Articles | Volume 16, issue 6
https://doi.org/10.5194/amt-16-1551-2023
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/amt-16-1551-2023
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
24 Mar 2023
Research article |
| 24 Mar 2023
| 24 Mar 2023
Short-term variability of atmospheric helium revealed through a cryo-enrichment method
Scripps Institution of Oceanography, University of California San Diego, La Jolla, CA 92037, USA
Eric Morgan
Scripps Institution of Oceanography, University of California San Diego, La Jolla, CA 92037, USA
Ralph F. Keeling
Scripps Institution of Oceanography, University of California San Diego, La Jolla, CA 92037, USA
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The atmospheric helium-to-nitrogen ratio is a promising indicator for circulation changes in the upper atmosphere and fossil fuel burning by humans. We present a very precise analysis method to determine changes in the helium-to-nitrogen ratio of air samples. The method relies on stabilizing the gas flow to a mass spectrometer and continuous removal of reactive gases. These advances enable new insights and monitoring possibilities for anthropogenic and natural processes.
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Ancient air enclosed in bubbles of the Antarctic ice sheet is a key source of information about the Earth's past climate. However, a range of physical processes in the snow layer atop an ice sheet may change the trapped air's chemical composition before it is occluded in the ice. We developed the first detailed 2-D computer simulation of these processes and found a new method to improve the reconstruction of past climate from air in ice cores bubbles.
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Christian Rödenbeck, Tim DeVries, Judith Hauck, Corinne Le Quéré, and Ralph F. Keeling
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Nobuyuki Aoki, Shigeyuki Ishidoya, Yasunori Tohjima, Shinji Morimoto, Ralph F. Keeling, Adam Cox, Shuichiro Takebayashi, and Shohei Murayama
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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
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Britton B. Stephens, Eric J. Morgan, Jonathan D. Bent, Ralph F. Keeling, Andrew S. Watt, Stephen R. Shertz, and Bruce C. Daube
Atmos. Meas. Tech., 14, 2543–2574, https://doi.org/10.5194/amt-14-2543-2021, https://doi.org/10.5194/amt-14-2543-2021, 2021
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We describe methods used to make high-precision global-scale airborne measurements of atmospheric oxygen concentrations over a period of 20 years in order to study the global carbon cycle. Our techniques include an in situ vacuum ultraviolet absorption instrument and a pressure- and flow-controlled, cryogenically dried, glass flask sampler. We have deployed these instruments in 15 airborne research campaigns spanning from the Earth’s surface to the lower stratosphere and from pole to pole.
Benjamin Birner, William Paplawsky, Jeffrey Severinghaus, and Ralph F. Keeling
Atmos. Meas. Tech., 14, 2515–2527, https://doi.org/10.5194/amt-14-2515-2021, https://doi.org/10.5194/amt-14-2515-2021, 2021
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The atmospheric helium-to-nitrogen ratio is a promising indicator for circulation changes in the upper atmosphere and fossil fuel burning by humans. We present a very precise analysis method to determine changes in the helium-to-nitrogen ratio of air samples. The method relies on stabilizing the gas flow to a mass spectrometer and continuous removal of reactive gases. These advances enable new insights and monitoring possibilities for anthropogenic and natural processes.
Yuming Jin, Ralph F. Keeling, Eric J. Morgan, Eric Ray, Nicholas C. Parazoo, and Britton B. Stephens
Atmos. Chem. Phys., 21, 217–238, https://doi.org/10.5194/acp-21-217-2021, https://doi.org/10.5194/acp-21-217-2021, 2021
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We propose a new atmospheric coordinate (Mθe) based on equivalent potential temperature (θe) but with mass as the unit. This coordinate is useful in studying the spatial and temporal distribution of long-lived chemical tracers (CO2, CH4, O2 / N2, etc.) from sparse data, like airborne observation. Using this coordinate and sparse airborne observation (HIPPO and ATom), we resolve the Northern Hemisphere mass-weighted average CO2 seasonal cycle with high accuracy.
Benjamin Birner, Martyn P. Chipperfield, Eric J. Morgan, Britton B. Stephens, Marianna Linz, Wuhu Feng, Chris Wilson, Jonathan D. Bent, Steven C. Wofsy, Jeffrey Severinghaus, and Ralph F. Keeling
Atmos. Chem. Phys., 20, 12391–12408, https://doi.org/10.5194/acp-20-12391-2020, https://doi.org/10.5194/acp-20-12391-2020, 2020
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With new high-precision observations from nine aircraft campaigns and 3-D chemical transport modeling, we show that the argon-to-nitrogen ratio (Ar / N2) in the lowermost stratosphere provides a useful constraint on the “age of air” (the time elapsed since entry of an air parcel into the stratosphere). Therefore, Ar / N2 in combination with traditional age-of-air indicators, such as CO2 and N2O, could provide new insights into atmospheric mixing and transport.
Elizabeth Asher, Rebecca S. Hornbrook, Britton B. Stephens, Doug Kinnison, Eric J. Morgan, Ralph F. Keeling, Elliot L. Atlas, Sue M. Schauffler, Simone Tilmes, Eric A. Kort, Martin S. Hoecker-Martínez, Matt C. Long, Jean-François Lamarque, Alfonso Saiz-Lopez, Kathryn McKain, Colm Sweeney, Alan J. Hills, and Eric C. Apel
Atmos. Chem. Phys., 19, 14071–14090, https://doi.org/10.5194/acp-19-14071-2019, https://doi.org/10.5194/acp-19-14071-2019, 2019
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Halogenated organic trace gases, which are a source of reactive halogens to the atmosphere, exert a disproportionately large influence on atmospheric chemistry and climate. This paper reports novel aircraft observations of halogenated compounds over the Southern Ocean in summer and evaluates hypothesized regional sources and emissions of these trace gases through their relationships to additional aircraft observations.
Eric J. Morgan, Jost V. Lavric, Damian L. Arévalo-Martínez, Hermann W. Bange, Tobias Steinhoff, Thomas Seifert, and Martin Heimann
Biogeosciences, 16, 4065–4084, https://doi.org/10.5194/bg-16-4065-2019, https://doi.org/10.5194/bg-16-4065-2019, 2019
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Taking a 2-year atmospheric record of atmospheric oxygen and the greenhouse gases N2O, CO2, and CH4, made at a coastal site in the Namib Desert, we estimated the fluxes of these gases from upwelling events in the northern Benguela Current region. We compared these results with flux measurements made on a research vessel in the study area at the same time and found that the two approaches agreed well. The study region was a source of N2O, CO2, and CH4 to the atmosphere during upwelling events.
Corinne Le Quéré, Robbie M. Andrew, Pierre Friedlingstein, Stephen Sitch, Judith Hauck, Julia Pongratz, Penelope A. Pickers, Jan Ivar Korsbakken, Glen P. Peters, Josep G. Canadell, Almut Arneth, Vivek K. Arora, Leticia Barbero, Ana Bastos, Laurent Bopp, Frédéric Chevallier, Louise P. Chini, Philippe Ciais, Scott C. Doney, Thanos Gkritzalis, Daniel S. Goll, Ian Harris, Vanessa Haverd, Forrest M. Hoffman, Mario Hoppema, Richard A. Houghton, George Hurtt, Tatiana Ilyina, Atul K. Jain, Truls Johannessen, Chris D. Jones, Etsushi Kato, Ralph F. Keeling, Kees Klein Goldewijk, Peter Landschützer, Nathalie Lefèvre, Sebastian Lienert, Zhu Liu, Danica Lombardozzi, Nicolas Metzl, David R. Munro, Julia E. M. S. Nabel, Shin-ichiro Nakaoka, Craig Neill, Are Olsen, Tsueno Ono, Prabir Patra, Anna Peregon, Wouter Peters, Philippe Peylin, Benjamin Pfeil, Denis Pierrot, Benjamin Poulter, Gregor Rehder, Laure Resplandy, Eddy Robertson, Matthias Rocher, Christian Rödenbeck, Ute Schuster, Jörg Schwinger, Roland Séférian, Ingunn Skjelvan, Tobias Steinhoff, Adrienne Sutton, Pieter P. Tans, Hanqin Tian, Bronte Tilbrook, Francesco N. Tubiello, Ingrid T. van der Laan-Luijkx, Guido R. van der Werf, Nicolas Viovy, Anthony P. Walker, Andrew J. Wiltshire, Rebecca Wright, Sönke Zaehle, and Bo Zheng
Earth Syst. Sci. Data, 10, 2141–2194, https://doi.org/10.5194/essd-10-2141-2018, https://doi.org/10.5194/essd-10-2141-2018, 2018
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The Global Carbon Budget 2018 describes the data sets and methodology used to quantify the emissions of carbon dioxide and their partitioning among the atmosphere, land, and ocean. These living data are updated every year to provide the highest transparency and traceability in the reporting of CO2, the key driver of climate change.
Benjamin Birner, Christo Buizert, Till J. W. Wagner, and Jeffrey P. Severinghaus
The Cryosphere, 12, 2021–2037, https://doi.org/10.5194/tc-12-2021-2018, https://doi.org/10.5194/tc-12-2021-2018, 2018
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Ancient air enclosed in bubbles of the Antarctic ice sheet is a key source of information about the Earth's past climate. However, a range of physical processes in the snow layer atop an ice sheet may change the trapped air's chemical composition before it is occluded in the ice. We developed the first detailed 2-D computer simulation of these processes and found a new method to improve the reconstruction of past climate from air in ice cores bubbles.
