaschi", "given": "Peter" }, "orcid": "0000-0003-4555-1829" }, { "name": { "family": "Chevallier", "given": "Frederic" }, "orcid": "0000-0002-4327-3813" }, { "name": { "family": "Palmer", "given": "Paul I." }, "orcid": "0000-0002-1487-0969" }, { "name": { "family": "Feng", "given": "Liang" } }, { "name": { "family": "Deutscher", "given": "Nicholas M." }, "orcid": "0000-0002-2906-2577" }, { "name": { "family": "Feist", "given": "Dietrich G." }, "orcid": "0000-0002-5890-6687" }, { "name": { "family": "Griffith", "given": "David W. T." }, "orcid": "0000-0002-7986-1924" }, { "name": { "family": "Hase", "given": "Frank" } }, { "name": { "family": "Kivi", "given": "Rigel" }, "orcid": "0000-0001-8828-2759" }, { "name": { "family": "Morino", "given": "Isamu" }, "orcid": "0000-0003-2720-1569" }, { "name": { "family": "Notholt", "given": "Justus" } }, { "name": { "family": "Oh", "given": "Young-Suk" }, "orcid": "0000-0001-8010-1597" }, { "name": { "family": "Ohyama", "given": "Hirofumi" }, "orcid": "0000-0003-2109-9874" }, { "name": { "family": "Petri", "given": "Christof" }, "orcid": "0000-0002-7010-5532" }, { "name": { "family": "Pollard", "given": "David F." }, "orcid": "0000-0001-9923-2984" }, { "id": "Roehl-Coleen-M", "name": { "family": "Roehl", "given": "Coleen" }, "orcid": "0000-0001-5383-8462" }, { "name": { "family": "Sha", "given": "Mahesh K." }, "orcid": "0000-0003-1440-1529" }, { "name": { "family": "Shiomi", "given": "Kei" } }, { "name": { "family": "Strong", "given": "Kimberly" }, "orcid": "0000-0001-9947-1053" }, { "name": { "family": "Sussmann", "given": "Ralf" } }, { "name": { "family": "T\u00e9", "given": "Yao" }, "orcid": "0000-0001-6405-8074" }, { "name": { "family": "Velazco", "given": "Voltaire A." }, "orcid": "0000-0002-1376-438X" }, { "name": { "family": "Warneke", "given": "Thorsten" }, "orcid": "0000-0001-5185-3415" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" }, { "name": { "family": "Wunch", "given": "Debra" }, "orcid": "0000-0002-4924-0377" } ] }, "title": "A decade of GOSAT Proxy satellite CH\u2084 observations", "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: 07 May 2020 \u2013 Discussion started: 03 Jul 2020 \u2013 Revised: 21 Oct 2020 \u2013 Accepted: 26 Oct 2020 \u2013 Published: 14 Dec 2020. \n\nRobert J. Parker, Hartmut Boesch, Alex Webb, Paul I. Palmer and Liang Feng are funded via the UK National Centre for Earth Observation (NE/R016518/1 and NE/N018079/1). Rocio Barrio Guillo and Nikoleta Kalaitzi were funded by a Leicester Institute for Space and EO (LISEO) and ESA-Dragon Programme studentship respectively. JSA was funded by an ESA Living Planet Fellowship. We acknowledge funding from the ESA GHG-CCI and Copernicus C3S projects. We thank the Japanese Aerospace Exploration Agency, National Institute for Environmental Studies and the Ministry of Environment for the GOSAT data and their continuous support as part of the Joint Research Agreement. This research used the ALICE High Performance Computing Facility at the University of Leicester for the GOSAT retrievals and analysis. The TM5-4DVAR CH\u2084 inversions have been supported by ECMWF providing computing resources under the special project \"Improve European and global CH\u2084 and N\u2082O flux inversions (2018\u20132020)\". \n\nTCCON gratefully acknowledges financial support by ESA within the S5P validation programme. Stations at Park Falls, Lamont and Darwin are supported by NASA. Stations at Tsukuba, Rikubetsu and Burgos are supported in part by the GOSAT series project. Burgos is supported in part by the Energy Development Corp. Philippines. Ascension Island and Garmisch stations have been supported by the European Space Agency (ESA) under grant 4000120088/17/I-EF and by the German Bundesministerium f\u00fcr Wirtschaft und Energie (BMWi) under grants 50EE1711C, 50EE1711E and 50EE1711D. We thank the ESA Ariane Tracking Station at North East Bay, Ascension Island, for hosting and local support. The ETL station is funded by CFI/ORF, NSERC, ECCC and the CSA. The Paris station has received funding from Sorbonne Universit\u00e9, the French research center CNRS, the French space agency CNES and R\u00e9gion \u00cele-de-France. The Eureka measurements were made at the Polar Environment Atmospheric Research Laboratory (PEARL) by the Canadian Network for the Detection of Atmospheric Change (CANDAC), primarily supported by the Natural Sciences and Engineering Research Council of Canada, Environment and Climate Change Canada, and the Canadian Space Agency. The Anmyeondo station has received funding from the Korea Meteorological Administration Research and Development Program \"Development and Assessment of IPCC AR6 Climate Change Scenario\" under grant 1365003000. The R\u00e9union station is operated by the Royal Belgian Institute for Space Aeronomy with financial support in 2014, 2015, 2016, 2017, 2018 and 2019 under the EU project ICOS-Inwire and the ministerial decree for ICOS (FR/35/IC4) and local activities supported by LACy/UMR8105 \u2013 Universit\u00e9 de La R\u00e9union. TCCON measurements in Australia are supported by NASA grants NAG5-12247 and NNH05-GD07G, Australian Research Council grants LE0668470, DP089468, DP110103118, DP140101552, DP160101598 and FT180100327, and the GOSAT series project. \n\nThis research has been supported by the NERC National Centre for Earth Observation (grant nos. NE/N018079/1 and NE/R016518/1). \n\nAuthor contributions. RJP developed and produced the Proxy XCH4 data, performed the analysis, and wrote the manuscript. AW assisted in the production of the data. AW, PS, ADN, HB, JSA, RBG and NK all contributed to development and analysis at different stages of the processing chain. All authors contributed towards discussion and interpretation of the analysis. PB, FC, PIP and LF provided model data and contributed to the interpretation of the comparisons. All TCCON co-authors provided TCCON data and contributed towards interpretation of the GOSAT\u2013TCCON comparisons. \n\nData availability. The University of Leicester GOSAT Proxy v9.0 XCH4 data are available from the Centre for Environmental Data Analysis data repository at https://doi.org/10.5285/18ef8247f52a4cb6a14013f8235cc1eb (Parker and Boesch, 2020). The TCCON data are available from the TCCON Data Archive at https://tccondata.org (TCCON Data Archive, 2020; individual data citations are provided in Table F1). CAMS model CO2 (v18r2) data is available from the Copernicus Atmospheric Data Store at https://ads.atmosphere.copernicus.eu/cdsapp#!/dataset/cams-global-greenhouse-gas-inversion (ECMWF, 2020a). MACC model CH4 (v10-S1NOAA) is available from ECMWF at https://apps.ecmwf.int/datasets/data/macc-ghg-inversions/ (ECMWF, 2020b). NOAA CarbonTracker model CO2 (CT2017 and CT2019-NRT) are available from NOAA ESRL, Boulder, Colorado, USA, at ftp://aftp.cmdl.noaa.gov/products/carbontracker/co2/ (NOAA, 2020). \n\nThe authors declare that they have no conflict of interest. \n\nReview statement. This paper was edited by David Carlson and reviewed by three anonymous referees.\n\nPublished - essd-12-3383-2020.pdf
", "abstract": "This work presents the latest release (v9.0) of the University of Leicester GOSAT Proxy XCH\u2084 dataset. Since the launch of the GOSAT satellite in 2009, these data have been produced by the UK National Centre for Earth Observation (NCEO) as part of the ESA Greenhouse Gas Climate Change Initiative (GHG-CCI) and Copernicus Climate Change Services (C3S) projects. With now over a decade of observations, we outline the many scientific studies achieved using past versions of these data in order to highlight how this latest version may be used in the future. \n\nWe describe in detail how the data are generated, providing information and statistics for the entire processing chain from the L1B spectral data through to the final quality-filtered column-averaged dry-air mole fraction (XCH\u2084) data. We show that out of the 19.5 million observations made between April 2009 and December 2019, we determine that 7.3 million of these are sufficiently cloud-free (37.6\u2009%) to process further and ultimately obtain 4.6 million (23.5\u2009%) high-quality XCH\u2084 observations. We separate these totals by observation mode (land and ocean sun glint) and by month, to provide data users with the expected data coverage, including highlighting periods with reduced observations due to instrumental issues. \n\nWe perform extensive validation of the data against the Total Carbon Column Observing Network (TCCON), comparing to ground-based observations at 22 locations worldwide. We find excellent agreement with TCCON, with an overall correlation coefficient of 0.92 for the 88\u2009345 co-located measurements. The single-measurement precision is found to be 13.72\u2009ppb, and an overall global bias of 9.06\u2009ppb is determined and removed from the Proxy XCH\u2084 data. Additionally, we validate the separate components of the Proxy (namely the modelled XCO\u2082 and the XCH\u2084\u2215XCO\u2082 ratio) and find these to be in excellent agreement with TCCON. \n\nIn order to show the utility of the data for future studies, we compare against simulated XCH\u2084 from the TM5 model. We find a high degree of consistency between the model and observations throughout both space and time. When focusing on specific regions, we find average differences ranging from just 3.9 to 15.4\u2009ppb. We find the phase and magnitude of the seasonal cycle to be in excellent agreement, with an average correlation coefficient of 0.93 and a mean seasonal cycle amplitude difference across all regions of \u22120.84\u2009ppb. \n\nThese data are available at https://doi.org/10.5285/18ef8247f52a4cb6a14013f8235cc1eb (Parker and Boesch, 2020).", "date": "2020-12-14", "date_type": "published", "publication": "Earth System Science Data", "volume": "12", "number": "4", "publisher": "European Geophysical Society", "pagerange": "3383-3412", "id_number": "CaltechAUTHORS:20210122-092204711", "issn": "1866-3516", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210122-092204711", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Natural Environment Research Council (NERC)", "grant_number": "NE/R016518/1" }, { "agency": "Natural Environment Research Council (NERC)", "grant_number": "NE/N018079/1" }, { "agency": "Leicester Institute for Space and EO" }, { "agency": "European Space Agency (ESA)", "grant_number": "4000120088/17/I-EF" }, { "agency": "Japan Aerospace Exploration Agency (JAXA)" }, { "agency": "National Institute for Environmental Studies (Japan)" }, { "agency": "Ministry of Environment (Japan)" }, { "agency": "European Centre for Medium-Range Weather Forecasts (ECMWF)" }, { "agency": "Energy Development Corp." }, { "agency": "Bundesministerium f\u00fcr Wirtschaft und Energie (BMWi)", "grant_number": "50EE1711C" }, { "agency": "Bundesministerium f\u00fcr Wirtschaft und Energie (BMWi)", "grant_number": "50EE1711E" }, { "agency": "Bundesministerium f\u00fcr Wirtschaft und Energie (BMWi)", "grant_number": "50EE1711D" }, { "agency": "Canada Foundation for Innovation" }, { "agency": "Natural Sciences and Engineering Research Council of Canada (NSERC)" }, { "agency": "Ontario Research Fund" }, { "agency": "Environment and Climate Change Canada" }, { "agency": "Canadian Space Agency (CSA)" }, { "agency": "Sorbonne Universit\u00e9" }, { "agency": "Centre National de la Recherche Scientifique (CNRS)" }, { "agency": "Centre National d'\u00c9tudes Spatiales (CNES)" }, { "agency": "R\u00e9gion \u00cele-de-France" }, { "agency": "Korea Meteorological Administration", "grant_number": "1365003000" }, { "agency": "Royal Belgian Institute for Space Aeronomy" }, { "agency": "European Research Council (ERC)" }, { "agency": "ICOS Belgium", "grant_number": "FR/35/IC4" }, { "agency": "Universit\u00e9 de La R\u00e9union", "grant_number": "LACy/UMR8105" }, { "agency": "NASA", "grant_number": "NAG5-12247" }, { "agency": "NASA", "grant_number": "NNH05-GD07G" }, { "agency": "Australian Research Council", "grant_number": "LE0668470" }, { "agency": "Australian Research Council", "grant_number": "DP089468" }, { "agency": "Australian Research Council", "grant_number": "DP110103118" }, { "agency": "Australian Research Council", "grant_number": "DP140101552" }, { "agency": "Australian Research Council", "grant_number": "DP160101598" }, { "agency": "Australian Research Council", "grant_number": "FT180100327" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/essd-12-3383-2020", "primary_object": { "basename": "essd-12-3383-2020.pdf", "url": "https://authors.library.caltech.edu/records/7ek82-77222/files/essd-12-3383-2020.pdf" }, "resource_type": "article", "pub_year": "2020", "author_list": "Parker, Robert J.; Webb, Alex; et el." }, { "id": "https://authors.library.caltech.edu/records/wfdv4-22r18", "eprint_id": 107503, "eprint_status": "archive", "datestamp": "2023-08-20 00:45:56", "lastmod": "2023-10-20 23:01:10", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Gaubert-Benjamin", "name": { "family": "Gaubert", "given": "Benjamin" }, "orcid": "0000-0002-6595-0686" }, { "id": "Emmons-Louisa-K", "name": { "family": "Emmons", "given": "Louisa K." }, "orcid": "0000-0003-2325-6212" }, { "id": "Raeder-Kevin", "name": { "family": "Raeder", "given": "Kevin" } }, { "id": "Tilmes-Simone", "name": { "family": "Tilmes", "given": "Simone" }, "orcid": "0000-0002-6557-3569" }, { "id": "Miyazaki-Kazuyuki", "name": { "family": "Miyazaki", "given": "Kazuyuki" }, "orcid": "0000-0002-1466-4655" }, { "id": "Arellano-Avelino-F-Jr", "name": { "family": "Arellano", "given": "Avelino F., Jr." }, "orcid": "0000-0002-2615-5831" }, { "id": "Elguindi-Nellie", "name": { "family": "Elguindi", "given": "Nellie" }, "orcid": "0000-0002-9211-4173" }, { "id": "Granier-Claire", "name": { "family": "Granier", "given": "Claire" }, "orcid": "0000-0002-3777-6078" }, { "id": "Tang-Wenfu", "name": { "family": "Tang", "given": "Wenfu" }, "orcid": "0000-0002-0107-4496" }, { "id": "Barr\u00e9-J\u00e9r\u00f4me", "name": { "family": "Barr\u00e9", "given": "J\u00e9r\u00f4me" } }, { "id": "Worden-Helen-M", "name": { "family": "Worden", "given": "Helen M." }, "orcid": "0000-0002-5949-9307" }, { "id": "Buchholz-Rebecca-R", "name": { "family": "Buchholz", "given": "Rebecca R." }, "orcid": "0000-0001-8124-2455" }, { "id": "Edwards-David-P", "name": { "family": "Edwards", "given": "David P." }, "orcid": "0000-0003-4342-1190" }, { "id": "Franke-Philipp", "name": { "family": "Franke", "given": "Philipp" }, "orcid": "0000-0001-6298-164X" }, { "id": "Anderson-Jeffrey-L", "name": { "family": "Anderson", "given": "Jeffrey L." } }, { "id": "Saunois-Marielle", "name": { "family": "Saunois", "given": "Marielle" }, "orcid": "0000-0003-3983-2931" }, { "id": "Schroeder-Jason-R", "name": { "family": "Schroeder", "given": "Jason R." } }, { "id": "Woo-Jung-Hun", "name": { "family": "Woo", "given": "Jung-Hun" } }, { "id": "Simpson-Isobel-J", "name": { "family": "Simpson", "given": "Isobel J." }, "orcid": "0000-0002-4211-1126" }, { "id": "Blake-Donald-R", "name": { "family": "Blake", "given": "Donald R." }, "orcid": "0000-0002-8283-5014" }, { "id": "Meinardi-Simone", "name": { "family": "Meinardi", "given": "Simone" }, "orcid": "0000-0003-4828-9889" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Crounse-John-D", "name": { "family": "Crounse", "given": "John" }, "orcid": "0000-0001-5443-729X" }, { "id": "Teng-Alexander-P", "name": { "family": "Teng", "given": "Alex" }, "orcid": "0000-0002-6434-0501" }, { "id": "Kim-Michelle-J", "name": { "family": "Kim", "given": "Michelle" }, "orcid": "0000-0002-4922-4334" }, { "id": "Dickerson-Russell-R", "name": { "family": "Dickerson", "given": "Russell R." }, "orcid": "0000-0003-0206-3083" }, { "id": "He-Hao", "name": { "family": "He", "given": "Hao" }, "orcid": "0000-0002-6823-9603" }, { "id": "Ren-Xinrong", "name": { "family": "Ren", "given": "Xinrong" }, "orcid": "0000-0001-9974-1666" }, { "id": "Pusede-Sally-E", "name": { "family": "Pusede", "given": "Sally E." }, "orcid": "0000-0002-3041-0209" }, { "id": "Diskin-Glenn-S", "name": { "family": "Diskin", "given": "Glenn S." }, "orcid": "0000-0002-3617-0269" } ] }, "title": "Correcting model biases of CO in East Asia: impact on oxidant distributions during KORUS-AQ", "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: 15 Jun 2020 \u2013 Discussion started: 30 Jun 2020 \u2013 Revised: 19 Oct 2020 \u2013 Accepted: 19 Oct 2020 \u2013 Published: 01 Dec 2020. \n\nWe thank the editor Tim Butler and two anonymous reviewers for the constructive comments and useful suggestions. 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. Neither the European Commission nor ECMWF is responsible for any use that may be made of the information it contains. We thank Yi Yin, Arjo Segers, Aki Tsuruta, Peter Bergamaschi, and Bo Zheng for sharing their CH4 inversions. We acknowledge James H. Crawford, Alan Fried, Andrew Weinheimer, and everybody that contributed to the KORUS-AQ campaign. The PTR-MS instrument team (Philipp Eichler, Lisa Kaser, Toms Mikoviny, Markus M\u00fcller, Armin Wisthaler) is acknowledged for providing the PTR-MS data for this study. We also thank Duseong Jo for reading the paper. \n\nThis research has been supported by the National Aeronautics and Space Administration (grant no. NNX16AD96G) and the National Oceanic and Atmospheric Administration (grant no. NA18OAR4310283). \n\nAuthor contributions. BG and LE designed the study. BG performed all the simulations with help from LE, ST, KR and JB. BG and LE analyzed the results with contributions from all authors. BG, LE, and AFA wrote the original draft. All authors participated in paper review, comments, and editing. \n\nCode and data availability. CESM2.1.0 is a publicly released version of the Community Earth System Model that is freely available online (at https://www.cesm.ucar.edu/, last access: 2 April 2020). The Data Assimilation Research Testbed is open-source software (version Manhattan; Boulder, Colorado: UCAR/NCAR/CISL/DAReS, https://doi.org/10.5065/D6WQ0202); code and documentation are available at https://dart.ucar.edu/ (last access: 22 November 2020). \n\nThe Korea\u2013United States Air Quality Field Study (KORUS-AQ) dataset is available at https://doi.org/10.5067/Suborbital/KORUSAQ/DATA01. \n\nThe ARIAs observational dataset is available at https://www-air.larc.nasa.gov/cgi-bin/ArcView/korusaq?OTHER=1#top (last access: 24 November 2020). \n\nMOPITT data are available at https://www2.acom.ucar.edu/mopitt (last access: 24 November 2020, UCAR, 2020). \n\nThe Tropospheric Chemistry Reanalysis version 2 is available for download at https://tes.jpl.nasa.gov/chemical-reanalysis/products/monthly-mean/ (last access: 24 November 2020, JPL, 2020). \n\nThe Copernicus Atmosphere Monitoring Service (CAMS) global bottom-up emission inventory is available on the Emissions of atmospheric Compounds and Compilation of Ancillary Data (ECCAD) website (https://eccad3.sedoo.fr, last access: 24 November 2020, AERIS, 2020). \n\nSupplement. The supplement related to this article is available online at: https://doi.org/10.5194/acp-20-14617-2020-supplement. \n\nThe authors declare that they have no conflict of interest. \n\nReview statement. This paper was edited by Tim Butler and reviewed by two anonymous referees.\n\nPublished - acp-20-14617-2020.pdf
", "abstract": "Global coupled chemistry\u2013climate models underestimate carbon monoxide (CO) in the Northern Hemisphere, exhibiting a pervasive negative bias against measurements peaking in late winter and early spring. While this bias has been commonly attributed to underestimation of direct anthropogenic and biomass burning emissions, chemical production and loss via OH reaction from emissions of anthropogenic and biogenic volatile organic compounds (VOCs) play an important role. Here we investigate the reasons for this underestimation using aircraft measurements taken in May and June 2016 from the Korea\u2013United States Air Quality (KORUS-AQ) experiment in South Korea and the Air Chemistry Research in Asia (ARIAs) in the North China Plain (NCP). For reference, multispectral CO retrievals (V8J) from the Measurements of Pollution in the Troposphere (MOPITT) are jointly assimilated with meteorological observations using an ensemble adjustment Kalman filter (EAKF) within the global Community Atmosphere Model with Chemistry (CAM-Chem) and the Data Assimilation Research Testbed (DART). With regard to KORUS-AQ data, CO is underestimated by 42\u2009% in the control run and by 12\u2009% with the MOPITT assimilation run. The inversion suggests an underestimation of anthropogenic CO sources in many regions, by up to 80\u2009% for northern China, with large increments over the Liaoning Province and the North China Plain (NCP). Yet, an often-overlooked aspect of these inversions is that correcting the underestimation in anthropogenic CO emissions also improves the comparison with observational O\u2083 datasets and observationally constrained box model simulations of OH and HO\u2082. Running a CAM-Chem simulation with the updated emissions of anthropogenic CO reduces the bias by 29\u2009% for CO, 18\u2009% for ozone, 11\u2009% for HO\u2082, and 27\u2009% for OH. Longer-lived anthropogenic VOCs whose model errors are correlated with CO are also improved, while short-lived VOCs, including formaldehyde, are difficult to constrain solely by assimilating satellite retrievals of CO. During an anticyclonic episode, better simulation of O\u2083, with an average underestimation of 5.5\u2009ppbv, and a reduction in the bias of surface formaldehyde and oxygenated VOCs can be achieved by separately increasing by a factor of 2 the modeled biogenic emissions for the plant functional types found in Korea. Results also suggest that controlling VOC and CO emissions, in addition to widespread NO_x controls, can improve ozone pollution over East Asia.", "date": "2020-12-01", "date_type": "published", "publication": "Atmospheric Chemistry and Physics", "volume": "20", "number": "23", "publisher": "European Geosciences Union", "pagerange": "14617-14647", "id_number": "CaltechAUTHORS:20210114-164620773", "issn": "1680-7324", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210114-164620773", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NNX16AD96G" }, { "agency": "National Oceanic and Atmospheric Administration (NOAA)", "grant_number": "NA18OAR4310283" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/acp-20-14617-2020", "pmcid": "PMC7786812", "primary_object": { "basename": "acp-20-14617-2020.pdf", "url": "https://authors.library.caltech.edu/records/wfdv4-22r18/files/acp-20-14617-2020.pdf" }, "resource_type": "article", "pub_year": "2020", "author_list": "Gaubert, Benjamin; Emmons, Louisa K.; et el." }, { "id": "https://authors.library.caltech.edu/records/0kptp-jnp85", "eprint_id": 106815, "eprint_status": "archive", "datestamp": "2023-08-22 07:48:49", "lastmod": "2023-10-20 23:49:46", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Liu-Junjie", "name": { "family": "Liu", "given": "Junjie" }, "orcid": "0000-0002-7184-6594" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Parazoo-Nicholas-C", "name": { "family": "Parazoo", "given": "Nicholas C." }, "orcid": "0000-0002-4424-7780" }, { "id": "Yin-Yi", "name": { "family": "Yin", "given": "Yi" }, "orcid": "0000-0003-4750-4997" }, { "id": "Frankenberg-C", "name": { "family": "Frankenberg", "given": "Christian" }, "orcid": "0000-0002-0546-5857" } ] }, "title": "Observational Constraints on the Response of High\u2010Latitude Northern Forests to Warming", "ispublished": "pub", "full_text_status": "public", "keywords": "OCO\u20102; SIF; GPP", "note": "\u00a9 2020 Jet Propulsion Laboratory. 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: 24 November 2020; Version of Record online: 24 November 2020; Manuscript accepted: 19 October 2020; Manuscript revised: 12 October 2020; Manuscript received: 01 June 2020. \n\nWe thank Editor Eric Davidson, reviewer Shilong Piao, and two other anonymous reviewers for their constructive comments. We also thank James Randerson, Dave Schimel, and TRENDY modelers (Stephen Sitch, Pierre Friedlingstein, Vivek Arora, Atul Jain, Markus Kautz, Danica Lobardozzi, Sebastian Lienert, Julia Nabel, Benjamin Poulter, Nicolas Vuichard, Andy Wiltshire, and Ning Zeng) for their comments and suggestions in preparing this paper. Resources supporting this work were provided by the NASA High\u2010End Computing (HEC) Program through the NASA Advanced Supercomputing (NAS) division at Ames Research Center. We acknowledge the funding support from NASA Carbon Cycle Science program and OCO\u20102/3 Science Team program. Part of the research was carried out at Jet Propulsion Laboratory, Caltech. \n\n\nData Availability Statement: The sources of all the data used in this paper are listed in Table S1. \n\nThe authors declare no conflicts of interest relevant to this study.\n\nPublished - 2020AV000228.pdf
Accepted Version - aga220053-sup-0005-2020av000228-second_revision_of_manuscript__accepted_-s04.pdf
Submitted - aga220053-sup-0002-2020av000228-original_version_of_manuscript-s01.pdf
Submitted - aga220053-sup-0004-2020av000228-first_revision_of_manuscript-s03.pdf
Supplemental Material - aga220053-sup-0001-2020av000228-si.pdf
Supplemental Material - aga220053-sup-0003-2020av000228-peer_review_history-s02.pdf
Supplemental Material - aga220053-sup-0006-2020av000228-author_response_to_peer_review_comments-s05.pdf
", "abstract": "Since the 1960s, carbon cycling in the high\u2010latitude northern forest (HLNF) has experienced dramatic changes: Most of the forest is greening and net carbon uptake from the atmosphere has increased. During the same time period, the CO\u2082 seasonal cycle amplitude (SCA) has increased by ~50% or more. Disentangling complex processes that drive these changes has been challenging. In this study, we substitute spatial sensitivity to temperature for time to quantify the impact of temperature increase on gross primary production (GPP), total ecosystem respiration (TER), the fraction of Photosynthetic Active Radiation (fPAR), and the resulted contribution of these changes in amplifying the CO\u2082 SCA over the HLNF since 1960s. We use the spatial heterogeneity of GPP inferred from solar\u2010induced chlorophyll Fluorescence in combination with net ecosystem exchange (NEE) inferred from column CO\u2082 observations made between 2015 and 2017 from NASA's Orbiting Carbon Observatory\u20102. We find that three quarters of the spatial variations in GPP can be explained by the spatial variation in the growing season mean temperature (GSMT). The long term hindcast captures both the magnitude and spatial variability of the trends in observed fPAR. We estimate that between 1960 and 2010, the increase in GSMT enhanced both GPP and the SCA of NEE by ~20%. The calculated enhancement of NEE due to increase in GSMT contributes 56\u201372% of the trend in the CO\u2082 SCA at high latitudes, much larger than simulations by most biogeochemical models.", "date": "2020-12", "date_type": "published", "publication": "AGU Advances", "volume": "1", "number": "4", "publisher": "American Geophysical Union", "pagerange": "Art. No. e2020AV000228", "id_number": "CaltechAUTHORS:20201124-131616305", "issn": "2576-604X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201124-131616305", "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": "10.1029/2020AV000228", "primary_object": { "basename": "aga220053-sup-0003-2020av000228-peer_review_history-s02.pdf", "url": "https://authors.library.caltech.edu/records/0kptp-jnp85/files/aga220053-sup-0003-2020av000228-peer_review_history-s02.pdf" }, "related_objects": [ { "basename": "aga220053-sup-0004-2020av000228-first_revision_of_manuscript-s03.pdf", "url": "https://authors.library.caltech.edu/records/0kptp-jnp85/files/aga220053-sup-0004-2020av000228-first_revision_of_manuscript-s03.pdf" }, { "basename": "aga220053-sup-0005-2020av000228-second_revision_of_manuscript__accepted_-s04.pdf", "url": "https://authors.library.caltech.edu/records/0kptp-jnp85/files/aga220053-sup-0005-2020av000228-second_revision_of_manuscript__accepted_-s04.pdf" }, { "basename": "aga220053-sup-0006-2020av000228-author_response_to_peer_review_comments-s05.pdf", "url": "https://authors.library.caltech.edu/records/0kptp-jnp85/files/aga220053-sup-0006-2020av000228-author_response_to_peer_review_comments-s05.pdf" }, { "basename": "2020AV000228.pdf", "url": "https://authors.library.caltech.edu/records/0kptp-jnp85/files/2020AV000228.pdf" }, { "basename": "aga220053-sup-0001-2020av000228-si.pdf", "url": "https://authors.library.caltech.edu/records/0kptp-jnp85/files/aga220053-sup-0001-2020av000228-si.pdf" }, { "basename": "aga220053-sup-0002-2020av000228-original_version_of_manuscript-s01.pdf", "url": "https://authors.library.caltech.edu/records/0kptp-jnp85/files/aga220053-sup-0002-2020av000228-original_version_of_manuscript-s01.pdf" } ], "resource_type": "article", "pub_year": "2020", "author_list": "Liu, Junjie; Wennberg, P. O.; et el." }, { "id": "https://authors.library.caltech.edu/records/am1ef-gt617", "eprint_id": 106193, "eprint_status": "archive", "datestamp": "2023-08-22 07:12:08", "lastmod": "2023-10-20 23:11:11", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Xu-Lu", "name": { "family": "Xu", "given": "Lu" }, "orcid": "0000-0002-0021-9876" }, { "id": "M\u00f8ller-Kristian-H", "name": { "family": "M\u00f8ller", "given": "Kristian H." }, "orcid": "0000-0001-8070-8516" }, { "id": "Crounse-John-D", "name": { "family": "Crounse", "given": "John D." }, "orcid": "0000-0001-5443-729X" }, { "id": "Kjaergaard-Henrik-G", "name": { "family": "Kjaergaard", "given": "Henrik G." }, "orcid": "0000-0002-7275-8297" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "New Insights into the Radical Chemistry and Product Distribution in the OH-Initiated Oxidation of Benzene", "ispublished": "pub", "full_text_status": "public", "keywords": "Hydrocarbons, Anions, Aromatic compounds, Oxidation, Molecular structure", "note": "\u00a9 2020 American Chemical Society. \n\nReceived 17 July 2020. Accepted 6 October 2020. Revised 5 October 2020. Published online 21 October 2020. \n\nL.X., J.D.C., and P.O.W. thank NASA (NNX14AP46G) and NSF (CHE-1905340) for supporting this work. K.H.M. and H.G.K. acknowledge funding from the University of Copenhagen and the Independent Research Fund Denmark. \n\nThe authors declare no competing financial interest.\n\nSupplemental Material - es0c04780_si_001.pdf
", "abstract": "Emissions of aromatic compounds cause air pollution and detrimental health effects. Here, we explore the reaction kinetics and products of key radicals in benzene photo-oxidation. After initial OH addition and reaction with O\u2082, the effective production rates of phenol and bicyclic peroxy radical (BCP-peroxy) are experimentally constrained at 295 K to be 420 \u00b1 80 and 370 \u00b1 70 s\u207b\u00b9, respectively. These rates lead to approximately 53% yield for phenol and 47% yield for BCP-peroxy under atmospheric conditions. The reaction of BCP-peroxy with NO produces bicyclic hydroxy nitrate with a branching ratio <0.2%, indicating efficient NO_x recycling. Similarly, the reaction of BCP-peroxy with HO\u2082 largely recycles HO_x, producing the corresponding bicyclic alkoxy radical (BCP-oxy). Because of the presence of C\u2013C double bonds and multiple functional groups, the chemistry of BCP-oxy and other alkoxy radicals in the system is diverse. Experimental results suggest the aldehydic H-shift and ring-closure to produce an epoxide functionality could be competitive with classic decomposition of alkoxy radicals. These reactions are potential sources of highly oxygenated molecules. Finally, despite the large number of compounds observed in our study, we are unable to account for \u223c20% of the carbon flow.", "date": "2020-11-03", "date_type": "published", "publication": "Environmental Science and Technology", "volume": "54", "number": "21", "publisher": "American Chemical Society", "pagerange": "13467-13477", "id_number": "CaltechAUTHORS:20201021-151807739", "issn": "0013-936X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201021-151807739", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NNX14AP46G" }, { "agency": "NSF", "grant_number": "CHE-1905340" }, { "agency": "University of Copenhagen" }, { "agency": "Independent Research Fund Denmark" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1021/acs.est.0c04780", "primary_object": { "basename": "es0c04780_si_001.pdf", "url": "https://authors.library.caltech.edu/records/am1ef-gt617/files/es0c04780_si_001.pdf" }, "resource_type": "article", "pub_year": "2020", "author_list": "Xu, Lu; M\u00f8ller, Kristian H.; et el." }, { "id": "https://authors.library.caltech.edu/records/mhd9j-9jb42", "eprint_id": 105025, "eprint_status": "archive", "datestamp": "2023-08-22 06:03:32", "lastmod": "2023-10-23 17:20:18", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Byrne-Brendan", "name": { "family": "Byrne", "given": "B." }, "orcid": "0000-0003-0619-3045" }, { "id": "Liu-Junjie", "name": { "family": "Liu", "given": "J." }, "orcid": "0000-0002-7184-6594" }, { "id": "Lee-Meemong", "name": { "family": "Lee", "given": "M." }, "orcid": "0000-0002-8797-8209" }, { "id": "Baker-Ian", "name": { "family": "Baker", "given": "I." }, "orcid": "0000-0001-5162-1956" }, { "id": "Bowman-Kevin-W", "name": { "family": "Bowman", "given": "K. W." }, "orcid": "0000-0002-8659-1117" }, { "id": "Deutscher-Nicholas-M", "name": { "family": "Deutscher", "given": "N. M." }, "orcid": "0000-0002-2906-2577" }, { "id": "Feist-Dietrich-G", "name": { "family": "Feist", "given": "D. G." }, "orcid": "0000-0002-5890-6687" }, { "id": "Griffith-David-W-T", "name": { "family": "Griffith", "given": "D. W. T." }, "orcid": "0000-0002-7986-1924" }, { "id": "Iraci-Laura-T", "name": { "family": "Iraci", "given": "L. T." }, "orcid": "0000-0002-2859-5259" }, { "id": "Kiel-Matth\u00e4us", "name": { "family": "Kiel", "given": "M." }, "orcid": "0000-0002-9784-962X" }, { "id": "Kimball-John-S", "name": { "family": "Kimball", "given": "J. S." }, "orcid": "0000-0002-5493-5878" }, { "id": "Miller-Charles-E", "name": { "family": "Miller", "given": "C. E." }, "orcid": "0000-0002-9380-4838" }, { "id": "Morino-Isamu", "name": { "family": "Morino", "given": "I." }, "orcid": "0000-0003-2720-1569" }, { "id": "Parazoo-Nicholas-C", "name": { "family": "Parazoo", "given": "N. C." }, "orcid": "0000-0002-4424-7780" }, { "id": "Petri-Christof", "name": { "family": "Petri", "given": "C." }, "orcid": "0000-0002-7010-5532" }, { "id": "Roehl-Coleen-M", "name": { "family": "Roehl", "given": "C. M." }, "orcid": "0000-0001-5383-8462" }, { "id": "Sha-Mahesh-Kumar", "name": { "family": "Sha", "given": "M. K." }, "orcid": "0000-0003-1440-1529" }, { "id": "Strong-Kimberly", "name": { "family": "Strong", "given": "K." }, "orcid": "0000-0001-9947-1053" }, { "id": "Velazco-Voltaire-A", "name": { "family": "Velazco", "given": "V. A." }, "orcid": "0000-0002-1376-438X" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Wunch-Debra", "name": { "family": "Wunch", "given": "D." }, "orcid": "0000-0002-4924-0377" } ] }, "title": "Improved Constraints on Northern Extratropical CO\u2082 Fluxes Obtained by Combining Surface-Based and Space-Based Atmospheric CO\u2082 Measurements", "ispublished": "pub", "full_text_status": "public", "keywords": "carbon cycle; CO2 flux; data assimilation; GOSAT; TCCON; OCO\u20102", "note": "\u00a9 2020 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\nIssue Online: 26 July 2020; Version of Record online: 26 July 2020; Accepted manuscript online: 24 June 2020; Manuscript accepted: 13 June 2020; Manuscript revised: 05 May 2020; Manuscript received: 08 November 2019. \n\nBB was supported by an appointment to the NASA Postdoctoral Program at the Jet Propulsion Laboratory, administered by Universities Space Research Association under contract with NASA. JL was supported by the NASA OCO2/3 science team program NNH17ZDA001N\u2010OCO2. KWB was supported by the NASA Carbon Monitoring System (CMS) project (NNH16ZDA001N\u2010CMS). The research carried out at the Jet Propulsion Laboratory, California Institute of Technology, was under a contract with the National Aeronautics and Space Administration. Resources supporting this work were provided by the NASA High\u2010End Computing (HEC) Program through the NASA Advanced Supercomputing (NAS) Division at Ames Research Center. Odiac project is supported by Greenhouse Gas Observing SATellite (GOSAT) project, National Institute for Environmental Studies (NIES), Japan. We thank S. Basu for providing downscaled ODIAC emissions. We thank T. Machida, H. Matsueda, Y. Sawa, and Y. Niwa for providing CONTRAIL measurements. The TCCON site at Reunion Island is operated by the Royal Belgian Institute for Space Aeronomy with financial support in 2014, 2015, 2016, 2017, 2018, and 2019 under the EU project ICOS\u2010Inwire and the ministerial decree for ICOS (FR/35/IC2) and local activities supported by LACy/UMR8105 Universit de La Reunion. The TCCON project for Rikubetsu site is supported in part by the GOSAT series project. The Ascension Island TCCON station has been supported by the European Space Agency (ESA) under grant 4000120088/17/I\u2010EF and by the German Bundesministerium fur Wirtschaft und Energie (BMWi) under grants 50EE1711C and 50EE1711E. We thank the ESA Ariane Tracking Station at North East Bay, Ascension Island, for hosting and local support. \n\nData Availability Statement: TCCON data were obtained from the TCCON Data Archive, hosted by CaltechDATA (http://tccondata.org). FLUXCOM products were obtained from the Data Portal of the Max Planck Institute for Biochemistry [https://www.bgc-jena.mpg.de]. MERRA\u20102 products were downloaded from MDISC (https://gmao.gsfc.nasa.gov/reanalysis/MERRA-2/), managed by the NASA Goddard Earth Sciences (GES) Data and Information Services Center (DISC). GOSAT OCFP v7.1 urn:x-wiley:jgrd:media:jgrd56355:jgrd56355-math-0041 retrievals were downloaded from the Copernicus Climate Change Service website (https://cds.climate.copernicus.eu). Version 4.1 of the GLOBALVIEW plus package was downloaded from http://www.esrl.noaa.gov/gmd/ccgg/obspack/. ESA CCI soil moisture data was downloaded from https://www.esa-soilmoisture-cci.org/. Odiac emissions data set was provided by T. Oda of Colorado State University, Fort Collins CO, USA/Global Monitoring Division, NOAA Earth System Research Laboratory, Boulder CO, USA. GOSAT and OCO\u20102 ACOS retrievals were downloaded from the CO2 virtual science data environment: https://co2.jpl.nasa.gov/. Prior and posterior NEE and Ocean fluxes presented in this study will be available for download from https://data.nas.nasa.gov and https://cmsflux.jpl.nasa.gov/. The JR\u2010STATION data set is available from the Global Environmental Database, hosted by Center for Global Environmental Research (CGER), National Institute for Environmental Studies (NIES) (http://db.cger.nies.go.jp/portal/geds/atmosphericAnd OceanicMonitoring).\n\nPublished - 2019JD032029.pdf
Submitted - essoar.10501108.2.pdf
Supplemental Material - jgrd56355-sup-0001-text_si-s01.pdf
", "abstract": "Top\u2010down estimates of CO\u2082 fluxes are typically constrained by either surface\u2010based or space\u2010based CO\u2082 observations. Both of these measurement types have spatial and temporal gaps in observational coverage that can lead to differences in inferred fluxes. Assimilating both surface\u2010based and space\u2010based measurements concurrently in a flux inversion framework improves observational coverage and reduces sampling related artifacts. This study examines the consistency of flux constraints provided by these different observations and the potential to combine them by performing a series of 6\u2010year (2010\u20132015) CO\u2082 flux inversions. Flux inversions are performed assimilating surface\u2010based measurements from the in situ and flask network, measurements from the Total Carbon Column Observing Network (TCCON), and space\u2010based measurements from the Greenhouse Gases Observing Satellite (GOSAT), or all three data sets combined. Combining the data sets results in more precise flux estimates for subcontinental regions relative to any of the data sets alone. Combining the data sets also improves the accuracy of the posterior fluxes, based on reduced root\u2010mean\u2010square differences between posterior flux\u2010simulated CO\u2082 and aircraft\u2010based CO\u2082 over midlatitude regions (0.33\u20130.56\u2009ppm) in comparison to GOSAT (0.37\u20130.61\u2009ppm), TCCON (0.50\u20130.68\u2009ppm), or in situ and flask measurements (0.46\u20130.56\u2009ppm) alone. These results suggest that surface\u2010based and GOSAT measurements give complementary constraints on CO\u2082 fluxes in the northern extratropics and can be combined in flux inversions to improve constraints on regional fluxes. This stands in contrast with many earlier attempts to combine these data sets and suggests that improvements in the NASA Atmospheric CO\u2082 Observations from Space (ACOS) retrieval algorithm have significantly improved the consistency of space\u2010based and surface\u2010based flux constraints.", "date": "2020-08-16", "date_type": "published", "publication": "Journal of Geophysical Research. Atmospheres", "volume": "125", "number": "15", "publisher": "American Geophysical Union", "pagerange": "Art. No. e2019JD032029", "id_number": "CaltechAUTHORS:20200819-102214184", "issn": "2169-897X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200819-102214184", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA Postdoctoral Program" }, { "agency": "NASA", "grant_number": "NNH17ZDA001N-OCO2" }, { "agency": "NASA", "grant_number": "NNH16ZDA001N\u2010CMS" }, { "agency": "NASA/JPL/Caltech" }, { "agency": "National Institute for Environmental Studies (Japan)" }, { "agency": "Royal Belgian Institute for Space Aeronomy" }, { "agency": "European Union", "grant_number": "FR/35/IC2" }, { "agency": "Universit\u00e9 de La R\u00e9union", "grant_number": "LACy/UMR8105" }, { "agency": "European Space Agency (ESA)", "grant_number": "4000120088/17/I\u2010EF" }, { "agency": "Bundesministerium f\u00fcr Wirtschaft und Energie (BMWi)", "grant_number": "50EE1711C" }, { "agency": "Bundesministerium f\u00fcr Wirtschaft und Energie (BMWi)", "grant_number": "50EE1711E" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2019jd032029", "primary_object": { "basename": "jgrd56355-sup-0001-text_si-s01.pdf", "url": "https://authors.library.caltech.edu/records/mhd9j-9jb42/files/jgrd56355-sup-0001-text_si-s01.pdf" }, "related_objects": [ { "basename": "2019JD032029.pdf", "url": "https://authors.library.caltech.edu/records/mhd9j-9jb42/files/2019JD032029.pdf" }, { "basename": "essoar.10501108.2.pdf", "url": "https://authors.library.caltech.edu/records/mhd9j-9jb42/files/essoar.10501108.2.pdf" } ], "resource_type": "article", "pub_year": "2020", "author_list": "Byrne, B.; Liu, J.; et el." }, { "id": "https://authors.library.caltech.edu/records/44xpq-s6302", "eprint_id": 105240, "eprint_status": "archive", "datestamp": "2023-08-22 06:02:13", "lastmod": "2023-10-20 21:29:38", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Simpson-I-J", "name": { "family": "Simpson", "given": "Isobel J." } }, { "name": { "family": "Blake", "given": "Donald R." } }, { "name": { "family": "Blake", "given": "Nicola J." } }, { "name": { "family": "Meinardi", "given": "Simone" } }, { "name": { "family": "Barletta", "given": "Barbara" } }, { "name": { "family": "Hughes", "given": "Stacey C." } }, { "name": { "family": "Fleming", "given": "Lauren T." } }, { "name": { "family": "Crawford", "given": "James H." } }, { "name": { "family": "Diskin", "given": "Glenn S." } }, { "name": { "family": "Emmons", "given": "Louisa K." } }, { "name": { "family": "Fried", "given": "Alan" } }, { "name": { "family": "Guo", "given": "Hai" } }, { "name": { "family": "Peterson", "given": "David A." } }, { "name": { "family": "Wisthaler", "given": "Armin" } }, { "name": { "family": "Woo", "given": "Jung-Hun" } }, { "name": { "family": "Barr\u00e9", "given": "Jerome" } }, { "name": { "family": "Gaubert", "given": "Benjamin" } }, { "name": { "family": "Kim", "given": "Jinseok" } }, { "id": "Kim-Michelle-J", "name": { "family": "Kim", "given": "Michelle J." }, "orcid": "0000-0002-4922-4334" }, { "name": { "family": "Kim", "given": "Younha" } }, { "name": { "family": "Knote", "given": "Christoph" } }, { "name": { "family": "Mikoviny", "given": "Tomas" } }, { "name": { "family": "Pusede", "given": "Sally E." } }, { "name": { "family": "Schroeder", "given": "Jason R." } }, { "name": { "family": "Wang", "given": "Yu" } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" }, { "name": { "family": "Zeng", "given": "Lewei" } } ] }, "title": "Characterization, sources and reactivity of volatile organic compounds (VOCs) in Seoul and surrounding regions during KORUS-AQ", "ispublished": "pub", "full_text_status": "public", "keywords": "VOCs, Seoul, Korea, KORUS-AQ, Source apportionment, OH reactivity", "note": "\u00a9 2020 University of California Press. CC BY 4.0. \n\nSubmitted on 06 Dec 2019; Accepted on 23 Jun 2020;\nPublished on 11 Aug 2020. \n \nThe KORUS-AQ mission was jointly funded by NASA and the Korean National Institute of Environmental Research (NIER). We gratefully acknowledge the KORUS-AQ crew and science team, and the technicians and staff at UC-Irvine who supported the WAS effort (Barbara Chisholm, Gloria Liu Weitz, Brent Love, Nick Vizenor, Rafe Day). The NO_y and O\u2083 data were provided courtesy of Andrew Weinheimer and Denise Montzka (NCAR), and John Crounse provided HCN data. The PTR-ToF-MS measurements were supported by the Austrian Federal Ministry for Transport, Innovation and Technology (bmvit) through the Austrian Space Applications Programme (ASAP) of the Austrian Research Promotion Agency (FFG). The PTR-ToF-MS instrument team (P. Eichler, L. Kaser, M. M\u00fcller) is acknowledged for their support in the field and during the mission preparation phase, and Ionicon Analytik is acknowledged for instrumental support. We also thank Daniel Bon (Colorado Dept. of Public Health & Environment) for helpful discussions on PMF, Hannah Halliday (NASA Langley) and Meehye Lee (Korea University) for helpful discussions on regional source influences, Saewung Kim (UCI) for coordination during the MAPS-2015 campaign, and Yanhong Zhu (Jinan University) for providing wheat count hotspots during the KORUS-AQ timeframe. We thank the UC White Mountain Research Center for use of the Crooked Creek Station for gathering air samples for use as working standards. Finally we thank numerous colleagues for valuable discussions and feedback on the interpretation of the source apportionment results. \n\nThe authors have no competing interests to declare. \n\nAuthor contributions: IJS interpreted the data and wrote the manuscript. DRB oversaw the WAS contribution to KORUS-AQ and performed data analysis and interpretation. NJB oversaw WAS field operations, and NJB, SCH and LTF acquired WAS data. SM oversaw WAS laboratory operations and performed data analysis. BB oversaw WAS data management. JHC and JRS performed photochemical box modeling calculations and data interpretation. GSD and SEP provided CO and CH\u2084 measurements. HG, DW and IZ supported the PMF analysis. DAP oversaw the meteorological analysis. AW and TM performed PTR-ToF-MS analysis. JHW, JK and YK oversaw the KORUSv5 emission inventory and provided data for the paper. AF led the CH\u2082O analysis. LKE, JB and BG provided CAM-chem model simulations. CK provided the FLEXPART back trajectories. POW and MJK provided HCN data. All co-authors revised the manuscript and approved the submitted version for publication. \n\nData Accessibility Statement: All observational data from the KORUS-AQ mission, including the WAS VOC data, are archived at: https://www-air.larc.nasa.gov/cgi-bin/ArcView/korusaq.\n\nPublished - 434-7405-2-PB.pdf
Supplemental Material - elementa-8-419-s1.pdf
", "abstract": "The Korea-United States Air Quality Study (KORUS-AQ) took place in spring 2016 to better understand air pollution in Korea. In support of KORUS-AQ, 2554 whole air samples (WAS) were collected aboard the NASA DC-8 research aircraft and analyzed for 82 C\u2081\u2013C\u2081\u2080 volatile organic compounds (VOCs) using multi-column gas chromatography. Together with fast-response measurements from other groups, the air samples were used to characterize the VOC composition in Seoul and surrounding regions, determine which VOCs are major ozone precursors in Seoul, and identify the sources of these reactive VOCs. (1) The WAS VOCs showed distinct signatures depending on their source origins. Air collected over Seoul had abundant ethane, propane, toluene and n-butane while plumes from the Daesan petrochemical complex were rich in ethene, C\u2082\u2013C\u2086 alkanes and benzene. Carbonyl sulfide (COS), CFC-113, CFC-114, carbon tetrachloride (CCl\u2084) and 1,2-dichloroethane were good tracers of air originating from China. CFC-11 was also elevated in air from China but was surprisingly more elevated in air over Seoul. (2) Methanol, isoprene, toluene, xylenes and ethene were strong individual contributors to OH reactivity in Seoul. However methanol contributed less to ozone formation based on photochemical box modeling, which better accounts for radical chemistry. (3) Positive Matrix Factorization (PMF) and other techniques indicated a mix of VOC source influences in Seoul, including solvents, traffic, biogenic, and long-range transport. The solvent and traffic sources were roughly equal using PMF, and the solvents source was stronger in the KORUS-AQ emission inventory. Based on PMF, ethene and propene were primarily associated with traffic, and toluene, ethylbenzene and xylenes with solvents, especially non-paint solvents for toluene and paint solvents for ethylbenzene and xylenes. This suggests that VOC control strategies in Seoul could continue to target vehicle exhaust and paint solvents, with additional regulations to limit the VOC content in a variety of non-paint solvents.", "date": "2020-08-11", "date_type": "published", "publication": "Elementa: Science of the Anthropocene", "volume": "8", "number": "1", "publisher": "University of California Press", "pagerange": "Art. No. 37", "id_number": "CaltechAUTHORS:20200903-122323790", "issn": "2325-1026", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200903-122323790", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA" }, { "agency": "National Institute of Environmental Research (NIER)" }, { "agency": "Bundesministerium f\u00fcr Verkehr, Innovation und Technologie (BMVIT)" }, { "agency": "\u00d6sterreichische Forschungsf\u00f6rderungsgesellschaft (FFG)" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1525/elementa.434", "primary_object": { "basename": "elementa-8-419-s1.pdf", "url": "https://authors.library.caltech.edu/records/44xpq-s6302/files/elementa-8-419-s1.pdf" }, "related_objects": [ { "basename": "434-7405-2-PB.pdf", "url": "https://authors.library.caltech.edu/records/44xpq-s6302/files/434-7405-2-PB.pdf" } ], "resource_type": "article", "pub_year": "2020", "author_list": "Simpson, Isobel J.; Blake, Donald R.; et el." }, { "id": "https://authors.library.caltech.edu/records/rvdet-b8b65", "eprint_id": 104537, "eprint_status": "archive", "datestamp": "2023-08-22 05:36:05", "lastmod": "2023-10-20 20:34:44", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Travis-K-R", "name": { "family": "Travis", "given": "Katherine R." }, "orcid": "0000-0003-1628-0353" }, { "name": { "family": "Heald", "given": "Colette L." }, "orcid": "0000-0003-2894-5738" }, { "id": "Allen-H-M", "name": { "family": "Allen", "given": "Hannah M." }, "orcid": "0000-0002-4218-5133" }, { "name": { "family": "Apel", "given": "Eric C." }, "orcid": "0000-0001-9421-818X" }, { "name": { "family": "Arnold", "given": "Stephen R." } }, { "name": { "family": "Blake", "given": "Donald R." } }, { "name": { "family": "Brune", "given": "William H." }, "orcid": "0000-0002-1609-4051" }, { "name": { "family": "Chen", "given": "Xin" }, "orcid": "0000-0002-0952-0008" }, { "name": { "family": "Commane", "given": "R\u00f3is\u00edn" }, "orcid": "0000-0003-1373-1550" }, { "id": "Crounse-J-D", "name": { "family": "Crounse", "given": "John D." }, "orcid": "0000-0001-5443-729X" }, { "name": { "family": "Daube", "given": "Bruce C." } }, { "name": { "family": "Diskin", "given": "Glenn S." }, "orcid": "0000-0002-3617-0269" }, { "name": { "family": "Elkins", "given": "James W." }, "orcid": "0000-0003-4701-3100" }, { "name": { "family": "Evans", "given": "Mathew J." }, "orcid": "0000-0003-4775-032X" }, { "name": { "family": "Hall", "given": "Samuel R." }, "orcid": "0000-0002-2060-7112" }, { "name": { "family": "Hintsa", "given": "Eric J." }, "orcid": "0000-0002-5289-630X" }, { "name": { "family": "Hornbrook", "given": "Rebecca S." }, "orcid": "0000-0002-6304-6554" }, { "name": { "family": "Kasibhatla", "given": "Prasad S." }, "orcid": "0000-0003-3562-3737" }, { "id": "Kim-Michelle-J", "name": { "family": "Kim", "given": "Michelle J." }, "orcid": "0000-0002-4922-4334" }, { "name": { "family": "Luo", "given": "Gan" }, "orcid": "0000-0002-9588-7008" }, { "name": { "family": "McKain", "given": "Kathryn" }, "orcid": "0000-0002-8323-5758" }, { "name": { "family": "Millet", "given": "Dylan B." }, "orcid": "0000-0003-3076-125X" }, { "name": { "family": "Moore", "given": "Fred L." }, "orcid": "0000-0002-8461-2535" }, { "name": { "family": "Peischl", "given": "Jeffrey" }, "orcid": "0000-0002-9320-7101" }, { "name": { "family": "Ryerson", "given": "Thomas B." }, "orcid": "0000-0003-2800-7581" }, { "name": { "family": "Sherwen", "given": "Tom\u00e1s" }, "orcid": "0000-0002-3006-3876" }, { "name": { "family": "Thames", "given": "Alexander B." } }, { "name": { "family": "Ullmann", "given": "Kirk" }, "orcid": "0000-0002-4724-9634" }, { "name": { "family": "Wang", "given": "Xuan" }, "orcid": "0000-0002-8532-5773" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" }, { "name": { "family": "Wolfe", "given": "Glenn M." }, "orcid": "0000-0001-6586-4043" }, { "name": { "family": "Yu", "given": "Fangqun" }, "orcid": "0000-0001-8862-4835" } ] }, "title": "Constraining remote oxidation capacity with ATom observations", "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: 11 Oct 2019 \u2013 Discussion started: 03 Jan 2020 \u2013 Revised: 12 Apr 2020 \u2013 Accepted: 03 May 2020 \u2013 Published: 03 Jul 2020. \n\nWe are grateful for helpful conversations and advice from Andrea Molod, Rachel Silvern, Elo\u00efse Marais, Sarah Safieddine, Martin Br\u00fcggemann, Christian George, and James Crawford. We acknowledge Tom Hanisco and Jason St. Clair for the use of their formaldehyde observations from ATom and Barbara Barletta and Simone Meinardi for their contribution to the UCI WAS measurements. \n\nThis research has been supported by the National Science Foundation (grant no. AGS-1564495), the National Center for Atmospheric Research (grant no. 1852977), the National Oceanic and Atmospheric Administration (grant no. NA18OAR4310110), and the National Aeronautics and Space Administration (grant no. NNX14AP89G, grant no. IAT NNH15AB12I, grant no. NNX17AG35G, grant no. NNX15AG61A, grant no. NNX15AG71A). \n\nAuthor contributions. CLH and KRT designed the study and wrote the paper with input from the co-authors. KRT modified the code, performed the simulations, and led the analysis. HMA, ECA, DRB, WHB, RC, JDC, BCD, GSD, JWE, SRH, EJH, SRH, MJK, KM, FLM, JP, TBR, ABT, KU, POW, and GMW provided ATom measurements used in the analysis. XW provided the model code for the sensitivity runs including acid displacement of chloride on coarse-mode sea-salt aerosols. TS, ME, and PSK provided the model code for the photolysis of particulate nitrate. GL and FY were responsible for the code for the revised treatment of wet scavenging in the model. DBM and XC provided the methanol seawater concentration and assisted in the ocean budget analysis. SRA provided the biogenic ocean isoprene emissions. \n\nData availability. The ATom-1 and ATom-2 data (Wofsy et al., 2018) are available here: https://doi.org/10.3334/ORNLDAAC/1581. \n\nThe supplement related to this article is available online at: https://doi.org/10.5194/acp-20-7753-2020-supplement. \n\nThe authors declare that they have no conflict of interest. \n\nReview statement. This paper was edited by Yafang Cheng and reviewed by three anonymous referees.\n\nPublished - acp-20-7753-2020.pdf
Supplemental Material - acp-20-7753-2020-supplement.pdf
", "abstract": "The global oxidation capacity, defined as the tropospheric mean concentration of the hydroxyl radical (OH), controls the lifetime of reactive trace gases in the atmosphere such as methane and carbon monoxide (CO). Models tend to underestimate the methane lifetime and CO concentrations throughout the troposphere, which is consistent with excessive OH. Approximately half of the oxidation of methane and non-methane volatile organic compounds (VOCs) is thought to occur over the oceans where oxidant chemistry has received little validation due to a lack of observational constraints. We use observations from the first two deployments of the NASA ATom aircraft campaign during July\u2013August 2016 and January\u2013February 2017 to evaluate the oxidation capacity over the remote oceans and its representation by the GEOS-Chem chemical transport model. The model successfully simulates the magnitude and vertical profile of remote OH within the measurement uncertainties. Comparisons against the drivers of OH production (water vapor, ozone, and N_Oy concentrations, ozone photolysis frequencies) also show minimal bias, with the exception of wintertime NO_y. The severe model overestimate of NO_y during this period may indicate insufficient wet scavenging and/or missing loss on sea-salt aerosols. Large uncertainties in these processes require further study to improve simulated NO_y partitioning and removal in the troposphere, but preliminary tests suggest that their overall impact could marginally reduce the model bias in tropospheric OH. During the ATom-1 deployment, OH reactivity (OHR) below 3\u2009km is significantly enhanced, and this is not captured by the sum of its measured components (cOHR_(obs)) or by the model (cOHR_(mod)). This enhancement could suggest missing reactive VOCs but cannot be explained by a comprehensive simulation of both biotic and abiotic ocean sources of VOCs. Additional sources of VOC reactivity in this region are difficult to reconcile with the full suite of ATom measurement constraints. The model generally reproduces the magnitude and seasonality of cOHR_(obs) but underestimates the contribution of oxygenated VOCs, mainly acetaldehyde, which is severely underestimated throughout the troposphere despite its calculated lifetime of less than a day. Missing model acetaldehyde in previous studies was attributed to measurement uncertainties that have been largely resolved. Observations of peroxyacetic acid (PAA) provide new support for remote levels of acetaldehyde. The underestimate in both model acetaldehyde and PAA is present throughout the year in both hemispheres and peaks during Northern Hemisphere summer. The addition of ocean sources of VOCs in the model increases cOHR_(mod) by 3\u2009% to 9\u2009% and improves model\u2013measurement agreement for acetaldehyde, particularly in winter, but cannot resolve the model summertime bias. Doing so would require 100\u2009Tg\u2009yr\u207b\u00b9 of a long-lived unknown precursor throughout the year with significant additional emissions in the Northern Hemisphere summer. Improving the model bias for remote acetaldehyde and PAA is unlikely to fully resolve previously reported model global biases in OH and methane lifetime, suggesting that future work should examine the sources and sinks of OH over land.", "date": "2020-07-03", "date_type": "published", "publication": "Atmospheric Chemistry and Physics", "volume": "20", "number": "13", "publisher": "European Geosciences Union", "pagerange": "7753-7781", "id_number": "CaltechAUTHORS:20200723-122440518", "issn": "1680-7324", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200723-122440518", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "AGS-1564495" }, { "agency": "National Center for Atmospheric Research (NCAR)", "grant_number": "1852977" }, { "agency": "National Oceanic and Atmospheric Administration (NOAA)", "grant_number": "NA18OAR4310110" }, { "agency": "NASA", "grant_number": "NNX14AP89G" }, { "agency": "NASA", "grant_number": "NNH15AB12I" }, { "agency": "NASA", "grant_number": "NNX17AG35G" }, { "agency": "NASA", "grant_number": "NNX15AG61A" }, { "agency": "NASA", "grant_number": "NNX15AG71A" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/acp-20-7753-2020", "primary_object": { "basename": "acp-20-7753-2020-supplement.pdf", "url": "https://authors.library.caltech.edu/records/rvdet-b8b65/files/acp-20-7753-2020-supplement.pdf" }, "related_objects": [ { "basename": "acp-20-7753-2020.pdf", "url": "https://authors.library.caltech.edu/records/rvdet-b8b65/files/acp-20-7753-2020.pdf" } ], "resource_type": "article", "pub_year": "2020", "author_list": "Travis, Katherine R.; Heald, Colette L.; et el." }, { "id": "https://authors.library.caltech.edu/records/7e5ax-q1805", "eprint_id": 102906, "eprint_status": "archive", "datestamp": "2023-08-22 05:23:40", "lastmod": "2023-10-20 00:36:58", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Copstein-Cuchiara-Gustavo", "name": { "family": "Cuchiara", "given": "G. C." }, "orcid": "0000-0001-6094-9187" }, { "id": "Fried-Alan", "name": { "family": "Fried", "given": "A." }, "orcid": "0000-0002-5230-3527" }, { "id": "Barth-Mary-C", "name": { "family": "Barth", "given": "M. C." }, "orcid": "0000-0002-9252-0286" }, { "id": "Bela-Megan", "name": { "family": "Bela", "given": "M." }, "orcid": "0000-0002-3998-9990" }, { "id": "Homeyer-Cameron-R", "name": { "family": "Homeyer", "given": "C. R." }, "orcid": "0000-0002-4883-6670" }, { "id": "Gaubert-Benjamin", "name": { "family": "Gaubert", "given": "B." }, "orcid": "0000-0002-6595-0686" }, { "id": "Walega-James", "name": { "family": "Walega", "given": "J." }, "orcid": "0000-0001-9167-8121" }, { "id": "Weibring-Petter", "name": { "family": "Weibring", "given": "P." }, "orcid": "0000-0001-9567-3803" }, { "id": "Richter-Dirk", "name": { "family": "Richter", "given": "D." }, "orcid": "0000-0002-2156-031X" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P." }, "orcid": "0000-0002-6126-3854" }, { "id": "Crounse-John-D", "name": { "family": "Crounse", "given": "J. D." }, "orcid": "0000-0001-5443-729X" }, { "id": "Kim-Michelle", "name": { "family": "Kim", "given": "M." }, "orcid": "0000-0002-4922-4334" }, { "id": "Diskin-Glenn-S", "name": { "family": "Diskin", "given": "G." }, "orcid": "0000-0002-3617-0269" }, { "id": "Hanisco-Thomas-M", "name": { "family": "Hanisco", "given": "T. M." }, "orcid": "0000-0001-9434-8507" }, { "id": "Wolfe-Glenn-M", "name": { "family": "Wolfe", "given": "G. M." }, "orcid": "0000-0001-6586-4043" }, { "id": "Beyersdorf-Andreas-J", "name": { "family": "Beyersdorf", "given": "A." }, "orcid": "0000-0002-4496-2557" }, { "id": "Peischl-Jeff", "name": { "family": "Peischl", "given": "J." }, "orcid": "0000-0002-9320-7101" }, { "id": "Pollack-Ilana-B", "name": { "family": "Pollack", "given": "I. B." }, "orcid": "0000-0001-7151-9756" }, { "id": "St-Clair-Jason-M", "name": { "family": "St. Clair", "given": "J. M." }, "orcid": "0000-0002-9367-5749" }, { "id": "Woods-Sarah", "name": { "family": "Woods", "given": "S." }, "orcid": "0000-0003-2174-8889" }, { "id": "Tanelli-Simone", "name": { "family": "Tanelli", "given": "S." }, "orcid": "0000-0001-5516-6882" }, { "id": "Bui-T-Paul", "name": { "family": "Bui", "given": "T. P." }, "orcid": "0000-0001-9189-0405" }, { "id": "Dean\u2010Day-Jonathan", "name": { "family": "Dean\u2010Day", "given": "J." }, "orcid": "0000-0003-2621-5774" }, { "id": "Huey-Greg-L", "name": { "family": "Huey", "given": "G. L." } }, { "id": "Heath-Nicholas", "name": { "family": "Heath", "given": "N." }, "orcid": "0000-0003-0328-4398" } ] }, "title": "Vertical Transport, Entrainment, and Scavenging Processes Affecting Trace Gases in a Modeled and Observed SEAC\u2074RS Case Study", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2020 American Geophysical Union. \n\nReceived 4 NOV 2019; Accepted 25 APR 2020; Accepted article online 29 APR 2020. \n\nWe would like to thank NASA for supporting this research through grant NNX17AH52G. NCAR is sponsored by the National Science Foundation. C. Homeyer was funded by NSF grant AGS\u20101522910. The authors thank Gabriele Pfister for providing additional WRF\u2010Chem information. The authors also thank Morgan Silverman and Gao Chen for providing SEAC\u2074RS formaldehyde comparison. We also thank NASA for supporting the SEAC\u2074RS campaign, the project leaders, and all the investigators for their data contributions. All data were obtained from the NASA Langley Research Center Atmospheric Science Data Center (https://www-air.larc.nasa.gov/cgi-bin/ArcView/seac4rs). We acknowledge use of the WRF\u2010Chem preprocessor tool (mozbc, fire_emiss, and bio_emiss) provided by the Atmospheric Chemistry Observations and Modeling Lab (ACOM) of NCAR and also the use of BOXMOX model provided by the University of Munich, Germany (http://boxmodeling.meteo.physik.uni-muenchen.de). Simone Tanelli's contributions were carried out at the Jet Propulsory Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration (80NM0018D0004).\n\nPublished - 2019JD031957.pdf
Supplemental Material - jgrd56231-sup-0001-sup-0001-text_si-s01.docx
", "abstract": "The convectively driven transport of soluble trace gases from the lower to the upper troposphere can occur on timescales of less than an hour, and recent studies suggest that microphysical scavenging is the dominant removal process of tropospheric ozone precursors. We examine the processes responsible for vertical transport, entrainment, and scavenging of soluble ozone precursors (formaldehyde and peroxides) for midlatitude convective storms sampled on 2 September 2013 during the Studies of Emissions, Atmospheric Composition, Clouds and Climate Coupling by Regional Surveys (SEAC\u2074RS) study. Cloud\u2010resolving simulations using the Weather Research and Forecasting with Chemistry model combined with aircraft measurements were performed to understand the effect of entrainment, scavenging efficiency (SE), and ice physics processes on these trace gases. Analysis of the observations revealed that the SEs of formaldehyde (43\u201353%) and hydrogen peroxide (~80\u201390%) were consistent between SEAC\u2074RS storms and the severe convection observed during the Deep Convective Clouds and Chemistry Experiment (DC3) campaign. However, methyl hydrogen peroxide SE was generally smaller in the SEAC\u2074RS storms (4%\u201327%) compared to DC3 convection. Predicted ice retention factors exhibit different values for some species compared to DC3, and we attribute these differences to variations in net precipitation production. The analyses show that much larger production of precipitation between condensation and freezing levels for DC3 severe convection compared to smaller SEAC\u2074RS storms is largely responsible for the lower amount of soluble gases transported to colder temperatures, reducing the amount of soluble gases which eventually interact with cloud ice particles.", "date": "2020-06-16", "date_type": "published", "publication": "Journal of Geophysical Research. Atmospheres", "volume": "125", "number": "11", "publisher": "American Geophysical Union", "pagerange": "Art. No. e2019JD031957", "id_number": "CaltechAUTHORS:20200429-125923209", "issn": "2169-897X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200429-125923209", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NNX17AH52G" }, { "agency": "NSF", "grant_number": "AGS-1522910" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2019jd031957", "primary_object": { "basename": "2019JD031957.pdf", "url": "https://authors.library.caltech.edu/records/7e5ax-q1805/files/2019JD031957.pdf" }, "related_objects": [ { "basename": "jgrd56231-sup-0001-sup-0001-text_si-s01.docx", "url": "https://authors.library.caltech.edu/records/7e5ax-q1805/files/jgrd56231-sup-0001-sup-0001-text_si-s01.docx" } ], "resource_type": "article", "pub_year": "2020", "author_list": "Cuchiara, G. C.; Fried, A.; et el." }, { "id": "https://authors.library.caltech.edu/records/16naj-hvh05", "eprint_id": 102598, "eprint_status": "archive", "datestamp": "2023-08-22 04:36:49", "lastmod": "2023-10-20 00:19:49", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Thames-Alexander-B", "name": { "family": "Thames", "given": "Alexander B." } }, { "name": { "family": "Brune", "given": "William H." }, "orcid": "0000-0002-1609-4051" }, { "name": { "family": "Miller", "given": "David O." } }, { "id": "Allen-H-M", "name": { "family": "Allen", "given": "Hannah M." } }, { "name": { "family": "Apel", "given": "Eric C." }, "orcid": "0000-0001-9421-818X" }, { "name": { "family": "Blake", "given": "Donald R." }, "orcid": "0000-0002-8283-5014" }, { "name": { "family": "Bui", "given": "T. Paul" } }, { "name": { "family": "Commane", "given": "Roisin" }, "orcid": "0000-0003-1373-1550" }, { "id": "Crounse-John-D", "name": { "family": "Crounse", "given": "John D." }, "orcid": "0000-0001-5443-729X" }, { "name": { "family": "Daube", "given": "Bruce C." } }, { "name": { "family": "Diskin", "given": "Glenn S." }, "orcid": "0000-0002-3617-0269" }, { "name": { "family": "DiGangi", "given": "Joshua P." }, "orcid": "0000-0002-6764-8624" }, { "name": { "family": "Elkins", "given": "James W." }, "orcid": "0000-0003-4701-3100" }, { "name": { "family": "Hall", "given": "Samuel R." }, "orcid": "0000-0002-2060-7112" }, { "name": { "family": "Hanisco", "given": "Thomas F." }, "orcid": "0000-0001-9434-8507" }, { "name": { "family": "Hannun", "given": "Reem A." }, "orcid": "0000-0001-5195-5307" }, { "name": { "family": "Hintsa", "given": "Eric" }, "orcid": "0000-0002-5289-630X" }, { "name": { "family": "Hornbrook", "given": "Rebecca S." }, "orcid": "0000-0002-6304-6554" }, { "id": "Kim-Michelle-J", "name": { "family": "Kim", "given": "Michelle J." }, "orcid": "0000-0002-4922-4334" }, { "name": { "family": "McKain", "given": "Kathryn" }, "orcid": "0000-0002-8323-5758" }, { "name": { "family": "Moore", "given": "Fred L." }, "orcid": "0000-0002-8461-2535" }, { "name": { "family": "Nicely", "given": "Julie M." }, "orcid": "0000-0003-4828-0032" }, { "name": { "family": "Peischl", "given": "Jeffrey" }, "orcid": "0000-0002-9320-7101" }, { "name": { "family": "Ryerson", "given": "Thomas B." }, "orcid": "0000-0003-2800-7581" }, { "name": { "family": "St. Clair", "given": "Jason M." }, "orcid": "0000-0002-9367-5749" }, { "name": { "family": "Sweeney", "given": "Colm" }, "orcid": "0000-0001-9568-0050" }, { "id": "Teng-Alex-P", "name": { "family": "Teng", "given": "Alex" } }, { "name": { "family": "Thompson", "given": "Chelsea R." }, "orcid": "0000-0002-7332-9945" }, { "name": { "family": "Ullmann", "given": "Kirk" }, "orcid": "0000-0002-4724-9634" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" }, { "name": { "family": "Wolfe", "given": "Glenn M." }, "orcid": "0000-0001-6586-4043" } ] }, "title": "Missing OH reactivity in the global marine boundary layer", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2020 The Author(s). This work is distributed under the Creative Commons Attribution 4.0 License. Published by Copernicus Publications on behalf of the European Geosciences Union. \n\nReceived: 24 Sep 2019 \u2013 Discussion started: 16 Oct 2019 \u2013 Revised: 30 Jan 2020 \u2013 Accepted: 02 Mar 2020 \u2013 Published: 02 Apr 2020. \n\nThe authors thank the NASA ATom management team, pilots, logistical support team, aircraft operations team, and fellow scientists. We thank the reviewers for their helpful comments on the initial submission. \n\nData availability. The data and model used in this paper are publicly available: data: https://doi.org/10.3334/ORNLDAAC/1581 (Wofsy et al., 2018); model framework: https://github.com/airchem/F0AM (last access: 12 July 2019); and MCMv331 chemical mechanism: http://mcm.leeds.ac.uk/MCM/ (Rickard et al., 1997). \n\nAuthor contributions. ABT, DOM, and WHB made the OH, HO2, and OH reactivity measurements; performed the model runs; analyzed the data; and wrote the manuscript. GMW provided support of the use of the F0AM model framework used for the model runs. WHB, DOM, ABT, HMA, DRB, TPB, RC, JDC, BCD, GSD, JPD, JWE, SRH, TFH, RAH, EH, MJK, KM, FLM, JMN, JP, TBR, JMS, CS, APT, CT, KU, POW, and GMW provided ATom measurements used for the modeling and reviewed and edited the manuscript. \n\nThe authors declare that they have no conflict of interest. \n\nThis research has been supported by NASA (grant no. NNX15AG59A). This material is based upon work supported by the National Center for Atmospheric Research, which is a major facility sponsored by the National Science Foundation under cooperative agreement no. 1852977. \n\nReview statement. This paper was edited by Andreas Hofzumahaus and reviewed by two anonymous referees.\n\nPublished - acp-20-4013-2020.pdf
", "abstract": "The hydroxyl radical (OH) reacts with thousands of chemical species in the atmosphere, initiating their removal and the chemical reaction sequences that produce ozone, secondary aerosols, and gas-phase acids. OH reactivity, which is the inverse of OH lifetime, influences the OH abundance and the ability of OH to cleanse the atmosphere. The NASA Atmospheric Tomography (ATom) campaign used instruments on the NASA DC-8 aircraft to measure OH reactivity and more than 100 trace chemical species. ATom presented a unique opportunity to test the completeness of the OH reactivity calculated from the chemical species measurements by comparing it to the measured OH reactivity over two oceans across four seasons. Although the calculated OH reactivity was below the limit of detection for the ATom instrument used to measure OH reactivity throughout much of the free troposphere, the instrument was able to measure the OH reactivity in and just above the marine boundary layer. The mean measured value of OH reactivity in the marine boundary layer across all latitudes and all ATom deployments was 1.9\u2009s\u207b\u00b9, which is 0.5\u2009s\u207b\u00b9 larger than the mean calculated OH reactivity. The missing OH reactivity, the difference between the measured and calculated OH reactivity, varied between 0 and 3.5\u2009s\u207b\u00b9, with the highest values over the Northern Hemisphere Pacific Ocean. Correlations of missing OH reactivity with formaldehyde, dimethyl sulfide, butanal, and sea surface temperature suggest the presence of unmeasured or unknown volatile organic compounds or oxygenated volatile organic compounds associated with ocean emissions.", "date": "2020-04-02", "date_type": "published", "publication": "Atmospheric Chemistry and Physics", "volume": "20", "number": "6", "publisher": "European Geosciences Union", "pagerange": "4013-4029", "id_number": "CaltechAUTHORS:20200417-110627301", "issn": "1680-7324", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200417-110627301", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NNX15AG59A" }, { "agency": "NSF", "grant_number": "AGS-1852977" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/acp-20-4013-2020", "primary_object": { "basename": "acp-20-4013-2020.pdf", "url": "https://authors.library.caltech.edu/records/16naj-hvh05/files/acp-20-4013-2020.pdf" }, "resource_type": "article", "pub_year": "2020", "author_list": "Thames, Alexander B.; Brune, William H.; et el." }, { "id": "https://authors.library.caltech.edu/records/ct2sc-f7m12", "eprint_id": 102224, "eprint_status": "archive", "datestamp": "2023-08-22 04:14:01", "lastmod": "2023-10-23 16:20:38", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Yin-Yi", "name": { "family": "Yin", "given": "Yi" }, "orcid": "0000-0003-4750-4997" }, { "id": "Byrne-B", "name": { "family": "Byrne", "given": "Brendan" }, "orcid": "0000-0003-0619-3045" }, { "id": "Liu-Junjie", "name": { "family": "Liu", "given": "Junjie" }, "orcid": "0000-0002-7184-6594" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Davis-K-J", "name": { "family": "Davis", "given": "Kenneth J." }, "orcid": "0000-0002-1992-8381" }, { "id": "Magney-T-S", "name": { "family": "Magney", "given": "Troy" }, "orcid": "0000-0002-9033-0024" }, { "id": "K\u00f6hler-P", "name": { "family": "K\u00f6hler", "given": "Philipp" }, "orcid": "0000-0002-7820-1318" }, { "id": "He-Liyin", "name": { "family": "He", "given": "Liyin" }, "orcid": "0000-0003-4427-1438" }, { "id": "Jeyaram-R", "name": { "family": "Jeyaram", "given": "Rupesh" } }, { "id": "Humphrey-V", "name": { "family": "Humphrey", "given": "Vincent" }, "orcid": "0000-0002-2541-6382" }, { "id": "Gerken-T", "name": { "family": "Gerken", "given": "Tobias" }, "orcid": "0000-0001-5617-186X" }, { "id": "Feng-Sha", "name": { "family": "Feng", "given": "Sha" }, "orcid": "0000-0002-2376-0868" }, { "id": "DiGangi-J-P", "name": { "family": "DiGangi", "given": "Joshua P." }, "orcid": "0000-0002-6764-8624" }, { "id": "Frankenberg-C", "name": { "family": "Frankenberg", "given": "Christian" }, "orcid": "0000-0002-0546-5857" } ] }, "title": "Cropland Carbon Uptake Delayed and Reduced by 2019 Midwest Floods", "ispublished": "pub", "full_text_status": "public", "keywords": "flood; crop; carbon cycle; SIF; TROPOM; OCO\u20102", "note": "\u00a9 2020 The Authors. This is an open access article under the terms of the Creative Commons Attribution\u2010NonCommercial License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited and is not used for commercial purposes. \n\nIssue Online: 25 March 2020; Version of Record online: 25 March 2020; Manuscript accepted: 05 February 2020; Manuscript revised: 03 February 2020; Manuscript received: 06 December 2019. \n\nPart of this research was funded by the NASA Carbon Cycle Science program (Grants NNX17AE14G and NNH16ZDA001N) and the NASA OCO\u20102 Science Team (Grants 80NSSC18K0895 and NNH17ZDA001N). TROPOMI SIF data generation by P. K. and C. F. is funded by the Earth Science U.S. Participating Investigator program (Grant NNX15AH95G). Aircraft data is funded by the Atmospheric Carbon and Transport (ACT)\u2010America Earth Venture Suborbital mission (grant NNX15AG76G to Penn State). B. B.'s research was supported by an appointment to the NASA Postdoctoral Program at the Jet Propulsion Laboratory, administered by Universities Space Research Association under contract with NASA. V.H. was supported by the Swiss National Science Foundation (P400P2_180784). Resources supporting this work were provided by the NASA High\u2010End Computing (HEC) Program through the NASA Advanced Supercomputing (NAS) Division at Ames Research Center. 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 (80NM0018D0004). \n\nData Availability Statement: TROPOMI and OCO\u20102 SIF products are accessed online (at https://data.caltech.edu/records/1347 (DOI: 10.22002/D1.1347) and https://oco2.gesdisc.eosdis.nasa.gov/data/OCO2_DATA/OCO2_L2_Lite_SIF.8r/). OCO\u20102 XCO2 retrieval files are downloaded from Jet Propulsion Laboratory (https://co2.jpl.nasa.gov/). ACT\u2010America L2 in situ measurements can be downloaded from the ORNL DACC (https://doi.org/10.3334/ORNLDAAC/1556). County\u2010level crop statistics is available at USDA NASS Quick Stats Database (https://quickstats.nass.usda.gov).\n\nPublished - 2019AV000140.pdf
Supplemental Material - aga20023-sup-0001-2019av000140-si.pdf
Supplemental Material - aga20023-sup-0003-2019av000140-peer_review_history.pdf
", "abstract": "While large\u2010scale floods directly impact human lives and infrastructures, they also profoundly impact agricultural productivity. New satellite observations of vegetation activity and atmospheric CO\u2082 offer the opportunity to quantify the effects of such extreme events on cropland carbon sequestration. Widespread flooding during spring and early summer 2019 induced conditions that delayed crop planting across the U.S. Midwest. As a result, satellite observations of solar\u2010induced chlorophyll fluorescence from TROPOspheric Monitoring Instrument and Orbiting Carbon Observatory reveal a 16\u2010day shift in the seasonal cycle of photosynthesis relative to 2018, along with a 15% lower peak value. We estimate a reduction of 0.21 PgC in cropland gross primary productivity in June and July, partially compensated in August and September (+0.14 PgC). The extension of the 2019 growing season into late September is likely to have benefited from increased water availability and late\u2010season temperature. Ultimately, this change is predicted to reduce the crop productivity in the Midwest Corn/Soy belt by ~15% compared to 2018. Using an atmospheric transport model, we show that a decline of ~0.1 PgC in the net carbon uptake during June and July is consistent with observed CO\u2082 enhancements of up to 10 ppm in the midday boundary layer from Atmospheric Carbon and Transport\u2010America aircraft and over 3 ppm in column\u2010averaged dry\u2010air mole fractions from Orbiting Carbon Observatory. This study quantifies the impact of floods on cropland productivity and demonstrates the potential of combining solar\u2010induced chlorophyll fluorescence with atmospheric CO\u2082 observations to monitor regional carbon flux anomalies.", "date": "2020-03", "date_type": "published", "publication": "AGU Advances", "volume": "1", "number": "1", "publisher": "American Geophysical Union", "pagerange": "Art. No. e2019AV000140", "id_number": "CaltechAUTHORS:20200401-082833885", "issn": "2576-604X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200401-082833885", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NNX17AE14G" }, { "agency": "NASA", "grant_number": "NNH16ZDA001N" }, { "agency": "NASA", "grant_number": "80NSSC18K0895" }, { "agency": "NASA", "grant_number": "NNH17ZDA001N" }, { "agency": "NASA", "grant_number": "NNX15AH95G" }, { "agency": "NASA", "grant_number": "NNX15AG76G" }, { "agency": "NASA Postdoctoral Program" }, { "agency": "Swiss National Science Foundation (SNSF)", "grant_number": "P400P2_180784" }, { "agency": "NASA", "grant_number": "80NM0018D0004" }, { "agency": "NASA/JPL/Caltech" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2019av000140", "primary_object": { "basename": "2019AV000140.pdf", "url": "https://authors.library.caltech.edu/records/ct2sc-f7m12/files/2019AV000140.pdf" }, "related_objects": [ { "basename": "aga20023-sup-0001-2019av000140-si.pdf", "url": "https://authors.library.caltech.edu/records/ct2sc-f7m12/files/aga20023-sup-0001-2019av000140-si.pdf" }, { "basename": "aga20023-sup-0003-2019av000140-peer_review_history.pdf", "url": "https://authors.library.caltech.edu/records/ct2sc-f7m12/files/aga20023-sup-0003-2019av000140-peer_review_history.pdf" } ], "resource_type": "article", "pub_year": "2020", "author_list": "Yin, Yi; Byrne, Brendan; et el." }, { "id": "https://authors.library.caltech.edu/records/h7xm7-qq626", "eprint_id": 100469, "eprint_status": "archive", "datestamp": "2023-08-22 03:39:25", "lastmod": "2023-10-23 16:12:18", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Brune-W-H", "name": { "family": "Brune", "given": "W. H." }, "orcid": "0000-0002-1609-4051" }, { "id": "Allen-H-M", "name": { "family": "Allen", "given": "H. M." } }, { "id": "Crounse-J-D", "name": { "family": "Crounse", "given": "J. D." }, "orcid": "0000-0001-5443-729X" }, { "id": "Kim-M-J", "name": { "family": "Kim", "given": "M. J." } }, { "id": "Teng-Alex-P", "name": { "family": "Teng", "given": "A. P." } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "Exploring Oxidation in the Remote Free Troposphere: Insights from Atmospheric Tomography (ATom)", "ispublished": "pub", "full_text_status": "public", "keywords": "hydroxyl; atmospheric chemistry; remote troposphere", "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 17 SEP 2019; Accepted 19 DEC 2019; Accepted article online 27 DEC 2019. \n\nThe authors thank the NASA ATom management team, pilots, logistical support team, aircraft operations team, and fellow scientists. \n\nData and Model Availability: The data and model used in this paper are publicly available: data: https://doi.org/10.3334/ORNLDAAC/1581; model framework: https://sites.google.com/site/wolfegm/models; MCMv331 chemical mechanism: http://mcm.leeds.ac.uk/MCM/. \n\nAuthor Contribution: DOM, WHB, and ABT made the OH and HO2 measurements, performed the model runs, analyzed the data, and wrote the initial draft of the manuscript. GMW provided support the F0AM model framework. WHB, DOM, ABT, HMA, ECA. DRB, TPB, RC, JDC, BCD, GSD, JPD, JWE, SRH, TFH, RAH, EJH, RSH, MJK, KM, FLM, JMN, JAN, JP, TBR, JMS CS., APT, CT, KU, PRV, POW, GMW provided ATom measurements used for the modeling and edits for the manuscript. \n\nThe authors declare no financial or affiliation conflicts-of-interest. \n\nThis study was supported by the NASA grant NNX15AG59A. This material is based upon work supported by the National Center for Atmospheric Research, which is a major facility sponsored by the National Science Foundation under Cooperative Agreement No. 1852977. MJK was supported by NSF fellowship 1524860 for the first year of this study.\n\nPublished - Brune_et_al-2020-Journal_of_Geophysical_Research__Atmospheres.pdf
Supplemental Material - jgrd55975-sup-0001-2019jd031685-si.pdf
", "abstract": "Earth's atmosphere oxidizes the greenhouse gas methane and other gases, thus determining their lifetimes and oxidation products. Much of this oxidation occurs in the remote, relatively clean free troposphere above the planetary boundary layer, where the oxidation chemistry is thought to be much simpler and better understood than it is in urban regions or forests. The NASA airborne Atmospheric Tomography study (ATom) was designed to produce cross sections of the detailed atmospheric composition in the remote atmosphere over the Pacific and Atlantic Oceans during four seasons. As part of the extensive ATom data set, measurements of the atmosphere's primary oxidant, hydroxyl (OH), and hydroperoxyl (HO\u2082) are compared to a photochemical box model to test the oxidation chemistry. Generally, observed and modeled median OH and HO\u2082 agree to with combined uncertainties at the 2\u03c3 confidence level, which is ~\u00b140%. For some seasons, this agreement is within ~\u00b120% below 6 km altitude. While this test finds no significant differences, OH observations increasingly exceeded modeled values at altitudes above 8 km, becoming ~35% greater, which is near the combined uncertainties. Measurement uncertainty and possible unknown measurement errors complicate tests for unknown chemistry or incorrect reaction rate coefficients that would substantially affect the OH and HO\u2082 abundances. Future analysis of detailed comparisons may yield additional discrepancies that are masked in the median values.", "date": "2020-01-16", "date_type": "published", "publication": "Journal of Geophysical Research. Atmospheres", "volume": "125", "number": "1", "publisher": "American Geophysical Union", "pagerange": "Art. No. e2019JD031685", "id_number": "CaltechAUTHORS:20200102-145133388", "issn": "2169-897X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200102-145133388", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NNX15AG59A" }, { "agency": "National Center for Atmospheric Research (NCAR)" }, { "agency": "NSF", "grant_number": "AGS-1852977" }, { "agency": "NSF Postdoctoral Fellowship", "grant_number": "AGS-1524860" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2019jd031685", "primary_object": { "basename": "jgrd55975-sup-0001-2019jd031685-si.pdf", "url": "https://authors.library.caltech.edu/records/h7xm7-qq626/files/jgrd55975-sup-0001-2019jd031685-si.pdf" }, "related_objects": [ { "basename": "Brune_et_al-2020-Journal_of_Geophysical_Research__Atmospheres.pdf", "url": "https://authors.library.caltech.edu/records/h7xm7-qq626/files/Brune_et_al-2020-Journal_of_Geophysical_Research__Atmospheres.pdf" } ], "resource_type": "article", "pub_year": "2020", "author_list": "Brune, W. H.; Allen, H. M.; et el." }, { "id": "https://authors.library.caltech.edu/records/ha7x2-6ez89", "eprint_id": 101270, "eprint_status": "archive", "datestamp": "2023-08-22 03:36:34", "lastmod": "2023-10-19 22:35:16", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Schroeder-J-R", "name": { "family": "Schroeder", "given": "Jason R." } }, { "id": "Crawford-J-H", "name": { "family": "Crawford", "given": "James H." } }, { "id": "Ahn-Joon-Young", "name": { "family": "Ahn", "given": "Joon-Young" } }, { "id": "Chang-Limseok", "name": { "family": "Chang", "given": "Limseok" } }, { "id": "Fried-A", "name": { "family": "Fried", "given": "Alan" } }, { "id": "Walega-J", "name": { "family": "Walega", "given": "James" } }, { "id": "Weinheimer-A-J", "name": { "family": "Weinheimer", "given": "Andrew" }, "orcid": "0000-0001-6175-8286" }, { "id": "Montzka-D-D", "name": { "family": "Montzka", "given": "Denise D." } }, { "id": "Hall-S-R", "name": { "family": "Hall", "given": "Samuel R." }, "orcid": "0000-0002-2060-7112" }, { "id": "Ullmann-K", "name": { "family": "Ullmann", "given": "Kirk" }, "orcid": "0000-0002-4724-9634" }, { "id": "Wisthaler-A", "name": { "family": "Wisthaler", "given": "Armin" } }, { "id": "Mikoviny-T", "name": { "family": "Mikoviny", "given": "Tomas" } }, { "id": "Chen-Gao", "name": { "family": "Chen", "given": "Gao" } }, { "id": "Blake-D-R", "name": { "family": "Blake", "given": "Donald R." } }, { "id": "Blake-N-J", "name": { "family": "Blake", "given": "Nicola J." } }, { "id": "Hughes-S-C", "name": { "family": "Hughes", "given": "Stacey C." } }, { "id": "Meinardi-S", "name": { "family": "Meinardi", "given": "Simone" } }, { "id": "Diskin-G-S", "name": { "family": "Diskin", "given": "Glenn" }, "orcid": "0000-0002-3617-0269" }, { "id": "DiGangi-J-P", "name": { "family": "DiGangi", "given": "Joshua P." }, "orcid": "0000-0002-6764-8624" }, { "id": "Choi-Yonghoon", "name": { "family": "Choi", "given": "Yonghoon" }, "orcid": "0000-0001-6529-4722" }, { "id": "Pusede-S-E", "name": { "family": "Pusede", "given": "Sally E." } }, { "id": "Huey-G-L", "name": { "family": "Huey", "given": "Greg L." } }, { "id": "Tanner-D-J", "name": { "family": "Tanner", "given": "David J." } }, { "id": "Kim-Michelle-J", "name": { "family": "Kim", "given": "Michelle" }, "orcid": "0000-0002-4922-4334" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul" }, "orcid": "0000-0002-6126-3854" } ] }, "title": "Observation-based modeling of ozone chemistry in the Seoul metropolitan area during the Korea-United States Air Quality Study (KORUS-AQ)", "ispublished": "pub", "full_text_status": "public", "keywords": "Ozone, Air quality, Photochemistry, Korea, Seoul", "note": "\u00a9 2020 The Author(s). This is an open-access article distributed under the terms of the Creative Commons Attribution 4.0 International License (CC-BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. See http://creativecommons.org/licenses/by/4.0/. \n\nSubmitted: 03 May 2019; Accepted: 16 November 2019; Published: 13 January 2020. \n\nThe KORUS-AQ study was jointly funded by NASA and the Korean National Institute of Environmental Research (NIER). Special thanks goes to all who made the DC-8 flights over Seoul and in Korean airspace possible. This includes civil and military air traffic coordinators, DC-8 pilots and crew, and the scientists who negotiated the flight paths and permissions needed to collect these observations. The members of the PTR-MS instrument team (P. Eichler, L. Kaser, M. M\u00fcller) are acknowledged for their support with instrument preparation and field work. \n\nData Accessibility Statement: Outputs from all box model simulations used in this work are available on the KORUS-AQ archive: https://www-air.larc.nasa.gov/cgi-bin/ArcView/korusaq?MODEL=1. \n\nPTR-ToF-MS measurements aboard the NASA DC-8 during KORUS-AQ were supported by the Austrian Federal Ministry for Transport, Innovation and Technology (bmvit) through the Austrian Space Applications Programme (ASAP) of the Austrian Research Promotion Agency (FFG). \n\nThe authors have no competing interests to declare. \n\nAuthor contributions: Contributed to conception and design: JRS and JHC. Contributed to acquisition of data: all authors. Contributed to analysis and interpretation of data: JRS and JHC. Drafted, revised, and approved of manuscript for submission: JRS and JHC.\n\nPublished - 400-6906-1-PB.pdf
", "abstract": "The Seoul Metropolitan Area (SMA) has a population of 24 million and frequently experiences unhealthy levels of ozone (O\u2083). In this work, measurements taken during the Korea-United States Air Quality Study (KORUS-AQ, 2016) are used to explore regional gradients in O\u2083 and its chemical precursors, and an observationally-constrained 0-D photochemical box model is used to quantify key aspects of O\u2083 production including its sensitivity to precursor gases. Box model performance was evaluated by comparing modeled concentrations of select secondary species to airborne measurements. These comparisons indicate that the steady state assumption used in 0-D box models cannot describe select intermediate species, highlighting the importance of having a broad suite of trace gases as model constraints. When fully constrained, aggregated statistics of modeled O\u2083 production rates agreed with observed changes in O\u2083, indicating that the box model was able to represent the majority of O\u2083 chemistry.\nComparison of airborne observations between urban Seoul and a downwind receptor site reveal a positive gradient in O\u2083 coinciding with a negative gradient in NO_x, no gradient in CH\u2082O, and a slight positive gradient in modeled rates of O\u2083 production. Together, these observations indicate a radical-limited (VOC-limited) O\u2083 production environment in the SMA. Zero-out simulations identified C\u2087\u208a aromatics as the dominant VOC contributors to O\u2083 production, with isoprene and anthropogenic alkenes making smaller but appreciable contributions. Simulations of model sensitivity to decreases in NO_x produced results that were not spatially uniform, with large increases in O\u2083 production predicted for urban Seoul and decreases in O\u2083 production predicted for far-outlying areas. The policy implications of this work are clear: Effective O\u2083 mitigation strategies in the SMA must focus on reducing local emissions of C\u2087\u208a aromatics, while reductions in NO_x emissions may increase O\u2083 in some areas but generally decrease the regional extent of O\u2083 exposure.", "date": "2020-01-13", "date_type": "published", "publication": "Elementa: Science of the Anthropocene", "volume": "8", "number": "1", "publisher": "University of California Press", "id_number": "CaltechAUTHORS:20200213-104217327", "issn": "2325-1026", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200213-104217327", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA" }, { "agency": "Korean National Institute of Environmental Research" }, { "agency": "Bundesministerium f\u00fcr Verkehr, Innovation und Technologie (BMVIT)" }, { "agency": "Austrian Research Promotion Agency (FFG)" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1525/elementa.400", "primary_object": { "basename": "400-6906-1-PB.pdf", "url": "https://authors.library.caltech.edu/records/ha7x2-6ez89/files/400-6906-1-PB.pdf" }, "resource_type": "article", "pub_year": "2020", "author_list": "Schroeder, Jason R.; Crawford, James H.; et el." }, { "id": "https://authors.library.caltech.edu/records/ahwzn-vr377", "eprint_id": 98824, "eprint_status": "archive", "datestamp": "2023-08-22 02:43:53", "lastmod": "2023-10-18 17:39:58", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "M\u00f8ller-K-H", "name": { "family": "M\u00f8ller", "given": "Kristian H." }, "orcid": "0000-0001-8070-8516" }, { "id": "Praske-E", "name": { "family": "Praske", "given": "Eric" }, "orcid": "0000-0001-7169-4423" }, { "id": "Xu-Lu", "name": { "family": "Xu", "given": "Lu" }, "orcid": "0000-0002-0021-9876" }, { "id": "Crounse-J-D", "name": { "family": "Crounse", "given": "John D." }, "orcid": "0000-0001-5443-729X" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Kjaergaard-H-G", "name": { "family": "Kjaergaard", "given": "Henrik G." }, "orcid": "0000-0002-7275-8297" } ] }, "title": "Stereoselectivity in Atmospheric Autoxidation", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2019 American Chemical Society. \n\nReceived: July 8, 2019; Accepted: September 23, 2019; Published: September 23, 2019. \n\nAll \u03c9B97X-D/aug-cc-pVTZ and F12 output files, which include the \u03c9B97X-D/aug-cc-pVTZ optimized geometries are available at https://sid.erda.dk/public/archives/bfad8e9ca7cf171e6d225371b36c3372/published-archive.html. \n\nThe authors thank Hannah M. Allen for helpful discussions. K.H.M. acknowledges the financial support of the Danish Ministry for Higher Education and Science's Elite Research travel grant and the Niels Bohr Foundation. We are grateful for the funding from the National Science Foundation (Grant CHE-1508526), the Alfred P. Sloan Foundation's program Chemistry of Indoor Environments, the Independent Research Fund Denmark, and the University of Copenhagen. \n\nThe authors declare no competing financial interest.\n\nSupplemental Material - jz9b01972_si_001.pdf
", "abstract": "We show that the diastereomers of hydroxy peroxy radicals formed from OH and O_2 addition to C2 and C3, respectively, of crotonaldehyde (CH_3CHCHCHO) undergo gas-phase unimolecular aldehydic hydrogen shift (H-shift) chemistry with rate coefficients that differ by an order of magnitude. The stereospecificity observed here for crotonaldehyde is general and will lead to a significant diastereomeric-specific chemistry in the atmosphere. This enhancement of specific stereoisomers by stereoselective gas-phase reactions could have widespread implications given the ubiquity of chirality in nature. The H-shift rate coefficients calculated using multiconformer transition state theory (MC-TST) agree with those determined experimentally using stereoisomer-specific gas-chromatography chemical ionization mass spectroscopy (GC\u2013CIMS) measurements.", "date": "2019-10-17", "date_type": "published", "publication": "Journal of Physical Chemistry Letters", "volume": "10", "number": "20", "publisher": "American Chemical Society", "pagerange": "6260-6266", "id_number": "CaltechAUTHORS:20190924-092009258", "issn": "1948-7185", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190924-092009258", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Ministry of Higher Education and Science (Denmark)" }, { "agency": "Niels Bohr Foundation" }, { "agency": "NSF", "grant_number": "CHE-1508526" }, { "agency": "Alfred P. Sloan Foundation" }, { "agency": "Independent Research Fund Denmark" }, { "agency": "University of Copenhagen" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1021/acs.jpclett.9b01972", "primary_object": { "basename": "jz9b01972_si_001.pdf", "url": "https://authors.library.caltech.edu/records/ahwzn-vr377/files/jz9b01972_si_001.pdf" }, "resource_type": "article", "pub_year": "2019", "author_list": "M\u00f8ller, Kristian H.; Praske, Eric; et el." }, { "id": "https://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.edu/records/ttck5-4nd44", "eprint_id": 95622, "eprint_status": "archive", "datestamp": "2023-08-22 01:47:12", "lastmod": "2023-10-23 16:09:31", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Wolfe-Glenn-M", "name": { "family": "Wolfe", "given": "Glenn M." }, "orcid": "0000-0001-6586-4043" }, { "id": "Nicely-Julie-M", "name": { "family": "Nicely", "given": "Julie M." }, "orcid": "0000-0003-4828-0032" }, { "id": "St-Clair-Jason-M", "name": { "family": "St. Clair", "given": "Jason M." }, "orcid": "0000-0002-9367-5749" }, { "id": "Hanisco-Thomas-F", "name": { "family": "Hanisco", "given": "Thomas F." }, "orcid": "0000-0001-9434-8507" }, { "id": "Liao-Jin", "name": { "family": "Liao", "given": "Jin" } }, { "id": "Oman-Luke-D", "name": { "family": "Oman", "given": "Luke D." }, "orcid": "0000-0002-5487-2598" }, { "id": "Brune-William-B", "name": { "family": "Brune", "given": "William B." } }, { "id": "Miller-David-O", "name": { "family": "Miller", "given": "David" } }, { "id": "Thames-Alexander-B", "name": { "family": "Thames", "given": "Alexander" } }, { "id": "Gonz\u00e1lez-Abad-Gonzalo", "name": { "family": "Gonz\u00e1lez Abad", "given": "Gonzalo" }, "orcid": "0000-0002-8090-6480" }, { "id": "Ryerson-Thomas-B", "name": { "family": "Ryerson", "given": "Thomas B." }, "orcid": "0000-0003-2800-7581" }, { "id": "Thompson-Chelsea-R", "name": { "family": "Thompson", "given": "Chelsea R." }, "orcid": "0000-0002-7332-9945" }, { "id": "Peischl-Jeff", "name": { "family": "Peischl", "given": "Jeff" }, "orcid": "0000-0002-9320-7101" }, { "id": "McKain-Kathryn", "name": { "family": "McKain", "given": "Kathryn" } }, { "id": "Sweeney-Colm", "name": { "family": "Sweeney", "given": "Colm" }, "orcid": "0000-0001-9568-0050" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Kim-Michelle-J", "name": { "family": "Kim", "given": "Michelle" }, "orcid": "0000-0002-4922-4334" }, { "id": "Crounse-John-D", "name": { "family": "Crounse", "given": "John D." }, "orcid": "0000-0001-5443-729X" }, { "id": "Hall-Samuel-R", "name": { "family": "Hall", "given": "Samuel R." }, "orcid": "0000-0002-2060-7112" }, { "id": "Ullmann-Kirk", "name": { "family": "Ullmann", "given": "Kirk" }, "orcid": "0000-0002-4724-9634" }, { "id": "Diskin-Glenn-S", "name": { "family": "Diskin", "given": "Glenn" }, "orcid": "0000-0002-3617-0269" }, { "id": "Bui-Paul", "name": { "family": "Bui", "given": "Paul" }, "orcid": "0000-0001-9189-0405" }, { "id": "Chang-Cecilia", "name": { "family": "Chang", "given": "Cecilia" } }, { "id": "Dean-Day-Jonathan-M", "name": { "family": "Dean-Day", "given": "Jonathan" }, "orcid": "0000-0003-2621-5774" } ] }, "title": "Mapping hydroxyl variability throughout the global remote troposphere via synthesis of airborne and satellite formaldehyde observations", "ispublished": "pub", "full_text_status": "public", "keywords": "hydroxyl; formaldehyde; ATom; OMI; troposphere", "note": "\u00a9 2019 National Academy of Sciences. Published under the PNAS license. \n\nEdited by Mark H. Thiemens, University of California, San Diego, La Jolla, CA, and approved April 22, 2019 (received for review December 19, 2018). \n\nWe thank all of the NASA pilots, crew, logistical personnel, and science leadership who facilitated the ATom mission. We thank Clare Flynn for assembling the merged dataset used to constrain 0-D box model simulations, and we also thank the many scientists contributing observations to this dataset. We thank Can Li, Joanna Joiner, Arlene Fiore, and Colleen Baublitz for helpful discussions and feedback. This work was supported by the NASA ATom Earth Venture Suborbital-2 Program. The NASA Goddard Space Flight Center (GSFC) team acknowledges support from Atmospheric Composition Campaign Data Analysis and Modeling Grant NNX14AP48G, the NASA Upper Atmospheric Research Program, and the NASA Tropospheric Composition Program. J.M.N. was also supported by an appointment to the NASA Postdoctoral Program at the NASA GSFC, administered by the Universities Space Research Association under contract. OMI HCHO columns were developed with NASA support from Atmospheric Composition Modeling and Analysis Grant NNX17AH47G and the Aura Science Team. The Modern-Era Retrospective Analysis for Research and Applications 2 GMI simulation was supported by the NASA Modeling, Analysis, and Prediction Program and computational resources from the NASA Center for Climate Simulation. M.K. was funded by NSF Atmospheric and Geospace Sciences Postdoctoral Research Fellowship 1524860. Finally, we thank three anonymous reviewers for their expert critique of the manuscript. \n\nAuthor contributions: G.M.W. and J.M.N. designed research; G.M.W., J.M.N., T.F.H., L.D.O., W.B.B., D.M., A.T., G.G.A., T.B.R., C.R.T., J.P., K.M., C.S., P.O.W., M.K., J.D.C., S.R.H., K.U., G.D., P.B., and C.C. performed research; G.M.W., J.M.N., J.M.S.C., J.L., and J.D.-D. analyzed data; G.M.W. wrote the paper; G.M.W., J.M.S.C., T.F.H., W.B.B., D.M., A.T., T.B.R., C.R.T., J.P., K.M., C.S., P.O.W., M.K., J.D.C., S.R.H., K.U., G.D., P.B., C.C., and J.D.-D. contributed to ATom observations; L.D.O. provided GMI model output; and G.G.A. provided OMI retrievals. \n\nThe authors declare no conflict of interest. \n\nThis article is a PNAS Direct Submission. \n\nData deposition: The data reported in this paper have been deposited in the Oak Ridge National Laboratory (https://daac.ornl.gov/cgi-bin/dsviewer.pl?ds_id=1669). \n\nThis article contains supporting information online at www.pnas.org/lookup/suppl/doi:10.1073/pnas.1821661116/-/DCSupplemental.\n\nThe authors note that the author name Kathryn McCain should instead appear as Kathryn McKain. The corrected author line appears below. The online version has been corrected.\n\nPublished - 11171.full.pdf
Supplemental Material - pnas.1821661116.sapp.pdf
Erratum - pnas.201908931.pdf
", "abstract": "The hydroxyl radical (OH) fuels tropospheric ozone production and governs the lifetime of methane and many other gases. Existing methods to quantify global OH are limited to annual and global-to-hemispheric averages. Finer resolution is essential for isolating model deficiencies and building process-level understanding. In situ observations from the Atmospheric Tomography (ATom) mission demonstrate that remote tropospheric OH is tightly coupled to the production and loss of formaldehyde (HCHO), a major hydrocarbon oxidation product. Synthesis of this relationship with satellite-based HCHO retrievals and model-derived HCHO loss frequencies yields a map of total-column OH abundance throughout the remote troposphere (up to 70% of tropospheric mass) over the first two ATom missions (August 2016 and February 2017). This dataset offers unique insights on near-global oxidizing capacity. OH exhibits significant seasonality within individual hemispheres, but the domain mean concentration is nearly identical for both seasons (1.03 \u00b1 0.25 \u00d7 10^6 cm^(\u22123)), and the biseasonal average North/South Hemisphere ratio is 0.89 \u00b1 0.06, consistent with a balance of OH sources and sinks across the remote troposphere. Regional phenomena are also highlighted, such as a 10-fold OH depression in the Tropical West Pacific and enhancements in the East Pacific and South Atlantic. This method is complementary to budget-based global OH constraints and can help elucidate the spatial and temporal variability of OH production and methane loss.", "date": "2019-06-04", "date_type": "published", "publication": "Proceedings of the National Academy of Sciences of the United States of America", "volume": "116", "number": "23", "publisher": "National Academy of Sciences", "pagerange": "11171-11180", "id_number": "CaltechAUTHORS:20190521-075102186", "issn": "0027-8424", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190521-075102186", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NNX14AP48G" }, { "agency": "NASA Postdoctoral Program" }, { "agency": "NASA", "grant_number": "NNX17AH47G" }, { "agency": "NSF", "grant_number": "AGS-1524860" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1073/pnas.1821661116", "pmcid": "PMC6561255", "primary_object": { "basename": "11171.full.pdf", "url": "https://authors.library.caltech.edu/records/ttck5-4nd44/files/11171.full.pdf" }, "related_objects": [ { "basename": "pnas.1821661116.sapp.pdf", "url": "https://authors.library.caltech.edu/records/ttck5-4nd44/files/pnas.1821661116.sapp.pdf" }, { "basename": "pnas.201908931.pdf", "url": "https://authors.library.caltech.edu/records/ttck5-4nd44/files/pnas.201908931.pdf" } ], "resource_type": "article", "pub_year": "2019", "author_list": "Wolfe, Glenn M.; Nicely, Julie M.; et el." }, { "id": "https://authors.library.caltech.edu/records/13yjh-10t77", "eprint_id": 95069, "eprint_status": "archive", "datestamp": "2023-08-22 01:38:08", "lastmod": "2023-10-20 18:31:47", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Wang-Siyuan", "name": { "family": "Wang", "given": "Siyuan" }, "orcid": "0000-0002-8110-5714" }, { "id": "Crounse-John-D", "name": { "family": "Crounse", "given": "John D." }, "orcid": "0000-0001-5443-729X" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "Atmospheric Acetaldehyde: Importance of Air-Sea Exchange and a Missing Source in the Remote Troposphere", "ispublished": "pub", "full_text_status": "public", "keywords": "acetaldehyde; oxidative capacity; air\u2010sea exchange; ocean biogeochemistry; chemistry climate model", "note": "\u00a9 2019 American Geophysical Union. \n\nAccepted 18 APR 2019; Accepted article online 29 APR 2019; Published online 28 MAY 2019. \n\nThe Atmospheric Tomography Mission (ATom) is funded by the Earth Science Project Office at NASA (NNX15AJ23G, NNX15AH33A, NNX15AG70A, NNX15AG61A, NNX15AG71A, NNH15AB12I, NNX15AJ91A). ATom data are publicly available at https://espo.nasa.gov/atom as well as Wofsy et al. (2018). S.\u2010Y. W. is supported by the NCAR Advanced Study Program (ASP) Postdoctoral Fellowship. We thank NASA ESPO, the NASA DC\u20108 crew, and the ATom Science Team for their exceptional professionalism in support of this mission. Alex Thames, David Miller, and William H. Brune (Pennsylvania State University) are acknowledged for the HOx measurements. Charles Brock, Christina Williamson, Agnieszka Kupc, and Karl Froyd (Earth System Research Laboratory/Chemical Science Division/National Ocean and Atmospheric Administration) are acknowledged for the condensation and optically based particle counters. Kathryn McKain and Colm Sweeney (Earth System Research Laboratory/Global Monitoring Division/National Ocean and Atmospheric Administration) are acknowledged for the methane and carbon monoxide measurements. Glenn S. Diskin and Joshua P. DiGangi are acknowledged for the Diode Laser Hygrometer measurements of water vapor. The CESM project is supported primarily by the National Science Foundation (NSF). This material is based upon work supported by the National Center for Atmospheric Research, which is a major facility sponsored by the NSF under Cooperative Agreement 1852977. Computing and data storage resources, including the Cheyenne supercomputer (doi:10.5065/D6RX99HX), were provided by the Computational and Information Systems Laboratory (CISL) at NCAR. We thank the Editor and two anonymous reviewers for their constructive comments and feedback, which helped us to improve the manuscript. The authors declare that they have no conflict of interest.\n\nPublished - Wang_et_al-2019-Geophysical_Research_Letters.pdf
Accepted Version - nihms-1536059.pdf
", "abstract": "We report airborne measurements of acetaldehyde (CH\u2083CHO) during the first and second deployments of the National Aeronautics and Space Administration (NASA) Atmospheric Tomography Mission (ATom). The budget of CH\u2083CHO is examined using the Community Atmospheric Model with chemistry (CAM\u2010chem), with a newly\u2010developed online air\u2010sea exchange module. The upper limit of the global ocean net emission of CH\u2083CHO is estimated to be 34 Tg a\u207b\u00b9 (42 Tg a\u207b\u00b9 if considering bubble\u2010mediated transfer), and the ocean impacts on tropospheric CH\u2083CHO are mostly confined to the marine boundary layer. Our analysis suggests that there is an unaccounted CH\u2083CHO source in the remote troposphere and that organic aerosols can only provide a fraction of this missing source. We propose that peroxyacetic acid (PAA) is an ideal indicator of the rapid CH\u2083CHO production in the remote troposphere. The higher\u2010than\u2010expected CH\u2083CHO measurements represent a missing sink of hydroxyl radicals (and halogen radical) in current chemistry\u2010climate models.", "date": "2019-05-28", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "46", "number": "10", "publisher": "American Geophysical Union", "pagerange": "5601-5613", "id_number": "CaltechAUTHORS:20190429-101828226", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190429-101828226", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NNX15AJ23G" }, { "agency": "NASA", "grant_number": "NNX15AH33A" }, { "agency": "NASA", "grant_number": "NNX15AG70A" }, { "agency": "NASA", "grant_number": "NNX15AG61A" }, { "agency": "NASA", "grant_number": "NNX15AG71A" }, { "agency": "NASA", "grant_number": "NNH15AB12I" }, { "agency": "NASA", "grant_number": "NNX15AJ91A" }, { "agency": "National Center for Atmospheric Research (NCAR)" }, { "agency": "NSF", "grant_number": "AGS-1852977" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2019GL082034", "pmcid": "PMC7325730", "primary_object": { "basename": "Wang_et_al-2019-Geophysical_Research_Letters.pdf", "url": "https://authors.library.caltech.edu/records/13yjh-10t77/files/Wang_et_al-2019-Geophysical_Research_Letters.pdf" }, "related_objects": [ { "basename": "nihms-1536059.pdf", "url": "https://authors.library.caltech.edu/records/13yjh-10t77/files/nihms-1536059.pdf" } ], "resource_type": "article", "pub_year": "2019", "author_list": "Wang, Siyuan; Crounse, John D.; et el." }, { "id": "https://authors.library.caltech.edu/records/t89t8-kvq69", "eprint_id": 98392, "eprint_status": "archive", "datestamp": "2023-08-22 01:23:26", "lastmod": "2023-10-18 17:19:32", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Kiel-M", "name": { "family": "Kiel", "given": "Matth\u00e4us" }, "orcid": "0000-0002-9784-962X" }, { "id": "O'Dell-C-W", "name": { "family": "O'Dell", "given": "Christopher W." } }, { "id": "Fisher-B-M", "name": { "family": "Fisher", "given": "Brendan" } }, { "id": "Eldering-A", "name": { "family": "Eldering", "given": "Annmarie" }, "orcid": "0000-0003-1080-9922" }, { "id": "Nassar-R", "name": { "family": "Nassar", "given": "Ray" }, "orcid": "0000-0001-6282-1611" }, { "id": "MacDonald-C-G", "name": { "family": "MacDonald", "given": "Cameron G." } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "How bias correction goes wrong: measurement of X_(CO_2) affected by erroneous surface pressure estimates", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 Author(s) 2019. This work is distributed under the Creative Commons Attribution 4.0 License. \n\nReceived: 05 Oct 2018 \u2013 Discussion started: 19 Nov 2018 \u2013 Revised: 21 Feb 2019 \u2013 Accepted: 21 Feb 2019 \u2013 Published: 12 Apr 2019. \n\nWe thank David Crisp for helpful discussions on the viewing geometry of the observatory. We thank Callum McCracken for contributing to Fig. 4. This work was financially supported by NASA's OCO-2 project (grant no. NNN12AA01C) and NASA's Carbon Cycle and Ecosystems research program (grant no. NNX17AE15G). \n\nData availability. All of the OCO-2 data products are publicly available through the NASA Goddard Earth Science Data and Information Services Center (GES DISC) for distribution and archiving (http://disc.sci.gsfc.nasa.gov/OCO-2; last access: 31 March 2019). TCCON data were obtained from the TCCON data archive hosted by CaltechDATA and are available from https://tccondata.org/ (last access: 31 March 2019). \n\nThe authors declare that they have no conflict of interest. \n\nEdited by: Christof Janssen. Reviewed by: Fran\u00e7ois-Marie Br\u00e9on and one anonymous referee.\n\nPublished - amt-12-2241-2019.pdf
", "abstract": "All measurements of X_(CO_2) from space have systematic errors. To reduce a large fraction of these errors, a bias correction is applied to X_(CO_2) retrieved from GOSAT and OCO-2 spectra using the ACOS retrieval algorithm. The bias correction uses, among other parameters, the surface pressure difference between the retrieval and the meteorological reanalysis. Relative errors in the surface pressure estimates, however, propagate nearly 1:1 into relative errors in bias-corrected X_(CO_2). For OCO-2, small errors in the knowledge of the pointing of the observatory (up to \u223c130\u2009arcsec) introduce a bias in X_(CO_2) in regions with rough topography. Erroneous surface pressure estimates are also caused by a coding error in ACOS version 8, sampling meteorological analyses at wrong times (up to 3\u2009h after the overpass time). Here, we derive new geolocations for OCO-2's eight footprints and show how using improved knowledge of surface pressure estimates in the bias correction reduces errors in OCO-2's v9 X_(CO_2) data.", "date": "2019-04-12", "date_type": "published", "publication": "Atmospheric Measurement Techniques", "volume": "12", "number": "4", "publisher": "European Geosciences Union", "pagerange": "2241-2259", "id_number": "CaltechAUTHORS:20190903-130240537", "issn": "1867-8548", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190903-130240537", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NNN12AA01C" }, { "agency": "NASA", "grant_number": "NNX17AE15G" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/amt-12-2241-2019", "primary_object": { "basename": "amt-12-2241-2019.pdf", "url": "https://authors.library.caltech.edu/records/t89t8-kvq69/files/amt-12-2241-2019.pdf" }, "resource_type": "article", "pub_year": "2019", "author_list": "Kiel, Matth\u00e4us; O'Dell, Christopher W.; et el." }, { "id": "https://authors.library.caltech.edu/records/r4fkh-9ej50", "eprint_id": 93220, "eprint_status": "archive", "datestamp": "2023-08-22 01:12:32", "lastmod": "2023-10-20 16:57:21", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Bianchi-Federico", "name": { "family": "Bianchi", "given": "Federico" }, "orcid": "0000-0003-2996-3604" }, { "id": "Kurt\u00e9n-Theo", "name": { "family": "Kurt\u00e9n", "given": "Theo" }, "orcid": "0000-0002-6416-4931" }, { "id": "Riva-Matthieu", "name": { "family": "Riva", "given": "Matthieu" } }, { "id": "Mohr-Claudia", "name": { "family": "Mohr", "given": "Claudia" } }, { "id": "Rissanen-Matti-P", "name": { "family": "Rissanen", "given": "Matti P." }, "orcid": "0000-0003-0463-8098" }, { "id": "Roldin-Pontus", "name": { "family": "Roldin", "given": "Pontus" } }, { "id": "Berndt-Torsten", "name": { "family": "Berndt", "given": "Torsten" }, "orcid": "0000-0003-2014-6018" }, { "id": "Crounse-John-D", "name": { "family": "Crounse", "given": "John D." }, "orcid": "0000-0001-5443-729X" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Mentel-Thomas-F", "name": { "family": "Mentel", "given": "Thomas F." } }, { "id": "Wildt-J\u00fcrgen", "name": { "family": "Wildt", "given": "J\u00fcrgen" } }, { "id": "Junninen-Heikki", "name": { "family": "Junninen", "given": "Heikki" } }, { "id": "Jokinen-Tuija", "name": { "family": "Jokinen", "given": "Tuija" } }, { "id": "Kulmala-Markku", "name": { "family": "Kulmala", "given": "Markku" } }, { "id": "Worsnop-Douglas-R", "name": { "family": "Worsnop", "given": "Douglas R." }, "orcid": "0000-0002-8928-8017" }, { "id": "Thornton-Joel-A", "name": { "family": "Thornton", "given": "Joel A." }, "orcid": "0000-0002-5098-4867" }, { "id": "Donahue-Neil", "name": { "family": "Donahue", "given": "Neil" }, "orcid": "0000-0003-3054-2364" }, { "id": "Kjaergaard-Henrik-G", "name": { "family": "Kjaergaard", "given": "Henrik G." }, "orcid": "0000-0002-7275-8297" }, { "id": "Ehn-Mikael", "name": { "family": "Ehn", "given": "Mikael" }, "orcid": "0000-0002-0215-4893" } ] }, "title": "Highly Oxygenated Molecules (HOM) from Gas-Phase Autoxidation Involving Organic Peroxy Radicals: A Key Contributor to Atmospheric Aerosol", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2019 American Chemical Society. ACS AuthorChoice - This is an open access article published under a Creative Commons Attribution (CC-BY) License, which permits unrestricted use, distribution and reproduction in any medium, provided the author and source are cited. \n\nReceived: June 25, 2018; Publication Date (Web): February 25, 2019. \n\nWe thank Ugo Molteni, Liine Heikkinen, Rasmus V. Otkj\u00e6r, and Kristian H. M\u00f8ller for useful discussion. We thank the CSC Centre for Scientific Computing in Finland and the Danish Center for Scientific Computing from the Copenhagen University. We also thank the Center for Exploitation of Solar Energy founded by the University of Copenhagen, the Swedish Strategic Research Program MERGE, and the European Regional Development Fund (project MOBTT42). This research has received funding from the Swiss National Science Foundation (P2EZP2_168787), the Academy of Finland (grant no. 1315203, 266388 and 299574), the U.S. National Science Foundation (grant nos. AGS 1801897, ACS 1508526), the U.S. Department of Energy's Office of Science (grant no. DE-SC0018221), and the European Research Council starting grant COALA (grant no. 638703). \n\nThe authors declare no competing financial interest.\n\nPublished - acs.chemrev.8b00395.pdf
", "abstract": "Highly oxygenated organic molecules (HOM) are formed in the atmosphere via autoxidation involving peroxy radicals arising from volatile organic compounds (VOC). HOM condense on pre-existing particles and can be involved in new particle formation. HOM thus contribute to the formation of secondary organic aerosol (SOA), a significant and ubiquitous component of atmospheric aerosol known to affect the Earth's radiation balance. HOM were discovered only very recently, but the interest in these compounds has grown rapidly. In this Review, we define HOM and describe the currently available techniques for their identification/quantification, followed by a summary of the current knowledge on their formation mechanisms and physicochemical properties. A main aim is to provide a common frame for the currently quite fragmented literature on HOM studies. Finally, we highlight the existing gaps in our understanding and suggest directions for future HOM research.", "date": "2019-03-27", "date_type": "published", "publication": "Chemical Reviews", "volume": "119", "number": "6", "publisher": "American Chemical Society", "pagerange": "3472-3509", "id_number": "CaltechAUTHORS:20190225-101818008", "issn": "0009-2665", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190225-101818008", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "European Regional Development Fund", "grant_number": "MOBTT42" }, { "agency": "Swiss National Science Foundation (SNSF)", "grant_number": "P2EZP2_168787" }, { "agency": "Academy of Finland", "grant_number": "131520" }, { "agency": "Academy of Finland", "grant_number": "266388" }, { "agency": "Academy of Finland", "grant_number": "299574" }, { "agency": "NSF", "grant_number": "AGS-1801897" }, { "agency": "NSF", "grant_number": "ACS-1508526" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0018221" }, { "agency": "European Research Council (ERC)", "grant_number": "638703" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1021/acs.chemrev.8b00395", "pmcid": "PMC6439441", "primary_object": { "basename": "acs.chemrev.8b00395.pdf", "url": "https://authors.library.caltech.edu/records/r4fkh-9ej50/files/acs.chemrev.8b00395.pdf" }, "resource_type": "article", "pub_year": "2019", "author_list": "Bianchi, Federico; Kurt\u00e9n, Theo; et el." }, { "id": "https://authors.library.caltech.edu/records/g35x5-91b72", "eprint_id": 92540, "eprint_status": "archive", "datestamp": "2023-08-22 00:57:57", "lastmod": "2023-10-20 15:49:41", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Xu-Lu", "name": { "family": "Xu", "given": "Lu" }, "orcid": "0000-0002-0021-9876" }, { "id": "M\u00f8ller-K-H", "name": { "family": "M\u00f8ller", "given": "Kristian H." }, "orcid": "0000-0001-8070-8516" }, { "id": "Crounse-J-D", "name": { "family": "Crounse", "given": "John D." }, "orcid": "0000-0001-5443-729X" }, { "id": "Otkj\u00e6r-R-V", "name": { "family": "Otkj\u00e6r", "given": "Rasmus V." }, "orcid": "0000-0002-6094-1828" }, { "id": "Kjaergaard-H-G", "name": { "family": "Kjaergaard", "given": "Henrik Grum" }, "orcid": "0000-0002-7275-8297" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "Unimolecular Reactions of Peroxy Radicals Formed in the Oxidation of \u03b1-pinene and \u03b2-pinene by Hydroxyl Radicals", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2019 American Chemical Society. \n\nReceived: December 5, 2018; Revised: January 30, 2019; Published: January 31, 2019. \n\nWe thank Eric Praske, Krystal T. Vasquez, and Yuanlong Huang for technical support. L.X., J.D.C., and P.O.W. acknowledge NASA (NNX14AP46G) and NSF (CHE-1508526) for support of this work. K.H.M., R.V.O., and H.G.K. acknowledge funding from the University of Copenhagen. K.H.M. acknowledges the financial support from the Danish Ministry for Higher Education and Science's Elite Research Travel Grant. \n\nThe authors declare no competing financial interest.\n\nSupplemental Material - jp8b11726_si_001.pdf
", "abstract": "Atmospheric oxidation of monoterpenes (emitted primarily by evergreen trees) is known to contribute to the formation and growth of aerosol particles. While recent research has tied the formation of organic aerosol to unimolecular chemistry of the organic peroxy radicals (RO_2) formed in the oxidation of monoterpenes, the fundamental physical chemistry of these RO_2 remains obscure. Here we use isomer-specific measurements and ab initio calculations to determine the unimolecular reaction rates and products of RO_2 derived from the hydroxyl radical (OH) oxidation of \u03b1-pinene and \u03b2-pinene. Among all of the structural isomers of the first-generation RO_2 from both monoterpenes, we find that the first-generation RO_2 produced following opening of the four-membered ring undergo fast unimolecular reactions (4 \u00b1 2 and 16 \u00b1 5 s^(\u20131) for \u03b1-pinene and \u03b2-pinene, respectively) at 296 K, in agreement with high-level ab initio calculations. The presence of the hydroxy group and carbon\u2013carbon double bond in the ring-opened RO_2 enhances the rates of these unimolecular reactions, including endo-cyclization and H-shift via transition states involving six- and seven-membered rings. These reaction rate coefficients are sufficiently large that unimolecular chemistry is the dominant fate of these monoterpene-derived RO_2 in the atmosphere. In addition, the overall yields of first-generation \u03b1-pinene and \u03b2-pinene hydroxy nitrates, C_(10)H_(17)NO_4, at 296 K and 745 Torr are measured to be 3.3 \u00b1 1.5% and 6.4 \u00b1 2.1%, respectively, for conditions where all RO_2 are expected to react with NO ([NO] > 1000 ppbv). These yields are lower than anticipated.", "date": "2019-02-28", "date_type": "published", "publication": "Journal of Physical Chemistry A", "volume": "123", "number": "8", "publisher": "American Chemical Society", "pagerange": "1661-1674", "id_number": "CaltechAUTHORS:20190131-104830327", "issn": "1089-5639", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190131-104830327", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NNX14AP46G" }, { "agency": "NSF", "grant_number": "CHE-1508526" }, { "agency": "University of Copenhagen" }, { "agency": "Ministry for Higher Education and Science (Denmark)" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1021/acs.jpca.8b11726", "primary_object": { "basename": "jp8b11726_si_001.pdf", "url": "https://authors.library.caltech.edu/records/g35x5-91b72/files/jp8b11726_si_001.pdf" }, "resource_type": "article", "pub_year": "2019", "author_list": "Xu, Lu; M\u00f8ller, Kristian H.; et el." }, { "id": "https://authors.library.caltech.edu/records/g74pq-te194", "eprint_id": 91848, "eprint_status": "archive", "datestamp": "2023-08-22 00:43:03", "lastmod": "2023-10-19 23:46:32", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Praske-E", "name": { "family": "Praske", "given": "Eric" }, "orcid": "0000-0001-7169-4423" }, { "id": "Otkj\u00e6r-R-V", "name": { "family": "Otkj\u00e6r", "given": "Rasmus V." }, "orcid": "0000-0002-6094-1828" }, { "id": "Crounse-J-D", "name": { "family": "Crounse", "given": "John D." }, "orcid": "0000-0001-5443-729X" }, { "id": "Hethcox-J-C", "name": { "family": "Hethcox", "given": "J. Caleb" }, "orcid": "0000-0002-7712-308X" }, { "id": "Stoltz-B-M", "name": { "family": "Stoltz", "given": "Brian M." }, "orcid": "0000-0001-9837-1528" }, { "id": "Kjaergaard-H-G", "name": { "family": "Kjaergaard", "given": "Henrik G." }, "orcid": "0000-0002-7275-8297" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "Intramolecular Hydrogen Shift Chemistry of Hydroperoxy-Substituted Peroxy Radicals", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2018 American Chemical Society. \n\nReceived: October 5, 2018; Revised: December 10, 2018;\nPublished: December 14, 2018.\n\nJ.C.H. thanks the Camille and Henry Dreyfus postdoctoral program in Environmental Chemistry for support. We acknowledge funding from the National Science Foundation (Grant CHE-1508526), the University of Copenhagen, and the Danish Center for Scientific Computing.\n\nThe authors declare no competing financial interest.\n\nThe wB97X-D/aug-cc-pVTZ optimizations and frequencies and the CCSD(T)-F12a/VDZ-F12 single point energy calculations are available at https://sid.erda.dk/public/archives/4f4b98346d6b007ba44411c642b39fa1/published-archive.html.\n\nSupplemental Material - jp8b09745_si_001.pdf
", "abstract": "Gas-phase autoxidation \u2013 the sequential regeneration of peroxy radicals (RO_2) via intramolecular hydrogen shifts (H-shifts) followed by oxygen addition \u2013 leads to the formation of organic hydroperoxides. The atmospheric fate of these peroxides remains unclear, including the potential for further H-shift chemistry. Here, we report H-shift rate coefficients for a system of RO_2 with hydroperoxide functionality produced in the OH-initiated oxidation of 2-hydroperoxy-2-methylpentane. The initial RO_2 formed in this chemistry are unable to undergo \u03b1-OOH H-shift (HOOC\u2013H) reactions. However, these RO_2 rapidly isomerize (>100 s^(\u20131) at 296 K) by H-shift of the hydroperoxy hydrogen (ROO\u2013H) to produce a hydroperoxy-substituted RO_2 with an accessible \u03b1-OOH hydrogen. First order rate coefficients for the 1,5 H-shift of the \u03b1-OOH hydrogen are measured to be \u223c0.04 s^(\u20131) (296 K) and \u223c0.1 s^(\u20131) (318 K), within 50% of the rate coefficients calculated using multiconformer transition state theory. Reaction of the RO_2 with NO produces alkoxy radicals which also undergo rapid isomerization via 1,6 and 1,5 H-shift of the hydroperoxy hydrogen (ROO\u2013H) to produce RO_2 with alcohol functionality. One of these hydroxy-substituted RO_2 exhibits a 1,5 \u03b1-OH (HOC\u2013H) H-shift, measured to be \u223c0.2 s^(\u20131) (296 K) and \u223c0.6 s^(\u20131) (318 K), again in agreement with the calculated rates. Thus, the rapid shift of hydroperoxy hydrogens in alkoxy and peroxy radicals enables intramolecular reactions that would otherwise be inaccessible.", "date": "2019-01-17", "date_type": "published", "publication": "Journal of Physical Chemistry A", "volume": "123", "number": "2", "publisher": "American Chemical Society", "pagerange": "590-600", "id_number": "CaltechAUTHORS:20181217-080428895", "issn": "1089-5639", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20181217-080428895", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Camille and Henry Dreyfus Foundation" }, { "agency": "NSF", "grant_number": "CHE-1508526" }, { "agency": "University of Copenhagen" }, { "agency": "Danish Center for Scientific Computing" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1021/acs.jpca.8b09745", "primary_object": { "basename": "jp8b09745_si_001.pdf", "url": "https://authors.library.caltech.edu/records/g74pq-te194/files/jp8b09745_si_001.pdf" }, "resource_type": "article", "pub_year": "2019", "author_list": "Praske, Eric; Otkj\u00e6r, Rasmus V.; et el." }, { "id": "https://authors.library.caltech.edu/records/v62r9-4mh73", "eprint_id": 92182, "eprint_status": "archive", "datestamp": "2023-08-19 13:26:22", "lastmod": "2023-10-20 00:03:06", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Vasquez-K-T", "name": { "family": "Vasquez", "given": "Krystal T." }, "orcid": "0000-0003-4540-4212" }, { "id": "Allen-Hannah-M", "name": { "family": "Allen", "given": "Hannah M." }, "orcid": "0000-0002-4218-5133" }, { "id": "Crounse-J-D", "name": { "family": "Crounse", "given": "John D." }, "orcid": "0000-0001-5443-729X" }, { "id": "Praske-E", "name": { "family": "Praske", "given": "Eric" }, "orcid": "0000-0001-7169-4423" }, { "id": "Xu-Lu", "name": { "family": "Xu", "given": "Lu" }, "orcid": "0000-0002-0021-9876" }, { "id": "Noelscher-A-C", "name": { "family": "Noelscher", "given": "Anke C." }, "orcid": "0000-0002-7864-4020" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "Low-pressure gas chromatography with chemical ionization mass spectrometry for quantification of multifunctional organic compounds in the atmosphere", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2018 Author(s). This work is distributed under the Creative Commons Attribution 4.0 License. \n\nReceived: 6 July 2018 \u2013 Discussion started: 18 July 2018. Revised: 2 November 2018 \u2013 Accepted: 8 December 2018 \u2013 Published: 21 December 2018. \n\nWe would like to thank Steve Bertman, Phil Stevens, and the University of Michigan Biological Station (UMBS) for organizing the PROPHET 2016 campaign. We are indebted to the many PROPHET participants who helped us move the instrument to and from the top of the tower safely. We also thank the Caltech campus and affiliated staff for accommodating the summer 2017 study. The construction of the GC-HRToF-CIMS instrument was supported by the National Science Foundation (AGS-1428482), with additional NSF support (AGS-1240604) provided for the instrument field deployments. Work performed by Krystal T. Vasquez and Hannah M. Allen was supported by the National Science Foundation Graduate Research Fellowship (NSF GRFP). Krystal T. Vasquez also acknowledges support from an Earl C. Anthony Fellowship in chemistry during an early portion of this study. \n\nData availability: Data from the 2017 Caltech study are available at https://doi.org/10.22002/D1.971 (Vasquez et al., 2018). Additional data are available upon request to the corresponding authors. \n\nSupplement: The supplement related to this article is available online at: https://doi.org/10.5194/amt-11-6815-2018-supplement.\n\nAuthor contributions: POW, JDC, KTV, HMA, EP, and ACN designed and built the GC-HRToF-CIMS. KTV, HMA, and EP operated the instrument during PROPHET. KTV and LX operated the instrument during the Caltech field study. KTV analyzed data and KTV wrote the paper with contributions from all co-authors. \n\nThe authors declare that they have no conflict of interest.\n\nPublished - amt-11-6815-2018.pdf
Supplemental Material - amt-11-6815-2018-supplement.pdf
", "abstract": "Oxygenated volatile organic compounds (OVOCs) are formed during the oxidation of gas-phase hydrocarbons in the atmosphere. However, analytical challenges have hampered ambient measurements for many of these species, leaving unanswered questions regarding their atmospheric fate. We present the development of an in situ gas chromatography (GC) technique that, when combined with the sensitive and specific detection of chemical ionization mass spectrometry (CIMS), is capable of the isomer-resolved detection of a wide range of OVOCs. The instrument addresses many of the issues typically associated with chromatographic separation of such compounds (e.g., analyte degradation). The performance of the instrumentation is assessed through data obtained in the laboratory and during two field studies. We show that this instrument is able to successfully measure otherwise difficult-to-quantify compounds (e.g., organic hydroperoxides and organic nitrates) and observe the diurnal variations in a number of their isomers.", "date": "2018-12-21", "date_type": "published", "publication": "Atmospheric Measurement Techniques", "volume": "11", "number": "12", "publisher": "European Geosciences Union", "pagerange": "6815-6832", "id_number": "CaltechAUTHORS:20190109-154344511", "issn": "1867-8548", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190109-154344511", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "AGS-1428482" }, { "agency": "NSF", "grant_number": "AGS-1240604" }, { "agency": "NSF Graduate Research Fellowship" }, { "agency": "Earl C. Anthony Fellowhsip, Caltech" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/amt-11-6815-2018", "primary_object": { "basename": "amt-11-6815-2018-supplement.pdf", "url": "https://authors.library.caltech.edu/records/v62r9-4mh73/files/amt-11-6815-2018-supplement.pdf" }, "related_objects": [ { "basename": "amt-11-6815-2018.pdf", "url": "https://authors.library.caltech.edu/records/v62r9-4mh73/files/amt-11-6815-2018.pdf" } ], "resource_type": "article", "pub_year": "2018", "author_list": "Vasquez, Krystal T.; Allen, Hannah M.; et el." }, { "id": "https://authors.library.caltech.edu/records/d1ewa-bqg02", "eprint_id": 103509, "eprint_status": "archive", "datestamp": "2023-08-22 00:28:13", "lastmod": "2023-10-20 16:26:47", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "O'Dell-C-W", "name": { "family": "O'Dell", "given": "Christopher W." }, "orcid": "0000-0002-0271-8433" }, { "id": "Eldering-A", "name": { "family": "Eldering", "given": "Annmarie" }, "orcid": "0000-0003-1080-9922" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Crisp-D", "name": { "family": "Crisp", "given": "David" }, "orcid": "0000-0002-4573-9998" }, { "id": "Gunson-M-R", "name": { "family": "Gunson", "given": "Michael R." } }, { "id": "Fisher-B-M", "name": { "family": "Fisher", "given": "Brendan" } }, { "id": "Frankenberg-C", "name": { "family": "Frankenberg", "given": "Christian" }, "orcid": "0000-0002-0546-5857" }, { "id": "Kiel-M", "name": { "family": "Kiel", "given": "Matth\u00e4us" }, "orcid": "0000-0002-9784-962X" }, { "name": { "family": "Lindqvist", "given": "Hannakaisa" } }, { "id": "Mandrake-L", "name": { "family": "Mandrake", "given": "Lukas" } }, { "name": { "family": "Merrelli", "given": "Aronne" } }, { "id": "Natraj-V", "name": { "family": "Natraj", "given": "Vijay" }, "orcid": "0000-0003-3154-9429" }, { "name": { "family": "Nelson", "given": "Robert R." }, "orcid": "0000-0002-3471-5683" }, { "id": "Osterman-G-B", "name": { "family": "Osterman", "given": "Gregory B." } }, { "id": "Payne-V-H", "name": { "family": "Payne", "given": "Vivienne H." } }, { "name": { "family": "Taylor", "given": "Thomas E." }, "orcid": "0000-0002-1650-4882" }, { "name": { "family": "Wunch", "given": "Debra" }, "orcid": "0000-0002-4924-0377" }, { "id": "Drouin-B-J", "name": { "family": "Drouin", "given": "Brian J." } }, { "id": "Oyafuso-F-A", "name": { "family": "Oyafuso", "given": "Fabiano" }, "orcid": "0000-0002-8862-8737" }, { "id": "Chang-Albert-Y", "name": { "family": "Chang", "given": "Albert" } }, { "id": "McDuffie-J", "name": { "family": "McDuffie", "given": "James" }, "orcid": "0000-0002-9408-5695" }, { "id": "Smyth-M", "name": { "family": "Smyth", "given": "Michael" } }, { "name": { "family": "Baker", "given": "David F." } }, { "name": { "family": "Basu", "given": "Sourish" }, "orcid": "0000-0001-8605-5894" }, { "name": { "family": "Chevallier", "given": "Fr\u00e9d\u00e9ric" }, "orcid": "0000-0002-4327-3813" }, { "name": { "family": "Crowell", "given": "Sean M. R." }, "orcid": "0000-0001-8353-3707" }, { "name": { "family": "Feng", "given": "Liang" } }, { "name": { "family": "Palmer", "given": "Paul I." }, "orcid": "0000-0002-1487-0969" }, { "name": { "family": "Dubey", "given": "Mavendra" }, "orcid": "0000-0002-3492-790X" }, { "name": { "family": "Garc\u00eda", "given": "Omaira E." } }, { "name": { "family": "Griffith", "given": "David W. T." }, "orcid": "0000-0002-7986-1924" }, { "name": { "family": "Hase", "given": "Frank" } }, { "name": { "family": "Iraci", "given": "Laura T." }, "orcid": "0000-0002-2859-5259" }, { "name": { "family": "Kivi", "given": "Rigel" }, "orcid": "0000-0001-8828-2759" }, { "name": { "family": "Morino", "given": "Isamu" }, "orcid": "0000-0003-2720-1569" }, { "name": { "family": "Notholt", "given": "Justus" } }, { "name": { "family": "Ohyama", "given": "Hirofumi" } }, { "name": { "family": "Petri", "given": "Christof" }, "orcid": "0000-0002-7010-5532" }, { "id": "Roehl-C-M", "name": { "family": "Roehl", "given": "Coleen M." }, "orcid": "0000-0001-5383-8462" }, { "name": { "family": "Sha", "given": "Mahesh K." } }, { "name": { "family": "Strong", "given": "Kimberly" }, "orcid": "0000-0001-9947-1053" }, { "name": { "family": "Sussmann", "given": "Ralf" } }, { "name": { "family": "Te", "given": "Yao" } }, { "name": { "family": "Uchino", "given": "Osamu" } }, { "name": { "family": "Velazco", "given": "Voltaire A." }, "orcid": "0000-0002-1376-438X" } ] }, "title": "Improved retrievals of carbon dioxide from Orbiting Carbon Observatory-2 with the version 8 ACOS algorithm", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 Author(s) 2018. This work is distributed under\nthe Creative Commons Attribution 4.0 License. Published by Copernicus Publications on behalf of the European Geosciences Union. \n\nReceived: 27 Jul 2018 \u2013 Discussion started: 16 Aug 2018 \u2013 Revised: 12 Nov 2018 \u2013 Accepted: 15 Nov 2018 \u2013 Published: 11 Dec 2018. \n\nPart of this work was conducted at the Jet Propulsion Laboratory, California Institute of Technology, under contract with the National Aeronautics and Space Administration (NASA) for the Orbiting Carbon Observatory 2 project. Work at Colorado State University and the Geology and Planetary Sciences Department at the California Institute of Technology was supported by subcontracts from the OCO-2 project. CarbonTracker CT2015 and CT-NRT.v2016-1 results provided by NOAA ESRL, Boulder, Colorado, USA, from the website at https://carbontracker.noaa.gov (last access: 4 December 2018). Jena CarboScope atmospheric inversion results provided by Christian R\u00f6denbeck and the Max Planck Institute for Biogeochemistry, from http://www.bgc-jena.mpg.de/CarboScope/ (last access: 4 December 2018). Special thanks to Geoff Toon for illuminating discussions regarding the TCCON CO2 prior. We also thank Julia Marshall and one anonymous referee for their reviews of the manuscript, which greatly improved its quality. \n\nAuthor contributions: CO and AE were involved in nearly all aspects of this work. PW provided critical guidance on nearly all aspects of the work, throughout all stages. DC provided guidance on instrument effects on the algorithm and feedback on the algorithm. MG provided project leadership and algorithm guidance. BF designed and implemented many tests and performed substantial data analysis. CF was involved in earlier phases of algorithm development, in particular with the IMAP-DOAS retrieval, SIF retrieval, and EOF development. MK contributed to the bias correction and analyzed TCCON target-mode data. HL provided the updated cloud ice optical properties. LM created the testing data sets and warn levels, and contributed to filtering and bias correction. AM contributed substantial analysis and wrote the BRDF section. VN guided implementation of the BRDF surface model. RN performed data analysis, in particular with regards to aerosol effects. GO led the target-mode operational effort and organized the validation activities. VP led the spectroscopy effort and wrote the spectroscopy section. TT edited early drafts of this paper and led the pre-filtering activities and analysis. DW provided critical analysis of TCCON/OCO-2 comparisons and advice regarding TCCON data use. BD and FO made important contributions to the ABSCO spectroscopy. AC operationalized the code and assisted in daily operations. JM and MS coded the L2 algorithm and processed testing data sets. DB, SB, FC, SC, LF, and PP provided model data used in the filtering, bias-correction, and validation efforts. MD, OG, DG, FH, LI, RK, IM, JN, HO, CP, CR, MKS, KS, RS, YT, OU, and VV provided TCCON data used in the filtering, bias-correction, and validation efforts. \n\nThe authors declare that they have no conflict of interest. \n\nEdited by: Helen Worden. Reviewed by: Julia Marshall and one anonymous referee.\n\nPublished - amt-11-6539-2018.pdf
", "abstract": "Since September 2014, NASA's Orbiting Carbon Observatory-2 (OCO-2) satellite has been taking measurements of reflected solar spectra and using them to infer atmospheric carbon dioxide levels. This work provides details of the OCO-2 retrieval algorithm, versions 7 and 8, used to derive the column-averaged dry air mole fraction of atmospheric CO\u2082 (X_(CO\u2082)) for the roughly 100\u2009000 cloud-free measurements recorded by OCO-2 each day. The algorithm is based on the Atmospheric Carbon Observations from Space (ACOS) algorithm which has been applied to observations from the Greenhouse Gases Observing SATellite (GOSAT) since 2009, with modifications necessary for OCO-2. Because high accuracy, better than 0.25\u2009%, is required in order to accurately infer carbon sources and sinks from X_(CO\u2082), significant errors and regional-scale biases in the measurements must be minimized. We discuss efforts to filter out poor-quality measurements, and correct the remaining good-quality measurements to minimize regional-scale biases. Updates to the radiance calibration and retrieval forward model in version 8 have improved many aspects of the retrieved data products. The version 8 data appear to have reduced regional-scale biases overall, and demonstrate a clear improvement over the version 7 data. In particular, error variance with respect to TCCON was reduced by 20\u2009% over land and 40\u2009% over ocean between versions 7 and 8, and nadir and glint observations over land are now more consistent. While this paper documents the significant improvements in the ACOS algorithm, it will continue to evolve and improve as the CO\u2082 data record continues to expand.", "date": "2018-12-11", "date_type": "published", "publication": "Atmospheric Measurement Techniques", "volume": "11", "number": "12", "publisher": "European Geosciences Union", "pagerange": "6539-6576", "id_number": "CaltechAUTHORS:20200528-073317396", "issn": "1867-8548", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200528-073317396", "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-11-6539-2018", "primary_object": { "basename": "amt-11-6539-2018.pdf", "url": "https://authors.library.caltech.edu/records/d1ewa-bqg02/files/amt-11-6539-2018.pdf" }, "resource_type": "article", "pub_year": "2018", "author_list": "O'Dell, Christopher W.; Eldering, Annmarie; et el." }, { "id": "https://authors.library.caltech.edu/records/bh5fz-23a55", "eprint_id": 90872, "eprint_status": "archive", "datestamp": "2023-08-24 00:06:33", "lastmod": "2023-10-19 14:58:38", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Romer-Paul-S", "name": { "family": "Romer", "given": "Paul S." }, "orcid": "0000-0002-4983-743X" }, { "id": "Wooldridge-Paul-J", "name": { "family": "Wooldridge", "given": "Paul J." }, "orcid": "0000-0003-2711-5900" }, { "id": "Crounse-John-D", "name": { "family": "Crounse", "given": "John D." }, "orcid": "0000-0001-5443-729X" }, { "id": "Kim-Michelle-J", "name": { "family": "Kim", "given": "Michelle J." }, "orcid": "0000-0002-4922-4334" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Dibb-Jack-E", "name": { "family": "Dibb", "given": "Jack E." }, "orcid": "0000-0003-3096-7709" }, { "id": "Scheuer-Eric", "name": { "family": "Scheuer", "given": "Eric" }, "orcid": "0000-0002-8283-5014" }, { "id": "Blake-Donald-R", "name": { "family": "Blake", "given": "Donald R." }, "orcid": "0000-0002-8283-5014" }, { "id": "Meinardi-Simone", "name": { "family": "Meinardi", "given": "Simone" }, "orcid": "0000-0003-4828-9889" }, { "id": "Brosius-Alexandra-L", "name": { "family": "Brosius", "given": "Alexandra L." }, "orcid": "0000-0003-2393-3834" }, { "id": "Thames-Alexander-B", "name": { "family": "Thames", "given": "Alexander B." } }, { "id": "Miller-David-O", "name": { "family": "Miller", "given": "David O." } }, { "id": "Brune-William-H", "name": { "family": "Brune", "given": "William H." }, "orcid": "0000-0002-1609-4051" }, { "id": "Hall-Samuel-R", "name": { "family": "Hall", "given": "Samuel R." }, "orcid": "0000-0002-2060-7112" }, { "id": "Ryerson-Thomas-B", "name": { "family": "Ryerson", "given": "Thomas B." }, "orcid": "0000-0003-2800-7581" }, { "id": "Cohen-Ronald-C", "name": { "family": "Cohen", "given": "Ronald C." }, "orcid": "0000-0001-6617-7691" } ] }, "title": "Constraints on aerosol nitrate photolysis as a potential source of HONO and NO_x", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2018 American Chemical Society. \n\nReceived: July 13, 2018; Revised: October 22, 2018; Accepted: November 8, 2018; Published: November 8, 2018. \n\nWe thank NASA for support via NNX15AT85G (Berkeley), NNX15AT97G and NNX14AP46G (Caltech), NNX14AP46G (UNH), and NNX16AD96G (to C.K.). M.J.K. was supported by NSF AGS Award No. 1524860. Methanol and acetaldehyde measurements were supported by the Austrian Federal Ministry for Transport, Innovation and Technology (bmvit) through the Austrian Research Promotion Agency (FFG). The authors thank Alan Fried for the formaldehyde measurements, Armin Wisthaler for the methanol and acetaldehyde measurements, Christoph Knote for the FLEXPART model results, Glenn Diskin for the CH4 and CO measurements, and Andrew Weinheimer and Denise Montzka for NO measurements. We thank Tamara Sparks and Alex Teng for assistance in the field, the ground and flight crew of the DC-8, and the KORUS-AQ science team. \n\nThe authors declare no competing financial interest.\n\nSupplemental Material - es8b03861_si_001.pdf
", "abstract": "The concentration of nitrogen oxides (NO_x) plays a central role in controlling air quality. On a global scale, the primary sink of NO_x is oxidation to form HNO_3. Gas-phase HNO_3 photolyses slowly with a lifetime in the troposphere of 10 days or more. However, several recent studies examining HONO chemistry have proposed that particle-phase HNO_3 undergoes photolysis 10\u2013300 times more rapidly than gas-phase HNO_3. We present here constraints on the rate of particle-phase HNO_3 photolysis based on observations of NO_x and HNO_3 collected over the Yellow Sea during the KORUS-AQ study in summer 2016. The fastest proposed photolysis rates are inconsistent with the observed NO_x to HNO_3 ratios. Negligible to moderate enhancements of the HNO_3 photolysis rate in particles, 1\u201330 times faster than in the gas phase, are most consistent with the observations. Small or moderate enhancement of particle-phase HNO_3 photolysis would not significantly affect the HNO_3 budget but could help explain observations of HONO and NO_x in highly aged air.", "date": "2018-12-04", "date_type": "published", "publication": "Environmental Science and Technology", "volume": "52", "number": "23", "publisher": "American Chemical Society", "pagerange": "13738-13746", "id_number": "CaltechAUTHORS:20181113-112610113", "issn": "0013-936X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20181113-112610113", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NNX15AT85G" }, { "agency": "NASA", "grant_number": "NNX15AT97G" }, { "agency": "NASA", "grant_number": "NNX14AP46G" }, { "agency": "NASA", "grant_number": "NNX16AD96G" }, { "agency": "NSF", "grant_number": "AGS-1524860" }, { "agency": "Bundesministerium f\u00fcr Verkehr, Innovation und Technologie (BMVIT)" }, { "agency": "\u00d6sterreichische Forschungsf\u00f6rderungsgesellschaft (FFG)" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1021/acs.est.8b03861", "primary_object": { "basename": "es8b03861_si_001.pdf", "url": "https://authors.library.caltech.edu/records/bh5fz-23a55/files/es8b03861_si_001.pdf" }, "resource_type": "article", "pub_year": "2018", "author_list": "Romer, Paul S.; Wooldridge, Paul J.; et el." }, { "id": "https://authors.library.caltech.edu/records/vca81-exf09", "eprint_id": 91955, "eprint_status": "archive", "datestamp": "2023-08-24 00:07:36", "lastmod": "2023-10-19 23:51:32", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Hedelius-J-K", "name": { "family": "Hedelius", "given": "Jacob K." }, "orcid": "0000-0003-2025-7519" }, { "id": "Liu-Junjie", "name": { "family": "Liu", "given": "Junjie" }, "orcid": "0000-0002-7184-6594" }, { "id": "Oda-Tomohiro", "name": { "family": "Oda", "given": "Tomohiro" } }, { "id": "Maksyutov-S", "name": { "family": "Maksyutov", "given": "Shamil" }, "orcid": "0000-0002-1200-9577" }, { "id": "Roehl-C-M", "name": { "family": "Roehl", "given": "Coleen M." }, "orcid": "0000-0001-5383-8462" }, { "id": "Iraci-L-T", "name": { "family": "Iraci", "given": "Laura T." }, "orcid": "0000-0002-2859-5259" }, { "id": "Podolske-J-R", "name": { "family": "Podolske", "given": "James R." } }, { "id": "Hillyard-P-W", "name": { "family": "Hillyard", "given": "Patrick W." } }, { "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": "Wunch-D", "name": { "family": "Wunch", "given": "Debra" }, "orcid": "0000-0002-4924-0377" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "Southern California megacity CO_2, CH_4, and CO flux estimates using ground- and space-based remote sensing and a Lagrangian model", "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: 23 May 2018 \u2013 Discussion started: 31 May 2018 \u2013 Revised: 12 Oct 2018 \u2013 Accepted: 30 Oct 2018 \u2013 Published: 16 Nov 2018. \n\nThe authors wish to acknowledge providers of data. OCO-2 lite files were produced by the OCO-2 project at the Jet Propulsion Laboratory, California Institute of Technology. Resources supporting OCO-2 retrievals were provided by the NASA High-End Computing (HEC) Program through the NASA Advanced Supercomputing (NAS) Division at Ames Research Center. Nightlight products were obtained from the Earth Observation Group, NOAA National Geophysical Data Center and are based on Suomi NPP satellite observations. The 0.1\u2218 methane inventory was produced by Harvard University in collaboration with the EPA. The authors gratefully acknowledge the NOAA Air Resources Laboratory (ARL) for the provision of the HYSPLIT transport model (http://www.ready.noaa.gov, last access: 12 November 2018) as well as the gridded archived meteorological data used in this publication. \n\nWe thank Ron Cohen, Nick Parazoo, Anna Karion, and Taylor Jones for helpful discussions. We thank Nasrin Pak for discussions on landfills. \n\nThis work was financially supported by NASA's OCO-2 project (grant no. NNN12AA01C) and NASA's carbon cycle and ecosystems research program (grant no. NNX14AI60G and NNX17AE15G). Tomohiro Oda is supported by the NASA Carbon Cycle Science program (grant no. NNX14AM76G). The Hestia data product was made possible through support from Purdue University Showalter Trust, the National Aeronautics and Space Administration grant 1491755, and the National Institute of Standards and Technology grants 70NANB14H321 and 70NANB16H264. The authors thank the referees for their comments. \n\nEdited by: Robert McLaren. Reviewed by:two anonymous referees. \n\nAuthor contributions. JKH, JuL, and POW were involved in the overall conceptualization, investigation, and methodology development. JKH carried out the formal analysis and visualization and wrote the original draft. POW secured funding and computational resources and provided supervision. TO and SM developed the ODIAC FF inventory and provided instructions on its use. KG and JiL developed the Hestia-LA FF inventory and provided instructions on its use. CMR, LTI, JRP, PWH, DW, and POW provided TCCON data, which involved funding acquisition, site management, data processing, and QA/QC. JKH, JuL, TO, LTI, DW, and POW were involved in revising the paper. \n\nThe authors declare that they have no conflict of interest. \n\nData availability. TCCON data used in this study (GGG2014: Iraci, et al., 2014; Wennberg et al., 2014) are hosted at the TCCON data archive (https://tccondata.org/, last access: 23 November 2017) and are used in accordance with the Data Use Policy (https://tccon-wiki.caltech.edu/Network_Policy/Data_Use_Policy, last access: 23 November 2017). OCO-2 data (OCO-2 Science Team et al., 2017) are hosted by Goddard Earth Sciences (GES) Data and Information Services Center (DISC) (https://disc.gsfc.nasa.gov/datasets/OCO2_L2_Lite_FP_8r/summary, last access: 2 January 2018). ODIAC2016 data (Oda et al., 2015) are hosted by NIES (http://db.cger.nies.go.jp/dataset/ODIAC/, last access: 30 July 2018). Hestia-LA and Vulcan data can be obtained by contacting Kevin Gurney (Kevin.Gurney@nau.edu). Nightlight products were obtained from the Earth Observation Group, NOAA National Geophysical Data Center and are based on Suomi NPP satellite observations (http://ngdc.noaa.gov/eog/viirs/, last access: 16 August 2017). Gridded Harvard\u2013EPA emissions are hosted on the EPA website (https://www.epa.gov/ghgemissions/gridded-2012-methane-emissions, last access: 10 November 2016). NOAA gridded meteorological data are hosted on the NOAA ARL server (https://www.ready.noaa.gov/archives.php, last access 24 October 2017). The CARB regularly publishes emission inventories of various gases. CO inventories are available online (2017: https://www.arb.ca.gov/app/emsinv/2017/emssumcat.php, 2013: https://www.arb.ca.gov/app/emsinv/2013/emssumcat.php, 2009: https://www.arb.ca.gov/app/emsinv/fcemssumcat2009.php, last access: 12 November 2018), as are CH4 inventories (2017: https://www.arb.ca.gov/app/ghg/2000_2015/ghg_sector_data.php, 2013: https://www.arb.ca.gov/app/ghg/2000_2011/ghg_sector_data.php, 2009: https://www.arb.ca.gov/app/ghg/2000_2006/ghg_sector.php, last access: 12 November 2018).\n\nPublished - acp-18-16271-2018.pdf
", "abstract": "We estimate the overall CO_2, CH_4, and CO flux from the South Coast Air Basin using an inversion that couples Total Carbon Column Observing Network (TCCON) and Orbiting Carbon Observatory-2 (OCO-2) observations, with the Hybrid Single Particle Lagrangian Integrated Trajectory (HYSPLIT) model and the Open-source Data Inventory for Anthropogenic CO2 (ODIAC). Using TCCON data we estimate the direct net CO_2 flux from the SoCAB to be 104\u2009\u00b1\u200926\u2009Tg\u2009CO_2\u2009yr^(\u22121) for the study period of July 2013\u2013August 2016. We obtain a slightly higher estimate of 120\u2009\u00b1\u200930\u2009Tg\u2009CO)2\u2009yr^(\u22121) using OCO-2 data. These CO_2 emission estimates are on the low end of previous work. Our net CH_4 (360\u2009\u00b1\u200990\u2009Gg\u2009CH_4\u2009yr^(\u22121)) flux estimate is in agreement with central values from previous top-down studies going back to 2010 (342\u2013440\u2009Gg\u2009CH_4\u2009yr^(\u22121)). CO emissions are estimated at 487\u2009\u00b1\u2009122\u2009Gg\u2009CO\u2009yr^(\u22121), much lower than previous top-down estimates (1440\u2009Gg\u2009CO\u2009yr^(\u22121)). Given the decreasing emissions of CO, this finding is not unexpected. We perform sensitivity tests to estimate how much errors in the prior, errors in the covariance, different inversion schemes, or a coarser dynamical model influence the emission estimates. Overall, the uncertainty is estimated to be 25\u2009%, with the largest contribution from the dynamical model. Lessons learned here may help in future inversions of satellite data over urban areas.", "date": "2018-11-16", "date_type": "published", "publication": "Atmospheric Chemistry and Physics", "volume": "18", "number": "22", "publisher": "European Geosciences Union", "pagerange": "16271-16291", "id_number": "CaltechAUTHORS:20181221-105357109", "issn": "1680-7324", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20181221-105357109", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NNN12AA01C" }, { "agency": "NASA", "grant_number": "NNX14AI60G" }, { "agency": "NASA", "grant_number": "NNX17AE15G" }, { "agency": "NASA", "grant_number": "NNX14AM76G" }, { "agency": "Purdue University" }, { "agency": "NASA", "grant_number": "1491755" }, { "agency": "National Institute of Standards and Technology (NIST)", "grant_number": "70NANB14H321" }, { "agency": "National Institute of Standards and Technology (NIST)", "grant_number": "70NANB16H264" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/acp-18-16271-2018", "primary_object": { "basename": "acp-18-16271-2018.pdf", "url": "https://authors.library.caltech.edu/records/vca81-exf09/files/acp-18-16271-2018.pdf" }, "resource_type": "article", "pub_year": "2018", "author_list": "Hedelius, Jacob K.; Liu, Junjie; et el." }, { "id": "https://authors.library.caltech.edu/records/h3baw-xme47", "eprint_id": 103559, "eprint_status": "archive", "datestamp": "2023-08-24 00:08:46", "lastmod": "2023-10-20 16:29:38", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Borsdorff-T", "name": { "family": "Borsdorff", "given": "Tobias" }, "orcid": "0000-0002-4421-0187" }, { "id": "aan-de-Brugh-J", "name": { "family": "aan de Brugh", "given": "Joost" } }, { "id": "Hu-Haili", "name": { "family": "Hu", "given": "Haili" } }, { "id": "Hasekamp-O-P", "name": { "family": "Hasekamp", "given": "Otto" } }, { "id": "Sussmann-R", "name": { "family": "Sussmann", "given": "Ralf" } }, { "id": "Rettinger-M", "name": { "family": "Rettinger", "given": "Markus" } }, { "id": "Hase-Frank", "name": { "family": "Hase", "given": "Frank" } }, { "id": "Gross-Jochen", "name": { "family": "Gross", "given": "Jochen" } }, { "id": "Schneider-Matthias", "name": { "family": "Schneider", "given": "Matthias" } }, { "id": "Garcia-Omaira", "name": { "family": "Garcia", "given": "Omaira" } }, { "id": "Stremme-W", "name": { "family": "Stremme", "given": "Wolfgang" }, "orcid": "0000-0003-0791-3833" }, { "id": "Grutter-M", "name": { "family": "Grutter", "given": "Michel" }, "orcid": "0000-0001-9800-5878" }, { "id": "Feist-D-G", "name": { "family": "Feist", "given": "Dietrich G." }, "orcid": "0000-0002-5890-6687" }, { "id": "Arnold-S-G", "name": { "family": "Arnold", "given": "Sabrina G." } }, { "id": "De-Mazi\u00e8re-M", "name": { "family": "De Mazi\u00e8re", "given": "Martine" } }, { "id": "Kumar-Sha-Mahesh", "name": { "family": "Kumar Sha", "given": "Mahesh" } }, { "id": "Pollard-D-F", "name": { "family": "Pollard", "given": "David F." }, "orcid": "0000-0001-9923-2984" }, { "id": "Kiel-M", "name": { "family": "Kiel", "given": "Matth\u00e4us" }, "orcid": "0000-0002-9784-962X" }, { "id": "Roehl-C-M", "name": { "family": "Roehl", "given": "Coleen" }, "orcid": "0000-0001-5383-8462" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Toon-G-C", "name": { "family": "Toon", "given": "Geoffrey C." }, "orcid": "0000-0003-4174-7541" }, { "id": "Landgraf-J", "name": { "family": "Landgraf", "given": "Jochen" }, "orcid": "0000-0002-6069-0598" } ] }, "title": "Mapping carbon monoxide pollution from space down to city scales with daily global coverage", "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: 20 Apr 2018 \u2013 Discussion started: 15 May 2018 \u2013 Revised: 11 Sep 2018 \u2013 Accepted: 26 Sep 2018 \u2013 Published: 09 Oct 2018. \n\nWe would like to thank the team that created the TROPOMI instrument, consisting of the partnership between Airbus Defense and Space, KNMI, SRON and TNO, and commissioned by the Netherlands Space Office (NSO) and the European Space Agency (ESA). In particular, we acknowledge Ilse Aben and Ruud Hoogeveen, the SRON L1 team. Sentinel-5 Precursor is part of the EU Copernicus program. Sentinel-5 Precursor is an ESA mission on behalf of the European Commission (EC). The TROPOMI payload is a joint development by ESA and the NSO. The Sentinel-5 Precursor ground-segment development has been funded by ESA and with national contributions from the Netherlands, Germany, and Belgium. The TCCON site at R\u00e9union Island is operated by the Royal Belgian Institute for Space Aeronomy with financial support in 2014, 2015, 2016, 2017, and 2018 under the EU project ICOS-Inwire, the ministerial decree for ICOS (FR/35/IC2), and local activities supported by LACy/UMR8105 \u2013 Universit\u00e9 de La R\u00e9union. The Belgian co-authors are also supported by the PRODEX TROVA project. The measurements in Mexico City were made by the projects CONACYT (nos. 275239 and 239618) and UNAM-DGAPA-PAPIIT (nos. IN112216 and IN111418). Alfredo Rodrigez, Miguel Angle Robles, Delibes Flores Roman, Wilfrido Guti\u00e9rrez, and Alejandro Bezanilla are acknowledged for technical support. This research has been funded in part by the TROPOMI national program from the NSO. The TROPOMI data processing was carried out on the Dutch national e-infrastructure with the support of the SURF Cooperative. The operation of the Ascension Island TCCON site was funded by the Max Planck Society. \n\nData availability. The TROPOMI CO data set of this study is available for download at https://www.sron.nl/data (SRON, 2018). TCCON data are available from the TCCON Data Archive, hosted by CaltechDATA, California Institute of Technology, CA (US), https://tccondata.org/ (TCCONnetwork, 2018). The TROPOMI CO data are available via the Copernicus Open Access Hub https://s5phub.copernicus.eu. \n\nAuthor contributions. TB, JadB, HH, and OH did the TROPOMI CO retrieval and data analysis. RS, MR, FH, JG, MS, OG, WS, MG, DGF, SGA, MDM, MKS, DFP, MK, CR, POW, and GCT performed FTS measurements and retrievals for the various stations. JL supervised the study. All authors discussed the results and commented on the manuscript. \n\nThe authors declare that they have no conflict of interest. \n\nEdited by: Helen Worden. Reviewed by: two anonymous referees.\n\nPublished - amt-11-5507-2018.pdf
", "abstract": "On 13 October 2017, the European Space Agency (ESA) successfully launched the Sentinel-5 Precursor satellite with the Tropospheric Monitoring Instrument (TROPOMI) as its single payload. TROPOMI is the first of ESA's atmospheric composition Sentinel missions, which will provide complete long-term records of atmospheric trace gases for the coming 30 years as a contribution to the European Union's Earth Observing program Copernicus. One of TROPOMI's primary products is atmospheric carbon monoxide (CO). It is observed with daily global coverage and a high spatial resolution of 7\u00d77\u2009km\u00b2. The moderate atmospheric resistance time and the low background concentration leads to localized pollution hotspots of CO and allows the tracking of the atmospheric transport of pollution on regional to global scales. In this contribution, we demonstrate the groundbreaking performance of the TROPOMI CO product, sensing CO enhancements above cities and industrial areas and tracking, with daily coverage, the atmospheric transport of pollution from biomass burning regions. The CO data product is validated with two months of Fourier-transform spectroscopy (FTS) measurements at nine ground-based stations operated by the Total Carbon Column Observing Network (TCCON). We found a good agreement between both datasets with a mean bias of 6\u2009ppb (average of individual station biases) for both clear-sky and cloudy TROPOMI CO retrievals. Together with the corresponding standard deviation of the individual station biases of 3.8\u2009ppb for clear-sky and 4.0\u2009ppb for cloudy sky, it indicates that the CO data product is already well within the mission requirement.", "date": "2018-10-09", "date_type": "published", "publication": "Atmospheric Measurement Techniques", "volume": "11", "number": "10", "publisher": "European Geosciences Union", "pagerange": "5507-5518", "id_number": "CaltechAUTHORS:20200529-093433857", "issn": "1867-8548", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200529-093433857", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Netherlands Space Office" }, { "agency": "European Space Agency (ESA)" }, { "agency": "Royal Belgian Institute for Space Aeronomy" }, { "agency": "European Union", "grant_number": "FR/35/IC2" }, { "agency": "Universit\u00e9 de La R\u00e9union", "grant_number": "LACy/UMR8105" }, { "agency": "Consejo Nacional de Ciencia y Tecnolog\u00eda (CONACYT)", "grant_number": "275239" }, { "agency": "Consejo Nacional de Ciencia y Tecnolog\u00eda (CONACYT)", "grant_number": "239618" }, { "agency": "Programa de Apoyo a Proyectos de Investigaci\u00f3n e Innovaci\u00f3n Tecnol\u00f3gica (PAPIIT)", "grant_number": "IN112216" }, { "agency": "Programa de Apoyo a Proyectos de Investigaci\u00f3n e Innovaci\u00f3n Tecnol\u00f3gica (PAPIIT)", "grant_number": "IN111418" }, { "agency": "Max Planck Society" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/amt-11-5507-2018", "primary_object": { "basename": "amt-11-5507-2018.pdf", "url": "https://authors.library.caltech.edu/records/h3baw-xme47/files/amt-11-5507-2018.pdf" }, "resource_type": "article", "pub_year": "2018", "author_list": "Borsdorff, Tobias; aan de Brugh, Joost; et el." }, { "id": "https://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.edu/records/pn7zh-dpw83", "eprint_id": 87808, "eprint_status": "archive", "datestamp": "2023-08-19 10:58:30", "lastmod": "2023-10-18 21:27:25", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Allen-Hannah-M", "name": { "family": "Allen", "given": "Hannah M." }, "orcid": "0000-0002-4218-5133" }, { "id": "Crounse-J-D", "name": { "family": "Crounse", "given": "John D." }, "orcid": "0000-0001-5443-729X" }, { "id": "Bates-K-H", "name": { "family": "Bates", "given": "Kelvin H." }, "orcid": "0000-0001-7544-9580" }, { "id": "Teng-Alexander-P", "name": { "family": "Teng", "given": "Alexander Paichung" }, "orcid": "0000-0002-6434-0501" }, { "id": "Krawiec-Thayer-M-P", "name": { "family": "Krawiec-Thayer", "given": "Mitchell P." } }, { "id": "Rivera-Rios-J-C", "name": { "family": "Rivera-Rios", "given": "Jean C." } }, { "id": "Keutsch-F-N", "name": { "family": "Keutsch", "given": "Frank N." } }, { "id": "St-Clair-J-M", "name": { "family": "St. Clair", "given": "Jason M." }, "orcid": "0000-0002-9367-5749" }, { "id": "Hanisco-T-F", "name": { "family": "Hanisco", "given": "Thomas F." }, "orcid": "0000-0001-9434-8507" }, { "id": "M\u00f8ller-K-H", "name": { "family": "M\u00f8ller", "given": "Kristian H." }, "orcid": "0000-0001-8070-8516" }, { "id": "Kjaergaard-H-G", "name": { "family": "Kjaergaard", "given": "Henrik G." }, "orcid": "0000-0002-7275-8297" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "Kinetics and Product Yields of the OH Initiated Oxidation of Hydroxymethyl Hydroperoxide", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2018 American Chemical Society. \n\nReceived: May 14, 2018; Revised: July 2, 2018; Published: July 11, 2018. \n\nThis material is based upon work supported by the National Science Foundation Graduate Research Fellowship under Grant No. DGE-1144469; in addition, we acknowledge support from the NSF (Grant Nos. 1240604, 1628530, and 1628491) and NASA (Grants NNX12AC06G and NNX14AP46G). We acknowledge the Center for Exploitation of Solar Energy, University of Copenhagen, and the Danish Center for Scientific Computing for funding. We thank Daniel Jacob and the Atmospheric Chemistry Modeling Group at Harvard University for their work on the GEOS-Chem model. In addition, SEAC4RS data from the Lidar Applications Group at the NASA Langley Research Center and from the Meteorological Measurement System (MMS) instrument operated by Paul Bui's group from the NASA Ames Research Center aided in the analysis presented here. \n\nThe authors declare no competing financial interest.\n\nSupplemental Material - jp8b04577_si_001.pdf
