Articles | Volume 7, issue 9
https://doi.org/10.5194/amt-7-2787-2014
© Author(s) 2014. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
https://doi.org/10.5194/amt-7-2787-2014
© Author(s) 2014. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Research article
| 
03 Sep 2014
Research article |
| 03 Sep 2014
Ecosystem fluxes of hydrogen: a comparison of flux-gradient methods
L. K. Meredith
Center for Global Change Science, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA
now at: Environmental Earth System Science, Stanford University, Stanford, California, USA
R. Commane
School of Engineering and Applied Sciences and Department of Earth and Planetary Sciences, Harvard University, Cambridge, Massachusetts, USA
J. W. Munger
School of Engineering and Applied Sciences and Department of Earth and Planetary Sciences, Harvard University, Cambridge, Massachusetts, USA
A. Dunn
Department of Physical and Earth Science, Worcester State University, Worcester, Massachusetts, USA
Ecosystems Center, Marine Biological Laboratory, Woods Hole, Massachusetts, USA
S. C. Wofsy
School of Engineering and Applied Sciences and Department of Earth and Planetary Sciences, Harvard University, Cambridge, Massachusetts, USA
R. G. Prinn
Center for Global Change Science, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA
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Maria Tzortziou, Charlotte F. Kwong, Daniel Goldberg, Luke Schiferl, Róisín Commane, Nader Abuhassan, James J. Szykman, and Lukas C. Valin
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Anna-Maria Virkkala, Susan M. Natali, Brendan M. Rogers, Jennifer D. Watts, Kathleen Savage, Sara June Connon, Marguerite Mauritz, Edward A. G. Schuur, Darcy Peter, Christina Minions, Julia Nojeim, Roisin Commane, Craig A. Emmerton, Mathias Goeckede, Manuel Helbig, David Holl, Hiroki Iwata, Hideki Kobayashi, Pasi Kolari, Efrén López-Blanco, Maija E. Marushchak, Mikhail Mastepanov, Lutz Merbold, Frans-Jan W. Parmentier, Matthias Peichl, Torsten Sachs, Oliver Sonnentag, Masahito Ueyama, Carolina Voigt, Mika Aurela, Julia Boike, Gerardo Celis, Namyi Chae, Torben R. Christensen, M. Syndonia Bret-Harte, Sigrid Dengel, Han Dolman, Colin W. Edgar, Bo Elberling, Eugenie Euskirchen, Achim Grelle, Juha Hatakka, Elyn Humphreys, Järvi Järveoja, Ayumi Kotani, Lars Kutzbach, Tuomas Laurila, Annalea Lohila, Ivan Mammarella, Yojiro Matsuura, Gesa Meyer, Mats B. Nilsson, Steven F. Oberbauer, Sang-Jong Park, Roman Petrov, Anatoly S. Prokushkin, Christopher Schulze, Vincent L. St. Louis, Eeva-Stiina Tuittila, Juha-Pekka Tuovinen, William Quinton, Andrej Varlagin, Donatella Zona, and Viacheslav I. Zyryanov
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Jennifer D. Hegarty, Karen E. Cady-Pereira, Vivienne H. Payne, Susan S. Kulawik, John R. Worden, Valentin Kantchev, Helen M. Worden, Kathryn McKain, Jasna V. Pittman, Róisín Commane, Bruce C. Daube Jr., and Eric A. Kort
Atmos. Meas. Tech., 15, 205–223, https://doi.org/10.5194/amt-15-205-2022, https://doi.org/10.5194/amt-15-205-2022, 2022
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Juliana Gil-Loaiza, Joseph R. Roscioli, Joanne H. Shorter, Till H. M. Volkmann, Wei-Ren Ng, Jordan E. Krechmer, and Laura K. Meredith
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Linda M. J. Kooijmans, Ara Cho, Jin Ma, Aleya Kaushik, Katherine D. Haynes, Ian Baker, Ingrid T. Luijkx, Mathijs Groenink, Wouter Peters, John B. Miller, Joseph A. Berry, Jerome Ogée, Laura K. Meredith, Wu Sun, Kukka-Maaria Kohonen, Timo Vesala, Ivan Mammarella, Huilin Chen, Felix M. Spielmann, Georg Wohlfahrt, Max Berkelhammer, Mary E. Whelan, Kadmiel Maseyk, Ulli Seibt, Roisin Commane, Richard Wehr, and Maarten Krol
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Eric J. Hintsa, Fred L. Moore, Dale F. Hurst, Geoff S. Dutton, Bradley D. Hall, J. David Nance, Ben R. Miller, Stephen A. Montzka, Laura P. Wolton, Audra McClure-Begley, James W. Elkins, Emrys G. Hall, Allen F. Jordan, Andrew W. Rollins, Troy D. Thornberry, Laurel A. Watts, Chelsea R. Thompson, Jeff Peischl, Ilann Bourgeois, Thomas B. Ryerson, Bruce C. Daube, Yenny Gonzalez Ramos, Roisin Commane, Gregory W. Santoni, Jasna V. Pittman, Steven C. Wofsy, Eric Kort, Glenn S. Diskin, and T. Paul Bui
Atmos. Meas. Tech., 14, 6795–6819, https://doi.org/10.5194/amt-14-6795-2021, https://doi.org/10.5194/amt-14-6795-2021, 2021
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We built UCATS to study atmospheric chemistry and transport. It has measured trace gases including CFCs, N2O, SF6, CH4, CO, and H2 with gas chromatography, as well as ozone and water vapor. UCATS has been part of missions to study the tropical tropopause; transport of air into the stratosphere; greenhouse gases, transport, and chemistry in the troposphere; and ozone chemistry, on both piloted and unmanned aircraft. Its design, capabilities, and some results are shown and described here.
Charles A. Brock, Karl D. Froyd, Maximilian Dollner, Christina J. Williamson, Gregory Schill, Daniel M. Murphy, Nicholas J. Wagner, Agnieszka Kupc, Jose L. Jimenez, Pedro Campuzano-Jost, Benjamin A. Nault, Jason C. Schroder, Douglas A. Day, Derek J. Price, Bernadett Weinzierl, Joshua P. Schwarz, Joseph M. Katich, Siyuan Wang, Linghan Zeng, Rodney Weber, Jack Dibb, Eric Scheuer, Glenn S. Diskin, Joshua P. DiGangi, ThaoPaul Bui, Jonathan M. Dean-Day, Chelsea R. Thompson, Jeff Peischl, Thomas B. Ryerson, Ilann Bourgeois, Bruce C. Daube, Róisín Commane, and Steven C. Wofsy
Atmos. Chem. Phys., 21, 15023–15063, https://doi.org/10.5194/acp-21-15023-2021, https://doi.org/10.5194/acp-21-15023-2021, 2021
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The Atmospheric Tomography Mission was an airborne study that mapped the chemical composition of the remote atmosphere. From this, we developed a comprehensive description of aerosol properties that provides a unique, global-scale dataset against which models can be compared. The data show the polluted nature of the remote atmosphere in the Northern Hemisphere and quantify the contributions of sea salt, dust, soot, biomass burning particles, and pollution particles to the haziness of the sky.
Hao Guo, Clare M. Flynn, Michael J. Prather, Sarah A. Strode, Stephen D. Steenrod, Louisa Emmons, Forrest Lacey, Jean-Francois Lamarque, Arlene M. Fiore, Gus Correa, Lee T. Murray, Glenn M. Wolfe, Jason M. St. Clair, Michelle Kim, John Crounse, Glenn Diskin, Joshua DiGangi, Bruce C. Daube, Roisin Commane, Kathryn McKain, Jeff Peischl, Thomas B. Ryerson, Chelsea Thompson, Thomas F. Hanisco, Donald Blake, Nicola J. Blake, Eric C. Apel, Rebecca S. Hornbrook, James W. Elkins, Eric J. Hintsa, Fred L. Moore, and Steven Wofsy
Atmos. Chem. Phys., 21, 13729–13746, https://doi.org/10.5194/acp-21-13729-2021, https://doi.org/10.5194/acp-21-13729-2021, 2021
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The NASA Atmospheric Tomography (ATom) mission built a climatology of the chemical composition of tropospheric air parcels throughout the middle of the Pacific and Atlantic oceans. The level of detail allows us to reconstruct the photochemical budgets of O3 and CH4 over these vast, remote regions. We find that most of the chemical heterogeneity is captured at the resolution used in current global chemistry models and that the majority of reactivity occurs in the
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Yenny Gonzalez, Róisín Commane, Ethan Manninen, Bruce C. Daube, Luke D. Schiferl, J. Barry McManus, Kathryn McKain, Eric J. Hintsa, James W. Elkins, Stephen A. Montzka, Colm Sweeney, Fred Moore, Jose L. Jimenez, Pedro Campuzano Jost, Thomas B. Ryerson, Ilann Bourgeois, Jeff Peischl, Chelsea R. Thompson, Eric Ray, Paul O. Wennberg, John Crounse, Michelle Kim, Hannah M. Allen, Paul A. Newman, Britton B. Stephens, Eric C. Apel, Rebecca S. Hornbrook, Benjamin A. Nault, Eric Morgan, and Steven C. Wofsy
Atmos. Chem. Phys., 21, 11113–11132, https://doi.org/10.5194/acp-21-11113-2021, https://doi.org/10.5194/acp-21-11113-2021, 2021
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Elizabeth B. Wiggins, Arlyn Andrews, Colm Sweeney, John B. Miller, Charles E. Miller, Sander Veraverbeke, Roisin Commane, Steven Wofsy, John M. Henderson, and James T. Randerson
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We analyzed high-resolution trace gas measurements collected from a tower in Alaska during a very active fire season to improve our understanding of trace gas emissions from boreal forest fires. Our results suggest previous studies may have underestimated emissions from smoldering combustion in boreal forest fires.
Fabienne Maignan, Camille Abadie, Marine Remaud, Linda M. J. Kooijmans, Kukka-Maaria Kohonen, Róisín Commane, Richard Wehr, J. Elliott Campbell, Sauveur Belviso, Stephen A. Montzka, Nina Raoult, Ulli Seibt, Yoichi P. Shiga, Nicolas Vuichard, Mary E. Whelan, and Philippe Peylin
Biogeosciences, 18, 2917–2955, https://doi.org/10.5194/bg-18-2917-2021, https://doi.org/10.5194/bg-18-2917-2021, 2021
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The assimilation of carbonyl sulfide (COS) by continental vegetation has been proposed as a proxy for gross primary production (GPP). Using a land surface and a transport model, we compare a mechanistic representation of the plant COS uptake (Berry et al., 2013) to the classical leaf relative uptake (LRU) approach linking GPP and vegetation COS fluxes. We show that at high temporal resolutions a mechanistic approach is mandatory, but at large scales the LRU approach compares similarly.