Christian Rödenbeck, Sönke Zaehle, Ralph Keeling, and Martin Heimann
Biogeosciences, 15, 2481–2498, https://doi.org/10.5194/bg-15-2481-2018, https://doi.org/10.5194/bg-15-2481-2018, 2018
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In this paper we investigate how the CO2 exchange between the land vegetation and the atmosphere varies from year to year. We quantify the relation between variations in the CO2 exchange and variations in air temperature. For this quantification, we use long-term measurements of CO2 in the air at many locations, a simulation code for the transport of carbon dioxide through the atmosphere, and a data set of air temperature. The results help us to understand the mechanisms of CO2 exchange.
Corinne Le Quéré, Robbie M. Andrew, Pierre Friedlingstein, Stephen Sitch, Julia Pongratz, Andrew C. Manning, Jan Ivar Korsbakken, Glen P. Peters, Josep G. Canadell, Robert B. Jackson, Thomas A. Boden, Pieter P. Tans, Oliver D. Andrews, Vivek K. Arora, Dorothee C. E. Bakker, Leticia Barbero, Meike Becker, Richard A. Betts, Laurent Bopp, Frédéric Chevallier, Louise P. Chini, Philippe Ciais, Catherine E. Cosca, Jessica Cross, Kim Currie, Thomas Gasser, Ian Harris, Judith Hauck, Vanessa Haverd, Richard A. Houghton, Christopher W. Hunt, George Hurtt, Tatiana Ilyina, Atul K. Jain, Etsushi Kato, Markus Kautz, Ralph F. Keeling, Kees Klein Goldewijk, Arne Körtzinger, Peter Landschützer, Nathalie Lefèvre, Andrew Lenton, Sebastian Lienert, Ivan Lima, Danica Lombardozzi, Nicolas Metzl, Frank Millero, Pedro M. S. Monteiro, David R. Munro, Julia E. M. S. Nabel, Shin-ichiro Nakaoka, Yukihiro Nojiri, X. Antonio Padin, Anna Peregon, Benjamin Pfeil, Denis Pierrot, Benjamin Poulter, Gregor Rehder, Janet Reimer, Christian Rödenbeck, Jörg Schwinger, Roland Séférian, Ingunn Skjelvan, Benjamin D. Stocker, Hanqin Tian, Bronte Tilbrook, Francesco N. Tubiello, Ingrid T. van der Laan-Luijkx, Guido R. van der Werf, Steven van Heuven, Nicolas Viovy, Nicolas Vuichard, Anthony P. Walker, Andrew J. Watson, Andrew J. Wiltshire, Sönke Zaehle, and Dan Zhu
Earth Syst. Sci. Data, 10, 405–448, https://doi.org/10.5194/essd-10-405-2018, https://doi.org/10.5194/essd-10-405-2018, 2018
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The Global Carbon Budget 2017 describes data sets and methodology to quantify the five major components of the global carbon budget and their uncertainties. It is the 12th annual update and the 6th published in this journal.
Heather Graven, Colin E. Allison, David M. Etheridge, Samuel Hammer, Ralph F. Keeling, Ingeborg Levin, Harro A. J. Meijer, Mauro Rubino, Pieter P. Tans, Cathy M. Trudinger, Bruce H. Vaughn, and James W. C. White
Geosci. Model Dev., 10, 4405–4417, https://doi.org/10.5194/gmd-10-4405-2017, https://doi.org/10.5194/gmd-10-4405-2017, 2017
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Modelling of carbon isotopes 13C and 14C in land and ocean components of Earth system models provides opportunities for new insights and improved understanding of global carbon cycling, and for model evaluation. We compiled existing historical datasets to define the annual mean carbon isotopic composition of atmospheric CO2 for 1850–2015 that can be used in CMIP6 and other modelling activities.
Kristal R. Verhulst, Anna Karion, Jooil Kim, Peter K. Salameh, Ralph F. Keeling, Sally Newman, John Miller, Christopher Sloop, Thomas Pongetti, Preeti Rao, Clare Wong, Francesca M. Hopkins, Vineet Yadav, Ray F. Weiss, Riley M. Duren, and Charles E. Miller
Atmos. Chem. Phys., 17, 8313–8341, https://doi.org/10.5194/acp-17-8313-2017, https://doi.org/10.5194/acp-17-8313-2017, 2017
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We present the first carbon dioxide (CO2) and methane (CH4) measurements from an extensive surface network as part of the Los Angeles Megacity Carbon Project. We describe methods that are essential for understanding carbon fluxes from complex urban environments. CO2 and CH4 levels are spatially and temporally variable, with urban sites showing significant enhancements relative to background. In 2015, the median afternoon enhancement near downtown Los Angeles was ~15 ppm CO2 and ~80 ppb CH4.
Corinne Le Quéré, Robbie M. Andrew, Josep G. Canadell, Stephen Sitch, Jan Ivar Korsbakken, Glen P. Peters, Andrew C. Manning, Thomas A. Boden, Pieter P. Tans, Richard A. Houghton, Ralph F. Keeling, Simone Alin, Oliver D. Andrews, Peter Anthoni, Leticia Barbero, Laurent Bopp, Frédéric Chevallier, Louise P. Chini, Philippe Ciais, Kim Currie, Christine Delire, Scott C. Doney, Pierre Friedlingstein, Thanos Gkritzalis, Ian Harris, Judith Hauck, Vanessa Haverd, Mario Hoppema, Kees Klein Goldewijk, Atul K. Jain, Etsushi Kato, Arne Körtzinger, Peter Landschützer, Nathalie Lefèvre, Andrew Lenton, Sebastian Lienert, Danica Lombardozzi, Joe R. Melton, Nicolas Metzl, Frank Millero, Pedro M. S. Monteiro, David R. Munro, Julia E. M. S. Nabel, Shin-ichiro Nakaoka, Kevin O'Brien, Are Olsen, Abdirahman M. Omar, Tsuneo Ono, Denis Pierrot, Benjamin Poulter, Christian Rödenbeck, Joe Salisbury, Ute Schuster, Jörg Schwinger, Roland Séférian, Ingunn Skjelvan, Benjamin D. Stocker, Adrienne J. Sutton, Taro Takahashi, Hanqin Tian, Bronte Tilbrook, Ingrid T. van der Laan-Luijkx, Guido R. van der Werf, Nicolas Viovy, Anthony P. Walker, Andrew J. Wiltshire, and Sönke Zaehle
Earth Syst. Sci. Data, 8, 605–649, https://doi.org/10.5194/essd-8-605-2016, https://doi.org/10.5194/essd-8-605-2016, 2016
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The Global Carbon Budget 2016 is the 11th annual update of emissions of carbon dioxide (CO2) and their partitioning among the atmosphere, land, and ocean. This data synthesis brings together measurements, statistical information, and analyses of model results in order to provide an assessment of the global carbon budget and their uncertainties for years 1959 to 2015, with a projection for year 2016.
Dorothee C. E. Bakker, Benjamin Pfeil, Camilla S. Landa, Nicolas Metzl, Kevin M. O'Brien, Are Olsen, Karl Smith, Cathy Cosca, Sumiko Harasawa, Stephen D. Jones, Shin-ichiro Nakaoka, Yukihiro Nojiri, Ute Schuster, Tobias Steinhoff, Colm Sweeney, Taro Takahashi, Bronte Tilbrook, Chisato Wada, Rik Wanninkhof, Simone R. Alin, Carlos F. Balestrini, Leticia Barbero, Nicholas R. Bates, Alejandro A. Bianchi, Frédéric Bonou, Jacqueline Boutin, Yann Bozec, Eugene F. Burger, Wei-Jun Cai, Robert D. Castle, Liqi Chen, Melissa Chierici, Kim Currie, Wiley Evans, Charles Featherstone, Richard A. Feely, Agneta Fransson, Catherine Goyet, Naomi Greenwood, Luke Gregor, Steven Hankin, Nick J. Hardman-Mountford, Jérôme Harlay, Judith Hauck, Mario Hoppema, Matthew P. Humphreys, Christopher W. Hunt, Betty Huss, J. Severino P. Ibánhez, Truls Johannessen, Ralph Keeling, Vassilis Kitidis, Arne Körtzinger, Alex Kozyr, Evangelia Krasakopoulou, Akira Kuwata, Peter Landschützer, Siv K. Lauvset, Nathalie Lefèvre, Claire Lo Monaco, Ansley Manke, Jeremy T. Mathis, Liliane Merlivat, Frank J. Millero, Pedro M. S. Monteiro, David R. Munro, Akihiko Murata, Timothy Newberger, Abdirahman M. Omar, Tsuneo Ono, Kristina Paterson, David Pearce, Denis Pierrot, Lisa L. Robbins, Shu Saito, Joe Salisbury, Reiner Schlitzer, Bernd Schneider, Roland Schweitzer, Rainer Sieger, Ingunn Skjelvan, Kevin F. Sullivan, Stewart C. Sutherland, Adrienne J. Sutton, Kazuaki Tadokoro, Maciej Telszewski, Matthias Tuma, Steven M. A. C. van Heuven, Doug Vandemark, Brian Ward, Andrew J. Watson, and Suqing Xu
Earth Syst. Sci. Data, 8, 383–413, https://doi.org/10.5194/essd-8-383-2016, https://doi.org/10.5194/essd-8-383-2016, 2016
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Version 3 of the Surface Ocean CO2 Atlas (www.socat.info) has 14.5 million CO2 (carbon dioxide) values for the years 1957 to 2014 covering the global oceans and coastal seas. Version 3 is an update to version 2 with a longer record and 44 % more CO2 values. The CO2 measurements have been made on ships, fixed moorings and drifting buoys. SOCAT enables quantification of the ocean carbon sink and ocean acidification, as well as model evaluation, thus informing climate negotiations.