", "abstract": "Hydroxymethyl hydroperoxide (HMHP), formed in the reaction of the C1 Criegee intermediate with water, is among the most abundant organic peroxides in the atmosphere. Although reaction with OH is thought to represent one of the most important atmospheric removal processes for HMHP, this reaction has been largely unstudied in the laboratory. Here, we present measurements of the kinetics and products formed in the reaction of HMHP with OH. HMHP was oxidized by OH in an environmental chamber; the decay of the hydroperoxide and the formation of formic acid and formaldehyde were monitored over time using CF_3O\u2013 chemical ionization mass spectrometry (CIMS) and laser-induced fluorescence (LIF). The loss of HMHP by reaction with OH is measured relative to the loss of 1,2-butanediol [k_(1,2-butanediol+OH) = (27.0 \u00b1 5.6) \u00d7 10^(\u201312) cm^3 molecule^(\u20131)s^(\u20131)]. We find that HMHP reacts with OH at 295 K with a rate coefficient of (7.1 \u00b1 1.5) \u00d7 10^(\u201312) cm^3molecule^(\u20131)s^(\u20131), with the formic acid to formaldehyde yield in a ratio of 0.88 \u00b1 0.21 and independent of NO concentration (3 \u00d7 10^(10) \u2013 1.5 \u00d7 10^(13) molecules cm^(\u20133)). We suggest that, exclusively, abstraction of the methyl hydrogen of HMHP results in formic acid, while abstraction of the hydroperoxy hydrogen results in formaldehyde. We further evaluate the relative importance of HMHP sinks and use global simulations from GEOS-Chem to estimate that HMHP oxidation by OH contributes 1.7 Tg yr^(\u20131) (1\u20133%) of global annual formic acid production.", "date": "2018-08-02", "date_type": "published", "publication": "Journal of Physical Chemistry A", "volume": "122", "number": "30", "publisher": "American Chemical Society", "pagerange": "6292-6302", "id_number": "CaltechAUTHORS:20180712-133224483", "issn": "1089-5639", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180712-133224483", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF Graduate Research Fellowship", "grant_number": "DGE-1144469" }, { "agency": "NSF", "grant_number": "AGS-1240604" }, { "agency": "NSF", "grant_number": "AGS-1628530" }, { "agency": "NSF", "grant_number": "AGS-1628491" }, { "agency": "NASA", "grant_number": "NNX12AC06G" }, { "agency": "NASA", "grant_number": "NNX14AP46G" }, { "agency": "University of Copenhagen" }, { "agency": "Danish Center for Scientific Computing" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1021/acs.jpca.8b04577", "primary_object": { "basename": "jp8b04577_si_001.pdf", "url": "https://authors.library.caltech.edu/records/pn7zh-dpw83/files/jp8b04577_si_001.pdf" }, "resource_type": "article", "pub_year": "2018", "author_list": "Allen, Hannah M.; Crounse, John D.; et el." }, { "id": "https://authors.library.caltech.edu/records/zpa8p-42b47", "eprint_id": 87257, "eprint_status": "archive", "datestamp": "2023-08-22 01:55:51", "lastmod": "2023-10-18 20:59:25", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Silvern-R-F", "name": { "family": "Silvern", "given": "R. F." }, "orcid": "0000-0002-6683-3238" }, { "id": "Jacob-D-J", "name": { "family": "Jacob", "given": "D. J." }, "orcid": "0000-0002-6373-3100" }, { "id": "Travis-K-R", "name": { "family": "Travis", "given": "K. R." }, "orcid": "0000-0003-1628-0353" }, { "id": "Sherwen-T", "name": { "family": "Sherwen", "given": "T." }, "orcid": "0000-0002-3006-3876" }, { "id": "Evans-M-J", "name": { "family": "Evans", "given": "M. J." }, "orcid": "0000-0003-4775-032X" }, { "id": "Cohen-R-C", "name": { "family": "Cohen", "given": "R. C." }, "orcid": "0000-0001-6617-7691" }, { "id": "Laughner-J-L", "name": { "family": "Laughner", "given": "J. L." }, "orcid": "0000-0002-8599-4555" }, { "id": "Hall-S-R", "name": { "family": "Hall", "given": "S. R." }, "orcid": "0000-0002-2060-7112" }, { "id": "Ullmann-K", "name": { "family": "Ullmann", "given": "K." }, "orcid": "0000-0002-4724-9634" }, { "id": "Crounse-J-D", "name": { "family": "Crounse", "given": "J. D." }, "orcid": "0000-0001-5443-729X" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Peischl-J", "name": { "family": "Peischl", "given": "J." }, "orcid": "0000-0002-9320-7101" }, { "id": "Pollack-I-B", "name": { "family": "Pollack", "given": "I. B." }, "orcid": "0000-0001-7151-9756" } ] }, "title": "Observed NO/NO_2 Ratios in the Upper Troposphere Imply Errors in NO-NO_2-O_3 Cycling Kinetics or an Unaccounted NO_x Reservoir", "ispublished": "pub", "full_text_status": "public", "keywords": "NOx; upper troposphere; SEAC4RS; GEOS-Chem; kinetics", "note": "\u00a9 2018 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 OCT 2017; Accepted 20 APR 2018; Accepted article online 30 APR 2018; Published online 12 MAY 2018. \n\nWe thank Tom Ryerson for his measurements of NO and O_3 from the NOAA NO_yO_3 instrument. This work was supported by the NASA Earth Science Division and USEPA grant 83587201. Its contents are solely the responsibility of the grantee and do not necessarily represent the official views of the USEPA. Further, USEPA does not endorse the purchase of any commercial products or services mentioned in the publication. SEAC^4RS airborne measurements are available from the NASA LaRC Airborne Science Data for Atmospheric Composition (http://www\u2010air.larc.nasa.gov/cgi\u2010bin/ArcView/seac4rs). OMI NO_2 observations are available from the NASA Goddard Earth Sciences Data and Information Services Center (https://aura.gesdisc.eosdis.nasa.gov/data/Aura_OMI_Level2/OMNO2.003/).\n\nPublished - Silvern_et_al-2018-Geophysical_Research_Letters.pdf
", "abstract": "Observations from the SEAC^4RS aircraft campaign over the southeast United States in August\u2013September 2013 show NO/NO_2 concentration ratios in the upper troposphere that are approximately half of photochemical equilibrium values computed from Jet Propulsion Laboratory (JPL) kinetic data. One possible explanation is the presence of labile NO_x reservoir species, presumably organic, decomposing thermally to NO_2 in the instrument. The NO_2 instrument corrects for this artifact from known labile HNO_4 and CH_3O_2NO_2 NO_x reservoirs. To bridge the gap between measured and simulated NO_2, additional unaccounted labile NO_x reservoir species would have to be present at a mean concentration of ~40 ppt for the SEAC^4RS conditions (compared with 197 ppt for NOx). An alternative explanation is error in the low\u2010temperature rate constant for the NO + O_3 reaction (30% 1\u2010\u03c3 uncertainty in JPL at 240 K) and/or in the spectroscopic data for NO_2 photolysis (20% 1\u2010\u03c3 uncertainty). Resolving this discrepancy is important for understanding global budgets of tropospheric oxidants and for interpreting satellite observations of tropospheric NO_2 columns.", "date": "2018-05-16", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "45", "number": "9", "publisher": "American Geophysical Union", "pagerange": "4466-4474", "id_number": "CaltechAUTHORS:20180620-102535509", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180620-102535509", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA" }, { "agency": "Environmental Protection Agency (EPA)", "grant_number": "83587201" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2018GL077728", "primary_object": { "basename": "Silvern_et_al-2018-Geophysical_Research_Letters.pdf", "url": "https://authors.library.caltech.edu/records/zpa8p-42b47/files/Silvern_et_al-2018-Geophysical_Research_Letters.pdf" }, "resource_type": "article", "pub_year": "2018", "author_list": "Silvern, R. F.; Jacob, D. J.; et el." }, { "id": "https://authors.library.caltech.edu/records/0ycj1-j8k76", "eprint_id": 86090, "eprint_status": "archive", "datestamp": "2023-08-22 01:54:17", "lastmod": "2023-10-18 19:15:12", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Oh-Young-Suk", "name": { "family": "Oh", "given": "Young-Suk" } }, { "id": "Kenea-S-T", "name": { "family": "Kenea", "given": "S. Takele" } }, { "id": "Goo-Tae-Young", "name": { "family": "Goo", "given": "Tae-Young" } }, { "id": "Chung-Kyu-Sun", "name": { "family": "Chung", "given": "Kyu-Sun" } }, { "id": "Rhee-Jae-Sang", "name": { "family": "Rhee", "given": "Jae-Sang" } }, { "id": "Ou-Mi-Lim", "name": { "family": "Ou", "given": "Mi-Lim" } }, { "id": "Byun-Young-Hwa", "name": { "family": "Byun", "given": "Young-Hwa" } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Kiel-M", "name": { "family": "Kiel", "given": "Matth\u00e4us" }, "orcid": "0000-0002-9784-962X" }, { "id": "DiGangi-J-P", "name": { "family": "DiGangi", "given": "Joshua P." }, "orcid": "0000-0002-6764-8624" }, { "id": "Diskin-G-S", "name": { "family": "Diskin", "given": "Glenn S." }, "orcid": "0000-0002-3617-0269" }, { "id": "Velazco-V-A", "name": { "family": "Velazco", "given": "Voltaire A." }, "orcid": "0000-0002-1376-438X" }, { "id": "Griffith-D-W-T", "name": { "family": "Griffith", "given": "David W. T." }, "orcid": "0000-0002-7986-1924" } ] }, "title": "Characteristics of greenhouse gas concentrations derived from ground-based FTS spectra at Anmyeondo, South Korea", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 Author(s) 2018. 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: 30 Mar 2017 \u2013 Discussion started: 18 Apr 2017. Revised: 06 Feb 2018 \u2013 Accepted: 01 Mar 2018 \u2013 Published: 25 Apr 2018. \n\nThis research was supported by the Research and Development for KMA Weather, Climate, and Earth System Services (NIMS-2016-3100). David W. T. Griffith and Voltaire A. Velazco would like to acknowledge financial support from the Australian Research Council (ARC) for TCCON activities\n(DP160101598, DP140101552, DP110103118). We are grateful for the Jeong-Hoo Park from Park National Institute of Environmental Research and Ryan Bennett from NASA Langley Research Center and NASA's KORUS campaign team. Many thanks go to Haeyoung Lee for accessing in situ surface data of the Anmyeondo station and Kei Shiomi and the team for the provision of Saga FTS data. We thank the OCO-2 and GOSAT science teams for the delivery of data. Finally, we strongly appreciate the two anonymous reviewers who helped us to improve this manuscript. \n\nEdited by: Justus Notholt. \n\nReviewed by: Thomas Blumenstock and one anonymous referee.\n\nPublished - amt-11-2361-2018.pdf
", "abstract": "Since the late 1990s, the meteorological observatory established in Anmyeondo (36.5382\u00b0\u202fN, 126.3311\u00b0\u202fE, and 30\u202fm above mean sea level) has been monitoring several greenhouse gases such as CO_2, CH_4, N_2O, CFCs, and SF_6 as a part of the Global Atmosphere Watch (GAW) Program. A high resolution ground-based (g-b) Fourier transform spectrometer (FTS) was installed at this observation site in 2013 and has been operated within the frame work of the Total Carbon Column Observing Network (TCCON) since August 2014. The solar spectra recorded by the g-b FTS cover the spectral range 3800 to 16\u202f000\u202fcm^(\u22121) at a resolution of 0.02\u202fcm^(\u22121). In this work, the GGG2014 version of the TCCON standard retrieval algorithm was used to retrieve total column average CO_2 and CH_4 dry mole fractions (XCO_2, XCH_4) and from the FTS spectra. Spectral bands of CO_2 (at 6220.0 and 6339.5\u202fcm^(\u22121) center wavenumbers, CH_4 at 6002\u202fcm^(\u22121) wavenumber, and O_2 near 7880\u202fcm^(\u22121)) were used to derive the XCO_2 and XCH_4. In this paper, we provide comparisons of XCO_2 and XCH_4 between the aircraft observations and g-b FTS over Anmyeondo station. A comparison of 13 coincident observations of XCO_2 between g-b FTS and OCO-2 (Orbiting Carbon Observatory) satellite measurements are also presented for the measurement period between February 2014 and November 2017. OCO-2 observations are highly correlated with the g-b FTS measurements (r^2\u2009=\u20090.884) and exhibited a small positive bias (0.189\u202fppm). Both data set capture seasonal variations of the target species with maximum and minimum values in spring and late summer, respectively. In the future, it is planned to further utilize the FTS measurements for the evaluation of satellite observations such as Greenhouse Gases Observing Satellite (GOSAT, GOSAT-2). This is the first report of the g-b FTS observations of XCO_2 species over the Anmyeondo station.", "date": "2018-04-25", "date_type": "published", "publication": "Atmospheric Measurement Techniques", "volume": "11", "number": "4", "publisher": "European Geosciences Union", "pagerange": "2361-2374", "id_number": "CaltechAUTHORS:20180427-153025621", "issn": "1867-8548", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180427-153025621", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Research and Development for KMA Weather, Climate, and Earth System Services", "grant_number": "NIMS-2016-3100" }, { "agency": "Australian Research Council", "grant_number": "DP160101598" }, { "agency": "Australian Research Council", "grant_number": "DP140101552" }, { "agency": "Australian Research Council", "grant_number": "DP110103118" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/amt-11-2361-2018", "primary_object": { "basename": "amt-11-2361-2018.pdf", "url": "https://authors.library.caltech.edu/records/0ycj1-j8k76/files/amt-11-2361-2018.pdf" }, "resource_type": "article", "pub_year": "2018", "author_list": "Oh, Young-Suk; Kenea, S. Takele; et el." }, { "id": "https://authors.library.caltech.edu/records/86xwq-5jt04", "eprint_id": 85305, "eprint_status": "archive", "datestamp": "2023-08-22 01:53:47", "lastmod": "2023-10-18 18:04:59", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Bates-K-H", "name": { "family": "Bates", "given": "Kelvin H." }, "orcid": "0000-0001-7544-9580" }, { "id": "Crounse-J-D", "name": { "family": "Crounse", "given": "John D." }, "orcid": "0000-0001-5443-729X" }, { "id": "Dodson-L-G", "name": { "family": "Dodson", "given": "Leah G." }, "orcid": "0000-0001-5960-056X" }, { "id": "McVay-R-C", "name": { "family": "McVay", "given": "Renee C." }, "orcid": "0000-0001-7766-5009" }, { "id": "Mertens-L-A", "name": { "family": "Mertens", "given": "Laura A." } }, { "id": "Nguyen-Tran-B", "name": { "family": "Nguyen", "given": "Tran B." } }, { "id": "Praske-E", "name": { "family": "Praske", "given": "Eric" }, "orcid": "0000-0001-7169-4423" }, { "id": "Schwantes-R-H", "name": { "family": "Schwantes", "given": "Rebecca H." }, "orcid": "0000-0002-7095-3718" }, { "id": "Smarte-M-D", "name": { "family": "Smarte", "given": "Matthew D." } }, { "id": "St-Clair-J-M", "name": { "family": "St. Clair", "given": "Jason M." }, "orcid": "0000-0002-9367-5749" }, { "id": "Teng-Alexander-P", "name": { "family": "Teng", "given": "Alexander P." }, "orcid": "0000-0002-6434-0501" }, { "id": "Zhang-Xuan", "name": { "family": "Zhang", "given": "Xuan" }, "orcid": "0000-0003-1548-8021" }, { "id": "Seinfeld-J-H", "name": { "family": "Seinfeld", "given": "John H." }, "orcid": "0000-0003-1344-4068" } ] }, "title": "Gas-Phase Reactions of Isoprene and Its Major Oxidation Products", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2018 American Chemical Society. \n\nReceived: July 21, 2017; Publication Date (Web): March 9, 2018. \n\nAdditional Data: Additional detailed treatments of the reactions can be found at http://dx.doi.org/10.22002/D1.247, where the full and reduced mechanisms are made available as computer-readable codes for communal use and development. \n\nWe acknowledge support for this study by the Electric Power Research Institute, the National Science Foundation (AGS-1240604 and CHE-1508526), and the National Aeronautics and Space Administration (NNX14AP46G). P.O.W. thanks the University of Copenhagen and Henrik Kjaergaard for hosting his sabbatical during which much of this work was completed. He further thanks Henrik Kjaergaard, Kristian M\u00f8ller, and Rasmus Otkj\u00e6r for help with the H-shift chemistry. T.B.N. thanks the National Science Foundation AGS Postdoctoral Research Fellowship for support (AGS-1331360). L.G.D. was supported by an EPA STAR Fellowship and a Sandia Campus Executive Laboratory Directed Research and Development (LDRD) project. K.H.B. and M.D.S. acknowledge support from the National Science Foundation Graduate Research Fellowship program. The National Center for Atmospheric Research is sponsored by the National Science Foundation. Finally, we acknowledge the heroic effort of the anonymous reviewers; they provided excellent feedback that substantially improved our manuscript. \n\nThe authors declare no competing financial interest.\n\nSupplemental Material - cr7b00439_si_001.pdf
", "abstract": "Isoprene carries approximately half of the flux of non-methane volatile organic carbon emitted to the atmosphere by the biosphere. Accurate representation of its oxidation rate and products is essential for quantifying its influence on the abundance of the hydroxyl radical (OH), nitrogen oxide free radicals (NO_x), ozone (O_3), and, via the formation of highly oxygenated compounds, aerosol. We present a review of recent laboratory and theoretical studies of the oxidation pathways of isoprene initiated by addition of OH, O_3, the nitrate radical (NO_3), and the chlorine atom. From this review, a recommendation for a nearly complete gas-phase oxidation mechanism of isoprene and its major products is developed. The mechanism is compiled with the aims of providing an accurate representation of the flow of carbon while allowing quantification of the impact of isoprene emissions on HO_x and NO_x free radical concentrations and of the yields of products known to be involved in condensed-phase processes. Finally, a simplified (reduced) mechanism is developed for use in chemical transport models that retains the essential chemistry required to accurately simulate isoprene oxidation under conditions where it occurs in the atmosphere\u2014above forested regions remote from large NO_x emissions.", "date": "2018-04-11", "date_type": "published", "publication": "Chemical Reviews", "volume": "118", "number": "7", "publisher": "American Chemical Society", "pagerange": "3337-3390", "id_number": "CaltechAUTHORS:20180314-102355395", "issn": "0009-2665", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180314-102355395", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Electric Power Research Institute (EPRI)" }, { "agency": "NSF", "grant_number": "AGS-1240604" }, { "agency": "NSF", "grant_number": "CHE-1508526" }, { "agency": "NASA", "grant_number": "NNX14AP46G" }, { "agency": "NSF Graduate Research Fellowship", "grant_number": "AGS-1331360" }, { "agency": "Environmental Protection Agency (EPA)" }, { "agency": "Sandia National Laboratories" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1021/acs.chemrev.7b00439", "primary_object": { "basename": "cr7b00439_si_001.pdf", "url": "https://authors.library.caltech.edu/records/86xwq-5jt04/files/cr7b00439_si_001.pdf" }, "resource_type": "article", "pub_year": "2018", "author_list": "Wennberg, Paul O.; Bates, Kelvin H.; et el." }, { "id": "https://authors.library.caltech.edu/records/215vk-bhb98", "eprint_id": 86193, "eprint_status": "archive", "datestamp": "2023-08-22 01:50:58", "lastmod": "2023-10-18 19:20:56", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Carlton-A-G", "name": { "family": "Carlton", "given": "Annmarie G." } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "Synthesis of the Southeast Atmosphere Studies: Investigating Fundamental Atmospheric Chemistry Questions", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2018 American Meteorological Society. \n\nFinal Form: 17 August 2017; Published online: 19 April 2018. \n\nThis work was supported by NSF Grants 1242155 (Ann Marie Carlton), 1240611 (Dephine Farmer), 1250569 (Allen H. Goldstein), 1243354 (Jose L. Jimenez,), 1240604 (Paul O. Wennberg), 1216166 (Xianling Zhou), 1215712 (Jochen Stutz), 1217010 (Daniel A. Jaffe), and 1216707 (Noelle Selin); U.S. EPA Grants R83540401 (Jason Surratt), R83540701 (John Mak), R835410 (Anthanasios Nenes), R83541201 (Barbara J. Turpin), and R83587701 (Paul B. Shepson); and NOAA's Health of the Atmosphere and Atmospheric Chemistry, Carbon Cycle, and Climate Programs. Additional funding for the Southeast Atmosphere Studies was provided through NSF Grants 1246918 (William Brune, Penn State), 1242258 (Rodney Weber, George Tech), 1242932 (Don Collins, Texas A&M), 1242935 (Rob Griffin, Rice University), 1243356 (Doug Worsnop, Aerodyne Research Inc.), 1247421 (Frank Keutsch, Harvard), 1318307 (Jesse Kroll, MIT), 1241498 (Shanhu Lee, Kent State), and 1216743 (Christopher Cantrell, University of Colorado Boulder). This article was developed under an Assistance Agreement awarded by the U.S. Environmental Protection Agency. It has not been formally reviewed by the EPA. The views expressed in this document are solely those of the authors and do not necessarily reflect those of the agency. EPA does not endorse any products or commercial services mentioned in this publication.\n\nPublished - bams-d-16-0048.1.pdf
Supplemental Material - 10.1175_BAMS-D-16-0048.2.pdf
", "abstract": "The Southeast Atmosphere Studies (SAS), which included the Southern Oxidant and Aerosol Study (SOAS); the Southeast Nexus (SENEX) study; and the Nitrogen, Oxidants, Mercury and Aerosols: Distributions, Sources and Sinks (NOMADSS) study, was deployed in the field from 1 June to 15 July 2013 in the central and eastern United States, and it overlapped with and was complemented by the Studies of Emissions, Atmospheric Composition, Clouds and Climate Coupling by Regional Surveys (SEAC4RS) campaign. SAS investigated atmospheric chemistry and the associated air quality and climate-relevant particle properties. Coordinated measurements from six ground sites, four aircraft, tall towers, balloon-borne sondes, existing surface networks, and satellites provide in situ and remotely sensed data on trace-gas composition, aerosol physicochemical properties, and local and synoptic meteorology. Selected SAS findings indicate 1) dramatically reduced NOx concentrations have altered ozone production regimes; 2) indicators of \"biogenic\" secondary organic aerosol (SOA), once considered part of the natural background, were positively correlated with one or more indicators of anthropogenic pollution; and 3) liquid water dramatically impacted particle scattering while biogenic SOA did not. SAS findings suggest that atmosphere\u2013biosphere interactions modulate ambient pollutant concentrations through complex mechanisms and feedbacks not yet adequately captured in atmospheric models. The SAS dataset, now publicly available, is a powerful constraint to develop predictive capability that enhances model representation of the response and subsequent impacts of changes in atmospheric composition to changes in emissions, chemistry, and meteorology.", "date": "2018-03", "date_type": "published", "publication": "Bulletin of the American Meteorological Society", "volume": "99", "number": "3", "publisher": "American Meteorological Society", "pagerange": "547-567", "id_number": "CaltechAUTHORS:20180502-111923515", "issn": "0003-0007", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180502-111923515", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "AGS-1242155" }, { "agency": "NSF", "grant_number": "AGS-1240611" }, { "agency": "NSF", "grant_number": "AGS-1250569" }, { "agency": "NSF", "grant_number": "AGS-1243354" }, { "agency": "NSF", "grant_number": "AGS-1240604" }, { "agency": "NSF", "grant_number": "AGS-1216166" }, { "agency": "NSF", "grant_number": "AGS-1215712" }, { "agency": "NSF", "grant_number": "AGS-1217010" }, { "agency": "NSF", "grant_number": "AGS-1216707" }, { "agency": "Environmental Protection Agency (EPA)", "grant_number": "R83540401" }, { "agency": "Environmental Protection Agency (EPA)", "grant_number": "R83540701" }, { "agency": "Environmental Protection Agency (EPA)", "grant_number": "R835410" }, { "agency": "Environmental Protection Agency (EPA)", "grant_number": "R83541201" }, { "agency": "Environmental Protection Agency (EPA)", "grant_number": "R83587701" }, { "agency": "National Oceanic and Atmospheric Administration (NOAA)" }, { "agency": "NSF", "grant_number": "AGS-1246918" }, { "agency": "NSF", "grant_number": "AGS-1242258" }, { "agency": "NSF", "grant_number": "AGS-1242932" }, { "agency": "NSF", "grant_number": "AGS-1242935" }, { "agency": "NSF", "grant_number": "AGS-1243356" }, { "agency": "NSF", "grant_number": "AGS-1247421" }, { "agency": "NSF", "grant_number": "AGS-1318307" }, { "agency": "NSF", "grant_number": "AGS-1241498" }, { "agency": "NSF", "grant_number": "AGS-1216743" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1175/BAMS-D-16-0048.1", "primary_object": { "basename": "bams-d-16-0048.1.pdf", "url": "https://authors.library.caltech.edu/records/215vk-bhb98/files/bams-d-16-0048.1.pdf" }, "related_objects": [ { "basename": "10.1175_BAMS-D-16-0048.2.pdf", "url": "https://authors.library.caltech.edu/records/215vk-bhb98/files/10.1175_BAMS-D-16-0048.2.pdf" } ], "resource_type": "article", "pub_year": "2018", "author_list": "Carlton, Annmarie G. and Wennberg, Paul O." }, { "id": "https://authors.library.caltech.edu/records/rdtn2-nhj27", "eprint_id": 85183, "eprint_status": "archive", "datestamp": "2023-08-22 01:49:51", "lastmod": "2023-10-18 17:56:30", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Li-Jingyi", "name": { "family": "Li", "given": "Jingyi" } }, { "id": "Mao-Jingqiu", "name": { "family": "Mao", "given": "Jingqiu" } }, { "id": "Fiore-A-M", "name": { "family": "Fiore", "given": "Arlene M." } }, { "id": "Cohen-R-C", "name": { "family": "Cohen", "given": "Ronald C." }, "orcid": "0000-0001-6617-7691" }, { "id": "Crounse-J-D", "name": { "family": "Crounse", "given": "John D." }, "orcid": "0000-0001-5443-729X" }, { "id": "Teng-Alex-P", "name": { "family": "Teng", "given": "Alex P." } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Lee-Ben-H", "name": { "family": "Lee", "given": "Ben H." } }, { "id": "Lopez-Hilfiker-F-D", "name": { "family": "Lopez-Hilfiker", "given": "Felipe D." } }, { "id": "Thornton-J-A", "name": { "family": "Thornton", "given": "Joel A." }, "orcid": "0000-0002-5098-4867" }, { "id": "Peischl-J", "name": { "family": "Peischl", "given": "Jeff" }, "orcid": "0000-0002-9320-7101" }, { "id": "Pollack-I-B", "name": { "family": "Pollack", "given": "Ilana B." }, "orcid": "0000-0001-7151-9756" }, { "id": "Ryerson-T-B", "name": { "family": "Ryerson", "given": "Thomas B." }, "orcid": "0000-0003-2800-7581" }, { "id": "Veres-P-R", "name": { "family": "Veres", "given": "Patrick" } }, { "id": "Roberts-J-M", "name": { "family": "Roberts", "given": "James M." } }, { "id": "Neuman-J-A", "name": { "family": "Neuman", "given": "J. Andrew" } }, { "id": "Nowak-J-B", "name": { "family": "Nowak", "given": "John B." } }, { "id": "Wolfe-G-M", "name": { "family": "Wolfe", "given": "Glenn M." }, "orcid": "0000-0001-6586-4043" }, { "id": "Hanisco-T-F", "name": { "family": "Hanisco", "given": "Thomas F." }, "orcid": "0000-0001-9434-8507" }, { "id": "Fried-A", "name": { "family": "Fried", "given": "Alan" } }, { "id": "Singh-H-B", "name": { "family": "Singh", "given": "Hanwant B." } }, { "id": "Dibb-J-E", "name": { "family": "Dibb", "given": "Jack" }, "orcid": "0000-0003-3096-7709" }, { "id": "Paulot-F", "name": { "family": "Paulot", "given": "Fabien" }, "orcid": "0000-0001-7534-4922" }, { "id": "Horowitz-L-W", "name": { "family": "Horowitz", "given": "Larry W." } } ] }, "title": "Decadal changes in summertime reactive oxidized nitrogen and surface ozone over the Southeast United States", "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: 29 Jun 2017 \u2013 Discussion started: 13 Jul 2017. Revised: 23 Dec 2017 \u2013 Accepted: 03 Jan 2018 \u2013 Published: 16 Feb 2018. \n\nThe authors thank Vaishali Naik (NOAA GFDL) for providing emission inventories in the GFDL AM3 model and Leo Donner (NOAA GFDL) and William Cooke (UCAR/NOAA) for help with the convection scheme of AM3. Jingyi Li, Jingqiu Mao, and Larry W. Horowitz acknowledge support from the NOAA Climate Program Office under grant no. NA13OAR431007. Jingqiu Mao, Larry W. Horowitz, and Arlene M. Fiore acknowledge support from the NOAA Climate Program Office under grant no. NA14OAR4310133. John D. Crounse and Paul O. Wennberg acknowledge support from NASA grants (NNX12AC06G and NNX14AP46G). Jingyi Li acknowledges support from the Startup Foundation for Introducing Talent of NUIST grant no. 2243141701014 and the Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD). \n\nData availability. Observational datasets and modeling results are available upon request to the corresponding author (jmao2@alaska.edu). \n\nThe authors declare that they have no conflict of interest. \n\nEdited by: Nga Lee Ng \nReviewed by: three anonymous referees\n\nPublished - acp-18-2341-2018.pdf
Supplemental Material - acp-18-2341-2018-supplement.pdf
", "abstract": "Widespread efforts to abate ozone (O_3) smog have significantly reduced emissions of nitrogen oxides (NO_x) over the past 2 decades in the Southeast US, a place heavily influenced by both anthropogenic and biogenic emissions. How reactive nitrogen speciation responds to the reduction in NO_x emissions in this region remains to be elucidated. Here we exploit aircraft measurements from ICARTT (July\u2013August 2004), SENEX (June\u2013July 2013), and SEAC4RS (August\u2013September 2013) and long-term ground measurement networks alongside a global chemistry\u2013climate model to examine decadal changes in summertime reactive oxidized nitrogen (RON) and ozone over the Southeast US. We show that our model can reproduce the mean vertical profiles of major RON species and the total (NO_y) in both 2004 and 2013. Among the major RON species, nitric acid (HNO_3) is dominant (\u223c\u200942\u201345\u202f%), followed by NO_x (31\u202f%), total peroxy nitrates (\u03a3PNs; 14\u202f%), and total alkyl nitrates (\u03a3ANs; 9\u201312\u202f%) on a regional scale. We find that most RON species, including NO_x, \u03a3PNs, and HNO_3, decline proportionally with decreasing NO_x emissions in this region, leading to a similar decline in NO_y. This linear response might be in part due to the nearly constant summertime supply of biogenic VOC emissions in this region. Our model captures the observed relative change in RON and surface ozone from 2004 to 2013. Model sensitivity tests indicate that further reductions of NO_x emissions will lead to a continued decline in surface ozone and less frequent high-ozone events.", "date": "2018-02-16", "date_type": "published", "publication": "Atmospheric Chemistry and Physics", "volume": "18", "number": "3", "publisher": "European Geosciences Union", "pagerange": "2341-2361", "id_number": "CaltechAUTHORS:20180307-130604960", "issn": "1680-7324", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180307-130604960", "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": "NA13OAR431007" }, { "agency": "National Oceanic and Atmospheric Administration (NOAA)", "grant_number": "NA14OAR4310133" }, { "agency": "NASA", "grant_number": "NNX12AC06G" }, { "agency": "NASA", "grant_number": "NNX14AP46G" }, { "agency": "Nanjing University of Information Science and Technology", "grant_number": "2243141701014" }, { "agency": "Priority Academic Program Development of Jiangsu Higher Education Institutions" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/acp-18-2341-2018", "primary_object": { "basename": "acp-18-2341-2018-supplement.pdf", "url": "https://authors.library.caltech.edu/records/rdtn2-nhj27/files/acp-18-2341-2018-supplement.pdf" }, "related_objects": [ { "basename": "acp-18-2341-2018.pdf", "url": "https://authors.library.caltech.edu/records/rdtn2-nhj27/files/acp-18-2341-2018.pdf" } ], "resource_type": "article", "pub_year": "2018", "author_list": "Li, Jingyi; Mao, Jingqiu; et el." }, { "id": "https://authors.library.caltech.edu/records/381vy-8p435", "eprint_id": 84849, "eprint_status": "archive", "datestamp": "2023-08-22 01:48:41", "lastmod": "2023-10-18 16:45:28", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Sanchez-D", "name": { "family": "Sanchez", "given": "Dianne" } }, { "id": "Jeong-Daun", "name": { "family": "Jeong", "given": "Daun" } }, { "id": "Seco-R", "name": { "family": "Seco", "given": "Roger" } }, { "id": "Wrangham-I", "name": { "family": "Wrangham", "given": "Ian" } }, { "id": "Park-Jeong-Hoo", "name": { "family": "Park", "given": "Jeong-Hoo" } }, { "id": "Brune-W-H", "name": { "family": "Brune", "given": "William H." }, "orcid": "0000-0002-1609-4051" }, { "id": "Koss-A", "name": { "family": "Koss", "given": "Abigail" } }, { "id": "Gilman-J-B", "name": { "family": "Gilman", "given": "Jessica" } }, { "id": "de-Gouw-J-A", "name": { "family": "de Gouw", "given": "Joost" }, "orcid": "0000-0002-0385-1826" }, { "id": "Misztal-P-K", "name": { "family": "Misztal", "given": "Pawel" }, "orcid": "0000-0003-1060-1750" }, { "id": "Goldstein-A-H", "name": { "family": "Goldstein", "given": "Allen" }, "orcid": "0000-0003-4014-4896" }, { "id": "Baumann-K", "name": { "family": "Baumann", "given": "Karsten" } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Keutsch-F-N", "name": { "family": "Keutsch", "given": "Frank N." } }, { "id": "Guenther-A-B", "name": { "family": "Guenther", "given": "Alex" }, "orcid": "0000-0001-6283-8288" }, { "id": "Kim-Saewung", "name": { "family": "Kim", "given": "Saewung" } } ] }, "title": "Intercomparison of OH and OH reactivity measurements in a high isoprene and low NO environment during the Southern Oxidant and Aerosol Study (SOAS)", "ispublished": "pub", "full_text_status": "public", "keywords": "Hydroxyl radical; OH reactivity; Intercomparison; Isoprene; SOAS", "note": "\u00a9 2017 Elsevier Ltd. \n\nReceived 23 May 2017, Revised 16 October 2017, Accepted 24 October 2017, Available online 31 October 2017. \n\nThis research was supported by US EPA STAR Grant #835400.\n\nSupplemental Material - 1-s2.0-S1352231017307306-mmc1.docx
", "abstract": "We intercompare OH and OH reactivity datasets from two different techniques, chemical ionization mass spectrometry (CIMS) and laser-induced fluorescence (LIF) in a high isoprene and low NO environment in a southeastern US forest during the Southern Oxidant and Aerosol Study (SOAS). An LIF instrument measured OH and OH reactivity at the top of a tower, a CIMS instrument measured OH at the top of the tower, and a CIMS based comparative reactivity method (CRM-CIMS) instrument deployed at the base of the tower measured OH reactivity. Averaged diel variations of OH and OH reactivity from these datasets agree within analytical uncertainty and correlations of LIF versus CIMS for OH and OH reactivity have slopes of 0.65 and 0.97, respectively. However, there are systematic differences between the measurement datasets. The CRM-CIMS measurements of OH reactivity were \u223c16% lower than those by the LIF technique in the late afternoon. We speculate that it is caused by losses in the sampling line down to the CRM-CIMS instrument. On the other hand, we could not come up with a reasonable explanation for the difference in the LIF and CIMS OH datasets for early morning and late afternoon when OH is below 1 \u00d7 106 molecules cm\u22123. Nonetheless, results of this intercomparison exercise strengthen previous publications from the field site on OH concentrations and atmospheric reactivity.", "date": "2018-02", "date_type": "published", "publication": "Atmospheric Environment", "volume": "174", "publisher": "Elsevier", "pagerange": "227-236", "id_number": "CaltechAUTHORS:20180215-103004613", "issn": "1352-2310", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180215-103004613", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Environmental Protection Agency (EPA)", "grant_number": "835400" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/j.atmosenv.2017.10.056", "primary_object": { "basename": "1-s2.0-S1352231017307306-mmc1.docx", "url": "https://authors.library.caltech.edu/records/381vy-8p435/files/1-s2.0-S1352231017307306-mmc1.docx" }, "resource_type": "article", "pub_year": "2018", "author_list": "Sanchez, Dianne; Jeong, Daun; et el." }, { "id": "https://authors.library.caltech.edu/records/a2w0z-r2r54", "eprint_id": 83676, "eprint_status": "archive", "datestamp": "2023-08-22 01:47:51", "lastmod": "2023-10-17 23:24:15", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Hyttinen-N", "name": { "family": "Hyttinen", "given": "Noora" } }, { "id": "Otkj\u00e6r-R-V", "name": { "family": "Otkj\u00e6r", "given": "Rasmus V." }, "orcid": "0000-0002-6094-1828" }, { "id": "Iyer-S", "name": { "family": "Iyer", "given": "Siddharth" } }, { "id": "Kjaergaard-H-G", "name": { "family": "Kjaergaard", "given": "Henrik G." }, "orcid": "0000-0002-7275-8297" }, { "id": "Rissanen-M-P", "name": { "family": "Rissanen", "given": "Matti P." }, "orcid": "0000-0003-0463-8098" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Kurt\u00e9n-T", "name": { "family": "Kurt\u00e9n", "given": "Theo" }, "orcid": "0000-0002-6416-4931" } ] }, "title": "Computational Comparison of Different Reagent Ions in the Chemical Ionization of Oxidized Multifunctional Compounds", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2017 American Chemical Society.\n\nPublication Date (Web): December 4, 2017.\n\nWe thank John Crounse for helpful discussions. We thank the Academy of Finland (Grants 266388 and 299574) for funding, and CSC-IT Center for Science in Espoo, Finland, and\nUniversity of Copenhagen for computing time. POW thanks the University of Copenhagen for hosting his sabbatical and funding from NASA via grant NNX14AP46G-ACCDAM.\n\nAuthor Contributions: The manuscript was written through contributions of all authors. All authors have given approval to the final version of the manuscript. \n\nThe authors declare no competing financial interest.\n\nSupplemental Material - jp7b10015_si_001.pdf
", "abstract": "High pressure anion chemical ionization is commonly used for the detection of neutral molecules in the gas phase. The detection efficiency in these measurements depends on how strongly the reagent ion binds to the neutral target molecule. We have calculated the binding strength of nitrate (NO_3\u2013), acetate (CH_3C(O)O\u2013), lactate (CH_3CH(OH)C(O)O\u2013), trifluoroacetate (CF_3C(O)O\u2013), trifluoromethanolate (CF_3O\u2013), bromide (Br\u2013) and iodide (I\u2013) reagent ions to ten different products derived from the OH radical initiated oxidation of butadiene. We found that the binding of these oxidation products to the reagent ions depends almost linearly on the number of oxygen atoms in the target molecule, with the precise chemical identity of the compound (e.g. the number and relative position of hydroxyl or hydroperoxy groups) playing a more minor role. For acetate, the formation free energy decreases on average by around 4 kcal/mol when the number of oxygen atoms in the sample molecule increases by one. For the other reagent ions the corresponding decrease is around 3 kcal/mol. For all of the molecules studied, acetate forms the most stable clusters and I\u2013 the least stable. We also investigated the effect of humidity on the chemical ionization by calculating how strongly water molecules bind to both the reagent ions and the ion-molecule clusters. Water binds much more strongly to the reagent ion monomers compared to the reagent ion \"dimers\" (defined here as a cluster of the reagent anion with the corresponding neutral conjugate acid, e.g. HNO_3(NO_3\u2013)) or the ion-molecule clusters. This likely leads to a stronger humidity dependence when using reagent ions that are not able to form reagent ion dimers (such as CF_3C(O)O\u2013, CF_3O\u2013, Br\u2013 and I\u2013).", "date": "2018-01-11", "date_type": "published", "publication": "Journal of Physical Chemistry A", "volume": "122", "number": "1", "publisher": "American Chemical Society", "pagerange": "269-279", "id_number": "CaltechAUTHORS:20171204-155636314", "issn": "1089-5639", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20171204-155636314", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Academy of Finland", "grant_number": "266388" }, { "agency": "Academy of Finland", "grant_number": "299574" }, { "agency": "NASA", "grant_number": "NNX14AP46G-ACCDAM" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1021/acs.jpca.7b10015", "primary_object": { "basename": "jp7b10015_si_001.pdf", "url": "https://authors.library.caltech.edu/records/a2w0z-r2r54/files/jp7b10015_si_001.pdf" }, "resource_type": "article", "pub_year": "2018", "author_list": "Hyttinen, Noora; Otkj\u00e6r, Rasmus V.; et el." }, { "id": "https://authors.library.caltech.edu/records/5nd0b-rfp58", "eprint_id": 83952, "eprint_status": "archive", "datestamp": "2023-08-22 01:47:40", "lastmod": "2023-10-18 14:33:20", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Praske-Eric", "name": { "family": "Praske", "given": "Eric" }, "orcid": "0000-0001-7169-4423" }, { "id": "Otkj\u00e6r-Rasmus-V", "name": { "family": "Otkj\u00e6r", "given": "Rasmus V." }, "orcid": "0000-0002-6094-1828" }, { "id": "Crounse-John-D", "name": { "family": "Crounse", "given": "John D." }, "orcid": "0000-0001-5443-729X" }, { "id": "Hethcox-J-Caleb", "name": { "family": "Hethcox", "given": "J. Caleb" }, "orcid": "0000-0002-7712-308X" }, { "id": "Stoltz-B-M", "name": { "family": "Stoltz", "given": "Brian M." }, "orcid": "0000-0001-9837-1528" }, { "id": "Kjaergaard-Henrik-G", "name": { "family": "Kjaergaard", "given": "Henrik G." }, "orcid": "0000-0002-7275-8297" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "Atmospheric autoxidation is increasingly important in urban and suburban North America", "ispublished": "pub", "full_text_status": "public", "keywords": "atmospheric chemistry; air pollution; autoxidation", "note": "\u00a9 2017 National Academy of Sciences. Published under the PNAS license. \n\nEdited by Marsha I. Lester, University of Pennsylvania, Philadelphia, PA, and approved November 8, 2017 (received for review September 7, 2017). Published online before print December 18, 2017. \n\nWe thank Kristian H. M\u00f8ller for helpful discussions related to the implementation of MC-TST. J.C.H. thanks the Camille and Henry Dreyfus Postdoctoral Program in Environmental Chemistry for support. We acknowledge funding from National Science Foundation Grant CHE-1508526 as well as from the University of Copenhagen. \n\nAuthor contributions: J.D.C., H.G.K., and P.O.W. designed research; E.P., R.V.O., J.D.C., and H.G.K. performed research; J.C.H., B.M.S., and P.O.W. contributed new reagents/analytic tools; E.P., R.V.O., and J.D.C. analyzed data; and E.P., R.V.O., J.D.C., H.G.K., and P.O.W. 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/lookup/suppl/doi:10.1073/pnas.1715540115/-/DCSupplemental.\n\nPublished - PNAS-2018-Praske-64-9.pdf
Supplemental Material - pnas.1715540115.sapp.pdf
", "abstract": "Gas-phase autoxidation\u2014regenerative peroxy radical formation following intramolecular hydrogen shifts\u2014is known to be important in the combustion of organic materials. The relevance of this chemistry in the oxidation of organics in the atmosphere has received less attention due, in part, to the lack of kinetic data at relevant temperatures. Here, we combine computational and experimental approaches to investigate the rate of autoxidation for organic peroxy radicals (RO_2) produced in the oxidation of a prototypical atmospheric pollutant, n-hexane. We find that the reaction rate depends critically on the molecular configuration of the RO_2 radical undergoing hydrogen transfer (H-shift). RO_2 H-shift rate coefficients via transition states involving six- and seven-membered rings (1,5 and 1,6 H-shifts, respectively) of \u03b1-OH hydrogens (HOC-H) formed in this system are of order 0.1 s^(\u22121) at 296 K, while the 1,4 H-shift is calculated to be orders of magnitude slower. Consistent with H-shift reactions over a substantial energetic barrier, we find that the rate coefficients of these reactions increase rapidly with temperature and exhibit a large, primary, kinetic isotope effect. The observed H-shift rate coefficients are sufficiently fast that, as a result of ongoing NO_x emission reductions, autoxidation is now competing with bimolecular chemistry even in the most polluted North American cities, particularly during summer afternoons when NO levels are low and temperatures are elevated.", "date": "2018-01-02", "date_type": "published", "publication": "Proceedings of the National Academy of Sciences of the United States of America", "volume": "115", "number": "1", "publisher": "National Academy of Sciences", "pagerange": "64-69", "id_number": "CaltechAUTHORS:20171219-073339592", "issn": "0027-8424", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20171219-073339592", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Camille and Henry Dreyfus Foundation" }, { "agency": "NSF", "grant_number": "CHE-1508526" }, { "agency": "University of Copenhagen" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1073/pnas.1715540115", "pmcid": "PMC5776813", "primary_object": { "basename": "PNAS-2018-Praske-64-9.pdf", "url": "https://authors.library.caltech.edu/records/5nd0b-rfp58/files/PNAS-2018-Praske-64-9.pdf" }, "related_objects": [ { "basename": "pnas.1715540115.sapp.pdf", "url": "https://authors.library.caltech.edu/records/5nd0b-rfp58/files/pnas.1715540115.sapp.pdf" } ], "resource_type": "article", "pub_year": "2018", "author_list": "Praske, Eric; Otkj\u00e6r, Rasmus V.; et el." }, { "id": "https://authors.library.caltech.edu/records/zt14h-2km04", "eprint_id": 82526, "eprint_status": "archive", "datestamp": "2023-08-22 01:42:31", "lastmod": "2023-10-17 22:29:26", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Patra-P-K", "name": { "family": "Patra", "given": "Prabir K." }, "orcid": "0000-0001-5700-9389" }, { "id": "Crisp-D", "name": { "family": "Crisp", "given": "David" }, "orcid": "0000-0002-4573-9998" }, { "id": "Kaiser-J-W", "name": { "family": "Kaiser", "given": "Johannes W." }, "orcid": "0000-0003-3696-9123" }, { "id": "Wunch-D", "name": { "family": "Wunch", "given": "Debra" }, "orcid": "0000-0002-4924-0377" }, { "id": "Saeki-Tazu", "name": { "family": "Saeki", "given": "Tazu" } }, { "id": "Ichii-Kazuhito", "name": { "family": "Ichii", "given": "Kazuhito" }, "orcid": "0000-0002-8696-8084" }, { "id": "Sekiya-Takashi", "name": { "family": "Sekiya", "given": "Takashi" } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Feist-D-G", "name": { "family": "Feist", "given": "Dietrich G." }, "orcid": "0000-0002-5890-6687" }, { "id": "Pollard-D-F", "name": { "family": "Pollard", "given": "David F." }, "orcid": "0000-0001-9923-2984" }, { "id": "Griffith-D-W-T", "name": { "family": "Griffith", "given": "David W. T." }, "orcid": "0000-0002-7986-1924" }, { "id": "Velazco-V-A", "name": { "family": "Velazco", "given": "Voltaire A." }, "orcid": "0000-0002-1376-438X" }, { "id": "De-Mazi\u00e8re-M", "name": { "family": "De Mazi\u00e8re", "given": "M." } }, { "id": "Sha-M-K", "name": { "family": "Sha", "given": "Mahesh K." } }, { "id": "Roehl-C-M", "name": { "family": "Roehl", "given": "Coleen" }, "orcid": "0000-0001-5383-8462" }, { "id": "Chatterjee-A", "name": { "family": "Chatterjee", "given": "Abhishek" }, "orcid": "0000-0002-3680-0160" }, { "id": "Ishijima-Kentaro", "name": { "family": "Ishijima", "given": "Kentaro" } } ] }, "title": "The Orbiting Carbon Observatory (OCO-2) tracks 2\u20133 peta-gram increase in carbon release to the atmosphere during the 2014\u20132016 El Ni\u00f1o", "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: 03 October 2016; Accepted: 25 September 2017; Published online: 19 October 2017. \n\nThis work is supported by the Environment Research and Technology Development Fund (2\u20131401, 2\u20131701) of the Ministry of the Environment, Japan. PKP is grateful to Christopher O'Dell for sharing user-friendly OCO-2 and GOSAT data in NetCDF. This research has benefitted and inspired by discussions with Andrew Jacobson (also for NOAA CarbonTracker inversion fluxes), David Baker, Frederic Chevallier (also for CAMS inversion fluxes) and Sander Houweling. We thank Pieter Tans, Edward Dlugokencky and team members at NOAA ESRL for allowing us to use the in situ CO_2 measurements at the surface sites. The XCO_2 observation data were produced by the OCO-2 project at the Jet Propulsion Laboratory, California Institute of Technology, and obtained from the OCO-2 data archive maintained at the NASA Goddard Earth Science Data and Information Services Center. Part of the analysis described here was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration. The GFAS dataset was produced by EU's Copernicus Atmosphere Monitoring Service and distributed by the GEIA database ECCAD (http://eccad.sedoo.fr). The TCCON data were downloaded from the TCCON archive, hosted by CDIAC, at http://www.tccon.ornl.gov. The TCCON station on Ascension Island has been funded by the Max Planck Institute for Biogeochemistry. The TCCON site at Ile de la R\u00e9union is operated by the Royal Belgian Institute for Space Aeronomy with financial support in 2014 and 2015 under the EU project ICOS_Inwire and the ministerial decree for ICOS (FR/35/IC2) and local activities supported by LACy/UMR8105 - Universit\u00e9 de La R\u00e9union. TCCON data from Park Falls, Lamont, and Darwin are made possible with support from NASA. TCCON data were obtained from the TCCON Data Archive, hosted by the Carbon Dioxide Information Analysis Center (CDIAC) at Oak Ridge National Laboratory, Oak Ridge, Tennessee, U.S.A., http://tccon.ornl.gov. We thank both the three reviewers for critical but constructive comments, which have been very helpful for reshaping the contents of this article. \n\nAuthor Contributions: P.P., D.C. and J.K. conceived the experiments, P.P. conducted the model experiments and data analysis, D.C. provided guidance on the use of OCO-2 data, J.W. provided GFAS emissions, T.Sa. run ACTM inversions, T.Se. run tracer simulation, K.Ic. and A.C. supported data analysis, and D.W., P.W., D.F., D.P., D.G., V.V., M.D., M.S., C.R. provided TCCON measurements and supported analysis. K.Is. prepared JRA55 meteorology. All authors reviewed the manuscript and contributed to writing. \n\nThe authors declare that they have no competing interests.\n\nPublished - s41598-017-13459-0.pdf
Supplemental Material - 41598_2017_13459_MOESM1_ESM.pdf
", "abstract": "The powerful El Ni\u00f1o event of 2015\u20132016 \u2013 the third most intense since the 1950s \u2013 has exerted a large impact on the Earth's natural climate system. The column-averaged CO_2 dry-air mole fraction (XCO_2) observations from satellites and ground-based networks are analyzed together with in situ observations for the period of September 2014 to October 2016. From the differences between satellite (OCO-2) observations and simulations using an atmospheric chemistry-transport model, we estimate that, relative to the mean annual fluxes for 2014, the most recent El Ni\u00f1o has contributed to an excess CO_2 emission from the Earth's surface (land\u2009+\u2009ocean) to the atmosphere in the range of 2.4\u2009\u00b1\u20090.2 PgC (1 Pg\u2009=\u200910^(15)\u2009g) over the period of July 2015 to June 2016. The excess CO_2 flux is resulted primarily from reduction in vegetation uptake due to drought, and to a lesser degree from increased biomass burning. It is about the half of the CO_2 flux anomaly (range: 4.4\u20136.7 PgC) estimated for the 1997/1998 El Ni\u00f1o. The annual total sink is estimated to be 3.9\u2009\u00b1\u20090.2 PgC for the assumed fossil fuel emission of 10.1 PgC. The major uncertainty in attribution arise from error in anthropogenic emission trends, satellite data and atmospheric transport.", "date": "2017-10-18", "date_type": "published", "publication": "Scientific Reports", "volume": "7", "publisher": "Nature Publishing Group", "pagerange": "Art. No. 13567", "id_number": "CaltechAUTHORS:20171019-153802352", "issn": "2045-2322", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20171019-153802352", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Ministry of the Environment (Japan)" }, { "agency": "NASA/JPL/Caltech" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1038/s41598-017-13459-0", "pmcid": "PMC5648889", "primary_object": { "basename": "s41598-017-13459-0.pdf", "url": "https://authors.library.caltech.edu/records/zt14h-2km04/files/s41598-017-13459-0.pdf" }, "related_objects": [ { "basename": "41598_2017_13459_MOESM1_ESM.pdf", "url": "https://authors.library.caltech.edu/records/zt14h-2km04/files/41598_2017_13459_MOESM1_ESM.pdf" } ], "resource_type": "article", "pub_year": "2017", "author_list": "Patra, Prabir K.; Crisp, David; et el." }, { "id": "https://authors.library.caltech.edu/records/tfhts-4tq55", "eprint_id": 78740, "eprint_status": "archive", "datestamp": "2023-08-22 01:41:48", "lastmod": "2023-10-26 00:20:39", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Eldering-A", "name": { "family": "Eldering", "given": "A." }, "orcid": "0000-0003-1080-9922" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Crisp-D", "name": { "family": "Crisp", "given": "D." }, "orcid": "0000-0002-4573-9998" }, { "id": "Schimel-D-S", "name": { "family": "Schimel", "given": "D. S." }, "orcid": "0000-0003-3473-8065" }, { "id": "Gunson-M-R", "name": { "family": "Gunson", "given": "M. R." } }, { "id": "Chatterjee-Abhishek", "name": { "family": "Chatterjee", "given": "A." }, "orcid": "0000-0002-3680-0160" }, { "id": "Liu-J", "name": { "family": "Liu", "given": "J." } }, { "id": "Schwander-F-M", "name": { "family": "Schwander", "given": "F. M." } }, { "id": "Sun-Ying", "name": { "family": "Sun", "given": "Y." }, "orcid": "0000-0002-9819-1241" }, { "id": "O'Dell-C-W", "name": { "family": "O'Dell", "given": "C. W." } }, { "id": "Frankenberg-C", "name": { "family": "Frankenberg", "given": "C." }, "orcid": "0000-0002-0546-5857" }, { "id": "Taylor-T-E", "name": { "family": "Taylor", "given": "T." } }, { "id": "Fisher-B-M", "name": { "family": "Fisher", "given": "B." } }, { "id": "Osterman-G-B", "name": { "family": "Osterman", "given": "G. B." } }, { "id": "Wunch-D", "name": { "family": "Wunch", "given": "D." }, "orcid": "0000-0002-4924-0377" }, { "id": "Hakkarainen-J", "name": { "family": "Hakkarainen", "given": "J." } }, { "id": "Tamminen-T", "name": { "family": "Tamminen", "given": "J." } }, { "id": "Weir-B-A", "name": { "family": "Weir", "given": "B." } } ] }, "title": "The Orbiting Carbon Observatory-2 early science investigations of regional carbon dioxide fluxes", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2017 American Association for the Advancement of Science. \n\nReceived 11 December 2016; accepted 12 July 2017. \n\nRetrieved Level 2 OCO-2 XCO_2 (version v7Br) data used in this study are archived in a permanent repository at NASA's Goddard Space Flight Center's Earth Sciences Data and Information Services Center (GES-DISC) and are also available at NASA's Jet Propulsion Laboratory (http://co2.jpl.nasa.gov). Part of the 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. The movie was created by B. Weir, L. Ott, S. Pawson, H. Mitchell, and G. Shirah at Goddard Space Flight Center and the Scientific Visualization Studio. B.W., L.O., and S.P. were supported by the NASA Carbon Monitoring System and the OCO-2 Science Team NASA Research Opportunities in Space and Earth Sciences (ROSES) projects. K. Yuen assisted with figure production. J.H. and J.T. were supported by the Academy of Finland Inversion Algorithms and Quantification of Uncertainties in Atmospheric Remote Sensing (INQUIRE) (grant number 267442) and Carbon Balance under Changing Processes if Arctic and Subarctic Cryosphere (CARB-ARC) (grant number 285630) projects.\n\nAccepted Version - nihms915097.pdf
Supplemental Material - aam5745_Eldering_SM.pdf
Supplemental Material - aam5745s1.mp4
", "abstract": "NASA's Orbiting Carbon Observatory-2 (OCO-2) mission was motivated by the need to diagnose how the increasing concentration of atmospheric carbon dioxide (CO_2) is altering the productivity of the biosphere and the uptake of CO_2 by the oceans. Launched on 2 July 2014, OCO-2 provides retrievals of the column-averaged CO_2 dry-air mole fraction (XCO_2) as well as the fluorescence from chlorophyll in terrestrial plants. The seasonal pattern of uptake by the terrestrial biosphere is recorded in fluorescence and the drawdown of XCO_2 during summer. Launched just before one of the most intense El Ni\u00f1os of the past century, OCO-2 measurements of XCO_2 and fluorescence record the impact of the large change in ocean temperature and rainfall on uptake and release of CO_2 by the oceans and biosphere.", "date": "2017-10-13", "date_type": "published", "publication": "Science", "volume": "358", "number": "6360", "publisher": "American Association for the Advancement of Science", "pagerange": "Art. No. eaam5745", "id_number": "CaltechAUTHORS:20170630-172835482", "issn": "0036-8075", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170630-172835482", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA/JPL/Caltech" }, { "agency": "Academy of Finland", "grant_number": "267442" }, { "agency": "Academy of Finland", "grant_number": "285630" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1126/science.aam5745", "pmcid": "PMC5668686", "primary_object": { "basename": "aam5745s1.mp4", "url": "https://authors.library.caltech.edu/records/tfhts-4tq55/files/aam5745s1.mp4" }, "related_objects": [ { "basename": "nihms915097.pdf", "url": "https://authors.library.caltech.edu/records/tfhts-4tq55/files/nihms915097.pdf" }, { "basename": "aam5745_Eldering_SM.pdf", "url": "https://authors.library.caltech.edu/records/tfhts-4tq55/files/aam5745_Eldering_SM.pdf" } ], "resource_type": "article", "pub_year": "2017", "author_list": "Eldering, A.; Wennberg, P. O.; et el." }, { "id": "https://authors.library.caltech.edu/records/8fecy-vyr23", "eprint_id": 83104, "eprint_status": "archive", "datestamp": "2023-08-22 01:40:09", "lastmod": "2023-10-17 22:54:45", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Nault-B-A", "name": { "family": "Nault", "given": "B. A." }, "orcid": "0000-0001-9464-4787" }, { "id": "Laughner-J-L", "name": { "family": "Laughner", "given": "J. L." }, "orcid": "0000-0002-8599-4555" }, { "id": "Wooldridge-P-J", "name": { "family": "Wooldridge", "given": "P. J." } }, { "id": "Crounse-J-D", "name": { "family": "Crounse", "given": "J. D." }, "orcid": "0000-0001-5443-729X" }, { "id": "Dibb-J-E", "name": { "family": "Dibb", "given": "J." }, "orcid": "0000-0003-3096-7709" }, { "id": "Diskin-G-S", "name": { "family": "Diskin", "given": "G." }, "orcid": "0000-0002-3617-0269" }, { "id": "Peischl-J", "name": { "family": "Peischl", "given": "J." }, "orcid": "0000-0002-9320-7101" }, { "id": "Podolske-J-R", "name": { "family": "Podolske", "given": "J. R." } }, { "id": "Pollack-I-B", "name": { "family": "Pollack", "given": "I. B." }, "orcid": "0000-0001-7151-9756" }, { "id": "Ryerson-T-B", "name": { "family": "Ryerson", "given": "T. B." }, "orcid": "0000-0003-2800-7581" }, { "id": "Scheuer-E", "name": { "family": "Scheuer", "given": "E." } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Cohen-R-C", "name": { "family": "Cohen", "given": "R. C." }, "orcid": "0000-0001-6617-7691" } ] }, "title": "Lightning NO_x Emissions: Reconciling Measured and Modeled Estimates With Updated NO_x Chemistry", "ispublished": "pub", "full_text_status": "public", "keywords": "GEOS-Chem; DC3; OMI; NOx production per flash; lightning; upper tropospheric chemistry", "note": "\u00a9 2017 American Geophysical Union. \n\nReceived 2 JUN 2017; Accepted 29 AUG 2017; Accepted article online 5 SEP 2017; Published online 18 SEP 2017. \n\nData used are available at https://doi:10.5067/Aircraft/DC3/DC8/Aerosol-TraceGas (DC3), https://mirador.gsfc.nasa.gov/ (NASA SP), http://www.temis.nl/airpollution/no2.html (DOMINO), and https://doi.org/10.6078/D10P4P (GEOS-Chem). Relevant analysis code is hosted at https://doi.org/10.5281/zenodo.801885. B. A. N. was supported by the National Science Foundation Graduate Research Fellowship under grant DGE 1106400. J. L. L. was supported by the NASA ESS Fellowship NNX14AK89H. B. A. N., P. J. W., and R. C. C. acknowledge funding support from NASA (NNX12AB79G). J. D. C. and P. O. W. acknowledge funding support from NASA (NNX12AC06G and NNX14AP46G). J. D. and E. S. acknowledge funding from NASA (NNX12AB80G). This research used the Savio computational cluster resource provided by the Berkeley Research Computing program at the University of California, Berkeley (supported by the UC Berkeley Chancellor, Vice Chancellor of Research, and Office of the CIO). The authors also want to thank the ground and flight crews of the DC-8 and the DC3 science team.\n\nPublished - Nault_et_al-2017-Geophysical_Research_Letters.pdf
Supplemental Material - grl56410-sup-0001-2017GL074436-SI.pdf
", "abstract": "Lightning is one of the most important sources of upper tropospheric NO_x; however, there is a large spread in estimates of the global emission rates (2\u20138 Tg N yr^(\u22121)). We combine upper tropospheric in situ observations from the Deep Convective Clouds and Chemistry (DC3) experiment and global satellite-retrieved NO_2 tropospheric column densities to constrain mean lightning NO_x (LNO_x) emissions per flash. Insights from DC3 indicate that the NO_x lifetime is ~3 h in the region of outflow of thunderstorms, mainly due to production of methyl peroxy nitrate and alkyl and multifunctional nitrates. The lifetime then increases farther downwind from the region of outflow. Reinterpreting previous analyses using the 3 h lifetime reduces the spread among various methods that have been used to calculate mean LNO_x emissions per flash and indicates a global LNO_x emission rate of ~9 Tg N yr^(\u22121), a flux larger than the high end of recent estimates.", "date": "2017-09-28", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "44", "number": "18", "publisher": "American Geophysical Union", "pagerange": "9479-9488", "id_number": "CaltechAUTHORS:20171109-104417379", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20171109-104417379", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF Graduate Research Fellowship", "grant_number": "DGE-1106400" }, { "agency": "NASA Earth and Space Science Fellowship", "grant_number": "NNX14AK89H" }, { "agency": "NASA", "grant_number": "NNX12AB79G" }, { "agency": "NASA", "grant_number": "NNX12AC06G" }, { "agency": "NASA", "grant_number": "NNX14AP46G" }, { "agency": "NASA", "grant_number": "NNX12AB80G" }, { "agency": "University of California, Berkeley" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1002/2017GL074436", "primary_object": { "basename": "grl56410-sup-0001-2017GL074436-SI.pdf", "url": "https://authors.library.caltech.edu/records/8fecy-vyr23/files/grl56410-sup-0001-2017GL074436-SI.pdf" }, "related_objects": [ { "basename": "Nault_et_al-2017-Geophysical_Research_Letters.pdf", "url": "https://authors.library.caltech.edu/records/8fecy-vyr23/files/Nault_et_al-2017-Geophysical_Research_Letters.pdf" } ], "resource_type": "article", "pub_year": "2017", "author_list": "Nault, B. A.; Laughner, J. L.; et el." }, { "id": "https://authors.library.caltech.edu/records/crb45-hrx27", "eprint_id": 79597, "eprint_status": "archive", "datestamp": "2023-08-19 04:10:07", "lastmod": "2023-10-26 16:58:21", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Hedelius-J-K", "name": { "family": "Hedelius", "given": "Jacob K." }, "orcid": "0000-0003-2025-7519" }, { "id": "Feng-Sha", "name": { "family": "Feng", "given": "Sha" }, "orcid": "0000-0002-2376-0868" }, { "id": "Roehl-C-M", "name": { "family": "Roehl", "given": "Coleen M." }, "orcid": "0000-0001-5383-8462" }, { "id": "Wunch-D", "name": { "family": "Wunch", "given": "Debra" }, "orcid": "0000-0002-4924-0377" }, { "id": "Hillyard-P-W", "name": { "family": "Hillyard", "given": "Patrick W." } }, { "id": "Podolske-J-R", "name": { "family": "Podolske", "given": "James R." } }, { "id": "Iraci-L-T", "name": { "family": "Iraci", "given": "Laura T." }, "orcid": "0000-0002-2859-5259" }, { "id": "Patarasuk-R", "name": { "family": "Patarasuk", "given": "Risa" }, "orcid": "0000-0002-3961-4662" }, { "id": "Rao-Preeti", "name": { "family": "Rao", "given": "Preeti" }, "orcid": "0000-0002-5549-0583" }, { "id": "O'Keeffe-D", "name": { "family": "O'Keeffe", "given": "Darragh" } }, { "id": "Gurney-K-R", "name": { "family": "Gurney", "given": "Kevin R." }, "orcid": "0000-0001-9218-7164" }, { "id": "Lauvaux-T", "name": { "family": "Lauvaux", "given": "Thomas" } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "Emissions and topographic effects on column CO_2 (XCO_2) variations, with a focus on the Southern California Megacity", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2017 American Geophysical Union. \n\nIssue online: 25 Jul 2017; Version of Record online: 11 Jul 2017; Accepted manuscript online: 6 Jun 2017; Manuscript Accepted: 5 Jun 2017; Manuscript Revised: 30 May 2017; Manuscript Received: 4 Jan 2017. \n\nASTER GDEM is a product of METI and NASA. We gratefully acknowledge the NOAA Air Resources Laboratory (ARL) for the provision of the HYSPLIT transport and dispersion model (http://www.ready.noaa.gov) used in this publication. OCO-2 lite files were produced by the OCO-2 project at the Jet Propulsion Laboratory, California Institute of Technology, and obtained from the OCO-2 data archive maintained at the NASA Goddard Earth Science Data and Information Services Center. Nightlight products were obtained from the Earth Observation Group, NOAA National Geophysical Data Center and are based on Suomi NPP satellite observations (http://ngdc.noaa.gov/eog/viirs/). TCCON data are available from the CDIAC and will also be available through the Caltech library archive by 2018 [Iraci et al., 2014; Wennberg et al., 2014b, 2014a]. Model data are available upon request. We thank Chris O'Dell and the ACOS team for early access to the GOSAT-ACOS v7.3 data. We thank Camille Viatte, Eric Kort, and Kristal Verhulst for helpful discussions. The authors thank funding sources. This work is supported in part by the W. M. Keck Institute for Space Studies. The authors gratefully acknowledge TCCON funding from the NASA Carbon Cycle Science program (grant numbers NNX14AI60G and NNX17AE15G), and the Jet Propulsion Laboratory OCO-2 program (grant 1517180). Kevin R. Gurney thanks NIST grant 70NANB14H321. The authors also wish to thank the OCO-2 Science Team grant NNX15AI42G and NASA EVS ACT-America grant NNX15AG76G. The authors thank the referees for their comments. This paper is edited by A. Steiner and reviewed by two anonymous referees.\n\nPublished - Hedelius_et_al-2017-Journal_of_Geophysical_Research-_Atmospheres.pdf
Supplemental Material - jgrd53887-sup-0001-supinfo.pdf
", "abstract": "Within the California South Coast Air Basin (SoCAB), X_(CO)_2 varies significantly due to atmospheric dynamics and the nonuniform distribution of sources. X_(CO)_2 measurements within the basin have seasonal variation compared to the \"background\" due primarily to dynamics, or the origins of air masses coming into the basin. We observe basin-background differences that are in close agreement for three observing systems: Total Carbon Column Observing Network (TCCON) 2.3 \u00b1 1.2 ppm, Orbiting Carbon Observatory-2 (OCO-2) 2.4 \u00b1 1.5 ppm, and Greenhouse gases Observing Satellite 2.4 \u00b1 1.6 ppm (errors are 1\u03c3). We further observe persistent significant differences (\u223c0.9 ppm) in X_(CO)_2 between two TCCON sites located only 9 km apart within the SoCAB. We estimate that 20% (\u00b11\u03c3 confidence interval (CI): 0%, 58%) of the variance is explained by a difference in elevation using a full physics and emissions model and 36% (\u00b11\u03c3 CI: 10%, 101%) using a simple, fixed mixed layer model. This effect arises in the presence of a sharp gradient in any species (here we focus on CO_2) between the mixed layer (ML) and free troposphere. Column differences between nearby locations arise when the change in elevation is greater than the change in ML height. This affects the fraction of atmosphere that is in the ML above each site. We show that such topographic effects produce significant variation in X_(CO)_2 across the SoCAB as well.", "date": "2017-07-16", "date_type": "published", "publication": "Journal of Geophysical Research. Atmospheres", "volume": "122", "number": "13", "publisher": "American Geophysical Union", "pagerange": "7200-7215", "id_number": "CaltechAUTHORS:20170731-111148406", "issn": "2169-897X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170731-111148406", "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": "NNX14AI60G" }, { "agency": "NASA", "grant_number": "NNX17AE15G" }, { "agency": "JPL", "grant_number": "1517180" }, { "agency": "National Institute of Standards and Technology (NIST)", "grant_number": "70NANB14H321" }, { "agency": "NASA", "grant_number": "NNX15AI42G" }, { "agency": "NASA", "grant_number": "NNX15AG76G" } ] }, "local_group": { "items": [ { "id": "Keck-Institute-for-Space-Studies" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1002/2017JD026455", "primary_object": { "basename": "Hedelius_et_al-2017-Journal_of_Geophysical_Research-_Atmospheres.pdf", "url": "https://authors.library.caltech.edu/records/crb45-hrx27/files/Hedelius_et_al-2017-Journal_of_Geophysical_Research-_Atmospheres.pdf" }, "related_objects": [ { "basename": "jgrd53887-sup-0001-supinfo.pdf", "url": "https://authors.library.caltech.edu/records/crb45-hrx27/files/jgrd53887-sup-0001-supinfo.pdf" } ], "resource_type": "article", "pub_year": "2017", "author_list": "Hedelius, Jacob K.; Feng, Sha; et el." }, { "id": "https://authors.library.caltech.edu/records/2zj8w-gpj21", "eprint_id": 78472, "eprint_status": "archive", "datestamp": "2023-08-19 03:43:56", "lastmod": "2023-10-23 15:08:01", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Stavros-N", "name": { "family": "Stavros", "given": "Natasha" } }, { "id": "Schimel-D", "name": { "family": "Schimel", "given": "David" }, "orcid": "0000-0003-3473-8065" }, { "id": "Pavlick-R", "name": { "family": "Pavlick", "given": "Ryan" } }, { "id": "Serbin-S", "name": { "family": "Serbin", "given": "Shawn" } }, { "id": "Swann-A", "name": { "family": "Swann", "given": "Abigail" } }, { "id": "Duncanson-L", "name": { "family": "Duncanson", "given": "Laura" } }, { "id": "Fisher-J", "name": { "family": "Fisher", "given": "Joshua" } }, { "id": "Fassnacht-F", "name": { "family": "Fassnacht", "given": "Fabian" } }, { "id": "Ustin-S", "name": { "family": "Ustin", "given": "Susan" } }, { "id": "Dubayah-R", "name": { "family": "Dubayah", "given": "Ralph" } }, { "id": "Schweiger-A", "name": { "family": "Schweiger", "given": "Anna" } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "ISS observations offer insights into plant function", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 2017 Macmillan Publishers Limited, part of Springer Nature. \n\nPublished 22 June 2017. \n\nMany of these ideas were born and developed at the workshop on Exploring New Multi-Instrument Approaches to Observing Terrestrial Ecosystems and the Carbon Cycle from Space that occurred 5\u20139 October 2015 and was funded by the Keck Institute for Space Studies (KISS), organized by Michelle Judd, and hosted at the institute facility at California Institute of Technology in Pasadena, California. Additionally, the ideas in this article would not have been possible without the contributions of each participant. The majority of the work was internally funded and carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration. Also, S.S. was supported during the writing of this manuscript by the Next-Generation Ecosystem Experiments (NGEE) in the Tropics, which is supported by the Office of Biological and Environmental Research in the Department of Energy, Office of Science, and through the United States Department of Energy (grant no. DE-SC0012704) to Brookhaven National Laboratory. R.D. is funded by NASA Global Ecosystem Dynamics Investigation Mission (grant no. NNL15AA03C). P.W. acknowledges support from the NASA Carbon Cycle Science programme (grant no. NNX14AI60G). J.F. is funded by the NASA ECOSTRESS project. A.S. was funded by the National Science Foundation (NSF) and the National Aeronautics and Space Administration (NASA) through the Dimensions of Biodiversity programme (DEB-1342872). \n\nAuthor Contributions: E.N.S. is the lead writer for the manuscript, D.S. led discussions and helped articulate the key points of discussion for the manuscript, R.P. provided HISUI and OCO-3 information and panels in Fig. 2 as well as with edits for the manuscript, S.S. helped edit the general text, developed Fig. 2 and provided text for terrestrial biosphere models section, A.S. helped edit the general text and provided text for terrestrial biosphere models sections, L.D. provided the GEDI panel in Fig. 2 and text describing GEDI, J.B.F. helped with general editing and provided the ECOSTRESS panel in Fig. 2, F.F. helped with general editing, S.U. helped develop the original manuscript outline, R.D., A.S. and P.W. were key in contributing ideas for the manuscript. \n\nThe authors declare no competing financial interests.\n\nIn the version of this Comment previously published, in Box 1, the spacing of the GEDI footprints should have read 60 m along the track, not 25 m. Also the second affiliation for Susan Ustin was incorrect, she is only associated with the University of California, Davis. These errors have now been corrected.", "abstract": "In 2018 technologies on the International Space Station will provide ~1 year of synchronous observations of\necosystem composition, structure and function. We discuss these instruments and how they can be used\nto constrain global models and improve our understanding of the current state of terrestrial ecosystems.", "date": "2017-06-22", "date_type": "published", "publication": "Nature Ecology & Evolution", "volume": "1", "publisher": "Macmillan Publishers Limited", "pagerange": "Art. No. 0194", "id_number": "CaltechAUTHORS:20170622-142651594", "issn": "2397-334X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170622-142651594", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0012704" }, { "agency": "NASA", "grant_number": "NNL15AA03C" }, { "agency": "NASA", "grant_number": "NNX14AI60G" }, { "agency": "NSF", "grant_number": "DEB-1342872" }, { "agency": "Keck Institute for Space Studies (KISS)" } ] }, "local_group": { "items": [ { "id": "Keck-Institute-for-Space-Studies" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1038/s41559-017-0194", "resource_type": "article", "pub_year": "2017", "author_list": "Stavros, Natasha; Schimel, David; et el." }, { "id": "https://authors.library.caltech.edu/records/x56dw-pbr92", "eprint_id": 79846, "eprint_status": "archive", "datestamp": "2023-08-19 03:43:17", "lastmod": "2023-10-26 17:22:48", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Viatte-C", "name": { "family": "Viatte", "given": "Camille" } }, { "id": "Lauvaux-T", "name": { "family": "Lauvaux", "given": "Thomas" } }, { "id": "Hedelius-J-K", "name": { "family": "Hedelius", "given": "Jacob K." }, "orcid": "0000-0003-2025-7519" }, { "id": "Parker-H", "name": { "family": "Parker", "given": "Harrison" } }, { "id": "Chen-Jia", "name": { "family": "Chen", "given": "Jia" } }, { "id": "Jones-T", "name": { "family": "Jones", "given": "Taylor" }, "orcid": "0000-0001-5860-3419" }, { "id": "Franklin-J-E", "name": { "family": "Franklin", "given": "Jonathan E." } }, { "id": "Deng-Aijun-J", "name": { "family": "Deng", "given": "Aijun J." } }, { "id": "Gaudet-B", "name": { "family": "Gaudet", "given": "Brian" } }, { "id": "Verhulst-K-R", "name": { "family": "Verhulst", "given": "Kristal" }, "orcid": "0000-0001-5678-9678" }, { "id": "Duren-R-M", "name": { "family": "Duren", "given": "Riley" }, "orcid": "0000-0003-4723-5280" }, { "id": "Wunch-D", "name": { "family": "Wunch", "given": "Debra" }, "orcid": "0000-0002-4924-0377" }, { "id": "Roehl-C-M", "name": { "family": "Roehl", "given": "Coleen" }, "orcid": "0000-0001-5383-8462" }, { "id": "Dubey-M-K", "name": { "family": "Dubey", "given": "Manvendra K." } }, { "id": "Wofsy-S-C", "name": { "family": "Wofsy", "given": "Steven" }, "orcid": "0000-0002-3990-6737" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "Methane emissions from dairies in 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: 01 Apr 201; Discussion started: 27 Apr 2016. Revised: 11 Apr 2017; Accepted: 25 Apr 2017; Published: 21 Jun 2017.\n\nThe authors thank NASA and the W. M. Keck Institute for Space Studies for financial support. MKD acknowledges NASA CMS support of the EM27/SUN deployment and LANL-LDRD 20110081DR for acquisition of the instrument. Jia Chen, Taylor Jones, Jonathan E. Franklin, and Steve Wofsy gratefully acknowledge funding provided by the National Science Foundation through MRI Award 1337512. 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. The January campaign participants are Camille Viatte, Jacob Hedelius, Harrison Parker, Jia Chen, Johnathan Franklin, Taylor Jones, Riley Duren, and Kristal Verhulst. \n\nEdited by: P. Monks. Reviewed by: two anonymous referees\n\nPublished - acp-17-7509-2017.pdf
Supplemental Material - acp-17-7509-2017-supplement.zip
", "abstract": "We estimate the amount of methane (CH_4) emitted by the largest dairies in the southern California region by combining measurements from four mobile solar-viewing ground-based spectrometers (EM27/SUN), in situ isotopic ^(13\u221512)CH_4 measurements from a CRDS analyzer (Picarro), and a high-resolution atmospheric transport simulation with a Weather Research and Forecasting model in large-eddy simulation mode (WRF-LES). \n\nThe remote sensing spectrometers measure the total column-averaged dry-air mole fractions of CH_4 and CO_2 (X_(CH)_4 and X_(CO)_2) in the near infrared region, providing information on total emissions of the dairies at Chino. Differences measured between the four EM27/SUN ranged from 0.2 to 22\u202fppb (part per billion) and from 0.7 to 3\u202fppm (part per million) for X_(CH)_4 and X_(CO)_2, respectively. To assess the fluxes of the dairies, these differential measurements are used in conjunction with the local atmospheric dynamics from wind measurements at two local airports and from the WRF-LES simulations at 111\u202fm resolution. \n\nOur top-down CH_4 emissions derived using the Fourier transform spectrometers (FTS) observations of 1.4 to 4.8\u202fppt\u202fs^(\u22121) are in the low end of previous top-down estimates, consistent with reductions of the dairy farms and urbanization in the domain. However, the wide range of inferred fluxes points to the challenges posed by the heterogeneity of the sources and meteorology. Inverse modeling from WRF-LES is utilized to resolve the spatial distribution of CH_4 emissions in the domain. Both the model and the measurements indicate heterogeneous emissions, with contributions from anthropogenic and biogenic sources at Chino. A Bayesian inversion and a Monte Carlo approach are used to provide the CH_4 emissions of 2.2 to 3.5\u202fppt\u202fs^(\u22121) at Chino.", "date": "2017-06-21", "date_type": "published", "publication": "Atmospheric Chemistry and Physics", "volume": "17", "number": "12", "publisher": "European Geosciences Union", "pagerange": "7509-7528", "id_number": "CaltechAUTHORS:20170807-113657692", "issn": "1680-7324", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170807-113657692", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Keck Institute for Space Studies (KISS)" }, { "agency": "Los Alamos National Laboratory", "grant_number": "20110081DR" }, { "agency": "NSF", "grant_number": "AGS-1337512" }, { "agency": "NASA/JPL/Caltech" } ] }, "local_group": { "items": [ { "id": "Keck-Institute-for-Space-Studies" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/acp-17-7509-2017", "primary_object": { "basename": "acp-17-7509-2017-supplement.zip", "url": "https://authors.library.caltech.edu/records/x56dw-pbr92/files/acp-17-7509-2017-supplement.zip" }, "related_objects": [ { "basename": "acp-17-7509-2017.pdf", "url": "https://authors.library.caltech.edu/records/x56dw-pbr92/files/acp-17-7509-2017.pdf" } ], "resource_type": "article", "pub_year": "2017", "author_list": "Viatte, Camille; Lauvaux, Thomas; et el." }, { "id": "https://authors.library.caltech.edu/records/afgrm-p7v26", "eprint_id": 79079, "eprint_status": "archive", "datestamp": "2023-08-22 01:33:54", "lastmod": "2023-10-26 14:34:45", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Liu-Xiaoxi", "name": { "family": "Liu", "given": "Xiaoxi" }, "orcid": "0000-0002-5104-8886" }, { "id": "Crounse-J-D", "name": { "family": "Crounse", "given": "John D." }, "orcid": "0000-0001-5443-729X" }, { "id": "St-Clair-J-M", "name": { "family": "St. Clair", "given": "Jason M." }, "orcid": "0000-0002-9367-5749" }, { "id": "Teng-Alexander-P", "name": { "family": "Teng", "given": "Alexander P." }, "orcid": "0000-0002-6434-0501" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "Airborne measurements of western U.S. wildfire emissions: Comparison with prescribed burning and air quality implications", "ispublished": "pub", "full_text_status": "public", "keywords": "Wildfire emission; Air quality; Emission factor; Fine particulate matter", "note": "\u00a9 2017 American Geophysical Union. \n\nReceived 6 DEC 2016; Accepted 20 APR 2017; Published online 14 JUN 2017. \n\nThis work was supported by NASA grants NNX12AB77G, NNX15AT90G, NNX12AC06G, and NNX14AP46G-ACCDAM. The BBOP project was funded by U.S. Department of Energy (DOE) Atmospheric Radiation Measurement (ARM) program and the Atmospheric System Research (ASR) program. P.C.J., D.A.D., B.B.P., and J.L.J. were supported by NASA NNX12AC03G and NNX15AT96G. M. M\u00fcller received additional support by the Austrian Space Applications Programme (ASAP 8 and 9, grants 833451 and 840086). ASAP is sponsored by the Austrian Ministry for Transport, Innovation and Technology (BMVIT) and administered by the Aeronautics and Space Agency (ALR) of the Austrian Research Promotion Agency (FFG). The authors would also like to thank the DC-8 and G-1 flight crews. Data from the BBOP and the SEAC4RS missions can be found at http://www.arm.gov/campaigns/bbop and http://www-air.larc.nasa.gov/cgi-bin/ArcView/seac4rs (doi: 10.5067/Aircraft/SEAC4RS/Aerosol-TraceGas-Cloud), respectively. The data generated from this study are available from the authors upon request (greg.huey@eas.gatech.edu).\n\nPublished - Liu_et_al-2017-Journal_of_Geophysical_Research__Atmospheres.pdf
Supplemental Material - jgrd53804-sup-0001-Supplementary.pdf
", "abstract": "Wildfires emit significant amounts of pollutants that degrade air quality. Plumes from three wildfires in the western U.S. were measured from aircraft during the Studies of Emissions and Atmospheric Composition, Clouds and Climate Coupling by Regional Surveys (SEAC^4RS) and the Biomass Burning Observation Project (BBOP), both in summer 2013. This study reports an extensive set of emission factors (EFs) for over 80 gases and 5 components of submicron particulate matter (PM_1) from these temperate wildfires. These include rarely, or never before, measured oxygenated volatile organic compounds and multifunctional organic nitrates. The observed EFs are compared with previous measurements of temperate wildfires, boreal forest fires, and temperate prescribed fires. The wildfires emitted high amounts of PM_1 (with organic aerosol (OA) dominating the mass) with an average EF that is more than 2 times the EFs for prescribed fires. The measured EFs were used to estimate the annual wildfire emissions of carbon monoxide, nitrogen oxides, total nonmethane organic compounds, and PM_1 from 11 western U.S. states. The estimated gas emissions are generally comparable with the 2011 National Emissions Inventory (NEI). However, our PM_1 emission estimate (1530 \u00b1 570 Gg yr^(\u22121)) is over 3 times that of the NEI PM_(2.5) estimate and is also higher than the PM_(2.5) emitted from all other sources in these states in the NEI. This study indicates that the source of OA from biomass burning in the western states is significantly underestimated. In addition, our results indicate that prescribed burning may be an effective method to reduce fine particle emissions.", "date": "2017-06-16", "date_type": "published", "publication": "Journal of Geophysical Research. Atmospheres", "volume": "122", "number": "11", "publisher": "American Geophysical Union", "pagerange": "6108-6129", "id_number": "CaltechAUTHORS:20170713-104419729", "issn": "2169-897X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170713-104419729", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NNX12AB77G" }, { "agency": "NASA", "grant_number": "NNX15AT90G" }, { "agency": "NASA", "grant_number": "NNX12AC06G" }, { "agency": "NASA", "grant_number": "NNX14AP46G-ACCDAM" }, { "agency": "Department of Energy (DOE)" }, { "agency": "NASA", "grant_number": "NNX12AC03G" }, { "agency": "NASA", "grant_number": "NNX15AT96G" }, { "agency": "Austrian Space Applications Programme (ASAP)", "grant_number": "833451" }, { "agency": "Austrian Space Applications Programme (ASAP)", "grant_number": "840086" }, { "agency": "Bundesministerium f\u00fcr Verkehr, Innovation und Technologie (BMVIT)" }, { "agency": "\u00d6sterreichische Forschungsf\u00f6rderungsgesellschaft (FFG)" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1002/2016JD026315", "primary_object": { "basename": "Liu_et_al-2017-Journal_of_Geophysical_Research__Atmospheres.pdf", "url": "https://authors.library.caltech.edu/records/afgrm-p7v26/files/Liu_et_al-2017-Journal_of_Geophysical_Research__Atmospheres.pdf" }, "related_objects": [ { "basename": "jgrd53804-sup-0001-Supplementary.pdf", "url": "https://authors.library.caltech.edu/records/afgrm-p7v26/files/jgrd53804-sup-0001-Supplementary.pdf" } ], "resource_type": "article", "pub_year": "2017", "author_list": "Liu, Xiaoxi; Crounse, John D.; et el." }, { "id": "https://authors.library.caltech.edu/records/k9rp5-6vm11", "eprint_id": 78031, "eprint_status": "archive", "datestamp": "2023-08-22 01:33:14", "lastmod": "2023-10-25 23:40:59", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Kurt\u00e9n-T", "name": { "family": "Kurt\u00e9n", "given": "Theo" }, "orcid": "0000-0002-6416-4931" }, { "id": "M\u00f8ller-K-H", "name": { "family": "M\u00f8ller", "given": "Kristian H." }, "orcid": "0000-0001-8070-8516" }, { "id": "Nguyen-Tran-Bao", "name": { "family": "Nguyen", "given": "Tran Bao" } }, { "id": "Schwantes-R-H", "name": { "family": "Schwantes", "given": "Rebecca H." }, "orcid": "0000-0002-7095-3718" }, { "id": "Misztal-P-K", "name": { "family": "Misztal", "given": "Pawel K." }, "orcid": "0000-0003-1060-1750" }, { "id": "Su-Luping", "name": { "family": "Su", "given": "Luping" } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Fry-J-L", "name": { "family": "Fry", "given": "Juliane L." } }, { "id": "Kj\u00e6rgaard-H-G", "name": { "family": "Kj\u00e6rgaard", "given": "Henrik Grum" }, "orcid": "0000-0002-7275-8297" } ] }, "title": "Alkoxy Radical Bond Scissions Explain the Anomalously Low Secondary Organic Aerosol and Organonitrate Yields from \u03b1-Pinene + NO_3", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2017 American Chemical Society. This is an open access article published under an ACS AuthorChoice License, which permits copying and redistribution of the article or any adaptations for non-commercial purposes. \n\nReceived: April 28, 2017; Accepted: June 6, 2017; Published: June 6, 2017. \n\nFrom the FIXCIT campaign, we thank Matthew Coggon and John Seinfeld for AMS data, Jeong-Hoo Park, Allen Goldstein, John Mak, and Alex Guenther for the PTR-MS data, John Crounse, Alex Teng and Kelvin Bates for the ToF-CIMS data and their work organizing and conducting the experiment. We also thank Alan Shusterman, Catherine Neshyba, Katie Stellmach, Rasmus V. Otkj\u00e6r, Noora Hyttinen, Camilla Mia Tram, and Benjamin N. Frandsen for helpful discussions. TK thanks the Academy of Finland (266388) for funding and the CSC IT Center for Science in Espoo, Finland, for computing time. HGK and KHM thank the Center for Exploitation of Solar Energy, University of Copenhagen and the Danish Center for Scientific Computing for funding. POW thanks the NSF for funding (Grant No. CHE-1508526 and AGS-1240604). JLF gratefully acknowledges sabbatical support from the U.S. Fulbright Scholar Program and research funding from the NOAA Climate Program Office's AC4 program (Grant\nNo. NA13OAR4310070). The National Center for Atmospheric Research is sponsored by the National Science Foundation.\n\nPublished - acs.jpclett.7b01038.pdf
Supplemental Material - jz7b01038_si_001.pdf
Supplemental Material - jz7b01038_si_002.zip
", "abstract": "Oxidation of monoterpenes (C_(10)H_(16)) by nitrate radicals (NO_3) constitutes an important source of atmospheric secondary organic aerosol (SOA) and organonitrates. However, knowledge of the mechanisms of their formation is incomplete and differences in yields between similar monoterpenes are poorly understood. In particular, yields of SOA and organonitrates from \u03b1-pinene + NO_3 are low, while those from \u0394^3-carene + NO_3 are high. Using computational methods, we suggest that bond scission of the nitrooxy alkoxy radicals from \u0394^3-carene lead to the formation of reactive keto-nitrooxy-alkyl radicals, which retain the nitrooxy moiety and can undergo further reactions to form SOA. In contrast, bond scissions of the nitrooxy alkoxy radicals from \u03b1-pinene lead almost exclusively to the formation of the relatively unreactive and volatile product pinonaldehyde (C_(10)H_(16)O_2), thereby limiting organonitrate and SOA formation. This hypothesis is supported by laboratory experiments that quantify products of the reaction of \u03b1-pinene + NO_3 under atmospherically relevant conditions.", "date": "2017-06-06", "date_type": "published", "publication": "Journal of Physical Chemistry Letters", "volume": "2017", "number": "8", "publisher": "American Chemical Society", "pagerange": "2826-2834", "id_number": "CaltechAUTHORS:20170608-112307794", "issn": "1948-7185", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170608-112307794", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Academy of Finland", "grant_number": "266388" }, { "agency": "University of Copenhagen" }, { "agency": "Danish Center for Scientific Computing" }, { "agency": "NSF", "grant_number": "CHE-1508526" }, { "agency": "NSF", "grant_number": "AGS-1240604" }, { "agency": "Fulbright Foundation" }, { "agency": "National Oceanic and Atmospheric Administration (NOAA)", "grant_number": "NA13OAR4310070" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1021/acs.jpclett.7b01038", "primary_object": { "basename": "acs.jpclett.7b01038.pdf", "url": "https://authors.library.caltech.edu/records/k9rp5-6vm11/files/acs.jpclett.7b01038.pdf" }, "related_objects": [ { "basename": "jz7b01038_si_001.pdf", "url": "https://authors.library.caltech.edu/records/k9rp5-6vm11/files/jz7b01038_si_001.pdf" }, { "basename": "jz7b01038_si_002.zip", "url": "https://authors.library.caltech.edu/records/k9rp5-6vm11/files/jz7b01038_si_002.zip" } ], "resource_type": "article", "pub_year": "2017", "author_list": "Kurt\u00e9n, Theo; M\u00f8ller, Kristian H.; et el." }, { "id": "https://authors.library.caltech.edu/records/r5keg-yx461", "eprint_id": 85565, "eprint_status": "archive", "datestamp": "2023-08-22 01:32:43", "lastmod": "2023-10-18 18:19:57", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Wunch-D", "name": { "family": "Wunch", "given": "Debra" }, "orcid": "0000-0002-4924-0377" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Osterman-G-B", "name": { "family": "Osterman", "given": "Gregory" } }, { "id": "Fisher-B-M", "name": { "family": "Fisher", "given": "Brendan" } }, { "id": "Naylor-B-J", "name": { "family": "Naylor", "given": "Bret" } }, { "id": "Roehl-C-M", "name": { "family": "Roehl", "given": "Coleen M." }, "orcid": "0000-0001-5383-8462" }, { "id": "Mandrake-L", "name": { "family": "Mandrake", "given": "Lukas" } }, { "id": "Viatte-C", "name": { "family": "Viatte", "given": "Camille" } }, { "id": "Kiel-M", "name": { "family": "Kiel", "given": "Matth\u00e4us" }, "orcid": "0000-0002-9784-962X" }, { "id": "Gunson-M-R", "name": { "family": "Gunson", "given": "Michael R." } }, { "id": "Crisp-D", "name": { "family": "Crisp", "given": "David" }, "orcid": "0000-0002-4573-9998" }, { "id": "Eldering-A", "name": { "family": "Eldering", "given": "Annmarie" }, "orcid": "0000-0003-1080-9922" } ] }, "title": "Comparisons of the Orbiting Carbon Observatory-2 (OCO-2) X_(CO_2) measurements with TCCON", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2017 Author(s). This work is distributed under the Creative Commons Attribution 3.0 License. \n\nReceived: 06 Jul 2016 \u2013 Discussion started: 29 Aug 2016. Revised: 12 Apr 2017 \u2013 Accepted: 30 Apr 2017 \u2013 Published: 13 Jun 2017. \n\nPart of this work was performed at the Jet Propulsion Laboratory, California Institute of Technology, under contract with NASA. The operation of the Ascension Island site was funded by the Max Planck Society. The Bremen, Bia\u0142ystok, and Orl\u00e9ans TCCON sites are funded by the EU projects InGOS and ICOS-INWIRE as well as by the Senate of Bremen. The Darwin and Wollongong TCCON sites are funded by NASA grants NAG512247 and NNG05GD07G and by Australian Research Council grants DP140101552, DP110103118, DP0879468, LE0668470, and LP0562346. We are grateful to the DOE ARM program for technical support at the Darwin TCCON site. Nicholas M. Deutscher was supported by an Australian Research Council fellowship, DE140100178. The TCCON site at R\u00e9union Island is operated by the Royal Belgian Institute for Space Aeronomy with financial support in 2014, 2015, and 2016 under the EU project ICOS-Inwire and the ministerial decree for ICOS (FR/35/IC2) and local activities supported by LACy/UMR8105 \u2013 Universit\u00e9 de La R\u00e9union. TCCON is funded by NASA grants NNX14AI60G, NNX11AG01G, NAG5-12247, NNG05-GD07G, and NASA's Orbiting Carbon Observatory Program. We are grateful to the DOE ARM program for technical support in Lamont and Jeff Ayers for technical support in Park Falls. From 2004 to 2011 the Lauder TCCON program was funded by the New Zealand Foundation of Research Science and Technology contracts CO1X0204, CO1X0703, and CO1X0406. Since 2011 the program has been funded by NIWA's Atmosphere Research Programme 3 (2011/13 Statement of Corporate Intent). The TCCON measurements at Eureka are made by the Canadian Network for the Detection of Atmospheric Change (CANDAC), led by James R. Drummond, and in part by the Canadian Arctic ACE Validation Campaigns, led by Kaley A. Walker. They are supported by the Atlantic Innovation Fund/Nova Scotia Research Innovation Trust, Canada Foundation for Innovation, Canadian Foundation for Climate and Atmospheric Sciences, Canadian Space Agency, Environment Canada, Government of Canada International Polar Year funding, Natural Sciences and Engineering Research Council, Northern Scientific Training Program, Ontario Innovation Trust, and Ontario Research Fund and Polar Continental Shelf Program. \n\nWe thank PEARL site manager Pierre Fogal, the staff at the Eureka weather station, and the CANDAC operators for the logistical and on-site support provided at Eureka. Manvendra K. Dubey thanks DOE OBER's TES and NGEE-Tropics program for funding and ARM for logistical support of the TCCON deployment during the GoAmazon campaign.\n\nAuthor contributions. Debra Wunch wrote the manuscript and produced the main analysis and results with significant input from Gregory Osterman, Camille Viatte, and Paul O. Wennberg. Debra Wunch, Gregory Osterman, Brendan Fisher, Matth\u00e4us Kiel, Bret Naylor, Coleen M. Roehl, Christopher O'Dell, Annmarie Eldering, Lukas Mandrake, Camille Viatte, Michael R. Gunson, David Crisp, and Paul O. Wennberg contributed to the experiment design and analysis of data. David W. T. Griffith, Nicholas M. Deutscher, Voltaire A. Velazco, Justus Notholt, Thorsten Warneke, Christof Petri, Martine De Maziere, Mahesh K. Sha, Ralf Sussmann, Markus Rettinger, David Pollard, John Robinson, Isamu Morino, Osamu Uchino, Frank Hase, Thomas Blumenstock, Matth\u00e4us Kiel, Dietrich G. Feist, Sabrina G. Arnold, Kimberly Strong, Joseph Mendonca, Rigel Kivi, Pauli Heikkinen, Laura Iraci, James Podolske, Patrick W. Hillyard, Shuji Kawakami, Manvendra K. Dubey, Harrison A. Parker, Eliezer Sepulveda, Omaira E. Garc\u00eda, Yao Te, and Pascal Jeseck provided TCCON data. All authors read and provided comments on the manuscript. \n\nThe authors declare that they have no conflict of interest.\n\nPublished - amt-10-2209-2017.pdf
", "abstract": "NASA's Orbiting Carbon Observatory-2 (OCO-2) has been measuring carbon dioxide column-averaged dry-air mole fraction, X_(CO_2), in the Earth's atmosphere for over 2 years. In this paper, we describe the comparisons between the first major release of the OCO-2 retrieval algorithm (B7r) and X_(CO2) from OCO-2's primary ground-based validation network: the Total Carbon Column Observing Network (TCCON). The OCO-2 X_(CO_2) retrievals, after filtering and bias correction, agree well when aggregated around and coincident with TCCON data in nadir, glint, and target observation modes, with absolute median differences less than 0.4\u202fppm and RMS differences less than 1.5\u202fppm. After bias correction, residual biases remain. These biases appear to depend on latitude, surface properties, and scattering by aerosols. It is thus crucial to continue measurement comparisons with TCCON to monitor and evaluate the OCO-2 X_(CO_2) data quality throughout its mission.", "date": "2017-06", "date_type": "published", "publication": "Atmospheric Measurement Techniques", "volume": "10", "number": "6", "publisher": "European Geosciences Union", "pagerange": "2209-2238", "id_number": "CaltechAUTHORS:20180402-132028732", "issn": "1867-1381", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180402-132028732", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA/JPL/Caltech" }, { "agency": "Max Planck Society" }, { "agency": "European Union" }, { "agency": "Senate of Bremen" }, { "agency": "NASA", "grant_number": "NAG512247" }, { "agency": "NASA", "grant_number": "NNG05GD07G" }, { "agency": "Australian Research Council", "grant_number": "DP140101552" }, { "agency": "Australian Research Council", "grant_number": "DP110103118" }, { "agency": "Australian Research Council", "grant_number": "DP0879468" }, { "agency": "Australian Research Council", "grant_number": "LE0668470" }, { "agency": "Australian Research Council", "grant_number": "LP0562346" }, { "agency": "Australian Research Council", "grant_number": "DE140100178" }, { "agency": "Universit\u00e9 de La R\u00e9union" }, { "agency": "NASA", "grant_number": "NNX14AI60G" }, { "agency": "NASA", "grant_number": "NNX11AG01G" }, { "agency": "NASA", "grant_number": "NAG5-12247" }, { "agency": "NASA", "grant_number": "NNG05-GD07G" }, { "agency": "NASA Orbiting Carbon Observatory" }, { "agency": "New Zealand Foundation of Research Science and Technology", "grant_number": "CO1X0204" }, { "agency": "New Zealand Foundation of Research Science and Technology", "grant_number": "CO1X0703" }, { "agency": "New Zealand Foundation of Research Science and Technology", "grant_number": "CO1X0406" }, { "agency": "National Institute of Water and Atmospheric Research (NIWA)" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/amt-10-2209-2017", "primary_object": { "basename": "amt-10-2209-2017.pdf", "url": "https://authors.library.caltech.edu/records/r5keg-yx461/files/amt-10-2209-2017.pdf" }, "resource_type": "article", "pub_year": "2017", "author_list": "Wunch, Debra; Wennberg, Paul O.; et el." }, { "id": "https://authors.library.caltech.edu/records/hd4p3-6xe20", "eprint_id": 76636, "eprint_status": "archive", "datestamp": "2023-08-22 01:31:20", "lastmod": "2023-10-25 16:10:34", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Turner-Alexander-J", "name": { "family": "Turner", "given": "Alexander J." }, "orcid": "0000-0003-1406-7372" }, { "id": "Frankenberg-C", "name": { "family": "Frankenberg", "given": "Christian" }, "orcid": "0000-0002-0546-5857" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Jacob-Daniel-J", "name": { "family": "Jacob", "given": "Daniel J." }, "orcid": "0000-0002-6373-3100" } ] }, "title": "Ambiguity in the causes for decadal trends in atmospheric methane and hydroxyl", "ispublished": "pub", "full_text_status": "public", "keywords": "methane; renewed growth; hydroxyl; oxidative capacity; troposphere", "note": "\u00a9 2017 National Academy of Sciences. Freely available online through the PNAS open access option. \n\nEdited by Mark H. Thiemens, University of California, San Diego, La Jolla, CA, and approved December 28, 2016 (received for review September 26, 2016). Published online before print April 17, 2017. \n\nWe thank E. Dlugokencky for providing methane data; S. Montzka, R. Prinn, S. O'Doherty, and R. Weiss for providing MCF data; and I. Levin, C. Veidt, B. Vaughn, J. White, and S. Englund for providing \u03b4^(13)CH_4 data. This work was supported by a Department of Energy Computational Science Graduate Fellowship (to A.J.T.) and by a NASA Carbon Monitoring System grant (to D.J.J.). \n\nAuthor contributions: A.J.T. and C.F. designed research; A.J.T. and C.F. performed research; A.J.T. contributed new reagents/analytic tools; A.J.T., C.F., P.O.W., and D.J.J. analyzed data; and A.J.T., C.F., P.O.W., and D.J.J. wrote the paper. \n\nThe authors declare no conflict of interest. \n\nThis article is a PNAS Direct Submission. \n\nData deposition: The model and data reported in this paper have been deposited in GitHub, https://github.com/alexjturner/BoxModel_PNAS_20161223. \n\nThis article contains supporting information online at www.pnas.org/lookup/suppl/doi:10.1073/pnas.1616020114/-/DCSupplemental.\n\nPublished - PNAS-2017-Turner-5367-72.pdf
Supplemental Material - pnas.1616020114.sapp.pdf
", "abstract": "Methane is the second strongest anthropogenic greenhouse gas and its atmospheric burden has more than doubled since 1850. Methane concentrations stabilized in the early 2000s and began increasing again in 2007. Neither the stabilization nor the recent growth are well understood, as evidenced by multiple competing hypotheses in recent literature. Here we use a multispecies two-box model inversion to jointly constrain 36 y of methane sources and sinks, using ground-based measurements of methane, methyl chloroform, and the C^(13)/C^(12) ratio in atmospheric methane (\u03b4^(13)CH_4) from 1983 through 2015. We find that the problem, as currently formulated, is underdetermined and solutions obtained in previous work are strongly dependent on prior assumptions. Based on our analysis, the mathematically most likely explanation for the renewed growth in atmospheric methane, counterintuitively, involves a 25-Tg/y decrease in methane emissions from 2003 to 2016 that is offset by a 7% decrease in global mean hydroxyl (OH) concentrations, the primary sink for atmospheric methane, over the same period. However, we are still able to fit the observations if we assume that OH concentrations are time invariant (as much of the previous work has assumed) and we then find solutions that are largely consistent with other proposed hypotheses for the renewed growth of atmospheric methane since 2007. We conclude that the current surface observing system does not allow unambiguous attribution of the decadal trends in methane without robust constraints on OH variability, which currently rely purely on methyl chloroform data and its uncertain emissions estimates.", "date": "2017-05-23", "date_type": "published", "publication": "Proceedings of the National Academy of Sciences of the United States of America", "volume": "114", "number": "21", "publisher": "National Academy of Sciences", "pagerange": "5367-5372", "id_number": "CaltechAUTHORS:20170418-113144693", "issn": "0027-8424", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170418-113144693", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)" }, { "agency": "NASA" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1073/pnas.1616020114", "pmcid": "PMC5448216", "primary_object": { "basename": "pnas.1616020114.sapp.pdf", "url": "https://authors.library.caltech.edu/records/hd4p3-6xe20/files/pnas.1616020114.sapp.pdf" }, "related_objects": [ { "basename": "PNAS-2017-Turner-5367-72.pdf", "url": "https://authors.library.caltech.edu/records/hd4p3-6xe20/files/PNAS-2017-Turner-5367-72.pdf" } ], "resource_type": "article", "pub_year": "2017", "author_list": "Turner, Alexander J.; Frankenberg, Christian; et el." }, { "id": "https://authors.library.caltech.edu/records/xq7ny-p9y06", "eprint_id": 90302, "eprint_status": "archive", "datestamp": "2023-08-22 01:30:18", "lastmod": "2023-10-18 23:21:34", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Hedelius-J-K", "name": { "family": "Hedelius", "given": "Jacob K." }, "orcid": "0000-0003-2025-7519" }, { "id": "Parker-H", "name": { "family": "Parker", "given": "Harrison" } }, { "id": "Wunch-D", "name": { "family": "Wunch", "given": "Debra" }, "orcid": "0000-0002-4924-0377" }, { "id": "Roehl-C-M", "name": { "family": "Roehl", "given": "Coleen M." }, "orcid": "0000-0001-5383-8462" }, { "id": "Viatte-C", "name": { "family": "Viatte", "given": "Camille" } }, { "id": "Newman-S", "name": { "family": "Newman", "given": "Sally" }, "orcid": "0000-0003-0710-995X" }, { "id": "Toon-G-C", "name": { "family": "Toon", "given": "Geoffrey C." }, "orcid": "0000-0003-4174-7541" }, { "id": "Podolske-J-R", "name": { "family": "Podolske", "given": "James R." } }, { "id": "Hillyard-P-W", "name": { "family": "Hillyard", "given": "Patrick W." } }, { "id": "Iraci-L-T", "name": { "family": "Iraci", "given": "Laura T." }, "orcid": "0000-0002-2859-5259" }, { "id": "Dubey-M-K", "name": { "family": "Dubey", "given": "Manvendra K." } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "Intercomparability of X_(CO_2) and X_(CH_4) from the United States TCCON sites", "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: 25 Aug 2016 \u2013 Discussion started: 15 Sep 2016 \u2013 Revised: 04 Mar 2017 \u2013 Accepted: 24 Mar 2017 \u2013 Published: 20 Apr 2017. \n\nThe MODIS Vegetation Indices products were retrieved from the online Data Pool, courtesy of the NASA EOSDIS Land Processes Distributed Active Archive Center (LP DAAC), USGS/Earth Resources Observation and Science (EROS) Center, Sioux Falls, South Dakota (https://lpdaac.usgs.gov/node/843). The nightlight data products (version 1 Nighttime VIIRS Day/Night Band composites) are generated by the Earth Observation Group, NOAA National Geophysical Data Center (http://ngdc.noaa.gov/eog/viirs/download_monthly.html). Ancillary surface meteorological data at Lamont were obtained from the Atmospheric Radiation Measurement (ARM) Program sponsored by the US Department of Energy, Office of Science, Office of Biological and Environmental Research, Climate and Environmental Sciences Division (Kyrouac and Holdridge, 1993). ERA-Interim data were supplied by ECMWF (European Centre for Medium-Range Weather Forecasts; http://www.ecmwf.int/). NAM12 (North American Mesoscale Forecast System, 12 km) data are a product of NOAA (NCEI DSI 6173,\ngov.noaa.ncdc: C00630). \n\nThere are numerous people we wish to thank: Gregor Surawicz and Bruker Optics for assistance with the EM27/SUN firmware update; Matthias Frey for helpful discussions; Matthaeus Kiel for discussions on the air-mass-dependent correction factor; Heidi Boyden for her assistance at AFRC; Jeff Ayers for his on-site assistance at Park Falls; ARM SGP site for accommodations and Patrick Dowell and Kenneth Teske for their on-site assistance; Chris O'Dell for providing pTz profiles from MERRA-2 and GEOS5; and David Pollard\nfor analysis of unassimilated sonde profiles. \n\nThe authors gratefully acknowledge funding from the NASA Carbon Cycle Science program (grant number NNX14AI60G) and the Jet Propulsion Laboratory. Manvendra K. Dubey acknowledges funding from the NASA-CMS program for field observations and from the LANL-LDRD for the acquisition of the LANL EM27/SUN. \n\nThe authors thank the referees for their comments. \n\nEdited by: J. Notholt. Reviewed by: F. Hase and one anonymous referee \n\nData availability. TCCON data are currently hosted on the CDIAC and will also be available on the Caltech library data archive by the end of the year (Iraci et al., 2014; Wennberg et al., 2014a, b, c). Mobile FTS data are available upon request to the authors. \n\nThe authors declare that they have no conflict of interest.\n\nPublished - amt-10-1481-2017.pdf
", "abstract": "The Total Carbon Column Observing Network (TCCON) has become the standard for long-term column-averaged measurements of CO_2 and CH_4. Here, we use a pair of portable spectrometers to test for intra-network bias among the four currently operating TCCON sites in the United States (US). A previous analytical error analysis has suggested that the maximum 2\u03c3 site-to-site relative (absolute) bias of TCCON should be less than 0.2% (0.8ppm) in X_(CO_2) and 0.4% (7ppb) in X_(CH_4). We find here experimentally that the 95% confidence intervals for maximum pairwise site-to-site bias among the four US TCCON sites are 0.05\u20130.14% for X_(CO_2) and 0.08\u20130.24% for X_(CH_4). This is close to the limit of the bias we can detect using this methodology.", "date": "2017-04-20", "date_type": "published", "publication": "Atmospheric Measurement Techniques", "volume": "10", "number": "4", "publisher": "European Geosciences Union", "pagerange": "1481-1493", "id_number": "CaltechAUTHORS:20181016-153903856", "issn": "1867-1381", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20181016-153903856", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NNX14AI60G" }, { "agency": "JPL" }, { "agency": "Los Alamos National Laboratory" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/amt-10-1481-2017", "primary_object": { "basename": "amt-10-1481-2017.pdf", "url": "https://authors.library.caltech.edu/records/xq7ny-p9y06/files/amt-10-1481-2017.pdf" }, "resource_type": "article", "pub_year": "2017", "author_list": "Hedelius, Jacob K.; Parker, Harrison; et el." }, { "id": "https://authors.library.caltech.edu/records/k7t26-hba31", "eprint_id": 76536, "eprint_status": "archive", "datestamp": "2023-08-22 01:30:12", "lastmod": "2023-10-25 16:05:31", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Teng-Alexander-P", "name": { "family": "Teng", "given": "Alexander P." }, "orcid": "0000-0002-6434-0501" }, { "id": "Crounse-J-D", "name": { "family": "Crounse", "given": "John D." }, "orcid": "0000-0001-5443-729X" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "Isoprene Peroxy Radical Dynamics", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2017 American Chemical Society. \n\nReceived 14 December 2016. Published online 11 April 2017. \n\nWe thank the National Science Foundation (AGS-1240604 and CHE-1508526) and the National Aeronautics and Space Administration (NNX14AP46G) for supporting this work. Discussions with our Caltech colleagues and with Jozef Peeters were helpful in the analysis. We thank Frank Keutsch and Jean Rivera for the 1-OH, 2-OOH ISOPOOH used to estimate the rate of oxygen dissociation from the 1,2-hydroxyperoxy radical, and Henrik Kjaergaard for dipole moment calculations. We thank the anonymous reviewers for their critical comments that improved this manuscript. \n\nThe authors declare no competing financial interest.\n\nSupplemental Material - ja6b12838_si_001.pdf
", "abstract": "Approximately 500 Tg of 2-methyl-1,3-butadiene (isoprene) is emitted by deciduous trees each year. Isoprene oxidation in the atmosphere is initiated primarily by addition of hydroxyl radicals (OH) to C_4 or C_1 in a ratio 0.57 \u00b1 0.03 (1\u03c3) to produce two sets of distinct allylic radicals. Oxygen (O_2) adds to these allylic radicals either \u03b4 (Z or E depending on whether the allylic radical is cis or trans) or \u03b2 to the OH group forming six distinct peroxy radical isomers. Due to the enhanced stability of the allylic radical, however, these peroxy radicals lose O_2 in competition with bimolecular reactions. In addition, the Z-\u03b4 hydroxy peroxy radical isomers undergo unimolecular 1,6 H-shift isomerization. Here, we use isomer-resolved measurements of the reaction products of the peroxy radicals to diagnose this complex chemistry. We find that the ratio of \u03b4 to \u03b2 hydroxy peroxy radicals depends on their bimolecular lifetime (\u03c4_(bimolecular)). At \u03c4_(bimolecular) \u2248 0.1 s, a transition occurs from a kinetically to a largely thermodynamically controlled distribution at 297 K. Thus, in nature, where \u03c4_(bimolecular) > 10 s, the distribution of isoprene hydroxy peroxy radicals will be controlled primarily by the difference in the relative stability of the peroxy radical isomers. In this regime, \u03b2 hydroxy peroxy radical isomers comprise \u223c95% of the radical pool, a much higher fraction than in the nascent (kinetic) distribution. Intramolecular 1,6 H-shift isomerization of the Z-\u03b4 hydroxy peroxy radical isomers produced from OH addition to C_4 is estimated to be \u223c4 s^(\u20131) at 297 K. While the Z-\u03b4 isomer is initially produced in low yield, it is continually reformed via decomposition of the \u03b2 hydroxy peroxy radicals. As a result, unimolecular chemistry from this isomer contributes about half of the atmospheric fate of the entire pool of peroxy radicals formed via addition of OH at C_4 for typical atmospheric conditions (\u03c4_(bimolecular) = 100 s and T = 25 C). In contrast, unimolecular chemistry following OH addition at C_1 is slower and less important.", "date": "2017-04-19", "date_type": "published", "publication": "Journal of the American Chemical Society", "volume": "139", "number": "15", "publisher": "American Chemical Society", "pagerange": "5367-5377", "id_number": "CaltechAUTHORS:20170412-112409065", "issn": "0002-7863", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170412-112409065", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "AGS-1240604" }, { "agency": "NSF", "grant_number": "CHE-1508526" }, { "agency": "NASA", "grant_number": "NNX14AP46G" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1021/jacs.6b12838", "primary_object": { "basename": "ja6b12838_si_001.pdf", "url": "https://authors.library.caltech.edu/records/k7t26-hba31/files/ja6b12838_si_001.pdf" }, "resource_type": "article", "pub_year": "2017", "author_list": "Teng, Alexander P.; Crounse, John D.; et el." }, { "id": "https://authors.library.caltech.edu/records/kqh5k-hzp92", "eprint_id": 77382, "eprint_status": "archive", "datestamp": "2023-08-22 01:29:18", "lastmod": "2023-10-25 22:59:02", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Zeng-Zhao-Cheng", "name": { "family": "Zeng", "given": "Zhao-Cheng" }, "orcid": "0000-0002-0008-6508" }, { "id": "Lei-Liping", "name": { "family": "Lei", "given": "Liping" } }, { "id": "Strong-K", "name": { "family": "Strong", "given": "Kimberly" } }, { "id": "Jones-D-B-A", "name": { "family": "Jones", "given": "Dylan B. A." } }, { "id": "Guo-Lijie", "name": { "family": "Guo", "given": "Lijie" } }, { "id": "Liu-Min", "name": { "family": "Liu", "given": "Min" } }, { "id": "Deng-Feng", "name": { "family": "Deng", "given": "Feng" }, "orcid": "0000-0002-1381-0243" }, { "id": "Deutscher-N-M", "name": { "family": "Deutscher", "given": "Nicholas M." }, "orcid": "0000-0002-2906-2577" }, { "id": "Dubey-M-K", "name": { "family": "Dubey", "given": "Manvendra K." } }, { "id": "Griffith-D-W-T", "name": { "family": "Griffith", "given": "David W. T." }, "orcid": "0000-0002-7986-1924" }, { "id": "Hase-F", "name": { "family": "Hase", "given": "Frank" } }, { "id": "Henderson-B", "name": { "family": "Henderson", "given": "Bradley" } }, { "id": "Kivi-R", "name": { "family": "Kivi", "given": "Rigel" } }, { "id": "Lindenmaier-R", "name": { "family": "Lindenmaier", "given": "Rodica" } }, { "id": "Morino-Isamu", "name": { "family": "Morino", "given": "Isamu" }, "orcid": "0000-0003-2720-1569" }, { "id": "Notholt-J", "name": { "family": "Notholt", "given": "Justus" } }, { "id": "Ohyama-H", "name": { "family": "Ohyama", "given": "Hirofumi" } }, { "id": "Petri-C", "name": { "family": "Petri", "given": "Christof" }, "orcid": "0000-0002-7010-5532" }, { "id": "Sussmann-R", "name": { "family": "Sussmann", "given": "Ralf" } }, { "id": "Velazco-V-A", "name": { "family": "Velazco", "given": "Voltaire A." }, "orcid": "0000-0002-1376-438X" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Lin-Hui", "name": { "family": "Lin", "given": "Hui" } } ] }, "title": "Global land mapping of satellite-observed CO_2 total columns using spatio-temporal geostatistics", "ispublished": "pub", "full_text_status": "public", "keywords": "XCO_2, ACOS-GOSAT, Spatio-temporal geostatistics, global mapping, geospatial dataset", "note": "\u00a9 2017 Taylor & Francis. \n\nReceived 19 Oct 2015, Accepted 17 Feb 2016, Published online: 14 Apr 2016.", "abstract": "This study presents an approach for generating a global land mapping dataset of the satellite measurements of CO_2 total column (XCO_2) using spatio-temporal geostatistics, which makes full use of the joint spatial and temporal dependencies between observations. The mapping approach considers the latitude-zonal seasonal cycles and spatio-temporal correlation structure of XCO2, and obtains global land maps of XCO_2, with a spatial grid resolution of 1\u00b0 latitude by 1\u00b0 longitude and temporal resolution of 3 days. We evaluate the accuracy and uncertainty of the mapping dataset in the following three ways: (1) in cross-validation, the mapping approach results in a high correlation coefficient of 0.94 between the predictions and observations, (2) in comparison with ground truth provided by the Total Carbon Column Observing Network (TCCON), the predicted XCO_2 time series and those from TCCON sites are in good agreement, with an overall bias of 0.01 ppm and a standard deviation of the difference of 1.22 ppm and (3) in comparison with model simulations, the spatio-temporal variability of XCO_2 between the mapping dataset and simulations from the CT2013 and GEOS-Chem are generally consistent. The generated mapping XCO_2 data in this study provides a new global geospatial dataset in global understanding of greenhouse gases dynamics and global warming.", "date": "2017-04", "date_type": "published", "publication": "International Journal of Digital Earth", "volume": "10", "number": "4", "publisher": "Taylor & Francis", "pagerange": "426-456", "id_number": "CaltechAUTHORS:20170511-153055961", "issn": "1753-8947", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170511-153055961", "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": "10.1080/17538947.2016.1156777", "resource_type": "article", "pub_year": "2017", "author_list": "Zeng, Zhao-Cheng; Lei, Liping; et el." }, { "id": "https://authors.library.caltech.edu/records/4kya4-sc541", "eprint_id": 75839, "eprint_status": "archive", "datestamp": "2023-08-19 01:59:36", "lastmod": "2023-10-20 23:28:18", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Schwantes-R-H", "name": { "family": "Schwantes", "given": "Rebecca H." }, "orcid": "0000-0002-7095-3718" }, { "id": "Schilling-K-A", "name": { "family": "Schilling", "given": "Katherine A." } }, { "id": "McVay-R-C", "name": { "family": "McVay", "given": "Renee C." }, "orcid": "0000-0001-7766-5009" }, { "id": "Lignell-H", "name": { "family": "Lignell", "given": "Hanna" }, "orcid": "0000-0001-7049-1659" }, { "id": "Coggon-M-M", "name": { "family": "Coggon", "given": "Matthew M." }, "orcid": "0000-0002-5763-1925" }, { "id": "Zhang-Xuan", "name": { "family": "Zhang", "given": "Xuan" } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Seinfeld-J-H", "name": { "family": "Seinfeld", "given": "John H." }, "orcid": "0000-0003-1344-4068" } ] }, "title": "Formation of highly oxygenated low-volatility products from cresol oxidation", "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: 04 Oct 2016 \u2013 Discussion started: 10 Oct 2016. Revised: 23 Jan 2017 \u2013 Accepted: 15 Feb 2017 \u2013 Published: 10 Mar 2017. \n\nData availability: Data used within this work are available upon request. Please email Rebecca Schwantes (rschwant@ucar.edu). \n\nThe Supplement related to this article is available online at doi:10.5194/acp-17-3453-2017-supplement. \n\nThis work was supported by National Science Foundation grants AGS-1240604 and AGS-1523500. We thank Hannah Allen and Anke Noelscher for their experimental assistance and Nathan Dalleska and John Crounse for helpful discussions. The National Center for Atmospheric Research is sponsored by the National Science Foundation. \n\nEdited by: Y. Rudich. Reviewed by: H. Herrmann and T. Mentel. \n\nThe authors declare that they have no conflict of interest.\n\nPublished - acp-17-3453-2017.pdf
Supplemental Material - acp-17-3453-2017-supplement.pdf
", "abstract": "Hydroxyl radical (OH) oxidation of toluene produces ring-retaining products: cresol and benzaldehyde, and ring-opening products: bicyclic intermediate compounds and epoxides. Here, first- and later-generation OH oxidation products from cresol and benzaldehyde are identified in laboratory chamber experiments. For benzaldehyde, first-generation ring-retaining products are identified, but later-generation products are not detected. For cresol, low-volatility (saturation mass concentration, C*\u2009\u223c\u20093.5\u202f\u2009\u00d7\u2009\u202f10^4\u202f\u2212\u202f7.7\u202f\u2009\u00d7\u2009\u202f10^(\u22123)\u202f\u00b5g\u202fm^(\u22123)), first- and later-generation ring-retaining products are identified. Subsequent OH addition to the aromatic ring of o-cresol leads to compounds such as hydroxy, dihydroxy, and trihydroxy methyl benzoquinones and dihydroxy, trihydroxy, tetrahydroxy, and pentahydroxy toluenes. These products are detected in the gas phase by chemical ionization mass spectrometry (CIMS) and in the particle phase using offline direct analysis in real-time mass spectrometry (DART-MS). Our data suggest that the yield of trihydroxy toluene from dihydroxy toluene is substantial. While an exact yield cannot be reported as authentic standards are unavailable, we find that a yield for trihydroxy toluene from dihydroxy toluene of \u223c\u20090.7 (equal to the reported yield of dihydroxy toluene from o-cresol; Olariu et al., 2002) is consistent with experimental results for o-cresol oxidation under low-NO conditions. These results suggest that even though the cresol pathway accounts for only \u223c\u200920\u202f% of the oxidation products of toluene, it is the source of a significant fraction (\u223c\u200920\u201340\u202f%) of toluene secondary organic aerosol (SOA) due to the formation of low-volatility products.", "date": "2017-03-10", "date_type": "published", "publication": "Atmospheric Chemistry and Physics", "volume": "17", "number": "5", "publisher": "European Geosciences Union", "pagerange": "3453-3474", "id_number": "CaltechAUTHORS:20170407-102119598", "issn": "1680-7324", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170407-102119598", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "AGS-1240604" }, { "agency": "NSF", "grant_number": "AGS-1523500" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/acp-17-3453-2017", "primary_object": { "basename": "acp-17-3453-2017.pdf", "url": "https://authors.library.caltech.edu/records/4kya4-sc541/files/acp-17-3453-2017.pdf" }, "related_objects": [ { "basename": "acp-17-3453-2017-supplement.pdf", "url": "https://authors.library.caltech.edu/records/4kya4-sc541/files/acp-17-3453-2017-supplement.pdf" } ], "resource_type": "article", "pub_year": "2017", "author_list": "Schwantes, Rebecca H.; Schilling, Katherine A.; et el." }, { "id": "https://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.edu/records/e1afe-mc689", "eprint_id": 85134, "eprint_status": "archive", "datestamp": "2023-08-22 19:39:03", "lastmod": "2023-10-18 17:54:23", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Eldering-A", "name": { "family": "Eldering", "given": "Annmarie" }, "orcid": "0000-0003-1080-9922" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Viatte-C", "name": { "family": "Viatte", "given": "Camille" } }, { "id": "Frankenberg-C", "name": { "family": "Frankenberg", "given": "Christian" }, "orcid": "0000-0002-0546-5857" }, { "id": "Roehl-C-M", "name": { "family": "Roehl", "given": "Coleen M." }, "orcid": "0000-0001-5383-8462" }, { "id": "Wunch-D", "name": { "family": "Wunch", "given": "Debra" }, "orcid": "0000-0002-4924-0377" } ] }, "title": "The Orbiting Carbon Observatory-2: first 18 months of science data products", "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: 21 July 2016. Discussion started: 23 September 2016 Revised: 13 January 2017. Accepted: 15 January 2017. Published: 15 February 2017. \n\nPart of this work was conducted at the Jet Propulsion Laboratory, California Institute of Technology, under contract with the National Aeronautics and Space Administration (NASA) for the Orbiting Carbon Observatory-2 Project. Work at Colorado State University and the Geology and Planetary Sciences Department at the California Institute of Technology was supported by subcontracts from the OCO-2 Project. \n\nEdited by: H. Worden \nReviewed by: two anonymous referees\n\nPublished - amt-10-549-2017.pdf
", "abstract": "The Orbiting Carbon Observatory-2 (OCO-2) is the first National Aeronautics and Space Administration (NASA) satellite designed to measure atmospheric carbon dioxide (CO_2) with the accuracy, resolution, and coverage needed to quantify CO_2 fluxes (sources and sinks) on regional scales. OCO-2 was successfully launched on 2 July 2014 and has gathered more than 2 years of observations. The v7/v7r operational data products from September 2014 to January 2016 are discussed here. On monthly timescales, 7 to 12\u202f% of these measurements are sufficiently cloud and aerosol free to yield estimates of the column-averaged atmospheric CO_2 dry air mole fraction, X_(CO)_2, that pass all quality tests. During the first year of operations, the observing strategy, instrument calibration, and retrieval algorithm were optimized to improve both the data yield and the accuracy of the products. With these changes, global maps of X_(CO)_2 derived from the OCO-2 data are revealing some of the most robust features of the atmospheric carbon cycle. This includes X_(CO)_2 enhancements co-located with intense fossil fuel emissions in eastern US and eastern China, which are most obvious between October and December, when the north\u2013south X_(CO)_2 gradient is small. Enhanced X_(CO)_2 coincident with biomass burning in the Amazon, central Africa, and Indonesia is also evident in this season. In May and June, when the north\u2013south X_(CO)_2 gradient is largest, these sources are less apparent in global maps. During this part of the year, OCO-2 maps show a more than 10\u202fppm reduction in X_(CO)_2 across the Northern Hemisphere, as photosynthesis by the land biosphere rapidly absorbs CO_2. As the carbon cycle science community continues to analyze these OCO-2 data, information on regional-scale sources (emitters) and sinks (absorbers) which impart X_(CO)_2 changes on the order of 1\u202fppm, as well as far more subtle features, will emerge from this high-resolution global dataset.", "date": "2017-02", "date_type": "published", "publication": "Atmospheric Measurement Techniques", "volume": "10", "number": "2", "publisher": "European Geosciences Union", "pagerange": "549-563", "id_number": "CaltechAUTHORS:20180306-103448109", "issn": "1867-8548", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180306-103448109", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA/JPL/Caltech" }, { "agency": "Orbiting Carbon Observatory 2 (OCO-2)" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/amt-10-549-2017", "primary_object": { "basename": "amt-10-549-2017.pdf", "url": "https://authors.library.caltech.edu/records/e1afe-mc689/files/amt-10-549-2017.pdf" }, "resource_type": "article", "pub_year": "2017", "author_list": "Eldering, Annmarie; Wennberg, Paul O.; et el." }, { "id": "https://authors.library.caltech.edu/records/eg392-hnb54", "eprint_id": 84784, "eprint_status": "archive", "datestamp": "2023-08-22 19:30:07", "lastmod": "2023-10-18 16:41:27", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Crisp-D", "name": { "family": "Crisp", "given": "David" }, "orcid": "0000-0002-4573-9998" }, { "id": "Pollock-H-R", "name": { "family": "Pollock", "given": "Harold R." } }, { "id": "Rosenberg-R", "name": { "family": "Rosenberg", "given": "Robert" }, "orcid": "0000-0002-0459-4630" }, { "id": "Chapsky-L", "name": { "family": "Chapsky", "given": "Lars" } }, { "id": "Lee-R-A-M", "name": { "family": "Lee", "given": "Richard A. M." }, "orcid": "0000-0001-6509-697X" }, { "id": "Oyafuso-F-A", "name": { "family": "Oyafuso", "given": "Fabiano A." }, "orcid": "0000-0002-8862-8737" }, { "id": "Frankenberg-C", "name": { "family": "Frankenberg", "given": "Christian" }, "orcid": "0000-0002-0546-5857" }, { "id": "O'Dell-C-W", "name": { "family": "O'Dell", "given": "Christopher W." } }, { "id": "Bruegge-C-J", "name": { "family": "Bruegge", "given": "Carol J." } }, { "id": "Doran-G-B", "name": { "family": "Doran", "given": "Gary B." } }, { "id": "Eldering-A", "name": { "family": "Eldering", "given": "Annmarie" }, "orcid": "0000-0003-1080-9922" }, { "id": "Fisher-B-M", "name": { "family": "Fisher", "given": "Brendan M." } }, { "id": "Fu-Dejian", "name": { "family": "Fu", "given": "Dejian" } }, { "id": "Gunson-M-R", "name": { "family": "Gunson", "given": "Michael R." } }, { "id": "Mandrake-L", "name": { "family": "Mandrake", "given": "Lukas" } }, { "id": "Osterman-G-B", "name": { "family": "Osterman", "given": "Gregory B." } }, { "id": "Schwandner-F-M", "name": { "family": "Schwandner", "given": "Florian M." } }, { "id": "Sun-Kang", "name": { "family": "Sun", "given": "Kang" } }, { "id": "Taylor-T-E", "name": { "family": "Taylor", "given": "Tommy E." } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Wunch-D", "name": { "family": "Wunch", "given": "Debra" }, "orcid": "0000-0002-4924-0377" } ] }, "title": "The on-orbit performance of the Orbiting Carbon Observatory-2 (OCO-2) instrument and its radiometrically calibrated products", "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: 28 Aug 2016. Discussion started: 04 Oct 2016. Revised: 01 Dec 2016. Accepted: 01 Dec 2016. Published: 05 Jan 2017. \n\nPart of the research described in this paper was carried out at the Jet Propulsion Laboratory, California Institute\nof Technology, under a contract with the National Aeronautics and Space Administration. The CSU/CIRA contribution to this work was supported by JPL subcontract 1439002. \n\nGovernment sponsorship is acknowledged. \n\nEdited by: A. Kokhanovsky \n\nReviewed by: four anonymous referees\n\nPublished - amt-10-59-2017.pdf
", "abstract": "The Orbiting Carbon Observatory-2 (OCO-2) carries and points a three-channel imaging grating spectrometer designed to collect high-resolution, co-boresighted spectra of reflected sunlight within the molecular oxygen (O_2) A-band at 0.765 microns and the carbon dioxide (CO_2) bands at 1.61 and 2.06 microns. These measurements are calibrated and then combined into soundings that are analyzed to retrieve spatially resolved estimates of the column-averaged CO_2 dry-air mole fraction, XCO_2. Variations of XCO_2 in space and time are then analyzed in the context of the atmospheric transport to quantify surface sources and sinks of CO_2. This is a particularly challenging remote-sensing observation because all but the largest emission sources and natural absorbers produce only small (<\u202f0.25\u202f%) changes in the background XCO_2 field. High measurement precision is therefore essential to resolve these small variations, and high accuracy is needed because small biases in the retrieved XCO_2 distribution could be misinterpreted as evidence for CO_2 fluxes. \n\nTo meet its demanding measurement requirements, each OCO-2 spectrometer channel collects 24\u202fspectra\u202fs^(\u22121) across a narrow (<\u202f10\u202fkm) swath as the observatory flies over the sunlit hemisphere, yielding almost 1 million soundings each day. On monthly timescales, between 7 and 12\u202f% of these soundings pass the cloud screens and other data quality filters to yield full-column estimates of XCO_2. Each of these soundings has an unprecedented combination of spatial resolution (<\u202f3\u202fkm^2/sounding), spectral resolving power (\u03bb\u2215\u0394\u03bb\u202f>\u202f17\u202f000), dynamic range (\u223c\u202f10^4), and sensitivity (continuum signal-to-noise ratio\u202f>\u202f400). \n\nThe OCO-2 instrument performance was extensively characterized and calibrated prior to launch. In general, the instrument has performed as expected during its first 18 months in orbit. However, ongoing calibration and science analysis activities have revealed a number of subtle radiometric and spectroscopic challenges that affect the yield and quality of the OCO-2 data products. These issues include increased numbers of bad pixels, transient artifacts introduced by cosmic rays, radiance discontinuities for spatially non-uniform scenes, a misunderstanding of the instrument polarization orientation, and time-dependent changes in the throughput of the oxygen A-band channel. Here, we describe the OCO-2 instrument, its data products, and its on-orbit performance. We then summarize calibration challenges encountered during its first 18 months in orbit and the methods used to mitigate their impact on the calibrated radiance spectra distributed to the science community.", "date": "2017-01-05", "date_type": "published", "publication": "Atmospheric Measurement Techniques", "volume": "10", "number": "1", "publisher": "European Geosciences Union", "pagerange": "59-81", "id_number": "CaltechAUTHORS:20180212-091712957", "issn": "1867-8548", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180212-091712957", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA/JPL/Caltech" }, { "agency": "JPL", "grant_number": "1439002" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/amt-10-59-2017", "primary_object": { "basename": "amt-10-59-2017.pdf", "url": "https://authors.library.caltech.edu/records/eg392-hnb54/files/amt-10-59-2017.pdf" }, "resource_type": "article", "pub_year": "2017", "author_list": "Crisp, David; Pollock, Harold R.; et el." }, { "id": "https://authors.library.caltech.edu/records/z9101-may74", "eprint_id": 74284, "eprint_status": "archive", "datestamp": "2023-08-22 19:13:24", "lastmod": "2023-10-24 22:16:59", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Feiner-P-A", "name": { "family": "Feiner", "given": "Philip A." } }, { "id": "Brune-W-H", "name": { "family": "Brune", "given": "William H." }, "orcid": "0000-0002-1609-4051" }, { "id": "Miller-D-O", "name": { "family": "Miller", "given": "David O." } }, { "id": "Zhang-Li", "name": { "family": "Zhang", "given": "Li" } }, { "id": "Cohen-R-C", "name": { "family": "Cohen", "given": "Ronald C." }, "orcid": "0000-0001-6617-7691" }, { "id": "Romer-P-S", "name": { "family": "Romer", "given": "Paul S." }, "orcid": "0000-0002-4983-743X" }, { "id": "Goldstein-A-H", "name": { "family": "Goldstein", "given": "Allen H." }, "orcid": "0000-0003-4014-4896" }, { "id": "Keutsch-F-N", "name": { "family": "Keutsch", "given": "Frank N." } }, { "id": "Skog-K-M", "name": { "family": "Skog", "given": "Kate M." } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Nguyen-Tran-B", "name": { "family": "Nguyen", "given": "Tran B." } }, { "id": "Teng-Alex-P", "name": { "family": "Teng", "given": "Alex P." } }, { "id": "DeGouw-J", "name": { "family": "DeGouw", "given": "Joost" } }, { "id": "Koss-A", "name": { "family": "Koss", "given": "Abigail" } }, { "id": "Wild-R-J", "name": { "family": "Wild", "given": "Robert J." } }, { "id": "Brown-S-S", "name": { "family": "Brown", "given": "Steven S." } }, { "id": "Guenther-A-B", "name": { "family": "Guenther", "given": "Alex" }, "orcid": "0000-0001-6283-8288" }, { "id": "Edgerton-E-S", "name": { "family": "Edgerton", "given": "Eric" } }, { "id": "Baumann-K", "name": { "family": "Baumann", "given": "Karsten" } }, { "id": "Fry-J-L", "name": { "family": "Fry", "given": "Juliane L." } } ] }, "title": "Testing Atmospheric Oxidation in an Alabama Forest", "ispublished": "pub", "full_text_status": "public", "keywords": "Biosphere-atmosphere interaction; Chemistry, atmospheric", "note": "\u00a9 2017 American Meteorological Society. Open Choice. \n\n(Manuscript received 9 February 2016, in final form 16 August 2016) \n\nWe thank the SOAS campaign organizers and leadership (A. M. Carlton, A. Goldstein, J. Jimenez, R. W. Pinder, J. de Gouw, B. J. Turpin, and A. B. Guenther), NCAR EOL personnel, and our hosts in Brent, Alabama, especially Mayor Dennis Stripling, for a successful field campaign. We also thank B. Baier for performing some model simulations and S. Kim and H. Harder for helpful conversations. SOAS financing and support was given by NSF, the NCAR Earth Observing Laboratory, and the Electric Power Research Institute. The Penn State effort was supported by NSF Grant AGS-1246918. Caltech acknowledges funding from the National Science Foundation (NSF) under Grant AGS-1240604 and NSF Postdoctoral Research Fellowship Program Award AGS-1331360. The University of Wisconsin\u2013Madison and Harvard acknowledge funding from the National Science Foundation (NSF) under Grants AGS-1247421 and AGS-1628530.\n\nPublished - jas-d-16-0044.1.pdf
Supplemental Material - 10.1175_jas-d-16-0044.s1.docx
", "abstract": "The chemical species emitted by forests create complex atmospheric oxidation chemistry and influence global atmospheric oxidation capacity and climate. The Southern Oxidant and Aerosol Study (SOAS) provided an opportunity to test the oxidation chemistry in a forest where isoprene is the dominant biogenic volatile organic compound. Hydroxyl (OH) and hydroperoxyl (HO_2) radicals were two of the hundreds of atmospheric chemical species measured, as was OH reactivity (the inverse of the OH lifetime). OH was measured by laser-induced fluorescence (LIF) and by taking the difference in signals without and with an OH scavenger that was added just outside the instrument's pinhole inlet. To test whether the chemistry at SOAS can be simulated by current model mechanisms, OH and HO_2 were evaluated with a box model using two chemical mechanisms: Master Chemical Mechanism, version 3.2 (MCMv3.2), augmented with explicit isoprene chemistry and MCMv3.3.1. Measured and modeled OH peak at about 10^6 cm^(\u22123) and agree well within combined uncertainties. Measured and modeled HO_2 peak at about 27 pptv and also agree well within combined uncertainties. Median OH reactivity cycled between about 11 s^(\u22121) at dawn and about 26 s^(\u22121) during midafternoon. A good test of the oxidation chemistry is the balance between OH production and loss rates using measurements; this balance was observed to within uncertainties. These SOAS results provide strong evidence that the current isoprene mechanisms are consistent with measured OH and HO_2 and, thus, capture significant aspects of the atmospheric oxidation chemistry in this isoprene-rich forest.", "date": "2016-12", "date_type": "published", "publication": "Journal of the Atmospheric Sciences", "volume": "73", "number": "12", "publisher": "American Meteorological Society", "pagerange": "4699-4710", "id_number": "CaltechAUTHORS:20170213-165652994", "issn": "0022-4928", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170213-165652994", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "AGS-1246918" }, { "agency": "National Center for Atmospheric Research (NCAR)" }, { "agency": "Electric Power Research Institute (EPRI)" }, { "agency": "NSF", "grant_number": "AGS-1240604" }, { "agency": "NSF Postdoctoral Research Fellowship", "grant_number": "AGS-1331360" }, { "agency": "NSF", "grant_number": "AGS-1247421" }, { "agency": "NSF", "grant_number": "AGS-1628530" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1175/JAS-D-16-0044.1", "primary_object": { "basename": "10.1175_jas-d-16-0044.s1.docx", "url": "https://authors.library.caltech.edu/records/z9101-may74/files/10.1175_jas-d-16-0044.s1.docx" }, "related_objects": [ { "basename": "jas-d-16-0044.1.pdf", "url": "https://authors.library.caltech.edu/records/z9101-may74/files/jas-d-16-0044.1.pdf" } ], "resource_type": "article", "pub_year": "2016", "author_list": "Feiner, Philip A.; Brune, William H.; et el." }, { "id": "https://authors.library.caltech.edu/records/cg56w-ghv16", "eprint_id": 73255, "eprint_status": "archive", "datestamp": "2023-08-22 19:07:46", "lastmod": "2023-10-24 15:09:59", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Frandsen-B-N", "name": { "family": "Frandsen", "given": "Benjamin N." } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Kjaergaard-H-G", "name": { "family": "Kjaergaard", "given": "Henrik G." }, "orcid": "0000-0002-7275-8297" } ] }, "title": "Identification of OSSO as a near-UV absorber in the Venusian atmosphere", "ispublished": "pub", "full_text_status": "public", "keywords": "Venus Atmosphere; Sulfur oxides; Near-UV absorption", "note": "\u00a9 2016 American Geophysical Union. \n\nReceived 30 MAR 2016; Accepted 21 SEP 2016; Published online 3 NOV 2016. \n\nWe thank Yuk L. Yung for his assistance in interpreting the contribution of OSSO to the observed near-UV opacity at Venus. We thank Veronica Vaida, Theo Kurten, Stephan P. A. Sauer, and Matthew S. Johnson for helpful discussions and Tyler Robinson for providing the digitalized files of the unknown absorber from Haus et al. [2015, Figure 18]. We acknowledge the financial support from the Danish Center for Scientific Computing, University of Copenhagen and the Center for Exploitation of Solar Energy founded by the University of Copenhagen. The data used are listed in the supporting information.\n\nPublished - Frandsen_et_al-2016-Geophysical_Research_Letters.pdf
Supplemental Material - grl55057-sup-0001-supplementary.pdf
Supplemental Material - grl55057-sup-0002-TableS1.csv
Supplemental Material - grl55057-sup-0003-TableS2.csv
", "abstract": "The planet Venus exhibits atmospheric absorption in the 320\u2013400 nm wavelength range produced by unknown chemistry. We investigate electronic transitions in molecules that may exist in the atmosphere of Venus. We identify two different S_2O_2 isomers, cis-OSSO and trans-OSSO, which are formed in significant amounts and are removed predominantly by near-UV photolysis. We estimate the rate of photolysis of cis- and trans-OSSO in the Venusian atmosphere and find that they are good candidates to explain the enigmatic 320\u2013400 nm near-UV absorption. Between 58 and 70 km, the calculated OSSO concentrations are similar to those of sulfur monoxide (SO), generally thought to be the second most abundant sulfur oxide on Venus.", "date": "2016-11-16", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "43", "number": "21", "publisher": "American Geophysical Union", "pagerange": "11146-11155", "id_number": "CaltechAUTHORS:20170105-084008003", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170105-084008003", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Danish Center for Scientific Computing" }, { "agency": "University of Copenhagen" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1002/2016GL070916", "primary_object": { "basename": "Frandsen_et_al-2016-Geophysical_Research_Letters.pdf", "url": "https://authors.library.caltech.edu/records/cg56w-ghv16/files/Frandsen_et_al-2016-Geophysical_Research_Letters.pdf" }, "related_objects": [ { "basename": "grl55057-sup-0001-supplementary.pdf", "url": "https://authors.library.caltech.edu/records/cg56w-ghv16/files/grl55057-sup-0001-supplementary.pdf" }, { "basename": "grl55057-sup-0002-TableS1.csv", "url": "https://authors.library.caltech.edu/records/cg56w-ghv16/files/grl55057-sup-0002-TableS1.csv" }, { "basename": "grl55057-sup-0003-TableS2.csv", "url": "https://authors.library.caltech.edu/records/cg56w-ghv16/files/grl55057-sup-0003-TableS2.csv" } ], "resource_type": "article", "pub_year": "2016", "author_list": "Frandsen, Benjamin N.; Wennberg, Paul O.; et el." }, { "id": "https://authors.library.caltech.edu/records/kjvxd-0v185", "eprint_id": 103564, "eprint_status": "archive", "datestamp": "2023-08-22 19:07:18", "lastmod": "2023-10-20 16:29:55", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Wunch-D", "name": { "family": "Wunch", "given": "Debra" }, "orcid": "0000-0002-4924-0377" }, { "id": "Toon-G-C", "name": { "family": "Toon", "given": "Geoffrey C." }, "orcid": "0000-0003-4174-7541" }, { "id": "Hedelius-J-K", "name": { "family": "Hedelius", "given": "Jacob K." }, "orcid": "0000-0003-2025-7519" }, { "id": "Vizenor-N", "name": { "family": "Vizenor", "given": "Nicholas" } }, { "id": "Roehl-C-M", "name": { "family": "Roehl", "given": "Coleen M." }, "orcid": "0000-0001-5383-8462" }, { "id": "Saad-K-M", "name": { "family": "Saad", "given": "Katherine M." }, "orcid": "0000-0002-2501-6223" }, { "id": "Blavier-J-F-L", "name": { "family": "Blavier", "given": "Jean-Fran\u00e7ois L." } }, { "id": "Blake-D-R", "name": { "family": "Blake", "given": "Donald R." } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "Quantifying the loss of processed natural gas within California's South Coast Air Basin using long-term measurements of ethane and methane", "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: 26 Apr 2016 \u2013 Discussion started: 17 May 2016 \u2013 Revised: 13 Sep 2016 \u2013 Accepted: 18 Oct 2016 \u2013 Published: 15 Nov 2016. \n\nPart of this work was performed at the Jet Propulsion Laboratory, California Institute of Technology, under contract with NASA. We thank the various people who have assisted with MkIV ground-based observations over the years, as well as the NASA Upper Atmosphere Research Program for funding. This research was supported by NASA's Carbon Cycle Science program (NNX14AI60G). TCCON data were obtained from the TCCON Data Archive, hosted by the Carbon Dioxide Information Analysis Center (CDIAC) \u2013 http://tccon.ornl.gov. We thank four anonymous reviewers and D. Lyon for providing thoughtful reviews that significantly improved this paper. \n\nData availability. TCCON data are available from the TCCON data archive, hosted by CDIAC: http://tccon.ornl.gov. Each TCCON dataset used in this paper is cited independently. The JPL MkIV FTS data are available from the webpage http://mark4sun.jpl.nasa.gov/ground.html. \n\nEdited by: R. Volkamer. Reviewed by: four anonymous referees.\n\nPublished - acp-16-14091-2016.pdf
", "abstract": "Methane emissions inventories for Southern California's South Coast Air Basin (SoCAB) have underestimated emissions from atmospheric measurements. To provide insight into the sources of the discrepancy, we analyze records of atmospheric trace gas total column abundances in the SoCAB starting in the late 1980s to produce annual estimates of the ethane emissions from 1989 to 2015 and methane emissions from 2007 to 2015. The first decade of measurements shows a rapid decline in ethane emissions coincident with decreasing natural gas and crude oil production in the basin. Between 2010 and 2015, however, ethane emissions have grown gradually from about 13\u202f\u00b1\u202f5 to about 23\u202f\u00b1\u202f3\u202fGg\u202fyr\u207b\u00b9, despite the steady production of natural gas and oil over that time period. The methane emissions record begins with 1 year of measurements in 2007 and continuous measurements from 2011 to 2016 and shows little trend over time, with an average emission rate of 413\u202f\u00b1\u202f86\u202fGg\u202fyr\u207b\u00b9. Since 2012, ethane to methane ratios in the natural gas withdrawn from a storage facility within the SoCAB have been increasing by 0.62\u202f\u00b1\u202f0.05\u202f%\u202fyr\u207b\u00b9, consistent with the ratios measured in the delivered gas. Our atmospheric measurements also show an increase in these ratios but with a slope of 0.36\u202f\u00b1\u202f0.08\u202f%\u202fyr\u207b\u00b9, or 58\u202f\u00b1\u202f13\u202f% of the slope calculated from the withdrawn gas. From this, we infer that more than half of the excess methane in the SoCAB between 2012 and 2015 is attributable to losses from the natural gas infrastructure.", "date": "2016-11-15", "date_type": "published", "publication": "Atmospheric Chemistry and Physics", "volume": "16", "number": "22", "publisher": "European Geosciences Union", "pagerange": "14091-14105", "id_number": "CaltechAUTHORS:20200529-093434423", "issn": "1680-7324", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200529-093434423", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA/JPL/Caltech" }, { "agency": "NASA", "grant_number": "NNX14AI60G" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/acp-16-14091-2016", "primary_object": { "basename": "acp-16-14091-2016.pdf", "url": "https://authors.library.caltech.edu/records/kjvxd-0v185/files/acp-16-14091-2016.pdf" }, "resource_type": "article", "pub_year": "2016", "author_list": "Wunch, Debra; Toon, Geoffrey C.; et el." }, { "id": "https://authors.library.caltech.edu/records/0tb2d-jxt44", "eprint_id": 72599, "eprint_status": "archive", "datestamp": "2023-08-22 19:05:42", "lastmod": "2023-10-23 22:45:40", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Saad-K-M", "name": { "family": "Saad", "given": "Katherine M." } }, { "id": "Wunch-D", "name": { "family": "Wunch", "given": "Debra" }, "orcid": "0000-0002-4924-0377" }, { "id": "Deutscher-N-M", "name": { "family": "Deutscher", "given": "Nicholas M." }, "orcid": "0000-0002-2906-2577" }, { "id": "Griffith-D-W-T", "name": { "family": "Griffith", "given": "David W. T." }, "orcid": "0000-0002-7986-1924" }, { "id": "Hase-F", "name": { "family": "Hase", "given": "Frank" } }, { "id": "De-Mazi\u00e8re-M", "name": { "family": "De Mazi\u00e8re", "given": "Martine" } }, { "id": "Notholt-J", "name": { "family": "Notholt", "given": "Justus" } }, { "id": "Pollard-D-F", "name": { "family": "Pollard", "given": "David F." }, "orcid": "0000-0001-9923-2984" }, { "id": "Roehl-C-M", "name": { "family": "Roehl", "given": "Coleen M." }, "orcid": "0000-0001-5383-8462" }, { "id": "Schneider-M", "name": { "family": "Schneider", "given": "Matthias" } }, { "id": "Sussmann-R", "name": { "family": "Sussmann", "given": "Ralf" } }, { "id": "Warneke-T", "name": { "family": "Warneke", "given": "Thorsten" }, "orcid": "0000-0001-5185-3415" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "Seasonal variability of stratospheric methane: implications for constraining tropospheric methane budgets using total column observations", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2016 Author(s) 2016. This work is distributed under the Creative Commons Attribution 3.0 License. \n\nReceived: 07 Apr 2016 \u2013 Published in Atmos. Chem. Phys. Discuss.: 10 May 2016. Revised: 24 Oct 2016 \u2013 Accepted: 25 Oct 2016 \u2013 Published: 11 Nov 2016. \n\nThis work was supported by NASA Headquarters under the NASA Earth and Space Science Fellowship Program grant NNX14AL30H and NASA's Carbon Cycle Science program. Park Falls, Lamont, and JPL are funded by NASA grants NNX14AI60G, NNX11AG01G, NAG5-12247, NNG05-GD07G, and NASA Orbiting Carbon Observatory Program; we are grateful to the DOE ARM program and Jeff Ayers for their technical support in Lamont and Park Falls, respectively. Darwin and Wollongong are funded by NASA grants NAG5-12247 and NNG05-GD07G and the Australian Research Council grants DP140101552, DP110103118, DP0879468, and LP0562346, and Nicholas Deutscher is supported by an Australian Research Council Fellowship, DE140100178; we are grateful to the DOE ARM program for technical support in Darwin. Bremen, Bialystok, and Orleans are funded by the EU projects InGOS and ICOS-INWIRE and by the Senate of Bremen. R\u00e9union Island is funded by the EU FP7 project ICOS-INWIRE, the national Belgian support to ICOS and the AGACC-II project (Science for Sustainable Development Program), the Universit\u00e9 de la R\u00e9union, and the French regional and national organizations (INSU, CNRS). From 2004 to 2011 the Lauder TCCON program was funded by the New Zealand Foundation of Research Science and Technology contracts CO1X0204, CO1X0703, and CO1X0406. We thank Shuji Kawakami for his technical support in Saga. We thank Peter Bernath, Kaley Walker, and Chris Boone for their guidance using the ACE-FTS data, which were obtained through the Atmospheric Chemistry Experiment (ACE) mission, primarily funded by the Canadian Space Agency. We are grateful to Geoff Toon for his continuous efforts developing the GGG software, for providing the MkIV data, and his input on the manuscript. We thank Arlyn Andrews for providing the LEF surface flask data, which were generated by NOAA-ESRL, Carbon Cycle Greenhouse Gases Group. Baring Head NIWA surface data were provided courtesy of Gordon Brailsford, Dave Lowe, and Ross Martin. We also acknowledge the contributions of in situ vertical profiles from the AirCore, HIPPO, IMECC, INTEX, Learjet, and START08 campaigns. We are grateful to Kelvin Bates for providing monthly OH fields for the GEOS-Chem Updated OH sensitivity experiments. Lastly, we thank the three anonymous reviewers who provided feedback and suggestions.\n\nPublished - acp-16-14003-2016.pdf
", "abstract": "Global and regional methane budgets are markedly uncertain. Conventionally, estimates of methane sources are derived by bridging emissions inventories with atmospheric observations employing chemical transport models. The accuracy of this approach requires correctly simulating advection and chemical loss such that modeled methane concentrations scale with surface fluxes. When total column measurements are assimilated into this framework, modeled stratospheric methane introduces additional potential for error. To evaluate the impact of such errors, we compare Total Carbon Column Observing Network (TCCON) and GEOS-Chem total and tropospheric column-averaged dry-air mole fractions of methane. We find that the model's stratospheric contribution to the total column is insensitive to perturbations to the seasonality or distribution of tropospheric emissions or loss. In the Northern Hemisphere, we identify disagreement between the measured and modeled stratospheric contribution, which increases as the tropopause altitude decreases, and a temporal phase lag in the model's tropospheric seasonality driven by transport errors. Within the context of GEOS-Chem, we find that the errors in tropospheric advection partially compensate for the stratospheric methane errors, masking inconsistencies between the modeled and measured tropospheric methane. These seasonally varying errors alias into source attributions resulting from model inversions. In particular, we suggest that the tropospheric phase lag error leads to large misdiagnoses of wetland emissions in the high latitudes of the Northern Hemisphere.", "date": "2016-11-11", "date_type": "published", "publication": "Atmospheric Chemistry and Physics", "volume": "16", "number": "21", "publisher": "European Geosciences Union", "pagerange": "14003-14024", "id_number": "CaltechAUTHORS:20161206-132313816", "issn": "1680-7324", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20161206-132313816", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NNX14AL30H" }, { "agency": "NASA", "grant_number": "NNX14AI60G" }, { "agency": "NASA", "grant_number": "NNX11AG01G" }, { "agency": "NASA", "grant_number": "NAG5-12247" }, { "agency": "NASA", "grant_number": "NNG05-GD07G" }, { "agency": "Australian Research Council", "grant_number": "DP140101552" }, { "agency": "Australian Research Council", "grant_number": "DP110103118" }, { "agency": "Australian Research Council", "grant_number": "DP0879468" }, { "agency": "Australian Research Council", "grant_number": "LP0562346" }, { "agency": "Australian Research Council", "grant_number": "DE140100178" }, { "agency": "European Union", "grant_number": "InGOS" }, { "agency": "European Union", "grant_number": "ICOS-INWIRE" }, { "agency": "Senate of Bremen" }, { "agency": "Universit\u00e9 de la R\u00e9union" }, { "agency": "Institut national des sciences de l'Univers (INSU)" }, { "agency": "Centre National de la Recherche Scientifique (CNRS)" }, { "agency": "New Zealand Foundation of Research Science and Technology", "grant_number": "CO1X0204" }, { "agency": "New Zealand Foundation of Research Science and Technology", "grant_number": "CO1X0703" }, { "agency": "New Zealand Foundation of Research Science and Technology", "grant_number": "CO1X0406" }, { "agency": "Canadian Space Agency (CSA)" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/acp-16-14003-2016", "primary_object": { "basename": "acp-16-14003-2016.pdf", "url": "https://authors.library.caltech.edu/records/0tb2d-jxt44/files/acp-16-14003-2016.pdf" }, "resource_type": "article", "pub_year": "2016", "author_list": "Saad, Katherine M.; Wunch, Debra; et el." }, { "id": "https://authors.library.caltech.edu/records/fh6fb-2zn78", "eprint_id": 72589, "eprint_status": "archive", "datestamp": "2023-08-22 19:03:31", "lastmod": "2023-10-23 22:45:06", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Travis-K-R", "name": { "family": "Travis", "given": "Katherine R." }, "orcid": "0000-0003-1628-0353" }, { "id": "Jacob-D-J", "name": { "family": "Jacob", "given": "Daniel J." }, "orcid": "0000-0002-6373-3100" }, { "id": "Fisher-J-A", "name": { "family": "Fisher", "given": "Jenny A." } }, { "id": "Kim-Patrick-S", "name": { "family": "Kim", "given": "Patrick S." } }, { "id": "Marais-E-A", "name": { "family": "Marais", "given": "Eloise A." }, "orcid": "0000-0001-5477-8051" }, { "id": "Zhu-Lei", "name": { "family": "Zhu", "given": "Lei" } }, { "id": "Yu-Karen", "name": { "family": "Yu", "given": "Karen" } }, { "id": "Miller-C-C", "name": { "family": "Miller", "given": "Christopher C." } }, { "id": "Yantosca-R-M", "name": { "family": "Yantosca", "given": "Robert M." } }, { "id": "Sulprizio-M-P", "name": { "family": "Sulprizio", "given": "Melissa P." }, "orcid": "0000-0003-4641-5546" }, { "id": "Thompson-A-M", "name": { "family": "Thompson", "given": "Anne M." } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Crounse-J-D", "name": { "family": "Crounse", "given": "John D." }, "orcid": "0000-0001-5443-729X" }, { "id": "St-Clair-J-M", "name": { "family": "St. Clair", "given": "Jason M." }, "orcid": "0000-0002-9367-5749" }, { "id": "Cohen-R-C", "name": { "family": "Cohen", "given": "Ronald C." }, "orcid": "0000-0001-6617-7691" }, { "id": "Laughner-J-L", "name": { "family": "Laughner", "given": "Joshua L." }, "orcid": "0000-0002-8599-4555" }, { "id": "Dibb-J-E", "name": { "family": "Dibb", "given": "Jack E." }, "orcid": "0000-0003-3096-7709" }, { "id": "Hall-S-R", "name": { "family": "Hall", "given": "Samuel R." }, "orcid": "0000-0002-2060-7112" }, { "id": "Ullmann-K", "name": { "family": "Ullmann", "given": "Kirk" }, "orcid": "0000-0002-4724-9634" }, { "id": "Wolfe-G-M", "name": { "family": "Wolfe", "given": "Glenn M." }, "orcid": "0000-0001-6586-4043" }, { "id": "Pollack-I-B", "name": { "family": "Pollack", "given": "Illana B." }, "orcid": "0000-0001-7151-9756" }, { "id": "Peischl-J", "name": { "family": "Peischl", "given": "Jeff" }, "orcid": "0000-0002-9320-7101" }, { "id": "Neuman-J-A", "name": { "family": "Neuman", "given": "Jonathan A." } }, { "id": "Zhou-Xianliang", "name": { "family": "Zhou", "given": "Xianliang" } } ] }, "title": "Why do models overestimate surface ozone in the Southeast United States?", "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: 03 Feb 2016 \u2013 Published in Atmos. Chem. Phys. Discuss.: 16 Mar 2016; Revised: 05 Oct 2016 \u2013 Accepted: 06 Oct 2016 \u2013 Published: 01 Nov 2016. \n\nWe are grateful to the entire NASA SEAC4RS team for their help in the field. We thank Tom Ryerson for his measurements of NO and NO_2 from the NOAA NO_yO_3 instrument. We thank L. Gregory Huey for the use of his CIMS PAN measurements. We thank Fabien Paulot and Jingqiu Mao for their helpful discussions of isoprene chemistry. We thank Christoph Keller for his help in implementing the NEI11v1 emissions into GEOS-Chem. We acknowledge the EPA for providing the 2011 North American emission inventory and in particular George Pouliot for his help and advice. These emission inventories are intended for research purposes. A technical report describing the 2011 modeling platform can be found at https://www.epa.gov/sites/production/files/2015-10/documents/nei2011v2_tsd_14aug2015.pdf. A description of the 2011 NEI can be found at https://www.epa.gov/air-emissions-inventories/national-emissions-inventory. This work was supported by the NASA Earth Science Division and by STAR Fellowship Assistance Agreement no. 91761601-0 awarded by the US Environmental Protection Agency (EPA). It has not been formally reviewed by EPA. The views expressed in this publication are solely those of the authors. JAF acknowledges support from a University of Wollongong Vice Chancellor's Postdoctoral Fellowship. This research was undertaken with the assistance of resources provided\nat the NCI National Facility systems at the Australian National University through the National Computational Merit Allocation Scheme supported by the Australian Government.\n\nPublished - acp-16-13561-2016.pdf
Accepted Version - nihms952667.pdf
Supplemental Material - acp-16-13561-2016-supplement.pdf
", "abstract": "Ozone pollution in the Southeast US involves complex chemistry driven by emissions of anthropogenic nitrogen oxide radicals (NO_x\u202f\u2009\u2261\u2009\u202fNO\u202f+\u202fNO_2) and biogenic isoprene. Model estimates of surface ozone concentrations tend to be biased high in the region and this is of concern for designing effective emission control strategies to meet air quality standards. We use detailed chemical observations from the SEAC^4RS aircraft campaign in August and September 2013, interpreted with the GEOS-Chem chemical transport model at 0.25\u00b0\u202f\u2009\u00d7\u2009\u202f0.3125\u00b0 horizontal resolution, to better understand the factors controlling surface ozone in the Southeast US. We find that the National Emission Inventory (NEI) for NO_x from the US Environmental Protection Agency (EPA) is too high. This finding is based on SEAC^4RS observations of NO_x and its oxidation products, surface network observations of nitrate wet deposition fluxes, and OMI satellite observations of tropospheric NO_2 columns. Our results indicate that NEI NO_x emissions from mobile and industrial sources must be reduced by 30\u201360\u202f%, dependent on the assumption of the contribution by soil NO_x emissions. Upper-tropospheric NO_2 from lightning makes a large contribution to satellite observations of tropospheric NO_2 that must be accounted for when using these data to estimate surface NO_x emissions. We find that only half of isoprene oxidation proceeds by the high-NO_x pathway to produce ozone; this fraction is only moderately sensitive to changes in NO_x emissions because isoprene and NO_x emissions are spatially segregated. GEOS-Chem with reduced NO_x emissions provides an unbiased simulation of ozone observations from the aircraft and reproduces the observed ozone production efficiency in the boundary layer as derived from a regression of ozone and NO_x oxidation products. However, the model is still biased high by 6\u202f\u00b1\u202f14\u202fppb relative to observed surface ozone in the Southeast US. Ozonesondes launched during midday hours show a 7\u202fppb ozone decrease from 1.5\u202fkm to the surface that GEOS-Chem does not capture. This bias may reflect a combination of excessive vertical mixing and net ozone production in the model boundary layer.", "date": "2016-11-01", "date_type": "published", "publication": "Atmospheric Chemistry and Physics", "volume": "16", "number": "21", "publisher": "European Geosciences Union", "pagerange": "13561-13577", "id_number": "CaltechAUTHORS:20161206-085019989", "issn": "1680-7324", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20161206-085019989", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "91761601-0" }, { "agency": "Environmental Protection Agency (EPA)" }, { "agency": "University of Wollongong" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/acp-16-13561-2016", "pmcid": "PMC5880041", "primary_object": { "basename": "acp-16-13561-2016-supplement.pdf", "url": "https://authors.library.caltech.edu/records/fh6fb-2zn78/files/acp-16-13561-2016-supplement.pdf" }, "related_objects": [ { "basename": "acp-16-13561-2016.pdf", "url": "https://authors.library.caltech.edu/records/fh6fb-2zn78/files/acp-16-13561-2016.pdf" }, { "basename": "nihms952667.pdf", "url": "https://authors.library.caltech.edu/records/fh6fb-2zn78/files/nihms952667.pdf" } ], "resource_type": "article", "pub_year": "2016", "author_list": "Travis, Katherine R.; Jacob, Daniel J.; et el." }, { "id": "https://authors.library.caltech.edu/records/nw9sv-ey917", "eprint_id": 71311, "eprint_status": "archive", "datestamp": "2023-08-22 18:37:09", "lastmod": "2023-10-23 15:37:42", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "St-Clair-Jason-M", "name": { "family": "St. Clair", "given": "Jason M." }, "orcid": "0000-0002-9367-5749" }, { "id": "Rivera-Rios-Jean-C", "name": { "family": "Rivera-Rios", "given": "Jean C." }, "orcid": "0000-0003-2108-9131" }, { "id": "Crounse-John-D", "name": { "family": "Crounse", "given": "John D." }, "orcid": "0000-0001-5443-729X" }, { "id": "Praske-Eric", "name": { "family": "Praske", "given": "Eric" }, "orcid": "0000-0001-7169-4423" }, { "id": "Kim-Michelle-J", "name": { "family": "Kim", "given": "Michelle J." }, "orcid": "0000-0002-4922-4334" }, { "id": "Wolfe-Glenn-M", "name": { "family": "Wolfe", "given": "Glenn M." }, "orcid": "0000-0001-6586-4043" }, { "id": "Keutsch-Frank-N", "name": { "family": "Keutsch", "given": "Frank N." }, "orcid": "0000-0002-1442-6200" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Hanisco-Thomas-F", "name": { "family": "Hanisco", "given": "Thomas F." }, "orcid": "0000-0001-9434-8507" } ] }, "title": "Investigation of a potential HCHO measurement artifact from ISOPOOH", "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: 13 Jun 2016 \u2013 Published in Atmos. Meas. Tech. Discuss.: 16 Jun 2016; Revised: 12 Aug 2016 \u2013 Accepted: 15 Aug 2016 \u2013 Published: 16 Sep 2016. \n\nF. N. Keutsch and J. C. Rivera-Rios were supported by the National Science Foundation (AGS 1628491, 1628530, 1247421, 1321987). J. M. St. Clair, G. M. Wolfe, and T. F. Hanisco were supported by NASA (NNH12ZDA001N-UACO). M. J. Kim was supported by the National Science Foundation (AGS PRF 1524860).\n\nPublished - amt-9-4561-2016.pdf
Accepted Version - nihms952688.pdf
Supplemental Material - amt-9-4561-2016-supplement.pdf
", "abstract": "Recent laboratory experiments have shown that a first generation isoprene oxidation product, ISOPOOH, can decompose to methyl vinyl ketone (MVK) and methacrolein (MACR) on instrument surfaces, leading to overestimates of MVK and MACR concentrations. Formaldehyde (HCHO) was suggested as a decomposition co-product, raising concern that in situ HCHO measurements may also be affected by an ISOPOOH interference. The HCHO measurement artifact from ISOPOOH for the NASA In Situ Airborne Formaldehyde instrument (ISAF) was investigated for the two major ISOPOOH isomers, (1,2)-ISOPOOH and (4,3)-ISOPOOH, under dry and humid conditions. The dry conversion of ISOPOOH to HCHO was 3\u202f\u00b1\u202f2\u202f% and 6\u202f\u00b1\u202f4\u202f% for (1,2)-ISOPOOH and (4,3)-ISOPOOH, respectively. Under humid (relative humidity of 40\u201360\u202f%) conditions, conversion to HCHO was 6\u202f\u00b1\u202f4\u202f% for (1,2)-ISOPOOH and 10\u202f\u00b1\u202f5\u202f% for (4,3)-ISOPOOH. The measurement artifact caused by conversion of ISOPOOH to HCHO in the ISAF instrument was estimated for data obtained on the 6 September 2013 flight of the Studies of Emissions and Atmospheric Composition, Clouds and Climate Coupling by Regional Surveys (SEAC4RS) campaign. Prompt ISOPOOH conversion to HCHO was the source of <\u202f4\u202f% of the observed HCHO, including in the high-isoprene boundary layer. Time-delayed conversion, where previous exposure to ISOPOOH affects measured HCHO later in the flight, was conservatively estimated to be <\u202f10\u202f% of observed HCHO, and is significant only when high ISOPOOH sampling periods immediately precede periods of low HCHO.", "date": "2016-09", "date_type": "published", "publication": "Atmospheric Measurement Techniques", "volume": "9", "number": "9", "publisher": "European Geosciences Union", "pagerange": "4561-4568", "id_number": "CaltechAUTHORS:20161020-090716797", "issn": "1867-8548", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20161020-090716797", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "AGS-1628491" }, { "agency": "NSF", "grant_number": "AGS-1628530" }, { "agency": "NSF", "grant_number": "AGS-1247421" }, { "agency": "NSF", "grant_number": "AGS-1321987" }, { "agency": "NASA", "grant_number": "NNH12ZDA001N-UACO" }, { "agency": "NSF Atmospheric and Geospace Sciences Fellowship", "grant_number": "AGS-1524860" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/amt-9-4561-2016", "pmcid": "PMC5889939", "primary_object": { "basename": "nihms952688.pdf", "url": "https://authors.library.caltech.edu/records/nw9sv-ey917/files/nihms952688.pdf" }, "related_objects": [ { "basename": "amt-9-4561-2016-supplement.pdf", "url": "https://authors.library.caltech.edu/records/nw9sv-ey917/files/amt-9-4561-2016-supplement.pdf" }, { "basename": "amt-9-4561-2016.pdf", "url": "https://authors.library.caltech.edu/records/nw9sv-ey917/files/amt-9-4561-2016.pdf" } ], "resource_type": "article", "pub_year": "2016", "author_list": "St. Clair, Jason M.; Rivera-Rios, Jean C.; et el." }, { "id": "https://authors.library.caltech.edu/records/3prng-kzc28", "eprint_id": 82434, "eprint_status": "archive", "datestamp": "2023-08-20 13:17:22", "lastmod": "2023-10-17 22:16:55", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Hedelius-J-K", "name": { "family": "Hedelius", "given": "Jacob K." }, "orcid": "0000-0003-2025-7519" }, { "id": "Viatte-C", "name": { "family": "Viatte", "given": "Camille" } }, { "id": "Wunch-D", "name": { "family": "Wunch", "given": "Debra" }, "orcid": "0000-0002-4924-0377" }, { "id": "Roehl-C-M", "name": { "family": "Roehl", "given": "Coleen M." }, "orcid": "0000-0001-5383-8462" }, { "id": "Toon-G-C", "name": { "family": "Toon", "given": "Geoffrey C." }, "orcid": "0000-0003-4174-7541" }, { "id": "Chen-Jia", "name": { "family": "Chen", "given": "Jia" } }, { "id": "Jones-T", "name": { "family": "Jones", "given": "Taylor" }, "orcid": "0000-0001-5860-3419" }, { "id": "Wofsy-S-C", "name": { "family": "Wofsy", "given": "Steven C." }, "orcid": "0000-0002-3990-6737" }, { "id": "Franklin-J-E", "name": { "family": "Franklin", "given": "Jonathan E." } }, { "id": "Parker-H", "name": { "family": "Parker", "given": "Harrison" } }, { "id": "Dubey-M-K", "name": { "family": "Dubey", "given": "Manvendra K." } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "Assessment of errors and biases in retrievals of X_(CO2), X_(CH4), X_(CO), and X_(N2O) from a 0.5 cm^(-1) resolution solar-viewing spectrometer", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2016 Author(s). This work is distributed under the Creative Commons Attribution 3.0 License. \n\nPublished by Copernicus Publications on behalf of the European Geosciences Union. \n\nReceived: 05 Feb 2016 \u2013 Discussion started: 04 Mar 2016. Revised: 24 Jun 2016 \u2013 Accepted: 28 Jun 2016 \u2013 Published: 03 Aug 2016. \n\nWe thank Frank Hase and Michael Gisi for helpful discussions on ghost reduction, detector nonlinearity, and ILS measurements. We further thank Michael Gisi and Bruker Optics\u2122 for loaning us a standard InGaAs detector for testing and for instructions on realigning the EM27/SUN. We thank Dietrich Feist for discussions on mirror degradation. We also thank Nicholas Jones, David Giffith, Frank Hase, and Sabrina Arnold for sharing their experience with mirror degradation. This work is supported in part by the W. M. Keck Institute for Space Studies. Jacob Hedelius was also partially supported by a Caltech Chemistry and Chemical Engineering Division Fellowship funded by the Dow Chemical Graduate Fellowship, and expresses thanks to them. The authors gratefully acknowledge funding from the NASA Carbon Cycle Science program (grant number NNX14AI60G) and the Jet Propulsion Laboratory. Manvendra K. Dubey acknowledges funding from the NASA-CMS program for field observations and from the LANL-LDRD for the acquisition of the LANL EM27/SUN. Jia Chen, Taylor Jones, Jonathan E. Franklin, and Steven C. Wofsy acknowledge funding provided by NSF MRI Award 1337512. \n\nThe authors thank the referees for their comments. \n\nThe authors declare that they have no conflict of interest.\n\nPublished - amt-9-3527-2016.pdf
", "abstract": "Bruker\u2122 EM27/SUN instruments are commercial mobile solar-viewing near-IR spectrometers. They show promise for expanding the global density of atmospheric column measurements of greenhouse gases and are being marketed for such applications. They have been shown to measure the same variations of atmospheric gases within a day as the high-resolution spectrometers of the Total Carbon Column Observing Network (TCCON). However, there is little known about the long-term precision and uncertainty budgets of EM27/SUN measurements. In this study, which includes a comparison of 186 measurement days spanning 11 months, we note that atmospheric variations of X_(gas) within a single day are well captured by these low-resolution instruments, but over several months, the measurements drift noticeably. We present comparisons between EM27/SUN instruments and the TCCON using GGG as the retrieval algorithm. In addition, we perform several tests to evaluate the robustness of the performance and determine the largest sources of errors from these spectrometers. We include comparisons of X_(CO2), X_(CH4), X_(CO), and X_(N2)O. Specifically we note EM27/SUN biases for January 2015 of 0.03, 0.75, \u20130.12, and 2.43 % for X_(CO2), X_(CH4), X_(CO), and X_(N2)O respectively, with 1\u03c3 running precisions of 0.08 and 0.06 % for X_(CO2) and X_(CH4) from measurements in Pasadena. We also identify significant error caused by nonlinear sensitivity when using an extended spectral range detector used to measure CO and N_2O.", "date": "2016-08-03", "date_type": "published", "publication": "Atmospheric Measurement Techniques", "volume": "9", "number": "8", "publisher": "European Geosciences Union", "pagerange": "3527-3546", "id_number": "CaltechAUTHORS:20171017-154006422", "issn": "1867-8548", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20171017-154006422", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Keck Institute for Space Studies (KISS)" }, { "agency": "Dow Chemical Company" }, { "agency": "NASA", "grant_number": "NNX14AI60G" }, { "agency": "JPL" }, { "agency": "NSF", "grant_number": "AGS-1337512" }, { "agency": "Los Alamos National Laboratory" } ] }, "local_group": { "items": [ { "id": "Keck-Institute-for-Space-Studies" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/amt-9-3527-2016", "primary_object": { "basename": "amt-9-3527-2016.pdf", "url": "https://authors.library.caltech.edu/records/3prng-kzc28/files/amt-9-3527-2016.pdf" }, "resource_type": "article", "pub_year": "2016", "author_list": "Hedelius, Jacob K.; Viatte, Camille; et el." }, { "id": "https://authors.library.caltech.edu/records/cyw8b-5ss95", "eprint_id": 103514, "eprint_status": "archive", "datestamp": "2023-08-22 18:27:21", "lastmod": "2023-10-20 16:26:57", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Connor-B-J", "name": { "family": "Connor", "given": "Brian J." } }, { "id": "Sherlock-V", "name": { "family": "Sherlock", "given": "Vanessa" } }, { "id": "Toon-G-C", "name": { "family": "Toon", "given": "Geoff" }, "orcid": "0000-0003-4174-7541" }, { "id": "Wunch-D", "name": { "family": "Wunch", "given": "Debra" }, "orcid": "0000-0002-4924-0377" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "GFIT2: an experimental algorithm for vertical profile retrieval from near-IR spectra", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 Author(s) 2016. This work is distributed under\nthe Creative Commons Attribution 3.0 License. Published by Copernicus Publications on behalf of the European Geosciences Union. \n\nReceived: 27 August 2015 \u2013 Published in Atmos. Meas. Tech. Discuss.: 23 November 2015; Revised: 29 June 2016 \u2013 Accepted: 4 July 2016 \u2013 Published: 2 August 2016. \n\nPart of this research was performed at the Jet Propulsion Laboratory, California Institute of Technology, under contract with NASA. We thank NASA's Carbon Cycle Science Investigation Program for supporting the development of GFIT2 (NNX14AI60G). Operations of TCCON at Lamont, Oklahoma, are made possible by NASA's OCO-2 project in collaboration with the DOE ARM program. Cessna data from the SGP are available through the ARM archive (www.archive.arm.gov). We thank Sebastien Biraud for his assistance in interpreting the aircraft data. \n\nEdited by: F. Hase. Reviewed by: two anonymous referees.\n\nPublished - amt-9-3513-2016.pdf