Junjie Liu, Latha Baskaran, Kevin Bowman, David Schimel, A. Anthony Bloom, Nicholas C. Parazoo, Tomohiro Oda, Dustin Carroll, Dimitris Menemenlis, Joanna Joiner, Roisin Commane, Bruce Daube, Lucianna V. Gatti, Kathryn McKain, John Miller, Britton B. Stephens, Colm Sweeney, and Steven Wofsy
Earth Syst. Sci. Data, 13, 299–330, https://doi.org/10.5194/essd-13-299-2021, https://doi.org/10.5194/essd-13-299-2021, 2021
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On average, the terrestrial biosphere carbon sink is equivalent to ~ 20 % of fossil fuel emissions. Understanding where and why the terrestrial biosphere absorbs carbon from the atmosphere is pivotal to any mitigation policy. Here we present a regionally resolved satellite-constrained net biosphere exchange (NBE) dataset with corresponding uncertainties between 2010–2018: CMS-Flux NBE 2020. The dataset provides a unique perspective on monitoring regional contributions to the CO2 growth rate.
Sara Martínez-Alonso, Merritt Deeter, Helen Worden, Tobias Borsdorff, Ilse Aben, Róisin Commane, Bruce Daube, Gene Francis, Maya George, Jochen Landgraf, Debbie Mao, Kathryn McKain, and Steven Wofsy
Atmos. Meas. Tech., 13, 4841–4864, https://doi.org/10.5194/amt-13-4841-2020, https://doi.org/10.5194/amt-13-4841-2020, 2020
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CO is of great importance in climate and air quality studies. To understand newly available TROPOMI data in the frame of the global CO record, we compared those to satellite (MOPITT) and airborne (ATom) CO datasets. The MOPITT dataset is the longest to date (2000–present) and is well-characterized. We used ATom to validate cloudy TROPOMI data over oceans and investigate TROPOMI's vertical sensitivity to CO. Our results show that TROPOMI CO data are in excellent agreement with the other datasets.
Ilann Bourgeois, Jeff Peischl, Chelsea R. Thompson, Kenneth C. Aikin, Teresa Campos, Hannah Clark, Róisín Commane, Bruce Daube, Glenn W. Diskin, James W. Elkins, Ru-Shan Gao, Audrey Gaudel, Eric J. Hintsa, Bryan J. Johnson, Rigel Kivi, Kathryn McKain, Fred L. Moore, David D. Parrish, Richard Querel, Eric Ray, Ricardo Sánchez, Colm Sweeney, David W. Tarasick, Anne M. Thompson, Valérie Thouret, Jacquelyn C. Witte, Steve C. Wofsy, and Thomas B. Ryerson
Atmos. Chem. Phys., 20, 10611–10635, https://doi.org/10.5194/acp-20-10611-2020, https://doi.org/10.5194/acp-20-10611-2020, 2020
Katherine R. Travis, Colette L. Heald, Hannah M. Allen, Eric C. Apel, Stephen R. Arnold, Donald R. Blake, William H. Brune, Xin Chen, Róisín Commane, John D. Crounse, Bruce C. Daube, Glenn S. Diskin, James W. Elkins, Mathew J. Evans, Samuel R. Hall, Eric J. Hintsa, Rebecca S. Hornbrook, Prasad S. Kasibhatla, Michelle J. Kim, Gan Luo, Kathryn McKain, Dylan B. Millet, Fred L. Moore, Jeffrey Peischl, Thomas B. Ryerson, Tomás Sherwen, Alexander B. Thames, Kirk Ullmann, Xuan Wang, Paul O. Wennberg, Glenn M. Wolfe, and Fangqun Yu
Atmos. Chem. Phys., 20, 7753–7781, https://doi.org/10.5194/acp-20-7753-2020, https://doi.org/10.5194/acp-20-7753-2020, 2020
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Atmospheric models overestimate the rate of removal of trace gases by the hydroxyl radical (OH). This is a concern for studies of the climate and air quality impacts of human activities. Here, we evaluate the performance of a commonly used model of atmospheric chemistry against data from the NASA Atmospheric Tomography Mission (ATom) over the remote oceans where models have received little validation. The model is generally successful, suggesting that biases in OH may be a concern over land.
Alexander B. Thames, William H. Brune, David O. Miller, Hannah M. Allen, Eric C. Apel, Donald R. Blake, T. Paul Bui, Roisin Commane, John D. Crounse, Bruce C. Daube, Glenn S. Diskin, Joshua P. DiGangi, James W. Elkins, Samuel R. Hall, Thomas F. Hanisco, Reem A. Hannun, Eric Hintsa, Rebecca S. Hornbrook, Michelle J. Kim, Kathryn McKain, Fred L. Moore, Julie M. Nicely, Jeffrey Peischl, Thomas B. Ryerson, Jason M. St. Clair, Colm Sweeney, Alex Teng, Chelsea R. Thompson, Kirk Ullmann, Paul O. Wennberg, and Glenn M. Wolfe
Atmos. Chem. Phys., 20, 4013–4029, https://doi.org/10.5194/acp-20-4013-2020, https://doi.org/10.5194/acp-20-4013-2020, 2020
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Oceans and the atmosphere exchange volatile gases that react with the hydroxyl radical (OH). During a NASA airborne study, measurements of the total frequency of OH reactions, called the OH reactivity, were made in the marine boundary layer of the Atlantic and Pacific oceans. The measured OH reactivity often exceeded the OH reactivity calculated from measured chemical species. This missing OH reactivity appears to be from unmeasured volatile organic compounds coming out of the ocean.
Archana Dayalu, J. William Munger, Yuxuan Wang, Steven C. Wofsy, Yu Zhao, Thomas Nehrkorn, Chris Nielsen, Michael B. McElroy, and Rachel Chang
Atmos. Chem. Phys., 20, 3569–3588, https://doi.org/10.5194/acp-20-3569-2020, https://doi.org/10.5194/acp-20-3569-2020, 2020
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China has pledged to reduce carbon dioxide emissions per unit GDP by 60–65 % relative to 2005 levels, and to peak carbon emissions overall by 2030. Disagreement among available inventories of Chinese emissions makes it difficult for China to track progress toward its goals and evaluate the efficacy of regional control measures. This study uses a unique set of historical atmospheric observations for the key period from 2005 to 2009 to independently evaluate three different CO2 emission estimates.
Mark O. Battle, J. William Munger, Margaret Conley, Eric Sofen, Rebecca Perry, Ryan Hart, Zane Davis, Jacob Scheckman, Jayme Woogerd, Karina Graeter, Samuel Seekins, Sasha David, and John Carpenter
Atmos. Chem. Phys., 19, 8687–8701, https://doi.org/10.5194/acp-19-8687-2019, https://doi.org/10.5194/acp-19-8687-2019, 2019
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Predictions of global warming require predictions of how much CO2 will be taken up by the oceans, how much by land plants, and how much will stay in the atmosphere. Measurements of atmospheric oxygen (O2) help with these predictions if we also know the ratio of O2 release to CO2 uptake in land plants. We have measured this ratio in a midlatitude forest and find a lower value than the one in wide use. If truly applicable, our results call for a modest adjustment in the global carbon budget.
Shaojie Song, Meng Gao, Weiqi Xu, Yele Sun, Douglas R. Worsnop, John T. Jayne, Yuzhong Zhang, Lei Zhu, Mei Li, Zhen Zhou, Chunlei Cheng, Yibing Lv, Ying Wang, Wei Peng, Xiaobin Xu, Nan Lin, Yuxuan Wang, Shuxiao Wang, J. William Munger, Daniel J. Jacob, and Michael B. McElroy
Atmos. Chem. Phys., 19, 1357–1371, https://doi.org/10.5194/acp-19-1357-2019, https://doi.org/10.5194/acp-19-1357-2019, 2019
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Chemistry responsible for sulfate production in northern China winter haze remains mysterious. We propose a potentially key pathway through the reaction of formaldehyde and sulfur dioxide that has not been accounted for in previous studies. The special atmospheric conditions favor the formation and existence of their complex, hydroxymethanesulfonate (HMS).
Archana Dayalu, J. William Munger, Steven C. Wofsy, Yuxuan Wang, Thomas Nehrkorn, Yu Zhao, Michael B. McElroy, Chris P. Nielsen, and Kristina Luus
Biogeosciences, 15, 6713–6729, https://doi.org/10.5194/bg-15-6713-2018, https://doi.org/10.5194/bg-15-6713-2018, 2018
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Accounting for the vegetation signal is critical for comprehensive CO2 budget assessment in China. We model and evaluate hourly vegetation carbon dioxide (CO2) exchange (mass per unit area per unit time) in northern China from 2005 to 2009. The model is driven by satellite and meteorological data, is linked to ground-level ecosystem observations, and is applicable to other time periods. We find vegetation uptake of CO2 in summer is comparable to emissions from fossil fuels in northern China.
Archana Dayalu, J. William Munger, Yuxuan Wang, Steven C. Wofsy, Yu Zhao, Thomas Nehrkorn, Chris Nielsen, Michael B. McElroy, and Rachel Chang
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2018-632, https://doi.org/10.5194/acp-2018-632, 2018
Revised manuscript not accepted
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China has pledged reduction of carbon dioxide emissions per unit GDP by 60–65 % relative to 2005 levels, and to peak carbon emissions overall by 2030. Disagreement among available inventories of Chinese emissions makes it difficult for China to track progress toward its goals and evaluate the efficacy of regional control measures. This study uses a unique set of historical atmospheric observations for the key period from 2005–2009 to independently evaluate three different CO2 emissions estimates.
Jason A. Ducker, Christopher D. Holmes, Trevor F. Keenan, Silvano Fares, Allen H. Goldstein, Ivan Mammarella, J. William Munger, and Jordan Schnell
Biogeosciences, 15, 5395–5413, https://doi.org/10.5194/bg-15-5395-2018, https://doi.org/10.5194/bg-15-5395-2018, 2018
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We have developed an accurate method (SynFlux) to estimate ozone deposition and stomatal uptake across 103 flux tower sites (43 US, 60 Europe), where ozone concentrations and fluxes have not been measured. In all, the SynFlux public dataset provides monthly values of ozone dry deposition for 926 site years across a wide array of ecosystems. The SynFlux dataset will promote further applications to ecosystem, air quality, or climate modeling across the geoscience community.
Matthew N. Hayek, Marcos Longo, Jin Wu, Marielle N. Smith, Natalia Restrepo-Coupe, Raphael Tapajós, Rodrigo da Silva, David R. Fitzjarrald, Plinio B. Camargo, Lucy R. Hutyra, Luciana F. Alves, Bruce Daube, J. William Munger, Kenia T. Wiedemann, Scott R. Saleska, and Steven C. Wofsy
Biogeosciences, 15, 4833–4848, https://doi.org/10.5194/bg-15-4833-2018, https://doi.org/10.5194/bg-15-4833-2018, 2018
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We investigated the roles that weather and forest disturbances like drought play in shaping changes in ecosystem photosynthesis and carbon exchange in an Amazon forest. We discovered that weather largely influenced differences between years, but a prior drought, which occurred 3 years before measurements started, likely hampered photosynthesis in the first year. This is the first atmospheric evidence that drought can have legacy impacts on Amazon forest photosynthesis.
Sarah A. Strode, Junhua Liu, Leslie Lait, Róisín Commane, Bruce Daube, Steven Wofsy, Austin Conaty, Paul Newman, and Michael Prather
Atmos. Chem. Phys., 18, 10955–10971, https://doi.org/10.5194/acp-18-10955-2018, https://doi.org/10.5194/acp-18-10955-2018, 2018
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The GEOS-5 atmospheric model provided forecasts for the Atmospheric Tomography Mission (ATom). GEOS-5 shows skill in simulating the carbon monoxide (CO) measured in ATom-1. African fires contribute to high CO over the tropical Atlantic, but non-fire sources are the main contributors elsewhere. ATom aims to provide a chemical climatology, so we consider whether ATom-1 occurred during a typical summer month. Satellite observations suggest ATom-1 occurred in a clean but not exceptional month.
