Articles | Volume 26, issue 1
https://doi.org/10.5194/acp-26-723-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/acp-26-723-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Measurement report
| 
15 Jan 2026
Measurement report |
| 15 Jan 2026
| 15 Jan 2026
Measurement report: Isotopic composition of CH4 emitted from gas exploration sites in the Transylvanian Basin, Romania
Institute for Marine and Atmospheric Research Utrecht (IMAU), Utrecht University, Utrecht, the Netherlands
Malika Menoud
Institute for Marine and Atmospheric Research Utrecht (IMAU), Utrecht University, Utrecht, the Netherlands
now at: International Methane Emissions Observatory (IMEO), UNEP, Paris, France
Jacoline van Es
Institute for Marine and Atmospheric Research Utrecht (IMAU), Utrecht University, Utrecht, the Netherlands
Carina van der Veen
Institute for Marine and Atmospheric Research Utrecht (IMAU), Utrecht University, Utrecht, the Netherlands
Hossein Maazallahi
Institute for Marine and Atmospheric Research Utrecht (IMAU), Utrecht University, Utrecht, the Netherlands
now at: School of Energy and Sustainable Resources Engineering, College of Interdisciplinary Science and Technology, University of Tehran (UT), Tehran, Iran
Pawel Jagoda
Faculty of Physics and Applied Computer Science, AGH – University of Krakow, Krakow, Poland
Jaroslav M. Necki
Faculty of Physics and Applied Computer Science, AGH – University of Krakow, Krakow, Poland
Jakub Bartyzel
Faculty of Physics and Applied Computer Science, AGH – University of Krakow, Krakow, Poland
Piotr Korben
Faculty of Physics and Applied Computer Science, AGH – University of Krakow, Krakow, Poland
Institute of Environmental Physics, University of Heidelberg, Heidelberg, Germany
Sara Defratyka
Faculty of Physics and Applied Computer Science, AGH – University of Krakow, Krakow, Poland
now at: School of GeoSciences, University of Edinburgh, Edinburgh, UK
now at: National Physical Laboratory, Teddington, UK
Martina Schmidt
Institute of Environmental Physics, University of Heidelberg, Heidelberg, Germany
Marius Corbu
National Institute for Aerospace Research “Elie Carafoli” – INCAS, Bucharest, Romania
Faculty of Physics, University of Bucharest, Bucharest, Romania
Sebastian Iancu
National Institute for Aerospace Research “Elie Carafoli” – INCAS, Bucharest, Romania
Andreea Calcan
National Institute for Aerospace Research “Elie Carafoli” – INCAS, Bucharest, Romania
now at: International Methane Emissions Observatory (IMEO), UNEP, Paris, France
Magdalena Ardelean
National Institute for Aerospace Research “Elie Carafoli” – INCAS, Bucharest, Romania
Sorin Ghemulet
National Institute for Aerospace Research “Elie Carafoli” – INCAS, Bucharest, Romania
Cristian Pop
Faculty of Environmental Science and Engineering, Babes-Bolyai University, Cluj-Napoca, Romania
Andrei Radovici
Faculty of Environmental Science and Engineering, Babes-Bolyai University, Cluj-Napoca, Romania
Alexandru Mereuta
Faculty of Environmental Science and Engineering, Babes-Bolyai University, Cluj-Napoca, Romania
Horatiu Stefanie
Faculty of Environmental Science and Engineering, Babes-Bolyai University, Cluj-Napoca, Romania
Calin Baciu
Faculty of Environmental Science and Engineering, Babes-Bolyai University, Cluj-Napoca, Romania
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Jin Ma, Linda M. J. Kooijmans, Norbert Glatthor, Stephen A. Montzka, Marc von Hobe, Thomas Röckmann, and Maarten C. Krol
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Malavika Sivan, Thomas Röckmann, Carina van der Veen, and Maria Elena Popa
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Alina Fiehn, Maximilian Eckl, Julian Kostinek, Michał Gałkowski, Christoph Gerbig, Michael Rothe, Thomas Röckmann, Malika Menoud, Hossein Maazallahi, Martina Schmidt, Piotr Korbeń, Jarosław Neçki, Mila Stanisavljević, Justyna Swolkień, Andreas Fix, and Anke Roiger
Atmos. Chem. Phys., 23, 15749–15765, https://doi.org/10.5194/acp-23-15749-2023, https://doi.org/10.5194/acp-23-15749-2023, 2023
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Robbert P. J. Moonen, Getachew A. Adnew, Oscar K. Hartogensis, Jordi Vilà-Guerau de Arellano, David J. Bonell Fontas, and Thomas Röckmann
Atmos. Meas. Tech., 16, 5787–5810, https://doi.org/10.5194/amt-16-5787-2023, https://doi.org/10.5194/amt-16-5787-2023, 2023
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Atmos. Chem. Phys., 23, 14349–14357, https://doi.org/10.5194/acp-23-14349-2023, https://doi.org/10.5194/acp-23-14349-2023, 2023
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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.