", "abstract": "An algorithm for retrieval of vertical profiles from ground-based spectra in the near IR is described and tested. Known as GFIT2, the algorithm is primarily intended for CO\u2082, and is used exclusively for CO\u2082 in this paper. Retrieval of CO\u2082 vertical profiles from ground-based spectra is theoretically possible, would be very beneficial for carbon cycle studies and the validation of satellite measurements, and has been the focus of much research in recent years. GFIT2 is tested by application both to synthetic spectra and to measurements at two Total Carbon Column Observing Network (TCCON) sites. We demonstrate that there are approximately 3\u00b0 of freedom for the CO2 profile, and the algorithm performs as expected on synthetic spectra. We show that the accuracy of retrievals of CO\u2082 from measurements in the 1.61\u03bc (6220\u202fcm\u207b\u00b9) spectral band is limited by small uncertainties in calculation of the atmospheric spectrum. We investigate several techniques to minimize the effect of these uncertainties in calculation of the spectrum. These techniques are somewhat effective but to date have not been demonstrated to produce CO\u2082 profile retrievals with sufficient precision for applications to carbon dynamics. We finish by discussing ongoing research which may allow CO\u2082 profile retrievals with sufficient accuracy to significantly improve the scientific value of the measurements from that achieved with column retrievals.", "date": "2016-08-02", "date_type": "published", "publication": "Atmospheric Measurement Techniques", "volume": "9", "number": "8", "publisher": "European Geosciences Union", "pagerange": "3513-3525", "id_number": "CaltechAUTHORS:20200528-084127637", "issn": "1867-8548", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200528-084127637", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA/JPL/Caltech" }, { "agency": "NASA", "grant_number": "NNX14AI60G" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/amt-9-3513-2016", "primary_object": { "basename": "amt-9-3513-2016.pdf", "url": "https://authors.library.caltech.edu/records/cyw8b-5ss95/files/amt-9-3513-2016.pdf" }, "resource_type": "article", "pub_year": "2016", "author_list": "Connor, Brian J.; Sherlock, Vanessa; et el." }, { "id": "https://authors.library.caltech.edu/records/2zfm9-0x735", "eprint_id": 70955, "eprint_status": "archive", "datestamp": "2023-08-22 18:19:13", "lastmod": "2023-10-23 15:13:22", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Kaiser-J-B", "name": { "family": "Kaiser", "given": "J." } }, { "id": "Skog-K-M", "name": { "family": "Skog", "given": "K. M." } }, { "id": "Baumann-K", "name": { "family": "Baumann", "given": "K." } }, { "id": "Bertman-S-B", "name": { "family": "Bertman", "given": "S. B." } }, { "id": "Brown-S-B", "name": { "family": "Brown", "given": "S. B." } }, { "id": "Brune-W-H", "name": { "family": "Brune", "given": "W. H." }, "orcid": "0000-0002-1609-4051" }, { "id": "Crounse-J-D", "name": { "family": "Crounse", "given": "J. D." }, "orcid": "0000-0001-5443-729X" }, { "id": "de-Gouw-J-A", "name": { "family": "de Gouw", "given": "J. A." }, "orcid": "0000-0002-0385-1826" }, { "id": "Edgerton-E-S", "name": { "family": "Edgerton", "given": "E. S." } }, { "id": "Brown-P-A", "name": { "family": "Brown", "given": "P. A." } }, { "id": "Goldstein-A-H", "name": { "family": "Goldstein", "given": "A. H." }, "orcid": "0000-0003-4014-4896" }, { "id": "Koss-A", "name": { "family": "Koss", "given": "A." } }, { "id": "Misztal-P-K", "name": { "family": "Misztal", "given": "P. K." }, "orcid": "0000-0003-1060-1750" }, { "id": "Nguyen-T-B", "name": { "family": "Nguyen", "given": "T. B." } }, { "id": "Olson-K-F", "name": { "family": "Olson", "given": "K. F." } }, { "id": "St-Clair-J-M", "name": { "family": "St. Clair", "given": "J. M." }, "orcid": "0000-0002-9367-5749" }, { "id": "Teng-A-P", "name": { "family": "Teng", "given": "A. P." } }, { "id": "Toma-S", "name": { "family": "Toma", "given": "S." } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Wild-R-J", "name": { "family": "Wild", "given": "R. J." } }, { "id": "Zhang-L", "name": { "family": "Zhang", "given": "L." } }, { "id": "Keutsch-F-N", "name": { "family": "Keutsch", "given": "F. N." } } ] }, "title": "Speciation of OH reactivity above the canopy of an isoprene-dominated forest", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2016 Author(s). \u00a9 Author(s) 2016. This work is distributed\nunder the Creative Commons Attribution 3.0 License. \n\nReceived: 11 Dec 2015. Published in Atmos. Chem. Phys. Discuss.: 18 Jan 2016. Revised: 12 Jul 2016. Accepted: 12 Jul 2016. Published: 28 Jul 2016. \n\nThe authors would like to acknowledge contribution from all members of the SOAS science team. Funding was provided by US EPA \"Science to Achieve Results (STAR) program\" Grant 83540601. A. H. Goldstein and P. K. Misztal acknowledge support from EPA STAR Grant R835407. This research has not been subjected to any EPA review and therefore does not necessarily reflect the views of the Agency, and no official endorsement should be inferred. Additional funding was provided by NSF-grant AGS-1247421 and 1628530. J. Kaiser acknowledges support from NASA Headquarters under the NASA Earth and Space Science Fellowship Program \u2013 Grant NNX14AK97H. \n\nEdited by: N. L. Ng. Reviewed by: two anonymous referees.\n\nPublished - acp-16-9349-2016.pdf
", "abstract": "Measurements of OH reactivity, the inverse lifetime of the OH radical, can provide a top\u2013down estimate of the total amount of reactive carbon in an air mass. Using a comprehensive measurement suite, we examine the measured and modeled OH reactivity above an isoprene-dominated forest in the southeast United States during the 2013 Southern Oxidant and Aerosol Study (SOAS) field campaign. Measured and modeled species account for the vast majority of average daytime reactivity (80\u201395\u202f%) and a smaller portion of nighttime and early morning reactivity (68\u201380\u202f%). The largest contribution to total reactivity consistently comes from primary biogenic emissions, with isoprene contributing \u223c\u2009\u202f60\u202f% in the afternoon, and \u223c\u2009\u202f30\u201340\u202f% at night and monoterpenes contributing \u223c\u2009\u202f15\u201325\u202f% at night. By comparing total reactivity to the reactivity stemming from isoprene alone, we find that \u223c\u2009\u202f20\u202f% of the discrepancy is temporally related to isoprene reactivity, and an additional constant \u223c\u2009\u202f1\u202fs^(\u22121) offset accounts for the remaining portion. The model typically overestimates measured OVOC concentrations, indicating that unmeasured oxidation products are unlikely to influence measured OH reactivity. Instead, we suggest that unmeasured primary emissions may influence the OH reactivity at this site.", "date": "2016-07-18", "date_type": "published", "publication": "Atmospheric Chemistry and Physics", "volume": "16", "number": "14", "publisher": "Copernicus Publications", "pagerange": "9349-9359", "id_number": "CaltechAUTHORS:20161007-142943299", "issn": "1680-7316", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20161007-142943299", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Environmental Protection Agency (EPA)", "grant_number": "83540601" }, { "agency": "Environmental Protection Agency (EPA)", "grant_number": "R835407" }, { "agency": "NSF", "grant_number": "AGS-1247421" }, { "agency": "NSF", "grant_number": "AGS-1628530" }, { "agency": "NASA Earth and Space Science Fellowship", "grant_number": "NNX14AK97H" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/acp-16-9349-2016", "primary_object": { "basename": "acp-16-9349-2016.pdf", "url": "https://authors.library.caltech.edu/records/2zfm9-0x735/files/acp-16-9349-2016.pdf" }, "resource_type": "article", "pub_year": "2016", "author_list": "Kaiser, J.; Skog, K. M.; et el." }, { "id": "https://authors.library.caltech.edu/records/1v236-1dx26", "eprint_id": 70728, "eprint_status": "archive", "datestamp": "2023-08-22 18:18:55", "lastmod": "2023-10-20 23:26:41", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Chen-Jia", "name": { "family": "Chen", "given": "Jia" } }, { "id": "Viatte-C", "name": { "family": "Viatte", "given": "Camille" } }, { "id": "Hedelius-J-K", "name": { "family": "Hedelius", "given": "Jacob K." }, "orcid": "0000-0003-2025-7519" }, { "id": "Jones-T", "name": { "family": "Jones", "given": "Taylor" }, "orcid": "0000-0001-5860-3419" }, { "id": "Franklin-J-E", "name": { "family": "Franklin", "given": "Jonathan E." } }, { "id": "Parker-H", "name": { "family": "Parker", "given": "Harrison" } }, { "id": "Gottlieb-E-W", "name": { "family": "Gottlieb", "given": "Elaine W." } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Dubey-M-K", "name": { "family": "Dubey", "given": "Manvendra K." } }, { "id": "Wofsy-S-C", "name": { "family": "Wofsy", "given": "Steven C." }, "orcid": "0000-0002-3990-6737" } ] }, "title": "Differential column measurements using compact solar-tracking spectrometers", "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: 29 Dec 2015 \u2013 Published in Atmos. Chem. Phys. Discuss.: 17 Feb 2016. Revised: 06 Jun 2016 \u2013 Accepted: 08 Jun 2016 \u2013 Published: 12 Jul 2016. \n\nWe thank Bruce Daube and John Budney for the preparation of the measurement campaign in Chino and Pasadena and for building the weather stations and the enclosures for the spectrometers. We thank Frank Hase for help with the PROFFIT retrieval software, Matthias Frey for instructions on the ILS measurements, and Matth\u00e4us Kiel for the Calpy software. We thank Yanina Barrera for the lidar data and Frank Hase, Kelly Chance, Christoph Gerbig, Bruce Daube, John Budney, Bill Munger, Rachel Chang, and Kathryn McKain for fruitful discussions. Funding for this study was provided by the National Science Foundation through Major Research Instrumentation Award 1337512 \"Acquisition of Mesoscale Network of Surface Sensors and Solar-tracking Spectrometers\". Jia Chen was partly supported by Technische Universit\u00e4t M\u00fcnchen \u2013 Institute for Advanced Study, funded by the German Excellence Initiative and the European Union Seventh Framework Programme under grant agreement no. 291763. Harrison Parker and Manvendra K. Dubey (Los Alamos National Laboratory) acknowledge NASA's Carbon Monitoring Program for funding the EM27/SUN application development. The authors gratefully acknowledge the NOAA Air Resources Laboratory (ARL) for the provision of the HYSPLIT transport and dispersion model. The authors would also like to thank the anonymous reviewers for helpful comments. This work was supported by the German Research Foundation (DFG) and the Technische Universit\u00e4t M\u00fcnchen within the funding programme Open Access Publishing. \n\nEdited by: M. Heimann\n\nPublished - acp-16-8479-2016.pdf
", "abstract": "We demonstrate the use of compact solar-tracking Fourier transform spectrometers (Bruker EM27/SUN) for differential measurements of the column-averaged dry-air mole fractions of CH_4 and CO_2 within urban areas. Using Allan variance analysis, we show that the differential column measurement has a precision of 0.01\u202f% for X_(CO_2) and X_(CH_4) with an optimum integration time of 10\u202fmin, corresponding to Allan deviations of 0.04\u202fppm and 0.2\u202fppb,respectively. The sensor system is very stable over time and after relocation across the continent. We report tests of the differential column measurement,and its sensitivity to emission sources, by measuring the downwind-minus-upwind column difference \u0394X_(CH_4) across dairy farms in the Chino area, California, and using the data to verify emissions reported in the literature. Ratios of spatial column differences \u0394X_(CH_4)\u2215\u0394X_(CO_2) were observed across Pasadena within the Los Angeles basin, indicating values consistent with regional emission ratios from the literature. Our precise, rapid measurements allow us to determine significant short-term variations (5\u201310\u202fmin) of X_(CO_2) and X_(CH_4) and to show that they represent atmospheric phenomena.\n\nOverall, this study helps establish a range of new applicationsfor compact solar-viewing Fourier transform spectrometers. Byaccurately measuring the small differences in integrated column amounts acrosslocal and regional sources, we directly observe the mass loadingof the atmosphere due to the influence of emissions in theintervening locale. The inference of the source strength is muchmore direct than inversion modeling using only surface concentrationsand less subject to errors associated with small-scale transportphenomena.", "date": "2016-07-12", "date_type": "published", "publication": "Atmospheric Chemistry and Physics", "volume": "16", "number": "13", "publisher": "European Geosciences Union", "pagerange": "8479-8498", "id_number": "CaltechAUTHORS:20160930-152629323", "issn": "1680-7324", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160930-152629323", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "AGS-1337512" }, { "agency": "Technische Universit\u00e4t M\u00fcnchen" }, { "agency": "European Research Council (ERC)", "grant_number": "291763" }, { "agency": "Deutsche Forschungsgemeinschaft (DFG)" }, { "agency": "NASA" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/acp-16-8479-2016", "primary_object": { "basename": "acp-16-8479-2016.pdf", "url": "https://authors.library.caltech.edu/records/1v236-1dx26/files/acp-16-8479-2016.pdf" }, "resource_type": "article", "pub_year": "2016", "author_list": "Chen, Jia; Viatte, Camille; et el." }, { "id": "https://authors.library.caltech.edu/records/317mg-vxf37", "eprint_id": 66598, "eprint_status": "archive", "datestamp": "2023-08-22 18:15:05", "lastmod": "2023-10-18 18:37:08", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Brune-W-H", "name": { "family": "Brune", "given": "W. H." }, "orcid": "0000-0002-1609-4051" }, { "id": "Baier-B-C", "name": { "family": "Baier", "given": "B. C." } }, { "id": "Thomas-J", "name": { "family": "Thomas", "given": "J." } }, { "id": "Ren-Xinrong", "name": { "family": "Ren", "given": "X." } }, { "id": "Cohen-R-C", "name": { "family": "Cohen", "given": "R. C." }, "orcid": "0000-0001-6617-7691" }, { "id": "Pusede-S-E", "name": { "family": "Pusede", "given": "S. E." } }, { "id": "Browne-E-C", "name": { "family": "Browne", "given": "E. C." } }, { "id": "Goldstein-A-H", "name": { "family": "Goldstein", "given": "A. H." }, "orcid": "0000-0003-4014-4896" }, { "id": "Gentner-D-R", "name": { "family": "Gentner", "given": "D. R." } }, { "id": "Keutsch-F-N", "name": { "family": "Keutsch", "given": "F. N." } }, { "id": "Thornton-J-A", "name": { "family": "Thornton", "given": "J. A." }, "orcid": "0000-0002-5098-4867" }, { "id": "Harrold-S", "name": { "family": "Harrold", "given": "S." } }, { "id": "Lopez-Hilfiker-F-D", "name": { "family": "Lopez-Hilfiker", "given": "F. D." } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "Ozone production chemistry in the presence of urban plumes", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2016 The Royal Society of Chemistry. \n\nReceived 01 Dec 2015, Accepted 23 Dec 2015. First published online 23 Dec 2015. \n\nThis article is part of themed collection: Chemistry in the Urban Atmosphere. \n\nWe thank John Karlik, Rick Ramirez and the other scientists and staff at the University of California Kern County Extension Center for their hospitality and use of their facilities. Participation by WHB, BCB, JT was supported by grants from California Air Resources Board through the University of California, Berkeley (UCB subcontract 00007016) and from NSF (ATM-0706821).\n\nPublished - c5fd00204d.pdf
", "abstract": "Ozone pollution affects human health, especially in urban areas on hot sunny days. Its basic photochemistry has been known for decades and yet it is still not possible to correctly predict the high ozone levels that are the greatest threat. The CalNex_SJV study in Bakersfield CA in May/June 2010 provided an opportunity to examine ozone photochemistry in an urban area surrounded by agriculture. The measurement suite included hydroxyl (OH), hydroperoxyl (HO_2), and OH reactivity, which are compared with the output of a photochemical box model. While the agreement is generally within combined uncertainties, measured HO2 far exceeds modeled HO_2 in NO_x-rich plumes. OH production and loss do not balance as they should in the morning, and the ozone production calculated with measured HO_2 is a decade greater than that calculated with modeled HO_2 when NO levels are high. Calculated ozone production using measured HO2 is twice that using modeled HO_2, but this difference in calculated ozone production has minimal impact on the assessment of NOx-sensitivity or VOC-sensitivity for midday ozone production. Evidence from this study indicates that this important discrepancy is not due to the HO_2 measurement or to the sampling of transported plumes but instead to either emissions of unknown organic species that accompany the NO emissions or unknown photochemistry involving nitrogen oxides and hydrogen oxides, possibly the hypothesized reaction OH + NO + O_2 \u2192 HO_2 + NO_2.", "date": "2016-07-01", "date_type": "published", "publication": "Faraday Discussions", "volume": "189", "publisher": "Royal Society of Chemistry", "pagerange": "169-189", "id_number": "CaltechAUTHORS:20160502-143820468", "issn": "1359-6640", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160502-143820468", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "California Air Resources Board", "grant_number": "00007016" }, { "agency": "NSF", "grant_number": "ATM-0706821" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1039/C5FD00204D", "primary_object": { "basename": "c5fd00204d.pdf", "url": "https://authors.library.caltech.edu/records/317mg-vxf37/files/c5fd00204d.pdf" }, "resource_type": "article", "pub_year": "2016", "author_list": "Brune, W. H.; Baier, B. C.; et el." }, { "id": "https://authors.library.caltech.edu/records/k51sf-q1f27", "eprint_id": 69452, "eprint_status": "archive", "datestamp": "2023-08-22 18:08:57", "lastmod": "2023-10-20 19:04:26", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Romer-P-S", "name": { "family": "Romer", "given": "Paul S." }, "orcid": "0000-0002-4983-743X" }, { "id": "Duffey-K-C", "name": { "family": "Duffey", "given": "Kaitlin C." } }, { "id": "Wooldridge-P-J", "name": { "family": "Wooldridge", "given": "Paul J." } }, { "id": "Allen-H-M", "name": { "family": "Allen", "given": "Hannah M." } }, { "id": "Ayres-B-R", "name": { "family": "Ayres", "given": "Benjamin R." } }, { "id": "Brown-S-S", "name": { "family": "Brown", "given": "Steven S." } }, { "id": "Brune-W-H", "name": { "family": "Brune", "given": "William H." }, "orcid": "0000-0002-1609-4051" }, { "id": "Crounse-J-D", "name": { "family": "Crounse", "given": "John D." }, "orcid": "0000-0001-5443-729X" }, { "id": "de-Gouw-J-A", "name": { "family": "de Gouw", "given": "Joost" }, "orcid": "0000-0002-0385-1826" }, { "id": "Draper-D-C", "name": { "family": "Draper", "given": "Danielle C." } }, { "id": "Feiner-P-A", "name": { "family": "Feiner", "given": "Philip A." } }, { "id": "Fry-J-L", "name": { "family": "Fry", "given": "Juliane L." } }, { "id": "Goldstein-A-H", "name": { "family": "Goldstein", "given": "Allen H." }, "orcid": "0000-0003-4014-4896" }, { "id": "Koss-A", "name": { "family": "Koss", "given": "Abigail" } }, { "id": "Misztal-P-K", "name": { "family": "Misztal", "given": "Pawel K." }, "orcid": "0000-0003-1060-1750" }, { "id": "Nguyen-Tran-B", "name": { "family": "Nguyen", "given": "Tran B." } }, { "id": "Olson-K", "name": { "family": "Olson", "given": "Kevin" } }, { "id": "Teng-Alex-P", "name": { "family": "Teng", "given": "Alex P." } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Wild-R-J", "name": { "family": "Wild", "given": "Robert J." } }, { "id": "Zhang-Li", "name": { "family": "Zhang", "given": "Li" } }, { "id": "Cohen-R-C", "name": { "family": "Cohen", "given": "Ronald C." }, "orcid": "0000-0001-6617-7691" } ] }, "title": "The lifetime of nitrogen oxides in an isoprene-dominated forest", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 Author(s) 2016. CC Attribution 3.0 License. \n\nReceived 12 Jan 2016; published in Atmos. Chem. Phys. Discuss. 21 Jan 2016; revised 4 May 2016; accepted 16 May 2016; published 23 Jun 2016. \n\nFinancial and logistical support for SOAS was provided by the NSF, the Earth Observing Laboratory at the National Center for Atmospheric Research (operated by NSF), the personnel at Atmospheric Research and Analysis, and the Electric Power Research Institute. The Berkeley authors acknowledge the support of the NOAA Office of Global Programs (NA13OAR4310067) and the NSF (AGS-1352972) and by EPA STAR Grant 835407 (to Allen H. Goldstein). The Caltech authors acknowledge the support of the NSF (AGS-1331360, AGS-1240604). The Penn State authors acknowledge the support of the NSF (AGS-1246918). Ronald C. Cohen acknowledges support from the Miller Institute for Basic Research.\n\nPublished - acp-16-7623-2016.pdf
", "abstract": "The lifetime of nitrogen oxides (NO_x) affects the concentration and distribution of NO_x and the spatial patterns of nitrogen deposition. Despite its importance, the lifetime of NO_x is poorly constrained in rural and remote continental regions. We use measurements from a site in central Alabama during the Southern Oxidant and Aerosol Study (SOAS) in summer 2013 to provide new insights into the chemistry of NO_x and NO_x reservoirs. We find that the lifetime of NO_x during the daytime is controlled primarily by the production and loss of alkyl and multifunctional nitrates (\u03a3ANs). During SOAS, \u03a3AN production was rapid, averaging 90\u202fppt\u202fh^(\u22121) during the day, and occurred predominantly during isoprene oxidation. Analysis of the \u03a3AN and HNO_3 budgets indicate that \u03a3ANs have an average lifetime of under 2\u202fh, and that approximately 45\u202f% of the \u03a3ANs produced at this site are rapidly hydrolyzed to produce nitric acid. We find that \u03a3AN hydrolysis is the largest source of HNO_3 and the primary pathway to permanent removal of NO_x from the boundary layer in this location. Using these new constraints on the fate of \u03a3ANs, we find that the NO_x lifetime is 11\u2009\u00b1\u20095\u202fh under typical midday conditions. The lifetime is extended by storage of NO_x in temporary reservoirs, including acyl peroxy nitrates and \u03a3ANs.", "date": "2016-06-23", "date_type": "published", "publication": "Atmospheric Chemistry and Physics", "volume": "16", "number": "12", "publisher": "European Geosciences Union", "pagerange": "7623-7637", "id_number": "CaltechAUTHORS:20160804-150734787", "issn": "1680-7324", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160804-150734787", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "National Center for Atmospheric Research (NCAR)" }, { "agency": "Electric Power Research Institute (EPRI)" }, { "agency": "National Oceanic and Atmospheric Administration (NOAA)", "grant_number": "NA13OAR4310067" }, { "agency": "NSF", "grant_number": "AGS-1352972" }, { "agency": "Environmental Protection Agency (EPA)", "grant_number": "835407" }, { "agency": "NSF", "grant_number": "AGS-1331360" }, { "agency": "NSF", "grant_number": "AGS-1240604" }, { "agency": "NSF", "grant_number": "AGS-1246918" }, { "agency": "Miller Institute for Basic Research in Science" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/acp-16-7623-2016", "primary_object": { "basename": "acp-16-7623-2016.pdf", "url": "https://authors.library.caltech.edu/records/k51sf-q1f27/files/acp-16-7623-2016.pdf" }, "resource_type": "article", "pub_year": "2016", "author_list": "Romer, Paul S.; Duffey, Kaitlin C.; et el." }, { "id": "https://authors.library.caltech.edu/records/bpsjf-bqa40", "eprint_id": 70276, "eprint_status": "archive", "datestamp": "2023-08-22 18:05:18", "lastmod": "2023-10-20 22:05:51", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Liu-Xiaoxi", "name": { "family": "Liu", "given": "Xiaoxi" }, "orcid": "0000-0002-5104-8886" }, { "id": "St-Clair-J-M", "name": { "family": "St. Clair", "given": "J. M." }, "orcid": "0000-0002-9367-5749" }, { "id": "Crounse-J-D", "name": { "family": "Crounse", "given": "J. D." }, "orcid": "0000-0001-5443-729X" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "Agricultural fires in the southeastern U.S. during SEAC^4RS: Emissions of trace gases and particles and evolution of ozone, reactive nitrogen, and organic aerosol", "ispublished": "pub", "full_text_status": "public", "keywords": "biomass burning; agricultural fire; fire emissions; plume chemistry; oxidants; aerosols", "note": "\u00a9 2016 American Geophysical Union. \n\nReceived 4 Mar 2016. Accepted 25 May 2016. Accepted article online 28 May 2016. Published online 22 Jun 2016. \n\nThis work was supported by NASA grant NNX12AB77G. R. Yokelson was supported by NASA Earth Science Division Awards NNX12AC20G and NNX14AP45G. PTR-MS measurements during SEAC^4RS were supported by the Austrian Federal Ministry for Transport, Innovation and Technology (bmvit) through the Austrian Space Applications Programme (ASAP) of the Austrian Research Promotion Agency (FFG). A.W. and T.M. received support from the Visiting Scientist Program at the National Institute of Aerospace (NIA). P.C.J., D.A.D., and J.L.J. were supported by NNX12AC03G and NNX15AT96G. CIT-CIMS measurements were supported by NASA grants NNX12AC06G and NNX14AP46G-ACCDAM. ISAF HCHO observations were supported by NASA SEAC^4RS grant NNH10ZDA001N. The authors would also like to thank the SEAC^4RS science team and the DC-8 flight crews. Data from the SEAC^4RS mission can be found at http://www-air.larc.nasa.gov/cgi-bin/ArcView/seac4rs and http://www-air.larc.nasa.gov/missions/seac4rs/index.html.\n\nPublished - Liu_et_al-2016-Journal_of_Geophysical_Research__Atmospheres.pdf
Supplemental Material - jgrd53048-sup-0001-Supplementary.pdf
", "abstract": "Emissions from 15 agricultural fires in the southeastern U.S. were measured from the NASA DC-8 research aircraft during the summer 2013 Studies of Emissions and Atmospheric Composition, Clouds and Climate Coupling by Regional Surveys (SEAC^4RS) campaign. This study reports a detailed set of emission factors (EFs) for 25 trace gases and 6 fine particle species. The chemical evolution of the primary emissions in seven plumes was examined in detail for ~1.2\u2009h. A Lagrangian plume cross-section model was used to simulate the evolution of ozone (O_3), reactive nitrogen species, and organic aerosol (OA). Observed EFs are generally consistent with previous measurements of crop residue burning, but the fires studied here emitted high amounts of SO_2 and fine particles, especially primary OA and chloride. Filter-based measurements of aerosol light absorption implied that brown carbon (BrC) was ubiquitous in the plumes. In aged plumes, rapid production of O_3, peroxyacetyl nitrate (PAN), and nitrate was observed with \u0394O_3/\u0394CO, \u0394PAN/\u0394NO_y, and \u0394nitrate/\u0394NO_y reaching ~0.1, ~0.3, and ~0.3. For five selected cases, the model reasonably simulated O_3 formation but underestimated PAN formation. No significant evolution of OA mass or BrC absorption was observed. However, a consistent increase in oxygen-to-carbon (O/C) ratios of OA indicated that OA oxidation in the agricultural fire plumes was much faster than in urban and forest fire plumes. Finally, total annual SO_2, NO_x, and CO emissions from agricultural fires in Arkansas, Louisiana, Mississippi, and Missouri were estimated (within a factor of ~2) to be equivalent to ~2% SO_2 from coal combustion and ~1% NO_x and ~9% CO from mobile sources.", "date": "2016-06", "date_type": "published", "publication": "Journal of Geophysical Research. Atmospheres", "volume": "121", "number": "12", "publisher": "American Geophysical Union", "pagerange": "7383-7414", "id_number": "CaltechAUTHORS:20160912-094736849", "issn": "2169-897X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160912-094736849", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NNX12AB77G" }, { "agency": "NASA", "grant_number": "NNX12AC20G" }, { "agency": "NASA", "grant_number": "NNX14AP45G" }, { "agency": "Bundesministerium f\u00fcr Verkehr, Innovation und Technologie (BMVIT)" }, { "agency": "Austrian Space Applications Programme (ASAP)" }, { "agency": "National Institute of Aerospace (NIA)" }, { "agency": "NASA", "grant_number": "NNX12AC03G" }, { "agency": "NASA", "grant_number": "NNX15AT96G" }, { "agency": "NASA", "grant_number": "NNX12AC06G" }, { "agency": "NASA", "grant_number": "NNX14AP46G-ACCDAM" }, { "agency": "NASA", "grant_number": "NNH10ZDA001N" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1002/2016JD025040", "primary_object": { "basename": "Liu_et_al-2016-Journal_of_Geophysical_Research__Atmospheres.pdf", "url": "https://authors.library.caltech.edu/records/bpsjf-bqa40/files/Liu_et_al-2016-Journal_of_Geophysical_Research__Atmospheres.pdf" }, "related_objects": [ { "basename": "jgrd53048-sup-0001-Supplementary.pdf", "url": "https://authors.library.caltech.edu/records/bpsjf-bqa40/files/jgrd53048-sup-0001-Supplementary.pdf" } ], "resource_type": "article", "pub_year": "2016", "author_list": "Liu, Xiaoxi; St. Clair, J. M.; et el." }, { "id": "https://authors.library.caltech.edu/records/dc4g6-1hm67", "eprint_id": 68657, "eprint_status": "archive", "datestamp": "2023-08-22 17:59:44", "lastmod": "2023-10-19 22:24:49", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Fisher-J-A", "name": { "family": "Fisher", "given": "Jenny A." } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Crounse-J-D", "name": { "family": "Crounse", "given": "John D." }, "orcid": "0000-0001-5443-729X" }, { "id": "Teng-Alex-P", "name": { "family": "Teng", "given": "Alex P." } }, { "id": "Nguyen-Tran-B", "name": { "family": "Nguyen", "given": "Tran B." } }, { "id": "St-Clair-J-M", "name": { "family": "St. Clair", "given": "Jason M." }, "orcid": "0000-0002-9367-5749" } ] }, "title": "Organic nitrate chemistry and its implications for nitrogen budgets in an isoprene- and monoterpene-rich atmosphere: constraints from aircraft (SEAC^4RS) and ground-based (SOAS) observations in the Southeast US", "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: 18 January 2016. Published in Atmos. Chem. Phys. Discuss.: 4 February 2016. Revised: 27 April 2016. Accepted: 29 April 2016. Published: 17 May 2016. \n\nWe are grateful to the entire NASA SEAC4RS team for their help in the field, and we thank Eleanor Browne and Fabien Paulot for helpful discussions about the monoterpene nitrate\nscheme. This work was funded by a University of Wollongong Vice Chancellor's Postdoctoral Fellowship to J. A. Fisher and by the NASA Tropospheric Chemistry Program. This research was undertaken with the assistance of resources provided at the NCI National Facility systems at the Australian National University through the National Computational Merit Allocation Scheme supported by\nthe Australian Government. J. Mao acknowledges supports from\nthe NOAA Climate Program Office grant NA13OAR4310071.\nJ. L. Jimenez, P. Campuzano-Jost, W. Hu, and D. A. Day were\nsupported by NASA NNX15AH33A and NNX15AT96G, NSF\nAGS-1243354 and AGS-1360834, and EPRI 10004734. Isoprene\nand monoterpene measurements during SEAC4RS were supported by the Austrian Federal Ministry for Transport, Innovation and Technology (bmvit) through the Austrian Space Applications Programme (ASAP) of the Austrian Research Promotion Agency (FFG). A. Wisthaler and T. Mikoviny received support from the Visiting Scientist Program at the National Institute of Aerospace (NIA).\n\nPublished - acp-16-5969-2016.pdf
Accepted Version - nihms952687.pdf
Supplemental Material - acp-16-5969-2016-supplement.pdf
", "abstract": "Formation of organic nitrates (RONO_2) during oxidation of biogenic volatile organic compounds (BVOCs: isoprene, monoterpenes) is a significant loss pathway for atmospheric nitrogen oxide radicals (NO_x), but the chemistry of RONO_2 formation and degradation remains uncertain. Here we implement a new BVOC oxidation mechanism (including updated isoprene chemistry, new monoterpene chemistry, and particle uptake of RONO_2) in the GEOS-Chem global chemical transport model with \u2009\u223c\u2009\u202f25\u202f\u2009\u00d7\u2009\u202f25\u202fkm^2 resolution over North America. We evaluate the model using aircraft (SEAC^4RS) and ground-based (SOAS) observations of NO_x, BVOCs, and RONO_2 from the Southeast US in summer 2013. The updated simulation successfully reproduces the concentrations of individual gas- and particle-phase RONO_2 species measured during the campaigns. Gas-phase isoprene nitrates account for 25\u201350\u202f% of observed RONO_2 in surface air, and we find that another 10\u202f% is contributed by gas-phase monoterpene nitrates. Observations in the free troposphere show an important contribution from long-lived nitrates derived from anthropogenic VOCs. During both campaigns, at least 10\u202f% of observed boundary layer RONO_2 were in the particle phase. We find that aerosol uptake followed by hydrolysis to HNO_3 accounts for 60\u202f% of simulated gas-phase RONO_2 loss in the boundary layer. Other losses are 20\u202f% by photolysis to recycle NO_x and 15\u202f% by dry deposition. RONO_2 production accounts for 20\u202f% of the net regional NO_x sink in the Southeast US in summer, limited by the spatial segregation between BVOC and NO_x emissions. This segregation implies that RONO_2 production will remain a minor sink for NO_x in the Southeast US in the future even as NO_x emissions continue to decline.", "date": "2016-05-17", "date_type": "published", "publication": "Atmospheric Chemistry and Physics", "volume": "16", "number": "9", "publisher": "European Geosciences Union", "pagerange": "5969-5991", "id_number": "CaltechAUTHORS:20160624-104423152", "issn": "1680-7316", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160624-104423152", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "University of Wollongong" }, { "agency": "Australian Government" }, { "agency": "National Oceanic and Atmospheric Administration (NOAA)", "grant_number": "NA13OAR4310071" }, { "agency": "NASA", "grant_number": "NNX15AH33A" }, { "agency": "NASA", "grant_number": "NNX15AT96G" }, { "agency": "NSF", "grant_number": "AGS-1243354" }, { "agency": "NSF", "grant_number": "AGS-1360834" }, { "agency": "NSF", "grant_number": "EPRI 10004734" }, { "agency": "Bundesministerium f\u00fcr Verkehr, Innovation und Technologie (BMVIT)" }, { "agency": "Austrian Space Applications Programme (ASAP)" }, { "agency": "Austrian Research Promotion Agency (FFG)" }, { "agency": "National Institute of Aerospace (NIA)" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/acp-16-5969-2016", "pmcid": "PMC5906813", "primary_object": { "basename": "acp-16-5969-2016-supplement.pdf", "url": "https://authors.library.caltech.edu/records/dc4g6-1hm67/files/acp-16-5969-2016-supplement.pdf" }, "related_objects": [ { "basename": "acp-16-5969-2016.pdf", "url": "https://authors.library.caltech.edu/records/dc4g6-1hm67/files/acp-16-5969-2016.pdf" }, { "basename": "nihms952687.pdf", "url": "https://authors.library.caltech.edu/records/dc4g6-1hm67/files/nihms952687.pdf" } ], "resource_type": "article", "pub_year": "2016", "author_list": "Fisher, Jenny A.; Wennberg, Paul O.; et el." }, { "id": "https://authors.library.caltech.edu/records/6qj8v-d9y67", "eprint_id": 69104, "eprint_status": "archive", "datestamp": "2023-08-22 17:53:29", "lastmod": "2023-10-23 20:16:45", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Dupuy-E", "name": { "family": "Dupuy", "given": "Eric" } }, { "id": "Roehl-C-M", "name": { "family": "Roehl", "given": "Coleen M." }, "orcid": "0000-0001-5383-8462" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "Comparison of XH_2O Retrieved from GOSAT Short-Wavelength Infrared Spectra with Observations from the TCCON Network", "ispublished": "pub", "full_text_status": "public", "keywords": "GOSAT; H2O; SWIR; validation", "note": "\u00a9 2016 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\nAcademic Editors: Alfredo R. Huete and Prasad S. Thenkabail. \n\nReceived: 10 January 2016; Accepted: 4 May 2016; Published: 17 May 2016. \n\nThis paper is essential for the NIES GOSAT Project Office to ensure the qualification of the GOSAT TANSO-FTS SWIR XH_2O data as a standard product. Nicholas Deutscher is supported by an Australian Research Council fellowship, DE140100178. TCCON data were obtained from the TCCON Data Archive, hosted by the Carbon Dioxide Information Analysis Center (CDIAC): http://tccon.ornl.gov. The TCCON Network is supported by NASA through a grant to the California Institute of Technology: NNX14AI60G. Park Falls, Lamont and JPL are funded by NASA grants NNX14AI60G, NNX11AG01G, NAG5-12247, NNG05-GD07G and the NASA Orbiting Carbon Observatory Program. We are grateful to the United States of America's Department of Energy (DOE) Atmospheric Radiation Measurement (ARM) program for technical support in Lamont and to Jeff Ayers for technical support in Park Falls. Darwin and Wollongong are funded by NASA grants NAG5-12247 and NNG05-GD07G and the Australian Research Council grants DP140101552, DP110103118, DP0879468, LE0668470 and LP0562346. We are grateful to the DOE ARM program for technical support in Darwin. Bremen, Bialystok and Orl\u00e9ans are funded by the European Union's projects InGOS (Integrated non-CO_2 Greenhouse gas Observing System) and ICOS-INWIRE (Integrated Carbon Observing System-Improved sensors, Network and Interoperability for GMES (Global Monitoring for Environment and Security)) and by the Senate of Bremen. From 2004\u20132011, the Lauder TCCON program was funded by the New Zealand Foundation of Research, Science and Technology contracts CO1X0204, CO1X0703 and CO1X0406. Since 2011, the program has been funded by New Zealand's National Institute of Water and Atmospheric Research (NIWA)'s Atmosphere Research Programme 3 (2011/2013 Statement of Corporate Intent). Garmisch water vapor retrievals have been supported by the Bavarian Ministry of the Environment and Consumer Protection. Indianapolis and Edwards measurements are supported by the NASA Earth Science Division. \n\nAuthor Contributions: Eric Dupuy performed all of the NIES/TCCON comparisons for XH_2O presented in this paper within the NIES GOSAT Project, produced the figures and tables and wrote the entire paper. Nicholas Deutscher conducted the counterpart XH_2O comparisons among the TCCON partners; he collaborated closely throughout this analysis and the conception of the paper. Isamu Morino leads the GOSAT/GOSAT-2 Validation Team and took extensive part in the data analysis and the writing and review of this paper. Yukio Yoshida is responsible for the Level 2 processing of the GOSAT SWIR data at NIES; he was instrumental in the interpretation of the validation results from the point of view of retrieval biases. Osamu Uchino is the GOSAT Validation Manager and oversees the validation for all GOSAT data products at NIES, including XH2_O\nVersion V02.21. Tatsuya Yokota and Tsuneo Matsunaga are the NIES Project Leaders for GOSAT and GOSAT-2, respectively, and coordinate all aspects of the GOSAT and GOSAT-2 Projects within NIES. Other authors are members of the TCCON Steering Committee and principal investigators or co-investigators of TCCON stations; they contributed to the acquisition, processing and delivery of the TCCON data products for the sites included in this study. All authors provided feedback on the data analysis and the writing of this manuscript. \n\nThe authors declare no conflict of interest.\n\nPublished - remotesensing-08-00414-v2.pdf
Supplemental Material - remotesensing-08-00414-s001.zip
Erratum - remotesensing-08-00982.pdf
", "abstract": "Understanding the atmospheric distribution of water (H_2O) is crucial for global warming studies and climate change mitigation. In this context, reliable satellite data are extremely valuable for their global and continuous coverage, once their quality has been assessed. Short-wavelength infrared spectra are acquired by the Thermal And Near-infrared Sensor for carbon Observation-Fourier Transform Spectrometer (TANSO-FTS) aboard the Greenhouse gases Observing Satellite (GOSAT). From these, column-averaged dry-air mole fractions of carbon dioxide, methane and water vapor (XH_2O) have been retrieved at the National Institute for Environmental Studies (NIES, Japan) and are available as a Level 2 research product. We compare the NIES XH_2O data, Version 02.21, with retrievals from the ground-based Total Carbon Column Observing Network (TCCON, Version GGG2014). The datasets are in good overall agreement, with GOSAT data showing a slight global low bias of \u22123.1% \u00b1 24.0%, good consistency over different locations (station bias of \u22121.53% \u00b1 10.35%) and reasonable correlation with TCCON (R = 0.89). We identified two potential sources of discrepancy between the NIES and TCCON retrievals over land. While the TCCON XH_2O amounts can reach 6000\u20137000 ppm when the atmospheric water content is high, the correlated NIES values do not exceed 5500 ppm. This could be due to a dry bias of TANSO-FTS in situations of high humidity and aerosol content. We also determined that the GOSAT-TCCON differences directly depend on the altitude difference between the TANSO-FTS footprint and the TCCON site. Further analysis will account for these biases, but the NIES V02.21 XH_2O product, after public release, can already be useful for water cycle studies.", "date": "2016-05", "date_type": "published", "publication": "Remote Sensing", "volume": "8", "number": "5", "publisher": "MDPI", "pagerange": "Art. No. 414", "id_number": "CaltechAUTHORS:20160719-074158502", "issn": "2072-4292", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160719-074158502", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Australian Research Council", "grant_number": "DE140100178" }, { "agency": "NASA", "grant_number": "NNX14AI60G" }, { "agency": "NASA", "grant_number": "NNX11AG01G" }, { "agency": "NASA", "grant_number": "NAG5-12247" }, { "agency": "NASA", "grant_number": "NNG05-GD07G" }, { "agency": "Australian Research Council", "grant_number": "DP140101552" }, { "agency": "Australian Research Council", "grant_number": "DP110103118" }, { "agency": "Australian Research Council", "grant_number": "DP0879468" }, { "agency": "Australian Research Council", "grant_number": "LE0668470" }, { "agency": "Australian Research Council", "grant_number": "LP0562346" }, { "agency": "European Union" }, { "agency": "Senate of Bremen" }, { "agency": "New Zealand Foundation of Research, Science and Technology", "grant_number": "CO1X0204" }, { "agency": "New Zealand Foundation of Research, Science and Technology", "grant_number": "CO1X0703" }, { "agency": "New Zealand Foundation of Research, Science and Technology", "grant_number": "CO1X0406" }, { "agency": "New Zealand National Institute of Water and Atmospheric Research" }, { "agency": "Ministry of the Environment and Consumer Protection (Bavaria)" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.3390/rs8050414", "primary_object": { "basename": "remotesensing-08-00414-s001.zip", "url": "https://authors.library.caltech.edu/records/6qj8v-d9y67/files/remotesensing-08-00414-s001.zip" }, "related_objects": [ { "basename": "remotesensing-08-00414-v2.pdf", "url": "https://authors.library.caltech.edu/records/6qj8v-d9y67/files/remotesensing-08-00414-v2.pdf" }, { "basename": "remotesensing-08-00982.pdf", "url": "https://authors.library.caltech.edu/records/6qj8v-d9y67/files/remotesensing-08-00982.pdf" } ], "resource_type": "article", "pub_year": "2016", "author_list": "Dupuy, Eric; Roehl, Coleen M.; et el." }, { "id": "https://authors.library.caltech.edu/records/0mmev-e8s19", "eprint_id": 69046, "eprint_status": "archive", "datestamp": "2023-08-22 17:49:59", "lastmod": "2023-10-20 16:28:30", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Barth-M-C", "name": { "family": "Barth", "given": "M. C." } }, { "id": "Bela-M-M", "name": { "family": "Bela", "given": "M. M." } }, { "id": "Fried-A", "name": { "family": "Fried", "given": "A." } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Crounse-J-D", "name": { "family": "Crounse", "given": "J. D." }, "orcid": "0000-0001-5443-729X" }, { "id": "St-Clair-J-M", "name": { "family": "St. Clair", "given": "J. M." }, "orcid": "0000-0002-9367-5749" }, { "id": "Blake-N-J", "name": { "family": "Blake", "given": "N. J." } }, { "id": "Blake-D-R", "name": { "family": "Blake", "given": "D. R." } }, { "id": "Homeyer-C-R", "name": { "family": "Homeyer", "given": "C. R." } }, { "id": "Brune-W-H", "name": { "family": "Brune", "given": "W. H." }, "orcid": "0000-0002-1609-4051" }, { "id": "Zhang-L", "name": { "family": "Zhang", "given": "L." } }, { "id": "Mao-J", "name": { "family": "Mao", "given": "J." } }, { "id": "Ren-Xinrong", "name": { "family": "Ren", "given": "X." } }, { "id": "Ryerson-T-B", "name": { "family": "Ryerson", "given": "T. B." }, "orcid": "0000-0003-2800-7581" }, { "id": "Pollack-I-B", "name": { "family": "Pollack", "given": "I. B." }, "orcid": "0000-0001-7151-9756" }, { "id": "Peischl-J", "name": { "family": "Peischl", "given": "J." }, "orcid": "0000-0002-9320-7101" }, { "id": "Cohen-R-C", "name": { "family": "Cohen", "given": "R. C." }, "orcid": "0000-0001-6617-7691" }, { "id": "Nault-B-A", "name": { "family": "Nault", "given": "B. A." }, "orcid": "0000-0001-9464-4787" }, { "id": "Huey-L-G", "name": { "family": "Huey", "given": "L. G." }, "orcid": "0000-0002-0518-7690" }, { "id": "Liu-Xiaoxi", "name": { "family": "Liu", "given": "X." }, "orcid": "0000-0002-5104-8886" }, { "id": "Cantrell-C-A", "name": { "family": "Cantrell", "given": "C. A." } } ] }, "title": "Convective transport and scavenging of peroxides by thunderstorms observed over the central U.S. during DC3", "ispublished": "pub", "full_text_status": "public", "keywords": "thunderstorms and chemistry; scavenging of peroxides", "note": "\u00a9 2016 American Geophysical Union. \n\nReceived 25 NOV 2015; Accepted 10 APR 2016; Accepted article online 13 APR 2016; Published online 29 APR 2016. \n\nThe authors thank the DC3 Science and Logistics teams for the successful execution of the DC3 field campaign. Data from the DC3 field project can be found at http://data.eol.ucar.edu/master_list/?project=DC3. The aircraft data are also located at http://www-air.larc.nasa.gov/cgi-bin/ArcView/dc3-seac4rs. Output from the model simulations can be obtained upon request to M. Barth (barthm@ucar.edu). We appreciate Conrad Ziegler (NOAA/NSSL) and his team as well as the NCAR/EOL ISS team for the radiosonde data. G. Diskin and his team are acknowledged for their DC-8 water vapor and CO measurements. We are grateful for the informative weather summaries provided by Morris Weisman and Craig Schwartz during the DC3 field campaign. We value the contributions of John Orlando and the comments on the paper by Sasha Madronich, Rebecca Hornbrook and the three anonymous reviewers. The National Center for Atmospheric Research is sponsored by the National Science Foundation. The INSTAAR group acknowledges NSF and NASA under grant awards AGS-1261559 and NNX12AMO8G, respectively, for funding their participation in the measurements and analysis. The Caltech group thanks NASA for funding their participation in DC3 and contribution to this analysis via grants NNX12AC06G and NNX14AP46G-ACCDAM. N. Blake and D. Blake acknowledge support for DC3 measurements from NASA award NNX12AB76G. C. Homeyer was supported by NSF under grant AGS-1522910. W. H. Brune, L. Zhang, J. Mao, and X. Ren were supported by NASA grant NNX12AB84G. T. B. Ryerson, J. Peischl, and I. B. Pollack were supported under the NOAA Climate Change and NOAA Health of the Atmosphere programs, with participation in DC3 made possible by NASA grant NNH12AT30I. R. C. Cohen and B. A. Nault were supported by NASA grant NNX12AB79G. B. A. Nault was also supported by the NSF Graduate Research Fellowship under grant DGE 1106400. L. G. Huey and X. Liu were supported by NASA grant NNX12AB77G.\n\nPublished - Barth_et_al-2016-Journal_of_Geophysical_Research__Atmospheres.pdf
", "abstract": "One of the objectives of the Deep Convective Clouds and Chemistry (DC3) field experiment was to determine the scavenging of soluble trace gases by thunderstorms. We present an analysis of scavenging of hydrogen peroxide (H_2O_2) and methyl hydrogen peroxide (CH_3OOH) from six DC3 cases that occurred in Oklahoma and northeast Colorado. Estimates of H_2O_2 scavenging efficiencies are comparable to previous studies ranging from 79 to 97% with relative uncertainties of 5\u201325%. CH_3OOH scavenging efficiencies ranged from 12 to 84% with relative uncertainties of 18\u2013558%. The wide range of CH_3OOH scavenging efficiencies is surprising, as previous studies suggested that CH_3OOH scavenging efficiencies would be <10%. Cloud chemistry model simulations of one DC3 storm produced CH_3OOH scavenging efficiencies of 26\u201361% depending on the ice retention factor of CH_3OOH during cloud drop freezing, suggesting ice physics impacts CH_3OOH scavenging. The highest CH_3OOH scavenging efficiencies occurred in two severe thunderstorms, but there is no obvious correlation between the CH_3OOH scavenging efficiency and the storm thermodynamic environment. We found a moderate correlation between the estimated entrainment rates and CH_3OOH scavenging efficiencies. Changes in gas-phase chemistry due to lightning production of nitric oxide and aqueous-phase chemistry have little effect on CH_3OOH scavenging efficiencies. To determine why CH_3OOH can be substantially removed from storms, future studies should examine effects of entrainment rate, retention of CH_3OOH in frozen cloud particles during drop freezing, and lightning-NO_x production.", "date": "2016-04-27", "date_type": "published", "publication": "Journal of Geophysical Research. Atmospheres", "volume": "121", "number": "8", "publisher": "American Geophysical Union", "pagerange": "4272-4295", "id_number": "CaltechAUTHORS:20160715-084034753", "issn": "2169-897X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160715-084034753", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "AGS-1261559" }, { "agency": "NASA", "grant_number": "NNX12AMO8G" }, { "agency": "NASA", "grant_number": "NNX12AC06G" }, { "agency": "NASA", "grant_number": "NNX14AP46G-ACCDAM" }, { "agency": "NASA", "grant_number": "NNX12AB76G" }, { "agency": "NSF", "grant_number": "AGS-1522910" }, { "agency": "NASA", "grant_number": "NNX12AB84G" }, { "agency": "National Oceanic and Atmospheric Administration (NOAA)" }, { "agency": "NASA", "grant_number": "NNH12AT30I" }, { "agency": "NASA", "grant_number": "NNX12AB79G" }, { "agency": "NSF Graduate Research Fellowship", "grant_number": "DGE-1106400" }, { "agency": "NASA", "grant_number": "NNX12AB77G" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1002/2015JD024570", "primary_object": { "basename": "Barth_et_al-2016-Journal_of_Geophysical_Research__Atmospheres.pdf", "url": "https://authors.library.caltech.edu/records/0mmev-e8s19/files/Barth_et_al-2016-Journal_of_Geophysical_Research__Atmospheres.pdf" }, "resource_type": "article", "pub_year": "2016", "author_list": "Barth, M. C.; Bela, M. M.; et el." }, { "id": "https://authors.library.caltech.edu/records/ww5cb-bn292", "eprint_id": 69109, "eprint_status": "archive", "datestamp": "2023-08-22 17:50:19", "lastmod": "2023-10-20 16:33:02", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Bela-M-M", "name": { "family": "Bela", "given": "Megan M." } }, { "id": "Barth-M-C", "name": { "family": "Barth", "given": "Mary C." } }, { "id": "Toon-O-B", "name": { "family": "Toon", "given": "Owen B." } }, { "id": "Fried-A", "name": { "family": "Fried", "given": "Alan" } }, { "id": "Homeyer-C-R", "name": { "family": "Homeyer", "given": "Cameron R." } }, { "id": "Morrison-H", "name": { "family": "Morrison", "given": "Hugh" }, "orcid": "0000-0001-8480-9787" }, { "id": "Cummings-K-A", "name": { "family": "Cummings", "given": "Kristin A." } }, { "id": "Li-Yunyao", "name": { "family": "Li", "given": "Yunyao" } }, { "id": "Pickering-K-E", "name": { "family": "Pickering", "given": "Kenneth E." } }, { "id": "Allen-D-J", "name": { "family": "Allen", "given": "Dale J." } }, { "id": "Yang-Qing", "name": { "family": "Yang", "given": "Qing" } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Crounse-J-D", "name": { "family": "Crounse", "given": "John D." }, "orcid": "0000-0001-5443-729X" }, { "id": "St-Clair-J-M", "name": { "family": "St. Clair", "given": "Jason M." }, "orcid": "0000-0002-9367-5749" }, { "id": "Teng-Alex-P", "name": { "family": "Teng", "given": "Alex P." } }, { "id": "O'Sullivan-D", "name": { "family": "O'Sullivan", "given": "Daniel" } }, { "id": "Huey-L-G", "name": { "family": "Huey", "given": "L. Gregory" }, "orcid": "0000-0002-0518-7690" }, { "id": "Chen-Dexian", "name": { "family": "Chen", "given": "Dexian" } }, { "id": "Liu-Xiaoxi", "name": { "family": "Liu", "given": "Xiaoxi" }, "orcid": "0000-0002-5104-8886" }, { "id": "Blake-D-R", "name": { "family": "Blake", "given": "Donald R." } }, { "id": "Blake-N-J", "name": { "family": "Blake", "given": "Nicola J." } }, { "id": "Apel-E-C", "name": { "family": "Apel", "given": "Eric C." } }, { "id": "Hornbrook-R-S", "name": { "family": "Hornbrook", "given": "Rebecca S." } }, { "id": "Flocke-F", "name": { "family": "Flocke", "given": "Frank" } }, { "id": "Campos-T", "name": { "family": "Campos", "given": "Teresa" } }, { "id": "Diskin-G-S", "name": { "family": "Diskin", "given": "Glenn" }, "orcid": "0000-0002-3617-0269" } ] }, "title": "Wet scavenging of soluble gases in DC3 deep convective storms using WRF-Chem simulations and aircraft observations", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2016 American Geophysical Union. \n\nReceived 8 DEC 2015; Accepted 26 MAR 2016; Accepted article online 2 APR 2016; Published online 21 APR 2016. \n\nWe express our appreciation to the following researchers for the aircraft observations: T. Ryerson and the NOAA NO_yO_3 team; Andrew Weinheimer; Mark Zondlo, Josh DiGangi, and Anthony O'Brien for the VCSEL hygrometer water vapor measurements on the GV; and P. Lawson and S. Woods from SPEC Inc. We also thank A. Weinheimer and M. Zondlo for their helpful feedback on this manuscript. M.M. Bela and O.B. Toon were supported by NASA ACCDAM-NNX14AR56G. The National Center for Atmospheric Research is sponsored by the National Science Foundation. A. Fried was supported by NSF and NASA under grants AGS-1261559 and NNX12AMO8G, respectively. C. Homeyer was funded by NSF grant AGS-1522910. The University of Maryland co-authors were supported under NSF grants 1063479 and 1522551. Q. Yang was supported by the Office of Science of the U.S. Department of Energy as part of the Atmospheric System Research Program (ASR). P.O. Wennberg, J.D. Crounse, A.P. Teng, and J.M. St. Clair thank NASA for supporting their contribution to this study (NNX12AC06G and NNX14AP46G-ACCDAM). D. O'Sullivan thanks NSF for support from grant ATM1063467. L.G. Huey, D. Chen, and X. Liu were funded by NASA grant NNX12AB77G. DC3 measurements by N. Blake and D. Blake were supported by NASA award NNX12AB76G. We would like to thank Earth Networks for providing the ENTLN lightning data for research purposes. The data used in this study can be downloaded from the following websites: 1 s data merges from the NASA Langley DC3 Merged Aircraft Dataset Archive (http://www-air.larc.nasa.gov/cgi-bin/ArcView/dc3); NEXRAD data for individual radars from the National Climatic Data Center (NCDC; http://has.ncdc.noaa.gov/pls/plhas/has.dsselect); NSSL-MGAUS sounding data (http://data.eol.ucar.edu/codiac/dss/id=353.105); NCEP Stage IV precipitation analysis (http://www.emc.ncep.noaa.gov/mmb/ylin/pcpanl/stage4/); and NAM-ANL (http://nomads.ncdc.noaa.gov/data/namanl/). The WRF-Chem code and land surface data are available for download from NCAR/MMM (http://www.mmm.ucar.edu/wrf/users/download/get_sources_wps_geog.html). WRF-Chem model output is available upon request to M.M. Bela (megan.bela@colorado.edu).\n\nPublished - Bela_et_al-2016-Journal_of_Geophysical_Research__Atmospheres.pdf
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Supplemental Material - jgrd52886-sup-0009-supinfo.tex
", "abstract": "We examine wet scavenging of soluble trace gases in storms observed during the Deep Convective Clouds and Chemistry (DC3) field campaign. We conduct high-resolution simulations with the Weather Research and Forecasting model with Chemistry (WRF-Chem) of a severe storm in Oklahoma. The model represents well the storm location, size, and structure as compared with Next Generation Weather Radar reflectivity, and simulated CO transport is consistent with aircraft observations. Scavenging efficiencies (SEs) between inflow and outflow of soluble species are calculated from aircraft measurements and model simulations. Using a simple wet scavenging scheme, we simulate the SE of each soluble species within the error bars of the observations. The simulated SEs of all species except nitric acid (HNO_3) are highly sensitive to the values specified for the fractions retained in ice when cloud water freezes. To reproduce the observations, we must assume zero ice retention for formaldehyde (CH_2O) and hydrogen peroxide (H_2O_2) and complete retention for methyl hydrogen peroxide (CH_3OOH) and sulfur dioxide (SO_2), likely to compensate for the lack of aqueous chemistry in the model. We then compare scavenging efficiencies among storms that formed in Alabama and northeast Colorado and the Oklahoma storm. Significant differences in SEs are seen among storms and species. More scavenging of HNO_3 and less removal of CH_3OOH are seen in storms with higher maximum flash rates, an indication of more graupel mass. Graupel is associated with mixed-phase scavenging and lightning production of nitrogen oxides (NO_x), processes that may explain the observed differences in HNO_3 and CH_3OOH scavenging.", "date": "2016-04-27", "date_type": "published", "publication": "Journal of Geophysical Research. Atmospheres", "volume": "121", "number": "8", "publisher": "American Geophysical Union", "pagerange": "4233-4257", "id_number": "CaltechAUTHORS:20160719-104230695", "issn": "2169-897X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160719-104230695", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "ACCDAM-NNX14AR56G" }, { "agency": "NSF", "grant_number": "AGS-1261559" }, { "agency": "NASA", "grant_number": "NNX12AMO8G" }, { "agency": "NSF", "grant_number": "AGS-1522910" }, { "agency": "NSF", "grant_number": "AGS-1063479" }, { "agency": "NSF", "grant_number": "AGS-1522551" }, { "agency": "Department of Energy (DOE)" }, { "agency": "NASA", "grant_number": "NNX12AC06G" }, { "agency": "NASA", "grant_number": "NNX14AP46G-ACCDAM" }, { "agency": "NSF", "grant_number": "ATM-1063467" }, { "agency": "NASA", "grant_number": "NNX12AB77G" }, { "agency": "NASA", "grant_number": "NNX12AB76G" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1002/2015JD024623", "primary_object": { "basename": "Bela_et_al-2016-Journal_of_Geophysical_Research__Atmospheres.pdf", "url": "https://authors.library.caltech.edu/records/ww5cb-bn292/files/Bela_et_al-2016-Journal_of_Geophysical_Research__Atmospheres.pdf" }, "related_objects": [ { "basename": "jgrd52886-sup-0001-supinfo.png", "url": "https://authors.library.caltech.edu/records/ww5cb-bn292/files/jgrd52886-sup-0001-supinfo.png" }, { "basename": "jgrd52886-sup-0004-supinfo.png", "url": "https://authors.library.caltech.edu/records/ww5cb-bn292/files/jgrd52886-sup-0004-supinfo.png" }, { "basename": "jgrd52886-sup-0006-supinfo.png", "url": "https://authors.library.caltech.edu/records/ww5cb-bn292/files/jgrd52886-sup-0006-supinfo.png" }, { "basename": "jgrd52886-sup-0007-supinfo.png", "url": "https://authors.library.caltech.edu/records/ww5cb-bn292/files/jgrd52886-sup-0007-supinfo.png" }, { "basename": "jgrd52886-sup-0002-supinfo.png", "url": "https://authors.library.caltech.edu/records/ww5cb-bn292/files/jgrd52886-sup-0002-supinfo.png" }, { "basename": "jgrd52886-sup-0003-supinfo.png", "url": "https://authors.library.caltech.edu/records/ww5cb-bn292/files/jgrd52886-sup-0003-supinfo.png" }, { "basename": "jgrd52886-sup-0005-supinfo.png", "url": "https://authors.library.caltech.edu/records/ww5cb-bn292/files/jgrd52886-sup-0005-supinfo.png" }, { "basename": "jgrd52886-sup-0008-supinfo.png", "url": "https://authors.library.caltech.edu/records/ww5cb-bn292/files/jgrd52886-sup-0008-supinfo.png" }, { "basename": "jgrd52886-sup-0009-supinfo.tex", "url": "https://authors.library.caltech.edu/records/ww5cb-bn292/files/jgrd52886-sup-0009-supinfo.tex" } ], "resource_type": "article", "pub_year": "2016", "author_list": "Bela, Megan M.; Barth, Mary C.; et el." }, { "id": "https://authors.library.caltech.edu/records/vzxzy-xky13", "eprint_id": 65907, "eprint_status": "archive", "datestamp": "2023-08-22 17:49:34", "lastmod": "2023-10-18 16:55:16", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Nguyen-Tran-B", "name": { "family": "Nguyen", "given": "Tran B." } }, { "id": "Tyndall-G-S", "name": { "family": "Tyndall", "given": "Geoffrey S." } }, { "id": "Crounse-J-D", "name": { "family": "Crounse", "given": "John D." }, "orcid": "0000-0001-5443-729X" }, { "id": "Teng-Alexander-P", "name": { "family": "Teng", "given": "Alexander P." }, "orcid": "0000-0002-6434-0501" }, { "id": "Bates-K-H", "name": { "family": "Bates", "given": "Kelvin H." }, "orcid": "0000-0001-7544-9580" }, { "id": "Schwantes-R-H", "name": { "family": "Schwantes", "given": "Rebecca H." }, "orcid": "0000-0002-7095-3718" }, { "id": "Coggon-M-M", "name": { "family": "Coggon", "given": "Matthew M." }, "orcid": "0000-0002-5763-1925" }, { "id": "Zhang-Li", "name": { "family": "Zhang", "given": "Li" } }, { "id": "Feiner-P", "name": { "family": "Feiner", "given": "Philip" } }, { "id": "Milller-D-O", "name": { "family": "Milller", "given": "David O." } }, { "id": "Skog-K-M", "name": { "family": "Skog", "given": "Kate M." } }, { "id": "Rivera-Rios-J-C", "name": { "family": "Rivera-Rios", "given": "Jean C." } }, { "id": "Dorris-M", "name": { "family": "Dorris", "given": "Matthew" } }, { "id": "Olson-K-F", "name": { "family": "Olson", "given": "Kevin F." } }, { "id": "Koss-A", "name": { "family": "Koss", "given": "Abigail" } }, { "id": "Wild-R-J", "name": { "family": "Wild", "given": "Robert J." } }, { "id": "Brown-S-S", "name": { "family": "Brown", "given": "Steven S." } }, { "id": "Goldstein-A-H", "name": { "family": "Goldstein", "given": "Allen H." }, "orcid": "0000-0003-4014-4896" }, { "id": "de-Gouw-J-A", "name": { "family": "de Gouw", "given": "Joost A." }, "orcid": "0000-0002-0385-1826" }, { "id": "Brune-W-H", "name": { "family": "Brune", "given": "William H." }, "orcid": "0000-0002-1609-4051" }, { "id": "Keutsch-F-N", "name": { "family": "Keutsch", "given": "Frank N." } }, { "id": "Seinfeld-J-H", "name": { "family": "Seinfeld", "given": "John H." }, "orcid": "0000-0003-1344-4068" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "Atmospheric fates of Criegee intermediates in the ozonolysis of isoprene", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2016 Owner Societies. \n\nReceived 4th January 2016, Accepted 16th March 2016. First published online 16 Mar 2016. \n\nFunding for this work was provided by the U.S. National Science Foundation (NSF) Postdoctoral Research Fellowship award AGS-1331360, NSF grant AGS-1240604, and the Electric Power Research Institute grant EPRI-10003903. We thank the organizers and participants of the FIXCIT chamber campaign and SOAS field campaign.\n\nPublished - c6cp00053c.pdf
Supplemental Material - c6cp00053c1.pdf
", "abstract": "We use a large laboratory, modeling, and field dataset to investigate the isoprene + O_3 reaction, with the goal of better understanding the fates of the C_1 and C_4 Criegee intermediates in the atmosphere. Although ozonolysis can produce several distinct Criegee intermediates, the C_1 stabilized Criegee (CH_2OO, 61 \u00b1 9%) is the only one observed to react bimolecularly. We suggest that the C_4 Criegees have a low stabilization fraction and propose pathways for their decomposition. Both prompt and non-prompt reactions are important in the production of OH (28% \u00b1 5%) and formaldehyde (81% \u00b1 16%). The yields of unimolecular products (OH, formaldehyde, methacrolein (42 \u00b1 6%) and methyl vinyl ketone (18 \u00b1 6%)) are fairly insensitive to water, i.e., changes in yields in response to water vapor (\u22644% absolute) are within the error of the analysis. We propose a comprehensive reaction mechanism that can be incorporated into atmospheric models, which reproduces laboratory data over a wide range of relative humidities. The mechanism proposes that CH_2OO + H_2O (k_((H_2O)) \u223c 1 \u00d7 10^(\u221215) cm^3 molec^(\u22121) s^(\u22121)) yields 73% hydroxymethyl hydroperoxide (HMHP), 6% formaldehyde + H_2O_2, and 21% formic acid + H_2O; and CH_2OO + (H_2O)_2 (k_((H_2O)_2) \u223c 1 \u00d7 10^(\u221212) cm^3 molec^(\u22121) s^(\u22121)) yields 40% HMHP, 6% formaldehyde + H_2O_2, and 54% formic acid + H_2O. Competitive rate determinations (k_(SO_2/k(H_2O)n=1,2) \u223c 2.2 (\u00b10.3) \u00d7 10^4) and field observations suggest that water vapor is a sink for greater than 98% of CH2OO in a Southeastern US forest, even during pollution episodes ([SO_2] \u223c 10 ppb). The importance of the CH_2OO + (H_2O)n reaction is demonstrated by high HMHP mixing ratios observed over the forest canopy. We find that CH_2OO does not substantially affect the lifetime of SO_2 or HCOOH in the Southeast US, e.g., CH_2OO + SO_2 reaction is a minor contribution (<6%) to sulfate formation. Extrapolating, these results imply that sulfate production by stabilized Criegees is likely unimportant in regions dominated by the reactivity of ozone with isoprene. In contrast, hydroperoxide, organic acid, and formaldehyde formation from isoprene ozonolysis in those areas may be significant.", "date": "2016-04-21", "date_type": "published", "publication": "Physical Chemistry Chemical Physics", "volume": "18", "number": "15", "publisher": "Royal Society of Chemistry", "pagerange": "10241-10254", "id_number": "CaltechAUTHORS:20160404-151740437", "issn": "1463-9076", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160404-151740437", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF Postdoctoral Fellowship", "grant_number": "AGS-1331360" }, { "agency": "NSF", "grant_number": "AGS-1240604" }, { "agency": "Electric Power Research Institute (EPRI)", "grant_number": "EPRI-10003903" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1039/C6CP00053C", "primary_object": { "basename": "c6cp00053c1.pdf", "url": "https://authors.library.caltech.edu/records/vzxzy-xky13/files/c6cp00053c1.pdf" }, "related_objects": [ { "basename": "c6cp00053c.pdf", "url": "https://authors.library.caltech.edu/records/vzxzy-xky13/files/c6cp00053c.pdf" } ], "resource_type": "article", "pub_year": "2016", "author_list": "Nguyen, Tran B.; Tyndall, Geoffrey S.; et el." }, { "id": "https://authors.library.caltech.edu/records/wavkc-87y91", "eprint_id": 67193, "eprint_status": "archive", "datestamp": "2023-08-22 17:45:09", "lastmod": "2023-10-18 20:56:20", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Yu-Karen", "name": { "family": "Yu", "given": "Karen" } }, { "id": "Jacob-D-J", "name": { "family": "Jacob", "given": "Daniel J." }, "orcid": "0000-0002-6373-3100" }, { "id": "Fisher-J-A", "name": { "family": "Fisher", "given": "Jenny A." } }, { "id": "Kim-Patrick-S", "name": { "family": "Kim", "given": "Patrick S." } }, { "id": "Marais-E-A", "name": { "family": "Marais", "given": "Eloise A." }, "orcid": "0000-0001-5477-8051" }, { "id": "Miller-C-C", "name": { "family": "Miller", "given": "Christopher C." } }, { "id": "Travis-K-R", "name": { "family": "Travis", "given": "Katherine R." }, "orcid": "0000-0003-1628-0353" }, { "id": "Zhu-Lei", "name": { "family": "Zhu", "given": "Lei" } }, { "id": "Yantosca-R-M", "name": { "family": "Yantosca", "given": "Robert M." } }, { "id": "Sulprizio-M-P", "name": { "family": "Sulprizio", "given": "Melissa P." }, "orcid": "0000-0003-4641-5546" }, { "id": "Cohen-R-C", "name": { "family": "Cohen", "given": "Ron C." }, "orcid": "0000-0001-6617-7691" }, { "id": "Dibb-J-E", "name": { "family": "Dibb", "given": "Jack E." }, "orcid": "0000-0003-3096-7709" }, { "id": "Fried-A", "name": { "family": "Fried", "given": "Alan" } }, { "id": "Mikoviny-T", "name": { "family": "Mikoviny", "given": "Tomas" } }, { "id": "Ryerson-T-B", "name": { "family": "Ryerson", "given": "Thomas B." }, "orcid": "0000-0003-2800-7581" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Wisthaler-A", "name": { "family": "Wisthaler", "given": "Armin" } } ] }, "title": "Sensitivity to grid resolution in the ability of a chemical transport model to simulate observed oxidant chemistry under high-isoprene conditions", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 Author(s) 2016. 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: 05 Dec 2015. Published in Atmos. Chem. Phys. Discuss.: 18 Jan 2016. Revised: 26 Mar 2016. Accepted: 29 Mar 2016. Published: 07 Apr 2016. Edited by: M. C. Facchini. \n\nWe are grateful to the entire NASA SEAC^4RS team for their help in the field. This work was funded by the NASA Atmospheric Composition Modeling and Analysis Program and by the NASA Tropospheric Chemistry Program. Jenny A. Fisher acknowledges financial support from a University of Wollongong Vice Chancellor's Postdoctoral Fellowship. Isoprene measurements during SEAC^4RS were supported by the Austrian Federal Ministry for Transport, Innovation and Technology (bmvit) through the Austrian Space Applications Programme (ASAP) of the Austrian Research Promotion Agency (FFG). Armin Wisthaler and Tomas Mikoviny received support from the Visiting Scientist Program at the National Institute of Aerospace (NIA).\n\nPublished - acp-16-4369-2016.pdf
", "abstract": "Formation of ozone and organic aerosol in continental atmospheres depends on whether isoprene emitted by vegetation is oxidized by the high-NO_x pathway (where peroxy radicals react with NO) or by low-NO_x pathways (where peroxy radicals react by alternate channels, mostly with HO_2). We used mixed layer observations from the SEAC^4RS aircraft campaign over the Southeast US to test the ability of the GEOS-Chem chemical transport model at different grid resolutions (0.25\u00b0\u202f\u2009\u00d7\u2009\u202f0.3125\u00b0, 2\u00b0\u202f\u2009\u00d7\u2009\u202f2.5\u00b0, 4\u00b0\u202f\u2009\u00d7\u2009\u202f5\u00b0) to simulate this chemistry under high-isoprene, variable-NO_x conditions. Observations of isoprene and NO_x over the Southeast US show a negative correlation, reflecting the spatial segregation of emissions; this negative correlation is captured in the model at 0.25\u00b0\u202f\u2009\u00d7\u2009\u202f0.3125\u00b0 resolution but not at coarser resolutions. As a result, less isoprene oxidation takes place by the high-NO_x pathway in the model at 0.25\u00b0\u202f\u2009\u00d7\u2009\u202f0.3125\u00b0 resolution (54\u202f%) than at coarser resolution (59\u202f%). The cumulative probability distribution functions (CDFs) of NO_x, isoprene, and ozone concentrations show little difference across model resolutions and good agreement with observations, while formaldehyde is overestimated at coarse resolution because excessive isoprene oxidation takes place by the high-NO_x pathway with high formaldehyde yield. The good agreement of simulated and observed concentration variances implies that smaller-scale non-linearities (urban and power plant plumes) are not important on the regional scale. Correlations of simulated vs. observed concentrations do not improve with grid resolution because finer modes of variability are intrinsically more difficult to capture. Higher model resolution leads to decreased conversion of NO_x to organic nitrates and increased conversion to nitric acid, with total reactive nitrogen oxides (NO_y) changing little across model resolutions. Model concentrations in the lower free troposphere are also insensitive to grid resolution. The overall low sensitivity of modeled concentrations to grid resolution implies that coarse resolution is adequate when modeling continental boundary layer chemistry for global applications.", "date": "2016-04-04", "date_type": "published", "publication": "Atmospheric Chemistry and Physics Discussions", "volume": "16", "number": "7", "publisher": "European Geosciences Union", "pagerange": "4369-4378", "id_number": "CaltechAUTHORS:20160519-143211547", "issn": "1680-7367", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160519-143211547", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA" }, { "agency": "Austrian Space Applications Programme (ASAP)" }, { "agency": "\u00d6sterreichische Forschungsf\u00f6rderungsgesellschaft (FFG)" }, { "agency": "National Institute of Aerospace (NIA)" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/acp-16-4369-2016", "primary_object": { "basename": "acp-16-4369-2016.pdf", "url": "https://authors.library.caltech.edu/records/wavkc-87y91/files/acp-16-4369-2016.pdf" }, "resource_type": "article", "pub_year": "2016", "author_list": "Yu, Karen; Jacob, Daniel J.; et el." }, { "id": "https://authors.library.caltech.edu/records/pfee1-24360", "eprint_id": 65348, "eprint_status": "archive", "datestamp": "2023-08-22 17:34:20", "lastmod": "2023-10-18 14:33:48", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Donahue-N-M", "name": { "family": "Donahue", "given": "Neil M." } }, { "id": "Dubey-M-K", "name": { "family": "Dubey", "given": "Manvendra K." } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Brune-W-H", "name": { "family": "Brune", "given": "William H." }, "orcid": "0000-0002-1609-4051" } ] }, "title": "James G. Anderson Tribute", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 2016 American Chemical Society. \n\nPublished: March 10, 2016. \n\nThis article is part of the James G. Anderson Festschrift special issue.", "abstract": "The most important event in the history of atmospheric\nchemistry, and arguably environmental science, was the\ndiscovery and subsequent diagnosis of the Antarctic ozone hole.\nThe pinnacle of that research was the \"smoking gun\" figure\npublished by Anderson, Toohey, and Brune [Science, 1991,\nDOI: 10.1126/science.251.4989.39], reproduced here in Figure\n1. That plot, based on measurements of chlorine monoxide\n(ClO), ozone (O_3), and other species on the NASA ER-2\naircraft in 1987, helped galvanize international resolve to\nremove reactive halogens from the stratosphere, leading first to\nthe London amendments to the Montreal Protocol when the\ndata were known in preliminary form and then to the\nCopenhagen amendments once the final results were published.\nWithout that action, the global ramifications of ozone loss\ntoday would be catastrophic, and increases in the radiative\nforcing by chlorofluorcarbons would have led to even larger\nchanges in global climate.", "date": "2016-03-10", "date_type": "published", "publication": "Journal of Physical Chemistry A", "volume": "120", "number": "9", "publisher": "American Chemical Society", "pagerange": "1317-1319", "id_number": "CaltechAUTHORS:20160315-084412785", "issn": "1089-5639", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160315-084412785", "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/acs.jpca.5b11957", "resource_type": "article", "pub_year": "2016", "author_list": "Donahue, Neil M.; Dubey, Manvendra K.; et el." }, { "id": "https://authors.library.caltech.edu/records/9dys4-smn05", "eprint_id": 60402, "eprint_status": "archive", "datestamp": "2023-08-22 17:34:12", "lastmod": "2023-10-24 16:31:15", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "St-Clair-J-M", "name": { "family": "St. Clair", "given": "Jason M." }, "orcid": "0000-0002-9367-5749" }, { "id": "Rivera-Rios-J-C", "name": { "family": "Rivera-Rios", "given": "Jean C." } }, { "id": "Crounse-J-D", "name": { "family": "Crounse", "given": "John D." }, "orcid": "0000-0001-5443-729X" }, { "id": "Knap-H-C", "name": { "family": "Knap", "given": "Hasse C." } }, { "id": "Bates-K-H", "name": { "family": "Bates", "given": "Kelvin H." }, "orcid": "0000-0001-7544-9580" }, { "id": "Teng-Alex-P", "name": { "family": "Teng", "given": "Alex P." } }, { "id": "J\u00f8rgensen-S", "name": { "family": "J\u00f8rgensen", "given": "Solvejg" } }, { "id": "Kjaergaard-H-G", "name": { "family": "Kjaergaard", "given": "Henrik G." }, "orcid": "0000-0002-7275-8297" }, { "id": "Keutsch-F-N", "name": { "family": "Keutsch", "given": "Frank N." } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "Kinetics and Products of the Reaction of the First-Generation Isoprene Hydroxy Hydroperoxide (ISOPOOH) with OH", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2015 American Chemical Society. \n\nReceived: July 7, 2015; Revised: September 1, 2015; Publication Date (Web): September 1, 2015. \n\nSpecial Issue: James G. Anderson Festschrift. \n\nJ.M.S.C., J.D.C., A.T., K.H.B., and P.O.W. thank the National Science Foundation (AGS-1240604) and NASA (NNX14AP46G-ACCDAM) for supporting this work. Development of the GC-ToF-CIMS is supported by an award from the National Science Foundation's Major Research Instrumentation Program (AGS-1428482). J.C.R. and F.N.K. acknowledge support from NSF Grant AGS 1247421 and 1321987. H.C.K., S.J., and H.G.K. thank the Danish Council for Independent Research\u2014Natural Sciences, and the Danish Center for Scientific Computing for funding. \n\nThe authors declare no competing financial interest.\n\nSupplemental Material - jp5b06532_si_001.pdf
", "abstract": "The atmospheric oxidation of isoprene by the OH radical leads to the formation of several isomers of an unsaturated hydroxy hydroperoxide, ISOPOOH. Oxidation of ISOPOOH by OH produces epoxydiols, IEPOX, which have been shown to contribute mass to secondary organic aerosol (SOA). We present kinetic rate constant measurements for OH + ISOPOOH using synthetic standards of the two major isomers: (1,2)- and (4,3)-ISOPOOH. At 297 K, the total OH rate constant is 7.5 \u00b1 1.2 \u00d7 10^(\u201311) cm^3 molecule^(\u20131) s^(\u20131) for (1,2)-ISOPOOH and 1.18 \u00b1 0.19 \u00d7 10^(\u201310) cm^3 molecule^(\u20131) s^(\u20131) for (4,3)-ISOPOOH. Abstraction of the hydroperoxy hydrogen accounts for approximately 12% and 4% of the reactivity for (1,2)-ISOPOOH and (4,3)-ISOPOOH, respectively. The sum of all H-abstractions account for approximately 15% and 7% of the reactivity for (1,2)-ISOPOOH and (4,3)-ISOPOOH, respectively. The major product observed from both ISOPOOH isomers was IEPOX (cis-\u03b2 and trans-\u03b2 isomers), with a \u223c 2:1 preference for trans-\u03b2 IEPOX and similar total yields from each ISOPOOH isomer (\u223c70\u201380%). An IEPOX global production rate of more than 100 Tg C each year is estimated from this chemistry using a global 3D chemical transport model, similar to earlier estimates. Finally, following addition of OH to ISOPOOH, approximately 13% of the reactivity proceeds via addition of O_2 at 297 K and 745 Torr. In the presence of NO, these peroxy radicals lead to formation of small carbonyl compounds. Under HO_2 dominated chemistry, no products are observed from these channels. We suggest that the major products, highly oxygenated organic peroxides, are lost to the chamber walls. In the atmosphere, formation of these compounds may contribute to organic aerosol mass.", "date": "2016-03-10", "date_type": "published", "publication": "Journal of Physical Chemistry A", "volume": "120", "number": "9", "publisher": "American Chemical Society", "pagerange": "1441-1451", "id_number": "CaltechAUTHORS:20150922-075145239", "issn": "1089-5639", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150922-075145239", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "AGS-1240604" }, { "agency": "NASA", "grant_number": "NNX14AP46G-ACCDAM" }, { "agency": "NSF", "grant_number": "AGS-1428482" }, { "agency": "NSF", "grant_number": "AGS 1247421" }, { "agency": "NSF", "grant_number": "AGS-1321987" }, { "agency": "Danish Council for Independent Research-Natural Sciences" }, { "agency": "Danish Center for Scientific Computing" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1021/acs.jpca.5b06532", "primary_object": { "basename": "jp5b06532_si_001.pdf", "url": "https://authors.library.caltech.edu/records/9dys4-smn05/files/jp5b06532_si_001.pdf" }, "resource_type": "article", "pub_year": "2016", "author_list": "St. Clair, Jason M.; Rivera-Rios, Jean C.; et el." }, { "id": "https://authors.library.caltech.edu/records/ksr33-nfv78", "eprint_id": 66026, "eprint_status": "archive", "datestamp": "2023-08-22 17:34:50", "lastmod": "2023-10-18 17:04:09", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Nault-B-A", "name": { "family": "Nault", "given": "Benjamin A." }, "orcid": "0000-0001-9464-4787" }, { "id": "Garland-C", "name": { "family": "Garland", "given": "Charity" } }, { "id": "Wooldridge-P-J", "name": { "family": "Wooldridge", "given": "Paul J." } }, { "id": "Brune-W-H", "name": { "family": "Brune", "given": "William H." }, "orcid": "0000-0002-1609-4051" }, { "id": "Campuzano-Jost-P", "name": { "family": "Campuzano-Jost", "given": "Pedro" }, "orcid": "0000-0003-3930-010X" }, { "id": "Crounse-J-D", "name": { "family": "Crounse", "given": "John D." }, "orcid": "0000-0001-5443-729X" }, { "id": "Day-D-A", "name": { "family": "Day", "given": "Douglas A." }, "orcid": "0000-0003-3213-4233" }, { "id": "Dibb-J-E", "name": { "family": "Dibb", "given": "Jack" }, "orcid": "0000-0003-3096-7709" }, { "id": "Hall-S-R", "name": { "family": "Hall", "given": "Samuel R." }, "orcid": "0000-0002-2060-7112" }, { "id": "Huey-G", "name": { "family": "Huey", "given": "Gregory" } }, { "id": "Jimenez-J-L", "name": { "family": "Jimenez", "given": "Jos\u00e9 L." }, "orcid": "0000-0001-6203-1847" }, { "id": "Liu-Xiaoxi", "name": { "family": "Liu", "given": "Xiaoxi" }, "orcid": "0000-0002-5104-8886" }, { "id": "Mao-Jingqiu", "name": { "family": "Mao", "given": "Jingqiu" } }, { "id": "Mikoviny-T", "name": { "family": "Mikoviny", "given": "Tomas" } }, { "id": "Peischl-J", "name": { "family": "Peischl", "given": "Jeff" }, "orcid": "0000-0002-9320-7101" }, { "id": "Pollack-I-B", "name": { "family": "Pollack", "given": "Ilana B." }, "orcid": "0000-0001-7151-9756" }, { "id": "Ren-Xinrong", "name": { "family": "Ren", "given": "Xinrong" } }, { "id": "Ryerson-T-B", "name": { "family": "Ryerson", "given": "Thomas B." }, "orcid": "0000-0003-2800-7581" }, { "id": "Scheuer-E", "name": { "family": "Scheuer", "given": "Eric" } }, { "id": "Ullmann-K", "name": { "family": "Ullmann", "given": "Kirk" }, "orcid": "0000-0002-4724-9634" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Wisthaler-A", "name": { "family": "Wisthaler", "given": "Armin" } }, { "id": "Zhang-Li", "name": { "family": "Zhang", "given": "Li" } }, { "id": "Cohen-R-C", "name": { "family": "Cohen", "given": "Ronald C." }, "orcid": "0000-0001-6617-7691" } ] }, "title": "Observational Constraints on the Oxidation of NO_x in the Upper Troposphere", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2015 American Chemical Society. \n\nReceived 11 August 2015; published online 17 November 2015; published in print 10 March 2016. \n\nBAN was supported by the National Science Foundation Graduate Research Fellowship under grant no. DGE 1106400. BAN, CG, PWJ, and RCC acknowledge funding support from NASA (NNX12AB79G). PTR-MS measurements aboard the NASA DC-8 were supported by the Austrian Federal Ministry for Transport, Innovation and Technology (bmvit) through the Austrian Space Applications Programme (ASAP) of the Austrian Research Promotion Agency (FFG). TM was supported by an appointment to the NASA Postdoctoral Program at the Langley Research Center, administered by Oak Ridge Associated Universities through a contract with NASA. JDC and POW acknowledge funding support from NASA (NNX12AC06G and NNX14AP46G). PCJ and JLJ acknowledge funding form NASA (NNX12AC03G and NNX15AH33A). JD and ES acknowledge funding from NASA (NNX12AB80G). BAN would like to thank Joshua L. Laughner in his assistance in setting up and running the GEOS-Chem model. The authors also want to thank the ground and flight crews of the DC-8 and the DC3 science team. Finally, the authors want to thank Donald Blake for the use of the whole air sampler measurements, Glenn Diskin for the use of the CH_4 observations, and the reviewers for their constructive and thoughtful comments.\n\nSupplemental Material - jp5b07824_si_001.pdf
", "abstract": "NO_x (NO_x \u2261 NO + NO_2) regulates O_3 and HO_x (HO_x \u2261 OH + HO_2) concentrations in the upper troposphere. In the laboratory, it is difficult to measure rates and branching ratios of the chemical reactions affecting NO_x at the low temperatures and pressures characteristic of the upper troposphere, making direct measurements in the atmosphere especially useful. We report quasi-Lagrangian observations of the chemical evolution of an air parcel following a lightning event that results in high NO_x concentrations. These quasi-Lagrangian measurements obtained during the Deep Convective Clouds and Chemistry experiment are used to characterize the daytime rates for conversion of NOx to different peroxy nitrates, the sum of alkyl and multifunctional nitrates, and HNO_3. We infer the following production rate constants [in (cm^3/molecule)/s] at 225 K and 230 hPa: 7.2(\u00b15.7) \u00d7 10^(\u201312) (CH_3O_2NO_2), 5.1(\u00b13.1) \u00d7 10^(\u201313) (HO_2NO_2), 1.3(\u00b10.8) \u00d7 10^(\u201311) (PAN), 7.3(\u00b13.4) \u00d7 10^(\u201312) (PPN), and 6.2(\u00b12.9) \u00d7 10^(\u201312) (HNO_3). The HNO_3 and HO_2NO_2 rates are \u223c30\u201350% lower than currently recommended whereas the other rates are consistent with current recommendations to within \u00b130%. The analysis indicates that HNO_3 production from the HO_2 and NO reaction (if any) must be accompanied by a slower rate for the reaction of OH with NO_2, keeping the total combined rate for the two processes at the rate reported for HNO_3 production above.", "date": "2016-03-10", "date_type": "published", "publication": "Journal of Physical Chemistry A", "volume": "120", "number": "9", "publisher": "American Chemical Society", "pagerange": "1468-1478", "id_number": "CaltechAUTHORS:20160408-121404439", "issn": "1089-5639", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160408-121404439", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF Graduate Research Fellowship", "grant_number": "DGE 1106400" }, { "agency": "NASA", "grant_number": "NNX12AB79G" }, { "agency": "Bundesministerium f\u00fcr Verkehr, Innovation und Technologie (BMVIT)" }, { "agency": "\u00d6sterreichische Forschungsf\u00f6rderungsgesellschaft (FFG)" }, { "agency": "NASA Postdoctoral Program" }, { "agency": "NASA", "grant_number": "NNX12AC06G" }, { "agency": "NASA", "grant_number": "NNX14AP46G" }, { "agency": "NASA", "grant_number": "NNX12AC03G" }, { "agency": "NASA", "grant_number": "NNX15AH33A" }, { "agency": "NASA", "grant_number": "NNX12AB80G" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1021/acs.jpca.5b07824", "primary_object": { "basename": "jp5b07824_si_001.pdf", "url": "https://authors.library.caltech.edu/records/ksr33-nfv78/files/jp5b07824_si_001.pdf" }, "resource_type": "article", "pub_year": "2016", "author_list": "Nault, Benjamin A.; Garland, Charity; et el." }, { "id": "https://authors.library.caltech.edu/records/f0g3b-f1643", "eprint_id": 67840, "eprint_status": "archive", "datestamp": "2023-08-22 17:33:33", "lastmod": "2023-10-18 21:48:05", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "McVay-R-C", "name": { "family": "McVay", "given": "Renee C." }, "orcid": "0000-0001-7766-5009" }, { "id": "Zhang-Xuan", "name": { "family": "Zhang", "given": "Xuan" } }, { "id": "Aumont-B", "name": { "family": "Aumont", "given": "Bernard" } }, { "id": "Valorso-R", "name": { "family": "Valorso", "given": "Richard" } }, { "id": "Camredon-M", "name": { "family": "Camredon", "given": "Marie" } }, { "id": "La-Yuyi-S", "name": { "family": "La", "given": "Yuyi S." } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Seinfeld-J-H", "name": { "family": "Seinfeld", "given": "John H." }, "orcid": "0000-0003-1344-4068" } ] }, "title": "SOA formation from the photooxidation of \u03b1-pinene: systematic exploration of the simulation of chamber data", "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: 2 November 2015 \u2013 Published in Atmos. Chem. Phys. Discuss.: 25 November 2015. Revised: 17 February 2016 \u2013 Accepted: 23 February 2016 \u2013 Published: 4 March 2016. \n\nThis work was supported by National Science Foundation grant AGS-1523500. Renee C. McVay acknowledges support by a National Science Foundation Graduate Research Fellowship under grant no. DGE-1144469. Bernard Aumont acknowledges support from the French National Research Agency (ANR) under the MAGNIFY project (ANR-14-CE01-0010).\n\nPublished - acp-16-2785-2016.pdf
Supplemental Material - acp-16-2785-2016-supplement.pdf
", "abstract": "Chemical mechanisms play an important role in simulating the atmospheric chemistry of volatile organic compound oxidation. Comparison of mechanism simulations with laboratory chamber data tests our level of understanding of the prevailing chemistry as well as the dynamic processes occurring in the chamber itself. \u03b1-Pinene photooxidation is a well-studied system experimentally, for which detailed chemical mechanisms have been formulated. Here, we present the results of simulating low-NO \u03b1-pinene photooxidation experiments conducted in the Caltech chamber with the Generator for Explicit Chemistry and Kinetics of Organics in the Atmosphere (GECKO-A) under varying concentrations of seed particles and OH levels. Unexpectedly, experiments conducted at low and high OH levels yield the same secondary organic aerosol (SOA) growth, whereas GECKO-A predicts greater SOA growth under high OH levels. SOA formation in the chamber is a result of a competition among the rates of gas-phase oxidation to low-volatility products, wall deposition of these products, and condensation into the aerosol phase. Various processes \u2013 such as photolysis of condensed-phase products, particle-phase dimerization, and peroxy radical autoxidation \u2013 are explored to rationalize the observations. In order to explain the observed similar SOA growth at different OH levels, we conclude that vapor wall loss in the Caltech chamber is likely of order 10^(\u22125)\u202fs^(\u22121), consistent with previous experimental measurements in that chamber. We find that GECKO-A tends to overpredict the contribution to SOA of later-generation oxidation products under high-OH conditions. Moreover, we propose that autoxidation may alternatively resolve some or all of the measurement\u2013model discrepancy, but this hypothesis cannot be confirmed until more explicit mechanisms are established for \u03b1-pinene autoxidation. The key role of the interplay among oxidation rate, product volatility, and vapor\u2013wall deposition in chamber experiments is illustrated.", "date": "2016-03-04", "date_type": "published", "publication": "Atmospheric Chemistry and Physics", "volume": "16", "number": "5", "publisher": "European Geosciences Union", "pagerange": "2785-2802", "id_number": "CaltechAUTHORS:20160610-123722476", "issn": "1680-7324", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160610-123722476", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "AGS-1523500" }, { "agency": "NSF Graduate Research Fellowship", "grant_number": "DGE-1144469" }, { "agency": "Agence Nationale pour la Recherche (ANR)", "grant_number": "ANR-14-CE01-0010" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/acp-16-2785-2016", "primary_object": { "basename": "acp-16-2785-2016-supplement.pdf", "url": "https://authors.library.caltech.edu/records/f0g3b-f1643/files/acp-16-2785-2016-supplement.pdf" }, "related_objects": [ { "basename": "acp-16-2785-2016.pdf", "url": "https://authors.library.caltech.edu/records/f0g3b-f1643/files/acp-16-2785-2016.pdf" } ], "resource_type": "article", "pub_year": "2016", "author_list": "McVay, Renee C.; Zhang, Xuan; et el." }, { "id": "https://authors.library.caltech.edu/records/6s6st-ws314", "eprint_id": 67586, "eprint_status": "archive", "datestamp": "2023-08-22 17:30:17", "lastmod": "2023-10-18 21:18:34", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Cai-Chenxia", "name": { "family": "Cai", "given": "Chenxia" } }, { "id": "Kulkarni-Sarika", "name": { "family": "Kulkarni", "given": "Sarika" } }, { "id": "Zhao-Zhan", "name": { "family": "Zhao", "given": "Zhan" } }, { "id": "Kaduwela-A-P", "name": { "family": "Kaduwela", "given": "Ajith P." } }, { "id": "Avise-J-C", "name": { "family": "Avise", "given": "Jeremy C." } }, { "id": "DaMassa-J-A", "name": { "family": "DaMassa", "given": "John A." } }, { "id": "Singh-H-B", "name": { "family": "Singh", "given": "Hanwant B." } }, { "id": "Weinheimer-A-J", "name": { "family": "Weinheimer", "given": "Andrew J." }, "orcid": "0000-0001-6175-8286" }, { "id": "Cohen-R-C", "name": { "family": "Cohen", "given": "Ronald C." }, "orcid": "0000-0001-6617-7691" }, { "id": "Diskin-G-S", "name": { "family": "Diskin", "given": "Glenn S." }, "orcid": "0000-0002-3617-0269" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul" }, "orcid": "0000-0002-6126-3854" }, { "id": "Dibb-J-E", "name": { "family": "Dibb", "given": "Jack E." }, "orcid": "0000-0003-3096-7709" }, { "id": "Huey-G", "name": { "family": "Huey", "given": "Greg" } }, { "id": "Wisthaler-A", "name": { "family": "Wisthaler", "given": "Armin" } }, { "id": "Jimenez-J-L", "name": { "family": "Jimenez", "given": "Jose L." }, "orcid": "0000-0001-6203-1847" }, { "id": "Cubison-M-J", "name": { "family": "Cubison", "given": "Michael J." } } ] }, "title": "Simulating reactive nitrogen, carbon monoxide, and ozone in California during ARCTAS-CARB 2008 with high wildfire activity", "ispublished": "pub", "full_text_status": "public", "keywords": "Ozone; Carbon monoxide; Reactive nitrogen; San Joaquin valley; South coast air basin; Wildfires", "note": "\u00a9 2016 Elsevier. \n\nReceived 8 September 2015, Revised 8 December 2015, Accepted 9 December 2015, Available online 24 December 2015. \n\nThe ARCTAS-CARB campaign was funded by the NASA Tropospheric Chemistry Program, the NASA Radiation Sciences Program, and the California Air Resources Board. CH3CN measurements were supported by the Austrian Federal Ministry for Transport, Innovation and Technology through the Austrian Space Applications Programme of the Austrian Research Promotion Agency. Tomas Mikoviny is acknowledged for his contribution in the CH3CN data analysis. We thank all ARCTAS-CARB participants for their support and contributions. Vernon Hughes at CARB provided us with the emissions inventories used in this study. We also thank Eileen McCauley, Dazhong Yin, Bruce Jackson, Jin Lu, Adam Gerber and Klaus Scott of CARB for valuable discussions.\n\nSupplemental Material - mmc1.pdf
", "abstract": "Predictions of O_3, CO, total NO_y and individual NO_y species (NO, NO_2, HNO_3, PAN, alkyl nitrates and aerosol nitrate) from a fine resolution regional air quality modeling system for the South Coast Air Basin (SoCAB) and San Joaquin Valley Air Basin (SJVAB) of California are presented and evaluated for the 2008 ARCTAS-CARB campaign. The measurements of the chemical compounds from the fire plumes during the field campaign allow for the evaluation of the model's ability to simulate fire-influenced air masses as well. In general, the model successfully simulated the broad spatial distribution of chemical compounds in both air basins as well as the variation within the basins. Using inventories that reflect 2008 emissions levels, the model performed well in simulating NO_x (NO + NO_2) in SoCAB. Therefore, the under prediction of O_3 over these areas is more likely caused by uncertainties with the VOC emissions, chemistry, or discrepancies in the meteorology. The model did not capture the relatively high levels of O_3, and some reactive nitrogen species that were measured off shore of the SoCAB, indicating potential missing sources or the transport from on shore to off shore was not successfully captured. In SJVAB, the model had good performance in simulating different chemical compounds in the Fresno and Arvin areas. However, enhanced concentrations of O_3, NO_x, HNO_3 and PAN near dairy farms were significantly underestimated in the model. Negative biases also exist for O_3 and HNO_3 near oil fields, suggesting larger uncertainties associated with these emission sources. While the model simulated the total NO_y mixing ratios reasonably well, the prediction for partitioning between individual compounds showed larger uncertainties in the model simulation. Although the fire emissions inventory was updated to include the latest emissions estimates and speciation profiles, our model shows limited improvement in simulating the enhancement of O_3, CO, and PAN under fire impact as compared to a previous version of the modeling system. Further improvements in simulating fire emissions, especially the timing and the plume injection heights, are desired in order to better simulate the impact of fires.", "date": "2016-03", "date_type": "published", "publication": "Atmospheric Environment", "volume": "128", "publisher": "Elsevier", "pagerange": "28-44", "id_number": "CaltechAUTHORS:20160602-143956377", "issn": "1352-2310", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160602-143956377", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA" }, { "agency": "California Air Resources Board" }, { "agency": "Bundesministerium f\u00fcr Verkehr, Innovation und Technologie (BMVIT)" }, { "agency": "Austrian Research Promotion Agency (FFG)" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/j.atmosenv.2015.12.031", "primary_object": { "basename": "mmc1.pdf", "url": "https://authors.library.caltech.edu/records/6s6st-ws314/files/mmc1.pdf" }, "resource_type": "article", "pub_year": "2016", "author_list": "Cai, Chenxia; Kulkarni, Sarika; et el." }, { "id": "https://authors.library.caltech.edu/records/f07hx-pwn42", "eprint_id": 103555, "eprint_status": "archive", "datestamp": "2023-08-22 17:26:40", "lastmod": "2023-10-20 16:29:26", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Kulawik-S-S", "name": { "family": "Kulawik", "given": "Susan" } }, { "id": "Wunch-D", "name": { "family": "Wunch", "given": "Debra" }, "orcid": "0000-0002-4924-0377" }, { "name": { "family": "O'Dell", "given": "Christopher" } }, { "id": "Frankenberg-C", "name": { "family": "Frankenberg", "given": "Christian" }, "orcid": "0000-0002-0546-5857" }, { "name": { "family": "Reuter", "given": "Maximilian" }, "orcid": "0000-0001-9141-3895" }, { "name": { "family": "Oda", "given": "Tomohiro" } }, { "name": { "family": "Chevallier", "given": "Frederic" }, "orcid": "0000-0002-4327-3813" }, { "name": { "family": "Sherlock", "given": "Vanessa" } }, { "name": { "family": "Buchwitz", "given": "Michael" }, "orcid": "0000-0001-7616-1837" }, { "id": "Osterman-G-B", "name": { "family": "Osterman", "given": "Greg" } }, { "id": "Miller-C-E", "name": { "family": "Miller", "given": "Charles E." }, "orcid": "0000-0002-9380-4838" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" }, { "name": { "family": "Griffith", "given": "David" }, "orcid": "0000-0002-7986-1924" }, { "name": { "family": "Morino", "given": "Isamu" }, "orcid": "0000-0003-2720-1569" }, { "name": { "family": "Dubey", "given": "Manvendra K." }, "orcid": "0000-0002-3492-790X" }, { "name": { "family": "Deutscher", "given": "Nicholas M." } }, { "name": { "family": "Notholt", "given": "Justus" } }, { "name": { "family": "Hase", "given": "Frank" } }, { "name": { "family": "Warneke", "given": "Thorsten" } }, { "name": { "family": "Sussmann", "given": "Ralf" } }, { "name": { "family": "Robinson", "given": "John" } }, { "name": { "family": "Strong", "given": "Kimberly" }, "orcid": "0000-0001-9947-1053" }, { "name": { "family": "Schneider", "given": "Matthias" } }, { "name": { "family": "De\u00a0Mazi\u00e8re", "given": "Martine" } }, { "name": { "family": "Shiomi", "given": "Kei" } }, { "name": { "family": "Feist", "given": "Dietrich G." }, "orcid": "0000-0002-5890-6687" }, { "name": { "family": "Iraci", "given": "Laura T." } }, { "id": "Wolf-Joyce", "name": { "family": "Wolf", "given": "Joyce" } } ] }, "title": "Consistent evaluation of ACOS-GOSAT, BESD-SCIAMACHY, CarbonTracker, and MACC through comparisons to TCCON", "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: 19 May 2015 \u2013 Discussion started: 22 Jun 2015 \u2013 Revised: 24 Jan 2016 \u2013 Accepted: 29 Jan 2016 \u2013 Published: 29 Feb 2016. \n\nFunded by NASA Roses ESDR-ERR 10/10-ESDRERR10-0031, \"Estimation of biases and errors of CO\u2082 satellite observations from AIRS, GOSAT, SCIAMACHY, TES, and OCO-2\". \n\nMaximilian Reuter and Michael Buchwitz received funding from ESA (GHG-CCI project of ESA's Climate Change Initiative) and from the University and state of Bremen. \n\nInformation about all TCCON sites and their sources of funding can be found on the TCCON website (https://tccon-wiki.caltech.edu/). \n\nManvendra K. Dubey is grateful for the funding for monitoring at Four Corners by LANL-LDRD, 20110081DR. \n\nFr\u00e9d\u00e9ric Chevallier received funding from the EU H2020 Programme (grant agreement no. 630080, MACC III). NCEP Reanalysis data used in dynamic coincidence criteria were provided by the NOAA/OAR/ESRL PSD, Boulder, Colorado, USA, from their website at http://www.esrl.noaa.gov/psd/. Thanks to Andrew R. Jacobson for help with CarbonTracker. \n\nAuthor contributions. Susan Kulawik set the direction of the research and did much of the analysis. The following authors were involved with discussions of results with specific knowledge in the listed areas: Debra Wunch, TCCON, Christopher O'Dell, ACOS-GOSAT, Christian Frankenberg, ACOS-GOSAT, Maximilian Reuter, BESD-SCIAMACHY, Tomohiro Oda, CarbonTracker, Frederic Chevallier, MACC, Vanessa Sherlock, TCCON, Michael Buchwitz, BESD-SCIAMACHY, Greg Osterman, ACOS-GOSAT, Charles Miller, CO\u2082 data records. The TCCON data providers, who also provide expertise regarding TCCON sites are Paul Wennberg, David Griffith, Isamu Morino, Manvendra Dubey, Nicholas M. Deutscher, Justus Notholt, Frank Hase, Thorsten Warneke, Ralf Sussmann, John Robinson, Kimberly Strong, and Matthias Schneider. Joyce Wolf is a science programmer and provided technical expertise. \n\nEdited by: H. Worden.\n\nPublished - amt-9-683-2016.pdf
", "abstract": "Consistent validation of satellite CO\u2082 estimates is a prerequisite for using multiple satellite CO\u2082 measurements for joint flux inversion, and for establishing an accurate long-term atmospheric CO\u2082 data record. Harmonizing satellite CO\u2082 measurements is particularly important since the differences in instruments, observing geometries, sampling strategies, etc. imbue different measurement characteristics in the various satellite CO\u2082 data products. We focus on validating model and satellite observation attributes that impact flux estimates and CO\u2082 assimilation, including accurate error estimates, correlated and random errors, overall biases, biases by season and latitude, the impact of coincidence criteria, validation of seasonal cycle phase and amplitude, yearly growth, and daily variability. We evaluate dry-air mole fraction (X_(CO\u2082)) for Greenhouse gases Observing SATellite (GOSAT) (Atmospheric CO\u2082 Observations from Space, ACOS b3.5) and SCanning Imaging Absorption spectroMeter for Atmospheric CHartographY (SCIAMACHY) (Bremen Optimal Estimation DOAS, BESD v2.00.08) as well as the CarbonTracker (CT2013b) simulated CO\u2082 mole fraction fields and the Monitoring Atmospheric Composition and Climate (MACC) CO\u2082 inversion system (v13.1) and compare these to Total Carbon Column Observing Network (TCCON) observations (GGG2012/2014). We find standard deviations of 0.9, 0.9, 1.7, and 2.1 ppm vs. TCCON for CT2013b, MACC, GOSAT, and SCIAMACHY, respectively, with the single observation errors 1.9 and 0.9 times the predicted errors for GOSAT and SCIAMACHY, respectively. We quantify how satellite error drops with data averaging by interpreting according to error\u00b2 = a\u00b2 + b\u00b2/n (with n being the number of observations averaged, a the systematic (correlated) errors, and b the random (uncorrelated) errors). a and b are estimated by satellites, coincidence criteria, and hemisphere. Biases at individual stations have year-to-year variability of \u2009\u223c\u2009\u202f0.3 ppm, with biases larger than the TCCON-predicted bias uncertainty of 0.4 ppm at many stations. We find that GOSAT and CT2013b underpredict the seasonal cycle amplitude in the Northern Hemisphere (NH) between 46 and 53\u00b0 N, MACC overpredicts between 26 and 37\u00b0 N, and CT2013b underpredicts the seasonal cycle amplitude in the Southern Hemisphere (SH). The seasonal cycle phase indicates whether a data set or model lags another data set in time. We find that the GOSAT measurements improve the seasonal cycle phase substantially over the prior while SCIAMACHY measurements improve the phase significantly for just two of seven sites. The models reproduce the measured seasonal cycle phase well except for at Lauder_125HR (CT2013b) and Darwin (MACC). We compare the variability within 1 day between TCCON and models in JJA; there is correlation between 0.2 and 0.8 in the NH, with models showing 10\u201350 % the variability of TCCON at different stations and CT2013b showing more variability than MACC. This paper highlights findings that provide inputs to estimate flux errors in model assimilations, and places where models and satellites need further investigation, e.g., the SH for models and 45\u201367\u00b0 N for GOSAT and CT2013b.", "date": "2016-02-29", "date_type": "published", "publication": "Atmospheric Measurement Techniques", "volume": "9", "number": "2", "publisher": "European Geosciences Union", "pagerange": "683-709", "id_number": "CaltechAUTHORS:20200529-093433263", "issn": "1867-8548", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200529-093433263", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "ESDR-ERR 10/10-ESDRERR10-0031" }, { "agency": "European Space Agency (ESA)" }, { "agency": "State of Bremen" }, { "agency": "Los Alamos National Laboratory", "grant_number": "20110081DR" }, { "agency": "European Research Council (ERC)", "grant_number": "630080" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/amt-9-683-2016", "primary_object": { "basename": "amt-9-683-2016.pdf", "url": "https://authors.library.caltech.edu/records/f07hx-pwn42/files/amt-9-683-2016.pdf" }, "resource_type": "article", "pub_year": "2016", "author_list": "Kulawik, Susan; Wunch, Debra; et el." }, { "id": "https://authors.library.caltech.edu/records/ks2tr-da486", "eprint_id": 103513, "eprint_status": "archive", "datestamp": "2023-08-22 17:26:35", "lastmod": "2023-10-20 16:26:54", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Kiel-M", "name": { "family": "Kiel", "given": "M." }, "orcid": "0000-0002-9784-962X" }, { "id": "Wunch-D", "name": { "family": "Wunch", "given": "D." }, "orcid": "0000-0002-4924-0377" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Toon-G-C", "name": { "family": "Toon", "given": "G. C." }, "orcid": "0000-0003-4174-7541" }, { "id": "Hase-F", "name": { "family": "Hase", "given": "F." } }, { "id": "Blumenstock-T", "name": { "family": "Blumenstock", "given": "T." } } ] }, "title": "Improved retrieval of gas abundances from near-infrared solar FTIR spectra measured at the Karlsruhe TCCON station", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 Author(s) 2016. This work is distributed under\nthe Creative Commons Attribution 3.0 License. Published by Copernicus Publications on behalf of the European Geosciences Union. \n\nReceived: 16 Oct 2015 \u2013 Discussion started: 23 Nov 2015 \u2013 Revised: 19 Jan 2016 \u2013 Accepted: 16 Feb 2016 \u2013 Published: 29 Feb 2016. \n\nSpecial thanks are directed to the entire Caltech/JPL Team for making the author's stay at the California Institute of Technology possible. We would like to thank the KIT Graduate School for Climate and Environment (GRACE) for supporting this analysis. This work has been supported by the EU project NORS. We would like to thank NASA for support via grant NNX14AI60G. We acknowledge support by Deutsche Forschungsgemeinschaft and the Open Access Publishing Fund of the Karlsruhe Institute of Technology. \n\nThe article processing charges for this open-access publication were covered by a Research Centre of the Helmholtz Association. \n\nEdited by: I. Aben.\n\nPublished - amt-9-669-2016.pdf
", "abstract": "We present a modified retrieval strategy for solar absorption spectra recorded by the Karlsruhe Fourier Transform Infrared (FTIR) spectrometer, which is operational within the Total Carbon Column Observing Network (TCCON). In typical TCCON stations, the 3800\u201311\u202f000 cm\u207b\u00b9 spectral region is measured on a single extended Indium Gallium Arsenide (InGaAs) detector. The Karlsruhe setup instead splits the spectrum across an Indium Antimonide (InSb) and InGaAs detector through the use of a dichroic beam splitter. This permits measurements further into the mid-infrared (MIR) that are of scientific interest, but are not considered TCCON measurements. This optical setup induces, however, larger variations in the continuum level of the solar spectra than the typical TCCON setup. Here we investigate the appropriate treatment of continuum-level variations in the retrieval strategy using the spectra recorded in Karlsruhe. The broad spectral windows used by TCCON require special attention with respect to residual curvature in the spectral fits. To accommodate the unique setup of Karlsruhe, higher-order discrete Legendre polynomial basis functions have been enabled in the TCCON retrieval code to fit the continuum. This improves spectral fits and air-mass dependencies for affected spectral windows. After fitting the continuum curvature, the Karlsruhe greenhouse gas records are in good agreement with other European TCCON data sets.", "date": "2016-02-29", "date_type": "published", "publication": "Atmospheric Measurement Techniques", "volume": "9", "number": "2", "publisher": "European Geosciences Union", "pagerange": "669-682", "id_number": "CaltechAUTHORS:20200528-082840367", "issn": "1867-8548", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200528-082840367", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "European Union", "grant_number": "NORS" }, { "agency": "NASA", "grant_number": "NNX14AI60G" }, { "agency": "Deutsche Forschungsgemeinschaft (DFG)" }, { "agency": "Karlsruhe Institute of Technology" }, { "agency": "Helmholtz Association" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/amt-9-669-2016", "primary_object": { "basename": "amt-9-669-2016.pdf", "url": "https://authors.library.caltech.edu/records/ks2tr-da486/files/amt-9-669-2016.pdf" }, "resource_type": "article", "pub_year": "2016", "author_list": "Kiel, M.; Wunch, D.; et el." }, { "id": "https://authors.library.caltech.edu/records/p2qkq-rnc89", "eprint_id": 63921, "eprint_status": "archive", "datestamp": "2023-08-22 17:15:51", "lastmod": "2023-10-17 18:28:57", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "J\u00f8rgensen-S", "name": { "family": "J\u00f8rgensen", "given": "Solvejg" } }, { "id": "Knap-H-C", "name": { "family": "Knap", "given": "Hasse C." } }, { "id": "Otkj\u00e6r-R-V", "name": { "family": "Otkj\u00e6r", "given": "Rasmus V." }, "orcid": "0000-0002-6094-1828" }, { "id": "Jensen-A-M", "name": { "family": "Jensen", "given": "Annesofie M." } }, { "id": "Kjeldsen-M-L-H", "name": { "family": "Kjeldsen", "given": "Mette L. H." } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Kjaergaard-H-G", "name": { "family": "Kjaergaard", "given": "Henrik G." }, "orcid": "0000-0002-7275-8297" } ] }, "title": "Rapid Hydrogen Shift Scrambling in Hydroperoxy-Substituted Organic Peroxy Radicals", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2015 American Chemical Society. \n\nReceived: July 14, 2015; Revised: December 11, 2015; Published: December 15, 2015. \n\nWe are grateful to Theo Kurt\u00e9n for helpful discussions and to Kristian H. M\u00f8ller for running some of the calculations. We thank the Copenhagen Center for Exploitation of Solar Energy for time on their computer. We thank the Danish Council for Independent Research - Natural Sciences and the Danish Center for Scientific Computing (DCSC) for funding. This material is based upon work supported by the National Science Foundation under CHE-1508526. \n\nThe authors declare no competing financial interest.\n\nSupplemental Material - jp5b06768_si_001.pdf
", "abstract": "Using quantum mechanical calculations, we have investigated hydrogen shift (H-shift) reactions in peroxy radicals derived from the atmospheric oxidation of 1-pentene (CH_2\u2550CHCH_2CH_2CH_3) and its monosubstituted derivatives. We investigate the peroxy radicals, HOCH_2CH(OO)CR_1HCH_2CH_3, HOCH_2CH(OO)CH_2CR_1HCH_3, and HOCH_2CH(OO)CH_2CH_2CR_1H_2, where the substituent R_1 is an alcoholic (OH), a hydroperoxy (OOH), or a methoxy (OCH_3) group. For peroxy radicals with an OOH substituent, the H-shift reaction from the hydrogen atom on the OOH group to the OO group is extremely fast. We find that the rate constants of this type of H-shift reactions are greater than 10^3 s^(\u20131) for both the forward and the reverse reactions. It leads to the formation of two different radical isomers that react through different reaction mechanisms and yield different products. These very fast H-shift reactions are much faster than the reactions with NO and HO_2 under most atmospheric conditions and must be included in the atmospheric modeling of volatile organic compounds where hydroperoxy peroxy radicals are formed.", "date": "2016-01-21", "date_type": "published", "publication": "Journal of Physical Chemistry A", "volume": "120", "number": "2", "publisher": "American Chemical Society", "pagerange": "266-275", "id_number": "CaltechAUTHORS:20160125-090211778", "issn": "1089-5639", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160125-090211778", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Danish Council for Independent Research" }, { "agency": "NSF", "grant_number": "CHE-1508526" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1021/acs.jpca.5b06768", "primary_object": { "basename": "jp5b06768_si_001.pdf", "url": "https://authors.library.caltech.edu/records/p2qkq-rnc89/files/jp5b06768_si_001.pdf" }, "resource_type": "article", "pub_year": "2016", "author_list": "J\u00f8rgensen, Solvejg; Knap, Hasse C.; et el." }, { "id": "https://authors.library.caltech.edu/records/j66fk-evs29", "eprint_id": 63562, "eprint_status": "archive", "datestamp": "2023-08-22 17:13:35", "lastmod": "2023-10-17 15:19:35", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Bates-K-H", "name": { "family": "Bates", "given": "Kelvin H." }, "orcid": "0000-0001-7544-9580" }, { "id": "Nguyen-Tran-B", "name": { "family": "Nguyen", "given": "Tran B." } }, { "id": "Teng-Alex-P", "name": { "family": "Teng", "given": "Alex P." } }, { "id": "Crounse-J-D", "name": { "family": "Crounse", "given": "John D." }, "orcid": "0000-0001-5443-729X" }, { "id": "Kjaergaard-H-G", "name": { "family": "Kjaergaard", "given": "Henrik G." }, "orcid": "0000-0002-7275-8297" }, { "id": "Stoltz-B-M", "name": { "family": "Stoltz", "given": "Brian M." }, "orcid": "0000-0001-9837-1528" }, { "id": "Seinfeld-J-H", "name": { "family": "Seinfeld", "given": "John H." }, "orcid": "0000-0003-1344-4068" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "Production and Fate of C_4 Dihydroxycarbonyl Compounds from Isoprene Oxidation", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2015 American Chemical Society. \n\nReceived: October 21, 2015. Revised: December 13, 2015. Publication Date (Web): December 15, 2015. \n\nThis material is based upon work supported by the National Science Foundation Graduate Research Fellowship under Grant DGE-1144469. Additionally, the authors thank the NSF (AGS-1240604) and the Electric Power Research Institute for supporting this work. Development of the GC-ToF-CIMS is supported by an award from the NSF's Major Research Instrumentation Program (AGS-1428482). \n\nThe authors declare no competing financial interest.\n\nSupplemental Material - jp5b10335_si_001.pdf
", "abstract": "Isoprene epoxydiols (IEPOX) are formed in high yield as second-generation products of atmospheric isoprene oxidation in pristine (low-NO) environments. IEPOX has received significant attention for its ability to form secondary organic aerosol, but the fate of IEPOX in the gas phase, and those of its oxidation products, remains largely unexplored. In this study, three dihydroxycarbonyl compounds with molecular formula of C_4H_8O_3, putative products of IEPOX oxidation, are synthesized to determine their isomer-specific yields from IEPOX. We find that 3,4-dihydroxy-2-butanone (DHBO) comprises 43% and 36% of the products from cis- and trans-\u03b2-IEPOX, respectively, and is by far the most abundant C_4H_8O_3 dihydroxycarbonyl compound produced by this mechanism. OH is found to react with DHBO with a rate coefficient of 1.10 \u00d7 10^(\u201311) cm^3 molecule^(\u20131) s^(\u20131) at 297 K, forming two hydroxydicarbonyl compounds that share the molecular formula C_4H_6O_3 with unitary yield. The results of this study are compared with field observations and used to propose a multigenerational mechanism of IEPOX oxidation. Finally, global simulations using GEOS-Chem, a chemical transport model, show that the C_4H_8O_3 dihydroxycarbonyl compounds and their oxidation products are widespread in the atmosphere and estimate annual global production of C_4H_8O_3 dihydroxycarbonyls to be 54 Tg\u202fy^(\u20131), primarily as DHBO.", "date": "2016-01-14", "date_type": "published", "publication": "Journal of Physical Chemistry A", "volume": "120", "number": "1", "publisher": "American Chemical Society", "pagerange": "106-117", "id_number": "CaltechAUTHORS:20160112-074404722", "issn": "1089-5639", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160112-074404722", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF Graduate Research Fellowship", "grant_number": "DGE-1144469" }, { "agency": "NSF", "grant_number": "AGS-1240604" }, { "agency": "Electric Power Research Institute (EPRI)" }, { "agency": "NSF", "grant_number": "AGS-1428482" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1021/acs.jpca.5b10335", "primary_object": { "basename": "jp5b10335_si_001.pdf", "url": "https://authors.library.caltech.edu/records/j66fk-evs29/files/jp5b10335_si_001.pdf" }, "resource_type": "article", "pub_year": "2016", "author_list": "Bates, Kelvin H.; Nguyen, Tran B.; et el." }, { "id": "https://authors.library.caltech.edu/records/fxc9w-q6v96", "eprint_id": 63701, "eprint_status": "archive", "datestamp": "2023-08-20 09:25:41", "lastmod": "2023-10-23 15:29:07", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Ayres-B-R", "name": { "family": "Ayres", "given": "B. R." } }, { "id": "Allen-H-M", "name": { "family": "Allen", "given": "H. M." } }, { "id": "Draper-D-C", "name": { "family": "Draper", "given": "D. C." } }, { "id": "Brown-S-S", "name": { "family": "Brown", "given": "S. S." } }, { "id": "Wild-R-J", "name": { "family": "Wild", "given": "R. J." } }, { "id": "Jimenez-J-L", "name": { "family": "Jimenez", "given": "J. L." }, "orcid": "0000-0001-6203-1847" }, { "id": "Day-D-A", "name": { "family": "Day", "given": "D. A." }, "orcid": "0000-0003-3213-4233" }, { "id": "Campuzano-Jost-P", "name": { "family": "Campuzano-Jost", "given": "P." }, "orcid": "0000-0003-3930-010X" }, { "id": "Hu-Weiwei", "name": { "family": "Hu", "given": "W." } }, { "id": "de-Gouw-J-A", "name": { "family": "de Gouw", "given": "J." }, "orcid": "0000-0002-0385-1826" }, { "id": "Koss-A", "name": { "family": "Koss", "given": "A." } }, { "id": "Cohen-R-C", "name": { "family": "Cohen", "given": "R. C." }, "orcid": "0000-0001-6617-7691" }, { "id": "Duffey-K-C", "name": { "family": "Duffey", "given": "K. C." } }, { "id": "Romer-P-S", "name": { "family": "Romer", "given": "P." }, "orcid": "0000-0002-4983-743X" }, { "id": "Baumann-K", "name": { "family": "Baumann", "given": "K." } }, { "id": "Edgerton-E-S", "name": { "family": "Edgerton", "given": "E." } }, { "id": "Takahama-S", "name": { "family": "Takahama", "given": "S." } }, { "id": "Thornton-J-A", "name": { "family": "Thornton", "given": "J. A." }, "orcid": "0000-0002-5098-4867" }, { "id": "Lee-Byung-Ho", "name": { "family": "Lee", "given": "B. H." } }, { "id": "Lopez-Hilfiker-F-D", "name": { "family": "Lopez-Hilfiker", "given": "F. D." } }, { "id": "Mohr-C", "name": { "family": "Mohr", "given": "C." } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Nguyen-Tran-B", "name": { "family": "Nguyen", "given": "T. B." } }, { "id": "Teng-Alex-P", "name": { "family": "Teng", "given": "A." } }, { "id": "Goldstein-A-H", "name": { "family": "Goldstein", "given": "A. H." }, "orcid": "0000-0003-4014-4896" }, { "id": "Olson-K", "name": { "family": "Olson", "given": "K." } }, { "id": "Fry-J-L", "name": { "family": "Fry", "given": "J. L." } } ] }, "title": "Organic nitrate aerosol formation via NO_3 + biogenic volatile organic compounds in the southeastern United States", "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: 12 May 2015 \u2013 Published in Atmos. Chem. Phys. Discuss.: 16 Jun 2015. Revised: 26 Oct 2015 \u2013 Accepted: 14 Nov 2015 \u2013 Published: 03 Dec 2015. \n\nWe would like to acknowledge Anne Marie Carlton, Jim Moore and all of the colleagues that helped to set up this study. B. R. Ayres, H. M. Allen, D. C. Draper, and J. L. Fry gratefully acknowledge funding from the National Center for Environmental Research (NCER) STAR Program, EPA no. RD-83539901 and NOAA NA13OAR4310063. D. A. Day, P. Campuzano-Jost, and J. L. Jimenez thank NSF AGS-1243354 and NOAA NA13OAR4310063; R. C. Cohen thanks NSF AGS-1120076 and AGS-1352972.\n\nPublished - acp-15-13377-2015.pdf
Supplemental Material - acp-15-13377-2015-supplement.pdf
", "abstract": "Gas- and aerosol-phase measurements of oxidants, biogenic volatile organic compounds (BVOCs) and organic nitrates made during the Southern Oxidant and Aerosol Study (SOAS campaign, Summer 2013) in central Alabama show that a nitrate radical (NO_3) reaction with monoterpenes leads to significant secondary aerosol formation. Cumulative losses of NO_3 to terpenes are correlated with increase in gas- and aerosol-organic nitrate concentrations made during the campaign. Correlation of NO_3 radical consumption to organic nitrate aerosol formation as measured by aerosol mass spectrometry and thermal dissociation laser-induced fluorescence suggests a molar yield of aerosol-phase monoterpene nitrates of 23\u201344 %. Compounds observed via chemical ionization mass spectrometry (CIMS) are correlated to predicted nitrate loss to BVOCs and show C_(10)H_(17)NO_5, likely a hydroperoxy nitrate, is a major nitrate-oxidized terpene product being incorporated into aerosols. The comparable isoprene product C_5H_9NO_5 was observed to contribute less than 1 % of the total organic nitrate in the aerosol phase and correlations show that it is principally a gas-phase product from nitrate oxidation of isoprene. Organic nitrates comprise between 30 and 45 % of the NOy budget during SOAS. Inorganic nitrates were also monitored and showed that during incidents of increased coarse-mode mineral dust, HNO_3 uptake produced nitrate aerosol mass loading at a rate comparable to that of organic nitrate produced via NO_3 + BVOCs.", "date": "2015-12-03", "date_type": "published", "publication": "Atmospheric Chemistry and Physics", "volume": "15", "number": "23", "publisher": "European Geosciences Union", "pagerange": "13377-13392", "id_number": "CaltechAUTHORS:20160115-095029693", "issn": "1680-7324", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160115-095029693", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Environmental Protection Agency (EPA)", "grant_number": "RD-83539901" }, { "agency": "National Oceanic and Atmospheric Administration (NOAA)", "grant_number": "NA13OAR4310063" }, { "agency": "NSF", "grant_number": "AGS-1243354" }, { "agency": "NSF", "grant_number": "AGS-1120076" }, { "agency": "NSF", "grant_number": "AGS-1352972" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/acp-15-13377-2015", "primary_object": { "basename": "acp-15-13377-2015-supplement.pdf", "url": "https://authors.library.caltech.edu/records/fxc9w-q6v96/files/acp-15-13377-2015-supplement.pdf" }, "related_objects": [ { "basename": "acp-15-13377-2015.pdf", "url": "https://authors.library.caltech.edu/records/fxc9w-q6v96/files/acp-15-13377-2015.pdf" } ], "resource_type": "article", "pub_year": "2015", "author_list": "Ayres, B. R.; Allen, H. M.; et el." }, { "id": "https://authors.library.caltech.edu/records/7zczx-f2568", "eprint_id": 62232, "eprint_status": "archive", "datestamp": "2023-08-20 08:40:53", "lastmod": "2023-10-23 15:12:50", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Wolfe-G-M", "name": { "family": "Wolfe", "given": "G. M." }, "orcid": "0000-0001-6586-4043" }, { "id": "Crounse-J-D", "name": { "family": "Crounse", "given": "J. D." }, "orcid": "0000-0001-5443-729X" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "Quantifying sources and sinks of reactive gases in the lower atmosphere using airborne flux observations", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2015 American Geophysical Union. \n\nReceived 18 AUG 2015; Accepted 23 SEP 2015; Accepted article online 28 SEP 2015; Published online 10 OCT 2015. \n\nThis work was supported by grants from the NASA ROSES SEAC4RS\n(NNH10ZDA001N and NNX12AC06G) and ACCDAM (NNX14AP48G and NNX14AP46G) programs. T.B.N. acknowledges support from NSF PRF award AGS-1331360. Isoprene measurements were supported by the Austrian Federal Ministry for Transport, Innovation and Technology (bmvit) through the Austrian Space Applications Programme (ASAP) of the Austrian Research Promotion Agency (FFG). A.W. and T.M. received support from the Visiting Scientist Program at the National Institute of Aerospace (NIA). We thank the DC-8 pilots, crew, payload operators, and mission scientists for their hard work and for the opportunity to calibrate the meteorological measurements. We are also grateful to NASA ESPO for mission\nlogistics. We thank the Jimenez, Brock, and Anderson groups for use of aerosol data. We also thank L. Kaser, B. Yuan, S.-W. Kim, and J. Thornton for helpful discussions. All data used in this analysis are publicly available under the SEAC4RS DOI at 10.5067/Aircraft/SEAC4RS/Aerosol-TraceGas-Cloud.\n\nPublished - Wolfe_et_al-2015-Geophysical_Research_Letters.pdf
Supplemental Material - grl53549-sup-0001-supplementary.pdf
", "abstract": "Atmospheric composition is governed by the interplay of emissions, chemistry, deposition, and transport. Substantial questions surround each of these processes, especially in forested environments with strong biogenic emissions. Utilizing aircraft observations acquired over a forest in the southeast U.S., we calculate eddy covariance fluxes for a suite of reactive gases and apply the synergistic information derived from this analysis to quantify emission and deposition fluxes, oxidant concentrations, aerosol uptake coefficients, and other key parameters. Evaluation of results against state-of-the-science models and parameterizations provides insight into our current understanding of this system and frames future observational priorities. As a near-direct measurement of fundamental process rates, airborne fluxes offer a new tool to improve biogenic and anthropogenic emissions inventories, photochemical mechanisms, and deposition parameterizations.", "date": "2015-10-16", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "42", "number": "19", "publisher": "American Geophysical Union", "pagerange": "8231-8240", "id_number": "CaltechAUTHORS:20151119-102703667", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20151119-102703667", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NNH10ZDA001N" }, { "agency": "NASA", "grant_number": "NNX12AC06G" }, { "agency": "NASA", "grant_number": "NNX14AP48G" }, { "agency": "NASA", "grant_number": "NNX14AP46G" }, { "agency": "NSF", "grant_number": "AGS-1331360" }, { "agency": "Austrian Research Promotion Agency (FFG)" }, { "agency": "National Institute of Aerospace (NIA)" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1002/2015GL065839", "primary_object": { "basename": "Wolfe_et_al-2015-Geophysical_Research_Letters.pdf", "url": "https://authors.library.caltech.edu/records/7zczx-f2568/files/Wolfe_et_al-2015-Geophysical_Research_Letters.pdf" }, "related_objects": [ { "basename": "grl53549-sup-0001-supplementary.pdf", "url": "https://authors.library.caltech.edu/records/7zczx-f2568/files/grl53549-sup-0001-supplementary.pdf" } ], "resource_type": "article", "pub_year": "2015", "author_list": "Wolfe, G. M.; Crounse, J. D.; et el." }, { "id": "https://authors.library.caltech.edu/records/qfr6q-2wr88", "eprint_id": 61913, "eprint_status": "archive", "datestamp": "2023-08-22 16:39:02", "lastmod": "2023-10-25 16:03:39", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Xiong-Fulin", "name": { "family": "Xiong", "given": "F." } }, { "id": "Teng-Alex-P", "name": { "family": "Teng", "given": "A. P." } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Crounse-J-D", "name": { "family": "Crounse", "given": "J. D." }, "orcid": "0000-0001-5443-729X" }, { "id": "Nguyen-Tran-B", "name": { "family": "Nguyen", "given": "T. B." } } ] }, "title": "Observation of isoprene hydroxynitrates in the southeastern United States and implications for the fate of NO_x", "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: 3 June 2015 \u2013 Published in Atmos. Chem. Phys. Discuss.: 2 July 2015; Revised: 19 September 2015 \u2013 Accepted: 28 September 2015 \u2013 Published: 9 October 2015. \n\nWe thank the organizers of the SOAS study, especially Ann Marie Carlton. We appreciate help from Jozef Peeters at the University of Leuven in elucidating the uncertainties associated with the current LIM1 mechanism. We acknowledge funding from the National Science Foundation (NSF) grant 1228496 and US Environmental Protection Agency (EPA) STAR grant 83540901.\n\nPublished - acp-15-11257-2015.pdf
Supplemental Material - acp-15-11257-2015-supplement.pdf
", "abstract": "Isoprene hydroxynitrates (IN) are tracers of the photochemical oxidation of isoprene in high NO_x environments. Production and loss of IN have a significant influence on the NO_x cycle and tropospheric O_3 chemistry. To better understand IN chemistry, a series of photochemical reaction chamber experiments was conducted to determine the IN yield from isoprene photooxidation at high NO concentrations (> 100 ppt). By combining experimental data and calculated isomer distributions, a total IN yield of 9(+4/\u22123) % was derived. The result was applied in a zero-dimensional model to simulate production and loss of ambient IN observed in a temperate forest atmosphere, during the Southern Oxidant and Aerosol Study (SOAS) field campaign, from 27 May to 11 July 2013. The 9 % yield was consistent with the observed IN/(MVK+MACR) ratios observed during SOAS. By comparing field observations with model simulations, we identified NO as the limiting factor for ambient IN production during SOAS, but vertical mixing at dawn might also contribute (~ 27 %) to IN dynamics. A close examination of isoprene's oxidation products indicates that its oxidation transitioned from a high-NO dominant chemical regime in the morning into a low-NO dominant regime in the afternoon. A significant amount of IN produced in the morning high NO regime could be oxidized in the low NO regime, and a possible reaction scheme was proposed.", "date": "2015-10-09", "date_type": "published", "publication": "Atmospheric Chemistry and Physics", "volume": "15", "number": "19", "publisher": "European Geosciences Union", "pagerange": "11257-11272", "id_number": "CaltechAUTHORS:20151105-155059904", "issn": "1680-7316", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20151105-155059904", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "PLR-1228496" }, { "agency": "Environmental Protection Agency (EPA)", "grant_number": "83540901" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/acp-15-11257-2015", "primary_object": { "basename": "acp-15-11257-2015-supplement.pdf", "url": "https://authors.library.caltech.edu/records/qfr6q-2wr88/files/acp-15-11257-2015-supplement.pdf" }, "related_objects": [ { "basename": "acp-15-11257-2015.pdf", "url": "https://authors.library.caltech.edu/records/qfr6q-2wr88/files/acp-15-11257-2015.pdf" } ], "resource_type": "article", "pub_year": "2015", "author_list": "Xiong, F.; Teng, A. P.; et el." }, { "id": "https://authors.library.caltech.edu/records/vg2kz-a8k50", "eprint_id": 60558, "eprint_status": "archive", "datestamp": "2023-08-22 16:38:17", "lastmod": "2023-10-24 16:39:52", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Schwantes-R-H", "name": { "family": "Schwantes", "given": "Rebecca H." }, "orcid": "0000-0002-7095-3718" }, { "id": "Teng-Alexander-P", "name": { "family": "Teng", "given": "Alexander P." }, "orcid": "0000-0002-6434-0501" }, { "id": "Nguyen-Tran-B", "name": { "family": "Nguyen", "given": "Tran B." } }, { "id": "Coggon-M-M", "name": { "family": "Coggon", "given": "Matthew M." }, "orcid": "0000-0002-5763-1925" }, { "id": "Crounse-J-D", "name": { "family": "Crounse", "given": "John D." }, "orcid": "0000-0001-5443-729X" }, { "id": "St-Clair-J-M", "name": { "family": "St. Clair", "given": "Jason M." }, "orcid": "0000-0002-9367-5749" }, { "id": "Zhang-Xuan", "name": { "family": "Zhang", "given": "Xuan" } }, { "id": "Schilling-K-A", "name": { "family": "Schilling", "given": "Katherine A." } }, { "id": "Seinfeld-J-H", "name": { "family": "Seinfeld", "given": "John H." }, "orcid": "0000-0003-1344-4068" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "Isoprene NO_3 Oxidation Products from the RO_2 + HO_2 Pathway", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2015 American Chemical Society.\n\nReceived: July 2, 2015; Revised: August 27, 2015; Publication Date (Web): September 3, 2015. \n\nThe authors thank the National Science Foundation (AGS-1240604) and the Electric Power Research Institute for their support of this work. TBN acknowledges support from NSF PRF award AGS-1331360. Development of the GC-ToF-CIMS is supported by an award from the National Science Foundation's Major Research Instrumentation Program (AGS-1428482). \n\nThe authors declare no competing financial interest.\n\nSupplemental Material - jp5b06355_si_001.pdf
", "abstract": "We describe the products of the reaction of the hydroperoxy radical (HO_2) with the alkylperoxy radical formed following addition of the nitrate radical (NO_3) and O_2 to isoprene. NO_3 adds preferentially to the C_1 position of isoprene (>6 times more favorably than addition to C_4), followed by the addition of O_2 to produce a suite of nitrooxy alkylperoxy radicals (RO_2). At an RO_2 lifetime of \u223c30 s, \u03b4-nitrooxy and \u03b2-nitrooxy alkylperoxy radicals are present in similar amounts. Gas-phase product yields from the RO_2 + HO_2 pathway are identified as 0.75\u20130.78 isoprene nitrooxy hydroperoxide (INP), 0.22 methyl vinyl ketone (MVK) + formaldehyde (CH_2O) + hydroxyl radical (OH) + nitrogen dioxide (NO_2), and 0\u20130.03 methacrolein (MACR) + CH_2O + OH + NO_2. We further examined the photochemistry of INP and identified propanone nitrate (PROPNN) and isoprene nitrooxy hydroxyepoxide (INHE) as the main products. INHE undergoes similar heterogeneous chemistry as isoprene dihydroxy epoxide (IEPOX), likely contributing to atmospheric secondary organic aerosol formation.", "date": "2015-10-08", "date_type": "published", "publication": "Journal of Physical Chemistry A", "volume": "119", "number": "40", "publisher": "American Chemical Society", "pagerange": "10158-10171", "id_number": "CaltechAUTHORS:20150928-082640803", "issn": "1089-5639", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150928-082640803", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "AGS-1240604" }, { "agency": "Electric Power Research Institute (EPRI)" }, { "agency": "NSF", "grant_number": "AGS-1331360" }, { "agency": "NSF", "grant_number": "AGS-1428482" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1021/acs.jpca.5b06355", "primary_object": { "basename": "jp5b06355_si_001.pdf", "url": "https://authors.library.caltech.edu/records/vg2kz-a8k50/files/jp5b06355_si_001.pdf" }, "resource_type": "article", "pub_year": "2015", "author_list": "Schwantes, Rebecca H.; Teng, Alexander P.; et el." }, { "id": "https://authors.library.caltech.edu/records/2p8gt-ayc46", "eprint_id": 61742, "eprint_status": "archive", "datestamp": "2023-08-22 16:23:50", "lastmod": "2023-10-25 15:41:55", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Kim-Patrick-S", "name": { "family": "Kim", "given": "P. S." } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Crounse-J-D", "name": { "family": "Crounse", "given": "J. D." }, "orcid": "0000-0001-5443-729X" }, { "id": "St-Clair-J-M", "name": { "family": "St. Clair", "given": "J. M." }, "orcid": "0000-0002-9367-5749" }, { "id": "Teng-Alex-P", "name": { "family": "Teng", "given": "A. P." } } ] }, "title": "Sources, seasonality, and trends of southeast US aerosol: an integrated analysis of surface, aircraft, and satellite observations with the GEOS-Chem chemical transport model", "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: 05 May 2015. Published in Atmos. Chem. Phys. Discuss.: 01 Jul 2015. Revised: 03 Sep 2015. Accepted: 05 Sep 2015. Published: 23 Sep 2015. \n\nWe are grateful to the entire NASA SEAC^4RS team for their help in the field. We thank Aaron van Donkelaar, Eloise Marais, Loretta Mickley, Randall Martin, Chuck Brock, Ann Dillner, Ralph Kahn, Armin Sorooshian, Tran Nguyen, and\nJenny Hand for helpful discussions and Sajeev Philip for assistance with downloading meteorological fields. We also thank Jack Dibb, Bruce Anderson and the LARGE team, Phil Russell, Jens Redemann and the 4STAR team, and Greg Huey for the data shown in the Supplement. This work was funded by the NASA Tropospheric Chemistry Program and by a Department of Energy Office of Science Graduate Fellowship to PSK made possible in part by the American Recovery and Reinvestment Act of 2009, administered by ORISE-ORAU under contract no. DE-AC05-06OR23100. P. Campuzano-Jost and J. L. Jimenez were supported by NASA NNX12AC03G and NSF GS-1243354/1360834. K. D. Froyd and J. Liao are supported by NASA grant NNH12AT29I from the Upper Atmosphere Research Program, Radiation Sciences Program, and Tropospheric Chemistry Program, and by NOAA base funding. D. B. Millet acknowledges support from NSF (Grant #1148951). P. O. Wennberg, J. D. Crounse, J. M. St. Clair, and A. P. Teng acknowledge support from NASA (NNX12AC06G and NNX14AP46G). We thank the US EPA for providing the 2010 North American emission inventory. The inventory is intended for research purposes and was developed for Phase 2 of the Air Quality Model Evaluation International Initiative (AQMEII) using information from the 2008-based modeling platform as a starting point. A technical document describing the 2008-based 2007v5 modeling platform can be found at http://epa.gov/ttn/chief/emch/2007v5/2007v5_2020base_EmisMod_TSD_13dec2012.pdf. A report on the 2008 NEI can be found at www.epa.gov/ttn/chief/net/2008report.pdf. GEOS-Chem is managed by the Harvard University Atmospheric Chemistry Modeling Group with support from the NASA Atmospheric Composition Modeling and Analysis Program. The GEOS-FP data used in this study were provided by the Global Modeling and Assimilation Office (GMAO) at NASA Goddard Space Flight Center. Edited by: K. Tsigaridis\n\nPublished - acp-15-10411-2015.pdf
", "abstract": "We use an ensemble of surface (EPA CSN, IMPROVE, SEARCH, AERONET), aircraft (SEAC4RS), and satellite (MODIS, MISR) observations over the southeast US during the summer\u2013fall of 2013 to better understand aerosol sources in the region and the relationship between surface particulate matter (PM) and aerosol optical depth (AOD). The GEOS-Chem global chemical transport model (CTM) with 25 \u00d7 25 km^2 resolution over North America is used as a common platform to interpret measurements of different aerosol variables made at different times and locations. Sulfate and organic aerosol (OA) are the main contributors to surface PM_(2.5) (mass concentration of PM finer than 2.5 \u03bcm aerodynamic diameter) and AOD over the southeast US. OA is simulated successfully with a simple parameterization, assuming irreversible uptake of low-volatility products of hydrocarbon oxidation. Biogenic isoprene and monoterpenes account for 60 % of OA, anthropogenic sources for 30 %, and open fires for 10 %. 60 % of total aerosol mass is in the mixed layer below 1.5 km, 25 % in the cloud convective layer at 1.5\u20133 km, and 15 % in the free troposphere above 3 km. This vertical profile is well captured by GEOS-Chem, arguing against a high-altitude source of OA. The extent of sulfate neutralization (f = [NH_4^+]/(2[SO_4^(2\u2212)] + [NO_3^\u2212]) is only 0.5\u20130.7 mol mol^(\u22121) in the observations, despite an excess of ammonia present, which could reflect suppression of ammonia uptake by OA. This would explain the long-term decline of ammonium aerosol in the southeast US, paralleling that of sulfate. The vertical profile of aerosol extinction over the southeast US follows closely that of aerosol mass. GEOS-Chem reproduces observed total column aerosol mass over the southeast US within 6 %, column aerosol extinction within 16 %, and space-based AOD within 8\u201328 % (consistently biased low). The large AOD decline observed from summer to winter is driven by sharp declines in both sulfate and OA from August to October. These declines are due to shutdowns in both biogenic emissions and UV-driven photochemistry. Surface PM_(2.5) shows far less summer-to-winter decrease than AOD and we attribute this in part to the offsetting effect of weaker boundary layer ventilation. The SEAC4RS aircraft data demonstrate that AODs measured from space are consistent with surface PM_(2.5). This implies that satellites can be used reliably to infer surface PM_(2.5) over monthly timescales if a good CTM representation of the aerosol vertical profile is available.", "date": "2015-09-23", "date_type": "published", "publication": "Atmospheric Chemistry and Physics", "volume": "15", "number": "18", "publisher": "European Geosciences Union", "pagerange": "10411-10433", "id_number": "CaltechAUTHORS:20151030-125811540", "issn": "1680-7324", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20151030-125811540", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC05-06OR23100" }, { "agency": "NASA", "grant_number": "NNX12AC03G" }, { "agency": "NSF", "grant_number": "GS-1243354" }, { "agency": "NSF", "grant_number": "AGS-1360834" }, { "agency": "NASA", "grant_number": "NNH12AT29I" }, { "agency": "National Oceanic and Atmospheric Administration (NOAA)" }, { "agency": "NSF", "grant_number": "AGS-1148951" }, { "agency": "NASA", "grant_number": "NNX12AC06G" }, { "agency": "NASA", "grant_number": "NNX14AP46G" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/acp-15-10411-2015", "primary_object": { "basename": "acp-15-10411-2015.pdf", "url": "https://authors.library.caltech.edu/records/2p8gt-ayc46/files/acp-15-10411-2015.pdf" }, "resource_type": "article", "pub_year": "2015", "author_list": "Kim, P. S.; Wennberg, P. O.; et el." }, { "id": "https://authors.library.caltech.edu/records/1nq85-xtp77", "eprint_id": 60203, "eprint_status": "archive", "datestamp": "2023-08-22 16:18:10", "lastmod": "2023-10-24 15:26:14", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Krechmer-J-E", "name": { "family": "Krechmer", "given": "Jordan E." }, "orcid": "0000-0003-3642-0659" }, { "id": "Coggon-M-M", "name": { "family": "Coggon", "given": "Matthew M." }, "orcid": "0000-0002-5763-1925" }, { "id": "Nguyen-Tran-B", "name": { "family": "Nguyen", "given": "Tran B." } }, { "id": "Crounse-J-D", "name": { "family": "Crounse", "given": "John D." }, "orcid": "0000-0001-5443-729X" }, { "id": "St-Clair-J-M", "name": { "family": "St. Clair", "given": "Jason M." }, "orcid": "0000-0002-9367-5749" }, { "id": "Zhang-Xuan", "name": { "family": "Zhang", "given": "Xuan" } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Seinfeld-J-H", "name": { "family": "Seinfeld", "given": "John H." }, "orcid": "0000-0003-1344-4068" } ] }, "title": "Formation of Low Volatility Organic Compounds and Secondary Organic Aerosol from Isoprene Hydroxyhydroperoxide Low-NO Oxidation", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2015 American Chemical Society.\n\nReceived: April 23, 2015; Revised: July 17, 2015; Accepted: July 24, 2015; Published: July 24, 2015. \n\nThis work was supported by grants NSF AGS-1243354, 1243356, 1247421, and 1246918, NOAA NA13OAR4310063, and DOE (BER/ASR) DE-SC0011105. J.K. is grateful for fellowships from CIRES, CU Graduate School, and EPA STAR (FP-91770901-0). We are grateful to the many contributions to the FIXCIT study made by the staff and students of the Wennberg and Seinfeld groups, and fellow participants. We also thank Profs. P. Ziemann and B. Aumount for useful discussions.\n\nSupplemental Material - es5b02031_si_001.pdf
", "abstract": "Gas-phase low volatility organic compounds (LVOC), produced from oxidation of isoprene 4-hydroxy-3-hydroperoxide (4,3-ISOPOOH) under low-NO conditions, were observed during the FIXCIT chamber study. Decreases in LVOC directly correspond to appearance and growth in secondary organic aerosol (SOA) of consistent elemental composition, indicating that LVOC condense (at OA below 1 \u03bcg m^(\u20133)). This represents the first simultaneous measurement of condensing low volatility species from isoprene oxidation in both the gas and particle phases. The SOA formation in this study is separate from previously described isoprene epoxydiol (IEPOX) uptake. Assigning all condensing LVOC signals to 4,3-ISOPOOH oxidation in the chamber study implies a wall-loss corrected non-IEPOX SOA mass yield of \u223c4%. By contrast to monoterpene oxidation, in which extremely low volatility VOC (ELVOC) constitute the organic aerosol, in the isoprene system LVOC with saturation concentrations from 10^(\u20132) to 10 \u03bcg m^(\u20133) are the main constituents. These LVOC may be important for the growth of nanoparticles in environments with low OA concentrations. LVOC observed in the chamber were also observed in the atmosphere during SOAS-2013 in the Southeastern United States, with the expected diurnal cycle. This previously uncharacterized aerosol formation pathway could account for \u223c5.0 Tg yr^(\u20131) of SOA production, or 3.3% of global SOA.", "date": "2015-09-01", "date_type": "published", "publication": "Environmental Science and Technology", "volume": "49", "number": "17", "publisher": "American Chemical Society", "pagerange": "10330-10339", "id_number": "CaltechAUTHORS:20150911-144046678", "issn": "0013-936X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150911-144046678", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "AGS-1243354" }, { "agency": "NSF", "grant_number": "AGS-1243356" }, { "agency": "NSF", "grant_number": "AGS-1247421" }, { "agency": "NSF", "grant_number": "AGS-1246918" }, { "agency": "National Oceanic and Atmospheric Administration (NOAA)", "grant_number": "NA13OAR4310063" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0011105" }, { "agency": "Cooperative Institute for Research in Environmental Sciences (CIRES)" }, { "agency": "University of Colorado" }, { "agency": "Environmental Protection Agency (EPA)", "grant_number": "FP-91770901-0" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1021/acs.est.5b02031", "primary_object": { "basename": "es5b02031_si_001.pdf", "url": "https://authors.library.caltech.edu/records/1nq85-xtp77/files/es5b02031_si_001.pdf" }, "resource_type": "article", "pub_year": "2015", "author_list": "Krechmer, Jordan E.; Coggon, Matthew M.; et el." }, { "id": "https://authors.library.caltech.edu/records/taxak-xkk33", "eprint_id": 61214, "eprint_status": "archive", "datestamp": "2023-08-22 16:07:31", "lastmod": "2023-10-25 14:37:59", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Barth-M-C", "name": { "family": "Barth", "given": "Mary C." } }, { "id": "Crounse-J-D", "name": { "family": "Crounse", "given": "John" }, "orcid": "0000-0001-5443-729X" }, { "id": "St-Clair-J-M", "name": { "family": "St. Clair", "given": "Jason" }, "orcid": "0000-0002-9367-5749" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul" }, "orcid": "0000-0002-6126-3854" } ] }, "title": "The Deep Convective Clouds and Chemistry (DC3) Field Campaign", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2015 American Meteorological Society. \n\nFinal Form: November 5, 2014. \n\nDC3 was a complex field campaign coordinating aircraft facilities and ground-based facilities at three different locations. There are many people to thank, each responsible for making the campaign successful. Specifically, we thank the DC-8 HDSP2 team\u2014Rushan Gao, Joshua Schwarz, Anne Perring, John Holloway, and Milos Markowic\u2014for the black carbon data used for the PM1 calculation. The National Science Foundation (NSF), the National Aeronautics and Space Administration (NASA), the Deutsches Zentrum f\u00fcr Luft- und Raumfahrt (DLR), and the National Oceanic and Atmospheric Administration (NOAA) are gratefully acknowledged for sponsoring the DC3 field experiment. The field project support provided by NCAR/EOL staff, especially Vidal Salazar and Jim Moore, is greatly appreciated. Data from the field campaign can be found at the NCAR/EOL field projects catalog (www.eol.ucar.edu/projects/dc3/).\n\nPublished - bams-d-13-00290.1.pdf
", "abstract": "The Deep Convective Clouds and Chemistry (DC3) field experiment produced an exceptional dataset on thunderstorms, including their dynamical, physical, and electrical structures and their impact on the chemical composition of the troposphere. The field experiment gathered detailed information on the chemical composition of the inflow and outflow regions of midlatitude thunderstorms in northeast Colorado, west Texas to central Oklahoma, and northern Alabama. A unique aspect of the DC3 strategy was to locate and sample the convective outflow a day after active convection in order to measure the chemical transformations within the upper-tropospheric convective plume. These data are being analyzed to investigate transport and dynamics of the storms, scavenging of soluble trace gases and aerosols, production of nitrogen oxides by lightning, relationships between lightning flash rates and storm parameters, chemistry in the upper troposphere that is affected by the convection, and related source characterization of the three sampling regions. DC3 also documented biomass-burning plumes and the interactions of these plumes with deep convection.", "date": "2015-08", "date_type": "published", "publication": "Bulletin of the American Meteorological Society", "volume": "96", "number": "8", "publisher": "American Meteorological Society", "pagerange": "1281-1309", "id_number": "CaltechAUTHORS:20151016-130103982", "issn": "0003-0007", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20151016-130103982", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF" }, { "agency": "NASA" }, { "agency": "Deutsches Zentrum f\u00fcr Luft-und Raumfahrt (DLR)" }, { "agency": "National Oceanic and Atmospheric Administration (NOAA)" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1175/BAMS-D-13-00290.1", "primary_object": { "basename": "bams-d-13-00290.1.pdf", "url": "https://authors.library.caltech.edu/records/taxak-xkk33/files/bams-d-13-00290.1.pdf" }, "resource_type": "article", "pub_year": "2015", "author_list": "Barth, Mary C.; Crounse, John; et el." }, { "id": "https://authors.library.caltech.edu/records/q26qh-hbs30", "eprint_id": 58734, "eprint_status": "archive", "datestamp": "2023-08-20 07:21:54", "lastmod": "2023-10-23 19:40:28", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Nguyen-Tran-B", "name": { "family": "Nguyen", "given": "Tran B." }, "orcid": "0000-0001-9206-4359" }, { "id": "Bates-Kelvin-H", "name": { "family": "Bates", "given": "Kelvin H." }, "orcid": "0000-0001-7544-9580" }, { "id": "Crounse-John-D", "name": { "family": "Crounse", "given": "John D." }, "orcid": "0000-0001-5443-729X" }, { "id": "Schwantes-Rebecca-H", "name": { "family": "Schwantes", "given": "Rebecca H." }, "orcid": "0000-0002-7095-3718" }, { "id": "Zhang-Xuan", "name": { "family": "Zhang", "given": "Xuan" } }, { "id": "Kjaergaard-Henrik-G", "name": { "family": "Kjaergaard", "given": "Henrik G." }, "orcid": "0000-0002-7275-8297" }, { "id": "Surratt-Jason-D", "name": { "family": "Surratt", "given": "Jason D." }, "orcid": "0000-0002-6833-1450" }, { "id": "Lin-Peng", "name": { "family": "Lin", "given": "Peng" } }, { "id": "Laskin-Alexander", "name": { "family": "Laskin", "given": "Alexander" }, "orcid": "0000-0002-7836-8417" }, { "id": "Seinfeld-J-H", "name": { "family": "Seinfeld", "given": "John H." }, "orcid": "0000-0003-1344-4068" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "Mechanism of the hydroxyl radical oxidation of methacryloyl peroxynitrate (MPAN) and its pathway toward secondary organic aerosol formation in the atmosphere", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2015 the Owner Societies.\n\nReceived 6th April 2015; Accepted 11th June 2015.\n\nFirst published online 12 Jun 2015.\n\nWe acknowledge funding from the U.S. National Science Foundation (NSF) Division of Atmospheric and Geospace Sciences (AGS) grant AGS-1240604 and the U.S. Department of Energy (DOE) grant DE-SC0006626. TBN is supported by the NSF postdoctoral research fellowship (PRF) award AGS-1331360. We thank Dr. Dennis Fitz (UC Riverside) for assistance with the Fitz Aerometric NO2/APN instrument, Matthew Coggon (Caltech) for AMS data collection and processing, Dr. Nathan F. Dalleska (Caltech Global Environmental Center) for help with the HR-MS analysis software and for use of the pH probe, and Dr. Avram Gold and Dr. Zhenfa Zhang (University of North Carolina) for assistance in synthesizing MAE. The HPLC-UV/Vis-ESI/HRMS analysis was performed at the W. R. Wiley Environmental Molecular Sciences Laboratory (EMSL), a national scientific user facility sponsored by the DOE's Office of Biological and Environmental Research and located at PNNL. PNNL is operated for the DOE by Battelle Memorial Institute under contract #DE-AC06-76RL0 1830.\n\nPublished - c5cp02001h.pdf
Supplemental Material - c5cp02001h1.pdf
", "abstract": "Methacryloyl peroxynitrate (MPAN), the acyl peroxynitrate of methacrolein, has been suggested to be an important secondary organic aerosol (SOA) precursor from isoprene oxidation. Yet, the mechanism by which MPAN produces SOA through reaction with the hydroxyl radical (OH) is unclear. We systematically evaluate three proposed mechanisms in controlled chamber experiments and provide the first experimental support for the theoretically-predicted lactone formation pathway from the MPAN + OH reaction, producing hydroxymethyl-methyl-\u03b1-lactone (HMML). The decomposition of the MPAN\u2013OH adduct yields HMML + NO_3 ( 75%) and hydroxyacetone + CO + NO_3 ( 25%), out-competing its reaction with atmospheric oxygen. The production of other proposed SOA precursors, e.g., methacrylic acid epoxide (MAE), from MPAN and methacrolein are negligible (<2%). Furthermore, we show that the beta-alkenyl moiety of MPAN is critical for lactone formation. Alkyl radicals formed cold via H-abstraction by OH do not decompose to HMML, even if they are structurally identical to the MPAN\u2013OH adduct. The SOA formation from HMML, from polyaddition of the lactone to organic compounds at the particle interface or in the condensed phase, is close to unity under dry conditions. However, the SOA yield is sensitive to particle liquid water and solvated ions. In hydrated inorganic particles, HMML reacts primarily with H\u00ac_2O to produce the monomeric 2-methylglyceric acid (2MGA) or with aqueous sulfate and nitrate to produce the associated organosulfate and organonitrate, respectively. 2MGA, a tracer for isoprene SOA, is semivolatile and its accommodation in aerosol water decreases with decreasing pH. Conditions that enhance the production of neutral 2MGA suppress SOA mass from the HMML channel. Considering the liquid water content and pH ranges of ambient particles, 2MGA will exist largely as a gaseous compound in some parts of the atmosphere.", "date": "2015-07-21", "date_type": "published", "publication": "Physical Chemistry Chemical Physics", "volume": "17", "number": "27", "publisher": "Royal Society of Chemistry", "pagerange": "17914-17926", "id_number": "CaltechAUTHORS:20150701-104453949", "issn": "1463-9076", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150701-104453949", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "AGS-1240604" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0006626" }, { "agency": "NSF Postdoctoral Fellowship", "grant_number": "AGS-1331360" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC06-76RL0 1830" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1039/c5cp02001h", "primary_object": { "basename": "c5cp02001h.pdf", "url": "https://authors.library.caltech.edu/records/q26qh-hbs30/files/c5cp02001h.pdf" }, "related_objects": [ { "basename": "c5cp02001h1.pdf", "url": "https://authors.library.caltech.edu/records/q26qh-hbs30/files/c5cp02001h1.pdf" } ], "resource_type": "article", "pub_year": "2015", "author_list": "Nguyen, Tran B.; Bates, Kelvin H.; et el." }, { "id": "https://authors.library.caltech.edu/records/fk58r-p7x33", "eprint_id": 53569, "eprint_status": "archive", "datestamp": "2023-08-22 15:34:21", "lastmod": "2023-10-19 21:52:32", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Praske-E", "name": { "family": "Praske", "given": "Eric" }, "orcid": "0000-0001-7169-4423" }, { "id": "Crounse-J-D", "name": { "family": "Crounse", "given": "John D." }, "orcid": "0000-0001-5443-729X" }, { "id": "Bates-K-H", "name": { "family": "Bates", "given": "Kelvin H." }, "orcid": "0000-0001-7544-9580" }, { "id": "Kurt\u00e9n-T", "name": { "family": "Kurt\u00e9n", "given": "Theo" }, "orcid": "0000-0002-6416-4931" }, { "id": "Kjaergaard-H-G", "name": { "family": "Kjaergaard", "given": "Henrik G." }, "orcid": "0000-0002-7275-8297" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "Atmospheric Fate of Methyl Vinyl Ketone: Peroxy Radical Reactions with NO and HO_2", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2014 American Chemical Society. \n\nReceived: October 24, 2014; Revised: December 8, 2014; Publication Date (Web): December 8, 2014. \n\nThe authors thank NASA (NNX12AC06G) and NSF (AGS-1240604), the Danish Council for Independent Research-Natural Sciences, and the Danish Center for Scientific Computing (DCSC) for their support of this research. K.H.B. acknowledges support from an NSF Graduate Research Fellowship under Grant DGE-1144469. We thank Daniel Jacob and the Atmospheric Chemistry Modeling Group at Harvard University for making GEOS-Chem available for use in this study. The meteorological data used in the GEOS-Chem simulations have been provided by the Global Modeling and Assimilation Office (GMAO) at NASA Goddard Space Flight Center. Finally, we thank the reviewers for comments that improved this manuscript.\n\nSupplemental Material - jp5107058_si_001.pdf
", "abstract": "First generation product yields from the OH-initiated oxidation of methyl vinyl ketone (3-buten-2-one, MVK) under both low and high NO conditions are reported. In the low NO chemistry, three distinct reaction channels are identified leading to the formation of (1) OH, glycolaldehyde, and acetyl peroxy R2a, (2) a hydroperoxide R2b, and (3) an \u03b1-diketone R2c. The \u03b1-diketone likely results from HO_x-neutral chemistry previously only known to occur in reactions of HO_2 with halogenated peroxy radicals. Quantum chemical calculations demonstrate that all channels are kinetically accessible at 298 K. In the high NO chemistry, glycolaldehyde is produced with a yield of 74 \u00b1 6.0%. Two alkyl nitrates are formed with a combined yield of 4.0 \u00b1 0.6%. We revise a three-dimensional chemical transport model to assess what impact these modifications in the MVK mechanism have on simulations of atmospheric oxidative chemistry. The calculated OH mixing ratio over the Amazon increases by 6%, suggesting that the low NO chemistry makes a non-negligible contribution toward sustaining the atmospheric radical pool.", "date": "2015-05-14", "date_type": "published", "publication": "Journal of Physical Chemistry A", "volume": "119", "number": "19", "publisher": "American Chemical Society", "pagerange": "4562-4572", "id_number": "CaltechAUTHORS:20150112-110218438", "issn": "1089-5639", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150112-110218438", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NNX12AC06G" }, { "agency": "NSF", "grant_number": "AGS-1240604" }, { "agency": "Danish Council for Independent Research-Natural Sciences" }, { "agency": "Danish Center for Scientific Computing" }, { "agency": "NSF Graduate Research Fellowship", "grant_number": "DGE-1144469" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1021/jp5107058", "primary_object": { "basename": "jp5107058_si_001.pdf", "url": "https://authors.library.caltech.edu/records/fk58r-p7x33/files/jp5107058_si_001.pdf" }, "resource_type": "article", "pub_year": "2015", "author_list": "Praske, Eric; Crounse, John D.; et el." }, { "id": "https://authors.library.caltech.edu/records/cwt5e-1ek85", "eprint_id": 57965, "eprint_status": "archive", "datestamp": "2023-08-22 15:24:22", "lastmod": "2023-10-23 17:56:53", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Teng-Alex-P", "name": { "family": "Teng", "given": "A. P." } }, { "id": "Crounse-J-D", "name": { "family": "Crounse", "given": "J. D." }, "orcid": "0000-0001-5443-729X" }, { "id": "Lee-L", "name": { "family": "Lee", "given": "L." } }, { "id": "St-Clair-J-M", "name": { "family": "St. Clair", "given": "J. M." }, "orcid": "0000-0002-9367-5749" }, { "id": "Cohen-R-C", "name": { "family": "Cohen", "given": "R. C." }, "orcid": "0000-0001-6617-7691" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "Hydroxy nitrate production in the OH-initiated oxidation of alkenes", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 Author(s) 2015. CC Attribution 3.0 License. Published by Copernicus Publications on behalf of the European Geosciences Union.\n\nReceived: 10 February 2014 \u2013 Published in Atmos. Chem. Phys. Discuss.: 13 March 2014 - Revised: 13 March 2015 \u2013 Accepted: 25 March 2015 \u2013 Published: 28 April 2015. \n\nThe authors thank T. Ryerson, I. B. Pollack, and J. Peischl at NOAA ESRL for ozone observations and T. F. Hanisco and G. M. Wolfe at NASA for formaldehyde observations from the NASA SEAC4RS flight on 18 September 2013. We acknowledge grant funding from the National Science Foundation (NSF) under grant AGS-1240604 and funding from the National Aeronautics and Space Administration (NASA) under grant NNX12AC06G and NNX14AP46G-ACCDAM.\n\nPublished - acp-15-4297-2015.pdf
Supplemental Material - acp-15-4297-2015-supplement.pdf
", "abstract": "Alkenes are oxidized rapidly in the atmosphere by addition of OH and subsequently O_2 leading to the formation of \u03b2-hydroxy peroxy radicals. These peroxy radicals react with NO to form \u03b2-hydroxy nitrates with a branching ratio \u03b1. We quantify \u03b1 for C_2\u2013C_8 alkenes at 295 K \u00b1 3 and 993 hPa. The branching ratio can be expressed as \u03b1 = (0.045 \u00b1 0.016) \u00d7 N \u2212 (0.11 \u00b1 0.05) where N is the number of heavy atoms (excluding the peroxy moiety), and listed errors are 2\u03c3. These branching ratios are larger than previously reported and are similar to those for peroxy radicals formed from H abstraction from alkanes. We find the isomer distributions of \u03b2-hydroxy nitrates formed under NO-dominated peroxy radical chemistry to be different than the isomer distribution of hydroxy hydroperoxides produced under HO2-dominated peroxy radical chemistry. Assuming unity yield for the hydroperoxides implies that the branching ratio to form \u03b2-hydroxy nitrates increases with substitution of RO_2. Deuterium substitution enhances the branching ratio to form hydroxy nitrates in both propene and isoprene by a factor of ~ 1.5. The role of alkene chemistry in the Houston region is re-evaluated using the RONO_2 branching ratios reported here. Small alkenes are found to play a significant role in present-day oxidant formation more than a decade (2013) after the 2000 Texas Air Quality Study identified these compounds as major contributors to photochemical smog in Houston.", "date": "2015-04-28", "date_type": "published", "publication": "Atmospheric Chemistry and Physics", "volume": "15", "number": "8", "publisher": "European Geosciences Union", "pagerange": "4297-4316", "id_number": "CaltechAUTHORS:20150603-085800924", "issn": "1680-7316", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150603-085800924", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "AGS-1240604" }, { "agency": "NASA", "grant_number": "NNX12AC06G" }, { "agency": "NASA", "grant_number": "NNX14AP46G-ACCDAM" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/acp-15-4297-2015", "primary_object": { "basename": "acp-15-4297-2015-supplement.pdf", "url": "https://authors.library.caltech.edu/records/cwt5e-1ek85/files/acp-15-4297-2015-supplement.pdf" }, "related_objects": [ { "basename": "acp-15-4297-2015.pdf", "url": "https://authors.library.caltech.edu/records/cwt5e-1ek85/files/acp-15-4297-2015.pdf" } ], "resource_type": "article", "pub_year": "2015", "author_list": "Teng, A. P.; Crounse, J. D.; et el." }, { "id": "https://authors.library.caltech.edu/records/n7x56-y3m51", "eprint_id": 57791, "eprint_status": "archive", "datestamp": "2023-08-22 15:22:28", "lastmod": "2023-10-23 17:45:25", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Liao-Jin", "name": { "family": "Liao", "given": "Jin" } }, { "id": "Froyd-K-D", "name": { "family": "Froyd", "given": "Karl D." } }, { "id": "Murphy-D-M", "name": { "family": "Murphy", "given": "Daniel M." } }, { "id": "Keutsch-F-N", "name": { "family": "Keutsch", "given": "Frank N." } }, { "id": "Yu-Ge", "name": { "family": "Yu", "given": "Ge" } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" }, { "id": "St-Clair-J-M", "name": { "family": "St. Clair", "given": "Jason M." }, "orcid": "0000-0002-9367-5749" }, { "id": "Crounse-J-D", "name": { "family": "Crounse", "given": "John D." }, "orcid": "0000-0001-5443-729X" }, { "id": "Wisthaler-A", "name": { "family": "Wisthaler", "given": "Armin" } }, { "id": "Mikoviny-T", "name": { "family": "Mikoviny", "given": "Tomas" } }, { "id": "Jimenez-J-L", "name": { "family": "Jimenez", "given": "Jose L." }, "orcid": "0000-0001-6203-1847" }, { "id": "Campuzano-Jost-P", "name": { "family": "Campuzano-Jost", "given": "Pedro" }, "orcid": "0000-0003-3930-010X" }, { "id": "Day-D-A", "name": { "family": "Day", "given": "Douglas A." }, "orcid": "0000-0003-3213-4233" }, { "id": "Hu-Weiwei", "name": { "family": "Hu", "given": "Weiwei" } }, { "id": "Ryerson-T-B", "name": { "family": "Ryerson", "given": "Thomas B." }, "orcid": "0000-0003-2800-7581" }, { "id": "Pollack-I-B", "name": { "family": "Pollack", "given": "Ilana B." }, "orcid": "0000-0001-7151-9756" }, { "id": "Peischl-J", "name": { "family": "Peischl", "given": "Jeff" }, "orcid": "0000-0002-9320-7101" }, { "id": "Anderson-B-E", "name": { "family": "Anderson", "given": "Bruce E." } }, { "id": "Ziemba-L-D", "name": { "family": "Ziemba", "given": "Luke D." } }, { "id": "Blake-D-R", "name": { "family": "Blake", "given": "Donald R." } }, { "id": "Meinardi-S", "name": { "family": "Meinardi", "given": "Simone" } }, { "id": "Diskin-G-S", "name": { "family": "Diskin", "given": "Glenn" }, "orcid": "0000-0002-3617-0269" } ] }, "title": "Airborne measurements of organosulfates over the continental U.S.", "ispublished": "pub", "full_text_status": "public", "keywords": "organosulfate; IEPOX sulfate; glycolic acid sulfate; free troposphere aerosols; aerosol acidity; relative humidity", "note": "\u00a9 2015 The Authors.\nThis 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 1 AUG 2014; Accepted 26 FEB 2015; Accepted article online 28 FEB 2015; Published online 3 APR 2015. \n\nThe majority of the study is supported by the NASA grant NNH12AT29I from the Upper Atmosphere Research Program, Radiation Sciences Program, and Tropospheric Chemistry Program and by NOAA base funding. The GA sulfate standard is based upon work supported by the National Science Foundation under grant CHE-1213723. IEPOX and ISOPOOH measurements were supported by NASA NNX12AC06G. PTR-MS measurements were supported by BMVIT/FFG-ALR (Austrian Space Applications Programme, ASAP), the NASA Postdoctoral Program (NPP), and the National Institute of Aerospace (NIA). NO and O3 measurements were supported by NASA grant NNH12AT30I. AMS measurements were supported by NASA NNX12AC03G, NSF AGS-1243354, and NOAA NA13OAR4310063. We thank Barbara Ervens at NOAA and University of Colorado, Boulder for helpful discussion. We also would like to thank all the NASA DC8 crew for their assistance to integrate, maintain, and deintegrate the instrument on the airplane. The data are publicly available at NASA data achieve https://www-air.larc.nasa.gov/cgi-bin/ArcView/dc3-seac4rs and http://www-air.larc.nasa.gov/missions/seac4rs/index.html. The analysis results are available upon requested from jin.liao@noaa.gov and karl.froyd@noaa.gov.\n\nPublished - jgrd52049.pdf
Supplemental Material - jgrd52049-sup-0001-supplementary.doc