Mary E. Whelan, Sinikka T. Lennartz, Teresa E. Gimeno, Richard Wehr, Georg Wohlfahrt, Yuting Wang, Linda M. J. Kooijmans, Timothy W. Hilton, Sauveur Belviso, Philippe Peylin, Róisín Commane, Wu Sun, Huilin Chen, Le Kuai, Ivan Mammarella, Kadmiel Maseyk, Max Berkelhammer, King-Fai Li, Dan Yakir, Andrew Zumkehr, Yoko Katayama, Jérôme Ogée, Felix M. Spielmann, Florian Kitz, Bharat Rastogi, Jürgen Kesselmeier, Julia Marshall, Kukka-Maaria Erkkilä, Lisa Wingate, Laura K. Meredith, Wei He, Rüdiger Bunk, Thomas Launois, Timo Vesala, Johan A. Schmidt, Cédric G. Fichot, Ulli Seibt, Scott Saleska, Eric S. Saltzman, Stephen A. Montzka, Joseph A. Berry, and J. Elliott Campbell
Biogeosciences, 15, 3625–3657, https://doi.org/10.5194/bg-15-3625-2018, https://doi.org/10.5194/bg-15-3625-2018, 2018
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Measurements of the trace gas carbonyl sulfide (OCS) are helpful in quantifying photosynthesis at previously unknowable temporal and spatial scales. While CO2 is both consumed and produced within ecosystems, OCS is mostly produced in the oceans or from specific industries, and destroyed in plant leaves in proportion to CO2. This review summarizes the advancements we have made in the understanding of OCS exchange and applications to vital ecosystem water and carbon cycle questions.
Roland Baatz, Pamela L. Sullivan, Li Li, Samantha R. Weintraub, Henry W. Loescher, Michael Mirtl, Peter M. Groffman, Diana H. Wall, Michael Young, Tim White, Hang Wen, Steffen Zacharias, Ingolf Kühn, Jianwu Tang, Jérôme Gaillardet, Isabelle Braud, Alejandro N. Flores, Praveen Kumar, Henry Lin, Teamrat Ghezzehei, Julia Jones, Henry L. Gholz, Harry Vereecken, and Kris Van Looy
Earth Syst. Dynam., 9, 593–609, https://doi.org/10.5194/esd-9-593-2018, https://doi.org/10.5194/esd-9-593-2018, 2018
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Focusing on the usage of integrated models and in situ Earth observatory networks, three challenges are identified to advance understanding of ESD, in particular to strengthen links between biotic and abiotic, and above- and below-ground processes. We propose developing a model platform for interdisciplinary usage, to formalize current network infrastructure based on complementarities and operational synergies, and to extend the reanalysis concept to the ecosystem and critical zone.
Sean Hartery, Róisín Commane, Jakob Lindaas, Colm Sweeney, John Henderson, Marikate Mountain, Nicholas Steiner, Kyle McDonald, Steven J. Dinardo, Charles E. Miller, Steven C. Wofsy, and Rachel Y.-W. Chang
Atmos. Chem. Phys., 18, 185–202, https://doi.org/10.5194/acp-18-185-2018, https://doi.org/10.5194/acp-18-185-2018, 2018
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Methane is the second most important greenhouse gas but its emissions from northern regions are still poorly constrained. This study uses aircraft measurements of methane from Alaska to estimate surface emissions. We found that methane emission rates depend on the soil temperature at depths where its production was taking place, and that total emissions were similar between tundra and boreal regions. These results provide a simple way to predict methane emissions in this region.
Dan Lu, Daniel Ricciuto, Anthony Walker, Cosmin Safta, and William Munger
Biogeosciences, 14, 4295–4314, https://doi.org/10.5194/bg-14-4295-2017, https://doi.org/10.5194/bg-14-4295-2017, 2017
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Calibration of terrestrial ecosystem models (TEMs) is important but challenging. This study applies an advanced sampling technique for parameter estimation of a TEM. The results improve the model fit and predictive performance.
Richard Wehr, Róisín Commane, J. William Munger, J. Barry McManus, David D. Nelson, Mark S. Zahniser, Scott R. Saleska, and Steven C. Wofsy
Biogeosciences, 14, 389–401, https://doi.org/10.5194/bg-14-389-2017, https://doi.org/10.5194/bg-14-389-2017, 2017
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Leaf stomata influence both photosynthesis and transpiration, coupling the carbon and water cycles, but there is no direct method for estimating stomatal behavior on the ecosystem scale. We use the ecosystem–atmosphere exchange of water, heat, and carbonyl sulfide to estimate canopy-integrated stomatal conductance by two independent methods. We then use that conductance to show that the seasonal dynamics of transpiration and evaporation are different than represented in current biosphere models.
Kirsti Ashworth, Serena H. Chung, Karena A. McKinney, Ying Liu, J. William Munger, Scot T. Martin, and Allison L. Steiner
Atmos. Chem. Phys., 16, 15461–15484, https://doi.org/10.5194/acp-16-15461-2016, https://doi.org/10.5194/acp-16-15461-2016, 2016
Kaniska Mallick, Ivonne Trebs, Eva Boegh, Laura Giustarini, Martin Schlerf, Darren T. Drewry, Lucien Hoffmann, Celso von Randow, Bart Kruijt, Alessandro Araùjo, Scott Saleska, James R. Ehleringer, Tomas F. Domingues, Jean Pierre H. B. Ometto, Antonio D. Nobre, Osvaldo Luiz Leal de Moraes, Matthew Hayek, J. William Munger, and Steven C. Wofsy
Hydrol. Earth Syst. Sci., 20, 4237–4264, https://doi.org/10.5194/hess-20-4237-2016, https://doi.org/10.5194/hess-20-4237-2016, 2016
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While quantifying vegetation water use over multiple plant function types in the Amazon Basin, we found substantial biophysical control during drought as well as a water-stress period and dominant climatic control during a water surplus period. This work has direct implication in understanding the resilience of the Amazon forest in the spectre of frequent drought menace as well as the role of drought-induced plant biophysical functioning in modulating the water-carbon coupling in this ecosystem.
Xiyan Xu, William J. Riley, Charles D. Koven, Dave P. Billesbach, Rachel Y.-W. Chang, Róisín Commane, Eugénie S. Euskirchen, Sean Hartery, Yoshinobu Harazono, Hiroki Iwata, Kyle C. McDonald, Charles E. Miller, Walter C. Oechel, Benjamin Poulter, Naama Raz-Yaseef, Colm Sweeney, Margaret Torn, Steven C. Wofsy, Zhen Zhang, and Donatella Zona
Biogeosciences, 13, 5043–5056, https://doi.org/10.5194/bg-13-5043-2016, https://doi.org/10.5194/bg-13-5043-2016, 2016
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Wetlands are the largest global natural methane source. Peat-rich bogs and fens lying between 50°N and 70°N contribute 10–30% to this source. The predictive capability of the seasonal methane cycle can directly affect the estimation of global methane budget. We present multiscale methane seasonal emission by observations and modeling and find that the uncertainties in predicting the seasonal methane emissions are from the wetland extent, cold-season CH4 production and CH4 transport processes.
Christian Frankenberg, Susan S. Kulawik, Steven C. Wofsy, Frédéric Chevallier, Bruce Daube, Eric A. Kort, Christopher O'Dell, Edward T. Olsen, and Gregory Osterman
Atmos. Chem. Phys., 16, 7867–7878, https://doi.org/10.5194/acp-16-7867-2016, https://doi.org/10.5194/acp-16-7867-2016, 2016
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We use observations from the HIAPER Pole-to-Pole Observations (HIPPO) flights from January 2009 through September 2011 to validate CO2 measurements from satellites (GOSAT, TES, AIRS) and atmospheric inversion models (CarbonTracker CT2013B, MACC v13r1).
Anna Karion, Colm Sweeney, John B. Miller, Arlyn E. Andrews, Roisin Commane, Steven Dinardo, John M. Henderson, Jacob Lindaas, John C. Lin, Kristina A. Luus, Tim Newberger, Pieter Tans, Steven C. Wofsy, Sonja Wolter, and Charles E. Miller
Atmos. Chem. Phys., 16, 5383–5398, https://doi.org/10.5194/acp-16-5383-2016, https://doi.org/10.5194/acp-16-5383-2016, 2016
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Northern high-latitude carbon sources and sinks, including those resulting from degrading permafrost, are thought to be sensitive to the rapidly warming climate. Here we use carbon dioxide and methane measurements from a tower near Fairbanks AK to investigate regional Alaskan fluxes of CO2 and CH4 for 2012–2014.
Scot M. Miller, Roisin Commane, Joe R. Melton, Arlyn E. Andrews, Joshua Benmergui, Edward J. Dlugokencky, Greet Janssens-Maenhout, Anna M. Michalak, Colm Sweeney, and Doug E. J. Worthy
Biogeosciences, 13, 1329–1339, https://doi.org/10.5194/bg-13-1329-2016, https://doi.org/10.5194/bg-13-1329-2016, 2016
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We use atmospheric data from the US and Canada to examine seven wetland methane flux estimates. Relative to existing estimates, we find a methane source that is smaller in magnitude with a broader seasonal cycle. Furthermore, we estimate the largest fluxes over the Hudson Bay Lowlands, a spatial distribution that differs from commonly used remote sensing estimates of wetland location.
F. Deng, D. B. A. Jones, T. W. Walker, M. Keller, K. W. Bowman, D. K. Henze, R. Nassar, E. A. Kort, S. C. Wofsy, K. A. Walker, A. E. Bourassa, and D. A. Degenstein
Atmos. Chem. Phys., 15, 11773–11788, https://doi.org/10.5194/acp-15-11773-2015, https://doi.org/10.5194/acp-15-11773-2015, 2015
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The upper troposphere and lower stratosphere (UTLS) is characterized by strong gradients in the distribution of long-lived tracers, which are sensitive to discrepancies in transport in models. We found that our model overestimates CO2 in the polar UTLS through comparison of modeled CO2 with aircraft observations. We then corrected the modeled CO2 and quantified the impact of the correction on the flux estimates using an atmospheric model together with atmospheric CO2 measured from a satellite.
K. C. Wells, D. B. Millet, N. Bousserez, D. K. Henze, S. Chaliyakunnel, T. J. Griffis, Y. Luan, E. J. Dlugokencky, R. G. Prinn, S. O'Doherty, R. F. Weiss, G. S. Dutton, J. W. Elkins, P. B. Krummel, R. Langenfelds, L. P. Steele, E. A. Kort, S. C. Wofsy, and T. Umezawa
Geosci. Model Dev., 8, 3179–3198, https://doi.org/10.5194/gmd-8-3179-2015, https://doi.org/10.5194/gmd-8-3179-2015, 2015
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This paper introduces a new inversion framework for N2O using GEOS-Chem and its adjoint, which we employed in a series of observing system simulation experiments to evaluate the source and sink constraints provided by surface and aircraft-based N2O measurements. We also applied a new approach for estimating a posteriori uncertainty for high-dimensional inversions, and used it to quantify the spatial and temporal resolution of N2O emission constraints achieved with the current observing network.