Lisa R. Welp, Prabir K. Patra, Christian Rödenbeck, Rama Nemani, Jian Bi, Stephen C. Piper, and Ralph F. Keeling
Atmos. Chem. Phys., 16, 9047–9066, https://doi.org/10.5194/acp-16-9047-2016, https://doi.org/10.5194/acp-16-9047-2016, 2016
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Boreal and arctic ecosystems have been responding to elevated temperatures and atmospheric CO2 over the last decades. It is not clear if these ecosystems are sequestering more carbon or possibly becoming sources. This is an important feedback of the carbon cycle to global warming. We studied monthly biological land CO2 fluxes inferred from atmospheric CO2 concentrations using inverse models and found that net summer CO2 uptake increased, resulting in a small increase in annual CO2 uptake.
Sally Newman, Xiaomei Xu, Kevin R. Gurney, Ying Kuang Hsu, King Fai Li, Xun Jiang, Ralph Keeling, Sha Feng, Darragh O'Keefe, Risa Patarasuk, Kam Weng Wong, Preeti Rao, Marc L. Fischer, and Yuk L. Yung
Atmos. Chem. Phys., 16, 3843–3863, https://doi.org/10.5194/acp-16-3843-2016, https://doi.org/10.5194/acp-16-3843-2016, 2016
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Combining 14C and 13C data from the Los Angeles, CA megacity with background data allows source attribution of CO2 emissions among biosphere, natural gas, and gasoline. The 8-year record of CO2 emissions from fossil fuel burning is consistent with "The Great Recession" of 2008–2010. The long-term trend and source attribution are consistent with government inventories. Seasonal patterns agree with the high-resolution Hestia-LA emission data product, when seasonal wind directions are considered.
C. Le Quéré, R. Moriarty, R. M. Andrew, J. G. Canadell, S. Sitch, J. I. Korsbakken, P. Friedlingstein, G. P. Peters, R. J. Andres, T. A. Boden, R. A. Houghton, J. I. House, R. F. Keeling, P. Tans, A. Arneth, D. C. E. Bakker, L. Barbero, L. Bopp, J. Chang, F. Chevallier, L. P. Chini, P. Ciais, M. Fader, R. A. Feely, T. Gkritzalis, I. Harris, J. Hauck, T. Ilyina, A. K. Jain, E. Kato, V. Kitidis, K. Klein Goldewijk, C. Koven, P. Landschützer, S. K. Lauvset, N. Lefèvre, A. Lenton, I. D. Lima, N. Metzl, F. Millero, D. R. Munro, A. Murata, J. E. M. S. Nabel, S. Nakaoka, Y. Nojiri, K. O'Brien, A. Olsen, T. Ono, F. F. Pérez, B. Pfeil, D. Pierrot, B. Poulter, G. Rehder, C. Rödenbeck, S. Saito, U. Schuster, J. Schwinger, R. Séférian, T. Steinhoff, B. D. Stocker, A. J. Sutton, T. Takahashi, B. Tilbrook, I. T. van der Laan-Luijkx, G. R. van der Werf, S. van Heuven, D. Vandemark, N. Viovy, A. Wiltshire, S. Zaehle, and N. Zeng
Earth Syst. Sci. Data, 7, 349–396, https://doi.org/10.5194/essd-7-349-2015, https://doi.org/10.5194/essd-7-349-2015, 2015
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Accurate assessment of anthropogenic carbon dioxide emissions and their redistribution among the atmosphere, ocean, and terrestrial biosphere is important to understand the global carbon cycle, support the development of climate policies, and project future climate change. We describe data sets and a methodology to quantify all major components of the global carbon budget, including their uncertainties, based on a range of data and models and their interpretation by a broad scientific community.
D. D. Lucas, C. Yver Kwok, P. Cameron-Smith, H. Graven, D. Bergmann, T. P. Guilderson, R. Weiss, and R. Keeling
Geosci. Instrum. Method. Data Syst., 4, 121–137, https://doi.org/10.5194/gi-4-121-2015, https://doi.org/10.5194/gi-4-121-2015, 2015
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Multiobjective optimization is used to design Pareto optimal greenhouse gas (GHG) observing networks. A prototype GHG network is designed to optimize scientific performance and measurement costs. The Pareto frontier is convex, showing the trade-offs between performance and cost and the diminishing returns in trading one for the other. Other objectives and constraints that are important in the design of practical GHG monitoring networks can be incorporated into our method.
E. J. Morgan, J. V. Lavrič, T. Seifert, T. Chicoine, A. Day, J. Gomez, R. Logan, J. Sack, T. Shuuya, E. G. Uushona, K. Vincent, U. Schultz, E.-G. Brunke, C. Labuschagne, R. L. Thompson, S. Schmidt, A. C. Manning, and M. Heimann
Atmos. Meas. Tech., 8, 2233–2250, https://doi.org/10.5194/amt-8-2233-2015, https://doi.org/10.5194/amt-8-2233-2015, 2015
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We describe the analytical techniques used in the creation of a new background site for continuous measurements of greenhouse gases, carbon monoxide, and atmospheric oxygen in the Namib Desert. The measurement system is semi-automated and optimized for operation in a remote locale. Measurement uncertainties, gas handling, calibration schemes, drift corrections, and instrument performance are discussed.
C. Le Quéré, R. Moriarty, R. M. Andrew, G. P. Peters, P. Ciais, P. Friedlingstein, S. D. Jones, S. Sitch, P. Tans, A. Arneth, T. A. Boden, L. Bopp, Y. Bozec, J. G. Canadell, L. P. Chini, F. Chevallier, C. E. Cosca, I. Harris, M. Hoppema, R. A. Houghton, J. I. House, A. K. Jain, T. Johannessen, E. Kato, R. F. Keeling, V. Kitidis, K. Klein Goldewijk, C. Koven, C. S. Landa, P. Landschützer, A. Lenton, I. D. Lima, G. Marland, J. T. Mathis, N. Metzl, Y. Nojiri, A. Olsen, T. Ono, S. Peng, W. Peters, B. Pfeil, B. Poulter, M. R. Raupach, P. Regnier, C. Rödenbeck, S. Saito, J. E. Salisbury, U. Schuster, J. Schwinger, R. Séférian, J. Segschneider, T. Steinhoff, B. D. Stocker, A. J. Sutton, T. Takahashi, B. Tilbrook, G. R. van der Werf, N. Viovy, Y.-P. Wang, R. Wanninkhof, A. Wiltshire, and N. Zeng
Earth Syst. Sci. Data, 7, 47–85, https://doi.org/10.5194/essd-7-47-2015, https://doi.org/10.5194/essd-7-47-2015, 2015
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Carbon dioxide (CO2) emissions from human activities (burning fossil fuels and cement production, deforestation and other land-use change) are set to rise again in 2014.
This study (updated yearly) makes an accurate assessment of anthropogenic CO2 emissions and their redistribution between the atmosphere, ocean, and terrestrial biosphere in order to better understand the global carbon cycle, support the development of climate policies, and project future climate change.
C. D. Nevison, M. Manizza, R. F. Keeling, M. Kahru, L. Bopp, J. Dunne, J. Tiputra, T. Ilyina, and B. G. Mitchell
Biogeosciences, 12, 193–208, https://doi.org/10.5194/bg-12-193-2015, https://doi.org/10.5194/bg-12-193-2015, 2015
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The observed seasonal cycles in atmospheric potential oxygen (APO) at five surface monitoring sites are compared to those inferred from the air-sea O2 fluxes of six ocean biogeochemistry models. The simulated air-sea fluxes are translated into APO seasonal cycles using a matrix method that takes into account atmospheric transport model (ATM) uncertainty among 13 different ATMs. Net primary production (NPP), estimated from satellite ocean color data, is also compared to model output.