", "abstract": "Organosulfates are important secondary organic aerosol (SOA) components and good tracers for aerosol heterogeneous reactions. However, the knowledge of their spatial distribution, formation conditions, and environmental impact is limited. In this study, we report two organosulfates, an isoprene-derived isoprene epoxydiols (IEPOX) (2,3-epoxy-2-methyl-1,4-butanediol) sulfate and a glycolic acid (GA) sulfate, measured using the NOAA Particle Analysis Laser Mass Spectrometer (PALMS) on board the NASA DC8 aircraft over the continental U.S. during the Deep Convective Clouds and Chemistry Experiment (DC3) and the Studies of Emissions and Atmospheric Composition, Clouds, and Climate Coupling by Regional Surveys (SEAC4RS). During these campaigns, IEPOX sulfate was estimated to account for 1.4% of submicron aerosol mass (or 2.2% of organic aerosol mass) on average near the ground in the southeast U.S., with lower concentrations in the western U.S. (0.2\u20130.4%) and at high altitudes (<0.2%). Compared to IEPOX sulfate, GA sulfate was more uniformly distributed, accounting for about 0.5% aerosol mass on average, and may be more abundant globally. A number of other organosulfates were detected; none were as abundant as these two. Ambient measurements confirmed that IEPOX sulfate is formed from isoprene oxidation and is a tracer for isoprene SOA formation. The organic precursors of GA sulfate may include glycolic acid and likely have both biogenic and anthropogenic sources. Higher aerosol acidity as measured by PALMS and relative humidity tend to promote IEPOX sulfate formation, and aerosol acidity largely drives in situ GA sulfate formation at high altitudes. This study suggests that the formation of aerosol organosulfates depends not only on the appropriate organic precursors but also on emissions of anthropogenic sulfur dioxide (SO_2), which contributes to aerosol acidity.", "date": "2015-04-16", "date_type": "published", "publication": "Journal of Geophysical Research. Atmospheres", "volume": "120", "number": "7", "publisher": "American Geophysical Union", "pagerange": "2990-3005", "id_number": "CaltechAUTHORS:20150526-081613980", "issn": "2169-897X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150526-081613980", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NNH12AT29I" }, { "agency": "NSF", "grant_number": "CHE-1213723" }, { "agency": "NASA", "grant_number": "NNX12AC06G" }, { "agency": "Bundesministerium f\u00fcr Verkehr, Innovation und Technologie (BMVIT)" }, { "agency": "NASA Postdoctoral Program" }, { "agency": "National Institute of Aerospace (NIA)" }, { "agency": "NASA", "grant_number": "NNH12AT30I" }, { "agency": "NASA", "grant_number": "NNX12AC03G" }, { "agency": "NSF", "grant_number": "AGS-1243354" }, { "agency": "National Oceanic and Atmospheric Administration (NOAA)", "grant_number": "NA13OAR4310063" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1002/2014JD022378", "pmcid": "PMC4677836", "primary_object": { "basename": "jgrd52049-sup-0001-supplementary.doc", "url": "https://authors.library.caltech.edu/records/n7x56-y3m51/files/jgrd52049-sup-0001-supplementary.doc" }, "related_objects": [ { "basename": "jgrd52049.pdf", "url": "https://authors.library.caltech.edu/records/n7x56-y3m51/files/jgrd52049.pdf" } ], "resource_type": "article", "pub_year": "2015", "author_list": "Liao, Jin; Froyd, Karl D.; et el." }, { "id": "https://authors.library.caltech.edu/records/wdxf2-rwm95", "eprint_id": 57558, "eprint_status": "archive", "datestamp": "2023-08-22 15:13:19", "lastmod": "2023-10-23 19:45:16", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Apel-E-C", "name": { "family": "Apel", "given": "E. C." } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Crounse-J-D", "name": { "family": "Crounse", "given": "J. D." }, "orcid": "0000-0001-5443-729X" } ] }, "title": "Upper tropospheric ozone production from lightning NO_x-impacted convection: Smoke ingestion case study from the DC3 campaign", "ispublished": "pub", "full_text_status": "public", "keywords": "storm convective outflow; biomass burning emission ratios; acrolein; hydrogen cyanide (HCN); acetonitrile (CH3CN); deep convective cloud and chemistry experiment (DC3)", "note": "\u00a9 2015 American Geophysical Union.\n\nReceived 2 JUN 2014; Accepted 31 JAN 2015; Accepted article online 6 FEB 2015; Published online 21 MAR 2015. \n\nThe data used in this paper are available from http://www-air.larc.nasa.gov/cgi-bin/ArcView/dc3-seac4rs and http://catalog.eol.ucar.edu/dc3_2012/index.html. The NCAR MM can be downloaded from the NCAR community data portal (http://cdp.ucar.edu/). The authors thank the crew and support team of the NSF/NCAR GV aircraft and Christine Wiedinmyer, Jeff Stith, and Shawn Honomichl for their helpful comments and discussion. The National Center for Atmospheric Research is sponsored by the National Science Foundation. Any opinions, findings, and conclusions or recommendations expressed in the publication are those of the authors and do not necessarily reflect the views of the National Science Foundation.\n\nPublished - jgrd51999.pdf
", "abstract": "As part of the Deep Convective Cloud and Chemistry (DC3) experiment, the National Science Foundation/National Center for Atmospheric Research (NCAR) Gulfstream-V (GV) and NASA DC-8 research aircraft probed the chemical composition of the inflow and outflow of two convective storms (north storm, NS, south storm, SS) originating in the Colorado region on 22 June 2012, a time when the High Park wildfire was active in the area. A wide range of trace species were measured on board both aircraft including biomass burning (BB) tracers hydrogen cyanide (HCN) and acetonitrile (ACN). Acrolein, a much shorter lived tracer for BB, was also quantified on the GV. The data demonstrated that the NS had ingested fresh smoke from the High Park fire and as a consequence had a higher VOC OH reactivity than the SS. The SS lofted aged fire tracers along with other boundary layer ozone precursors and was more impacted by lightning NO_x (LNO_x) than the NS. The NCAR master mechanism box model was initialized with measurements made in the outflow of the two storms. The NS and SS were predicted to produce 11 and 14\u2009ppbv of O_3, respectively, downwind of the storm over 2\u2009days. Sensitivity tests revealed that the ozone production potential of the SS was highly dependent on LNO_x. Normalized excess mixing ratios, \u0394X/\u0394CO, for HCN and ACN were determined in both the fire plume and the storm outflow and found to be 7.0\u2009\u00b1\u20090.5 and 2.3\u2009\u00b1\u20090.5\u2009pptv\u2009ppbv^(\u22121), respectively, and 1.4\u2009\u00b1\u20090.3\u2009pptv\u2009ppbv^(\u22121) for acrolein in the outflow only.", "date": "2015-03-27", "date_type": "published", "publication": "Journal of Geophysical Research. Atmospheres", "volume": "120", "number": "6", "publisher": "American Geophysical Union", "pagerange": "2505-2523", "id_number": "CaltechAUTHORS:20150515-091930292", "issn": "2169-897X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150515-091930292", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "National Center for Atmospheric Research (NCAR)" }, { "agency": "NSF" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1002/2014JD022121", "primary_object": { "basename": "jgrd51999.pdf", "url": "https://authors.library.caltech.edu/records/wdxf2-rwm95/files/jgrd51999.pdf" }, "resource_type": "article", "pub_year": "2015", "author_list": "Apel, E. C.; Wennberg, P. O.; et el." }, { "id": "https://authors.library.caltech.edu/records/t3a18-xxg05", "eprint_id": 53113, "eprint_status": "archive", "datestamp": "2023-08-22 14:54:49", "lastmod": "2023-10-19 14:33:17", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Nguyen-Tran-B", "name": { "family": "Nguyen", "given": "Tran B." } }, { "id": "Crounse-J-D", "name": { "family": "Crounse", "given": "John D." }, "orcid": "0000-0001-5443-729X" }, { "id": "Teng-Alex-P", "name": { "family": "Teng", "given": "Alex P." } }, { "id": "St-Clair-J-M", "name": { "family": "St. Clair", "given": "Jason M." }, "orcid": "0000-0002-9367-5749" }, { "id": "Paulot-F", "name": { "family": "Paulot", "given": "Fabien" }, "orcid": "0000-0001-7534-4922" }, { "id": "Wolfe-G-M", "name": { "family": "Wolfe", "given": "Glenn M." }, "orcid": "0000-0001-6586-4043" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "Rapid deposition of oxidized biogenic compounds to a temperate forest", "ispublished": "pub", "full_text_status": "public", "keywords": "biosphere\u2212atmosphere exchange | isoprene | dry deposition | OVOCs | fluxes", "note": "Copyright \u00a9 2015 National Academy of Sciences. Freely available online through the PNAS open access option. \n\nEdited by Mark H. Thiemens, University of California, San Diego, La Jolla, CA, and approved December 22, 2014 (received for review September 28, 2014) Published online before print January 20, 2015 \n\nWe thank the organizers and committee members of the SOAS campaign: A. G. Carlton, A. H. Goldstein, J. L. Jimenez, R. W. Pinder, J. de Gouw, B. J. Turpin, and A. B. Guenther. We acknowledge C. J. Groff at Purdue University for his help with leaf area index measurements and tree surveys. We thank D. J. Jacob and the Atmospheric Chemistry Modeling Group at Harvard University for making GEOS\u2212Chem available for this work. Meteorological data used in the GEOS\u2212Chem simulations were provided by the Global Modeling and Assimilation Office at NASA Goddard Space Flight Center. We acknowledge funding from the National Science Foundation (NSF) under Grant AGS-1240604 and NSF Postdoctoral Research Fellowship program Award AGS-1331360. Financial and logistical support for SOAS was provided by the NSF, the Earth Observing Laboratory at the National Center for Atmospheric Research (operated by NSF), the personnel at Atmospheric Research and Analysis, and the Electric Power Research Institute. \n\nAuthor contributions: P.O.W. designed research; T.B.N., J.D.C., A.P.T., J.M.S.C., F.P., and G.M.W. performed research; J.D.C. contributed new reagents/analytic tools; T.B.N. analyzed data; and T.B.N. and P.O.W. 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/lookup/suppl/doi:10.1073/pnas.1418702112/-/DCSupplemental.\n\nPublished - E392.full.pdf
Supplemental Material - pnas.1418702112.sapp.pdf
", "abstract": "We report fluxes and dry deposition velocities for 16 atmospheric compounds above a southeastern United States forest, including: hydrogen peroxide (H_2O_2), nitric acid (HNO_3), hydrogen cyanide (HCN), hydroxymethyl hydroperoxide, peroxyacetic acid, organic hydroxy nitrates, and other multifunctional species derived from the oxidation of isoprene and monoterpenes. The data suggest that dry deposition is the dominant daytime sink for small, saturated oxygenates. Greater than 6 wt %C emitted as isoprene by the forest was returned by dry deposition of its oxidized products. Peroxides account for a large fraction of the oxidant flux, possibly eclipsing ozone in more pristine regions. The measured organic nitrates comprise a sizable portion (15%) of the oxidized nitrogen input into the canopy, with HNO_3 making up the balance. We observe that water-soluble compounds (e.g., strong acids and hydroperoxides) deposit with low surface resistance whereas compounds with moderate solubility (e.g., organic nitrates and hydroxycarbonyls) or poor solubility (e.g., HCN) exhibited reduced uptake at the surface of plants. To first order, the relative deposition velocities of water-soluble compounds are constrained by their molecular diffusivity. From resistance modeling, we infer a substantial emission flux of formic acid at the canopy level (\u223c1 nmol m^(\u22122)\u22c5s^(\u22121)). GEOS\u2212Chem, a widely used atmospheric chemical transport model, currently underestimates dry deposition for most molecules studied in this work. Reconciling GEOS\u2212Chem deposition velocities with observations resulted in up to a 45% decrease in the simulated surface concentration of trace gases.", "date": "2015-02-03", "date_type": "published", "publication": "Proceedings of the National Academy of Sciences of the United States of America", "volume": "112", "number": "5", "publisher": "National Academy of Sciences", "pagerange": "E392-E401", "id_number": "CaltechAUTHORS:20141222-144149377", "issn": "0027-8424", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20141222-144149377", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "AGS-1240604" }, { "agency": "NSF Postdoctoral Fellowship", "grant_number": "AGS-1331360" }, { "agency": "National Center for Atmospheric Research (NCAR)" }, { "agency": "Electric Power Research Institute (EPRI)" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1073/pnas.1418702112", "pmcid": "PMC4321284", "primary_object": { "basename": "E392.full.pdf", "url": "https://authors.library.caltech.edu/records/t3a18-xxg05/files/E392.full.pdf" }, "related_objects": [ { "basename": "pnas.1418702112.sapp.pdf", "url": "https://authors.library.caltech.edu/records/t3a18-xxg05/files/pnas.1418702112.sapp.pdf" } ], "resource_type": "article", "pub_year": "2015", "author_list": "Nguyen, Tran B.; Crounse, John D.; et el." }, { "id": "https://authors.library.caltech.edu/records/j26c7-awn07", "eprint_id": 55065, "eprint_status": "archive", "datestamp": "2023-08-22 14:31:15", "lastmod": "2023-10-20 21:18:58", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Nguyen-Tran-B", "name": { "family": "Nguyen", "given": "T. B." } }, { "id": "Crounse-J-D", "name": { "family": "Crounse", "given": "J. D." }, "orcid": "0000-0001-5443-729X" }, { "id": "Schwantes-R-H", "name": { "family": "Schwantes", "given": "R. H." }, "orcid": "0000-0002-7095-3718" }, { "id": "Teng-Alex-P", "name": { "family": "Teng", "given": "A. P." } }, { "id": "Bates-K-H", "name": { "family": "Bates", "given": "K. H." }, "orcid": "0000-0001-7544-9580" }, { "id": "Zhang-Xuan", "name": { "family": "Zhang", "given": "X." } }, { "id": "St-Clair-J-M", "name": { "family": "St. Clair", "given": "J. M." }, "orcid": "0000-0002-9367-5749" }, { "id": "Brune-W-H", "name": { "family": "Brune", "given": "W. H." }, "orcid": "0000-0002-1609-4051" }, { "id": "Tyndall-G-S", "name": { "family": "Tyndall", "given": "G. S." } }, { "id": "Keutsch-F-N", "name": { "family": "Keutsch", "given": "F. N." } }, { "id": "Seinfeld-J-H", "name": { "family": "Seinfeld", "given": "J. H." }, "orcid": "0000-0003-1344-4068" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "Overview of the Focused Isoprene eXperiment at the California Institute of Technology (FIXCIT): mechanistic chamber studies on the oxidation of biogenic compounds", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2014 Author(s). \n\nReceived: 27 July 2014. Published in Atmos. Chem. Phys. Discuss.: 25 August 2014. Revised: 10 November 2014. Accepted: 20 November 2014. Published: 19 December 2014. \n\nWe acknowledge the collaborative efforts of FIXCIT participants (Tables 2 and 3), as well as the organizers and logistics personnel for SOAS 2013. FIXCIT was made possible by the support from multiple agencies: the US National Science Foundation (NSF) under grants AGS-1240604 (Caltech), AGS-1246918 (PSU), AGS-1247421 (UWM), AGS-1243354 (CU/ARI), AGS-1240611 (CSU), and AGS-1120076 (UCB); the US Department of Energy under grant DE-SC0006626 (Caltech); and the US Environmental Protection Agency (EPA) under STAR grant 835407 (PNNL/UCB/SUNY). T. B. Nguyen (Caltech) was supported by the NSF Postdoctoral Research Fellowship program, award AGS-1331360. NCAR is operated under the sponsorship of the NSF. Edited by: N. L. Ng\n\nPublished - acp-14-13531-2014.pdf
", "abstract": "The Focused Isoprene eXperiment at the California Institute of Technology (FIXCIT) was a collaborative atmospheric chamber campaign that occurred during January 2014. FIXCIT is the laboratory component of a synergistic field and laboratory effort aimed toward (1) better understanding the chemical details behind ambient observations relevant to the southeastern United States, (2) advancing the knowledge of atmospheric oxidation mechanisms of important biogenic hydrocarbons, and (3) characterizing the behavior of field instrumentation using authentic standards. Approximately 20 principal scientists from 14 academic and government institutions performed parallel measurements at a forested site in Alabama and at the atmospheric chambers at Caltech. During the 4 week campaign period, a series of chamber experiments was conducted to investigate the dark- and photo-induced oxidation of isoprene, \u03b1-pinene, methacrolein, pinonaldehyde, acylperoxy nitrates, isoprene hydroxy nitrates (ISOPN), isoprene hydroxy hydroperoxides (ISOPOOH), and isoprene epoxydiols (IEPOX) in a highly controlled and atmospherically relevant manner. Pinonaldehyde and isomer-specific standards of ISOPN, ISOPOOH, and IEPOX were synthesized and contributed by campaign participants, which enabled explicit exploration into the oxidation mechanisms and instrument responses for these important atmospheric compounds. The present overview describes the goals, experimental design, instrumental techniques, and preliminary observations from the campaign. This work provides context for forthcoming publications affiliated with the FIXCIT campaign. Insights from FIXCIT are anticipated to aid significantly in interpretation of field data and the revision of mechanisms currently implemented in regional and global atmospheric models.", "date": "2014-12-19", "date_type": "published", "publication": "Atmospheric Chemistry and Physics Discussions", "volume": "14", "number": "24", "publisher": "European Geosciences Union", "pagerange": "13531-13549", "id_number": "CaltechAUTHORS:20150220-132616278", "issn": "1680-7367", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150220-132616278", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "AGS-1240604" }, { "agency": "NSF", "grant_number": "AGS-1246918" }, { "agency": "NSF", "grant_number": "AGS-1247421" }, { "agency": "NSF", "grant_number": "AGS-1243354" }, { "agency": "NSF", "grant_number": "AGS-1240611" }, { "agency": "NSF", "grant_number": "AGS-1120076" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0006626" }, { "agency": "Environmental Protection Agency (EPA)", "grant_number": "835407" }, { "agency": "NSF Postdoctoral Fellowship", "grant_number": "AGS-1331360" }, { "agency": "NSF" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/acp-14-13531-2014", "primary_object": { "basename": "acp-14-13531-2014.pdf", "url": "https://authors.library.caltech.edu/records/j26c7-awn07/files/acp-14-13531-2014.pdf" }, "resource_type": "article", "pub_year": "2014", "author_list": "Nguyen, T. B.; Crounse, J. D.; et el." }, { "id": "https://authors.library.caltech.edu/records/zqqhe-6ss59", "eprint_id": 55043, "eprint_status": "archive", "datestamp": "2023-08-22 14:30:33", "lastmod": "2023-10-20 21:16:44", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Rivera-Rios-J-C", "name": { "family": "Rivera-Rios", "given": "J. C." } }, { "id": "Nguyen-Tran-B", "name": { "family": "Nguyen", "given": "T. B." } }, { "id": "Crounse-J-D", "name": { "family": "Crounse", "given": "J. D." }, "orcid": "0000-0001-5443-729X" }, { "id": "Jud-W", "name": { "family": "Jud", "given": "W." } }, { "id": "St-Clair-J-M", "name": { "family": "St. Clair", "given": "J. M." }, "orcid": "0000-0002-9367-5749" }, { "id": "Mikoviny-T", "name": { "family": "Mikoviny", "given": "T." } }, { "id": "Gilman-J-B", "name": { "family": "Gilman", "given": "J. B." } }, { "id": "Lerner-B-M", "name": { "family": "Lerner", "given": "B. M." } }, { "id": "Kaiser-J-B", "name": { "family": "Kaiser", "given": "J. B." } }, { "id": "de-Gouw-J-A", "name": { "family": "de Gouw", "given": "J." }, "orcid": "0000-0002-0385-1826" }, { "id": "Wisthaler-A", "name": { "family": "Wisthaler", "given": "A." } }, { "id": "Hansel-A", "name": { "family": "Hansel", "given": "A." } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Seinfeld-J-H", "name": { "family": "Seinfeld", "given": "J. H." }, "orcid": "0000-0003-1344-4068" }, { "id": "Keutsch-F-N", "name": { "family": "Keutsch", "given": "F. N." } } ] }, "title": "Conversion of hydroperoxides to carbonyls in field and laboratory instrumentation: Observational bias in diagnosing pristine versus anthropogenically controlled atmospheric chemistry", "ispublished": "pub", "full_text_status": "public", "keywords": "Isoprene-oxidation; hydroperoxides; anthropogenic influence; secondary pollutant formation; interference", "note": "\u00a9 2014 American Geophysical Union. Received 18 Sep 2014.\nAccepted 12 Nov 2014. Accepted article online 17 Nov 2014.\nPublished online 8 Dec 2014. \n\nJ.C.R., J.B.K., and F.N.K. thank NSF-AGS (1247421) for the support. J.B.K. also acknowledges support from the National\nScience Foundation Graduate Research Fellowship Program under grant DGE-1256259. J.D.C., T.B.N., J.S., and P.O.W.\nthank NSF grant AGS-1240604 for the support. T.B.N. also acknowledges support from the National Science Foundation\nFellowship grant AGS-1331360. This work was financially supported by the Austrian Science Fund (FWF) under the project I655-B16. A.W. and T.M. acknowledge support through the Austrian Space Applications Program of the Austrian\nFederal Ministry for Transport, Innovation, and Technology (bmvit) and through the Visiting Scientist Program at the National Institute of Aerospace. Compound characterization, additional figures, and experimental details are available online as supporting information.\n\nThe Editor thanks two anonymous reviewers for their assistance in evaluating this paper.\n\nPublished - Rivera_Rios_et_al-2014-Geophysical_Research_Letters.pdf
Supplemental Material - grl52356-sup-0001-documentS1.docx
", "abstract": "Atmospheric volatile organic compound (VOC) oxidation mechanisms under pristine (rural/remote) and urban (anthropogenically-influenced) conditions follow distinct pathways due to large differences in nitrogen oxide (NO_x) concentrations. These two pathways lead to products that have different chemical and physical properties and reactivity. Under pristine conditions, isoprene hydroxy hydroperoxides (ISOPOOHs) are the dominant first-generation isoprene oxidation products. Utilizing authentic ISOPOOH standards, we demonstrate that two of the most commonly used methods of measuring VOC oxidation products (i.e., gas chromatography and proton transfer reaction mass spectrometry) observe these hydroperoxides as their equivalent high-NO isoprene oxidation products \u2013 methyl vinyl ketone (MVK) and methacrolein (MACR). This interference has led to an observational bias affecting our understanding of global atmospheric processes. Considering these artifacts will help close the gap on discrepancies regarding the identity and fate of reactive organic carbon, revise our understanding of surface-atmosphere exchange of reactive carbon and SOA formation, and improve our understanding of atmospheric oxidative capacity.", "date": "2014-12-16", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "41", "number": "23", "publisher": "American Geophysical Union", "pagerange": "8645-8651", "id_number": "CaltechAUTHORS:20150220-091742441", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150220-091742441", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "AGS-1247421" }, { "agency": "NSF Graduate Research Fellowship", "grant_number": "DGE-1256259" }, { "agency": "NSF", "grant_number": "AGS-1240604" }, { "agency": "NSF", "grant_number": "AGS-1331360" }, { "agency": "Austrian Science Fund (FWF)", "grant_number": "I655-B16" }, { "agency": "Austrian Space Applications Program of the Austrian Federal Ministry for Transport, Innovation, and Technology" }, { "agency": "National Institute of Aerospace Visiting Scientist Program" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1002/2014GL061919", "primary_object": { "basename": "Rivera_Rios_et_al-2014-Geophysical_Research_Letters.pdf", "url": "https://authors.library.caltech.edu/records/zqqhe-6ss59/files/Rivera_Rios_et_al-2014-Geophysical_Research_Letters.pdf" }, "related_objects": [ { "basename": "grl52356-sup-0001-documentS1.docx", "url": "https://authors.library.caltech.edu/records/zqqhe-6ss59/files/grl52356-sup-0001-documentS1.docx" } ], "resource_type": "article", "pub_year": "2014", "author_list": "Rivera-Rios, J. C.; Nguyen, T. B.; et el." }, { "id": "https://authors.library.caltech.edu/records/dggqy-qwg88", "eprint_id": 53037, "eprint_status": "archive", "datestamp": "2023-08-22 14:12:51", "lastmod": "2023-10-18 21:53:43", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Agust\u00ed-Panareda-A", "name": { "family": "Agust\u00ed-Panareda", "given": "A." } }, { "id": "Massart-S", "name": { "family": "Massart", "given": "S." }, "orcid": "0000-0002-7576-6188" }, { "id": "Chevallier-F", "name": { "family": "Chevallier", "given": "F." }, "orcid": "0000-0002-4327-3813" }, { "id": "Bousetta-S", "name": { "family": "Bousetta", "given": "S." } }, { "id": "Balsamo-G", "name": { "family": "Balsamo", "given": "G." } }, { "id": "Beljaars-A", "name": { "family": "Beljaars", "given": "A." } }, { "id": "Ciais-P", "name": { "family": "Ciais", "given": "P." }, "orcid": "0000-0001-8560-4943" }, { "id": "Deutscher-N-M", "name": { "family": "Deutscher", "given": "N. M." }, "orcid": "0000-0002-2906-2577" }, { "id": "Engelen-R", "name": { "family": "Engelen", "given": "R." }, "orcid": "0000-0003-1577-5143" }, { "id": "Jones-L", "name": { "family": "Jones", "given": "L." } }, { "id": "Kivi-R", "name": { "family": "Kivi", "given": "R." } }, { "id": "Parise-J-D", "name": { "family": "Parise", "given": "J.-D." } }, { "id": "Peuch-V-H", "name": { "family": "Peuch", "given": "V.-H." } }, { "id": "Sherlock-V", "name": { "family": "Sherlock", "given": "V." } }, { "id": "Vermeulen-A-T", "name": { "family": "Vermeulen", "given": "A. T." }, "orcid": "0000-0002-8158-8787" }, { "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" } ] }, "title": "Forecasting global atmospheric CO_2", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2014 Author(s). CC Attribution 3.0 License. \n\nReceived: 1 April 2014. Published in Atmos. Chem. Phys. Discuss.: 27 May 2014. Revised: 8 September 2014. Accepted: 8 September 2014. Published: 14 November 2014. Edited by: S. Galmarini.\n\nThis study was funded by the European Commission under the EU Seventh Research Framework Programme (grant agreement No. 283576, MACC II). The ICOS data were obtained from the ICOS Atmospheric Thematic Center (Laboratoire des Sciences du Climat et l'Environnement) website at https://icos-atc-demo.lsce.ipsl.fr. The authors acknowledge the\nEuropean Commission for the support of the preparatory phase of ICOS (2008\u20132013), the Netherlands Ministry of IenM and ECN for the support of the observations at Cabauw, and the monitoring network SNO-RAMCES/ICOS-France which is in charge of Ivittuut, Mace Head and Lamto stations with the support of CNRS, CEA and OVSQ. Thanks to F. Truong (LSCE) and to A. Diawara and Y. Palmer for the maintenance of Station G\u00e9ophysique de LAMTO with the support of University of Abidjan. Thanks to J. L. Bonne and M. Delmotte for the data from Ivittuut station, with the support of Greenland's Kommando, Danish Armed Forces, Island Commander Greenland and Kommuneqarfik Sermersooq. Thanks to V. Kazan and G. Spain for the maintenance of Mace Head station with the support of the Irish Environmental Protection Agency, and the National University of Ireland, Galway. Thanks to\nHarri Portin, Juha Hatakka, Tuomas Laurila (FMI) for providing the data from the ICOS station at Puijo, Finland. We are grateful to J\u00e9r\u00f4me Tarniewicz for his technical support with the ICOS database and to Miha Razinger for his help in the development and maintenance of the ICOS monitoring plots in the MACC website. Thanks to the NOAA/ESRL Global Monitoring Division for providing their data from the baseline observatories at Barrow (Alaska), American Samoa, South Pole (Antarctica), the tall towers\nat Argyle (Maine), Park Falls (Wisconsin), West Branch (Iowa), and the vertical profiles from the NOAA GMD Carbon Cycle Vertical Profile Network. 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/. We acknowledge financial support of the Bialystok TCCON site from the Senate of Bremen and EU projects IMECC, GEOmon and InGOS, as well as maintenance and logistical work provided by the AeroMeteo Service and additional operational funding from the National Institute for Environmental Studies (NIES, Japan).\nPOW and DW thank NASA's Carbon Cycle Science program \n(NNX10AT83G and NNX11AG01G) and the Orbiting Carbon Observatory Program for support of TCCON and this research.\nThe HIPPO Merged 10 s data set was obtained from the website\nat http://hippo.ornl.gov/dataaccess. The HIPPO Programme was\nsupported by NSF grants ATM-0628575, ATM-0628519 and \nATM-0628388 to Harvard University, University of California (San Diego), University Corporation for Atmospheric Research, NOAA Earth System Research Laboratory, University of Colorado/CIRES and by the NCAR. The NCAR is supported by the National Science Foundation. The feedback from Britton Stephens is greatly appreciated.\n\nPublished - acp-14-11959-2014.pdf
", "abstract": "A new global atmospheric carbon dioxide (CO_2) real-time forecast is now available as part of the pre-operational Monitoring of Atmospheric Composition and Climate \u2013 Interim Implementation (MACC-II) service using the infrastructure of the European Centre for Medium-Range Weather Forecasts (ECMWF) Integrated Forecasting System (IFS). One of the strengths of the CO_2 forecasting system is that the land surface, including vegetation CO_2 fluxes, is modelled online within the IFS. Other CO_2 fluxes are prescribed from inventories and from off-line statistical and physical models. The CO_2 forecast also benefits from the transport modelling from a state-of-the-art numerical weather prediction (NWP) system initialized daily with a wealth of meteorological observations. This paper describes the capability of the forecast in modelling the variability of CO_2 on different temporal and spatial scales compared to observations. The modulation of the amplitude of the CO_2 diurnal cycle by near-surface winds and boundary layer height is generally well represented in the forecast. The CO_2 forecast also has high skill in simulating day-to-day synoptic variability. In the atmospheric boundary layer, this skill is significantly enhanced by modelling the day-to-day variability of the CO_2 fluxes from vegetation compared to using equivalent monthly mean fluxes with a diurnal cycle. However, biases in the modelled CO_2 fluxes also lead to accumulating errors in the CO_2 forecast. These biases vary with season with an underestimation of the amplitude of the seasonal cycle both for the CO_2 fluxes compared to total optimized fluxes and the atmospheric CO_2 compared to observations. The largest biases in the atmospheric CO_2 forecast are found in spring, corresponding to the onset of the growing season in the Northern Hemisphere. In the future, the forecast will be re-initialized regularly with atmospheric CO_2 analyses based on the assimilation of CO_2 products retrieved from satellite measurements and CO_2 in situ observations, as they become available in near-real time. In this way, the accumulation of errors in the atmospheric CO_2 forecast will be reduced. Improvements in the CO_2 forecast are also expected with the continuous developments in the operational IFS.", "date": "2014-11-14", "date_type": "published", "publication": "Atmospheric Chemistry and Physics", "volume": "14", "number": "21", "publisher": "European Geosciences Union", "pagerange": "11959-11983", "id_number": "CaltechAUTHORS:20141219-104743832", "issn": "1680-7316", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20141219-104743832", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "European Research Council (ERC)", "grant_number": "283576, MACC II" }, { "agency": "European Commission", "grant_number": "ICOS (2008\u20132013)" }, { "agency": "Centre National de la Recherche Scientifique (CNRS)" }, { "agency": "Commissariat \u00e0 l'Energie Atomique (CEA)" }, { "agency": "OVSQ" }, { "agency": "University of Abidjan" }, { "agency": "Greenland's Kommando" }, { "agency": "Danish Armed Forces" }, { "agency": "Island Commander Greenland" }, { "agency": "Kommuneqarfik Sermersooq" }, { "agency": "Environmental Protection Agency (Ireland)" }, { "agency": "National University of Ireland, Galway" }, { "agency": "Bialystok TCCON Senate of Bremen" }, { "agency": "EU projects IMECC, GEOmon and InGOS" }, { "agency": "National Institute for Environmental Studies (Japan)" }, { "agency": "NASA", "grant_number": "NNX10AT83G" }, { "agency": "NASA", "grant_number": "NNX11AG01G" }, { "agency": "NASA Orbiting Carbon Observatory" }, { "agency": "NSF", "grant_number": "ATM-0628575" }, { "agency": "NSF", "grant_number": "ATM-0628519" }, { "agency": "NSF", "grant_number": "ATM-0628388" }, { "agency": "University of California (San Diego)" }, { "agency": "University Corporation for Atmospheric Research" }, { "agency": "National Oceanic and Atmospheric Administration (NOAA)" }, { "agency": "University of Colorado/CIRES" }, { "agency": "National Center for Atmospheric Research (NCAR)" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/acp-14-11959-2014", "primary_object": { "basename": "acp-14-11959-2014.pdf", "url": "https://authors.library.caltech.edu/records/dggqy-qwg88/files/acp-14-11959-2014.pdf" }, "resource_type": "article", "pub_year": "2014", "author_list": "Agust\u00ed-Panareda, A.; Massart, S.; et el." }, { "id": "https://authors.library.caltech.edu/records/y7095-twt24", "eprint_id": 50586, "eprint_status": "archive", "datestamp": "2023-08-22 13:41:18", "lastmod": "2023-10-17 23:57:18", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Deutscher-N-M", "name": { "family": "Deutscher", "given": "N. M." }, "orcid": "0000-0002-2906-2577" }, { "id": "Sherlock-V", "name": { "family": "Sherlock", "given": "V." } }, { "id": "Mikaloff-Fletcher-S-E", "name": { "family": "Mikaloff Fletcher", "given": "S. E." } }, { "id": "Griffith-D-W-T", "name": { "family": "Griffith", "given": "D. W. T." }, "orcid": "0000-0002-7986-1924" }, { "id": "Notholt-J", "name": { "family": "Notholt", "given": "J." } }, { "id": "Macatangay-R", "name": { "family": "Macatangay", "given": "R." } }, { "id": "Connor-B-J", "name": { "family": "Connor", "given": "B. J." } }, { "id": "Robinson-J", "name": { "family": "Robinson", "given": "J." } }, { "id": "Shiona-H", "name": { "family": "Shiona", "given": "H." } }, { "id": "Velazco-V-A", "name": { "family": "Velazco", "given": "V. A." }, "orcid": "0000-0002-1376-438X" }, { "id": "Wang-Y", "name": { "family": "Wang", "given": "Y." } }, { "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" } ] }, "title": "Drivers of column-average CO_2 variability at Southern Hemispheric Total Carbon Column Observing Network sites", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 Author(s) 2014. This work is distributed under the Creative Commons Attribution 3.0 License.\n\nReceived: 10 April 2013; Published in Atmos. Chem. Phys. Discuss.: 3 June 2013; Revised: 22 July 2014; Accepted: 13 August 2014; Published: 18 September 2014.\n\nTCCON is funded by grant NNX11AG01G from NASA's Carbon Cycle Science Program. Measurements at Darwin are supported by Australian Research Council grant DP0879468 and NASA's Orbiting Carbon Observatory Project. The Lauder TCCON programme and TM3 model simulations are funded by NIWA under the New Zealand Greenhouse Gas Emissions, Mitigation, and Carbon Cycle Science Programme, and under the NZ Foundation of Research Science and Technology contracts C01X0204 and COX10406. CarbonTracker 2011_oi results provided by NOAA ESRL, Boulder, Colorado, USA from\nthe website at http://carbontracker.noaa.gov. This work was also made possible by an RSNZ ISAT bilateral exchange grant and by grants from the Australian Research Council and Department of Innovation, Industry, Science and Research International Science Linkages project CG130014. Support for this work was also provided by the ESA GHG-CCI project. We gratefully acknowledge operational assistance from staff at the ARM site in Darwin. The authors acknowledge the constructive input of the two anonymous referees, whose feedback resulted in a much improved manuscript.\nEdited by: T. R\u00f6ckmann\n\nPublished - acp-14-9883-2014.pdf
", "abstract": "We investigate factors that drive the variability in total column CO_2 at the Total Carbon Column Observing Network sites in the Southern Hemisphere using fluxes tagged by process and by source region from the CarbonTracker analysed product as well as the Simple Biosphere model. We show that the terrestrial biosphere is the largest driver of variability in the Southern Hemisphere column CO_2. However, it does not dominate in the same fashion as in the Northern Hemisphere. Local- and hemispheric-scale biomass burning can also play an important role, particularly at the tropical site, Darwin. The magnitude of seasonal variability in the column-average dry-air mole fraction of CO_2, X_CO_2, is also much smaller in the Southern Hemisphere and comparable in magnitude to the annual increase. Comparison of measurements to the model simulations highlights that there is some discrepancy between the two time series, especially in the early part of the Darwin data record. We show that this mismatch is most likely due to erroneously estimated local fluxes in the Australian tropical region, which are associated with enhanced photosynthesis caused by early rainfall during the tropical monsoon season.", "date": "2014-09-18", "date_type": "published", "publication": "Atmospheric Chemistry and Physics", "volume": "14", "number": "18", "publisher": "European Geosciences Union", "pagerange": "9883-9901", "id_number": "CaltechAUTHORS:20141020-161537740", "issn": "1680-7316", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20141020-161537740", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NNX11AG01G" }, { "agency": "Australian Research Council", "grant_number": "DP0879468" }, { "agency": "NIWA New Zealand Greenhouse Gas Emissions, Mitigation, and Carbon Cycle Science Programme" }, { "agency": "New Zealand Foundation of Research Science and Technology", "grant_number": "C01X0204" }, { "agency": "New Zealand Foundation of Research Science and Technology", "grant_number": "COX10406" }, { "agency": "RSNZ ISAT bilateral exchange grant" }, { "agency": "Department of Innovation, Industry, Science and Research (Australia)", "grant_number": "CG130014" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/acp-14-9883-2014", "primary_object": { "basename": "acp-14-9883-2014.pdf", "url": "https://authors.library.caltech.edu/records/y7095-twt24/files/acp-14-9883-2014.pdf" }, "resource_type": "article", "pub_year": "2014", "author_list": "Deutscher, N. M.; Sherlock, V.; et el." }, { "id": "https://authors.library.caltech.edu/records/6tt6s-cpn45", "eprint_id": 103553, "eprint_status": "archive", "datestamp": "2023-08-22 13:39:30", "lastmod": "2023-10-20 16:29:19", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Saad-K-M", "name": { "family": "Saad", "given": "K. M." }, "orcid": "0000-0002-2501-6223" }, { "id": "Wunch-D", "name": { "family": "Wunch", "given": "D." }, "orcid": "0000-0002-4924-0377" }, { "id": "Toon-G-C", "name": { "family": "Toon", "given": "G. C." }, "orcid": "0000-0003-4174-7541" }, { "id": "Bernath-P-F", "name": { "family": "Bernath", "given": "P." } }, { "id": "Boone-C-D", "name": { "family": "Boone", "given": "C." } }, { "id": "Connor-B", "name": { "family": "Connor", "given": "B." } }, { "id": "Deutscher-N-M", "name": { "family": "Deutscher", "given": "N. M." }, "orcid": "0000-0002-2906-2577" }, { "id": "Griffith-D-W-T", "name": { "family": "Griffith", "given": "D. W. T." }, "orcid": "0000-0002-7986-1924" }, { "id": "Kivi-R", "name": { "family": "Kivi", "given": "R." }, "orcid": "0000-0001-8828-2759" }, { "id": "Notholt-J", "name": { "family": "Notholt", "given": "J." } }, { "id": "Roehl-C-M", "name": { "family": "Roehl", "given": "C." }, "orcid": "0000-0001-5383-8462" }, { "id": "Schneider-M", "name": { "family": "Schneider", "given": "M." } }, { "id": "Sherlock-V", "name": { "family": "Sherlock", "given": "V." } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "Derivation of tropospheric methane from TCCON CH\u2084 and HF total column observations", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 Author(s) 2014. This work is distributed under the Creative Commons Attribution 3.0 License. \n\nReceived: 15 Feb 2014 \u2013 Discussion started: 07 Apr 2014 \u2013 Revised: 18 Jul 2014 \u2013 Accepted: 06 Aug 2014 \u2013 Published: 10 Sep 2014. \n\nSupport for this research was received from NASA's Carbon Cycle Science program (NNX10AT83G, James Randerson, PI). Part of this work was performed at the Jet Propulsion Laboratory, California Institute of Technology, under contract with NASA. US funding for TCCON comes from NASA grants NNX11AG01G, NAG5-12247, NNG05-GD07G, and NASA Orbiting Carbon Observatory Program. We are grateful to the DOE ARM program for technical support in Lamont and Darwin and Jeff Ayers for technical support in Park Falls. European funding is from GEOMON, InGOS, and IMECC. From 2004 to 2011 the Lauder TCCON program was funded by the New Zealand Foundation of Research Science and Technology contracts CO1X0204, CO1X0703 and CO1X0406. Since 2011 the program has been funded by NIWA's Atmosphere Research Programme 3 (2011/13 Statement of Corporate Intent). Australian funding is from the Australian Research Council, DP0879468 and LP0562346. Funding for the ACE-FTS mission is primarily provided by the Canadian Space Agency. NCEP Reanalysis data are provided by NOAA/OAR/ESRL PSD. SGP aircraft flask data were obtained through the ARM Program sponsored by the US Department of Energy, Office of Science, Office of Biological and Environmental Research and were generated by NOAA-ESRL, Carbon Cycle Greenhouse Gases Group. Baring Head NIWA surface data were provided courtesy of Gordon Brailsford, Dave Lowe and Ross Martin. We would also acknowledge the contributions of in situ vertical profiles from the HIPPO, IMECC, INTEX, Learjet, and START08 campaigns. Color schemes for Figs. 1 and 3 are from Brewer, Cynthia A., 200x. http://www.ColorBrewer.org. \n\nEdited by: G. Stiller\n\nPublished - amt-7-2907-2014.pdf
", "abstract": "The Total Carbon Column Observing Network (TCCON) is a global ground-based network of Fourier transform spectrometers that produce precise measurements of column-averaged dry-air mole fractions of atmospheric methane (CH\u2084). Temporal variability in the total column of CH\u2084 due to stratospheric dynamics obscures fluctuations and trends driven by tropospheric transport and local surface fluxes that are critical for understanding CH\u2084 sources and sinks. We reduce the contribution of stratospheric variability from the total column average by subtracting an estimate of the stratospheric CH\u2084 derived from simultaneous measurements of hydrogen fluoride (HF). HF provides a proxy for stratospheric CH\u2084 because it is strongly correlated to CH\u2084 in the stratosphere, has an accurately known tropospheric abundance (of zero), and is measured at most TCCON stations. The stratospheric partial column of CH\u2084 is calculated as a function of the zonal and annual trends in the relationship between CH\u2084 and HF in the stratosphere, which we determine from ACE-FTS satellite data. We also explicitly take into account the CH\u2084 column averaging kernel to estimate the contribution of stratospheric CH\u2084 to the total column. The resulting tropospheric CH\u2084 columns are consistent with in situ aircraft measurements and augment existing observations in the troposphere.", "date": "2014-09-10", "date_type": "published", "publication": "Atmospheric Measurement Techniques", "volume": "7", "number": "9", "publisher": "European Geosciences Union", "pagerange": "2907-2918", "id_number": "CaltechAUTHORS:20200529-093432972", "issn": "1867-8548", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200529-093432972", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NNX10AT83G" }, { "agency": "NASA/JPL/Caltech" }, { "agency": "NASA", "grant_number": "NNX11AG01G" }, { "agency": "NASA", "grant_number": "NAG5-12247" }, { "agency": "NASA", "grant_number": "NNG05-GD07G" }, { "agency": "Orbiting Carbon Observatory (OCO)" }, { "agency": "Department of Energy (DOE)" }, { "agency": "New Zealand Foundation of Research Science and Technology", "grant_number": "CO1X0204" }, { "agency": "New Zealand Foundation of Research Science and Technology", "grant_number": "CO1X0703" }, { "agency": "New Zealand Foundation of Research Science and Technology", "grant_number": "CO1X0406" }, { "agency": "National Institute of Water and Atmospheric Research (NIWA)" }, { "agency": "Australian Research Council", "grant_number": "DP0879468" }, { "agency": "Australian Research Council", "grant_number": "LP0562346" }, { "agency": "Canadian Space Agency (CSA)" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/amt-7-2907-2014", "primary_object": { "basename": "amt-7-2907-2014.pdf", "url": "https://authors.library.caltech.edu/records/6tt6s-cpn45/files/amt-7-2907-2014.pdf" }, "resource_type": "article", "pub_year": "2014", "author_list": "Saad, K. M.; Wunch, D.; et el." }, { "id": "https://authors.library.caltech.edu/records/m0s00-1eg33", "eprint_id": 103560, "eprint_status": "archive", "datestamp": "2023-08-22 13:25:50", "lastmod": "2023-10-20 16:29:41", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Nguyen-H", "name": { "family": "Nguyen", "given": "H." } }, { "id": "Osterman-G-B", "name": { "family": "Osterman", "given": "G." } }, { "id": "Wunch-D", "name": { "family": "Wunch", "given": "D." }, "orcid": "0000-0002-4924-0377" }, { "id": "O'Dell-C-W", "name": { "family": "O'Dell", "given": "C." } }, { "id": "Mandrake-L", "name": { "family": "Mandrake", "given": "L." } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P." }, "orcid": "0000-0002-6126-3854" }, { "id": "Fisher-B-M", "name": { "family": "Fisher", "given": "B." } }, { "id": "Castano-R", "name": { "family": "Castano", "given": "R." } } ] }, "title": "A method for colocating satellite X_(CO\u2082) data to ground-based data and its application to ACOS-GOSAT and TCCON", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 Author(s) 2014. This work is distributed under the Creative Commons Attribution 3.0 License. \n\nReceived: 15 Jan 2014 \u2013 Discussion started: 14 Feb 2014 \u2013 Revised: 25 Jun 2014 \u2013 Accepted: 30 Jun 2014 \u2013 Published: 19 Aug 2014. \n\nThis research was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with NASA. ACOS data are obtained from Goddard Earth Sciences Data and Information Services Center, operated by NASA, from the website http://disc.sci.gsfc.nasa.gov/acdisc/documentation/ACOS.shtml. 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/. NCEP reanalysis data are provided by the NOAA/OAR/ESRL PSD, Boulder, Colorado, USA, from their website at http://www.cdc.noaa.gov/. \n\nEdited by: W. R. Simpson.\n\nPublished - amt-7-2631-2014.pdf
", "abstract": "Satellite measurements are often compared with higher-precision ground-based measurements as part of validation efforts. The satellite soundings are rarely perfectly coincident in space and time with the ground-based measurements, so a colocation methodology is needed to aggregate \"nearby\" soundings into what the instrument would have seen at the location and time of interest. We are particularly interested in validation efforts for satellite-retrieved total column carbon dioxide (X_(CO\u2082)), where X_(CO\u2082) data from Greenhouse Gas Observing Satellite (GOSAT) retrievals (ACOS, NIES, RemoteC, PPDF, etc.) or SCanning Imaging Absorption SpectroMeter for Atmospheric CHartographY (SCIAMACHY) are often colocated and compared to ground-based column X_(CO\u2082) measurement from Total Carbon Column Observing Network (TCCON). \n\nCurrent colocation methodologies for comparing satellite measurements of total column dry-air mole fractions of CO\u2082 (X_(CO\u2082)) with ground-based measurements typically involve locating and averaging the satellite measurements within a latitudinal, longitudinal, and temporal window. We examine a geostatistical colocation methodology that takes a weighted average of satellite observations depending on the \"distance\" of each observation from a ground-based location of interest. The \"distance\" function that we use is a modified Euclidian distance with respect to latitude, longitude, time, and midtropospheric temperature at 700 hPa. We apply this methodology to X_(CO\u2082) retrieved from GOSAT spectra by the ACOS team, cross-validate the results to TCCON X_(CO\u2082) ground-based data, and present some comparisons between our methodology and standard existing colocation methods showing that, in general, geostatistical colocation produces smaller mean-squared error.", "date": "2014-08-19", "date_type": "published", "publication": "Atmospheric Measurement Techniques", "volume": "7", "number": "8", "publisher": "European Geosciences Union", "pagerange": "2631-2644", "id_number": "CaltechAUTHORS:20200529-093433983", "issn": "1867-8548", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200529-093433983", "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-7-2631-2014", "primary_object": { "basename": "amt-7-2631-2014.pdf", "url": "https://authors.library.caltech.edu/records/m0s00-1eg33/files/amt-7-2631-2014.pdf" }, "resource_type": "article", "pub_year": "2014", "author_list": "Nguyen, H.; Osterman, G.; et el." }, { "id": "https://authors.library.caltech.edu/records/zvm93-53n26", "eprint_id": 46554, "eprint_status": "archive", "datestamp": "2023-08-22 12:44:08", "lastmod": "2023-10-26 19:50:07", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Gentner-D-R", "name": { "family": "Gentner", "given": "D. R." } }, { "id": "Ford-T-B", "name": { "family": "Ford", "given": "T. B." } }, { "id": "Guha-A", "name": { "family": "Guha", "given": "A." } }, { "id": "Boulanger-K", "name": { "family": "Boulanger", "given": "K." } }, { "id": "Brioude-J", "name": { "family": "Brioude", "given": "J." } }, { "id": "Angevine-W-M", "name": { "family": "Angevine", "given": "W. M." } }, { "id": "de-Gouw-J-A", "name": { "family": "de Gouw", "given": "J. A." }, "orcid": "0000-0002-0385-1826" }, { "id": "Warneke-C", "name": { "family": "Warneke", "given": "C." } }, { "id": "Gilman-J-B", "name": { "family": "Gilman", "given": "J. B." } }, { "id": "Ryerson-T-B", "name": { "family": "Ryerson", "given": "T. B." }, "orcid": "0000-0003-2800-7581" }, { "id": "Peischl-J", "name": { "family": "Peischl", "given": "J." }, "orcid": "0000-0002-9320-7101" }, { "id": "Meinardi-S", "name": { "family": "Meinardi", "given": "S." } }, { "id": "Blake-D-R", "name": { "family": "Blake", "given": "D. R." } }, { "id": "Atlas-E-L", "name": { "family": "Atlas", "given": "E." }, "orcid": "0000-0003-3847-5346" }, { "id": "Lonneman-W-A", "name": { "family": "Lonneman", "given": "W. A." } }, { "id": "Kleindienst-T-E", "name": { "family": "Kleindienst", "given": "T. E." }, "orcid": "0000-0002-3024-1564" }, { "id": "Beaver-M-R", "name": { "family": "Beaver", "given": "M. R." } }, { "id": "St-Clair-J-M", "name": { "family": "St. Clair", "given": "J. M." }, "orcid": "0000-0002-9367-5749" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" }, { "id": "VandenBoer-T-C", "name": { "family": "VandenBoer", "given": "T. C." } }, { "id": "Markovic-M-Z", "name": { "family": "Markovic", "given": "M. Z." } }, { "id": "Murphy-J-G", "name": { "family": "Murphy", "given": "J. G." } }, { "id": "Harley-R-A", "name": { "family": "Harley", "given": "R. A." } }, { "id": "Goldstein-A-H", "name": { "family": "Goldstein", "given": "A. H." }, "orcid": "0000-0003-4014-4896" } ] }, "title": "Emissions of organic carbon and methane from petroleum and dairy operations in California's San Joaquin Valley", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2014 Author(s). \nThis work is distributed\nunder the Creative Commons Attribution 3.0 License. \nPublished by Copernicus Publications on behalf of the European Geosciences Union. \n\nReceived: 10 September 2013. Published in Atmos. Chem. Phys. Discuss.: 31 October 2013. Revised: 28 March 2014. Accepted: 1 April 2014. Published: 21 May 2014. \n\nFor their support, we would like to acknowledge the California Air Resources Board (Contract 08-316), the National Oceanic and Atmospheric Administration (GRANT #NA10OAR4310104), and the U.C. Berkeley undergraduate chemistry summer research fellowship. We would also like to thank Joe Fisher and Jim Nyarady (CARB), Jason Surratt and Caitlin Rubitschun\n(U. North Carolina, Chapel Hill), and John Offenberg (US\nEPA) for their contributions and feedback. The US Environmental Protection Agency through its Office of Research and Development collaborated in the research described here. The manuscript has been subjected to external peer review and has been cleared for publication. Mention of trade names or commercial products does not constitute endorsement or recommendation for use.\nEdited by: A. Carlton\n\nPublished - acp-14-4955-2014.pdf
Supplemental Material - acp-14-4955-2014-supplement.pdf
", "abstract": "Petroleum and dairy operations are prominent sources of gas-phase organic compounds in California's San Joaquin Valley. It is essential to understand the emissions and air quality impacts of these relatively understudied sources, especially for oil/gas operations in light of increasing US production. Ground site measurements in Bakersfield and regional aircraft measurements of reactive gas-phase organic compounds and methane were part of the CalNex (California Research at the Nexus of Air Quality and Climate Change) project to determine the sources contributing to regional gas-phase organic carbon emissions. Using a combination of near-source and downwind data, we assess the composition and magnitude of emissions, and provide average source profiles. To examine the spatial distribution of emissions in the San Joaquin Valley, we developed a statistical modeling method using ground-based data and the FLEXPART-WRF transport and meteorological model. We present evidence for large sources of paraffinic hydrocarbons from petroleum operations and oxygenated compounds from dairy (and other cattle) operations. In addition to the small straight-chain alkanes typically associated with petroleum operations, we observed a wide range of branched and cyclic alkanes, most of which have limited previous in situ measurements or characterization in petroleum operation emissions. Observed dairy emissions were dominated by ethanol, methanol, acetic acid, and methane. Dairy operations were responsible for the vast majority of methane emissions in the San Joaquin Valley; observations of methane were well correlated with non-vehicular ethanol, and multiple assessments of the spatial distribution of emissions in the San Joaquin Valley highlight the dominance of dairy operations for methane emissions. The petroleum operations source profile was developed using the composition of non-methane hydrocarbons in unrefined natural gas associated with crude oil. The observed source profile is consistent with fugitive emissions of condensate during storage or processing of associated gas following extraction and methane separation. Aircraft observations of concentration hotspots near oil wells and dairies are consistent with the statistical source footprint determined via our FLEXPART-WRF-based modeling method and ground-based data. We quantitatively compared our observations at Bakersfield to the California Air Resources Board emission inventory and find consistency for relative emission rates of reactive organic gases between the aforementioned sources and motor vehicles in the region. We estimate that petroleum and dairy operations each comprised 22% of anthropogenic non-methane organic carbon at Bakersfield and were each responsible for 8\u201313% of potential precursors to ozone. Yet, their direct impacts as potential secondary organic aerosol (SOA) precursors were estimated to be minor for the source profiles observed in the San Joaquin Valley.", "date": "2014-05-21", "date_type": "published", "publication": "Atmospheric Chemistry and Physics", "volume": "14", "number": "10", "publisher": "European Geosciences Union", "pagerange": "4955-4978", "id_number": "CaltechAUTHORS:20140627-113643559", "issn": "1680-7316", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140627-113643559", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "California Air Resources Board", "grant_number": "08-316" }, { "agency": "National Oceanic and Atmospheric Administration (NOAA)", "grant_number": "NA10OAR4310104" }, { "agency": "U.C. Berkeley undergraduate chemistry summer research fellowship" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/acp-14-4955-2014", "primary_object": { "basename": "acp-14-4955-2014-supplement.pdf", "url": "https://authors.library.caltech.edu/records/zvm93-53n26/files/acp-14-4955-2014-supplement.pdf" }, "related_objects": [ { "basename": "acp-14-4955-2014.pdf", "url": "https://authors.library.caltech.edu/records/zvm93-53n26/files/acp-14-4955-2014.pdf" } ], "resource_type": "article", "pub_year": "2014", "author_list": "Gentner, D. R.; Ford, T. B.; et el." }, { "id": "https://authors.library.caltech.edu/records/ahyzy-15n58", "eprint_id": 46553, "eprint_status": "archive", "datestamp": "2023-08-22 12:42:47", "lastmod": "2023-10-26 19:50:04", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Rex-M", "name": { "family": "Rex", "given": "M." } }, { "id": "Wohltmann-I", "name": { "family": "Wohltmann", "given": "I." } }, { "id": "Ridder-T", "name": { "family": "Ridder", "given": "T." } }, { "id": "Lehmann-R", "name": { "family": "Lehmann", "given": "R." } }, { "id": "Rosenlof-K", "name": { "family": "Rosenlof", "given": "K." } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P." }, "orcid": "0000-0002-6126-3854" }, { "id": "Weisenstein-D-K", "name": { "family": "Weisenstein", "given": "D." } }, { "id": "Notholt-J", "name": { "family": "Notholt", "given": "J." } }, { "id": "Kr\u00fcger-K", "name": { "family": "Kr\u00fcger", "given": "K." } }, { "id": "Mohr-V", "name": { "family": "Mohr", "given": "V." } }, { "id": "Tegtmeier-S", "name": { "family": "Tegtmeier", "given": "S." } } ] }, "title": "A tropical West Pacific OH minimum and implications for stratospheric composition", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2014 Author(s). This work is distributed\nunder the Creative Commons Attribution 3.0 License. \nPublished by Copernicus Publications on behalf of the European Geosciences Union.\n\nReceived: 16 October 2013, Published in Atmos. Chem. Phys. Discuss.: 5 November 2013. Revised: 26 March 2014. Accepted: 27 March 2014. Published: 15 May 2014.\n\nWe thank two anonymous reviewers and in particular M. Manning for very useful comments on the original manuscript, which significantly improved the paper. We thank\nRu-Shan Gao (NOAA) for his contributions and sharing his data. This work was supported by the European Community within the SHIVA project (grant no. 226224) and the StratoClim project (grant no. 603557). TransBrom was financed by the BMBF (grant no. 03G0731A). Susan Tegtmeier and Viktoria Mohr were funded by the WGL project TransBrom. We thank ECMWF for providing ERA Interim data. \nEdited by: W. T. Sturges.\n\nPublished - acp-14-4827-2014.pdf
", "abstract": "Most of the short-lived biogenic and anthropogenic chemical species that are emitted into the atmosphere break down efficiently by reaction with OH and do not reach the stratosphere. Here we show the existence of a pronounced minimum in the tropospheric column of ozone over the West Pacific, the main source region for stratospheric air, and suggest a corresponding minimum of the tropospheric column of OH. This has the potential to amplify the impact of surface emissions on the stratospheric composition compared to the impact when assuming globally uniform OH conditions. Specifically, the role of emissions of biogenic halogenated species for the stratospheric halogen budget and the role of increasing emissions of SO_2 in Southeast Asia or from minor volcanic eruptions for the increasing stratospheric aerosol loading need to be reassessed in light of these findings. This is also important since climate change will further modify OH abundances and emissions of halogenated species. Our study is based on ozone sonde measurements carried out during the TransBrom cruise with the RV Sonne roughly along 140\u2013150\u00b0 E in October 2009 and corroborating ozone and OH measurements from satellites, aircraft campaigns and FTIR instruments. Model calculations with the GEOS-Chem Chemistry and Transport Model (CTM) and the ATLAS CTM are used to simulate the tropospheric OH distribution over the West Pacific and the transport pathways to the stratosphere. The potential effect of the OH minimum on species transported into the stratosphere is shown via modeling the transport and chemistry of CH_2Br_2 and SO_2.", "date": "2014-05-15", "date_type": "published", "publication": "Atmospheric Chemistry and Physics", "volume": "14", "number": "9", "publisher": "European Geosciences Union", "pagerange": "4827-4841", "id_number": "CaltechAUTHORS:20140627-110737071", "issn": "1680-7316", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140627-110737071", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "European Community", "grant_number": "226224" }, { "agency": "European Community", "grant_number": "603557" }, { "agency": "Bundesministerium f\u00fcr Bildung und Forschung (BMBF)", "grant_number": "03G0731A" }, { "agency": "WGL Project TransBrom" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/acp-14-4827-2014", "primary_object": { "basename": "acp-14-4827-2014.pdf", "url": "https://authors.library.caltech.edu/records/ahyzy-15n58/files/acp-14-4827-2014.pdf" }, "resource_type": "article", "pub_year": "2014", "author_list": "Rex, M.; Wohltmann, I.; et el." }, { "id": "https://authors.library.caltech.edu/records/y8k70-3wa87", "eprint_id": 46262, "eprint_status": "archive", "datestamp": "2023-08-22 12:32:17", "lastmod": "2023-10-26 19:37:56", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "St-Clair-J-M", "name": { "family": "St. Clair", "given": "J. M." }, "orcid": "0000-0002-9367-5749" }, { "id": "Spencer-K-M", "name": { "family": "Spencer", "given": "K. M." } }, { "id": "Beaver-M-R", "name": { "family": "Beaver", "given": "M. R." } }, { "id": "Crounse-J-D", "name": { "family": "Crounse", "given": "J. D." }, "orcid": "0000-0001-5443-729X" }, { "id": "Paulot-F", "name": { "family": "Paulot", "given": "F." }, "orcid": "0000-0001-7534-4922" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "Quantification of hydroxyacetone and glycolaldehyde using chemical ionization mass spectrometry", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2014 Author(s). This work is distributed\nunder the Creative Commons Attribution 3.0 License. \nPublished by Copernicus Publications on behalf of the European Geosciences Union.\n\nReceived: 26 July 2011 \u2013 Published in Atmos. Chem. Phys. Discuss.: 22 August 2011.\nRevised: 10 March 2014 \u2013 Accepted: 11 March 2014 \u2013 Published: 30 April 2014.\n\nG. S. Diskin and G. W. Sachse provided\nARCTAS-CARB water measurements and CO measurements.\nBEARPEX 2009 water measurements were provided by\nA. H. Goldstein. Isoprene and MBO measurements were provided\nby G. W. Schade. The authors wish to thank the ARCTAS-CARB\nscience team, the DC-8 crew, and the ARCTAS-CARB support\nteam. The authors also wish to thank the BEARPEX science team\nand the UC Blodgett Forest Research staff. The hydroxyacetone,\nglycolaldehyde, and acetic acid measurements and their interpretation\nwere made possible with the financial support of NASA (NAG:\nNNX-08AD29G) and the NSF (ATM-0934408).\n\nEdited by: V. F. McNeill\n\nPublished - acp-14-4251-2014.pdf
", "abstract": "Chemical ionization mass spectrometry (CIMS) enables online, rapid, in situ detection and quantification of hydroxyacetone and glycolaldehyde. Two different CIMS approaches are demonstrated employing the strengths of single quadrupole mass spectrometry and triple quadrupole (tandem) mass spectrometry. Both methods are generally capable of the measurement of hydroxyacetone, an analyte with known but minimal isobaric interferences. Tandem mass spectrometry provides direct separation of the isobaric compounds glycolaldehyde and acetic acid using distinct, collision-induced dissociation daughter ions. The single quadrupole CIMS measurement of glycolaldehyde was demonstrated during the ARCTAS-CARB (Arctic Research of the Composition of the Troposphere from Aircraft and Satellites - California Air Resources Board) 2008 campaign, while triple quadrupole CIMS measurements of glycolaldehyde and hydroxyacetone were demonstrated during the BEARPEX (Biosphere Effects on Aerosols and Photochemistry Experiment) 2009 campaign. Enhancement ratios of glycolaldehyde in ambient biomass-burning plumes are reported for the ARCTAS-CARB campaign. BEARPEX observations are compared to simple photochemical box model predictions of biogenic volatile organic compound oxidation at the site.", "date": "2014-04-30", "date_type": "published", "publication": "Atmospheric Chemistry and Physics", "volume": "14", "number": "8", "publisher": "European Geosciences Union", "pagerange": "4251-4262", "id_number": "CaltechAUTHORS:20140613-095234886", "issn": "1680-7316", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140613-095234886", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NAG: NNX-08AD29G" }, { "agency": "NSF", "grant_number": "ATM-0934408" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/acp-14-4251-2014", "primary_object": { "basename": "acp-14-4251-2014.pdf", "url": "https://authors.library.caltech.edu/records/y8k70-3wa87/files/acp-14-4251-2014.pdf" }, "resource_type": "article", "pub_year": "2014", "author_list": "St. Clair, J. M.; Spencer, K. M.; et el." }, { "id": "https://authors.library.caltech.edu/records/qrdbq-yt783", "eprint_id": 46005, "eprint_status": "archive", "datestamp": "2023-08-22 12:32:12", "lastmod": "2023-10-26 18:36:34", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Galli-A", "name": { "family": "Galli", "given": "A." } }, { "id": "Guerlet-S", "name": { "family": "Guerlet", "given": "S." } }, { "id": "Butz-A", "name": { "family": "Butz", "given": "A." }, "orcid": "0000-0003-0593-1608" }, { "id": "Aben-I", "name": { "family": "Aben", "given": "I." } }, { "id": "Suto-H", "name": { "family": "Suto", "given": "H." } }, { "id": "Kuze-A", "name": { "family": "Kuze", "given": "A." } }, { "id": "Deutscher-N-M", "name": { "family": "Deutscher", "given": "N. M." }, "orcid": "0000-0002-2906-2577" }, { "id": "Notholt-J", "name": { "family": "Notholt", "given": "J." } }, { "id": "Wunch-D", "name": { "family": "Wunch", "given": "D." }, "orcid": "0000-0002-4924-0377" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Griffith-D-W-T", "name": { "family": "Griffith", "given": "D. W. T." }, "orcid": "0000-0002-7986-1924" }, { "id": "Hasekamp-O", "name": { "family": "Hasekamp", "given": "O." } }, { "id": "Landgraf-J", "name": { "family": "Landgraf", "given": "J." }, "orcid": "0000-0002-6069-0598" } ] }, "title": "The impact of spectral resolution on satellite retrieval accuracy of CO_2 and CH_4", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 Author(s) 2014. This work is distributed under the Creative Commons Attribution 3.0 License. \n\nReceived: 15 November 2013; Published in Atmos. Meas. Tech. Discuss.: 4 December 2013; Revised: 26 February 2014; Accepted: 13 March 2014; Published: 29 April 2014.\n\nThe first author was supported by ESA under ESA contract number 4000105676/12/NL/AF. S. Guerlet acknowledges funding from ESA's Climate Change Initiative on greenhouse gases and the European Commission's Seventh Framework Programme under grant agreement 218793. A. Butz is supported by Deutsche Forschungsgemeinschaft (DFG) through the Emmy Noether Programme, grant BU2599/1-1 (RemoTeC).\nUS funding for TCCON comes from NASA's Terrestrial Ecology\nProgram, grant number NNX11AG01G, the Orbiting Carbon Observatory Program, the Atmospheric CO2 Observations from\nSpace (ACOS) Program and the DOE/ARM Program. The Darwin\nTCCON site was built at Caltech with funding from the OCO\nproject, and is operated by the University of Wollongong, with travel funds for maintenance and equipment costs funded by the OCO-2 project. We acknowledge funding to support Darwin and Wollongong from the Australian Research Council, Projects LE0668470, DP0879468, DP110103118 and LP0562346. The University of Bremen acknowledges financial support of the Bia\u0142ystok and Orl\u00e9ans TCCON sites from the Senate of Bremen and EU projects IMECC, GEOmon, InGOS, and ICOS-INWIRE, as well as maintenance and logistical work provided by AeroMeteo Service (Bia\u0142ystok) and the RAMCES team at LSCE (Gif-sur-Yvette, France) and additional operational funding from the National Institute for Environmental Studies. ECMWF ERA Interim analyses are\nprovided through http://data-portal.ecmwf.int/data/d/interimdaily/. TM4 modelled CH4 and CO concentration fields have been made available through J. F. Meirink, Royal Netherlands Meteorological Institute (KNMI).\nEdited by: A. Lambert\n\nPublished - amt-7-1105-2014.pdf
", "abstract": "The Fourier-transform spectrometer on board the Japanese GOSAT (Greenhouse gases Observing SATellite) satellite offers an excellent opportunity to study the impact of instrument resolution on retrieval accuracy of CO_2 and CH_4. This is relevant to further improve retrieval accuracy and to optimize the cost\u2013benefit ratio of future satellite missions for the remote sensing of greenhouse gases. To address this question, we degrade GOSAT measurements with a spectral resolution of \u2248 0.24 cm^(\u22121) step by step to a resolution of 1.5 cm^(\u22121). We examine the results by comparing relative differences at various resolutions, by referring the results to reference values from the Total Carbon Column Observing Network (TCCON), and by calculating and inverting synthetic spectra for which the true CO_2 and CH_4 columns are known. The main impacts of degrading the spectral resolution are reproduced for all approaches based on GOSAT measurements; pure forward model errors identified with simulated measurements are much smaller.\n\nFor GOSAT spectra, the most notable effect on CO_2 retrieval accuracy is the increase of the standard deviation of retrieval errors from 0.7 to 1.0% when the spectral resolution is reduced by a factor of six. The retrieval biases against atmospheric water abundance and air mass become stronger with decreasing resolution. The error scatter increase for CH_4 columns is less pronounced. The selective degradation of single spectral windows demonstrates that the retrieval accuracy of CO_2 and CH_4 is dominated by the spectral range where the absorption lines of the target molecule are located. For both GOSAT and synthetic measurements, retrieval accuracy decreases with lower spectral resolution for a given signal-to-noise ratio, suggesting increasing interference errors.", "date": "2014-04-29", "date_type": "published", "publication": "Atmospheric Measurement Techniques", "volume": "7", "number": "4", "publisher": "European Geosciences Union", "pagerange": "1105-1119", "id_number": "CaltechAUTHORS:20140530-105533786", "issn": "1867-8548", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140530-105533786", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "European Space Agency (ESA)", "grant_number": "4000105676/12/NL/AF" }, { "agency": "European Research Council (ERC)", "grant_number": "218793" }, { "agency": "Deutsche Forschungsgemeinschaft (DFG)", "grant_number": "BU2599/1-1" }, { "agency": "Australian Research Council", "grant_number": "LE0668470" }, { "agency": "Australian Research Council", "grant_number": "DP0879468" }, { "agency": "Australian Research Council", "grant_number": "DP110103118" }, { "agency": "Australian Research Council", "grant_number": "LP0562346" }, { "agency": "National Institute for Environmental Studies" }, { "agency": "NASA", "grant_number": "NNX11AG01G" }, { "agency": "Department of Energy (DOE)" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/amt-7-1105-2014", "primary_object": { "basename": "amt-7-1105-2014.pdf", "url": "https://authors.library.caltech.edu/records/qrdbq-yt783/files/amt-7-1105-2014.pdf" }, "resource_type": "article", "pub_year": "2014", "author_list": "Galli, A.; Guerlet, S.; et el." }, { "id": "https://authors.library.caltech.edu/records/f87qe-bng25", "eprint_id": 45958, "eprint_status": "archive", "datestamp": "2023-08-22 12:27:23", "lastmod": "2023-10-26 18:34:04", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Nguyen-Tran-B", "name": { "family": "Nguyen", "given": "T. B." } }, { "id": "Coggon-M-M", "name": { "family": "Coggon", "given": "M. M." }, "orcid": "0000-0002-5763-1925" }, { "id": "Bates-K-H", "name": { "family": "Bates", "given": "K. H." }, "orcid": "0000-0001-7544-9580" }, { "id": "Zhang-Xuan", "name": { "family": "Zhang", "given": "X." } }, { "id": "Schwantes-R-H", "name": { "family": "Schwantes", "given": "R. H." }, "orcid": "0000-0002-7095-3718" }, { "id": "Schilling-K-A", "name": { "family": "Schilling", "given": "K. A." } }, { "id": "Loza-C-L", "name": { "family": "Loza", "given": "C. L." } }, { "id": "Flagan-R-C", "name": { "family": "Flagan", "given": "R. C." }, "orcid": "0000-0001-5690-770X" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Seinfeld-J-H", "name": { "family": "Seinfeld", "given": "J. H." }, "orcid": "0000-0003-1344-4068" } ] }, "title": "Organic aerosol formation from the reactive uptake of isoprene epoxydiols (IEPOX) onto non-acidified inorganic seeds", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2014 Author(s). This work is distributed under the Creative Commons Attribution 3.0 License.\n\nReceived: 10 October 2013; Published in Atmos. Chem. Phys. Discuss.: 28 October 2013; Revised: 8 February 2014; Accepted: 18 February 2014; Published: 8 April 2014.\n\nThis research was supported by the National Science Foundation (NSF) grants AGS-1057183 and AGS-1240604. TBN acknowledges funding from the NSF Postdoctoral Research Fellowship program, award AGS-1331360, and from the Foster and Coco Stanback Postdoctoral Fellowship. We are grateful for research support provided by the Brian Stoltz Group\nat Caltech for the syntheses of the \u03b2-IEPOX isomers, with special acknowledgement to Dr. Nathan Bennett. We thank Dr. Nathan Dalleska, director of the Caltech Environmental Analysis Center (EAC), for his assistance with the UPLC/ESI-ToFMS analyses.\n\nPublished - acp-14-3497-2014.pdf
Supplemental Material - acp-14-3497-2014-supplement.pdf
", "abstract": "The reactive partitioning of cis and trans \u03b2-IEPOX was investigated on hydrated inorganic seed particles, without the addition of acids. No organic aerosol (OA) formation was observed on dry ammonium sulfate (AS); however, prompt and efficient OA growth was observed for the cis and trans \u03b2-IEPOX on AS seeds at liquid water contents of 40\u201375% of the total particle mass. OA formation from IEPOX is a kinetically limited process, thus the OA growth continues if there is a reservoir of gas-phase IEPOX. There appears to be no differences, within error, in the OA growth or composition attributable to the cis / trans isomeric structures. Reactive uptake of IEPOX onto hydrated AS seeds with added base (NaOH) also produced high OA loadings, suggesting the pH dependence for OA formation from IEPOX is weak for AS particles. No OA formation, after particle drying, was observed on seed particles where Na^+ was substituted for NH^(+)_(4). The Henry's Law partitioning of IEPOX was measured on NaCl particles (ionic strength ~9 M) to be 3 \u00d7 10^7 M atm^\u22121 (\u221250 / +100%). A small quantity of OA was produced when NH4+ was present in the particles, but the chloride (Cl-) anion was substituted for sulfate (SO^(2-)_(4)), possibly suggesting differences in nucleophilic strength of the anions. Online time-of-flight aerosol mass spectrometry and offline filter analysis provide evidence of oxygenated hydrocarbons, organosulfates, and amines in the particle organic composition. The results are consistent with weak correlations between IEPOX-derived OA and particle acidity or liquid water observed in field studies, as the chemical system is nucleophile-limited and not limited in water or catalyst activity.", "date": "2014-04-08", "date_type": "published", "publication": "Atmospheric Chemistry and Physics", "volume": "14", "number": "7", "publisher": "European Geosciences Union", "pagerange": "3497-3510", "id_number": "CaltechAUTHORS:20140529-084758310", "issn": "1680-7316", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140529-084758310", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "AGS-1057183" }, { "agency": "NSF", "grant_number": "AGS- 1240604" }, { "agency": "NSF Postdoctoral Fellowship", "grant_number": "AGS-1331360" }, { "agency": "Foster and Coco Stanback Postdoctoral Fellowship" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/acp-14-3497-2014", "primary_object": { "basename": "acp-14-3497-2014-supplement.pdf", "url": "https://authors.library.caltech.edu/records/f87qe-bng25/files/acp-14-3497-2014-supplement.pdf" }, "related_objects": [ { "basename": "acp-14-3497-2014.pdf", "url": "https://authors.library.caltech.edu/records/f87qe-bng25/files/acp-14-3497-2014.pdf" } ], "resource_type": "article", "pub_year": "2014", "author_list": "Nguyen, T. B.; Coggon, M. M.; et el." }, { "id": "https://authors.library.caltech.edu/records/xpays-9nb23", "eprint_id": 45923, "eprint_status": "archive", "datestamp": "2023-08-23 16:58:59", "lastmod": "2023-10-26 18:33:01", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Pusede-S-E", "name": { "family": "Pusede", "given": "S. E." } }, { "id": "Beaver-M-R", "name": { "family": "Beaver", "given": "M. R." } }, { "id": "St-Clair-J-M", "name": { "family": "St. Clair", "given": "J. M." }, "orcid": "0000-0002-9367-5749" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "On the temperature dependence of organic reactivity, nitrogen oxides, ozone production, and the impact of emission controls in San Joaquin Valley, California", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2014 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: 7 October 2013; Published in Atmos. Chem. Phys. Discuss.: 1 November 2013; Revised: 31 January 2014; Accepted: 12 February 2014;Published: 4 April 2014.\n\nThis work was funded by the California Air Resources Board (contract CARB 08-316) and by the National Aeronautics and Space Administration (grant NNX10AR36G). We are grateful to John Karlik, Rick Ramirez, and the entire University\nof California Kern County Extension for logistical support during the CalNex-SJV project. We thank David Parrish for useful comments on our manuscript. We acknowledge the California Air Resources Board and the San Joaquin Valley Unified Air Pollution Control District for the temperature and O3 data. The findings and discussions described in this paper are those of the authors and do not necessarily represent the views of our sponsors.\n\nPublished - acp-14-3373-2014.pdf
", "abstract": "The San Joaquin Valley (SJV) experiences some of the worst ozone air quality in the US, frequently exceeding the California 8 h standard of 70.4 ppb. To improve our understanding of trends in the number of ozone violations in the SJV, we analyze observed relationships between organic reactivity, nitrogen oxides (NO_x), and daily maximum temperature in the southern SJV using measurements made as part of California at the Nexus of Air Quality and Climate Change in 2010 (CalNex-SJV). We find the daytime speciated organic reactivity with respect to OH during CalNex-SJV has a temperature-independent portion with molecules typically associated with motor vehicles being the major component. At high temperatures, characteristic of days with high ozone, the largest portion of the total organic reactivity increases exponentially with temperature and is dominated by small, oxygenated organics and molecules that are unidentified. We use this simple temperature classification to consider changes in organic emissions over the last and next decade. With the CalNex-SJV observations as constraints, we examine the sensitivity of ozone production (PO_3) to future NO_x and organic reactivity controls. We find that PO_3 is NO_x-limited at all temperatures on weekends and on weekdays when daily maximum temperatures are greater than 29 \u00b0C. As a consequence, NO_x reductions are the most effective control option for reducing the frequency of future ozone violations in the southern SJV.", "date": "2014-04-04", "date_type": "published", "publication": "Atmospheric Chemistry and Physics", "volume": "14", "number": "7", "publisher": "European Geosciences Union", "pagerange": "3373-3395", "id_number": "CaltechAUTHORS:20140527-152856316", "issn": "1680-7316", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140527-152856316", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "California Air Resources Board", "grant_number": "CARB 08-316" }, { "agency": "NASA", "grant_number": "NNX10AR36G" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/acp-14-3373-2014", "primary_object": { "basename": "acp-14-3373-2014.pdf", "url": "https://authors.library.caltech.edu/records/xpays-9nb23/files/acp-14-3373-2014.pdf" }, "resource_type": "article", "pub_year": "2014", "author_list": "Pusede, S. E.; Beaver, M. R.; et el." }, { "id": "https://authors.library.caltech.edu/records/9wjrj-cdf78", "eprint_id": 45180, "eprint_status": "archive", "datestamp": "2023-08-22 11:55:41", "lastmod": "2023-10-26 17:37:06", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Lee-Lance", "name": { "family": "Lee", "given": "Lance" } }, { "id": "Teng-Alex-P", "name": { "family": "Teng", "given": "Alex P." } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Crounse-J-D", "name": { "family": "Crounse", "given": "John D." }, "orcid": "0000-0001-5443-729X" }, { "id": "Cohen-R-C", "name": { "family": "Cohen", "given": "Ronald C." }, "orcid": "0000-0001-6617-7691" } ] }, "title": "On Rates and Mechanisms of OH and O_3 Reactions with Isoprene-Derived Hydroxy Nitrates", "ispublished": "pub", "full_text_status": "public", "keywords": "Argonautes; cellular memory; epigenetics; piRNA", "note": "\u00a9 2014 American Chemical Society.\n\nPublished In Issue March 06, 2014; Article ASAP February 20, 2014; Received: October 31, 2013; Revised: February 07, 2014.\n\nThe authors declare no competing financial interest.\n\nThe authors acknowledge NSF AGS-1120076 (Berkeley), NSF\nAGS-1240604 (Caltech), and NASA NNX12AC06G (Caltech)\nfor their support of this research.\n\nSupplemental Material - jp4107603_si_001.pdf
", "abstract": "Eight distinct hydroxy nitrates are stable products of the first step in the atmospheric oxidation of isoprene by OH. The subsequent chemical fate of these molecules affects global and regional production of ozone and aerosol as well as the location of nitrogen deposition. We synthesized and purified 3 of the 8 isoprene hydroxy nitrate isomers: (E/Z)-2-methyl-4-nitrooxybut-2-ene-1-ol and 3-methyl-2-nitrooxybut-3-ene-1-ol. Oxidation of these molecules by OH and ozone was studied using both chemical ionization mass spectrometry and thermo-dissociation laser induced fluorescence. The OH reaction rate constants at 300 K measured relative to propene at 745 Torr are (1.1 \u00b1\n0.2) \u00d7 10^(\u221210) cm^3 molecule^(\u22121)s^(\u22121) for both the E and Z isomers and (4.2 \u00b1 0.7) \u00d7 10^(\u221211) cm^3 molecule^(\u22121)s^(\u22121) for the third isomer. The ozone reaction rate constants for (E/Z)-2-methyl-4-nitrooxybut-2-ene-1-ol are (2.7 \u00b1 0.5) \u00d7 10^(\u221217) and (2.9 \u00b1 0.5) \u00d7 10^(\u221217) cm^3 molecule^(\u22121)^s(\u22121), respectively. 3-Methyl-2-nitrooxybut-3-ene-1-ol reacts with ozone very\nslowly, within the range of (2.5\u22125) \u00d7 10^(\u221219) cm^3 molecule^(\u22121)s^(\u22121). Reaction pathways, product yields, and implications for atmospheric chemistry are discussed. A condensed mechanism suitable for use in atmospheric chemistry models is presented.", "date": "2014-03-06", "date_type": "published", "publication": "Journal of Physical Chemistry A", "volume": "118", "number": "9", "publisher": "American Chemical Society", "pagerange": "1622-1637", "id_number": "CaltechAUTHORS:20140424-090510301", "issn": "1089-5639", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140424-090510301", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "AGS-1120076" }, { "agency": "NSF", "grant_number": "AGS-1240604" }, { "agency": "NASA", "grant_number": "NNX12AC06G" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1021/jp4107603", "primary_object": { "basename": "jp4107603_si_001.pdf", "url": "https://authors.library.caltech.edu/records/9wjrj-cdf78/files/jp4107603_si_001.pdf" }, "resource_type": "article", "pub_year": "2014", "author_list": "Lee, Lance; Teng, Alex P.; et el." }, { "id": "https://authors.library.caltech.edu/records/mxypq-xt352", "eprint_id": 48282, "eprint_status": "archive", "datestamp": "2023-08-22 11:52:18", "lastmod": "2023-10-17 18:40:14", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Gao-R-S", "name": { "family": "Gao", "given": "R. S." } }, { "id": "Rosenlof-K-H", "name": { "family": "Rosenlof", "given": "K. H." } }, { "id": "Fahey-D-W", "name": { "family": "Fahey", "given": "D. W." } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Hintsa-E-J", "name": { "family": "Hintsa", "given": "E. J." } }, { "id": "Hanisco-T-F", "name": { "family": "Hanisco", "given": "T. F." }, "orcid": "0000-0001-9434-8507" } ] }, "title": "OH in the tropical upper troposphere and its relationships to solar radiation and reactive nitrogen", "ispublished": "pub", "full_text_status": "restricted", "keywords": "OH; In situ; Tropical upper troposphere; STRAT", "note": "\u00a9 2014 Springer Science+Business Media Dordrecht.\n\nReceived: 13 August 2013; Accepted: 23 March 2014; Published online: 12 April 2014.\n\nThis work was supported by the NOAA Atmospheric Composition and Climate Program and the NOAA Health of the Atmosphere Program, the NASA Radiation Sciences Program, and the NASA\nUpper Atmosphere Research Program. We would like to thank the NASA ER-2 program for making the mission possible. We thank M. Rex and L. L. Pan for insightful discussions.", "abstract": "In situ measurements of [OH], [HO_2] (square brackets denote species concentrations), and other chemical species were made in the tropical upper troposphere (TUT). [OH] showed a robust correlation with solar zenith angle. Beyond this dependence, however, [OH] did not correlate to its primary source, the product of [O_3] and [H_2O] ([O_3]\u2022[H_2O]), or its sink [NO_y]. This suggests that [OH] is heavily buffered in the TUT. One important exception to this result is found in regions with very low [O_3], [NO], and [NO_y]. Under these conditions, [OH] is highly suppressed, pointing to the critical role of NO in sustaining OH in the TUT and the possibility of low [OH] over the western Pacific warm pool due to strong marine convections bringing NO-poor air to the TUT. In contrast to [OH], [HO_x] ([OH] + [HO_2]) correlated reasonably well with [O_3]\u2022[H_2O]/[NO_y], suggesting that [O_3]\u2022[H_2O] and [NO_y] are the significant source and sink, respectively, of [HO_x].", "date": "2014-03", "date_type": "published", "publication": "Journal of Atmospheric Chemistry", "volume": "71", "number": "1", "publisher": "Springer", "pagerange": "55-64", "id_number": "CaltechAUTHORS:20140811-084352702", "issn": "0167-7764", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140811-084352702", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "National Oceanic and Atmospheric Administration (NOAA)" }, { "agency": "NASA" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1007/s10874-014-9280-2", "resource_type": "article", "pub_year": "2014", "author_list": "Gao, R. S.; Rosenlof, K. H.; et el." }, { "id": "https://authors.library.caltech.edu/records/4qs8k-tjn63", "eprint_id": 43756, "eprint_status": "archive", "datestamp": "2023-08-22 11:45:16", "lastmod": "2023-10-25 23:50:43", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Bates-K-H", "name": { "family": "Bates", "given": "Kelvin H." }, "orcid": "0000-0001-7544-9580" }, { "id": "Crounse-J-D", "name": { "family": "Crounse", "given": "John D." }, "orcid": "0000-0001-5443-729X" }, { "id": "St-Clair-J-M", "name": { "family": "St. Clair", "given": "Jason M." }, "orcid": "0000-0002-9367-5749" }, { "id": "Bennett-N-B", "name": { "family": "Bennett", "given": "Nathan B." } }, { "id": "Nguyen-Tran-B", "name": { "family": "Nguyen", "given": "Tran B." } }, { "id": "Seinfeld-J-H", "name": { "family": "Seinfeld", "given": "John H." }, "orcid": "0000-0003-1344-4068" }, { "id": "Stoltz-B-M", "name": { "family": "Stoltz", "given": "Brian M." }, "orcid": "0000-0001-9837-1528" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "Gas Phase Production and Loss of Isoprene Epoxydiols", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2014 American Chemical Society. \n \nReceived: November 1, 2013; Revised: January 28, 2014; Published: January 29, 2014. \n\nThe authors would like to thank Prof. Jason D. Surratt for correspondence regarding the synthesis of IEPOX and the National Science Foundation (AGS 1240604) for their support of this research.\n\nSupplemental Material - jp4107958_si_001.pdf
", "abstract": "Isoprene epoxydiols (IEPOX) form in high yields from the OH-initiated oxidation of isoprene under low-NO conditions. These compounds contribute significantly to secondary organic aerosol formation. Their gas-phase chemistry has, however, remained largely unexplored. In this study, we characterize the formation of IEPOX isomers from the oxidation of isoprene by OH. We find that cis-\u03b2- and trans-\u03b2-IEPOX are the dominant isomers produced, and that they are created in an approximate ratio of 1:2 from the low-NO oxidation of isoprene. Three isomers of IEPOX, including cis-\u03b2- and trans-\u03b2, were synthesized and oxidized by OH in environmental chambers under high- and low-NO conditions. We find that IEPOX reacts with OH at 299 K with rate coefficients of (0.84 \u00b1 0.07) \u00d7 10^(\u201311), (1.52 \u00b1 0.07) \u00d7 10^(\u201311), and (0.98 \u00b1 0.05) \u00d7 10^(\u201311) cm^3 molecule^(\u20131) s^(\u20131) for the \u03b41, cis-\u03b2, and trans-\u03b2 isomers. Finally, yields of the first-generation products of IEPOX + OH oxidation were measured, and a new mechanism of IEPOX oxidation is proposed here to account for the observed products. The substantial yield of glyoxal and methylglyoxal from IEPOX oxidation may help explain elevated levels of those compounds observed in low-NO environments with high isoprene emissions.", "date": "2014-02-20", "date_type": "published", "publication": "Journal of Physical Chemistry A", "volume": "118", "number": "7", "publisher": "American Chemical Society", "pagerange": "1237-1246", "id_number": "CaltechAUTHORS:20140210-145231305", "issn": "1089-5639", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140210-145231305", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "AGS-1240604" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1021/jp4107958", "primary_object": { "basename": "jp4107958_si_001.pdf", "url": "https://authors.library.caltech.edu/records/4qs8k-tjn63/files/jp4107958_si_001.pdf" }, "resource_type": "article", "pub_year": "2014", "author_list": "Bates, Kelvin H.; Crounse, John D.; et el." }, { "id": "https://authors.library.caltech.edu/records/mt1xh-dm477", "eprint_id": 44203, "eprint_status": "archive", "datestamp": "2023-08-22 11:07:55", "lastmod": "2023-10-26 00:17:16", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Hase-F", "name": { "family": "Hase", "given": "F." } }, { "id": "Drouin-B-J", "name": { "family": "Drouin", "given": "B. J." } }, { "id": "Roehl-C-M", "name": { "family": "Roehl", "given": "C. M." }, "orcid": "0000-0001-5383-8462" }, { "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": "Wunch-D", "name": { "family": "Wunch", "given": "D." }, "orcid": "0000-0002-4924-0377" }, { "id": "Blumenstock-T", "name": { "family": "Blumenstock", "given": "T." } }, { "id": "Desmet-F", "name": { "family": "Desmet", "given": "F." } }, { "id": "Feist-D-G", "name": { "family": "Feist", "given": "D. G." }, "orcid": "0000-0002-5890-6687" }, { "id": "Heikkinen-P", "name": { "family": "Heikkinen", "given": "P." } }, { "id": "De-Mazi\u00e8re-M", "name": { "family": "De Mazi\u00e8re", "given": "M." } }, { "id": "Rettinger-M", "name": { "family": "Rettinger", "given": "M." } }, { "id": "Robinson-J", "name": { "family": "Robinson", "given": "J." } }, { "id": "Schneider-M", "name": { "family": "Schneider", "given": "M." } }, { "id": "Sherlock-V", "name": { "family": "Sherlock", "given": "V." } }, { "id": "Sussmann-R", "name": { "family": "Sussmann", "given": "R." } }, { "id": "T\u00e9-Yao", "name": { "family": "T\u00e9", "given": "Y." } }, { "id": "Warneke-T", "name": { "family": "Warneke", "given": "T." }, "orcid": "0000-0001-5185-3415" }, { "id": "Weinzierl-C", "name": { "family": "Weinzierl", "given": "C." } } ] }, "title": "Calibration of sealed HCl cells used for TCCON instrumental line shape monitoring", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2013 Author(s). This work is distributed under the Creative Commons Attribution 3.0 License. \n\nPublished by Copernicus Publications on behalf of the European Geosciences Union. Received: 17 July 2013. Published in Atmos. Meas. Tech. Discuss.: 5 August 2013. Revised: 8 November 2013. Accepted: 12 November 2013. Published: 16 December 2013. \n\nWe would like to thank the head of the workshop at KIT IMK-ASF, A. Streili, for his exceeding commitment with the construction of the 40 cm cell bodies. We acknowledge support by the European integrating activity project InGOS (www.ingos-infrastructure.eu) for performing this study. BIRA thanks the Belgian Federal Science Policy for support through the AGACC-II project. The LPMAA is grateful to the French\nINSU LEFE programme for supporting the TCCON-Paris project.\nPart of this work was performed at the Jet Propulsion Laboratory, California Institute of Technology, under contract with NASA. We acknowledge support by Deutsche Forschungsgemeinschaft and Open Access Publishing Fund of the Karlsruhe Institute of Technology. The service charges for this open access publication have been covered by a Research Centre of the Helmholtz Association.\nEdited by: D. Griffith\n\nPublished - amt-6-3527-2013.pdf
", "abstract": "The TCCON (Total Carbon Column Observing\nNetwork) FTIR (Fourier transform infrared) network\nprovides highly accurate observations of greenhouse gas\ncolumn-averaged dry-air mole fractions. As an important\ncomponent of TCCON quality assurance, sealed cells filled\nwith approximately 5 mbar of HCl are used for instrumental\nline shape (ILS) monitoring at all TCCON sites. Here,\nwe introduce a calibration procedure for the HCl cells which\nemploys a refillable, pressure-monitored reference cell filled\nwith C_2H_2. Using this method, we identify variations of HCl\npurity between the TCCON cells as a non-negligible disturbance.\nThe new calibration procedure introduced here assigns\neffective pressure values to each individual cell to account\nfor additional broadening of the HCl lines. This approach\nwill improve the consistency of the network by significantly\nreducing possible station-to-station biases due to\ninconsistent ILS results from different HCl cells. We demonstrate\nthat the proposed method is accurate enough to turn the\nILS uncertainty into an error source of secondary importance\nfrom the viewpoint of network consistency.", "date": "2013-12-16", "date_type": "published", "publication": "Atmospheric Measurement Techniques", "volume": "6", "number": "12", "publisher": "European Geosciences Union", "pagerange": "3527-3537", "id_number": "CaltechAUTHORS:20140310-074115950", "issn": "1867-1381", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140310-074115950", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "European integrating activity project InGOS" }, { "agency": "Belgian Federal Science Policy Office (BELSPO)" }, { "agency": "Institut national des sciences de l'Univers (INSU)" }, { "agency": "NASA/JPL/Caltech" }, { "agency": "Deutsche Forschungsgemeinschaft (DFG)" }, { "agency": "Karlsruhe Institute of Technology Open Access Publishing Fund" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/amt-6-3527-2013", "primary_object": { "basename": "amt-6-3527-2013.pdf", "url": "https://authors.library.caltech.edu/records/mt1xh-dm477/files/amt-6-3527-2013.pdf" }, "resource_type": "article", "pub_year": "2013", "author_list": "Hase, F.; Drouin, B. J.; et el." }, { "id": "https://authors.library.caltech.edu/records/m30qa-2sn31", "eprint_id": 42636, "eprint_status": "archive", "datestamp": "2023-08-22 10:37:37", "lastmod": "2023-10-25 16:58:01", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Crounse-J-D", "name": { "family": "Crounse", "given": "John D." }, "orcid": "0000-0001-5443-729X" }, { "id": "Nielsen-L-B", "name": { "family": "Nielsen", "given": "Lasse B." } }, { "id": "J\u00f8rgensen-S", "name": { "family": "J\u00f8rgensen", "given": "Solvejg" } }, { "id": "Kjaergaard-H-G", "name": { "family": "Kjaergaard", "given": "Henrik G." }, "orcid": "0000-0002-7275-8297" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "Autoxidation of Organic Compounds in the Atmosphere", "ispublished": "pub", "full_text_status": "public", "keywords": "Environmental and Atmospheric Chemistry, Aerosol Processes, Geochemistry, and Astrochemistry", "note": "\u00a9 2013 American Chemical Society.\n\nReceived: September 6, 2013; Accepted: September 30, 2013; Published: September 30, 2013.\n\nThe authors thank NASA (NNX12AC06G) and NSF (AGS-1240604), the Danish Council for Independent Research - Natural Sciences, and the Danish Center for Scientific Computing (DCSC) for their support of this research.\n\nAdditional information on the instrumental calibration, timeline of 3-PN oxidation products, RO\u2082 H-shift barriers as a function of the number of atoms in the cyclic transition state, stereoselectivity of the RO\u2082 H-shift reactions, hydrogen\nabstraction in 3-pentanone oxidation by OH, and theoretical calculations for additional RO\u2082 H-shift reactions.\n\nSupplemental Material - jz4019207_si_001.pdf
", "abstract": "We present a hypothesis that autoxidation (inter- and intramolecular hydrogen abstraction by peroxy radicals) plays an important role in the oxidation of organic compounds in the atmosphere, particularly organic matter associated with aerosol. In the laboratory, we determine the rate of this process at room temperature for a model system, 3-pentanone. We employ ab initio calculations to investigate H-shifts within a broader group of substituted organic compounds. We show that the rate of abstraction of hydrogen by peroxy radicals is largely determined by the thermochemistry of the nascent alkyl radicals and thus is highly influenced by neighboring substituents. As a result, autoxidation rates increase rapidly as oxygen-containing functional groups (carbonyl, hydroxy, and hydroperoxy) are added to organic compounds. This mechanism is consistent with formation of the multifunctional hydroperoxides and carbonyls often found in atmospheric aerosol particles.", "date": "2013-10-17", "date_type": "published", "publication": "Journal of Physical Chemistry Letters", "volume": "4", "number": "20", "publisher": "American Chemical Society", "pagerange": "3513-3520", "id_number": "CaltechAUTHORS:20131121-161549474", "issn": "1948-7185", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20131121-161549474", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NNX12AC06G" }, { "agency": "NSF", "grant_number": "AGS-1240604" }, { "agency": "Danish Council for Independent Research - Natural Sciences" }, { "agency": "Danish Center for Scientific Computing (DCSC)" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1021/jz4019207", "primary_object": { "basename": "jz4019207_si_001.pdf", "url": "https://authors.library.caltech.edu/records/m30qa-2sn31/files/jz4019207_si_001.pdf" }, "resource_type": "article", "pub_year": "2013", "author_list": "Crounse, John D.; Nielsen, Lasse B.; et el." }, { "id": "https://authors.library.caltech.edu/records/j9nyx-g1593", "eprint_id": 44353, "eprint_status": "archive", "datestamp": "2023-08-22 10:37:28", "lastmod": "2023-10-26 00:24:57", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Mao-Jingqiu", "name": { "family": "Mao", "given": "Jingqiu" } }, { "id": "Paulot-Fabien", "name": { "family": "Paulot", "given": "Fabien" }, "orcid": "0000-0001-7534-4922" }, { "id": "Jacob-D-J", "name": { "family": "Jacob", "given": "Daniel J." }, "orcid": "0000-0002-6373-3100" }, { "id": "Cohen-R-C", "name": { "family": "Cohen", "given": "Ronald C." }, "orcid": "0000-0001-6617-7691" }, { "id": "Crounse-J-D", "name": { "family": "Crounse", "given": "John D." }, "orcid": "0000-0001-5443-729X" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Keller-C-A-ENV", "name": { "family": "Keller", "given": "Christoph A." } }, { "id": "Hudman-R-C", "name": { "family": "Hudman", "given": "Rynda C." } }, { "id": "Barkley-M-P", "name": { "family": "Barkley", "given": "Michael P." } }, { "id": "Horowitz-L-W", "name": { "family": "Horowitz", "given": "Larry W." } } ] }, "title": "Ozone and organic nitrates over the eastern United States: Sensitivity to isoprene chemistry", "ispublished": "pub", "full_text_status": "public", "keywords": "ozone; organic nitrates; isoprene chemistry; photooxidation; nitrogen export; nighttime chemistry", "note": "\u00a9 2013 American Geophysical Union.\n\nReceived 17 May 2013; revised 30 July 2013; accepted 6 September 2013; published 1 October 2013.\n\nWe thank the ICARTT science team for using their measurements. We thank Songmiao Fan and Vaishali Naik at GFDL for careful review. We also thank Ellie Browne (MIT), Havala Pye (EPA), Wendy Goliff (UC Riverside), Eloise Marais (Harvard), Katherine Travis (Harvard), Emily Fischer (Harvard), Mathew Evans (U of York), and Arlene Fiore (Columbia University) for helpful discussions. We also thank\nChristopher Holmes (UC Irvine) and Jenny Fisher (U of Wollongong) for help with IDL. J.M. and L.W.H. acknowledge the NOAA Climate Program Office's grant NA13OAR4310071. F.P was supported by Harvard University Center for the Environment Fellowship. Work at Harvard was supported by the\nNASA Atmospheric Chemistry Modeling and Analysis Program.\n\nPublished - jgrd50817.pdf
Supplemental Material - jgrd50817-sup-0001-isoprene_draft10_suppl.docx
Supplemental Material - jgrd50817-sup-0002-readme.txt
", "abstract": "We implement a new isoprene oxidation mechanism in a global 3-D chemical transport model (GEOS-Chem). Model results are evaluated with observations for ozone, isoprene oxidation products, and related species from the International Consortium for Atmospheric Research on Transport and Transformation aircraft campaign over the eastern United States in summer 2004. The model achieves an unbiased simulation of ozone in the boundary layer and the free troposphere, reflecting canceling effects from recent model updates for isoprene chemistry, bromine chemistry, and HO2 loss to aerosols. Simulation of the ozone-CO correlation is improved relative to previous versions of the model, and this is attributed to a lower and reversible yield of isoprene nitrates, increasing the ozone production efficiency per unit of nitrogen oxides (NO_x\u2009\u2261\u2009NO\u2009+\u2009NO_2). The model successfully reproduces the observed concentrations of organic nitrates (\u2211ANs) and their correlations with HCHO and ozone. \u2211ANs in the model is principally composed of secondary isoprene nitrates, including a major contribution from nighttime isoprene oxidation. The correlations of \u2211ANs with HCHO and ozone then provide sensitive tests of isoprene chemistry and argue in particular against a fast isomerization channel for isoprene peroxy radicals. \u2211ANs can provide an important reservoir for exporting NO_x from the U.S. boundary layer. We find that the dependence of surface ozone on isoprene emission is positive throughout the U.S., even if NO_x emissions are reduced by a factor of 4. Previous models showed negative dependences that we attribute to erroneous titration of OH by isoprene.", "date": "2013-10-16", "date_type": "published", "publication": "Journal of Geophysical Research. Atmospheres", "volume": "118", "number": "19", "publisher": "American Geophysical Union", "pagerange": "11256-11268", "id_number": "CaltechAUTHORS:20140317-111859201", "issn": "2169-897X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140317-111859201", "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": "NA13OAR4310071" }, { "agency": "Harvard University" }, { "agency": "NASA" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1002/jgrd.50817", "primary_object": { "basename": "jgrd50817-sup-0001-isoprene_draft10_suppl.docx", "url": "https://authors.library.caltech.edu/records/j9nyx-g1593/files/jgrd50817-sup-0001-isoprene_draft10_suppl.docx" }, "related_objects": [ { "basename": "jgrd50817-sup-0002-readme.txt", "url": "https://authors.library.caltech.edu/records/j9nyx-g1593/files/jgrd50817-sup-0002-readme.txt" }, { "basename": "jgrd50817.pdf", "url": "https://authors.library.caltech.edu/records/j9nyx-g1593/files/jgrd50817.pdf" } ], "resource_type": "article", "pub_year": "2013", "author_list": "Mao, Jingqiu; Paulot, Fabien; et el." }, { "id": "https://authors.library.caltech.edu/records/qeh25-7tk97", "eprint_id": 42824, "eprint_status": "archive", "datestamp": "2023-08-22 10:37:07", "lastmod": "2023-10-25 23:04:08", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Worton-D-R", "name": { "family": "Worton", "given": "David R." } }, { "id": "Beaver-M-R", "name": { "family": "Beaver", "given": "Melinda" } }, { "id": "St-Clair-J-M", "name": { "family": "St. Clair", "given": "Jason M." }, "orcid": "0000-0002-9367-5749" }, { "id": "Crounse-J-D", "name": { "family": "Crounse", "given": "John" }, "orcid": "0000-0001-5443-729X" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul" }, "orcid": "0000-0002-6126-3854" }, { "id": "Seinfeld-J-H", "name": { "family": "Seinfeld", "given": "John H." }, "orcid": "0000-0003-1344-4068" } ] }, "title": "Observational Insights into Aerosol Formation from Isoprene", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2013 American Chemical Society. Received: March 12, 2013.\nRevised: August 1, 2013. Accepted: September 4, 2013.\nPublished: September 4, 2013. Funding for UCB was provided by the National Science Foundation (NSF, Grants ATM-0922562 and ATM-0639847). DKF, KSD, MJC and JLJ were supported by NSF ATM-0919189. JBG and JDG were partially supported by NSF ATM-0516610. GMW acknowledges support from NASA Earth\nSystems Science Fellowship NNG-05GP64H and U.S.-EPA\nSTAR Fellowship (FP-91698901). MRB, JMC, JC, and POW\nwere supported by NSF ATM-0934408 and ATM-0934345.\nAnalyses at the University of Aarhus were partially funded by the NSF US-NORDIC BSOA workshop program. The authors\nacknowledge Sierra Pacific Industries for the use of their land and the Blodgett Forest Research Station for cooperation in facilitating this research. The authors thank S. S. Cliff (University of California, Davis) for the loan of the high volume filter sampler, N. C. Bouvier-Brown (Loyola Marymount University, Los Angeles) for assistance with filter collection, J. Murphy (University of Toronto) for initial discussions about the E-AIM model, N. Eddingsaas (Caltech) for providing the BEPOX-derived\norganosulfate standard, D. Covert (University of\nWashington) for providing the SMPS measurements in 2009\nand M. Chan and K. Schilling (Caltech) for their assistance with filter extractions and UPLC/ESI-HR-TOFMS analyses. The authors declare no competing financial interest.\n\nSupplemental Material - es4011064_si_001.pdf
", "abstract": "Atmospheric photooxidation of isoprene is an important source of secondary organic aerosol (SOA) and there is increasing evidence that anthropogenic oxidant emissions can enhance this SOA formation. In this work, we use ambient observations of organosulfates formed from isoprene epoxydiols (IEPOX) and methacrylic acid epoxide (MAE) and a broad suite of chemical measurements to investigate the relative importance of nitrogen oxide (NO/NO_2) and hydroperoxyl (HO_2) SOA formation pathways from isoprene at a forested site in California. In contrast to IEPOX, the calculated production rate of MAE was observed to be independent of temperature. This is the result of the very fast thermolysis of MPAN at high temperatures that affects the distribution of the MPAN reservoir (MPAN / MPA radical) reducing the fraction that can react with OH to form MAE and subsequently SOA (F_(MAE formation)). The strong temperature dependence of F_(MAE formation) helps to explain our observations of similar concentrations of IEPOX-derived organosulfates (IEPOX-OS;~1 ng m^(\u20133)) and MAE-derived organosulfates (MAE-OS;~1 ng m^(\u20133)) under cooler conditions (lower isoprene concentrations) and much higher IEPOX-OS (~20 ng m^(\u20133)) relative to MAE-OS (<0.0005 ng m^(\u20133)) at higher temperatures (higher isoprene concentrations). A kinetic model of IEPOX and MAE loss showed that MAE forms 10\u2212100 times more ring-opening products than IEPOX and that both are strongly dependent on aerosol water content when aerosol pH is constant. However, the higher fraction of MAE ring opening products does not compensate for the lower MAE production under warmer conditions (higher isoprene concentrations) resulting in lower formation of MAE-derived products relative to IEPOX at the surface. In regions of high NO_x, high isoprene emissions and strong vertical mixing the slower MPAN thermolysis rate aloft could increase the fraction of MPAN that forms MAE resulting in a vertically varying isoprene SOA source.", "date": "2013-10-15", "date_type": "published", "publication": "Environmental Science and Technology", "volume": "47", "number": "20", "publisher": "American Chemical Society", "pagerange": "11403-11413", "id_number": "CaltechAUTHORS:20131204-104912735", "issn": "0013-936X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20131204-104912735", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "ATM-0922562" }, { "agency": "NSF", "grant_number": "ATM-0639847" }, { "agency": "NSF", "grant_number": "ATM-0919189" }, { "agency": "NSF", "grant_number": "ATM-0516610" }, { "agency": "NASA", "grant_number": "NNG-05GP64H" }, { "agency": "Environmental Protection Agency (EPA)", "grant_number": "FP-91698901" }, { "agency": "NSF", "grant_number": "ATM-0934408" }, { "agency": "NSF", "grant_number": "ATM-0934345" }, { "agency": "NSF US-NORDIC BSOA workshop program" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1021/es4011064", "primary_object": { "basename": "es4011064_si_001.pdf", "url": "https://authors.library.caltech.edu/records/qeh25-7tk97/files/es4011064_si_001.pdf" }, "resource_type": "article", "pub_year": "2013", "author_list": "Worton, David R.; Beaver, Melinda; et el." }, { "id": "https://authors.library.caltech.edu/records/q728n-cyy35", "eprint_id": 103567, "eprint_status": "archive", "datestamp": "2023-08-22 10:23:53", "lastmod": "2023-10-20 16:30:07", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Wunch-D", "name": { "family": "Wunch", "given": "D." }, "orcid": "0000-0002-4924-0377" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Messerschmidt-J", "name": { "family": "Messerschmidt", "given": "J." } }, { "id": "Parazoo-N-C", "name": { "family": "Parazoo", "given": "N. C." }, "orcid": "0000-0002-4424-7780" }, { "id": "Toon-G-C", "name": { "family": "Toon", "given": "G. C." }, "orcid": "0000-0003-4174-7541" }, { "id": "Deutscher-N-M", "name": { "family": "Deutscher", "given": "N. M." }, "orcid": "0000-0002-2906-2577" }, { "id": "Keppel-Aleks-G", "name": { "family": "Keppel-Aleks", "given": "G." } }, { "id": "Roehl-C-M", "name": { "family": "Roehl", "given": "C. M." }, "orcid": "0000-0001-5383-8462" }, { "id": "Randerson-J-T", "name": { "family": "Randerson", "given": "J. T." }, "orcid": "0000-0001-6559-7387" }, { "id": "Warneke-T", "name": { "family": "Warneke", "given": "T." }, "orcid": "0000-0001-5185-3415" }, { "id": "Notholt-J", "name": { "family": "Notholt", "given": "J." } } ] }, "title": "The covariation of Northern Hemisphere summertime CO\u2082 with surface temperature in boreal regions", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 Author(s) 2013. This work is distributed under the Creative Commons Attribution 3.0 License. \n\nReceived: 12 Mar 2013 \u2013 Discussion started: 19 Apr 2013 \u2013 Revised: 26 Jul 2013 \u2013 Accepted: 12 Aug 2013 \u2013 Published: 26 Sep 2013. \n\nThe authors would like to thank Prof. Peter Rayner and an anonymous reviewer for helpful comments that substantially improved this paper. CarbonTracker 2011 results were provided by NOAA ESRL, Boulder, Colorado, USA, from the website at http://carbontracker.noaa.gov. US funding for TCCON comes from NASA's Carbon Cycle Program, grant number NNX11AG01G, the Orbiting Carbon Observatory Program, and the DOE/ARM Program. We acknowledge financial support of the Bia\u0142ystok TCCON site from the Senate of Bremen and EU projects IMECC and GEOmon as well as maintenance and logistical work provided by AeroMeteo Service. P. O. Wennberg and J. T. Randerson receive support from NASA's Carbon Cycle Science program (NNX10AT83G). The GOSAT X_(CO\u2082) data were obtained from the Atmospheric CO\u2082 Observations from Space (ACOS) project. We thank the three Japanese parties (NIES, JAXA, MOE) for making the GOSAT spectra available to the scientific community. N. C. Parazoo carried out the research at the University of California Los Angeles and the Jet Propulsion Laboratory, and acknowledges support from NASA ROSES NNH09ZDA001N-ACOS. Part of this work was performed at the Jet Propulsion Laboratory, California Institute of Technology, under contract with NASA. Self-calibrated PDSI data with Penman\u2013Monteith PE were downloaded from\nhttp://www.cgd.ucar.edu/cas/catalog/climind/pdsi.html. \n\nEdited by: I. Aben.\n\nPublished - acp-13-9447-2013.pdf
", "abstract": "We observe significant interannual variability in the strength of the seasonal cycle drawdown in northern midlatitudes from measurements of CO\u2082 made by the Total Carbon Column Observing Network (TCCON) and the Greenhouse Gases Observing Satellite (GOSAT). This variability correlates with surface temperature in the boreal regions. Using TCCON measurements, we find that the slope of the relationship between the X_(CO\u2082) seasonal cycle minima and boreal surface temperature is 1.2 \u00b1 0.7 ppm K\u207b\u00b9. Assimilations from CarbonTracker 2011 and CO\u2082 simulations using the Simple Biosphere exchange Model (SiB) transported by GEOS-Chem underestimate this covariation. Both atmospheric transport and biospheric activity contribute to the observed covariation.", "date": "2013-09-26", "date_type": "published", "publication": "Atmospheric Chemistry and Physics", "volume": "13", "number": "18", "publisher": "European Geosciences Union", "pagerange": "9447-9459", "id_number": "CaltechAUTHORS:20200529-093434827", "issn": "1680-7324", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200529-093434827", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NNX11AG01G" }, { "agency": "Department of Energy (DOE)" }, { "agency": "Senate of Bremen" }, { "agency": "European Union" }, { "agency": "NASA", "grant_number": "NNX10AT83G" }, { "agency": "NASA", "grant_number": "NNH09ZDA001N-ACOS" }, { "agency": "NASA/JPL/Caltech" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/acp-13-9447-2013", "primary_object": { "basename": "acp-13-9447-2013.pdf", "url": "https://authors.library.caltech.edu/records/q728n-cyy35/files/acp-13-9447-2013.pdf" }, "resource_type": "article", "pub_year": "2013", "author_list": "Wunch, D.; Wennberg, P. O.; et el." }, { "id": "https://authors.library.caltech.edu/records/tsv99-sn952", "eprint_id": 41485, "eprint_status": "archive", "datestamp": "2023-08-19 21:08:15", "lastmod": "2023-10-24 23:46:43", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Yee-Lindsay-D", "name": { "family": "Yee", "given": "L. D." }, "orcid": "0000-0001-8965-9319" }, { "id": "Kautzman-K-E", "name": { "family": "Kautzman", "given": "K. E." } }, { "id": "Loza-Christine-L", "name": { "family": "Loza", "given": "C. L." } }, { "id": "Schilling-Katherine-A", "name": { "family": "Schilling", "given": "K. A." } }, { "id": "Coggon-Matthew-M", "name": { "family": "Coggon", "given": "M. M." }, "orcid": "0000-0002-5763-1925" }, { "id": "Chhabra-Puneet-S", "name": { "family": "Chhabra", "given": "P. S." } }, { "id": "Chan-Man-Nin", "name": { "family": "Chan", "given": "M. N." }, "orcid": "0000-0002-2384-2695" }, { "id": "Chan-Arthur-W-H", "name": { "family": "Chan", "given": "A. W. H." }, "orcid": "0000-0001-7392-4237" }, { "id": "Hersey-Scott-P", "name": { "family": "Hersey", "given": "S. P." } }, { "id": "Crounse-John-D", "name": { "family": "Crounse", "given": "J. D." }, "orcid": "0000-0001-5443-729X" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Flagan-R-C", "name": { "family": "Flagan", "given": "R. C." }, "orcid": "0000-0001-5690-770X" }, { "id": "Seinfeld-J-H", "name": { "family": "Seinfeld", "given": "J. H." }, "orcid": "0000-0003-1344-4068" } ] }, "title": "Secondary organic aerosol formation from biomass burning intermediates: phenol and methoxyphenols", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 Author(s) 2013. 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: 20 January 2013; Published in Atmos. Chem. Phys. Discuss.: 6 February 2013 Revised: 13 June 2013; Accepted: 20 June 2013; Published: 21 August 2013.\n\nThis work was supported by the US Department of Energy grants DE-FG02-05ER63983 and DE-SC 0006626 and US Environmental Protection Agency (EPA) STAR Research Agreement No. RD-833749.\n\nPublished - acp-13-8019-2013.pdf
", "abstract": "The formation of secondary organic aerosol from oxidation of phenol, guaiacol (2-methoxyphenol), and syringol (2,6-dimethoxyphenol), major components of biomass burning, is described. Photooxidation experiments were conducted in the Caltech laboratory chambers under low-NO\u2093 (< 10 ppb) conditions using H\u2082O\u2082 as the OH source. Secondary organic aerosol (SOA) yields (ratio of mass of SOA formed to mass of primary organic reacted) greater than 25% are observed. Aerosol growth is rapid and linear with the primary organic conversion, consistent with the formation of essentially non-volatile products. Gas- and aerosol-phase oxidation products from the guaiacol system provide insight into the chemical mechanisms responsible for SOA formation. Syringol SOA yields are lower than those of phenol and guaiacol, likely due to novel methoxy group chemistry that leads to early fragmentation in the gas-phase photooxidation. Atomic oxygen to carbon (O : C) ratios calculated from high-resolution-time-of-flight Aerodyne Aerosol Mass Spectrometer (HR-ToF-AMS) measurements of the SOA in all three systems are ~ 0.9, which represent among the highest such ratios achieved in laboratory chamber experiments and are similar to that of aged atmospheric organic aerosol. The global contribution of SOA from intermediate volatility and semivolatile organic compounds has been shown to be substantial (Pye and Seinfeld, 2010). An approach to representing SOA formation from biomass burning emissions in atmospheric models could involve one or more surrogate species for which aerosol formation under well-controlled conditions has been quantified. The present work provides data for such an approach.", "date": "2013-08-21", "date_type": "published", "publication": "Atmospheric Chemistry and Physics", "volume": "13", "number": "16", "publisher": "European Geosciences Union", "pagerange": "8019-8043", "id_number": "CaltechAUTHORS:20130923-142910735", "issn": "1680-7316", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20130923-142910735", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-FG02-05ER63983" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC 0006626" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/acp-13-8019-2013", "primary_object": { "basename": "acp-13-8019-2013.pdf", "url": "https://authors.library.caltech.edu/records/tsv99-sn952/files/acp-13-8019-2013.pdf" }, "resource_type": "article", "pub_year": "2013", "author_list": "Yee, L. D.; Kautzman, K. E.; et el." }, { "id": "https://authors.library.caltech.edu/records/e0myd-zgf59", "eprint_id": 41027, "eprint_status": "archive", "datestamp": "2023-08-22 10:04:07", "lastmod": "2023-10-24 23:23:44", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Kjaergaard-H-G", "name": { "family": "Kjaergaard", "given": "Henrik G." }, "orcid": "0000-0002-7275-8297" }, { "id": "Kurt\u00e9n-T", "name": { "family": "Kurt\u00e9n", "given": "Theo" }, "orcid": "0000-0002-6416-4931" }, { "id": "Nielsen-L-B", "name": { "family": "Nielsen", "given": "Lasse B." } }, { "id": "J\u00f8rgensen-S", "name": { "family": "J\u00f8rgensen", "given": "Solvejg" } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "Criegee Intermediates React with Ozone", "ispublished": "pub", "full_text_status": "public", "keywords": "Environmental and Atmospheric Chemistry, Aerosol Processes, Geochemistry, and Astrochemistry", "note": "\u00a9 2013 American Chemical Society. \n\nReceived: June 11, 2013; Accepted: July 18, 2013; Published: July 18, 2013. \n\nWe are grateful to Rasmus Faber and Sten Rettrup for helpful discussions. We thank The Danish Council for Independent Research - Natural Sciences, NASA (NNX08AD29G), and the NSF (ATM-0934408) for funding and the Danish Center for Scientific Computing (DCSC) and CSC Finland for computer resources.\n\nSupplemental Material - jz401205m_si_001.pdf
", "abstract": "We have investigated the reaction of the one-carbon stabilized Criegee intermediate (H_2COO, formaldehyde oxide) with ozone, theoretically, using high level coupled cluster ab initio methods. Key to the reactivity of the Criegee intermediate with ozone is the strongly exothermic formation of an intermediate consisting of five oxygen and one carbon atoms (H_2CO_5) in a six-membered ring structure. This intermediate proceeds via a spin-allowed route over two transition states with low energy barriers to form molecular oxygen and formaldehyde. The reaction may contribute to the loss of these biradicals in the atmosphere.", "date": "2013-08-01", "date_type": "published", "publication": "Journal of Physical Chemistry Letters", "volume": "4", "number": "15", "publisher": "American Chemical Society", "pagerange": "2525-2529", "id_number": "CaltechAUTHORS:20130830-104625702", "issn": "1948-7185", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20130830-104625702", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Danish Council for Independent Research-Natural Sciences" }, { "agency": "NASA", "grant_number": "NNX08AD29G" }, { "agency": "NSF", "grant_number": "ATM-0934408" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1021/jz401205m", "primary_object": { "basename": "jz401205m_si_001.pdf", "url": "https://authors.library.caltech.edu/records/e0myd-zgf59/files/jz401205m_si_001.pdf" }, "resource_type": "article", "pub_year": "2013", "author_list": "Kjaergaard, Henrik G.; Kurt\u00e9n, Theo; et el." }, { "id": "https://authors.library.caltech.edu/records/eqg5p-8k722", "eprint_id": 40730, "eprint_status": "archive", "datestamp": "2023-08-22 09:44:38", "lastmod": "2023-10-24 17:21:25", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Keppel-Aleks-G", "name": { "family": "Keppel-Aleks", "given": "Gretchen" } }, { "id": "Randerson-J-T", "name": { "family": "Randerson", "given": "James T." }, "orcid": "0000-0001-6559-7387" }, { "id": "Lindsay-K", "name": { "family": "Lindsay", "given": "Keith" } }, { "id": "Stephens-B-B", "name": { "family": "Stephens", "given": "Britton B." } }, { "id": "Moore-J-K", "name": { "family": "Moore", "given": "J. Keith" } }, { "id": "Doney-S-C", "name": { "family": "Doney", "given": "Scott C." }, "orcid": "0000-0002-3683-2437" }, { "id": "Thornton-P-E", "name": { "family": "Thornton", "given": "Peter E." } }, { "id": "Mahowald-N-M", "name": { "family": "Mahowald", "given": "Natalie M." } }, { "id": "Hoffman-Forrest-M", "name": { "family": "Hoffman", "given": "Forrest M." } }, { "id": "Sweeney-C", "name": { "family": "Sweeney", "given": "Colm" }, "orcid": "0000-0001-9568-0050" }, { "id": "Tans-P-P", "name": { "family": "Tans", "given": "Pieter P." } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Wofsy-S-C", "name": { "family": "Wofsy", "given": "Steven C." }, "orcid": "0000-0002-3990-6737" } ] }, "title": "Atmospheric Carbon Dioxide Variability in the Community Earth System Model: Evaluation and Transient Dynamics during the Twentieth and Twenty-First Centuries", "ispublished": "pub", "full_text_status": "public", "keywords": "Carbon cycle; Carbon dioxide; Aircraft observations; In situ atmospheric observations; Remote sensing; Tracers", "note": "\u00a9 2013 American Meteorological Society.\n\nReceived: July 31, 2012; Final Form: December 19, 2012.\n\nThe CESM project is supported\nby the National Science Foundation and the Office of\nScience (BER) of the U.S. Department of Energy.\nComputing resources were provided by the Climate\nSimulation Laboratory at NCAR's Computational and\nInformation Systems Laboratory (CISL), sponsored by\nthe National Science Foundation and other agencies.\nG.K.A. acknowledges support of a NOAA Climate and\nGlobal Change postdoctoral fellowship. J.T.R., N.M.M.,\nS.C.D., K.L., and J.K.M. acknowledge support of Collaborative\nResearch: Improved Regional and Decadal\nPredictions of the Carbon Cycle (NSF AGS-1048827,\nAGS-1021776, AGS-1048890). The HIPPO Program was\nsupported by NSF Grants ATM-0628575, ATM-0628519,\nand ATM-0628388 to Harvard University, University of\nCalifornia (San Diego), and by University Corporation\nfor Atmospheric Research, University of Colorado/\nCIRES, by the NCAR and by the NOAA Earth System\nResearch Laboratory. Sunyoung Park, Greg Santoni,\nEric Kort, and Jasna Pittman collected data during\nHIPPO. The ACME project was supported by the Office\nof Biological and Environmental Research of the U.S.\nDepartment of Energy under Contract DE-AC02-\n05CH11231 as part of the Atmospheric Radiation Measurement\nProgram (ARM), the ARM Aerial Facility,\nand the Terrestrial Ecosystem Science Program. TCCON\nmeasurements at Eureka were made by the Canadian\nNetwork for Detection of Atmospheric Composition\nChange (CANDAC) with additional support from the\nCanadian Space Agency. The Lauder TCCON program\nwas funded by the New Zealand Foundation for Research\nScience and Technology contracts CO1X0204,\nCO1X0703, and CO1X0406. Measurements at Darwin\nand Wollongong were supported by Australian Research\nCouncil Grants DP0879468 and DP110103118 and\nwere undertaken by David Griffith, Nicholas Deutscher,\nand Ronald Macatangay. We thank Pauli Heikkinen,\nPetteri Ahonen, and Esko Kyr\u00f6 of the Finnish Meteorological\nInstitute for contributing the Sodankyl\u00e4\nTCCON data. Measurements at Park Falls, Lamont, and\nPasadena were supported by NASA Grant NNX11AG01G\nand the NASA Orbiting Carbon Observatory Program.\nData at these sites were obtained by Geoff Toon, Jean-\nFrancois Blavier, Coleen Roehl, and Debra Wunch. We\nare grateful to the DOE ARM program for technical\nsupport in Lamont and Jeff Ayers for technical support\nat Park Falls. Complete acknowledgments for all sites\ncan be found on the TCCON website: https://tcconwiki.\ncaltech.edu/Network_Policy/Data_Use_Policy.\n\nPublished - jcli-d-12-00589.1.pdf
", "abstract": "Changes in atmospheric CO_2 variability during the twenty-first century may provide insight about ecosystem responses to climate change and have implications for the design of carbon monitoring programs. This paper describes changes in the three-dimensional structure of atmospheric CO_2 for several representative concentration pathways (RCPs 4.5 and 8.5) using the Community Earth System Model\u2013Biogeochemistry (CESM1-BGC). CO_2 simulated for the historical period was first compared to surface, aircraft, and column observations. In a second step, the evolution of spatial and temporal gradients during the twenty-first century was examined. The mean annual cycle in atmospheric CO_2 was underestimated for the historical period throughout the Northern Hemisphere, suggesting that the growing season net flux in the Community Land Model (the land component of CESM) was too weak. Consistent with weak summer drawdown in Northern Hemisphere high latitudes, simulated CO_2 showed correspondingly weak north\u2013south and vertical gradients during the summer. In the simulations of the twenty-first century, CESM predicted increases in the mean annual cycle of atmospheric CO_2 and larger horizontal gradients. Not only did the mean north\u2013south gradient increase due to fossil fuel emissions, but east\u2013west contrasts in CO_2 also strengthened because of changing patterns in fossil fuel emissions and terrestrial carbon exchange. In the RCP8.5 simulation, where CO_2 increased to 1150 ppm by 2100, the CESM predicted increases in interannual variability in the Northern Hemisphere midlatitudes of up to 60% relative to present variability for time series filtered with a 2\u201310-yr bandpass. Such an increase in variability may impact detection of changing surface fluxes from atmospheric observations.", "date": "2013-07", "date_type": "published", "publication": "Journal of Climate", "volume": "26", "number": "13", "publisher": "American Meteorological Society", "pagerange": "4447-4475", "id_number": "CaltechAUTHORS:20130820-092041048", "issn": "0894-8755", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20130820-092041048", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF" }, { "agency": "National Center for Atmospheric Research (NCAR)" }, { "agency": "National Oceanic and Atmospheric Administration (NOAA)" }, { "agency": "NSF", "grant_number": "AGS-1048827" }, { "agency": "NSF", "grant_number": "AGS-1021776" }, { "agency": "NSF", "grant_number": "AGS-1048890" }, { "agency": "NSF", "grant_number": "ATM-0628575" }, { "agency": "NSF", "grant_number": "ATM-0628519" }, { "agency": "NSF", "grant_number": "ATM-0628388" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" }, { "agency": "Canadian Space Agency (CSA)" }, { "agency": "New Zealand Foundation for Research Science and Technology", "grant_number": "CO1X0204" }, { "agency": "New Zealand Foundation for Research Science and Technology", "grant_number": "CO1X0703" }, { "agency": "New Zealand Foundation for Research Science and Technology", "grant_number": "CO1X0406" }, { "agency": "Australian Research Council", "grant_number": "DP0879468" }, { "agency": "Australian Research Council", "grant_number": "DP110103118" }, { "agency": "NASA", "grant_number": "NNX11AG01G" }, { "agency": "University Corporation for Atmospheric Research" }, { "agency": "University of Colorado/CIRES" }, { "agency": "Canadian Network for Detection of Atmospheric Composition Change (CANDAC)" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1175/JCLI-D-12-00589.1", "primary_object": { "basename": "jcli-d-12-00589.1.pdf", "url": "https://authors.library.caltech.edu/records/eqg5p-8k722/files/jcli-d-12-00589.1.pdf" }, "resource_type": "article", "pub_year": "2013", "author_list": "Keppel-Aleks, Gretchen; Randerson, James T.; et el." }, { "id": "https://authors.library.caltech.edu/records/r7bpj-k1090", "eprint_id": 41059, "eprint_status": "archive", "datestamp": "2023-08-22 09:36:41", "lastmod": "2023-10-24 23:25:41", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Yoshida-Y", "name": { "family": "Yoshida", "given": "Y." } }, { "id": "Wunch-D", "name": { "family": "Wunch", "given": "D." }, "orcid": "0000-0002-4924-0377" }, { "id": "Roehl-C-M", "name": { "family": "Roehl", "given": "C. M." }, "orcid": "0000-0001-5383-8462" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "Improvement of the retrieval algorithm for GOSAT SWIR XCO_2 and XCH_4 and their validation using TCCON data", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2013 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: 19 December 2012 \u2013 Published in Atmos. Meas. Tech. Discuss.: 30 January 2013. Revised: 23 April 2013 \u2013 Accepted: 3 May 2013 \u2013 Published: 7 June 2013. \n\nThe authors wish to thank Hiroshi Suto for providing useful comments on the non-linearity response of\nTANSO-FTS L1B and the non-linearity-corrected spectral data over ocean used in the sensitivity tests. The authors also wish to\nthank Ha Tran for kindly providing the line mixing and collision induced absorption code used in this study. Retrieval sensitivity tests were conducted on the GOSAT Research Computation Facility. The extended GPV dataset was provided to the GOSAT project\nby JMA. This research was supported in part by the Environment Research and Technology Development Fund (A-1102) of the\nMinistry of the Environment, Japan. US funding for TCCON comes from NASA's Terrestrial Ecology Program, grant number\nNNX11AG01G, the Orbiting Carbon Observatory Program, the Atmospheric C_O2 Observations from Space (ACOS) Program and\nthe DOE/ARM Program. Information about all TCCON sites and their sources of funding can be found on the TCCON website\n(https://tccon-wiki.caltech.edu/).\n\nEdited by: P. Stammes.\n\nPublished - amt-6-1533-2013.pdf
Supplemental Material - amt-6-1533-2013-supplement.pdf
", "abstract": "The column-averaged dry-air mole fractions of carbon dioxide and methane (XCO_2 and XCH_4) have been retrieved from Greenhouse gases Observing SATellite (GOSAT) Short-Wavelength InfraRed (SWIR) observations and released as a SWIR L2 product from the National Institute for Environmental Studies (NIES). XCO_2 and XCH_4 retrieved using the version 01.xx retrieval algorithm showed large negative biases and standard deviations (\u22128.85 and 4.75 ppm for XCO_2 and \u221220.4 and 18.9 ppb for XCH_4, respectively) compared with data of the Total Carbon Column Observing Network (TCCON). Multiple reasons for these error characteristics (e.g., solar irradiance database, handling of aerosol scattering) are identified and corrected in a revised version of the retrieval algorithm (version 02.xx). The improved retrieval algorithm shows much smaller biases and standard deviations (\u22121.48 and 2.09 ppm for XCO_2 and \u22125.9 and 12.6 ppb for XCH_4, respectively) than the version 01.xx. Also, the number of post-screened measurements is increased, especially at northern mid- and high-latitudinal areas.", "date": "2013-06-07", "date_type": "published", "publication": "Atmospheric Measurement Techniques", "volume": "6", "number": "6", "publisher": "European Geosciences Union", "pagerange": "1533-1547", "id_number": "CaltechAUTHORS:20130903-130125782", "issn": "1867-1381", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20130903-130125782", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Ministry of the Environment (Japan)", "grant_number": "A-1102" }, { "agency": "NASA", "grant_number": "NNX11AG01G" }, { "agency": "Department of Energy (DOE)" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/amt-6-1533-2013", "primary_object": { "basename": "amt-6-1533-2013.pdf", "url": "https://authors.library.caltech.edu/records/r7bpj-k1090/files/amt-6-1533-2013.pdf" }, "related_objects": [ { "basename": "amt-6-1533-2013-supplement.pdf", "url": "https://authors.library.caltech.edu/records/r7bpj-k1090/files/amt-6-1533-2013-supplement.pdf" } ], "resource_type": "article", "pub_year": "2013", "author_list": "Yoshida, Y.; Wunch, D.; et el." }, { "id": "https://authors.library.caltech.edu/records/yj3rx-xrr77", "eprint_id": 39268, "eprint_status": "archive", "datestamp": "2023-08-22 09:18:27", "lastmod": "2023-10-24 16:36:58", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Browne-E-C", "name": { "family": "Browne", "given": "E. C." } }, { "id": "Min-K-E", "name": { "family": "Min", "given": "K.-E." } }, { "id": "Wooldridge-P-J", "name": { "family": "Wooldridge", "given": "P. J." } }, { "id": "Apel-E", "name": { "family": "Apel", "given": "E." } }, { "id": "Blake-D-R", "name": { "family": "Blake", "given": "D. R." } }, { "id": "Brune-W-H", "name": { "family": "Brune", "given": "W. H." }, "orcid": "0000-0002-1609-4051" }, { "id": "Cantrell-C-A", "name": { "family": "Cantrell", "given": "C. A." } }, { "id": "Cubison-M-J", "name": { "family": "Cubison", "given": "M. J." } }, { "id": "Diskin-G-S", "name": { "family": "Diskin", "given": "G. S." }, "orcid": "0000-0002-3617-0269" }, { "id": "Jimenez-J-L", "name": { "family": "Jimenez", "given": "J. L." }, "orcid": "0000-0001-6203-1847" }, { "id": "Weinheimer-A-J", "name": { "family": "Weinheimer", "given": "A. J." }, "orcid": "0000-0001-6175-8286" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Wisthaler-A", "name": { "family": "Wisthaler", "given": "A." } }, { "id": "Cohen-R-C", "name": { "family": "Cohen", "given": "R. C." }, "orcid": "0000-0001-6617-7691" } ] }, "title": "Observations of total RONO_2 over the boreal forest: NO_x sinks and HNO_3 sources", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2013 the 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: 11 December 2012; Published in Atmos. Chem. Phys. Discuss.: 4 January 2013 Revised: 8 April 2013; Accepted: 12 April 2013; Published: 2 May 2013.\n\nThe analysis described here was supported by NASA grant NNX08AR13G and a NASA Earth Systems Science Fellowship to ECB. MJC and JLJ were supported by NASA NNX08AD39G and NNX12AC03G. PTR-MS measurements were supported by the Austrian Research Promotion Agency (FFG-ALR) and the Tiroler Zukunftstiftung, and were carried out with the help/support of T. Mikoviny, M. Graus, A. Hansel and T. D. Maerk. We thank the NASA ground and flight crews for their\nhard work during ARCTAS.\nEdited by: F. Keutsch\n\nPublished - acp-13-4543-2013.pdf
", "abstract": "In contrast with the textbook view of remote chemistry where HNO_3 formation is the primary sink of nitrogen oxides, recent theoretical analyses show that formation of RONO_2 (\u03a3ANs) from isoprene and other terpene precursors is the primary net chemical loss of nitrogen oxides over the remote continents where the concentration of nitrogen oxides is low. This then increases the prominence of questions concerning the chemical lifetime and ultimate fate of \u03a3ANs. We present observations of nitrogen oxides and organic molecules collected over the Canadian boreal forest during the summer which show that \u03a3ANs account for ~20% of total oxidized nitrogen and that their instantaneous production rate is larger than that of HNO3. This confirms the primary role of reactions producing \u03a3ANs as a control over the lifetime of NO_x (NO_x = NO + NO_2) in remote, continental environments. However, HNO_3 is generally present in larger concentrations than \u03a3ANs indicating that the atmospheric lifetime of \u03a3ANs is shorter than the HNO_3 lifetime. We investigate a range of proposed loss mechanisms that would explain the inferred lifetime of \u03a3ANs finding that in combination with deposition, two processes are consistent with the observations: (1) rapid ozonolysis of isoprene nitrates where at least ~40% of the ozonolysis products release NO_x from the carbon backbone and/or (2) hydrolysis of particulate organic nitrates with HNO_3 as a product. Implications of these ideas for our understanding of NO_x and NO_y budget in remote and rural locations are discussed.", "date": "2013-05-02", "date_type": "published", "publication": "Atmospheric Chemistry and Physics", "volume": "13", "number": "9", "publisher": "European Geosciences Union", "pagerange": "4543-4562", "id_number": "CaltechAUTHORS:20130709-103850684", "issn": "1680-7316", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20130709-103850684", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NNX08AR13G" }, { "agency": "NASA Earth Systems Science Fellowship" }, { "agency": "NASA", "grant_number": "NNX08AD39G" }, { "agency": "NASA", "grant_number": "NNX12AC03G" }, { "agency": "FWF Der Wissenschaftsfonds" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/acp-13-4543-2013", "primary_object": { "basename": "acp-13-4543-2013.pdf", "url": "https://authors.library.caltech.edu/records/yj3rx-xrr77/files/acp-13-4543-2013.pdf" }, "resource_type": "article", "pub_year": "2013", "author_list": "Browne, E. C.; Min, K.-E.; et el." }, { "id": "https://authors.library.caltech.edu/records/78kfw-e8z92", "eprint_id": 39445, "eprint_status": "archive", "datestamp": "2023-08-19 19:39:35", "lastmod": "2023-10-24 16:49:14", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Keppel-Aleks-G", "name": { "family": "Keppel-Aleks", "given": "G." } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" }, { "id": "O'Dell-C-W", "name": { "family": "O'Dell", "given": "C. W." } }, { "id": "Wunch-D", "name": { "family": "Wunch", "given": "D." }, "orcid": "0000-0002-4924-0377" } ] }, "title": "Towards constraints on fossil fuel emissions from total column carbon dioxide", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 Author(s) 2013. 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: 1 November 2012; Published in Atmos. Chem. Phys. Discuss.: 21 November 2012 Revised: 26 February 2013; Accepted: 22 March 2013; Published: 26 April 2013. \n\nThe satellite data were produced by the ACOS/OCO-2 project at the Jet Propulsion Laboratory, California Institute of Technology. The spectra were acquired by the GOSAT project. Support for this work from NASA grants NNX11AG016, NNX08AI86G, and NNX10AT83G is gratefully acknowledged. \n\nWe acknowledge the Keck Institute for Space Studies for inspiring this study. GKA acknowledges support from a NOAA Climate and Global Change postdoctoral fellowship.\n\nPublished - acp-13-4349-2013.pdf
", "abstract": "We assess the large-scale, top-down constraints on regional fossil fuel emissions provided by observations of atmospheric total column CO_2, X_CO_2. Using an atmospheric general circulation model (GCM) with underlying fossil emissions, we determine the influence of regional fossil fuel emissions on global X_CO_2 fields. We quantify the regional contrasts between source and upwind regions and probe the sensitivity of atmospheric X_CO_2 to changes in fossil fuel emissions. Regional fossil fuel X_CO_2 contrasts can exceed 0.7 ppm based on 2007 emission estimates, but have large seasonal variations due to biospheric fluxes. Contamination by clouds reduces the discernible fossil signatures. Nevertheless, our simulations show that atmospheric fossil X_CO_2 can be tied to its source region and that changes in the regional X_CO_2 contrasts scale linearly with emissions. We test the GCM results against X_CO_2 data from the GOSAT satellite. Regional X_CO_2 contrasts in GOSAT data generally scale with the predictions from the GCM, but the comparison is limited by the moderate precision of and relatively few observations from the satellite. We discuss how this approach may be useful as a policy tool to verify national fossil emissions, as it provides an independent, observational constraint.", "date": "2013-04-26", "date_type": "published", "publication": "Atmospheric Chemistry and Physics", "volume": "13", "number": "8", "publisher": "European Geosciences Union", "pagerange": "4349-4357", "id_number": "CaltechAUTHORS:20130718-112224702", "issn": "1680-7316", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20130718-112224702", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NNX11AG016" }, { "agency": "NASA", "grant_number": "NNX08AI86G" }, { "agency": "NASA", "grant_number": "NNX10AT83G" }, { "agency": "National Oceanic and Atmospheric Administration (NOAA)" } ] }, "local_group": { "items": [ { "id": "Keck-Institute-for-Space-Studies" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/acp-13-4349-2013", "primary_object": { "basename": "acp-13-4349-2013.pdf", "url": "https://authors.library.caltech.edu/records/78kfw-e8z92/files/acp-13-4349-2013.pdf" }, "resource_type": "article", "pub_year": "2013", "author_list": "Keppel-Aleks, G.; Wennberg, P. O.; et el." }, { "id": "https://authors.library.caltech.edu/records/mtkt2-vwy98", "eprint_id": 91362, "eprint_status": "archive", "datestamp": "2023-08-19 14:43:30", "lastmod": "2023-10-19 22:26:55", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Oshchepkov-Sergey", "name": { "family": "Oshchepkov", "given": "Sergey" } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Wunch-Debra", "name": { "family": "Wunch", "given": "Debra" }, "orcid": "0000-0002-4924-0377" } ] }, "title": "Effects of atmospheric light scattering on spectroscopic observations of greenhouse gases from space. Part 2: Algorithm intercomparison in the GOSAT data processing for CO\u2082 retrievals over TCCON sites", "ispublished": "pub", "full_text_status": "public", "keywords": "GOSAT algorithms", "note": "\u00a9 2013 American Geophysical Union. \n\nReceived 28 November 2012; revised 9 September 2012; accepted 28 December 2012; published 11 February 2013. \n\nGOSAT is a joint effort of the Japan Aerospace Exploration Agency (JAXA), the National Institute for Environmental Studies (NIES), and the Ministry of the Environment (MOE), Japan. Part of this work on ACOS B2.9 was performed at the Jet Propulsion Laboratory, California Institute of Technology, under contract with NASA. GOSAT spectra were kindly provided to the California Institute of Technology through a memorandum of understanding between JAXA and NASA. U.S. funding for TCCON is provided by NASA's Terrestrial Ecology Program (grant number NNX11AG01G), the Orbiting Carbon Observatory Program, the Atmospheric CO_2 Observations from Space (ACOS) Program, and the Department of Energy/Atmospheric Radiation Measurement (DOE/ARM) Program. The Darwin TCCON site was built at Caltech with funding from the OCO project and is operated by the University of Wollongong, with travel funds for maintenance and equipment costs funded by the OCO\u20102 project. We acknowledge funding to support Darwin and Wollongong from the Australian Research Council, Projects LE0668470, DP0879468, DP110103118, and LP0562346. Lauder TCCON measurements are funded by New Zealand Foundation of Research Science and Technology contracts C01X0204 and CO1X0406. We acknowledge financial support of the Bia\u0142ystok and Orl\u00e9ans TCCON sites from the Senate of Bremen and EU projects IMECC, GEOMON and InGOS as well as maintenance and logistical work provided by AeroMeteo Service (Bia\u0142ystok) and the RAMCES team at LSCE (Gif\u2010sur\u2010Yvette, France) and additional operational funding from the NIES GOSAT project. The Garmisch TCCON team acknowledges funding by the EC\u2010INGOS project. Development of RemoTeC was partly funded by ESA through the GHG\u2010CCI project (S. Guerlet) and by Deutsche Forschungsgemeinschaft (DFG) through grant BU2599/1\u20101 (A. Butz). The JRA\u201025/JCDAS data sets used for atmospheric transport modeling were provided by the cooperative, long\u2010term reanalysis project by the Japan Meteorological Agency (JMA) and Central Research Institute of Electric Power Industry (CRIEPI). The authors thank Dr. Sasano, Director of the Center for Global Environmental Research at the NIES, the members of the NIES GOSAT and NASA ACOS projects.\n\nPublished - Oshchepkov_et_al-2013-Journal_of_Geophysical_Research_3A_Atmospheres.pdf
", "abstract": "This report is the second in a series of companion papers describing the effects of atmospheric light scattering in observations of atmospheric carbon dioxide (CO\u2082) by the Greenhouse gases Observing SATellite (GOSAT), in orbit since 23 January 2009. Here we summarize the retrievals from six previously published algorithms; retrieving column\u2010averaged dry air mole fractions of CO\u2082 (X_(CO\u2082)) during 22\u2009months of operation of GOSAT from June 2009. First, we compare data products from each algorithm with ground\u2010based remote sensing observations by Total Carbon Column Observing Network (TCCON). Our GOSAT\u2010TCCON coincidence criteria select satellite observations within a 5\u00b0 radius of 11 TCCON sites. We have compared the GOSAT\u2010TCCON X_(CO\u2082) regression slope, standard deviation, correlation and determination coefficients, and global and station\u2010to\u2010station biases. The best agreements with TCCON measurements were detected for NIES 02.xx and RemoTeC. Next, the impact of atmospheric light scattering on X_(CO\u2082) retrievals was estimated for each data product using scan by scan retrievals of light path modification with the photon path length probability density function (PPDF) method. After a cloud pre\u2010filtering test, approximately 25% of GOSAT soundings processed by NIES 02.xx, ACOS B2.9, and UoL\u2010FP:\u20093G and 35% processed by RemoTeC were found to be contaminated by atmospheric light scattering. This study suggests that NIES 02.xx and ACOS B2.9 algorithms tend to overestimate aerosol amounts over bright surfaces, resulting in an underestimation of X_(CO\u2082) for GOSAT observations. Cross\u2010comparison between algorithms shows that ACOS B2.9 agrees best with NIES 02.xx and UoL\u2010FP:\u20093G while RemoTeC X_(CO\u2082) retrievals are in a best agreement with NIES PPDF\u2010D.", "date": "2013-02-16", "date_type": "published", "publication": "Journal of Geophysical Research. Atmospheres", "volume": "118", "number": "3", "publisher": "American Geophysical Union", "pagerange": "1493-1512", "id_number": "CaltechAUTHORS:20181130-101030855", "issn": "2169-897X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20181130-101030855", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA/JPL/Caltech" }, { "agency": "NASA", "grant_number": "NNX11AG01G" }, { "agency": "Department of Energy (DOE)" }, { "agency": "Orbiting Carbon Observatory Program" }, { "agency": "Australian Research Council", "grant_number": "LE0668470" }, { "agency": "Australian Research Council", "grant_number": "DP0879468" }, { "agency": "Australian Research Council", "grant_number": "DP110103118" }, { "agency": "Australian Research Council", "grant_number": "LP0562346" }, { "agency": "New Zealand Foundation of Research Science and Technology", "grant_number": "C01X0204" }, { "agency": "New Zealand Foundation for Research Science and Technology", "grant_number": "CO1X0406" }, { "agency": "Senate of Bremen" }, { "agency": "European Union", "grant_number": "IMECC" }, { "agency": "European Union", "grant_number": "GEOMON" }, { "agency": "European Union", "grant_number": "InGOS" }, { "agency": "National Institute for Environmental Studies (Japan)" }, { "agency": "European Space Agency (ESA)" }, { "agency": "Deutsche Forschungsgemeinschaft (DFG)", "grant_number": "BU2599/1\u20101" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1002/jgrd.50146", "primary_object": { "basename": "Oshchepkov_et_al-2013-Journal_of_Geophysical_Research_3A_Atmospheres.pdf", "url": "https://authors.library.caltech.edu/records/mtkt2-vwy98/files/Oshchepkov_et_al-2013-Journal_of_Geophysical_Research_3A_Atmospheres.pdf" }, "resource_type": "article", "pub_year": "2013", "author_list": "Oshchepkov, Sergey; Wennberg, Paul O.; et el." }, { "id": "https://authors.library.caltech.edu/records/xykm8-cva10", "eprint_id": 37839, "eprint_status": "archive", "datestamp": "2023-08-22 08:42:30", "lastmod": "2023-10-23 19:02:39", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Belikov-D-A", "name": { "family": "Belikov", "given": "D. A." } }, { "id": "Maksyutov-S", "name": { "family": "Maksyutov", "given": "S." }, "orcid": "0000-0002-1200-9577" }, { "id": "Sherlock-V", "name": { "family": "Sherlock", "given": "V." } }, { "id": "Aoki-S", "name": { "family": "Aoki", "given": "S." } }, { "id": "Deutscher-N-M", "name": { "family": "Deutscher", "given": "N. M." }, "orcid": "0000-0002-2906-2577" }, { "id": "Dohe-S", "name": { "family": "Dohe", "given": "S." } }, { "id": "Griffith-D", "name": { "family": "Griffith", "given": "D." } }, { "id": "Kyro-E", "name": { "family": "Kyro", "given": "E." } }, { "id": "Morino-I", "name": { "family": "Morino", "given": "I." } }, { "id": "Nakazawa-T", "name": { "family": "Nakazawa", "given": "T." } }, { "id": "Notholt-J", "name": { "family": "Notholt", "given": "J." } }, { "id": "Rettinger-M", "name": { "family": "Rettinger", "given": "M." } }, { "id": "Schneider-M", "name": { "family": "Schneider", "given": "M." } }, { "id": "Sussmann-R", "name": { "family": "Sussmann", "given": "R." } }, { "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": "Wunch-D", "name": { "family": "Wunch", "given": "D." }, "orcid": "0000-0002-4924-0377" } ] }, "title": "Simulations of column-averaged CO_2 and CH_4 using the NIES TM with a hybrid sigma-isentropic (\u03c3-\u03b8) vertical coordinate", "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: 15 November 2011. Published in Atmos. Chem. Phys. Discuss.: 23 March 2012. Revised: 5 January 2013. Accepted: 18 January 2013. Published: 15 February 2013. We thank T. Machida for aircraft observations\nof CH4 over Surgut (Russia); and A. E. Andrews, T. M. Hall, and D. W. Waugh for providing observation data of the mean age of air in the stratosphere. We also thank P. K. Patra and the TransCom-CH4 and CONTRAIL TMI communities for model setups, initial profiles, and emission fluxes used in the tracer transport simulation. We also thank S. Oshchepkov for insightful discussions and suggestions regarding the manuscript. The meteorological datasets used for this study were provided by the cooperative research project of the JRA-25/JCDAS long-term reanalysis by the Japan Meteorological Agency (JMA) and the Central Research Institute of Electric Power Industry (CRIEPI). We also thank GLOBALVIEWCO2/CH4 authors. For calculations, we used the computational resources of the NIES supercomputer system (NEC SX-8R/128M16). 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/. US funding for TCCON comes from NASA's Terrestrial Ecology Program, grant number\nNNX11AG01G, the Orbiting Carbon Observatory Program, the\nAtmospheric CO2 Observations from Space (ACOS) Program and\nthe DOE/ARM Program. The Darwin TCCON site was built at\nCaltech with funding from the OCO project, and is operated by the University of Wollongong, with travel funds for maintenance and equipment costs funded by the OCO-2 project. We acknowledge funding to support Darwin and Wollongong from the Australian Research Council, Projects LE0669470, DP0879468, DP110103118 and LP0562346. Lauder TCCON measurements are funded by New Zealand Foundation of Research Science and Technology contracts C01X0204 and CO1X0406. We acknowledge financial support of the Bialystok and Orleans TCCON sites from the Senate of Bremen and EU projects IMECC and GEOmon, as well as maintenance and logistical work provided by AeroMeteo Service (Bialystok) and the RAMCES team at LSCE (Gif-sur-Yvette, France) and additional operational funding from the National Institute for Environmental Studies (NIES, Japan). Edited by: P. Monks\n\nPublished - acp-13-1713-2013.pdf
", "abstract": "We have developed an improved version of the National Institute for Environmental Studies (NIES) three-dimensional chemical transport model (TM) designed for accurate tracer transport simulations in the stratosphere, using a hybrid sigma-isentropic (\u03c3-\u03b8) vertical coordinate that employs both terrain-following and isentropic parts switched smoothly around the tropopause. The air-ascending rate was derived from the effective heating rate and was used to simulate vertical motion in the isentropic part of the grid (above level 350 K), which was adjusted to fit to the observed age of the air in the stratosphere. Multi-annual simulations were conducted using the NIES TM to evaluate vertical profiles and dry-air column-averaged mole fractions of CO_2 and CH_4. Comparisons with balloon-borne observations over Sanriku (Japan) in 2000\u20132007 revealed that the tracer transport simulations in the upper troposphere and lower stratosphere are performed with accuracies of ~5% for CH_4 and SF_6, and ~1% for CO_2 compared with the observed volume-mixing ratios. The simulated column-averaged dry air mole fractions of atmospheric carbon dioxide (XCO_2) and methane (XCH_4) were evaluated against daily ground-based high-resolution Fourier Transform Spectrometer (FTS) observations measured at twelve sites of the Total Carbon Column Observing Network (TCCON) (Bialystok, Bremen, Darwin, Garmisch, Iza\u00f1a, Lamont, Lauder, Orleans, Park Falls, Sodankyl\u00e4, Tsukuba, and Wollongong) between January 2009 and January 2011. The comparison shows the model's ability to reproduce the site-dependent seasonal cycles as observed by TCCON, with correlation coefficients typically on the order 0.8\u20130.9 and 0.4\u20130.8 for XCO_2 and XCH_4, respectively, and mean model biases of \u00b10.2% and \u00b10.5%, excluding Sodankyl\u00e4, where strong biases are found. The ability of the model to capture the tracer total column mole fractions is strongly dependent on the model's ability to reproduce seasonal variations in tracer concentrations in the planetary boundary layer (PBL). We found a marked difference in the model's ability to reproduce near-surface concentrations at sites located some distance from multiple emission sources and where high emissions play a notable role in the tracer's budget. Comparisons with aircraft observations over Surgut (West Siberia), in an area with high emissions of methane from wetlands, show contrasting model performance in the PBL and in the free troposphere. Thus, the PBL is another critical region for simulating the tracer total column mole fractions.", "date": "2013-02-15", "date_type": "published", "publication": "Atmospheric Chemistry and Physics", "volume": "13", "number": "4", "publisher": "European Geosciences Union", "pagerange": "1713-1732", "id_number": "CaltechAUTHORS:20130410-071421073", "issn": "1680-7316", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20130410-071421073", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NNX11AG01G" }, { "agency": "Department of Energy (DOE)" }, { "agency": "Australian Research Council", "grant_number": "LE0669470" }, { "agency": "Australian Research Council", "grant_number": "DP0879468" }, { "agency": "Australian Research Council", "grant_number": "DP110103118" }, { "agency": "Australian Research Council", "grant_number": "LP0562346" }, { "agency": "New Zealand Foundation of Research Science and Technology", "grant_number": "C01X0204" }, { "agency": "New Zealand Foundation for Research Science and Technology", "grant_number": "CO1X0406" }, { "agency": "Senate of Bremen" }, { "agency": "European Union (EU)" }, { "agency": "National Institute for Environmental Studies (NIES)" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/acp-13-1713-2013", "primary_object": { "basename": "acp-13-1713-2013.pdf", "url": "https://authors.library.caltech.edu/records/xykm8-cva10/files/acp-13-1713-2013.pdf" }, "resource_type": "article", "pub_year": "2013", "author_list": "Belikov, D. A.; Maksyutov, S.; et el." }, { "id": "https://authors.library.caltech.edu/records/g4skh-03377", "eprint_id": 41522, "eprint_status": "archive", "datestamp": "2023-08-22 08:01:03", "lastmod": "2023-10-24 23:48:28", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Xie-Y", "name": { "family": "Xie", "given": "Y." } }, { "id": "Carter-W-P-L", "name": { "family": "Carter", "given": "W. P. L." } }, { "id": "Nolte-C-G", "name": { "family": "Nolte", "given": "C. G." } }, { "id": "Luecken-D-J", "name": { "family": "Luecken", "given": "D. J." } }, { "id": "Hutzell-W-T", "name": { "family": "Hutzell", "given": "W. T." } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Cohen-R-C", "name": { "family": "Cohen", "given": "R. C." }, "orcid": "0000-0001-6617-7691" }, { "id": "Pinder-R-W", "name": { "family": "Pinder", "given": "R. W." } } ] }, "title": "Understanding the impact of recent advances in isoprene photooxidation on simulations of regional air quality", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 Author(s) 2013. 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: 5 September 2012; Published in Atmos. Chem. Phys. Discuss.: 17 October 2012; Revised: 26 January 2013; Accepted: 12 July 2013; Published: 27 August 2013.\n\nWe thank the entire INTEX-NA/ICARTT team for the use of their measurement data. We also thank Barron Henderson, Melinda Beaver, Tad Kleindienst, and John Crounse for helpful conversations. This research was supported by the National Research Council Research Associateship Program pursued at the US Environmental Protection Agency. Fabien Paulot acknowledges support from a NASA Earth and Space Science fellowship. Disclaimer: although this article has been reviewed by the EPA and approved for publication, it does not necessarily reflect EPA policies or views.\nEdited by: J. Thornton\n\nPublished - acp-13-8439-2013.pdf
", "abstract": "The CMAQ (Community Multiscale Air Quality) us model in combination with observations for INTEX-NA/ICARTT (Intercontinental Chemical Transport Experiment\u2013North America/International Consortium for Atmospheric Research on Transport and Transformation) 2004 are used to evaluate recent advances in isoprene oxidation chemistry and provide constraints on isoprene nitrate yields, isoprene nitrate lifetimes, and NO_x recycling rates. We incorporate recent advances in isoprene oxidation chemistry into the SAPRC-07 chemical mechanism within the US EPA (United States Environmental Protection Agency) CMAQ model. The results show improved model performance for a range of species compared against aircraft observations from the INTEX-NA/ICARTT 2004 field campaign. We further investigate the key processes in isoprene nitrate chemistry and evaluate the impact of uncertainties in the isoprene nitrate yield, NO_x (NO_x = NO + NO_2) recycling efficiency, dry deposition velocity, and RO_2 + HO_2 reaction rates. We focus our examination on the southeastern United States, which is impacted by both abundant isoprene emissions and high levels of anthropogenic pollutants. We find that NO_x concentrations increase by 4\u20139% as a result of reduced removal by isoprene nitrate chemistry. O3 increases by 2 ppbv as a result of changes in NO_x. OH concentrations increase by 30%, which can be primarily attributed to greater HO_x production. We find that the model can capture observed total alkyl and multifunctional nitrates (\u2211ANs) and their relationship with O_3 by assuming either an isoprene nitrate yield of 6% and daytime lifetime of 6 hours or a yield of 12% and lifetime of 4 h. Uncertainties in the isoprene nitrates can impact ozone production by 10% and OH concentrations by 6%. The uncertainties in NO_x recycling efficiency appear to have larger effects than uncertainties in isoprene nitrate yield and dry deposition velocity. Further progress depends on improved understanding of isoprene oxidation pathways, the rate of NOx recycling from isoprene nitrates, and the fate of the secondary, tertiary, and further oxidation products of isoprene.", "date": "2013", "date_type": "published", "publication": "Atmospheric Chemistry and Physics", "volume": "13", "number": "16", "publisher": "European Geosciences Union", "pagerange": "8439-8455", "id_number": "CaltechAUTHORS:20130925-111149297", "issn": "1680-7316", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20130925-111149297", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "National Research Council Research Associateship Program" }, { "agency": "NASA Earth and Space Science Fellowship" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/acp-13-8439-2013", "primary_object": { "basename": "acp-13-8439-2013.pdf", "url": "https://authors.library.caltech.edu/records/g4skh-03377/files/acp-13-8439-2013.pdf" }, "resource_type": "article", "pub_year": "2013", "author_list": "Xie, Y.; Carter, W. P. L.; et el." }, { "id": "https://authors.library.caltech.edu/records/cgqvy-fek37", "eprint_id": 55067, "eprint_status": "archive", "datestamp": "2023-08-22 08:02:15", "lastmod": "2023-10-20 21:19:05", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "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": "Toon-G", "name": { "family": "Toon", "given": "G." } }, { "id": "Risi-C", "name": { "family": "Risi", "given": "C." }, "orcid": "0000-0002-8267-453X" }, { "id": "Scheepmaker-R-A", "name": { "family": "Scheepmaker", "given": "R." } }, { "id": "Lee-J-E", "name": { "family": "Lee", "given": "J.-E" } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Worden-J", "name": { "family": "Worden", "given": "J." } } ] }, "title": "Water vapor isotopologue retrievals from high-resolution GOSAT shortwave infrared spectra", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2013 Author(s). This work is distributed under the Creative Commons Attribution 3.0 License. Received: 11 July 2012. Published in Atmos. Meas. Tech. Discuss.: 6 September 2012 Revised: 19 December 2012. Accepted: 21 December 2012. Published: 7 February 2013.\n\nPart 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. GOSAT Level 1B products (spectral data) were provided by the GOSAT Project (JAXA, NIES, and Ministry of the Environment Japan). US funding for TCCON comes from NASA's Terrestrial Ecology Program (NNX08A186G), the Orbiting Carbon Observatory Program (NAS7-03001), the DOE/ARM Program and the Atmospheric CO_2 Observations from Space Program. R.S. was funded by the Netherlands Space Office as part of the User Support Programme Space Research under project GO-AO/16.\n\nEdited by: M. Weber.\n\nPublished - amt-6-263-2013.pdf
", "abstract": "Remote sensing of the isotopic composition of water vapor can provide valuable information on the hydrological cycle. Here, we demonstrate the feasibility of retrievals of the relative abundance of HDO (the HDO/H_2O ratio) from the Japanese GOSAT satellite. For this purpose, we use high spectral resolution nadir radiances around 6400 cm^(\u22121) (1.56 \u03bcm) to retrieve vertical column amounts of H_2O and HDO. Retrievals of H_2O correlate well with ECMWF (European Centre for Medium-Range Weather Forecasts) integrated profiles (r^2 = 0.96). Typical precision errors in the retrieved column-averaged deuterium depletion (\u03b4D) are 20\u201340\u2030. We compare \u03b4D against a TCCON (Total Carbon Column Observing Network) ground-based station in Lamont, Oklahoma. Using retrievals in very dry areas over Antarctica, we detect a small systematic offset in retrieved H_2O and HDO column amounts and take this into account for a bias correction of \u03b4D. Monthly averages of \u03b4D in the June 2009 to September 2011 time frame are well correlated with TCCON (r^2 = 0.79) and exhibit a slope of 0.98 (1.23 if not bias corrected). We also compare seasonal averages on the global scale with results from the SCIAMACHY instrument in the 2003\u20132005 time frame. Despite the lack of temporal overlap, seasonal averages in general agree well, with spatial correlations (r^2) ranging from 0.62 in September through November to 0.83 in June through August. However, we observe higher variability in GOSAT \u03b4D, indicated by fitted slopes between 1.2 and 1.46. The discrepancies are likely related to differences in vertical sensitivities but warrant further validation of both GOSAT and SCIAMACHY and an extension of the validation dataset.", "date": "2013", "date_type": "published", "publication": "Atmospheric Measurement Techniques", "volume": "6", "number": "2", "publisher": "European Geosciences Union", "pagerange": "263-274", "id_number": "CaltechAUTHORS:20150220-135225324", "issn": "1867-1381", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150220-135225324", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA/JPL/Caltech" }, { "agency": "NASA", "grant_number": "NNX08A186G" }, { "agency": "NASA", "grant_number": "NAS7-03001" }, { "agency": "Netherlands Space Office", "grant_number": "GO-AO/16" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/amt-6-263-2013", "primary_object": { "basename": "amt-6-263-2013.pdf", "url": "https://authors.library.caltech.edu/records/cgqvy-fek37/files/amt-6-263-2013.pdf" }, "resource_type": "article", "pub_year": "2013", "author_list": "Frankenberg, C.; Wunch, D.; et el." }, { "id": "https://authors.library.caltech.edu/records/3x61a-rjc89", "eprint_id": 35400, "eprint_status": "archive", "datestamp": "2023-08-22 06:51:17", "lastmod": "2023-10-20 16:11:00", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Mao-J", "name": { "family": "Mao", "given": "J." } }, { "id": "Ren-Xinrong", "name": { "family": "Ren", "given": "X." } }, { "id": "Zhang-L", "name": { "family": "Zhang", "given": "L." } }, { "id": "Van-Duin-D-M", "name": { "family": "Van Duin", "given": "D. M." } }, { "id": "Cohen-R-C", "name": { "family": "Cohen", "given": "R. C." }, "orcid": "0000-0001-6617-7691" }, { "id": "Park-J-H", "name": { "family": "Park", "given": "J.-H." } }, { "id": "Goldstein-A-H", "name": { "family": "Goldstein", "given": "A. H." }, "orcid": "0000-0003-4014-4896" }, { "id": "Paulot-F", "name": { "family": "Paulot", "given": "F." }, "orcid": "0000-0001-7534-4922" }, { "id": "Beaver-M-R", "name": { "family": "Beaver", "given": "M. R." } }, { "id": "Crounse-J-D", "name": { "family": "Crounse", "given": "J. D." }, "orcid": "0000-0001-5443-729X" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" }, { "id": "DiGangi-J-P", "name": { "family": "DiGangi", "given": "J. P." }, "orcid": "0000-0002-6764-8624" }, { "id": "Henry-S-B", "name": { "family": "Henry", "given": "S. B." } }, { "id": "Keutsch-F-N", "name": { "family": "Keutsch", "given": "F. N." } }, { "id": "Park-C", "name": { "family": "Park", "given": "C." } }, { "id": "Schade-G-W", "name": { "family": "Schade", "given": "G. W." } }, { "id": "Wolfe-G-M", "name": { "family": "Wolfe", "given": "G. M." }, "orcid": "0000-0001-6586-4043" }, { "id": "Thornton-J-A", "name": { "family": "Thornton", "given": "J. A." }, "orcid": "0000-0002-5098-4867" }, { "id": "Brune-W-H", "name": { "family": "Brune", "given": "W. H." }, "orcid": "0000-0002-1609-4051" } ] }, "title": "Insights into hydroxyl measurements and atmospheric oxidation in a California forest", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2012 Author(s). \nThis work is distributed\nunder the Creative Commons Attribution 3.0 License.\n\nPublished by Copernicus Publications on behalf of the European Geosciences Union.\nReceived: 22 February 2012. Published in Atmos. Chem. Phys. Discuss.: 2 March 2012. Revised: 17 August 2012. Accepted: 28 August 2012. Published: 7 September 2012. Edited by: J. Williams. We thank the reviewers for their insightful comments. We acknowledge the contributions from Philip Feiner, Jennifer Gielen, and Josh Magerman for HOx measurements and from Robin Weber for CO and O3 measurements during BEARPEX09 study. We also acknowledge William Stockwell and Wendy Goliff for the RACM2 mechanism. We thank Sierra Pacific Industries for the use of their land and the University of California,\nBerkeley, Center for Forestry, Blodgett Forest Research Station for cooperation in facilitating this research. We acknowledge the NSF Atmospheric Chemistry Program for the following grants: #0849475 (WHB); #0922562 (AHG); #0852406 (FNK); #0934408 (POW, JDC, and MRB).\n\nPublished - acp-12-8009-2012.pdf
Supplemental Material - acp-12-8009-2012-supplement.pdf