L. Molina, G. Broquet, P. Imbach, F. Chevallier, B. Poulter, D. Bonal, B. Burban, M. Ramonet, L. V. Gatti, S. C. Wofsy, J. W. Munger, E. Dlugokencky, and P. Ciais
Atmos. Chem. Phys., 15, 8423–8438, https://doi.org/10.5194/acp-15-8423-2015, https://doi.org/10.5194/acp-15-8423-2015, 2015
Z. Y. Wu, L. Zhang, X. M. Wang, and J. W. Munger
Atmos. Chem. Phys., 15, 7487–7496, https://doi.org/10.5194/acp-15-7487-2015, https://doi.org/10.5194/acp-15-7487-2015, 2015
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In this study, we have developed a modified micrometeorological gradient method (MGM), although based on existing micrometeorological theory, to estimate O3 dry deposition fluxes over a forest canopy using concentration gradients between a level above and a level below the canopy top. The new method provides an alternative approach in monitoring/estimating long-term deposition fluxes of similar pollutants over tall canopies and is expected to be useful for the scientific community.
G. Wohlfahrt, C. Amelynck, C. Ammann, A. Arneth, I. Bamberger, A. H. Goldstein, L. Gu, A. Guenther, A. Hansel, B. Heinesch, T. Holst, L. Hörtnagl, T. Karl, Q. Laffineur, A. Neftel, K. McKinney, J. W. Munger, S. G. Pallardy, G. W. Schade, R. Seco, and N. Schoon
Atmos. Chem. Phys., 15, 7413–7427, https://doi.org/10.5194/acp-15-7413-2015, https://doi.org/10.5194/acp-15-7413-2015, 2015
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Methanol is the second most abundant volatile organic compound in the troposphere and plays a significant role in atmospheric chemistry. While there is consensus about the dominant role of plants as the major source and the reaction with OH as the major sink, global methanol budgets diverge considerably in terms of source/sink estimates. Here we present micrometeorological methanol flux data from eight sites in order to provide a first cross-site synthesis of the terrestrial methanol exchange.
J. M. Henderson, J. Eluszkiewicz, M. E. Mountain, T. Nehrkorn, R. Y.-W. Chang, A. Karion, J. B. Miller, C. Sweeney, N. Steiner, S. C. Wofsy, and C. E. Miller
Atmos. Chem. Phys., 15, 4093–4116, https://doi.org/10.5194/acp-15-4093-2015, https://doi.org/10.5194/acp-15-4093-2015, 2015
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This paper describes the atmospheric modeling that underlies the science analysis for the NASA Carbon in Arctic Reservoirs Vulnerability Experiment (CARVE). Summary statistics of the WRF meteorological model performance on a 3.3 km grid indicate good overall agreement with surface and radiosonde observations. The high quality of the WRF meteorological fields inspires confidence in their use to drive the STILT transport model for the purpose of computing surface influence fields (“footprints”).
M. J. Alvarado, V. H. Payne, K. E. Cady-Pereira, J. D. Hegarty, S. S. Kulawik, K. J. Wecht, J. R. Worden, J. V. Pittman, and S. C. Wofsy
Atmos. Meas. Tech., 8, 965–985, https://doi.org/10.5194/amt-8-965-2015, https://doi.org/10.5194/amt-8-965-2015, 2015
M. M. Bela, K. M. Longo, S. R. Freitas, D. S. Moreira, V. Beck, S. C. Wofsy, C. Gerbig, K. Wiedemann, M. O. Andreae, and P. Artaxo
Atmos. Chem. Phys., 15, 757–782, https://doi.org/10.5194/acp-15-757-2015, https://doi.org/10.5194/acp-15-757-2015, 2015
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In the Amazon Basin, gases that lead to the formation of ozone (O3), an air pollutant and greenhouse gas, are emitted from fire, urban and biogenic sources. This study presents the first basin wide aircraft measurements of O3 during the dry-to-wet and wet-to-dry transition seasons, which show extremely low values above undisturbed forest and increases from fires. This work also demonstrates the capabilities and limitations of regional atmospheric chemistry models in representing O3 in Amazonia.
M. Alexe, P. Bergamaschi, A. Segers, R. Detmers, A. Butz, O. Hasekamp, S. Guerlet, R. Parker, H. Boesch, C. Frankenberg, R. A. Scheepmaker, E. Dlugokencky, C. Sweeney, S. C. Wofsy, and E. A. Kort
Atmos. Chem. Phys., 15, 113–133, https://doi.org/10.5194/acp-15-113-2015, https://doi.org/10.5194/acp-15-113-2015, 2015
B. Xiang, D. D. Nelson, J. B. McManus, M. S. Zahniser, R. A. Wehr, and S. C. Wofsy
Atmos. Meas. Tech., 7, 4445–4453, https://doi.org/10.5194/amt-7-4445-2014, https://doi.org/10.5194/amt-7-4445-2014, 2014
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We designed and built a spectrometer, ABsolute Carbon dioxide (ABC), to measure atmospheric concentration of carbon dioxide. This instrument was tested in a forest environment for almost a year. Based on results from this long-term field deployment, we proved that ABC has the capability of performing high-accuracy, unattended, continuous field measurements with minimal use of reference gas cylinders.
M. N. Deeter, S. Martínez-Alonso, D. P. Edwards, L. K. Emmons, J. C. Gille, H. M. Worden, C. Sweeney, J. V. Pittman, B. C. Daube, and S. C. Wofsy
Atmos. Meas. Tech., 7, 3623–3632, https://doi.org/10.5194/amt-7-3623-2014, https://doi.org/10.5194/amt-7-3623-2014, 2014
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The MOPITT Version 6 product for carbon monoxide (CO) incorporates several enhancements. First, a geolocation bias has been eliminated. Second, the new variable a priori for CO concentrations is based on simulations performed with the CAM-Chem chemical transport model for the years 2000-2009. Third, required meteorological fields are extracted from the MERRA reanalysis. Finally, a retrieval bias in the upper troposphere was substantially reduced. Validation results are presented.
S. O'Doherty, M. Rigby, J. Mühle, D. J. Ivy, B. R. Miller, D. Young, P. G. Simmonds, S. Reimann, M. K. Vollmer, P. B. Krummel, P. J. Fraser, L. P. Steele, B. Dunse, P. K. Salameh, C. M. Harth, T. Arnold, R. F. Weiss, J. Kim, S. Park, S. Li, C. Lunder, O. Hermansen, N. Schmidbauer, L. X. Zhou, B. Yao, R. H. J. Wang, A. J. Manning, and R. G. Prinn
Atmos. Chem. Phys., 14, 9249–9258, https://doi.org/10.5194/acp-14-9249-2014, https://doi.org/10.5194/acp-14-9249-2014, 2014
K. J. Wecht, D. J. Jacob, M. P. Sulprizio, G. W. Santoni, S. C. Wofsy, R. Parker, H. Bösch, and J. Worden
Atmos. Chem. Phys., 14, 8173–8184, https://doi.org/10.5194/acp-14-8173-2014, https://doi.org/10.5194/acp-14-8173-2014, 2014
H. Zheng, H. Huang, L. Yao, J. Liu, H. He, and J. Tang
Biogeosciences, 11, 3685–3693, https://doi.org/10.5194/bg-11-3685-2014, https://doi.org/10.5194/bg-11-3685-2014, 2014
R. L. Thompson, K. Ishijima, E. Saikawa, M. Corazza, U. Karstens, P. K. Patra, P. Bergamaschi, F. Chevallier, E. Dlugokencky, R. G. Prinn, R. F. Weiss, S. O'Doherty, P. J. Fraser, L. P. Steele, P. B. Krummel, A. Vermeulen, Y. Tohjima, A. Jordan, L. Haszpra, M. Steinbacher, S. Van der Laan, T. Aalto, F. Meinhardt, M. E. Popa, J. Moncrieff, and P. Bousquet
Atmos. Chem. Phys., 14, 6177–6194, https://doi.org/10.5194/acp-14-6177-2014, https://doi.org/10.5194/acp-14-6177-2014, 2014
G. W. Santoni, B. C. Daube, E. A. Kort, R. Jiménez, S. Park, J. V. Pittman, E. Gottlieb, B. Xiang, M. S. Zahniser, D. D. Nelson, J. B. McManus, J. Peischl, T. B. Ryerson, J. S. Holloway, A. E. Andrews, C. Sweeney, B. Hall, E. J. Hintsa, F. L. Moore, J. W. Elkins, D. F. Hurst, B. B. Stephens, J. Bent, and S. C. Wofsy
Atmos. Meas. Tech., 7, 1509–1526, https://doi.org/10.5194/amt-7-1509-2014, https://doi.org/10.5194/amt-7-1509-2014, 2014
R. L. Thompson, P. K. Patra, K. Ishijima, E. Saikawa, M. Corazza, U. Karstens, C. Wilson, P. Bergamaschi, E. Dlugokencky, C. Sweeney, R. G. Prinn, R. F. Weiss, S. O'Doherty, P. J. Fraser, L. P. Steele, P. B. Krummel, M. Saunois, M. Chipperfield, and P. Bousquet
Atmos. Chem. Phys., 14, 4349–4368, https://doi.org/10.5194/acp-14-4349-2014, https://doi.org/10.5194/acp-14-4349-2014, 2014
A. L. Ganesan, M. Rigby, A. Zammit-Mangion, A. J. Manning, R. G. Prinn, P. J. Fraser, C. M. Harth, K.-R. Kim, P. B. Krummel, S. Li, J. Mühle, S. J. O'Doherty, S. Park, P. K. Salameh, L. P. Steele, and R. F. Weiss
Atmos. Chem. Phys., 14, 3855–3864, https://doi.org/10.5194/acp-14-3855-2014, https://doi.org/10.5194/acp-14-3855-2014, 2014
F. Deng, D. B. A. Jones, D. K. Henze, N. Bousserez, K. W. Bowman, J. B. Fisher, R. Nassar, C. O'Dell, D. Wunch, P. O. Wennberg, E. A. Kort, S. C. Wofsy, T. Blumenstock, N. M. Deutscher, D. W. T. Griffith, F. Hase, P. Heikkinen, V. Sherlock, K. Strong, R. Sussmann, and T. Warneke
Atmos. Chem. Phys., 14, 3703–3727, https://doi.org/10.5194/acp-14-3703-2014, https://doi.org/10.5194/acp-14-3703-2014, 2014
A. E. Andrews, J. D. Kofler, M. E. Trudeau, J. C. Williams, D. H. Neff, K. A. Masarie, D. Y. Chao, D. R. Kitzis, P. C. Novelli, C. L. Zhao, E. J. Dlugokencky, P. M. Lang, M. J. Crotwell, M. L. Fischer, M. J. Parker, J. T. Lee, D. D. Baumann, A. R. Desai, C. O. Stanier, S. F. J. De Wekker, D. E. Wolfe, J. W. Munger, and P. P. Tans
Atmos. Meas. Tech., 7, 647–687, https://doi.org/10.5194/amt-7-647-2014, https://doi.org/10.5194/amt-7-647-2014, 2014
P. C. Stoy, M. C. Dietze, A. D. Richardson, R. Vargas, A. G. Barr, R. S. Anderson, M. A. Arain, I. T. Baker, T. A. Black, J. M. Chen, R. B. Cook, C. M. Gough, R. F. Grant, D. Y. Hollinger, R. C. Izaurralde, C. J. Kucharik, P. Lafleur, B. E. Law, S. Liu, E. Lokupitiya, Y. Luo, J. W. Munger, C. Peng, B. Poulter, D. T. Price, D. M. Ricciuto, W. J. Riley, A. K. Sahoo, K. Schaefer, C. R. Schwalm, H. Tian, H. Verbeeck, and E. Weng
Biogeosciences, 10, 6893–6909, https://doi.org/10.5194/bg-10-6893-2013, https://doi.org/10.5194/bg-10-6893-2013, 2013
A. L. Ganesan, A. Chatterjee, R. G. Prinn, C. M. Harth, P. K. Salameh, A. J. Manning, B. D. Hall, J. Mühle, L. K. Meredith, R. F. Weiss, S. O'Doherty, and D. Young
Atmos. Chem. Phys., 13, 10633–10644, https://doi.org/10.5194/acp-13-10633-2013, https://doi.org/10.5194/acp-13-10633-2013, 2013
X. Xiong, C. Barnet, E. S. Maddy, A. Gambacorta, T. S. King, and S. C. Wofsy
Atmos. Meas. Tech., 6, 2255–2265, https://doi.org/10.5194/amt-6-2255-2013, https://doi.org/10.5194/amt-6-2255-2013, 2013
B. Xiang, D. D. Nelson, J. B. McManus, M. S. Zahniser, and S. C. Wofsy
Atmos. Meas. Tech., 6, 1611–1621, https://doi.org/10.5194/amt-6-1611-2013, https://doi.org/10.5194/amt-6-1611-2013, 2013