C. Rödenbeck, D. C. E. Bakker, N. Metzl, A. Olsen, C. Sabine, N. Cassar, F. Reum, R. F. Keeling, and M. Heimann
Biogeosciences, 11, 4599–4613, https://doi.org/10.5194/bg-11-4599-2014, https://doi.org/10.5194/bg-11-4599-2014, 2014
K. B. Rodgers, O. Aumont, S. E. Mikaloff Fletcher, Y. Plancherel, L. Bopp, C. de Boyer Montégut, D. Iudicone, R. F. Keeling, G. Madec, and R. Wanninkhof
Biogeosciences, 11, 4077–4098, https://doi.org/10.5194/bg-11-4077-2014, https://doi.org/10.5194/bg-11-4077-2014, 2014
C. Le Quéré, G. P. Peters, R. J. Andres, R. M. Andrew, T. A. Boden, P. Ciais, P. Friedlingstein, R. A. Houghton, G. Marland, R. Moriarty, S. Sitch, P. Tans, A. Arneth, A. Arvanitis, D. C. E. Bakker, L. Bopp, J. G. Canadell, L. P. Chini, S. C. Doney, A. Harper, I. Harris, J. I. House, A. K. Jain, S. D. Jones, E. Kato, R. F. Keeling, K. Klein Goldewijk, A. Körtzinger, C. Koven, N. Lefèvre, F. Maignan, A. Omar, T. Ono, G.-H. Park, B. Pfeil, B. Poulter, M. R. Raupach, P. Regnier, C. Rödenbeck, S. Saito, J. Schwinger, J. Segschneider, B. D. Stocker, T. Takahashi, B. Tilbrook, S. van Heuven, N. Viovy, R. Wanninkhof, A. Wiltshire, and S. Zaehle
Earth Syst. Sci. Data, 6, 235–263, https://doi.org/10.5194/essd-6-235-2014, https://doi.org/10.5194/essd-6-235-2014, 2014
L. R. Welp, R. F. Keeling, R. F. Weiss, W. Paplawsky, and S. Heckman
Atmos. Meas. Tech., 6, 1217–1226, https://doi.org/10.5194/amt-6-1217-2013, https://doi.org/10.5194/amt-6-1217-2013, 2013
C. Le Quéré, R. J. Andres, T. Boden, T. Conway, R. A. Houghton, J. I. House, G. Marland, G. P. Peters, G. R. van der Werf, A. Ahlström, R. M. Andrew, L. Bopp, J. G. Canadell, P. Ciais, S. C. Doney, C. Enright, P. Friedlingstein, C. Huntingford, A. K. Jain, C. Jourdain, E. Kato, R. F. Keeling, K. Klein Goldewijk, S. Levis, P. Levy, M. Lomas, B. Poulter, M. R. Raupach, J. Schwinger, S. Sitch, B. D. Stocker, N. Viovy, S. Zaehle, and N. Zeng
Earth Syst. Sci. Data, 5, 165–185, https://doi.org/10.5194/essd-5-165-2013, https://doi.org/10.5194/essd-5-165-2013, 2013
C. Rödenbeck, R. F. Keeling, D. C. E. Bakker, N. Metzl, A. Olsen, C. Sabine, and M. Heimann
Ocean Sci., 9, 193–216, https://doi.org/10.5194/os-9-193-2013, https://doi.org/10.5194/os-9-193-2013, 2013
C. E. Yver, H. D. Graven, D. D. Lucas, P. J. Cameron-Smith, R. F. Keeling, and R. F. Weiss
Atmos. Chem. Phys., 13, 1837–1852, https://doi.org/10.5194/acp-13-1837-2013, https://doi.org/10.5194/acp-13-1837-2013, 2013
Related subject area
Subject: Gases | Technique: In Situ Measurement | Topic: Instruments and Platforms
Simple water vapor sampling for stable isotope analysis using affordable valves and bags
On path length, beam divergence, and retroreflector array size in open-path FTIR spectroscopy
A modular approach to volatile organic compound samplers for tethered balloon and drone platforms
Performance validation and calibration conditions for novel dynamic baseline tracking air sensors in long-term field monitoring
Observation of greenhouse gas vertical profiles in the boundary layer of the Mount Qomolangma region using a multirotor UAV
Description and Validation of a Carbon Monoxide and Nitrous Oxide Instrument for High-Altitude Airborne Science (COMA)
Development of a portable laser-flash photolysis Faraday rotation spectrometer for measuring atmospheric total OH reactivity
Surface distributions and vertical profiles of trace gases (CO, O3, NO, NO2) in the Arctic wintertime boundary layer using low-cost sensors during ALPACA-2022
Advances in an OH reactivity instrument for airborne field measurements
The ASK-16 motorized glider: an airborne eddy covariance platform to measure turbulence, energy, and matter fluxes
Development of a Peltier-based chilled-mirror hygrometer, SKYDEW, for tropospheric and lower-stratospheric water vapor measurements
Vertical distribution of halogenated trace gases in the summer Arctic stratosphere determined by two independent in situ methods
Deployment and evaluation of an NH4+∕ H3O+ reagent ion switching chemical ionization mass spectrometer for the detection of reduced and oxygenated gas-phase organic compounds
An economical tunable diode laser spectrometer for fast-response measurements of water vapor in the atmospheric boundary layer
Eddy covariance with slow-response greenhouse gas analysers on tall towers: bridging atmospheric and ecosystem greenhouse gas networks
An overview of outdoor low-cost gas-phase air quality sensor deployments: current efforts, trends, and limitations
Multiphysical description of atmospheric pressure interface chemical ionisation in MION2 and Eisele type inlets
Improving raw readings from ozone low cost sensors using artificial intelligence for air quality monitoring
Development of a Forced Advection Sampling Technique (FAST) for Quantification of Methane Emissions from Orphaned Wells
A portable nitrogen dioxide instrument using cavity-enhanced absorption spectroscopy
Development and deployment of a mid-cost CO2 sensor monitoring network to support atmospheric inverse modeling for quantifying urban CO2 emissions in Paris
UAV-based in situ measurements of CO2 and CH4 fluxes over complex natural ecosystems
A new aerial approach for quantifying and attributing methane emissions: implementation and validation
Drone CO2 measurements during the Tajogaite volcanic eruption
Multi-decadal atmospheric carbon dioxide measurements in Hungary, central Europe
Reliable water vapour isotopic composition measurements at low humidity using frequency-stabilised cavity ring-down spectroscopy
A measurement system for CO2 and CH4 emissions quantification of industrial sites using a new in situ concentration sensor operated on board uncrewed aircraft vehicles
Using metal oxide gas sensors to estimate the emission rates and locations of methane leaks in an industrial site: assessment with controlled methane releases
Toward on-demand measurements of greenhouse gas emissions using an uncrewed aircraft AirCore system
Long-term evaluation of commercial air quality sensors: an overview from the QUANT (Quantification of Utility of Atmospheric Network Technologies) study
In-flight characterization of a compact airborne quantum cascade laser absorption spectrometer
Full characterization and calibration of a transfer standard monitor for atmospheric radon measurements
Observing low-altitude features in ozone concentrations in a shoreline environment via uncrewed aerial systems
An integrated uncrewed aerial vehicle platform with sensing and sampling systems for the measurement of air pollutant concentrations
Design and evaluation of a low-cost sensor node for near-background methane measurement
Development of a Multichannel Organics In situ enviRonmental Analyzer (MOIRA) for mobile measurements of volatile organic compounds
Evaluation of Aeris mid-infrared absorption (MIRA), Picarro CRDS (cavity ring-down spectroscopy) G2307, and dinitrophenylhydrazine (DNPH)-based sampling for long-term formaldehyde monitoring efforts
Performance characterization of a laminar gas inlet
Validation and field application of a low-cost device to measure CO2 and evapotranspiration (ET) fluxes
Identifying and correcting interferences to PTR-ToF-MS measurements of isoprene and other urban volatile organic compounds
Development of a continuous UAV-mounted air sampler and application to the quantification of CO2 and CH4 emissions from a major coking plant
Uptake behavior of polycyclic aromatic compounds during field calibrations of the XAD-based passive air sampler across seasons and locations
Effect of land–sea air mass transport on spatiotemporal distributions of atmospheric CO2 and CH4 mixing ratios over the southern Yellow Sea
HYPHOP: a tool for high-altitude, long-range monitoring of hydrogen peroxide and higher organic peroxides in the atmosphere
Portable, low-cost samplers for distributed sampling of atmospheric gases
SI-traceable validation of a laser spectrometer for balloon-borne measurements of water vapor in the upper atmosphere
Field evaluation of low-cost electrochemical air quality gas sensors under extreme temperature and relative humidity conditions
A novel, cost-effective analytical method for measuring high-resolution vertical profiles of stratospheric trace gases using a gas chromatograph coupled with an electron capture detector
Ethylene oxide monitor with part-per-trillion precision for in situ measurements
Development of an automated pump-efficiency measuring system for ozonesondes utilizing an airbag-type flowmeter
Adrian Dahlmann, John D. Marshall, David Dubbert, Mathias Hoffmann, and Maren Dubbert
Atmos. Meas. Tech., 18, 2607–2618, https://doi.org/10.5194/amt-18-2607-2025, https://doi.org/10.5194/amt-18-2607-2025, 2025
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Water-stable isotopes are commonly used in hydrological and ecological research. Until now, measurements have been obtained either destructively or directly in the field. Here, we present a novel, affordable, and easy-to-use approach to measure the stable isotope signatures of soil water. Our gas bag approach demonstrates a high accuracy and extends usability by allowing water vapor samples to be collected and stored in the field without the need for an instrument or a permanent power supply.