Tim René de Groot, Anne Margriet Mol, Katherine Mesdag, Pierre Ramond, Rachel Ndhlovu, Julia Catherine Engelmann, Thomas Röckmann, and Helge Niemann
Biogeosciences, 20, 3857–3872, https://doi.org/10.5194/bg-20-3857-2023, https://doi.org/10.5194/bg-20-3857-2023, 2023
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This study investigates methane dynamics in the Wadden Sea. Our measurements revealed distinct variations triggered by seasonality and tidal forcing. The methane budget was higher in warmer seasons but surprisingly high in colder seasons. Methane dynamics were amplified during low tides, flushing the majority of methane into the North Sea or releasing it to the atmosphere. Methanotrophic activity was also elevated during low tide but mitigated only a small fraction of the methane efflux.
Foteini Stavropoulou, Katarina Vinković, Bert Kers, Marcel de Vries, Steven van Heuven, Piotr Korbeń, Martina Schmidt, Julia Wietzel, Pawel Jagoda, Jaroslav M. Necki, Jakub Bartyzel, Hossein Maazallahi, Malika Menoud, Carina van der Veen, Sylvia Walter, Béla Tuzson, Jonas Ravelid, Randulph Paulo Morales, Lukas Emmenegger, Dominik Brunner, Michael Steiner, Arjan Hensen, Ilona Velzeboer, Pim van den Bulk, Hugo Denier van der Gon, Antonio Delre, Maklawe Essonanawe Edjabou, Charlotte Scheutz, Marius Corbu, Sebastian Iancu, Denisa Moaca, Alin Scarlat, Alexandru Tudor, Ioana Vizireanu, Andreea Calcan, Magdalena Ardelean, Sorin Ghemulet, Alexandru Pana, Aurel Constantinescu, Lucian Cusa, Alexandru Nica, Calin Baciu, Cristian Pop, Andrei Radovici, Alexandru Mereuta, Horatiu Stefanie, Alexandru Dandocsi, Bas Hermans, Stefan Schwietzke, Daniel Zavala-Araiza, Huilin Chen, and Thomas Röckmann
Atmos. Chem. Phys., 23, 10399–10412, https://doi.org/10.5194/acp-23-10399-2023, https://doi.org/10.5194/acp-23-10399-2023, 2023
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In this study, we quantify CH4 emissions from onshore oil production sites in Romania at source and facility level using a combination of ground- and drone-based measurement techniques. We show that the total CH4 emissions in our studied areas are much higher than the emissions reported to UNFCCC, and up to three-quarters of the detected emissions are related to operational venting. Our results suggest that oil and gas production infrastructure in Romania holds a massive mitigation potential.
Andreas Forstmaier, Jia Chen, Florian Dietrich, Juan Bettinelli, Hossein Maazallahi, Carsten Schneider, Dominik Winkler, Xinxu Zhao, Taylor Jones, Carina van der Veen, Norman Wildmann, Moritz Makowski, Aydin Uzun, Friedrich Klappenbach, Hugo Denier van der Gon, Stefan Schwietzke, and Thomas Röckmann
Atmos. Chem. Phys., 23, 6897–6922, https://doi.org/10.5194/acp-23-6897-2023, https://doi.org/10.5194/acp-23-6897-2023, 2023
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Large cities emit greenhouse gases which contribute to global warming. In this study, we measured the release of one important green house gas, methane, in Hamburg. Multiple sources that contribute to methane emissions were located and quantified. Methane sources were found to be mainly caused by human activity (e.g., by release from oil and gas refineries). Moreover, potential natural sources have been located, such as the Elbe River and lakes.