J. Brioude, W. M. Angevine, R. Ahmadov, S.-W. Kim, S. Evan, S. A. McKeen, E.-Y. Hsie, G. J. Frost, J. A. Neuman, I. B. Pollack, J. Peischl, T. B. Ryerson, J. Holloway, S. S. Brown, J. B. Nowak, J. M. Roberts, S. C. Wofsy, G. W. Santoni, T. Oda, and M. Trainer
Atmos. Chem. Phys., 13, 3661–3677, https://doi.org/10.5194/acp-13-3661-2013, https://doi.org/10.5194/acp-13-3661-2013, 2013
Related subject area
Subject: Gases | Technique: In Situ Measurement | Topic: Validation and Intercomparisons
Improving consistency in methane emission quantification from the natural gas distribution systems across measurement devices
Interpretation of mass spectra by a Vocus proton-transfer-reaction mass spectrometer (PTR-MS) at an urban site: insights from gas chromatographic pre-separation
Improving the quantification of peak concentrations for air quality sensors via data weighting
Long-term observations of atmospheric CO2 and CH4 trends and comparison of two measurement systems at Pallas-Sammaltunturi station in Northern Finland
Evaluating mass flow meter measurements from chambers for greenhouse gas emission from orphan wells and other point sources
An evaluation of airborne mass balance and tracer correlation approaches to estimate site-level CH4 emissions from LNG facilities using CO2 as a tracer of opportunity
Calibrating adsorptive and reactive losses of monoterpenes and sesquiterpenes in dynamic chambers using deuterated surrogates
Orphaned Oil & Gas Well Methane Emission Rates Quantified with Gaussian Plume Inversions of Ambient Observations
OF–CEAS laser spectroscopy to measure water isotopes in dry environments: example of application in Antarctica
Performance evaluation of air quality sensors for environmental epidemiology
Towards a high-quality in situ observation network for oxygenated volatile organic compounds (OVOCs) in Europe: transferring metrological traceability to the field
Intercomparison of IAGOS-CORE, IAGOS-CARIBIC and WMO/GAW-WCCOS Ozone Instruments at the Environmental Simulation Facility at Jülich, Germany
Validation of formaldehyde products from three satellite retrievals (OMI SAO, OMPS-NPP SAO, and OMI BIRA) in the marine atmosphere with four seasons of Atmospheric Tomography Mission (ATom) aircraft observations
Methodology and uncertainty estimation for measurements of methane leakage in a manufactured house
Evaluating Weather and Chemical Transport Models at High Latitudes using MAGIC2021 Airborne Measurements
Alternate materials for the capture and quantification of gaseous oxidized mercury in the atmosphere
Lower-cost eddy covariance for CO2 and H2O fluxes over grassland and agroforestry
Evaluation of optimized flux chamber design for measurement of ammonia emission after field application of slurry with full-scale farm machinery
Preparation of low-concentration H2 test gas mixtures in ambient air for calibration of H2 sensors
Pico-Light H2O: intercomparison of in situ water vapour measurements during the AsA 2022 campaign
Mobile air quality monitoring and comparison to fixed monitoring sites for instrument performance assessment
Intercomparison of eddy-covariance software for urban tall-tower sites
Assessment of current methane emission quantification techniques for natural gas midstream applications
Performance assessment of state-of-the-art and novel methods for remote compliance monitoring of sulfur emissions from shipping
Intercomparison of detection and quantification methods for methane emissions from the natural gas distribution network in Hamburg, Germany
Comparison of photoacoustic spectroscopy and cavity ring-down spectroscopy for ambient methane monitoring at Hohenpeißenberg
Comparison of atmospheric CO, CO2 and CH4 measurements at the Schneefernerhaus and the mountain ridge at Zugspitze
Intercomparison of commercial analyzers for atmospheric ethane and methane observations
Real-time measurement of phase partitioning of organic compounds using a proton-transfer-reaction time-of-flight mass spectrometer coupled to a CHARON inlet
A quantitative comparison of methods used to measure smaller methane emissions typically observed from superannuated oil and gas infrastructure
Comparing airborne algorithms for greenhouse gas flux measurements over the Alberta oil sands
Characterization of inexpensive metal oxide sensor performance for trace methane detection
Intercomparison of upper tropospheric and lower stratospheric water vapor measurements over the Asian Summer Monsoon during the StratoClim campaign
Air pollution measurement errors: is your data fit for purpose?
Performance characterization of low-cost air quality sensors for off-grid deployment in rural Malawi
Comment on “Comparison of ozone measurement methods in biomass burning smoke: an evaluation under field and laboratory conditions” by Long et al. (2021)
Homogenization of the Observatoire de Haute Provence electrochemical concentration cell (ECC) ozonesonde data record: comparison with lidar and satellite observations
Long-term behavior and stability of calibration models for NO and NO2 low-cost sensors
Controlled-release experiment to investigate uncertainties in UAV-based emission quantification for methane point sources
Ozone formation sensitivity study using machine learning coupled with the reactivity of volatile organic compound species
Evaluating uncertainty in sensor networks for urban air pollution insights
Estimating oil sands emissions using horizontal path-integrated column measurements
Global evaluation of the precipitable-water-vapor product from MERSI-II (Medium Resolution Spectral Imager) on board the Fengyun-3D satellite
Field testing two flux footprint models
Validation of a new cavity ring-down spectrometer for measuring tropospheric gaseous hydrogen chloride
Comparison of formaldehyde measurements by Hantzsch, CRDS and DOAS in the SAPHIR chamber
A field intercomparison of three passive air samplers for gaseous mercury in ambient air
Beef cattle methane emissions measured with tracer-ratio and inverse dispersion modelling techniques
Methane emissions from an oil sands tailings pond: a quantitative comparison of fluxes derived by different methods
Performance of open-path GasFinder3 devices for CH4 concentration measurements close to ambient levels
Judith Tettenborn, Daniel Zavala-Araiza, Daan Stroeken, Hossein Maazallahi, Carina van der Veen, Arjan Hensen, Ilona Velzeboer, Pim van den Bulk, Felix Vogel, Lawson Gillespie, Sebastien Ars, James France, David Lowry, Rebecca Fisher, and Thomas Röckmann
Atmos. Meas. Tech., 18, 3569–3584, https://doi.org/10.5194/amt-18-3569-2025, https://doi.org/10.5194/amt-18-3569-2025, 2025
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Measurements of methane with vehicle-based sensors are an effective method to identify and quantify leaks from urban gas distribution systems. We deliberately released methane in different environments and calibrated the response of different methane analysers when they transected the plumes in a vehicle. We derived an improved statistical function for consistent emission estimations using different instruments. Repeated transects reduce the uncertainty in emission rate estimates.
Ying Zhang, Yuwei Wang, Chuang Li, Yueyang Li, Sijia Yin, Megan S. Claflin, Brian M. Lerner, Douglas Worsnop, and Lin Wang
Atmos. Meas. Tech., 18, 3547–3568, https://doi.org/10.5194/amt-18-3547-2025, https://doi.org/10.5194/amt-18-3547-2025, 2025
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This study provides insight into how individual ions measured by proton-transfer-reaction (PTR) mass spectrometry are produced by multiple volatile organic compounds (VOCs). A reference table is provided for attributing the PTR signal to contributing VOC species. The signals are grouped according to the complexity of their potential identities. We find that a number of signal ions such as C6H7+ for benzene and C5H9+ for isoprene merely give an upper limit of their corresponding concentrations.
Caroline Frischmon, Jonathan Silberstein, Annamarie Guth, Erick Mattson, Jack Porter, and Michael Hannigan
Atmos. Meas. Tech., 18, 3147–3159, https://doi.org/10.5194/amt-18-3147-2025, https://doi.org/10.5194/amt-18-3147-2025, 2025
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Air quality sensors often underpredict peak concentrations, which is a major issue in applications such as emission event detection. Here, we detail a novel approach involving data weighting to improve quantification of these peak values. To demonstrate its effectiveness, we applied data weighting to carbon monoxide, methane, and volatile organic compound sensor data. This work broadens our ability to use air sensors in contexts where accurate quantification of peak concentrations is essential.
Antti Laitinen, Hermanni Aaltonen, Christoph Zellweger, Aki Tsuruta, Tuula Aalto, and Juha Hatakka
Atmos. Meas. Tech., 18, 3109–3133, https://doi.org/10.5194/amt-18-3109-2025, https://doi.org/10.5194/amt-18-3109-2025, 2025
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This paper presents long-term observations of atmospheric CO2 and CH4 mole fractions and a comparison of two permanent and two mobile measurement systems located in Northern Finland. Furthermore, the observed mole fractions are compared against the mean marine boundary layer product for the Northern Hemisphere. The comparisons of all the systems show good agreement in relation to the World Meteorological Organization/Global Atmosphere Watch network compatibility goal limits for CO2 and CH4.
Karl B. Haase and Nicholas J. Gianoutsos
EGUsphere, https://doi.org/10.5194/egusphere-2025-1201, https://doi.org/10.5194/egusphere-2025-1201, 2025
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This work demonstrates a simple approach for using mass flow meters connected to rigid chambers for measuring gas emissions rates in situations the meter cannot be attached directly, such as orphan oil and gas wells. This paper shows the results of performance testing, demonstrates common sources of uncertainty, and provides suggestions for how to use the approach to generate the best quality data. The findings can be used by researchers, the petroleum industry, regulators, and carbon markets.