", "abstract": "The understanding of oxidation in forest atmospheres is being challenged by measurements of unexpectedly large amounts of hydroxyl (OH). A significant number of these OH measurements were made by laser-induced fluorescence in low-pressure detection chambers (called Fluorescence Assay with Gas Expansion (FAGE)) using the Penn State Ground-based Tropospheric Hydrogen Oxides Sensor (GTHOS). We deployed a new chemical removal method to measure OH in parallel with the traditional FAGE method in a California forest. The new method gives on average only 40\u201360% of the OH from the traditional method and this discrepancy is temperature dependent. Evidence indicates that the new method measures atmospheric OH while the traditional method is affected by internally generated OH, possibly from oxidation of biogenic volatile organic compounds. The improved agreement between OH measured by this new technique and modeled OH suggests that oxidation chemistry in at least one forest atmosphere is better understood than previously thought.", "date": "2012-09-07", "date_type": "published", "publication": "Atmospheric Chemistry and Physics", "volume": "12", "number": "17", "publisher": "European Geosciences Union", "pagerange": "8009-8020", "id_number": "CaltechAUTHORS:20121109-150822355", "issn": "1680-7316", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20121109-150822355", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "ATM-0849475" }, { "agency": "NSF", "grant_number": "ATM-0922562" }, { "agency": "NSF", "grant_number": "ATM-0852406" }, { "agency": "NSF", "grant_number": "ATM-0934408" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/acp-12-8009-2012", "primary_object": { "basename": "acp-12-8009-2012-supplement.pdf", "url": "https://authors.library.caltech.edu/records/3x61a-rjc89/files/acp-12-8009-2012-supplement.pdf" }, "related_objects": [ { "basename": "acp-12-8009-2012.pdf", "url": "https://authors.library.caltech.edu/records/3x61a-rjc89/files/acp-12-8009-2012.pdf" } ], "resource_type": "article", "pub_year": "2012", "author_list": "Mao, J.; Ren, X.; et el." }, { "id": "https://authors.library.caltech.edu/records/3d4be-3h187", "eprint_id": 35464, "eprint_status": "archive", "datestamp": "2023-08-19 12:37:55", "lastmod": "2023-10-20 16:22:13", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Mui-Wilton", "name": { "family": "Mui", "given": "Wilton" }, "orcid": "0000-0003-3065-1296" }, { "id": "Wunch-D", "name": { "family": "Wunch", "given": "Debra" }, "orcid": "0000-0002-4924-0377" }, { "id": "Kort-E-A", "name": { "family": "Kort", "given": "Eric A." }, "orcid": "0000-0003-4940-7541" }, { "id": "Blake-D-R", "name": { "family": "Blake", "given": "Donald R." } }, { "id": "Atlas-E-L", "name": { "family": "Atlas", "given": "Elliot L." }, "orcid": "0000-0003-3847-5346" }, { "id": "Santoni-G-W", "name": { "family": "Santoni", "given": "Gregory W." } }, { "id": "Wofsy-S-C", "name": { "family": "Wofsy", "given": "Steven C." }, "orcid": "0000-0002-3990-6737" }, { "id": "Diskin-G-S", "name": { "family": "Diskin", "given": "Glenn S." }, "orcid": "0000-0002-3617-0269" }, { "id": "Jeong-Seongeun", "name": { "family": "Jeong", "given": "Seongeun" }, "orcid": "0000-0003-2032-0127" }, { "id": "Fischer-M-L", "name": { "family": "Fischer", "given": "Marc L." }, "orcid": "0000-0001-7956-2361" } ] }, "title": "On the Sources of Methane to the Los Angeles Atmosphere", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 2012 American Chemical Society. \n\nReceived: March 23, 2012; Revised: July 19, 2012; Accepted: August 1, 2012; Published: August 1, 2012. \n\nData used in this analysis were obtained with support of NASA, NOAA, and the California Air Resources Board. We thank\nStephanie A. Vay for her efforts to obtain the CO2 data during ARCTAS. We thank the Southern California Gas Company for their interest and support in this study. The analysis was supported by the California Institute of Technology. Support for the analysis of the remote sensing data was provided by NASA's Terrestrial Ecology Program. W.M. acknowledges support from a NSF Graduate Research Fellowship. This work was funded in part by the W. M. Keck Institute for Space Studies. G.S. acknowledges support from NSF and EPA STAR graduate fellowships. We thank Joseph Fischer, Larry Hunsaker, Webster Tassat, Marc Vayssi\u00e8res, and Ying-Kang Hsu for sharing advice and data. This work was supported by the California Energy Commission's Public Interest Environmental Research (CEC-PIER) program, the California Air Resources Board, and the US Dept. of Energy through the LBNL Laboratory Directed Research and Development, under contract No. DE-AC02-05CH11231.", "abstract": "We use historical and new atmospheric trace gas observations to refine the estimated source of methane (CH_4) emitted into California's South Coast Air Basin (the larger Los Angeles metropolitan region). Referenced to the California Air Resources Board (CARB) CO emissions inventory, total CH4 emissions are 0.44 \u00b1 0.15 Tg each year. To investigate the possible contribution of fossil fuel emissions, we use ambient air observations of methane (CH_4), ethane (C_(2)H_(6)), and carbon monoxide (CO), together with measured C_(2)H_6 to CH_4 enhancement ratios in the Los Angeles natural gas supply. The observed atmospheric C_(2)H_6 to CH_4 ratio during the ARCTAS (2008) and CalNex (2010) aircraft campaigns is similar to the ratio of these gases in the natural gas supplied to the basin during both these campaigns. Thus, at the upper limit (assuming that the only major source of atmospheric C_(2)H_6 is fugitive emissions from the natural gas infrastructure) these data are consistent with the attribution of most (0.39 \u00b1 0.15 Tg yr^(\u20131)) of the excess CH_4 in the basin to uncombusted losses from the natural gas system (approximately 2.5\u20136% of natural gas delivered to basin customers). However, there are other sources of C_(2)H_6 in the region. In particular, emissions of C_(2)H_6 (and CH_4) from natural gas seeps as well as those associated with petroleum production, both of which are poorly known, will reduce the inferred contribution of the natural gas infrastructure to the total CH_4 emissions, potentially significantly. This study highlights both the value and challenges associated with the use of ethane as a tracer for fugitive emissions from the natural gas production and distribution system.", "date": "2012-09-04", "date_type": "published", "publication": "Environmental Science and Technology", "volume": "46", "number": "17", "publisher": "American Chemical Society", "pagerange": "9282-9289", "id_number": "CaltechAUTHORS:20121114-142929161", "issn": "0013-936X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20121114-142929161", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA" }, { "agency": "National Oceanic and Atmospheric Administration (NOAA)" }, { "agency": "California Air Resources Board" }, { "agency": "Southern California Gas Company" }, { "agency": "Caltech" }, { "agency": "NSF Graduate Research Fellowship" }, { "agency": "Keck Institute for Space Studies (KISS)" }, { "agency": "NSF" }, { "agency": "Environmental Protection Agency (EPA)" }, { "agency": "California Energy Commission" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" } ] }, "local_group": { "items": [ { "id": "Keck-Institute-for-Space-Studies" }, { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1021/es301138y", "resource_type": "article", "pub_year": "2012", "author_list": "Wennberg, Paul O.; Mui, Wilton; et el." }, { "id": "https://authors.library.caltech.edu/records/3k33z-btr66", "eprint_id": 34776, "eprint_status": "archive", "datestamp": "2023-09-14 19:36:32", "lastmod": "2023-10-23 20:53:40", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Kwan-Alan-J", "name": { "family": "Kwan", "given": "A. J." } }, { "id": "Chan-Arthur-W-H", "name": { "family": "Chan", "given": "A. W. H." }, "orcid": "0000-0001-7392-4237" }, { "id": "Ng-Nga-Lee", "name": { "family": "Ng", "given": "N. L." }, "orcid": "0000-0001-8460-4765" }, { "id": "Kjaergaard-H-G", "name": { "family": "Kjaergaard", "given": "H. G." }, "orcid": "0000-0002-7275-8297" }, { "id": "Seinfeld-J-H", "name": { "family": "Seinfeld", "given": "J. H." }, "orcid": "0000-0003-1344-4068" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "Peroxy radical chemistry and OH radical production during the NO_3-initiated oxidation of isoprene", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2012 Author(s). \nThis work is distributed\nunder the Creative Commons Attribution 3.0 License.\nPublished by Copernicus Publications on behalf of the European Geosciences Union. Received: 20 December 2011. Published in Atmos. Chem. Phys. Discuss.: 24 January 2012. Revised: 22 June 2012. Accepted: 7 July 2012. Published: 17 August 2012. This research is funded by the US Department of Energy Biological and Environmental Research Program DE-FG02-05ER63983. Also, this material is based upon work supported by the National Science Foundation (NSF) under grant ATM-0432377 and an NSF Graduate Research Fellowship (AJK). The authors would like to thank C. D. Vecitis, J. Cheng, M. R. Hoffmann, K. Takematsu, and M. Okumura for experimental assistance,\nJ. D. Crounse, N. H. Donahue, N. C. Eddingsaas, F. Paulot, and H. O. T. Pye for helpful discussions, and the anonymous reviewers for helpful comments on the original manuscript.\nEdited by: J. B. Burkholder.\n\nPublished - acp-12-7499-2012.pdf
", "abstract": "Peroxy radical reactions (RO_2 + RO_2) from the NO3-initiated oxidation of isoprene are studied with both gas chromatography and a chemical ionization mass spectrometry technique that allows for more specific speciation of products than in previous studies of this system. We find high nitrate yields (~ 80%), consistent with other studies. We further see evidence of significant hydroxyl radical (OH) formation in this system, which we propose comes from RO_2 + HO_2 reactions with a yield of ~38\u201358%. An additional OH source is the second generation oxidation of the nitrooxyhydroperoxide, which produces OH and a dinitrooxyepoxide with a yield of ~35%. The branching ratio of the radical propagating, carbonyl- and alcohol-forming, and organic peroxide-forming channels of the RO_2 + RO_2 reaction are found to be ~18\u201338%, ~59\u201377%, and ~3\u20134%, respectively. HO_2 formation in this system is lower than has been previously assumed. Addition of RO_2 to isoprene is suggested as a possible route to the formation of several isoprene C_(10)-organic peroxide compounds (ROOR). The nitrooxy, allylic, and C_5 peroxy radicals present in this system exhibit different behavior than the limited suite of peroxy radicals that have been studied to date.", "date": "2012-08-17", "date_type": "published", "publication": "Atmospheric Chemistry and Physics", "volume": "12", "number": "16", "publisher": "European Geosciences Union", "pagerange": "7499-7515", "id_number": "CaltechAUTHORS:20121009-093600608", "issn": "1680-7316", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20121009-093600608", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-FG02-05ER63983" }, { "agency": "NSF", "grant_number": "ATM-0432377" }, { "agency": "NSF Graduate Research Fellowship" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/acp-12-7499-2012", "primary_object": { "basename": "acp-12-7499-2012.pdf", "url": "https://authors.library.caltech.edu/records/3k33z-btr66/files/acp-12-7499-2012.pdf" }, "resource_type": "article", "pub_year": "2012", "author_list": "Kwan, A. J.; Chan, A. W. H.; et el." }, { "id": "https://authors.library.caltech.edu/records/bw7cf-g7881", "eprint_id": 34717, "eprint_status": "archive", "datestamp": "2023-09-14 19:36:08", "lastmod": "2023-10-23 20:53:33", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Eddingsaas-Nathan-C", "name": { "family": "Eddingsaas", "given": "N. C." }, "orcid": "0000-0003-1539-5415" }, { "id": "Loza-Christine-L", "name": { "family": "Loza", "given": "C. L." } }, { "id": "Yee-Lindsay-D", "name": { "family": "Yee", "given": "L. D." }, "orcid": "0000-0001-8965-9319" }, { "id": "Chan-Man-Nin", "name": { "family": "Chan", "given": "M." }, "orcid": "0000-0002-2384-2695" }, { "id": "Schilling-Katherine-A", "name": { "family": "Schilling", "given": "K. A." } }, { "id": "Chhabra-Puneet-S", "name": { "family": "Chhabra", "given": "P. S." } }, { "id": "Seinfeld-J-H", "name": { "family": "Seinfeld", "given": "J. H." }, "orcid": "0000-0003-1344-4068" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "\u03b1-pinene photooxidation under controlled chemical conditions \u2013 Part 2: SOA yield and composition in low- and high-NO\u2093 environments", "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. Received: 2 March 2012 \u2013 Published in Atmos. Chem. Phys. Discuss.: 4 April 2012. Revised: 26 July 2012 \u2013 Accepted: 30 July 2012 \u2013 Published: 16 August 2012. \nThis work was supported in part by Department of Energy grant DE-SC0006626 and National Science Foundation grant AGS-1057183. N. Eddingsaas was supported by the Camille and Henry Dreyfus Postdoctoral Program in Environmental Chemistry. C. Loza and L. Yee were supported by National Science Foundation Graduate Research Fellowships.\n\nPublished - acp-12-7413-2012.pdf
", "abstract": "The gas-phase oxidation of \u03b1-pinene produces a large amount of secondary organic aerosol (SOA) in the atmosphere. A number of carboxylic acids, organosulfates and nitrooxy organosulfates associated with \u03b1-pinene have been found in field samples and some are used as tracers of \u03b1-pinene oxidation. \u03b1-pinene reacts readily with OH and O\u2083 in the atmosphere followed by reactions with both HO\u2082 and NO. Due to the large number of potential reaction pathways, it can be difficult to determine what conditions lead to SOA. To better understand the SOA yield and chemical composition from low- and high-NO\u2093 OH oxidation of \u03b1-pinene, studies were conducted in the Caltech atmospheric chamber under controlled chemical conditions. Experiments used low O\u2083 concentrations to ensure that OH was the main oxidant and low \u03b1-pinene concentrations such that the peroxy radical (RO\u2082) reacted primarily with either HO\u2082 under low-NO\u2093 conditions or NO under high-NO\u2093 conditions. SOA yield was suppressed under conditions of high-NO\u2093. SOA yield under high-NO\u2093 conditions was greater when ammonium sulfate/sulfuric acid seed particles (highly acidic) were present prior to the onset of growth than when ammonium sulfate seed particles (mildly acidic) were present; this dependence was not observed under low-NO\u2093 conditions. When aerosol seed particles were introduced after OH oxidation, allowing for later generation species to be exposed to fresh inorganic seed particles, a number of low-NO\u2093 products partitioned to the highly acidic aerosol. This indicates that the effect of seed acidity and SOA yield might be under-estimated in traditional experiments where aerosol seed particles are introduced prior to oxidation. We also identify the presence of a number of carboxylic acids that are used as tracer compounds of \u03b1-pinene oxidation in the field as well as the formation of organosulfates and nitrooxy organosulfates. A number of the carboxylic acids were observed under all conditions, however, pinic and pinonic acid were only observed under low-NO\u2093 conditions. Evidence is provided for particle-phase sulfate esterification of multi-functional alcohols.", "date": "2012-08-16", "date_type": "published", "publication": "Atmospheric Chemistry and Physics", "volume": "12", "number": "16", "publisher": "European Geosciences Union", "pagerange": "7413-7427", "id_number": "CaltechAUTHORS:20121005-124120015", "issn": "1680-7316", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20121005-124120015", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0006626" }, { "agency": "NSF", "grant_number": "AGS-1057183" }, { "agency": "Camille and Henry Dreyfus Foundation" }, { "agency": "NSF Graduate Research Fellowship" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/acp-12-7413-2012", "primary_object": { "basename": "acp-12-7413-2012.pdf", "url": "https://authors.library.caltech.edu/records/bw7cf-g7881/files/acp-12-7413-2012.pdf" }, "resource_type": "article", "pub_year": "2012", "author_list": "Eddingsaas, N. C.; Loza, C. L.; et el." }, { "id": "https://authors.library.caltech.edu/records/nbqew-q2p26", "eprint_id": 34775, "eprint_status": "archive", "datestamp": "2023-08-22 06:22:04", "lastmod": "2023-10-19 21:52:07", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Olson-J-R", "name": { "family": "Olson", "given": "J. R." } }, { "id": "Beaver-M-R", "name": { "family": "Beaver", "given": "M." } }, { "id": "Crounse-J-D", "name": { "family": "Crounse", "given": "J." }, "orcid": "0000-0001-5443-729X" }, { "id": "St-Clair-J-M", "name": { "family": "St. Clair", "given": "J." }, "orcid": "0000-0002-9367-5749" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "An analysis of fast photochemistry over high northern latitudes during spring and summer using in-situ observations from ARCTAS and TOPSE", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2012 Author(s). \nThis work is distributed\nunder the Creative Commons Attribution 3.0 License.\nPublished by Copernicus Publications on behalf of the European Geosciences Union. \n\n\nReceived: 12 March 2012. Published in Atmos. Chem. Phys. Discuss.: 11 April 2012.\nRevised: 9 July 2012. Accepted: 10 July 2012. Published: 1 August 2012. The ARCTAS mission was funded by the NASA Global Tropospheric Chemistry Program, the NASA Radiation Sciences Program, and the California Air Resources Board. We gratefully acknowledge the NASA aircraft crews and\nscience team. The two anonymous reviewers for this manuscript are also thanked. Edited by: W. T. Sturges.\n\nPublished - acp-12-6799-2012.pdf
", "abstract": "Observations of chemical constituents and meteorological quantities obtained during the two Arctic phases of the airborne campaign ARCTAS (Arctic Research of the Composition of the Troposphere from Aircraft and Satellites) are analyzed using an observationally constrained steady state box model. Measurements of OH and HO_2 from the Penn State ATHOS instrument are compared to model predictions. Forty percent of OH measurements below 2 km are at the limit of detection during the spring phase (ARCTAS-A). While the median observed-to-calculated ratio is near one, both the scatter of observations and the model uncertainty for OH are at the magnitude of ambient values. During the summer phase (ARCTAS-B), model predictions of OH are biased low relative to observations and demonstrate a high sensitivity to the level of uncertainty in NO observations. Predictions of HO_2 using observed CH_2O and H_2O_2 as model constraints are up to a factor of two larger than observed. A temperature-dependent terminal loss rate of HO_2 to aerosol recently proposed in the literature is shown to be insufficient to reconcile these differences. A comparison of ARCTAS-A to the high latitude springtime portion of the 2000 TOPSE campaign (Tropospheric Ozone Production about the Spring Equinox) shows similar meteorological and chemical environments with the exception of peroxides; observations of H_2O_2 during ARCTAS-A were 2.5 to 3 times larger than those during TOPSE. The cause of this difference in peroxides remains unresolved and has important implications for the Arctic HO_x budget. Unconstrained model predictions for both phases indicate photochemistry alone is unable to simultaneously sustain observed levels of CH_2O and H_2O_2; however when the model is constrained with observed CH_2O, H_2O_2 predictions from a range of rainout parameterizations bracket its observations. A mechanism suitable to explain observed concentrations of CH_2O is uncertain. Free tropospheric observations of acetaldehyde (CH_3CHO) are 2\u20133 times larger than its predictions, though constraint of the model to those observations is sufficient to account for less than half of the deficit in predicted CH_2O. The box model calculates gross O_3 formation during spring to maximize from 1\u20134 km at 0.8 ppbv d^(\u22121), in agreement with estimates from TOPSE, and a gross production of 2\u20134 ppbv d^(\u22121) in the boundary layer and upper troposphere during summer. Use of the lower observed levels of HO_2 in place of model predictions decreases the gross production by 25\u201350%. Net O_3 production is near zero throughout the ARCTAS-A troposphere, and is 1\u20132 ppbv in the boundary layer and upper altitudes during ARCTAS-B.", "date": "2012-08-01", "date_type": "published", "publication": "Atmospheric Chemistry and Physics", "volume": "12", "number": "15", "publisher": "European Geosciences Union", "pagerange": "6799-6825", "id_number": "CaltechAUTHORS:20121009-090156604", "issn": "1680-7316", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20121009-090156604", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA" }, { "agency": "California Air Resources Board" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/acp-12-6799-2012", "primary_object": { "basename": "acp-12-6799-2012.pdf", "url": "https://authors.library.caltech.edu/records/nbqew-q2p26/files/acp-12-6799-2012.pdf" }, "resource_type": "article", "pub_year": "2012", "author_list": "Olson, J. R.; Beaver, M.; et el." }, { "id": "https://authors.library.caltech.edu/records/c0ebw-dz302", "eprint_id": 34651, "eprint_status": "archive", "datestamp": "2023-08-19 11:47:26", "lastmod": "2023-10-19 21:21:21", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Eddingsaas-Nathan-C", "name": { "family": "Eddingsaas", "given": "N. C." }, "orcid": "0000-0003-1539-5415" }, { "id": "Loza-Christine-L", "name": { "family": "Loza", "given": "C. L." } }, { "id": "Yee-Lindsay-D", "name": { "family": "Yee", "given": "L. D." }, "orcid": "0000-0001-8965-9319" }, { "id": "Seinfeld-J-H", "name": { "family": "Seinfeld", "given": "J. H." }, "orcid": "0000-0003-1344-4068" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "\u03b1-pinene photooxidation under controlled chemical conditions \u2013 Part 1: Gas-phase composition in low- and high-NO\u2093 environments", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2012 Author(s).\nPublished by Copernicus Publications on behalf of the European Geosciences Union.\n\nThis work is distributed\nunder the Creative Commons Attribution 3.0 License.\n\nReceived: 29 December 2011. Published in Atmos. Chem. Phys. Discuss.: 1 March 2012. Revised: 21 June 2012. Accepted: 1 July 2012. Published: 25 July 2012. This work was supported in part by Department of Energy grant DE-SC0006626 and National Science Foundation grant AGS-1057183. N. Eddingsaas was supported by the Camille and Henry Dreyfus Postdoctoral Program in Environmental Chemistry. C. Loza and L. Yee were supported by National Science Foundation Graduate Research Fellowships. The\nauthors would like to thank John Crounse for helpful discussion.\nEdited by: F. Keutsch\n\nPublished - acp-12-6489-2012.pdf
Supplemental Material - acp-12-6489-2012-supplement.pdf
", "abstract": "The OH oxidation of \u03b1-pinene under both low- and high-NO\u2093 environments was studied in the Caltech atmospheric chambers. Ozone was kept low to ensure OH was the oxidant. The initial \u03b1-pinene concentration was 20\u201350 ppb to ensure that the dominant peroxy radical pathway under low-NO\u2093 conditions is reaction with HO\u2082, produced from reaction of OH with H\u2082O\u2082, and under high-NO\u2093 conditions, reactions with NO. Here we present the gas-phase results observed. Under low-NO\u2093 conditions the main first generation oxidation products are a number of \u03b1-pinene hydroxy hydroperoxides and pinonaldehyde, accounting for over 40% of the yield. In all, 65\u201375% of the carbon can be accounted for in the gas phase; this excludes first-generation products that enter the particle phase. We suggest that pinonaldehyde forms from RO\u2082 + HO\u2082 through an alkoxy radical channel that regenerates OH, a mechanism typically associated with acyl peroxy radicals, not alkyl peroxy radicals. The OH oxidation and photolysis of \u03b1-pinene hydroxy hydroperoxides leads to further production of pinonaldehyde, resulting in total pinonaldehyde yield from low-NO\u2093 OH oxidation of ~33%. The low-NO\u2093 OH oxidation of pinonaldehyde produces a number of carboxylic acids and peroxyacids known to be important secondary organic aerosol components. Under high-NO\u2093 conditions, pinonaldehyde was also found to be the major first-generation OH oxidation product. The high-NO\u2093 OH oxidation of pinonaldehyde did not produce carboxylic acids and peroxyacids. A number of organonitrates and peroxyacyl nitrates are observed and identified from \u03b1-pinene and pinonaldehyde.", "date": "2012-07-25", "date_type": "published", "publication": "Atmospheric Chemistry and Physics", "volume": "12", "number": "14", "publisher": "European Geosciences Union", "pagerange": "6489-6504", "id_number": "CaltechAUTHORS:20121003-090543069", "issn": "1680-7324", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20121003-090543069", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0006626" }, { "agency": "NSF", "grant_number": "AGS-1057183" }, { "agency": "Camille and Henry Dreyfus Foundation" }, { "agency": "NSF Graduate Research Fellowship" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/acp-12-6489-2012", "primary_object": { "basename": "acp-12-6489-2012-supplement.pdf", "url": "https://authors.library.caltech.edu/records/c0ebw-dz302/files/acp-12-6489-2012-supplement.pdf" }, "related_objects": [ { "basename": "acp-12-6489-2012.pdf", "url": "https://authors.library.caltech.edu/records/c0ebw-dz302/files/acp-12-6489-2012.pdf" } ], "resource_type": "article", "pub_year": "2012", "author_list": "Eddingsaas, N. C.; Loza, C. L.; et el." }, { "id": "https://authors.library.caltech.edu/records/0jfqt-qp348", "eprint_id": 33119, "eprint_status": "archive", "datestamp": "2023-08-22 06:10:16", "lastmod": "2023-10-18 18:49:03", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Beaver-M-R", "name": { "family": "Beaver", "given": "M. R." } }, { "id": "St-Clair-J-M", "name": { "family": "St. Clair", "given": "J. M." }, "orcid": "0000-0002-9367-5749" }, { "id": "Paulot-F", "name": { "family": "Paulot", "given": "F." }, "orcid": "0000-0001-7534-4922" }, { "id": "Spencer-K-M", "name": { "family": "Spencer", "given": "K. M." } }, { "id": "Crounse-J-D", "name": { "family": "Crounse", "given": "J. D." }, "orcid": "0000-0001-5443-729X" }, { "id": "LaFranchi-B-W", "name": { "family": "LaFranchi", "given": "B. W." } }, { "id": "Min-K-E", "name": { "family": "Min", "given": "K. E." } }, { "id": "Pusede-S-E", "name": { "family": "Pusede", "given": "S. E." } }, { "id": "Wooldridge-P-J", "name": { "family": "Wooldridge", "given": "P. J." } }, { "id": "Schade-G-W", "name": { "family": "Schade", "given": "G. W." } }, { "id": "Park-C", "name": { "family": "Park", "given": "C." } }, { "id": "Cohen-R-C", "name": { "family": "Cohen", "given": "R. C." }, "orcid": "0000-0001-6617-7691" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "Importance of biogenic precursors to the budget of organic nitrates: observations of multifunctional organic nitrates by CIMS and TD-LIF during BEARPEX 2009", "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: 11 November 2011; Published in Atmos. Chem. Phys. Discuss.: 4 January 2012; Revised: 23 May 2012; Accepted: 6 June 2012; Published: 3 July 2012. \n\nThis research was supported by the National Science Foundation (grants ATM-0934408 and ATM-0934345). We thank Sierra Pacific Industries for the use of their land, and the\nUniversity of California, Berkeley, Center for Forestry, Blodgett\nForest Research Station for cooperation in facilitating this research. MRB also thanks Ying Xie (US EPA) and Ellie Browne (UCB) for helpful comments on the manuscript. \n\nEdited by: J. Williams\n\nPublished - Beaver2012p19118Atmos_Chem_Phys.pdf
", "abstract": "Alkyl and multifunctional organic nitrates, molecules of the chemical form RONO_2, are products of chain terminating reactions in the tropospheric HO_x and NO_x catalytic cycles and thereby impact ozone formation locally.\nMany of the molecules in the class have lifetimes that are\nlong enough that they can be transported over large distances.\nIf the RONO_2 then decompose to deliver NO_x to remote regions they affect ozone production rates in locations distant from the original NO_x source. While measurements of total RONO_2 (\u03a3ANs) and small straight chain alkyl nitrates are routine, measurements of the specific multifunctional RONO_2 molecules that are believed to dominate the total have rarely been reported and never reported in coincidence with ambient \u03a3ANs measurements. Here we describe observations obtained during the BEARPEX 2009 experiment including \u03a3ANs and a suite of multifunctional nitrates including isoprene derived hydroxynitrates, oxidation products of those nitrates, 2-methyl-3-buten-2-ol (MBO) derived hydroxynitrates,\nand monoterpene nitrates. At the BEARPEX field site, the sum of the individual biogenically derived nitrates\naccount for two-thirds of the \u03a3ANs, confirming predictions\nof the importance of biogenic nitrates to the NO_y\nbudget. Isoprene derived nitrates, transported to the site, are a much larger fraction of the \u03a3ANs at the site than the nitrates derived from the locally emitted MBO. Evidence for\nadditional nitrates, possibly from nocturnal chemistry of isoprene and \u03b1-pinene, is presented.", "date": "2012-07-03", "date_type": "published", "publication": "Atmospheric Chemistry and Physics", "volume": "12", "number": "13", "publisher": "European Geosciences Union", "pagerange": "5773-5785", "id_number": "CaltechAUTHORS:20120813-101910446", "issn": "1680-7316", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20120813-101910446", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "ATM-0934408" }, { "agency": "NSF", "grant_number": "ATM-0934345" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/acp-12-5773-2012", "primary_object": { "basename": "Beaver2012p19118Atmos_Chem_Phys.pdf", "url": "https://authors.library.caltech.edu/records/0jfqt-qp348/files/Beaver2012p19118Atmos_Chem_Phys.pdf" }, "resource_type": "article", "pub_year": "2012", "author_list": "Beaver, M. R.; St. Clair, J. M.; et el." }, { "id": "https://authors.library.caltech.edu/records/ke5n9-1e008", "eprint_id": 47284, "eprint_status": "archive", "datestamp": "2023-08-19 11:27:21", "lastmod": "2023-10-26 20:28:03", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Oshchepkov-Sergey", "name": { "family": "Oshchepkov", "given": "Sergey" } }, { "id": "Wunch-Debra", "name": { "family": "Wunch", "given": "Debra" }, "orcid": "0000-0002-4924-0377" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "Effects of atmospheric light scattering on spectroscopic observations of greenhouse gases from space: Validation of PPDF-based CO\u2082 retrievals from GOSAT", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2012 American Geophysical Union. \n\nReceived 21 January 2012; Revised 2 April 2012; Accepted 13 May 2012; Published 23 June 2012. \n\nGOSAT is a joint effort of the Japan Aerospace Exploration Agency (JAXA), the National Institute for Environmental Studies (NIES), and the Ministry of the Environment (MOE), Japan. U.S.\nfunding for TCCON is provided by NASA's Terrestrial Ecology Program (grant NNX11AG01G), the Orbiting Carbon Observatory Program, the Atmospheric CO_2 Observations from Space (ACOS) Program, and the Department of Energy/Atmospheric Radiation Measurement (DOE/ARM) Program. The Darwin TCCON site was built at Caltech with funding from the OCO project, and is operated by the University of Wollongong, with\ntravel funds for maintenance and equipment costs funded by the OCO-2\nproject. We acknowledge funding to support Darwin and Wollongong from\nthe Australian Research Council, projects LE0668470, DP0879468,\nDP110103118 and LP0562346. Lauder TCCON measurements are funded\nby New Zealand Foundation of Research Science and Technology contracts\nC01X0204 and CO1X0406. We acknowledge financial support of the\nBia\u0142ystok and Orl\u00e9ans TCCON sites from the Senate of Bremen and EU projects\nIMECC, GEOMON and InGOS as well as maintenance and logistical\nwork provided by AeroMeteo Service (Bia\u0142ystok) and the RAMCES team\nat LSCE (Gif-sur-Yvette, France) and additional operational funding from\nthe NIES GOSAT project. The Garmisch TCCON team acknowledges funding\nby the EC-INGOS project. We acknowledge the CALIOP mission for\nobtaining the cloud data. The JRA-25/JCDAS data sets used for atmospheric\ntransport modeling were provided by the cooperative, long-term reanalysis\nproject by the Japan Meteorological Agency (JMA) and Central Research Institute of Electric Power Industry (CRIEPI). The authors thank Yasuhiro\nSasano, Director of the Center for Global Environmental Research at the\nNIES, the members of the NIES GOSAT and NASA ACOS projects, and\nthree anonymous reviewers for their helpful comments.\n\nPublished - jgrd17930.pdf
", "abstract": "This report describes a validation study of Greenhouse gases Observing Satellite (GOSAT) data processing using ground-based measurements of the Total Carbon Column Observing Network (TCCON) as reference data for column-averaged dry air mole fractions of atmospheric carbon dioxide (X_(CO\u2082)). We applied the photon path length probability density function method to validate X_(CO\u2082) retrievals from GOSAT data obtained during 22 months starting from June 2009. This method permitted direct evaluation of optical path modifications due to atmospheric light scattering that would have a negligible impact on ground-based TCCON measurements but could significantly affect gas retrievals when observing reflected sunlight from space. Our results reveal effects of optical path lengthening over Northern Hemispheric stations, essentially from May\u2013September of each year, and of optical path shortening for sun-glint observations in tropical regions. These effects are supported by seasonal trends in aerosol optical depth derived from an offline three-dimensional aerosol transport model and by cirrus optical depth derived from space-based measurements of the Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP) instrument. Removal of observations that were highly contaminated by aerosol and cloud from the GOSAT data set resulted in acceptable agreement in the seasonal variability of XCO\u2082 over each station as compared with TCCON measurements. Statistical comparisons between GOSAT and TCCON coincident measurements of CO\u2082 column abundance show a correlation coefficient of 0.85, standard deviation of 1.80 ppm, and a sub-ppm negative bias of \u22120.43 ppm for all TCCON stations. Global distributions of monthly mean retrieved X_(CO\u2082) with a spatial resolution of 2.5\u00b0 latitude \u00d7 2.5\u00b0 longitude show agreement within \u223c2.5 ppm with those predicted by the atmospheric tracer transport model.", "date": "2012-06-23", "date_type": "published", "publication": "Journal of Geophysical Research. Atmospheres", "volume": "117", "number": "D12", "publisher": "American Geophysical Union", "pagerange": "Art. No. D12305", "id_number": "CaltechAUTHORS:20140717-090533782", "issn": "2169-897X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140717-090533782", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NNX11AG01G" }, { "agency": "Department of Energy (DOE)" }, { "agency": "Australian Research Council", "grant_number": "LE0668470" }, { "agency": "Australian Research Council", "grant_number": "DP0879468" }, { "agency": "Australian Research Council", "grant_number": "DP110103118" }, { "agency": "Australian Research Council", "grant_number": "LP0562346" }, { "agency": "New Zealand Foundation of Research Science and Technology", "grant_number": "C01X0204" }, { "agency": "New Zealand Foundation for Research Science and Technology", "grant_number": "CO1X0406" }, { "agency": "Senate of Bremen" }, { "agency": "IMECC" }, { "agency": "GEOMON" }, { "agency": "InGOS" }, { "agency": "National Institute for Environmental Studies (Japan)" }, { "agency": "EC-INGOS Project" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2012JD017505", "primary_object": { "basename": "jgrd17930.pdf", "url": "https://authors.library.caltech.edu/records/ke5n9-1e008/files/jgrd17930.pdf" }, "resource_type": "article", "pub_year": "2012", "author_list": "Oshchepkov, Sergey; Wunch, Debra; et el." }, { "id": "https://authors.library.caltech.edu/records/bahrz-vzz65", "eprint_id": 32419, "eprint_status": "archive", "datestamp": "2023-08-22 05:59:11", "lastmod": "2023-10-17 23:48:20", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Crounse-J-D", "name": { "family": "Crounse", "given": "John D." }, "orcid": "0000-0001-5443-729X" }, { "id": "Knap-H-C", "name": { "family": "Knap", "given": "Hasse C." } }, { "id": "\u00d8rns\u00f8-K-B", "name": { "family": "\u00d8rns\u00f8", "given": "Kristian B." } }, { "id": "J\u00f8rgensen-S", "name": { "family": "J\u00f8rgensen", "given": "Solvejg" } }, { "id": "Paulot-F", "name": { "family": "Paulot", "given": "Fabien" }, "orcid": "0000-0001-7534-4922" }, { "id": "Kjaergaard-H-G", "name": { "family": "Kjaergaard", "given": "Henrik G." }, "orcid": "0000-0002-7275-8297" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "Atmospheric Fate of Methacrolein. 1. Peroxy Radical Isomerization Following Addition of OH and O_2", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2012 American Chemical Society. \n\nReceived: December 1, 2011; Revised: March 12, 2012; Published: March 27, 2012. \n\nWe thank N. C. Eddingsaas for the design and construction of\nthe chamber used in this work, M. R. Beaver for assistance with experiments, J. M. St. Clair for instrumental assistance, and K. M. Spencer for providing CIMS calibrations of glycolaldehyde and hydroxyacetone. We thank J. Peeters for helpful initial discussions regarding the feasibility of the 1,4-H-shift of MACR-1-OH-2-OO. We thank NASA (NNX08AD29G) and NSF (ATM-0934408), the Danish Council for Independent Research - Natural Sciences, and the Danish Center for Scientific Computing (DCSC) for funding. F.P. acknowledges support from NASA earth and space science fellowship.\n\nSupplemental Material - jp211560u_si_001.pdf
", "abstract": "Peroxy radicals formed by addition of OH and O_2 to the olefinic carbon atoms in methacrolein react with NO to form methacrolein hydroxy nitrate and hydroxyacetone. We observe that the ratio of these two compounds, however, unexpectedly decreases as the lifetime of the peroxy radical increases. We propose that this results from an isomerization involving the 1,4-H-shift of the aldehydic hydrogen atom to the peroxy group. The inferred rate (0.5 \u00b1 0.3 s^(\u20131) at T = 296 K) is consistent with estimates obtained from the potential energy surface determined by high level quantum calculations. The product, a hydroxy hydroperoxy carbonyl radical, decomposes rapidly, producing hydroxyacetone and re-forming OH. Simulations using a global chemical transport model suggest that most of the methacrolein hydroxy peroxy radicals formed in the atmosphere undergo isomerization and decomposition.", "date": "2012-06-21", "date_type": "published", "publication": "Journal of Physical Chemistry A", "volume": "116", "number": "24", "publisher": "American Chemical Society", "pagerange": "5756-5762", "id_number": "CaltechAUTHORS:20120713-101645825", "issn": "1089-5639", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20120713-101645825", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NNX08AD29G" }, { "agency": "NSF", "grant_number": "ATM-0934408" }, { "agency": "Danish Council for Independent Research Natural Sciences" }, { "agency": "Danish Center for Scientific Computing (DCSC)" }, { "agency": "NASA Earth and Space Science Fellowship" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1021/jp211560u", "primary_object": { "basename": "jp211560u_si_001.pdf", "url": "https://authors.library.caltech.edu/records/bahrz-vzz65/files/jp211560u_si_001.pdf" }, "resource_type": "article", "pub_year": "2012", "author_list": "Crounse, John D.; Knap, Hasse C.; et el." }, { "id": "https://authors.library.caltech.edu/records/xtafe-ep370", "eprint_id": 32453, "eprint_status": "archive", "datestamp": "2023-08-22 05:59:21", "lastmod": "2023-10-18 14:26:01", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Kjaergaard-H-G", "name": { "family": "Kjaergaard", "given": "Henrik G." }, "orcid": "0000-0002-7275-8297" }, { "id": "Knap-H-C", "name": { "family": "Knap", "given": "Hasse C." } }, { "id": "\u00d8rns\u00f8-K-B", "name": { "family": "\u00d8rns\u00f8", "given": "Kristian B." } }, { "id": "J\u00f8rgensen-S", "name": { "family": "J\u00f8rgensen", "given": "Solvejg" } }, { "id": "Crounse-J-D", "name": { "family": "Crounse", "given": "John D." }, "orcid": "0000-0001-5443-729X" }, { "id": "Paulot-F", "name": { "family": "Paulot", "given": "Fabien" }, "orcid": "0000-0001-7534-4922" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "Atmospheric Fate of Methacrolein. 2. Formation of Lactone and\n Implications for Organic Aerosol Production", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2012 American Chemical Society. \n\nSpecial Issue: A. R. Ravishankara Festschrift. \n\nReceived: November 11, 2011. Revised: March 27, 2012. Publication Date (Web): March 27, 2012. \n\nWe are grateful to the reviewers for suggesting the RRKM master equation analysis and to John Barker for helpful discussions regarding the MultiWell program. We thank The\nDanish Council for Independent Research - Natural Sciences,\nthe Danish Center for Scientific Computing (DCSC), NASA\n(NNX08AD29G), and NSF (ATM-0934408) for funding. F.P.\nis supported by a Ziff environmental fellowship through the\nHarvard University Center for the Environment.\n\nSupplemental Material - jp210853h_si_001.pdf
", "abstract": "We investigate the oxidation of methacryloylperoxy nitrate (MPAN) and methacrylicperoxy acid (MPAA) by the hydroxyl radical (OH) theoretically, using both density functional theory [B3LYP] and explicitly correlated coupled cluster theory [CCSD(T)-F12]. These two compounds are produced following the abstraction of a hydrogen atom from methacrolein (MACR) by the OH radical. We use a RRKM master equation analysis to estimate that the oxidation of MPAN leads to formation of hydroxymethyl\u2013methyl-\u03b1-lactone (HMML) in high yield. HMML production follows a low potential energy path from both MPAN and MPAA following addition of OH (via elimination of the NO_3 and OH from MPAN and MPAA, respectively). We suggest that the subsequent heterogeneous phase chemistry of HMML may be the route to formation of 2-methylglyceric acid, a common component of organic aerosol produced in the oxidation of methacrolein. Oxidation of acrolein, a photo-oxidation product from 1,3-butadiene, is found to follow a similar route generating hydroxymethyl-\u03b1-lactone (HML).", "date": "2012-06-21", "date_type": "published", "publication": "Journal of Physical Chemistry A", "volume": "116", "number": "24", "publisher": "American Chemical Society", "pagerange": "5763-5768", "id_number": "CaltechAUTHORS:20120716-083627902", "issn": "1089-5639", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20120716-083627902", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Danish Council for Independent Research-Natural Sciences" }, { "agency": "Danish Center for Scientific Computing (DCSC)" }, { "agency": "NASA", "grant_number": "NNX08AD29G" }, { "agency": "NSF", "grant_number": "ATM-0934408" }, { "agency": "Harvard University" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1021/jp210853h", "primary_object": { "basename": "jp210853h_si_001.pdf", "url": "https://authors.library.caltech.edu/records/xtafe-ep370/files/jp210853h_si_001.pdf" }, "resource_type": "article", "pub_year": "2012", "author_list": "Kjaergaard, Henrik G.; Knap, Hasse C.; et el." }, { "id": "https://authors.library.caltech.edu/records/txax0-grs24", "eprint_id": 47268, "eprint_status": "archive", "datestamp": "2023-08-22 05:57:57", "lastmod": "2023-10-26 20:27:20", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Galli-A", "name": { "family": "Galli", "given": "A." } }, { "id": "Butz-A", "name": { "family": "Butz", "given": "A." }, "orcid": "0000-0003-0593-1608" }, { "id": "Scheepmaker-R-A", "name": { "family": "Scheepmaker", "given": "R. A." } }, { "id": "Hasekamp-O", "name": { "family": "Hasekamp", "given": "O." } }, { "id": "Landgraf-J", "name": { "family": "Landgraf", "given": "J." }, "orcid": "0000-0002-6069-0598" }, { "id": "Tol-P", "name": { "family": "Tol", "given": "P." } }, { "id": "Wunch-D", "name": { "family": "Wunch", "given": "D." }, "orcid": "0000-0002-4924-0377" }, { "id": "Deutscher-N-M", "name": { "family": "Deutscher", "given": "N. M." }, "orcid": "0000-0002-2906-2577" }, { "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": "Griffith-D-W-T", "name": { "family": "Griffith", "given": "D. W. T." }, "orcid": "0000-0002-7986-1924" }, { "id": "Aben-I", "name": { "family": "Aben", "given": "I." } } ] }, "title": "CH_4, CO, and H_2O spectroscopy for the Sentinel-5 Precursor mission: an assessment with the Total Carbon Column Observing Network measurements", "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: 2 March 2012; Published in Atmos. Meas. Tech.; Discuss.: 13 March 2012; Revised: 18 May 2012; Accepted: 29 May 2012; Published: 19 June 2012. \n\nThis research was funded by the TROPOMI project through NSO. Research leading to these results has\nreceived funding from the European Union's Seventh Framework\nProgramme (FP7/2007-2013) under Grant Agreement no. 218793,\nand by the Dutch User Support Programme under project GOAO/\n16. A. Butz is supported by Deutsche Forschungsgemeinschaft\n(DFG) through the Emmy-Noether programme, grant BU2599/1-1\n(RemoteC). US funding for TCCON comes from NASA's Terrestrial\nEcology Program, grant number NNX11AG01G, the\nOrbiting Carbon Observatory Program, the Atmospheric CO2\nObservations from Space (ACOS) Program and the DOE/ARM\nProgram. The Darwin TCCON site was built at Caltech with funding from the OCO project, and is operated by the University\nof Wollongong, with travel funds for maintenance and equipment\ncosts funded by the OCO-2 project. We acknowledge funding to\nsupport Darwin and Wollongong from the Australian Research\nCouncil, Projects LE0668470, DP0879468, DP110103118 and\nLP0562346. ECMWF ERA Interim analyses are provided through\nhttp://data-portal.ecmwf.int/data/d/interimdaily/. TM4 modelled\nCH4 and CO concentration fields have been made available\nthrough J. F. Meirink, Royal Netherlands Meteorological Institute\n(KNMI). The CarbonTracker 2010 results have been provided\nby NOAA ESRL, Boulder, Colorado, USA from the website at\nhttp://carbontracker.noaa.gov.\n\nPublished - amt-5-1387-2012.pdf
", "abstract": "The TROPOspheric Monitoring Instrument (TROPOMI) will be part of ESA's TROPOMI will monitor methane and carbon monoxide concentrations in the Earth's atmosphere by measuring spectra of back-scattered sunlight in the short-wave infrared (SWIR). \n\nS5P will be the first satellite mission to rely uniquely on the spectral window at 4190\u20134340 cm^(\u22121) (2.3 \u03bcm) to retrieve CH_4 and CO. In this study, we investigated if the absorption features of the three relevant molecules CH_4, CO, and H_2O are adequately known. To this end, we retrieved total columns of CH_4, CO, and H_2O from absorption spectra measured by two ground-based Fourier transform spectrometers that are part of the Total Carbon Column Observing Network (TCCON). The retrieval results from the 4190\u20134340 cm^(\u22121) range at the TROPOMI resolution (0.45 cm^(\u22121)) were then compared to the CH_4 results obtained from the 6000 cm^(\u22121) region, and the CO results obtained from the 4190\u20134340 cm^(\u22121) region at the higher TCCON resolution (0.02 cm^(\u22121)). \n\nFor TROPOMI-like settings, we were able to reproduce the CH_4 columns to an accuracy of 0.3% apart from a constant bias of 1%. The CO retrieval accuracy was, through interference, systematically influenced by the shortcomings of the CH_4 and H_2O spectroscopy. In contrast to CH_4, the CO column error also varied significantly with atmospheric H_2O content. Unaddressed, this would introduce seasonal and latitudinal biases to the CO columns retrieved from TROPOMI measurements. We therefore recommend further effort from the spectroscopic community to be directed at the H_2O and CH_4 spectroscopy in the 4190\u20134340 cm^(\u22121) region.", "date": "2012-06-19", "date_type": "published", "publication": "Atmospheric Measurement Techniques", "volume": "5", "number": "6", "publisher": "European Geosciences Union", "pagerange": "1387-1398", "id_number": "CaltechAUTHORS:20140716-121007436", "issn": "1867-1381", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140716-121007436", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSO TROPOMI" }, { "agency": "European Research Council (ERC)", "grant_number": "218793" }, { "agency": "Dutch User Support Programme", "grant_number": "GO-AO/16" }, { "agency": "Deutsche Forschungsgemeinschaft (DFG)", "grant_number": "BU2599/1-1" }, { "agency": "NASA", "grant_number": "NNX11AG01G" }, { "agency": "Department of Energy (DOE)" }, { "agency": "Australian Research Council", "grant_number": "LE0668470" }, { "agency": "Australian Research Council", "grant_number": "DP087946" }, { "agency": "Australian Research Council", "grant_number": "DP110103118" }, { "agency": "Australian Research Council", "grant_number": "LP0562346" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/amt-5-1387-2012", "primary_object": { "basename": "amt-5-1387-2012.pdf", "url": "https://authors.library.caltech.edu/records/txax0-grs24/files/amt-5-1387-2012.pdf" }, "resource_type": "article", "pub_year": "2012", "author_list": "Galli, A.; Butz, A.; et el." }, { "id": "https://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.edu/records/ads5m-0h007", "eprint_id": 31694, "eprint_status": "archive", "datestamp": "2023-08-22 05:16:06", "lastmod": "2023-10-17 18:47:03", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Wolfe-G-M", "name": { "family": "Wolfe", "given": "Glenn M." }, "orcid": "0000-0001-6586-4043" }, { "id": "Crounse-J-D", "name": { "family": "Crounse", "given": "John D." }, "orcid": "0000-0001-5443-729X" }, { "id": "Parrish-J-D", "name": { "family": "Parrish", "given": "Jonathan D." } }, { "id": "St-Clair-J-M", "name": { "family": "St. Clair", "given": "Jason M." }, "orcid": "0000-0002-9367-5749" }, { "id": "Beaver-M-R", "name": { "family": "Beaver", "given": "Melinda R." } }, { "id": "Paulot-F", "name": { "family": "Paulot", "given": "Fabien" }, "orcid": "0000-0001-7534-4922" }, { "id": "Yoon-Tehshik-P", "name": { "family": "Yoon", "given": "Tehshik P." } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Keutsch-F-N", "name": { "family": "Keutsch", "given": "Frank N." } } ] }, "title": "Photolysis, OH reactivity and ozone reactivity of a proxy for isoprene-derived hydroperoxyenals (HPALDs)", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2012 Owner Societies. \n\nReceived 08 Feb 2012, Accepted 28 Mar 2012. First published on the web 29 Mar 2012. \n\nThis work was supported by the NOAA Climate and Global Change Postdoctoral Fellowship Program, administered by the University Corporation for Atmospheric Research. The authors thank NASA (NNX08AD29G), NSF (ATM-0934408 and ATM-0852406) and the Harvard University Center for the Environment for funding in support of this research. The authors also thank H. G. Kjaergaard for computation of ion-molecule collision rate parameters, M. Galloway for assistance with shipping logistics, and two anonymous reviewers for critical feedback on the manuscript.\n\nPublished - Wolfe2012p18265Physical_Chemistry_Chemical_Physics.pdf
Supplemental Material - c2cp40388a.pdf
", "abstract": "The C5-hydroperoxyenals (C5-HPALDs) are a newly-recognized class of multi-functional hydrocarbons produced during the hydroxyl radical (OH)-initiated oxidation of isoprene. Recent theoretical calculations suggest that fast photolysis of these compounds may be an important OH source in high-isoprene, low-NO regions. We report experimental constraints for key parameters of photolysis, OH reaction and ozone reaction of these compounds as derived from a closely-related, custom-synthesized C_6-HPALD. The photolysis quantum yield is 1.0 \u00b1 0.4 over the range 300\u2013400 nm, assuming an absorption cross section equal to the average of those measured for several analogous enals. The yield of OH from photolysis was determined as 1.0 \u00b1 0.8. The OH reaction rate constant is (5.1 \u00b1 1.8) \u00d7 10^(\u221211) cm^3 molecule^(\u22121) s^(\u22121) at 296 K. The ozone reaction rate constant is (1.2 \u00b1 0.2) \u00d7 10^(\u221218) cm^3 molecule^(\u22121) s^(\u22121) at 296 K. These results are consistent with previous first-principles estimates, though the nature and fate of secondary oxidation products remains uncertain. Incorporation of C5-HPALD chemistry with the above parameters in a 0-D box model, along with experimentally-constrained rates for C_5-HPALD production from isomerization of first-generation isoprene hydroxyperoxy radicals, is found to enhance modeled OH concentrations by 5\u201316% relative to the traditional isoprene oxidation mechanism for the chemical regimes of recent observational studies in rural and remote regions. This enhancement in OH will increase if C_5-HPALD photo-oxidation products also photolyze to yield additional OH or if the C_5-HPALD production rate is faster than has been observed.", "date": "2012-03-29", "date_type": "published", "publication": "Physical Chemistry Chemical Physics", "volume": "14", "number": "20", "publisher": "Royal Society of Chemistry", "pagerange": "7276-7286", "id_number": "CaltechAUTHORS:20120530-085600230", "issn": "1463-9076", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20120530-085600230", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "National Oceanic and Atmospheric Administration (NOAA)" }, { "agency": "NASA", "grant_number": "NNX08AD29G" }, { "agency": "NSF", "grant_number": "ATM-0934408" }, { "agency": "NSF", "grant_number": "ATM-0852406" }, { "agency": "Harvard University" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1039/c2cp40388a", "primary_object": { "basename": "Wolfe2012p18265Physical_Chemistry_Chemical_Physics.pdf", "url": "https://authors.library.caltech.edu/records/ads5m-0h007/files/Wolfe2012p18265Physical_Chemistry_Chemical_Physics.pdf" }, "related_objects": [ { "basename": "c2cp40388a.pdf", "url": "https://authors.library.caltech.edu/records/ads5m-0h007/files/c2cp40388a.pdf" } ], "resource_type": "article", "pub_year": "2012", "author_list": "Wolfe, Glenn M.; Crounse, John D.; et el." }, { "id": "https://authors.library.caltech.edu/records/k789r-y4c08", "eprint_id": 30066, "eprint_status": "archive", "datestamp": "2023-08-22 05:09:54", "lastmod": "2023-10-17 15:16:35", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Risi-C", "name": { "family": "Risi", "given": "Camille" }, "orcid": "0000-0002-8267-453X" }, { "id": "Frankenberg-C", "name": { "family": "Frankenberg", "given": "Christian" }, "orcid": "0000-0002-0546-5857" }, { "id": "Wunch-D", "name": { "family": "Wunch", "given": "Debra" }, "orcid": "0000-0002-4924-0377" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "Process-evaluation of tropospheric humidity simulated by general circulation models using water vapor isotopologues: 1. Comparison between models and observations", "ispublished": "pub", "full_text_status": "public", "keywords": "general circulation models; process-based evaluation; relative humidity; water isotopes", "note": "\u00a9 2012 American Geophysical Union. \n\nReceived 26 July 2011; revised 29 November 2011; accepted 30 December 2011; published 6 March 2012. \n\nThe ACE mission is supported mainly by the Canadian Space Agency. Level-1b data of MIPAS have been provided by ESA. U.S. funding for TCCON comes from NASA's Terrestrial Ecology Program, the Orbiting Carbon Observatory project and the DOE/ARM Program. The Lauder TCCON measurements are funded by New Zealand Foundation for Research, Science and Technology contracts CO1X0204 and CO1X0406. We thank J. Robinson, who acquires the FTS data at the Lauder site, and B. Connor, who was instrumental in setting up the Lauder TCCON measurements. TCCON measurements at Wollongong and Darwin are supported by Australian Research Council grant DP0879468. The Karlsruhe FTIR experiment has been funded by the Federal German Ministry of Education and Research (BMBF) via its program \"Ausbau der wissenschaftlichen Infrastruktur f\u00fcr die Klima-Initiative (HALO)\". IMK-ASF would like to thank U. Raffalski, IRF, Kiruna, for assistance with the FTIR experiment in Kiruna. Research at the University of Li\u00e9ge has primarily been supported by the A3C project funded by the Belgian Science Policy Office (BELSPO, Brussels). Emmanuel Mahieu is Research Associate with the F.R.S.-FNRS. We further acknowledge the International Foundation High Altitude Research Stations Jungfraujoch and Gornergrat (HFSJG, Bern) for supporting the facilities needed to perform the FTIR observations. The Bruker 125HR measurements at Eureka were made at the Polar Environment Atmospheric Research Laboratory (PEARL) by the Canadian Network for the Detection of Atmospheric Change (CANDAC), led by James R. Drummond, and in part by the Canadian Arctic ACE Validation Campaigns. They were supported by the Atlantic Innovation Fund/Nova Scotia Research Innovation Trust, Canada Foundation for Innovation, Canadian Foundation for Climate and Atmospheric Sciences, Canadian Space Agency, Environment Canada, Government of Canada International Polar Year funding, Natural Sciences and Engineering Research Council, Northern Scientific Training Program, Ontario Innovation Trust, Polar Continental Shelf Program, and Ontario Research Fund. The authors wish to thank Rodica Lindenmaier, Rebecca Batchelor, PEARL site manager Pierre F. Fogal, the CANDAC operators, and the staff at Environment Canada's Eureka weather station for their contributions to data acquisition, and logistical and on-site support. The mid-infrared FTIR retrievals have been performed in the framework of the project MUSICA (http://www.imk-asf.kit.edu/english/musica), which is funded by the European Research Council under the European Community's Seventh Framework Programme (FP7/2007\u20132013)/ERC grant agreement 256961. We thank the Anderson Group at Harvard University for providing ICOS and Hoxotope in situ aircraft data. We thank all SWING2 members for producing and making available their model outputs. SWING2 was supported by the Isotopic Hydrology Programme at the International Atomic Energy Agency (more information on http://people.su.se/cstur/SWING2). This work was supported by NASA Energy and Water-cycle Study (07-NEWS07-0020) and NASA Atmospheric Composition program (NNX08AR23G). We thank all reviewers for their fruitful comments.\n\nPublished - Risi2012p17722J_Geophys_Res-Atmos.pdf
Supplemental Material - jgrd17565-sup-0001-t01.txt
Supplemental Material - jgrd17565-sup-0002-t02.txt
Supplemental Material - jgrd17565-sup-0003-t03.txt
Supplemental Material - jgrd17565-sup-0004-t04.txt
Supplemental Material - jgrd17565-sup-0005-t05.txt
Supplemental Material - jgrd17565-sup-0006-t06.txt
", "abstract": "The goal of this study is to determine how H_2O and HDO measurements in water vapor can be used to detect and diagnose biases in the representation of processes controlling tropospheric humidity in atmospheric general circulation models (GCMs). We analyze a large number of isotopic data sets (four satellite, sixteen ground-based remote-sensing, five surface in situ and three aircraft data sets) that are sensitive to different altitudes throughout the free troposphere. Despite significant differences between data sets, we identify some observed HDO/H_2O characteristics that are robust across data sets and that can be used to evaluate models. We evaluate the isotopic GCM LMDZ, accounting for the effects of spatiotemporal sampling and instrument sensitivity. We find that LMDZ reproduces the spatial patterns in the lower and mid troposphere remarkably well. However, it underestimates the amplitude of seasonal variations in isotopic composition at all levels in the subtropics and in midlatitudes, and this bias is consistent across all data sets. LMDZ also underestimates the observed meridional isotopic gradient and the contrast between dry and convective tropical regions compared to satellite data sets. Comparison with six other isotope-enabled GCMs from the SWING2 project shows that biases exhibited by LMDZ are common to all models. The SWING2 GCMs show a very large spread in isotopic behavior that is not obviously related to that of humidity, suggesting water vapor isotopic measurements could be used to expose model shortcomings. In a companion paper, the isotopic differences between models are interpreted in terms of biases in the representation of processes controlling humidity.", "date": "2012-03-06", "date_type": "published", "publication": "Journal of Geophysical Research D", "volume": "117", "number": "D5", "publisher": "American Geophysical Union", "pagerange": "Art. No. D05303", "id_number": "CaltechAUTHORS:20120412-093926575", "issn": "0148-0227", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20120412-093926575", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Canadian Space Agency (CSA)" }, { "agency": "NASA" }, { "agency": "Department of Energy (DOE)" }, { "agency": "New Zealand Foundation for Research, Science and Technology", "grant_number": "CO1X0204" }, { "agency": "New Zealand Foundation for Research, Science and Technology", "grant_number": "CO1X0406" }, { "agency": "Australian Research Council", "grant_number": "DP0879468" }, { "agency": "Bundesministerium f\u00fcr Bildung und Forschung (BMBF)" }, { "agency": "Belgian Federal Science Policy Office (BELSPO)" }, { "agency": "Atlantic Innovation Fund/Nova Scotia Research Innovation Trust" }, { "agency": "Canada Foundation for Innovation" }, { "agency": "Canadian Foundation for Climate and Atmospheric Sciences" }, { "agency": "Environment Canada" }, { "agency": "Government of Canada International Polar Year" }, { "agency": "Natural Sciences and Engineering Research Council of Canada (NSERC)" }, { "agency": "Northern Scientific Training Program" }, { "agency": "Ontario Innovation Trust" }, { "agency": "Polar Continental Shelf Program" }, { "agency": "Ontario Research Fund" }, { "agency": "European Research Council (ERC)", "grant_number": "256961" }, { "agency": "International Atomic Energy Agency" }, { "agency": "NASA", "grant_number": "07-NEWS07-0020" }, { "agency": "NASA", "grant_number": "NNX08AR23G" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2011JD016621", "primary_object": { "basename": "jgrd17565-sup-0001-t01.txt", "url": "https://authors.library.caltech.edu/records/k789r-y4c08/files/jgrd17565-sup-0001-t01.txt" }, "related_objects": [ { "basename": "jgrd17565-sup-0002-t02.txt", "url": "https://authors.library.caltech.edu/records/k789r-y4c08/files/jgrd17565-sup-0002-t02.txt" }, { "basename": "jgrd17565-sup-0003-t03.txt", "url": "https://authors.library.caltech.edu/records/k789r-y4c08/files/jgrd17565-sup-0003-t03.txt" }, { "basename": "jgrd17565-sup-0004-t04.txt", "url": "https://authors.library.caltech.edu/records/k789r-y4c08/files/jgrd17565-sup-0004-t04.txt" }, { "basename": "jgrd17565-sup-0005-t05.txt", "url": "https://authors.library.caltech.edu/records/k789r-y4c08/files/jgrd17565-sup-0005-t05.txt" }, { "basename": "jgrd17565-sup-0006-t06.txt", "url": "https://authors.library.caltech.edu/records/k789r-y4c08/files/jgrd17565-sup-0006-t06.txt" }, { "basename": "Risi2012p17722J_Geophys_Res-Atmos.pdf", "url": "https://authors.library.caltech.edu/records/k789r-y4c08/files/Risi2012p17722J_Geophys_Res-Atmos.pdf" } ], "resource_type": "article", "pub_year": "2012", "author_list": "Risi, Camille; Frankenberg, Christian; et el." }, { "id": "https://authors.library.caltech.edu/records/fck90-56g57", "eprint_id": 47293, "eprint_status": "archive", "datestamp": "2023-08-22 05:08:37", "lastmod": "2023-10-26 20:28:50", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Keppel-Aleks-G", "name": { "family": "Keppel-Aleks", "given": "G." } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Washenfelder-R-A", "name": { "family": "Washenfelder", "given": "R. A." }, "orcid": "0000-0002-8106-3702" }, { "id": "Wunch-D", "name": { "family": "Wunch", "given": "D." }, "orcid": "0000-0002-4924-0377" }, { "id": "Schneider-T", "name": { "family": "Schneider", "given": "T." }, "orcid": "0000-0001-5687-2287" }, { "id": "Toon-G-C", "name": { "family": "Toon", "given": "G. C." }, "orcid": "0000-0003-4174-7541" }, { "id": "Andres-R-J", "name": { "family": "Andres", "given": "R. J." } }, { "id": "Blavier-J-F-L", "name": { "family": "Blavier", "given": "J. F." } }, { "id": "Connor-B", "name": { "family": "Connor", "given": "B." } }, { "id": "Davis-K-J", "name": { "family": "Davis", "given": "K. J." } }, { "id": "Desai-A-R", "name": { "family": "Desai", "given": "A. R." } }, { "id": "Messerschmidt-J", "name": { "family": "Messerschmidt", "given": "J." } }, { "id": "Notholt-J", "name": { "family": "Notholt", "given": "J." } }, { "id": "Roehl-C-M", "name": { "family": "Roehl", "given": "C. M." }, "orcid": "0000-0001-5383-8462" }, { "id": "Sherlock-V", "name": { "family": "Sherlock", "given": "V." } }, { "id": "Stephens-B-B", "name": { "family": "Stephens", "given": "B. B." } }, { "id": "Vay-S-A", "name": { "family": "Vay", "given": "S. A." } }, { "id": "Wofsy-S-C", "name": { "family": "Wofsy", "given": "S. C." }, "orcid": "0000-0002-3990-6737" } ] }, "title": "The imprint of surface fluxes and transport on variations in total column carbon dioxide", "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: 30 June 2011; Published in Biogeosciences Discuss.: 27 July 2011; Revised: 2 January 2012; Accepted: 9 February 2012; Published: 1 March 2012. \n\nSupport for this work from NASA Carbon Cycle Program grant NNX08AI86G is gratefully acknowledged.\nGKA acknowledges fellowships from NSF and AAUW. The\nsimulations used in this study were performed on the Caltech\nDivision of Geological and Planetary Sciences Dell Cluster. Lauder\nTCCON measurements are funded by New Zealand Foundation\nof Research Science and Technology contracts C01X0204,\nC01X0703, and C01X0406. HIPPO is supported by the National\nScience Foundation and the National Ocean and Atmosphere\nAdministration. CarbonTracker 2009 results were provided by\nNOAA ESRL, Boulder, Colorado, USA from the website at\nhttp://carbontracker.noaa.gov. LEF flux tower observations were\nmade possible with assistance from A. Andrews (NOAA), J. Thom\n(UW), D. Baumann and M. Kubiske (USFS), and R. Strand and\nJ. Ayers of the Wisconsin Educational Communications Board, and\nsupported by Department of Energy (DOE) Office of Biological\nand Environmental Research (BER) National Institute for Climatic\nChange Research (NICCR) Midwestern Region Subagreement\n050516Z19 and the National Science Foundation (NSF) Biology\nDirectorate Grant DEB-0845166. RJA was sponsored by\nUS Department of Energy, Office of Science, Biological and\nEnvironmental Research (BER) programs and performed at Oak\nRidge National Laboratory (ORNL) under US Department of\nEnergy contract DE-AC05-00OR22725. We acknowledge financial support by the Senate of Bremen and the EU projects IMECC and\nGEOmon as well as maintainance and logistical work provided by\nAeroMeteo Service (Bialystok).\n\nPublished - bg-9-875-2012.pdf
", "abstract": "New observations of the vertically integrated CO_2 mixing ratio, \u27e8CO_2\u27e9, from ground-based remote sensing show that variations in CO_2\u27e9 are primarily determined by large-scale flux patterns. They therefore provide fundamentally different information than observations made within the boundary layer, which reflect the combined influence of large-scale and local fluxes. Observations of both \u27e8CO_2\u27e9 and CO_2 concentrations in the free troposphere show that large-scale spatial gradients induce synoptic-scale temporal variations in \u27e8CO_2\u27e9 in the Northern Hemisphere midlatitudes through horizontal advection. Rather than obscure the signature of surface fluxes on atmospheric CO_2, these synoptic-scale variations provide useful information that can be used to reveal the meridional flux distribution. We estimate the meridional gradient in \u27e8CO_2\u27e9 from covariations in \u27e8CO_2\u27e9 and potential temperature, \u03b8, a dynamical tracer, on synoptic timescales to evaluate surface flux estimates commonly used in carbon cycle models. We find that simulations using Carnegie Ames Stanford Approach (CASA) biospheric fluxes underestimate both the \u27e8CO_2\u27e9 seasonal cycle amplitude throughout the Northern Hemisphere midlatitudes and the meridional gradient during the growing season. Simulations using CASA net ecosystem exchange (NEE) with increased and phase-shifted boreal fluxes better fit the observations. Our simulations suggest that climatological mean CASA fluxes underestimate boreal growing season NEE (between 45\u201365\u00b0 N) by ~40%. We describe the implications for this large seasonal exchange on inference of the net Northern Hemisphere terrestrial carbon sink.", "date": "2012-03-01", "date_type": "published", "publication": "Biogeosciences", "volume": "9", "number": "3", "publisher": "European Geosciences Union", "pagerange": "875-891", "id_number": "CaltechAUTHORS:20140717-110834015", "issn": "1726-4170", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140717-110834015", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NNX08AI86G" }, { "agency": "NSF" }, { "agency": "American Association of University Women" }, { "agency": "New Zealand Foundation of Research Science and Technology", "grant_number": "C01X0204" }, { "agency": "New Zealand Foundation of Research Science and Technology", "grant_number": "C01X0703" }, { "agency": "New Zealand Foundation of Research Science and Technology", "grant_number": "C01X0406" }, { "agency": "National Oceanic and Atmospheric Administration (NOAA)" }, { "agency": "National Institute for Climatic Change Research" }, { "agency": "Department of Energy (DOE)", "grant_number": "050516Z19" }, { "agency": "NSF", "grant_number": "DEB-0845166" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC05-00OR22725" }, { "agency": "Senate of Bremen" }, { "agency": "European Union (EU)" }, { "agency": "IMECC" }, { "agency": "GEOmon" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/bg-9-875-2012", "primary_object": { "basename": "bg-9-875-2012.pdf", "url": "https://authors.library.caltech.edu/records/fck90-56g57/files/bg-9-875-2012.pdf" }, "resource_type": "article", "pub_year": "2012", "author_list": "Keppel-Aleks, G.; Wennberg, P. O.; et el." }, { "id": "https://authors.library.caltech.edu/records/feq0b-k5d28", "eprint_id": 29796, "eprint_status": "archive", "datestamp": "2023-08-22 04:55:44", "lastmod": "2023-10-24 22:27:47", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Schneising-O", "name": { "family": "Schneising", "given": "O." } }, { "id": "Bergamaschi-P", "name": { "family": "Bergamaschi", "given": "P." } }, { "id": "Bovensmann-H", "name": { "family": "Bovensmann", "given": "H." } }, { "id": "Buchwitz-M", "name": { "family": "Buchwitz", "given": "M." } }, { "id": "Burrows-J-P", "name": { "family": "Burrows", "given": "J. P." } }, { "id": "Deutscher-N-M", "name": { "family": "Deutscher", "given": "N. M." }, "orcid": "0000-0002-2906-2577" }, { "id": "Griffith-D-W-T", "name": { "family": "Griffith", "given": "D. W. T." }, "orcid": "0000-0002-7986-1924" }, { "id": "Heymann-J", "name": { "family": "Heymann", "given": "J." } }, { "id": "Macatangay-R", "name": { "family": "Macatangay", "given": "R." } }, { "id": "Messerschmidt-J", "name": { "family": "Messerschmidt", "given": "J." } }, { "id": "Notholt-J", "name": { "family": "Notholt", "given": "J." } }, { "id": "Rettinger-M", "name": { "family": "Rettinger", "given": "M." } }, { "id": "Reuter-M", "name": { "family": "Reuter", "given": "M." } }, { "id": "Sussman-R", "name": { "family": "Sussman", "given": "R." } }, { "id": "Velazco-V-A", "name": { "family": "Velazco", "given": "V. A." }, "orcid": "0000-0002-1376-438X" }, { "id": "Warneke-T", "name": { "family": "Warneke", "given": "T." }, "orcid": "0000-0001-5185-3415" }, { "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" } ] }, "title": "Atmospheric greenhouse gases retrieved from SCIAMACHY:\n comparison to ground-based FTS measurements and model results", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2012 The 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: 18 September 2011; Published in Atmos. Chem. Phys. Discuss.: 26 October 2011; Revised: 27 January 2012; Accepted: 30 January 2012; Published: 9 February 2012. \n\nWe thank ESA and DLR for providing us with the SCIAMACHY Level 1 data and the SCIAMACHY calibration team (DLR, SRON, University of Bremen, ESA, and others) for continuously improving the quality of the spectra. TCCON data were obtained from the TCCON Data Archive, operated by the California Institute of Technology from the website at http:\n//tccon.ipac.caltech.edu/. CarbonTracker 2010 results were provided by NOAA ESRL, Boulder, Colorado, USA from the website at http://carbontracker.noaa.gov. The research leading to these results has received funding from the ESA project CARBONGASES, which is part of The Changing Earth Science Network, the ESA projects GHG-CCI, ADVANSE, and ALANIS Methane, the European Union's Seventh Framework\nProgramme (FP7/2007\u20132013) under Grant Agreement no. 218793\nand 212095 (MACC and CityZen), the DLR grant SADOS, and\nfrom the University and the State of Bremen. The Park Falls and Lamont TCCON stations are funded by NASA grants NNX11AG01G, NAG5-12247, NNG05-GD07G, and NASA's Orbiting Carbon Observatory Program. We are grateful to the DOE ARM program for technical support in Lamont and Jeff Ayers for technical support in Park Falls. The TCCON sites at Bia\u0142ystok and Orl\u00b4eans are financially supported by the Senate of Bremen and the EU projects IMECC and GEOmon.\nWe acknowledge maintenance and logistical work provided by\nAeroMeteo Service (Bia\u0142ystok) and RAMCES team at LSCE\n(Gif-sur-Yvette, France). Edited by: B. N. Duncan\n\nPublished - Schneising2012p17455Atmos_Chem_Phys.pdf
", "abstract": "SCIAMACHY onboard ENVISAT (launched in 2002) enables the retrieval of global long-term column-averaged dry air mole fractions of the two most important anthropogenic greenhouse gases carbon dioxide and methane (denoted XCO_2 and XCH_4). In order to assess the quality of the greenhouse gas data obtained with the recently introduced v2 of the scientific retrieval algorithm WFM-DOAS, we present validations with ground-based Fourier Transform Spectrometer (FTS) measurements and comparisons with model results at eight Total Carbon Column Observing Network (TCCON) sites providing realistic error estimates of the satellite data. Such validation is a prerequisite to assess the suitability of data sets for their use in inverse modelling.\n\nIt is shown that there are generally no significant differences between the carbon dioxide annual increases of SCIAMACHY and the assimilation system CarbonTracker (2.00 \u00b1 0.16 ppm yr^(\u22121) compared to 1.94 \u00b1 0.03 ppm yr\u22121 on global average). The XCO_2 seasonal cycle amplitudes derived from SCIAMACHY are typically larger than those from TCCON which are in turn larger than those from CarbonTracker. The absolute values of the northern hemispheric TCCON seasonal cycle amplitudes are closer to SCIAMACHY than to CarbonTracker and the corresponding differences are not significant when compared with SCIAMACHY, whereas they can be significant for a subset of the analysed TCCON sites when compared with CarbonTracker. At Darwin we find discrepancies of the seasonal cycle derived from SCIAMACHY compared to the other data sets which can probably be ascribed to occurrences of undetected thin clouds. Based on the comparison with the reference data, we conclude that the carbon dioxide data set can be characterised by a regional relative precision (mean standard deviation of the differences) of about 2.2 ppm and a relative accuracy (standard deviation of the mean differences) of 1.1\u20131.2 ppm for monthly average composites within a radius of 500 km.\n\nFor methane, prior to November 2005, the regional relative precision amounts to 12 ppb and the relative accuracy is about 3 ppb for monthly composite averages within the same radius. The loss of some spectral detector pixels results in a degradation of performance thereafter in the spectral range currently used for the methane column retrieval. This leads to larger scatter and lower XCH_4 values are retrieved in the tropics for the subsequent time period degrading the relative accuracy. As a result, the overall relative precision is estimated to be 17 ppb and the relative accuracy is in the range of about 10\u201320 ppb for monthly averages within a radius of 500 km.\n\nThe derived estimates show that the SCIAMACHY XCH_4 data set before November 2005 is suitable for regional source/sink determination and regional-scale flux uncertainty reduction via inverse modelling worldwide. In addition, the XCO2 monthly data potentially provide valuable information in continental regions, where there is sparse sampling by surface flask measurements.", "date": "2012-02-09", "date_type": "published", "publication": "Atmospheric Chemistry and Physics", "volume": "12", "number": "3", "publisher": "European Geosciences Union", "pagerange": "1527-1540", "id_number": "CaltechAUTHORS:20120321-101605257", "issn": "1680-7316", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20120321-101605257", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "European Space Agency (ESA)" }, { "agency": "Deutsches Zentrum f\u00fcr Luft- und Raumfahrt (DLR)" }, { "agency": "University and the State of Bremen" }, { "agency": "NASA", "grant_number": "NNX11AG01G" }, { "agency": "NASA", "grant_number": "NAG5-12247" }, { "agency": "NASA", "grant_number": "NNG05-GD07G" }, { "agency": "Department of Energy (DOE)" }, { "agency": "European Research Council (ERC)", "grant_number": "212095" }, { "agency": "European Research Council (ERC)", "grant_number": "218793" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/acp-12-1527-2012", "primary_object": { "basename": "Schneising2012p17455Atmos_Chem_Phys.pdf", "url": "https://authors.library.caltech.edu/records/feq0b-k5d28/files/Schneising2012p17455Atmos_Chem_Phys.pdf" }, "resource_type": "article", "pub_year": "2012", "author_list": "Schneising, O.; Bergamaschi, P.; et el." }, { "id": "https://authors.library.caltech.edu/records/nn1ny-es530", "eprint_id": 29804, "eprint_status": "archive", "datestamp": "2023-08-22 04:54:39", "lastmod": "2023-10-24 22:28:15", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Paulot-F", "name": { "family": "Paulot", "given": "F." }, "orcid": "0000-0001-7534-4922" }, { "id": "Henze-D-K", "name": { "family": "Henze", "given": "D. K." } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "Impact of the isoprene photochemical cascade on tropical ozone", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2012 Author(s). This work is distributed\nunder the Creative Commons Attribution 3.0 License.\nPublished by Copernicus Publications on behalf of the European Geosciences Union.\nReceived: 20 July 2011 \u2013 Published in Atmos. Chem. Phys. Discuss.: 13 September 2011.\nRevised: 22 December 2011 \u2013 Accepted: 13 January 2012 \u2013 Published: 2 February 2012.\n\nThis manuscript greatly benefited from the\ncomments of two anonymous reviewers. The authors also thank\nM. R. Beaver, J. D. Crounse and Y. Xie for helpful discussions.\nF. P. was supported by a NASA Earth and Space Science Fellowship.\nDKH was supported by the NASA New Investigator Program.\nSimulations were performed on Caltech's Division of Geological\nand Planetary Sciences Dell cluster.\n\nPublished - Paulot2012p17452Atmos_Chem_Phys.pdf
Supplemental Material - acp-12-1307-2012-supplement.pdf
", "abstract": "Tropical tropospheric ozone affects Earth's radiative forcing and the oxidative capacity of the atmosphere. Considerable work has been devoted to the study of the processes controlling its budget. Yet, large discrepancies between simulated and observed tropical tropospheric ozone remain. Here, we characterize some of the mechanisms by which the photochemistry of isoprene impacts the budget of tropical ozone. At the regional scale, we use forward sensitivity simulation to explore the sensitivity to the representation of isoprene nitrates. We find that isoprene nitrates can account for up to 70% of the local NO_x = NO+NO_2 sink. The resulting modulation of ozone can be well characterized by their net modulation of NO_x. We use adjoint sensitivity simulations to demonstrate that the oxidation of isoprene can affect ozone outside of continental regions through the transport of NO_x over near-shore regions (e.g., South Atlantic) and the oxidation of isoprene outside of the boundary layer far from its emissions regions. The latter mechanism is promoted by the simulated low boundary-layer oxidative conditions. In our simulation, ~20% of the isoprene is oxidized above the boundary layer in the tropics. Changes in the interplay between regional and global effect are discussed in light of the forecasted increase in anthropogenic emissions in tropical regions.", "date": "2012-02-02", "date_type": "published", "publication": "Atmospheric Chemistry and Physics", "volume": "12", "number": "3", "publisher": "European Geosciences Union", "pagerange": "1307-1325", "id_number": "CaltechAUTHORS:20120322-084644461", "issn": "1680-7316", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20120322-084644461", "rights": "This work is distributed\nunder the Creative Commons Attribution 3.0 License.", "funders": { "items": [ { "agency": "NASA Earth and Space Science Fellowship" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/acp-12-1307-2012", "primary_object": { "basename": "Paulot2012p17452Atmos_Chem_Phys.pdf", "url": "https://authors.library.caltech.edu/records/nn1ny-es530/files/Paulot2012p17452Atmos_Chem_Phys.pdf" }, "related_objects": [ { "basename": "acp-12-1307-2012-supplement.pdf", "url": "https://authors.library.caltech.edu/records/nn1ny-es530/files/acp-12-1307-2012-supplement.pdf" } ], "resource_type": "article", "pub_year": "2012", "author_list": "Paulot, F.; Henze, D. K.; et el." }, { "id": "https://authors.library.caltech.edu/records/p8yxd-kfe03", "eprint_id": 29825, "eprint_status": "archive", "datestamp": "2023-08-22 04:46:19", "lastmod": "2023-10-24 22:29:08", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Apel-E-C", "name": { "family": "Apel", "given": "E. C." } }, { "id": "Olson-J-R", "name": { "family": "Olson", "given": "J. R." } }, { "id": "Crawford-J-H", "name": { "family": "Crawford", "given": "J. H." } }, { "id": "Hornbrook-R-S", "name": { "family": "Hornbrook", "given": "R. S." } }, { "id": "Hills-A-J", "name": { "family": "Hills", "given": "A. J." } }, { "id": "Cantrell-C-A", "name": { "family": "Cantrell", "given": "C. A." } }, { "id": "Emmons-L-K", "name": { "family": "Emmons", "given": "L. K." } }, { "id": "Knapp-D-J", "name": { "family": "Knapp", "given": "D. J." } }, { "id": "Hall-S", "name": { "family": "Hall", "given": "S." }, "orcid": "0000-0003-3066-1937" }, { "id": "Mauldin-R-L-III", "name": { "family": "Mauldin", "given": "R. L., III" } }, { "id": "Weinheimer-A-J", "name": { "family": "Weinheimer", "given": "A. J." }, "orcid": "0000-0001-6175-8286" }, { "id": "Fried-A", "name": { "family": "Fried", "given": "A." } }, { "id": "Blake-D-R", "name": { "family": "Blake", "given": "D. R." } }, { "id": "Crounse-J-D", "name": { "family": "Crounse", "given": "J. D." }, "orcid": "0000-0001-5443-729X" }, { "id": "St-Clair-J-M", "name": { "family": "St. Clair", "given": "J. M." }, "orcid": "0000-0002-9367-5749" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Diskin-G-S", "name": { "family": "Diskin", "given": "G. S." }, "orcid": "0000-0002-3617-0269" }, { "id": "Fuelberg-H-E", "name": { "family": "Fuelberg", "given": "H. E." } }, { "id": "Wisthaler-A", "name": { "family": "Wisthaler", "given": "A." } }, { "id": "Milkoviny-T", "name": { "family": "Milkoviny", "given": "T." } }, { "id": "Brune-W", "name": { "family": "Brune", "given": "W." } }, { "id": "Riemer-D-D", "name": { "family": "Riemer", "given": "D. D." } } ] }, "title": "Impact of the deep convection of isoprene and other reactive trace species on radicals and ozone in the upper troposphere", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2012 Author(s). This work is distributed under the Creative Commons Attribution 3.0 License. \n\nReceived: 23 August 2011. Published in Atmos. Chem. Phys. Discuss.: 5 October 2011. Revised: 10 January 2012. Accepted: 12 January 2012. Published: 27 January 2012. \n\nThe authors thank the crew and support team for the NASA DC-8 aircraft, and Mary Barth, Frank Flocke and John Orlando for helpful comments and discussion. The authors gratefully acknowledge the financial support of NASA (Grant No. X08AD33G). PTR-MS measurements were supported by\nthe Austrian Research Promotion Agency (FFG-ALR) and the\nTiroler Zukunftstiftung, and were carried out with the help/support\nof M. Graus, A. Hansel and T. D. Maerk. The National Center\nfor Atmospheric Research is sponsored by the National Science\nFoundation. Any opinions, findings and conclusions or recommendations\nexpressed in the publication are those of the authors\nand do not necessarily reflect the views of the National Science\nFoundation. \n\nEdited by: J. W. Bottenheim\n\nPublished - Apel2012p17542Atmos_Chem_Phys.pdf
", "abstract": "Observations of a comprehensive suite of inorganic and organic trace gases, including non-methane hydrocarbons (NMHCs), halogenated organics and oxygenated volatile organic compounds (OVOCs), obtained from the NASA DC-8 over Canada during the ARCTAS aircraft campaign in July 2008 illustrate that convection is important for redistributing both long- and short-lived species throughout the troposphere. Convective outflow events were identified by the elevated mixing ratios of organic species in the upper troposphere relative to background conditions. Several dramatic events were observed in which isoprene and its oxidation products were detected at hundreds of pptv at altitudes higher than 8 km. Two events are studied in detail using detailed experimental data and the NASA Langley Research Center (LaRC) box model. One event had no lightning NO_x (NO + NO_2) associated with it and the other had substantial lightning NO_x (LNO_x > 1 ppbv). When convective storms transport isoprene from the boundary layer to the upper troposphere and no LNO_x is present, OH is reduced due to scavenging by isoprene, which serves to slow the chemistry, resulting in longer lifetimes for species that react with OH. Ozone and PAN production is minimal in this case. In the case where isoprene is convected and LNO_x is present, there is a large effect on the expected ensuing chemistry: isoprene exerts a dominant impact on HO_x and nitrogen-containing species; the relative contribution from other species to HO_x, such as peroxides, is insignificant. The isoprene reacts quickly, resulting in primary and secondary products, including formaldehyde and methyl glyoxal. The model predicts enhanced production of alkyl nitrates (ANs) and peroxyacyl nitrate compounds (PANs). PANs persist because of the cold temperatures of the upper troposphere resulting in a large change in the NO_x mixing ratios which, in turn, has a large impact on the HO_x chemistry. Ozone production is substantial during the first few hours following the convection to the UT, resulting in a net gain of approximately 10 ppbv compared to the modeled scenario in which LNO_x is present but no isoprene is present aloft.", "date": "2012-01-27", "date_type": "published", "publication": "Atmospheric Chemistry and Physics", "volume": "12", "number": "2", "publisher": "European Geosciences Union", "pagerange": "1135-1150", "id_number": "CaltechAUTHORS:20120323-112554276", "issn": "1680-7316", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20120323-112554276", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "X08AD33G" }, { "agency": "Austrian Research Promotion Agency (FFG-ALR)" }, { "agency": "Tiroler Zukunftstiftung" }, { "agency": "NSF" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/acp-12-1135-2012", "primary_object": { "basename": "Apel2012p17542Atmos_Chem_Phys.pdf", "url": "https://authors.library.caltech.edu/records/p8yxd-kfe03/files/Apel2012p17542Atmos_Chem_Phys.pdf" }, "resource_type": "article", "pub_year": "2012", "author_list": "Apel, E. C.; Olson, J. R.; et el." }, { "id": "https://authors.library.caltech.edu/records/ghz98-4ax32", "eprint_id": 47269, "eprint_status": "archive", "datestamp": "2023-08-19 09:34:35", "lastmod": "2023-10-20 21:53:28", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "O'Dell-C-W", "name": { "family": "O'Dell", "given": "C. W." } }, { "id": "Connor-B", "name": { "family": "Connor", "given": "B." } }, { "id": "Boesch-H", "name": { "family": "B\u00f6sch", "given": "H." }, "orcid": "0000-0003-3944-9879" }, { "id": "O'Brien-D", "name": { "family": "O'Brien", "given": "D." } }, { "id": "Frankenberg-C", "name": { "family": "Frankenberg", "given": "C." }, "orcid": "0000-0002-0546-5857" }, { "id": "Castano-R", "name": { "family": "Castano", "given": "R." } }, { "id": "Christi-M", "name": { "family": "Christi", "given": "M." } }, { "id": "Crisp-D", "name": { "family": "Crisp", "given": "D." }, "orcid": "0000-0002-4573-9998" }, { "id": "Eldering-A", "name": { "family": "Eldering", "given": "A." }, "orcid": "0000-0003-1080-9922" }, { "id": "Fisher-B", "name": { "family": "Fisher", "given": "B." } }, { "id": "Gunson-M", "name": { "family": "Gunson", "given": "M." } }, { "id": "McDuffie-J", "name": { "family": "McDuffie", "given": "J." } }, { "id": "Miller-C-E", "name": { "family": "Miller", "given": "C. E." }, "orcid": "0000-0002-9380-4838" }, { "id": "Natraj-V", "name": { "family": "Natraj", "given": "V." }, "orcid": "0000-0003-3154-9429" }, { "id": "Oyafuso-F", "name": { "family": "Oyafuso", "given": "F." }, "orcid": "0000-0002-8862-8737" }, { "id": "Polonsky-I", "name": { "family": "Polonsky", "given": "I." } }, { "id": "Smyth-M", "name": { "family": "Smyth", "given": "M." } }, { "id": "Taylor-T", "name": { "family": "Taylor", "given": "T." } }, { "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": "Wunch-D", "name": { "family": "Wunch", "given": "D." }, "orcid": "0000-0002-4924-0377" } ] }, "title": "The ACOS CO_2 retrieval algorithm \u2013 Part 1: Description and validation against synthetic observations", "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\nThe authors wish to thank two anonymous reviewers for their constructive suggestions and insightful comments. We would like to thank several colleagues for work they have done that has helped this project: Bashwar Sen for early algorithm management, Linda Brown for spectroscopy development, Rob Spurr for help with the radiative transfer, Lukas Mandrake for GOSAT data analysis, and Ross Salawitch for many useful discussions. A portion of the 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. The Colorado State University contributions to this work were carried out under NASA contract 1380533.\n\nWe would like to inform you that there were two mistakes\nin the author list of this manuscript. The initial of the author\nEldering was wrong and the author Crisp was missing in the\nauthor list. Above you will find the correct author list.\n\nPublished - amt-5-99-2012.pdf
Erratum - amt-5-193-2012.pdf
", "abstract": "This work describes the NASA Atmospheric CO_2 Observations from Space (ACOS) X_(CO_2) retrieval algorithm, and its performance on highly realistic, simulated observations. These tests, restricted to observations over land, are used to evaluate retrieval errors in the face of realistic clouds and aerosols, polarized non-Lambertian surfaces, imperfect meteorology, and uncorrelated instrument noise. We find that post-retrieval filters are essential to eliminate the poorest retrievals, which arise primarily due to imperfect cloud screening. The remaining retrievals have RMS errors of approximately 1 ppm. Modeled instrument noise, based on the Greenhouse Gases Observing SATellite (GOSAT) in-flight performance, accounts for less than half the total error in these retrievals. A small fraction of unfiltered clouds, particularly thin cirrus, lead to a small positive bias of ~0.3 ppm. Overall, systematic errors due to imperfect characterization of clouds and aerosols dominate the error budget, while errors due to other simplifying assumptions, in particular those related to the prior meteorological fields, appear small.", "date": "2012-01-11", "date_type": "published", "publication": "Atmospheric Measurement Techniques", "volume": "5", "number": "1", "publisher": "European Geosciences Union", "pagerange": "99-121", "id_number": "CaltechAUTHORS:20140716-141221563", "issn": "1867-1381", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140716-141221563", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "1380533" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/amt-5-99-2012", "primary_object": { "basename": "amt-5-193-2012.pdf", "url": "https://authors.library.caltech.edu/records/ghz98-4ax32/files/amt-5-193-2012.pdf" }, "related_objects": [ { "basename": "amt-5-99-2012.pdf", "url": "https://authors.library.caltech.edu/records/ghz98-4ax32/files/amt-5-99-2012.pdf" } ], "resource_type": "article", "pub_year": "2012", "author_list": "O'Dell, C. W.; Connor, B.; et el." }, { "id": "https://authors.library.caltech.edu/records/xbx3y-a8y04", "eprint_id": 29577, "eprint_status": "archive", "datestamp": "2023-08-22 04:41:40", "lastmod": "2023-10-24 22:18:41", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Wespes-C", "name": { "family": "Wespes", "given": "C." } }, { "id": "Emmons-L", "name": { "family": "Emmons", "given": "L." } }, { "id": "Edwards-D-P", "name": { "family": "Edwards", "given": "D. P." } }, { "id": "Hannigan-J", "name": { "family": "Hannigan", "given": "J." } }, { "id": "Hurtmans-D", "name": { "family": "Hurtmans", "given": "D." } }, { "id": "Saunois-M", "name": { "family": "Saunois", "given": "M." } }, { "id": "Coheur-P-F", "name": { "family": "Coheur", "given": "P. -F." } }, { "id": "Clerbaux-C", "name": { "family": "Clerbaux", "given": "C." } }, { "id": "Coffey-M-T", "name": { "family": "Coffey", "given": "M. T." } }, { "id": "Batchelor-R-L", "name": { "family": "Batchelor", "given": "R. L." } }, { "id": "Lindenmaier-R", "name": { "family": "Lindenmaier", "given": "R." } }, { "id": "Strong-K", "name": { "family": "Strong", "given": "K." } }, { "id": "Weinheimer-A-J", "name": { "family": "Weinheimer", "given": "A. J." }, "orcid": "0000-0001-6175-8286" }, { "id": "Nowak-J-B", "name": { "family": "Nowak", "given": "J. B." } }, { "id": "Ryerson-T-B", "name": { "family": "Ryerson", "given": "T. B." }, "orcid": "0000-0003-2800-7581" }, { "id": "Crounse-J-D", "name": { "family": "Crounse", "given": "J. D." }, "orcid": "0000-0001-5443-729X" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "Analysis of ozone and nitric acid in spring and summer Arctic pollution using aircraft, ground-based, satellite observations and MOZART-4 model: source attribution and partitioning", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2012 Author(s). This work is distributed under the Creative Commons Attribution 3.0 License..\n\nReceived: 13 July 2011; Published in Atmos. Chem. Phys. Discuss.: 22 August 2011; Revised: 12 December 2011; Accepted: 14 December 2011; Published: 4 January 2012.\n\nThe National Center for Atmospheric Research is supported by the National Science Foundation. The NCAR FTS observation program at Thule, GR is supported under\ncontract by the National Aeronautics and Space Administration (NASA). This work is also supported by the NSF Office of Polar Programs (OPP). We wish to thank the Danish Meteorological Institute for support at the Thule site. The PEARL Bruker 125HR measurements at Eureka were made by the Canadian Network for the Detection of Atmospheric Change (CANDAC), led by James R. Drummond, and in part by the Canadian Arctic ACE Validation Campaigns, led by Kaley A. Walker. They were supported by the Atlantic Innovation Fund/Nova Scotia Research Innovation Trust, Canada Foundation for Innovation, Canadian Foundation\nfor Climate and Atmospheric Sciences, Canadian Space Agency,\nEnvironment Canada, Government of Canada International Polar\nYear funding, Natural Sciences and Engineering Research Council, Northern Scientific Training Program, Ontario Innovation Trust, Polar Continental Shelf Program, and Ontario Research Fund. The authors wish to thank PEARL site manager Pierre F. Fogal, the CANDAC operators, and the staff at Environment Canada's Eureka weather station for logistical and on-site support. IASI has been developed and built under the responsibility of the Centre National\nd'Etudes Spatiales (CNES, France). It is flown onboard the Metop satellites as part of the EUMETSAT Polar System. The IASI L1 data are received through the EUMETCast near real time data distribution service. P. F. Coheur is Research Associate (Chercheur Qualifi\u00e9) with F.R.S.-FNRS. The research in Belgium was funded by the F.R.S.-FNRS (M.I.S. nF.4511.08), the Belgian State Federal Office for Scientific, Technical and Cultural Affairs and the\nEuropean Space Agency (ESA-Prodex arrangements). Financial\nsupport by the 'Actions de Recherche Concert\u00e9es' (Communaut\u00e9 Fran\u00e7aise de Belgique) is also acknowledged. The research in France is supported by CNES. This research has been supported by NASA's Tropospheric Chemistry Program (ARCTAS) under grant NNX08AD22G, NNX08AD29G, and NNX07AL57G.\n\nPublished - Wespes2012p17355Atmos_Chem_Phys.pdf
", "abstract": "In this paper, we analyze tropospheric O_3 together with HNO_3 during the POLARCAT (Polar Study using Aircraft, Remote Sensing, Surface Measurements and Models, of Climate, Chemistry, Aerosols, and Transport) program, combining observations and model results. Aircraft observations from the NASA ARCTAS (Arctic Research of the Composition of the Troposphere from Aircraft and Satellites) and NOAA ARCPAC (Aerosol, Radiation and Cloud Processes affecting Arctic Climate) campaigns during spring and summer of 2008 are used together with the Model for Ozone and Related Chemical Tracers, version 4 (MOZART-4) to assist in the interpretation of the observations in terms of the source attribution and transport of O_3 and HNO_3 into the Arctic (north of 60\u00b0 N). The MOZART-4 simulations reproduce the aircraft observations generally well (within 15%), but some discrepancies in the model are identified and discussed. The observed correlation of O_3 with HNO_3 is exploited to evaluate the MOZART-4 model performance for different air mass types (fresh plumes, free troposphere and stratospheric-contaminated air masses).\n\nBased on model simulations of O_3 and HNO_3 tagged by source type and region, we find that the anthropogenic pollution from the Northern Hemisphere is the dominant source of O3 and HNO3 in the Arctic at pressures greater than 400 hPa, and that the stratospheric influence is the principal contribution at pressures less 400 hPa. During the summer, intense Russian fire emissions contribute some amount to the tropospheric columns of both gases over the American sector of the Arctic. North American fire emissions (California and Canada) also show an important impact on tropospheric ozone in the Arctic boundary layer.\n\nAdditional analysis of tropospheric O_3 measurements from ground-based FTIR and from the IASI satellite sounder made at the Eureka (Canada) and Thule (Greenland) polar sites during POLARCAT has been performed using the tagged contributions. It demonstrates the capability of these instruments for observing pollution at northern high latitudes. Differences between contributions from the sources to the tropospheric columns as measured by FTIR and IASI are discussed in terms of vertical sensitivity associated with these instruments. The first analysis of O_3 tropospheric columns observed by the IASI satellite instrument over the Arctic is also provided. Despite its limited vertical sensitivity in the lowermost atmospheric layers, we demonstrate that IASI is capable of detecting low-altitude pollution transported into the Arctic with some limitations.", "date": "2012-01-04", "date_type": "published", "publication": "Atmospheric Chemistry and Physics", "volume": "12", "number": "1", "publisher": "European Geosciences Union", "pagerange": "237-259", "id_number": "CaltechAUTHORS:20120305-121701322", "issn": "1680-7316", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20120305-121701322", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF" }, { "agency": "Atlantic Innovation Fund/Nova Scotia Research Innovation Trust" }, { "agency": "Canada Foundation for Innovation" }, { "agency": "Canadian Foundation for Climate and Atmospheric Sciences" }, { "agency": "Canadian Space Agency (CSA)" }, { "agency": "Environment Canada" }, { "agency": "Government of Canada International Polar Year" }, { "agency": "Natural Sciences and Engineering Research Council of Canada (NSERC)" }, { "agency": "Northern Scientific Training Program" }, { "agency": "Ontario Innovation Trust" }, { "agency": "Polar Continental Shelf Program" }, { "agency": "Ontario Research Fund" }, { "agency": "F.R.S.-FNRS", "grant_number": "M.I.S. nF.4511.08" }, { "agency": "Belgian State Federal Office for Scientific, Technical and Cultural Affairs" }, { "agency": "European Space Agency (ESA-Prodex arrangements)" }, { "agency": "Actions de Recherche Concert\u00e9es (Communaut\u00e9 Fran\u00e7aise de Belgique)" }, { "agency": "Centre National d'\u00c9tudes Spatiales (CNES)" }, { "agency": "NASA", "grant_number": "NNX08AD22G" }, { "agency": "NASA", "grant_number": "NNX08AD29G" }, { "agency": "NASA", "grant_number": "NNX07AL57G" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/acp-12-237-2012", "primary_object": { "basename": "Wespes2012p17355Atmos_Chem_Phys.pdf", "url": "https://authors.library.caltech.edu/records/xbx3y-a8y04/files/Wespes2012p17355Atmos_Chem_Phys.pdf" }, "resource_type": "article", "pub_year": "2012", "author_list": "Wespes, C.; Emmons, L.; et el." }, { "id": "https://authors.library.caltech.edu/records/ptdt2-fnp52", "eprint_id": 29138, "eprint_status": "archive", "datestamp": "2023-08-22 04:28:09", "lastmod": "2023-10-24 18:23:34", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Chevalier-F", "name": { "family": "Chevalier", "given": "F." } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P." }, "orcid": "0000-0002-6126-3854" }, { "id": "Wunch-D", "name": { "family": "Wunch", "given": "D." }, "orcid": "0000-0002-4924-0377" } ] }, "title": "Global CO_2 fluxes inferred from surface air-sample measurements and from TCCON retrievals of the CO_2 total column", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2011 by the American Geophysical Union. \n\nReceived 6 October 2011; revised 11 November 2011; accepted 20 November 2011; published 29 December 2011. \n\nTCCON data were obtained from the\nTCCON Data Archive, operated by the California Institute of Technology\nfrom the website at http://tccon.ipac.caltech.edu/. This work was performed\nusing HPC resources of DSM-CCRT and of [CCRT/CINES/IDRIS] under\nthe allocation 2011-t2011012201 made by GENCI (Grand Equipement\nNational de Calcul Intensif). It was co-funded by the European Commission\nunder the EU Seventh Research Framework Programme (grants agreements\n218793, MACC, and 212196, COCOS). Support for TCCON is provided by\nmany national research support organizations that are listed on the TCCON\nweb site. The authors are very grateful to the many people involved in the\nsurface and aircraft measurement and in the archiving of these data.\nThe Editor thanks two anonymous reviewers for their assistance in\nevaluating this paper.\n\nPublished - Chevallier2011p17023Geophys_Res_Lett.pdf
", "abstract": "We present the first estimate of the global distribution of CO_2 surface fluxes from 14 stations of the Total Carbon Column Observing Network (TCCON). The evaluation of this inversion is based on 1) comparison with the fluxes from a classical inversion of surface air-sample-measurements, and 2) comparison of CO_2 mixing ratios calculated from the inverted fluxes with independent aircraft measurements made during the two years analyzed here, 2009 and 2010. The former test shows similar seasonal cycles in the northern hemisphere and consistent regional carbon budgets between inversions from the two datasets, even though the TCCON inversion appears to be less precise than the classical inversion. The latter test confirms that the TCCON inversion has improved the quality (i.e., reduced the uncertainty) of the surface fluxes compared to the assumed or prior fluxes. The consistency between the surface-air-sample-based and the TCCON-based inversions despite remaining flaws in transport models opens the possibility of increased accuracy and robustness of flux inversions based on the combination of both data sources and confirms the usefulness of space-borne monitoring of the CO_2 column.", "date": "2011-12-29", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "38", "publisher": "American Geophysical Union", "pagerange": "Art. No. L24810", "id_number": "CaltechAUTHORS:20120203-154119565", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20120203-154119565", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "European Research Council (ERC)", "grant_number": "218793" }, { "agency": "European Research Council (ERC)", "grant_number": "212196" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2011GL049899", "primary_object": { "basename": "Chevallier2011p17023Geophys_Res_Lett.pdf", "url": "https://authors.library.caltech.edu/records/ptdt2-fnp52/files/Chevallier2011p17023Geophys_Res_Lett.pdf" }, "resource_type": "article", "pub_year": "2011", "author_list": "Chevalier, F.; Wennberg, P.; et el." }, { "id": "https://authors.library.caltech.edu/records/j37bb-d7y02", "eprint_id": 28989, "eprint_status": "archive", "datestamp": "2023-08-22 04:27:38", "lastmod": "2023-10-24 18:17:40", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Mu-M", "name": { "family": "Mu", "given": "M." } }, { "id": "Randerson-J-T", "name": { "family": "Randerson", "given": "J. T." }, "orcid": "0000-0001-6559-7387" }, { "id": "van-der-Werf-G-R", "name": { "family": "van der Werf", "given": "G. R." } }, { "id": "Giglio-L", "name": { "family": "Giglio", "given": "L." } }, { "id": "Kasibhatla-P", "name": { "family": "Kasibhatla", "given": "P." } }, { "id": "Morton-D", "name": { "family": "Morton", "given": "D." } }, { "id": "Collatz-G-J", "name": { "family": "Collatz", "given": "G. J." } }, { "id": "DeFries-R-S", "name": { "family": "DeFries", "given": "R. S." } }, { "id": "Hyer-E-J", "name": { "family": "Hyer", "given": "E. J." } }, { "id": "Prins-E-M", "name": { "family": "Prins", "given": "E. M." } }, { "id": "Griffith-D-W-T", "name": { "family": "Griffith", "given": "D. W. T." }, "orcid": "0000-0002-7986-1924" }, { "id": "Wunch-D", "name": { "family": "Wunch", "given": "D." }, "orcid": "0000-0002-4924-0377" }, { "id": "Toon-G-C", "name": { "family": "Toon", "given": "G. C." }, "orcid": "0000-0003-4174-7541" }, { "id": "Sherlock-V", "name": { "family": "Sherlock", "given": "V." } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "Daily and 3\u2010hourly variability in global fire emissions and consequences for atmospheric model predictions of carbon monoxide", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2011 the American Geophysical Union. \n\nReceived 12 May 2011; revised 23 September 2011; accepted 18 October 2011; published 24 December 2011. \n\nThis research was supported by NASA grants NNX08AF64G and NNX10AT83G and the EU Seventh Research Framework Programme (MACC project, contract 218793). The time series described here is publicly available on the Global Fire Emissions Database server (www.globalfiredata.org). We thank E. Lyons for contributing to the development of the daily fire emissions time series. E. J. Hyer and E. Prins acknowledge support from the NASA Interdisciplinary Studies Program. U.S.\nfunding for TCCON comes from NASA's Terrestrial Ecology Program (NNX08A186G), the Orbiting Carbon Observatory Program (NAS7\u201303001), the DOE/ARM Program and the Atmospheric CO2 Observations from Space Program. Some of the research described in this paper was performed at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration. The Lauder TCCON measurements were funded by New Zealand Foundation for Research, Science and Technology contracts CO1X0204 and CO1X0406. We thank B. Connor and J. Robinson for their contributions to the Lauder CO time series.\n\nPublished - Mu2011p16828J_Geophys_Res-Atmos.pdf
", "abstract": "Attribution of the causes of atmospheric trace gas and aerosol variability often requires the use of high resolution time series of anthropogenic and natural emissions inventories. Here we developed an approach for representing synoptic- and diurnal-scale temporal variability in fire emissions for the Global Fire Emissions Database version 3 (GFED3). We disaggregated monthly GFED3 emissions during 2003\u20132009 to a daily time step using Moderate Resolution Imaging Spectroradiometer (MODIS)-derived measurements of active fires from Terra and Aqua satellites. In parallel, mean diurnal cycles were constructed from Geostationary Operational Environmental Satellite (GOES) Wildfire Automated Biomass Burning Algorithm (WF_ABBA) active fire observations. Daily variability in fires varied considerably across different biomes, with short but intense periods of daily emissions in boreal ecosystems and lower intensity (but more continuous) periods of burning in savannas. These patterns were consistent with earlier field and modeling work characterizing fire behavior dynamics in different ecosystems. On diurnal timescales, our analysis of the GOES WF_ABBA active fires indicated that fires in savannas, grasslands, and croplands occurred earlier in the day as compared to fires in nearby forests. Comparison with Total Carbon Column Observing Network (TCCON) and Measurements of Pollution in the Troposphere (MOPITT) column CO observations provided evidence that including daily variability in emissions moderately improved atmospheric model simulations, particularly during the fire season and near regions with high levels of biomass burning. The high temporal resolution estimates of fire emissions developed here may ultimately reduce uncertainties related to fire contributions to atmospheric trace gases and aerosols. Important future directions include reconciling top-down and bottom up estimates of fire radiative power and integrating burned area and active fire time series from multiple satellite sensors to improve daily emissions estimates.", "date": "2011-12-24", "date_type": "published", "publication": "Journal of Geophysical Research D", "volume": "116", "publisher": "American Geophysical Union", "pagerange": "Art. No. D24303", "id_number": "CaltechAUTHORS:20120127-072000089", "issn": "0148-0227", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20120127-072000089", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NNX08AF64G" }, { "agency": "NASA", "grant_number": "NNX10AT83G" }, { "agency": "EU Seventh Research Framework Programme", "grant_number": "MACC-218793" }, { "agency": "NASA", "grant_number": "NNX08A186G" }, { "agency": "NASA", "grant_number": "NAS7-03001" }, { "agency": "Department of Energy (DOE)" }, { "agency": "New Zealand Foundation for Research Science and Technology", "grant_number": "CO1X0204" }, { "agency": "New Zealand Foundation for Research Science and Technology", "grant_number": "CO1X0406" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2011JD016245", "primary_object": { "basename": "Mu2011p16828J_Geophys_Res-Atmos.pdf", "url": "https://authors.library.caltech.edu/records/j37bb-d7y02/files/Mu2011p16828J_Geophys_Res-Atmos.pdf" }, "resource_type": "article", "pub_year": "2011", "author_list": "Mu, M.; Randerson, J. T.; et el." }, { "id": "https://authors.library.caltech.edu/records/tb0b8-1gc16", "eprint_id": 29789, "eprint_status": "archive", "datestamp": "2023-08-22 04:27:17", "lastmod": "2023-10-24 22:27:22", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Hecobian-A", "name": { "family": "Hecobian", "given": "A." } }, { "id": "Liu-Z", "name": { "family": "Liu", "given": "Z" } }, { "id": "Hennigan-C-J", "name": { "family": "Hennigan", "given": "C. J." } }, { "id": "Huey-L-G", "name": { "family": "Huey", "given": "L. G." }, "orcid": "0000-0002-0518-7690" }, { "id": "Jimenez-J-L", "name": { "family": "Jimenez", "given": "J. L." }, "orcid": "0000-0001-6203-1847" }, { "id": "Cubison-M-J", "name": { "family": "Cubison", "given": "M. J." } }, { "id": "Vay-S", "name": { "family": "Vay", "given": "S." } }, { "id": "Diskin-G-S", "name": { "family": "Diskin", "given": "G. S." }, "orcid": "0000-0002-3617-0269" }, { "id": "Sachse-G-W", "name": { "family": "Sachse", "given": "G. W." } }, { "id": "Wisthaler-A", "name": { "family": "Wisthaler", "given": "A." } }, { "id": "Mikoviny-T", "name": { "family": "Mikoviny", "given": "T." } }, { "id": "Weinheimer-A-J", "name": { "family": "Weinheimer", "given": "A. J." }, "orcid": "0000-0001-6175-8286" }, { "id": "Liao-J", "name": { "family": "Liao", "given": "J." } }, { "id": "Knapp-J", "name": { "family": "Knapp", "given": "J." } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" }, { "id": "K\u00fcrten-A", "name": { "family": "K\u00fcrten", "given": "A." }, "orcid": "0000-0002-8955-4450" }, { "id": "Crounse-J-D", "name": { "family": "Crounse", "given": "J. D." }, "orcid": "0000-0001-5443-729X" }, { "id": "St-Clair-J-M", "name": { "family": "St. Clair", "given": "J." }, "orcid": "0000-0002-9367-5749" }, { "id": "Wang-Y", "name": { "family": "Wang", "given": "Y." } }, { "id": "Weber-R-J", "name": { "family": "Weber", "given": "R. J." } } ] }, "title": "Comparison of chemical characteristics of 495 biomass burning plumes intercepted by the NASA DC-8 aircraft during the ARCTAS/CARB-2008 field campaign", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2011 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: 6 June 2011. Published in Atmos. Chem. Phys. Discuss.: 30 June 2011. Revised: 10 November 2011. Accepted: 9 December 2011. Published: 22 December 2011. \n\nA. H. would like to thank the NASA DC-8 crew for their assistance in making WSOC measurements on the airplane. A. W. and T. M. acknowledge financial and logistical support\nfrom the \u00d6sterreichische Forschungs\u00f6rderungsgesellschaft,\nthe Tiroler Zukunftsstifung, Armin Hansel and Tilmann D. M\u00e4rk.\nMJC and JLJ were supported by NASA NNX08AD39G. This work\nwas supported by the NASA Tropospheric Chemistry Program\nunder grant number NNX08AH80G.\n\nPublished - Hecobian2011p17449Atmos_Chem_Phys.pdf
", "abstract": "This paper compares measurements of gaseous and particulate emissions from a wide range of biomass-burning plumes intercepted by the NASA DC-8 research aircraft during the three phases of the ARCTAS-2008 experiment: ARCTAS-A, based out of Fairbanks, Alaska, USA (3 April to 19 April 2008); ARCTAS-B based out of Cold Lake, Alberta, Canada (29 June to 13 July 2008); and ARCTAS-CARB, based out of Palmdale, California, USA (18 June to 24 June 2008). Approximately 500 smoke plumes from biomass burning emissions that varied in age from minutes to days were segregated by fire source region and urban emission influences. The normalized excess mixing ratios (NEMR) of gaseous (carbon dioxide, acetonitrile, hydrogen cyanide, toluene, benzene, methane, oxides of nitrogen and ozone) and fine aerosol particulate components (nitrate, sulfate, ammonium, chloride, organic aerosols and water soluble organic carbon) of these plumes were compared. A detailed statistical analysis of the different plume categories for different gaseous and aerosol species is presented in this paper.\nThe comparison of NEMR values showed that CH4 concentrations were higher in air-masses that were influenced by urban emissions. Fresh biomass burning plumes mixed with urban emissions showed a higher degree of oxidative processing in comparison with fresh biomass burning only plumes. This was evident in higher concentrations of inorganic aerosol components such as sulfate, nitrate and ammonium, but not reflected in the organic components. Lower NOx NEMRs combined with high sulfate, nitrate and ammonium NEMRs in aerosols of plumes subject to long-range transport, when comparing all plume categories, provided evidence of advanced processing of these plumes.", "date": "2011-12-22", "date_type": "published", "publication": "Atmospheric Chemistry and Physics", "volume": "11", "number": "24", "publisher": "European Geosciences Union", "pagerange": "13325-13337", "id_number": "CaltechAUTHORS:20120321-084549058", "issn": "1680-7316", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20120321-084549058", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "\u00d6sterreichische Forschungs\u00f6rderungsgesellschaft" }, { "agency": "NASA", "grant_number": "NNX08AD39G" }, { "agency": "NASA", "grant_number": "NNX08AH80G" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/acp-11-13325-2011", "primary_object": { "basename": "Hecobian2011p17449Atmos_Chem_Phys.pdf", "url": "https://authors.library.caltech.edu/records/tb0b8-1gc16/files/Hecobian2011p17449Atmos_Chem_Phys.pdf" }, "resource_type": "article", "pub_year": "2011", "author_list": "Hecobian, A.; Liu, Z; et el." }, { "id": "https://authors.library.caltech.edu/records/nekf7-8fa62", "eprint_id": 55046, "eprint_status": "archive", "datestamp": "2023-08-22 04:21:06", "lastmod": "2023-10-20 21:17:14", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Wunch-D", "name": { "family": "Wunch", "given": "D." }, "orcid": "0000-0002-4924-0377" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Toon-G-C", "name": { "family": "Toon", "given": "G. C." }, "orcid": "0000-0003-4174-7541" }, { "id": "Frankenberg-C", "name": { "family": "Frankenberg", "given": "C." }, "orcid": "0000-0002-0546-5857" }, { "id": "Keppel-Aleks-G", "name": { "family": "Keppel-Aleks", "given": "G." } }, { "id": "Roehl-C-M", "name": { "family": "Roehl", "given": "C. M." }, "orcid": "0000-0001-5383-8462" } ] }, "title": "A method for evaluating bias in global measurements of CO_2 total columns from space", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2011 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: 28 June 2011 \u2013 Published in Atmos. Chem. Phys. Discuss.: 22 July 2011; Revised: 21 November 2011 \u2013 Accepted: 24 November 2011 \u2013 Published: 9 December 2011.\n\nThe authors wish to thank Sergey Oshchepkov, Peter Rayner, editor Ilse Aben and an anonymous reviewer for insightful and constructive comments and suggestions. We had enlightening discussions with Hiroshi Suto (JAXA) about the apparent time-dependent drift in the ACOS-GOSAT data. GOSAT spectra were kindly provided to the California Institute of Technology through an RA agreement with JAXA, NIES and the MOE. US funding for TCCON comes from NASA's Terrestrial Ecology Program, grant number NNX11AG01G, the Orbiting\nCarbon Observatory Program, the Atmospheric CO2 Observations from Space (ACOS) Program and the DOE/ARM Program. The Darwin TCCON site was built at Caltech with funding from the OCO project, and is operated by the University of Wollongong, with travel funds for maintenance and equipment costs funded by the OCO-2 project. We acknowledge funding to support Darwin and Wollongong from the Australian Research Council, Projects LE0668470, DP0879468, DP110103118 and LP0562346. Lauder TCCON measurements are funded by New Zealand Foundation of Research Science and Technology contracts C01X0204 and CO1X0406. We acknowledge financial support of the Bia\u0142ystok and Orl\u00e9ans TCCON sites from the Senate of Bremen and EU projects IMECC and GEOmon as well as maintenance and logistical work provided by AeroMeteo Service (Bia\u0142ystok) and the RAMCES team at LSCE (Gif-sur-Yvette, France). The PEARL Bruker 125HR measurements at Eureka were made by the Canadian Network for the Detection of Atmospheric Change (CANDAC), led by James R. Drummond, and in part by the Canadian Arctic ACE Validation Campaigns, led by Kaley A. Walker. They were supported by the Atlantic Innovation Fund/Nova Scotia Research Innovation Trust, Canada Foundation for Innovation, Canadian Foundation for Climate and Atmospheric Sciences, Canadian Space Agency, Environment Canada, Government of Canada International Polar Year funding, Natural Sciences and Engineering Research Council, Northern Scientific Training Program, Ontario Innovation Trust, Polar Continental Shelf Program, and Ontario Research Fund. The authors wish to thank Rebecca Batchelor and Ashley Harrett for the near-infrared upgrade of the instrument, PEARL site manager Pierre Fogal, the staff at the Eureka weather station, and the CANDAC operators for the logistical and on-site support provided at Eureka. Part of this work was performed at the Jet Propulsion Laboratory, California Institute of Technology, under contract with NASA. NCEP Reanalysis data is provided by the NOAA/OAR/ESRL PSD, Boulder, Colorado, USA, from their Web site at http://www.cdc.noaa.gov/.\n\nPublished - acp-11-12317-2011.pdf
", "abstract": "We describe a method of evaluating systematic errors in measurements of total column dry-air mole fractions of CO_2 (X_(CO_2)) from space, and we illustrate the method by applying it to the v2.8 Atmospheric CO_2 Observations from Space retrievals of the Greenhouse Gases Observing Satellite (ACOS-GOSAT) measurements over land. The approach exploits the lack of large gradients in X_(CO_2) south of 25\u00b0 S to identify large-scale offsets and other biases in the ACOS-GOSAT data with several retrieval parameters and errors in instrument calibration. We demonstrate the effectiveness of the method by comparing the ACOS-GOSAT data in the Northern Hemisphere with ground truth provided by the Total Carbon Column Observing Network (TCCON). We use the observed correlation between free-tropospheric potential temperature and X_(CO_2) in the Northern Hemisphere to define a dynamically informed coincidence criterion between the ground-based TCCON measurements and the ACOS-GOSAT measurements. We illustrate that this approach provides larger sample sizes, hence giving a more robust comparison than one that simply uses time, latitude and longitude criteria. Our results show that the agreement with the TCCON data improves after accounting for the systematic errors, but that extrapolation to conditions found outside the region south of 25\u00b0 S may be problematic (e.g., high airmasses, large surface pressure biases, M-gain, measurements made over ocean). A preliminary evaluation of the improved v2.9 ACOS-GOSAT data is also discussed.", "date": "2011-12-09", "date_type": "published", "publication": "Atmospheric Chemistry and Physics", "volume": "11", "number": "23", "publisher": "European Geosciences Union", "pagerange": "12317-12337", "id_number": "CaltechAUTHORS:20150220-094100128", "issn": "1680-7316", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150220-094100128", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NNX11AG01G" }, { "agency": "Department of Energy (DOE)" }, { "agency": "Australian Research Council", "grant_number": "LE0668470" }, { "agency": "Australian Research Council", "grant_number": "DP0879468" }, { "agency": "Australian Research Council", "grant_number": "DP110103118" }, { "agency": "Australian Research Council", "grant_number": "LP0562346" }, { "agency": "New Zealand Foundation of Research Science and Technology", "grant_number": "C01X0204" }, { "agency": "New Zealand Foundation for Research Science and Technology", "grant_number": "CO1X0406" }, { "agency": "Senate of Bremen" }, { "agency": "Atlantic Innovation Fund" }, { "agency": "European Union (EU)" }, { "agency": "Canada Foundation for Innovation" }, { "agency": "Canadian Foundation for Climate and Atmospheric Sciences" }, { "agency": "Canadian Space Agency (CSA)" }, { "agency": "Environment Canada" }, { "agency": "Government of Canada International Polar Year" }, { "agency": "Natural Sciences and Engineering Research Council of Canada (NSERC)" }, { "agency": "Northern Scientific Training Program" }, { "agency": "Ontario Innovation Trust" }, { "agency": "Polar Continental Shelf Program" }, { "agency": "Ontario Research Fund" }, { "agency": "Nova Scotia Research Innovation Trust" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/acp-11-12317-2011", "primary_object": { "basename": "acp-11-12317-2011.pdf", "url": "https://authors.library.caltech.edu/records/nekf7-8fa62/files/acp-11-12317-2011.pdf" }, "resource_type": "article", "pub_year": "2011", "author_list": "Wunch, D.; Wennberg, P. O.; et el." }, { "id": "https://authors.library.caltech.edu/records/zbax8-7xh10", "eprint_id": 28634, "eprint_status": "archive", "datestamp": "2023-08-22 04:13:27", "lastmod": "2023-10-24 18:02:09", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "D'Allura-A", "name": { "family": "D'Allura", "given": "Alessio" } }, { "id": "Kulkarni-Sarika", "name": { "family": "Kulkarni", "given": "Sarika" } }, { "id": "Carmichael-G-R", "name": { "family": "Carmichael", "given": "Gregory R." } }, { "id": "Finardi-S", "name": { "family": "Finardi", "given": "Sandro" } }, { "id": "Adhikari-B", "name": { "family": "Adhikari", "given": "Bhupesh" } }, { "id": "Wei-Chao", "name": { "family": "Wei", "given": "Chao" } }, { "id": "Streets-D-G", "name": { "family": "Streets", "given": "David" } }, { "id": "Zhang-Qiang", "name": { "family": "Zhang", "given": "Qiang" }, "orcid": "0000-0002-8376-131X" }, { "id": "Pierce-R-B", "name": { "family": "Pierce", "given": "Robert B." } }, { "id": "Al-Saadi-J-A", "name": { "family": "Al-Saadi", "given": "Jassim A." } }, { "id": "Diskin-G", "name": { "family": "Diskin", "given": "Glenn" } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul" }, "orcid": "0000-0002-6126-3854" } ] }, "title": "Meteorological and air quality forecasting using the WRF-STEM model during the 2008 ARCTAS field campaign", "ispublished": "pub", "full_text_status": "restricted", "keywords": "ARCTAS; Arctic; Air quality forecasting; Chemical weather", "note": "\u00a9 2011 Elsevier Ltd. \n\nReceived 11 August 2010; revised 12 February 2011; Accepted 14 February 2011. Available online 12 March 2011. \n\nWe would like to thank the ARCTAS Measurement Team for permission in using the measurements, CGRER and the University of Iowa. This work was supported in part by NASA grant NNX08AH56G. We would like to acknowledge Space Science and Engineering Center, University of Wisconsin-Madison, WI, USA for providing the cloud cover satellite composite images centered over the Arctic region.", "abstract": "In this study, the University of Iowa's Chemical Weather Forecasting System comprising meteorological predictions using the WRF model, and off-line chemical weather predictions using tracer and full chemistry versions of the STEM model, designed to support the flight planning during the ARCTAS 2008 mission is described and evaluated. The system includes tracers representing biomass burning and anthropogenic emissions from different geographical emissions source regions, as well as air mass age indicators. We demonstrate how this forecasting system was used in flight planning and in the interpretation of the experimental data obtained through the case study of the summer mission ARCTAS DC-8 flight executed on July 9 2008 that sampled near the North Pole. The comparison of predicted meteorological variables including temperature, pressure, wind speed and wind direction against the flight observations shows that the WRF model is able to correctly describe the synoptic circulation and cloud coverage in the Arctic region The absolute values of predicted CO match the measured CO closely suggesting that the STEM model is able to capture the variability in observations within the Arctic region. The time\u2013altitude cross sections of source region tagged CO tracers along the flight track helped in identifying biomass burning (from North Asia) and anthropogenic (largely China) as major sources contributing to the observed CO along this flight. The difference between forecast and post analysis biomass burning emissions can lead to significant changes (\u223c10\u201350%) in primary CO predictions reflecting the large uncertainty associated with biomass burning estimates and the need to reduce this uncertainty for effective flight planning.", "date": "2011-12", "date_type": "published", "publication": "Atmospheric Environment", "volume": "45", "number": "38", "publisher": "Elsevier", "pagerange": "6901-6910", "id_number": "CaltechAUTHORS:20120103-153610191", "issn": "1352-2310", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20120103-153610191", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NNX08AH56G" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/j.atmosenv.2011.02.073", "resource_type": "article", "pub_year": "2011", "author_list": "D'Allura, Alessio; Kulkarni, Sarika; et el." }, { "id": "https://authors.library.caltech.edu/records/yhv9p-aa535", "eprint_id": 103571, "eprint_status": "archive", "datestamp": "2023-08-22 04:07:14", "lastmod": "2023-10-20 16:30:17", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Messerschmidt-J", "name": { "family": "Messerschmidt", "given": "J." } }, { "id": "Geibel-M-C", "name": { "family": "Geibel", "given": "M. C." } }, { "id": "Blumenstock-T", "name": { "family": "Blumenstock", "given": "T." } }, { "id": "Chen-H", "name": { "family": "Chen", "given": "H." } }, { "id": "Deutscher-N-M", "name": { "family": "Deutscher", "given": "N. M." }, "orcid": "0000-0002-2906-2577" }, { "id": "Engel-A-E-J", "name": { "family": "Engel", "given": "A." } }, { "id": "Feist-D-G", "name": { "family": "Feist", "given": "D. G." }, "orcid": "0000-0002-5890-6687" }, { "id": "Gerbig-C", "name": { "family": "Gerbig", "given": "C." }, "orcid": "0000-0002-1112-8603" }, { "id": "Gisi-M", "name": { "family": "Gisi", "given": "M." } }, { "id": "Hase-F", "name": { "family": "Hase", "given": "F." } }, { "id": "Katrynski-K", "name": { "family": "Katrynski", "given": "K." } }, { "id": "Kolle-O", "name": { "family": "Kolle", "given": "O." } }, { "id": "Lavri\u010d-J-V", "name": { "family": "Lavri\u010d", "given": "J. V." } }, { "id": "Notholt-J", "name": { "family": "Notholt", "given": "J." } }, { "id": "Palm-M", "name": { "family": "Palm", "given": "M." } }, { "id": "Ramonet-M", "name": { "family": "Ramonet", "given": "M." } }, { "id": "Rettinger-M", "name": { "family": "Rettinger", "given": "M." } }, { "id": "Schmidt-M-E", "name": { "family": "Schmidt", "given": "M." } }, { "id": "Sussmann-R", "name": { "family": "Sussmann", "given": "R." } }, { "id": "Toon-G-C", "name": { "family": "Toon", "given": "G. C." }, "orcid": "0000-0003-4174-7541" }, { "id": "Truong-Frank", "name": { "family": "Truong", "given": "F." } }, { "id": "Warneke-T", "name": { "family": "Warneke", "given": "T." }, "orcid": "0000-0001-5185-3415" }, { "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": "Xueref-Remy-I", "name": { "family": "Xueref-Remy", "given": "I." } } ] }, "title": "Calibration of TCCON column-averaged CO\u2082: the first aircraft campaign over European TCCON sites", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 Author(s) 2011. This work is distributed under the Creative Commons Attribution 3.0 License. \n\nReceived: 14 Mar 2011 \u2013 Discussion started: 12 May 2011 \u2013 Revised: 30 Sep 2011 \u2013 Accepted: 13 Oct 2011 \u2013 Published: 02 Nov 2011. \n\nSpecial issue: An integrated approach to study atmospheric greenhouse and related gases at the Bialystok tall tower, eastern Poland (ACP/AMT inter-journal SI)(ACP/AMT inter-journal SI) Editor(s): M. Heimann, J. Brandt, J. V. Lavri\u010d, and D. Brunner. Special issue jointly organized between Atmospheric Chemistry and Physics and Atmospheric Measurement Techniques.\n\nWe acknowledge the support of the European Commission within the 6th Framework Program through the Integrated Infrastructure Initiative IMECC (Infrastructure for Measurement of the European Carbon Cycle) and the Integrated Project GEOmon (Global Earth Observation and Monitoring). \n\nThe aircraft measurements would not have been possible without the great support from Enviscope GmbH (Frankfurt am Main, Germany), especially Rolf Maser and Christoph Klaus, who were responsible for the aircraft instrument integration and operation. We would also like to thank the Gesellschaft f\u00fcr Flugzieldarstellung mbH (Hohn, Germany), especially Svend Engemann and the other pilots, for their excellent support with flight planning and flight operations. We thank the Polish Air Navigation Services Agency for the organization of the overpass in Bialystok, Poland. \n\nAt the Institute of Environmental Physics (Bremen, Germany) Katinka Petersen, Christof Petri, Benjamin Sampson and Christine Weinzierl have contributed greatly to the success of the campaign. From the Max Planck Institute for Biogeochemistry (Jena, Germany) we would like to thank Stephan Baum, Armin Jordan, Martin Hertel, Karl K\u00fcbler, and Bert Steinberg for their contributions. We thank the members of RAMCES team at LSCE (Gif-sur-Yvette, France) for maintaining the Orl\u00e9ans FTS site and providing station logistics. We would also like to thank Peter Rayner at the University of Melbourne, Australia for the coordination of the project IMECC and helpful comments on the article. \n\nImplementation of TCCON data processing is supported by a grant from NASA's Carbon Cycle Program (NNX08AI86G) to the California Institute of Technology. Part of this work was performed at the Jet Propulsion Laboratory, California Institute of Technology, under contract with NASA. \n\nEdited by: J. Brandt.\n\nPublished - acp-11-10765-2011.pdf
Supplemental Material - acp-11-10765-2011-supplement-1.pdf
", "abstract": "The Total Carbon Column Observing Network (TCCON) is a ground-based network of Fourier Transform Spectrometer (FTS) sites around the globe, where the column abundances of CO\u2082, CH\u2084, N\u2082O, CO and O\u2082 are measured. CO\u2082 is constrained with a precision better than 0.25% (1-\u03c3). To achieve a similarly high accuracy, calibration to World Meteorological Organization (WMO) standards is required. This paper introduces the first aircraft calibration campaign of five European TCCON sites and a mobile FTS instrument. A series of WMO standards in-situ profiles were obtained over European TCCON sites via aircraft and compared with retrievals of CO\u2082 column amounts from the TCCON instruments. The results of the campaign show that the FTS measurements are consistently biased 1.1% \u00b1 0.2% low with respect to WMO standards, in agreement with previous TCCON calibration campaigns. The standard a priori profile for the TCCON FTS retrievals is shown to not add a bias. The same calibration factor is generated using aircraft profiles as a priori and with the TCCON standard a priori. With a calibration to WMO standards, the highly precise TCCON CO\u2082 measurements of total column concentrations provide a suitable database for the calibration and validation of nadir-viewing satellites.", "date": "2011-11-02", "date_type": "published", "publication": "Atmospheric Chemistry and Physics", "volume": "11", "number": "21", "publisher": "European Geosciences Union", "pagerange": "10765-10777", "id_number": "CaltechAUTHORS:20200529-093435286", "issn": "1680-7324", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200529-093435286", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "European Commission" }, { "agency": "NASA", "grant_number": "NNX08AI86G" }, { "agency": "NASA/JPL/Caltech" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/acp-11-10765-2011", "primary_object": { "basename": "acp-11-10765-2011.pdf", "url": "https://authors.library.caltech.edu/records/yhv9p-aa535/files/acp-11-10765-2011.pdf" }, "related_objects": [ { "basename": "acp-11-10765-2011-supplement-1.pdf", "url": "https://authors.library.caltech.edu/records/yhv9p-aa535/files/acp-11-10765-2011-supplement-1.pdf" } ], "resource_type": "article", "pub_year": "2011", "author_list": "Messerschmidt, J.; Geibel, M. C.; et el." }, { "id": "https://authors.library.caltech.edu/records/cp3hh-fnv45", "eprint_id": 25281, "eprint_status": "archive", "datestamp": "2023-08-22 03:26:56", "lastmod": "2023-10-24 15:45:34", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Barkley-M-P", "name": { "family": "Barkley", "given": "Michael P." } }, { "id": "Palmer-P-I", "name": { "family": "Palmer", "given": "Paul I." } }, { "id": "Ganzeveld-L", "name": { "family": "Ganzeveld", "given": "Laurens" } }, { "id": "Arneth-A", "name": { "family": "Arneth", "given": "Almut" } }, { "id": "Hagberg-D", "name": { "family": "Hagberg", "given": "Daniel" } }, { "id": "Karl-T", "name": { "family": "Karl", "given": "Thomas" } }, { "id": "Guenther-A", "name": { "family": "Guenther", "given": "Alex" } }, { "id": "Paulot-F", "name": { "family": "Paulot", "given": "Fabien" }, "orcid": "0000-0001-7534-4922" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Mao-Jingqiu", "name": { "family": "Mao", "given": "Jingqiu" } }, { "id": "Kurosu-T-P", "name": { "family": "Kurosu", "given": "Thomas P." } }, { "id": "Chance-K", "name": { "family": "Chance", "given": "Kelly" } }, { "id": "M\u00fcller-J-F", "name": { "family": "M\u00fcller", "given": "J.-F" } }, { "id": "De-Smedt-I", "name": { "family": "De Smedt", "given": "Isabelle" } }, { "id": "Van-Roozendael-M", "name": { "family": "Van Roozendael", "given": "Michel" } }, { "id": "Chen-Dan", "name": { "family": "Chen", "given": "Dan" } }, { "id": "Wang-Yuxuan", "name": { "family": "Wang", "given": "Yuxuan" } }, { "id": "Yantosca-R-M", "name": { "family": "Yantosca", "given": "Robert M." } } ] }, "title": "Can a \"state of the art\" chemistry transport model simulate Amazonian tropospheric chemistry?", "ispublished": "pub", "full_text_status": "public", "keywords": "Amazon; GEOS-Chem; OMI; SCIAMACHY; formaldehyde; isoprene", "note": "\u00a9 2011 by the American Geophysical Union. \nReceived 2 March 2011; revised 8 April 2011; accepted 10 May 2011; published 17 August 2011.\nThe authors would like to thank all members of the GABRIEL Science team for their provision of the aircraft data. We would also like to thank Lee Murray (Harvard University) for his help with\nthe local lightning distribution and Daniel Stone and Mat Evans (University of Leeds) for their help setting up the box model. The GEOS\u2010Chem model is managed at Harvard University with support from the NASA Atmospheric Chemistry Modeling and Analysis Program. This work was supported\nby the Natural Environment Research Council (NERC research grants NE/G013810/1 and NE/D001471). A.A. and D.H. acknowledge support from the Swedish Research Council Formas.\n\nPublished - Barkley2011p15712J_Geophys_Res-Atmos.pdf
", "abstract": "We present an evaluation of a nested high-resolution Goddard Earth Observing System (GEOS)-Chem chemistry transport model simulation of tropospheric chemistry over tropical South America. The model has been constrained with two isoprene emission inventories: (1) the canopy-scale Model of Emissions of Gases and Aerosols from Nature (MEGAN) and (2) a leaf-scale algorithm coupled to the Lund-Potsdam-Jena General Ecosystem Simulator (LPJ-GUESS) dynamic vegetation model, and the model has been run using two different chemical mechanisms that contain alternative treatments of isoprene photo-oxidation. Large differences of up to 100 Tg C yr^(\u22121) exist between the isoprene emissions predicted by each inventory, with MEGAN emissions generally higher. Based on our simulations we estimate that tropical South America (30\u201385\u00b0W, 14\u00b0N\u201325\u00b0S) contributes about 15\u201335% of total global isoprene emissions. We have quantified the model sensitivity to changes in isoprene emissions, chemistry, boundary layer mixing, and soil NO_x emissions using ground-based and airborne observations. We find GEOS-Chem has difficulty reproducing several observed chemical species; typically hydroxyl concentrations are underestimated, whilst mixing ratios of isoprene and its oxidation products are overestimated. The magnitude of model formaldehyde (HCHO) columns are most sensitive to the choice of chemical mechanism and isoprene emission inventory. We find GEOS-Chem exhibits a significant positive bias (10\u2013100%) when compared with HCHO columns from the Scanning Imaging Absorption Spectrometer for Atmospheric Chartography (SCIAMACHY) and Ozone Monitoring Instrument (OMI) for the study year 2006. Simulations that use the more detailed chemical mechanism and/or lowest isoprene emissions provide the best agreement to the satellite data, since they result in lower-HCHO columns.", "date": "2011-08-17", "date_type": "published", "publication": "Journal of Geophysical Research D", "volume": "116", "publisher": "American Geophysical Union", "pagerange": "Art. No. D16302", "id_number": "CaltechAUTHORS:20110909-153101927", "issn": "0148-0227", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20110909-153101927", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA" }, { "agency": "Natural Environment Research Council (NERC)", "grant_number": "NE/G013810/1" }, { "agency": "Natural Environment Research Council (NERC)", "grant_number": "NE/D001471" }, { "agency": "Swedish Research Council Formas" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2011JD015893", "primary_object": { "basename": "Barkley2011p15712J_Geophys_Res-Atmos.pdf", "url": "https://authors.library.caltech.edu/records/cp3hh-fnv45/files/Barkley2011p15712J_Geophys_Res-Atmos.pdf" }, "resource_type": "article", "pub_year": "2011", "author_list": "Barkley, Michael P.; Palmer, Paul I.; et el." }, { "id": "https://authors.library.caltech.edu/records/bp2sj-xar71", "eprint_id": 24329, "eprint_status": "archive", "datestamp": "2023-08-22 03:26:14", "lastmod": "2023-10-23 20:36:09", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Crounse-J-D", "name": { "family": "Crounse", "given": "John D." }, "orcid": "0000-0001-5443-729X" }, { "id": "Paulot-F", "name": { "family": "Paulot", "given": "Fabien" }, "orcid": "0000-0001-7534-4922" }, { "id": "Kjaergaard-H-G", "name": { "family": "Kjaergaard", "given": "Henrik G." }, "orcid": "0000-0002-7275-8297" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "Peroxy radical isomerization in the oxidation of isoprene", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2011 the Owner Societies.\n\nReceived 26 Apr 2011, Accepted 08 Jun 2011; First published on the web 24 Jun 2011.\n\nWe thank N. C. Eddingsaas for the design and construction of\nthe mini-chamber used in this work, M. R. Beaver for assistance with experiments, J. M. St. Clair for instrumental assistance, K. M. Spencer for providing CIMS calibrations of glycolaldehyde and hydroxyacetone, and D. L. Thomsen and H. C. Knap for assistance with theoretical calulations. We thank NASA (NNX08AD29G) and NSF (ATM-0934408) for funding in support of this work. We thank the Danish Council for Independent Research-Natural Sciences and the Danish Center for Scientific Computing (DCSC) for funding. FP acknowledges support from NASA earth and space science fellowship.\n\nPublished - Crounse2011p14390Physical_chemistry_chemical_physics_PCCP.pdf
Supplemental Material - c1cp21330j.pdf
", "abstract": "We report experimental evidence for the formation of C5-hydroperoxyaldehydes (HPALDs) from 1,6-H-shift isomerizations in peroxy radicals formed from the hydroxyl radical (OH) oxidation of 2-methyl-1,3-butadiene (isoprene). At 295 K, the isomerization rate of isoprene peroxy radicals (ISO\u2219_2) relative to the rate of reaction of (ISO\u2219_2) + HO_2 is (k^(295)_(isom))/(k^(295)_((ISO\u2219_2) + HO_2) = (1.2\u00b10.6) \u00d7 10^8 mol cm^(-2), or k^(295)_(isom)\u22430.002 s^(-1). The temperature dependence of this rate was determined through experiments conducted at 295, 310 and 318 K and is well described by (k_(isom))T))/(k_((ISO\u2219_2)+HO_2) (T) = 2.0 \u00d7 10^(21) exp(-9000/T)mol cm^(-3). The overall uncertainty in the isomerization rate (relative to k_((ISO\u2219_2)+HO_2) is\nestimated to be 50%. Peroxy radicals from the oxidation of the fully deuterated isoprene analog isomerize at a rate of ~15 times slower than non-deuterated isoprene. The fraction of isoprene peroxy radicals reacting by 1,6-H-shift isomerization is estimated to be 8\u201311% globally, with values up to 20% in tropical regions.", "date": "2011-08-14", "date_type": "published", "publication": "Physical Chemistry Chemical Physics", "volume": "13", "number": "30", "publisher": "Royal Society of Chemistry", "pagerange": "13607-13613", "id_number": "CaltechAUTHORS:20110707-082741650", "issn": "1463-9076", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20110707-082741650", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NNX08AD29G" }, { "agency": "NSF", "grant_number": "ATM-0934408" }, { "agency": "Danish Council for Independent Research-Natural Sciences" }, { "agency": "Danish Center for Scientific Computing (DCSC)" }, { "agency": "NASA Earth and Space Science Fellowship" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1039/c1cp21330j", "primary_object": { "basename": "Crounse2011p14390Physical_chemistry_chemical_physics_PCCP.pdf", "url": "https://authors.library.caltech.edu/records/bp2sj-xar71/files/Crounse2011p14390Physical_chemistry_chemical_physics_PCCP.pdf" }, "related_objects": [ { "basename": "c1cp21330j.pdf", "url": "https://authors.library.caltech.edu/records/bp2sj-xar71/files/c1cp21330j.pdf" } ], "resource_type": "article", "pub_year": "2011", "author_list": "Crounse, John D.; Paulot, Fabien; et el." }, { "id": "https://authors.library.caltech.edu/records/0mtej-sj588", "eprint_id": 25211, "eprint_status": "archive", "datestamp": "2023-08-22 03:25:10", "lastmod": "2023-10-24 15:42:29", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Parker-R", "name": { "family": "Parker", "given": "Robert" } }, { "id": "Boesch-H", "name": { "family": "Boesch", "given": "Hartmut" }, "orcid": "0000-0003-3944-9879" }, { "id": "Cogan-A", "name": { "family": "Cogan", "given": "Austin" } }, { "id": "Fraser-A", "name": { "family": "Fraser", "given": "Annemarie" } }, { "id": "Feng-Liang", "name": { "family": "Feng", "given": "Liang" } }, { "id": "Palmer-P-I", "name": { "family": "Palmer", "given": "Paul I." } }, { "id": "Messerschmidt-J", "name": { "family": "Messerschmidt", "given": "Janina" } }, { "id": "Deutscher-N", "name": { "family": "Deutscher", "given": "Nicholas" } }, { "id": "Griffith-D-W-T", "name": { "family": "Griffith", "given": "David W. T." }, "orcid": "0000-0002-7986-1924" }, { "id": "Notholt-J", "name": { "family": "Notholt", "given": "Justus" } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Wunch-D", "name": { "family": "Wunch", "given": "Debra" }, "orcid": "0000-0002-4924-0377" } ] }, "title": "Methane observations from the Greenhouse Gases Observing\n SATellite: Comparison to ground\u2010based TCCON data and model calculations", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2011 American Geophysical Union. Received 20 April 2011; accepted 27 June 2011; published 6 August 2011. We thank JAXA, NIES, and MOE for the GOSAT data and their continuous support as part of the Joint Research Agreement. R.P., L.F., and A.F. are supported by the NCEO and H.B. is\nsupported by a RCUK fellowship. We also thank the OCO team at JPL for supplying the retrieval algorithm. We thank the BADC for providing ECMWF Operational Analyses data. TCCON is supported by NASA's Terrestrial Ecology Program through a grant to the California Institute of Technology. Operations support for Lamont and Darwin is provided\nby NASA's OCO. For the TCCON sites at Bialystok and Orleans, we thank AeroMeteo Service and the RAMCES team at LSCE for station maintenance and acknowledge the funding by the GOSAT team and within the EU\u2010projects IMECC and GEOmon. We would also like to thank Geoff Toon for his advice and comments. The Editor thanks two anonymous reviewers for their assistance in evaluating this paper.\n\nPublished - Parker2011p15600Geophys_Res_Lett.pdf
", "abstract": "We report new short-wave infrared (SWIR) column retrievals of atmospheric methane (X_(CH4)) from the Japanese Greenhouse Gases Observing SATellite (GOSAT) and compare observed spatial and temporal variations with correlative ground-based measurements from the Total Carbon Column Observing Network (TCCON) and with the global 3-D GEOS-Chem chemistry transport model. GOSAT X_(CH4) retrievals are compared with daily TCCON observations at six sites between April 2009 and July 2010 (Bialystok, Park Falls, Lamont, Orleans, Darwin and Wollongong). GOSAT reproduces the site-dependent seasonal cycles as observed by TCCON with correlations typically between 0.5 and 0.7 with an estimated single-sounding precision between 0.4\u20130.8%. We find a latitudinal-dependent difference between the X_(CH4) retrievals from GOSAT and TCCON which ranges from 17.9 ppb at the most northerly site (Bialystok) to \u221214.6 ppb at the site with the lowest latitude (Darwin). We estimate that the mean smoothing error difference included in the GOSAT to TCCON comparisons can account for 15.7 to 17.4 ppb for the northerly sites and for 1.1 ppb at the lowest latitude site. The GOSAT X_(CH4) retrievals agree well with the GEOS-Chem model on annual (August 2009 \u2013 July 2010) and monthly timescales, capturing over 80% of the zonal variability. Differences between model and observed X_(CH4) are found over key source regions such as Southeast Asia and central Africa which will be further investigated using a formal inverse model analysis.", "date": "2011-08-06", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "38", "publisher": "American Geophysical Union", "pagerange": "Art. No. L15807", "id_number": "CaltechAUTHORS:20110902-112604849", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20110902-112604849", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NCEO" }, { "agency": "Research Councils UK (RCUK)" }, { "agency": "NASA" }, { "agency": "GOSAT" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2011GL047871", "primary_object": { "basename": "Parker2011p15600Geophys_Res_Lett.pdf", "url": "https://authors.library.caltech.edu/records/0mtej-sj588/files/Parker2011p15600Geophys_Res_Lett.pdf" }, "resource_type": "article", "pub_year": "2011", "author_list": "Parker, Robert; Boesch, Hartmut; et el." }, { "id": "https://authors.library.caltech.edu/records/c1jsx-50k73", "eprint_id": 24673, "eprint_status": "archive", "datestamp": "2023-08-22 03:12:38", "lastmod": "2023-10-23 23:34:42", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Vay-S-A", "name": { "family": "Vay", "given": "S. A." } }, { "id": "Choi-Y", "name": { "family": "Choi", "given": "Y." } }, { "id": "Vadrevu-K-P", "name": { "family": "Vadrevu", "given": "K. P." } }, { "id": "Blake-D-R", "name": { "family": "Blake", "given": "D. R." } }, { "id": "Tyler-S-C", "name": { "family": "Tyler", "given": "S. C." } }, { "id": "Wisthaler-A", "name": { "family": "Wisthaler", "given": "A." } }, { "id": "Hecobian-A", "name": { "family": "Hecobian", "given": "A." } }, { "id": "Kondo-K", "name": { "family": "Kondo", "given": "K." } }, { "id": "Diskin-G-S", "name": { "family": "Diskin", "given": "G. S." }, "orcid": "0000-0002-3617-0269" }, { "id": "Sachse-G-W", "name": { "family": "Sachse", "given": "G. W." } }, { "id": "Woo-J-H", "name": { "family": "Woo", "given": "J.-H." } }, { "id": "Weinheimer-A-J", "name": { "family": "Weinheimer", "given": "A. J." }, "orcid": "0000-0001-6175-8286" }, { "id": "Burkhart-J-F", "name": { "family": "Burkhart", "given": "J. F." } }, { "id": "Stohl-A", "name": { "family": "Stohl", "given": "A." } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "Patterns of CO_2 and radiocarbon across high northern latitudes during International Polar Year 2008", "ispublished": "pub", "full_text_status": "public", "keywords": "^(14)CO_2, ARCTAS, CO_2, International Polar Year, POLARCAT, airborne observations", "note": "\u00a9 2011 American Geophysical Union. Received 15 January 2011; revised 27 March 2011; accepted 25 April 2011; published 16 July 2011. The authors wish to thank Xiaomei Xu, Scott Lehman, and Ingeborg Levin for use of the Point Barrow, Niwot Ridge, and Jungfraujoch \u0394^(14)CO_2 data, respectively. We also appreciate the CO_2 data provided by Doug Worthy of Environment Canada and NOAA ESRL, as well as contributions from Melissa Yang. We are most grateful to Jimmy Geiger, Jim Plant, and the DC-8 crew whose valuable\ncontributions ensured a successful and safe mission. This research was funded by NASA's Global Tropospheric Chemistry and Radiation Sciences Programs. CH_3CN measurements were supported by the Austrian Research Promotion Agency (FFG-ALR) and the Tiroler Zukunftstiftung, and carried\nout with the help/support of T. Mikoviny, M. Graus, A. Hansel, and T. D. Maerk.\n\nPublished - Vay2011p15363J_Geophys_Res-Atmos.pdf
", "abstract": "High-resolution in situ CO_2 measurements were conducted aboard the NASA DC-8 aircraft during the ARCTAS/POLARCAT field campaign, a component of the wider 2007\u20132008 International Polar Year activities. Data were recorded during large-scale surveys spanning the North American sub\u2010Arctic to the North Pole from 0.04 to 12 km altitude\nin spring and summer of 2008. Influences on the observed CO_2 concentrations were investigated using coincident CO, black carbon, CH_3CN, HCN, O_3, C_2Cl_4, and \u0394^(14)CO_2 data, and the FLEXPART model. In spring, the CO_2 spatial distribution from 55\u00b0N to 90\u00b0N was largely determined by the long-range transport of air masses laden with Asian\nanthropogenic pollution intermingled with Eurasian fire emissions evidenced by the greater variability in the mid-to-upper troposphere. At the receptor site, the enhancement ratios of CO_2 to CO in pollution plumes ranged from 27 to 80 ppmv ppmv^(\u22121) with the highest anthropogenic content registered in plumes sampled poleward of 80\u00b0N. In summer, the CO_2 signal largely reflected emissions from lightning-ignited wildfires within the boreal forests of\nnorthern Saskatchewan juxtaposed with uptake by the terrestrial biosphere. Measurements within fresh fire plumes yielded CO_2 to CO emission ratios of 4 to 16 ppmv ppmv^(\u22121) and a mean CO_2 emission factor of 1698 \u00b1 280 g kg^(\u22121) dry matter. From the ^(14)C in CO_2 content of 48 whole air samples, mean spring (46.6 \u00b1 4.4\u2030) and summer (51.5 \u00b1 5\u2030) \u0394^(14)CO_2 values indicate a 5\u2030 seasonal difference. Although the northern midlatitudes were identified as the emissions source regions for the majority of the spring samples, depleted \u0394^(14)CO_2 values were observed in <1% of the data set. Rather, ARCTAS \u0394^(14)CO_2 observations (54%) revealed predominately a pattern of positive disequilibrium (1\u20137\u2030) with respect to background regardless of season owing to both heterotrophic respiration and fire-induced combustion of biomass. Anomalously enriched \u0394^(14)CO_2 values (101\u2013262\u2030) measured\nin emissions from Lake Athabasca and Eurasian fires speak to biomass burning as an increasingly important contributor to the mass excess in \u0394^(14)CO_2 observations in a warming\nArctic, representing an additional source of uncertainty in the quantification of fossil fuel CO_2.", "date": "2011-07-16", "date_type": "published", "publication": "Journal of Geophysical Research D", "volume": "116", "publisher": "American Geophysical Union", "pagerange": "Art. No. D14301", "id_number": "CaltechAUTHORS:20110804-090820448", "issn": "0148-0227", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20110804-090820448", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA" }, { "agency": "Austrian Research Promotion Agency (FFG-ALR)" }, { "agency": "Tiroler Zukunftstiftung" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2011JD015643", "primary_object": { "basename": "Vay2011p15363J_Geophys_Res-Atmos.pdf", "url": "https://authors.library.caltech.edu/records/c1jsx-50k73/files/Vay2011p15363J_Geophys_Res-Atmos.pdf" }, "resource_type": "article", "pub_year": "2011", "author_list": "Vay, S. A.; Choi, Y.; et el." }, { "id": "https://authors.library.caltech.edu/records/gfddq-x5481", "eprint_id": 25012, "eprint_status": "archive", "datestamp": "2023-08-22 03:12:32", "lastmod": "2023-10-24 15:32:38", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Butz-A", "name": { "family": "Butz", "given": "A." }, "orcid": "0000-0003-0593-1608" }, { "id": "Guerlet-S", "name": { "family": "Guerlet", "given": "S." } }, { "id": "Hasekamp-O", "name": { "family": "Hasekamp", "given": "O." } }, { "id": "Schepers-D", "name": { "family": "Schepers", "given": "D." } }, { "id": "Galli-A", "name": { "family": "Galli", "given": "A." } }, { "id": "Aben-I", "name": { "family": "Aben", "given": "I." } }, { "id": "Frankenberg-C", "name": { "family": "Frankenberg", "given": "C." }, "orcid": "0000-0002-0546-5857" }, { "id": "Hartmann-J-M", "name": { "family": "Hartmann", "given": "J.-M." } }, { "id": "Tran-H", "name": { "family": "Tran", "given": "H." } }, { "id": "Kuze-A", "name": { "family": "Kuze", "given": "A." } }, { "id": "Keppel-Aleks-G", "name": { "family": "Keppel-Aleks", "given": "G." } }, { "id": "Toon-G", "name": { "family": "Toon", "given": "G." } }, { "id": "Wunch-D", "name": { "family": "Wunch", "given": "D." }, "orcid": "0000-0002-4924-0377" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Deutscher-N", "name": { "family": "Deutscher", "given": "N." } }, { "id": "Griffith-D", "name": { "family": "Griffith", "given": "D." } }, { "id": "Messerschmidt-J", "name": { "family": "Messerschmidt", "given": "J." } }, { "id": "Macatangay-R", "name": { "family": "Macatangay", "given": "R." } }, { "id": "Notholt-J", "name": { "family": "Notholt", "given": "J." } }, { "id": "Warneke-T", "name": { "family": "Warneke", "given": "T." }, "orcid": "0000-0001-5185-3415" } ] }, "title": "Toward accurate CO_2 and CH_4 observations from GOSAT", "ispublished": "pub", "full_text_status": "public", "keywords": "GOSAT; carbon dioxide; methane; satellite remote sensing", "note": "\u00a9 2011 American Geophysical Union.\n\nReceived 21 April 2011; revised 14 June 2011; accepted 20 June 2011; published 30 July 2011.\n\nAccess to GOSAT data was granted through\nthe 2nd GOSAT research announcement jointly issued by JAXA, NIES, and MOE. Funding of this research came from the Dutch User Support Program under project GO\u20102005/064 and GO\u2010AO/21 (DS), from ESA's CCI on GHGs and the European Commission's 7th framework program under grant agreement 218793 (SG), from DFG's Emmy\u2010Noether program under project RemoteC BU2599/1\u20101 (AB). ECMWF ERA Interim analyses are provided\nthrough http://data\u2010portal.ecmwf.int/data/d/interim_daily/. GTOPO30 is available from the U.S. Geological Survey through the Earth Resources Observation and Science (EROS) Center (http://eros.usgs.gov/#/Find_\nData/Products_and_Data_Available/gtopo30_info). CarbonTracker data are provided by NOAA ESRL, Boulder, Colorado, USA from the Web site at http://carbontracker.noaa.gov. TM4 fields have been made available through Jan\u2010Fokke Meirink, Royal Netherlands Meteorological Institute (KNMI). US funding for TCCON comes from NASA's Terrestrial Ecology Program (NNX08A186G), the Orbiting Carbon Observatory Program (NAS7\u201003001), the DOE/ARM Program and the Atmospheric CO2 Observations from Space Program. Some of the research described in this paper was performed at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the NASA. We acknowledge the support of the European Commission within the 6th Framework Program through the Integrated\nInfrastructure Initiative IMECC and the Integrated Project GEOmon. We thank AeroMeteo Service, (Bialystok, Poland) and the RAMCES team at LSCE (Gif\u2010sur\u2010Yvette, France) for maintaining the Bialystok and Orleans FTS sites and providing station logistics. The Editor thanks two anonymous reviewers for their assistance in evaluating this paper.\n\nPublished - Butz2011p15550Geophys_Res_Lett.pdf
", "abstract": "The column-average dry air mole fractions of atmospheric carbon dioxide and methane (X_(CO_2) and X_(CH_4)) are inferred from observations of backscattered sunlight conducted by the Greenhouse gases Observing SATellite (GOSAT). Comparing the first year of GOSAT retrievals over land with colocated ground-based observations of the Total Carbon Column Observing Network (TCCON), we find an average difference (bias) of \u22120.05% and \u22120.30% for X_(CO_2) and X_(CH_4) with a station-to-station variability (standard deviation of the bias) of 0.37% and 0.26% among the 6 considered TCCON sites. The root-mean square deviation of the bias-corrected satellite retrievals from colocated TCCON observations amounts to 2.8 ppm for X_(CO_2) and 0.015 ppm for X_(CH_4). Without any data averaging, the GOSAT records reproduce general source/sink patterns such as the seasonal cycle of X_(CO_2) suggesting the use of the satellite retrievals for constraining surface fluxes.", "date": "2011-07-15", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "38", "number": "14", "publisher": "American Geophysical Union", "pagerange": "Art. No. L14812", "id_number": "CaltechAUTHORS:20110824-113431250", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20110824-113431250", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Netherlands Space Office", "grant_number": "GO\u20102005/064" }, { "agency": "Netherlands Space Office", "grant_number": "GO\u2010AO/21" }, { "agency": "European Research Council (ERC)", "grant_number": "218793" }, { "agency": "Deutsche Forschungsgemeinschaft (DFG)", "grant_number": "BU2599/1-1" }, { "agency": "NASA", "grant_number": "NNX08A186G" }, { "agency": "NASA", "grant_number": "NAS7-03001" }, { "agency": "Department of Energy (DOE)" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2011GL047888", "primary_object": { "basename": "Butz2011p15550Geophys_Res_Lett.pdf", "url": "https://authors.library.caltech.edu/records/gfddq-x5481/files/Butz2011p15550Geophys_Res_Lett.pdf" }, "resource_type": "article", "pub_year": "2011", "author_list": "Butz, A.; Guerlet, S.; et el." }, { "id": "https://authors.library.caltech.edu/records/yqqw2-3qw43", "eprint_id": 25304, "eprint_status": "archive", "datestamp": "2023-08-22 03:10:18", "lastmod": "2023-10-24 15:46:39", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Simpson-I-J", "name": { "family": "Simpson", "given": "I. J." } }, { "id": "Akagi-S-K", "name": { "family": "Akagi", "given": "S. K." } }, { "id": "Barletta-B", "name": { "family": "Barletta", "given": "B." } }, { "id": "Blake-N-J", "name": { "family": "Blake", "given": "N. J." } }, { "id": "Choi-Y", "name": { "family": "Choi", "given": "Y." } }, { "id": "Diskin-G-S", "name": { "family": "Diskin", "given": "G. S." }, "orcid": "0000-0002-3617-0269" }, { "id": "Fried-A", "name": { "family": "Fried", "given": "A." } }, { "id": "Fuelberg-H-E", "name": { "family": "Fuelberg", "given": "H. E." } }, { "id": "Meinardi-S", "name": { "family": "Meinardi", "given": "S." } }, { "id": "Rowland-F-S", "name": { "family": "Rowland", "given": "F. S." } }, { "id": "Vay-S-A", "name": { "family": "Vay", "given": "S. A." } }, { "id": "Weinheimer-A-J", "name": { "family": "Weinheimer", "given": "A. J." }, "orcid": "0000-0001-6175-8286" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Wiebring-P", "name": { "family": "Wiebring", "given": "P." } }, { "id": "Wisthaler-A", "name": { "family": "Wisthaler", "given": "A." } }, { "id": "Yang-M", "name": { "family": "Yang", "given": "M." } }, { "id": "Yokelson-R-J", "name": { "family": "Yokelson", "given": "R. J." }, "orcid": "0000-0002-8415-6808" }, { "id": "Blake-D-R", "name": { "family": "Blake", "given": "D. R." } } ] }, "title": "Boreal forest fire emissions in fresh Canadian smoke plumes: C_1-C_(10) volatile organic compounds (VOCs), CO_2, CO, NO_2, NO, HCN and CH_3CN", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 Author(s) 2011. This work is distributed under the Creative Commons Attribution 3.0 License. \n\nReceived: 2 March 2011. Published in Atmos. Chem. Phys. Discuss.: 22 March 2011. Revised: 17 June 2011. Accepted: 29 June 2011. Published: 7 July 2011. \n\nThe ARCTAS mission was funded by the NASA Global Tropospheric Chemistry Program, the NASA Radiation Sciences Program, and the California Air Resources Board. The VOC research presented here was funded by NASA grant NNX09AB22G. The CH3CN measurements were supported by the Austrian Research Promotion Agency (FFG-ALR) and the Tiroler Zukunftstiftung, and were carried out with the help\nof T. Mikoviny, M. Graus, A. Hansel and T. D. Maerk. The\nHCN instrument was run by J. Crounse and A. Kuerten. We\ngratefully acknowledge the ARCTAS crew and science team, and\nthe team of laboratory technicians and staff at UC-Irvine, especially B. Chisholm, R. Day, J. Glabe, G. Liu, B. Love, and A. Ly. We also thank E. Atlas (University of Miami) for updated alkyl nitrate calibrations, C. Wiedinmyer (NCAR) for help with the MODIS data acquisition, R. Hornbrook for helpful discussions, and two anonymous reviewers.\n\nPublished - Simpson2011p15738Atmos_Chem_Phys.pdf
", "abstract": "Boreal regions comprise about 17% of the global land area, and they both affect and are influenced by climate change. To better understand boreal forest fire emissions and plume evolution, 947 whole air samples were collected aboard the NASA DC-8 research aircraft in summer 2008 as part of the ARCTAS-B field mission, and analyzed for 79 non-methane volatile organic compounds (NMVOCs) using gas chromatography. Together with simultaneous measurements of CO_2, CO, CH_4, CH_2O, NO_2, NO, HCN and CH_3CN, these measurements represent the most comprehensive assessment of trace gas emissions from boreal forest fires to date. Based on 105 air samples collected in fresh Canadian smoke plumes, 57 of the 80 measured NMVOCs (including CH_2O) were emitted from the fires, including 45 species that were quantified from boreal forest fires for the first time. After CO_2, CO and CH_4, the largest emission factors (EFs) for individual species were formaldehyde (2.1 \u00b1 0.2 g kg^(\u22121)), followed by methanol, NO_2, HCN, ethene, \u03b1-pinene, \u03b2-pinene, ethane, benzene, propene, acetone and CH_3CN. Globally, we estimate that boreal forest fires release 2.4 \u00b1 0.6 Tg C yr^(\u22121) in the form of NMVOCs, with approximately 41% of the carbon released as C_1-C_2 NMVOCs and 21% as pinenes. These are the first reported field measurements of monoterpene emissions from boreal forest fires, and we speculate that the pinenes, which are relatively heavy molecules, were detected in the fire plumes as the result of distillation of stored terpenes as the vegetation is heated. Their inclusion in smoke chemistry models is expected to improve model predictions of secondary organic aerosol (SOA) formation. The fire-averaged EF of dichloromethane or CH_2Cl_2, (6.9 \u00b1 8.6) \u00d7 10^(\u22124)gkg^(\u22121), was not significantly different from zero and supports recent findings that its global biomass burning source appears to have been overestimated. Similarly, we found no evidence for emissions of chloroform (CHCl_3) or methyl chloroform (CH_3CCl_3) from boreal forest fires. The speciated hydrocarbon measurements presented here show the importance of carbon released by short-chain NMVOCs, the strong contribution of pinene emissions from boreal forest fires, and the wide range of compound classes in the most abundantly emitted NMVOCs, all of which can be used to improve biomass burning inventories in local/global models and reduce uncertainties in model estimates of trace gas emissions and their impact on the atmosphere.", "date": "2011-07-07", "date_type": "published", "publication": "Atmospheric Chemistry and Physics", "volume": "11", "number": "13", "publisher": "European Geosciences Union", "pagerange": "6445-6463", "id_number": "CaltechAUTHORS:20110912-114757018", "issn": "1680-7316", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20110912-114757018", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "California Air Resources Board" }, { "agency": "NASA", "grant_number": "NNX09AB22G" }, { "agency": "Austrian Research Promotion Agency (FFG-ALR)" }, { "agency": "Tiroler Zukunftstiftung" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/acp-11-6445-2011", "primary_object": { "basename": "Simpson2011p15738Atmos_Chem_Phys.pdf", "url": "https://authors.library.caltech.edu/records/yqqw2-3qw43/files/Simpson2011p15738Atmos_Chem_Phys.pdf" }, "resource_type": "article", "pub_year": "2011", "author_list": "Simpson, I. J.; Akagi, S. K.; et el." }, { "id": "https://authors.library.caltech.edu/records/4d762-kgh43", "eprint_id": 24385, "eprint_status": "archive", "datestamp": "2023-08-22 02:56:52", "lastmod": "2023-10-23 22:39:13", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Morino-I", "name": { "family": "Morino", "given": "I." } }, { "id": "Uchino-O", "name": { "family": "Uchino", "given": "O." } }, { "id": "Inoue-M", "name": { "family": "Inoue", "given": "M." } }, { "id": "Yoshida-Y", "name": { "family": "Yoshida", "given": "Y." } }, { "id": "Yokota-T", "name": { "family": "Yokota", "given": "T." } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Toon-G-C", "name": { "family": "Toon", "given": "G. C." }, "orcid": "0000-0003-4174-7541" }, { "id": "Wunch-D", "name": { "family": "Wunch", "given": "D." }, "orcid": "0000-0002-4924-0377" }, { "id": "Roehl-C-M", "name": { "family": "Roehl", "given": "C. M." }, "orcid": "0000-0001-5383-8462" }, { "id": "Notholt-J", "name": { "family": "Notholt", "given": "J." } }, { "id": "Warneke-T", "name": { "family": "Warneke", "given": "T." }, "orcid": "0000-0001-5185-3415" }, { "id": "Messerschmidt-J", "name": { "family": "Messerschmidt", "given": "J." } }, { "id": "Griffith-D-W-T", "name": { "family": "Griffith", "given": "D. W. T." }, "orcid": "0000-0002-7986-1924" }, { "id": "Deutscher-N-M", "name": { "family": "Deutscher", "given": "N. M." }, "orcid": "0000-0002-2906-2577" }, { "id": "Sherlock-V", "name": { "family": "Sherlock", "given": "V." } }, { "id": "Connor-B", "name": { "family": "Connor", "given": "B." } }, { "id": "Robinson-J", "name": { "family": "Robinson", "given": "J." } }, { "id": "Sussman-R", "name": { "family": "Sussman", "given": "R." } }, { "id": "Rettinger-M", "name": { "family": "Rettinger", "given": "M." } } ] }, "title": "Preliminary validation of column-averaged volume mixing ratios of carbon dioxide and methane retrieved from GOSAT\n short-wavelength infrared spectra", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2011 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: 26 November 2010; Published in Atmos. Meas. Tech. Discuss.: 8 December 2010. Revised: 25 April 2011; Accepted: 19 May 2011; Published: 15 June 2011. \n\nWe express our sincere thanks to the members\nof the NIES GOSAT project office, data algorithm team,\natmospheric transport modeling team for their useful comments. We thank Nobuyuki Kikuchi in NIES and Komei Yamaguchi in the Japan Weather Association for plotting the data. We would like to thank anonymous referees and the associated editor for improving this paper. This work was funded by the Ministry of the Environment in Japan. We also thank NASA's Terrestrial Ecology Program and the Orbiting Carbon Observatory for their support of TCCON, and acknowledge support from the EU within the projects\nGEOMON and IMECC. The Lauder TCCON measurements are\nfunded by New Zealand Foundation for Research, Science and\nTechnology contracts CO1X0204 and CO1X0406. We thank\nthe members of RAMCES team at LSCE (Gif-sur-Yvette) for\nmaintaining the FTS at the Trainou station and providing station logistics.\nEdited by: G. Stiller.\n\nPublished - Morino2011p14647Atmos_Meas_Tech.pdf
", "abstract": "Column-averaged volume mixing ratios of carbon dioxide and methane retrieved from the Greenhouse gases Observing SATellite (GOSAT) Short-Wavelength InfraRed observation (GOSAT SWIR X_(CO_2) and X_(CH_4) were compared with the reference calibrated data obtained by ground-based high-resolution Fourier Transform Spectrometers (g-b FTSs) participating in the Total Carbon Column Observing Network (TCCON).\n\nPreliminary results are as follows: the GOSAT SWIR X_(CO_2) and X_(CH_4) (Version 01.xx) are biased low by 8.85 \u00b1 4.75 ppm (2.3 \u00b1 1.2 %) and 20.4 \u00b1 18.9 ppb (1.2 \u00b1 1.1 %), respectively. The standard deviation of the GOSAT SWIR XCO2 and XCH4 is about 1 % (1 \u03c3) after correcting the negative biases of X_(CO_2) and X_(CH_4) by 8.85 ppm and 20.4 ppb, respectively. The latitudinal distributions of zonal means of the GOSAT SWIR X_(CO_2) and X_(CH_4) show similar features to those of the g-b FTS data except for the negative biases in the GOSAT data.", "date": "2011-06-15", "date_type": "published", "publication": "Atmospheric Measurement Techniques", "volume": "4", "number": "6", "publisher": "European Geosciences Union", "pagerange": "1061-1076", "id_number": "CaltechAUTHORS:20110712-113729884", "issn": "1867-1381", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20110712-113729884", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Ministry of the Environment (Japan)" }, { "agency": "NASA Orbiting Carbon Observatory" }, { "agency": "European Union (EU)" }, { "agency": "New Zealand Foundation for Research", "grant_number": "CO1X0204" }, { "agency": "New Zealand Foundation for Research", "grant_number": "CO1X0406" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/amt-4-1061-2011", "primary_object": { "basename": "Morino2011p14647Atmos_Meas_Tech.pdf", "url": "https://authors.library.caltech.edu/records/4d762-kgh43/files/Morino2011p14647Atmos_Meas_Tech.pdf" }, "resource_type": "article", "pub_year": "2011", "author_list": "Morino, I.; Uchino, O.; et el." }, { "id": "https://authors.library.caltech.edu/records/9pchg-8b375", "eprint_id": 23816, "eprint_status": "archive", "datestamp": "2023-08-22 02:46:13", "lastmod": "2023-10-23 20:02:32", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Wunch-D", "name": { "family": "Wunch", "given": "Debra" }, "orcid": "0000-0002-4924-0377" }, { "id": "Toon-G-C", "name": { "family": "Toon", "given": "Geoffrey C." }, "orcid": "0000-0003-4174-7541" }, { "id": "Blavier-J-F-L", "name": { "family": "Blavier", "given": "Jean-Fran\u00e7ois L." } }, { "id": "Washenfelder-R-A", "name": { "family": "Washenfelder", "given": "Rebecca A." }, "orcid": "0000-0002-8106-3702" }, { "id": "Notholt-J", "name": { "family": "Notholt", "given": "Justus" } }, { "id": "Connor-B-J", "name": { "family": "Connor", "given": "Brian J." } }, { "id": "Griffith-D-W-T", "name": { "family": "Griffith", "given": "David W. T." }, "orcid": "0000-0002-7986-1924" }, { "id": "Sherlock-V", "name": { "family": "Sherlock", "given": "Vanessa" } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "The Total Carbon Column Observing Network", "ispublished": "pub", "full_text_status": "public", "keywords": "greenhouse gases; carbon cycle; Fourier transform \nspectrometry", "note": "\u00a9 2011 Royal Society. 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 work is properly cited. \n\nNCEP reanalysis data are provided by the NOAA/OAR/ESRL \nPSD, Boulder, CO, USA, from their website at http://www.cdc.noaa.gov/. US funding for TCCON comes from NASA's Terrestrial Ecology Program (NNX08A186G), the Orbiting Carbon Observatory Program (NAS7-03001), the DOE/ARM Program and the Atmospheric CO2 Observations from Space Program. Some of the research described in this paper was performed at the Jet Propulsion Laboratory, California\nInstitute of Technology, under a contract with the National Aeronautics and Space Administration. We acknowledge funding within the EU projects GEOMON and IMECC and the grant from the Deutsche Forschungsgemeinschaft (DFG) NO 404/14-1. Lauder measurements are supported by New Zealand Foundation of Research Science and Technology contracts C01X0204 and C01X0406. Australian funding is from the Australian Research Council, DP0879468 and LP0562346.\n\nPublished - Wunch2011p13923Philos_Transact_A_Math_Phys_Eng_Sci.pdf