Truls Andersen, Zhao Zhao, Marcel de Vries, Jaroslaw Necki, Justyna Swolkien, Malika Menoud, Thomas Röckmann, Anke Roiger, Andreas Fix, Wouter Peters, and Huilin Chen
Atmos. Chem. Phys., 23, 5191–5216, https://doi.org/10.5194/acp-23-5191-2023, https://doi.org/10.5194/acp-23-5191-2023, 2023
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The Upper Silesian Coal Basin, Poland, is one of the hot spots of methane emissions in Europe. Using an uncrewed aerial vehicle (UAV), we performed atmospheric measurements of methane concentrations downwind of five ventilation shafts in this region and determined the emission rates from the individual shafts. We found a strong correlation between quantified shaft-averaged emission rates and hourly inventory data, which also allows us to estimate the methane emissions from the entire region.
Bryce F. J. Kelly, Xinyi Lu, Stephen J. Harris, Bruno G. Neininger, Jorg M. Hacker, Stefan Schwietzke, Rebecca E. Fisher, James L. France, Euan G. Nisbet, David Lowry, Carina van der Veen, Malika Menoud, and Thomas Röckmann
Atmos. Chem. Phys., 22, 15527–15558, https://doi.org/10.5194/acp-22-15527-2022, https://doi.org/10.5194/acp-22-15527-2022, 2022
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This study explores using the composition of methane of in-flight atmospheric air samples for greenhouse gas inventory verification. The air samples were collected above one of the largest coal seam gas production regions in the world. Adjacent to these gas fields are coal mines, Australia's largest cattle feedlot, and over 1 million grazing cattle. The results are also used to identify methane mitigation opportunities.
Malika Menoud, Carina van der Veen, Dave Lowry, Julianne M. Fernandez, Semra Bakkaloglu, James L. France, Rebecca E. Fisher, Hossein Maazallahi, Mila Stanisavljević, Jarosław Nęcki, Katarina Vinkovic, Patryk Łakomiec, Janne Rinne, Piotr Korbeń, Martina Schmidt, Sara Defratyka, Camille Yver-Kwok, Truls Andersen, Huilin Chen, and Thomas Röckmann
Earth Syst. Sci. Data, 14, 4365–4386, https://doi.org/10.5194/essd-14-4365-2022, https://doi.org/10.5194/essd-14-4365-2022, 2022
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Emission sources of methane (CH4) can be distinguished with measurements of CH4 stable isotopes. We present new measurements of isotope signatures of various CH4 sources in Europe, mainly anthropogenic, sampled from 2017 to 2020. The present database also contains the most recent update of the global signature dataset from the literature. The dataset improves CH4 source attribution and the understanding of the global CH4 budget.
Stephen M. Platt, Øystein Hov, Torunn Berg, Knut Breivik, Sabine Eckhardt, Konstantinos Eleftheriadis, Nikolaos Evangeliou, Markus Fiebig, Rebecca Fisher, Georg Hansen, Hans-Christen Hansson, Jost Heintzenberg, Ove Hermansen, Dominic Heslin-Rees, Kim Holmén, Stephen Hudson, Roland Kallenborn, Radovan Krejci, Terje Krognes, Steinar Larssen, David Lowry, Cathrine Lund Myhre, Chris Lunder, Euan Nisbet, Pernilla B. Nizzetto, Ki-Tae Park, Christina A. Pedersen, Katrine Aspmo Pfaffhuber, Thomas Röckmann, Norbert Schmidbauer, Sverre Solberg, Andreas Stohl, Johan Ström, Tove Svendby, Peter Tunved, Kjersti Tørnkvist, Carina van der Veen, Stergios Vratolis, Young Jun Yoon, Karl Espen Yttri, Paul Zieger, Wenche Aas, and Kjetil Tørseth
Atmos. Chem. Phys., 22, 3321–3369, https://doi.org/10.5194/acp-22-3321-2022, https://doi.org/10.5194/acp-22-3321-2022, 2022
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Here we detail the history of the Zeppelin Observatory, a unique global background site and one of only a few in the high Arctic. We present long-term time series of up to 30 years of atmospheric components and atmospheric transport phenomena. Many of these time series are important to our understanding of Arctic and global atmospheric composition change. Finally, we discuss the future of the Zeppelin Observatory and emerging areas of future research on the Arctic atmosphere.
Juhi Nagori, Narcisa Nechita-Bândă, Sebastian Oscar Danielache, Masumi Shinkai, Thomas Röckmann, and Maarten Krol
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2022-68, https://doi.org/10.5194/acp-2022-68, 2022
Publication in ACP not foreseen
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The sulfur isotopes (32S and 34S) were studied to understand the sources, sinks and processes of carbonyl sulphide (COS) in the atmosphere. COS is an important source of sulfur aerosol in the stratosphere (SSA). Few measurements of COS and SSA exist, but with our 1D model, we were able to match them and show the importance of COS to sulfate formation. Moreover, we are able to highlight some important processes for the COS budget and where measurements may fill a gap in current knowledge.