Mark F. Lunt, Stephen J. Harris, Jorg Hacker, Ian Joynes, Tim Robertson, Simon Thompson, and James L. France
EGUsphere, https://doi.org/10.5194/egusphere-2025-1926, https://doi.org/10.5194/egusphere-2025-1926, 2025
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To ensure robust use of measurement-based approaches to estimate methane emissions from individual sites, it is important to validate the accuracy of the methods used in the field. By using co-emitted carbon dioxide, we evaluate the performance of one such quantification method at liquefied natural gas terminals. We further demonstrate the potential for a more efficient quantification approach by considering the ratio of methane to carbon dioxide concentrations.
Jianqiang Zeng, Yanli Zhang, Haofan Ran, Weihua Pang, Hao Guo, Zhaobin Mu, Wei Song, and Xinming Wang
Atmos. Meas. Tech., 18, 1811–1821, https://doi.org/10.5194/amt-18-1811-2025, https://doi.org/10.5194/amt-18-1811-2025, 2025
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This study revealed the existence of significant species-specific adsorptive and reactive losses of monoterpenes and sesquiterpenes in dynamic chambers. The deuterated α-pinene-d3 and β-caryophyllene-d2 were proven as effective surrogates in tracing these losses for some key monoterpenes and sesquiterpenes. The findings highlight the importance of selecting internal surrogates that closely match the adsorptive and reactive behaviors of target compounds for precise loss correction.
Emily Follansbee, James E. Lee, Mohit L. Dubey, Jonathan F. Dooley, Curtis Shuck, Ken Minschwaner, Andre Santos, Sebastien C. Biraud, and Manvendra K. Dubey
EGUsphere, https://doi.org/10.5194/egusphere-2025-344, https://doi.org/10.5194/egusphere-2025-344, 2025
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This work uses ambient methane and wind measurements to quantify methane emissions from a leaking orphaned oil and gas well using Gaussian plume inversions. Our analysis shows that existing Gaussian plume methods that assume atmospheric stability are prone to large errors. We report a more robust analysis that determines plume dispersion coefficients from our in situ observations. Our technique enables more accurate methane quantification of orphaned oil and gas wells to prioritize plugging.
Thomas Lauwers, Elise Fourré, Olivier Jossoud, Daniele Romanini, Frédéric Prié, Giordano Nitti, Mathieu Casado, Kévin Jaulin, Markus Miltner, Morgane Farradèche, Valérie Masson-Delmotte, and Amaëlle Landais
Atmos. Meas. Tech., 18, 1135–1147, https://doi.org/10.5194/amt-18-1135-2025, https://doi.org/10.5194/amt-18-1135-2025, 2025
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Water vapour isotopes are important tools to better understand processes governing the atmospheric hydrological cycle. In polar regions, their measurement helps to improve the interpretation of water isotopic records in ice cores. However, in situ water vapour isotopic monitoring is an important challenge, especially in dry places of East Antarctica. We present here an alternative laser spectroscopy technique adapted for such measurements, with a limit of detection down to 10 ppm humidity.
Miriam Chacón-Mateos, Héctor García-Salamero, Bernd Laquai, and Ulrich Vogt
EGUsphere, https://doi.org/10.5194/egusphere-2025-587, https://doi.org/10.5194/egusphere-2025-587, 2025
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This study evaluates air quality sensors in indoor & outdoor environments to support health research. Sensors were calibrated using data from reference instruments, and regression and machine learning models were tested for data correction. Results highlight the importance of using high-quality training data during co-location. Integrating metadata, such as activity logs, helps validate calibrated sensor data. These findings can enhance the use of air quality sensors in health studies globally.
Maitane Iturrate-Garcia, Thérèse Salameh, Paul Schlauri, Annarita Baldan, Martin K. Vollmer, Evdokia Stratigou, Sebastien Dusanter, Jianrong Li, Stefan Persijn, Anja Claude, Rupert Holzinger, Christophe Sutour, Tatiana Macé, Yasin Elshorbany, Andreas Ackermann, Céline Pascale, and Stefan Reimann
Atmos. Meas. Tech., 18, 371–403, https://doi.org/10.5194/amt-18-371-2025, https://doi.org/10.5194/amt-18-371-2025, 2025
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Accurate and comparable measurements of oxygenated organic compounds (OVOCs) are crucial in assessing tropospheric ozone burdens and trends. However, the monitoring of many OVOCs remains challenging because of their low atmospheric abundance and lack of stable and traceable calibration standards. This paper describes the calibration standards developed for OVOCs at a low amount of substance fractions (<100 nmol mol-1) to transfer traceability of the International System of Units to the field.
Herman G.J. Smit, Torben Galle, Romain Blot, Florian Obersteiner, Philippe Nédélec, Andreas Zahn, Jean-Marc Cousin, Ulrich Bundke, Andreas Petzold, Valerie Thouret, and Hannah Clark
EGUsphere, https://doi.org/10.5194/egusphere-2024-3760, https://doi.org/10.5194/egusphere-2024-3760, 2025
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The two ozone instruments of IAGOS (In-service Aircraft for a Global Observation System) have been compared with the Ozone PhotoMeter (OPM) of the World Calibration Center of Ozone Sondes (WCCOS) in an atmospheric simulation chamber under realistic flight conditions of pressure, temperature, and ozone concentrations. The two IAGOS-instruments showed good agreement with the OPM within 5–6 %. The observed differences are small but systematic and reproducible during the intercomparison.
Jin Liao, Glenn M. Wolfe, Alexander E. Kotsakis, Julie M. Nicely, Jason M. St. Clair, Thomas F. Hanisco, Gonzalo González Abad, Caroline R. Nowlan, Zolal Ayazpour, Isabelle De Smedt, Eric C. Apel, and Rebecca S. Hornbrook
Atmos. Meas. Tech., 18, 1–16, https://doi.org/10.5194/amt-18-1-2025, https://doi.org/10.5194/amt-18-1-2025, 2025
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Validation of satellite HCHO over the remote marine regions is relatively low, and modeled HCHO in these regions is usually added as a global satellite HCHO background. This paper intercompares three satellite HCHO retrievals and validates them against in situ observations from the NASA ATom mission. All retrievals are correlated with ATom-integrated columns over remote oceans, with OMI SAO (v004) showing the best agreement. A persistent low bias is found in all retrievals at high latitudes.
Anna Karion, Michael F. Link, Rileigh Robertson, Tyler Boyle, and Dustin Poppendieck
Atmos. Meas. Tech., 17, 7065–7075, https://doi.org/10.5194/amt-17-7065-2024, https://doi.org/10.5194/amt-17-7065-2024, 2024
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Methane leaks into houses that use natural gas from appliances, pipes, and fittings. We measured methane emitted from a manufactured house under different ventilation conditions using indoor and outdoor concentration measurements. We injected methane at prescribed rates into the house and then measured the emissions using our method. We report the error in the calculation based on these tests. We also describe the method and provide guidance on conducting this type of experiment.
Félix Langot, Cyril Crevoisier, Thomas Lauvaux, Charbel Abdallah, Jérôme Pernin, Xin Lin, Marielle Saunois, Axel Guedj, Thomas Ponthieu, Anke Roiger, Klaus-Dirk Gottschaldt, and Alina Fiehn
EGUsphere, https://doi.org/10.5194/egusphere-2024-3559, https://doi.org/10.5194/egusphere-2024-3559, 2024
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Our study compares outputs from meteorological and atmospheric composition models to data from the MAGIC2021 campaign that took place in Sweden. Our results highlight performance differences among models, revealing strengths and weaknesses of different modelling techniques. We also found that wetland emission inventories overestimated emissions in regional simulations. This work helps refining methane emission predictions, essential for understanding climate change.
Livia Lown, Sarrah M. Dunham-Cheatham, Seth N. Lyman, and Mae S. Gustin
Atmos. Meas. Tech., 17, 6397–6413, https://doi.org/10.5194/amt-17-6397-2024, https://doi.org/10.5194/amt-17-6397-2024, 2024
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New sorbent materials are needed to preconcentrate atmospheric oxidized mercury for analysis by developing mass spectrometry methods. Chitosan, α-Al2O3, and γ-Al2O3 were tested for quantitative gaseous oxidized mercury sorption in ambient air under laboratory and field conditions. Although these materials sorbed gaseous oxidized mercury without sorbing elemental mercury in the laboratory, less oxidized mercury was recovered from these materials compared to cation exchange membranes in the field.
Justus G. V. van Ramshorst, Alexander Knohl, José Ángel Callejas-Rodelas, Robert Clement, Timothy C. Hill, Lukas Siebicke, and Christian Markwitz
Atmos. Meas. Tech., 17, 6047–6071, https://doi.org/10.5194/amt-17-6047-2024, https://doi.org/10.5194/amt-17-6047-2024, 2024
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In this work we present experimental field results of a lower-cost eddy covariance (LC-EC) system, which can measure the ecosystem exchange of carbon dioxide and water vapour with the atmosphere. During three field campaigns on a grassland and agroforestry grassland, we compared the LC-EC with a conventional eddy covariance (CON-EC) system. Our results show that LC-EC has the potential to measure EC fluxes at only approximately 25 % of the cost of a CON-EC system.
Johanna Pedersen, Sasha D. Hafner, Andreas Pacholski, Valthor I. Karlsson, Li Rong, Rodrigo Labouriau, and Jesper N. Kamp
Atmos. Meas. Tech., 17, 4493–4505, https://doi.org/10.5194/amt-17-4493-2024, https://doi.org/10.5194/amt-17-4493-2024, 2024
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Field-applied animal slurry is a significant source of NH3 emission. A new system of dynamic flux chambers for NH3 measurements was developed and validated using three field trials in order to assess the variability after application with a trailing hose at different scales: manual (handheld) application, a 3 m slurry boom, and a 30 m slurry boom. The system facilitates NH3 emission measurement with replication after both manual and farm-scale slurry application with relatively high precision.
Niklas Karbach, Lisa Höhler, Peter Hoor, Heiko Bozem, Nicole Bobrowski, and Thorsten Hoffmann
Atmos. Meas. Tech., 17, 4081–4086, https://doi.org/10.5194/amt-17-4081-2024, https://doi.org/10.5194/amt-17-4081-2024, 2024
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The system presented here can accurately generate and reproduce a stable flow of gas mixtures of known concentrations over several days using ambient air as a dilution medium. In combination with the small size and low weight of the system, this enables the calibration of hydrogen sensors in the field, reducing the influence of matrix effects on the accuracy of the sensor. The system is inexpensive to assemble and easy to maintain, which is the key to reliable measurement results.
Mélanie Ghysels, Georges Durry, Nadir Amarouche, Dale Hurst, Emrys Hall, Kensy Xiong, Jean-Charles Dupont, Jean-Christophe Samake, Fabien Frérot, Raghed Bejjani, and Emmanuel D. Riviere
Atmos. Meas. Tech., 17, 3495–3513, https://doi.org/10.5194/amt-17-3495-2024, https://doi.org/10.5194/amt-17-3495-2024, 2024
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A tunable diode laser hygrometer, “Pico-Light H2O”, is presented and its performances are evaluated during the AsA 2022 balloon-borne intercomparison campaign from Aire-sur-l'Adour (France) in September 2022. A total of 15 balloons were launched within the framework of the EU-funded HEMERA project. Pico-Light H2O has been compared in situ with the NOAA Frost Point Hygrometer in the upper troposphere and stratosphere, as well as with meteorological sondes (iMet-4 and M20) in the troposphere.