Cameron E. N. Power and Aldona Wiacek
Atmos. Meas. Tech., 18, 2537–2552, https://doi.org/10.5194/amt-18-2537-2025, https://doi.org/10.5194/amt-18-2537-2025, 2025
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The choice of path length and retroreflector array size in open-path Fourier transform infrared spectroscopy must be made with care. Longer paths increase target gas absorption (lowering detection limits), and larger retroreflector arrays increase the return signal (improving retrieved concentration precision), but there are limitations to both. An optimum array size and path combination exists in each specific observational environment and application, as explored in this work.
Meghan Guagenti, Darielle Dexheimer, Alexandra Ulinksi, Paul Walter, James H. Flynn III, and Sascha Usenko
Atmos. Meas. Tech., 18, 2125–2136, https://doi.org/10.5194/amt-18-2125-2025, https://doi.org/10.5194/amt-18-2125-2025, 2025
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A robust, automatic volatile organic compound (VOC) collection system was developed for vertical VOC sampling associated with the 2022 DOE ARM-program-led TRACER in Houston, Texas. This modular sampler has been developed to measure vertical profiles of VOCs to improve near-surface characterization. This article helps fill the current lack of commercially available options for aerial VOC sampling and serves to support and encourage researchers to build and develop custom samplers.
Han Mei, Peng Wei, Meisam Ahmadi Ghadikolaei, Nirmal Kumar Gali, Ya Wang, and Zhi Ning
Atmos. Meas. Tech., 18, 1771–1785, https://doi.org/10.5194/amt-18-1771-2025, https://doi.org/10.5194/amt-18-1771-2025, 2025
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Long-term field testing across diverse climatic environments is conducted to identify the optimized calibration conditions for NO2, NO, CO and O3 electrochemical sensors. The results uncovered three factors that influence calibration performance: calibration period, concentration range and time averaging. We developed a comprehensive framework for the best sensor calibration practices, which serves as a valuable reference for calibrating various sensor types used in air quality monitoring.
Ying Zhou, Congcong Qiao, Minqiang Zhou, Yilong Wang, Xiangjun Tian, Yinghong Wang, and Minzheng Duan
Atmos. Meas. Tech., 18, 1609–1619, https://doi.org/10.5194/amt-18-1609-2025, https://doi.org/10.5194/amt-18-1609-2025, 2025
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We developed an automated, flexible atmospheric sampling device for various platforms. During a 5 d field campaign in the Mount Qomolangma region, we performed 15 flights using the device mounted on a hexacopter unoccupied aerial vehicle (UAV). A total of 139 samples were analyzed using an Agilent 7890A gas chromatograph. Vertical profiles of four greenhouse gases (carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O), and sulfur hexafluoride (SF6)) were analyzed and discussed.
Emma L. Yates, Levi M. Golston, James R. Podolske, Laura T. Iraci, Kristen E. Okorn, Caroline Dang, Roy R. Johnson, James Eilers, Richard Kolyer, Ian Astley, and J. Brian Leen
EGUsphere, https://doi.org/10.5194/egusphere-2025-1081, https://doi.org/10.5194/egusphere-2025-1081, 2025
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In this work, we describe the development of the Carbon monOxide Measurement from Ames (COMA) instrument for measurement of carbon monoxide (CO) and nitrous oxide (N2O) aboard NASA's WB-57 high altitude research aircraft. We detail the modifications and testing conducted as well as details of COMA's performance during research flights for NASA’s Asian summer monsoon Chemical & CLImate Project (ACCLIP) 2022 campaign.
Bo Fang, Nana Wei, Weixiong Zhao, Nana Yang, Hao Zhou, Heng Zhang, Jiarong Li, Weijun Zhang, Yanyu Lu, Zhu Zhu, and Yue Liu
Atmos. Meas. Tech., 18, 1243–1256, https://doi.org/10.5194/amt-18-1243-2025, https://doi.org/10.5194/amt-18-1243-2025, 2025
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A portable laser-flash photolysis Faraday rotation spectrometer for measuring atmospheric total hydroxyl (OH) reactivity was developed, with optical box dimensions of 130 cm × 40 cm × 35 cm. It features a pump–probe multi-pass cell with a high overlapping factor of 75.4 %. The instrument’s precision and uncertainty are 1.0 s-1 (1σ, 300 s) and within 2 s-1, respectively. This portable, cost-effective instrument expands current measurement capabilities and is convenient for field applications.
Brice Barret, Patrice Medina, Natalie Brett, Roman Pohorsky, Kathy S. Law, Slimane Bekki, Gilberto J. Fochesatto, Julia Schmale, Steve R. Arnold, Andrea Baccarini, Maurizio Busetto, Meeta Cesler-Maloney, Barbara D'Anna, Stefano Decesari, Jingqiu Mao, Gianluca Pappaccogli, Joel Savarino, Federico Scoto, and William R. Simpson
Atmos. Meas. Tech., 18, 1163–1184, https://doi.org/10.5194/amt-18-1163-2025, https://doi.org/10.5194/amt-18-1163-2025, 2025
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The Fairbanks area experiences severe pollution episodes in winter because of enhanced emissions of pollutants trapped near the surface by strong temperature inversions. Low-cost sensors were deployed on board a car and a tethered balloon to measure the concentrations of gaseous pollutants (CO, O3, and NOx) in Fairbanks during winter 2022. Data calibration with reference measurements and machine learning methods enabled us to document pollution at the surface and power plant plumes aloft.
Hendrik Fuchs, Aaron Stainsby, Florian Berg, René Dubus, Michelle Färber, Andreas Hofzumahaus, Frank Holland, Kelvin H. Bates, Steven S. Brown, Matthew M. Coggon, Glenn S. Diskin, Georgios I. Gkatzelis, Christopher M. Jernigan, Jeff Peischl, Michael A. Robinson, Andrew W. Rollins, Nell B. Schafer, Rebecca H. Schwantes, Chelsea E. Stockwell, Patrick R. Veres, Carsten Warneke, Eleanor M. Waxman, Lu Xu, Kristen Zuraski, Andreas Wahner, and Anna Novelli
Atmos. Meas. Tech., 18, 881–895, https://doi.org/10.5194/amt-18-881-2025, https://doi.org/10.5194/amt-18-881-2025, 2025
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Significant improvements have been made to the instruments used to measure OH reactivity, which is equivalent to the sum of air pollutant concentrations. Accurate and precise measurements with a high time resolution have been achieved, allowing use on aircraft, as demonstrated during flights in the USA.
Inge Wiekenkamp, Anna Katharina Lehmann, Alexander Bütow, Jörg Hartmann, Stefan Metzger, Thomas Ruhtz, Christian Wille, Mathias Zöllner, and Torsten Sachs
Atmos. Meas. Tech., 18, 749–772, https://doi.org/10.5194/amt-18-749-2025, https://doi.org/10.5194/amt-18-749-2025, 2025
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Airborne eddy covariance platforms are crucial to measure three-dimensional wind and turbulent matter and energy transport between the surface and the atmosphere at larger scales. In this study, we introduce a new airborne eddy covariance platform (Schleicher ASK-16) and demonstrate that this platform is able to accurately measure turbulent fluxes and wind vectors. Data from this platform can help to build bridges between local tower measurements and remote-sensing-based products.
Takuji Sugidachi, Masatomo Fujiwara, Kensaku Shimizu, Shin-Ya Ogino, Junko Suzuki, and Ruud J. Dirksen
Atmos. Meas. Tech., 18, 509–531, https://doi.org/10.5194/amt-18-509-2025, https://doi.org/10.5194/amt-18-509-2025, 2025
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A Peltier-based chilled-mirror hygrometer, SKYDEW, has been developed to measure tropospheric and stratospheric water vapor. Continuous accurate measurements of water vapor are essential for climate monitoring. More than 40 soundings with SKYDEW have been conducted since 2011 to evaluate the performance. The result of soundings at tropical and midlatitudes demonstrated that SKYDEW is able to measure up to an altitude of 20–25 km for daytime soundings and above 25 km for nighttime soundings.
Johannes C. Laube, Tanja J. Schuck, Huilin Chen, Markus Geldenhuys, Steven van Heuven, Timo Keber, Maria Elena Popa, Elinor Tuffnell, Bärbel Vogel, Thomas Wagenhäuser, Alessandro Zanchetta, and Andreas Engel
EGUsphere, https://doi.org/10.5194/egusphere-2024-4034, https://doi.org/10.5194/egusphere-2024-4034, 2025
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A large balloon was launched in summer 2021 in the Arctic to carry instruments for trace gas measurements up to 32 km, above the reach of aircraft. The main aims were to evaluate different techniques and atmospheric processes. We focus on halogenated greenhouse gases and ozone-depleting substances. For this, air was collected with the AirCore technique and a cryogenic air sampler and measured after the flight. A companion paper reports observations of major greenhouse gases.
Cort L. Zang and Megan D. Willis
Atmos. Meas. Tech., 18, 17–35, https://doi.org/10.5194/amt-18-17-2025, https://doi.org/10.5194/amt-18-17-2025, 2025
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Atmospheric chemistry of the diverse pool of reactive organic carbon (ROC; all organic species excluding methane) controls air quality, both indoors and outdoors, and influences Earth's climate. However, many important ROC compounds in the atmosphere are difficult to measure. We demonstrate measurement of diverse ROC compounds in a single instrument at a forested site. This approach can improve our ability to measure a broad range of atmospheric ROC.