Malika Menoud, Carina van der Veen, Jaroslaw Necki, Jakub Bartyzel, Barbara Szénási, Mila Stanisavljević, Isabelle Pison, Philippe Bousquet, and Thomas Röckmann
Atmos. Chem. Phys., 21, 13167–13185, https://doi.org/10.5194/acp-21-13167-2021, https://doi.org/10.5194/acp-21-13167-2021, 2021
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Using measurements of methane isotopes in ambient air and a 3D atmospheric transport model, in Krakow, Poland, we mainly detected fossil-fuel-related sources, coming from coal mining in Silesia and from the use of natural gas in the city. Emission inventories report large emissions from coal mine activity in Silesia, which is in agreement with our measurements. However, methane sources in the urban area of Krakow related to the use of fossil fuels might be underestimated in the inventories.
Stephen J. Harris, Sven Krautwurst, Jorg Hacker, Mark Lunt, Jakob Borchardt, Mei Bai, Hartmut Boesch, Tarra Brain, John Philip Burrows, Shakti Chakravarty, Robert A. Field, Rebecca E. Fisher, James L. France, Konstantin Gerilowski, Oke Huhs, Wolfgang Junkermann, Bryce F. J. Kelly, Martin Kumm, Mathias Lanoisellé, Wolfgang Lieff, Andrew McGrath, Adrian Murphy, Thomas Röckmann, Zoe Salmon, Josua Schindewolf, Jakob Thoböll, Carina van der Veen, and Heinrich Bovensmann
Atmos. Chem. Phys., 26, 10043–10069, https://doi.org/10.5194/acp-26-10043-2026, https://doi.org/10.5194/acp-26-10043-2026, 2026
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The accuracy of methods used to estimate and report fugitive methane emissions from Australian coal mines remains unclear. This study compares airborne emission rate estimates with reported estimates from 17 coal mines in the Bowen Basin, a region accounting for 45 % of national coal production. Results show good agreement for underground coal mines, but poor agreement for surface coal mines, suggesting improvements to surface coal mine reporting methods is needed to improve inventory reporting.
Audrey McManemin, Catherine Juéry, Vincent Blandin, Matthew Baker, Stéphane Bauguitte, Dominik Brunner, Philippine Burdeau, James Lawrence France, Anders M. Fredenslund, Andreas Hueni, Gerrit Kuhlmann, Patryk Łakomiec, Sando Meier, Roberto Paglini, Roubina Papaconstantinou, Jean-Daniel Paris, Pierre-Yves Quehe, Thomas Röckmann, Charlotte Scheutz, Martina Schmidt, Marius Vögtli, Julia B. Wietzel, and Adam R. Brandt
EGUsphere, https://doi.org/10.5194/egusphere-2026-1744, https://doi.org/10.5194/egusphere-2026-1744, 2026
This preprint is open for discussion and under review for Atmospheric Measurement Techniques (AMT).
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Researchers tested five university-led systems to measure methane leaks at a facility in France. By releasing known amounts of gas, researchers checked if mobile tools on vehicles and planes could accurately detect and quantify emissions. Most sensors were excellent at finding leaks, but their accuracy in measuring the exact emission rate varied. Weather, especially low wind, significantly impacted results. These findings help improve how we track greenhouse gases to meet climate goals.
Emeline Tapin, Antoine Berchet, Adrien Martinez, Malika Menoud, Joël Thanwerdas, Xin Lan, Edward Malina, Daniele Gasbarra, and Marielle Saunois
Earth Syst. Sci. Data, 18, 4793–4832, https://doi.org/10.5194/essd-18-4793-2026, https://doi.org/10.5194/essd-18-4793-2026, 2026
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We present global δ¹³C-CH₄ source signature maps (1998–2022) at 1°×1° resolution for five emission sectors and 11 sub-sectors, with quantified uncertainties. Sensitivity experiments with an atmospheric transport model assess how uncertainties in emissions, isotopic signatures, OH sinks, and kinetic isotope effects influence atmospheric δ¹³C-CH₄ and CH₄, providing guidance for isotopic inversions.