Andrew R. Whitehill, Melissa Lunden, Brian LaFranchi, Surender Kaushik, and Paul A. Solomon
Atmos. Meas. Tech., 17, 2991–3009, https://doi.org/10.5194/amt-17-2991-2024, https://doi.org/10.5194/amt-17-2991-2024, 2024
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We present an analysis from two large-scale mobile air quality monitoring campaigns in Colorado and California. We compare mobile measurements of air quality to measurements from nearby regulatory sites. The goal of this paper is to explore how fixed-site measurements (such as regulatory site measurements) can be used for ongoing instrument performance assessment of mobile monitoring platforms over extended measurement campaigns.
Changxing Lan, Matthias Mauder, Stavros Stagakis, Benjamin Loubet, Claudio D'Onofrio, Stefan Metzger, David Durden, and Pedro-Henrique Herig-Coimbra
Atmos. Meas. Tech., 17, 2649–2669, https://doi.org/10.5194/amt-17-2649-2024, https://doi.org/10.5194/amt-17-2649-2024, 2024
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Using eddy-covariance systems deployed in three cities, we aimed to elucidate the sources of discrepancies in flux estimations from different software packages. One crucial finding is the impact of low-frequency spectral loss corrections on tall-tower flux estimations. Our findings emphasize the significance of a standardized measurement setup and consistent postprocessing configurations in minimizing the systematic flux uncertainty resulting from the usage of different software packages.
Yunsong Liu, Jean-Daniel Paris, Gregoire Broquet, Violeta Bescós Roy, Tania Meixus Fernandez, Rasmus Andersen, Andrés Russu Berlanga, Emil Christensen, Yann Courtois, Sebastian Dominok, Corentin Dussenne, Travis Eckert, Andrew Finlayson, Aurora Fernández de la Fuente, Catlin Gunn, Ram Hashmonay, Juliano Grigoleto Hayashi, Jonathan Helmore, Soeren Honsel, Fabrizio Innocenti, Matti Irjala, Torgrim Log, Cristina Lopez, Francisco Cortés Martínez, Jonathan Martinez, Adrien Massardier, Helle Gottschalk Nygaard, Paula Agregan Reboredo, Elodie Rousset, Axel Scherello, Matthias Ulbricht, Damien Weidmann, Oliver Williams, Nigel Yarrow, Murès Zarea, Robert Ziegler, Jean Sciare, Mihalis Vrekoussis, and Philippe Bousquet
Atmos. Meas. Tech., 17, 1633–1649, https://doi.org/10.5194/amt-17-1633-2024, https://doi.org/10.5194/amt-17-1633-2024, 2024
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We investigated the performance of 10 methane emission quantification techniques in a blind controlled-release experiment at an inerted natural gas compressor station. We reported their respective strengths, weaknesses, and potential complementarity depending on the emission rates and atmospheric conditions. Additionally, we assess the dependence of emission quantification performance on key parameters such as wind speed, deployment constraints, and measurement duration.
Jörg Beecken, Andreas Weigelt, Simone Griesel, Johan Mellqvist, Alexander V. Conde Jacobo, Daniëlle van Dinther, Jan Duyzer, Jon Knudsen, Bettina Knudsen, and Leonidas Ntziachristos
Atmos. Meas. Tech., 16, 5883–5895, https://doi.org/10.5194/amt-16-5883-2023, https://doi.org/10.5194/amt-16-5883-2023, 2023
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Air pollution from shipping is a debated topic in science and politics. We compare different monitoring systems currently used in different European countries for the enforcement of emission limits regarding air pollution from ships according to regulation. The system performances were individually assessed in the field by comparison with true values. Non-compliant vessels with actual fuel sulfur contents > 0.15–0.19 % Sm/m can be detected by the compared systems with 95 % confidence.
Hossein Maazallahi, Antonio Delre, Charlotte Scheutz, Anders M. Fredenslund, Stefan Schwietzke, Hugo Denier van der Gon, and Thomas Röckmann
Atmos. Meas. Tech., 16, 5051–5073, https://doi.org/10.5194/amt-16-5051-2023, https://doi.org/10.5194/amt-16-5051-2023, 2023
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Measurement methods are increasingly deployed to verify reported methane emissions of gas leaks. This study describes unique advantages and limitations of three methods. Two methods are rapidly deployed, but uncertainties and biases exist for some leak locations. In contrast, the suction method could accurately determine leak rates in principle. However, this method, which provides data for the German emission inventory, creates an overall low bias in our study due to non-random site selection.
Max Müller, Stefan Weigl, Jennifer Müller-Williams, Matthias Lindauer, Thomas Rück, Simon Jobst, Rudolf Bierl, and Frank-Michael Matysik
Atmos. Meas. Tech., 16, 4263–4270, https://doi.org/10.5194/amt-16-4263-2023, https://doi.org/10.5194/amt-16-4263-2023, 2023
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Over a period of 5 d, a photoacoustic methane sensor was compared with a Picarro cavity ring-down (G2301) spectrometer. Both devices measured the ambient methane concentration at the meteorological observatory Hohenpeißenberg. Cross-sensitivities on the photoacoustic signal, due to fluctuating ambient humidity, were compensated by applying the CoNRad algorithm. The results show that photoacoustic sensors have the potential for accurate and precise greenhouse gas monitoring.
Antje Hoheisel, Cedric Couret, Bryan Hellack, and Martina Schmidt
Atmos. Meas. Tech., 16, 2399–2413, https://doi.org/10.5194/amt-16-2399-2023, https://doi.org/10.5194/amt-16-2399-2023, 2023
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High-precision CO2, CH4 and CO measurements have been carried out at Zugspitze for decades. New technologies make it possible to analyse these gases with high temporal resolution. This allows the detection of local pollution. To this end, measurements have been performed on the mountain ridge (ZGR) and are compared to routine measurements at the Schneefernerhaus (ZSF). Careful manual flagging of pollution events in the ZSF data leads to consistency with the little influenced ZGR time series.
Róisín Commane, Andrew Hallward-Driemeier, and Lee T. Murray
Atmos. Meas. Tech., 16, 1431–1441, https://doi.org/10.5194/amt-16-1431-2023, https://doi.org/10.5194/amt-16-1431-2023, 2023
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Methane / ethane ratios can be used to identify and partition the different sources of methane, especially in areas with natural gas mixed with biogenic methane emissions, such as cities. We tested three commercially available laser-based analyzers for sensitivity, precision, size, power requirement, ease of use on mobile platforms, and expertise needed to operate the instrument, and we make recommendations for use in various situations.
Yarong Peng, Hongli Wang, Yaqin Gao, Shengao Jing, Shuhui Zhu, Dandan Huang, Peizhi Hao, Shengrong Lou, Tiantao Cheng, Cheng Huang, and Xuan Zhang
Atmos. Meas. Tech., 16, 15–28, https://doi.org/10.5194/amt-16-15-2023, https://doi.org/10.5194/amt-16-15-2023, 2023
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This work examined the phase partitioning behaviors of organic compounds at hourly resolution in ambient conditions with the use of the CHemical Analysis of aeRosols ONline (CHARON) inlet coupled to a proton-transfer-reaction time-of-flight mass spectrometer (PTR-ToF-MS). Properly accounting for the neutral losses of small moieties during the molecular feature extraction from PTR mass spectra could significantly reduce uncertainties associated with the gas–particle partitioning measurements.
Stuart N. Riddick, Riley Ancona, Mercy Mbua, Clay S. Bell, Aidan Duggan, Timothy L. Vaughn, Kristine Bennett, and Daniel J. Zimmerle
Atmos. Meas. Tech., 15, 6285–6296, https://doi.org/10.5194/amt-15-6285-2022, https://doi.org/10.5194/amt-15-6285-2022, 2022
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This describes controlled release experiments at the METEC facility in Fort Collins, USA, that investigates the accuracy and precision of five methods commonly used to measure methane emissions. Methods include static/dynamic chambers, hi flow sampling, a backward Lagrangian stochastic method, and a Gaussian plume method. This is the first time that methods for measuring CH4 emissions from point sources less than 200 g CH4 h−1 have been quantitively assessed against references and each other.
Broghan M. Erland, Cristen Adams, Andrea Darlington, Mackenzie L. Smith, Andrew K. Thorpe, Gregory R. Wentworth, Steve Conley, John Liggio, Shao-Meng Li, Charles E. Miller, and John A. Gamon
Atmos. Meas. Tech., 15, 5841–5859, https://doi.org/10.5194/amt-15-5841-2022, https://doi.org/10.5194/amt-15-5841-2022, 2022
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Accurately estimating greenhouse gas (GHG) emissions is essential to reaching net-zero goals to combat the climate crisis. Airborne box-flights are ideal for assessing regional GHG emissions, as they can attain small error. We compare two box-flight algorithms and found they produce similar results, but daily variability must be considered when deriving emissions inventories. Increasing the consistency and agreement between airborne methods moves us closer to achieving more accurate estimates.
Daniel Furuta, Tofigh Sayahi, Jinsheng Li, Bruce Wilson, Albert A. Presto, and Jiayu Li
Atmos. Meas. Tech., 15, 5117–5128, https://doi.org/10.5194/amt-15-5117-2022, https://doi.org/10.5194/amt-15-5117-2022, 2022
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Methane is a major greenhouse gas and contributor to climate change with various human-caused and natural sources. Currently, atmospheric methane is expensive to sense. We investigate repurposing cheap methane safety sensors for atmospheric sensing, finding several promising sensors and identifying some of the challenges in this approach. This work will help in developing inexpensive sensor networks for methane monitoring, which will aid in reducing methane leaks and emissions.
Clare E. Singer, Benjamin W. Clouser, Sergey M. Khaykin, Martina Krämer, Francesco Cairo, Thomas Peter, Alexey Lykov, Christian Rolf, Nicole Spelten, Armin Afchine, Simone Brunamonti, and Elisabeth J. Moyer
Atmos. Meas. Tech., 15, 4767–4783, https://doi.org/10.5194/amt-15-4767-2022, https://doi.org/10.5194/amt-15-4767-2022, 2022
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In situ measurements of water vapor in the upper troposphere are necessary to study cloud formation and hydration of the stratosphere but challenging due to cold–dry conditions. We compare measurements from three water vapor instruments from the StratoClim campaign in 2017. In clear sky (clouds), point-by-point differences were <1.5±8 % (<1±8 %). This excellent agreement allows detection of fine-scale structures required to understand the impact of convection on stratospheric water vapor.
Sebastian Diez, Stuart E. Lacy, Thomas J. Bannan, Michael Flynn, Tom Gardiner, David Harrison, Nicholas Marsden, Nicholas A. Martin, Katie Read, and Pete M. Edwards
Atmos. Meas. Tech., 15, 4091–4105, https://doi.org/10.5194/amt-15-4091-2022, https://doi.org/10.5194/amt-15-4091-2022, 2022
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Regardless of the cost of the measuring instrument, there are no perfect measurements. For this reason, we compare the quality of the information provided by cheap devices when they are used to measure air pollutants and we try to emphasise that before judging the potential usefulness of the devices, the user must specify his own needs. Since commonly used performance indices/metrics can be misleading in qualifying this, we propose complementary visual analysis to the more commonly used metrics.