Emily D. Wein, Lars E. Kalnajs, and Darin W. Toohey
Atmos. Meas. Tech., 17, 7097–7107, https://doi.org/10.5194/amt-17-7097-2024, https://doi.org/10.5194/amt-17-7097-2024, 2024
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We describe a low-cost and small research-grade spectrometer for measurements of water vapor in the boundary layer. The instrument uses small Arduino microcontrollers and inexpensive laser diodes to reduce cost while maintaining high performance comparable to more expensive instruments. Performance was assessed with intercomparisons between commercially available instruments outdoors. The design's simplicity, performance, and price point allow it to be accessible to a variety of users.
Pedro Henrique Herig Coimbra, Benjamin Loubet, Olivier Laurent, Laura Bignotti, Mathis Lozano, and Michel Ramonet
Atmos. Meas. Tech., 17, 6625–6645, https://doi.org/10.5194/amt-17-6625-2024, https://doi.org/10.5194/amt-17-6625-2024, 2024
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This study presents direct flux measurements in tall towers using existing slow-response analysers and adding 3D sonic anemometers. This way, we can significantly improve greenhouse gas monitoring with little extra instrumental effort. Slow-response analysers may be used here as the relevant frequency ranges depend on measuring height. Tall towers offer a large footprint, amplifying spatial coverage. The presented concept is a valuable bridge between atmospheric and ecosystem communities.
Kristen Okorn and Laura T. Iraci
Atmos. Meas. Tech., 17, 6425–6457, https://doi.org/10.5194/amt-17-6425-2024, https://doi.org/10.5194/amt-17-6425-2024, 2024
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We reviewed 60 sensor networks and 17 related efforts (sensor review papers and data accessibility projects) to better understand the landscape of stationary low-cost gas-phase sensor networks deployed in outdoor environments worldwide. Gaps in monitoring efforts include the availability of gas-phase measurements compared to particulate matter (PM) and geographic coverage gaps (the Global South, rural areas). We conclude with a summary of cross-network unification and quality control efforts.
Henning Finkenzeller, Jyri Mikkilä, Cecilia Righi, Paxton Juuti, Mikko Sipilä, Matti Rissanen, Douglas Worsnop, Aleksei Shcherbinin, Nina Sarnela, and Juha Kangasluoma
Atmos. Meas. Tech., 17, 5989–6001, https://doi.org/10.5194/amt-17-5989-2024, https://doi.org/10.5194/amt-17-5989-2024, 2024
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Chemical ionisation mass spectrometry is used in the atmospheric sciences to measure trace gas concentrations. Neutral gases require charging in inlets before the mass-to-charge ratio of the resulting ions can be analysed. This study uses multiphysics modelling to investigate how the MION2 and Eisele type inlets work and shows the effect of tuning parameters and their current limitations. The findings are helpful for inlet users and are expected to aid in developing improved inlets.
Guillem Montalban-Faet, Eric Meneses-Albala, Santiago Felici-Castell, Juan J. Perez-Solano, and Jaume Segura-Garcia
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2024-127, https://doi.org/10.5194/amt-2024-127, 2024
Revised manuscript accepted for AMT
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WHO warns of ground-level ozone problems in urban areas, recommending increased monitoring for which low-cost sensors coupled with artificial intelligence are an excellent alternative.
Mohit L. Dubey, Andre Santos, Andrew B. Moyes, Ken Reichl, James E. Lee, Manvendra K. Dubey, Corentin LeYhuelic, Evan Variano, Emily Follansbee, Fotini K. Chow, and Sébastien C. Biraud
EGUsphere, https://doi.org/10.5194/egusphere-2024-3040, https://doi.org/10.5194/egusphere-2024-3040, 2024
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Orphaned wells, meaning wells lacking responsible owners, pose a significant and poorly understood environmental challenge. We propose, develop, and test a novel method for estimating emissions from orphaned wells using a Forced Advection Sampling Technique (FAST) that can overcome many of the limitations in current methods (cost, accuracy, safety). Our results suggest that the FAST method can provide a low-cost alternative to existing methods over a range of leak rates.
Steven A. Bailey, Reem A. Hannun, Andrew K. Swanson, and Thomas F. Hanisco
Atmos. Meas. Tech., 17, 5903–5910, https://doi.org/10.5194/amt-17-5903-2024, https://doi.org/10.5194/amt-17-5903-2024, 2024
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We have developed a portable, optically based instrument that measures NO2. It consumes less than 6 W of power, so it can easily run off a small battery. This instrument has made both balloon and UAV flights. NO2 measurement results compare favorably with other known NO2 instruments. We find this instrument to be stable with repeatable results compared with calibration sources. Material cost to build a single instrument is around USD 4000. This could be lowered with economies of scale.
Jinghui Lian, Olivier Laurent, Mali Chariot, Luc Lienhardt, Michel Ramonet, Hervé Utard, Thomas Lauvaux, François-Marie Bréon, Grégoire Broquet, Karina Cucchi, Laurent Millair, and Philippe Ciais
Atmos. Meas. Tech., 17, 5821–5839, https://doi.org/10.5194/amt-17-5821-2024, https://doi.org/10.5194/amt-17-5821-2024, 2024
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We have designed and deployed a mid-cost medium-precision CO2 sensor monitoring network in Paris since July 2020. The data are automatically calibrated by a newly implemented data processing system. The accuracies of the mid-cost instruments vary from 1.0 to 2.4 ppm for hourly afternoon measurements. Our model–data analyses highlight prospects for integrating mid-cost instrument data with high-precision measurements to improve fine-scale CO2 emission quantification in urban areas.
Abdullah Bolek, Martin Heimann, and Mathias Göckede
Atmos. Meas. Tech., 17, 5619–5636, https://doi.org/10.5194/amt-17-5619-2024, https://doi.org/10.5194/amt-17-5619-2024, 2024
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This study describes the development of a new UAV platform to measure atmospheric greenhouse gas (GHG) mole fractions, 2D wind speed, air temperature, humidity, and pressure. Understanding GHG flux processes and controls across various ecosystems is essential for estimating the current and future state of climate change. It was shown that using the UAV platform for such measurements is beneficial for improving our understanding of GHG processes over complex landscapes.
Jonathan F. Dooley, Kenneth Minschwaner, Manvendra K. Dubey, Sahar H. El Abbadi, Evan D. Sherwin, Aaron G. Meyer, Emily Follansbee, and James E. Lee
Atmos. Meas. Tech., 17, 5091–5111, https://doi.org/10.5194/amt-17-5091-2024, https://doi.org/10.5194/amt-17-5091-2024, 2024
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Methane is a powerful greenhouse gas originating from both natural and human activities. We describe a new uncrewed aerial system (UAS) designed to measure methane emission rates over a wide range of scales. This system has been used for direct quantification of point sources and distributed emitters over scales of up to 1 km. The system uses simultaneous measurements of methane and ethane to distinguish between different kinds of natural and human-related emission sources.
John Ericksen, Tobias P. Fischer, G. Matthew Fricke, Scott Nowicki, Nemesio M. Pérez, Pedro Hernández Pérez, Eleazar Padrón González, and Melanie E. Moses
Atmos. Meas. Tech., 17, 4725–4736, https://doi.org/10.5194/amt-17-4725-2024, https://doi.org/10.5194/amt-17-4725-2024, 2024
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Volcanic eruptions emit significant quantities of carbon dioxide (CO2) to the atmosphere. We present a new method for directly determining the CO2 emission from a volcanic eruption on the island of La Palma, Spain, using an unpiloted aerial vehicle (UAV). We also collected samples of the emitted CO2 and analyzed their isotopic composition. Together with the emission rate the isotopic data provide valuable information on the state of volcanic activity and the potential evolution of the eruption.
László Haszpra
Atmos. Meas. Tech., 17, 4629–4647, https://doi.org/10.5194/amt-17-4629-2024, https://doi.org/10.5194/amt-17-4629-2024, 2024
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The paper evaluates a 30-year-long atmospheric CO2 data series from a mid-continental central European site, Hegyhátsál (HUN). It presents the site-specific features observed in the long-term evolution of the atmospheric CO2 concentration. Since the measurement data are widely used in atmospheric inverse models and budget calculations all around the world, the paper provides potentially valuable information for model tuning and interpretation of the model results.
Mathieu Casado, Amaelle Landais, Tim Stoltmann, Justin Chaillot, Mathieu Daëron, Fréderic Prié, Baptiste Bordet, and Samir Kassi
Atmos. Meas. Tech., 17, 4599–4612, https://doi.org/10.5194/amt-17-4599-2024, https://doi.org/10.5194/amt-17-4599-2024, 2024
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Measuring water isotopic composition in Antarctica is difficult because of the extremely cold temperature in winter. Here, we designed a new infrared spectrometer able to measure the vapour isotopic composition during more than 95 % of the year in the coldest locations of Antarctica, whereas current commercial instruments are only able to measure during the warm summer months in the interior.