", "abstract": "A global network of ground-based Fourier transform spectrometers has been founded to remotely measure column abundances of CO_2, CO, CH_4, N_(2)O and other molecules that absorb in the near-infrared. These measurements are directly comparable with the near-infrared total column measurements from space-based instruments. With stringent requirements on the instrumentation, acquisition procedures, data processing and calibration, the Total Carbon Column Observing Network (TCCON) achieves an\naccuracy and precision in total column measurements that is unprecedented for remotesensing observations (better than 0.25% for CO_2). This has enabled carbon-cycle science\ninvestigations using the TCCON dataset, and allows the TCCON to provide a link between satellite measurements and the extensive ground-based in situ network.", "date": "2011-05-28", "date_type": "published", "publication": "Philosophical Transactions A: Mathematical, Physical and Engineering Sciences", "volume": "369", "number": "1943", "publisher": "Royal Society of London", "pagerange": "2087-2112", "id_number": "CaltechAUTHORS:20110526-151219533", "issn": "1364-503X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20110526-151219533", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NNX08A186G" }, { "agency": "NASA", "grant_number": "NAS7-03001" }, { "agency": "Department of Energy (DOE)" }, { "agency": "EU projects GEOMON and IMECC" }, { "agency": "Deutsche Forschungsgemeinschaft (DFG)", "grant_number": "404/14-1" }, { "agency": "New Zealand Foundation of Research Science and Technology", "grant_number": "C01X0204" }, { "agency": "New Zealand Foundation of Research Science and Technology", "grant_number": "C01X0406" }, { "agency": "Australian Research Council", "grant_number": "DP0879468" }, { "agency": "Australian Research Council", "grant_number": "LP0562346" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1098/rsta.2010.0240", "primary_object": { "basename": "Wunch2011p13923Philos_Transact_A_Math_Phys_Eng_Sci.pdf", "url": "https://authors.library.caltech.edu/records/9pchg-8b375/files/Wunch2011p13923Philos_Transact_A_Math_Phys_Eng_Sci.pdf" }, "resource_type": "article", "pub_year": "2011", "author_list": "Wunch, Debra; Toon, Geoffrey C.; et el." }, { "id": "https://authors.library.caltech.edu/records/75btm-hbb64", "eprint_id": 23825, "eprint_status": "archive", "datestamp": "2023-08-22 02:44:18", "lastmod": "2023-10-23 20:02:54", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Carn-S-A", "name": { "family": "Carn", "given": "S. A." } }, { "id": "Froyd-K-D", "name": { "family": "Froyd", "given": "K. D." } }, { "id": "Anderson-B-E", "name": { "family": "Anderson", "given": "B. E." } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P." }, "orcid": "0000-0002-6126-3854" }, { "id": "Crounse-J-D", "name": { "family": "Crounse", "given": "J." }, "orcid": "0000-0001-5443-729X" }, { "id": "Spencer-K", "name": { "family": "Spencer", "given": "K." } }, { "id": "Dibb-J-E", "name": { "family": "Dibb", "given": "J. E." }, "orcid": "0000-0003-3096-7709" }, { "id": "Krotkov-N-A", "name": { "family": "Krotkov", "given": "N. A." } }, { "id": "Browell-E-V", "name": { "family": "Browell", "given": "E. V." } }, { "id": "Hair-J-W", "name": { "family": "Hair", "given": "J. W." }, "orcid": "0000-0002-9672-1237" }, { "id": "Diskin-G", "name": { "family": "Diskin", "given": "G." } }, { "id": "Sachse-G", "name": { "family": "Sachse", "given": "G." } }, { "id": "Vay-S-A", "name": { "family": "Vay", "given": "S. A." } } ] }, "title": "In situ measurements of tropospheric volcanic plumes in Ecuador and Colombia during TC^4", "ispublished": "pub", "full_text_status": "public", "keywords": "volcanic plumes; Ecuador; Colombia; sulfur dioxide; sulfate aerosol", "note": "\u00a9 2011 American Geophysical Union. \n\nReceived 6 July 2010; accepted 16 February 2011; published 10 May 2011. \n\nWe acknowledge NASA funding for Aura validation (contracts NNG06GJ02G and NNX09AJ40G). Mark Schoeberl spearheaded the effort to intercept the volcanic plumes during the TC4\nscience flights. We thank Santiago Arellano for assistance with flight planning and volcanic activity reports during the TC4 mission and Cynthia Twohy for providing CVI data. The NOAA Air Resources Laboratory is acknowledged for the provision of the HYSPLIT transport and dispersion model and READY website (http://www.arl.noaa.gov/ready.html). We\nthank R. S. Martin and an anonymous reviewer for thorough reviews that greatly improved the paper.\n\nPublished - Carn2011p13961J_Geophys_Res-Atmos.pdf
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Supplemental Material - 2010jd014718-fs05.tif
Supplemental Material - 2010jd014718-readme.txt
", "abstract": "A NASA DC-8 research aircraft penetrated tropospheric gas and aerosol plumes sourced from active volcanoes in Ecuador and Colombia during the Tropical Composition, Cloud and Climate Coupling (TC^4) mission in July\u2013August 2007. The likely source volcanoes were Tungurahua (Ecuador) and Nevado del Huila (Colombia). The TC^4 data provide rare insight into the chemistry of volcanic plumes in the tropical troposphere and permit a comparison of SO_2 column amounts measured by the Ozone Monitoring Instrument (OMI) on the Aura satellite with in situ SO_2 measurements. Elevated concentrations of SO_2, sulfate aerosol, and particles were measured by DC-8 instrumentation in volcanic outflow at altitudes of 3\u20136 km. Estimated plume ages range from ~2 h at Huila to ~22\u201348 h downwind of Ecuador. The plumes contained sulfate-rich accumulation mode particles that were variably neutralized and often highly acidic. A significant fraction of supermicron volcanic ash was evident in one plume. In-plume O_3 concentrations were ~70%\u201380% of ambient levels downwind of Ecuador, but data are insufficient to ascribe this to O_3 depletion via reactive halogen chemistry. The TC^4 data record rapid cloud processing of the Huila volcanic plume involving aqueous-phase oxidation of SO_2 by H_2O_2, but overall the data suggest average in-plume SO_2 to sulfate conversion rates of ~1%\u20132% h^(\u22121). SO_2 column amounts measured in the Tungurahua plume (~0.1\u20130.2 Dobson units) are commensurate with average SO_2 columns retrieved from OMI measurements in the volcanic outflow region in July 2007. The TC^4 data set provides further evidence of the impact of volcanic emissions on tropospheric acidity and oxidizing capacity.", "date": "2011-05-10", "date_type": "published", "publication": "Journal of Geophysical Research D", "volume": "116", "publisher": "American Geophysical Union", "pagerange": "Art. No. D00J24", "id_number": "CaltechAUTHORS:20110527-115645829", "issn": "0148-0227", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20110527-115645829", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NNG06GJ02G" }, { "agency": "NASA", "grant_number": "NNX09AJ40G" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2010JD014718", "primary_object": { "basename": "2010jd014718-fs02.tif", "url": "https://authors.library.caltech.edu/records/75btm-hbb64/files/2010jd014718-fs02.tif" }, "related_objects": [ { "basename": "2010jd014718-fs05.tif", "url": "https://authors.library.caltech.edu/records/75btm-hbb64/files/2010jd014718-fs05.tif" }, { "basename": "2010jd014718-readme.txt", "url": "https://authors.library.caltech.edu/records/75btm-hbb64/files/2010jd014718-readme.txt" }, { "basename": "Carn2011p13961J_Geophys_Res-Atmos.pdf", "url": "https://authors.library.caltech.edu/records/75btm-hbb64/files/Carn2011p13961J_Geophys_Res-Atmos.pdf" }, { "basename": "2010jd014718-fs01.tif", "url": "https://authors.library.caltech.edu/records/75btm-hbb64/files/2010jd014718-fs01.tif" }, { "basename": "2010jd014718-fs03.jpg", "url": "https://authors.library.caltech.edu/records/75btm-hbb64/files/2010jd014718-fs03.jpg" }, { "basename": "2010jd014718-fs04.jpg", "url": "https://authors.library.caltech.edu/records/75btm-hbb64/files/2010jd014718-fs04.jpg" }, { "basename": "medium.png", "url": "https://authors.library.caltech.edu/records/75btm-hbb64/files/medium.png" }, { "basename": "small.png", "url": "https://authors.library.caltech.edu/records/75btm-hbb64/files/small.png" } ], "resource_type": "article", "pub_year": "2011", "author_list": "Carn, S. A.; Froyd, K. D.; et el." }, { "id": "https://authors.library.caltech.edu/records/75rtb-xba43", "eprint_id": 23743, "eprint_status": "archive", "datestamp": "2023-08-22 02:32:32", "lastmod": "2023-10-23 19:54:24", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Keppel-Aleks-G", "name": { "family": "Keppel-Aleks", "given": "G." } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Schneider-T", "name": { "family": "Schneider", "given": "T." }, "orcid": "0000-0001-5687-2287" } ] }, "title": "Sources of variations in total column carbon dioxide", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2011 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: 11 November 2010. Published in Atmos. Chem. Phys. Discuss.: 16 December 2010. Revised: 15 March 2011. Accepted: 24 March 2011. Published: 18 April 2011. Article first published online: 21 Jun 2010. \n\nWe thank Peter Rayer and Dietrich Feist for helpful reviews of this manuscript. Support for this work from the NASA Carbon Cycle Program grant NNX08AI86G is gratefully acknowledged. GKA acknowledges support from a NSF graduate fellowship and an AAUW dissertation fellowship. The simulations shown were performed on Caltech's Division of Geological and Planetary Sciences Dell cluster. CarbonTracker 2009 data were provided by NOAA ESRL, Boulder, Colorado, USA from the\nwebsite at http://carbontracker.noaa.gov. \nEdited by: C. Gerbig.\n\nPublished - KeppelAleks2011p13841Atmos_Chem_Phys.pdf
", "abstract": "Observations of gradients in the total CO_2 column,\n(CO2), are expected to provide improved constraints\non surface fluxes of CO_2. Here we use a general circulation\nmodel with a variety of prescribed carbon fluxes to investigate how variations in (CO_2) arise. On diurnal scales, variations are small and are forced by both local fluxes and advection. On seasonal scales, gradients are set by the north-south flux distribution. On synoptic scales, variations arise due to large-scale eddy-driven disturbances of the meridional gradient. In this case, because variations in (CO_2) are tied to synoptic\nactivity, significant correlations exist between (CO_2)\nand dynamical tracers. We illustrate how such correlations\ncan be used to describe the north-south gradients of (CO_2)\nand the underlying fluxes on continental scales. These simulations suggest a novel analysis framework for using column observations in carbon cycle science.", "date": "2011-04-18", "date_type": "published", "publication": "Atmospheric Chemistry and Physics", "volume": "11", "number": "8", "publisher": "European Geosciences Union", "pagerange": "3581-3593", "id_number": "CaltechAUTHORS:20110520-080425147", "issn": "1680-7316", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20110520-080425147", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NNX08AI86G" }, { "agency": "NSF Graduate Fellowship" }, { "agency": "AAUW Dissertation Fellowship" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/acp-11-3581-2011", "primary_object": { "basename": "KeppelAleks2011p13841Atmos_Chem_Phys.pdf", "url": "https://authors.library.caltech.edu/records/75rtb-xba43/files/KeppelAleks2011p13841Atmos_Chem_Phys.pdf" }, "resource_type": "article", "pub_year": "2011", "author_list": "Keppel-Aleks, G.; Wennberg, P. O.; et el." }, { "id": "https://authors.library.caltech.edu/records/etwzy-hjd30", "eprint_id": 24206, "eprint_status": "archive", "datestamp": "2023-08-22 02:29:07", "lastmod": "2023-10-23 20:23:11", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Huang-M", "name": { "family": "Huang", "given": "M." } }, { "id": "Carmichael-G-R", "name": { "family": "Carmichael", "given": "G. R." } }, { "id": "Spak-S-N", "name": { "family": "Spak", "given": "S. N." } }, { "id": "Adhikary-B", "name": { "family": "Adhikary", "given": "B." } }, { "id": "Kulkarni-S", "name": { "family": "Kulkarni", "given": "S." } }, { "id": "Cheng-Y", "name": { "family": "Cheng", "given": "Y." } }, { "id": "Wei-C", "name": { "family": "Wei", "given": "C." } }, { "id": "Tang-Y", "name": { "family": "Tang", "given": "Y." } }, { "id": "D'Allura-A", "name": { "family": "D'Allura", "given": "A." } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Huey-G-L", "name": { "family": "Huey", "given": "G. L." } }, { "id": "Dibb-J-E", "name": { "family": "Dibb", "given": "J. E." }, "orcid": "0000-0003-3096-7709" }, { "id": "Jimenez-J-L", "name": { "family": "Jimenez", "given": "J. L." }, "orcid": "0000-0001-6203-1847" }, { "id": "Cubison-M-J", "name": { "family": "Cubison", "given": "M. J." } }, { "id": "Weinheimer-A-J", "name": { "family": "Weinheimer", "given": "A. J." }, "orcid": "0000-0001-6175-8286" }, { "id": "Kaduwela-A", "name": { "family": "Kaduwela", "given": "A." } }, { "id": "Cai-C", "name": { "family": "Cai", "given": "C." } }, { "id": "Wong-M", "name": { "family": "Wong", "given": "M." } }, { "id": "Pierce-R-B", "name": { "family": "Pierce", "given": "R. Bradley" } }, { "id": "Al-Saadi-J-A", "name": { "family": "Al-Saadi", "given": "J. A." } }, { "id": "Streets-D-G", "name": { "family": "Streets", "given": "D. G." } }, { "id": "Zhang-Q", "name": { "family": "Zhang", "given": "Q." } } ] }, "title": "Multi-scale modeling study of the source contributions to near-surface ozone and sulfur oxides levels over California during the ARCTAS-CARB period", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 Author(s) 2011. 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: 22 October 2010; Published in Atmos. Chem. Phys. Discuss.: 12 November 2010; Revised: 7 March 2011; Accepted: 27 March 2011; Published: 4 April 2011. \n\nWe would like to thank the ARCTAS science team and two anonymous reviewers. We thank Tianfeng Chai (NOAA/OAR/ARL) for helping with the STEM adjoint model. This work was supported by a NASA award (NNX08AH56G). Jose L. Jimenez and Michael J. Cubisonwere supported by NASA NNX08AD39G. The authors would also like to acknowledge NOAA, the US EPA and CARB for support of the ground measurements. The views, opinions, and findings contained in this report are those of the author(s) and should not be construed as an official\nNOAA or US Government position, policy, or decision.\n\nPublished - Huang2011p14312Atmos_Chem_Phys.pdf
Supplemental Material - acp-11-3173-2011-supplement.pdf
", "abstract": "Chronic high surface ozone (O_3) levels and the increasing sulfur oxides (SO_x = SO_2 + SO_4) ambient concentrations over South Coast (SC) and other areas of California (CA) are affected by both local emissions and long-range transport. In this paper, multi-scale tracer, full-chemistry and adjoint simulations using the STEM atmospheric chemistry model are conducted to assess the contribution of local emission sourcesto SC O_3 and to evaluate the impacts of transported sulfur and local emissions on the SC sulfur budgetduring the ARCTAS-CARB experiment period in 2008. Sensitivity simulations quantify contributions of biogenic and fire emissions to SC O_3 levels. California biogenic and fire emissions contribute 3\u20134 ppb to near-surface O_3 over SC, with larger contributions to other regions in CA. During a long-range transport event from Asia starting from 22 June, high SO_x levels (up to ~0.7 ppb of SO_2 and ~1.3 ppb of SO_4) is observed above ~6 km, but they did not affect CA surface air quality. The elevated SO_x observed at 1\u20134 km is estimated to enhance surface SO_x over SC by ~0.25 ppb (upper limit) on ~24 June. The near-surface SO_x levels over SC during the flight week are attributed mostly to local emissions. Two anthropogenic SO_x emission inventories (EIs) from the California Air Resources Board (CARB) and the US Environmental Protection Agency (EPA) are compared and applied in 60 km and 12 km chemical transport simulations, and the results are compared withobservations. The CARB EI shows improvements over the National Emission Inventory (NEI) by EPA, but generally underestimates surface SC SO_x by about a factor of two. Adjoint sensitivity analysis indicated that SO_2 levels at 00:00 UTC (17:00 local time) at six SC surface sites were influenced by previous day maritime emissions over the ocean, the terrestrial emissions over nearby urban areas, and by transported SO_2 from the north through both terrestrial and maritime areas. Overall maritime emissions contribute 10\u201370% of SO2 and 20\u201360% fine SO_4 on-shore and over the most terrestrial areas, with contributions decreasing with in-land distance from the coast. Maritime emissions also modify the photochemical environment, shifting O_3 production over coastal SC to more VOC-limited conditions. These suggest an important role for shipping emission controls in reducing fine particle and O_3 concentrations in SC.", "date": "2011-04-04", "date_type": "published", "publication": "Atmospheric Chemistry and Physics", "volume": "11", "number": "7", "publisher": "European Geosciences Union", "pagerange": "3173-3194", "id_number": "CaltechAUTHORS:20110624-134538082", "issn": "1680-7316", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20110624-134538082", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NNX08AH56G" }, { "agency": "NASA", "grant_number": "NNX08AD39G" }, { "agency": "National Oceanic and Atmospheric Administration (NOAA)" }, { "agency": "Environmental Protection Agency (EPA)" }, { "agency": "California Air Resources Board" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/acp-11-3173-2011", "primary_object": { "basename": "Huang2011p14312Atmos_Chem_Phys.pdf", "url": "https://authors.library.caltech.edu/records/etwzy-hjd30/files/Huang2011p14312Atmos_Chem_Phys.pdf" }, "related_objects": [ { "basename": "acp-11-3173-2011-supplement.pdf", "url": "https://authors.library.caltech.edu/records/etwzy-hjd30/files/acp-11-3173-2011-supplement.pdf" } ], "resource_type": "article", "pub_year": "2011", "author_list": "Huang, M.; Carmichael, G. R.; et el." }, { "id": "https://authors.library.caltech.edu/records/acrpx-mmr75", "eprint_id": 47252, "eprint_status": "archive", "datestamp": "2023-08-22 02:14:00", "lastmod": "2023-10-26 20:26:35", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Paulot-F", "name": { "family": "Paulot", "given": "F." }, "orcid": "0000-0001-7534-4922" }, { "id": "Wunch-D", "name": { "family": "Wunch", "given": "D." }, "orcid": "0000-0002-4924-0377" }, { "id": "Crounse-J-D", "name": { "family": "Crounse", "given": "J. D." }, "orcid": "0000-0001-5443-729X" }, { "id": "Toon-G-C", "name": { "family": "Toon", "given": "G. C." }, "orcid": "0000-0003-4174-7541" }, { "id": "Miller-D-B", "name": { "family": "Miller", "given": "D. B." } }, { "id": "DeCarlo-P-F", "name": { "family": "DeCarlo", "given": "P. F." } }, { "id": "Vigouroux-C", "name": { "family": "Vigouroux", "given": "C." } }, { "id": "Deutscher-N-M", "name": { "family": "Deutscher", "given": "N. M." }, "orcid": "0000-0002-2906-2577" }, { "id": "Gonz\u00e1lez-Abad-G", "name": { "family": "Gonz\u00e1lez-Abad", "given": "G." }, "orcid": "0000-0002-8090-6480" }, { "id": "Notholt-J", "name": { "family": "Notholt", "given": "J." } }, { "id": "Warneke-T", "name": { "family": "Warneke", "given": "T." }, "orcid": "0000-0001-5185-3415" }, { "id": "Hannigan-J-W", "name": { "family": "Hannigan", "given": "J. W." } }, { "id": "Warneke-C", "name": { "family": "Warneke", "given": "C." } }, { "id": "de-Gouw-J-A", "name": { "family": "de Gouw", "given": "J. A." }, "orcid": "0000-0002-0385-1826" }, { "id": "Dunlea-E-J", "name": { "family": "Dunlea", "given": "E. J." } }, { "id": "De-Mazi\u00e8re-M", "name": { "family": "De Mazi\u00e8re", "given": "M." } }, { "id": "Griffith-D-W-T", "name": { "family": "Griffith", "given": "D. W. T." }, "orcid": "0000-0002-7986-1924" }, { "id": "Bernath-P", "name": { "family": "Bernath", "given": "P." } }, { "id": "Jimenez-J-L", "name": { "family": "Jimenez", "given": "J. L." }, "orcid": "0000-0001-6203-1847" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "Importance of secondary sources in the atmospheric budgets of formic and acetic acids", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2011 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: 18 September 2010. Published in Atmos. Chem. Phys. Discuss.: 20 October 2010. Revised: 23 February 2011. Accepted: 25 February 2011. Published: 4 March 2011. \n\nThe authors thank two anonymous referees and T. Stavrakou for their constructive comments. FP is supported by a NASA Earth and Space Science fellowship. GGA is supported by the Wild Fund and the National Center for Earth Observation (NCEO). DBM acknowledges support from NASA under Grant NNX10AG65G. The National Center for Atmospheric Research is supported by the National Science Foundation. The NCAR FTS observation program at Thule (GR) is supported under contract by the National Aeronautics and Space Administration (NASA). This work is also supported by the NSF Office of Polar\nPrograms (OPP). PFD, EJD and JLJ were supported by NASA\nNNX08AD39G and NOAA NA08OAR4310565. The authors wish to thank the Danish Meteorological Institute for support at\nthe Thule site. JN acknowledges funding by the grant from the Deutsche Forschungsgemeinschaft (DFG) NO 404/14-1. NMD\nand DWTG acknowledge support from the Australian Department\nof Innovation, Industry, Science and Research, Internation Science Linkage under Grant CG130014. CV and MDM acknowledge\nthe PRODEX project SECPEA and the project AGACC from\nthe Belgian Science Policy Office (contracts SD/AT/O1A and\nSD/AT/01B) for supporting the FTIR experiment at La R\u00e9union.\nPart of this work was performed at the Jet Propulsion Laboratory, California Institute of Technology, under contract with NASA. The ACE mission is supported primarily by the Canadian Space Agency. Some support was also provided by the UK Natural Environment Research Council (NERC), through the National Centre for Earth Observation (NCEO). Measurements of FA and AA during the INTEX-B and Milagro missions were supported by NASA under Grant NNG06GB32B. The authors are grateful to Stephen Arnold and Dominick Spracklen for providing the marine isoprene fluxes, and to Sheryl Akagi and Robert Yokelson for\nproviding updated biomass burning and biofuel emission factors. The numerical simulations for this research were performed on Caltech's Division of Geological and Planetary Sciences Dell cluster.\nEdited by: J. P. D. Abbatt.\n\nPublished - acp-11-1989-2011.pdf
Supplemental Material - acp-11-1989-2011-supplement.pdf
", "abstract": "We present a detailed budget of formic and acetic acids, two of the most abundant trace gases in the atmosphere. Our bottom-up estimate of the global source of formic and acetic acids are ~1200 and ~1400 Gmol yr^(\u22121), dominated by photochemical oxidation of biogenic volatile organic compounds, in particular isoprene. Their sinks are dominated by wet and dry deposition. We use the GEOS-Chem chemical transport model to evaluate this budget against an extensive suite of measurements from ground, ship and satellite-based Fourier transform spectrometers, as well as from several aircraft campaigns over North America. The model captures the seasonality of formic and acetic acids well but generally underestimates their concentration, particularly in the Northern midlatitudes. We infer that the source of both carboxylic acids may be up to 50% greater than our estimate and report evidence for a long-lived missing secondary source of carboxylic acids that may be associated with the aging of organic aerosols. Vertical profiles of formic acid in the upper troposphere support a negative temperature dependence of the reaction between formic acid and the hydroxyl radical as suggested by several theoretical studies.", "date": "2011-03-04", "date_type": "published", "publication": "Atmospheric Chemistry and Physics", "volume": "11", "number": "5", "publisher": "European Geosciences Union", "pagerange": "1989-2013", "id_number": "CaltechAUTHORS:20140716-074539855", "issn": "1680-7316", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140716-074539855", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA Earth and Space Science Fellowship" }, { "agency": "Wild Fund and National Center for Earth Observation (NCEO)" }, { "agency": "NASA", "grant_number": "NNX10AG65G" }, { "agency": "NSF" }, { "agency": "NASA", "grant_number": "NNX08AD39G" }, { "agency": "National Oceanic and Atmospheric Administration (NOAA)", "grant_number": "NA08OAR4310565" }, { "agency": "Deutsche Forschungsgemeinschaft (DFG)", "grant_number": "404/14-1" }, { "agency": "Department of Innovation, Industry, Science and Research (Australia)", "grant_number": "CG130014" }, { "agency": "Belgian Science Policy Office (BELSPO)", "grant_number": "SD/AT/O1A" }, { "agency": "Belgian Science Policy Office (BELSPO)", "grant_number": "SD/AT/01B" }, { "agency": "NASA/JPL/Caltech" }, { "agency": "Canadian Space Agency (CSA)" }, { "agency": "Natural Environment Research Council (NERC)" }, { "agency": "National Centre for Earth Observation (NCEO)" }, { "agency": "NASA", "grant_number": "NNG06GB32B" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/acp-11-1989-2011", "primary_object": { "basename": "acp-11-1989-2011-supplement.pdf", "url": "https://authors.library.caltech.edu/records/acrpx-mmr75/files/acp-11-1989-2011-supplement.pdf" }, "related_objects": [ { "basename": "acp-11-1989-2011.pdf", "url": "https://authors.library.caltech.edu/records/acrpx-mmr75/files/acp-11-1989-2011.pdf" } ], "resource_type": "article", "pub_year": "2011", "author_list": "Paulot, F.; Wunch, D.; et el." }, { "id": "https://authors.library.caltech.edu/records/nm63h-ap829", "eprint_id": 23069, "eprint_status": "archive", "datestamp": "2023-08-22 02:06:57", "lastmod": "2023-10-23 17:52:35", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Reuter-M", "name": { "family": "Reuter", "given": "M." } }, { "id": "Bovensmann-H", "name": { "family": "Bovensmann", "given": "H." } }, { "id": "Buchwitz-M", "name": { "family": "Buchwitz", "given": "M." } }, { "id": "Burrows-J-P", "name": { "family": "Burrows", "given": "J. P." } }, { "id": "Connor-B-J", "name": { "family": "Connor", "given": "B. J." } }, { "id": "Deutscher-N-M", "name": { "family": "Deutscher", "given": "N. M." }, "orcid": "0000-0002-2906-2577" }, { "id": "Griffith-D-W-T", "name": { "family": "Griffith", "given": "D. W. T." }, "orcid": "0000-0002-7986-1924" }, { "id": "Heymann-J", "name": { "family": "Heymann", "given": "J." } }, { "id": "Keppel-Aleks-G", "name": { "family": "Keppel-Aleks", "given": "G." } }, { "id": "Messerschmidt-J", "name": { "family": "Messerschmidt", "given": "J." } }, { "id": "Notholt-J", "name": { "family": "Notholt", "given": "J." } }, { "id": "Petri-C", "name": { "family": "Petri", "given": "C." }, "orcid": "0000-0002-7010-5532" }, { "id": "Robinson-J", "name": { "family": "Robinson", "given": "J." } }, { "id": "Schneising-O", "name": { "family": "Schneising", "given": "O." } }, { "id": "Sherlock-V", "name": { "family": "Sherlock", "given": "V." } }, { "id": "Velazco-V", "name": { "family": "Velazco", "given": "V." } }, { "id": "Warneke-T", "name": { "family": "Warneke", "given": "T." }, "orcid": "0000-0001-5185-3415" }, { "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" } ] }, "title": "Retrieval of atmospheric CO_2 with enhanced accuracy and precision from SCIAMACHY: Validation with FTS measurements and comparison with model results", "ispublished": "pub", "full_text_status": "public", "keywords": "carbon dioxide; CO2; SCIAMACHY; validation; satellite; atmosphere", "note": "\u00a9 2011 American Geophysical Union.\n\nReceived 13 September 2010; revised 16 November 2010; accepted 10 December 2010; published 23 February 2011.\n\nThis work was in part funded by ESA/\nESRIN (ADVANSE, GHG\u2010CCI), EU FP7 (MACC, CityZen), DLR\n(SADOS), and the state and the University of Bremen. We thank NOAA\nfor making available the CarbonTracker CO2 fields and ECMWF for providing\nthe meteorological data. TCCON is funded by the NASA terrestrial\ncarbon cycle program, grant NNX08AI86G. Lauder TCCON measurements\nare supported by New Zealand Foundation for Research Science\nand Technology contracts CO1X0204 and CO1X0406. We thank NASA\nfor making available the CALIPSO data and the GEMS project for providing\ntheir aerosol product. We further thank our reviewers for their helpful\nand valuable comments to improve this work. Many thanks are given to\nS. Pfeifer and J. Reuter for proofreading the manuscript.\n\nPublished - Reuter2011p13109J_Geophys_Res-Atmos.pdf
", "abstract": "The Bremen Optimal Estimation differential optical absorption spectroscopy (DOAS) (BESD) algorithm for satellite based retrievals of\n XCO_2 (the column-average dry-air mole fraction of atmospheric CO_2) has\n been applied to Scanning Imaging Absorption Spectrometer for\n Atmospheric Cartography (SCIAMACHY) data. It uses measurements in the\n O_2-A absorption band to correct for scattering of undetected clouds\n and aerosols. Comparisons with precise and accurate ground-based\n Fourier transform spectrometer (FTS) measurements at four Total Carbon\n Column Observing Network (TCCON) sites have been used to quantify the\n quality of the new SCIAMACHY XCO_2 data set. Additionally, the results\n have been compared to NOAA's assimilation system CarbonTracker. The\n comparisons show that the new retrieval meets the expectations from\n earlier theoretical studies. We find no statistically significant\n regional XCO_2 biases between SCIAMACHY and the FTS instruments.\n However, the standard error of the systematic differences is in the\n range of 0.2 ppm and 0.8 ppm. The XCO_2 single-measurement precision of\n 2.5 ppm is similar to theoretical estimates driven by instrumental\n noise. There are no significant differences found for the year-to-year\n increase as well as for the average seasonal amplitude between\n SCIAMACHY XCO_2 and the collocated FTS measurements. Comparison of the\n year-to-year increase and also of the seasonal amplitude of\n CarbonTracker exhibit significant differences with the corresponding\n FTS values at Darwin. Here the differences between SCIAMACHY and\n CarbonTracker are larger than the standard error of the SCIAMACHY\n values. The difference of the seasonal amplitude exceeds the\n significance level of 2 standard errors. Therefore, our results suggest\n that SCIAMACHY may provide valuable additional information about XCO_2,\n at least in regions with a low density of in situ measurements.", "date": "2011-02-23", "date_type": "published", "publication": "Journal of Geophysical Research D", "volume": "116", "number": "D4", "publisher": "American Geophysical Union", "pagerange": "Art. No. D04301", "id_number": "CaltechAUTHORS:20110323-090520553", "issn": "0148-0227", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20110323-090520553", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "European Space Agency (ESA)" }, { "agency": "European Union (EU)" }, { "agency": "Deutschland f\u00fcr Luft- und Raumfahrt (DLR)" }, { "agency": "State and the University of Bremen" }, { "agency": "NASA", "grant_number": "NNX08AI86G" }, { "agency": "New Zealand Foundation for Research Science and Technology", "grant_number": "CO1X0204" }, { "agency": "New Zealand Foundation for Research Science and Technology", "grant_number": "CO1X0406" }, { "agency": "European Space Research Institute (ESRIN)" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2010JD015047", "primary_object": { "basename": "Reuter2011p13109J_Geophys_Res-Atmos.pdf", "url": "https://authors.library.caltech.edu/records/nm63h-ap829/files/Reuter2011p13109J_Geophys_Res-Atmos.pdf" }, "resource_type": "article", "pub_year": "2011", "author_list": "Reuter, M.; Bovensmann, H.; et el." }, { "id": "https://authors.library.caltech.edu/records/v2nta-70y56", "eprint_id": 23905, "eprint_status": "archive", "datestamp": "2023-08-22 01:38:00", "lastmod": "2023-10-23 20:08:33", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Akagi-S-K", "name": { "family": "Akagi", "given": "S. K." } }, { "id": "Yokelson-R-J", "name": { "family": "Yokelson", "given": "R. J." }, "orcid": "0000-0002-8415-6808" }, { "id": "Wiedinmyer-C", "name": { "family": "Wiedinmyer", "given": "C." } }, { "id": "Alvarado-M-J", "name": { "family": "Alvarado", "given": "M. J." } }, { "id": "Reid-J-S", "name": { "family": "Reid", "given": "J. S." } }, { "id": "Karl-T", "name": { "family": "Karl", "given": "T." } }, { "id": "Crounse-J-D", "name": { "family": "Crounse", "given": "J. D." }, "orcid": "0000-0001-5443-729X" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "Emission factors for open and domestic biomass burning for use in atmospheric models", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2011 Author(s). \nPublished by Copernicus Publications on behalf of the European Geosciences Union.\nThis work is distributed\nunder the Creative Commons Attribution 3.0 License.\n\n\nReceived: 19 September 2010. Published in Atmos. Chem. Phys. Discuss.: 12 November 2010. Revised: 14 April 2011. Accepted: 15 April 2011. Published: 3 May 2011. \n\nWe thank Isobel Simpson, Don Blake, Andy Weinheimer, Armin Wisthaler, Guido van der Werf, Thijs van Leeuwen, Ian Burling, Tami Bond, Christoph Roden, and Ted Christian for advance data. We thank Jennifer Logan, Ed Hyer, Jim Reardon, John Graham, Mark Carroll, Angelika Heil, and Ben\nFoster, for helpful discussions. SKA thanks Paulette Middleton and GEIA for financial support. Akagi and Yokelson were supported by NSF grants ATM-0513055 and ATM-0936321.\n\nPublished - Akagi2011p14035Atmos_Chem_Phys.pdf
Supplemental Material - acp-11-4039-2011-supplement.zip
", "abstract": "Biomass burning (BB) is the second largest source of trace gases and the largest source of primary fine carbonaceous particles in the global troposphere. Many recent BB studies have provided new emission factor (EF) measurements. This is especially true for non-methane organic compounds (NMOC), which influence secondary organic aerosol (SOA) and ozone formation. New EF should improve regional to global BB emissions estimates and therefore, the input for atmospheric models. In this work we present an up-to-date, comprehensive tabulation of EF for known pyrogenic species based on measurements made in smoke that has cooled to ambient temperature, but not yet undergone significant photochemical processing. All EFs are converted to one standard form (g compound emitted per kg dry biomass burned) using the carbon mass balance method and they are categorized into 14 fuel or vegetation types. Biomass burning terminology is defined to promote consistency. We compile a large number of measurements of biomass consumption per unit area for important fire types and summarize several recent estimates of global biomass consumption by the major types of biomass burning. Post emission processes are discussed to provide a context for the emission factor concept within overall atmospheric chemistry and also highlight the potential for rapid changes relative to the scale of some models or remote sensing products. Recent work shows that individual biomass fires emit significantly more gas-phase NMOC than previously thought and that including additional NMOC can improve photochemical model performance. A detailed global estimate suggests that BB emits at least 400 Tg yr^(\u22121) of gas-phase NMOC, which is almost 3 times larger than most previous estimates. Selected recent results (e.g. measurements of HONO and the BB tracers HCN and CH_3CN) are highlighted and key areas requiring future research are briefly discussed.", "date": "2011", "date_type": "published", "publication": "Atmospheric Chemistry and Physics", "volume": "11", "number": "9", "publisher": "European Geosciences Union", "pagerange": "4039-4072", "id_number": "CaltechAUTHORS:20110603-150618670", "issn": "1680-7316", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20110603-150618670", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Paulette Middleton" }, { "agency": "GEIA" }, { "agency": "NSF", "grant_number": "ATM-0513055" }, { "agency": "NSF", "grant_number": "ATM-0936321" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/acp-11-4039-2011", "primary_object": { "basename": "Akagi2011p14035Atmos_Chem_Phys.pdf", "url": "https://authors.library.caltech.edu/records/v2nta-70y56/files/Akagi2011p14035Atmos_Chem_Phys.pdf" }, "related_objects": [ { "basename": "acp-11-4039-2011-supplement.zip", "url": "https://authors.library.caltech.edu/records/v2nta-70y56/files/acp-11-4039-2011-supplement.zip" } ], "resource_type": "article", "pub_year": "2011", "author_list": "Akagi, S. K.; Yokelson, R. J.; et el." }, { "id": "https://authors.library.caltech.edu/records/zpf2p-27159", "eprint_id": 22427, "eprint_status": "archive", "datestamp": "2023-08-19 04:44:06", "lastmod": "2023-10-23 16:01:05", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Froyd-Karl-D", "name": { "family": "Froyd", "given": "K. D." }, "orcid": "0000-0002-0797-6028" }, { "id": "Murphy-Shane-M", "name": { "family": "Murphy", "given": "S. M." }, "orcid": "0000-0002-6415-2607" }, { "id": "Murphy-Daniel-M", "name": { "family": "Murphy", "given": "D. M." }, "orcid": "0000-0002-8091-7235" }, { "id": "de-Gouw-Joost-A", "name": { "family": "de Gouw", "given": "J. A." }, "orcid": "0000-0002-0385-1826" }, { "id": "Eddingsaas-Nathan-C", "name": { "family": "Eddingsaas", "given": "N. C." }, "orcid": "0000-0003-1539-5415" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "Contribution of isoprene-derived organosulfates to free tropospheric aerosol mass", "ispublished": "pub", "full_text_status": "public", "keywords": "acid-catalyzed particle phase reactions epoxides free troposphere secondary organic aerosol", "note": "\u00a9 2010 National Academy of Sciences. \n\nEdited by Mark H. Thiemens, University of California, San Diego, La Jolla, CA, and approved October 21, 2010 (received for review August 24, 2010). Published online before print November 22, 2010. \n\nWe are grateful to Jerome Brioude for FLEXPART analysis of isoprene emissions, to Ann Middlebrook for AMS data from the ITCT/NEAQS 2004 campaign and PALMS data from the 1999 Atlanta Supersite, and to Jason Surratt for valuable input. This work was supported by NOAA base funding, NOAA climate change programs, NASA Earth Science Program Office for aircraft deployments, and the Camille and Henry Dreyfus\nPostdoctoral Program in Environmental Chemistry. S.M. Murphy acknowledges a National Research Council Research Associateship. \n\nAuthor contributions: K.D.F., D.M.M., and P.O.W. designed research; K.D.F., S.M.M., and\nJ.A.d.G. performed research; K.D.F., S.M.M., and J.A.d.G. analyzed data; N.C.E. contributed\nnew reagents/analytic tools; and K.D.F. wrote the paper.\n\nPublished - Froyd2010p12631P_Natl_Acad_Sci_Usa.pdf
Supplemental Material - pnas.1012561107_SI.pdf
", "abstract": "Recent laboratory studies have demonstrated that isoprene oxidation products can partition to atmospheric aerosols by reacting with condensed phase sulfuric acid, forming low-volatility organosulfate compounds. We have identified organosulfate compounds in free tropospheric aerosols by single particle mass spectrometry during several airborne field campaigns. One of these organosulfates is identified as the sulfate ester of IEPOX, a second generation oxidation product of isoprene. The patterns of IEPOX sulfate ester in ambient data generally followed the aerosol acidity and NOx dependence established by laboratory studies. Detection of the IEPOX sulfate ester was most sensitive using reduced ionization laser power, when it was observed in up to 80% of particles in the tropical free troposphere. Based on laboratory mass calibrations, IEPOX added > 0.4% to tropospheric aerosol mass in the remote tropics and up to 20% in regions downwind of isoprene sources. In the southeastern United States, when acidic aerosol was exposed to fresh isoprene emissions, accumulation of IEPOX increased aerosol mass by up to 3%. The IEPOX sulfate ester is therefore one of the most abundant single organic compounds measured in atmospheric aerosol. Our data show that acidity-dependent IEPOX uptake is a mechanism by which anthropogenic SO2 and marine dimethyl sulfide emissions generate secondary biogenic aerosol mass throughout the troposphere.", "date": "2010-12-14", "date_type": "published", "publication": "Proceedings of the National Academy of Sciences of the United States of America", "volume": "107", "number": "50", "publisher": "National Academy of Sciences", "pagerange": "21360-21365", "id_number": "CaltechAUTHORS:20110222-133547224", "issn": "0027-8424", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20110222-133547224", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "National Oceanic and Atmospheric Administration (NOAA)" }, { "agency": "NASA" }, { "agency": "Camille and Henry Dreyfus Foundation" }, { "agency": "National Research Council" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1073/pnas.1012561107", "pmcid": "PMC3003038", "primary_object": { "basename": "Froyd2010p12631P_Natl_Acad_Sci_Usa.pdf", "url": "https://authors.library.caltech.edu/records/zpf2p-27159/files/Froyd2010p12631P_Natl_Acad_Sci_Usa.pdf" }, "related_objects": [ { "basename": "pnas.1012561107_SI.pdf", "url": "https://authors.library.caltech.edu/records/zpf2p-27159/files/pnas.1012561107_SI.pdf" } ], "resource_type": "article", "pub_year": "2010", "author_list": "Froyd, K. D.; Murphy, S. M.; et el." }, { "id": "https://authors.library.caltech.edu/records/axw6t-wda94", "eprint_id": 21102, "eprint_status": "archive", "datestamp": "2023-08-22 01:13:09", "lastmod": "2023-10-20 23:45:57", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Singh-H-B", "name": { "family": "Singh", "given": "H. B." } }, { "id": "Anderson-B-E", "name": { "family": "Anderson", "given": "B. E." } }, { "id": "Brune-W-H", "name": { "family": "Brune", "given": "W. H." }, "orcid": "0000-0002-1609-4051" }, { "id": "Cai-C", "name": { "family": "Cai", "given": "C." } }, { "id": "Cohen-R-C", "name": { "family": "Cohen", "given": "R. C." }, "orcid": "0000-0001-6617-7691" }, { "id": "Crawford-J-H", "name": { "family": "Crawford", "given": "J. H." } }, { "id": "Cubison-M-J", "name": { "family": "Cubison", "given": "M. J." } }, { "id": "Czech-E-P", "name": { "family": "Czech", "given": "E. P." } }, { "id": "Emmons-L", "name": { "family": "Emmons", "given": "L." } }, { "id": "Fuelberg-H-E", "name": { "family": "Fuelberg", "given": "H. E." } }, { "id": "Huey-G-L", "name": { "family": "Huey", "given": "G." } }, { "id": "Jacob-D-J", "name": { "family": "Jacob", "given": "D. J." }, "orcid": "0000-0002-6373-3100" }, { "id": "Jimenez-J-L", "name": { "family": "Jimenez", "given": "J. L." }, "orcid": "0000-0001-6203-1847" }, { "id": "Kaduwela-A", "name": { "family": "Kaduwela", "given": "A." } }, { "id": "Kondo-Y", "name": { "family": "Kondo", "given": "Y." } }, { "id": "Mao-J", "name": { "family": "Mao", "given": "J." } }, { "id": "Olson-J-R", "name": { "family": "Olson", "given": "J. R." } }, { "id": "Sachse-G-W", "name": { "family": "Sachse", "given": "G. W." } }, { "id": "Vay-S-A", "name": { "family": "Vay", "given": "S. A." } }, { "id": "Weinheimer-A-J", "name": { "family": "Weinheimer", "given": "A." }, "orcid": "0000-0001-6175-8286" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Wisthaler-A", "name": { "family": "Wisthaler", "given": "A." } } ] }, "title": "Pollution influences on atmospheric composition and chemistry at high northern latitudes: Boreal and California forest fire emissions", "ispublished": "pub", "full_text_status": "restricted", "keywords": "Arctic pollution; Ozone; Aerosols; Greenhouse gases; Wild fires; Models", "note": "\u00a9 2010 Elsevier Ltd.\n\nReceived 12 April 2010; revised 5 August 2010; accepted 11 August 2010. Available online 21 August 2010.\n\nThe ARCTAS campaign was funded by the NASA Tropospheric\nChemistry Program, the NASA Radiation Sciences Program, and the California Air Resources Board. PTR-MS measurements were supported by the Austrian Research Promotion Agency (FFG), the Tiroler Zukunftstiftung, and the University of Innsbruck. We thank all ARCTAS participants for their contributions.", "abstract": "We analyze detailed atmospheric gas/aerosol composition data acquired during the 2008 NASA ARCTAS (Arctic Research of the Composition of the Troposphere from Aircraft and Satellites) airborne campaign performed at high northern latitudes in spring (ARCTAS-A) and summer (ARCTAS-B) and in California in summer (ARCTAS-CARB). Biomass burning influences were widespread throughout the ARCTAS campaign. MODIS data from 2000 to 2009 indicated that 2008 had the second largest fire counts over Siberia and a more normal Canadian boreal forest fire season. Near surface arctic air in spring contained strong anthropogenic signatures indicated by high sulfate. In both spring and summer most of the pollution plumes transported to the Arctic region were from Europe and Asia and were present in the mid to upper troposphere and contained a mix of forest fire and urban influences. The gas/aerosol composition of the high latitude troposphere was strongly perturbed at all altitudes in both spring and summer. The reactive nitrogen budget was balanced with PAN as the dominant component. Mean ozone concentrations in the high latitude troposphere were only minimally perturbed (<5 ppb), although many individual pollution plumes sampled in the mid to upper troposphere, and mixed with urban influences, contained elevated ozone (\u0394O_3/\u0394CO = 0.11 \u00b1 0.09 v/v). Emission and optical characteristics of boreal and California wild fires were quantified and found to be broadly comparable. Greenhouse gas emission estimates derived from ARCTAS-CARB data for the South Coast Air Basin of California show good agreement with state inventories for CO_2 and N_(2)O but indicate substantially larger emissions of CH_4. Simulations by multiple models of transport and chemistry were found to be broadly consistent with observations with a tendency towards under prediction at high latitudes.", "date": "2010-11", "date_type": "published", "publication": "Atmospheric Environment", "volume": "44", "number": "36", "publisher": "Elsevier", "pagerange": "4553-4564", "id_number": "CaltechAUTHORS:20101201-135740587", "issn": "1352-2310", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20101201-135740587", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA" }, { "agency": "California Air Resources Board" }, { "agency": "Austrian Research Promotion Agency (FFG)" }, { "agency": "Tiroler Zukunftstiftung" }, { "agency": "University of Innsbruck" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "corp_creators": { "items": [ "ARCTAS Science Team" ] }, "doi": "10.1016/j.atmosenv.2010.08.026", "resource_type": "article", "pub_year": "2010", "author_list": "Singh, H. B.; Anderson, B. E.; et el." }, { "id": "https://authors.library.caltech.edu/records/800f7-qdy62", "eprint_id": 21227, "eprint_status": "archive", "datestamp": "2023-08-22 01:08:44", "lastmod": "2023-10-20 23:51:50", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Alvarado-M-J", "name": { "family": "Alvarado", "given": "M. J." } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Kurten-A", "name": { "family": "Kurten", "given": "A." } }, { "id": "Crounse-J-D", "name": { "family": "Crounse", "given": "J." }, "orcid": "0000-0001-5443-729X" }, { "id": "St-Clair-J-M", "name": { "family": "St. Clair", "given": "J. M." }, "orcid": "0000-0002-9367-5749" } ] }, "title": "Nitrogen oxides and PAN in plumes from boreal fires during ARCTAS-B and their impact on ozone: an integrated analysis of aircraft and satellite observations", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 Author(s) 2010. 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: 8 June 2010 \u2013 Published in Atmos. Chem. Phys. Discuss.: 22 June 2010.\nRevised: 7 October 2010 \u2013 Accepted: 8 October 2010 \u2013 Published: 18 October 2010.\n\n\nWe thank all of the members of the ARCTAS\nScience Team and the TES Science Team for their work. We\nthank D. J. Jacob, J. A. Fisher, and Q. Wang of Harvard and the\nanonymous reviewers for their helpful comments. This research\nwas supported by NASA grant NNX09AC51G to Harvard University\n(MJA and JAL) and NASA grant NBNX08AD39G to the\nUniversity of Colorado (MJC and JLJ). PTR-MS measurements\nwere supported by the Austrian Research Promotion Agency\n(FFG), the Tiroler Zukunftstiftung and the research groups led by\nA. Hansel and T. D. M\u00e4rk.\nEdited by: P. Monks.\n\nPublished - Alvarado2010p12045Atmos_Chem_Phys.pdf
", "abstract": "We determine enhancement ratios for NO_x, PAN, and other NO_y species from boreal biomass burning using aircraft data obtained during the ARCTAS-B campaign and examine the impact of these emissions on tropospheric ozone in the Arctic. We find an initial emission factor for NO_x of 1.06 g NO per kg dry matter (DM) burned, much lower than previous observations of boreal plumes, and also one third the value recommended for extratropical fires. Our analysis provides the first observational confirmation of rapid PAN formation in a boreal smoke plume, with 40% of the initial NO_x emissions being converted to PAN in the first few hours after emission. We find little clear evidence for ozone formation in the boreal smoke plumes during ARCTAS-B in either aircraft or satellite observations, or in model simulations. Only a third of the smoke plumes observed by the NASA DC8 showed a correlation between ozone and CO, and ozone was depleted in the plumes as often as it was enhanced. Special observations from the Tropospheric Emission Spectrometer (TES) also show little evidence for enhanced ozone in boreal smoke plumes between 15 June and 15 July 2008. Of the 22 plumes observed by TES, only 4 showed ozone increasing within the smoke plumes, and even in those cases it was unclear that the increase was caused by fire emissions. Using the GEOS-Chem atmospheric chemistry model, we show that boreal fires during ARCTAS-B had little impact on the median ozone profile measured over Canada, and had little impact on ozone within the smoke plumes observed by TES.", "date": "2010-10-18", "date_type": "published", "publication": "Atmospheric Chemistry and Physics", "volume": "10", "number": "20", "publisher": "European Geosciences Union", "pagerange": "9739-9760", "id_number": "CaltechAUTHORS:20101208-081314363", "issn": "1680-7316", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20101208-081314363", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NNX09AC51G" }, { "agency": "NASA", "grant_number": "NBNX08AD39G" }, { "agency": "Austrian Research Promotion Agency (FFG)" }, { "agency": "Tiroler Zukunftstiftung" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/acp-10-9739-2010", "primary_object": { "basename": "Alvarado2010p12045Atmos_Chem_Phys.pdf", "url": "https://authors.library.caltech.edu/records/800f7-qdy62/files/Alvarado2010p12045Atmos_Chem_Phys.pdf" }, "resource_type": "article", "pub_year": "2010", "author_list": "Alvarado, M. J.; Wennberg, P. O.; et el." }, { "id": "https://authors.library.caltech.edu/records/f2zgs-wmc98", "eprint_id": 47257, "eprint_status": "archive", "datestamp": "2023-08-22 01:06:20", "lastmod": "2023-10-26 20:26:48", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Wunch-D", "name": { "family": "Wunch", "given": "D." }, "orcid": "0000-0002-4924-0377" }, { "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": "Blavier-J-F-L", "name": { "family": "Blavier", "given": "J.-F. L." } }, { "id": "Keppel-Aleks-G", "name": { "family": "Keppel-Aleks", "given": "G." } }, { "id": "Roehl-C-M", "name": { "family": "Roehl", "given": "C. M." }, "orcid": "0000-0001-5383-8462" } ] }, "title": "Calibration of the Total Carbon Column Observing Network using aircraft profile data", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2010 Author(s). \nThis work is distributed\nunder the Creative Commons Attribution 3.0 License. \nPublished by Copernicus Publications on behalf of the European Geosciences Union. \n\nReceived: 27 May 2010. Published in Atmos. Meas. Tech. Discuss.: 17 June 2010\nRevised: 16 September 2010. Accepted: 17 September 2010. Published: 6 October 2010. \n\nThe authors wish to thank Stephanie Vay and Donald R. Blake for guidance and the use\nof the INTEX-NA CO2 and CH4 profiles, respectively. The INTEX-NA data were downloaded from ftp://ftp-air.larc.nasa.gov/pub/INTEXA/DC8 AIRCRAFT/ on 10 September 2010. NCEP Reanalysis data is provided by the NOAA/OAR/ESRL PSD, Boulder, Colorado, USA, from their Web site at http://www.cdc.noaa.gov/. Data were obtained through the\nAtmospheric Radiation Measurement (ARM) Program sponsored\nby the US Department of Energy, Office of Science, Office of Biological and Environmental Research. Data were generated by the National Oceanic and Atmospheric Administration (NOAA), Earth System Research Laboratory (ESRL), Carbon Cycle Greenhouse Gases Group, including flask data from Andrews et al. (2009). The Meteorological Research Institute tower measurements are described by Inoue and Matsueda (1996). US funding for TCCON comes from NASA's Terrestrial Ecology Program, the Orbiting\nCarbon Observatory project and the DOE/ARM Program. Part\nof this work was performed at the Jet Propulsion Laboratory,\nCalifornia Institute of Technology, under contract with NASA. ACE is funded primarily by the Canadian Space Agency. Support for the Learjet-25 measurements was provided by the NASA ASCENDS development and ESTO IIP programs. Support for\nthe flask measurements at the SGP ARM site is from LBNL-DOE\ncontract DE-AC02-05CH11231. We acknowledge funding for\nDarwin and Wollongong from the Australian Research Council,\nProjects DP0879468 and LP0562346 with the Australian Greenhouse Office. The National Center for Atmospheric Research is sponsored by the National Science Foundation.\nEdited by: H. Worden.\n\nPublished - amt-3-1351-2010.pdf
", "abstract": "The Total Carbon Column Observing Network (TCCON) produces precise measurements of the column average dry-air mole fractions of CO_2, CO, CH_4, N_2O and H_2O at a variety of sites worldwide. These observations rely on spectroscopic parameters that are not known with sufficient accuracy to compute total columns that can be used in combination with in situ measurements. The TCCON must therefore be calibrated to World Meteorological Organization (WMO) in situ trace gas measurement scales. We present a calibration of TCCON data using WMO-scale instrumentation aboard aircraft that measured profiles over four TCCON stations during 2008 and 2009. These calibrations are compared with similar observations made in 2004 and 2006. The results indicate that a single, global calibration factor for each gas accurately captures the TCCON total column data within error.", "date": "2010-10-06", "date_type": "published", "publication": "Atmospheric Measurement Techniques", "volume": "3", "number": "5", "publisher": "European Geosciences Union", "pagerange": "1351-1362", "id_number": "CaltechAUTHORS:20140716-090557341", "issn": "1867-1381", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140716-090557341", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)" }, { "agency": "NASA/JPL/Caltech" }, { "agency": "Canadian Space Agency (CSA)" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" }, { "agency": "Australian Research Council", "grant_number": "DP0879468" }, { "agency": "Australian Research Council", "grant_number": "LP0562346" }, { "agency": "Australian Greenhouse Office" }, { "agency": "NSF" }, { "agency": "Lawrence Berkeley National Laboratory" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/amt-3-1351-2010", "primary_object": { "basename": "amt-3-1351-2010.pdf", "url": "https://authors.library.caltech.edu/records/f2zgs-wmc98/files/amt-3-1351-2010.pdf" }, "resource_type": "article", "pub_year": "2010", "author_list": "Wunch, D.; Toon, G. C.; et el." }, { "id": "https://authors.library.caltech.edu/records/ygptx-1z603", "eprint_id": 20515, "eprint_status": "archive", "datestamp": "2023-08-22 00:42:34", "lastmod": "2023-10-20 23:08:29", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "St-Clair-J-M", "name": { "family": "St. Clair", "given": "Jason M." }, "orcid": "0000-0002-9367-5749" }, { "id": "McCabe-D-C", "name": { "family": "McCabe", "given": "David C." } }, { "id": "Crounse-J-D", "name": { "family": "Crounse", "given": "John D." }, "orcid": "0000-0001-5443-729X" }, { "id": "Steiner-U", "name": { "family": "Steiner", "given": "Urs" } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "Chemical ionization tandem mass spectrometer for the in situ measurement of methyl hydrogen peroxide", "ispublished": "pub", "full_text_status": "public", "keywords": "ionisation; mass spectrometers", "note": "\u00a9 2010 American Institute of Physics. \n\nReceived 6 April 2010; accepted 27 July 2010; published online 22 September 2010. \n\nWe thank James Oliver for support with mechanical designs\nused for the fabrication of custom parts in this instrument\nas well as parts needed for integration onto the aircraft\nand Norton Allen for support with the QNX-based control/\ndata-collection software. We also thank NCAR/NSF C-130\nand NASA DC-8 aircraft crew, pilots, and engineers and\nsupport staff for assistance with integration of instrumentation\nonto aircraft and for successful completion of science\nmissions. Funding for this research was provided by the\nNASA Tropospheric Chemistry Program. This instrument\nwould have not been possible without the financial\nsupport of Caltech trustee William Davidow. J.D.C. acknowledges\nEPA-STAR Fellowship Program (Contract No.\nFP916334012) support. This work has not been formally reviewed\nby the EPA. The views expressed in this document\nare solely those of the authors and the EPA does not endorse\nany products or commercial services mentioned in this publication.\n\nPublished - StClair2010p11618Review_of_Scientific_Instruments.pdf
", "abstract": "A new approach for measuring gas-phase methyl hydrogen peroxide [(MHP) CH_3OOH] utilizing chemical ionization mass spectrometry is presented. Tandem mass spectrometry is used to avoid mass interferences that hindered previous attempts to measure atmospheric CH_3OOH with CF_3O\u2212 clustering chemistry. CH_3OOH has been successfully measured in situ using this technique during both airborne and ground-based campaigns. The accuracy and precision for the MHP measurement are a function of water vapor mixing ratio. Typical precision at 500 pptv MHP and 100 ppmv H_2O is \u00b180 pptv (2 sigma) for a 1 s integration period. The accuracy at 100 ppmv H_2O is estimated to be better than \u00b140%. Chemical ionization tandem mass spectrometry shows considerable promise for the determination of in situ atmospheric trace gas mixing ratios where isobaric compounds or mass interferences impede accurate measurements.", "date": "2010-09", "date_type": "published", "publication": "Review of Scientific Instruments", "volume": "81", "number": "9", "publisher": "American Institute of Physics", "pagerange": "Art. No. 094102", "id_number": "CaltechAUTHORS:20101025-142235804", "issn": "0034-6748", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20101025-142235804", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA" }, { "agency": "Caltech" }, { "agency": "Environmental Protection Agency (EPA)", "grant_number": "FP916334012" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1063/1.3480552", "primary_object": { "basename": "StClair2010p11618Review_of_Scientific_Instruments.pdf", "url": "https://authors.library.caltech.edu/records/ygptx-1z603/files/StClair2010p11618Review_of_Scientific_Instruments.pdf" }, "resource_type": "article", "pub_year": "2010", "author_list": "St. Clair, Jason M.; McCabe, David C.; et el." }, { "id": "https://authors.library.caltech.edu/records/bz10r-hmt53", "eprint_id": 19586, "eprint_status": "archive", "datestamp": "2023-08-19 03:32:03", "lastmod": "2023-10-20 21:10:33", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Eddingsaas-Nathan-C", "name": { "family": "Eddingsaas", "given": "Nathan C." }, "orcid": "0000-0003-1539-5415" }, { "id": "VanderVelde-D-G", "name": { "family": "VanderVelde", "given": "David G." }, "orcid": "0000-0002-2907-0366" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "Kinetics and Products of the Acid-Catalyzed Ring-Opening of Atmospherically Relevant Butyl Epoxy Alcohols", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2010 American Chemical Society. \n\nReceived: April 29, 2010; Revised Manuscript Received: June 22, 2010. Publication Date (Web): July 21, 2010. \n\nN. C. E. was supported by the Camille and Henry Dreyfus Postdoctoral Program in Environmental Chemistry. We also thank ManNin Chan, Fabien Paulot, Havala Pye, and Jason Surratt for helpful discussions.\n\nSupplemental Material - jp103907c_si_001.pdf
", "abstract": "Epoxydiols are produced in the gas phase from the photo-oxidation of isoprene in the absence of significant mixing ratios of nitrogen oxides (NO\u2093). The reactive uptake of these compounds onto acidic aerosols has been shown to produce secondary organic aerosol (SOA). To better characterize the fate of isoprene epoxydiols in the aerosol phase, the kinetics and products of the acid-catalyzed ring-opening reactions of four hydroxy-substituted epoxides were studied by nuclear magnetic resonance (NMR) techniques. Polyols and sulfate esters are observed from the ring-opening of the epoxides in solutions of H\u2082SO\u2084/Na\u2082SO\u2084. Likewise, polyols and nitrate esters are produced in solutions of HNO\u2083/NaNO\u2083. In sulfuric acid, the rate of acid-catalyzed ring-opening is dependent on hydronium ion activity, sulfate ion, and bisulfate. The rates are much slower than the nonhydroxylated equivalent epoxides; however, the hydroxyl groups make them much more water-soluble. A model was constructed with the major channels for epoxydiol loss (i.e., aerosol-phase ring-opening, gas-phase oxidation, and deposition). In the atmosphere, SOA formation from epoxydiols will depend on a number of variables (e.g., pH and aerosol water content) with the yield of ring-opening products varying from less than 1% to greater than 50%.", "date": "2010-08-12", "date_type": "published", "publication": "Journal of Physical Chemistry A", "volume": "114", "number": "31", "publisher": "American Chemical Society", "pagerange": "8106-8113", "id_number": "CaltechAUTHORS:20100823-101349556", "issn": "1089-5639", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20100823-101349556", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Camille and Henry Dreyfus Foundation" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1021/jp103907c", "primary_object": { "basename": "jp103907c_si_001.pdf", "url": "https://authors.library.caltech.edu/records/bz10r-hmt53/files/jp103907c_si_001.pdf" }, "resource_type": "article", "pub_year": "2010", "author_list": "Eddingsaas, Nathan C.; VanderVelde, David G.; et el." }, { "id": "https://authors.library.caltech.edu/records/xkn2x-xst56", "eprint_id": 19967, "eprint_status": "archive", "datestamp": "2023-08-22 00:32:27", "lastmod": "2023-10-20 22:05:13", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Voss-P-B", "name": { "family": "Voss", "given": "P. B." } }, { "id": "Zaveri-R-A", "name": { "family": "Zaveri", "given": "R. A." }, "orcid": "0000-0001-9874-8807" }, { "id": "Flocke-F-M", "name": { "family": "Flocke", "given": "F. M." } }, { "id": "Mao-H", "name": { "family": "Mao", "given": "H." } }, { "id": "Hartley-T-P", "name": { "family": "Hartley", "given": "T. P." } }, { "id": "DeAmicis-P", "name": { "family": "DeAmicis", "given": "P." } }, { "id": "Deonandan-I", "name": { "family": "Deonandan", "given": "I." } }, { "id": "Contreras-Jim\u00e9nez-G", "name": { "family": "Contreras-Jim\u00e9nez", "given": "G." } }, { "id": "Mart\u00ednez-Antonio-O", "name": { "family": "Mart\u00ednez-Antonio", "given": "O." } }, { "id": "Figueroa-Estrada-M", "name": { "family": "Figueroa Estrada", "given": "M." } }, { "id": "Greenberg-D", "name": { "family": "Greenberg", "given": "D." } }, { "id": "Campos-T-L", "name": { "family": "Campos", "given": "T. L." } }, { "id": "Weinheimer-A-J", "name": { "family": "Weinheimer", "given": "A. J." }, "orcid": "0000-0001-6175-8286" }, { "id": "Knapp-D-J", "name": { "family": "Knapp", "given": "D. J." } }, { "id": "Montzka-D-D", "name": { "family": "Montzka", "given": "D. D." } }, { "id": "Crounse-J-D", "name": { "family": "Crounse", "given": "J. D." }, "orcid": "0000-0001-5443-729X" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Apel-E", "name": { "family": "Apel", "given": "E." } }, { "id": "Madronich-S", "name": { "family": "Madronich", "given": "S." } }, { "id": "de-Foy-B", "name": { "family": "de Foy", "given": "B." } } ] }, "title": "Long-range pollution transport during the MILAGRO-2006 campaign: a case study of a major Mexico City outflow event using free-floating altitude-controlled balloons", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 Author(s) 2010. This work is distributed under the Creative Commons Attribution 3.0 License.\n\nReceived: 22 January 2010; Published in Atmos. Chem. Phys. Discuss.: 9 February 2010. Revised: 28 June 2010; Accepted: 16 July 2010; Published: 4 August 2010.\n\nWe gratefully acknowledge the support of\nthe National Science Foundation Atmospheric Chemistry Program\n(Grant Numbers: ATM-0511833, ATM-0810950, and ATM-\n0511803), the National Center for Atmospheric Research (NCAR),\nthe Servicios a la Navegac\u00edon en el Espacio A\u00e9reo Mexicano\n(SENEAM), Instituto Nacional de Ecolog\u00eda (INE), pilots and crew\nof the C-130, Jos\u00e9 Meit\u00edn at NCAR, Sandra I. Ram\u00edrez Jim\u00e9nez\nat the Centro de Ciencias de la Atm\u00f3sfera, Universidad Nacional\nAut\u00f3noma de M\u00e9xico, and our many gracious hosts in Mexico.\nThe C-130 meteorological data and SABL imagery was provided\nby NCAR/EOL under sponsorship of the National Science\nFoundation. All analysis was performed in the Matlab (v7.0.1)\nprogramming environment from the MathWorks Inc.\nEdited by: L. Molina.\n\nPublished - Voss2010p11324Atmos_Chem_Phys.pdf
", "abstract": "One of the major objectives of the Megacities Initiative: Local And Global Research Observations (MILAGRO-2006) campaign was to investigate the long-range transport of polluted Mexico City Metropolitan Area (MCMA) outflow and determine its downwind impacts on air quality and climate. Six research aircraft, including the National Center for Atmospheric Research (NCAR) C-130, made extensive chemical, aerosol, and radiation measurements above MCMA and more than 1000 km downwind in order to characterize the evolution of the outflow as it aged and dispersed over the Mesa Alta, Sierra Madre Oriental, Coastal Plain, and Gulf of Mexico. As part of this effort, free-floating Controlled-Meteorological (CMET) balloons, commanded to change altitude via satellite, made repeated profile measurements of winds and state variables within the advecting outflow. In this paper, we present an analysis of the data from two CMET balloons that were launched near Mexico City on the afternoon of 18 March 2006 and floated downwind with the MCMA pollution for nearly 30 h. The repeating profile measurements show the evolving structure of the outflow in considerable detail: its stability and stratification, interaction with other air masses, mixing episodes, and dispersion into the regional background. Air parcel trajectories, computed directly from the balloon wind profiles, show three transport pathways on 18\u201319 March: (a) high-altitude advection of the top of the MCMA mixed layer, (b) mid-level outflow over the Sierra Madre Oriental followed by decoupling and isolated transport over the Gulf of Mexico, and (c) low-level outflow with entrainment into a cleaner northwesterly jet above the Coastal Plain. The C-130 aircraft intercepted the balloon-based trajectories three times on 19 March, once along each of these pathways; in all three cases, peaks in urban tracer concentrations and LIDAR backscatter are consistent with MCMA pollution. In comparison with the transport models used in the campaign, the balloon-based trajectories appear to shear the outflow far more uniformly and decouple it from the surface, thus forming a thin but expansive polluted layer over the Gulf of Mexico that is well aligned with the aircraft observations. These results provide critical context for the extensive aircraft measurements made during the 18\u201319 March MCMA outflow event and may have broader implications for modelling and understanding long-range transport.", "date": "2010-08-04", "date_type": "published", "publication": "Atmospheric Chemistry and Physics", "volume": "10", "number": "15", "publisher": "European Geosciences Union", "pagerange": "7137-7159", "id_number": "CaltechAUTHORS:20100915-094034098", "issn": "1680-7316", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20100915-094034098", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "ATM-0511833" }, { "agency": "NSF", "grant_number": "ATM-0810950" }, { "agency": "NSF", "grant_number": "ATM- 0511803" }, { "agency": "National Center for Atmospheric Research (NCAR)" }, { "agency": "Servicios a la Navegaci\u00f3n en el Espacio A\u00e9reo Mexicano (SENEAM)" }, { "agency": "Instituto Nacional de Ecolog\u00eda (INE)" }, { "agency": "Universidad Nacional Aut\u00f3noma de M\u00e9xico (UNAM)" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/acp-10-7137-2010", "primary_object": { "basename": "Voss2010p11324Atmos_Chem_Phys.pdf", "url": "https://authors.library.caltech.edu/records/xkn2x-xst56/files/Voss2010p11324Atmos_Chem_Phys.pdf" }, "resource_type": "article", "pub_year": "2010", "author_list": "Voss, P. B.; Zaveri, R. A.; et el." }, { "id": "https://authors.library.caltech.edu/records/pdk4n-mep40", "eprint_id": 19974, "eprint_status": "archive", "datestamp": "2023-08-19 03:27:20", "lastmod": "2023-10-20 22:05:30", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Chan-Arthur-W-H", "name": { "family": "Chan", "given": "A. W. H." }, "orcid": "0000-0001-7392-4237" }, { "id": "Chan-Man-Nin", "name": { "family": "Chan", "given": "M. N." }, "orcid": "0000-0002-2384-2695" }, { "id": "Surratt-Jason-D", "name": { "family": "Surratt", "given": "J. D." }, "orcid": "0000-0002-6833-1450" }, { "id": "Chhabra-Puneet-S", "name": { "family": "Chhabra", "given": "P. S." } }, { "id": "Loza-Christine-L", "name": { "family": "Loza", "given": "C. L." } }, { "id": "Crounse-John-D", "name": { "family": "Crounse", "given": "J. D." }, "orcid": "0000-0001-5443-729X" }, { "id": "Yee-Lindsay-D", "name": { "family": "Yee", "given": "L. D." }, "orcid": "0000-0001-8965-9319" }, { "id": "Flagan-R-C", "name": { "family": "Flagan", "given": "R. C." }, "orcid": "0000-0001-5690-770X" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Seinfeld-J-H", "name": { "family": "Seinfeld", "given": "J. H." }, "orcid": "0000-0003-1344-4068" } ] }, "title": "Role of aldehyde chemistry and NO_x concentrations in secondary organic aerosol formation", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 Author(s) 2010. This work is distributed\nunder the Creative Commons Attribution 3.0 License.\nReceived: 7 April 2010 \u2013 Published in Atmos. Chem. Phys. Discuss.: 19 April 2010.\nRevised: 13 July 2010 \u2013 Accepted: 16 July 2010 \u2013 Published: 4 August 2010.\n\nThis research was funded by US Department\nof Energy Biological and Environmental Research Program\nDE-FG02-05ER63983, US Environmental Protection Agency\nSTAR grant RD-83374901, US National Science Foundation grant\nATM-0432377, and the Electric Power Research Institute. This\npublication has not been formally reviewed by the EPA. The views\nexpressed in this document are solely those of the authors and EPA\ndoes not endorse any products mentioned in this publication. The\nauthors would like to thank K. E. Kautzman and A. J. Kwan for\nexperimental assistance, and F. Paulot for helpful discussion.\nEdited by: M. Gysel.\n\nPublished - Chan2010p11330Atmos_Chem_Phys.pdf
Supplemental Material - acp-10-7169-2010-supplement_1_.pdf
", "abstract": "Aldehydes are an important class of products from atmospheric oxidation of hydrocarbons. Isoprene (2-methyl-1,3-butadiene), the most abundantly emitted atmospheric non-methane hydrocarbon, produces a significant amount of secondary organic aerosol (SOA) via methacrolein (a C_4-unsaturated aldehyde) under urban high-NO_x conditions. Previously, we have identified peroxy methacryloyl nitrate (MPAN) as the important intermediate to isoprene and methacrolein SOA in this NO_x regime. Here we show that as a result of this chemistry, NO_2 enhances SOA formation from methacrolein and two other \u03b1, \u03b2-unsaturated aldehydes, specifically acrolein and crotonaldehyde, a NO_x effect on SOA formation previously unrecognized. Oligoesters of dihydroxycarboxylic acids and hydroxynitrooxycarboxylic acids are observed to increase with increasing NO_2/NO ratio, and previous characterizations are confirmed by both online and offline high-resolution mass spectrometry techniques. Molecular structure also determines the amount of SOA formation, as the SOA mass yields are the highest for aldehydes that are \u03b1, \u03b2-unsaturated and contain an additional methyl group on the \u03b1-carbon. Aerosol formation from 2-methyl-3-buten-2-ol (MBO232) is insignificant, even under high-NO_2 conditions, as PAN (peroxy acyl nitrate, RC(O)OONO_2) formation is structurally unfavorable. At atmospherically relevant NO_2/NO ratios (3\u20138), the SOA yields from isoprene high-NO_x photooxidation are 3 times greater than previously measured at lower NO_2/NO ratios. At sufficiently high NO_2 concentrations, in systems of \u03b1, \u03b2-unsaturated aldehydes, SOA formation from subsequent oxidation of products from acyl peroxyl radicals+NO_2 can exceed that from RO_2+HO_2 reactions under the same inorganic seed conditions, making RO_2+NO_2 an important channel for SOA formation.", "date": "2010-08-04", "date_type": "published", "publication": "Atmospheric Chemistry and Physics", "volume": "10", "number": "15", "publisher": "European Geosciences Union", "pagerange": "7169-7188", "id_number": "CaltechAUTHORS:20100915-133230350", "issn": "1680-7316", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20100915-133230350", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-FG02-05ER63983" }, { "agency": "Environmental Protection Agency (EPA)", "grant_number": "RD-83374901" }, { "agency": "NSF", "grant_number": "ATM-0432377" }, { "agency": "Electric Power Research Institute (EPRI)" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/acp-10-7169-2010", "primary_object": { "basename": "Chan2010p11330Atmos_Chem_Phys.pdf", "url": "https://authors.library.caltech.edu/records/pdk4n-mep40/files/Chan2010p11330Atmos_Chem_Phys.pdf" }, "related_objects": [ { "basename": "acp-10-7169-2010-supplement_1_.pdf", "url": "https://authors.library.caltech.edu/records/pdk4n-mep40/files/acp-10-7169-2010-supplement_1_.pdf" } ], "resource_type": "article", "pub_year": "2010", "author_list": "Chan, A. W. H.; Chan, M. N.; et el." }, { "id": "https://authors.library.caltech.edu/records/6nz98-m2b58", "eprint_id": 20078, "eprint_status": "archive", "datestamp": "2023-08-23 23:32:58", "lastmod": "2023-10-20 22:12:21", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Deutscher-N-M", "name": { "family": "Deutscher", "given": "N. M." }, "orcid": "0000-0002-2906-2577" }, { "id": "Griffith-D-W-T", "name": { "family": "Griffith", "given": "D. W. T." }, "orcid": "0000-0002-7986-1924" }, { "id": "Bryant-G-W", "name": { "family": "Bryant", "given": "G. W." } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Toon-G-C", "name": { "family": "Toon", "given": "G. C." }, "orcid": "0000-0003-4174-7541" }, { "id": "Washenfelder-R-A", "name": { "family": "Washenfelder", "given": "R. A." }, "orcid": "0000-0002-8106-3702" }, { "id": "Keppel-Aleks-G", "name": { "family": "Keppel-Aleks", "given": "G." } }, { "id": "Wunch-D", "name": { "family": "Wunch", "given": "D." }, "orcid": "0000-0002-4924-0377" }, { "id": "Yavin-Y", "name": { "family": "Yavin", "given": "Y." } }, { "id": "Allen-N-T", "name": { "family": "Allen", "given": "N. T." } }, { "id": "Blavier-J-F-L", "name": { "family": "Blavier", "given": "J.-F." } }, { "id": "Jim\u00e9nez-R", "name": { "family": "Jim\u00e9nez", "given": "R." } }, { "id": "Daube-B-C-Jr", "name": { "family": "Daube", "given": "B. C." } }, { "id": "Bright-A-V", "name": { "family": "Bright", "given": "A. V." } }, { "id": "Matross-D-M", "name": { "family": "Matross", "given": "D. M." } }, { "id": "Wofsy-S-C", "name": { "family": "Wofsy", "given": "S. C." }, "orcid": "0000-0002-3990-6737" }, { "id": "Park-S", "name": { "family": "Park", "given": "S." } } ] }, "title": "Total column CO_2 measurements at Darwin, Australia \u2013 site description and calibration against in situ aircraft profiles", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 Author(s) 2010. This work is distributed\nunder the Creative Commons Attribution 3.0 License.\n\nReceived: 3 March 2010; Published in Atmos. Meas. Tech. Discuss.: 17 March 2010; Revised: 26 May 2010; Accepted: 7 July 201; Published: 19 July 2010.\n\nWe thank Rex Pearson, John Glowacki, Troy Culgan, Maciej Ryczek and Krzysztof Krzton for the maintenance of the solar FTS. We also gratefully acknowledge comments on the\nmanuscript made by Janina Messerschmidt. Nicholas Deutscher\nis supported by an Australian Postgraduate Industry Award. The research described in this paper was performed for the Orbiting Carbon Observatory Project at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration. TCCON is funded by the NASA terrestrial carbon cycle program, grant NNX08AI86G. This research is also assisted by Australian Research Council Projects\nDP0879468 and LP0562346 with the Australian Greenhouse\nOffice.\nEdited by: I. Aben\n\nPublished - Deutscher2010p11398Atmos_Meas_Tech.pdf
", "abstract": "An automated Fourier Transform Spectroscopic (FTS) solar observatory was established in Darwin, Australia in August 2005. The laboratory is part of the Total Carbon Column Observing Network, and measures atmospheric column abundances of CO_2 and O_2 and other gases. Measured CO_2 columns were calibrated against integrated aircraft profiles obtained during the TWP-ICE campaign in January\u2013February 2006, and show good agreement with calibrations for a similar instrument in Park Falls, Wisconsin. A clear-sky low airmass relative precision of 0.1% is demonstrated in the CO2 and O2 retrieved column-averaged volume mixing ratios. The 1% negative bias in the FTS X_(CO_2) relative to the World Meteorological Organization (WMO) calibrated in situ scale is within the uncertainties of the NIR spectroscopy and analysis.", "date": "2010-07-19", "date_type": "published", "publication": "Atmospheric Measurement Techniques", "volume": "3", "number": "4", "publisher": "European Geosciences Union", "pagerange": "947-958", "id_number": "CaltechAUTHORS:20100921-152009827", "issn": "1867-1381", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20100921-152009827", "rights": "This work is distributed under the Creative Commons Attribution 3.0 License.", "funders": { "items": [ { "agency": "Australian Postgraduate Industry Award" }, { "agency": "NASA", "grant_number": "NNX08AI86G" }, { "agency": "Australian Research Council", "grant_number": "DP0879468" }, { "agency": "Australian Research Council", "grant_number": "LP0562346" }, { "agency": "Australian Greenhouse Office" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/amt-3-947-2010", "primary_object": { "basename": "Deutscher2010p11398Atmos_Meas_Tech.pdf", "url": "https://authors.library.caltech.edu/records/6nz98-m2b58/files/Deutscher2010p11398Atmos_Meas_Tech.pdf" }, "resource_type": "article", "pub_year": "2010", "author_list": "Deutscher, N. M.; Griffith, D. W. T.; et el." }, { "id": "https://authors.library.caltech.edu/records/bntxk-tpj36", "eprint_id": 19358, "eprint_status": "archive", "datestamp": "2023-08-23 23:32:09", "lastmod": "2023-10-20 20:36:33", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Toon-O-B", "name": { "family": "Toon", "given": "Owen B." } }, { "id": "Starr-D-O", "name": { "family": "Starr", "given": "David O." } }, { "id": "Jensen-E-J", "name": { "family": "Jensen", "given": "Eric J." } }, { "id": "Newman-P-A", "name": { "family": "Newman", "given": "Paul A." } }, { "id": "Platnick-S", "name": { "family": "Platnick", "given": "Steven" } }, { "id": "Schoeberl-M-R", "name": { "family": "Schoeberl", "given": "Mark R." } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Wofsy-S-C", "name": { "family": "Wofsy", "given": "Steven C." }, "orcid": "0000-0002-3990-6737" }, { "id": "Kurylo-M-J", "name": { "family": "Kurylo", "given": "Michael J." } }, { "id": "Maring-H", "name": { "family": "Maring", "given": "Hal" } }, { "id": "Jucks-K-W", "name": { "family": "Jucks", "given": "Kenneth W." } }, { "id": "Craig-M-S", "name": { "family": "Craig", "given": "Michael S." } }, { "id": "Vasques-M-F", "name": { "family": "Vasques", "given": "Marilyn F." } }, { "id": "Pfister-L", "name": { "family": "Pfister", "given": "Lenny" } }, { "id": "Rosenlof-K-H", "name": { "family": "Rosenlof", "given": "Karen H." } }, { "id": "Selkirk-H-B", "name": { "family": "Selkirk", "given": "Henry B." } }, { "id": "Colarco-P-R", "name": { "family": "Colarco", "given": "Peter R." } }, { "id": "Kawa-S-R", "name": { "family": "Kawa", "given": "Stephan R." } }, { "id": "Mace-G-G", "name": { "family": "Mace", "given": "Gerald G." } }, { "id": "Minnis-P", "name": { "family": "Minnis", "given": "Patrick" } }, { "id": "Pickering-K-E", "name": { "family": "Pickering", "given": "Kenneth E." } } ] }, "title": "Planning, implementation, and first results of the Tropical Composition, Cloud and Climate Coupling Experiment (TC4)", "ispublished": "pub", "full_text_status": "public", "keywords": "clouds; chemistry; experiment", "note": "\u00a9 2010 American Geophysical Union.\n\nReceived 24 August 2009; accepted 2 March 2010; published 15 July 2010. \n\nThe TC4 mission was supported by the\nAtmospheric Composition research area of NASA's Earth Science Division.\nWe thank the aircraft managers, engineers, and ground crews of all the aircraft\nthat participated in TC4. We particularly thank the pilots of the ER\u20102,\nDavid Wright, Denis Steele, and DeLewis Porter, and Mobile Pilot Jan\nNystrom, the WB\u201057F pilots Rob Rivers, Scott Reagan, and William\nRieke, and Backseaters, John Bain, Dominic Del Russo, and Joseph Gerky,\nand the DC\u20108 pilots William Brocket, Mike Fuller, Manny Puerta, and the\nlate Edwin Lewis. The ER\u20102 aircraft and pilots were very well supported\nby the personnel of NASA's Dryden Flight Research Center Airborne Science\nDirectorate, the WB\u201057F by NASA's Johnson Space Center High\nAltitude Research Program, and the DC\u20108 by the University of North\nDakota's National Science Education Research Center. We thank the\nER\u20102 Aircraft Program Director, Robert Curry, the DC\u20108 Program Director,\nRick Shetter, and the WB\u201057F Program Manager, Ken Cockrell. We also\nthank the ER\u20102 aircraft coordinators Jacques Vachon and Mike Kapitzke,\nthe DC\u20108 Aircraft Manager Steve Davis and the DC\u20108 Mission Manager\nDave Easmunt, and the WB\u201057F Program Engineers Shelly Baccus and\nFrank Caldeiro, the Mission Manager William (Bud) Meins, and the Integration\nManager Marty Ross, as well as all of the aircraft crews. The NASA\nAmes Earth Science Project Office made tremendous contributions to the\noperations and overall success of TC4. Our special thanks go to Kent Schiffer,\nMike Gaunce, Sue Tolley, Quincy Allison, Dan Chirica, and the late Steve\nGaines. We also appreciate the support of the NPOL radar, NATIVE trailer,\nand Sat Com groups in Panama and the SMART mobile radar in Costa Rica.\nWe thank the RTMM and REVEAL teams from NASA Marshall Earth\nScience Office and NASA Dryden Test Systems Directorate, respectively,\nfor enabling the collection and display of airborne and ground\u2010based data\nsets, which supported mission planning and enabled critical real\u2010time decision\nmaking. The shipment of the tons of science hardware to San Jose,\nCosta Rica, could not have been accomplished without the tremendous\nefforts of the U.S. Air Force Material Command. We would also like to\nthank the pilots and staff of the NASA C\u20109, NASA G\u20103, and Beale Air force\nBase KC\u2010135 for all their support. We would like to record our special\nappreciation of and thanks to Kathy Thompson for her dedication and effort\nthroughout the planning, operation, and postmission analysis of TC4. Kathy\nwas ably assisted by Rose Kendall, to whom we also send our thanks.\nTommy Thompson's myriad skills were critical to the successful operation\nof the mission in the field. We thank him for being there to make sure, once\nagain, that it all worked. The airport personnel at Juan Santamaria airport\nwere very helpful to the mission. The various Costa Rican government,\nacademic, and commercial organizations we worked with, including CeNAT,\nDGAC, Alterra, ICE, IMN, ADS, and the Servicio de Vigilancia Aerea, were\ninvaluable. The same can be said for the Panamanian government and\nacademic organizations. The Costa Rican National Center for Advanced\nTechnology (CENAT), and especially Oliver G\u00f3mez, were instrumental\nin logistical support, both before and during the mission. The meteorological\nforecasting team in Costa Rica was critical to the success of TC4.\nThis was a joint effort of the Instituto Meteorol\u00f3gico Nacional (IMN),\nthe Centro de Investigaciones Geofisicas (CIGEFI) at the University of\nCosta Rica, and the Instituto Costarricense de Electricidad (ICE). IMN\nteam members were Evelyn Quir\u00f3s Badilla, Gustavo Murillo Zumbado,\nand Eladio Solano Le\u00f3n; the CIGEFI group, under the direction of Jorge\nAmador, included Erick Rivera Fern\u00e1ndez, Marcela Ulate Medrano, Ana\nMar\u00eda Duran Quesada, and Blanca Calder\u00f3n Solera, and Berny Fallas L\u00f3pez\nrepresented ICE. NASA Headquarters management and program managers\nsupported this mission in many meaningful ways. The U.S. Embassies in\nCosta Rica and Panama were especially helpful in coordinating this effort.\nWe appreciate the hospitality of Costa Rican Ambassador Mark Langdale.\nWe appreciate the help of the people of Panama who facilitated the use of\nthe NATIVE trailer and the NPOL radar, and the people of the Galapagos\nwho helped with balloon launching. We especially thank the President\nand people of Costa Rica, who reconstructed the hangar used by the WB\u2010\n57F, loaned us the President's hangar for the ER\u20102, and were very friendly,\nhelpful, and hospitable.\n\nPublished - Toon2010p10963J_Geophys_Res-Atmos.pdf
", "abstract": "The Tropical Composition, Cloud and Climate Coupling Experiment (TC4), was based in Costa Rica and Panama during July and August 2007. The NASA ER-2, DC-8, and WB-57F aircraft flew 26 science flights during TC4. The ER-2 employed 11 instruments as a remote sampling platform and satellite surrogate. The WB-57F used 25 instruments for in situ chemical and microphysical sampling in the tropical tropopause layer (TTL). The DC-8 used 25 instruments to sample boundary layer properties, as well as the radiation, chemistry, and microphysics of the TTL. TC4 also had numerous sonde launches, two ground-based radars, and a ground-based chemical and microphysical sampling site. The major goal of TC4 was to better understand the role that the TTL plays in the Earth's climate and atmospheric chemistry by combining in situ and remotely sensed data from the ground, balloons, and aircraft with data from NASA satellites. Significant progress was made in understanding the microphysical and radiative properties of anvils and thin cirrus. Numerous measurements were made of the humidity and chemistry of the tropical atmosphere from the boundary layer to the lower stratosphere. Insight was also gained into convective transport between the ground and the TTL, and into transport mechanisms across the TTL. New methods were refined and extended to all the NASA aircraft for real-time location relative to meteorological features. The ability to change flight patterns in response to aircraft observations relayed to the ground allowed the three aircraft to target phenomena of interest in an efficient, well-coordinated manner.", "date": "2010-07-15", "date_type": "published", "publication": "Journal of Geophysical Research D", "volume": "115", "publisher": "American Geophysical Union", "pagerange": "Art. No. D00J04", "id_number": "CaltechAUTHORS:20100810-081503208", "issn": "0148-0227", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20100810-081503208", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA" }, { "agency": "University of North Dakota" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2009JD013073", "primary_object": { "basename": "Toon2010p10963J_Geophys_Res-Atmos.pdf", "url": "https://authors.library.caltech.edu/records/bntxk-tpj36/files/Toon2010p10963J_Geophys_Res-Atmos.pdf" }, "resource_type": "article", "pub_year": "2010", "author_list": "Toon, Owen B.; Starr, David O.; et el." }, { "id": "https://authors.library.caltech.edu/records/ykhk9-dz579", "eprint_id": 19321, "eprint_status": "archive", "datestamp": "2023-08-19 03:09:07", "lastmod": "2023-10-23 15:09:15", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Ren-Xinrong", "name": { "family": "Ren", "given": "X." } }, { "id": "Gao-H", "name": { "family": "Gao", "given": "H." } }, { "id": "Zhou-X", "name": { "family": "Zhou", "given": "X." } }, { "id": "Crounse-J-D", "name": { "family": "Crounse", "given": "J. D." }, "orcid": "0000-0001-5443-729X" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Browne-E-C", "name": { "family": "Browne", "given": "E. C." } }, { "id": "LaFranchi-B-W", "name": { "family": "LaFranchi", "given": "B. W." } }, { "id": "Cohen-R-C", "name": { "family": "Cohen", "given": "R. C." }, "orcid": "0000-0001-6617-7691" }, { "id": "McKay-M", "name": { "family": "McKay", "given": "M." } }, { "id": "Goldstein-A-H", "name": { "family": "Goldstein", "given": "A. H." }, "orcid": "0000-0003-4014-4896" }, { "id": "Mao-J", "name": { "family": "Mao", "given": "J." } } ] }, "title": "Measurement of atmospheric nitrous acid at Blodgett Forest during BEARPEX2007", "ispublished": "pub", "full_text_status": "public", "keywords": "Measurement of atmospheric nitrous acid", "note": "\u00a9 Author(s) 2010. This work is distributed\nunder the Creative Commons Attribution 3.0 License.\nReceived: 11 March 2010 \u2013 Published in Atmos. Chem. Phys. Discuss.: 22 March 2010.\nRevised: 27 June 2010 \u2013 Accepted: 5 July 2010 \u2013 Published: 12 July 2010.\n\nThe authors would like to thank Sierra\nPacific Industries for the use of their land and the University of\nCalifornia, Berkeley, Center for Forestry, Blodgett Forest Research\nStation for cooperation in facilitating this study. The authors\nalso thank other research groups participating in this field study\nfor the use of their data in the analysis. This study was partially\nsupported by a National Science Foundation grant (ATM-0914619).\nEdited by: J. Lelieveld.\n\nCorrigendum to \"Measurement of atmospheric nitrous acid at Blodgett Forest during BEARPEX2007\" published in Atmos. Chem. Phys., 10, 6283-6294, 2010\n\nPublished - Ren2010p10849Atmos_Chem_Phys.pdf
Erratum - Corrigendum-to-Ren2010p10849Atmos_Chem_Phys-acp-10-6501-2010.pdf
", "abstract": "Nitrous acid (HONO) is an important precursor of the hydroxyl radical (OH) in the lower troposphere. Understanding HONO chemistry, particularly its sources and contribution to HO_x (=OH+HO_2) production, is very important for understanding atmospheric oxidation processes. A highly sensitive instrument for detecting atmospheric HONO based on wet chemistry followed by liquid waveguide long path absorption photometry was deployed in the Biosphere Effects on Aerosols and Photochemistry Experiment (BEARPEX) at Blodgett Forest, California in late summer 2007. The median diurnal variation shows minimum HONO levels of about 20\u201330 pptv during the day and maximum levels of about 60\u201370 pptv at night, a diurnal pattern quite different from the results at various other forested sites. Measured HONO/NO_2 ratios for a 24-h period ranged from 0.05 to 0.13 with a mean ratio of 0.07. Speciation of reactive nitrogen compounds (NO_y) indicates that HONO accounted for only ~3% of total NO_y. However, due to the fast HONO loss through photolysis, a strong HONO source (1.59 ppbv day^(\u22121)) existed in this environment in order to sustain the observed HONO levels, indicating the significant role of HONO in NO_y cycling. The wet chemistry HONO measurements were compared to the HONO measurements made with a Chemical Ionization Mass Spectrometer (CIMS) over a three-day period. Good agreement was obtained between the measurements from the two different techniques. Using the expansive suite of photochemical and meteorological measurements, the contribution of HONO photolysis to HO_x budget was calculated to be relatively small (6%) compared to results from other forested sites. The lower HONO mixing ratio and thus its smaller contribution to HO_x production are attributed to the unique meteorological conditions and low acid precipitation at Blodgett Forest. Further studies of HONO in this kind of environment are needed to test this hypothesis and to improve our understanding of atmospheric oxidation and nitrogen budget.", "date": "2010-07-12", "date_type": "published", "publication": "Atmospheric Chemistry and Physics", "volume": "10", "number": "13", "publisher": "European Geosciences Union", "pagerange": "6283-6294", "id_number": "CaltechAUTHORS:20100806-140611677", "issn": "1680-7316", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20100806-140611677", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "ATM-0914619" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/acp-10-6283-2010", "primary_object": { "basename": "Corrigendum-to-Ren2010p10849Atmos_Chem_Phys-acp-10-6501-2010.pdf", "url": "https://authors.library.caltech.edu/records/ykhk9-dz579/files/Corrigendum-to-Ren2010p10849Atmos_Chem_Phys-acp-10-6501-2010.pdf" }, "related_objects": [ { "basename": "Ren2010p10849Atmos_Chem_Phys.pdf", "url": "https://authors.library.caltech.edu/records/ykhk9-dz579/files/Ren2010p10849Atmos_Chem_Phys.pdf" } ], "resource_type": "article", "pub_year": "2010", "author_list": "Ren, X.; Gao, H.; et el." }, { "id": "https://authors.library.caltech.edu/records/nx1ws-qvt39", "eprint_id": 103570, "eprint_status": "archive", "datestamp": "2023-08-19 03:09:47", "lastmod": "2023-10-23 15:09:18", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Ren-Xinrong", "name": { "family": "Ren", "given": "X." }, "orcid": "0000-0001-9974-1666" }, { "id": "Gao-H", "name": { "family": "Gao", "given": "H." } }, { "id": "Zhou-X", "name": { "family": "Zhou", "given": "X." } }, { "id": "Crounse-J-D", "name": { "family": "Crounse", "given": "J. D." }, "orcid": "0000-0001-5443-729X" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Browne-E-C", "name": { "family": "Browne", "given": "E. C." } }, { "id": "LaFranchi-B-W", "name": { "family": "LaFranchi", "given": "B. W." } }, { "id": "Cohen-R-C", "name": { "family": "Cohen", "given": "R. C." }, "orcid": "0000-0001-6617-7691" }, { "id": "McKay-M", "name": { "family": "McKay", "given": "M." } }, { "id": "Goldstein-A-H", "name": { "family": "Goldstein", "given": "A. H." }, "orcid": "0000-0003-4014-4896" }, { "id": "Mao-J", "name": { "family": "Mao", "given": "J." } } ] }, "title": "Measurement of atmospheric nitrous acid at Bodgett Forest during BEARPEX2007", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 Author(s) 2010. This work is distributed under the Creative Commons Attribution 3.0 License. \n\nReceived: 11 Mar 2010 \u2013 Discussion started: 22 Mar 2010 \u2013 Revised: 27 Jun 2010 \u2013 Accepted: 05 Jul 2010 \u2013 Published: 12 Jul 2010. \n\nSpecial issue: Biosphere Effects on Aerosols and Photochemistry Experiment: BEARPEX. Editor(s): A. Guenther, J. Lelieveld, and J. Williams. \n\nThe authors would like to thank Sierra Pacific Industries for the use of their land and the University of California, Berkeley, Center for Forestry, Blodgett Forest Research Station for cooperation in facilitating this study. The authors also thank other research groups participating in this field study for the use of their data in the analysis. This study was partially supported by a National Science Foundation grant (ATM-0914619). \n\nEdited by: J. Lelieveld\n\nRen, X., Gao, H., Zhou, X., Crounse, J. D., Wennberg, P. O., Browne, E. C., LaFranchi, B. W., Cohen, R. C., McKay, M., Goldstein, A. H., and Mao, J.: Corrigendum to \"Measurement of atmospheric nitrous acid at Blodgett Forest during BEARPEX2007\" published in Atmos. Chem. Phys., 10, 6283-6294, 2010, Atmos. Chem. Phys., 10, 6501\u20136501, https://doi.org/10.5194/acp-10-6501-2010, 2010.\n\nPublished - acp-10-6283-2010.pdf
Erratum - acp-10-6501-2010.pdf
", "abstract": "Nitrous acid (HONO) is an important precursor of the hydroxyl radical (OH) in the lower troposphere. Understanding HONO chemistry, particularly its sources and contribution to HO_x (=OH+HO\u2082) production, is very important for understanding atmospheric oxidation processes. A highly sensitive instrument for detecting atmospheric HONO based on wet chemistry followed by liquid waveguide long path absorption photometry was deployed in the Biosphere Effects on Aerosols and Photochemistry Experiment (BEARPEX) at Blodgett Forest, California in late summer 2007. The median diurnal variation shows minimum HONO levels of about 20\u201330 pptv during the day and maximum levels of about 60\u201370 pptv at night, a diurnal pattern quite different from the results at various other forested sites. Measured HONO/NO\u2082 ratios for a 24-h period ranged from 0.05 to 0.13 with a mean ratio of 0.07. Speciation of reactive nitrogen compounds (NO_y) indicates that HONO accounted for only ~3% of total NO_y. However, due to the fast HONO loss through photolysis, a strong HONO source (1.59 ppbv day\u207b\u00b9) existed in this environment in order to sustain the observed HONO levels, indicating the significant role of HONO in NO_y cycling. The wet chemistry HONO measurements were compared to the HONO measurements made with a Chemical Ionization Mass Spectrometer (CIMS) over a three-day period. Good agreement was obtained between the measurements from the two different techniques. Using the expansive suite of photochemical and meteorological measurements, the contribution of HONO photolysis to HO_x budget was calculated to be relatively small (6%) compared to results from other forested sites. The lower HONO mixing ratio and thus its smaller contribution to HO_x production are attributed to the unique meteorological conditions and low acid precipitation at Blodgett Forest. Further studies of HONO in this kind of environment are needed to test this hypothesis and to improve our understanding of atmospheric oxidation and nitrogen budget.", "date": "2010-07-12", "date_type": "published", "publication": "Atmospheric Chemistry and Physics", "volume": "10", "number": "13", "publisher": "European Geosciences Union", "pagerange": "6283-6294", "id_number": "CaltechAUTHORS:20200529-093435137", "issn": "1680-7324", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200529-093435137", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "ATM-0914619" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/acp-10-6283-2010", "primary_object": { "basename": "acp-10-6283-2010.pdf", "url": "https://authors.library.caltech.edu/records/nx1ws-qvt39/files/acp-10-6283-2010.pdf" }, "related_objects": [ { "basename": "acp-10-6501-2010.pdf", "url": "https://authors.library.caltech.edu/records/nx1ws-qvt39/files/acp-10-6501-2010.pdf" } ], "resource_type": "article", "pub_year": "2010", "author_list": "Ren, X.; Gao, H.; et el." }, { "id": "https://authors.library.caltech.edu/records/y717s-ghc81", "eprint_id": 19386, "eprint_status": "archive", "datestamp": "2023-08-23 23:32:14", "lastmod": "2023-10-20 20:38:22", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Mao-J", "name": { "family": "Mao", "given": "J." } }, { "id": "St-Clair-J-M", "name": { "family": "St. Clair", "given": "J. M." }, "orcid": "0000-0002-9367-5749" }, { "id": "Crounse-J-D", "name": { "family": "Crounse", "given": "J. D." }, "orcid": "0000-0001-5443-729X" }, { "id": "Spencer-K-M", "name": { "family": "Spencer", "given": "K. M." } }, { "id": "Beaver-M-R", "name": { "family": "Beaver", "given": "M. R." } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "Chemistry of hydrogen oxide radicals (HO_x) in the Arctic troposphere in spring", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 Author(s) 2010. This work is distributed\nunder the Creative Commons Attribution 3.0 License.\nReceived: 3 March 2010 \u2013 Published in Atmos. Chem. Phys. Discuss.: 11 March 2010.\nRevised: 13 June 2010 \u2013 Accepted: 21 June 2010 \u2013 Published: 1 July 2010.\nThe authors would like to thank Scot T. Martin,\nHongyu Liu, Charles E. Miller, Richard A. Ferrare,\nKarl D. Froyd and Daniel M. Murphy for helpful discussions.\nWe also would like to thank Yuhang Wang for providing the\nTOPSE dataset, Huisheng Bian for providing Fast-JX updates and\nDirk Richter for contributing to the HCHO measurement. J. Mao\nalso thanks David M. Shelow and the NASA DC-8 crew for their\ngenerous help with making HOx measurements on the aircraft.\nThis work was supported by the NASA Tropospheric Chemistry\nProgram.\nEdited by: P. Monks.\n\nPublished - Mao2010p10844Atmos_Chem_Phys.pdf
", "abstract": "We use observations from the April 2008 NASA ARCTAS aircraft campaign to the North American Arctic, interpreted with a global 3-D chemical transport model (GEOS-Chem), to better understand the sources and cycling of hydrogen oxide radicals (HO_x\u2261H+OH+peroxy radicals) and their reservoirs (HO_y\u2261HO_x+peroxides) in the springtime Arctic atmosphere. We find that a standard gas-phase chemical mechanism overestimates the observed HO_2 and H_2O_2 concentrations. Computation of HO_x and HO_y gas-phase chemical budgets on the basis of the aircraft observations also indicates a large missing sink for both. We hypothesize that this could reflect HO_2 uptake by aerosols, favored by low temperatures and relatively high aerosol loadings, through a mechanism that does not produce H_2O_2. We implemented such an uptake of HO_2 by aerosol in the model using a standard reactive uptake coefficient parameterization with \u03b3(HO_2) values ranging from 0.02 at 275 K to 0.5 at 220 K. This successfully reproduces the concentrations and vertical distributions of the different HO_x species and HO_y reservoirs. HO_2 uptake by aerosol is then a major HO_x and HO_y sink, decreasing mean OH and HO_2 concentrations in the Arctic troposphere by 32% and 31% respectively. Better rate and product data for HO_2 uptake by aerosol are needed to understand this role of aerosols in limiting the oxidizing power of the Arctic atmosphere.", "date": "2010-07-01", "date_type": "published", "publication": "Atmospheric Chemistry and Physics", "volume": "10", "number": "13", "publisher": "European Geosciences Union", "pagerange": "5823-5838", "id_number": "CaltechAUTHORS:20100811-084643946", "issn": "1680-7316", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20100811-084643946", "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": "10.5194/acp-10-5823-2010", "primary_object": { "basename": "Mao2010p10844Atmos_Chem_Phys.pdf", "url": "https://authors.library.caltech.edu/records/y717s-ghc81/files/Mao2010p10844Atmos_Chem_Phys.pdf" }, "resource_type": "article", "pub_year": "2010", "author_list": "Mao, J.; St. Clair, J. M.; et el." }, { "id": "https://authors.library.caltech.edu/records/6707x-9x778", "eprint_id": 18904, "eprint_status": "archive", "datestamp": "2023-08-19 02:50:15", "lastmod": "2023-10-20 19:10:46", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Chan-Man-Nin", "name": { "family": "Chan", "given": "Man Nin" }, "orcid": "0000-0002-2384-2695" }, { "id": "Surratt-Jason-D", "name": { "family": "Surratt", "given": "Jason D." }, "orcid": "0000-0002-6833-1450" }, { "id": "Claeys-Magda", "name": { "family": "Claeys", "given": "Magda" }, "orcid": "0000-0003-2278-8014" }, { "id": "Edgerton-Eric-S", "name": { "family": "Edgerton", "given": "Eric S." } }, { "id": "Tanner-Roger-L", "name": { "family": "Tanner", "given": "Roger L." } }, { "id": "Shaw-Stephanie-L", "name": { "family": "Shaw", "given": "Stephanie L." }, "orcid": "0000-0001-8198-4184" }, { "id": "Zheng-Mei", "name": { "family": "Zheng", "given": "Mei" } }, { "id": "Knipping-Eladio-M", "name": { "family": "Knipping", "given": "Eladio M." }, "orcid": "0000-0002-9654-9019" }, { "id": "Eddingsaas-Nathan-C", "name": { "family": "Eddingsaas", "given": "Nathan C." }, "orcid": "0000-0003-1539-5415" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Seinfeld-J-H", "name": { "family": "Seinfeld", "given": "John H." }, "orcid": "0000-0003-1344-4068" } ] }, "title": "Characterization and Quantification of Isoprene-Derived Epoxydiols in Ambient Aerosol in the Southeastern United States", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2010 American Chemical Society. \n\nReceived February 22, 2010. Revised manuscript received May 2, 2010. Accepted May 4, 2010. Publication Date (Web): May 17, 2010. \n\nThis work was supported by the Electric Power Research Institute and the Southern Company, Birmingham, AL. We acknowledge all members of the AMIGAS for their support during the field campaign. We thank Arthur W. H. Chan and Christine L. Loza for the generation of the low-NO_x isoprene SOA and Kathryn E. Kautzman for assistance with the GC/TOFMS measurement.\n\nSupplemental Material - es100596b_si_001.pdf
", "abstract": "Isoprene-derived epoxydiols (IEPOX) are identified in ambient aerosol samples for the first time, together with other previously identified isoprene tracers (i.e., 2-methyltetrols, 2-methylglyceric acid, C5-alkenetriols, and organosulfate derivatives of 2-methyltetrols). Fine ambient aerosol collected in downtown Atlanta, GA and rural Yorkville, GA during the 2008 August Mini-Intensive Gas and Aerosol Study (AMIGAS) was analyzed using both gas chromatography/quadrupole mass spectrometry (GC/MS) and gas chromatography/time-of-flight mass spectrometry (GC/TOFMS) with prior trimethylsilylation. Mass concentrations of IEPOX ranged from ~1 to 24 ng m^(\u22123) in the aerosol collected from the two sites. Detection of particle-phase IEPOX in the AMIGAS samples supports recent laboratory results that gas-phase IEPOX produced from the photooxidation of isoprene under low-NO_x conditions is a key precursor of ambient isoprene secondary organic aerosol (SOA) formation. On average, the sum of the mass concentrations of IEPOX and the measured isoprene SOA tracers accounted for about 3% of the organic carbon, demonstrating the significance of isoprene oxidation to the formation of ambient aerosol in this region.", "date": "2010-06-15", "date_type": "published", "publication": "Environmental Science and Technology", "volume": "44", "number": "12", "publisher": "American Chemical Society", "pagerange": "4590-4596", "id_number": "CaltechAUTHORS:20100706-092745845", "issn": "0013-936X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20100706-092745845", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Electric Power Research Institute (EPRI)" }, { "agency": "Southern Company (Birmingham, AL)" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1021/es100596b", "primary_object": { "basename": "es100596b_si_001.pdf", "url": "https://authors.library.caltech.edu/records/6707x-9x778/files/es100596b_si_001.pdf" }, "resource_type": "article", "pub_year": "2010", "author_list": "Chan, Man Nin; Surratt, Jason D.; et el." }, { "id": "https://authors.library.caltech.edu/records/h3x6n-hbt02", "eprint_id": 18898, "eprint_status": "archive", "datestamp": "2023-08-23 23:30:27", "lastmod": "2023-10-20 19:10:19", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "DeCarlo-P-F", "name": { "family": "DeCarlo", "given": "P. F." } }, { "id": "Ulbrich-I-M", "name": { "family": "Ulbrich", "given": "I. M." } }, { "id": "Crounse-J-D", "name": { "family": "Crounse", "given": "J." }, "orcid": "0000-0001-5443-729X" }, { "id": "de-Foy-B", "name": { "family": "de Foy", "given": "B." } }, { "id": "Dunlea-E-J", "name": { "family": "Dunlea", "given": "E. J." } }, { "id": "Aiken-A-C", "name": { "family": "Aiken", "given": "A. C." } }, { "id": "Knapp-D", "name": { "family": "Knapp", "given": "D." } }, { "id": "Weinheimer-A-J", "name": { "family": "Weinheimer", "given": "A. J." }, "orcid": "0000-0001-6175-8286" }, { "id": "Campos-T", "name": { "family": "Campos", "given": "T." } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Jimenez-J-L", "name": { "family": "Jimenez", "given": "J. L." }, "orcid": "0000-0001-6203-1847" } ] }, "title": "Investigation of the sources and processing of organic aerosol over the Central Mexican Plateau from aircraft measurements during MILAGRO", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 Author(s) 2010. This work is distributed\nunder the Creative Commons Attribution 3.0 License.\n\nReceived: 14 January 2010 \u2013 Published in Atmos. Chem. Phys. Discuss.: 2 February 2010.\nRevised: 20 May 2010 \u2013 Accepted: 8 June 2010 \u2013 Published: 15 June 2010.\nThis study was supported by NSF (ATM-\n0449815, ATM-0513116, ATM-0810950), NSF/UCAR S05-39607,\nNOAA (NA08OAR4310565), and EPA STAR (RD-83216101-0\nand R833747). PFD is grateful for an EPA STAR graduate\nfellowship (FP-91650801) and an NSF International Postdoctoral\nFellowship (0701013). IMU and ACA thank NASA for graduate\nfellowships (NNG05GQ50H and NNG04GR06H).\nEdited by: L. Molina.\n\nPublished - DeCarlo2010p10555Atmos_Chem_Phys.pdf
", "abstract": "Organic aerosol (OA) represents approximately half of the submicron aerosol in Mexico City and the Central Mexican Plateau. This study uses the high time resolution measurements performed onboard the NCAR/NSF C-130 aircraft during the MILAGRO/MIRAGE-Mex field campaign in March 2006 to investigate the sources and chemical processing of the OA in this region. An examination of the OA/\u0394CO ratio evolution as a function of photochemical age shows distinct behavior in the presence or absence of substantial open biomass burning (BB) influence, with the latter being consistent with other studies in polluted areas. In addition, we present results from Positive Matrix Factorization (PMF) analysis of 12-s High-Resolution Time-of-Flight Aerosol Mass Spectrometer (HR-ToF-AMS) OA spectra. Four components were resolved. Three of the components contain substantial organic oxygen and are termed semivolatile oxygenated OA (SV-OOA), low-volatility OOA (LV-OOA), and biomass burning OA (BBOA). A reduced \"hydrocarbon-like OA\" (HOA) component is also resolved. LV-OOA is highly oxygenated (atomic O/C~1) and is aged organic aerosol linked to regional airmasses, with likely contributions from pollution, biomass burning, and other sources. SV-OOA is strongly correlated with ammonium nitrate, Ox, and the Mexico City Basin. We interpret SV-OOA as secondary OA which is nearly all (>90%) anthropogenic in origin. In the absence of biomass burning it represents the largest fraction of OA over the Mexico City basin, consistent with other studies in this region. BBOA is identified as arising from biomass burning sources due to a strong correlation with HCN, and the elevated contribution of the ion C_2H_4O_2^+ (m/z 60, a marker for levoglucosan and other primary BB species). WRF-FLEXPART calculated fire impact factors (FIF) show good correlation with BBOA mass concentrations within the basin, but show location offsets in the far field due to model transport errors. This component is small or absent when forest fires are suppressed by precipitation. Since PMF factors represent organic species grouped by chemical similarity, additional postprocessing is needed to more directly apportion OA amounts to sources, which is done here based on correlations to different tracers. The postprocessed AMS results are similar to those from an independent source apportionment based on multiple linear regression with gas-phase tracers. During a flight with very high forest fire intensity near the basin OA arising from open BB represents ~66% of the OA mass in the basin and contributes similarly to OA mass in the outflow. Aging and SOA formation of BB emissions is estimated to add OA mass equivalent to about ~32\u201342% of the primary BBOA over several hours to a day.", "date": "2010-06-15", "date_type": "published", "publication": "Atmospheric Chemistry and Physics", "volume": "10", "number": "12", "publisher": "European Geosciences Union", "pagerange": "5257-5280", "id_number": "CaltechAUTHORS:20100701-131659744", "issn": "1680-7316", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20100701-131659744", "rights": "This work is distributed under the Creative Commons Attribution 3.0 License.", "funders": { "items": [ { "agency": "NSF", "grant_number": "ATM-0449815" }, { "agency": "NSF", "grant_number": "ATM-0513116" }, { "agency": "NSF", "grant_number": "ATM-0810950" }, { "agency": "NSF", "grant_number": "OISE-0701013" }, { "agency": "NSF", "grant_number": "S05-39607" }, { "agency": "National Oceanic and Atmospheric Administration (NOAA)", "grant_number": "NA08OAR4310565" }, { "agency": "Environmental Protection Agency (EPA)", "grant_number": "RD-83216101-0" }, { "agency": "Environmental Protection Agency (EPA)", "grant_number": "R833747" }, { "agency": "Environmental Protection Agency (EPA)", "grant_number": "FP-91650801" }, { "agency": "NASA", "grant_number": "NNG05GQ50H" }, { "agency": "NASA", "grant_number": "NNG04GR06H" }, { "agency": "University Corporation for Atmospheric Research (UCAR)" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/acp-10-5257-2010", "primary_object": { "basename": "DeCarlo2010p10555Atmos_Chem_Phys.pdf", "url": "https://authors.library.caltech.edu/records/h3x6n-hbt02/files/DeCarlo2010p10555Atmos_Chem_Phys.pdf" }, "resource_type": "article", "pub_year": "2010", "author_list": "DeCarlo, P. F.; Ulbrich, I. M.; et el." }, { "id": "https://authors.library.caltech.edu/records/mg7j9-q5798", "eprint_id": 20723, "eprint_status": "archive", "datestamp": "2023-08-23 23:33:03", "lastmod": "2023-10-20 23:22:35", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Avery-M-A", "name": { "family": "Avery", "given": "Melody" } }, { "id": "Twohy-C-H", "name": { "family": "Twohy", "given": "Cynthia" } }, { "id": "McCabe-D-C", "name": { "family": "McCabe", "given": "David" } }, { "id": "Joiner-J", "name": { "family": "Joiner", "given": "Joanna" }, "orcid": "0000-0003-4278-1020" }, { "id": "Severance-K", "name": { "family": "Severance", "given": "Kurt" } }, { "id": "Atlas-E-L", "name": { "family": "Atlas", "given": "Elliot" }, "orcid": "0000-0003-3847-5346" }, { "id": "Blake-D-R", "name": { "family": "Blake", "given": "Donald" } }, { "id": "Bui-T-P", "name": { "family": "Bui", "given": "T. P." } }, { "id": "Crounse-J-D", "name": { "family": "Crounse", "given": "John" }, "orcid": "0000-0001-5443-729X" }, { "id": "Dibb-J-E", "name": { "family": "Dibb", "given": "Jack" }, "orcid": "0000-0003-3096-7709" }, { "id": "Diskin-G-S", "name": { "family": "Diskin", "given": "Glenn" }, "orcid": "0000-0002-3617-0269" }, { "id": "Lawson-P", "name": { "family": "Lawson", "given": "Paul" } }, { "id": "McGill-Matthew", "name": { "family": "McGill", "given": "Matthew" } }, { "id": "Rogers-D-C", "name": { "family": "Rogers", "given": "David" } }, { "id": "Sachse-G-W", "name": { "family": "Sachse", "given": "Glen" } }, { "id": "Scheuer-E", "name": { "family": "Scheuer", "given": "Eric" } }, { "id": "Thompson-A-M", "name": { "family": "Thompson", "given": "Anne M." } }, { "id": "Trepte-C", "name": { "family": "Trepte", "given": "Charles" } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Ziemke-J", "name": { "family": "Ziemke", "given": "Jerald" } } ] }, "title": "Convective distribution of tropospheric ozone and tracers in the Central American ITCZ region: Evidence from observations during TC4", "ispublished": "pub", "full_text_status": "public", "keywords": "convection; vertical transport; chemical tracers", "note": "\u00a9 2010 American Geophysical Union. \n\nReceived 28 October 2009; revised 17 May 2010; accepted 7 June 2010; published 13 October 2010. \n\nThe authors thank the NASA Middle Atmosphere\nand Tropospheric Chemistry Programs for funding, and Program\nManagers Michael Kurylo and Hal Maring for launching sondes from the\nDC\u20108. We thank Lenny Pfister for all sorts of meteorological information\nand consultation. We thank Gary Morris for providing the Las Tablas sonde\ndata, and we thank Alex Bryan and David Lutz for launching all of these\nPanama sondes. Holger Voemel provided the Alajuela ozonesonde data,\nand Ru\u2010shan Gao provided ozone measurements from the WB\u201057. Ross\nSalawitch and Tim Canty provided the plot of total organic bromine, and\nwe are grateful for many helpful discussions. We also thank Mario Rana\nfor DC\u20108 fast\u2010response tracer lag correlations and Ali Aknan for \"Chemical\nDigital Atlas\" plots and calculations of statistical vertical tracer distributions\nduring various tropospheric aircraft field missions (http://www\u2010air.larc.nasa.gov/cgi\u2010bin/datlas). We are grateful to K.A. Masserie and E. Dlugokencky at\nNOAA CMDL for the Barbados and Bahia methane measurements, and to\nPat Minnis and his group for the GOES satellite images and loops.\n\nPublished - Avery2010p11768J_Geophys_Res-Atmos.pdf
", "abstract": "During the Tropical Composition, Clouds and Climate Coupling (TC4) experiment that occurred in July and August of 2007, extensive sampling of active convection in the ITCZ region near Central America was performed from multiple aircraft and satellite sensors. As part of a sampling strategy designed to study cloud processes, the NASA ER-2, WB-57 and DC-8 flew in stacked \"racetrack patterns\" in convective cells. On July 24, 2007, the ER-2 and DC-8 probed an actively developing storm and the DC-8 was hit by lightning. Case studies of this flight, and of convective outflow on August 5, 2007 reveal a significant anti-correlation between ozone and condensed cloud water content. With little variability in the boundary layer and a vertical gradient, low ozone in the upper troposphere indicates convective transport. Because of the large spatial and temporal variability in surface CO and other pollutants in this region, low ozone is a better convective indicator. Lower tropospheric tracers methyl hydrogen peroxide, total organic bromine and calcium substantiate the ozone results. OMI measurements of mean upper tropospheric ozone near convection show lower ozone in convective outflow. A mass balance estimation of the amount of convective turnover below the tropical tropopause transition layer (TTL) is 50%, with an altitude of maximum convective outflow located between 10 and 11 km, 4 km below the cirrus anvil tops. It appears that convective lofting in this region of the ITCZ is either a two-stage or a rapid mixing process, because undiluted boundary layer air is never sampled in the convective outflow.", "date": "2010-05-27", "date_type": "published", "publication": "Journal of Geophysical Research D", "volume": "115", "number": "D10", "publisher": "American Geophysical Union", "pagerange": "Art. No. D00J21", "id_number": "CaltechAUTHORS:20101109-075906062", "issn": "0148-0227", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20101109-075906062", "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": "10.1029/2009JD013450", "primary_object": { "basename": "Avery2010p11768J_Geophys_Res-Atmos.pdf", "url": "https://authors.library.caltech.edu/records/mg7j9-q5798/files/Avery2010p11768J_Geophys_Res-Atmos.pdf" }, "resource_type": "article", "pub_year": "2010", "author_list": "Avery, Melody; Twohy, Cynthia; et el." }, { "id": "https://authors.library.caltech.edu/records/r3zgd-5hq40", "eprint_id": 18483, "eprint_status": "archive", "datestamp": "2023-08-21 23:45:08", "lastmod": "2023-10-20 16:26:10", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Surratt-Jason-D", "name": { "family": "Surratt", "given": "Jason D." }, "orcid": "0000-0002-6833-1450" }, { "id": "Chan-Arthur-W-H", "name": { "family": "Chan", "given": "Arthur W. H." }, "orcid": "0000-0001-7392-4237" }, { "id": "Eddingsaas-Nathan-C", "name": { "family": "Eddingsaas", "given": "Nathan C." }, "orcid": "0000-0003-1539-5415" }, { "id": "Chan-Man-Nin", "name": { "family": "Chan", "given": "ManNin" }, "orcid": "0000-0002-2384-2695" }, { "id": "Loza-Christine-L", "name": { "family": "Loza", "given": "Christine L." } }, { "id": "Kwan-Alan-J", "name": { "family": "Kwan", "given": "Alan J." } }, { "id": "Hersey-Scott-P", "name": { "family": "Hersey", "given": "Scott P." } }, { "id": "Flagan-R-C", "name": { "family": "Flagan", "given": "Richard C." }, "orcid": "0000-0001-5690-770X" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Seinfeld-J-H", "name": { "family": "Seinfeld", "given": "John H." }, "orcid": "0000-0003-1344-4068" } ] }, "title": "Reactive intermediates revealed in secondary organic aerosol formation from isoprene", "ispublished": "pub", "full_text_status": "public", "keywords": "acid-catalyzed particle-phase reactions; epoxides; methacryloylperoxynitrate; organosulfates", "note": "\u00a9 2010 by the National Academy of Sciences.\nEdited by Barbara J. Finlayson-Pitts, University of California, Irvine, Irvine, CA, and approved November 23, 2009 (received for review September 30, 2009).\nPublished online before print December 31, 2009.\n\nThis work was supported by the Office of Science\n(Biological and Environmental Research), Electric Power Research Institute,\nU.S. Department of Energy Grant DE-FG02-05ER63983, and U.S. Environmental\nProtection Agency (EPA) STAR agreement RD-833749. The CIMS instrument\nwas purchased as part of a major research instrumentation grant\nfrom the National Science Foundation (Grant ATM-0619783); assembly and\ntesting was supported by the Davidow Discovery Fund. We thank Andreas\nK\u00fcrten for assembling the CIMS instrument and John D. Crounse for synthesizing\nand characterizing (with H-NMR) the BEPOX. The Waters UPLC-LCT\nPremier XT time-of-flight mass spectrometer was purchased in 2006 with a\ngrant from the National Science Foundation, Chemistry Research Instrumentation\nand Facilities Program (Grant CHE-0541745). N.C.E. was supported by\nthe Camille and Henry Dreyfus Postdoctoral Program in Environmental\nChemistry. We also thank Magda Claeys for useful discussions.\n\nAuthor contributions: J.D.S., A.W.H.C., N.C.E., R.C.F., P.O.W., and J.H.S. designed\nresearch; J.D.S., A.W.H.C., N.C.E., M.N.C., C.L.L., A.J.K., and S.P.H. performed research;\nJ.D.S., A.W.H.C., and N.C.E. analyzed data; and J.D.S., A.W.H.C., N.C.E., P.O.W., and J.H.S.\nwrote the paper.\n\nPublished - Surratt2010p9803P_Natl_Acad_Sci_Usa.pdf
Supplemental Material - pnas.0911114107_SI.pdf
", "abstract": "Isoprene is a significant source of atmospheric organic aerosol; however, the oxidation pathways that lead to secondary organic aerosol (SOA) have remained elusive. Here, we identify the role of two key reactive intermediates, epoxydiols of isoprene (IEPOX = \u03b2-IEPOX + \u03b4-IEPOX) and methacryloylperoxynitrate (MPAN), which are formed during isoprene oxidation under low- and high-NO_x conditions, respectively. Isoprene low-NO_x SOA is enhanced in the presence of acidified sulfate seed aerosol (mass yield 28.6%) over that in the presence of neutral aerosol (mass yield 1.3%). Increased uptake of IEPOX by acid-catalyzed particle-phase reactions is shown to explain this enhancement. Under high-NO_x conditions, isoprene SOA formation occurs through oxidation of its second-generation product, MPAN. The similarity of the composition of SOA formed from the photooxidation of MPAN to that formed from isoprene and methacrolein demonstrates the role of MPAN in the formation of isoprene high-NO_x SOA. Reactions of IEPOX and MPAN in the presence of anthropogenic pollutants (i.e., acidic aerosol produced from the oxidation of SO_2 and NO_2, respectively) could be a substantial source of \"missing urban SOA\" not included in current atmospheric models.", "date": "2010-04-13", "date_type": "published", "publication": "Proceedings of the National Academy of Sciences of the United States of America", "volume": "107", "number": "15", "publisher": "National Academy of Sciences", "pagerange": "6640-6645", "id_number": "CaltechAUTHORS:20100527-135521520", "issn": "0027-8424", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20100527-135521520", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-FG02-05ER63983" }, { "agency": "Environmental Protection Agency (EPA)", "grant_number": "RD-833749" }, { "agency": "NSF", "grant_number": "ATM-0619783" }, { "agency": "NSF", "grant_number": "CHE-0541745" }, { "agency": "Davidow Discovery Fund" }, { "agency": "Camille and Henry Dreyfus Foundation" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1073/pnas.0911114107", "pmcid": "PMC2872383", "primary_object": { "basename": "Surratt2010p9803P_Natl_Acad_Sci_Usa.pdf", "url": "https://authors.library.caltech.edu/records/r3zgd-5hq40/files/Surratt2010p9803P_Natl_Acad_Sci_Usa.pdf" }, "related_objects": [ { "basename": "pnas.0911114107_SI.pdf", "url": "https://authors.library.caltech.edu/records/r3zgd-5hq40/files/pnas.0911114107_SI.pdf" } ], "resource_type": "article", "pub_year": "2010", "author_list": "Surratt, Jason D.; Chan, Arthur W. H.; et el." }, { "id": "https://authors.library.caltech.edu/records/ezpwe-14w58", "eprint_id": 17998, "eprint_status": "archive", "datestamp": "2023-08-22 00:52:58", "lastmod": "2023-10-20 15:30:06", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Adhikari-B", "name": { "family": "Adhikari", "given": "B." } }, { "id": "Carmichael-G-R", "name": { "family": "Carmichael", "given": "G. R." } }, { "id": "Kulkarni-S", "name": { "family": "Kulkarni", "given": "S." } }, { "id": "Wei-C", "name": { "family": "Wei", "given": "C." } }, { "id": "Tang-Y", "name": { "family": "Tang", "given": "Y." } }, { "id": "D'Allura-A", "name": { "family": "D'Allura", "given": "A." } }, { "id": "Mena-Carrasco-M", "name": { "family": "Mena-Carrasco", "given": "M." } }, { "id": "Streets-D-G", "name": { "family": "Streets", "given": "D. G." } }, { "id": "Zhang-Q", "name": { "family": "Zhang", "given": "Q." } }, { "id": "Pierce-R-B", "name": { "family": "Pierce", "given": "R. B." } }, { "id": "Al-Saadi-J-A", "name": { "family": "Al-Saadi", "given": "J. A." } }, { "id": "Emmons-L-K", "name": { "family": "Emmons", "given": "L. K." } }, { "id": "Pfister-G-G", "name": { "family": "Pfister", "given": "G. G." } }, { "id": "Avery-M-A", "name": { "family": "Avery", "given": "M. A." } }, { "id": "Barrick-J-D", "name": { "family": "Barrick", "given": "J. D." } }, { "id": "Blake-D-R", "name": { "family": "Blake", "given": "D. R." } }, { "id": "Brune-W-H", "name": { "family": "Brune", "given": "W. H." }, "orcid": "0000-0002-1609-4051" }, { "id": "Cohen-R-C", "name": { "family": "Cohen", "given": "R. C." }, "orcid": "0000-0001-6617-7691" }, { "id": "Dibb-J-E", "name": { "family": "Dibb", "given": "J. E." }, "orcid": "0000-0003-3096-7709" }, { "id": "Fried-A", "name": { "family": "Fried", "given": "A." } }, { "id": "Heikes-B-G", "name": { "family": "Heikes", "given": "B. G." } }, { "id": "Huey-L-G", "name": { "family": "Huey", "given": "L. G." }, "orcid": "0000-0002-0518-7690" }, { "id": "O'Sullivan-D-W", "name": { "family": "O'Sullivan", "given": "D. W." } }, { "id": "Sachse-G-W", "name": { "family": "Sachse", "given": "G. W." } }, { "id": "Shetter-R-E", "name": { "family": "Shetter", "given": "R. E." } }, { "id": "Singh-H-B", "name": { "family": "Singh", "given": "H. B." } }, { "id": "Campos-T-L", "name": { "family": "Campos", "given": "T. L." } }, { "id": "Cantrell-C-A", "name": { "family": "Cantrell", "given": "C. A." } }, { "id": "Flocke-F-M", "name": { "family": "Flocke", "given": "F. M." } }, { "id": "Dunlea-E-J", "name": { "family": "Dunlea", "given": "E. J." } }, { "id": "Jimenez-J-L", "name": { "family": "Jimenez", "given": "J. L." }, "orcid": "0000-0001-6203-1847" }, { "id": "Weinheimer-A-J", "name": { "family": "Weinheimer", "given": "A. J." }, "orcid": "0000-0001-6175-8286" }, { "id": "Crounse-J-D", "name": { "family": "Crounse", "given": "J. D." }, "orcid": "0000-0001-5443-729X" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Schauer-J-J", "name": { "family": "Schauer", "given": "J. J." } }, { "id": "Stone-E-A", "name": { "family": "Stone", "given": "E. A." } }, { "id": "Jaffe-D-A", "name": { "family": "Jaffe", "given": "D. A." } }, { "id": "Reidmiller-D-R", "name": { "family": "Reidmiller", "given": "D. R." } } ] }, "title": "A regional scale modeling analysis of aerosol and trace gas distributions over the eastern Pacific during the INTEX-B field campaign", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 Author(s) 2010. This work is distributed under\nthe Creative Commons Attribution 3.0 License.\nPublished by Copernicus Publications on behalf of the European Geosciences Union.\nReceived: 19 July 2009 \u2013 Published in Atmos. Chem. Phys. Discuss.: 3 August 2009\nRevised: 15 February 2010 \u2013 Accepted: 21 February 2010 \u2013 Published: 1 March 2010. We would like to thank the INTEX-B science\nteam. This work was supported by a NASA grants (NNG04GC58G\nand INTEX-B). The heterogeneous chemistry portion was based on\nwork done under a NSF grant (0613124). The authors would also\nlike to acknowledge NOAA and Atmospheric Brown Cloud project\nfor support of the Trinidad Head and Kathmandu measurements.\n\nPublished - Adhikary2010p7381Atmos_Chem_Phys.pdf
", "abstract": "The Sulfur Transport and dEposition Model (STEM) is applied to the analysis of observations obtained during the Intercontinental Chemical Transport Experiment-Phase B (INTEX-B), conducted over the eastern Pacific Ocean during spring 2006. Predicted trace gas and aerosol distributions over the Pacific are presented and discussed in terms of transport and source region contributions. Trace species distributions show a strong west (high) to east (low) gradient, with the bulk of the pollutant transport over the central Pacific occurring between similar to 20 degrees N and 50 degrees N in the 2-6 km altitude range. These distributions are evaluated in the eastern Pacific by comparison with the NASA DC-8 and NSF/NCAR C-130 airborne measurements along with observations from the Mt. Bachelor (MBO) surface site. Thirty different meteorological, trace gas and aerosol parameters are compared. In general the meteorological fields are better predicted than gas phase species, which in turn are better predicted than aerosol quantities. PAN is found to be significantly overpredicted over the eastern Pacific, which is attributed to uncertainties in the chemical reaction mechanisms used in current atmospheric chemistry models in general and to the specifically high PAN production in the SAPRC-99 mechanism used in the regional model. A systematic underprediction of the elevated sulfate layer in the eastern Pacific observed by the C-130 is another issue that is identified and discussed. Results from source region tagged CO simulations are used to estimate how the different source regions around the Pacific contribute to the trace gas species distributions. During this period the largest contributions were from China and from fires in South/Southeast and North Asia. For the C-130 flights, which operated off the coast of the Northwest US, the regional CO contributions range as follows: China (35%), South/Southeast Asia fires (35%), North America anthropogenic (20%), and North Asia fires (10%). The transport of pollution into the western US is studied at MBO and a variety of events with elevated Asian dust, and periods with contributions from China and fires from both Asia and North America are discussed. The role of heterogeneous chemistry on the composition over the eastern Pacific is also studied. The impacts of heterogeneous reactions at specific times can be significant, increasing sulfate and nitrate aerosol production and reducing gas phase nitric acid levels appreciably (~50%).", "date": "2010-03-01", "date_type": "published", "publication": "Atmospheric Chemistry and Physics", "volume": "10", "number": "5", "publisher": "European Geosciences Union", "pagerange": "2091-2115", "id_number": "CaltechAUTHORS:20100416-094948497", "issn": "1680-7316", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20100416-094948497", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NNG04GC58G" }, { "agency": "NSF", "grant_number": "ATM-0613124" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/acp-10-2091-2010", "primary_object": { "basename": "Adhikary2010p7381Atmos_Chem_Phys.pdf", "url": "https://authors.library.caltech.edu/records/ezpwe-14w58/files/Adhikary2010p7381Atmos_Chem_Phys.pdf" }, "resource_type": "article", "pub_year": "2010", "author_list": "Adhikari, B.; Carmichael, G. R.; et el." }, { "id": "https://authors.library.caltech.edu/records/vh4qs-t9t59", "eprint_id": 17601, "eprint_status": "archive", "datestamp": "2023-08-22 00:52:07", "lastmod": "2023-10-20 00:03:05", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Paulot-F", "name": { "family": "Paulot", "given": "Fabien" }, "orcid": "0000-0001-7534-4922" }, { "id": "Crounse-J-D", "name": { "family": "Crounse", "given": "John D." }, "orcid": "0000-0001-5443-729X" }, { "id": "Kjaergaard-H-G", "name": { "family": "Kjaergaard", "given": "Henrik G." }, "orcid": "0000-0002-7275-8297" }, { "id": "K\u00fcrten-A", "name": { "family": "K\u00fcrten", "given": "Andreas" }, "orcid": "0000-0002-8955-4450" }, { "id": "St-Clair-J-M", "name": { "family": "St. Clair", "given": "Jason M." }, "orcid": "0000-0002-9367-5749" }, { "id": "Seinfeld-J-H", "name": { "family": "Seinfeld", "given": "John H." }, "orcid": "0000-0003-1344-4068" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "Response to Comment on \"Unexpected Epoxide Formation in the Gas-Phase Photooxidation of Isoprene\"", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 2010 American Association for the Advancement of Science.\nReceived 9 September 2009.\nAccepted 11 January 2010.", "abstract": "Claeys questions whether gaseous epoxydiol is formed from the oxidation of isoprene and whether it is relevant to the formation of isoprene-derived secondary organic aerosol (iSOA). We argue that the alternative mechanism she proposes for iSOA applies primarily to chamber studies with high isoprene and is not as important in the atmosphere, where isoprene concentrations are much lower.", "date": "2010-02-05", "date_type": "published", "publication": "Science", "volume": "327", "number": "5966", "publisher": "American Association for the Advancement of Science", "pagerange": "644", "id_number": "CaltechAUTHORS:20100225-165528156", "issn": "0036-8075", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20100225-165528156", "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.1181689", "resource_type": "article", "pub_year": "2010", "author_list": "Paulot, Fabien; Crounse, John D.; et el." }, { "id": "https://authors.library.caltech.edu/records/q04wx-g1e86", "eprint_id": 17339, "eprint_status": "archive", "datestamp": "2023-08-19 01:28:24", "lastmod": "2023-10-19 23:47:17", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Kautzman-K", "name": { "family": "Kautzman", "given": "K." } }, { "id": "Surratt-Jason-D", "name": { "family": "Surratt", "given": "J. D." }, "orcid": "0000-0002-6833-1450" }, { "id": "Chan-Man-Nin", "name": { "family": "Chan", "given": "M. N." }, "orcid": "0000-0002-2384-2695" }, { "id": "Chan-Arthur-W-H", "name": { "family": "Chan", "given": "A. W. H." }, "orcid": "0000-0001-7392-4237" }, { "id": "Hersey-Scott-P", "name": { "family": "Hersey", "given": "S. P." } }, { "id": "Chhabra-Puneet-S", "name": { "family": "Chhabra", "given": "P. S." } }, { "id": "Dalleska-Nathan-F", "name": { "family": "Dalleska", "given": "N. F." }, "orcid": "0000-0002-2059-1587" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Flagan-R-C", "name": { "family": "Flagan", "given": "R. C." }, "orcid": "0000-0001-5690-770X" }, { "id": "Seinfeld-J-H", "name": { "family": "Seinfeld", "given": "J. H." }, "orcid": "0000-0003-1344-4068" } ] }, "title": "Chemical Composition of Gas- and Aerosol-Phase Products from the Photooxidation of Naphthalene", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2009 American Chemical Society.\n\nReceived: September 3, 2009; Revised Manuscript Received: October 15, 2009. Publication Date (Web): November 11, 2009. \n\nThis research was funded by the Office of Science (BER), US Department of Energy Grant No. DE-FG02-05ER63983, US Environmental Protection Agency STAR Research Assistance Agreement No. RD-83374901 and US National Science Foundation grant ATM-0432377. The Electronic Power Research Institute provided support for the SEARCH network field samples. The GC/TOF and CIMS instruments used in this study were purchased as part of a major research instrumentation grant from the National Science Foundation (ATM-0619783). Assembly and testing of the CIMS instrument was supported by the Davidow Discovery Fund. The Waters UPLC/(-)ESI-TOFMS (LCT Premier XT TOFMS) was purchased in 2006 with a grant from the National Science Foundation, Chemistry Research Instrumentation and Facilities Program (CHE-0541745). We thank J. Stockdill for synthesis of 2-formylcinnamaldehyde. We would also like to thank E. S. Edgerton of Atmospheric Research & Analysis (ARA), Inc., for providing the high-volume filter sampler, as well as providing detailed information on its operation procedures, used in the sampling of fine aerosols during PACO. This publication has not been formally reviewed by the EPA. The views expressed in this document are solely those of the authors and EPA does not endorse any products mentioned in this publication.\n\nSupplemental Material - jp908530s_si_001.pdf
", "abstract": "The current work focuses on the detailed evolution of the chemical composition of both the gas- and aerosol-phase constituents produced from the OH-initiated photooxidation of naphthalene under low- and high-NO\u2093 conditions. Under high-NO\u2093 conditions ring-opening products are the primary gas-phase products, suggesting that the mechanism involves dissociation of alkoxy radicals (RO) formed through an RO\u2082 + NO pathway, or a bicyclic peroxy mechanism. In contrast to the high-NO\u2093 chemistry, ring-retaining compounds appear to dominate the low-NO\u2093 gas-phase products owing to the RO\u2082 + HO\u2082 pathway. We are able to chemically characterize 53\u221268% of the secondary organic aerosol (SOA) mass. Atomic oxygen-to-carbon (O/C), hydrogen-to-carbon (H/C), and nitrogen-to-carbon (N/C) ratios measured in bulk samples by high-resolution electrospray ionization time-of-flight mass spectrometry (HR-ESI-TOFMS) are the same as the ratios observed with online high-resolution time-of-flight aerosol mass spectrometry (HR-ToF-AMS), suggesting that the chemical compositions and oxidation levels found in the chemically-characterized fraction of the particle phase are representative of the bulk aerosol. Oligomers, organosulfates (R-OSO\u2083), and other high-molecular-weight (MW) products are not observed in either the low- or high-NO\u2093 SOA; however, in the presence of neutral ammonium sulfate seed aerosol, an organic sulfonic acid (R-SO\u2083), characterized as hydroxybenzene sulfonic acid, is observed in naphthalene SOA produced under both high- and low-NO\u2093 conditions. Acidic compounds and organic peroxides are found to account for a large fraction of the chemically characterized high- and low-NO\u2093 SOA. We propose that the major gas- and aerosol-phase products observed are generated through the formation and further reaction of 2-formylcinnamaldehyde or a bicyclic peroxy intermediate. The chemical similarity between the laboratory SOA and ambient aerosol collected from Birmingham, Alabama (AL) and Pasadena, California (CA) confirm the importance of PAH oxidation in the formation of aerosol within the urban atmosphere.", "date": "2010-01-21", "date_type": "published", "publication": "Journal of Physical Chemistry A", "volume": "114", "number": "2", "publisher": "American Chemical Society", "pagerange": "913-934", "id_number": "CaltechAUTHORS:20100128-134602813", "issn": "1089-5639", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20100128-134602813", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-FG02-05ER63983" }, { "agency": "Environmental Protection Agency (EPA)", "grant_number": "RD-83374901" }, { "agency": "NSF", "grant_number": "ATM-0432377" }, { "agency": "Electric Power Research Institute (EPRI)" }, { "agency": "NSF", "grant_number": "ATM-0619783" }, { "agency": "Davidow Discovery Fund" }, { "agency": "NSF", "grant_number": "CHE-0541745" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1021/jp908530s", "primary_object": { "basename": "jp908530s_si_001.pdf", "url": "https://authors.library.caltech.edu/records/q04wx-g1e86/files/jp908530s_si_001.pdf" }, "resource_type": "article", "pub_year": "2010", "author_list": "Kautzman, K.; Surratt, J. D.; et el." }, { "id": "https://authors.library.caltech.edu/records/4hd55-n8940", "eprint_id": 17604, "eprint_status": "archive", "datestamp": "2023-08-22 00:48:45", "lastmod": "2023-10-20 00:03:16", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Notholt-J", "name": { "family": "Notholt", "given": "J." } }, { "id": "Toon-G-C", "name": { "family": "Toon", "given": "G. C." }, "orcid": "0000-0003-4174-7541" }, { "id": "Fueglistaler-S", "name": { "family": "Fueglistaler", "given": "S." } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Irion-F-W", "name": { "family": "Irion", "given": "F. W." } }, { "id": "McCarthy-M", "name": { "family": "McCarthy", "given": "M." } }, { "id": "Scharringhausen-M", "name": { "family": "Scharringhausen", "given": "M." } }, { "id": "Rhee-T-Siek", "name": { "family": "Rhee", "given": "T. Siek" } }, { "id": "Klenb\u00f6hl-A", "name": { "family": "Kleinb\u00f6hl", "given": "A." } }, { "id": "Velazco-V", "name": { "family": "Velazco", "given": "V." } } ] }, "title": "Trend in ice moistening the stratosphere \u2013 constraints from isotope data of water and methane", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 Author(s) 2010. This work is distributed\nunder the Creative Commons Attribution 3.0 License.\nPublished by Copernicus Publications on behalf of the European Geosciences Union.\nReceived: 30 June 2009; published in Atmos. Chem. Phys. Discuss.: 12 August 2009; revised: 14 December 2009; accepted: 15 December 2009; published: 12 January 2010.\n\nThis research was financially supported by the EU-project SCOUT and by the national Helmholtz Association within the virtual institute PEP. We gratefully acknowledge Robert\nToth (JPL/NASA, Pasadena) for updates of the H2O and HDO\nspectral line list. We thank the Columbia Scientific Balloon Facility (CSBF) who launched the balloons from which the MkIV data were acquired and the financial support from NASA. We acknowledge Jean-Francois Blavier, Bhaswar Sen, and David Petterson of JPL for their various contributions to the JPL MkIV instrument.\n\nPublished - Notholt2010p7131Atmos_Chem_Phys.pdf
Supplemental Material - acp-10-201-2010-supplement.pdf
", "abstract": "Water plays a major role in the chemistry and radiative budget of the stratosphere. Air enters the stratosphere predominantly in the tropics, where the very low temperatures around the tropopause constrain water vapour mixing ratios to a few parts per million. Observations of stratospheric water vapour show a large positive long-term trend, which can not be explained by change in tropopause temperatures. Trends in the partitioning between vapour and ice of water entering the stratosphere have been suggested to resolve this conundrum. We present measurements of stratospheric H_(2)O, HDO, CH_4 and CH_(3)D in the period 1991\u20132007 to evaluate this hypothesis. Because of fractionation processes during phase changes, the hydrogen isotopic composition of H_(2)O is a sensitive indicator of changes in the partitioning of vapour and ice. We find that the seasonal variations of H_(2)O are mirrored in the variation of the ratio of HDO to H_(2)O with a slope of the correlation consistent with water entering the stratosphere mainly as vapour. The variability in the fractionation over the entire observation period is well explained by variations in H_(2)O. The isotopic data allow concluding that the trend in ice arising from particulate water is no more than (0.01\u00b10.13) ppmv/decade in the observation period. Our observations suggest that between 1991 and 2007 the contribution from changes in particulate water transported through the tropopause plays only a minor role in altering in the amount of water entering the stratosphere.", "date": "2010", "date_type": "published", "publication": "Atmospheric Chemistry and Physics", "volume": "10", "number": "1", "publisher": "European Geosciences Union", "pagerange": "201-207", "id_number": "CaltechAUTHORS:20100225-165718711", "issn": "1680-7316", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20100225-165718711", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "EU-project SCOUT" }, { "agency": "National Helmholtz Association" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/acp-10-201-2010", "primary_object": { "basename": "Notholt2010p7131Atmos_Chem_Phys.pdf", "url": "https://authors.library.caltech.edu/records/4hd55-n8940/files/Notholt2010p7131Atmos_Chem_Phys.pdf" }, "related_objects": [ { "basename": "acp-10-201-2010-supplement.pdf", "url": "https://authors.library.caltech.edu/records/4hd55-n8940/files/acp-10-201-2010-supplement.pdf" } ], "resource_type": "article", "pub_year": "2010", "author_list": "Notholt, J.; Toon, G. C.; et el." }, { "id": "https://authors.library.caltech.edu/records/94b7r-w2t18", "eprint_id": 16966, "eprint_status": "archive", "datestamp": "2023-08-22 00:45:40", "lastmod": "2023-10-19 22:41:53", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "McNaughton-C-S", "name": { "family": "McNaughton", "given": "C. S." } }, { "id": "Clarke-A-D", "name": { "family": "Clarke", "given": "A. D." } }, { "id": "Kapustin-V", "name": { "family": "Kapustin", "given": "V." } }, { "id": "Shinozuka-Yohei", "name": { "family": "Shinozuka", "given": "Y." } }, { "id": "Howell-S-G", "name": { "family": "Howell", "given": "S. G." } }, { "id": "Anderson-B-E", "name": { "family": "Anderson", "given": "B. E." } }, { "id": "Winstead-E", "name": { "family": "Winstead", "given": "E." } }, { "id": "Dibb-J-E", "name": { "family": "Dibb", "given": "J." }, "orcid": "0000-0003-3096-7709" }, { "id": "Scheuer-E", "name": { "family": "Scheuer", "given": "E." } }, { "id": "Cohen-R-C", "name": { "family": "Cohen", "given": "R. C." }, "orcid": "0000-0001-6617-7691" }, { "id": "Wooldridge-P", "name": { "family": "Wooldridge", "given": "P." } }, { "id": "Perring-A", "name": { "family": "Perring", "given": "A." } }, { "id": "Huey-L-G", "name": { "family": "Huey", "given": "L G." }, "orcid": "0000-0002-0518-7690" }, { "id": "Kim-S", "name": { "family": "Kim", "given": "S." } }, { "id": "Jimenez-J-L", "name": { "family": "Jimenez", "given": "J. L." }, "orcid": "0000-0001-6203-1847" }, { "id": "Dunlea-E-J", "name": { "family": "Dunlea", "given": "E. J." } }, { "id": "DeCarlo-P-F", "name": { "family": "DeCarlo", "given": "P. F." } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Crounse-J-D", "name": { "family": "Crounse", "given": "J. D." }, "orcid": "0000-0001-5443-729X" }, { "id": "Weinheimer-A-J", "name": { "family": "Weinheimer", "given": "A. J." }, "orcid": "0000-0001-6175-8286" }, { "id": "Flocke-F-M", "name": { "family": "Flocke", "given": "F." } } ] }, "title": "Observations of heterogeneous reactions between Asian pollution and mineral dust over the Eastern North Pacific during INTEX-B", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 Author(s) 2009. This work is distributed\nunder the Creative Commons Attribution 3.0 License.\nPublished by Copernicus Publications on behalf of the European Geosciences Union.\nReceived: 19 February 2009; Published in Atmos. Chem. Phys. Discuss.: 31 March 2009; revised: 11 September 2009; accepted: 15 September 2009; published: 3 November 2009.\n\nWe gratefully acknowledge M. Avery for providing DC-8 measurements of O3. We appreciate the use of Barry Huebert's MLO data, which was collected under NSF grants\nATM01-04532 and ATM04-41274. This research was funded under\nNASA Grant: NNG06GA90G and NSF Grant: ATM05-11521.\nED, PFD, and JLJ were supported by NASA grant NNG06GB03G\nand NSF grant ATM-0513116. We would also like to acknowledge\nJ. Kelly, R. Sullivan and C. Zender for their constructive reviews of the original manuscript. This is SOEST publication number 7622.\n\nEdited by: H. Singh.\n\nPublished - McNaughton2009p6469Atmos_Chem_Phys.pdf
", "abstract": "In-situ airborne measurements of trace gases, aerosol size distributions, chemistry and optical properties were conducted over Mexico and the Eastern North Pacific during MILAGRO and INTEX-B. Heterogeneous reactions between secondary aerosol precursor gases and mineral dust lead to sequestration of sulfur, nitrogen and chlorine in the supermicrometer particulate size range. \n\nSimultaneous measurements of aerosol size distributions and weak-acid soluble calcium result in an estimate of 11 wt% of CaCO_3 for Asian dust. During transport across the North Pacific, ~5\u201330% of the CaCO_3 is converted to CaSO_4 or Ca(NO_3)_2 with an additional ~4% consumed through reactions with HCl. The 1996 to 2008 record from the Mauna Loa Observatory confirm these findings, indicating that, on average, 19% of the CaCO_3 has reacted to form CaSO_4 and 7% has reacted to form Ca(NO_3)_2 and ~2% has reacted with HCl. In the nitrogen-oxide rich boundary layer near Mexico City up to 30% of the CaCO_3 has reacted to form Ca(NO_3)_2 while an additional 8% has reacted with HCl. \n\nThese heterogeneous reactions can result in a ~3% increase in dust solubility which has an insignificant effect on their optical properties compared to their variability in-situ. However, competition between supermicrometer dust and submicrometer primary aerosol for condensing secondary aerosol species led to a 25% smaller number median diameter for the accumulation mode aerosol. A 10\u201325% reduction of accumulation mode number median diameter results in a 30\u201370% reduction in submicrometer light scattering at relative humidities in the 80\u201395% range. At 80% RH submicrometer light scattering is only reduced ~3% due to a higher mass fraction of hydrophobic refractory components in the dust-affected accumulation mode aerosol. Thus reducing the geometric mean diameter of the submicrometer aerosol has a much larger effect on aerosol optical properties than changes to the hygroscopic:hydrophobic mass fractions of the accumulation mode aerosol. \n\nIn the presence of dust, nitric acid concentrations are reduced to <50% of total nitrate (nitric acid plus particulate nitrate). NO_y as a fraction of total nitrogen (NO_y plus particulate nitrate), is reduced from >85% to 60\u201380% in the presence of dust. These observations support previous model studies which predict irreversible sequestration of reactive nitrogen species through heterogeneous reactions with mineral dust during long-range transport.", "date": "2009-11-03", "date_type": "published", "publication": "Atmospheric Chemistry and Physics", "volume": "9", "number": "21", "publisher": "European Geosciences Union", "pagerange": "8283-8308", "id_number": "CaltechAUTHORS:20091211-141548258", "issn": "1680-7316", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20091211-141548258", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "ATM01-04532" }, { "agency": "NSF", "grant_number": "ATM04-41274" }, { "agency": "NASA", "grant_number": "NNG06GA90G" }, { "agency": "NSF", "grant_number": "ATM05-11521" }, { "agency": "NASA", "grant_number": "NNG06GB03G" }, { "agency": "NSF", "grant_number": "ATM-0513116" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/acp-9-8283-2009", "primary_object": { "basename": "McNaughton2009p6469Atmos_Chem_Phys.pdf", "url": "https://authors.library.caltech.edu/records/94b7r-w2t18/files/McNaughton2009p6469Atmos_Chem_Phys.pdf" }, "resource_type": "article", "pub_year": "2009", "author_list": "McNaughton, C. S.; Clarke, A. D.; et el." }, { "id": "https://authors.library.caltech.edu/records/an3jc-rpt82", "eprint_id": 15339, "eprint_status": "archive", "datestamp": "2023-08-22 00:39:13", "lastmod": "2023-10-18 21:41:38", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Yokelson-R-J", "name": { "family": "Yokelson", "given": "R. J." }, "orcid": "0000-0002-8415-6808" }, { "id": "Crounse-J-D", "name": { "family": "Crounse", "given": "J. D." }, "orcid": "0000-0001-5443-729X" }, { "id": "DeCarlo-P-F", "name": { "family": "DeCarlo", "given": "P. F." } }, { "id": "Karl-T", "name": { "family": "Karl", "given": "T." } }, { "id": "Urbanski-S", "name": { "family": "Urbanski", "given": "S." } }, { "id": "Atlas-E-L", "name": { "family": "Atlas", "given": "E." }, "orcid": "0000-0003-3847-5346" }, { "id": "Campos-T", "name": { "family": "Campos", "given": "T." } }, { "id": "Shinozuka-Yohei", "name": { "family": "Shinozuka", "given": "Y." } }, { "id": "Kapustin-V", "name": { "family": "Kapustin", "given": "V." } }, { "id": "Clarke-A-D", "name": { "family": "Clarke", "given": "A. D." } }, { "id": "Weinheimer-A-J", "name": { "family": "Weinheimer", "given": "A." }, "orcid": "0000-0001-6175-8286" }, { "id": "Knapp-D-J", "name": { "family": "Knapp", "given": "D. J." } }, { "id": "Montzka-D-D", "name": { "family": "Montzka", "given": "D. D." } }, { "id": "Holloway-J-S", "name": { "family": "Holloway", "given": "J." } }, { "id": "Weibring-P", "name": { "family": "Weibring", "given": "P." } }, { "id": "Flocke-F-M", "name": { "family": "Flocke", "given": "F." } }, { "id": "Zheng-W", "name": { "family": "Zheng", "given": "W." } }, { "id": "Toohey-D", "name": { "family": "Toohey", "given": "D." } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Wiedinmyer-C", "name": { "family": "Wiedinmyer", "given": "C." } }, { "id": "Mauldin-L", "name": { "family": "Mauldin", "given": "L." } }, { "id": "Fried-A", "name": { "family": "Fried", "given": "A." } }, { "id": "Richter-D", "name": { "family": "Richter", "given": "D." } }, { "id": "Walega-J", "name": { "family": "Walega", "given": "J." } }, { "id": "Jimenez-J-L", "name": { "family": "Jimenez", "given": "J. L." }, "orcid": "0000-0001-6203-1847" }, { "id": "Adachi-K", "name": { "family": "Adachi", "given": "K." } }, { "id": "Buseck-P-R", "name": { "family": "Buseck", "given": "P. R." } }, { "id": "Hall-S-R", "name": { "family": "Hall", "given": "S. R." }, "orcid": "0000-0002-2060-7112" }, { "id": "Shetter-R", "name": { "family": "Shetter", "given": "R." } } ] }, "title": "Emissions from biomass burning in the Yucatan", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 Author(s) 2009. This work is distributed under the Creative Commons Attribution 3.0 License. \n\nReceived: 2 October 2008 \u2013 Published in Atmos. Chem. Phys. Discuss.: 9 January 2009. Revised: 30 June 2009 \u2013 Accepted: 28 July 2009 \u2013 Published: 12 August 2009.\n\nThe authors thank Eric Hintsa and Anne-Marie Schmoltner of NSF for supplemental funding for ASU and U Miami, and travel funds for CU to conduct measurements on the Twin Otter. We thank the Twin Otter and C-130 pilots. Thanks go to Sasha Madronich, Luisa Molina, and Jose Meitin for coordinating the overall MILAGRO campaign. The University of Montana and the Twin Otter were supported mostly by NSF grant ATM-0513055. Yokelson was also supported by the Strategic Environmental Research and Development Program (SERDP) of DoD. Support for the USFS and Twin Otter was provided by the NASA North American Carbon Plan (NNHO5AA86I). P. F. DeCarlo and J. L. Jimenez were supported by NSF ATM-0513116 and ATM-0449815, NASA NNG06GB03G, and EPA Graduate Fellowship FP-91650801. Participation by Arizona State University was supported by NSF grant ATM-0531926. We gratefully acknowledge the use of TEMs within the LeRoy Eyring Center for Solid State Science at Arizona State University. Support to the University of Miami was provided by NSF (ATM 0511820). X. Zhu and L. Pope provided excellent technical support for the canister trace gas analyses. Support for operation of the Caltech CIMS instrument was provided by NASA (NNG04GA59G) and by EPA-STAR support for J. Crounse. The C-130 forward looking video was provided by NCAR/EOL under sponsorship of the National Science Foundation. http://data.eol.ucar.edu/.\n\nPublished - Yokelson2009p5714Atmos_Chem_Phys.pdf
", "abstract": "In March 2006 two instrumented aircraft made the first detailed field measurements of biomass burning (BB) emissions in the Northern Hemisphere tropics as part of the MILAGRO project. The aircraft were the National Center for Atmospheric Research C-130 and a University of Montana/US Forest Service Twin Otter. The initial emissions of up to 49 trace gas or particle species were measured from 20 deforestation and crop residue fires on the Yucatan peninsula. This included two trace gases useful as indicators of BB (HCN and acetonitrile) and several rarely, or never before, measured species: OH, peroxyacetic acid, propanoic acid, hydrogen peroxide, methane sulfonic acid, and sulfuric acid. Crop residue fires emitted more organic acids and ammonia than deforestation fires, but the emissions from the main fire types were otherwise fairly similar. The Yucatan fires emitted unusually high amounts of SO2 and particle chloride, likely due to a strong marine influence on this peninsula. As smoke from one fire aged, the ratio \u0394O3/\u0394CO increased to ~15% in <~1 h similar to the fast net production of O_3 in BB plumes observed earlier in Africa. The rapid change in O_3 occurs at a finer spatial scale than is employed in global models and is also faster than predicted by micro-scale models. Fast increases in PAN, H_2O_2, and two organic acids were also observed. The amount of secondary organic acid is larger than the amount of known precursors. Rapid secondary formation of organic and inorganic aerosol was observed with the ratio \u0394PM2.5/\u0394CO more than doubling in ~1.4\u00b10.7 h. The OH measurements revealed high initial levels (>1\u00d710^7 molecules/cm^3) that were likely caused in part by high initial HONO (~10% of NO_y). Thus, more research is needed to understand critical post emission processes for the second-largest trace gas source on Earth. It is estimated that ~44 Tg of biomass burned in the Yucatan in the spring of 2006. Mexican BB (including Yucatan BB) and urban emissions from the Mexico City area can both influence the March-May air quality in much of Mexico and the US.", "date": "2009-08-12", "date_type": "published", "publication": "Atmospheric Chemistry and Physics", "volume": "9", "number": "15", "publisher": "European Geosciences Union", "pagerange": "5785-5812", "id_number": "CaltechAUTHORS:20090826-112856733", "issn": "1680-7316", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20090826-112856733", "rights": "This work is distributed under the Creative Commons Attribution 3.0 License.", "funders": { "items": [ { "agency": "NSF", "grant_number": "ATM-0513055" }, { "agency": "Department of Defense" }, { "agency": "NASA", "grant_number": "NNHO5AA86I" }, { "agency": "NSF", "grant_number": "ATM-0513116" }, { "agency": "NSF", "grant_number": "ATM-0449815" }, { "agency": "NASA", "grant_number": "NNG06GB03G" }, { "agency": "Environmental Protection Agency (EPA)", "grant_number": "FP-91650801" }, { "agency": "NSF", "grant_number": "ATM-0531926" }, { "agency": "NSF", "grant_number": "ATM 0511820" }, { "agency": "NASA", "grant_number": "NNG04GA59G" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/acp-9-5785-2009", "primary_object": { "basename": "Yokelson2009p5714Atmos_Chem_Phys.pdf", "url": "https://authors.library.caltech.edu/records/an3jc-rpt82/files/Yokelson2009p5714Atmos_Chem_Phys.pdf" }, "resource_type": "article", "pub_year": "2009", "author_list": "Yokelson, R. J.; Crounse, J. D.; et el." }, { "id": "https://authors.library.caltech.edu/records/yfrgd-8hw59", "eprint_id": 15078, "eprint_status": "archive", "datestamp": "2023-08-22 00:39:06", "lastmod": "2023-10-18 20:29:39", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Paulot-F", "name": { "family": "Paulot", "given": "Fabien" }, "orcid": "0000-0001-7534-4922" }, { "id": "Crounse-J-D", "name": { "family": "Crounse", "given": "John D." }, "orcid": "0000-0001-5443-729X" }, { "id": "Kjaergaard-H-G", "name": { "family": "Kjaergaard", "given": "Henrik G." }, "orcid": "0000-0002-7275-8297" }, { "id": "Kuerten-A", "name": { "family": "Kuerten", "given": "Adreas" } }, { "id": "St-Clair-J-M", "name": { "family": "St. Clair", "given": "Jason M." }, "orcid": "0000-0002-9367-5749" }, { "id": "Seinfeld-J-H", "name": { "family": "Seinfeld", "given": "John H." }, "orcid": "0000-0003-1344-4068" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "Unexpected Epoxide Formation in the Gas-Phase Photooxidation of Isoprene", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2009 American Association for the Advancement of Science. \n\nReceived for publication 2 March 2009. Accepted for publication 24 June 2009. \n\nWe thank X. Levine, H. O. T. Pye, and the Harvard GEOS CHEM team (Daniel J. Jacob, principal investigator) for their help in setting up the GEOS-CHEM model; A. J. Kwan, A. W. Chan, P. S. Chhabra, and N. Eddingsaas for experimental assistance; J. D. Surratt for providing the speciation of the SOA resulting from BEPOX reactive uptake; and J. Lane, I. Maxwell-Cameron, and S. J\u00f8rgensen for helpful discussions regarding the quantum calculations. F.P. was partially supported by the William and Sonya Davidow fellowship. J.D.C. thanks the EPA Science to Achieve Results (STAR) Fellowship Program (FP916334012) for providing partial support. The mass spectrometer used in this study was purchased as part of a major research instrumentation grant from the National Science Foundation (ATM-0619783). Assembly and testing of the CIMS instrument was supported by the Davidow Discovery Fund. The numerical simulations for this research were performed on Caltech's Division of Geological and Planetary Sciences Dell Cluster. This work was supported by the Office of Science (Biological and Environmental Research), U.S. Department of Energy grant DE-FG02-05ER63983, U.S. Environmental Protection Agency STAR agreement RD-833749, and the Marsden Fund administrated by the Royal Society of New Zealand. The TC4 and ARCTAS campaigns were supported by NASA grants NNX07AL33G and NNX08AD29G. This work has not been formally reviewed by the EPA. The views expressed in this document are solely those of the authors, and the EPA does not endorse any products or commercial services mentioned in this publication.\n\nSupporting Online Material\nwww.sciencemag.org/cgi/content/full/325/5941/730/DC1\nMaterials and Methods\nFigs. S1 to S9\nTables S1 to S9\nReferences\n\nSupplemental Material - 1.pdf
", "abstract": "Emissions of nonmethane hydrocarbon compounds to the atmosphere from the biosphere exceed those from anthropogenic activity. Isoprene, a five-carbon diene, contributes more than 40% of these emissions. Once emitted to the atmosphere, isoprene is rapidly oxidized by the hydroxyl radical OH. We report here that under pristine conditions isoprene is oxidized primarily to hydroxyhydroperoxides. Further oxidation of these hydroxyhydroperoxides by OH leads efficiently to the formation of dihydroxyepoxides and OH reformation. Global simulations show an enormous flux -\u2014 nearly 100 teragrams of carbon per year -\u2014 of these epoxides to the atmosphere. The discovery of these highly soluble epoxides provides a missing link tying the gas-phase degradation of isoprene to the observed formation of organic aerosols.", "date": "2009-08-07", "date_type": "published", "publication": "Science", "volume": "325", "number": "5941", "publisher": "American Association for the Advancement of Science", "pagerange": "730-733", "id_number": "CaltechAUTHORS:20090817-144809010", "issn": "0036-8075", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20090817-144809010", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Caltech" }, { "agency": "Environmental Protection Agency (EPA)", "grant_number": "FP916334012" }, { "agency": "NSF", "grant_number": "ATM-0619783" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-FG02-05ER63983" }, { "agency": "Environmental Protection Agency (EPA)", "grant_number": "RD-833749" }, { "agency": "Royal Society of New Zealand" }, { "agency": "NASA", "grant_number": "NNX07AL33G" }, { "agency": "NASA", "grant_number": "NNX08AD29G" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1126/science.1172910", "primary_object": { "basename": "1.pdf", "url": "https://authors.library.caltech.edu/records/yfrgd-8hw59/files/1.pdf" }, "resource_type": "article", "pub_year": "2009", "author_list": "Paulot, Fabien; Crounse, John D.; et el." }, { "id": "https://authors.library.caltech.edu/records/qf86h-ym337", "eprint_id": 15329, "eprint_status": "archive", "datestamp": "2023-08-22 00:38:56", "lastmod": "2023-10-18 21:40:35", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Wunch-D", "name": { "family": "Wunch", "given": "D." }, "orcid": "0000-0002-4924-0377" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Toon-G-C", "name": { "family": "Toon", "given": "G. C." }, "orcid": "0000-0003-4174-7541" }, { "id": "Keppel-Aleks-G", "name": { "family": "Keppel-Aleks", "given": "G." } }, { "id": "Yavin-Y-G", "name": { "family": "Yavin", "given": "Y. G." } } ] }, "title": "Emissions of greenhouse gases from a North American megacity", "ispublished": "pub", "full_text_status": "public", "keywords": "greenhouse gas; urban; methane", "note": "\u00a9 2009. American Geophysical Union. \n\nReceived 29 June 2009; accepted 9 July 2009; published 6 August 2009. \n\nThe authors thank Alan Kwan, Kathleen Spencer, Amy Townsend-Small, Charles E. Miller and Ying K. Hsu for helpful discussions, Jean-Fran\u00e7ois L. Blavier for invaluable technical assistance and two anonymous reviewers for insightful comments. The authors gratefully acknowledge the NOAA Air Resources Laboratory (ARL) for the provision of the READY website (http://www.arl.noaa.gov/ready.html) used in this publication [Draxler and Rolph, 2003; Rolph, 2003]. Part of this research was conducted at the Jet Propulsion Laboratory, California Institute of Technology, under contract with NASA. Support for this work is from the NASA Carbon Cycle Program grant NNX08AI86G and from the NASA OCO Project grant NAS7-03001.\n\nPublished - Wunch2009p5706Geophys_Res_Lett.pdf
", "abstract": "Atmospheric column abundances of carbon dioxide (CO_2), carbon monoxide (CO), methane (CH_4) and nitrous oxide (N_2O) have been measured above the South Coast air basin (SCB), a densely populated urban region of Southern California, USA, which includes Los Angeles and the surrounding suburbs. Large diurnal variations in CO and CH_4 are observed which correlate well with those in CO_2. Weaker correlations are seen between N_2O and CO_2, with large uncertainties. We compute yearly SCB emissions of CO and CH_4 to be 1.4 \u00b1 0.3 Tg CO and 0.6 \u00b1 0.1 Tg CH_4. We compare our calculated emissions to the California Air Resources Board (CARB) and the Emission Database for Global Atmospheric Research (EDGAR) estimates. Our measurements confirm that urban emissions are a significant source of CH_4 and in fact may be substantially higher than currently estimated. If our emissions are typical of other urban centers, these findings suggest that urban emissions could contribute 7\u201315% to the global anthropogenic budget of methane.", "date": "2009-08-06", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "36", "number": "15", "publisher": "American Geophysical Union", "pagerange": "L15810", "id_number": "CaltechAUTHORS:20090826-112853465", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20090826-112853465", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NNX08AI86G" }, { "agency": "NASA", "grant_number": "NAS7-03001" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2009GL039825", "primary_object": { "basename": "Wunch2009p5706Geophys_Res_Lett.pdf", "url": "https://authors.library.caltech.edu/records/qf86h-ym337/files/Wunch2009p5706Geophys_Res_Lett.pdf" }, "resource_type": "article", "pub_year": "2009", "author_list": "Wunch, D.; Wennberg, P. O.; et el." }, { "id": "https://authors.library.caltech.edu/records/64jd9-3n377", "eprint_id": 15128, "eprint_status": "archive", "datestamp": "2023-08-22 00:37:49", "lastmod": "2023-10-18 21:00:30", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Crounse-J-D", "name": { "family": "Crounse", "given": "J. D." }, "orcid": "0000-0001-5443-729X" }, { "id": "DeCarlo-P-F", "name": { "family": "DeCarlo", "given": "P. F." } }, { "id": "Blake-D-R", "name": { "family": "Blake", "given": "D. R." } }, { "id": "Emmons-L-K", "name": { "family": "Emmons", "given": "L. K." } }, { "id": "Campos-T-L", "name": { "family": "Campos", "given": "T. L." } }, { "id": "Apel-E-C", "name": { "family": "Apel", "given": "E. C." } }, { "id": "Clarke-A-D", "name": { "family": "Clarke", "given": "A. D." } }, { "id": "Weinheimer-A-J", "name": { "family": "Weinheimer", "given": "A. J." }, "orcid": "0000-0001-6175-8286" }, { "id": "McCabe-D-C", "name": { "family": "McCabe", "given": "D. C." } }, { "id": "Yokelson-R-J", "name": { "family": "Yokelson", "given": "R. J." }, "orcid": "0000-0002-8415-6808" }, { "id": "Jimenez-J-L", "name": { "family": "Jimenez", "given": "J. L." }, "orcid": "0000-0001-6203-1847" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "Biomass burning and urban air pollution over the Central Mexican Plateau", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 Author(s) 2009. This work is distributed under the Creative Commons Attribution 3.0 License. \n\nReceived: 18 November 2008 \u2013 Published in Atmos. Chem. Phys. Discuss.: 28 January 2009. Revised: 12 May 2009 \u2013 Accepted: 9 July 2009 \u2013 Published: 24 July 2009. \n\nThe MIRAGE-mex campaign was a cooperative project of NASA and NSF. Funding for Caltech was provided through NASA (NAG: NNG06GB32B). We thank S. Madonich, F. Flocke, and NCAR's Research Aviation Facility (RAF) for mission design and support with instrument integration onto the aircraft. The National Center for Atmospheric Research is sponsored by the National Science Foundation. C. Wiedinmyer provided climatological fire data from the MODIS instrumentation. We thank J. Fast for comments on this work. We thank U. Steiner, J. Oliver, and N. Allen for technical support of the CIMS instruments whose development was generously supported by William and Sonja Davidow. J.D.C. and P.F.D. acknowledge support from the EPA-STAR Fellowship Program (FP916334012 and FP91650801). Funding for J.L.J. and P.D.F. was provided though NSF (ATM-0513116) and NASA grants (NNG06GB03G). D.R.B. acknowledges NSF's Atmospheric Chemistry Division (ACD) for support. This work has not been formally reviewed by the EPA. The views expressed in this document are solely those of the authors and the EPA does not endorse any products or commercial services mentioned in this publication.\n\nPublished - Crounse2009p5628Atmos_Chem_Phys.pdf
Supplemental Material - acp-9-4929-2009-supplement.pdf