Ashley S. Bittner, Eben S. Cross, David H. Hagan, Carl Malings, Eric Lipsky, and Andrew P. Grieshop
Atmos. Meas. Tech., 15, 3353–3376, https://doi.org/10.5194/amt-15-3353-2022, https://doi.org/10.5194/amt-15-3353-2022, 2022
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We present findings from a 1-year pilot deployment of low-cost integrated air quality sensor packages in rural Malawi using calibration models developed during collocation with US regulatory monitors. We compare the results with data from remote sensing products and previous field studies. We conclude that while the remote calibration approach can help extract useful data, great care is needed when assessing low-cost sensor data collected in regions without reference instrumentation.
Noah Bernays, Daniel A. Jaffe, Irina Petropavlovskikh, and Peter Effertz
Atmos. Meas. Tech., 15, 3189–3192, https://doi.org/10.5194/amt-15-3189-2022, https://doi.org/10.5194/amt-15-3189-2022, 2022
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Ozone is an important pollutant that impacts millions of people worldwide. It is therefore important to ensure accurate measurements. A recent surge in wildfire activity in the USA has resulted in significant enhancements in ozone concentration. However given the nature of wildfire smoke, there are questions about our ability to accurately measure ozone. In this comment, we discuss possible biases in the UV measurements of ozone in the presence of smoke.
Gérard Ancellet, Sophie Godin-Beekmann, Herman G. J. Smit, Ryan M. Stauffer, Roeland Van Malderen, Renaud Bodichon, and Andrea Pazmiño
Atmos. Meas. Tech., 15, 3105–3120, https://doi.org/10.5194/amt-15-3105-2022, https://doi.org/10.5194/amt-15-3105-2022, 2022
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The 1991–2021 Observatoire de Haute Provence electrochemical concentration cell (ECC) ozonesonde data have been homogenized according to the recommendations of the Ozonesonde Data Quality Assessment panel. Comparisons with ground-based instruments also measuring ozone at the same station (lidar, surface measurements) and with colocated satellite observations show the benefits of this homogenization. Remaining differences between ECC and other observations in the stratosphere are also discussed.
Horim Kim, Michael Müller, Stephan Henne, and Christoph Hüglin
Atmos. Meas. Tech., 15, 2979–2992, https://doi.org/10.5194/amt-15-2979-2022, https://doi.org/10.5194/amt-15-2979-2022, 2022
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In this study, the performance of electrochemical sensors for NO and NO2 for measuring air quality was determined over a longer operating period. The performance of NO sensors remained reliable for more than 18 months. However, the NO2 sensors showed decreasing performance over time. During deployment, we found that the NO2 sensors can distinguish general pollution levels, but they proved unsuitable for accurate measurements due to significant biases.
Randulph Morales, Jonas Ravelid, Katarina Vinkovic, Piotr Korbeń, Béla Tuzson, Lukas Emmenegger, Huilin Chen, Martina Schmidt, Sebastian Humbel, and Dominik Brunner
Atmos. Meas. Tech., 15, 2177–2198, https://doi.org/10.5194/amt-15-2177-2022, https://doi.org/10.5194/amt-15-2177-2022, 2022
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Mapping trace gas emission plumes using in situ measurements from unmanned aerial vehicles (UAVs) is an emerging and attractive possibility to quantify emissions from localized sources. We performed an extensive controlled-release experiment to develop an optimal quantification method and to determine the related uncertainties under various environmental and sampling conditions. Our approach was successful in quantifying local methane sources from drone-based measurements.
Junlei Zhan, Yongchun Liu, Wei Ma, Xin Zhang, Xuezhong Wang, Fang Bi, Yujie Zhang, Zhenhai Wu, and Hong Li
Atmos. Meas. Tech., 15, 1511–1520, https://doi.org/10.5194/amt-15-1511-2022, https://doi.org/10.5194/amt-15-1511-2022, 2022
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Our study investigated the O3 formation sensitivity in Beijing using a random forest model coupled with the reactivity of volatile organic
compound (VOC) species. Results found that random forest accurately predicted O3 concentration when initial VOCs were considered, and relative importance correlated well with O3 formation potential. The O3 isopleth curves calculated by the random forest model were generally comparable with those calculated by the box model.
Daniel R. Peters, Olalekan A. M. Popoola, Roderic L. Jones, Nicholas A. Martin, Jim Mills, Elizabeth R. Fonseca, Amy Stidworthy, Ella Forsyth, David Carruthers, Megan Dupuy-Todd, Felicia Douglas, Katie Moore, Rishabh U. Shah, Lauren E. Padilla, and Ramón A. Alvarez
Atmos. Meas. Tech., 15, 321–334, https://doi.org/10.5194/amt-15-321-2022, https://doi.org/10.5194/amt-15-321-2022, 2022
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We present more than 2 years of NO2 pollution measurements from a sensor network in Greater London and compare results to an extensive network of expensive reference-grade monitors. We show the ability of our lower-cost network to generate robust insights about local air pollution. We also show how irregularities in sensor performance lead to some uncertainty in results and demonstrate ways that future users can characterize and mitigate uncertainties to get the most value from sensor data.
Timothy G. Pernini, T. Scott Zaccheo, Jeremy Dobler, and Nathan Blume
Atmos. Meas. Tech., 15, 225–240, https://doi.org/10.5194/amt-15-225-2022, https://doi.org/10.5194/amt-15-225-2022, 2022
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We demonstrate a novel approach to estimating emissions from oil sands operations that utilizes the GreenLITE™ gas concentration measurement system and an atmospheric model. While deployed at a facility in the Athabasca region of Alberta, Canada, CH4 emissions from a tailings pond were estimated to be 7.2 t/d for July–October 2019, and 5.1 t/d for March–July 2020. CH4 emissions from an open-pit mine were estimated to be 24.6 t/d for September–October 2019.
Wengang Zhang, Ling Wang, Yang Yu, Guirong Xu, Xiuqing Hu, Zhikang Fu, and Chunguang Cui
Atmos. Meas. Tech., 14, 7821–7834, https://doi.org/10.5194/amt-14-7821-2021, https://doi.org/10.5194/amt-14-7821-2021, 2021
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Global precipitable water vapor (PWV) derived from MERSI-II (Medium Resolution Spectral Imager) is compared with PWV from the Integrated Global Radiosonde Archive (IGRA). Our results show a good agreement between PWV from MERSI-II and IGRA and that MERSI-II PWV is slightly underestimated on the whole, especially in summer. The bias between MERSI-II and IGRA grows with a larger spatial distance between the footprint of the satellite and the IGRA station, as well as increasing PWV.
Trevor W. Coates, Monzurul Alam, Thomas K. Flesch, and Guillermo Hernandez-Ramirez
Atmos. Meas. Tech., 14, 7147–7152, https://doi.org/10.5194/amt-14-7147-2021, https://doi.org/10.5194/amt-14-7147-2021, 2021
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A field study tested two footprint models for calculating surface emissions from downwind flux measurements. Emission rates from a 10 × 10 m synthetic source were estimated with the simple Kormann–Meixner model and a sophisticated Lagrangian stochastic model. Both models underestimated emissions by approximately 30 %, and no statistical differences were observed between the models. Footprint models are critically important for interpreting eddy covariance measurements.
Teles C. Furlani, Patrick R. Veres, Kathryn E. R. Dawe, J. Andrew Neuman, Steven S. Brown, Trevor C. VandenBoer, and Cora J. Young
Atmos. Meas. Tech., 14, 5859–5871, https://doi.org/10.5194/amt-14-5859-2021, https://doi.org/10.5194/amt-14-5859-2021, 2021
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This study characterized and validated a commercial spectroscopic instrument for the measurement of hydrogen chloride (HCl) in the atmosphere. Near the Earth’s surface, HCl acts as the dominant reservoir for other chlorine-containing reactive chemicals that play an important role in atmospheric chemistry. The properties of HCl make it challenging to measure. This instrument can overcome many of these challenges, enabling reliable HCl measurements.
Marvin Glowania, Franz Rohrer, Hans-Peter Dorn, Andreas Hofzumahaus, Frank Holland, Astrid Kiendler-Scharr, Andreas Wahner, and Hendrik Fuchs
Atmos. Meas. Tech., 14, 4239–4253, https://doi.org/10.5194/amt-14-4239-2021, https://doi.org/10.5194/amt-14-4239-2021, 2021
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Three instruments that use different techniques to measure gaseous formaldehyde concentrations were compared in experiments in the atmospheric simulation chamber SAPHIR at Forschungszentrum Jülich. The results demonstrated the need to correct the baseline in measurements by instruments that use the Hantzsch reaction or make use of cavity ring-down spectroscopy. After applying corrections, all three methods gave accurate and precise measurements within their specifications.
Attilio Naccarato, Antonella Tassone, Maria Martino, Sacha Moretti, Antonella Macagnano, Emiliano Zampetti, Paolo Papa, Joshua Avossa, Nicola Pirrone, Michelle Nerentorp, John Munthe, Ingvar Wängberg, Geoff W. Stupple, Carl P. J. Mitchell, Adam R. Martin, Alexandra Steffen, Diana Babi, Eric M. Prestbo, Francesca Sprovieri, and Frank Wania
Atmos. Meas. Tech., 14, 3657–3672, https://doi.org/10.5194/amt-14-3657-2021, https://doi.org/10.5194/amt-14-3657-2021, 2021
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Mercury monitoring in support of the Minamata Convention requires effective and reliable analytical tools. Passive sampling is a promising approach for creating a sustainable long-term network for atmospheric mercury with improved spatial resolution and global coverage. In this study the analytical performance of three passive air samplers (CNR-PAS, IVL-PAS, and MerPAS) was assessed over extended deployment periods and the accuracy of concentrations was judged by comparison with active sampling.
Mei Bai, José I. Velazco, Trevor W. Coates, Frances A. Phillips, Thomas K. Flesch, Julian Hill, David G. Mayer, Nigel W. Tomkins, Roger S. Hegarty, and Deli Chen
Atmos. Meas. Tech., 14, 3469–3479, https://doi.org/10.5194/amt-14-3469-2021, https://doi.org/10.5194/amt-14-3469-2021, 2021
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The development and validation of management practices to mitigate methane (CH4) emissions from livestock require accurate emission measurements. We compared the inverse dispersion modelling (IDM) and tracer-ratio techniques to measure CH4 emissions from cattle. Both measurements agreed well but were higher than IPCC estimates. We suggest that the IDM approach can provide an accurate method of estimating cattle emissions, and IPCC estimates may have larger uncertainties.
Yuan You, Ralf M. Staebler, Samar G. Moussa, James Beck, and Richard L. Mittermeier
Atmos. Meas. Tech., 14, 1879–1892, https://doi.org/10.5194/amt-14-1879-2021, https://doi.org/10.5194/amt-14-1879-2021, 2021
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Tailings ponds in the Alberta oil sands can be significant sources of methane, an important greenhouse gas. This paper describes a 1-month study conducted in 2017 to measure methane emissions from a pond using a variety of micrometeorological flux methods and demonstrates some advantages of these methods over flux chambers.
Christoph Häni, Marcel Bühler, Albrecht Neftel, Christof Ammann, and Thomas Kupper
Atmos. Meas. Tech., 14, 1733–1741, https://doi.org/10.5194/amt-14-1733-2021, https://doi.org/10.5194/amt-14-1733-2021, 2021
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