Jean-Louis Bonne, Ludovic Donnat, Grégory Albora, Jérémie Burgalat, Nicolas Chauvin, Delphine Combaz, Julien Cousin, Thomas Decarpenterie, Olivier Duclaux, Nicolas Dumelié, Nicolas Galas, Catherine Juery, Florian Parent, Florent Pineau, Abel Maunoury, Olivier Ventre, Marie-France Bénassy, and Lilian Joly
Atmos. Meas. Tech., 17, 4471–4491, https://doi.org/10.5194/amt-17-4471-2024, https://doi.org/10.5194/amt-17-4471-2024, 2024
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We present a top-down approach to quantify CO2 and CH4 emissions at the scale of an industrial site, based on a mass balance model relying on atmospheric concentrations measurements from a new sensor embarked on board uncrewed aircraft vehicles (UAVs). We present a laboratory characterization of our sensor and a field validation of our quantification method, together with field application to the monitoring of two real-world offshore oil and gas platforms.
Rodrigo Rivera-Martinez, Pramod Kumar, Olivier Laurent, Gregoire Broquet, Christopher Caldow, Ford Cropley, Diego Santaren, Adil Shah, Cécile Mallet, Michel Ramonet, Leonard Rivier, Catherine Juery, Olivier Duclaux, Caroline Bouchet, Elisa Allegrini, Hervé Utard, and Philippe Ciais
Atmos. Meas. Tech., 17, 4257–4290, https://doi.org/10.5194/amt-17-4257-2024, https://doi.org/10.5194/amt-17-4257-2024, 2024
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We explore the use of metal oxide semiconductors (MOSs) as a low-cost alternative for detecting and measuring CH4 emissions from industrial facilities. MOSs were exposed to several controlled releases to test their accuracy in detecting and quantifying emissions. Two reconstruction models were compared, and emission estimates were computed using a Gaussian dispersion model. Findings show that MOSs can provide accurate emission estimates with a 25 % emission rate error and a 9.5 m location error.
Zihan Zhu, Javier González-Rocha, Yifan Ding, Isis Frausto-Vicencio, Sajjan Heerah, Akula Venkatram, Manvendra Dubey, Don Collins, and Francesca M. Hopkins
Atmos. Meas. Tech., 17, 3883–3895, https://doi.org/10.5194/amt-17-3883-2024, https://doi.org/10.5194/amt-17-3883-2024, 2024
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Increases in agriculture, oil and gas, and waste management activities have contributed to the increase in atmospheric methane levels and resultant climate warming. In this paper, we explore the use of small uncrewed aircraft systems (sUASs) and AirCore technology to detect and quantify methane emissions. Results from field experiments demonstrate that sUASs and AirCore technology can be effective for detecting and quantifying methane emissions in near real time.
Sebastian Diez, Stuart Lacy, Hugh Coe, Josefina Urquiza, Max Priestman, Michael Flynn, Nicholas Marsden, Nicholas A. Martin, Stefan Gillott, Thomas Bannan, and Pete M. Edwards
Atmos. Meas. Tech., 17, 3809–3827, https://doi.org/10.5194/amt-17-3809-2024, https://doi.org/10.5194/amt-17-3809-2024, 2024
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In this paper we present an overview of the QUANT project, which to our knowledge is one of the largest evaluations of commercial sensors to date. The objective was to evaluate the performance of a range of commercial products and also to nourish the different applications in which these technologies can offer relevant information.
Linda Ort, Lenard Lukas Röder, Uwe Parchatka, Rainer Königstedt, Daniel Crowley, Frank Kunz, Ralf Wittkowski, Jos Lelieveld, and Horst Fischer
Atmos. Meas. Tech., 17, 3553–3565, https://doi.org/10.5194/amt-17-3553-2024, https://doi.org/10.5194/amt-17-3553-2024, 2024
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Airborne in situ measurements are of great importance to collect valuable data to improve our knowledge of the atmosphere but also present challenges which demand specific designs. This study presents an IR spectrometer for airborne trace-gas measurements with high data efficiency and a simple, compact design. Its in-flight performance is characterized with the help of a test flight and a comparison with another spectrometer. Moreover, results from its first campaign highlight its benefits.
Roger Curcoll, Claudia Grossi, Stefan Röttger, and Arturo Vargas
Atmos. Meas. Tech., 17, 3047–3065, https://doi.org/10.5194/amt-17-3047-2024, https://doi.org/10.5194/amt-17-3047-2024, 2024
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This paper presents a new user-friendly version of the Atmospheric Radon MONitor (ARMON). The efficiency of the instrument is of 0.0057 s-1, obtained using different techniques at Spanish and German chambers. The total calculated uncertainty of the ARMON for hourly radon concentrations above 5 Bq m-3 is lower than 10 % (k = 1). Results confirm that the ARMON is suitable to measure low-level radon activity concentrations and to be used as a transfer standard to calibrate in situ radon monitors.
Josie K. Radtke, Benjamin N. Kies, Whitney A. Mottishaw, Sydney M. Zeuli, Aidan T. H. Voon, Kelly L. Koerber, Grant W. Petty, Michael P. Vermeuel, Timothy H. Bertram, Ankur R. Desai, Joseph P. Hupy, R. Bradley Pierce, Timothy J. Wagner, and Patricia A. Cleary
Atmos. Meas. Tech., 17, 2833–2847, https://doi.org/10.5194/amt-17-2833-2024, https://doi.org/10.5194/amt-17-2833-2024, 2024
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The use of uncrewed aircraft systems (UASs) to conduct a vertical profiling of ozone and meteorological variables was evaluated using comparisons between tower or ground observations and UAS-based measurements. Changes to the UAS profiler showed an improvement in performance. The profiler was used to see the impact of Chicago pollution plumes on a shoreline area near Lake Michigan.
Chen-Wei Liang and Chang-Hung Shen
Atmos. Meas. Tech., 17, 2671–2686, https://doi.org/10.5194/amt-17-2671-2024, https://doi.org/10.5194/amt-17-2671-2024, 2024
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In the present study, a UAV platform with sensing and sampling systems was developed for 3D air pollutant concentration measurements. The sensing system of this platform contains multiple microsensors and IoT technologies for obtaining the real-time 3D distributions of critical air pollutants. The sampling system contains gas sampling sets and a 1 L Tedlar bag instead of a canister for the 3D measurement of VOC concentrations in accordance with the TO-15 method of the US EPA.
Daniel Furuta, Bruce Wilson, Albert A. Presto, and Jiayu Li
Atmos. Meas. Tech., 17, 2103–2121, https://doi.org/10.5194/amt-17-2103-2024, https://doi.org/10.5194/amt-17-2103-2024, 2024
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Methane is an important driver of climate change and is challenging to inexpensively sense in low atmospheric concentrations. We developed a low-cost sensor to monitor methane and tested it in indoor and outdoor settings. Our device shows promise for monitoring low levels of methane. We characterize its limitations and suggest future research directions for further development.
Audrey J. Dang, Nathan M. Kreisberg, Tyler L. Cargill, Jhao-Hong Chen, Sydney Hornitschek, Remy Hutheesing, Jay R. Turner, and Brent J. Williams
Atmos. Meas. Tech., 17, 2067–2087, https://doi.org/10.5194/amt-17-2067-2024, https://doi.org/10.5194/amt-17-2067-2024, 2024
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The Multichannel Organics In situ enviRonmental Analyzer (MOIRA) is a new instrument for measuring speciated volatile organic compounds (VOCs) in the air and has been developed for mapping concentrations from a hybrid car. MOIRA is characterized in the lab and pilot field studies of indoor air in a single-family residence and outdoor air during a mobile deployment. Future applications include indoor, outdoor, and lab measurements to grasp the impact of VOCs on air quality, health, and climate.
Asher P. Mouat, Zelda A. Siegel, and Jennifer Kaiser
Atmos. Meas. Tech., 17, 1979–1994, https://doi.org/10.5194/amt-17-1979-2024, https://doi.org/10.5194/amt-17-1979-2024, 2024
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Three fast-measurement formaldehyde monitors were deployed at two field sites in Atlanta, GA, over 1 year. Four different zeroing methods were tested to develop an optimal field setup as well as procedures for instrument calibration. Observations agreed well after calibration but were much higher compared to the TO-11A monitoring method, which is the golden standard. Historical HCHO concentrations were compared with measurements in this work, showing a 22 % reduction in midday HCHO since 1999.
Da Yang, Margarita Reza, Roy Mauldin, Rainer Volkamer, and Suresh Dhaniyala
Atmos. Meas. Tech., 17, 1463–1474, https://doi.org/10.5194/amt-17-1463-2024, https://doi.org/10.5194/amt-17-1463-2024, 2024
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This paper evaluates the performance of an aircraft gas inlet. Here, we use computational fluid dynamics (CFD) and experiments to demonstrate the role of turbulence in determining sampling performance of a gas inlet and identify ideal conditions for inlet operation to minimize gas loss. Experiments conducted in a high-speed wind tunnel under near-aircraft speeds validated numerical results. We believe that the results obtained from this work will greatly inform future gas inlet studies.
Reena Macagga, Michael Asante, Geoffroy Sossa, Danica Antonijević, Maren Dubbert, and Mathias Hoffmann
Atmos. Meas. Tech., 17, 1317–1332, https://doi.org/10.5194/amt-17-1317-2024, https://doi.org/10.5194/amt-17-1317-2024, 2024
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Using only low-cost microcontrollers and sensors, we constructed a measurement device to accurately and precisely obtain atmospheric carbon dioxide and water fluxes. The device was tested against known concentration increases and high-cost, commercial sensors during a laboratory and field experiment. We additionally tested the device over a longer period in a field study in Ghana during which the net ecosystem carbon balance and water use efficiency of maize cultivation were studied.