", "abstract": "Observations during the 2006 dry season of highly elevated concentrations of cyanides in the atmosphere above Mexico City (MC) and the surrounding plains demonstrate that biomass burning (BB) significantly impacted air quality in the region. We find that during the period of our measurements, fires contribute more than half of the organic aerosol mass and submicron aerosol scattering, and one third of the enhancement in benzene, reactive nitrogen, and carbon monoxide in the outflow from the plateau. The combination of biomass burning and anthropogenic emissions will affect ozone chemistry in the MC outflow.", "date": "2009-07-24", "date_type": "published", "publication": "Atmospheric Chemistry and Physics", "volume": "9", "number": "14", "publisher": "European Geosciences Union", "pagerange": "4929-4944", "id_number": "CaltechAUTHORS:20090817-144820071", "issn": "1680-7316", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20090817-144820071", "rights": "This work is distributed under the Creative Commons Attribution 3.0 License.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NNG06GB32B" }, { "agency": "NSF", "grant_number": "ATM-0513116" }, { "agency": "Environmental Protection Agency (EPA)", "grant_number": "FP916334012" }, { "agency": "Environmental Protection Agency (EPA)", "grant_number": "FP91650801" }, { "agency": "NASA", "grant_number": "NNG06GB03G" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/acp-9-4929-2009", "primary_object": { "basename": "Crounse2009p5628Atmos_Chem_Phys.pdf", "url": "https://authors.library.caltech.edu/records/64jd9-3n377/files/Crounse2009p5628Atmos_Chem_Phys.pdf" }, "related_objects": [ { "basename": "acp-9-4929-2009-supplement.pdf", "url": "https://authors.library.caltech.edu/records/64jd9-3n377/files/acp-9-4929-2009-supplement.pdf" } ], "resource_type": "article", "pub_year": "2009", "author_list": "Crounse, J. D.; DeCarlo, P. F.; et el." }, { "id": "https://authors.library.caltech.edu/records/3151r-rys92", "eprint_id": 15035, "eprint_status": "archive", "datestamp": "2023-08-20 02:13:35", "lastmod": "2023-10-18 20:28:20", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Chan-Arthur-W-H", "name": { "family": "Chan", "given": "Arthur W. H." }, "orcid": "0000-0001-7392-4237" }, { "id": "Galloway-Melissa-M", "name": { "family": "Galloway", "given": "Melissa M." }, "orcid": "0000-0002-8518-1888" }, { "id": "Kwan-Allan-J", "name": { "family": "Kwan", "given": "Allan J." } }, { "id": "Chhabra-Puneet-S", "name": { "family": "Chhabra", "given": "Puneet S." } }, { "id": "Keutsch-Frank-N", "name": { "family": "Keutsch", "given": "Frank N." }, "orcid": "0000-0002-1442-6200" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Flagan-R-C", "name": { "family": "Flagan", "given": "Richard C." }, "orcid": "0000-0001-5690-770X" }, { "id": "Seinfeld-J-H", "name": { "family": "Seinfeld", "given": "John H." }, "orcid": "0000-0003-1344-4068" } ] }, "title": "Photooxidation of 2-methyl-3-buten-2-ol (MBO) as a potential source of secondary organic aerosol", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 2009 American Chemical Society. \n\nReceived September 11, 2008. Revised manuscript received December 15, 2008. Accepted December 19, 2008. Publication Date (Web): January 29, 2009. \n\nThis research was funded by U.S. Department of Energy Biological and Environmental Research Program DE-FG02-05ER63983, U.S. Environmental Protection Agency STAR grant\nRD-83374901, and U.S. National Science Foundation grant\nATM-0432377. This work was also supported by the Camille\nand Henry Dreyfus Foundation and development of the\nMadison-LIP instrument was supported by the National Science\nFoundation, Division of Atmospheric Sciences, Atmospheric\nChemistry Program(grant 0724912),and the NDSEG-ARO.This\npublication has not been formally reviewed by the EPA. The\nviews expressed in this document are solely those of the authors and EPA does not endorse any products mentioned in this publication. We thank Henrik Kjaergaard for density functional theory calculations of the dipole moments and polarizabilities of various gas-phase species. \n\nThis article is part of the Particulate Matter and Human Health special issue.", "abstract": "2-Methyl-3-buten-2-ol (MBO) is an important biogenic hydrocarbon emitted in large quantities by pine forests. Atmospheric photooxidation of MBO is known to lead to oxygenated compounds, such as glycolaldehyde, which is the precursor to glyoxal. Recent studies have shown that the reactive uptake of glyoxal onto aqueous particles can lead to formation of secondary organic aerosol (SOA). In this work, MBO photooxidation under high- and low-NO\u2093 conditions was performed in dual laboratory chambers to quantify the yield of glyoxal and investigate the potential for SOA formation. The yields of glycolaldehyde and 2-hydroxy-2-methylpropanal (HMPR), fragmentation products of MBO photooxidation, were observed to be lower at lower NO\u2093 concentrations. Overall, the glyoxal yield from MBO photooxidation was 25% under high-NO\u2093 and 4% under low-NO\u2093 conditions. In the presence of wet ammonium sulfate seed and under high-NO\u2093 conditions, glyoxal uptake and SOA formation were not observed conclusively, due to relatively low (<30 ppb) glyoxal concentrations. Slight aerosol formation was observed under low-NO\u2093 and dry conditions, with aerosol mass yields on the order of 0.1%. The small amount of SOA was not related to glyoxal uptake, but is likely a result of reactions similar to those that generate isoprene SOA under low-NO\u2093 conditions. The difference in aerosol yields between MBO and isoprene photooxidation under low-NO\u2093 conditions is consistent with the difference in vapor pressures between triols (from MBO) and tetrols (from isoprene). Despite its structural similarity to isoprene, photooxidation of MBO is not expected to make a significant contribution to SOA formation.", "date": "2009-07-01", "date_type": "published", "publication": "Environmental Science and Technology", "volume": "43", "number": "13", "publisher": "American Chemical Society", "pagerange": "4647-4652", "id_number": "CaltechAUTHORS:20090814-113136745", "issn": "0013-936X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20090814-113136745", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-FG02-05ER63983" }, { "agency": "Environmental Protection Agency (EPA)", "grant_number": "RD-83374901" }, { "agency": "NSF", "grant_number": "ATM-0432377" }, { "agency": "Camille and Henry Dreyfus Foundation" }, { "agency": "NSF", "grant_number": "AGS-0724912" }, { "agency": "Army Research Office (ARO)" }, { "agency": "National Defense Science and Engineering Graduate (NDSEG) Fellowship" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1021/es802560w", "resource_type": "article", "pub_year": "2009", "author_list": "Chan, Arthur W. H.; Galloway, Melissa M.; et el." }, { "id": "https://authors.library.caltech.edu/records/fyc5d-pe383", "eprint_id": 15337, "eprint_status": "archive", "datestamp": "2023-08-22 00:34:56", "lastmod": "2023-10-18 21:41:12", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Spencer-K-M", "name": { "family": "Spencer", "given": "K. M." } }, { "id": "McCabe-D-C", "name": { "family": "McCabe", "given": "D. C." } }, { "id": "Crounse-J-D", "name": { "family": "Crounse", "given": "J. D." }, "orcid": "0000-0001-5443-729X" }, { "id": "Olson-J-R", "name": { "family": "Olson", "given": "J. R." } }, { "id": "Crawford-J-H", "name": { "family": "Crawford", "given": "J. H." } }, { "id": "Weinheimer-A-J", "name": { "family": "Weinheimer", "given": "A. J." }, "orcid": "0000-0001-6175-8286" }, { "id": "Knapp-D-J", "name": { "family": "Knapp", "given": "D. J." } }, { "id": "Montzka-D-D", "name": { "family": "Montzka", "given": "D. D." } }, { "id": "Cantrell-C-A", "name": { "family": "Cantrell", "given": "C. A." } }, { "id": "Hornbrook-R-S", "name": { "family": "Hornbrook", "given": "R. S." } }, { "id": "Mauldin-R-L", "name": { "family": "Mauldin", "given": "R. L." } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "Inferring ozone production in an urban atmosphere using measurements of peroxynitric acid", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 Author(s) 2009. This work is distributed under the Creative Commons Attribution 3.0 License. \n\nReceived: 1 December 2008 \u2013 Published in Atmos. Chem. Phys. Discuss.: 28 January 2009. Revised: 28 April 2009 \u2013 Accepted: 15 May 2009 \u2013 Published: 8 June 2009. \n\nThe authors wish to thank C. M. Roehl for synthesizing the peroxynitric acid for calibration. P. Weibring and A. Fried, D. R. Blake, and R. E. Shetter provided formaldehyde, whole air sample, and solar actinic flux measurements, respectively, which provided constrains for the photochemical box model. The authors also wish to thank the C-130 crew and support team. The HO2NO2 measurements and their interpretation was made possible with the financial support of NASA (NAG: NNG06GB32B). J. D. C. acknowledges support from the EPA-STAR Fellowship Program (FP916334012). This work has not been formally reviewed by the EPA. The views expressed in this document are solely those of the authors and the EPA does not endorse any products or commercial services mentioned in this publication.\n\nPublished - Spencer2009p5710Atmos_Chem_Phys.pdf
", "abstract": "Observations of peroxynitric acid (HO_2NO_2) obtained simultaneously with those of NO and NO_2 provide a sensitive measure of the ozone photochemical production rate. We illustrate this technique for constraining the ozone production rate with observations obtained from the NCAR C-130 aircraft platform during the Megacity Initiative: Local and Global Research Observations (MILAGRO) intensive in Mexico during the spring of 2006. Sensitive and selective measurements of HO_2NO_2 were made in situ using chemical ionization mass spectrometry (CIMS). Observations were compared to modeled HO_2NO_2 concentrations obtained from the NASA Langley highly-constrained photochemical time-dependent box model. The median observed-to-calculated ratio of HO_2NO_2 is 1.18. At NOx levels greater than 15 ppbv, the photochemical box model underpredicts observations with an observed-to-calculated ratio of HO_2NO_2 of 1.57. As a result, we find that at high NO_x, the ozone production rate calculated using measured HO_2NO_2 is faster than predicted using accepted photochemistry. Inclusion of an additional HO_x source from the reaction of excited state NO_2 with H_2O or reduction in the rate constant of the reaction of OH with NO_2 improves the agreement.", "date": "2009-06-08", "date_type": "published", "publication": "Atmospheric Chemistry and Physics", "volume": "9", "number": "11", "publisher": "European Geosciences Union", "pagerange": "3697-3707", "id_number": "CaltechAUTHORS:20090826-112856142", "issn": "1680-7316", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20090826-112856142", "rights": "This work is distributed under the Creative Commons Attribution 3.0 License.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NNG06GB32B" }, { "agency": "Environmental Protection Agency (EPA)", "grant_number": "FP916334012" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/acp-9-3697-2009", "primary_object": { "basename": "Spencer2009p5710Atmos_Chem_Phys.pdf", "url": "https://authors.library.caltech.edu/records/fyc5d-pe383/files/Spencer2009p5710Atmos_Chem_Phys.pdf" }, "resource_type": "article", "pub_year": "2009", "author_list": "Spencer, K. M.; McCabe, D. C.; et el." }, { "id": "https://authors.library.caltech.edu/records/6wwc8-gsg46", "eprint_id": 14696, "eprint_status": "archive", "datestamp": "2023-08-22 00:31:42", "lastmod": "2023-10-18 18:43:15", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Garden-A-L", "name": { "family": "Garden", "given": "Anna L." } }, { "id": "Paulot-F", "name": { "family": "Paulot", "given": "Fabien" }, "orcid": "0000-0001-7534-4922" }, { "id": "Crounse-J-D", "name": { "family": "Crounse", "given": "John D." }, "orcid": "0000-0001-5443-729X" }, { "id": "Maxwell-Cameron-I-J", "name": { "family": "Maxwell-Cameron", "given": "Isobel J." } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Kjaergaard-H-G", "name": { "family": "Kjaergaard", "given": "Henrik G." }, "orcid": "0000-0002-7275-8297" } ] }, "title": "Calculation of conformationally weighted dipole moments useful in ion-molecule collision rate estimates", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 2009 Elsevier. \n\nReceived 10 March 2009. In final form 14 April 2009. Available online 18 April 2009. \n\nWe would like to thank Joseph R. Lane and Mikkel Bo Hansen\nfor helpful discussions. We thank Daryl L. Howard for his EG calculations. We acknowledge the Marsden Fund administered by the Royal Society of New Zealand, the US National Science Foundation (ATM-0432377 and ATM-0340832), NASA (NNG06GB32B) and the University of Otago for financial support.", "abstract": "We have calculated relative energies and dipole moments of the stable conformers of nitrous acid, ethanol, ethylene glycol and propanone nitrate using a range of ab initio methods and basis sets. We have used these to calculate conformationally weighted dipole moments that are useful in estimates of collision rates between molecules and ions. We find that the average error in the conformationally weighted dipole moments is less than 5% for CCSD(T) with the aug-cc-pVTZ basis set, less than 10% for B3LYP/6-31G(d) and less than 20% for B3LYP/6-31+G(d) and B3LYP/aug-cc-pVTZ.", "date": "2009-05-25", "date_type": "published", "publication": "Chemical Physics Letters", "volume": "474", "number": "1-3", "publisher": "Elsevier", "pagerange": "45-50", "id_number": "CaltechAUTHORS:20090728-101042593", "issn": "0009-2614", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20090728-101042593", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Royal Society of New Zealand" }, { "agency": "NSF", "grant_number": "ATM-0432377" }, { "agency": "NSF", "grant_number": "ATM-0340832" }, { "agency": "NASA", "grant_number": "NNG06GB32B" }, { "agency": "University of Otago" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/j.cplett.2009.04.038", "resource_type": "article", "pub_year": "2009", "author_list": "Garden, Anna L.; Paulot, Fabien; et el." }, { "id": "https://authors.library.caltech.edu/records/y5jr4-rxn55", "eprint_id": 15029, "eprint_status": "archive", "datestamp": "2023-08-20 01:41:55", "lastmod": "2023-10-18 20:27:57", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Chan-Arthur-W-H", "name": { "family": "Chan", "given": "A. W. H." }, "orcid": "0000-0001-7392-4237" }, { "id": "Kautzman-K-E", "name": { "family": "Kautzman", "given": "K. E." } }, { "id": "Chhabra-Puneet-S", "name": { "family": "Chhabra", "given": "P. S." } }, { "id": "Surratt-Jason-D", "name": { "family": "Surratt", "given": "J. D." }, "orcid": "0000-0002-6833-1450" }, { "id": "Chan-Man-Nin", "name": { "family": "Chan", "given": "M. N." }, "orcid": "0000-0002-2384-2695" }, { "id": "Crounse-John-D", "name": { "family": "Crounse", "given": "J. D." }, "orcid": "0000-0001-5443-729X" }, { "id": "K\u00fcrten-Andreas", "name": { "family": "K\u00fcrten", "given": "A." }, "orcid": "0000-0002-8955-4450" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Flagan-R-C", "name": { "family": "Flagan", "given": "R. C." }, "orcid": "0000-0001-5690-770X" }, { "id": "Seinfeld-J-H", "name": { "family": "Seinfeld", "given": "J. H." }, "orcid": "0000-0003-1344-4068" } ] }, "title": "Secondary organic aerosol formation from photooxidation of naphthalene and alkylnaphthalenes: implications for oxidation of intermediate volatility organic compounds (IVOCs)", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 Author(s) 2009. This work is distributed under the Creative Commons Attribution 3.0 License. \n\nReceived: 27 November 2008 \u2013 Published in Atmos. Chem. Phys. Discuss.: 21 January 2009. Revised: 15 April 2009. Accepted: 23 April 2009. Published: 12 May 2009. \n\nThis research was funded by the Office of Science (BER), US Department of Energy Grant No. DE-FG02-05ER63983, US Environmental Protection Agency STAR Research Assistance Agreement No. RD-83374901 and US National Science Foundation grant ATM-0432377. This publication has not been\nformally reviewed by the EPA. The views expressed in this\ndocument are solely those of the authors and EPA does not endorse any products mentioned in this publication. The authors would like to thank D. R. Fitz for use of GC/NO2-PAN analyzer, L. D. Yee for assistance with running experiments, and C. E. Jordan for helpful discussion.\n\nPublished - Chan2009p4285Atmos_Chem_Phys.pdf
", "abstract": "Current atmospheric models do not include secondary organic aerosol (SOA) production from gas-phase reactions of polycyclic aromatic hydrocarbons (PAHs). Recent studies have shown that primary emissions undergo oxidation in the gas phase, leading to SOA formation. This opens the possibility that low-volatility gas-phase precursors are a potentially large source of SOA. In this work, SOA formation from gas-phase photooxidation of naphthalene, 1-methylnaphthalene (1-MN), 2-methylnaphthalene (2-MN), and 1,2-dimethylnaphthalene (1,2-DMN) is studied in the Caltech dual 28-m3 chambers. Under high-NOx conditions and aerosol mass loadings between 10 and 40 \u03bcg m\u22123, the SOA yields (mass of SOA per mass of hydrocarbon reacted) ranged from 0.19 to 0.30 for naphthalene, 0.19 to 0.39 for 1-MN, 0.26 to 0.45 for 2-MN, and constant at 0.31 for 1,2-DMN. Under low-NOx conditions, the SOA yields were measured to be 0.73, 0.68, and 0.58, for naphthalene, 1-MN, and 2-MN, respectively. The SOA was observed to be semivolatile under high-NOx conditions and essentially nonvolatile under low-NOx conditions, owing to the higher fraction of ring-retaining products formed under low-NOx conditions. When applying these measured yields to estimate SOA formation from primary emissions of diesel engines and wood burning, PAHs are estimated to yield 3\u20135 times more SOA than light aromatic compounds over photooxidation timescales of less than 12 h. PAHs can also account for up to 54% of the total SOA from oxidation of diesel emissions, representing a potentially large source of urban SOA.", "date": "2009-05-12", "date_type": "published", "publication": "Atmospheric Chemistry and Physics", "volume": "9", "number": "9", "publisher": "European Geosciences Union", "pagerange": "3049-3060", "id_number": "CaltechAUTHORS:20090814-103729079", "issn": "1680-7316", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20090814-103729079", "rights": "This work is distributed under the Creative Commons Attribution 3.0 License.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-FG02-05ER63983" }, { "agency": "Environmental Protection Agency (EPA)", "grant_number": "RD-83374901" }, { "agency": "NSF", "grant_number": "ATM-0432377" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/acp-9-3049-2009", "primary_object": { "basename": "Chan2009p4285Atmos_Chem_Phys.pdf", "url": "https://authors.library.caltech.edu/records/y5jr4-rxn55/files/Chan2009p4285Atmos_Chem_Phys.pdf" }, "resource_type": "article", "pub_year": "2009", "author_list": "Chan, A. W. H.; Kautzman, K. E.; et el." }, { "id": "https://authors.library.caltech.edu/records/fwhj1-0xy17", "eprint_id": 13955, "eprint_status": "archive", "datestamp": "2023-08-22 00:20:02", "lastmod": "2023-10-18 15:59:31", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Perring-A-E", "name": { "family": "Perring", "given": "A. E." } }, { "id": "Bertram-T-H", "name": { "family": "Bertram", "given": "T. H." }, "orcid": "0000-0002-3026-7588" }, { "id": "Wooldridge-P-J", "name": { "family": "Wooldridge", "given": "P. J." } }, { "id": "Fried-A", "name": { "family": "Fried", "given": "A." } }, { "id": "Heikes-B-G", "name": { "family": "Heikes", "given": "B. G." } }, { "id": "Dibb-J-E", "name": { "family": "Dibb", "given": "J." }, "orcid": "0000-0003-3096-7709" }, { "id": "Crounse-J-D", "name": { "family": "Crounse", "given": "J. D." }, "orcid": "0000-0001-5443-729X" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Blake-N-J", "name": { "family": "Blake", "given": "N. J." } }, { "id": "Blake-D-R", "name": { "family": "Blake", "given": "D. R." } }, { "id": "Brune-W-H", "name": { "family": "Brune", "given": "W. H." }, "orcid": "0000-0002-1609-4051" }, { "id": "Singh-H-B", "name": { "family": "Singh", "given": "H. B." } }, { "id": "Cohen-R-C", "name": { "family": "Cohen", "given": "R. C." }, "orcid": "0000-0001-6617-7691" } ] }, "title": "Airborne observations of total RONO2: new constraints on the yield and lifetime of isoprene nitrates", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 Author(s) 2009. This work is distributed under\nthe Creative Commons Attribution 3.0 License. \n\nReceived: 16 May 2008 \u2013 Published in Atmos. Chem. Phys. Discuss.: 24 June 2008. Revised: 26 January 2009 \u2013 Accepted: 26 January 2009 \u2013 Published: 23 February 2009. \n\nThe analysis described here was funded by\nNASA grants NNG05GH196 and NAG5-13668 and by NASA\nheadquarters under the NASA Earth and Space Science Fellowship\nProgram. The authors would also like to sincerely thank the NASA\nDC8 flight and ground crews for invaluable logistical support,\nthe DC8 science team for an incredibly creative and rewarding\ncollaboration and especially Melody Avery for editorial input.\n\nPublished - Perring2009p650.pdf
", "abstract": "Formation of isoprene nitrates (INs) is an important free radical chain termination step ending production of ozone and possibly affecting formation of secondary organic aerosol. Isoprene nitrates also represent a potentially large, unmeasured contribution to OH reactivity and are a major pathway for the removal of nitrogen oxides from the atmosphere. Current assessments indicate that formation rates of isoprene nitrates are uncertain to a factor of 2\u20133 and the subsequent fate of isoprene nitrates remains largely unconstrained by laboratory, field or modeling studies. Measurements of total alkyl and multifunctional nitrates (\u03a3ANs), NO2, total peroxy nitrates (\u03a3PNs), HNO3, CH2O, isoprene and other VOC were obtained from the NASA DC-8 aircraft during summer 2004 over the continental US during the INTEX-NA campaign. These observations represent the first characterization of \u03a3ANs over a wide range of land surface types and in the lower free troposphere. \u03a3ANs were a significant, 12\u201320%, fraction of NOy throughout the experimental domain and \u03a3ANs were more abundant when isoprene was high. We use the observed hydrocarbon species to calculate the relative contributions of \u03a3AN precursors to their production. These calculations indicate that isoprene represents at least three quarters of the \u03a3AN source in the summertime continental boundary layer of the US. An observed correlation between \u03a3ANs and CH2O is used to place constraints on nitrate yields from isoprene oxidation, atmospheric lifetimes of the resulting nitrates and recycling efficiencies of nitrates during subsequent oxidation. We find reasonable fits to the data using sets of production rates, lifetimes and recycling efficiencies of INs as follows (4.4%, 16 h, 97%), (8%, 2.5 h, 79%) and (12%, 95 min, 67%). The analysis indicates that the lifetime of \u03a3ANs as a pool of compounds is considerably longer than the lifetime of the individual isoprene nitrates to reaction with OH, implying that the organic nitrate functionality is at least partially maintained through a second oxidation cycle.", "date": "2009-02-23", "date_type": "published", "publication": "Atmospheric Chemistry and Physics", "volume": "9", "number": "4", "publisher": "European Geosciences Union", "pagerange": "1451-1463", "id_number": "CaltechAUTHORS:20090413-132844349", "issn": "1680-7316", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20090413-132844349", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NNG05GH196" }, { "agency": "NASA", "grant_number": "NAG5-13668" }, { "agency": "NASA Earth and Space Science Fellowship" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/acp-9-1451-2009", "primary_object": { "basename": "Perring2009p650.pdf", "url": "https://authors.library.caltech.edu/records/fwhj1-0xy17/files/Perring2009p650.pdf" }, "resource_type": "article", "pub_year": "2009", "author_list": "Perring, A. E.; Bertram, T. H.; et el." }, { "id": "https://authors.library.caltech.edu/records/9xw4j-wcz86", "eprint_id": 13957, "eprint_status": "archive", "datestamp": "2023-08-22 00:20:10", "lastmod": "2023-10-18 15:59:40", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Paulot-F", "name": { "family": "Paulot", "given": "F." }, "orcid": "0000-0001-7534-4922" }, { "id": "Crounse-J-D", "name": { "family": "Crounse", "given": "J. D." }, "orcid": "0000-0001-5443-729X" }, { "id": "Kjaergaard-H-G", "name": { "family": "Kjaergaard", "given": "H. G." }, "orcid": "0000-0002-7275-8297" }, { "id": "Kroll-J-H", "name": { "family": "Kroll", "given": "J. H." } }, { "id": "Seinfeld-J-H", "name": { "family": "Seinfeld", "given": "J. H." }, "orcid": "0000-0003-1344-4068" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "Isoprene photooxidation : new insights into the production of acids and organic nitrates", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 Author(s) 2009. This work is distributed under the Creative Commons Attribution 3.0 License. \n\nReceived: 10 June 2008 \u2013 Published in Atmos. Chem. Phys. Discuss.: 31 July 2008. Revised: 4 February 2009 \u2013 Accepted: 4 February 2009 \u2013 Published: 23 February 2009. \n\nThe authors wish to thank T. S. Dibble,\nD. Taraborrelli and an anonymous referee for their helpful\ncomments on the initial manuscript. F. Paulot wishes to thank\nC. D. Vecitis for helpful discussions regarding chemical mechanisms.\nThis study was supported by the National Science\nFoundation (NSF) under grant ATM-0432377, by the US Department\nof Energy under grant DE-FG02-05ER63983, by US\nEnvironmental Protection Agency under grant RD-83374901\nand by the Marsden Fund administrated by the Royal Society of\nNew Zealand. F. Paulot is supported by the William and Sonya\nDavidow graduate fellowship. J. D. Crounse thanks the EPA-STAR\nFellowship Program (FP916334012) for providing support. This\nwork has not been formally reviewed by the EPA. The views\nexpressed in this document are solely those of the authors and\nthe EPA does not endorse any products or commercial services\nmentioned in this publication.\n\nPublished - Paulot2009p656.pdf
", "abstract": "We describe a nearly explicit chemical mechanism for isoprene photooxidation guided by chamber studies that include time-resolved observation of an extensive suite of volatile compounds. We provide new constraints on the chemistry of the poorly-understood isoprene \u03b4-hydroxy channels, which account for more than one third of the total isoprene carbon flux and a larger fraction of the nitrate yields. We show that the cis branch dominates the chemistry of the \u03b4-hydroxy channel with less than 5% of the carbon following the trans branch. The modelled yield of isoprene nitrates is 12\u00b13% with a large difference between the \u03b4 and \u03b2 branches. The oxidation of these nitrates releases about 50% of the NOx. Methacrolein nitrates (modelled yield \u224315\u00b13% from methacrolein) and methylvinylketone nitrates (modelled yield \u224311\u00b13% yield from methylvinylketone) are also observed. Propanone nitrate, produced with a yield of 1% from isoprene, appears to be the longest-lived nitrate formed in the total oxidation of isoprene. We find a large molar yield of formic acid and suggest a novel mechanism leading to its formation from the organic nitrates. Finally, the most important features of this mechanism are summarized in a condensed scheme appropriate for use in global chemical transport models.", "date": "2009-02-23", "date_type": "published", "publication": "Atmospheric Chemistry and Physics", "volume": "9", "number": "4", "publisher": "European Geosciences Union", "pagerange": "1479-1501", "id_number": "CaltechAUTHORS:20090413-143557131", "issn": "1680-7316", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20090413-143557131", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "ATM-0432377" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-FG02-05ER63983" }, { "agency": "Environmental Protection Agency (EPA)", "grant_number": "RD-83374901" }, { "agency": "Marsden Fund administrated by the Royal Society of New Zealand" }, { "agency": "William and Sonya Davidow graduate fellowship" }, { "agency": "Environmental Protection Agency (EPA)", "grant_number": "FP916334012" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/acp-9-1479-2009", "primary_object": { "basename": "Paulot2009p656.pdf", "url": "https://authors.library.caltech.edu/records/9xw4j-wcz86/files/Paulot2009p656.pdf" }, "resource_type": "article", "pub_year": "2009", "author_list": "Paulot, F.; Crounse, J. D.; et el." }, { "id": "https://authors.library.caltech.edu/records/bxshk-03x25", "eprint_id": 12034, "eprint_status": "archive", "datestamp": "2023-08-22 12:40:21", "lastmod": "2023-10-17 16:29:08", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Ng-Nga-Lee", "name": { "family": "Ng", "given": "N. L." }, "orcid": "0000-0001-8460-4765" }, { "id": "Kwan-Alan-J", "name": { "family": "Kwan", "given": "A. J." } }, { "id": "Surratt-Jason-D", "name": { "family": "Surratt", "given": "J. D." }, "orcid": "0000-0002-6833-1450" }, { "id": "Chan-Arthur-W-H", "name": { "family": "Chan", "given": "A. W. H." }, "orcid": "0000-0001-7392-4237" }, { "id": "Chhabra-Puneet-S", "name": { "family": "Chhabra", "given": "P. S." } }, { "id": "Sorooshian-Armin", "name": { "family": "Sorooshian", "given": "A." }, "orcid": "0000-0002-2243-2264" }, { "id": "Pye-Havala-O-T", "name": { "family": "Pye", "given": "Havala O. T." }, "orcid": "0000-0002-2014-2140" }, { "id": "Crounse-John-D", "name": { "family": "Crounse", "given": "J. D." }, "orcid": "0000-0001-5443-729X" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Flagan-R-C", "name": { "family": "Flagan", "given": "R. C." }, "orcid": "0000-0001-5690-770X" }, { "id": "Seinfeld-J-H", "name": { "family": "Seinfeld", "given": "J. H." }, "orcid": "0000-0003-1344-4068" } ] }, "title": "Secondary organic aerosol (SOA) formation from reaction of isoprene with nitrate radicals (NO\u2083)", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 Author(s) 2008. This work is distributed under the Creative Commons Attribution 3.0 License. \n\nReceived: 3 January 2008 \u2013 Published in Atmos. Chem. Phys. Discuss.: 15 February 2008. Revised: 3 July 2008 \u2013 Accepted: 3 July 2008 \u2013 Published: 1 August 2008. \n\nThis research was funded by US Department of Energy Biological and Environmental Research Program DE-FG02-05ER63983. This material is based in part on work supported by the National Science Foundation (NSF) under grant ATM-0432377. The Waters LCT Premier XT time-of-flight mass spectrometer interfaced to a Waters UPLC system was purchased in 2006 with a grant from the National Science Foundation, Chemistry Research Instrumentation and Facilities Program (CHE-0541745). The LCQ Ion Trap mass spectrometer was purchased in 1997 with funds from the National Science Foundation through the CRIF program (CHE-9709233). J.D. Surratt is supported in part by the US EPA under the STAR Graduate Fellowship Program. A.J. Kwan and H.O.T. Pye acknowledge the support of NSF graduate research fellowships. The authors would like to thank C.D. Vecitis, J. Cheng, and M.R. Hoffmann for use of and aid with their ozonizer and UV-VIS spectrometer; to K. Takematsu and M. Okumura for helpful advice on preparing N\u2082O\u2085; to J.H. Kroll and M. Claeys for helpful discussions and suggestions; to M.N. Chan for assistance with filter sample collection; to H.G. Kjaergaard and F. Paulot for performing the quantum calculations and estimating the sensitivities of CIMS to various gas-phase products; and to Y. Yu and the reviewers for helpful comments on the manuscript.\n\nPublished - NGNacp08.pdf
", "abstract": "Secondary organic aerosol (SOA) formation from the reaction of isoprene with nitrate radicals (NO\u2083) is investigated in the Caltech indoor chambers. Experiments are performed in the dark and under dry conditions (RH < 10%) using N\u2082O\u2085 as a source of NO\u2083 radicals. For an initial isoprene concentration of 18.4 to 101.6 ppb, the SOA yield (defined as the ratio of the mass of organic aerosol formed to the mass of parent hydrocarbon reacted) ranges from 4.3% to 23.8%. By examining the time evolutions of gas-phase intermediate products and aerosol volume in real time, we are able to constrain the chemistry that leads to the formation of low-volatility products. Although the formation of ROOR from the reaction of two peroxy radicals (RO\u2082) has generally been considered as a minor channel, based on the gas-phase and aerosol-phase data it appears that RO\u2082+RO\u2082 reaction (self reaction or cross-reaction) in the gas phase yielding ROOR products is a dominant SOA formation pathway. A wide array of organic nitrates and peroxides are identified in the aerosol formed and mechanisms for SOA formation are proposed. Using a uniform SOA yield of 10% (corresponding to M\u2092 \u2245 10 \u03bcg m\u207b\u00b3), it is estimated that ~2 to 3 Tg yr\u207b\u00b9 of SOA results from isoprene + NO\u2083. The extent to which the results from this study can be applied to conditions in the atmosphere depends on the fate of peroxy radicals in the nighttime troposphere.", "date": "2008-08-01", "date_type": "published", "publication": "Atmospheric Chemistry and Physics", "volume": "8", "number": "14", "publisher": "European Geosciences Union", "pagerange": "4117-4140", "id_number": "CaltechAUTHORS:NGNacp08", "issn": "1680-7316", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:NGNacp08", "rights": "The article and any associated published material is distributed under the Creative Commons Attribution 3.0 License.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-FG02-05ER63983" }, { "agency": "NSF", "grant_number": "ATM-0432377" }, { "agency": "NSF", "grant_number": "CHE-0541745" }, { "agency": "NSF", "grant_number": "CHE-9709233" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/acp-8-4117-2008", "primary_object": { "basename": "NGNacp08.pdf", "url": "https://authors.library.caltech.edu/records/bxshk-03x25/files/NGNacp08.pdf" }, "resource_type": "article", "pub_year": "2008", "author_list": "Ng, N. L.; Kwan, A. J.; et el." }, { "id": "https://authors.library.caltech.edu/records/7khr9-2s245", "eprint_id": 14149, "eprint_status": "archive", "datestamp": "2023-08-22 12:33:13", "lastmod": "2023-10-18 16:10:04", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "DeCarlo-P-F", "name": { "family": "DeCarlo", "given": "P. F." } }, { "id": "Dunlea-E-J", "name": { "family": "Dunlea", "given": "E. J." } }, { "id": "Kimmel-J-R", "name": { "family": "Kimmel", "given": "J. R." } }, { "id": "Aiken-A-C", "name": { "family": "Aiken", "given": "A. C." } }, { "id": "Sueper-D", "name": { "family": "Sueper", "given": "D." } }, { "id": "Crounse-J-D", "name": { "family": "Crounse", "given": "J." }, "orcid": "0000-0001-5443-729X" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Emmons-L", "name": { "family": "Emmons", "given": "L." } }, { "id": "Shinozuka-Yohei", "name": { "family": "Shinozuka", "given": "Y." } }, { "id": "Clarke-A", "name": { "family": "Clarke", "given": "A." } }, { "id": "Zhou-J", "name": { "family": "Zhou", "given": "J." } }, { "id": "Tomlinson-J", "name": { "family": "Tomlinson", "given": "J." } }, { "id": "Collins-D-R", "name": { "family": "Collins", "given": "D. R." } }, { "id": "Knapp-D", "name": { "family": "Knapp", "given": "D." } }, { "id": "Weinheimer-A-J", "name": { "family": "Weinheimer", "given": "A. J." }, "orcid": "0000-0001-6175-8286" }, { "id": "Montzka-D-D", "name": { "family": "Montzka", "given": "D. D." } }, { "id": "Campos-T", "name": { "family": "Campos", "given": "T." } }, { "id": "Jimenez-J-L", "name": { "family": "Jimenez", "given": "J. L." }, "orcid": "0000-0001-6203-1847" } ] }, "title": "Fast airborne aerosol size and chemistry measurements above Mexico City and Central Mexico during the MILAGRO campaign", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 Author(s) 2008. 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: 22 November 2007 \u2013 Published in Atmos. Chem. Phys. Discuss.: 20 December 2007. Revised: 20 June 2008 \u2013 Accepted: 20 June 2008 \u2013 Published: 25 July 2008. \n\nWe are grateful to the NCAR RAF and C-130 personnel for much help and guidance during integration and research flights, especially A. Schanot, P. Romashkin, and M. Lord. We thank R. Bahreini, C. Simmons, and A. Middlebrook of NOAA for help with integration and the PCI. We thank C. Brock of NOAA for providing Mie Scattering code in the Igor programming language. We are also grateful to the rest of the C-130 investigators and the Jimenez group for many helpful discussions. This study was supported by grants NSF ATM-0513116, ATM-0528634, and ATM-0449815, NASA NNG04GA67G and NNG06GB03G, UCAR/NSF S05-39607, and by EPA fellowship FP-91650801 (to PFD) and NASA fellowship NNG04GR06H (to ACA).\n\nPublished - DECacp08.pdf
Supplemental Material - DECacp08supp.pdf
", "abstract": "The concentration, size, and composition of non-refractory submicron aerosol (NR-PM1) was measured over Mexico City and central Mexico with a High-Resolution Time-of-Flight Aerosol Mass Spectrometer (HR-ToF-AMS) onboard the NSF/NCAR C-130 aircraft as part of the MILAGRO field campaign. This was the first aircraft deployment of the HR-ToF-AMS. During the campaign the instrument performed very well, and provided 12 s data. The aerosol mass from the AMS correlates strongly with other aerosol measurements on board the aircraft. Organic aerosol (OA) species dominate the NR-PM1 mass. OA correlates strongly with CO and HCN indicating that pollution (mostly secondary OA, SOA) and biomass burning (BB) are the main OA sources. The OA to CO ratio indicates a typical value for aged air of around 80 \u03bcg m\u22123 (STP) ppm\u22121. This is within the range observed in outflow from the Northeastern US, which could be due to a compensating effect between higher BB but lower biogenic VOC emissions during this study. The O/C atomic ratio for OA is calculated from the HR mass spectra and shows a clear increase with photochemical age, as SOA forms rapidly and quickly overwhelms primary urban OA, consistent with Volkamer et al. (2006) and Kleinman et al. (2008). The stability of the OA/CO while O/C increases with photochemical age implies a net loss of carbon from the OA. BB OA is marked by signals at m/z 60 and 73, and also by a signal enhancement at large m/z indicative of larger molecules or more resistance to fragmentation. The main inorganic components show different spatial patterns and size distributions. Sulfate is regional in nature with clear volcanic and petrochemical/power plant sources, while the urban area is not a major regional source for this species. Nitrate is enhanced significantly in the urban area and immediate outflow, and is strongly correlated with CO indicating a strong urban source. The importance of nitrate decreases with distance from the city likely due to evaporation. BB does not appear to be a strong source of nitrate despite its high emissions of nitrogen oxides, presumably due to low ammonia emissions. NR-chloride often correlates with HCN indicating a fire source, although other sources likely contribute as well. This is the first aircraft study of the regional evolution of aerosol chemistry from a tropical megacity.", "date": "2008-07-25", "date_type": "published", "publication": "Atmospheric Chemistry and Physics", "volume": "8", "number": "14", "publisher": "European Geosciences Union", "pagerange": "4027-4048", "id_number": "CaltechAUTHORS:20090504-131712264", "issn": "1680-7316", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20090504-131712264", "rights": "This work is distributed under the Creative Commons Attribution 3.0 License.", "funders": { "items": [ { "agency": "NSF", "grant_number": "ATM-0513116" }, { "agency": "NSF", "grant_number": "ATM-0528634" }, { "agency": "NSF", "grant_number": "ATM-0449815" }, { "agency": "NASA", "grant_number": "NNG04GA67G" }, { "agency": "NASA", "grant_number": "NNG06GB03G" }, { "agency": "NSF", "grant_number": "S05-39607" }, { "agency": "Environmental Protection Agency (EPA)", "grant_number": "FP-91650801" }, { "agency": "NASA", "grant_number": "NNG04GR06H" }, { "agency": "University Corporation for Atmospheric Research" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/acp-8-4027-2008", "primary_object": { "basename": "DECacp08.pdf", "url": "https://authors.library.caltech.edu/records/7khr9-2s245/files/DECacp08.pdf" }, "related_objects": [ { "basename": "DECacp08supp.pdf", "url": "https://authors.library.caltech.edu/records/7khr9-2s245/files/DECacp08supp.pdf" } ], "resource_type": "article", "pub_year": "2008", "author_list": "DeCarlo, P. F.; Dunlea, E. J.; et el." }, { "id": "https://authors.library.caltech.edu/records/h71c5-xet17", "eprint_id": 10557, "eprint_status": "archive", "datestamp": "2023-08-22 11:46:05", "lastmod": "2023-10-16 22:56:10", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Matthews-J", "name": { "family": "Matthews", "given": "Jamie" } }, { "id": "Fry-J-L", "name": { "family": "Fry", "given": "Julie L." } }, { "id": "Roehl-C-M", "name": { "family": "Roehl", "given": "Coleen M." }, "orcid": "0000-0001-5383-8462" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Sinha-A", "name": { "family": "Sinha", "given": "Amitabha" }, "orcid": "0000-0002-7122-3549" } ] }, "title": "Vibrational overtone initiated unimolecular dissociation of HOCH_2OOH and HOCD_2OOH: Evidence for mode selective behavior", "ispublished": "pub", "full_text_status": "public", "keywords": "bonds (chemical), dissociation, organic compounds, spectrochemical analysis, vibrational modes", "note": "\u00a9 2008 American Institute of Physics. \n\nReceived 1 February 2008; accepted 27 March 2008; published 9 May 2008. \n\nFunding for this work was provided by grants to A.S. from the National Science Foundation Division of Chemistry (CHE-0642640) and to P.O.W. from the National Science Foundation Division of Atmospheric Sciences (ATM-0432377). We also thank Dr. Shuping Li for assistance with certain portions of the measurements.\n\nPublished - MATjcp08.pdf
", "abstract": "The vibrational overtone induced unimolecular dissociation of HMHP (HOCH2OOH) and HMHP-d2 (HOCD2OOH) into OH and HOCH2O (HOCD2O) fragments is investigated in the region of the 4nuOH and 5nuOH bands. The unimolecular dissociation rates in the threshold region, corresponding to the 4nuOH band, exhibit measurable differences associated with excitation of the OH stretch of the alcohol versus the peroxide functional group, with the higher energy alcohol OH stretching state exhibiting a slower dissociation rate compared to the lower energy peroxide OH stretch in both HMHP and HMHP-d2. Predictions using the Rice\u2013Ramsperger\u2013Kassel\u2013Marcus theory give rates that are in reasonably good agreement with the measured dissociation rate for the alcohol OH stretch but considerably differ from the measured rates for the peroxide OH stretch in both isotopomers. The present results are interpreted as suggesting that the extent of intramolecular vibrational energy redistribution (IVR) is different for the two OH stretching states associated with the two functional groups in HMHP, with IVR being substantially less complete for the peroxide OH stretch. Analysis of the OH fragment product state distributions in conjunction with phase-space theory simulation gives a D0 value of 38\u00b10.7 kcal/mole for breaking the peroxide bond in HMHP.", "date": "2008-05-14", "date_type": "published", "publication": "Journal of Chemical Physics", "volume": "128", "number": "18", "publisher": "American Institute of Physics", "pagerange": "Art. No. 184306", "id_number": "CaltechAUTHORS:MATjcp08", "issn": "0021-9606", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:MATjcp08", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "CHE-0642640" }, { "agency": "NSF", "grant_number": "ATM-0432377" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1063/1.2912063", "primary_object": { "basename": "MATjcp08.pdf", "url": "https://authors.library.caltech.edu/records/h71c5-xet17/files/MATjcp08.pdf" }, "resource_type": "article", "pub_year": "2008", "author_list": "Matthews, Jamie; Fry, Julie L.; et el." }, { "id": "https://authors.library.caltech.edu/records/s14pd-ks526", "eprint_id": 12273, "eprint_status": "archive", "datestamp": "2023-08-22 11:31:55", "lastmod": "2023-10-17 16:39:21", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Heald-C-L", "name": { "family": "Heald", "given": "C. L." } }, { "id": "Goldstein-A-H", "name": { "family": "Goldstein", "given": "A. H." }, "orcid": "0000-0003-4014-4896" }, { "id": "Allan-J-D", "name": { "family": "Allan", "given": "J. D." } }, { "id": "Aiken-A-C", "name": { "family": "Aiken", "given": "A. C." } }, { "id": "Apel-E", "name": { "family": "Apel", "given": "E." } }, { "id": "Atlas-E-L", "name": { "family": "Atlas", "given": "E. L." }, "orcid": "0000-0003-3847-5346" }, { "id": "Baker-A-K", "name": { "family": "Baker", "given": "A. K." } }, { "id": "Bates-T-S", "name": { "family": "Bates", "given": "T. S." } }, { "id": "Beyersdorf-A-J", "name": { "family": "Beyersdorf", "given": "A. J." }, "orcid": "0000-0002-4496-2557" }, { "id": "Blake-D-R", "name": { "family": "Blake", "given": "D. R." } }, { "id": "Campos-T", "name": { "family": "Campos", "given": "T." } }, { "id": "Coe-H", "name": { "family": "Coe", "given": "H." } }, { "id": "Crounse-J-D", "name": { "family": "Crounse", "given": "J. D." }, "orcid": "0000-0001-5443-729X" }, { "id": "DeCarlo-P-F", "name": { "family": "DeCarlo", "given": "P. F." } }, { "id": "de-Gouw-J-A", "name": { "family": "de Gouw", "given": "J. A." }, "orcid": "0000-0002-0385-1826" }, { "id": "Dunlea-E-J", "name": { "family": "Dunlea", "given": "E. J." } }, { "id": "Flocke-F-M", "name": { "family": "Flocke", "given": "F. M." } }, { "id": "Fried-A", "name": { "family": "Fried", "given": "A." } }, { "id": "Goldan-P", "name": { "family": "Goldan", "given": "P." } }, { "id": "Griffin-R-J", "name": { "family": "Griffin", "given": "R. J." } }, { "id": "Herndon-S-C", "name": { "family": "Herndon", "given": "S. C." } }, { "id": "Holloway-J-S", "name": { "family": "Holloway", "given": "J. S." } }, { "id": "Holzinger-R", "name": { "family": "Holzinger", "given": "R." } }, { "id": "Jimenez-J-L", "name": { "family": "Jimenez", "given": "J. L." }, "orcid": "0000-0001-6203-1847" }, { "id": "Junkermann-W", "name": { "family": "Junkermann", "given": "W." } }, { "id": "Kuster-W-C", "name": { "family": "Kuster", "given": "W. C." } }, { "id": "Lewis-A-C", "name": { "family": "Lewis", "given": "A. C." } }, { "id": "Meinardi-S", "name": { "family": "Meinardi", "given": "S." } }, { "id": "Millet-D-B", "name": { "family": "Millet", "given": "D. B." } }, { "id": "Onasch-T-B", "name": { "family": "Onasch", "given": "T." } }, { "id": "Polidori-A", "name": { "family": "Polidori", "given": "A." } }, { "id": "Quinn-P-K", "name": { "family": "Quinn", "given": "P. K." } }, { "id": "Riemer-D-D", "name": { "family": "Riemer", "given": "D. D." } }, { "id": "Roberts-J-M", "name": { "family": "Roberts", "given": "J. M." } }, { "id": "Salcedo-D", "name": { "family": "Salcedo", "given": "D." } }, { "id": "Sive-B", "name": { "family": "Sive", "given": "B." } }, { "id": "Swanson-A-L", "name": { "family": "Swanson", "given": "A. L." } }, { "id": "Talbot-R-W", "name": { "family": "Talbot", "given": "R." } }, { "id": "Warneke-C", "name": { "family": "Warneke", "given": "C." } }, { "id": "Weber-R-J", "name": { "family": "Weber", "given": "R. J." } }, { "id": "Weibring-P", "name": { "family": "Weibring", "given": "P." } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Worsnop-D-R", "name": { "family": "Worsnop", "given": "D. R." }, "orcid": "0000-0002-8928-8017" }, { "id": "Wittig-A-E", "name": { "family": "Wittig", "given": "A. E." } }, { "id": "Zhang-R", "name": { "family": "Zhang", "given": "R." } }, { "id": "Zheng-J", "name": { "family": "Zheng", "given": "J." } }, { "id": "Zheng-W", "name": { "family": "Zheng", "given": "W." } } ] }, "title": "Total observed organic carbon (TOOC) in the atmosphere: a synthesis of North American observations", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 Author(s) 2008. This work is distributed under the Creative Commons Attribution 3.0 License. \n\nReceived: 26 October 2007 \u2013 Published in Atmos. Chem. Phys. Discuss.: 13 December 2007. Revised: 7 March 2008 \u2013 Accepted: 25 March 2008 \u2013 Published: 8 April 2008. \n\nThis work was supported by the NOAA Postdoctoral Program in Climate and Global Change, administered by the University Corporation for Atmospheric Research. Field measurements were supported by NOAA (under grants RA133R05SE4459, RA133R04SE0368, NA17RP2632, NA03OAR4600122, NA04OAR4600154 and NA05OAR4600189) NSF (under grants ATM-0449815 and ATM-0513116) and NASA (under grant NNG06GB03G). We thank B. Lerner for providing the CO observations aboard the R/V R. Brown, M. Evans for providing the BAe-146 merged data, R. Cohen, D. Farmer, and J. Fry for useful discussions and gratefully acknowledge core data from the BAe 146 aircraft provided by the UK Facility for Airborne Atmospheric Measurements. \n\nEdited by: A. Hofzumahaus\n\nPublished - HEAacp08.pdf
", "abstract": "Measurements of organic carbon compounds in both the gas and particle phases made upwind, over and downwind of North America are synthesized to examine the total observed organic carbon (TOOC) in the atmosphere over this region. These include measurements made aboard the NOAA WP-3 and BAe-146 aircraft, the NOAA research vessel Ronald H. Brown, and at the Thompson Farm and Chebogue Point surface sites during the summer 2004 ICARTT campaign. Both winter and summer 2002 measurements during the Pittsburgh Air Quality Study are also included. Lastly, the spring 2002 observations at Trinidad Head, CA, surface measurements made in March 2006 in Mexico City and coincidentally aboard the C-130 aircraft during the MILAGRO campaign and later during the IMPEX campaign off the northwestern United States are incorporated. Concentrations of TOOC in these datasets span more than two orders of magnitude. The daytime mean TOOC ranges from 4.0 to 456 \u03bcgC m^\u22123 from the cleanest site (Trinidad Head) to the most polluted (Mexico City). Organic aerosol makes up 3\u201317% of this mean TOOC, with highest fractions reported over the northeastern United States, where organic aerosol can comprise up to 50% of TOOC. Carbon monoxide concentrations explain 46 to 86% of the variability in TOOC, with highest TOOC/CO slopes in regions with fresh anthropogenic influence, where we also expect the highest degree of mass closure for TOOC. Correlation with isoprene, formaldehyde, methyl vinyl ketone and methacrolein also indicates that biogenic activity contributes substantially to the variability of TOOC, yet these tracers of biogenic oxidation sources do not explain the variability in organic aerosol observed over North America. We highlight the critical need to develop measurement techniques to routinely detect total gas phase VOCs, and to deploy comprehensive suites of TOOC instruments in diverse environments to quantify the ambient evolution of organic carbon from source to sink.", "date": "2008-04-08", "date_type": "published", "publication": "Atmospheric Chemistry and Physics", "volume": "8", "number": "7", "publisher": "European Geosciences Union", "pagerange": "2007-2025", "id_number": "CaltechAUTHORS:HEAacp08", "issn": "1680-7316", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:HEAacp08", "rights": "This work is distributed under the Creative Commons Attribution 3.0 License.", "funders": { "items": [ { "agency": "National Oceanic and Atmospheric Administration (NOAA)", "grant_number": "RA133R05SE4459" }, { "agency": "National Oceanic and Atmospheric Administration (NOAA)", "grant_number": "RA133R04SE0368" }, { "agency": "National Oceanic and Atmospheric Administration (NOAA)", "grant_number": "NA17RP2632" }, { "agency": "National Oceanic and Atmospheric Administration (NOAA)", "grant_number": "NA03OAR4600122" }, { "agency": "National Oceanic and Atmospheric Administration (NOAA)", "grant_number": "NA04OAR4600154" }, { "agency": "National Oceanic and Atmospheric Administration (NOAA)", "grant_number": "NA05OAR4600189" }, { "agency": "NSF", "grant_number": "ATM-0449815" }, { "agency": "NSF", "grant_number": "ATM-0513116" }, { "agency": "NASA", "grant_number": "NNG06GB03G" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/acp-8-2007-2008", "primary_object": { "basename": "HEAacp08.pdf", "url": "https://authors.library.caltech.edu/records/s14pd-ks526/files/HEAacp08.pdf" }, "resource_type": "article", "pub_year": "2008", "author_list": "Heald, C. L.; Goldstein, A. H.; et el." }, { "id": "https://authors.library.caltech.edu/records/e4kdt-emb40", "eprint_id": 46648, "eprint_status": "archive", "datestamp": "2023-08-22 11:23:32", "lastmod": "2023-10-26 19:54:25", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Dabdub-D", "name": { "family": "Dabdub", "given": "Donald" } } ] }, "title": "Atmospheric chemistry - Rethinking ozone production", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 2008 American Association for the Advancement of Science.", "abstract": "More than a hundred million people\nlive in cities that fail to meet international\nstandards for air quality.\nEfforts to improve conditions in these urban\nareas have usually focused on reducing\nemissions of reactive hydrocarbons (such\nas unburned gasoline vapors), nitrogen oxide\nfree radicals (NO and NO_2, together known as\nNO_x), and primary and secondary sources of\nparticulate matter (such as diesel smoke\nand sulfur dioxide). Control strategies have\nchanged over time in response to evolving\nunderstanding about atmospheric photochemistry\nand the impact of urban emissions on air\nquality downwind of cities (1, 2). The results\nreported by Li et al. on page 1657 of this issue\n(3) may require another rethinking of these\ncontrol strategies.", "date": "2008-03-21", "date_type": "published", "publication": "Science", "volume": "319", "number": "5870", "publisher": "American Association for the Advancement of Science", "pagerange": "1624-1625", "id_number": "CaltechAUTHORS:20140702-154023682", "issn": "0036-8075", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140702-154023682", "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.1155747", "resource_type": "article", "pub_year": "2008", "author_list": "Wennberg, Paul O. and Dabdub, Donald" }, { "id": "https://authors.library.caltech.edu/records/dhbgx-6st36", "eprint_id": 46633, "eprint_status": "archive", "datestamp": "2023-08-22 11:21:47", "lastmod": "2023-10-26 19:53:35", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Ren-Xinrong", "name": { "family": "Ren", "given": "Xinrong" } }, { "id": "Olson-J-R", "name": { "family": "Olson", "given": "Jennifer R." } }, { "id": "Crawford-J-H", "name": { "family": "Crawford", "given": "James H." } }, { "id": "Brune-W-H", "name": { "family": "Brune", "given": "William H." }, "orcid": "0000-0002-1609-4051" }, { "id": "Mao-Jingqiu", "name": { "family": "Mao", "given": "Jingqiu" } }, { "id": "Long-R-B", "name": { "family": "Long", "given": "Robert B." } }, { "id": "Chen-Zhong", "name": { "family": "Chen", "given": "Zhong" } }, { "id": "Chen-Gao", "name": { "family": "Chen", "given": "Gao" } }, { "id": "Avery-M-A", "name": { "family": "Avery", "given": "Melody A." } }, { "id": "Sachse-G-W", "name": { "family": "Sachse", "given": "Glen W." } }, { "id": "Barrick-J-D", "name": { "family": "Barrick", "given": "John D." } }, { "id": "Diskin-G-S", "name": { "family": "Diskin", "given": "Glenn S." }, "orcid": "0000-0002-3617-0269" }, { "id": "Huey-L-G", "name": { "family": "Huey", "given": "L. Greg" }, "orcid": "0000-0002-0518-7690" }, { "id": "Fried-A", "name": { "family": "Fried", "given": "Alan" } }, { "id": "Cohen-R-C", "name": { "family": "Cohen", "given": "Ronald C." }, "orcid": "0000-0001-6617-7691" }, { "id": "Heikes-B", "name": { "family": "Heikes", "given": "Brian" } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Singh-H-B", "name": { "family": "Singh", "given": "Hanwant B." } }, { "id": "Blake-D-R", "name": { "family": "Blake", "given": "Donald R." } }, { "id": "Shetter-R-E", "name": { "family": "Shetter", "given": "Richard E." } } ] }, "title": "HO_x chemistry during INTEX-A 2004: Observation, model calculation, and comparison with previous studies", "ispublished": "pub", "full_text_status": "public", "keywords": "hydroxyl radical; hydroperoxyl radical", "note": "\u00a9 2008 American Geophysical Union. \n\nReceived 13 July 2007; revised 24 October 2007; accepted 18 December 2007; article first published online 8 March 2008. \n\nThe work was supported by the NASA Tropospheric Chemistry Program. The authors would like to thank the DC-8 crew and support staff during the INTEX-A preparation and deployment periods for making this work possible.\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 - jgrd14262.pdf
Supplemental Material - jgrd14262-sup-0001-t01.txt
", "abstract": "OH and HO_2 were measured with the Airborne Tropospheric Hydrogen Oxides Sensor (ATHOS) as part of a large measurement suite from the NASA DC-8 aircraft during the Intercontinental Chemical Transport Experiment-A (INTEX-A). This mission, which was conducted mainly over North America and the western Atlantic Ocean in summer 2004, was an excellent test of atmospheric oxidation chemistry. The HOx results from INTEX-A are compared to those from previous campaigns and to results for other related measurements from INTEX-A. Throughout the troposphere, observed OH was generally 0.95 of modeled OH; below 8 km, observed HO_2 was generally 1.20 of modeled HO_2. This observed-to-modeled comparison is similar to that for TRACE-P, another midlatitude study for which the median observed-to-modeled ratio was 1.08 for OH and 1.34 for HO_2, and to that for PEM-TB, a tropical study for which the median observed-to-modeled ratio was 1.17 for OH and 0.97 for HO_2. HO_2 behavior above 8 km was markedly different. The observed-to-modeled HO_2 ratio increased from \u223c1.2 at 8 km to \u223c3 at 11 km with the observed-to-modeled ratio correlating with NO. Above 8 km, the observed-to-modeled HO_2 and observed NO were both considerably greater than observations from previous campaigns. In addition, the observed-to-modeled HO_2/OH, which is sensitive to cycling reactions between OH and HO_2, increased from \u223c1.5 at 8 km to almost 3.5 at 11 km. These discrepancies suggest a large unknown HO_x source and additional reactants that cycle HO_x from OH to HO_2. In the continental planetary boundary layer, the observed-to-modeled OH ratio increased from 1 when isoprene was less than 0.1 ppbv to over 4 when isoprene was greater than 2 ppbv, suggesting that forests throughout the United States are emitting unknown HO_x sources. Progress in resolving these discrepancies requires a focused research activity devoted to further examination of possible unknown OH sinks and HO_x sources.", "date": "2008-03-16", "date_type": "published", "publication": "Journal of Geophysical Research D", "volume": "113", "number": "D5", "publisher": "American Geophysical Union", "pagerange": "Art. No. D05310", "id_number": "CaltechAUTHORS:20140702-102532813", "issn": "0148-0227", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140702-102532813", "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": "10.1029/2007JD009166", "primary_object": { "basename": "jgrd14262-sup-0001-t01.txt", "url": "https://authors.library.caltech.edu/records/dhbgx-6st36/files/jgrd14262-sup-0001-t01.txt" }, "related_objects": [ { "basename": "jgrd14262.pdf", "url": "https://authors.library.caltech.edu/records/dhbgx-6st36/files/jgrd14262.pdf" } ], "resource_type": "article", "pub_year": "2008", "author_list": "Ren, Xinrong; Olson, Jennifer R.; et el." }, { "id": "https://authors.library.caltech.edu/records/7a9rv-xmr34", "eprint_id": 12276, "eprint_status": "archive", "datestamp": "2023-08-22 10:42:56", "lastmod": "2023-10-17 16:39:28", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Heald-C-L", "name": { "family": "Heald", "given": "C. L." } }, { "id": "Goldstein-Allen-H", "name": { "family": "Goldstein", "given": "A. H." }, "orcid": "0000-0003-4014-4896" }, { "id": "Allan-J-D", "name": { "family": "Allan", "given": "J. D." } }, { "id": "Aiken-A-C", "name": { "family": "Aiken", "given": "A. C." } }, { "id": "Apel-E", "name": { "family": "Apel", "given": "E." } }, { "id": "Atlas-E-L", "name": { "family": "Atlas", "given": "E. L." }, "orcid": "0000-0003-3847-5346" }, { "id": "Baker-A-K", "name": { "family": "Baker", "given": "A. K." } }, { "id": "Bates-T-S", "name": { "family": "Bates", "given": "T. S." } }, { "id": "Beyersdorf-A-J", "name": { "family": "Beyersdorf", "given": "A. J." }, "orcid": "0000-0002-4496-2557" }, { "id": "Blake-D-R", "name": { "family": "Blake", "given": "D. R." } }, { "id": "Campos-T", "name": { "family": "Campos", "given": "T." } }, { "id": "Coe-H", "name": { "family": "Coe", "given": "H." } }, { "id": "Crounse-John-D", "name": { "family": "Crounse", "given": "J. D." }, "orcid": "0000-0001-5443-729X" }, { "id": "DeCarlo-Peter-F", "name": { "family": "DeCarlo", "given": "P. F." }, "orcid": "0000-0001-6385-7149" }, { "id": "de-Gouw-Joost-A", "name": { "family": "de Gouw", "given": "J. A." }, "orcid": "0000-0002-0385-1826" }, { "id": "Dunlea-E-J", "name": { "family": "Dunlea", "given": "E. J." } }, { "id": "Flocke-F-M", "name": { "family": "Flocke", "given": "F. M." } }, { "id": "Fried-A", "name": { "family": "Fried", "given": "A." } }, { "id": "Goldan-P", "name": { "family": "Goldan", "given": "P." } }, { "id": "Griffin-R-J", "name": { "family": "Griffin", "given": "R. J." } }, { "id": "Herndon-S-C", "name": { "family": "Herndon", "given": "S. C." } }, { "id": "Holloway-J-S", "name": { "family": "Holloway", "given": "J. S." } }, { "id": "Holzinger-R", "name": { "family": "Holzinger", "given": "R." } }, { "id": "Jimenez-Jos\u00e9-L", "name": { "family": "Jimenez", "given": "J. L." }, "orcid": "0000-0001-6203-1847" }, { "id": "Junkermann-W", "name": { "family": "Junkermann", "given": "W." } }, { "id": "Kuster-W-C", "name": { "family": "Kuster", "given": "W. C." } }, { "id": "Lewis-A-C", "name": { "family": "Lewis", "given": "A. C." } }, { "id": "Meinardi-S", "name": { "family": "Meinardi", "given": "S." } }, { "id": "Millet-D-B", "name": { "family": "Millet", "given": "D. B." } }, { "id": "Onasch-T-B", "name": { "family": "Onasch", "given": "T." } }, { "id": "Polidori-A", "name": { "family": "Polidori", "given": "A." } }, { "id": "Quinn-P-K", "name": { "family": "Quinn", "given": "P. K." } }, { "id": "Riemer-D-D", "name": { "family": "Riemer", "given": "D. D." } }, { "id": "Roberts-J-M", "name": { "family": "Roberts", "given": "J. M." } }, { "id": "Salcedo-D", "name": { "family": "Salcedo", "given": "D." } }, { "id": "Sive-B", "name": { "family": "Sive", "given": "B." } }, { "id": "Swanson-A-L", "name": { "family": "Swanson", "given": "A. L." } }, { "id": "Talbot-R-W", "name": { "family": "Talbot", "given": "R." } }, { "id": "Warneke-C", "name": { "family": "Warneke", "given": "C." } }, { "id": "Weber-R-J", "name": { "family": "Weber", "given": "R. J." } }, { "id": "Weibring-P", "name": { "family": "Weibring", "given": "P." } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Wittig-A-E", "name": { "family": "Wittig", "given": "A. E." } }, { "id": "Zhang-R", "name": { "family": "Zhang", "given": "R." } }, { "id": "Zheng-J", "name": { "family": "Zheng", "given": "J." } }, { "id": "Zheng-W", "name": { "family": "Zheng", "given": "W." } } ] }, "title": "Total Observed Organic Carbon (TOOC): A synthesis of North American observations", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 Author(s) 2007. This work is distributed under the Creative Commons Attribution 3.0 License. \n\nReceived: 26 October 2007 \u2013 Accepted: 16 November 2007 \u2013 Published: 13 December 2007. \n\nThis work was supported by the NOAA Postdoctoral Program in Climate and Global Change, administered by the University Corporation for Atmospheric Research. Field measurements were supported by NOAA (under grants RA133R05SE4459, RA133R04SE0368, NA17RP2632, NA03OAR4600122, NA04OAR4600154 and NA05OAR4600189) NSF (under grants ATM-0449815 and ATM-0513116) and NASA (under grant NNG06GB03G). We thank B. Lerner for providing the CO observations aboard the R/V R. Brown, M. Evans for providing the BAe-146 merged data, R. Cohen and J. Fry for useful discussions and gratefully acknowledge core data from the BAe 146 aircraft provided by the UK Facility for Airborne Atmospheric Measurements.\n\nPublished - HEAacpd07.pdf
", "abstract": "Measurements of organic carbon compounds in both the gas and particle phases measured upwind, over and downwind of North America are synthesized to examine the total observed organic carbon (TOOC) over this region. These include measurements made aboard the NOAA WP-3 and BAe-146 aircraft, the NOAA research vessel Ronald H. Brown, and at the Thompson Farm and Chebogue Point surface sites during the summer 2004 ICARTT campaign. Both winter and summer 2002 measurements during the Pittsburgh Air Quality Study are also included. Lastly, the spring 2002 observations at Trinidad Head, CA, surface measurements made in March 2006 in Mexico City and coincidentally aboard the C-130 aircraft during the MILAGRO campaign and later during the IMPEX campaign off the northwestern United States are incorporated. Concentrations of TOOC in these datasets span more than two orders of magnitude. The daytime mean TOOC ranges from 4.0 to 456 \u03bcgC m^\u22123 from the cleanest site (Trinidad Head) to the most polluted (Mexico City). Organic aerosol makes up 3\u201317% of this mean TOOC, with highest fractions reported over the northeastern United States, where organic aerosol can comprise up to 50% of TOOC. Carbon monoxide concentrations explain 46 to 86% of the variability in TOOC, with highest TOOC/CO slopes in regions with fresh anthropogenic influence, where we also expect the highest degree of mass closure for TOOC. Correlation with isoprene, formaldehyde, methyl vinyl ketene and methacrolein also indicates that biogenic activity contributes substantially to the variability of TOOC, yet these tracers of biogenic oxidation sources do not explain the variability in organic aerosol observed over North America. We highlight the critical need to develop measurement techniques to routinely detect total gas phase VOCs, and to deploy comprehensive suites of TOOC instruments in diverse environments to quantify the ambient evolution of organic carbon from source to sink.", "date": "2007-12-13", "date_type": "published", "publication": "Atmospheric Chemistry and Physics Discussions", "volume": "7", "number": "6", "publisher": "European Geosciences Union", "pagerange": "17825-17871", "id_number": "CaltechAUTHORS:HEAacpd07", "issn": "1680-7367", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:HEAacpd07", "rights": "This work is distributed under the Creative Commons Attribution 3.0 License.", "funders": { "items": [ { "agency": "National Oceanic and Atmospheric Administration (NOAA)", "grant_number": "RA133R05SE4459" }, { "agency": "National Oceanic and Atmospheric Administration (NOAA)", "grant_number": "RA133R04SE0368" }, { "agency": "National Oceanic and Atmospheric Administration (NOAA)", "grant_number": "NA17RP2632" }, { "agency": "National Oceanic and Atmospheric Administration (NOAA)", "grant_number": "NA03OAR4600122" }, { "agency": "National Oceanic and Atmospheric Administration (NOAA)", "grant_number": "NA04OAR4600154" }, { "agency": "National Oceanic and Atmospheric Administration (NOAA)", "grant_number": "NA05OAR4600189" }, { "agency": "NSF", "grant_number": "ATM-0449815" }, { "agency": "NSF", "grant_number": "ATM-0513116" }, { "agency": "NASA", "grant_number": "NNG06GB03G" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/acp-8-2007-2008", "primary_object": { "basename": "HEAacpd07.pdf", "url": "https://authors.library.caltech.edu/records/7a9rv-xmr34/files/HEAacpd07.pdf" }, "resource_type": "article", "pub_year": "2007", "author_list": "Heald, C. L.; Goldstein, A. H.; et el." }, { "id": "https://authors.library.caltech.edu/records/4a3pd-j1044", "eprint_id": 9268, "eprint_status": "archive", "datestamp": "2023-08-22 10:30:37", "lastmod": "2023-10-23 17:38:28", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Peters-W", "name": { "family": "Peters", "given": "Wouter" }, "orcid": "0000-0001-8166-2070" }, { "id": "Jacobson-A-R", "name": { "family": "Jacobson", "given": "Andrew R." } }, { "id": "Sweeney-C", "name": { "family": "Sweeney", "given": "Colm" }, "orcid": "0000-0001-9568-0050" }, { "id": "Andrews-A-E", "name": { "family": "Andrews", "given": "Arlyn E." }, "orcid": "0000-0002-8552-3999" }, { "id": "Conway-T-J", "name": { "family": "Conway", "given": "Thomas J." } }, { "id": "Massarle-K", "name": { "family": "Massarle", "given": "Kenneth" } }, { "id": "Miller-J-B", "name": { "family": "Miller", "given": "John B." } }, { "id": "Bruhwiler-L-M-P", "name": { "family": "Bruhwiler", "given": "Lori M. P." } }, { "id": "P\u00e9tron-G", "name": { "family": "P\u00e9tron", "given": "Gabrielle" } }, { "id": "Hirsch-A-I", "name": { "family": "Hirsch", "given": "Adam I." } }, { "id": "Worthy-D-E-J", "name": { "family": "Worthy", "given": "Douglas E. J." } }, { "id": "van-der-Werf-G-R", "name": { "family": "van der Werf", "given": "Guido R." } }, { "id": "Randerson-J-T", "name": { "family": "Randerson", "given": "James T." }, "orcid": "0000-0001-6559-7387" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Krol-M-C", "name": { "family": "Krol", "given": "Maarten C." } }, { "id": "Tans-P-P", "name": { "family": "Tans", "given": "Pieter P." } } ] }, "title": "An atmospheric perspective on North American carbon dioxide exchange: CarbonTracker", "ispublished": "pub", "full_text_status": "public", "keywords": "carbon cycle | greenhouse gases | data assimilation | biogeochemistry | atmospheric composition", "note": "\u00a9 2007 National Academy of Sciences of the USA. Freely available online through the PNAS open access option. \n\nCommunicated by A. R. Ravishankara, National Oceanic and Atmospheric Administration, Boulder, CO, September 27, 2007 (received for review May 23, 2007). \n\nWe thank Taro Takahashi, Greg Marland, T. J. Blasing, Tris West, Jerry Olson, and the EDGAR consortium for contributing data sets used to complete this study. Development of the GFED2 fire emissions was supported by National Aeronautics and Space Administration Grant NNG04GK496. The column CO2 observations at Park Falls were obtained with support from National Aeronautics and Space Administration Grant NNG05GD07G. CarbonTracker is a National Oceanic and Atmospheric Administration contribution to the North American Carbon Program. \n\nAuthor contributions: P.P.T. designed research; C.S., A.E.A., T.J.C., D.E.J.W., G.R.v.d.W., J.T.R., and P.O.W. contributed data; A.R.J., K.M., J.B.M., L.M.P.B., G.P., A.I.H., and M.C.K. performed research; and W.P. wrote the paper. \n\nThe authors declare no conflict of interest. \n\nThis article contains supporting information online at www.pnas.org/cgi/content/full/0708986104/DC1.\n\nPublished - PETpnas07.pdf
Supplemental Material - PETpnas07appendix.pdf
", "abstract": "We present an estimate of net CO2 exchange between the terrestrial biosphere and the atmosphere across North America for every week in the period 2000 through 2005. This estimate is derived from a set of 28,000 CO2 mole fraction observations in the global atmosphere that are fed into a state-of-the-art data assimilation system for CO2 called CarbonTracker. By design, the surface fluxes produced in CarbonTracker are consistent with the recent history of CO2 in the atmosphere and provide constraints on the net carbon flux independent from national inventories derived from accounting efforts. We find the North American terrestrial biosphere to have absorbed \u20130.65 PgC/yr (1 petagram = 10^15 g; negative signs are used for carbon sinks) averaged over the period studied, partly offsetting the estimated 1.85 PgC/yr release by fossil fuel burning and cement manufacturing. Uncertainty on this estimate is derived from a set of sensitivity experiments and places the sink within a range of \u20130.4 to \u20131.0 PgC/yr. The estimated sink is located mainly in the deciduous forests along the East Coast (32%) and the boreal coniferous forests (22%). Terrestrial uptake fell to \u20130.32 PgC/yr during the large-scale drought of 2002, suggesting sensitivity of the contemporary carbon sinks to climate extremes. CarbonTracker results are in excellent agreement with a wide collection of carbon inventories that form the basis of the first North American State of the Carbon Cycle Report (SOCCR), to be released in 2007. All CarbonTracker results are freely available at http://carbontracker.noaa.gov.", "date": "2007-11-27", "date_type": "published", "publication": "Proceedings of the National Academy of Sciences of the United States of America", "volume": "104", "number": "48", "publisher": "National Academy of Sciences", "pagerange": "18925-18930", "id_number": "CaltechAUTHORS:PETpnas07", "issn": "0027-8424", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:PETpnas07", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "pmcid": "PMC2141884", "primary_object": { "basename": "PETpnas07.pdf", "url": "https://authors.library.caltech.edu/records/4a3pd-j1044/files/PETpnas07.pdf" }, "related_objects": [ { "basename": "PETpnas07appendix.pdf", "url": "https://authors.library.caltech.edu/records/4a3pd-j1044/files/PETpnas07appendix.pdf" } ], "resource_type": "article", "pub_year": "2007", "author_list": "Peters, Wouter; Jacobson, Andrew R.; et el." }, { "id": "https://authors.library.caltech.edu/records/64eav-56p04", "eprint_id": 46643, "eprint_status": "archive", "datestamp": "2023-08-22 10:24:47", "lastmod": "2023-10-26 19:54:05", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Yokelson-R-J", "name": { "family": "Yokelson", "given": "R. J." }, "orcid": "0000-0002-8415-6808" }, { "id": "Urbanski-S-P", "name": { "family": "Urbanski", "given": "S. P." } }, { "id": "Atlas-E-L", "name": { "family": "Atlas", "given": "E. L." }, "orcid": "0000-0003-3847-5346" }, { "id": "Toohey-D-W", "name": { "family": "Toohey", "given": "D. W." }, "orcid": "0000-0003-2853-1068" }, { "id": "Alvarado-E-C", "name": { "family": "Alvarado", "given": "E. C." } }, { "id": "Crounse-J-D", "name": { "family": "Crounse", "given": "J. D." }, "orcid": "0000-0001-5443-729X" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Fisher-M-E-EnvSci", "name": { "family": "Fisher", "given": "M. E." } }, { "id": "Wold-C-E", "name": { "family": "Wold", "given": "C. E." } }, { "id": "Campos-T-L", "name": { "family": "Campos", "given": "T. L." } }, { "id": "Adachi-K", "name": { "family": "Adachi", "given": "K." } }, { "id": "Buseck-P-R", "name": { "family": "Buseck", "given": "P. R." } }, { "id": "Hao-W-M", "name": { "family": "Hao", "given": "W. M." } } ] }, "title": "Emissions from forest fires near Mexico City", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2007 Author(s). This work is licensed under a Creative Commons License. \n\nReceived: 19 April 2007. Published in Atmos. Chem. Phys. Discuss.: 16 May 2007 Revised: 14 August 2007, Accepted: 27 October 2007, Published: 9 November 2007. \n\nThe authors thank Eric Hintsa and NSF for emergency supplemental funding that made it possible for ASU, U Miami, and U Colorado to conduct measurements on the Twin\nOtter. We thank the Twin Otter pilots E. Thompson, G. Moore,\nJ. Stright, A. Knobloch, and mechanic K. Bailey. Special thanks go to S. Madronich, L. Molina, and J. Meitin for their dedication to making the MILAGRO campaign a success for all. The University of Montana, the planned fire, and the airborne research was supported largely by NSF grant ATM-0513055. Yokelson was also supported by the Rocky Mountain Research Station, Forest Service, U.S. Department of Agriculture (agreement 03-UV-11222049-046). The USFS science team and partial support for the airborne research was provided by the NASA North American Carbon Plan (NNHO5AA86I). Participation by Arizona State University was supported by NSF grant ATM-0531926. Electron Microscopy was performed at the John M. Cowley Center for High Resolution Microscopy at Arizona State University. Support to\nthe University of Miami was provided by NSF (ATM 0511820).\nX. Zhu and L. Pope provided excellent technical support for the canister trace gas analyses. Support for operation of the Caltech CIMS instrument was provided by NASA (NNG04GA59G) and by EPA-STAR support for J. Crounse. We also thank the fire staff of Mexico's Comision Nacional Forestal in the states of Morelos, Mexico, Distrito Federal, and the Guadalajara Headquarters for the execution of the prescribed fire in the state of Morelos and for logistical support to conduct post-fire assessment of several fires of opportunity flown by the Twin Otter aircraft. Edited by: L. Molina\n\nPublished - acp-7-5569-2007.pdf
", "abstract": "The emissions of NO_x (defined as NO (nitric oxide) + NO_2 (nitrogen dioxide)) and hydrogen cyanide (HCN), per unit amount of fuel burned, from fires in the pine forests that dominate the mountains surrounding Mexico City (MC) are about 2 times higher than normally observed for forest burning. The ammonia (NH_3) emissions are about average for forest burning. The upper limit for the mass ratio of NO_x to volatile organic compounds (VOC) for these MC-area mountain fires was ~0.38, which is similar to the NO_x/VOC ratio in the MC urban area emissions inventory of 0.34, but much larger than the NO_x/VOC ratio for tropical forest fires in Brazil (~0.068). The nitrogen enrichment in the fire emissions may be due to deposition of nitrogen-containing pollutants in the outflow from the MC urban area. This effect may occur worldwide wherever biomass burning coexists with large urban areas (e.g. the tropics, southeastern US, Los Angeles Basin). The molar emission ratio of HCN to carbon monoxide (CO) for the mountain fires was 0.012\u00b10.007, which is 2\u20139 times higher than widely used literature values for biomass burning. The ambient molar ratio HCN/CO in the MC-area outflow is about 0.003\u00b10.0003. Thus, if only mountain fires emit significant amounts of HCN, these fires may be contributing about 25% of the CO production in the MC-area (~98\u2013100 W and 19\u201320 N). Comparing the PM_(10)/CO and PM_(2.5)/CO mass ratios in the MC Metropolitan Area emission inventory (0.0115 and 0.0037) to the PM1/CO mass ratio for the mountain fires (0.133) then suggests that these fires could produce as much as ~79\u201392% of the primary fine particle mass generated in the MC-area. Considering both the uncertainty in the HCN/CO ratios and secondary aerosol formation in the urban and fire emissions implies that about 50\u00b130% of the \"aged\" fine particle mass in the March 2006 MC-area outflow could be from these fires.", "date": "2007-11-09", "date_type": "published", "publication": "Atmospheric Chemistry and Physics", "volume": "7", "number": "21", "publisher": "European Geosciences Union", "pagerange": "5569-5584", "id_number": "CaltechAUTHORS:20140702-135853774", "issn": "1680-7316", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140702-135853774", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "ATM-0513055" }, { "agency": "Rocky Mountain Research Station, US Forest Service" }, { "agency": "Department of Agriculture (USDA)", "grant_number": "03-UV-11222049-046" }, { "agency": "NASA", "grant_number": "NNHO5AA86I" }, { "agency": "NSF", "grant_number": "ATM-0531926" }, { "agency": "NSF", "grant_number": "ATM 0511820" }, { "agency": "NASA", "grant_number": "NNG04GA59G" }, { "agency": "Environmental Protection Agency (EPA)" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/acp-7-5569-2007", "primary_object": { "basename": "acp-7-5569-2007.pdf", "url": "https://authors.library.caltech.edu/records/64eav-56p04/files/acp-7-5569-2007.pdf" }, "resource_type": "article", "pub_year": "2007", "author_list": "Yokelson, R. J.; Urbanski, S. P.; et el." }, { "id": "https://authors.library.caltech.edu/records/4xw5d-ztz34", "eprint_id": 9306, "eprint_status": "archive", "datestamp": "2023-08-22 10:12:51", "lastmod": "2023-10-16 22:08:07", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Ng-Nga-Lee", "name": { "family": "Ng", "given": "N. L." }, "orcid": "0000-0001-8460-4765" }, { "id": "Chhabra-Puneet-S", "name": { "family": "Chhabra", "given": "P. S." } }, { "id": "Chan-Arthur-W-H", "name": { "family": "Chan", "given": "A. W. H." }, "orcid": "0000-0001-7392-4237" }, { "id": "Surratt-Jason-D", "name": { "family": "Surratt", "given": "J. D." }, "orcid": "0000-0002-6833-1450" }, { "id": "Kroll-Jesse-H", "name": { "family": "Kroll", "given": "J. H." }, "orcid": "0000-0002-6275-521X" }, { "id": "Kwan-Alan-J", "name": { "family": "Kwan", "given": "A. J." } }, { "id": "McCabe-David-C", "name": { "family": "McCabe", "given": "D. C." } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Sorooshian-Armin", "name": { "family": "Sorooshian", "given": "A." }, "orcid": "0000-0002-2243-2264" }, { "id": "Murphy-Shane-M", "name": { "family": "Murphy", "given": "S. M." }, "orcid": "0000-0002-6415-2607" }, { "id": "Dalleska-Nathan-F", "name": { "family": "Dalleska", "given": "N. F." }, "orcid": "0000-0002-2059-1587" }, { "id": "Flagan-R-C", "name": { "family": "Flagan", "given": "R. C." }, "orcid": "0000-0001-5690-770X" }, { "id": "Seinfeld-J-H", "name": { "family": "Seinfeld", "given": "J. H." }, "orcid": "0000-0003-1344-4068" } ] }, "title": "Effect of NO\u2093 level on secondary organic aerosol (SOA) formation from the photooxidation of terpenes", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 Author(s) 2007. This work is licensed under a Creative Commons License. Published by Copernicus Publications on behalf of the European Geosciences Union. \n\nReceived: 7 June 2007 \u2013 Published in Atmos. Chem. Phys. Discuss.: 12 July 2007. Revised: 14 September 2007 \u2013 Accepted: 29 September 2007 \u2013 Published: 8 October 2007. \n\nThis research was funded by U.S. Department of Energy Biological and Environmental Research Program grant DE-FG02-05ER63983. This material is based in part on work supported by the National Science Foundation (NSF) under grant ATM-0432377. The Waters LCT Premier XT time-of-flight mass spectrometer interfaced to a Waters UPLC system was purchased in 2006 with a grant from the National Science Foundation, Chemistry Research Instrumentation and Facilities Program (CHE-0541745). The LCQ Ion Trap mass spectrometer was purchased in 1997 with funds from the National Science Foundation through the CRIF program (CHE-9709233). J.D. Surratt is supported in part by the U.S. EPA under the STAR Graduate Fellowship Program. A.J. Kwan acknowledges the support of a NSF graduate research fellowship. The authors would like to thank M. Shahgohli of the Chemistry Department at Caltech for her useful communications regarding high-resolution mass spectrometry.\n\nPublished - NGNacp07b.pdf
", "abstract": "Secondary organic aerosol (SOA) formation from the photooxidation of one monoterpene (\u03b1-pinene) and two sesquiterpenes (longifolene and aromadendrene) is investigated in the Caltech environmental chambers. The effect of NOx on SOA formation for these biogenic hydrocarbons is evaluated by performing photooxidation experiments under varying NO\u2093 conditions. The NO\u2093 dependence of \u03b1-pinene SOA formation follows the same trend as that observed previously for a number of SOA precursors, including isoprene, in which SOA yield (defined as the ratio of the mass of organic aerosol formed to the mass of parent hydrocarbon reacted) decreases as NO\u2093 level increases. The NO\u2093 dependence of SOA yield for the sesquiterpenes, longifolene and aromadendrene, however, differs from that determined for isoprene and \u03b1-pinene; the aerosol yield under high-NO\u2093 conditions substantially exceeds that under low-NO\u2093 conditions. The reversal of the NO\u2093 dependence of SOA formation for the sesquiterpenes is consistent with formation of relatively low-volatility organic nitrates, and/or the isomerization of large alkoxy radicals leading to less volatile products. Analysis of the aerosol chemical composition for longifolene confirms the presence of organic nitrates under high-NO\u2093 conditions. Consequently the formation of SOA from certain biogenic hydrocarbons such as sesquiterpenes (and possibly large anthropogenic hydrocarbons as well) may be more efficient in polluted air.", "date": "2007-10-08", "date_type": "published", "publication": "Atmospheric Chemistry and Physics", "volume": "7", "number": "19", "publisher": "European Geosciences Union", "pagerange": "5159-5174", "id_number": "CaltechAUTHORS:NGNacp07b", "issn": "1680-7316", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:NGNacp07b", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-FG02-05ER63983" }, { "agency": "NSF", "grant_number": "ATM-0432377" }, { "agency": "NSF", "grant_number": "CHE-0541745" }, { "agency": "NSF", "grant_number": "CHE-9709233" }, { "agency": "Environmental Protection Agency (EPA)" }, { "agency": "NSF Graduate Research Fellowship" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/acp-7-5159-2007", "primary_object": { "basename": "NGNacp07b.pdf", "url": "https://authors.library.caltech.edu/records/4xw5d-ztz34/files/NGNacp07b.pdf" }, "resource_type": "article", "pub_year": "2007", "author_list": "Ng, N. L.; Chhabra, P. S.; et el." }, { "id": "https://authors.library.caltech.edu/records/bdqz2-7hb40", "eprint_id": 8651, "eprint_status": "archive", "datestamp": "2023-08-22 09:32:34", "lastmod": "2023-10-23 16:21:25", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Keppel-Aleka-G", "name": { "family": "Keppel-Aleka", "given": "Gretchen" } }, { "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": "Deutscher-N-M", "name": { "family": "Deutscher", "given": "Nicholas M." }, "orcid": "0000-0002-2906-2577" } ] }, "title": "Reducing the impact of source brightness fluctuations on spectra obtained by Fourier-transform spectrometry", "ispublished": "pub", "full_text_status": "public", "keywords": "Atmospheric composition, Continuous optical signal processing", "note": "\u00a9 2007 Optical Society of America \n\nReceived 29 January 2007; revised 19 March 2007; accepted 22 March 2007; posted 23 March 2007 (Doc. ID 79475); published 6 July 2007 \n\nThe authors thank D. Griffith and G. Bryant for their role in data acquisition at the Darwin FTS site. J.-F. Blavier is gratefully acknowledged for helpful discussions. This analysis was supported by a grant from NASA (NNGO5-GD07G). The Darwin FTS was developed for the OCO project at NASA JPL; G. Keppel-Aleks acknowledges support from the NSF Graduate Fellowship Program.\n\nPublished - KEPao07.pdf
", "abstract": "We present a method to reduce the impact of source brightness fluctuations (SBFs) on spectra recorded by Fourier-transform spectrometry (FTS). Interferograms are recorded without AC coupling of the detector signal (DC mode). The SBF are determined by low-pass filtering of the DC interferograms, which are then reweighted by the low-pass, smoothed signal. Atmospheric solar absorption interferograms recorded in DC mode have been processed with and without this technique, and we demonstrate its efficacy in producing more consistent retrievals of atmospheric composition. We show that the reweighting algorithm improves retrievals from interferograms subject to both gray and nongray intensity fluctuations, making the algorithm applicable to atmospheric data contaminated by significant amounts of aerosol or cloud cover.", "date": "2007-07-20", "date_type": "published", "publication": "Applied Optics", "volume": "46", "number": "21", "publisher": "Optical Society of America", "pagerange": "4774-4779", "id_number": "CaltechAUTHORS:KEPao07", "issn": "0003-6935", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:KEPao07", "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": "10.1364/AO.46.004774", "primary_object": { "basename": "KEPao07.pdf", "url": "https://authors.library.caltech.edu/records/bdqz2-7hb40/files/KEPao07.pdf" }, "resource_type": "article", "pub_year": "2007", "author_list": "Keppel-Aleka, Gretchen; Toon, Geoffrey C.; et el." }, { "id": "https://authors.library.caltech.edu/records/f9ps5-01334", "eprint_id": 46636, "eprint_status": "archive", "datestamp": "2023-08-22 09:22:02", "lastmod": "2023-10-26 19:53:42", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Liang-Qing", "name": { "family": "Liang", "given": "Q." }, "orcid": "0000-0002-8430-0515" }, { "id": "Jaegl\u00e9-L", "name": { "family": "Jaegl\u00e9", "given": "L." } }, { "id": "Hudman-R-C", "name": { "family": "Hudman", "given": "R. C." } }, { "id": "Turquety-S", "name": { "family": "Turquety", "given": "S." } }, { "id": "Jacob-D-J", "name": { "family": "Jacob", "given": "D. J." }, "orcid": "0000-0002-6373-3100" }, { "id": "Avery-M-A", "name": { "family": "Avery", "given": "M. A." } }, { "id": "Browell-E-V", "name": { "family": "Browell", "given": "E. V." } }, { "id": "Sachse-G-W", "name": { "family": "Sachse", "given": "G. W." } }, { "id": "Blake-D-R", "name": { "family": "Blake", "given": "D. R." } }, { "id": "Brune-W", "name": { "family": "Brune", "given": "W." } }, { "id": "Ren-Xinrong", "name": { "family": "Ren", "given": "X." } }, { "id": "Cohen-R-C", "name": { "family": "Cohen", "given": "R. C." }, "orcid": "0000-0001-6617-7691" }, { "id": "Dibb-J-E", "name": { "family": "Dibb", "given": "J. E." }, "orcid": "0000-0003-3096-7709" }, { "id": "Fried-A", "name": { "family": "Fried", "given": "A." } }, { "id": "Fuelberg-H", "name": { "family": "Fuelberg", "given": "H." } }, { "id": "Porter-M", "name": { "family": "Porter", "given": "M." } }, { "id": "Heikes-B-G", "name": { "family": "Heikes", "given": "B. G." } }, { "id": "Huey-G", "name": { "family": "Huey", "given": "G." } }, { "id": "Singh-H-B", "name": { "family": "Singh", "given": "H. B." } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "Summertime influence of Asian pollution in the free troposphere over North America", "ispublished": "pub", "full_text_status": "public", "keywords": "intercontinental transport; Asia; ozone", "note": "\u00a9 2007 American Geophysical Union. \n\nReceived 15 August 2006; revised 29 November 2006; accepted 11 January 2007; article first published online 11 May 2007. \n\nWork at the University of Washington was supported by funding from the National Science Foundation (ATM 0238530) and NASA. \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 - jgrd13468.pdf
Supplemental Material - jgrd13468-sup-0001-t01.txt
Supplemental Material - jgrd13468-sup-0002-t02.txt
Supplemental Material - jgrd13468-sup-0003-t03.txt
Supplemental Material - jgrd13468-sup-0004-t04.txt
", "abstract": "We analyze aircraft observations obtained during INTEX-A (1 July to 14 August 2004) to examine the summertime influence of Asian pollution in the free troposphere over North America. By applying correlation analysis and principal component analysis (PCA) to the observations between 6 and 12 km, we find dominant influences from recent convection and lightning (13% of observations), Asia (7%), the lower stratosphere (7%), and boreal forest fires (2%), with the remaining 71% assigned to background. Asian air masses are marked by high levels of CO, O_3, HCN, PAN, C_2H_2, C_6H_6, methanol, and SO_4^(2\u2013). The partitioning of NO_y species in the Asian plumes is dominated by PAN (\u223c600 pptv), with varying NO_x/HNO_3 ratios in individual plumes, consistent with individual transit times of 3\u20139 days. Export of Asian pollution occurred in warm conveyor belts of midlatitude cyclones, deep convection, and in typhoons. Compared to Asian outflow measurements during spring, INTEX-A observations display lower levels of anthropogenic pollutants (CO, C_3H_8, C_2H_6, C_6H_6) due to shorter summer lifetimes; higher levels of biogenic tracers (methanol and acetone) because of a more active biosphere; and higher levels of PAN, NO_x, HNO_3, and O_3 reflecting active photochemistry, possibly enhanced by efficient NO_y export and lightning. The high \u0394O_3/\u0394CO ratio (0.76 mol/mol) in Asian plumes during INTEX-A is due to strong photochemical production and, in some cases, mixing with stratospheric air along isentropic surfaces. The GEOS-Chem global model captures the timing and location of the Asian plumes. However, it significantly underestimates the magnitude of observed enhancements in CO, O_3, PAN and NO_x.", "date": "2007-06-27", "date_type": "published", "publication": "Journal of Geophysical Research D", "volume": "112", "number": "D12", "publisher": "American Geophysical Union", "pagerange": "Art. No. D12S11", "id_number": "CaltechAUTHORS:20140702-110447278", "issn": "0148-0227", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140702-110447278", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "ATM-0238530" }, { "agency": "NASA" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2006JD007919", "primary_object": { "basename": "jgrd13468-sup-0002-t02.txt", "url": "https://authors.library.caltech.edu/records/f9ps5-01334/files/jgrd13468-sup-0002-t02.txt" }, "related_objects": [ { "basename": "jgrd13468-sup-0003-t03.txt", "url": "https://authors.library.caltech.edu/records/f9ps5-01334/files/jgrd13468-sup-0003-t03.txt" }, { "basename": "jgrd13468-sup-0004-t04.txt", "url": "https://authors.library.caltech.edu/records/f9ps5-01334/files/jgrd13468-sup-0004-t04.txt" }, { "basename": "jgrd13468.pdf", "url": "https://authors.library.caltech.edu/records/f9ps5-01334/files/jgrd13468.pdf" }, { "basename": "jgrd13468-sup-0001-t01.txt", "url": "https://authors.library.caltech.edu/records/f9ps5-01334/files/jgrd13468-sup-0001-t01.txt" } ], "resource_type": "article", "pub_year": "2007", "author_list": "Liang, Q.; Jaegl\u00e9, L.; et el." }, { "id": "https://authors.library.caltech.edu/records/s7v2j-90452", "eprint_id": 46629, "eprint_status": "archive", "datestamp": "2023-08-22 09:21:43", "lastmod": "2023-10-26 19:53:26", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Yang-Z", "name": { "family": "Yang", "given": "Z." } }, { "id": "Washenfelder-R-A", "name": { "family": "Washenfelder", "given": "R. A." }, "orcid": "0000-0002-8106-3702" }, { "id": "Keppel-Aleks-G", "name": { "family": "Keppel-Aleks", "given": "G." } }, { "id": "Krakauer-N-Y", "name": { "family": "Krakauer", "given": "N. Y." } }, { "id": "Randerson-J-T", "name": { "family": "Randerson", "given": "J. T." }, "orcid": "0000-0001-6559-7387" }, { "id": "Tans-P-P", "name": { "family": "Tans", "given": "P. P." } }, { "id": "Sweeney-C", "name": { "family": "Sweeney", "given": "C." }, "orcid": "0000-0001-9568-0050" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "New constraints on Northern Hemisphere growing season net flux", "ispublished": "pub", "full_text_status": "public", "keywords": "Northern Hemisphere; terrestrial carbon sink; net ecosystem exchange; column-averaged CO_2; aircraft profiles; inverse modeling", "note": "\u00a9 2007 American Geophysical Union. Received 5 March 2007; revised 27 April 2007; accepted 1 May 2007; article first published online 23 June 2007. We thank the TransCom 3 modeling community (K. Gurney, M. Prather, T. Maki, L. Bruhwiler, Y. Chen, R. Law, C. Yuen, S. Fan, M. Heimann, and D. Baker) for making the results of their simulations publicly available. This work was supported by a NASA\ngrant NNG05GD07G. N. Y. Krakauer was supported by Graduate Fellowships from both NASA Earth and Space Science and the Betty and Gordon Moore Foundation.\n\nPublished - grl23074.pdf
Supplemental Material - grl23074-sup-0001-readme.txt
Supplemental Material - grl23074-sup-0002-ts01.txt
Supplemental Material - grl23074-sup-0003-ts02.txt
Supplemental Material - grl23074-sup-0004-fs01.eps
Supplemental Material - grl23074-sup-0005-fs02.eps
Supplemental Material - grl23074-sup-0006-fs03.eps
Supplemental Material - grl23074-sup-0007-t01.txt
Supplemental Material - grl23074-sup-0008-t02.txt
", "abstract": "Observations of the column-averaged dry molar mixing ratio of CO_2 above both Park Falls, Wisconsin and Kitt Peak, Arizona, together with partial columns derived from aircraft profiles over Eurasia and North America are used to estimate the seasonal integral of net ecosystem exchange (NEE) between the atmosphere and the terrestrial biosphere in the Northern Hemisphere. We find that NEE is \u223c25% larger than predicted by the Carnegie Ames Stanford Approach (CASA) model. We show that the estimates of NEE may have been biased low by too weak vertical mixing in the transport models used to infer seasonal changes in Northern Hemisphere CO_2 mass from the surface measurements of CO_2 mixing ratio.", "date": "2007-06-23", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "34", "number": "12", "publisher": "American Geophysical Union", "pagerange": "Art. No. L12807", "id_number": "CaltechAUTHORS:20140702-100545630", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140702-100545630", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NNG05GD07G" }, { "agency": "NASA Graduate Fellowship" }, { "agency": "NASA Earth and Space Science Fellowship" }, { "agency": "Gordon and Betty Moore Foundation" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2007GL029742", "primary_object": { "basename": "grl23074-sup-0008-t02.txt", "url": "https://authors.library.caltech.edu/records/s7v2j-90452/files/grl23074-sup-0008-t02.txt" }, "related_objects": [ { "basename": "grl23074.pdf", "url": "https://authors.library.caltech.edu/records/s7v2j-90452/files/grl23074.pdf" }, { "basename": "grl23074-sup-0001-readme.txt", "url": "https://authors.library.caltech.edu/records/s7v2j-90452/files/grl23074-sup-0001-readme.txt" }, { "basename": "grl23074-sup-0002-ts01.txt", "url": "https://authors.library.caltech.edu/records/s7v2j-90452/files/grl23074-sup-0002-ts01.txt" }, { "basename": "grl23074-sup-0005-fs02.eps", "url": "https://authors.library.caltech.edu/records/s7v2j-90452/files/grl23074-sup-0005-fs02.eps" }, { "basename": "grl23074-sup-0006-fs03.eps", "url": "https://authors.library.caltech.edu/records/s7v2j-90452/files/grl23074-sup-0006-fs03.eps" }, { "basename": "grl23074-sup-0003-ts02.txt", "url": "https://authors.library.caltech.edu/records/s7v2j-90452/files/grl23074-sup-0003-ts02.txt" }, { "basename": "grl23074-sup-0004-fs01.eps", "url": "https://authors.library.caltech.edu/records/s7v2j-90452/files/grl23074-sup-0004-fs01.eps" }, { "basename": "grl23074-sup-0007-t01.txt", "url": "https://authors.library.caltech.edu/records/s7v2j-90452/files/grl23074-sup-0007-t01.txt" } ], "resource_type": "article", "pub_year": "2007", "author_list": "Yang, Z.; Washenfelder, R. A.; et el." }, { "id": "https://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.edu/records/dn0sv-byq60", "eprint_id": 7569, "eprint_status": "archive", "datestamp": "2023-08-22 08:31:59", "lastmod": "2023-10-23 19:32:14", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Roehl-C-M", "name": { "family": "Roehl", "given": "C. M." }, "orcid": "0000-0001-5383-8462" }, { "id": "Marka-Z", "name": { "family": "Marka", "given": "Z." } }, { "id": "Fry-J-L", "name": { "family": "Fry", "given": "J. L." } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "Near-UV photolysis cross sections of CH_3OOH and HOCH_2OOH determined via action spectroscopy", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 Author(s) 2007. This work is licensed under the Creative Commons Attribution-NonCommercial-ShareAlike 2.5 License. \n\nReceived: 18 October 2006 \u2013 Published in Atmos. Chem. Phys. Discuss.: 20 November 2006. Revised: 8 February 2007 \u2013 Accepted: 9 February 2007 \u2013 Published: 14 February 2007. \n\nThe authors thank the National Science Foundation (ATM-0432377) and the Massachusetts Institute of Technology, Air Quality Models Project (R824970-01-0) for support of this research.\n\nPublished - ROEacp07.pdf
", "abstract": "Knowledge of molecular photolysis cross sections is important for determining atmospheric lifetimes and fates of many species. A method and laser apparatus for measurement of these cross sections in the near-ultraviolet (UV) region is described. The technique is based on action spectroscopy, where the yield of a photodissociation product (in this case OH) is measured as a function of excitation energy. For compounds yielding OH, this method can be used to measure near-UV photodissociation cross section as low as 10\u221223 cm2 molecule\u22121. The method is applied to determine the photodissociation cross sections for methyl hydroperoxide (CH3OOH; MHP) and hydroxymethyl hydroperoxide (HOCH2OOH; HMHP) in the 305\u2013365 nm wavelength range. The measured cross sections are in good agreement with previous measurements of absorption cross sections.", "date": "2007-02-14", "date_type": "published", "publication": "Atmospheric Chemistry and Physics", "volume": "7", "number": "3", "publisher": "European Geosciences Union", "pagerange": "713-720", "id_number": "CaltechAUTHORS:ROEacp07", "issn": "1680-7316", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:ROEacp07", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "ATM-0432377" }, { "agency": "Environmental Protection Agency (EPA)", "grant_number": "R824970-01-0" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/acp-7-713-2007", "primary_object": { "basename": "ROEacp07.pdf", "url": "https://authors.library.caltech.edu/records/dn0sv-byq60/files/ROEacp07.pdf" }, "resource_type": "article", "pub_year": "2007", "author_list": "Roehl, C. M.; Marka, Z.; et el." }, { "id": "https://authors.library.caltech.edu/records/n2bne-ca073", "eprint_id": 46645, "eprint_status": "archive", "datestamp": "2023-08-22 08:27:00", "lastmod": "2023-10-26 19:54:12", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Bertram-T-H", "name": { "family": "Bertram", "given": "Timothy H." }, "orcid": "0000-0002-3026-7588" }, { "id": "Perring-A-E", "name": { "family": "Perring", "given": "Anne E." } }, { "id": "Wooldridge-P-J", "name": { "family": "Wooldridge", "given": "Paul J." } }, { "id": "Crounse-J-D", "name": { "family": "Crounse", "given": "John D." }, "orcid": "0000-0001-5443-729X" }, { "id": "Kwan-Alan-J", "name": { "family": "Kwan", "given": "Alan J." } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Scheuer-E", "name": { "family": "Scheuer", "given": "Eric" } }, { "id": "Dibb-J-E", "name": { "family": "Dibb", "given": "Jack" }, "orcid": "0000-0003-3096-7709" }, { "id": "Avery-M-A", "name": { "family": "Avery", "given": "Melody" } }, { "id": "Sachse-G-W", "name": { "family": "Sachse", "given": "Glen" } }, { "id": "Vay-S-A", "name": { "family": "Vay", "given": "Sthephanie A." } }, { "id": "Crawford-J-H", "name": { "family": "Crawford", "given": "James H." } }, { "id": "McNaughton-C-S", "name": { "family": "McNaughton", "given": "Cameron S." } }, { "id": "Clarke-A-D", "name": { "family": "Clarke", "given": "Antony" } }, { "id": "Pickering-K-E", "name": { "family": "Pickering", "given": "Kenneth E." } }, { "id": "Fuelberg-H", "name": { "family": "Fuelberg", "given": "Henry" } }, { "id": "Huey-G", "name": { "family": "Huey", "given": "Greg" } }, { "id": "Blake-D-R", "name": { "family": "Blake", "given": "Donald R." } }, { "id": "Singh-H-B", "name": { "family": "Singh", "given": "Hanwant B." } }, { "id": "Hall-S-R", "name": { "family": "Hall", "given": "Samuel R." }, "orcid": "0000-0002-2060-7112" }, { "id": "Shetter-R-E", "name": { "family": "Shetter", "given": "Richard E." } }, { "id": "Fried-A", "name": { "family": "Fried", "given": "Alan" } }, { "id": "Heikes-B-G", "name": { "family": "Heikes", "given": "Brian G." } }, { "id": "Cohen-R-C", "name": { "family": "Cohen", "given": "Ronald C." }, "orcid": "0000-0001-6617-7691" } ] }, "title": "Direct Measurements of the Convective Recycling of the Upper Troposphere", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2007 American Association for the Advancement of Science. \n\nReceived for publication 31 August 2006. Accepted for publication 19 December 2006. \n\nWe thank the flight and ground crews of the NASA DC-8 aircraft and the entire INTEX-NA science team for their contributions during the 2004 intensive field campaign; A. M. Thompson, I. Folkins, M. G. Lawrence, and D. Allen for helpful discussions; T. Kucsera for help with the GEOS-4 calculations; and W. H. Brune and X. Ren for OH and HO_2 data. NLDN data were collected by Vaisala-Thunderstorm and provided to the INTEX Science Team by the Global Hydrology Resource Center at NASA Marshall Space Flight Center. Work at UC Berkeley was supported by NASA grants NNG05GH196 and NAG5-13668. The\nINTEX-NA field program was supported by the NASA-ESE\nTropospheric Chemistry Program.\n\nSupplemental Material - Bertram.SOM.pdf
", "abstract": "We present a statistical representation of the aggregate effects of deep convection on the chemistry and dynamics of the upper troposphere (UT) based on direct aircraft observations of the chemical composition of the UT over the eastern United States and Canada during summer. These measurements provide unique observational constraints on the chemistry occurring downwind of convection and the rate at which air in the UT is recycled. These results provide quantitative measures that can be used to evaluate global climate and chemistry models.", "date": "2007-02-09", "date_type": "published", "publication": "Science", "volume": "315", "number": "5813", "publisher": "American Association for the Advancement of Science", "pagerange": "816-820", "id_number": "CaltechAUTHORS:20140702-144915836", "issn": "0036-8075", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140702-144915836", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NNG05GH196" }, { "agency": "NASA", "grant_number": "NAG5-13668" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1126/science.1134548", "primary_object": { "basename": "Bertram.SOM.pdf", "url": "https://authors.library.caltech.edu/records/n2bne-ca073/files/Bertram.SOM.pdf" }, "resource_type": "article", "pub_year": "2007", "author_list": "Bertram, Timothy H.; Perring, Anne E.; et el." }, { "id": "https://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.edu/records/xbxyv-1ag82", "eprint_id": 46615, "eprint_status": "archive", "datestamp": "2023-08-22 07:39:05", "lastmod": "2023-10-26 19:52:43", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Washenfelder-R-A", "name": { "family": "Washenfelder", "given": "R. A." }, "orcid": "0000-0002-8106-3702" }, { "id": "Toon-G-C", "name": { "family": "Toon", "given": "G. C." }, "orcid": "0000-0003-4174-7541" }, { "id": "Blavier-J-F-L", "name": { "family": "Blavier", "given": "J.-F." } }, { "id": "Yang-Z", "name": { "family": "Yang", "given": "Z." } }, { "id": "Allen-N-T", "name": { "family": "Allen", "given": "N. T." } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Vay-S-A", "name": { "family": "Vay", "given": "S. A." } }, { "id": "Matross-D-M", "name": { "family": "Matross", "given": "D. M." } }, { "id": "Daube-B-C-Jr", "name": { "family": "Daube", "given": "B. C." } } ] }, "title": "Carbon dioxide column abundances at the Wisconsin Tall Tower site", "ispublished": "pub", "full_text_status": "public", "keywords": "column; Total Carbon Column Observing Network; Fourier Transform Spectrometry", "note": "\u00a9 2006 American Geophysical Union. Received 6 February 2006; revised 12 May 2006; accepted 26 May 2006; article first published online 18 November 2006. We thank Jeffrey Ayers for maintaining the ground-based FTS laboratory in Park Falls, Wisconsin. We thank Arlyn Andrews and the NOAA CCGG for providing WLEF Tall Tower CO_2 measurements. Bruce Daube thanks Victoria Chow and Bhaswar Sen for their support in obtaining the balloon CO_2 profile. We thank Andrew Orr-Ewing for helpful discussions and providing PGOPHER model results for the O_2 7882 cm^(-1) band. R.A.W. acknowledges support from the National Science Foundation and the California Institute of Technology. This work was funded by NASA grant NAG5-12247 and NNG05-GD07G. Research\nat the Jet Propulsion Laboratory, California Institute of Technology, is performed under contract with NASA.\n\nPublished - jgrd12964.pdf
Supplemental Material - jgrd12964-sup-0001-t01.txt
", "abstract": "We have developed an automated observatory for measuring atmospheric column abundances of CO_2 and O_2 using near-infrared spectra of the Sun obtained with a high spectral resolution Fourier Transform Spectrometer (FTS). This is the first dedicated laboratory in a new network of ground-based observatories named the Total Carbon Column Observing Network. This network will be used for carbon cycle studies and validation of spaceborne column measurements of greenhouse gases. The observatory was assembled in Pasadena, California, and then permanently deployed to northern Wisconsin during May 2004. It is located in the heavily forested Chequamegon National Forest at the WLEF Tall Tower site, 12 km east of Park Falls, Wisconsin. Under clear sky conditions, \u223c0.1% measurement precision is demonstrated for the retrieved column CO_2 abundances. During the Intercontinental Chemical Transport Experiment\u2013North America and CO_2 Boundary Layer Regional Airborne Experiment campaigns in summer 2004, the DC-8 and King Air aircraft recorded eight in situ CO_2 profiles over the WLEF site. Comparison of the integrated aircraft profiles and CO_2 column abundances shows a small bias (\u223c2%) but an excellent correlation.", "date": "2006-11-27", "date_type": "published", "publication": "Journal of Geophysical Research D", "volume": "111", "number": "D22", "publisher": "American Geophysical Union", "pagerange": "Art. No. D22305", "id_number": "CaltechAUTHORS:20140702-071659164", "issn": "0148-0227", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140702-071659164", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF" }, { "agency": "Caltech" }, { "agency": "NASA", "grant_number": "NAG5-12247" }, { "agency": "NASA", "grant_number": "NNG05-GD07G" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2006JD007154", "primary_object": { "basename": "jgrd12964.pdf", "url": "https://authors.library.caltech.edu/records/xbxyv-1ag82/files/jgrd12964.pdf" }, "related_objects": [ { "basename": "jgrd12964-sup-0001-t01.txt", "url": "https://authors.library.caltech.edu/records/xbxyv-1ag82/files/jgrd12964-sup-0001-t01.txt" } ], "resource_type": "article", "pub_year": "2006", "author_list": "Washenfelder, R. A.; Toon, G. C.; et el." }, { "id": "https://authors.library.caltech.edu/records/hpzfj-8c316", "eprint_id": 6993, "eprint_status": "archive", "datestamp": "2023-09-13 16:50:41", "lastmod": "2023-10-23 20:39:21", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Roehl-C-M", "name": { "family": "Roehl", "given": "C. M." }, "orcid": "0000-0001-5383-8462" }, { "id": "Marka-Z", "name": { "family": "Marka", "given": "Z." } }, { "id": "Fry-J-L", "name": { "family": "Fry", "given": "J. L." } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "Near-UV photolysis cross sections of CH_3OOH and HOCH_2OOH determined via action spectroscopy", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 Author(s) 2006. This work is licensed under a Creative Commons License. \n\nReceived: 18 October 2006 \u2013 Accepted: 2 November 2006 \u2013 Published: 20 November 2006 \n\nThe authors thank the National Science Foundation (ATM-0432377) and the Massachusetts Institute of Technology, Air Quality Models Project (R824970-01-0) for support of this research. \n\nSRef-ID: 1680-7375/acpd/2006-6-11597\n\nPublished - ROEacpd06b.pdf
", "abstract": "Knowledge of molecular photolysis cross sections is important for determining atmospheric lifetimes and fates of many species. A method and laser apparatus for measurement of these cross sections in the near-ultraviolet (UV) region is described. The technique is based on action spectroscopy, where the yield of a photodissociation product (in this case OH) is measured as a function of excitation energy. For compounds yielding OH, this method can be used to measure near-UV photodissociation cross section as low as 10^\u221223 cm^2 molecule\u22121. The method is applied to determine the photodissociation cross sections for methyl hydroperoxide (CH3OOH; MHP) and hydroxymethyl hydroperoxide (HOCH2OOH; HMHP) in the 305\u2013365 nm wavelength range. The measured cross sections are in good agreement with previous measurements of absorption cross sections.", "date": "2006-11-20", "date_type": "published", "publication": "Atmospheric Chemistry and Physics Discussions", "volume": "6", "number": "6", "publisher": "European Geosciences Union", "pagerange": "11597-11620", "id_number": "CaltechAUTHORS:ROEacpd06b", "issn": "1680-7367", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:ROEacpd06b", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "ATM-0432377" }, { "agency": "Environmental Protection Agency (EPA)", "grant_number": "R824970-01-0" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "primary_object": { "basename": "ROEacpd06b.pdf", "url": "https://authors.library.caltech.edu/records/hpzfj-8c316/files/ROEacpd06b.pdf" }, "resource_type": "article", "pub_year": "2006", "author_list": "Roehl, C. M.; Marka, Z.; et el." }, { "id": "https://authors.library.caltech.edu/records/ghd24-b9m84", "eprint_id": 46638, "eprint_status": "archive", "datestamp": "2023-08-22 06:57:16", "lastmod": "2023-10-26 19:53:46", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Crounse-J-D", "name": { "family": "Crounse", "given": "John D." }, "orcid": "0000-0001-5443-729X" }, { "id": "McKinney-K-A", "name": { "family": "McKinney", "given": "Karena A." }, "orcid": "0000-0003-1129-1678" }, { "id": "Kwan-Alan-J", "name": { "family": "Kwan", "given": "Alan J." } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "Measurement of gas-phase hydroperoxides by chemical ionization mass spectrometry", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2006 American Chemical Society. \n\nReceived for review March 8, 2006. Accepted June 28,\n2006. \n\nWe thank Dan O'Sullivan, Julie Snow, Haiwei Shen, and Brian\nHeikes for allowing us to show their H_(2)O_(2) and PAA data prior to publication. We thank Norton Allen and James Oliver for their assistance in the preparation of the CIMS instrument for the DC-8. We thank Suresh Dhaniyala for his assistance in the design of\nthe inlet. Funding for this work was provided by a grant from the\nNational Aeronautics and Space Administration (NAG: NNG04-\nGA59G). J.D.C. and A.J.K. thank the EPA-STAR Fellowship Program (FP916334012) and the NSF Graduate Research Fellowship\nprogram, respectively, for providing support. This work has\nnot been formally reviewed by the EPA. The views expressed in\nthis document are solely those of the authors and the EPA does\nnot endorse any products or commercial services mentioned in\nthis publication.\n\nSupplemental Material - ac0604235si20060620_010148.pdf
", "abstract": "A new method for the detection of gas-phase hydroperoxides is described. The clustering chemistry of CF_(3)O^(-) is exploited to produce speciated measurements of several hydroperoxides with high sensitivity and fast time response. Correspondence of airborne observations made with this technique and the established HPLC method is illustrated. CF_(3)O^(-) appears to be a highly versatile reagent ion for measurements of both weak and strong acids in the atmosphere.", "date": "2006-10-01", "date_type": "published", "publication": "Analytical Chemistry", "volume": "78", "number": "19", "publisher": "American Chemical Society", "pagerange": "6726-6732", "id_number": "CaltechAUTHORS:20140702-114950015", "issn": "0003-2700", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140702-114950015", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NNG04-GA59G" }, { "agency": "Environmental Protection Agency (EPA)", "grant_number": "FP916334012" }, { "agency": "NSF Graduate Research Fellowship" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1021/ac0604235", "primary_object": { "basename": "ac0604235si20060620_010148.pdf", "url": "https://authors.library.caltech.edu/records/ghd24-b9m84/files/ac0604235si20060620_010148.pdf" }, "resource_type": "article", "pub_year": "2006", "author_list": "Crounse, John D.; McKinney, Karena A.; et el." }, { "id": "https://authors.library.caltech.edu/records/1m1wx-pe713", "eprint_id": 46628, "eprint_status": "archive", "datestamp": "2023-08-22 06:13:32", "lastmod": "2023-10-26 19:53:23", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Kwan-Alan-J", "name": { "family": "Kwan", "given": "Alan J." } }, { "id": "Crounse-J-D", "name": { "family": "Crounse", "given": "John D." }, "orcid": "0000-0001-5443-729X" }, { "id": "Clarke-A-D", "name": { "family": "Clarke", "given": "Antony D." } }, { "id": "Shinozuka-Yohei", "name": { "family": "Shinozuka", "given": "Yohei" } }, { "id": "Anderson-B-E", "name": { "family": "Anderson", "given": "Bruce E." } }, { "id": "Crawford-J-H", "name": { "family": "Crawford", "given": "James H." } }, { "id": "Avery-M-A", "name": { "family": "Avery", "given": "Melody A." } }, { "id": "McNaughton-C-S", "name": { "family": "McNaughton", "given": "Cameron S." } }, { "id": "Brune-W-H", "name": { "family": "Brune", "given": "William H." }, "orcid": "0000-0002-1609-4051" }, { "id": "Singh-H-B", "name": { "family": "Singh", "given": "Hanwant B." } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "On the flux of oxygenated volatile organic compounds from organic aerosol oxidation", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2006 American Geophysical Union. \n\nReceived 24 February 2006; revised 17 April 2006; accepted 12 June 2006; article first published online 9 August 2006. \n\nWe thank Jonathan Abbatt (University of Toronto) for reviewing a draft of this manuscript, Steven Howell (University of Hawai'i at Manoa) for helpful discussions, Clyde Brown (NASA Langley\nResearch Center) for preparing merged data files, and the NASA Tropospheric Chemistry Program office for support of the INTEX-NA campaign (grant NNG04FA59G). This material is based upon work supported under a National Science Foundation Graduate Research Fellowship (AJK). This\narticle was also developed under a STAR Research Assistance Agreement FP-91633401-2 awarded by the U.S. Environmental Protection Agency (JDC). It has not been formally reviewed by the EPA. The views expressed in this document are solely those of the authors and the EPA does not endorse any products or commercial services mentioned in this publication.\n\nPublished - grl21507.pdf
", "abstract": "Previous laboratory and field studies suggest that oxidation of organic aerosols can be a source of oxygenated volatile organic compounds (OVOC). Using measurements of atmospheric oxidants and aerosol size distributions performed on the NASA DC-8 during the INTEX-NA campaign, we estimate the potential magnitude of the continental summertime OVOC flux from organic aerosol oxidation by OH to be as large as \u223c70 pptv C/day in the free troposphere. Contributions from O_3, H_2O_2, photolysis, and other oxidants may increase this estimate. These processes may provide a large, diffuse source of OVOC that has not been included in current atmospheric models, and thus have a significant impact on our understanding of organic aerosol, OVOC, PAN, and HO_x chemistry. The potential importance and highly uncertain nature of our estimate highlights the need for more field and laboratory studies on organic aerosol composition and aging.", "date": "2006-08", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "33", "number": "15", "publisher": "American Geophysical Union", "pagerange": "Art. No. L15815", "id_number": "CaltechAUTHORS:20140702-094853748", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140702-094853748", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NNG04FA59G" }, { "agency": "NSF Graduate Research Fellowship" }, { "agency": "Environmental Protection Agency (EPA)", "grant_number": "FP-91633401-2" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2006GL026144", "primary_object": { "basename": "grl21507.pdf", "url": "https://authors.library.caltech.edu/records/1m1wx-pe713/files/grl21507.pdf" }, "resource_type": "article", "pub_year": "2006", "author_list": "Kwan, Alan J.; Crounse, John D.; et el." }, { "id": "https://authors.library.caltech.edu/records/nf66k-q9b02", "eprint_id": 46616, "eprint_status": "archive", "datestamp": "2023-08-22 06:04:35", "lastmod": "2023-10-26 19:52:48", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "Atmospheric chemistry: Radicals follow the Sun", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 2006 Nature Publishing Group. Published online 12 July 2006.", "abstract": "Hydroxyl free radicals are part of a complex network of atmospheric chemical reactions. But a long-term study shows that their concentration can be predicted by the intensity of ultraviolet sunlight alone.", "date": "2006-07-13", "date_type": "published", "publication": "Nature", "volume": "442", "number": "7099", "publisher": "Nature Publishing Group", "pagerange": "145-146", "id_number": "CaltechAUTHORS:20140702-073607040", "issn": "0028-0836", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140702-073607040", "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": "10.1038/442145a", "resource_type": "article", "pub_year": "2006", "author_list": "Wennberg, Paul O." }, { "id": "https://authors.library.caltech.edu/records/mnns9-8zq29", "eprint_id": 46622, "eprint_status": "archive", "datestamp": "2023-08-22 05:49:18", "lastmod": "2023-10-26 19:53:08", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Kleinb\u00f6hl-A", "name": { "family": "Kleinb\u00f6hl", "given": "Armin" } }, { "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." } }, { "id": "Weisenstein-D-K", "name": { "family": "Weisenstein", "given": "Debra K." } }, { "id": "Strekowski-R-S", "name": { "family": "Strekowski", "given": "Rafal S." } }, { "id": "Nicovich-J-M", "name": { "family": "Nicovich", "given": "J. Michael" } }, { "id": "Wine-P-H", "name": { "family": "Wine", "given": "Paul H." } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "On the stratospheric chemistry of hydrogen cyanide", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2006 American Geophysical Union. \n\nReceived 9 February 2006; revised 30 March 2006; accepted 24 April 2006; article first published online 3 June 2006. \n\nWe would like to thank the various launch crews for conducting the balloon flights, and D. Petterson and J. Landeros of JPL for their excellent support prior and during the measurement\ncampaigns. Work at AER was supported by the NASA ACMAP program. Work at Georgia Tech was supported by the NASA UARP program. Work at Jet Propulsion Laboratory, California Institute of Technology, was performed under a contract with the National Aeronautics and Space Administration.\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 - grl21441.pdf
Supplemental Material - grl21441-sup-0001-readme.txt
Supplemental Material - grl21441-sup-0002-ts01.txt
Supplemental Material - grl21441-sup-0003-fs01.eps
Supplemental Material - grl21441-sup-0004-fs02.eps
Supplemental Material - grl21441-sup-0005-t01.txt
", "abstract": "HCN profiles measured by solar occultation spectrometry during 10 balloon flights of the JPL MkIV instrument are presented. The HCN profiles reveal a compact correlation with stratospheric tracers. Calculations with a 2D-model using established rate coefficients for the reactions of HCN with OH and O(^1D) severely underestimate the measured HCN in the middle and upper stratosphere. The use of newly available rate coefficients for these reactions gives reasonable agreement of measured and modeled HCN. An HCN yield of \u223c30% from the reaction of CH_3CN with OH is consistent with the measurements.", "date": "2006-06", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "33", "number": "11", "publisher": "American Geophysical Union", "pagerange": "Art. No. L11806", "id_number": "CaltechAUTHORS:20140702-092728888", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140702-092728888", "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": "10.1029/2006GL026015", "primary_object": { "basename": "grl21441-sup-0001-readme.txt", "url": "https://authors.library.caltech.edu/records/mnns9-8zq29/files/grl21441-sup-0001-readme.txt" }, "related_objects": [ { "basename": "grl21441-sup-0002-ts01.txt", "url": "https://authors.library.caltech.edu/records/mnns9-8zq29/files/grl21441-sup-0002-ts01.txt" }, { "basename": "grl21441-sup-0003-fs01.eps", "url": "https://authors.library.caltech.edu/records/mnns9-8zq29/files/grl21441-sup-0003-fs01.eps" }, { "basename": "grl21441-sup-0004-fs02.eps", "url": "https://authors.library.caltech.edu/records/mnns9-8zq29/files/grl21441-sup-0004-fs02.eps" }, { "basename": "grl21441-sup-0005-t01.txt", "url": "https://authors.library.caltech.edu/records/mnns9-8zq29/files/grl21441-sup-0005-t01.txt" }, { "basename": "grl21441.pdf", "url": "https://authors.library.caltech.edu/records/mnns9-8zq29/files/grl21441.pdf" } ], "resource_type": "article", "pub_year": "2006", "author_list": "Kleinb\u00f6hl, Armin; Toon, Geoffrey C.; et el." }, { "id": "https://authors.library.caltech.edu/records/9ht0w-2tp16", "eprint_id": 46640, "eprint_status": "archive", "datestamp": "2023-08-22 05:44:08", "lastmod": "2023-10-26 19:53:53", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Fry-J-L", "name": { "family": "Fry", "given": "Juliane L." } }, { "id": "Matthews-J", "name": { "family": "Matthews", "given": "Jamie" } }, { "id": "Lane-J-R", "name": { "family": "Lane", "given": "Joseph R." } }, { "id": "Roehl-C-M", "name": { "family": "Roehl", "given": "Coleen M." }, "orcid": "0000-0001-5383-8462" }, { "id": "Sinha-A", "name": { "family": "Sinha", "given": "Amitabha" }, "orcid": "0000-0002-7122-3549" }, { "id": "Kjaergaard-H-G", "name": { "family": "Kjaergaard", "given": "Henrik G." }, "orcid": "0000-0002-7275-8297" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "OH-Stretch Vibrational Spectroscopy of Hydroxymethyl Hydroperoxide", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2006 American Chemical Society. \n\nReceived: February 25, 2006; In Final Form: April 12, 2006. Publication Date (Web): May 17, 2006. \n\nThe authors thank Mitchio Okumura, Daniel Schofield, Daryl Howard, and John Barker for valuable\ndiscussions. J.L.F. gratefully acknowledges funding provided\nby an American Association of University Women Dissertation\nFellowship, and J.R.L. gratefully acknowledges a Top Achiever Doctoral scholarship from the Tertiary Education Commission. Funding for this work was provided by grants to P.O.W. from the National Science Foundation Division of Atmospheric Sciences (Grant ATM-0432377), to A.S. from the National Science Foundation Division of Chemistry (Grant CHE-0211496), and to H.G.K. from the Marsden Fund administered by the Royal Society of New Zealand. P.O.W. thanks the Department of Chemistry, Otago University, for support during sabbatical leave.\n\nSupplemental Material - jp0612127si20060225_122329.txt
Supplemental Material - jp0612127si20060225_122400.txt
Supplemental Material - jp0612127si20060412_091209.pdf
", "abstract": "We report measurement and analysis of the photodissociation spectrum of hydroxymethyl hydroperoxide (HOCH_2OOH) and its partially deuterated analogue, HOCD_2OOH, in the OH-stretching region. Spectra are obtained by Fourier transform infrared spectroscopy in the 1\u03bd_(OH) and 2\u03bd_(OH) regions, and by laser induced fluorescence detection of the OH fragment produced from dissociation of HOCH_2OOH initiated by excitation of the 4\u03bd_(OH) and 5\u03bd_(OH) overtone regions (action spectroscopy). A one-dimensional local-mode model of each OH chromophore is used with ab initio calculated OH-stretching potential energy and dipole moment curves at the coupled-cluster level of theory. Major features in the observed absorption and photodissociation spectra are explained by our local-mode model. In the 4\u03bd_(OH) region, explanation of the photodissocation spectrum requires a nonuniform quantum yield, which is estimated by assuming statistical energy distribution in the excited state. Based on the estimated dissociation threshold, overtone photodissociation is not expected to significantly influence the atmospheric lifetime of hydroxymethyl hydroperoxide.", "date": "2006-05-17", "date_type": "published", "publication": "Journal of Physical Chemistry A", "volume": "110", "number": "22", "publisher": "American Chemical Society", "pagerange": "1072-7079", "id_number": "CaltechAUTHORS:20140702-132433985", "issn": "1089-5639", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140702-132433985", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "AAUW Dissertation Fellowship" }, { "agency": "Tertiary Education Commission Top Achiever Doctoral scholarship" }, { "agency": "NSF", "grant_number": "ATM-0432377" }, { "agency": "NSF", "grant_number": "CHE-0211496" }, { "agency": "Royal Society of New Zealand Marsden Fund" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1021/jp0612127", "primary_object": { "basename": "jp0612127si20060225_122400.txt", "url": "https://authors.library.caltech.edu/records/9ht0w-2tp16/files/jp0612127si20060225_122400.txt" }, "related_objects": [ { "basename": "jp0612127si20060412_091209.pdf", "url": "https://authors.library.caltech.edu/records/9ht0w-2tp16/files/jp0612127si20060412_091209.pdf" }, { "basename": "jp0612127si20060225_122329.txt", "url": "https://authors.library.caltech.edu/records/9ht0w-2tp16/files/jp0612127si20060225_122329.txt" } ], "resource_type": "article", "pub_year": "2006", "author_list": "Fry, Juliane L.; Matthews, Jamie; et el." }, { "id": "https://authors.library.caltech.edu/records/bxmng-5gd79", "eprint_id": 46620, "eprint_status": "archive", "datestamp": "2023-08-22 04:31:59", "lastmod": "2023-10-26 19:53:01", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Kleinb\u00f6hl-A", "name": { "family": "Kleinb\u00f6hl", "given": "Armin" } }, { "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." } }, { "id": "Weisenstein-D-K", "name": { "family": "Weisenstein", "given": "Debra K." } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "Infrared measurements of atmospheric CH_3CN", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2005 American Geophysical Union. \n\nReceived 2 August 2005; revised 6 September 2005; accepted 20 September 2005; article first published online 6 December 2005. \n\nWe would like to thank the various launch crews for conducting the balloon flights, and to D. Petterson and J. Landeros of JPL for their excellent support prior and during the measurement\ncampaigns. We also wish to thank S. Sharpe and C. Rinsland for providing their CH_3CN absorption cross sections prior to publication, and A. Goldman and I. Kleiner for valuable discussions about the CH_3CN partition function. Thanks also to J. Margolis, L. Brown, and again C. Rinsland for laboratory spectra from Kitt Peak. Work at AER was\nsupported by the NASA Atmospheric Chemistry Modeling and Analysis Program. Work at the Jet Propulsion Laboratory, California Institute of Technology, was performed under a contract with the National Aeronautics and Space Administration.\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 - grl20563.pdf
Supplemental Material - grl20563-sup-0001-README.txt
Supplemental Material - grl20563-sup-0002-text01.txt
Supplemental Material - grl20563-sup-0003-ts01.txt
Supplemental Material - grl20563-sup-0004-ts02.txt
Supplemental Material - grl20563-sup-0005-fs01.eps
Supplemental Material - grl20563-sup-0006-fs02.eps
Supplemental Material - grl20563-sup-0007-text02.txt
Supplemental Material - grl20563-sup-0008-ts03.txt
Supplemental Material - grl20563-sup-0009-ts04.txt
Supplemental Material - grl20563-sup-0011-text01.txt
Supplemental Material - grl20563-sup-0012-ts01.txt
Supplemental Material - grl20563-sup-0013-ts02.txt
Supplemental Material - grl20563-sup-0014-fs01.eps
Supplemental Material - grl20563-sup-0015-fs02.eps
Supplemental Material - grl20563-sup-0016-text02.txt
Supplemental Material - grl20563-sup-0017-ts03.txt
Supplemental Material - grl20563-sup-0018-ts04.txt
Supplemental Material - grl20563-sup-0019-text03.txt
Updated - grl20563-sup-0010-text03.txt
", "abstract": "For the first time CH_3CN has been measured in the Earth's atmosphere by means of infrared remote sensing. Vertical profiles of volume mixing ratio were retrieved from 12 solar occultation measurements by the balloon-borne JPL MkIV interferometer between 1993 and 2004. Profile retrieval is possible in an altitude range between 12 and 30 km with a precision of \u223c20 ppt in the Arctic and \u223c30 ppt at mid-latitudes. The retrieved CH_3CN profiles show mixing ratios of 100\u2013150 ppt a few kilometers above the tropopause that decrease to values below 40 ppt at altitudes between 22 and 30 km. The CH_3CN mixing ratios show a reasonably compact correlation with the stratospheric tracers CH_3Cl and CH_4. The CH_3CN altitude profiles and tracer correlations are well reproduced by a 2-dimensional model, suggesting that CH_3CN is long-lived in the lower stratosphere and that previously-proposed ion-molecule reactions do not play a major role as loss processes of CH_3CN.", "date": "2005-12", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "32", "number": "23", "publisher": "American Geophysical Union", "pagerange": "Art. No. L23807", "id_number": "CaltechAUTHORS:20140702-090327628", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140702-090327628", "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": "10.1029/2005GL024283", "primary_object": { "basename": "grl20563-sup-0012-ts01.txt", "url": "https://authors.library.caltech.edu/records/bxmng-5gd79/files/grl20563-sup-0012-ts01.txt" }, "related_objects": [ { "basename": "grl20563-sup-0014-fs01.eps", "url": "https://authors.library.caltech.edu/records/bxmng-5gd79/files/grl20563-sup-0014-fs01.eps" }, { "basename": "grl20563-sup-0016-text02.txt", "url": "https://authors.library.caltech.edu/records/bxmng-5gd79/files/grl20563-sup-0016-text02.txt" }, { "basename": "grl20563-sup-0002-text01.txt", "url": "https://authors.library.caltech.edu/records/bxmng-5gd79/files/grl20563-sup-0002-text01.txt" }, { "basename": "grl20563-sup-0004-ts02.txt", "url": "https://authors.library.caltech.edu/records/bxmng-5gd79/files/grl20563-sup-0004-ts02.txt" }, { "basename": "grl20563-sup-0006-fs02.eps", "url": "https://authors.library.caltech.edu/records/bxmng-5gd79/files/grl20563-sup-0006-fs02.eps" }, { "basename": "grl20563-sup-0007-text02.txt", "url": "https://authors.library.caltech.edu/records/bxmng-5gd79/files/grl20563-sup-0007-text02.txt" }, { "basename": "grl20563-sup-0011-text01.txt", "url": "https://authors.library.caltech.edu/records/bxmng-5gd79/files/grl20563-sup-0011-text01.txt" }, { "basename": "grl20563-sup-0017-ts03.txt", "url": "https://authors.library.caltech.edu/records/bxmng-5gd79/files/grl20563-sup-0017-ts03.txt" }, { "basename": "grl20563-sup-0018-ts04.txt", "url": "https://authors.library.caltech.edu/records/bxmng-5gd79/files/grl20563-sup-0018-ts04.txt" }, { "basename": "grl20563-sup-0019-text03.txt", "url": "https://authors.library.caltech.edu/records/bxmng-5gd79/files/grl20563-sup-0019-text03.txt" }, { "basename": "grl20563-sup-0005-fs01.eps", "url": "https://authors.library.caltech.edu/records/bxmng-5gd79/files/grl20563-sup-0005-fs01.eps" }, { "basename": "grl20563-sup-0001-README.txt", "url": "https://authors.library.caltech.edu/records/bxmng-5gd79/files/grl20563-sup-0001-README.txt" }, { "basename": "grl20563-sup-0010-text03.txt", "url": "https://authors.library.caltech.edu/records/bxmng-5gd79/files/grl20563-sup-0010-text03.txt" }, { "basename": "grl20563-sup-0013-ts02.txt", "url": "https://authors.library.caltech.edu/records/bxmng-5gd79/files/grl20563-sup-0013-ts02.txt" }, { "basename": "grl20563.pdf", "url": "https://authors.library.caltech.edu/records/bxmng-5gd79/files/grl20563.pdf" }, { "basename": "grl20563-sup-0003-ts01.txt", "url": "https://authors.library.caltech.edu/records/bxmng-5gd79/files/grl20563-sup-0003-ts01.txt" }, { "basename": "grl20563-sup-0008-ts03.txt", "url": "https://authors.library.caltech.edu/records/bxmng-5gd79/files/grl20563-sup-0008-ts03.txt" }, { "basename": "grl20563-sup-0009-ts04.txt", "url": "https://authors.library.caltech.edu/records/bxmng-5gd79/files/grl20563-sup-0009-ts04.txt" }, { "basename": "grl20563-sup-0015-fs02.eps", "url": "https://authors.library.caltech.edu/records/bxmng-5gd79/files/grl20563-sup-0015-fs02.eps" } ], "resource_type": "article", "pub_year": "2005", "author_list": "Kleinb\u00f6hl, Armin; Toon, Geoffrey C.; et el." }, { "id": "https://authors.library.caltech.edu/records/m803q-18418", "eprint_id": 46617, "eprint_status": "archive", "datestamp": "2023-08-22 03:21:10", "lastmod": "2023-10-26 19:52:50", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Salawitch-R-J", "name": { "family": "Salawitch", "given": "R. J." } }, { "id": "Weisenstein-D-K", "name": { "family": "Weisenstein", "given": "D. K." } }, { "id": "Kovalenko-L-J", "name": { "family": "Kovalenko", "given": "L. J." } }, { "id": "Sioris-C-E", "name": { "family": "Sioris", "given": "C. E." } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Chance-K", "name": { "family": "Chance", "given": "K." } }, { "id": "Ko-M-K-W", "name": { "family": "Ko", "given": "M. K. W." } }, { "id": "McLinden-C-A", "name": { "family": "McLinden", "given": "C. A." } } ] }, "title": "Sensitivity of ozone to bromine in the lower stratosphere", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2005 American Geophysical Union. \n\nReceived 15 September 2004; revised 23 November 2004; accepted 3 February 2005; article first published online 9 March 2005. \n\nWe thank R. Schofield for helpful discussions and sharing results prior to publication, W. Randel for sharing O_3 trend data files, F. Goutail for providing SAOZ BrO data files, and the\nreviewers for constructive comments. Research at the Jet Propulsion Laboratory, California Institute of Technology, is performed under contract with the National Aeronautics and Space Administration (NASA). Research at the Smithsonian Astrophysical Observatory is supported by NASA and the Smithsonian Institution. Work at AER is funded by the NASA ACMAP and SOSST programs.\n\nPublished - grl19102.pdf
Supplemental Material - grl19102-sup-0001-README.txt
Supplemental Material - grl19102-sup-0002-text.txt
Supplemental Material - grl19102-sup-0003-supp.pdf
Supplemental Material - grl19102-sup-0004-fig6.eps
Supplemental Material - grl19102-sup-0005-fig7.eps
Supplemental Material - grl19102-sup-0006-fig8.eps
Supplemental Material - grl19102-sup-0007-fig9.eps
Supplemental Material - grl19102-sup-0008-tbl1.txt
Supplemental Material - grl19102-sup-0009-tbl2.txt
Supplemental Material - grl19102-sup-0010-tbl3.txt
", "abstract": "Measurements of BrO suggest that inorganic bromine (Br_y) at and above the tropopause is 4 to 8 ppt greater than assumed in models used in past ozone trend assessment studies. This additional bromine is likely carried to the stratosphere by short-lived biogenic compounds and their decomposition products, including tropospheric BrO. Including this additional bromine in an ozone trend simulation increases the computed ozone depletion over the past \u223c25 years, leading to better agreement between measured and modeled ozone trends. This additional Br_y (assumed constant over time) causes more ozone depletion because associated BrO provides a reaction partner for ClO, which increases due to anthropogenic sources. Enhanced Br_y causes photochemical loss of ozone below \u223c14 km to change from being controlled by HO_x catalytic cycles (primarily HO_2+O_3) to a situation where loss by the BrO+HO_2 cycle is also important.", "date": "2005-03-09", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "32", "number": "5", "publisher": "American Geophysical Union", "pagerange": "Art. No. L05811", "id_number": "CaltechAUTHORS:20140702-074734843", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140702-074734843", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA" }, { "agency": "Smithsonian Institution" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2004GL021504", "primary_object": { "basename": "grl19102-sup-0009-tbl2.txt", "url": "https://authors.library.caltech.edu/records/m803q-18418/files/grl19102-sup-0009-tbl2.txt" }, "related_objects": [ { "basename": "grl19102-sup-0007-fig9.eps", "url": "https://authors.library.caltech.edu/records/m803q-18418/files/grl19102-sup-0007-fig9.eps" }, { "basename": "grl19102-sup-0002-text.txt", "url": "https://authors.library.caltech.edu/records/m803q-18418/files/grl19102-sup-0002-text.txt" }, { "basename": "grl19102-sup-0003-supp.pdf", "url": "https://authors.library.caltech.edu/records/m803q-18418/files/grl19102-sup-0003-supp.pdf" }, { "basename": "grl19102-sup-0004-fig6.eps", "url": "https://authors.library.caltech.edu/records/m803q-18418/files/grl19102-sup-0004-fig6.eps" }, { "basename": "grl19102-sup-0005-fig7.eps", "url": "https://authors.library.caltech.edu/records/m803q-18418/files/grl19102-sup-0005-fig7.eps" }, { "basename": "grl19102-sup-0006-fig8.eps", "url": "https://authors.library.caltech.edu/records/m803q-18418/files/grl19102-sup-0006-fig8.eps" }, { "basename": "grl19102-sup-0008-tbl1.txt", "url": "https://authors.library.caltech.edu/records/m803q-18418/files/grl19102-sup-0008-tbl1.txt" }, { "basename": "grl19102-sup-0010-tbl3.txt", "url": "https://authors.library.caltech.edu/records/m803q-18418/files/grl19102-sup-0010-tbl3.txt" }, { "basename": "grl19102-sup-0001-README.txt", "url": "https://authors.library.caltech.edu/records/m803q-18418/files/grl19102-sup-0001-README.txt" }, { "basename": "grl19102.pdf", "url": "https://authors.library.caltech.edu/records/m803q-18418/files/grl19102.pdf" } ], "resource_type": "article", "pub_year": "2005", "author_list": "Salawitch, R. J.; Weisenstein, D. K.; et el." }, { "id": "https://authors.library.caltech.edu/records/94tk1-cha44", "eprint_id": 299, "eprint_status": "archive", "datestamp": "2023-08-22 03:11:44", "lastmod": "2023-10-13 20:36:45", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Nizkorodov-S-A", "name": { "family": "Nizkorodov", "given": "S. A." } }, { "id": "Crounse-J-D", "name": { "family": "Crounse", "given": "J. D." }, "orcid": "0000-0001-5443-729X" }, { "id": "Fry-J-L", "name": { "family": "Fry", "given": "J. L." } }, { "id": "Roehl-C-M", "name": { "family": "Roehl", "given": "C. M." }, "orcid": "0000-0001-5383-8462" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "Near-IR photodissociation of peroxy acetyl nitrate", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2005 Author(s). This work is licensed under a Creative Commons License. \n\nReceived: 4 February 2004 \u2013 Published in Atmos. Chem. Phys. Discuss.: 1 March 2004; Revised: 28 April 2004 \u2013 Accepted: 7 May 2004 \u2013 Published: 10 February 2005. \n\nThis work was funded in part by NASA's Atmospheric Effects of Aviation Program and the Atmospheric Chemistry program of the National Science Foundation. SAN thanks the Camille and Henry Dreyfus Foundation for financial support during his postdoctoral research at Caltech. The authors thank R. Salawitch (JPL) for providing 24-averaged UV-photolysis rates of PAN used in Fig. 5 and A. Sinha (UCSD) for a preprint of Ref. (Matthews et al., 2004).\n\nPublished - NIZacp05.pdf
", "abstract": "Measurements of the C-H overtone transition strengths combined with estimates of the photodissociation cross sections for these transitions suggest that near-IR photodissociation of peroxy acetyl nitrate (PAN) is less significant (Jnear\u2212IR ~3\u00d710^\u22128 s^\u22121 at noon) in the lower atmosphere than competing sinks resulting from unimolecular decomposition and ultraviolet photolysis. This is in contrast to the photochemical behavior of a related peroxy nitrate, pernitric acid (PNA), that undergoes rapid near-IR photolysis in the atmosphere with Jnear\u2212IR ~10^\u22125 s^\u22121 at noon (Roehl et al., 2002). This difference is attributed to the larger binding energy and larger number of vibrational degrees of 10 freedom in PAN, which make 4[Greek nu]CH the lowest overtone excitation with a high photodissociation yield (as opposed to 2[Greek nu]OH in PNA).", "date": "2005-02-10", "date_type": "published", "publication": "Atmospheric Chemistry and Physics", "volume": "5", "number": "2", "publisher": "European Geosciences Union", "pagerange": "385-392", "id_number": "CaltechAUTHORS:NIZacp05", "issn": "1680-7316", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:NIZacp05", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA" }, { "agency": "Camille and Henry Dreyfus Foundation" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "primary_object": { "basename": "NIZacp05.pdf", "url": "https://authors.library.caltech.edu/records/94tk1-cha44/files/NIZacp05.pdf" }, "resource_type": "article", "pub_year": "2005", "author_list": "Nizkorodov, S. A.; Crounse, J. D.; et el." }, { "id": "https://authors.library.caltech.edu/records/e9ywj-nfg83", "eprint_id": 46805, "eprint_status": "archive", "datestamp": "2023-08-22 03:10:20", "lastmod": "2023-10-26 19:54:40", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Yang-Z", "name": { "family": "Yang", "given": "Z." } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Cagaeo-R-P", "name": { "family": "Cageao", "given": "R. P." } }, { "id": "Pongetti-T-J", "name": { "family": "Pongetti", "given": "T. J." }, "orcid": "0000-0001-9465-0853" }, { "id": "Toon-G-C", "name": { "family": "Toon", "given": "G. C." }, "orcid": "0000-0003-4174-7541" }, { "id": "Sander-S-P", "name": { "family": "Sander", "given": "S. P." }, "orcid": "0000-0003-1424-3620" } ] }, "title": "Ground-based photon path measurements from solar absorption spectra of the O_2 A-band", "ispublished": "pub", "full_text_status": "restricted", "keywords": "O2 A-band; Photon path; Solar absorption spectra", "note": "\u00a9 2004 Elsevier Ltd. \n\nReceived 6 October 2003; accepted 13 March 2004. \n\nWe thank Linda Brown, Camy-Peyret and David Crisp for many helpful discussions, Rebecca Washenfelder for providing comparison spectra. Part of this work was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under contract with NASA. Paul Wennberg, Geoff Toon, and Zhonghua Yang acknowledge support from NASA's ACMAP and Terrestrial Ecology Programs (NAG5-11739; NAG12247). Stan Sander, Rich Cageao, and Tom Pongetti acknowledge support from the NASA's Upper Atmosphere Research Program.", "abstract": "High-resolution solar absorption spectra obtained from Table Mountain Facility (TMF, 34.38\u00b0N, 117.68\u00b0W, 2286 m elevation) have been analyzed in the region of the O_2 A-band. The photon paths of direct sunlight in clear sky cases are retrieved from the O_2 absorption lines and compared with ray-tracing calculations based on the solar zenith angle and surface pressure. At a given zenith angle, the ratios of retrieved to geometrically derived photon paths are highly precise (\u223c0.2%), but they vary as the zenith angle changes. This is because current models of the spectral lineshape in this band do not properly account for the significant absorption that exists far from the centers of saturated lines. For example, use of a Voigt function with Lorentzian far wings results in an error in the retrieved photon path of as much as 5%, highly correlated with solar zenith angle. Adopting a super-Lorentz function reduces, but does not completely eliminate this problem. New lab measurements of the lineshape are required to make further progress.", "date": "2005-02-01", "date_type": "published", "publication": "Journal of Quantitative Spectroscopy and Radiative Transfer", "volume": "90", "number": "3-4", "publisher": "Elsevier", "pagerange": "309-321", "id_number": "CaltechAUTHORS:20140703-101456060", "issn": "0022-4073", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140703-101456060", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NAG5-11739" }, { "agency": "NASA", "grant_number": "NAG12247" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/j.jqsrt.2004.03.020", "resource_type": "article", "pub_year": "2005", "author_list": "Yang, Z.; Wennberg, P. O.; et el." }, { "id": "https://authors.library.caltech.edu/records/v31f2-yqr89", "eprint_id": 59705, "eprint_status": "archive", "datestamp": "2023-08-22 02:38:35", "lastmod": "2023-10-23 22:37:51", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Dhaniyala-S", "name": { "family": "Dhaniyala", "given": "S." } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Flagan-R-C", "name": { "family": "Flagan", "given": "R. C." }, "orcid": "0000-0001-5690-770X" }, { "id": "Fahey-D-W", "name": { "family": "Fahey", "given": "D. W." } }, { "id": "Northway-M-J", "name": { "family": "Northway", "given": "M. J." } }, { "id": "Gao-R-S", "name": { "family": "Gao", "given": "R. S." } }, { "id": "Bui-T-P", "name": { "family": "Bui", "given": "T. P." } } ] }, "title": "Stratospheric Aerosol Sampling: Effect of a Blunt-Body Housing on Inlet Sampling Characteristics", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 2004 American Association for Aerosol Research. \n\nReceived 18 February 2004; accepted 2 September 2004. \n\nThe authors would like to thank NASA Dryden for providing the photographs of the ER-2 and the NOy instrument shown in Figure 1. We would like to thank the SOLVE team for the technical and logistical help during the campaign. P. O. Wennberg thanks NASA's UARP for funding support.", "abstract": "During a campaign to study ozone loss mechanisms in the Arctic stratosphere (SOLVE), several instruments on NASA's ER-2 aircraft observed a very low number density (0.1 I^(\u22121)) of large, nitric-acid-containing particles that form the polar stratospheric clouds (PSCs). For effective physical and chemical characterization of these particles, the measurements from these instruments have to be intercompared and integrated. In particular, proper interpretation requires knowledge of the sampling characteristics of the particles into the instruments. Here, we present the calculation of the sampling characteristics of the one of the instruments on the ER-2, the NOAA NOy instrument. This instrument sampled ambient particles and gas from two forward-facing inlets located fore and aft on a particle-separation housing (the football) and measured total NOy in the sample. In recent studies, ambient aerosol mass has been estimated by the difference of the measurements of the two inlets with the assumption that the rear inlet observations represent the gas-phase NOy and small particles and the front inlet samples represent gas-phase NOy and all particle sizes with varied efficiency (anisokinetic sampling). This knowledge was derived largely from semiempirical relations and potential flow studies of the housing. In our study, we used CFD simulations to model the compressible flow conditions and considered noncontinuum effects in calculating particle trajectories. Our simulations show that the blunt body housing the inlets has a strong and complex interaction with the flow and particles sampled by the two inlets. The simulations show that the front inlet characteristics are influenced by the effect of the blunt body on the upstream pressure field. The rear inlet sampling characteristics are influenced both by the shape and size of the inlet and its location on the blunt body. These interactions result in calculated inlet characteristics that are significantly different from previously assumed values. Analysis of the SOLVE data, considering the ambient conditions and the calculated inlet sampling characteristics, in conjunction with thermodynamic growth modeling of super-cooled ternary solution (STS) particles, provides validation of the CFD results.", "date": "2004-11", "date_type": "published", "publication": "Aerosol Science and Technology", "volume": "38", "number": "11", "publisher": "American Association for Aerosol Research", "pagerange": "1080-1090", "id_number": "CaltechAUTHORS:20150818-102244516", "issn": "0278-6826", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150818-102244516", "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": "10.1080/027868290885818", "resource_type": "article", "pub_year": "2004", "author_list": "Dhaniyala, S.; Wennberg, P. O.; et el." }, { "id": "https://authors.library.caltech.edu/records/h9xk9-4hv53", "eprint_id": 46590, "eprint_status": "archive", "datestamp": "2023-08-22 02:19:02", "lastmod": "2023-10-26 19:51:36", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Peacock-S", "name": { "family": "Peacock", "given": "Synte" }, "orcid": "0000-0002-1046-025X" }, { "id": "Randerson-J-T", "name": { "family": "Randerson", "given": "James T." }, "orcid": "0000-0001-6559-7387" }, { "id": "Bleck-R", "name": { "family": "Bleck", "given": "Rainer" } } ] }, "title": "Recent changes in the air-sea gas exchange of methyl chloroform", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2004 American Geophysical Union. \n\nReceived 7 May 2004; revised 14 June 2004; accepted 16 July 2004; article first published online 24 August 2004.\n\nPublished - grl18594.pdf
Supplemental Material - grl18594-sup-0001-README.txt
Supplemental Material - grl18594-sup-0002-SText.txt
Supplemental Material - grl18594-sup-0003-Sfigure1.eps
Supplemental Material - grl18594-sup-0004-Sfigure2.eps
Supplemental Material - grl18594-sup-0005-Sfigure3.eps
Supplemental Material - grl18594-sup-0006-Sfigure4.eps
Supplemental Material - grl18594-sup-0007-Sfigure5.eps
Supplemental Material - grl18594-sup-0008-STable1.txt
Supplemental Material - grl18594-sup-0009-STable2.txt
", "abstract": "Atmospheric measurements of methyl chloroform provide important constraints on the rate of oxidation of hydrocarbons in Earth's atmosphere. Estimates of the loss of methyl chloroform to the oceans play a small but important role in these calculations. Here, we examine the ocean-atmosphere interaction of methyl chloroform in a global ocean model. Contrary to previous assumptions, these simulations suggest that the high-latitude oceans are currently a source of this chemical to the atmosphere. If confirmed, this finding alters estimates of the change in the atmospheric oxidation rate of hydrocarbons. We highlight the potential usefulness of methyl chloroform as a tracer of ocean circulation.", "date": "2004-08-24", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "31", "number": "16", "publisher": "American Geophysical Union", "pagerange": "Art. No. L16112", "id_number": "CaltechAUTHORS:20140701-091835991", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140701-091835991", "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": "10.1029/2004GL020476", "primary_object": { "basename": "grl18594-sup-0001-README.txt", "url": "https://authors.library.caltech.edu/records/h9xk9-4hv53/files/grl18594-sup-0001-README.txt" }, "related_objects": [ { "basename": "grl18594-sup-0002-SText.txt", "url": "https://authors.library.caltech.edu/records/h9xk9-4hv53/files/grl18594-sup-0002-SText.txt" }, { "basename": "grl18594-sup-0003-Sfigure1.eps", "url": "https://authors.library.caltech.edu/records/h9xk9-4hv53/files/grl18594-sup-0003-Sfigure1.eps" }, { "basename": "grl18594-sup-0005-Sfigure3.eps", "url": "https://authors.library.caltech.edu/records/h9xk9-4hv53/files/grl18594-sup-0005-Sfigure3.eps" }, { "basename": "grl18594-sup-0004-Sfigure2.eps", "url": "https://authors.library.caltech.edu/records/h9xk9-4hv53/files/grl18594-sup-0004-Sfigure2.eps" }, { "basename": "grl18594-sup-0006-Sfigure4.eps", "url": "https://authors.library.caltech.edu/records/h9xk9-4hv53/files/grl18594-sup-0006-Sfigure4.eps" }, { "basename": "grl18594-sup-0007-Sfigure5.eps", "url": "https://authors.library.caltech.edu/records/h9xk9-4hv53/files/grl18594-sup-0007-Sfigure5.eps" }, { "basename": "grl18594-sup-0008-STable1.txt", "url": "https://authors.library.caltech.edu/records/h9xk9-4hv53/files/grl18594-sup-0008-STable1.txt" }, { "basename": "grl18594-sup-0009-STable2.txt", "url": "https://authors.library.caltech.edu/records/h9xk9-4hv53/files/grl18594-sup-0009-STable2.txt" }, { "basename": "grl18594.pdf", "url": "https://authors.library.caltech.edu/records/h9xk9-4hv53/files/grl18594.pdf" } ], "resource_type": "article", "pub_year": "2004", "author_list": "Wennberg, Paul O.; Peacock, Synte; et el." }, { "id": "https://authors.library.caltech.edu/records/y7x43-xch93", "eprint_id": 2539, "eprint_status": "archive", "datestamp": "2023-08-22 02:10:34", "lastmod": "2023-10-13 23:35:33", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Fry-J-L", "name": { "family": "Fry", "given": "Juliane L." } }, { "id": "Nizkorodov-S-A", "name": { "family": "Nizkorodov", "given": "Sergey A." } }, { "id": "Okumura-M", "name": { "family": "Okumura", "given": "Mitchio" }, "orcid": "0000-0001-6874-1137" }, { "id": "Roehl-C-M", "name": { "family": "Roehl", "given": "Coleen M." }, "orcid": "0000-0001-5383-8462" }, { "id": "Francisco-J-S", "name": { "family": "Francisco", "given": "Joseph S." } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "Cis-cis and trans-perp HOONO: Action spectroscopy and isomerization kinetics", "ispublished": "pub", "full_text_status": "public", "keywords": "isomerisation; ab initio calculations; vibrational states; molecular configurations; density functional theory; photodissociation; configuration interactions; oscillator strengths; spectral line intensity; molecular moments; coupled cluster calculations; predissociation; molecule-molecule reactions; photoexcitation; spectral line breadth; atmospheric chemistry; oxygen compounds; reaction kinetics", "note": "\u00a9 2004 American Institute of Physics.\n\n(Received 26 January 2004; accepted 21 April 2004) \n\nThis material is based upon work supported under a National Science Foundation Graduate Research Fellowship (J.L.F.) and supported by NSF's Atmospheric Chemistry program (Contract No. ATM-0094670) and the NASA Upper Atmospheric Research Program (Contract No. NAG5-11657). S.A.N. thanks the Camille and Henry Dreyfus Postdoctoral Program in Environmental Chemistry for support. The authors thank J. R. Barker for providing MULTIWELL input files and H. G. Kjaergaard, I. M. Konen, I. B. Pollack, E. X. J. Li, and M. I. Lester for insightful discussions.\n\nPublished - FRYjcp04.pdf
", "abstract": "The weakly bound HOONO product of the OH + NO_2 + M reaction is studied using the vibrational predissociation that follows excitation of the first OH overtone (2nu1). We observe formation of both cis-cis and trans-perp conformers of HOONO. The trans-perp HOONO 2nu1 band is observed under thermal (223\u2013238 K) conditions at 6971 cm^(\u20131). We assign the previously published (warmer temperature) HOONO spectrum to the 2nu1 band at 6365 cm^(\u20131) and 2nu1-containing combination bands of the cis-cis conformer of HOONO. The band shape of the trans-perp HOONO spectrum is in excellent agreement with the predicted rotational contour based on previous experimental and theoretical results, but the apparent origin of the cis-cis HOONO spectrum at 6365 cm^(\u20131) is featureless and significantly broader, suggesting more rapid intramolecular vibrational redistribution or predissociation in the latter isomer. The thermally less stable trans-perp HOONO isomerizes rapidly to cis-cis HOONO with an experimentally determined lifetime of 39 ms at 233 K at 13 hPa (in a buffer gas of predominantly Ar). The temperature dependence of the trans-perp HOONO lifetime in the range 223\u2013238 K yields an isomerization barrier of 33\u00b112 kJ/mol. New ab initio calculations of the structure and vibrational mode frequencies of the transition state perp-perp HOONO are performed using the coupled cluster singles and doubles with perturbative triples [CCSD(T)] model, using a correlation consistent polarized triple zeta basis set (cc-pVTZ). The energetics of cis-cis, trans-perp, and perp-perp HOONO are also calculated at this level [CCSD(T)/cc-pVTZ] and with a quadruple zeta basis set using the structure determined at the triple zeta basis set [CCSD(T)/cc-pVQZ//CCSD(T)/cc-pVTZ]. These calculations predict that the anti form of perp-perp HOONO has an energy of DeltaE0 = 42.4 kJ/mol above trans-perp HOONO, corresponding to an activation enthalpy of DeltaH298[double-dagger]0 = 41.1 kJ/mol. These results are in good agreement with statistical simulations based on a model developed by Golden, Barker, and Lohr. The simulated isomerization rates match the observed decay rates when modeled with a trans-perp to cis-cis HOONO isomerization barrier of 40.8 kJ/mol and a strong collision model. The quantum yield of cis-cis HOONO dissociation to OH and NO2 is also calculated as a function of photon excitation energy in the range 3500\u20137500 cm^(\u20131), assuming D0 = 83 kJ/mol. The quantum yield is predicted to vary from 0.15 to 1 over the observed spectrum at 298 K, leading to band intensities in the action spectrum that are highly temperature dependent; however, the observed relative band strengths in the cis-cis HOONO spectrum do not change substantially with temperature over the range 193\u2013273 K. Semiempirical calculations of the oscillator strengths for 2nu1(cis-cis HOONO) and 2nu1(trans-perp HOONO) are performed using (1) a one-dimensional anharmonic model and (2) a Morse oscillator model for the OH stretch, and ab initio dipole moment functions calculated using Becke, Lee, Yang, and Parr density functional theory (B3LYP), M\u00f8ller-Plesset pertubation theory truncated at the second and third order (MP2 and MP3), and quadratic configuration interaction theory using single and double excitations (QCISD). The QCISD level calculated ratio of 2nu1 oscillator strengths of trans-perp to cis-cis HOONO is 3.7:1. The observed intensities indicate that the concentration of trans-perp HOONO early in the OH + NO2 reaction is significantly greater than predicted by a Boltzmann distribution, consistent with statistical predictions of high initial yields of trans-perp HOONO from the OH + NO_2 + M reaction. In the atmosphere, trans-perp HOONO will isomerize nearly instantaneously to cis-cis HOONO. Loss of HOONO via photodissociation in the near-IR limits the lifetime of cis-cis HOONO during daylight to less than 45 h, other loss mechanisms will reduce the lifetime further.", "date": "2004-07-15", "date_type": "published", "publication": "Journal of Chemical Physics", "volume": "121", "number": "3", "publisher": "American Institute of Physics", "pagerange": "1432-1448", "id_number": "CaltechAUTHORS:FRYjcp04", "issn": "0021-9606", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:FRYjcp04", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF Graduate Research Fellowship" }, { "agency": "NSF", "grant_number": "ATM-0094670" }, { "agency": "NASA", "grant_number": "NAG5-11657" }, { "agency": "Camille and Henry Dreyfus Foundation" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1063/1.1760714", "primary_object": { "basename": "FRYjcp04.pdf", "url": "https://authors.library.caltech.edu/records/y7x43-xch93/files/FRYjcp04.pdf" }, "resource_type": "article", "pub_year": "2004", "author_list": "Fry, Juliane L.; Nizkorodov, Sergey A.; et el." }, { "id": "https://authors.library.caltech.edu/records/tyxn8-nn168", "eprint_id": 46588, "eprint_status": "archive", "datestamp": "2023-08-22 01:43:03", "lastmod": "2023-10-26 19:51:29", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "McKinney-K-A", "name": { "family": "McKinney", "given": "K. A." }, "orcid": "0000-0003-1129-1678" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Dhaniyala-S", "name": { "family": "Dhaniyala", "given": "S." } }, { "id": "Fahey-D-W", "name": { "family": "Fahey", "given": "D. W." } }, { "id": "Northway-M-J", "name": { "family": "Northway", "given": "M. J." } }, { "id": "K\u00fcnzi-K-F", "name": { "family": "K\u00fcnzi", "given": "K. F." } }, { "id": "Kleinb\u00f6hl-A", "name": { "family": "Kleinb\u00f6hl", "given": "A." } }, { "id": "Sinnhuber-M", "name": { "family": "Sinnhuber", "given": "M." } }, { "id": "K\u00fcllmann-H", "name": { "family": "K\u00fcllmann", "given": "H." } }, { "id": "Bremer-H", "name": { "family": "Bremer", "given": "H." } }, { "id": "Mahoney-M-J", "name": { "family": "Mahoney", "given": "M. J." } }, { "id": "Bui-T-P", "name": { "family": "Bui", "given": "T. P." } } ] }, "title": "Trajectory studies of large HNO_3-containing PSC particles in the Arctic: Evidence for the role of NAT", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2004 American Geophysical Union. \n\nReceived 15 August 2003; revised 9 January 2004; accepted 23 January 2004; article first published online 6 March 2004. \n\nThanks to Drs. L. Lait, M. Schoeberl, and P. A. Newman of the Atmospheric Chemistry and Dynamics branch at NASA GSFC for use of the Goddard Automailer. This work was supported by NSF Grant No. ATM9871353 and NASA Grant No. NAG5-8922. Work at JPL, California Institute of Technology, was carried out under contract with NASA.\n\nPublished - grl17521.pdf
Supplemental Material - grl17521-sup-0001-README.txt
Supplemental Material - grl17521-sup-0002-F04.gif
", "abstract": "Large (5 to >20 \u03bcm diameter) nitric-acid-containing polar stratospheric cloud (PSC) particles were observed in the Arctic stratosphere during the winter of 1999\u20132000. We use a particle growth and sedimentation model to investigate the environment in which these particles grew and the likely phase of the largest particles. Particle trajectory calculations show that, while simulated nitric acid dihydrate (NAD) particle sizes are significantly smaller than the observed maximum particle sizes, nitric acid trihydrate (NAT) particle trajectories are consistent with the largest observed particle sizes.", "date": "2004-03-16", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "31", "number": "5", "publisher": "American Geophysical Union", "pagerange": "Art. No. L05110", "id_number": "CaltechAUTHORS:20140701-084347634", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140701-084347634", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "ATM9871353" }, { "agency": "NASA", "grant_number": "NAG5-8922" }, { "agency": "NASA/JPL/Caltech" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2003GL018430", "primary_object": { "basename": "grl17521-sup-0001-README.txt", "url": "https://authors.library.caltech.edu/records/tyxn8-nn168/files/grl17521-sup-0001-README.txt" }, "related_objects": [ { "basename": "grl17521-sup-0002-F04.gif", "url": "https://authors.library.caltech.edu/records/tyxn8-nn168/files/grl17521-sup-0002-F04.gif" }, { "basename": "grl17521.pdf", "url": "https://authors.library.caltech.edu/records/tyxn8-nn168/files/grl17521.pdf" } ], "resource_type": "article", "pub_year": "2004", "author_list": "McKinney, K. A.; Wennberg, P. O.; et el." }, { "id": "https://authors.library.caltech.edu/records/dhbay-2hh89", "eprint_id": 297, "eprint_status": "archive", "datestamp": "2023-08-22 01:40:19", "lastmod": "2023-10-23 16:10:47", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Nizkorodov-S-A", "name": { "family": "Nizkorodov", "given": "S. A." } }, { "id": "Crounse-J-D", "name": { "family": "Crounse", "given": "J. D." }, "orcid": "0000-0001-5443-729X" }, { "id": "Fry-J-L", "name": { "family": "Fry", "given": "J. L." } }, { "id": "Roehl-C-M", "name": { "family": "Roehl", "given": "C. M." }, "orcid": "0000-0001-5383-8462" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "Near-IR photodissociation of peroxy acetyl nitrate", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 Author(s) 2004. This work is licensed under the \nCreative Commons Attribution-NonCommercial-ShareAlike 2.5 License.\n\nReceived: 4 February 2004 \u2013 Accepted: 22 February 2004 \u2013 Published: 1 March 2004. \n\nThis work was funded in part by NASA's Atmospheric Effects of Aviation Program and the Atmospheric Chemistry program of the National Science Foundation. SAN thanks the Camille and Henry Dreyfus Foundation for financial support during his postdoctoral research at Caltech. The authors thank R. Salawitch (JPL) for providing 24-averaged UV-photolysis rates of PAN used in Fig. 5 and A. Sinha (UCSD) for a preprint of Ref. (Matthews et al., 2004).\n\nPublished - NIZacpd04.pdf
", "abstract": "Measurements of the C-H overtone transition strengths combined with estimates of the photodissociation cross sections for these transitions suggest that near-IR photodissociation of peroxy acetyl nitrate (PAN) is less significant (Jnear\u2212IR ~3\u00d710^\u22128 s^\u22121 at noon) in the lower atmosphere than competing sinks resulting from unimolecular decomposition and ultraviolet photolysis. This is in contrast to the photochemical behavior of a related peroxy nitrate, pernitric acid (PNA), that undergoes rapid near-IR photolysis in the atmosphere with Jnear\u2212IR ~10^\u22125 s^\u22121 at noon (Roehl et al., 2002). This difference is attributed to the larger binding energy and larger number of vibrational degrees of 10 freedom in PAN, which make 4[Greek nu]CH the lowest overtone excitation with a high photodissociation yield (as opposed to 2[Greek nu]OH in PNA).", "date": "2004-03-01", "date_type": "published", "publication": "Atmospheric Chemistry and Physics Discussions", "volume": "4", "number": "2", "publisher": "European Geosciences Union", "pagerange": "1269-1289", "id_number": "CaltechAUTHORS:NIZacpd04", "issn": "1680-7367", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:NIZacpd04", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA" }, { "agency": "NSF" }, { "agency": "Camille and Henry Dreyfus Foundation" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.5194/acpd-4-1269-2004", "primary_object": { "basename": "NIZacpd04.pdf", "url": "https://authors.library.caltech.edu/records/dhbay-2hh89/files/NIZacpd04.pdf" }, "resource_type": "article", "pub_year": "2004", "author_list": "Nizkorodov, S. A.; Crounse, J. D.; et el." }, { "id": "https://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.edu/records/a06xk-yb678", "eprint_id": 46587, "eprint_status": "archive", "datestamp": "2023-08-22 01:14:51", "lastmod": "2023-10-26 19:51:27", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "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": "Toon-G-C", "name": { "family": "Toon", "given": "G. C." }, "orcid": "0000-0003-4174-7541" } ] }, "title": "Tropospheric methane retrieved from ground-based near-IR solar\n absorption spectra", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2003 American Geophysical Union. \n\nReceived 14 June 2003; revised 2 October 2003; accepted 29 October 2003; article first published online 13 December 2003. \n\nWe thank the Kitt Peak personnel who acquired these spectra. We thank Linda Brown, Ming Luo, James Randerson, and Zhonghua Yang for helpful discussions. We acknowledge the NOAA CMDL and GAGE/AGAGE networks for the use of their data. R.A.W. acknowledges support from NSF and the California Institute of Technology. P.O.W. and G.C.T. acknowledge support from NASA. Research at JPL, California Institute of Technology, is performed under contract with NASA.\n\nPublished - grl17293.pdf
Supplemental Material - grl17293-sup-0001-README.txt
Supplemental Material - grl17293-sup-0002-TableS1_1.txt
Supplemental Material - grl17293-sup-0003-TableS1_2.txt
Supplemental Material - grl17293-sup-0004-TableS3_1.txt
Supplemental Material - grl17293-sup-0005-FigureS2_1.eps
Supplemental Material - grl17293-sup-0006-FigureS3_1.eps
Supplemental Material - grl17293-sup-0007-FigureS3_2.eps
", "abstract": "High-resolution near-infrared solar absorption spectra recorded between 1977 and 1995 at the Kitt Peak National Solar Observatory are analyzed to retrieve column abundances of methane (CH_4), hydrogen fluoride (HF), and oxygen (O_2). Employing a stratospheric \"slope equilibrium\" relationship between CH_4 and HF, the varying contribution of stratospheric CH_4 to the total column is inferred. Variations in the CH_4 column due to changes in surface pressure are determined from the O_2 column abundances. By this technique, CH_4 tropospheric volume mixing ratios are determined with a precision of \u223c0.5%. These display behavior similar to Mauna Loa in situ surface measurements, with a seasonal peak-to-peak amplitude of approximately 30 ppbv and a nearly linear increase between 1977 and 1983 of 18.0 \u00b1 0.8 ppbv yr^(\u22121), slowing significantly after 1990.", "date": "2003-12-13", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "30", "number": "23", "publisher": "American Geophysical Union", "pagerange": "Art. No. 2226", "id_number": "CaltechAUTHORS:20140701-074803639", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140701-074803639", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF" }, { "agency": "Caltech" }, { "agency": "NASA/JPL/Caltech" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2003GL017969", "primary_object": { "basename": "grl17293-sup-0004-TableS3_1.txt", "url": "https://authors.library.caltech.edu/records/a06xk-yb678/files/grl17293-sup-0004-TableS3_1.txt" }, "related_objects": [ { "basename": "grl17293-sup-0005-FigureS2_1.eps", "url": "https://authors.library.caltech.edu/records/a06xk-yb678/files/grl17293-sup-0005-FigureS2_1.eps" }, { "basename": "grl17293-sup-0006-FigureS3_1.eps", "url": "https://authors.library.caltech.edu/records/a06xk-yb678/files/grl17293-sup-0006-FigureS3_1.eps" }, { "basename": "grl17293-sup-0007-FigureS3_2.eps", "url": "https://authors.library.caltech.edu/records/a06xk-yb678/files/grl17293-sup-0007-FigureS3_2.eps" }, { "basename": "grl17293.pdf", "url": "https://authors.library.caltech.edu/records/a06xk-yb678/files/grl17293.pdf" }, { "basename": "grl17293-sup-0001-README.txt", "url": "https://authors.library.caltech.edu/records/a06xk-yb678/files/grl17293-sup-0001-README.txt" }, { "basename": "grl17293-sup-0002-TableS1_1.txt", "url": "https://authors.library.caltech.edu/records/a06xk-yb678/files/grl17293-sup-0002-TableS1_1.txt" }, { "basename": "grl17293-sup-0003-TableS1_2.txt", "url": "https://authors.library.caltech.edu/records/a06xk-yb678/files/grl17293-sup-0003-TableS1_2.txt" } ], "resource_type": "article", "pub_year": "2003", "author_list": "Washenfelder, R. A.; Wennberg, P. O.; et el." }, { "id": "https://authors.library.caltech.edu/records/s825y-bz795", "eprint_id": 59699, "eprint_status": "archive", "datestamp": "2023-09-15 05:05:45", "lastmod": "2023-10-23 21:13:36", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Dhaniyala-S", "name": { "family": "Dhaniyala", "given": "Suresh" } }, { "id": "Flagan-R-C", "name": { "family": "Flagan", "given": "Richard C." }, "orcid": "0000-0001-5690-770X" }, { "id": "McKinney-K-A", "name": { "family": "McKinney", "given": "Karena A." }, "orcid": "0000-0003-1129-1678" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "Novel Aerosol/Gas Inlet for Aircraft-Based Measurements", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 2003 American Association for Aerosol Research. \n\nReceived 18 July 2002; accepted 27 March 2003. \n\nThe authors would like to thank Fred Eisele, Nate Hazen, Jim Oliver, and Dave Tanner for their help in designing the inlet and Joe Haggerty for his expertise in fabricating the different inlet components. We would also like to thank Prof. Hans G. Hornung for valuable discussions about the inlet flow. We gratefully acknowledge the funding support of NASA (NAG5-7527) and NSF (ATM-9871353) for this project. POW also acknowledges funds provided by the Powell foundation.", "abstract": "A novel inlet has been designed for selective sampling of gas and aerosol phases of volatile species from high-speed aircraft. A multistage flow system brings the flow nearly isokinetically towards the sampling port. Two small airfoil-shaped \"blades\" are placed close to the sample port to provide the flow conditions required for aerosol and gas sampling. Aerosols are sampled when these blades are positioned to operate the inlet as a counterflow virtual impactor (CVI). The design enables sampling of particles as small as 0.1 w m from a high-speed aircraft under stratospheric conditions, a substantial improvement over that possible with previous CVI designs. For gas sampling, one of the blades is moved by a stepper motor to occlude the inlet opening and gas is sampled perpendicular to the bulk flow. Boundary layer suction is used to prevent the sampled gas from coming in contact with the impactor walls. This is one of the first designs of an inlet that enables gas sampling free of wall contact. The inlet was flown on the NASA ER-2 aircraft during the SOLVE 2000 campaign to study aerosol/gas partitioning of nitric acid in the lower stratosphere. Data from the flight tests show that the inlet flow characteristics are broadly in agreement with computational fluid dynamics (CFD) simulations.", "date": "2003-10", "date_type": "published", "publication": "Aerosol Science and Technology", "volume": "37", "number": "10", "publisher": "American Association for Aerosol Research", "pagerange": "828-840", "id_number": "CaltechAUTHORS:20150818-101521762", "issn": "0278-6826", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150818-101521762", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NAG5-7527" }, { "agency": "NSF", "grant_number": "ATM-9871353" }, { "agency": "Charles Lee Powell Foundation" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1080/02786820300937", "resource_type": "article", "pub_year": "2003", "author_list": "Dhaniyala, Suresh; Flagan, Richard C.; et el." }, { "id": "https://authors.library.caltech.edu/records/br1gf-42t23", "eprint_id": 35820, "eprint_status": "archive", "datestamp": "2023-08-22 00:50:28", "lastmod": "2023-10-20 21:14:12", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Rahn-T", "name": { "family": "Rahn", "given": "Thom" } }, { "id": "Eiler-J-M", "name": { "family": "Eiler", "given": "John M." } }, { "id": "Boering-K-A", "name": { "family": "Boering", "given": "Kristie A." } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" }, { "id": "McCarthy-M-C", "name": { "family": "McCarthy", "given": "Michael C." }, "orcid": "0000-0002-5450-5894" }, { "id": "Tyler-S", "name": { "family": "Tyler", "given": "Stanley" } }, { "id": "Schauffler-S-M", "name": { "family": "Schauffler", "given": "Sue" } }, { "id": "Donnelly-S", "name": { "family": "Donnelly", "given": "Stephen" } }, { "id": "Atlas-E-L", "name": { "family": "Atlas", "given": "Elliot" }, "orcid": "0000-0003-3847-5346" } ] }, "title": "Extreme deuterium enrichment in stratospheric hydrogen and the global atmospheric budget of H_2", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2003 Nature Publishing Group. \n\nReceived 24 January; accepted 15 July 2003. \n\nWe thank N. Kitchen for assistance in the laboratory. This study was supported in part by the NSF (T.A.R., K.A.B. and S.T.), the Davidow Fund and General Motors Corp. (J.M.E), the David and Lucile Packard Foundation (K.A.B.) and the NASA Upper Atmosphere Research Program (P.O.W., K.A.B, E.A, S.S. and S.D.). The National Centre for Atmospheric Research is operated by the University Corporation for Atmospheric Research under the sponsorship of the NSF. T.R. is the recipient of a Frederick Reines postdoctoral fellowship in experimental sciences awarded by Los Alamos National Laboratory.\n\nSupplemental Material - nature01917-s1.pdf
", "abstract": "Molecular hydrogen (H_2) is the second most abundant trace gas in the atmosphere after methane (CH_4). In the troposphere, the D/H ratio of H_2 is enriched by 120\u2030 relative to the world's oceans. This cannot be explained by the sources of H_2 for which the D/H ratio has been measured to date (for example, fossil fuels and biomass burning). But the isotopic composition of H_2 from its single largest source\u2014the photochemical oxidation of methane\u2014has yet to be determined. Here we show that the D/H ratio of stratospheric H2 develops enrichments greater than 440\u2030, the most extreme D/H enrichment observed in a terrestrial material. We estimate the D/H ratio of H_2 produced from CH_4 in the stratosphere, where production is isolated from the influences of non-photochemical sources and sinks, showing that the chain of reactions producing H_2 from CH_4 concentrates D in the product H_2. This enrichment, which we estimate is similar on a global average in the troposphere, contributes substantially to the D/H ratio of tropospheric H_2.", "date": "2003-08-21", "date_type": "published", "publication": "Nature", "volume": "424", "number": "6951", "publisher": "Nature Publishing Group", "pagerange": "918-921", "id_number": "CaltechAUTHORS:20121205-103720228", "issn": "0028-0836", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20121205-103720228", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF" }, { "agency": "Davidow Fund" }, { "agency": "General Motors Corporation" }, { "agency": "David and Lucile Packard Foundation" }, { "agency": "NASA" }, { "agency": "Los Alamos National Laboratory" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1038/nature01917", "primary_object": { "basename": "nature01917-s1.pdf", "url": "https://authors.library.caltech.edu/records/br1gf-42t23/files/nature01917-s1.pdf" }, "resource_type": "article", "pub_year": "2003", "author_list": "Rahn, Thom; Eiler, John M.; et el." }, { "id": "https://authors.library.caltech.edu/records/rnns9-st866", "eprint_id": 5263, "eprint_status": "archive", "datestamp": "2023-08-22 00:32:21", "lastmod": "2023-10-16 19:07:23", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Washenfelder-R-A", "name": { "family": "Washenfelder", "given": "R. A." }, "orcid": "0000-0002-8106-3702" }, { "id": "Roehl-C-M", "name": { "family": "Roehl", "given": "C. M." }, "orcid": "0000-0001-5383-8462" }, { "id": "McKinney-K-A", "name": { "family": "McKinney", "given": "K. A." }, "orcid": "0000-0003-1129-1678" }, { "id": "Julian-R-R", "name": { "family": "Julian", "given": "R. R." }, "orcid": "0000-0003-1580-8355" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "A compact, lightweight gas standards generator for permeation tubes", "ispublished": "pub", "full_text_status": "public", "keywords": "measurement standards; mass spectrometer accessories; aircraft instrumentation; heat of fusion; calibration; thermal stability; porosity", "note": "\u00a9 2003 American Institute of Physics. \n\n(Received 18 November 2002; accepted 17 February 2003) \n\nThe authors thank Dana Roth for his assistance in uncovering the history and properties of bismuth alloys. This material is based upon work supported by the National Science Foundation under Grant No. ATM9871353 and the National Aeronautics and Space Administration under Grant No. NAG5-7527.\n\nPublished - WASrsi03.pdf
", "abstract": "A lightweight, compact gas standards generator for permeation tubes is described. This system provides reliable temperature control during periods of intermittent power and is ideal for field measurements. A eutectic alloy with a high heat of fusion is used as a phase change material. This thermal source allows the system to maintain a constant permeation tube temperature of 46.6 \u00b0C for over 5 h in the absence of external power. This permeation system is currently being used in an aircraft chemical ionization mass spectrometer to provide HNO3 calibration.", "date": "2003-06", "date_type": "published", "publication": "Review of Scientific Instruments", "volume": "74", "number": "6", "publisher": "American Institute of Physics", "pagerange": "3151-3154", "id_number": "CaltechAUTHORS:WASrsi03", "issn": "0034-6748", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:WASrsi03", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "ATM-9871353" }, { "agency": "NASA", "grant_number": "NAG5-7527" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1063/1.1570949", "primary_object": { "basename": "WASrsi03.pdf", "url": "https://authors.library.caltech.edu/records/rnns9-st866/files/WASrsi03.pdf" }, "resource_type": "article", "pub_year": "2003", "author_list": "Washenfelder, R. A.; Roehl, C. M.; et el." }, { "id": "https://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.edu/records/06v0z-mw456", "eprint_id": 59681, "eprint_status": "archive", "datestamp": "2023-08-23 23:51:53", "lastmod": "2023-10-23 22:36:15", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Northway-M-J", "name": { "family": "Northway", "given": "M. J." } }, { "id": "Gao-R-S", "name": { "family": "Gao", "given": "R. S." } }, { "id": "Popp-P-J", "name": { "family": "Popp", "given": "P. J." } }, { "id": "Holecek-J-C", "name": { "family": "Holecek", "given": "J. C." } }, { "id": "Fahey-D-W", "name": { "family": "Fahey", "given": "D. W." } }, { "id": "Carslaw-K-S", "name": { "family": "Carslaw", "given": "K. S." } }, { "id": "Tolbert-M-A", "name": { "family": "Tolbert", "given": "M. A." } }, { "id": "Lait-L-R", "name": { "family": "Lait", "given": "L. R." } }, { "id": "Dhaniyala-S", "name": { "family": "Dhaniyala", "given": "S." } }, { "id": "Flagan-R-C", "name": { "family": "Flagan", "given": "R. C." }, "orcid": "0000-0001-5690-770X" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Mahoney-M-J", "name": { "family": "Mahoney", "given": "M. J." } }, { "id": "Herman-R-L", "name": { "family": "Herman", "given": "R. L." } }, { "id": "Toon-G-C", "name": { "family": "Toon", "given": "G. C." }, "orcid": "0000-0003-4174-7541" }, { "id": "Bui-T-P", "name": { "family": "Bui", "given": "T. P." } } ] }, "title": "An analysis of large HNO_3-containing particles sampled in the Arctic stratosphere during the winter of 1999/2000", "ispublished": "pub", "full_text_status": "public", "keywords": "polar stratospheric clouds; particles; denitrification; HNO_3; NAT; NO_y", "note": "\u00a9 2002 American Geophysical Union. \n\nReceived 9 July 2001; revised 28 November 2001; accepted 1 December 2002; published 24 October 2002. \n\nThe authors wish to thank the NASA ER-2 pilots J. Barrilleaux, J. Nystrom, and D. Porter and ground crew; Richard Winkler for his programming assistance; and Rich McLaughlin for assistance with Figure 2. This work was supported by the NASA Upper Atmosphere Research Program. Work at the Jet Propulsion Laboratory, California Institute of Technology, was carried out under contract with the National Aeronautics and Space Administration. Some of the material presented is based upon work supported by the National Science Foundation under award ATM-9871353, P. Wennberg, P.I.\n\nPublished - 185-Northway-2002.pdf
", "abstract": "Large (>2 \u03bcm diameter) HNO_3-containing polar stratospheric cloud (PSC) particles were measured in situ by the NOAA NO_y instrument on board the NASA ER-2 aircraft during seven flights in the 1999/2000 Arctic winter vortex. Here we discuss the detection of these large PSC particles, their spatial distribution, the ambient conditions under which they were detected, and our methods for interpreting NO_y time series with respect to particle sizes and number concentrations. The particles were observed through the use of two NO_y inlets on a particle separator extending below the ER-2 aircraft. The particle phase is assumed to be nitric acid trihydrate (NAT) or nitric acid dihydrate (NAD). Over a 48-day period, particles were sampled in the Arctic vortex over a broad range of latitudes (60\u201385\u00b0N) and altitudes (15\u201321 km). Typically, regions of the atmosphere up to 4 km above the observed large particle clouds were saturated with respect to NAT. Occasionally, large particles were measured in air subsaturated with respect to NAT, suggesting ongoing particle evaporation. Vortex minimum temperatures in the observation period suggest that synoptic-scale ice saturation conditions are not required for the formation of this type of particle. Three analytical methods are used to estimate size and number concentrations from the NO_y time series. Results indicate particle sizes between 5 and 20 \u03bcm diameter and concentrations from 10^(\u22125) to 10^(\u22123) cm^(\u22123). These low number concentrations imply a selective nucleation mechanism. Particle sizes and number concentrations were greater during the midwinter flights than the late winter flights. Knowledge of the geographical extent of large particles, actual sampling conditions, and particle size distributions offers multiple constraints for atmospheric models of PSC formation, which will lead to a better understanding of the process of denitrification and improvements in modeling future ozone loss.", "date": "2002-10-27", "date_type": "published", "publication": "Journal of Geophysical Research. Atmospheres", "volume": "107", "number": "D20", "publisher": "American Geophysical Union", "pagerange": "Art. No. 8298", "id_number": "CaltechAUTHORS:20150818-100656143", "issn": "2169-897X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150818-100656143", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA/JPL/Caltech" }, { "agency": "NSF", "grant_number": "ATM-9871353" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2001JD001079", "primary_object": { "basename": "185-Northway-2002.pdf", "url": "https://authors.library.caltech.edu/records/06v0z-mw456/files/185-Northway-2002.pdf" }, "resource_type": "article", "pub_year": "2002", "author_list": "Northway, M. J.; Gao, R. S.; et el." }, { "id": "https://authors.library.caltech.edu/records/w6kzm-d1123", "eprint_id": 46585, "eprint_status": "archive", "datestamp": "2023-08-22 01:29:14", "lastmod": "2023-10-26 19:51:22", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Rex-M", "name": { "family": "Rex", "given": "M." } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "Chemical depletion of Arctic ozone in winter 1999/2000", "ispublished": "pub", "full_text_status": "public", "keywords": "ozone; stratosphere; Match", "note": "\u00a9 2002 American Geophysical Union. \n\nReceived 12 February 2001; revised 2 July 2001; accepted 7 July 2001; published 20 September 2002. \n\nWe thank the THESEO 2000 core group, the\nSOLVE project scientists, and all personnel associated with the project management for making this campaign possible. We thank the innumerable people that made this study possible due to their dedication: the ground staff at the ozonesonde stations and at ESRANGE, the ER-2 and DC-8 personnel, and the ER-2 and DC-8 pilots. We thank the European Centre for Medium-Range Weather Forecasts for supplying the meteorological data. The ozonesondes used in THESEO 2000 were supported through the EC Environment Programme under contracts EVK2-CT-1999-00047 and through numerous national projects. The SOLVE effort was supported by the Upper Atmospheric Research Program, the Atmospheric Chemistry, Modeling and Analysis Program, and the Atmospheric Effects of Aviation Program of the U.S. National Aeronautics and Space Administration. The POAM III experiment is supported by the U.S. Office of Naval Research and NASA. Research at the Jet Propulsion Laboratory, California Institute of Technology, is performed under contract with the U.S. National Aeronautics and Space Administration. Work at the Alfred Wegener Institute was supported by the BMBF under the project 07ATC08.\n\nPublished - jgrd8865.pdf
", "abstract": "During Arctic winters with a cold, stable stratospheric circulation, reactions on the surface of polar stratospheric clouds (PSCs) lead to elevated abundances of chlorine monoxide (ClO) that, in the presence of sunlight, destroy ozone. Here we show that PSCs were more widespread during the 1999/2000 Arctic winter than for any other Arctic winter in the past two decades. We have used three fundamentally different approaches to derive the degree of chemical ozone loss from ozonesonde, balloon, aircraft, and satellite instruments. We show that the ozone losses derived from these different instruments and approaches agree very well, resulting in a high level of confidence in the results. Chemical processes led to a 70% reduction of ozone for a region \u223c1 km thick of the lower stratosphere, the largest degree of local loss ever reported for the Arctic. The Match analysis of ozonesonde data shows that the accumulated chemical loss of ozone inside the Arctic vortex totaled 117 \u00b1 14 Dobson units (DU) by the end of winter. This loss, combined with dynamical redistribution of air parcels, resulted in a 88 \u00b1 13 DU reduction in total column ozone compared to the amount that would have been present in the absence of any chemical loss. The chemical loss of ozone throughout the winter was nearly balanced by dynamical resupply of ozone to the vortex, resulting in a relatively constant value of total ozone of 340 \u00b1 50 DU between early January and late March. This observation of nearly constant total ozone in the Arctic vortex is in contrast to the increase of total column ozone between January and March that is observed during most years.", "date": "2002-09", "date_type": "published", "publication": "Journal of Geophysical Research D", "volume": "107", "number": "D20", "publisher": "American Geophysical Union", "pagerange": "Art. No. 8276", "id_number": "CaltechAUTHORS:20140701-070330116", "issn": "0148-0227", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140701-070330116", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "EC Environment Programme", "grant_number": "EVK2-CT-1999-00047" }, { "agency": "NASA/JPL/Caltech" }, { "agency": "Bundesministerium f\u00fcr Bildung und Forschung (BMBF)", "grant_number": "07ATC08" }, { "agency": "Office of Naval Research (ONR)" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2001JD000533", "primary_object": { "basename": "jgrd8865.pdf", "url": "https://authors.library.caltech.edu/records/w6kzm-d1123/files/jgrd8865.pdf" }, "resource_type": "article", "pub_year": "2002", "author_list": "Rex, M. and Wennberg, P." }, { "id": "https://authors.library.caltech.edu/records/hwbvx-jee66", "eprint_id": 46337, "eprint_status": "archive", "datestamp": "2023-08-22 01:28:14", "lastmod": "2023-10-26 19:40:53", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Salawitch-R-J", "name": { "family": "Salawitch", "given": "Ross J." } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" }, { "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-Francois" } } ] }, "title": "Near IR photolysis of HO_2NO_2: Implications for HO_x", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2002 by the American Geophysical Union. \n\nReceived 27 February 2002; revised 16 May 2002; accepted 21 May 2002; published 20 August 2002. \n\nWe thank Gary Knight and Coleen Roehl for\nmaking available measurements of HO_2NO_2 cross sections prior to publication\nand the anonymous reviewers for helpful comments. This work was\nfunded by the NASA Upper Atmosphere Research, Atmospheric Chemistry\nModeling and Analysis, and Atmospheric Effects of Aviation Programs.\nResearch at the Jet Propulsion Laboratory, California Institute of Technology,\nis performed under contract with the National Aeronautics and Space\nAdministration.\n\nPublished - grl15827.pdf
", "abstract": "We report observations and calculations of peroxynitric acid, HO_2NO_2, in the stratosphere and upper troposphere. The simulations show that photolysis of HO_2NO_2 via excitation of purely vibrational modes at wavelengths longward of 760 nm (the near IR) can dominate loss of this species. Consideration of this photolytic pathway reduces calculated HO_2NO_2, resolving a large discrepancy between standard model calculations and observations of HO_2NO_2 at high-latitude spring. The lower calculated abundance of HO_2NO_2 reduces the efficiency of the OH + HO_2NO_2 sink of HO_x. Consideration of this process leads to large increases in calculated HO_x (20 to 60%) for high-latitude spring and better agreement with observed stratospheric abundances of HO_x. Near IR photolysis of HO_2NO_2 alters the coupling between NO_x and HO_x in stratospheric and upper tropospheric photochemical models.", "date": "2002-08-15", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "29", "number": "16", "publisher": "American Geophysical Union", "pagerange": "Art. No. 1762", "id_number": "CaltechAUTHORS:20140618-120357826", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140618-120357826", "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": "10.1029/2002GL015006", "primary_object": { "basename": "grl15827.pdf", "url": "https://authors.library.caltech.edu/records/hwbvx-jee66/files/grl15827.pdf" }, "resource_type": "article", "pub_year": "2002", "author_list": "Salawitch, Ross J.; Wennberg, Paul O.; et el." }, { "id": "https://authors.library.caltech.edu/records/rpwas-ykg11", "eprint_id": 39385, "eprint_status": "archive", "datestamp": "2023-08-22 01:28:08", "lastmod": "2023-10-24 16:45:57", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Rahn-T", "name": { "family": "Rahn", "given": "T." } }, { "id": "Eiler-J-M", "name": { "family": "Eiler", "given": "J." } }, { "id": "McCarthy-M", "name": { "family": "McCarthy", "given": "M." } }, { "id": "Boering-K-A", "name": { "family": "Boering", "given": "K." } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P." }, "orcid": "0000-0002-6126-3854" }, { "id": "Atlas-E-L", "name": { "family": "Atlas", "given": "E." }, "orcid": "0000-0003-3847-5346" }, { "id": "Schauffler-S", "name": { "family": "Schauffler", "given": "S." } } ] }, "title": "The deuterium anomaly in stratospheric molecular hydrogen", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 2002 Published by Elsevier Ltd.", "abstract": "Molecular hydrogen (H_2) is the second most abundant\nreduced gas in the atmosphere (after methane) and has a\nglobally averaged mixing ratio of ~530 ppbv. Its recognized\nsources include: photochemical oxidation of CH_4 and nonmethane\nhydrocarbons (NMHC); biomass burning, fossil fuel\nburning, nitrogen fixation, and ocean degassing. The stable\nisotopic composition of H_2 can help quantify the relative\nimportance of these various sources and balancing sinks. The\naverage \u03b4D_(SMOW) of H_2 in the surface atmosphere is ca. + 100\n\u2030 - strongly D enriched compared to that measured for\natmospheric CH_4 \u03b4D_(SMOW) ~ -90 \u2030), expected for NMHC's,\nand known for combustion sources of H_2 \u03b4D_(SMOW) of ca. -200\nto -300 \u2030) [Gerst and Quay, 2001; Rahn et al., 2002]. The\nDIH ratios of H_2 from ocean degassing and nitrogen fixation\nare poorly known but are likely to have \u03b4D_(SMOW) values of ca. -\n700 \u2030, in near thermodynamic equilibrium with local H_2O.\nThus, all major sources of atmospheric H_2 are hundreds of\npermit poorer in D than H_2 itself. Either the loss processes\n(photo-oxidation and/or soil uptake) must discriminate against\nreaction with HD and/or isotopic fractionation associated with\nphoto-oxidation of CH_4 must favor production of HD over\nHH. Our current understanding of the global H_2 budget\ndepends strongly on the exact contribution of each of these\neffects to observed D enrichment.", "date": "2002-08-15", "date_type": "published", "publication": "Geochimica et Cosmochimica Acta", "volume": "66", "number": "S1", "publisher": "Elsevier", "pagerange": "A622-A622", "id_number": "CaltechAUTHORS:20130716-084852565", "issn": "0016-7037", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20130716-084852565", "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/S0016-7037(02)01012-8", "resource_type": "article", "pub_year": "2002", "author_list": "Rahn, T.; Eiler, J.; et el." }, { "id": "https://authors.library.caltech.edu/records/kdjp2-v3h74", "eprint_id": 46463, "eprint_status": "archive", "datestamp": "2023-08-22 01:23:34", "lastmod": "2023-10-26 19:46:04", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Yang-Zhonghua", "name": { "family": "Yang", "given": "Zhonghua" } }, { "id": "Toon-G-C", "name": { "family": "Toon", "given": "Geoffrey C." }, "orcid": "0000-0003-4174-7541" }, { "id": "Margolis-J-S", "name": { "family": "Margolis", "given": "Jack S." } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "Atmospheric CO_2 retrieved from ground-based near IR solar spectra", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2002 American Geophysical Union.\n\nReceived 7 December 2001; revised 9 March 2002; accepted 29 March 2002; published 14 May 2002.\n\nWe thank Yuk Yung, Linda Brown, Jim Randerson, Lloyd Wallace, Bill Livingston, and Mike Dulick for many\nhelpful discussions. Part of this work was performed at the Jet Propulsion Laboratory, California Institute of Technology, under contract with NASA. Paul Wennberg and Geoffrey Toon acknowledge support from NASA's upper Atmosphere Research Program. Zhonghua Yang is supported with a graduate research assistantship funded by NASA's ACMAP program (NAG5-11739).\n\nPublished - grl15614.pdf
", "abstract": "The column-averaged volume mixing ratio (VMR) of CO_2 over Kitt Peak, Arizona, has been retrieved from high-resolution solar absorption spectra obtained with the Fourier transform spectrometer on the McMath telescope. Simultaneous column measurements of CO_2 at \u223c6300 cm^\u22121 and O_2 at \u223c7900 cm^\u22121 were ratioed to minimize systematic errors. These column ratios were then scaled by the mean O_2 VMR (0.2095) to yield column-averaged vmrs of CO_2. These display similar behavior to the Mauna Loa in situ surface measurements. During the period 1977\u20131995, the column-averaged mixing ratio of CO_2 increased at an average rate of 1.49 \u00b1 0.04 ppmv/yr with seasonal variations of \u223c7 ppmv peak-to-peak. Our retrievals demonstrate that this remote technique is capable of precisions better than 0.5%.", "date": "2002-05", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "29", "number": "9", "publisher": "American Geophysical Union", "pagerange": "Art. No. 53", "id_number": "CaltechAUTHORS:20140624-094638500", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140624-094638500", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NAG5-11739" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2001GL014537", "primary_object": { "basename": "grl15614.pdf", "url": "https://authors.library.caltech.edu/records/kdjp2-v3h74/files/grl15614.pdf" }, "resource_type": "article", "pub_year": "2002", "author_list": "Yang, Zhonghua; Toon, Geoffrey C.; et el." }, { "id": "https://authors.library.caltech.edu/records/74bcj-82334", "eprint_id": 46610, "eprint_status": "archive", "datestamp": "2023-08-22 01:23:39", "lastmod": "2023-10-26 19:52:33", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Dhaniyala-S", "name": { "family": "Dhaniyala", "given": "Suresh" } }, { "id": "Mckinney-K-A", "name": { "family": "Mckinney", "given": "Karena A." } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "Lee-wave clouds and denitrification of the polar stratosphere", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2002 American Geophysical Union. \n\nReceived 7 August 2001; revised 30 October 2001; accepted 12 December 2001; published 10 May 2002. \n\nThe authors thank Leslie Lait, Paul Newman, and Mark Schoeberl for access to trajectory calculations via the NASA Goddard Automailer. We are grateful to Stefan Fueglistaler, Beiping Luo, David Fahey and Ross Salawitch for helpful comments that improved this manuscript. Finally, we thank Thomas Peter and an anonymous reviewer for their insightful comments.\n\nPublished - grl15218.pdf
", "abstract": "We present a hypothesis that the known formation of nitric acid hydrates in lee-wave ice clouds produces a \"standing crop\" of nitric acid trihydrate (NAT) particles, and that growth and sedimentation of these particles efficiently denitrifies the polar stratosphere. Simulations using a simple two-dimensional model illustrate that the large NAT number concentrations produced in lee waves (>0.1 cm^(\u22123)) lead to low gas-phase HNO_3 concentration in the cloud layer, limiting subsequent particle growth. Provided the NAT existence temperature is not exceeded, these particles slowly sediment out of the cloud layer, at which point further growth is initiated. As a result of the long residence time and vertical wind shear, NAT particles produced in geographically selective regions over a short duration can cause extensive denitrification throughout the lower stratosphere. Our model illustrates that a single hypothetical lee-wave nucleation event [10 hours, 1000 km width (along a longitude) \u00d7 100 m altitude] is sufficient to produce significant denitrification (\u223c25%) vortex-wide.", "date": "2002-05", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "29", "number": "9", "publisher": "American Geophysical Union", "pagerange": "Art. No. 1322", "id_number": "CaltechAUTHORS:20140701-144827393", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140701-144827393", "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": "10.1029/2001GL013900", "primary_object": { "basename": "grl15218.pdf", "url": "https://authors.library.caltech.edu/records/74bcj-82334/files/grl15218.pdf" }, "resource_type": "article", "pub_year": "2002", "author_list": "Dhaniyala, Suresh; Mckinney, Karena A.; et el." }, { "id": "https://authors.library.caltech.edu/records/p32q6-xk329", "eprint_id": 34252, "eprint_status": "archive", "datestamp": "2023-08-22 01:22:52", "lastmod": "2023-10-19 14:47:43", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Roehl-C-M", "name": { "family": "Roehl", "given": "Coleen M." }, "orcid": "0000-0001-5383-8462" }, { "id": "Nizkorodov-S-A", "name": { "family": "Nizkorodov", "given": "Sergey A." } }, { "id": "Zhang-Hui", "name": { "family": "Zhang", "given": "Hui" } }, { "id": "Blake-G-A", "name": { "family": "Blake", "given": "Geoffrey A." }, "orcid": "0000-0003-0787-1610" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "Photodissociation of Peroxynitric Acid in the Near-IR", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2002 American Chemical Society. Received: September 14, 2001; In Final Form: January 14, 2002. Publication Date (Web): March 21, 2002. This work was funded in part by NASA's Atmospheric Effects of Aviation Program (NAG5-9307;-11157) and by The National Science Foundation (ATM-9724500; -0094670). S.A.N. thanks the Camille and Henry Dreyfus Foundation for financial support.\n\nSupplemental Material - jp013536v_s.pdf
", "abstract": "Temperature-dependent near-IR photodissociation spectra were obtained for several vibrational overtone transitions of peroxynitric acid (HNO_4) with a tunable OPO photolysis/OH laser-induced-fluorescence system. Band-integrated photodissociation cross-sections (\u222b\u03c3_(diss)), determined relative to that for the 3\u03bd_1 OH stretching overtone, were measured for three dissociative bands. Assuming unit quantum efficiency for photodissociation of 3\u03bd_1 we find 2\u03bd_1 + \u03bd_3 (8242 cm^(-1)) = (1.21 \u00d7 10^(-20)) (independent of temperature), 2\u03bd_1 (6900 cm^(-1)) = 4.09 \u00d7 10^(-18)* e^((-826.5/T)) (295 K > T > 224 K), and \u03bd_1 + 2\u03bd_3 (6252 cm^(-1)) = 1.87 \u00d7 10^(-19)* e^((-1410.7/T)) (278 K > T > 240 K) cm^2 molecule^(-1) cm^(-1). The photodissociation cross-sections are independent of pressure over the range 2 to 40 Torr. Temperature-dependent quantum yields (\u03c6) for these transitions were obtained using integrated absorption cross-sections (\u222b\u03c3_(abs)) of HNO_4 overtone vibrations measured with a FTIR spectrometer. In the atmosphere, photodissociation in the infrared is dominated by excitation of the first overtone of the OH stretching vibration (2\u03bd_1). Inclusion of all dissociative HNO_4 overtone and combination transitions yields a daytime IR photolysis rate of approximately 1 \u00d7 10^(-5) s^(-1). This process significantly shortens the estimated lifetime of HNO_4 in the upper troposphere and lower stratosphere.", "date": "2002-04-18", "date_type": "published", "publication": "Journal of Physical Chemistry A", "volume": "106", "number": "5", "publisher": "American Chemical Society", "pagerange": "3766-3772", "id_number": "CaltechAUTHORS:20120920-075632571", "issn": "1089-5639", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20120920-075632571", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NAG5-9307" }, { "agency": "NASA", "grant_number": "NAG5-11157" }, { "agency": "NSF", "grant_number": "ATM-9724500" }, { "agency": "NSF", "grant_number": "ATM-0094670" }, { "agency": "Camille and Henry Dreyfus Foundation" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1021/jp013536v", "primary_object": { "basename": "jp013536v_s.pdf", "url": "https://authors.library.caltech.edu/records/p32q6-xk329/files/jp013536v_s.pdf" }, "resource_type": "article", "pub_year": "2002", "author_list": "Roehl, Coleen M.; Nizkorodov, Sergey A.; et el." }, { "id": "https://authors.library.caltech.edu/records/cqwck-46x18", "eprint_id": 46581, "eprint_status": "archive", "datestamp": "2023-08-22 01:22:08", "lastmod": "2023-10-26 19:51:12", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Danilin-M-Y", "name": { "family": "Danilin", "given": "M. Y." } }, { "id": "Ko-M-K-W", "name": { "family": "Ko", "given": "M. K. W." } }, { "id": "Bevilacqua-R-M", "name": { "family": "Bevilacqua", "given": "R. M." } }, { "id": "Lyjak-L-V", "name": { "family": "Lyjak", "given": "L. V." } }, { "id": "Froidevaux-L", "name": { "family": "Froidevaux", "given": "L." } }, { "id": "Santee-M-L", "name": { "family": "Santee", "given": "M. L." } }, { "id": "Zawodny-J-M", "name": { "family": "Zawodny", "given": "J. M." } }, { "id": "Hoppel-K-W", "name": { "family": "Hoppel", "given": "K. W." } }, { "id": "Richard-E-C", "name": { "family": "Richard", "given": "E. C." } }, { "id": "Spackman-J-R", "name": { "family": "Spackman", "given": "J. R." } }, { "id": "Weinstock-E-M", "name": { "family": "Weinstock", "given": "E. M." } }, { "id": "Herman-R-L", "name": { "family": "Herman", "given": "R. L." } }, { "id": "McKinney-K-A", "name": { "family": "McKinney", "given": "K. A." }, "orcid": "0000-0003-1129-1678" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Eisele-F-L", "name": { "family": "Eisele", "given": "F. L." } }, { "id": "Stimpfle-R-M", "name": { "family": "Stimpfle", "given": "R. M." } }, { "id": "Scott-C-J", "name": { "family": "Scott", "given": "C. J." } }, { "id": "Elkins-J-W", "name": { "family": "Elkins", "given": "J. W." } }, { "id": "Bui-T-V", "name": { "family": "Bui", "given": "T. V." } } ] }, "title": "Comparison of ER-2 aircraft and POAM III, MLS, and SAGE II satellite measurements during SOLVE using traditional correlative analysis and trajectory hunting technique", "ispublished": "pub", "full_text_status": "public", "keywords": "measurement comparison; trajectory hunting; correactive analysis; SOLVE", "note": "\u00a9 2002 American Geophysical Union. \n\nReceived 27 April 2001; revised 7 August 2001; accepted 19 September 2001; published 11 December 2002. \n\nWe thank R.J. Salawitch for providing the ER-2 merged files and D. W. Fahey, C. R. Webster, K. K. Perkins, J. C. Wilson, and D. G. Baumgardner for their instrument data used in our model initialization. We thank A. Tabazadeh for her STS code. Comments of two anonymous reviewers are appreciated. Work at AER, Inc., was supported by the UARS Guest Investigator Program (NAS5-98131) and NASA Atmospheric Chemistry and Model Analysis Program (NAS5-97039 and NAS1-00138). M.Y.D. acknowledges the travel support from the NASA Atmospheric Effects of Aviation Project for his involvement in SOLVE. L.V.L. is partially supported by the UARS Guest Investigator Program (S10109-X). Work at the Jet Propulsion Laboratory, California Institute of Technology, was done under contract with NASA. The ER-2 instrument coauthors acknowledge support from the NASA Upper Atmosphere Research Program. NCAR is supported by the National Science Foundation.\n\nPublished - jgrd9022.pdf
Erratum - jgrd9602.pdf
", "abstract": "We compared the version 5 Microwave Limb Sounder (MLS), version 3 Polar Ozone and Aerosol Measurement III (POAM III), version 6.0 Stratospheric Aerosol and Gas Experiment II (SAGE II), and NASA ER-2 aircraft measurements made in the Northern Hemisphere in January\u2013February 2000 during the SAGE III Ozone Loss and Validation Experiment (SOLVE). This study addresses one of the key scientific objectives of the SOLVE campaign, namely, to validate multiplatform satellite measurements made in the polar stratosphere during winter. This intercomparison was performed by using a traditional correlative analysis (TCA) and a trajectory hunting technique (THT). TCA compares profiles colocated within a chosen spatial-temporal vicinity. Launching backward and forward trajectories from the points of measurement, the THT identifies air parcels sampled at least twice within a prescribed match criterion during the course of 5 days. We found that the ozone measurements made by these four instruments agree most of the time within \u00b110% in the stratosphere up to 1400 K (\u223c35 km). The water vapor measurements from POAM III and the ER-2 Harvard Lyman \u03b1 hygrometer and Jet Propulsion Laboratory laser hygrometer agree to within \u00b10.5 ppmv (or about \u00b110%) in the lower stratosphere above 380 K. The MLS and ER-2 ClO measurements agree within their error bars for the TCA. The MLS and ER-2 nitric acid measurements near 17- to 20-km altitude agree within their uncertainties most of the time with a hint of a positive offset by MLS according to the TCA. We also applied the Atmospheric and Environmental Research, Inc. box model constrained by the ER-2 measurements for analysis of the ClO and HNO3 measurements using the THT. We found that: (1) the model values of ClO are smaller by about 0.3\u20130.4 (0.2) ppbv below (above) 400 K than those by MLS and (2) the HNO3 comparison shows a positive offset of MLS values by \u223c1 and 1\u20132 ppbv below 400 K and near 450 K, respectively. Our study shows that, with some limitations (like HNO3 comparison under polar stratospheric cloud conditions), the THT is a more powerful tool for validation studies than the TCA, making conclusions of the comparison statistically more robust.", "date": "2002-03-16", "date_type": "published", "publication": "Journal of Geophysical Research D", "volume": "107", "number": "D5", "publisher": "American Geophysical Union", "pagerange": "Art. No. SOL 58", "id_number": "CaltechAUTHORS:20140630-153240695", "issn": "0148-0227", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140630-153240695", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NAS5-98131" }, { "agency": "NASA", "grant_number": "NAS5-97039" }, { "agency": "NASA", "grant_number": "NAS1-00138" }, { "agency": "NASA", "grant_number": "S10109-X" }, { "agency": "NSF" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2001JD000781", "primary_object": { "basename": "jgrd9022.pdf", "url": "https://authors.library.caltech.edu/records/cqwck-46x18/files/jgrd9022.pdf" }, "related_objects": [ { "basename": "jgrd9602.pdf", "url": "https://authors.library.caltech.edu/records/cqwck-46x18/files/jgrd9602.pdf" } ], "resource_type": "article", "pub_year": "2002", "author_list": "Danilin, M. Y.; Ko, M. K. W.; et el." }, { "id": "https://authors.library.caltech.edu/records/96qaj-zm870", "eprint_id": 46460, "eprint_status": "archive", "datestamp": "2023-08-22 01:21:14", "lastmod": "2023-10-26 19:45:53", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Nizkorodov-S-A", "name": { "family": "Nizkorodov", "given": "Sergey A." } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "First Spectroscopic Observation of Gas-Phase HOONO", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 2002 American Chemical Society. \n\nReceived: September 21, 2001; In Final Form: November 28, 2001. \n\nThis work was funded in part by NASA's Atmospheric Effects of Aviation Program (NAG5-11157) and the National Science Foundation's Atmospheric Chemistry Program (ATM-0094670). The OPO laser system was developed with partial support from the National Science Foundation's Major Research Instrumentation Program (ATM-9724500; Geoffrey A. Blake, PI). S.A.N. thanks the Camille and Henry Dreyfus Foundation for support.", "abstract": "A vibrational overtone photodissociation spectrum of HOONO formed in the reaction of OH with NO_2 is reported. Rich vibrational structure, consistent with the existence of several HOONO conformers, is observed. A tentative vibrational assignment of the observed bands is proposed although complete assignment is not possible without further spectroscopic information. The ratio HOONO/HONO2 formed in the reaction of OH with NO_2 is estimated to be about 5% at 253 K and 20 Torr.", "date": "2002-02-14", "date_type": "published", "publication": "Journal of Physical Chemistry A", "volume": "106", "number": "6", "publisher": "American Chemical Society", "pagerange": "855-859", "id_number": "CaltechAUTHORS:20140624-094219203", "issn": "1089-5639", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140624-094219203", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NAG5-11157" }, { "agency": "NSF", "grant_number": "ATM-0094670" }, { "agency": "NSF", "grant_number": "ATM-9724500" }, { "agency": "Camille and Henry Dreyfus Foundation" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1021/jp013598l", "resource_type": "article", "pub_year": "2002", "author_list": "Nizkorodov, Sergey A. and Wennberg, Paul O." }, { "id": "https://authors.library.caltech.edu/records/z1nt8-vzt86", "eprint_id": 46473, "eprint_status": "archive", "datestamp": "2023-08-22 01:11:27", "lastmod": "2023-10-26 19:46:28", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Lanzerdorf-E-J", "name": { "family": "Lanzendorf", "given": "E. J." } }, { "id": "Hanisco-T-F", "name": { "family": "Hanisco", "given": "T. F." }, "orcid": "0000-0001-9434-8507" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Cohen-R-C", "name": { "family": "Cohen", "given": "R. C." }, "orcid": "0000-0001-6617-7691" }, { "id": "Stimpfle-R-M", "name": { "family": "Stimpfle", "given": "R. M." } }, { "id": "Anderson-J-G", "name": { "family": "Anderson", "given": "J. G." } } ] }, "title": "Comparing atmospheric [HO_2]/[OH] to modeled [HO_2]/[OH]: Identifying discrepancies with reaction rates", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2001 American Geophysical Union. \n\nReceived August 28, 2000; revised December 14, 2000; accepted December 18, 2000. \n\nPaper number 2000GL012264.\n\nPublished - grl14181.pdf
", "abstract": "Reactions that inter-convert OH and HO_2 are directly involved in the catalytic removal of O_3 in the lower stratosphere and in the catalytic production of O_3 in the upper troposphere. The agreement between the measured and modeled [HO_2]/[OH] tests our current understanding of this important chemistry. Recent changes to the recommended rate constants for OH+O_3 and HO_2+O_3 call into question how accurately the chemistry of the stratosphere is understood. [HO_2]/[OH] calculated with the new recommendations is 48% higher than the observations throughout the lower stratosphere, exceeding the uncertainty limits of the observations (20%). The extensive atmospheric data set allows tests of the rates of the individual processes that couple these free radicals. This work shows that the discrepancy is largest when the ratio is controlled by the reactions of OH and HO_2 with ozone.", "date": "2001-03-15", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "28", "number": "6", "publisher": "American Geophysical Union", "pagerange": "967-970", "id_number": "CaltechAUTHORS:20140624-130608495", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140624-130608495", "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": "10.1029/2000GL012264", "primary_object": { "basename": "grl14181.pdf", "url": "https://authors.library.caltech.edu/records/z1nt8-vzt86/files/grl14181.pdf" }, "resource_type": "article", "pub_year": "2001", "author_list": "Lanzendorf, E. J.; Hanisco, T. F.; et el." }, { "id": "https://authors.library.caltech.edu/records/8yv81-adq56", "eprint_id": 46498, "eprint_status": "archive", "datestamp": "2023-08-22 01:11:04", "lastmod": "2023-10-26 19:47:29", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Lanzendorf-E-J", "name": { "family": "Lanzendorf", "given": "E. J." } }, { "id": "Hanisco-T-F", "name": { "family": "Hanisco", "given": "T. F." }, "orcid": "0000-0001-9434-8507" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Cohen-R-C", "name": { "family": "Cohen", "given": "R. C." }, "orcid": "0000-0001-6617-7691" }, { "id": "Stimpfle-R-M", "name": { "family": "Stimpfle", "given": "R. M." } }, { "id": "Anderson-J-G", "name": { "family": "Anderson", "given": "J. G." } }, { "id": "Gao-R-S", "name": { "family": "Gao", "given": "R. S." } }, { "id": "Margitan-J-J", "name": { "family": "Margitan", "given": "J. J." } }, { "id": "Bui-T-P", "name": { "family": "Bui", "given": "T. P." } } ] }, "title": "Establishing the Dependence of [HO_2]/[OH] on Temperature, Halogen Loading, O_3, and NO_x Based on in Situ Measurements from the NASA ER-2", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 2001 American Chemical Society. \n\nReceived: July 3, 2000; in Final Form: October 18, 2000. \n\nWe thank the pilots and crew of the NASA ER-2. Thank you to C. R. Webster, R. D. May, and R. Herman for use of the ALIAS-CO measurements in this analysis and D. W. Fahey for use of the NO measurements. The ASHOE/MAESA, STRAT, and POLARIS ER-2 programs were supported by NASA through the Upper Atmosphere Research Program, the Atmospheric Effects of Aviation Project, and the Atmospheric Chemistry Modeling and Analysis Program.", "abstract": "In situ observations of OH and HO_2 from the Airborne Southern Hemisphere Ozone Experiment/Measurements for Assessing the Effects of Stratospheric Aircraft (ASHOE/MAESA), Stratospheric TRacers of Atmospheric Transport (STRAT), and Polar Ozone Loss in the Arctic Region in Summer (POLARIS) NASA ER-2 field campaigns are used to examine the partitioning of HO_x in the lower stratosphere (tropopause to ~21 km) and upper troposphere (~10 km to tropopause). These measurements span a latitude range from 70\u00b0S to 90\u00b0N and a variety of atmospheric conditions as a result of seasonal changes and altitude. The response of the observed [HO_2]/[OH] to changes in temperature, [O_3], [CO], [NO], [ClO], and [BrO] is investigated. The measured ratio is accurately described (~\u00b110%) by a steady-state model constrained by the measured mixing ratios of O_3, CO, NO, ClO, and BrO, where the model is valid for conditions of HO_x cycling much faster than HO_x production and loss. The concentration of HO_2 depends on [OH], which, to first order, has been observed to be a simple function of the solar zenith angle in the lower stratosphere.^1 The partitioning between OH and HO_2 is controlled by the local chemistry between the HO_x radicals and O_3, CO, NO, ClO, and BrO. The response of [HO_x] to changes in [NO_x] and [O_3] is demonstrated. Further observations are necessary to illustrate the response of HOx to changes in halogen concentrations. A quantitative understanding of [HO_2]/[OH] is important, since many of the reactions that control this ratio are directly involved in catalytic removal of O_3 in the lower stratosphere and production of O_3 in the upper troposphere.", "date": "2001-03-08", "date_type": "published", "publication": "Journal of Physical Chemistry A", "volume": "105", "number": "9", "publisher": "American Chemical Society", "pagerange": "1535-1542", "id_number": "CaltechAUTHORS:20140625-094855154", "issn": "1089-5639", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140625-094855154", "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": "10.1021/jp002384l", "resource_type": "article", "pub_year": "2001", "author_list": "Lanzendorf, E. J.; Hanisco, T. F.; et el." }, { "id": "https://authors.library.caltech.edu/records/1c79a-04v62", "eprint_id": 46461, "eprint_status": "archive", "datestamp": "2023-08-22 01:10:55", "lastmod": "2023-10-26 19:45:57", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "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": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Perkins-K-K", "name": { "family": "Perkins", "given": "K. K." } }, { "id": "Stimpfle-R-M", "name": { "family": "Stimpfle", "given": "R. M." } }, { "id": "Voss-P-B", "name": { "family": "Voss", "given": "P. B." } }, { "id": "Anderson-J-G", "name": { "family": "Anderson", "given": "J. G." } }, { "id": "Cohen-R-C", "name": { "family": "Cohen", "given": "R. C." }, "orcid": "0000-0001-6617-7691" }, { "id": "Fahey-D-W", "name": { "family": "Fahey", "given": "D. W." } }, { "id": "Gao-R-S", "name": { "family": "Gao", "given": "R. S." } }, { "id": "Hintsa-E-J", "name": { "family": "Hintsa", "given": "E. J." } }, { "id": "Salawitch-R-J", "name": { "family": "Salawitch", "given": "R. J." } }, { "id": "Margitan-J-J", "name": { "family": "Margitan", "given": "J. J." } }, { "id": "McElroy-C-T", "name": { "family": "McElroy", "given": "C. T." } }, { "id": "Midwinter-C", "name": { "family": "Midwinter", "given": "C." } } ] }, "title": "Sources, Sinks, and the Distribution of OH in the Lower Stratosphere", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 2001 American Chemical Society. \n\nReceived: July 3, 2000; In Final Form: October 18, 2000.\n\nWe thank the pilots and crew of the NASA ER-2 and the logistical support of NASA AMES. This work was supported by the NASA Upper Atmospheric Research Program and the Atmospheric Effects of Aviation Project.", "abstract": "Extensive measurement campaigns by the NASA ER-2 research aircraft have obtained a nearly pole-to-pole database of the species that control HO_x (OH + HO_2) chemistry. The wide dynamic range of these in situ measurements provides an opportunity to demonstrate empirically the mechanisms that control the HO_x system. Measurements in the lower stratosphere show a remarkably tight correlation of OH concentration with the solar zenith angle (SZA). This correlation is nearly invariant over latitudes ranging from 70\u00b0 S to 90\u00b0 N and all seasons. An analysis of the production and loss of HO_x in terms of the rate determining steps of reaction sequences developed by Johnston and Podolske and Johnston and Kinnison is used to clarify the behavior of the system and to directly test our understanding of the system with observations. Calculations using in situ measurements show that the production rate of HOx is proportional to O3 and ultraviolet radiation flux. The loss rate is proportional to the concentration and the partitioning of NO_y (reactive nitrogen) and the concentration of HO_2. In the absence of heterogeneous reactions, the partitioning of NO_y is controlled by O_3 and HO_x and the concentration of HO2 is controlled by NO_y and O_3, so that the removal rate of OH is buffered against changes in the correlation of O_3 and NO_y. The heterogeneous conversion of NO_2 to HNO_3 is not an important net source of HO_x because production and removal sequences are nearly balanced. Changes in NOy partitioning resulting from heterogeneous chemistry have a large effect on the loss rates of HO_x, but little or no impact on the measured abundance of OH. The enhanced loss rates at high NO_2/HNO_3 are offset in the data set examined here by enhanced production rates resulting from increased photolysis rates resulting from the decreased O_3 column above the ER-2.", "date": "2001-03-08", "date_type": "published", "publication": "Journal of Physical Chemistry A", "volume": "105", "number": "9", "publisher": "American Chemical Society", "pagerange": "1543-1553", "id_number": "CaltechAUTHORS:20140624-094317565", "issn": "1089-5639", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140624-094317565", "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": "10.1021/jp002334g", "resource_type": "article", "pub_year": "2001", "author_list": "Hanisco, T. F.; Lanzendorf, E. J.; et el." }, { "id": "https://authors.library.caltech.edu/records/dxf8c-9rq45", "eprint_id": 46500, "eprint_status": "archive", "datestamp": "2023-08-22 01:11:13", "lastmod": "2023-10-26 19:47:37", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Perkins-K-K", "name": { "family": "Perkins", "given": "K. K." } }, { "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": "Koch-L-C", "name": { "family": "Koch", "given": "L. C." } }, { "id": "Stimpfle-R-M", "name": { "family": "Stimpfle", "given": "R. M." } }, { "id": "Voss-P-B", "name": { "family": "Voss", "given": "P. B." } }, { "id": "Bonne-G-P", "name": { "family": "Bonne", "given": "G. P." } }, { "id": "Lanzendorf-E-J", "name": { "family": "Lanzendorf", "given": "E. J." } }, { "id": "Anderson-J-G", "name": { "family": "Anderson", "given": "J. G." } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Gao-R-S", "name": { "family": "Gao", "given": "R. S." } }, { "id": "Del-Negro-L-A", "name": { "family": "Del Negro", "given": "L. A." } }, { "id": "Salawitch-R-J", "name": { "family": "Salawitch", "given": "R. J." } }, { "id": "McElroy-C-T", "name": { "family": "McElroy", "given": "C. T." } }, { "id": "Hintsa-E-J", "name": { "family": "Hintsa", "given": "E. J." } }, { "id": "Loewenstein-M", "name": { "family": "Loewenstein", "given": "M." } }, { "id": "Bui-T-P", "name": { "family": "Bui", "given": "T. P." } } ] }, "title": "The NO_x-HNO_3 System in the Lower Stratosphere: Insights from In Situ Measurements and Implications of the J_(HNO_3)-[OH] Relationship", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 2001 American Chemical Society. \n\nPublication Date (Web): January 5, 2001. Received: July 14, 2000; In Final Form: November 2, 2000. \n\nWe thank the NASA Upper Atmospheric Research Program and Atmospheric Effects of Aviation Project for supporting the POLARIS field campaign. The development of the new ClO/ClONO_2/NO_2 instrument was supported by the NASA Upper Atmospheric Research Program and Environmental Research Aircraft and Sensor Technology programs. K.K.P. gratefully acknowledges a graduate fellowship from NSF. We also thank P. A. Newman, L. R. Lait, and M. R. Schoberl for providing the back-trajectory calculations, C. R. Webster for providing N_2O^(ALIAS), J. C. Wilson for providing aerosol surface area density, and E. R. Nash for providing the climatological mean temperatures. Lastly, we thank N. M. Donahue for his useful input on this manuscript.", "abstract": "During the 1997 Photochemistry of Ozone Loss in the Arctic Region in Summer (POLARIS) mission, simultaneous in situ observations of NO_x and HO_x radicals, their precursors, and the radiation field were obtained in the lower stratosphere. We use these observations to evaluate the primary mechanisms that control NO_x\u2212HNO_3 exchange and to understand their control over the partitioning between NO_2 and HNO_3 in regions of continuous sunlight. We calculate NO_x production (P_(NO)_x) and loss (L_(NO)_x) in a manner directly constrained by the in situ measurements and current rate constant recommendations, using approaches for representing albedo, overhead O_3 and [OH] that reduce model uncertainty. We find a consistent discrepancy of 18% between modeled rates of NO_x production and loss (L_(NO)_x = 1.18P_(NO)_x) which is within the measurement uncertainty of \u00b127%. The partitioning between NO_x production processes is [HNO_3 + OH (41 \u00b1 2)%; HNO+3 + h\u03bd (59 \u00b1 2)%] and between NO_x loss processes is [NO_2 + OH, 90% to >97%; BrONO_2 + H_2O, 10% to <3%]. The steady-state description of NO_x\u2212HNO_3 exchange reveals the significant influence of the tight correlation between the photolysis rate of HNO_3 and [OH] established by in situ measurements throughout the lower stratosphere. Parametrizing this relationship, we find (1) the steady-state value of [NO_2]_(24h-avg)/[HNO_3] in the continuously sunlit, lower stratosphere is a function only of temperature and number density, and (2) the partitioning of NO_x production between HNO_3 + OH and HNO_3 + h\u03bd is nearly constant throughout most of the lower stratosphere. We describe a methodology (functions of latitude, day, temperature, and pressure) for accurately predicting the steady-state value of [NO_2]_(24h-avg)/[HNO_3] and the partitioning of NO_x production within these regions. The results establish a metric to compare observations of [NO_2]_(24h-avg)/[HNO_3] within the continuously sunlit region and provide a simple diagnostic for evaluating the accuracy of models that attempt to describe the coupled NO_x\u2212HO_x photochemistry in the lower stratosphere.", "date": "2001-03-08", "date_type": "published", "publication": "Journal of Physical Chemistry A", "volume": "105", "number": "9", "publisher": "American Chemical Society", "pagerange": "1521-1534", "id_number": "CaltechAUTHORS:20140625-103136729", "issn": "1089-5639", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140625-103136729", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA" }, { "agency": "NSF Graduate Research Fellowship" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1021/jp002519n", "resource_type": "article", "pub_year": "2001", "author_list": "Perkins, K. K.; Hanisco, T. F.; et el." }, { "id": "https://authors.library.caltech.edu/records/czfkb-mvn20", "eprint_id": 46476, "eprint_status": "archive", "datestamp": "2023-08-22 01:10:21", "lastmod": "2023-10-26 19:46:37", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Jaegl\u00e9-L", "name": { "family": "Jaegl\u00e9", "given": "Lyatt" } }, { "id": "Jacob-D-J", "name": { "family": "Jacob", "given": "Daniel J." }, "orcid": "0000-0002-6373-3100" }, { "id": "Brune-W-H", "name": { "family": "Brune", "given": "William H." }, "orcid": "0000-0002-1609-4051" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "Chemistry of HO_x radicals in the upper troposphere", "ispublished": "pub", "full_text_status": "restricted", "keywords": "Hydrogen oxides; Nitrogen oxides; Tropospheric ozone; Upper troposphere; Aircraft measurements", "note": "\u00a9 2000 Elsevier Science Ltd. \n\nReceived 1 March 2000; accepted 5 July 2000. \n\nThis work was supported by the National Science Foundation (NSF) and by the National Aeronautics and Space Administration (NASA).", "abstract": "Aircraft observations from three recent missions (STRAT, SUCCESS, SONEX) are synthesized into a theoretical analysis of the factors controlling the concentrations of HO_x radicals (HO_x=OH+peroxy) and the larger reservoir family HO_y (HO_y=HO_x+2H_2O_2+2CH_3OOH+HNO_2+HNO_4) in the upper troposphere. Photochemical model calculations capture 66% of the variance of observed HOx concentrations. Two master variables are found to determine the variance of the 24 h average HOx concentrations: the primary HO_x production rate, P(HO_x), and the concentration of nitrogen oxide radicals (NO_x=NO+NO_2). We use these two variables as a coordinate system to diagnose the photochemistry of the upper troposphere and map the different chemical regimes. Primary HO_x production is dominated by the O(^1D)+H_2O reaction when [H_2O]>100 ppmv, and by photolysis of acetone (and possibly other convected HO_x precursors) under drier conditions. For the principally northern midlatitude conditions sampled by the aircraft missions, the HO_x yield from acetone photolysis ranges from 2 to 3. Methane oxidation amplifies the primary HO_x source by a factor of 1.1\u20131.9. Chemical cycling within the HO_x family has a chain length of 2.5\u20137, while cycling between the HO_x family and its HO_y reservoirs has a chain length of 1.6\u20132.2. The number of ozone molecules produced per HO_y molecule consumed ranges from 4 to 12, such that ozone production rates vary between 0.3 and 5 ppbv d^(\u22121) in the upper troposphere. Three chemical regimes (NO_x-limited, transition, NO_x-saturated) are identified to describe the dependence of HO_x concentrations and ozone production rates on the two master variables P(HO_x) and [NO_x]. Simplified analytical expressions are derived to express these dependences as power laws for each regime. By applying an eigenlifetime analysis to the HO_x\u2013NO_x\u2013O_3 chemical system, we find that the decay of a perturbation to HO_y in the upper troposphere (as from deep convection) is represented by four dominant modes with the longest time scale being factors of 2\u20133 times longer than the steady-state lifetime of HO_y.", "date": "2001-03", "date_type": "published", "publication": "Atmospheric Environment", "volume": "35", "number": "3", "publisher": "Elsevier", "pagerange": "469-489", "id_number": "CaltechAUTHORS:20140624-132838956", "issn": "1352-2310", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140624-132838956", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF" }, { "agency": "NASA" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1016/S1352-2310(00)00376-9", "resource_type": "article", "pub_year": "2001", "author_list": "Jaegl\u00e9, Lyatt; Jacob, Daniel J.; et el." }, { "id": "https://authors.library.caltech.edu/records/gtans-70h33", "eprint_id": 46336, "eprint_status": "archive", "datestamp": "2023-08-22 01:09:50", "lastmod": "2023-10-26 19:40:49", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Fahey-D-W", "name": { "family": "Fahey", "given": "D. W." } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "The Detection of Large HNO_3-Containing Particles in the Winter Arctic Stratosphere", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 2001 American Association for the Advancement of Science. \n\nReceived 7 November 2000; accepted 9 January 2001. \n\nWe appreciate the contributions of J. Barrilleaux, J. Nystrom, and D. Porter as NASA ER-2 pilots; of L. Lait in producing Fig. 1; and of B. P. Luo in discussions of the statistical evaluation of the particle size distributions. The NASA Upper Atmosphere Research Program supported this research.", "abstract": "Large particles containing nitric acid (HNO_3) were observed in the 1999/2000 Arctic winter stratosphere. These in situ observations were made over a large altitude range (16 to 21 kilometers) and horizontal extent (1800 kilometers) on several airborne sampling flights during a period of several weeks. With diameters of 10 to 20 micrometers, these sedimenting particles have significant potential to denitrify the lower stratosphere. A microphysical model of nitric acid trihydrate particles is able to simulate the growth and sedimentation of these large sizes in the lower stratosphere, but the nucleation process is not yet known. Accurate modeling of the formation of these large particles is essential for understanding Arctic denitrification and predicting future Arctic ozone abundances.", "date": "2001-02-09", "date_type": "published", "publication": "Science", "volume": "291", "number": "5506", "publisher": "American Association for the Advancement of Science", "pagerange": "1026-1031", "id_number": "CaltechAUTHORS:20140618-114453557", "issn": "0036-8075", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140618-114453557", "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.1057265", "resource_type": "article", "pub_year": "2001", "author_list": "Fahey, D. W. and Wennberg, P. O." }, { "id": "https://authors.library.caltech.edu/records/xev6x-psq09", "eprint_id": 46497, "eprint_status": "archive", "datestamp": "2023-08-22 01:09:05", "lastmod": "2023-10-26 19:47:25", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Voss-P-B", "name": { "family": "Voss", "given": "P. B." } }, { "id": "Stimpfle-R-M", "name": { "family": "Stimpfle", "given": "R. M." } }, { "id": "Cohen-R-C", "name": { "family": "Cohen", "given": "R. C." }, "orcid": "0000-0001-6617-7691" }, { "id": "Hanisco-T-F", "name": { "family": "Hanisco", "given": "T. F." }, "orcid": "0000-0001-9434-8507" }, { "id": "Bonne-G-P", "name": { "family": "Bonne", "given": "G. P." } }, { "id": "Perkins-K-K", "name": { "family": "Perkins", "given": "K. K." } }, { "id": "Lanzendorf-E-J", "name": { "family": "Lanzendorf", "given": "E. J." } }, { "id": "Anderson-J-G", "name": { "family": "Anderson", "given": "J. G." } }, { "id": "Salawitch-R-J", "name": { "family": "Salawitch", "given": "R. J." } }, { "id": "Webster-C-R", "name": { "family": "Webster", "given": "C. R." } }, { "id": "Scott-D-C", "name": { "family": "Scott", "given": "D. C." } }, { "id": "May-R-D", "name": { "family": "May", "given": "R. D." } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Newman-P-A", "name": { "family": "Newman", "given": "P. A." } }, { "id": "Lait-L-R", "name": { "family": "Lait", "given": "L. R." } }, { "id": "Elkins-J-W", "name": { "family": "Elkins", "given": "J. W." } }, { "id": "Bui-T-P", "name": { "family": "Bui", "given": "T. P." } } ] }, "title": "Inorganic chlorine partitioning in the summer lower stratosphere: Modeled and measured [ClONO_2]/[HCl] during POLARIS", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2001 American Geophysical Union. \n\nReceived March 14, 2000; revised July 24, 2000; accepted August 8, 2000. Paper number 2000JD900494. \n\nWe thank NASA's Upper Atmosphere Research Program as well as the researchers pilots, crew, and managers of NASA's ER-2 program for supporting the POLARIS campaign. This work was funded under NASA grants NAG-1-2007 and NAG-2-1300. We thank J. J. Margitan for the ER-2 O_3 data. P. B. Voss is grateful for support from NASA's Global Change Fellowship Program.\n\nPublished - jgrd7993.pdf
", "abstract": "We examine inorganic chlorine (Cl_y,) partitioning in the summer lower stratosphere using in situ ER-2 aircraft observations made during the Photochemistry of Ozone Loss in the Arctic Region in Summer (POLARIS) campaign. New steady state and numerical models estimate [ClONO_2]/[HCl] using currently accepted photochemistry. These models are tightly constrained by observations with OH (parameterized as a function of solar zenith angle) substituting for modeled HO_2 chemistry. We find that inorganic chlorine photochemistry alone overestimates observed [ClONO_2]/[HCl] by approximately 55\u201360% at mid and high latitudes. On the basis of POLARIS studies of the inorganic chlorine budget, [ClO]/[ClONO_2], and an intercomparison with balloon observations, the most direct explanation for the model-measurement discrepancy in Cl_y, partitioning is an error in the reactions, rate constants, and measured species concentrations linking HCl and ClO (simulated [ClO]/[HCl] too high) in combination with a possible systematic error in the ER-2 ClONO_2 measurement (too low). The high precision of our simulation (\u00b115% 1\u03c3 for [ClONO_2]/[HCl], which is compared with observations) increases confidence in the observations, photolysis calculations, and laboratory rate constants. These results, along with other findings, should lead to improvements in both the accuracy and precision of stratospheric photochemical models.", "date": "2001-01-27", "date_type": "published", "publication": "Journal of Geophysical Research D", "volume": "106", "number": "D2", "publisher": "American Geophysical Union", "pagerange": "1713-1732", "id_number": "CaltechAUTHORS:20140625-083843890", "issn": "0148-0227", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140625-083843890", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NAG-1-2007" }, { "agency": "NASA", "grant_number": "NAG-2-1300" }, { "agency": "NASA Global Change Fellowship" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2000JD900494", "primary_object": { "basename": "jgrd7993.pdf", "url": "https://authors.library.caltech.edu/records/xev6x-psq09/files/jgrd7993.pdf" }, "resource_type": "article", "pub_year": "2001", "author_list": "Voss, P. B.; Stimpfle, R. M.; et el." }, { "id": "https://authors.library.caltech.edu/records/2f6hh-1m737", "eprint_id": 46462, "eprint_status": "archive", "datestamp": "2023-08-22 01:05:29", "lastmod": "2023-10-26 19:46:02", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Cohen-R-C", "name": { "family": "Cohen", "given": "R. C." }, "orcid": "0000-0001-6617-7691" }, { "id": "Perkins-K-K", "name": { "family": "Perkins", "given": "K. K." } }, { "id": "Koch-L-C", "name": { "family": "Koch", "given": "L. C." } }, { "id": "Stimpfle-R-M", "name": { "family": "Stimpfle", "given": "R. M." } }, { "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": "Bonne-G-P", "name": { "family": "Bonne", "given": "G. P." } }, { "id": "Voss-P-B", "name": { "family": "Voss", "given": "P. B." } }, { "id": "Salawitch-R-J", "name": { "family": "Salawitch", "given": "R. J." } }, { "id": "Del-Negro-L-A", "name": { "family": "Del Negro", "given": "L. A." } }, { "id": "Wilson-J-C", "name": { "family": "Wilson", "given": "J. C." } }, { "id": "McElroy-C-T", "name": { "family": "McElroy", "given": "C. T." } }, { "id": "Bui-T-P", "name": { "family": "Bui", "given": "T. P." } } ] }, "title": "Quantitative constraints on the atmospheric chemistry of nitrogen oxides: An analysis along chemical coordinates", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2000 American Geophysical Union. \n\nManuscript Accepted: 8 May 2000; Manuscript Received: 23 February 2000. Paper number 2000JD900290. \n\nThe POLARIS experiments were supported by the NASA Upper Atmospheric Research Program and Atmospheric Effects of Aviation Project (M. Kurylo, P. DeCola, and R. Kawa, project managers). The ClO/ClONO_2/NO_2 instrument was developed with the support of the NASA Upper Atmospheric\nResearch Program and the NASA Environmental Research Aircraft and Sensor Technology programs. Analyses presented in this paper were supported by NASA AEAP. K.K.P gratefully acknowledges an NSF graduate fellowship.We gratefully acknowledge the use of 0_3 measurements obtained by J. J. Margitan and M. H. Proffitt, Chuck Brock's contribution to the aerosol measurements and both experimental contributions to NO, NO_2, and NO_y measurements, and comments on this paper by David Fahey and Ru-Shan Gao.\n\nPublished - jgrd7650.pdf
", "abstract": "In situ observations Of NO_2, NO, NO_y, ClONO_2, OH, O_3, aerosol surface area, spectrally resolved solar radiation, pressure and temperature obtained from the ER-2 aircraft during the Photochemistry of Ozone Loss in the Arctic Region in Summer (POLARIS) experiments are used to examine the factors controlling the fast photochemistry connecting NO and NO_2 and the slower chemistry connecting NO_x and HNO_3. Our analysis uses \"chemical coordinates\" to examine gradients of the difference between a model and precisely calibrated measurements to provide a quantitative assessment of the accuracy of current photochemical models. The NO/NO_2 analysis suggests that reducing the activation energy for the NO+O_3 reaction by 1.7 kJ/mol will improve model representation of the temperature dependence of the NO/NO_2 ratio in the range 215\u2013235 K. The NO_x/HNO_3 analysis shows that systematic errors in the relative rate coefficients used to describe NO_x loss by the reaction OH + NO_2 \u2192 HNO_3 and by the reaction set NO_2 + O_3 \u2192 NO_3; NO_2 + NO_3 \u2192 N_(2)O_5; N_(2)O_5 + H_(2)O \u2192 2HNO_3 are in error by +8.4% (+30/\u221245%) (OH+NO_2 too fast) in models using the Jet Propulsion Laboratory 1997 recommendations [DeMore et al., 1997]. Models that use recommendations for OH+NO2 and OH+HNO_3 based on reanalysis of recent and past laboratory measurements are in error by 1.2% (+30/\u221245%) (OH+NO_2 too slow). The +30%/\u221245% error limit reflects systematic uncertainties, while the statistical uncertainty is 0.65%. This analysis also shows that the POLARIS observations only modestly constrain the relative rates of the major NO_x production reactions HNO3 + OH \u2192 H_(2)O + NO_3 and HNO_3 + h\u03bd \u2192 OH + NO_2. Even under the assumption that all other aspects of the model are perfect, the POLARIS observations only constrain the rate coefficient for OH+HNO_3 to a range of 65% around the currently recommended value.", "date": "2000-10-16", "date_type": "published", "publication": "Journal of Geophysical Research D", "volume": "105", "number": "D19", "publisher": "American Geophysical Union", "pagerange": "24283-24304", "id_number": "CaltechAUTHORS:20140624-094548081", "issn": "0148-0227", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140624-094548081", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA" }, { "agency": "NSF Graduate Research Fellowship" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2000JD900290", "primary_object": { "basename": "jgrd7650.pdf", "url": "https://authors.library.caltech.edu/records/2f6hh-1m737/files/jgrd7650.pdf" }, "resource_type": "article", "pub_year": "2000", "author_list": "Cohen, R. C.; Perkins, K. K.; et el." }, { "id": "https://authors.library.caltech.edu/records/zmy0k-kpb71", "eprint_id": 46464, "eprint_status": "archive", "datestamp": "2023-08-22 01:04:09", "lastmod": "2023-10-26 19:46:06", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Fahey-D-W", "name": { "family": "Fahey", "given": "D. W." } }, { "id": "Gao-R-S", "name": { "family": "Gao", "given": "R. S." } }, { "id": "Del-Negro-L-A", "name": { "family": "Del Negro", "given": "L. A." } }, { "id": "Keim-E-R", "name": { "family": "Keim", "given": "E. R." } }, { "id": "Kawa-S-R", "name": { "family": "Kawa", "given": "S. R." } }, { "id": "Salawitch-R-J", "name": { "family": "Salawitch", "given": "R. 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": "Perkins-K-K", "name": { "family": "Perkins", "given": "K. K." } }, { "id": "Lloyd-S-A", "name": { "family": "Lloyd", "given": "S. A." } }, { "id": "Swartz-W-H", "name": { "family": "Swartz", "given": "W. H." } }, { "id": "Proffitt-M-H", "name": { "family": "Proffitt", "given": "M. H." } }, { "id": "Margitan-J-J", "name": { "family": "Margitan", "given": "J. J." } }, { "id": "Wilson-J-C", "name": { "family": "Wilson", "given": "J. C." } }, { "id": "Stimpfle-R-M", "name": { "family": "Stimpfle", "given": "R. M." } }, { "id": "Cohen-R-C", "name": { "family": "Cohen", "given": "R. C." }, "orcid": "0000-0001-6617-7691" }, { "id": "McElroy-C-T", "name": { "family": "McElroy", "given": "C. T." } }, { "id": "Webster-C-R", "name": { "family": "Webster", "given": "C. R." } }, { "id": "Loewenstein-M", "name": { "family": "Loewenstein", "given": "M." } }, { "id": "Elkins-J-W", "name": { "family": "Elkins", "given": "J. W." } }, { "id": "Bui-T-P", "name": { "family": "Bui", "given": "T. P." } } ] }, "title": "Ozone destruction and production rates between spring and autumn in the Arctic stratosphere", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2000 American Geophysical Union. \n\nReceived January 17, 2000; revised May 26, 2000; accepted June 1 2000. \n\nThe authors are grateful for support from the NASA Upper Atmospheric Research Program and the Atmospheric Effects of Aviation Project, to J. A. Logan for O_3 data, to P. A. Newman for back trajectories, and to S. G. Donnelly for instrument support.\n\nPublished - grl13647.pdf
", "abstract": "In situ measurements of radical and long-lived species were made in the lower Arctic stratosphere (18 to 20 km) between spring and early autumn in 1997. The measurements include O_3, ClO, OH, HO_2, NO, NO_2, N_(2)O, CO, and overhead O_3. A photochemical box model constrained by these and other observations is used to compute the diurnally averaged destruction and production rates of O3 in this region. The rates show a strong dependence on solar exposure and ambient O_3. Total destruction rates, which reach 19%/month in summer, reveal the predominant role of NO_x and HO_x catalytic cycles throughout the period. Production of O_3 is significant only in midsummer air parcels. A comparison of observed O_3 changes with destruction rates and transport effects indicates the predominant role of destruction in spring and an increased role of transport by early autumn.", "date": "2000-09-01", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "27", "number": "17", "publisher": "American Geophysical Union", "pagerange": "2605-2608", "id_number": "CaltechAUTHORS:20140624-094924798", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140624-094924798", "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": "10.1029/2000GL011404", "primary_object": { "basename": "grl13647.pdf", "url": "https://authors.library.caltech.edu/records/zmy0k-kpb71/files/grl13647.pdf" }, "resource_type": "article", "pub_year": "2000", "author_list": "Fahey, D. W.; Gao, R. S.; et el." }, { "id": "https://authors.library.caltech.edu/records/9gxtf-mq475", "eprint_id": 34109, "eprint_status": "archive", "datestamp": "2023-08-22 01:03:06", "lastmod": "2023-10-19 14:33:01", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Zhang-Hui", "name": { "family": "Zhang", "given": "Hui" } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Wu-Vincent-H", "name": { "family": "Wu", "given": "Vincent H." } }, { "id": "Blake-G-A", "name": { "family": "Blake", "given": "Geoffrey A." }, "orcid": "0000-0003-0787-1610" } ] }, "title": "Fractionation of ^(14)N^(15)N^(16)O and ^(15)N^(14)N^(16)O during photolysis at 213 nm", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2000 American Geophysical Union. \n\nReceived 14 November 1999; accepted 29 February 2000. \n\nWe would like to thank the NSF MRI program for the photolysis laser, CASIX Inc. for the BBO crystals and the Dreyfus Foundation for the FTIR spectrometer used in this study. Vincent Wu acknowledges financial support from an anonymous donor through a Caltech Summer Undergraduate Research Fellowship.\n\nPublished - 1999GL011236.pdf
", "abstract": "Motivated by Yung and Miller's [1997] suggestion that N2O is isotopically fractionated during UV photolysis in the stratosphere, we have studied the photolysis rates of the ^(14)N^(15)N^(16)O and ^(15)N^(14)N^(16)O structural isotopomers. In this study, we follow the concentrations of these compounds with FTIR spectroscopy during photolysis at 213 nm. When fitted to a Rayleigh fractionation model, the observations yield single\u2010stage enrichment factors of \u03f5(^(14)N^(15)N^(16)O / ^(14)N^(14)N^(16)O) = \u221273 \u00b1 5 per mil and \u03f5(^(15)N^(14)N^(16)O / ^(14)N^(14)N^(16)O) = \u221241 \u00b1 10 per mil. As predicted by Yung and Miller [1997], the photolysis rate of ^(15)N^(14)N^(16)O is faster than ^(14)N^(15)N^(16)O at this wavelength. The magnitude of the observed fractionation, however, is significantly larger than predicted.", "date": "2000-08-15", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "27", "number": "16", "publisher": "American Geophysical Union", "pagerange": "2481-2484", "id_number": "CaltechAUTHORS:20120914-144208949", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20120914-144208949", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Caltech Summer Undergraduate Research Fellowship (SURF)" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/1999GL011236", "primary_object": { "basename": "1999GL011236.pdf", "url": "https://authors.library.caltech.edu/records/9gxtf-mq475/files/1999GL011236.pdf" }, "resource_type": "article", "pub_year": "2000", "author_list": "Zhang, Hui; Wennberg, Paul O.; et el." }, { "id": "https://authors.library.caltech.edu/records/xgeg7-45554", "eprint_id": 46496, "eprint_status": "archive", "datestamp": "2023-08-22 01:01:13", "lastmod": "2023-10-26 19:47:22", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Zhang-Hui", "name": { "family": "Zhang", "given": "Hui" } }, { "id": "Roehl-C-M", "name": { "family": "Roehl", "given": "Coleen M." }, "orcid": "0000-0001-5383-8462" }, { "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" } ] }, "title": "Intensity of the second and third OH overtones of H_2O_2, HNO_3, and HO_2NO_2", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2000 American Geophysical Union. \n\nReceived November 23, 1999; revised February 9, 2000; accepted February 11, 2000. \n\nPaper number 2000JD900118. \n\nThis work is partly supported by NASA grant SA98-0055. We thank R.J. Salawitch for help on the HO_2NO_2 photolysis rate calculations. Useful communications with D. J. Donaldson are greatly appreciated.\n\nPublished - jgrd7492.pdf
", "abstract": "The 3\u03bd_(OH) and 4\u03bd_(OH) of H_2O_2, HNO_3, and HO_2NO_2 have been observed. The band strengths of 3\u03bd_(OH) are (7.0\u00b11.8) \u00d7 10^(\u221220), (2.9\u00b10.7) \u00d7 10^(\u221220), and (3.8\u00b11.1) \u00d7 10^(\u221220) cm^2 molecules^(\u22121) cm^(\u22121) for H_2O_2, HNO_3, and HO_2NO_2, respectively. Those of 4\u03bd_(OH) are (4.5\u00b1 .6) \u00d7 10^(\u221221), (2.8\u00b1 .0) \u00d7 10^(\u221221), and (3.0\u00b11.8) \u00d7 10^(\u221221) cm^2 molecules^(\u22121) cm^(\u22121) for H_2O_2, HNO_3, and HO_2NO_2, respectively. The uncertainty is for one standard deviation. Assuming excitation of these modes by solar absorption is dissociative for HO_2NO_2, these measurements confirm that this process will play a small role in the atmospheric photochemistry of the lower stratosphere.", "date": "2000-06-16", "date_type": "published", "publication": "Journal of Geophysical Research D", "volume": "105", "number": "D11", "publisher": "American Geophysical Union", "pagerange": "14593-14598", "id_number": "CaltechAUTHORS:20140625-075632457", "issn": "0148-0227", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140625-075632457", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "SA98-0055" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/2000JD900118", "primary_object": { "basename": "jgrd7492.pdf", "url": "https://authors.library.caltech.edu/records/xgeg7-45554/files/jgrd7492.pdf" }, "resource_type": "article", "pub_year": "2000", "author_list": "Zhang, Hui; Roehl, Coleen M.; et el." }, { "id": "https://authors.library.caltech.edu/records/crk24-j7450", "eprint_id": 46624, "eprint_status": "archive", "datestamp": "2023-08-22 14:09:56", "lastmod": "2023-10-26 19:53:12", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Del-Negro-L-A", "name": { "family": "Del Negro", "given": "L. A." } }, { "id": "Fahey-D-W", "name": { "family": "Fahey", "given": "D. W." } }, { "id": "Gao-R-S", "name": { "family": "Gao", "given": "R. S." } }, { "id": "Donnelly-S-G", "name": { "family": "Donnelly", "given": "S. G." } }, { "id": "Keim-E-R", "name": { "family": "Keim", "given": "E. R." } }, { "id": "Neuman-J-A", "name": { "family": "Neuman", "given": "J. A." } }, { "id": "Cohen-R-C", "name": { "family": "Cohen", "given": "R. C." }, "orcid": "0000-0001-6617-7691" }, { "id": "Perkins-K-K", "name": { "family": "Perkins", "given": "K. K." } }, { "id": "Koch-L-C", "name": { "family": "Koch", "given": "L. C." } }, { "id": "Salawitch-R-J", "name": { "family": "Salawitch", "given": "R. J." } }, { "id": "Lloyd-S-A", "name": { "family": "Lloyd", "given": "S. A." } }, { "id": "Proffitt-M-H", "name": { "family": "Proffitt", "given": "M. H." } }, { "id": "Margitan-J-J", "name": { "family": "Margitan", "given": "J. J." } }, { "id": "Stimpfle-R-M", "name": { "family": "Stimpfle", "given": "R. M." } }, { "id": "Bonne-G-P", "name": { "family": "Bonne", "given": "G. P." } }, { "id": "Voss-P-B", "name": { "family": "Voss", "given": "P. B." } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" }, { "id": "McElroy-C-T", "name": { "family": "McElroy", "given": "C. T." } }, { "id": "Swartz-W-H", "name": { "family": "Swartz", "given": "W. H." } }, { "id": "Kusterer-T-L", "name": { "family": "Kusterer", "given": "T. L." } }, { "id": "Anderson-D-E", "name": { "family": "Anderson", "given": "D. E." }, "orcid": "0000-0002-8310-0554" }, { "id": "Lait-L-R", "name": { "family": "Lait", "given": "L. R." } }, { "id": "Bui-T-P", "name": { "family": "Bui", "given": "T. P." } } ] }, "title": "Comparison of modeled and observed values of NO_2 and JNO_2 during the Photochemistry of Ozone Loss in the Arctic Region in Summer (POLARIS) mission", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1999 American Geophysical Union. \n\nManuscript Accepted: 13 April 1999; Manuscript Received: 4 December 1998. \n\nhe authors gratefully acknowledge T. F. Hanisco and E. J. Lanzendorf for use of the HO_(x) data set, J. C. Wilson and C. A. Brock for use of the aerosol data set, and P. A. Newman for the calculation of the solar exposure parameter. This work was supported by the NASA Upper Atmosphere Research Program, Atmospheric Chemistry and Modeling and Analysis Program, and the Atmospheric Effects of Stratospheric Aircraft Project of the NASA High Speed Research Program.\n\nPublished - jgrd6659.pdf
", "abstract": "Stratospheric measurements of NO, NO_(2), O_(3), ClO, and HO_(2) were made during spring, early summer, and late summer in the Arctic region during 1997 as part of the Photochemistry of Ozone Loss in the Arctic Region in Summer (POLARIS) field campaign. In the sunlit atmosphere, NO_(2) and NO are in steady state through NO2 photolysis and reactions involving O_(3), ClO, BrO, and HO_(2). By combining observations of O_(3), ClO, and HO_(2), observed and modeled values of the NO_(2) photolysis rate coefficient (JNO_(2)), and model estimates of BrO, several comparisons are made between steady state and measured values of both NO_(2) and JNO_(2). An apparent seasonal dependence in discrepancies between calculated and measured values was found; however, a source for this dependence could not be identified. Overall, the mean linear fits in the various comparisons show agreement within 19%, well within the combined uncertainties (\u00b150 to 70%). These results suggest that photochemistry controlling the NO_(2)/NO abundance ratio is well represented throughout much of the sunlit lower stratosphere. A reduction in the uncertainty of laboratory determinations of the rate coefficient of NO + O_(3) \u2192 NO_(2) + O_(2) would aid future analyses of these or similar atmospheric observations.", "date": "1999-11-20", "date_type": "published", "publication": "Journal of Geophysical Research D", "volume": "104", "number": "D21", "publisher": "American Geophysical Union", "pagerange": "26687-26703", "id_number": "CaltechAUTHORS:20140702-093844303", "issn": "0148-0227", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140702-093844303", "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": "10.1029/1999JD900246", "primary_object": { "basename": "jgrd6659.pdf", "url": "https://authors.library.caltech.edu/records/crk24-j7450/files/jgrd6659.pdf" }, "resource_type": "article", "pub_year": "1999", "author_list": "Del Negro, L. A.; Fahey, D. W.; et el." }, { "id": "https://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.edu/records/zr617-b1a46", "eprint_id": 47256, "eprint_status": "archive", "datestamp": "2023-08-22 13:47:18", "lastmod": "2023-10-26 20:26:45", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Salawitch-R-J", "name": { "family": "Salawitch", "given": "R. J." } }, { "id": "Donaldson-D-J", "name": { "family": "Donaldson", "given": "D. J." } }, { "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": "Perkins-K-K", "name": { "family": "Perkins", "given": "K. K." } }, { "id": "Lloyd-S-A", "name": { "family": "Lloyd", "given": "S. A." } }, { "id": "Vaida-V", "name": { "family": "Vaida", "given": "V." } }, { "id": "Gao-R-S", "name": { "family": "Gao", "given": "R. S." } }, { "id": "Hintsa-E-J", "name": { "family": "Hintsa", "given": "E. J." } }, { "id": "Cohen-R-C", "name": { "family": "Cohen", "given": "R. C." }, "orcid": "0000-0001-6617-7691" }, { "id": "Swartz-W-H", "name": { "family": "Swartz", "given": "W. H." } }, { "id": "Kusterer-T-L", "name": { "family": "Kusterer", "given": "T. L." } }, { "id": "Anderson-D-E", "name": { "family": "Anderson", "given": "D. E." }, "orcid": "0000-0002-8310-0554" } ] }, "title": "Twilight observations suggest unknown sources of HO_x", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1999 American Geophysical Union. \n\nReceived December 21, 1998; revised March 12; accepted March 24, 1999. \n\nPaper number 1999GL900255. \n\nWe thank NASA's Upper Atmosphere Research and the Atmospheric Effects of Aviation Programs for supporting the POLARIS field campaign (M. Kurylo, P. DeCola, and R. Kawa, project managers). POW acknowledges additional support from the NSF (ACM-9612282) for this work. DJD acknowledges NSERC for partial support of this work. VV acknowledges NSF for support. We thank C. Webster (for CH_(4) and CO), R. May (for H_(2)O), J. Margitan and M. Proffitt (for O_(3)), C. Wilson and C. Brock (for aerosol surface area), J. Elkins and E. Atlas (for organic halogens), L. Thomason (for aerosol extinction), R. McPeters (O_3 column and reflectivity), and M. Mlynczak and B. T. Marshall(for O_(2)(b^(1)\u03a3_(g))). We appreciate the leadership of D. Fahey and P. Newman, POLARIS lead scientists. We thank A. Tuck for motivating this study. A portion of this work was performed at JPL under contract from NASA.\n\nPublished - grl13064.pdf
", "abstract": "Measurements of the concentrations of OH and HO_(2) (HO_(x)) in the high-latitude lower stratosphere imply the existence of unknown photolytic sources of HO_(x). The strength of the additional HO_(x) source required to match the observations depends only weakly on solar zenith angle (SZA) for 80\u00b0 < SZA < 93\u00b0. The wavelengths responsible for producing this HO_(x) must be longer than 650 nm because the flux at shorter wavelengths is significantly attenuated at high SZA by scattering and absorption. Provided that the sources involve only a single photon, the strength of the bonds being broken must be < 45 kcal mole^(\u22121). We speculate that peroxynitric acid (HNO_4) dissociates after excitation to an unknown excited state with an integrated band cross section of 2-3 \u00d7 10^(\u221220) cm^(2) molecule^(\u22121) nm (650 < \u03bb < 1250 nm).", "date": "1999-05-15", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "26", "number": "10", "publisher": "American Geophysical Union", "pagerange": "1373-1376", "id_number": "CaltechAUTHORS:20140716-085906258", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140716-085906258", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA/JPL" }, { "agency": "NSF", "grant_number": "ACM-9612282" }, { "agency": "Natural Sciences and Engineering Research Council of Canada (NSERC)" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/1999GL900255", "primary_object": { "basename": "grl13064.pdf", "url": "https://authors.library.caltech.edu/records/zr617-b1a46/files/grl13064.pdf" }, "resource_type": "article", "pub_year": "1999", "author_list": "Wennberg, P. O.; Salawitch, R. J.; et el." }, { "id": "https://authors.library.caltech.edu/records/1ex4h-cvp13", "eprint_id": 47317, "eprint_status": "archive", "datestamp": "2023-08-22 13:43:19", "lastmod": "2023-10-26 20:29:58", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Gao-R-S", "name": { "family": "Gao", "given": "R. S." } }, { "id": "Fahey-D-W", "name": { "family": "Fahey", "given": "D. W." } }, { "id": "Del-Negro-L-A", "name": { "family": "Del Negro", "given": "L. A." } }, { "id": "Donnelly-S-G", "name": { "family": "Donnelly", "given": "S. G." } }, { "id": "Keim-E-R", "name": { "family": "Keim", "given": "E. R." } }, { "id": "Neuman-J-A", "name": { "family": "Neuman", "given": "J. A." } }, { "id": "Teverovskaia-E", "name": { "family": "Teverovskaia", "given": "E." } }, { "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": "Proffitt-M-H", "name": { "family": "Proffitt", "given": "M. H." } }, { "id": "Margitan-J-J", "name": { "family": "Margitan", "given": "J. J." } }, { "id": "Wilson-J-C", "name": { "family": "Wilson", "given": "J. C." } }, { "id": "Elkins-J-W", "name": { "family": "Elkins", "given": "J. W." } }, { "id": "Stimpfle-R-M", "name": { "family": "Stimpfle", "given": "R. M." } }, { "id": "Cohen-R-C", "name": { "family": "Cohen", "given": "R. C." }, "orcid": "0000-0001-6617-7691" }, { "id": "McElroy-C-T", "name": { "family": "McElroy", "given": "C. T." } }, { "id": "Bui-T-P", "name": { "family": "Bui", "given": "T. P." } }, { "id": "Salawitch-R-J", "name": { "family": "Salawitch", "given": "R. J." } }, { "id": "Brown-S-S", "name": { "family": "Brown", "given": "S. S." } }, { "id": "Ravishankara-A-R", "name": { "family": "Ravishankara", "given": "A. R." } }, { "id": "Portmann-R-W", "name": { "family": "Portmann", "given": "R. W." } }, { "id": "Ko-M-K-W", "name": { "family": "Ko", "given": "M. K. W." } }, { "id": "Weisenstein-D-K", "name": { "family": "Weisenstein", "given": "D. K." } }, { "id": "Newman-P-A", "name": { "family": "Newman", "given": "P. A." } } ] }, "title": "A comparison of observations and model simulations of NO_x/NO_y in the lower stratosphere", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1999 American Geophysical Union. \n\nReceived November2 4, 1998; revised February 18, 1999; accepted February 22, 1999. Paper number 1999GL900162. \n\nWe thank the pilots and ground crew of the NASA ER-2 aircraft. This work is supported by the NASA Upper Atmospheric Research Program and the Atmospheric Effects of Aviation Project.\n\nPublished - grl12971.pdf
", "abstract": "Extensive airborne measurements of the reactive nitrogen reservoir (NO_(y)) and its component nitric oxide (NO) have been made in the lower stratosphere. Box model simulations that are constrained by observations of radical and long-lived species and which include heterogeneous chemistry systematically underpredict the NO_x (= NO + NO_2) to NO_y ratio. The model agreement is substantially improved if newly measured rate coefficients for the OH + NO_2 and OH + HNO_3 reactions are used. When included in 2-D models, the new rate coefficients significantly increase the calculated ozone loss due to NO_x and modestly change the calculated ozone abundances in the lower stratosphere. Ozone changes associated with the emissions of a fleet of supersonic aircraft are also altered.", "date": "1999-04-15", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "26", "number": "8", "publisher": "American Geophysical Union", "pagerange": "1153-1156", "id_number": "CaltechAUTHORS:20140718-090035893", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140718-090035893", "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": "10.1029/1999GL900162", "primary_object": { "basename": "grl12971.pdf", "url": "https://authors.library.caltech.edu/records/1ex4h-cvp13/files/grl12971.pdf" }, "resource_type": "article", "pub_year": "1999", "author_list": "Gao, R. S.; Fahey, D. W.; et el." }, { "id": "https://authors.library.caltech.edu/records/2288w-04416", "eprint_id": 58061, "eprint_status": "archive", "datestamp": "2023-08-22 13:31:18", "lastmod": "2023-10-23 18:03:01", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul" }, "orcid": "0000-0002-6126-3854" } ] }, "title": "Atmospheric chemistry: Bromine explosion", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 1999 Macmillan Magazines Ltd.", "abstract": "Bromine free radicals are emerging as important players in the photochemistry of the lower atmosphere, at least on local scales. Earlier this month, Hebestreit et al. described the discovery of air laden with bromine monoxide (BrO) wafting off the salt pans near the Dead Sea. And on page 338 of this issue, McElroy and colleagues report observations of BrO, obtained by remote measurements in the Arctic, that suggest bromine is present between the tropopause (at about 8 km height) and the top of the planetary boundary layer (~1 km). The planetary boundary layer is unlike the free troposphere that lies above it because the turbulence mixing timescale is very fast, and so exchange of gases with the surface occurs quickly (less than 1 day).", "date": "1999-01-28", "date_type": "published", "publication": "Nature", "volume": "397", "number": "6717", "publisher": "Nature Publishing Group", "pagerange": "299-301", "id_number": "CaltechAUTHORS:20150605-142337991", "issn": "0028-0836", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150605-142337991", "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": "10.1038/16805", "resource_type": "article", "pub_year": "1999", "author_list": "Wennberg, Paul" }, { "id": "https://authors.library.caltech.edu/records/4rb4v-g8m57", "eprint_id": 46577, "eprint_status": "archive", "datestamp": "2023-08-22 12:34:17", "lastmod": "2023-10-26 19:51:03", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "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": "Jaegl\u00e9-L", "name": { "family": "Jaegl\u00e9", "given": "L." } }, { "id": "Jacob-D-J", "name": { "family": "Jacob", "given": "D. J." }, "orcid": "0000-0002-6373-3100" }, { "id": "Hintsa-E-J", "name": { "family": "Hintsa", "given": "E. J." } }, { "id": "Lanzendorf-E-J", "name": { "family": "Lanzendorf", "given": "E. J." } }, { "id": "Anderson-J-G", "name": { "family": "Anderson", "given": "J. G." } }, { "id": "Gao-R-S", "name": { "family": "Gao", "given": "R.-S." } }, { "id": "Keim-E-R", "name": { "family": "Keim", "given": "E. R." } }, { "id": "Donnelly-S-G", "name": { "family": "Donnelly", "given": "S. G." } }, { "id": "Del-Negro-L-A", "name": { "family": "Del Negro", "given": "L. A." } }, { "id": "Fahey-D-W", "name": { "family": "Fahey", "given": "D. W." } }, { "id": "McKeen-S-A", "name": { "family": "McKeen", "given": "S. A." } }, { "id": "Salawitch-R-J", "name": { "family": "Salawitch", "given": "R. J." } }, { "id": "Webster-C-R", "name": { "family": "Webster", "given": "C. R." } }, { "id": "May-R-D", "name": { "family": "May", "given": "R. D." } }, { "id": "Herman-R-L", "name": { "family": "Herman", "given": "R. L." } }, { "id": "Proffitt-M-H", "name": { "family": "Proffitt", "given": "M. H." } }, { "id": "Margitan-J-J", "name": { "family": "Margitan", "given": "J. J." } }, { "id": "Atlas-E-L", "name": { "family": "Atlas", "given": "E. L." }, "orcid": "0000-0003-3847-5346" }, { "id": "Schauffler-S-M", "name": { "family": "Schauffler", "given": "S. M." } }, { "id": "Flocke-F-M", "name": { "family": "Flocke", "given": "F." } }, { "id": "McElroy-C-T", "name": { "family": "McElroy", "given": "C. T." } }, { "id": "Bui-T-P", "name": { "family": "Bui", "given": "T. P." } } ] }, "title": "Hydrogen Radicals, Nitrogen Radicals, and the Production of O_3 in the Upper Troposphere", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 1998 American Association for the Advancement of Science. \n\nReceived 15 October 1997; accepted 18 November 1997. \n\nWe thank the pilots and ground crew of the NASA ER-2 Aircraft, and the STRAT mission scientists (S. Wofsy, Harvard University, and P. Newman, NASA Goddard Space Flight Center) for their help obtaining this data set. K. Wolfe, J. Barrilleaux, E. Condon, S. Hipskind, M. Craig, S. Gaines, J. Goosby, and O. Allison provided logistical support for this field effort. We acknowledge R. Lueb, V. Stroud, and H. Krapfl for assistance with the whole-air sampler data set. A portion of the research described in this paper was carried out by the Jet Propulsion Laboratory, California Institute of Technology, under contract with NASA. Partial support for analysis of the STRAT data set was provided by a grant from the National Science Foundation (ATM 9612282). The STRAT program was supported by NASA through the Upper Atmosphere Research Program, the Atmospheric Chemistry Modeling and Analysis Program, and by the Atmospheric Effects of Aviation Project. We thank the officers of these programs, M. Kurylo, H. Wesoky, J. Kaye, R. Friedl, R. Kawa, D. Peterson, and P. DeCola, for support.", "abstract": "The concentrations of the hydrogen radicals OH and HO2in the middle and upper troposphere were measured simultaneously with those of NO, O_3, CO, H_(2)O, CH_4, non-methane hydrocarbons, and with the ultraviolet and visible radiation field. The data allow a direct examination of the processes that produce O_3 in this region of the atmosphere. Comparison of the measured concentrations of OH and HO_2 with calculations based on their production from water vapor, ozone, and methane demonstrate that these sources are insufficient to explain the observed radical concentrations in the upper troposphere. The photolysis of carbonyl and peroxide compounds transported to this region from the lower troposphere may provide the source of HO_x required to sustain the measured abundances of these radical species. The mechanism by which NO affects the production of O_3 is also illustrated by the measurements. In the upper tropospheric air masses sampled, the production rate for ozone (determined from the measured concentrations of HO_2 and NO) is calculated to be about 1 part per billion by volume each day. This production rate is faster than previously thought and implies that anthropogenic activities that add NO to the upper troposphere, such as biomass burning and aviation, will lead to production of more O_3 than expected.", "date": "1998-01-02", "date_type": "published", "publication": "Science", "volume": "279", "number": "5347", "publisher": "American Association for the Advancement of Science", "pagerange": "49-53", "id_number": "CaltechAUTHORS:20140630-134403656", "issn": "0036-8075", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140630-134403656", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "ATM-9612282" }, { "agency": "NASA" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1126/science.279.5347.49", "resource_type": "article", "pub_year": "1998", "author_list": "Wennberg, P. O.; Hanisco, T. F.; et el." }, { "id": "https://authors.library.caltech.edu/records/pkfd1-30p47", "eprint_id": 46599, "eprint_status": "archive", "datestamp": "2023-08-22 12:23:41", "lastmod": "2023-10-26 19:52:00", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Folkins-I", "name": { "family": "Folkins", "given": "Ian" } }, { "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": "Anderson-J-G", "name": { "family": "Anderson", "given": "J. G." } }, { "id": "Salawitch-R-J", "name": { "family": "Salawitch", "given": "R. J." } } ] }, "title": "OH, HO_2, NO in two biomass burning plumes: Sources of HO_x and implications for ozone production", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1997 American Geophysical Union. \n\nManuscript Accepted: 17 October 1997; Manuscript Received: 31 May 1997. \n\nWe acknowledge the assistance of John Neima, helpful comments from A. J. Weinheimer, and financial support from the Atmospheric Environment Service and Natural Sciences and Engineering Council of Canada. We thank the ER-2 pilots and ground crew, and the ASHOE/MAESA investigators for the use of their data. The mission scientists for this campaign were Bill Brune and Adrian Tuck. ASHOE/MAESA was supported by NASA through the Upper Atmosphere Research Program, the Atmospheric Effects of Aviation Project, and the Atmospheric Chemistry Modeling and Analysis Program. Additional support for ASHOE/MAESA came from base funding by NOAA.\n\nPublished - grl10569.pdf
", "abstract": "The ER-2 made two descents through upper tropospheric biomass burning plumes during ASHOE/MAESA. HO_x (= OH + HO_2) concentrations are largely self-limited outside the plumes, but become progressively more limited by reactions with NO_x (= NO + NO_2) at the higher NO_x concentrations inside the plumes. Sources of HO_x in addition to H_(2)O and CH_4 oxidation are required to balance the known HOx sinks both in the plumes and in the background upper troposphere. HO_x concentrations were consistently underestimated by a model constrained by observed NO_x concentrations. The size of the model underestimate is reduced when acetone photolysis is included. Models which do not include the additional HO_x sources required to balance the HO_x budget are likely to underestimate ozone production rates.", "date": "1997-12-15", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "24", "number": "24", "publisher": "American Geophysical Union", "pagerange": "3185-3188", "id_number": "CaltechAUTHORS:20140701-103400492", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140701-103400492", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Atmospheric Environment Service" }, { "agency": "Natural Sciences and Engineering Research Council of Canada (NSERC)" }, { "agency": "NASA" }, { "agency": "National Oceanic and Atmospheric Administration (NOAA)" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/97GL03047", "primary_object": { "basename": "grl10569.pdf", "url": "https://authors.library.caltech.edu/records/pkfd1-30p47/files/grl10569.pdf" }, "resource_type": "article", "pub_year": "1997", "author_list": "Folkins, Ian; Wennberg, P. O.; et el." }, { "id": "https://authors.library.caltech.edu/records/h81vm-5vk15", "eprint_id": 47259, "eprint_status": "archive", "datestamp": "2023-08-22 12:23:51", "lastmod": "2023-10-26 20:26:52", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Jaegl\u00e9-L", "name": { "family": "Jaegl\u00e9", "given": "L." } }, { "id": "Jacob-D-J", "name": { "family": "Jacob", "given": "D. J." }, "orcid": "0000-0002-6373-3100" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Spivakovsky-C-M", "name": { "family": "Spivakovsky", "given": "C. M." } }, { "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": "Hintsa-E-J", "name": { "family": "Hintsa", "given": "E. J." } }, { "id": "Fahey-D-W", "name": { "family": "Fahey", "given": "D. W." } }, { "id": "Keim-E-R", "name": { "family": "Keim", "given": "E. R." } }, { "id": "Proffitt-M-H", "name": { "family": "Proffitt", "given": "M. H." } }, { "id": "Atlas-E-L", "name": { "family": "Atlas", "given": "E. L." }, "orcid": "0000-0003-3847-5346" }, { "id": "Flocke-F-M", "name": { "family": "Flocke", "given": "F." } }, { "id": "Schauffler-S", "name": { "family": "Schauffler", "given": "S." } }, { "id": "McElroy-C-T", "name": { "family": "McElroy", "given": "C. T." } }, { "id": "Midwinter-C", "name": { "family": "Midwinter", "given": "C." } }, { "id": "Pfister-L", "name": { "family": "Pfister", "given": "L." } }, { "id": "Wilson-J-C", "name": { "family": "Wilson", "given": "J. C." } } ] }, "title": "Observed OH and HO_2 in the upper troposphere suggest a major source from convective injection of peroxides", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1997 American Geophysical Union.\n\nReceived June 30, 1997; accepted September 16, 1997.\n\nPaper number 97GL03004.\n\nThis work was supported by the National Aeronautics and Space Administration (NASA-NAG5-2688; NASA-NAG2-1100) and the National Science Foundation (NSF-ATM-9612282). We thank the ground crew and pilots of the ER-2 for their efforts in obtaining the data set. STRAT was sponsored by NASA's Upper Atmosphere Research Program, the Atmospheric Effects of Aviation Project, and the Atmospheric Chemistry Modeling and Analysis Program. The project scientists for STRAT were Paul Newman, NASA Goddard, and Steven Wofsy, Harvard University.\n\nPublished - grl10556.pdf
", "abstract": "ER-2 aircraft observations of OH and HO_2 concentrations in the upper troposphere during the NASA/STRAT campaign are interpreted using a photochemical model constrained by local observations of O_3, H_2O, NO, CO, hydrocarbons, albedo and overhead ozone column. We find that the reaction Q(^(1)D) + H_2O is minor compared to acetone photolysis as a primary source of HO_x (= OH + peroxy radicals) in the upper troposphere. Calculations using a diel steady state model agree with observed HO_x concentrations in the lower stratosphere and, for some flights, in the upper troposphere. However, for other flights in the upper troposphere, the steady state model underestimates observations by a factor of 2 or more. These model underestimates are found to be related to a recent (< 1 week) convective origin of the air. By conducting time-dependent model calculations along air trajectories determined for the STRAT flights, we show that convective injection of CH_3OOH and H_2O_2 from the boundary layer to the upper troposphere could resolve the discrepancy. These injections of HO_x reservoirs cause large HO_x increases in the tropical upper troposphere for over a week downwind of the convective activity. We propose that this mechanism provides a major source of HO_x in the upper troposphere. Simultaneous measurements of peroxides, formaldehyde and acetone along with OH and HO_2 are needed to test our hypothesis.", "date": "1997-12-15", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "24", "number": "24", "publisher": "American Geophysical Union", "pagerange": "3181-3184", "id_number": "CaltechAUTHORS:20140716-092820107", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140716-092820107", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NAG5-2688" }, { "agency": "NASA", "grant_number": "NAG2-1100" }, { "agency": "NSF", "grant_number": "ATM-9612282" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/97GL03004", "primary_object": { "basename": "grl10556.pdf", "url": "https://authors.library.caltech.edu/records/h81vm-5vk15/files/grl10556.pdf" }, "resource_type": "article", "pub_year": "1997", "author_list": "Jaegl\u00e9, L.; Jacob, D. J.; et el." }, { "id": "https://authors.library.caltech.edu/records/qx2s6-fkh66", "eprint_id": 46625, "eprint_status": "archive", "datestamp": "2023-08-22 12:23:46", "lastmod": "2023-10-26 19:53:14", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "McKeen-S-A", "name": { "family": "McKeen", "given": "S. A." } }, { "id": "Gierczak-T", "name": { "family": "Gierczak", "given": "T." } }, { "id": "Burkholder-J-B", "name": { "family": "Burkholder", "given": "J. B." } }, { "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": "Keim-E-R", "name": { "family": "Keim", "given": "E. R." } }, { "id": "Gao-R-S", "name": { "family": "Gao", "given": "R.-S." } }, { "id": "Liu-S-C", "name": { "family": "Liu", "given": "S. C." } }, { "id": "Ravishankara-A-R", "name": { "family": "Ravishankara", "given": "A. R." } }, { "id": "Fahey-D-W", "name": { "family": "Fahey", "given": "D. W." } } ] }, "title": "The photochemistry of acetone in the upper troposphere: A source of odd-hydrogen radicals", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1997 American Geophysical Union.\n\nManuscript Accepted: 11 November 1997; Manuscript Received: 8 May 1997.\n\nThis research was supported in part by the Atmospheric Chemistry Project of the Climate and Global Change Program\nof NOAA, as well as the Upper Atmospheric Research and Atmospheric Effects of Aviation Projects within NASA. We are indebted to the pilots, crew and mission scientists of the STRAT campaign. They include E . Atlas, J. Margitan, M. H. Proffitt, E. Hintsa, T. E. McElroy, J. Wilson, C. R.\nWebster, R . D. May, R. Herman, and K. R. Chan. Discussions with Ross Salawitch, Lyatt Jaegl\u00e9, Daniel Jacobs, Robert Chatfield, Hanwant Singh, and Michael Trainer are also greatly appreciated.\n\nPublished - grl10647.pdf
", "abstract": "This paper summarizes measured photodissociation quantum yields for acetone in the 290-320 nm wavelength region for pressures and temperatures characteristic of the upper troposphere. Calculations combine this laboratory data with trace gas concentrations obtained during the NASA and NOAA sponsored Stratospheric Tracers of Atmospheric Transport (STRAT) field campaign, in which measurements of OH, HO_(2), odd-nitrogen, and other compounds were collected over Hawaii, and west of California during fall and winter of 1995/1996. OH and HO_(2) concentrations within 2 to 5 km layers just below the tropopause are \u223c50% larger than expected from O_(3), CH_(4), and H_(2)O chemistry alone. Although not measured during STRAT, acetone is inferred from CO measurements and acetone-CO correlations from a previous field study. These inferred acetone levels are a significant source of odd-hydrogen radicals that can explain a large part of the discrepancy in the upper troposphere. For lower altitudes, the inferred acetone makes a negligible contribution to HO_(x) (HO+HO_(2)), but influences NO_(y) partitioning. A major fraction of HO_(x) production by acetone is through CH_(2)O formation, and the HO_(x) discrepancy can also be explained by CH_(2)O levels in the 20 to 50 pptv range, regardless of the source.", "date": "1997-12-15", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "24", "number": "24", "publisher": "American Geophysical Union", "pagerange": "3177-3180", "id_number": "CaltechAUTHORS:20140702-094103692", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140702-094103692", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "National Oceanic and Atmospheric Administration (NOAA)" }, { "agency": "NASA" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/97GL03349", "primary_object": { "basename": "grl10647.pdf", "url": "https://authors.library.caltech.edu/records/qx2s6-fkh66/files/grl10647.pdf" }, "resource_type": "article", "pub_year": "1997", "author_list": "McKeen, S. A.; Gierczak, T.; et el." }, { "id": "https://authors.library.caltech.edu/records/jp087-1wh18", "eprint_id": 47343, "eprint_status": "archive", "datestamp": "2023-09-15 04:47:18", "lastmod": "2023-10-23 21:09:49", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Lanzendorf-E-J", "name": { "family": "Lanzendorf", "given": "E. J." } }, { "id": "Hanisco-T-F", "name": { "family": "Hanisco", "given": "T. F." }, "orcid": "0000-0001-9434-8507" }, { "id": "Donahue-N-M", "name": { "family": "Donahue", "given": "N. M." } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" } ] }, "title": "Comment on: \"The measurement of tropospheric OH radicals by laser-induced fluorescence spectroscopy during the POPCORN Field Campaign\" by Hofzumahaus et al. and \"Intercomparison of tropospheric OH radical measurements by multiple folded long-path laser absorption and laser induced fluorescence\" by Brauers et al.", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1997 American Geophysical Union. \n\nManuscript Accepted: 8 Oct 1997. Manuscript Received: 11 Mar 1997. \n\nPaper number 97GL02899.\n\nWe thank Dr. Kouichi Yoshino of the Harvard-Smithsonian Center for Astrophysics (H-SCfA) for use of the vacuum ultraviolets pectrometearn df or his expertise. The O_2 cross sections were obtained from the H-SCfA web site: http://cfawww.harvard.edu/amp/data/S-R.html. We thank NASA's Upper Atmospheric Research Program for support.\n\nPublished - grl10519.pdf
", "abstract": "Calibration of laser induced fluorescence (LIF) instruments\nthat measure OH is challenging because it is difficult to\nreliably introduce a known amount of this reactive radical into a measurement apparatus. In a recent paper, Hofzumahaus et al., [1996] describe a novel and seemingly simple technique to accomplish this goal: they dissociate trace quantities of water vapor in air with a low pressure mercury (Hg) lamp to produce low concentrations (10^5 - 10^9 cm^(-3)) of OH (R1).", "date": "1997-12-01", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "24", "number": "23", "publisher": "American Geophysical Union", "pagerange": "3037-3038", "id_number": "CaltechAUTHORS:20140718-143321101", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140718-143321101", "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": "10.1029/97GL02899", "primary_object": { "basename": "grl10519.pdf", "url": "https://authors.library.caltech.edu/records/jp087-1wh18/files/grl10519.pdf" }, "resource_type": "article", "pub_year": "1997", "author_list": "Lanzendorf, E. J.; Hanisco, T. F.; et el." }, { "id": "https://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.edu/records/f9mpg-xaa34", "eprint_id": 46504, "eprint_status": "archive", "datestamp": "2023-08-22 11:38:48", "lastmod": "2023-10-26 19:47:53", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Brault-J-W", "name": { "family": "Brault", "given": "J. W." } }, { "id": "Hanisco-T-F", "name": { "family": "Hanisco", "given": "T. F." }, "orcid": "0000-0001-9434-8507" }, { "id": "Salawitch-R-J", "name": { "family": "Salawitch", "given": "R. J." } }, { "id": "Mount-G-H", "name": { "family": "Mount", "given": "George H." } } ] }, "title": "The atmospheric column abundance of IO: Implications for stratospheric ozone", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1997 American Geophysical Union. \n\nReceived January 3, 1996; revised November 17, 1996; accepted November 18, 1996. \n\nPaper number 96JD03712. \n\nWe would like to thank the many individuals and programs that contributed to this work. At Harvard, support for the purchase of the Bruker FTS was provided through grants from the National Science Foundation (ATM-8921312) and the Empire State Electric Energy Research Corporation. Support for P.O.W. and T.F.H. was provided by the National Aeronautical and Space Administration (NASA) Upper Atmosphere Research Program (NAG-1-1305). At Kitt Peak we would like to thank the National Solar Observatory for use of the McMath-Pierce telescope and the solar spectrometer. Research by R.J.S. at the Jet Propulsion Laboratory, California Institute of Technology, was performed under contract with NASA. Paul Newman from NASA Goddard kindly provided information on the tropopauseh eight above Kitt Peak. We thank M.J. Kurylo, A. R. Ravishankara, and J .-P. Pommereau for sharing information from their laboratories on the kinetics and photochemistry of iodine prior to publication. Finally, we would also like to thank Kathy Perkins, Kelly Chance, Stan Sander, and Susan Solomon for their comments on the manuscript.\n\nPublished - jgrd4836.pdf
", "abstract": "Absorption attributable to atmospheric IO is observed in high-resolution, high air mass solar spectra taken at the National Solar Observatory, Kitt Peak, Arizona, in March 1995. These observations, together with cross sections measured in the laboratory for the IO {A^(2)\u03a03/2\u2190X^(2)\u03a0_(3/2) (2,0)} rotationally resolved electronic transition, are consistent with a total stratospheric iodine mixing ratio of 0.2 (+0.3 \u22120.2) parts per trillion by volume. This result, combined with recent laboratory measurements of the rate of the reactions of IO with other halogen species, suggests that iodine chemistry is not responsible for the reductions observed in lower stratospheric ozone during the last several decades.", "date": "1997-04-20", "date_type": "published", "publication": "Journal of Geophysical Research D", "volume": "102", "number": "D7", "publisher": "American Geophysical Union", "pagerange": "8887-8898", "id_number": "CaltechAUTHORS:20140625-112244759", "issn": "0148-0227", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140625-112244759", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "ATM-8921312" }, { "agency": "Empire State Electric Energy Research Corporation" }, { "agency": "NASA", "grant_number": "NAG-1-1305" }, { "agency": "NASA/JPL/Caltech" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/96JD03712", "primary_object": { "basename": "jgrd4836.pdf", "url": "https://authors.library.caltech.edu/records/f9mpg-xaa34/files/jgrd4836.pdf" }, "resource_type": "article", "pub_year": "1997", "author_list": "Wennberg, P. O.; Brault, J. W.; et el." }, { "id": "https://authors.library.caltech.edu/records/qc878-1bz70", "eprint_id": 46623, "eprint_status": "archive", "datestamp": "2023-08-22 11:31:54", "lastmod": "2023-10-26 19:53:10", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Hanisco-T-F", "name": { "family": "Hanisco", "given": "T. F." }, "orcid": "0000-0001-9434-8507" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Cohen-R-C", "name": { "family": "Cohen", "given": "R. C." }, "orcid": "0000-0001-6617-7691" }, { "id": "Anderson-J-G", "name": { "family": "Anderson", "given": "J. G." } }, { "id": "Fahey-D-W", "name": { "family": "Fahey", "given": "D. W." } }, { "id": "Keim-E-R", "name": { "family": "Keim", "given": "E. R." } }, { "id": "Gao-R-S", "name": { "family": "Gao", "given": "R. S." } }, { "id": "Wamsley-R-C", "name": { "family": "Wamsley", "given": "R. C." } }, { "id": "Donnelly-S-G", "name": { "family": "Donnelly", "given": "S. G." } }, { "id": "Del-Negro-L-A", "name": { "family": "Del Negro", "given": "L. A." } }, { "id": "Salawitch-R-J", "name": { "family": "Salawitch", "given": "R. J." } }, { "id": "Kelly-K-K", "name": { "family": "Kelly", "given": "K. K." } }, { "id": "Proffitt-M-H", "name": { "family": "Proffitt", "given": "M. H." } } ] }, "title": "The role of HO_x in super- and subsonic aircraft exhaust plumes", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1997 American Geophysical Union. \n\nReceived September 26, 1996; revised November 21, 1996; accepted November 25, 1996. \n\nThe authors thank the pilots of the NASA ER-2 and of the Air France Concorde for their achievements. We also acknowledge support from NASA's Upper Atmospheric Research and High Speed Research Programs.\n\nPublished - grl9862.pdf
", "abstract": "The generation of sulfuric acid aerosols in aircraft exhaust has emerged as a critical issue in determining the impact of supersonic aircraft on stratospheric ozone. It has long been held that the first step in the mechanism of aerosol formation is the oxidation of SO_(2) emitted from the engine by OH in the exhaust plume. We report in situ measurements of OH and HO_(2) in the exhaust plumes of a supersonic (Air France Concorde) and a subsonic (NASA ER-2) aircraft in the lower stratosphere. These measurements imply that reactions with OH are responsible for oxidizing only a small fraction of SO_(2) (2%), and thus cannot explain the large number of particles observed in the exhaust wake of the Concorde.", "date": "1997-01-01", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "24", "number": "1", "publisher": "American Geophysical Union", "pagerange": "65-68", "id_number": "CaltechAUTHORS:20140702-093146466", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140702-093146466", "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": "10.1029/96GL03724", "primary_object": { "basename": "grl9862.pdf", "url": "https://authors.library.caltech.edu/records/qc878-1bz70/files/grl9862.pdf" }, "resource_type": "article", "pub_year": "1997", "author_list": "Hanisco, T. F.; Wennberg, P. O.; et el." }, { "id": "https://authors.library.caltech.edu/records/hhag2-e1s06", "eprint_id": 47339, "eprint_status": "archive", "datestamp": "2023-08-22 11:20:04", "lastmod": "2023-10-26 20:30:51", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Dubey-M-K", "name": { "family": "Dubey", "given": "Manvendra K." } }, { "id": "Hanisco-T-F", "name": { "family": "Hanisco", "given": "Thomas F." }, "orcid": "0000-0001-9434-8507" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Anderson-J-G", "name": { "family": "Anderson", "given": "James G." } } ] }, "title": "Monitoring potential photochemical interference in laser-induced fluorescence measurements of atmospheric OH", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1996 American Geophysical Union. \n\nManuscript Accepted: 19 Sep 1996. Manuscript Received: 17 Jul 1996. Paper number 96GL03008. \n\nWe thank NASA's Upper Atmospheric Research and Atmospheric Effects of Aviation Programs for support.\n\nPublished - grl9704.pdf
", "abstract": "In situ laser-induced fluorescence measurements of atmospheric OH are susceptible to interference from laser generated OH, particularly in the troposphere. To quantify this interference we implement the addition of perfluoropropene, C_3F_6, for the chemical removal of OH from the ambient air. The removal rate of OH by C_3F_6 is determined in the laboratory using the discharge flow technique. Over the temperature range 249 to 296 K the rate constant is (6.0\u00b10.8) \u00d7 10^(\u221213) exp[(370\u00b140)/T] cm^\u00b3 molecule^(\u22121) s^(\u22121), independent of pressure. In situ measurements using C_3F_6 addition are performed in both aircraft-borne and ground-based experiments. These studies show that laser excitation of the ^\u00b2\u03a3^+(v=1)\u2190 ^\u00b2\u03a0(v=0) transition (282 nm) at high pulse repetition rates and low peak power can provide reliable and sensitive measurements of tropospheric OH.", "date": "1996-11-01", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "23", "number": "22", "publisher": "American Geophysical Union", "pagerange": "3215-3218", "id_number": "CaltechAUTHORS:20140718-140607725", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140718-140607725", "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": "10.1029/96GL03008", "primary_object": { "basename": "grl9704.pdf", "url": "https://authors.library.caltech.edu/records/hhag2-e1s06/files/grl9704.pdf" }, "resource_type": "article", "pub_year": "1996", "author_list": "Dubey, Manvendra K.; Hanisco, Thomas F.; et el." }, { "id": "https://authors.library.caltech.edu/records/0xkav-k7786", "eprint_id": 47330, "eprint_status": "archive", "datestamp": "2023-08-22 11:19:59", "lastmod": "2023-10-26 20:30:31", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Keim-E-R", "name": { "family": "Keim", "given": "E. R." } }, { "id": "Fahey-D-W", "name": { "family": "Fahey", "given": "D. W." } }, { "id": "Del-Negro-L-A", "name": { "family": "Del Negro", "given": "L. A." } }, { "id": "Woodbridge-E-L", "name": { "family": "Woodbridge", "given": "E. L." } }, { "id": "Gao-R-S", "name": { "family": "Gao", "given": "R. S." } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Cohen-R-C", "name": { "family": "Cohen", "given": "R. C." }, "orcid": "0000-0001-6617-7691" }, { "id": "Stimpfle-R-M", "name": { "family": "Stimpfle", "given": "R. M." } }, { "id": "Kelly-K-K", "name": { "family": "Kelly", "given": "K. K." } }, { "id": "Hintsa-E-J", "name": { "family": "Hintsa", "given": "E. J." } }, { "id": "Wilson-J-C", "name": { "family": "Wilson", "given": "J. C." } }, { "id": "Jonsson-H-H", "name": { "family": "Jonsson", "given": "H. H." }, "orcid": "0000-0003-3043-1074" }, { "id": "Dye-J-E", "name": { "family": "Dye", "given": "J. E." } }, { "id": "Baumgardner-D", "name": { "family": "Baumgardner", "given": "D." } }, { "id": "Kawa-S-R", "name": { "family": "Kawa", "given": "S. R." } }, { "id": "Salawitch-R-J", "name": { "family": "Salawitch", "given": "R. J." } }, { "id": "Proffitt-M-H", "name": { "family": "Proffitt", "given": "M. H." } }, { "id": "Loewenstein-M", "name": { "family": "Loewenstein", "given": "M." } }, { "id": "Podolske-J-R", "name": { "family": "Podolske", "given": "J. R." } }, { "id": "Chan-K-R", "name": { "family": "Chan", "given": "K. R." } } ] }, "title": "Observations of large reductions in the NO/NO_y ratio near the mid-latitude tropopause and the role of heterogeneous chemistry", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1996 American Geophysical Union.\n\nReceived June 10, 1996; revised August 14, 1996; accepted August 19, 1996.\n\nThis work is supported by the High-Speed Research Program and Upper Atmosphere Research Program of NASA. The authors appreciate discussions with H. S. Johnston. ERK acknowledges postdoctoral support from the National Research Council.\n\nPublished - grl9616.pdf
", "abstract": "During the 1993 NASA Stratospheric Photochemistry, Aerosols and Dynamics Expedition (SPADE), anomalously low nitric oxide (NO) was found in a distinct sunlit layer located above the mid-latitude tropopause. The presence of a significant amount of reactive nitrogen (NO_y) in the layer implies the systematic removal of NO, which is without precedent in stratospheric in situ observations. Large increases in measured chlorine monoxide (ClO) and the hydroperoxyl radical (HO_2) also were observed in the layer. Heterogeneous reaction rate constants of chlorine nitrate (ClONO_2) with hydrogen chloride (HCl) and H_2O to form nitric acid (HNO_3) on sulfate aerosol are enhanced in the NO removal layer by local increases in H_2O and aerosol surface area. The associated conversion of NO_x (= NO + NO_2) to HNO_3 is the most likely cause of the observed low NO and NO_x/NO_y values and high ClO values.", "date": "1996-11-01", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "23", "number": "22", "publisher": "American Geophysical Union", "pagerange": "3223-3226", "id_number": "CaltechAUTHORS:20140718-115240464", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140718-115240464", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA" }, { "agency": "National Research Council of Canada" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/96GL02593", "primary_object": { "basename": "grl9616.pdf", "url": "https://authors.library.caltech.edu/records/0xkav-k7786/files/grl9616.pdf" }, "resource_type": "article", "pub_year": "1996", "author_list": "Keim, E. R.; Fahey, D. W.; et el." }, { "id": "https://authors.library.caltech.edu/records/6xdp5-gca05", "eprint_id": 29344, "eprint_status": "archive", "datestamp": "2023-08-22 10:38:23", "lastmod": "2023-10-24 22:07:32", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "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": "Stimpfle-R-M", "name": { "family": "Stimpfle", "given": "R. M." } }, { "id": "Lapson-L-B", "name": { "family": "Lapson", "given": "L. B." } }, { "id": "Anderson-J-G", "name": { "family": "Anderson", "given": "J. G." } } ] }, "title": "In Situ Measurements of OH and HO_2 in the Upper Troposphere and Stratosphere", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1995 American Meteorological Society. \n\nManuscript received 4 October 1994, in final form 23 January 1995. \n\nWe thank the pilots and ground crew of the NASA ER-2 (NASA Ames Research Center, Moffett Field, California) as well as the support staff of the National Scientific Balloon Facility (Palestine, Texas). The ER-2 HO_x instrument was developed in part by N. L. Hazen, N. T. Allen, J. F. Oliver, N. W. Lanham, J. N. Demusz, E. E. Thompson, T. M. Allen, E. M. Weinstock, and A. E. Dessler. This work was supported by the NASA High Speed Research Program, under the direction of H. L. Wesoky, R. S. Stolarski, M. J. Prather, and K. Wolfe. Support for both the ER-2 and balloonbome instruments came from the NASA Upper Atmosphere Research Program under the direction of M. J. Kurylo. P. O. Wennberg acknowledges support from a Hughes Doctoral Research Fellowship. Finally, we thank our colleagues on the ER-2 ozone project.\n\nPublished - WENjas95.pdf
", "abstract": "Recent aircraft and balloon borne measurements of OH and HO_2 are reviewed. The authors demonstrate the ability of the laser-induced fluorescence technique to provide accurate, high signal to noise ratio measurements of OH throughout the upper troposphere and stratosphere. HO_2 is measured as OH after gas phase chemical titration with nitric oxide. The addition of the HO_x measurement capability to the suite of instruments aboard the NASA ER-2 aircraft has provided a wealth of new information about the processes that determine the concentration of ozone in the lower stratosphere. These simultaneous, in situ measurements provide a unique test of our understanding of the mechanisms that control the odd-hydrogen chemistry of the lower atmosphere.", "date": "1995-10-01", "date_type": "published", "publication": "Journal of the Atmospheric Sciences", "volume": "52", "number": "19", "publisher": "American Meteorological Society", "pagerange": "3413-3420", "id_number": "CaltechAUTHORS:20120216-144309952", "issn": "0022-4928", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20120216-144309952", "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(1995)052<3413:ISMOOA>2.0.CO;2", "primary_object": { "basename": "WENjas95.pdf", "url": "https://authors.library.caltech.edu/records/6xdp5-gca05/files/WENjas95.pdf" }, "resource_type": "article", "pub_year": "1995", "author_list": "Wennberg, P. O.; Hanisco, T. F.; et el." }, { "id": "https://authors.library.caltech.edu/records/avvvp-nde38", "eprint_id": 46803, "eprint_status": "archive", "datestamp": "2023-08-22 10:07:40", "lastmod": "2023-10-26 19:54:36", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Cohen-R-C", "name": { "family": "Cohen", "given": "R. C." }, "orcid": "0000-0001-6617-7691" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Stimpfle-R-M", "name": { "family": "Stimpfle", "given": "R. M." } }, { "id": "Koplow-J-P", "name": { "family": "Koplow", "given": "J." } }, { "id": "Anderson-J-G", "name": { "family": "Anderson", "given": "J. G." } }, { "id": "Fahey-D-W", "name": { "family": "Fahey", "given": "D. W." } }, { "id": "Woodbridge-E-L", "name": { "family": "Woodbridge", "given": "E. L." } }, { "id": "Keim-E-R", "name": { "family": "Keim", "given": "E. R." } }, { "id": "Gao-R", "name": { "family": "Gao", "given": "R." } }, { "id": "Proffitt-M-H", "name": { "family": "Proffitt", "given": "M. H." } }, { "id": "Loewenstein-M", "name": { "family": "Loewenstein", "given": "M." } }, { "id": "Chan-K-R", "name": { "family": "Chan", "given": "K. R." } } ] }, "title": "Are models of catalytic removal of O_3 by HO_x accurate? Constraints from in situ measurements of the OH to HO_2 ratio", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1994 American Geophysical Union. \n\nReceived March 21, 1994; revised June 7, 1994; accepted June 28, 1994. \n\nPaper number 94GL01713. \n\nThis work was supported by the NASA HSRP Program and the NASA High Altitude Branch.\n\nPublished - grl7772.pdf
", "abstract": "Measurements of the ratio OH/HO_2, NO, O_3, ClO, and BrO were obtained at altitudes from 15\u201320 km and latitudes from 15\u201360\u00b0N. A method is presented for interpreting these simultaneous in situ observations that constrains the rates of chemical transformations that 1) are responsible for over half the ozone removal rate in the lower stratosphere via reactions of HO_2 and 2) control the abundance of HO_2 through coupling to nitrogen and halogen radicals. The results show our understanding of the chemical reactions controlling the partitioning of OH and HO_2 is complete and accurate and that the potential effects of \"missing chemistry\" are strictly constrained in the region of the atmosphere encompassed by the observations. The analysis demonstrates that the sensitivity of the ratio OH/HO_2 to changes in NO is described to within 12% by current models. This reduces by more than a factor of 2 the effect of uncertainty in the coupling of hydrogen and nitrogen radicals on the analysis of the potential effects of perturbations to odd nitrogen in the lower stratosphere.", "date": "1994-11-15", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "21", "number": "23", "publisher": "American Geophysical Union", "pagerange": "2539-2542", "id_number": "CaltechAUTHORS:20140703-095145364", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140703-095145364", "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": "10.1029/94GL01713", "primary_object": { "basename": "grl7772.pdf", "url": "https://authors.library.caltech.edu/records/avvvp-nde38/files/grl7772.pdf" }, "resource_type": "article", "pub_year": "1994", "author_list": "Cohen, R. C.; Wennberg, P. O.; et el." }, { "id": "https://authors.library.caltech.edu/records/40bq2-pqe93", "eprint_id": 47258, "eprint_status": "archive", "datestamp": "2023-08-22 10:07:45", "lastmod": "2023-10-26 20:26:50", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Salawitch-R-J", "name": { "family": "Salawitch", "given": "R. J." } }, { "id": "Wofsy-S-C", "name": { "family": "Wofsy", "given": "S. C." }, "orcid": "0000-0002-3990-6737" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Cohen-R-C", "name": { "family": "Cohen", "given": "R. C." }, "orcid": "0000-0001-6617-7691" }, { "id": "Anderson-J-G", "name": { "family": "Anderson", "given": "J. G." } }, { "id": "Fahey-D-W", "name": { "family": "Fahey", "given": "D. W." } }, { "id": "Gao-R-S", "name": { "family": "Gao", "given": "R. S." } }, { "id": "Keim-E-R", "name": { "family": "Keim", "given": "E. R." } }, { "id": "Woodbridge-E-L", "name": { "family": "Woodbridge", "given": "E. L." } }, { "id": "Stimpfle-R-M", "name": { "family": "Stimpfle", "given": "R. M." } }, { "id": "Koplow-J-P", "name": { "family": "Koplow", "given": "J. P." } }, { "id": "Kohn-D-W", "name": { "family": "Kohn", "given": "D. W." } }, { "id": "Webster-C-R", "name": { "family": "Webster", "given": "C. R." } }, { "id": "May-R-D", "name": { "family": "May", "given": "R. D." } }, { "id": "Pfister-L", "name": { "family": "Pfister", "given": "L." } }, { "id": "Gottlieb-E-W", "name": { "family": "Gottlieb", "given": "E. W." } }, { "id": "Michelsen-H-A", "name": { "family": "Michelsen", "given": "H. A." } }, { "id": "Yue-G-K", "name": { "family": "Yue", "given": "G. K." } }, { "id": "Wilson-J-C", "name": { "family": "Wilson", "given": "J. C." } }, { "id": "Brock-C-A", "name": { "family": "Brock", "given": "C. A." } }, { "id": "Jonsson-H-H", "name": { "family": "Jonsson", "given": "H. H." }, "orcid": "0000-0003-3043-1074" }, { "id": "Dye-J-E", "name": { "family": "Dye", "given": "J. E." } }, { "id": "Baumgardner-D", "name": { "family": "Baumgardner", "given": "D." } }, { "id": "Proffitt-M-H", "name": { "family": "Proffitt", "given": "M. H." } }, { "id": "Loewenstein-M", "name": { "family": "Loewenstein", "given": "M." } }, { "id": "Podolske-J-R", "name": { "family": "Podolske", "given": "J. R." } }, { "id": "Elkins-J-W", "name": { "family": "Elkins", "given": "J. W." } }, { "id": "Dutton-G-S", "name": { "family": "Dutton", "given": "G. S." } }, { "id": "Hintsa-E-J", "name": { "family": "Hintsa", "given": "E. J." } }, { "id": "Dessler-A-E", "name": { "family": "Dessler", "given": "A. E." } }, { "id": "Weinstock-E-M", "name": { "family": "Weinstock", "given": "E. M." } }, { "id": "Kelly-K-K", "name": { "family": "Kelly", "given": "K. K." } }, { "id": "Boering-K-A", "name": { "family": "Boering", "given": "K. A." } }, { "id": "Daube-B-C-Jr", "name": { "family": "Daube", "given": "B. C." } }, { "id": "Chan-K-R", "name": { "family": "Chan", "given": "K. R." } }, { "id": "Bowen-S-W", "name": { "family": "Bowen", "given": "S. W." } } ] }, "title": "The distribution of hydrogen, nitrogen, and chlorine radicals in the lower stratosphere: Implications for changes in O_3 due to emission of NO_y from supersonic aircraft", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1994 American Geophysical Union. \n\nReceived: May 19, 1994; revised: August 29, 1994; accepted: September 7, 1994. \n\nPaper number 94GL02781. \n\nThis work was supported by NASA grants NAG2-731, NAGW-1230, NAS1-19955 and NSF grant ATM-89-21119 to Harvard University. We thank J. Herman and the GSFC processing team for providing data from TOMS and P. Newman and R. Nagatani for providing data from NMC.\n\nPublished - grl7983.pdf
", "abstract": "In situ measurements of hydrogen, nitrogen, and chlorine radicals obtained in the lower stratosphere during SPADE are compared to results from a photochemical model that assimilates measurements of radical precursors and environmental conditions. Models allowing for heterogeneous hydrolysis of N_2O_5 agree well with measured concentrations of NO and ClO, but concentrations of HO_2 and OH are underestimated by 10 to 25%, concentrations of NO_2 are overestimated by 10 to 30%, and concentrations of HCl are overestimated by a factor of 2. Discrepancies for [OH] and [HO_2] are reduced if we allow for higher yields of O(^1D) from O_3 photolysis and for heterogeneous production of HNO_2. The data suggest more efficient catalytic removal of O_3 by hydrogen and halogen radicals relative to nitrogen oxide radicals than predicted by models using recommended rates and cross sections. Increases in [O_3] in the lower stratosphere may be larger in response to inputs of NO_y from supersonic aircraft than estimated by current assessment models.", "date": "1994-11-15", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "21", "number": "23", "publisher": "American Geophysical Union", "pagerange": "2547-2550", "id_number": "CaltechAUTHORS:20140716-091039510", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140716-091039510", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NAG2-731" }, { "agency": "NASA", "grant_number": "NAGW-1230" }, { "agency": "NASA", "grant_number": "NAS1-19955" }, { "agency": "NSF", "grant_number": "ATM-89-21119" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/94GL02781", "primary_object": { "basename": "grl7983.pdf", "url": "https://authors.library.caltech.edu/records/40bq2-pqe93/files/grl7983.pdf" }, "resource_type": "article", "pub_year": "1994", "author_list": "Salawitch, R. J.; Wofsy, S. C.; et el." }, { "id": "https://authors.library.caltech.edu/records/kmgbb-ppp91", "eprint_id": 46627, "eprint_status": "archive", "datestamp": "2023-08-20 04:53:41", "lastmod": "2023-10-26 19:53:21", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Salawitch-Ross-J", "name": { "family": "Salawitch", "given": "R. J." }, "orcid": "0000-0001-8597-5832" }, { "id": "Wofsy-Steven-C", "name": { "family": "Wofsy", "given": "S. C." }, "orcid": "0000-0002-3133-2089" }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Cohen-Ronald-C", "name": { "family": "Cohen", "given": "R. C." }, "orcid": "0000-0001-6617-7691" }, { "id": "Anderson-J-G", "name": { "family": "Anderson", "given": "J. G." } }, { "id": "Fahey-David-W", "name": { "family": "Fahey", "given": "D. W." }, "orcid": "0000-0003-1720-0634" }, { "id": "Gao-R-S", "name": { "family": "Gao", "given": "R. S." } }, { "id": "Keim-E-R", "name": { "family": "Keim", "given": "E. R." } }, { "id": "Woodbridge-E-L", "name": { "family": "Woodbridge", "given": "E. L." } }, { "id": "Stimpfle-R-M", "name": { "family": "Stimpfle", "given": "R. M." } }, { "id": "Koplow-J-P", "name": { "family": "Koplow", "given": "J. P." } }, { "id": "Kohn-D-W", "name": { "family": "Kohn", "given": "D. W." } }, { "id": "Webster-C-R", "name": { "family": "Webster", "given": "C. R." } }, { "id": "May-R-D", "name": { "family": "May", "given": "R. D." } }, { "id": "Pfister-L", "name": { "family": "Pfister", "given": "L." } }, { "id": "Gottlieb-Elaine-W", "name": { "family": "Gottlieb", "given": "E. W." } }, { "id": "Michelsen-Hope-A", "name": { "family": "Michelsen", "given": "H. A." }, "orcid": "0000-0001-5802-6615" }, { "id": "Yue-G-K", "name": { "family": "Yue", "given": "G. K." } }, { "id": "Prather-Michael-J", "name": { "family": "Prather", "given": "M. J." }, "orcid": "0000-0002-9442-8109" }, { "id": "Wilson-J-C", "name": { "family": "Wilson", "given": "J. C." } }, { "id": "Brock-Charles-A", "name": { "family": "Brock", "given": "C. A." }, "orcid": "0000-0002-4033-4668" }, { "id": "Jonsson-Haflidi-H", "name": { "family": "Jonsson", "given": "H. H." }, "orcid": "0000-0003-3043-1074" }, { "id": "Dye-J-E", "name": { "family": "Dye", "given": "J. E." } }, { "id": "Baumgardner-Darrel", "name": { "family": "Baumgardner", "given": "D." } }, { "id": "Proffitt-M", "name": { "family": "Proffitt", "given": "M" } }, { "id": "Loewenstein-M", "name": { "family": "Loewenstein", "given": "M." } }, { "id": "Podolske-James-R", "name": { "family": "Podolske", "given": "J. R." }, "orcid": "0000-0003-2771-5375" }, { "id": "Elkins-James-W", "name": { "family": "Elkins", "given": "J. W." }, "orcid": "0000-0003-4701-3100" }, { "id": "Dutton-Geoffrey-S", "name": { "family": "Dutton", "given": "G. S." }, "orcid": "0000-0001-7777-9268" }, { "id": "Hintsa-Eric-J", "name": { "family": "Hintsa", "given": "E. J." }, "orcid": "0000-0002-5289-630X" }, { "id": "Dessler-A-E", "name": { "family": "Dessler", "given": "A. E." } }, { "id": "Weinstock-E-M", "name": { "family": "Weinstock", "given": "E. M." } }, { "id": "Kelly-K-K", "name": { "family": "Kelly", "given": "K. K." } }, { "id": "Boering-Kristie-A", "name": { "family": "Boering", "given": "K. A." }, "orcid": "0000-0003-0920-0503" }, { "id": "Daube-Bruce-C-Jr", "name": { "family": "Daube", "given": "B. C." } }, { "id": "Chan-K-R", "name": { "family": "Chan", "given": "K. R." } }, { "id": "Bowen-S-W", "name": { "family": "Bowen", "given": "S. W." } } ] }, "title": "The diurnal variation of hydrogen, nitrogen, and chlorine\n radicals: implications for the heterogeneous production of\n HNO\u2082", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1994 American Geophysical Union.\n\nManuscript Accepted: 19 OCT 1994; Manuscript Received: 29 AUG 1994.\n\nPaper number 94GL02782.\n\nThis work was supported by NASA grants NAG2-731, NAGW-1230, NAS1-19955 and NSF grant ATM-89-21119 to Harvard University. We thank J. Herman and the GSFC processing team for providing data from TOMS and P. Newman and R. Nagatani for providing data from NMC.\n\nPublished - grl7984.pdf
", "abstract": "In situ measurements of hydrogen, nitrogen, and chlorine radicals obtained through sunrise and sunset in the lower stratosphere during SPADE are compared to results from a photochemical model constrained by observed concentrations of radical precursors and environmental conditions. Models allowing for heterogeneous hydrolysis of N\u2082O\u2085 on sulfate aerosols agree with measured concentrations of NO, NO\u2082, and ClO throughout the day, but fail to account for high concentrations of OH and HO\u2082 observed near sunrise and sunset. The morning burst of [OH] and [HO\u2082] coincides with the rise of [NO] from photolysis of NO\u2082, suggesting a new source of HO\u2093 that photolyzes in the near UV (350 to 400 nm) spectral region. A model that allows for the heterogeneous production of HNO\u2082 results in an excellent simulation of the diurnal variations of [OH] and [HO\u2082].", "date": "1994-11-15", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "21", "number": "23", "publisher": "American Geophysical Union", "pagerange": "2551-2554", "id_number": "CaltechAUTHORS:20140702-094446231", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140702-094446231", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NAG2-731" }, { "agency": "NASA", "grant_number": "NAGW-1230" }, { "agency": "NASA", "grant_number": "NAS1-19955" }, { "agency": "NSF", "grant_number": "ATM-89-21119" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/94GL02782", "primary_object": { "basename": "grl7984.pdf", "url": "https://authors.library.caltech.edu/records/kmgbb-ppp91/files/grl7984.pdf" }, "resource_type": "article", "pub_year": "1994", "author_list": "Salawitch, R. J.; Wofsy, S. C.; et el." }, { "id": "https://authors.library.caltech.edu/records/vc8x4-q9m34", "eprint_id": 47278, "eprint_status": "archive", "datestamp": "2023-08-22 10:07:50", "lastmod": "2023-10-26 20:27:44", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Stimpfle-R-M", "name": { "family": "Stimpfle", "given": "R. M." } }, { "id": "Koplow-J-P", "name": { "family": "Koplow", "given": "J. P." } }, { "id": "Cohen-R-C", "name": { "family": "Cohen", "given": "R. C." }, "orcid": "0000-0001-6617-7691" }, { "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": "Judah-D-M", "name": { "family": "Judah", "given": "D. M." } }, { "id": "Toohey-D-W", "name": { "family": "Toohey", "given": "D. W." }, "orcid": "0000-0003-2853-1068" }, { "id": "Avallone-L-M", "name": { "family": "Avallone", "given": "L. M." } }, { "id": "Anderson-J-G", "name": { "family": "Anderson", "given": "J. G." } }, { "id": "Salawitch-R-J", "name": { "family": "Salawitch", "given": "R. J." } }, { "id": "Woodbridge-E-L", "name": { "family": "Woodbridge", "given": "E. L." } }, { "id": "Webster-C-R", "name": { "family": "Webster", "given": "C. R." } }, { "id": "May-R-D", "name": { "family": "May", "given": "R. D." } }, { "id": "Proffitt-M-H", "name": { "family": "Proffitt", "given": "M. H." } }, { "id": "Aiken-K", "name": { "family": "Aiken", "given": "K." } }, { "id": "Margitan-J", "name": { "family": "Margitan", "given": "J." } }, { "id": "Loewenstein-M", "name": { "family": "Loewenstein", "given": "M." } }, { "id": "Podolske-J-R", "name": { "family": "Podolske", "given": "J. R." } }, { "id": "Pfister-L", "name": { "family": "Pfister", "given": "L." } }, { "id": "Chan-K-R", "name": { "family": "Chan", "given": "K. R." } } ] }, "title": "The response of ClO radical concentrations to variations in NO_2 radical concentrations in the lower stratosphere", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1994 American Geophysical Union. \n\nManuscript Accepted: 29 Aug 1994. Manuscript Received: 22 Jun 1994. Paper number 94GL02373. \n\nWe thank the pilots and ground crew of the ER-2 based at NASA Ames Research Center. We thank J. Herman,R . McPeters and the NASA GSFC processing team for providing TOMS data. At Harvard we thank B. Heroux for providing Cl resonance lamps; and J. Demusz,N. Allen, N. Hazen, T. Martin,E . Thompson and E. Schomp for computer, software, electrical and mechanical support. This work was supported by NASA grants NAG-l-1305 and HSRP-92-659.\n\nPublished - grl7894.pdf
", "abstract": "The response of ClO concentrations to changes in NO_2 concentrations has been inferred from simultaneous observations of [ClO], [NO], [NO_2] and [O_3] in the mid-latitude lower stratosphere. This analysis demonstrates that [ClO] is inversely correlated with [NO_2], consistent with formation and photolysis of [ClONO_2]. A factor of ten range in the concentration of NO_2 was sampled (0.1 to 1\u00d710^9 mol/cm^3), with a comparable range in the ratio of [ClO] to total available inorganic chlorine (1% \u2264 [ClO]/[Cl_y] \u2264 5%). This analysis leads to an estimate of [ClONO_2]/[Cl_y] = 0.12 (\u00d7/\u00f72), in the mid-latitude, lower-stratospheric air masses sampled.", "date": "1994-11-15", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "21", "number": "23", "publisher": "American Geophysical Union", "pagerange": "2543-2546", "id_number": "CaltechAUTHORS:20140717-070108962", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140717-070108962", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NAG-1-1305" }, { "agency": "NASA", "grant_number": "HSRP-92-659" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/94GL02373", "primary_object": { "basename": "grl7894.pdf", "url": "https://authors.library.caltech.edu/records/vc8x4-q9m34/files/grl7894.pdf" }, "resource_type": "article", "pub_year": "1994", "author_list": "Stimpfle, R. M.; Koplow, J. P.; et el." }, { "id": "https://authors.library.caltech.edu/records/05z1b-p9k51", "eprint_id": 46502, "eprint_status": "archive", "datestamp": "2023-08-22 10:04:47", "lastmod": "2023-10-26 19:47:46", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Cohen-R-C", "name": { "family": "Cohen", "given": "R. C." }, "orcid": "0000-0001-6617-7691" }, { "id": "Stimpfle-R-M", "name": { "family": "Stimpfle", "given": "R. M." } }, { "id": "Koplow-J-P", "name": { "family": "Koplow", "given": "J. P." } }, { "id": "Anderson-J-G", "name": { "family": "Anderson", "given": "J. G." } }, { "id": "Salawitch-R-J", "name": { "family": "Salawitch", "given": "R. J." } }, { "id": "Fahey-D-W", "name": { "family": "Fahey", "given": "D. W." } }, { "id": "Woodbridge-E-L", "name": { "family": "Woodbridge", "given": "E. L." } }, { "id": "Keim-E-R", "name": { "family": "Keim", "given": "E. R." } }, { "id": "Gao-R-S", "name": { "family": "Gao", "given": "R. S." } }, { "id": "Webster-C-R", "name": { "family": "Webster", "given": "C. R." } }, { "id": "May-R-D", "name": { "family": "May", "given": "R. D." } }, { "id": "Toohey-D-W", "name": { "family": "Toohey", "given": "D. W." }, "orcid": "0000-0003-2853-1068" }, { "id": "Avallone-L-M", "name": { "family": "Avallone", "given": "L. M." } }, { "id": "Proffitt-M-H", "name": { "family": "Proffitt", "given": "M. H." } }, { "id": "Loewenstein-M", "name": { "family": "Loewenstein", "given": "M." } }, { "id": "Podolske-J-R", "name": { "family": "Podolske", "given": "J. R." } }, { "id": "Chan-K-R", "name": { "family": "Chan", "given": "K. R." } }, { "id": "Wofsy-S-C", "name": { "family": "Wofsy", "given": "S. C." }, "orcid": "0000-0002-3990-6737" } ] }, "title": "Removal of Stratospheric O_3 by Radicals: In Situ Measurements of OH, HO_2, NO, NO_2, CIO, AND BrO", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 1994 American Association for the Advancement of Science. \n\nReceived for publication 6 June 1994. Accepted for publication 1 September 1994. \n\nWe thank the pilots (W. Collette, J. Barrilleaux, D. Krumrey, J. Nystrum, and R. Williams) and the ground crews of the ER-2, without whom this work would not have been possible. ER-2 flight planning by P. A. Newman and co-workers from NASA-Goddard was instrumental to the success of SPADE. The TOMS UV reflectivity is produced by R. D. McPeters and co-workers of the NASA-Goddard ozone processing team; L. Pfister at NASA-Ames was responsible for interpolating this data onto the ER-2 flight track. New instrumentation for OH and HO_2 was developed in part by N. L. Hazen, L. B. Lapson, N. T.\nAllen, J. F. Oliver, N. W. Lanham, J. N. Demusz, E. E.\nThompson, T. L. Martin, E. M. Weinstock, and A. E.\nDessler at Harvard University. Interface with the ER-2\nwas supported by H. Kent, G. Prince, and R. York, at\nLockheed; their efforts are gratefully acknowledged.\nProgram support at NASA-Ames by J. C. Arveson, J. L. Barrilleaux, E. Condon, S. Wegner, and S. Hipskind\nis acknowledged. Finally, this work was supported by the NASA High Speed Research Program, under the direction of H. L. Wesoky, R. S. Stolarski, and M. J. Prather. Additional support for the HO, instrument development came from the NASA Upper Atmosphere Research Program, under the direction\nof M. J. Kurylo.", "abstract": "Simultaneous in situ measurements of the concentrations of OH, HO_2, ClO, BrO, NO, and NO_2 demonstrate the predominance of odd-hydrogen and halogen free-radical catalysis in determining the rate of removal of ozone in the lower stratosphere during May 1993. A single catalytic cycle, in which the rate-limiting step is the reaction of HO_2 with ozone, accounted for nearly one-half of the total O_3 removal in this region of the atmosphere. Halogen-radical chemistry was responsible for approximately one-third of the photochemical removal of O_3; reactions involving BrO account for one-half of this loss. Catalytic destruction by NO_2, which for two decades was considered to be the predominant loss process, accounted for less than 20 percent of the O_3 removal. The measurements demonstrate quantitatively the coupling that exists between the radical families. The concentrations of HO_2 and ClO are inversely correlated with those of NO and NO_2. The direct determination of the relative importance of the catalytic loss processes, combined with a demonstration of the reactions linking the hydrogen, halogen, and nitrogen radical concentrations, shows that in the air sampled the rate of O_3 removal was inversely correlated with total NO_x, loading.", "date": "1994-10-21", "date_type": "published", "publication": "Science", "volume": "266", "number": "5184", "publisher": "American Association for the Advancement of Science", "pagerange": "398-404", "id_number": "CaltechAUTHORS:20140625-105557166", "issn": "0036-8075", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140625-105557166", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Lockheed Corp." }, { "agency": "NASA" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1126/science.266.5184.398", "resource_type": "article", "pub_year": "1994", "author_list": "Wennberg, P. O.; Cohen, R. C.; et el." }, { "id": "https://authors.library.caltech.edu/records/rm18b-hz911", "eprint_id": 46804, "eprint_status": "archive", "datestamp": "2023-08-22 10:04:29", "lastmod": "2023-10-26 19:54:38", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Michelsen-H-A", "name": { "family": "Michelsen", "given": "H. A." } }, { "id": "Salawitch-R-J", "name": { "family": "Salawitch", "given": "R. J." } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Anderson-J-G", "name": { "family": "Anderson", "given": "J. G." } } ] }, "title": "Production of O(^1D) from photolysis of O_3", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1994 American Geophysical Union. \n\nReceived March 30, 1994; last revised July 8, 1994; accepted July 27, 1994. \n\nPaper number 94GL02052. \n\nWe thank the National Science Foundation for support of H. A. Michelsen through an NSF Postdoctoral Fellowship.\n\nPublished - grl7822.pdf
", "abstract": "We have used a model accounting for absorption by vibrationally and rotationally excited ozone (O_3) to examine published measurements of the quantum yield of O(^\u00b9D) and O_2(^\u00b9\u0394_g) from O_3 photolysis in the Huggins band (305\u2013325 nm). We conclude that the quantum yield of O(^\u00b9D) is 0.2\u20130.3 for wavelengths between 312 and 320 nm at 298 K; in contrast, the JPL recommended quantum yield of O(^\u00b9D) is negligible in this wavelength region. We present a compilation of our results at temperatures and wavelengths relevant to atmospheric calculations. Production of O(^\u00b9D) from excited O_3 increases calculated concentrations of O(^\u00b9D) by up to 40% and OH by 15% for the troposphere and lower stratosphere.", "date": "1994-10-01", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "21", "number": "20", "publisher": "American Geophysical Union", "pagerange": "2227-2230", "id_number": "CaltechAUTHORS:20140703-100410118", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140703-100410118", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF Postdoctoral Fellowship" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/94GL02052", "primary_object": { "basename": "grl7822.pdf", "url": "https://authors.library.caltech.edu/records/rm18b-hz911/files/grl7822.pdf" }, "resource_type": "article", "pub_year": "1994", "author_list": "Michelsen, H. A.; Salawitch, R. J.; et el." }, { "id": "https://authors.library.caltech.edu/records/qaw3t-9c618", "eprint_id": 47346, "eprint_status": "archive", "datestamp": "2023-08-22 10:03:22", "lastmod": "2023-10-26 20:31:04", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "Paul O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Anderson-J-G", "name": { "family": "Anderson", "given": "James G." } }, { "id": "Weisenstein-D-K", "name": { "family": "Weisenstein", "given": "Debra K." } } ] }, "title": "Kinetics of reactions of ground state nitrogen atoms (^4S_(3/2)) with NO and NO_2", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1994 American Geophysical Union. \n\nManuscript Accepted: 8 Jul 1994. Manuscript Received: 7 Mar 1994. Paper number 94JD01823. \n\nWe wish to thank P.S. Stevens and D.W. Toohey for experimental assistance. Discussions with J.P.D. Abbatt and Susan Solomon are gratefully acknowledged. This work was supported by NSF grant ATM-8601126. P. Wennberg acknowledges the support of the NSF Graduate Student Fellowship Program.\n\nPublished - jgrd3246.pdf
", "abstract": "The discharge flow technique has been used with resonance fluorescence detection of N atoms to study the fast radical-radical reaction of ground state nitrogen atoms (^4S_(3/2)) with NO and NO_2. The rate constants obtained are (in units of cm^3 molecule^(\u22121) s^(\u22121)) k_1 = (2.2\u00b10.2) \u00d7 10^(\u221211) exp[(160\u00b150)/T] in the temperature range 213 K \u2264 T \u2264 369 K for N + NO \u2192 N_2 + O and k_2 = (5.8\u00b10.5) \u00d7 10^(\u221212) exp [(220\u00b150)/T] in the temperature range 223 K \u2264 T \u2264 366 K for N + NO_2 \u2192 N_2O + O. The reported error limits are at the 95% confidence level. The reaction kinetics are consistent with other radical-radical reactions, essentially no enthalpic barrier is observed. Substitution of the measured rate of R_1 for the value recommended hi the latest Jet Propulsion Laboratory compendium [DeMore et al., 1992] results in a small change in the concentration of ozone predicted in a two-dimensional photochemical model. Modeled ozone concentrations are higher (approximately 1%) in the high-latitude upper stratosphere as a result of a 3\u201310% reduction in the calculated concentrations of NO_y.", "date": "1994-09-20", "date_type": "published", "publication": "Journal of Geophysical Research D", "volume": "99", "number": "D9", "publisher": "American Geophysical Union", "pagerange": "18839-18846", "id_number": "CaltechAUTHORS:20140718-144806995", "issn": "0148-0227", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140718-144806995", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "ATM-8601126" }, { "agency": "NSF Graduate Research Fellowship" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/94JD01823", "primary_object": { "basename": "jgrd3246.pdf", "url": "https://authors.library.caltech.edu/records/qaw3t-9c618/files/jgrd3246.pdf" }, "resource_type": "article", "pub_year": "1994", "author_list": "Wennberg, Paul O.; Anderson, James G.; et el." }, { "id": "https://authors.library.caltech.edu/records/2s6am-sv131", "eprint_id": 7575, "eprint_status": "archive", "datestamp": "2023-08-22 09:54:45", "lastmod": "2023-10-16 20:59:10", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Cohen-R-C", "name": { "family": "Cohen", "given": "R. C." }, "orcid": "0000-0001-6617-7691" }, { "id": "Hazen-N-L", "name": { "family": "Hazen", "given": "N. L." } }, { "id": "Lapson-L-B", "name": { "family": "Lapson", "given": "L. B." } }, { "id": "Allen-N-T", "name": { "family": "Allen", "given": "N. T." } }, { "id": "Hanisco-T-F", "name": { "family": "Hanisco", "given": "T. F." }, "orcid": "0000-0001-9434-8507" }, { "id": "Oliver-J-F", "name": { "family": "Oliver", "given": "J. F." } }, { "id": "Lanham-N-W", "name": { "family": "Lanham", "given": "N. W." } }, { "id": "Demusz-J-N", "name": { "family": "Demusz", "given": "J. N." } }, { "id": "Anderson-J-G", "name": { "family": "Anderson", "given": "J. G." } } ] }, "title": "Aircraft-borne, laser-induced fluorescence instrument for the in situ detection of hydroxyl and hydroperoxyl radicals", "ispublished": "pub", "full_text_status": "public", "keywords": "TROPOSPHERE; STRATOSPHERE; ATMOSPHERIC CHEMISTRY; HYDROXYL RADICALS; HYDROPEROXY RADICALS; CHEMICAL COMPOSITION; FLUORESCENCE SPECTROSCOPY; SIGNAL\u2212TO\u2212NOISE RATIO; AIRBORNE INSTRUMENTS", "note": "\u00a9 1994 American Institute of Physics. \n\nReceived 17 January 1994; accepted 4 March 1994) \n\nWe would like to thank the many individuals whose efforts led to the success of this experiment. At Harvard: E. Weinstock, A. Dessler, H. Michelsen, E. Thompson, T. Martin, E. Schomp, R. Mendelson, J, Canavan, D. Spillane, F. DeFreze, G. Graves, R. Heroux, K. Perkins, D. Chartrand, P. Guay, P. Rossi, J. Greer, and J. McDonough; At NASA Ames: S. Hipskind, E. Condon, and S. Wegener, J. Barrilleaux and the pilots of the ER-2. Cooperation with the Lockheed engineering staff, H. Kent, G. Prince, and R. York, is gratefully acknowledged. A special thanks to A. Schmeltekopf for his support before and help during the integration of the instrument onto the aircraft. This project would not have been possible without the pioneering work of R.M. Stimpfle. This work funded in part by the NASA HSRP Program with addition support from the NASA High Altitude Branch. P.O. Wennberg gratefully acknowledges personal support from NSF and Hughes Graduate Fellowships.\n\nPublished - WENrsi94.pdf
", "abstract": "The odd-hydrogen radicals OH and HO2 are central to most of the gas-phase chemical transformations that occur in the atmosphere. Of particular interest is the role that these species play in controlling the concentration of stratospheric ozone. This paper describes an instrument that measures both of these species at volume mixing ratios below one part in 10^14 in the upper troposphere and lower stratosphere. The hydroxyl radical (OH) is measured by laser induced fluorescence at 309 nm. Tunable UV light is used to pump OH to the first electronic state (A-tilde 2Sigma+(v[script ']=1) <-- X-tilde 2Pi3/2 (v[script `]=0)) near 282 nm. The laser light is produced by a high-repetition rate pulsed dye-laser powered with all solid-state pump lasers. HO2 is measured as OH after gas-phase titration with nitric oxide. Measurements aboard a NASA ER-2 aircraft demonstrate the capability of this instrument to perform reliably with very high signal-to-noise ratios (>~30) achieved in short integration times (< 20 sec).", "date": "1994-06", "date_type": "published", "publication": "Review of Scientific Instruments", "volume": "65", "number": "6", "publisher": "American Institute of Physics", "pagerange": "1858-1876", "id_number": "CaltechAUTHORS:WENrsi94", "issn": "0034-6748", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:WENrsi94", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA" }, { "agency": "NSF" }, { "agency": "Hughes Graduate Fellowship" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1063/1.1144835", "primary_object": { "basename": "WENrsi94.pdf", "url": "https://authors.library.caltech.edu/records/2s6am-sv131/files/WENrsi94.pdf" }, "resource_type": "article", "pub_year": "1994", "author_list": "Wennberg, P. O.; Cohen, R. C.; et el." }, { "id": "https://authors.library.caltech.edu/records/q5yex-fme83", "eprint_id": 46593, "eprint_status": "archive", "datestamp": "2023-08-22 07:45:56", "lastmod": "2023-10-26 19:51:47", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Stimpfle-R-M", "name": { "family": "Stimpfle", "given": "R. M." } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Lapson-L-B", "name": { "family": "Lapson", "given": "L. B." } }, { "id": "Anderson-J-G", "name": { "family": "Anderson", "given": "J. G." } } ] }, "title": "Simultaneous, in situ measurements of OH and HO_2 in the stratosphere", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1990 American Geophysical Union. \n\nReceived July 12, 1990; accepted August 6, 1990. \n\nThis flight could not have been carried out without the special assistance on short notice of a large number of individuals : At NASA headquarters, Bob Watson; at NSBF, Danny Ball and the support staff, which provided excellent assistance; and at Harvard, E. Weinstock, J. Demusz, N. Hazen, B. Heroux, T. Schiller, D. Spillane and E. Thompson. Funds provided by NASA contract NASW 3960.\n\nPublished - grl5072.pdf
", "abstract": "Stratospheric OH and HO_2 radical densities have been measured between 36 and 23 km using a balloon-borne, in situ instrument launched from Palestine, TX on August 25, 1989. OH is detected using the laser-induced fluorescence technique (LIF) employing a Cu-vapor-laser pumped dye laser coupled with an enclosed-flow detection chamber. HO_2 is detected nearly simultaneously by adding No to the sample flow to convert ambient HO_2 to OH. Observed OH and HO_2 densities ranged from 8.0 \u00b1 2.8 \u00d7 10^6 and 1.4 \u00b1 0.5 \u00d7 10^7 molec cm^(\u22123), respectively, at 36 km, to 1.4\u00b1 0.5 \u00d7 10^6 and 3.0\u00b1 1.0 \u00d7 10^6 at 23 km, where the uncertainty is \u00b11\u03c3. The HO_2 density exhibits a maximum in the 34\u201330 km of 1.7\u00b10.6 \u00d7 10^7. The data were obtained over a solar zenith angle variation of 51\u00b0 at 36 km to 61\u00b0 at 23 km. O_3 and H_2O densities also were measured simultaneously with separate instruments.", "date": "1990-10", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "17", "number": "11", "publisher": "American Geophysical Union", "pagerange": "1905-1908", "id_number": "CaltechAUTHORS:20140701-100608349", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140701-100608349", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NASW 3960" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/GL017i011p01905", "primary_object": { "basename": "grl5072.pdf", "url": "https://authors.library.caltech.edu/records/q5yex-fme83/files/grl5072.pdf" }, "resource_type": "article", "pub_year": "1990", "author_list": "Stimpfle, R. M.; Wennberg, P. O.; et el." }, { "id": "https://authors.library.caltech.edu/records/qjmzt-vnd14", "eprint_id": 46801, "eprint_status": "archive", "datestamp": "2023-08-22 07:46:01", "lastmod": "2023-10-26 19:54:32", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Stimpfle-R-M", "name": { "family": "Stimpfle", "given": "R. M." } }, { "id": "Weinstock-E-M", "name": { "family": "Weinstock", "given": "E. M." } }, { "id": "Dessler-A-E", "name": { "family": "Dessler", "given": "A. E." } }, { "id": "Lloyd-S-A", "name": { "family": "Lloyd", "given": "S. A." } }, { "id": "Lapson-L-B", "name": { "family": "Lapson", "given": "L. B." } }, { "id": "Schwab-J-J", "name": { "family": "Schwab", "given": "J. J." } }, { "id": "Anderson-J-G", "name": { "family": "Anderson", "given": "J. G." } } ] }, "title": "Simultaneous, in situ measurements of OH, HO_2, O_3, and H_2O: A test of modeled stratospheric HO_x chemistry", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1990 American Geophysical Union. \n\nReceived: 12 Jul 1990. Accepted: 6 Aug 1990. \n\nPaper number: 90GL01826. \n\nThis flight could not have been carried out with out the special assistance on short notice of: at NASA headquarters, R. Watson; at NSBF, D. Ball and the NSBF support staff; at Harvard, J. Demusz, N. Hazen, B. Heroux, T. Schiller, D. Spillane, and E. Thompson, P. Wennberg acknowledged the support of NSF Graduate Fellowship. Funds provided by NASA contract NASW 3960.\n\nPublished - grl5073.pdf
", "abstract": "Simultaneous, in situ measurements of OH, HO_2, H_2O, and O_3 from 37\u201323 km are reported. The partitioning between OH and HO_2 and the total HO_x concentration are compared with expected steady-state values. The ratio of HO_2 to OH varies from less than 2 at 36 km to more than 3 at 25 km; in the lower stratosphere this ratio is nearly a factor of two less than predicted. The data are used to calculate HO_x production and loss rates. The measured HOx mixing ratio is consistent with production dominated by the reaction of O(1D) with H_2O, and loss controlled by NO_y below 28 km and HO_x above 30 km. The steady-state concentration of H_2O_2 is inferred from the measured HO_2 concentration and calculated photolysis rate. The maximum H_2O_2 mixing ratio (at 33 km) is predicted to be less than 0.2 ppb.", "date": "1990-10", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "17", "number": "11", "publisher": "American Geophysical Union", "pagerange": "1909-1912", "id_number": "CaltechAUTHORS:20140703-091548721", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140703-091548721", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF Graduate Research Fellowship" }, { "agency": "NASA", "grant_number": "NASW 3960" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/GL017i011p01909", "primary_object": { "basename": "grl5073.pdf", "url": "https://authors.library.caltech.edu/records/qjmzt-vnd14/files/grl5073.pdf" }, "resource_type": "article", "pub_year": "1990", "author_list": "Wennberg, P. O.; Stimpfle, R. M.; et el." }, { "id": "https://authors.library.caltech.edu/records/z603e-gp890", "eprint_id": 49639, "eprint_status": "archive", "datestamp": "2023-08-22 06:58:33", "lastmod": "2023-10-17 21:36:09", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Stimpfle-R-M", "name": { "family": "Stimpfle", "given": "R. M." } }, { "id": "Lapson-L-B", "name": { "family": "Lapson", "given": "L. B." } }, { "id": "Wennberg-P-O", "name": { "family": "Wennberg", "given": "P. O." }, "orcid": "0000-0002-6126-3854" }, { "id": "Anderson-J-G", "name": { "family": "Anderson", "given": "J. G." } } ] }, "title": "Balloon borne in-situ detection of OH in the stratosphere from 37 to 23 km", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1989 American Geophysical Union. \n\nReceived: September 19, 1989; revised: October 25, 1989; accepted: October 26, 1989. \n\nPaper number 89GL03359. \n\nWe are indebted to J. Demusz, N. Allen, M. Mueller, N. Hazen, B. Heroux, E. Weinstock and the Atmospheric Research Group staff. The NSBF staff in Palestine, TX provided excellent support. Funds for this research were provided by NASA contract NASW 3960.\n\nPublished - grl4570.pdf
", "abstract": "The OH number density in the stratosphere has been measured over the altitude interval of 37 to 23 km at midday via a balloon-borne gondola launched from Palestine, Texas on July 6, 1988. OH radicals are detected with a laser induced fluorescence instrument employing a 17 kHz repetition rate copper vapor laser pumped dye laser optically coupled to an enclosed flow, in-situ sampling chamber. OH abundances ranged from 88\u00b131 pptv (1.1 \u00b1 0.4 \u00d7 10^7 molec cm^(\u22123)) in the 36 to 35 km interval to 0.9 \u00b1 0.8 pptv (8.7 \u00b1 7.7 \u00d7 10^5 molec cm^(\u22123)) in the 24 to 23 km interval. The stated uncertainty (\u00b11\u03c3) includes that from both measurement precision and accuracy. Simultaneous detection of ozone and water vapor densities was carried out with separate on-board instruments.", "date": "1989-12", "date_type": "published", "publication": "Geophysical Research Letters", "volume": "16", "number": "12", "publisher": "American Geophysical Union", "pagerange": "1433-1436", "id_number": "CaltechAUTHORS:20140912-084956282", "issn": "0094-8276", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140912-084956282", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA", "grant_number": "NASW-3960" } ] }, "local_group": { "items": [ { "id": "Division-of-Geological-and-Planetary-Sciences" } ] }, "doi": "10.1029/GL016i012p01433", "primary_object": { "basename": "grl4570.pdf", "url": "https://authors.library.caltech.edu/records/z603e-gp890/files/grl4570.pdf" }, "resource_type": "article", "pub_year": "1989", "author_list": "Stimpfle, R. M.; Lapson, L. B.; et el." } ]