Matthew M. Coggon, Chelsea E. Stockwell, Megan S. Claflin, Eva Y. Pfannerstill, Lu Xu, Jessica B. Gilman, Julia Marcantonio, Cong Cao, Kelvin Bates, Georgios I. Gkatzelis, Aaron Lamplugh, Erin F. Katz, Caleb Arata, Eric C. Apel, Rebecca S. Hornbrook, Felix Piel, Francesca Majluf, Donald R. Blake, Armin Wisthaler, Manjula Canagaratna, Brian M. Lerner, Allen H. Goldstein, John E. Mak, and Carsten Warneke
Atmos. Meas. Tech., 17, 801–825, https://doi.org/10.5194/amt-17-801-2024, https://doi.org/10.5194/amt-17-801-2024, 2024
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Mass spectrometry is a tool commonly used to measure air pollutants. This study evaluates measurement artifacts produced in the proton-transfer-reaction mass spectrometer. We provide methods to correct these biases and better measure compounds that degrade air quality.
Tianran Han, Conghui Xie, Yayong Liu, Yanrong Yang, Yuheng Zhang, Yufei Huang, Xiangyu Gao, Xiaohua Zhang, Fangmin Bao, and Shao-Meng Li
Atmos. Meas. Tech., 17, 677–691, https://doi.org/10.5194/amt-17-677-2024, https://doi.org/10.5194/amt-17-677-2024, 2024
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This study reported an integrated UAV measurement platform for GHG monitoring and its application for emission quantification from a coking plant. The key element of this system is a newly designed air sampler, consisting of a 150 m long tube with remote-controlled time stamping. When comparing the top-down results to those derived from the bottom-up inventory method, the present findings indicate that the use of IPCC emission factors for emission calculations can lead to overestimation.
Yuening Li, Faqiang Zhan, Yushan Su, Ying Duan Lei, Chubashini Shunthirasingham, Zilin Zhou, Jonathan P. D. Abbatt, Hayley Hung, and Frank Wania
Atmos. Meas. Tech., 17, 715–729, https://doi.org/10.5194/amt-17-715-2024, https://doi.org/10.5194/amt-17-715-2024, 2024
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A simple device for sampling gases from the atmosphere without the help of pumps was calibrated for an important group of hazardous air pollutants called polycyclic aromatic compounds (PACs). While the sampler appeared to perform well when used for relatively short periods of up to several months, some PACs were lost from the sampler during longer deployments. Sampling rates that can be used to quantitatively interpret the quantities of PACs taken up in the device have been derived.
Jiaxin Li, Kunpeng Zang, Yi Lin, Yuanyuan Chen, Shuo Liu, Shanshan Qiu, Kai Jiang, Xuemei Qing, Haoyu Xiong, Haixiang Hong, Shuangxi Fang, Honghui Xu, and Yujun Jiang
Atmos. Meas. Tech., 16, 4757–4768, https://doi.org/10.5194/amt-16-4757-2023, https://doi.org/10.5194/amt-16-4757-2023, 2023
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Based on observed data of CO2 and CH4 and meteorological parameters over the Yellow Sea in November 2012 and June 2013, a data process and quality control method was optimized and established to filter the data influenced by multiple factors. Spatial and seasonal variations in CO2 and CH4 mixing ratios were mainly controlled by the East Asian Monsoon, while the influence of air–sea exchange was slight.
Zaneta Hamryszczak, Antonia Hartmann, Dirk Dienhart, Sascha Hafermann, Bettina Brendel, Rainer Königstedt, Uwe Parchatka, Jos Lelieveld, and Horst Fischer
Atmos. Meas. Tech., 16, 4741–4756, https://doi.org/10.5194/amt-16-4741-2023, https://doi.org/10.5194/amt-16-4741-2023, 2023
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Hydroperoxide measurements improve the understanding of atmospheric oxidation processes. We introduce an instrumental setup for airborne measurements. The aim of the work is the characterization of the measurement method with emphasis on interferences impacting instrumental uncertainty. Technical and physical challenges do not critically impact the instrumental performance. The instrument resolves dynamic processes, such as convective transport, as shown based on the CAFE-Brazil campaign.
James F. Hurley, Alejandra Caceres, Deborah F. McGlynn, Mary E. Tovillo, Suzanne Pinar, Roger Schürch, Ksenia Onufrieva, and Gabriel Isaacman-VanWertz
Atmos. Meas. Tech., 16, 4681–4692, https://doi.org/10.5194/amt-16-4681-2023, https://doi.org/10.5194/amt-16-4681-2023, 2023
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Volatile organic compounds (VOCs) have a wide range of sources and impacts on environments and human health that make them spatially, temporally, and chemically varied. Current methods lack the ability to collect samples in ways that provide spatial and chemical resolution without complex, costly instrumentation. We describe and validate a low-cost, portable VOC sampler and demonstrate its utility in collecting distributed coordinated samples.
Simone Brunamonti, Manuel Graf, Tobias Bühlmann, Céline Pascale, Ivan Ilak, Lukas Emmenegger, and Béla Tuzson
Atmos. Meas. Tech., 16, 4391–4407, https://doi.org/10.5194/amt-16-4391-2023, https://doi.org/10.5194/amt-16-4391-2023, 2023
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The abundance of water vapor (H2O) in the upper atmosphere has a significant impact on the rate of global warming. We developed a new lightweight spectrometer (ALBATROSS) for H2O measurements aboard meteorological balloons. Here, we assess the accuracy and precision of ALBATROSS using metrology-grade reference gases. The results demonstrate the exceptional potential of mid-infrared laser absorption spectroscopy as a new reference method for in situ measurements of H2O in the upper atmosphere.
Roubina Papaconstantinou, Marios Demosthenous, Spyros Bezantakos, Neoclis Hadjigeorgiou, Marinos Costi, Melina Stylianou, Elli Symeou, Chrysanthos Savvides, and George Biskos
Atmos. Meas. Tech., 16, 3313–3329, https://doi.org/10.5194/amt-16-3313-2023, https://doi.org/10.5194/amt-16-3313-2023, 2023
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In this paper, we investigate the performance of low-cost electrochemical gas sensors. We carried out yearlong measurements at a traffic air quality monitoring station, where the low-cost sensors were collocated with reference instruments and exposed to highly variable environmental conditions with extremely high temperatures and low relative humidity (RH). Sensors provide measurements that exhibit increasing errors and decreasing correlations as temperature increases and RH decreases.
Jianghanyang Li, Bianca C. Baier, Fred Moore, Tim Newberger, Sonja Wolter, Jack Higgs, Geoff Dutton, Eric Hintsa, Bradley Hall, and Colm Sweeney
Atmos. Meas. Tech., 16, 2851–2863, https://doi.org/10.5194/amt-16-2851-2023, https://doi.org/10.5194/amt-16-2851-2023, 2023
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Monitoring a suite of trace gases in the stratosphere will help us better understand the stratospheric circulation and its impact on the earth's radiation balance. However, such measurements are rare and usually expensive. We developed an instrument that can measure stratospheric trace gases using a low-cost sampling platform (AirCore). The results showed expected agreement with aircraft measurements, demonstrating this technique provides a low-cost and robust way to observe the stratosphere.
Tara I. Yacovitch, Christoph Dyroff, Joseph R. Roscioli, Conner Daube, J. Barry McManus, and Scott C. Herndon
Atmos. Meas. Tech., 16, 1915–1921, https://doi.org/10.5194/amt-16-1915-2023, https://doi.org/10.5194/amt-16-1915-2023, 2023
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Ethylene oxide is a toxic, carcinogenic compound used in the medical and bulk sterilization industry. Here we describe a precise and fast laser-based ethylene oxide monitor. We report months-long concentrations at a Massachusetts site, and we show how they suggest a potential emission source 35 km away. This source, and another, is confirmed by driving the instrument downwind of the sites, where concentrations were tens to tens of thousands of times greater than background levels.
Tatsumi Nakano and Takashi Morofuji
Atmos. Meas. Tech., 16, 1583–1595, https://doi.org/10.5194/amt-16-1583-2023, https://doi.org/10.5194/amt-16-1583-2023, 2023
Short summary
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We have developed a system that can automatically measure the pump efficiency of the ECC-type ozonesonde. Operational measurement for 13 years by this system revealed that the efficiency fluctuates in each and slightly increases over time. Those can affect the estimation of total ozone amount by up to 4 %. This result indicates that it is necessary to understand the tendency of the pump correction factor of each ozonesonde in order to detect the actual atmospheric change with high accuracy.
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Short summary
Atmospheric variations of helium (He) and CO2 are strongly linked due to the co-release of both gases from natural-gas burning. This implies that atmospheric He measurements may be a potentially powerful tool for verifying reported anthropogenic natural-gas usage. Here, we present the development and initial results of a novel measurement system of atmospheric He that paves the way for establishing a global monitoring network in the future.
Atmospheric variations of helium (He) and CO2 are strongly linked due to the co-release of both...