Bibhasvata Dasgupta, Sudhanshu Pandey, Sander Houweling, Malika Menoud, Carina van der Veen, John Miller, Ben Riddell-Young, Sylvia Englund Michel, Peter Sperlich, Shinji Morimoto, Ryo Fujita, Stephen Platt, Christine Groot Zwaaftink, Ingeborg Levin, Cordelia Veidt, Cathrine Lund Myhre, Ceres Woolley Maisch, Rebecca Fisher, Euan G. Nisbet, James France, Rowena Moss, Nicola Warwick, and Thomas Röckmann
Atmos. Chem. Phys., 26, 8601–8616, https://doi.org/10.5194/acp-26-8601-2026, https://doi.org/10.5194/acp-26-8601-2026, 2026
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Methane is a strong greenhouse gas, and its rise since the mid-2000s is debated in terms of sources and sinks. Using top-down and bottom-up data, along with inversion models and methane isotopes (δ13C-CH4 and δD-CH4), we find that wetlands are the primary driver of post-2006 increases, followed by agriculture and fossil fuels. Methane's lifetime has decreased by about 0.1 years. We also assess how isotope signatures and sink processes influence uncertainties.
Lison Soussaintjean, Jochen Schmitt, Joël Savarino, J. Andy Menking, Edward J. Brook, Barbara Seth, Vladimir Lipenkov, Thomas Röckmann, and Hubertus Fischer
Biogeosciences, 23, 3939–3963, https://doi.org/10.5194/bg-23-3939-2026, https://doi.org/10.5194/bg-23-3939-2026, 2026
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Nitrous oxide (N2O) produced in dust-rich Antarctic ice complicates the reconstruction of past atmospheric levels from ice core records. Using isotope analysis, we show that N2O forms from two nitrogen precursors, one being nitrate. For the first time, we demonstrate that the site preference (SP) of N2O reflects the isotopic difference between these precursors, not the production pathway, which challenges the common interpretation of SP.
Liang Feng, Paul I. Palmer, Haolin Wang, Robert Parker, Hartmut Boesch, Sébastien C. Biraud, Łukasz Chmura, Emanuel Gloor, László Haszpra, Elena Kozlova, Euan G. Nisbet, Steffen M. Noe, Thomas Röckmann, Rodrigo Augusto Ferreira de Souza, and Martin Steinbacher
EGUsphere, https://doi.org/10.5194/egusphere-2026-2662, https://doi.org/10.5194/egusphere-2026-2662, 2026
This preprint is open for discussion and under review for Atmospheric Chemistry and Physics (ACP).
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This study examines the relative roles of emissions and oxidation in recent rapid methane growth. Using an ensemble Kalman filter, we quantify global methane sources and sinks for 2018–2024. Emission changes dominate the increase, except in 2020 when a COVID‑19‑related OH decline strongly affected sinks. Atmospheric photochemistry—including OH and CH₄ variability and temperature‑dependent oxidation—also significantly shapes the methane budget.
Mirosław Zimnoch, Michał Gałkowski, Piotr Sekula, Łukasz Chmura, Jakub Bartyzel, Alina Jasek-Kamińska, Alicja Skiba, Jarosław Nęcki, Paweł Jagoda, Michał Kud, and Przemysław Wachniew
Atmos. Chem. Phys., 26, 7061–7080, https://doi.org/10.5194/acp-26-7061-2026, https://doi.org/10.5194/acp-26-7061-2026, 2026
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The manuscript presents the dataset collected in the urban area of Krakow city containing several measurement campaigns focused on the investigation of vertical CO2 and CH4 profiles supplemented by set of meteorological parameters (e.g. temperature, pressure) measured along the profiles up to ca. 280 m a.g.l. The presented data collection explains the dynamics of the lower atmosphere on a daily and seasonal scale providing the three dimensional dataset that can be used for model validation.
Jacoline van Es, Juan Bettinelli, Jia Chen, Carina van der Veen, Stephan Henne, and Thomas Röckmann
EGUsphere, https://doi.org/10.5194/egusphere-2026-1813, https://doi.org/10.5194/egusphere-2026-1813, 2026
This preprint is open for discussion and under review for Atmospheric Chemistry and Physics (ACP).
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The increase in atmospheric methane needs to be reversed to mitigate ongoing global warming. To design effective mitigation strategies at the local/regional level, we need to know what the main sources in different regions. We show that in Hamburg, Germany, biogenic sources are the main contributor to local emissions, with additional contributions from waste and fossil CH4 sources. An unexpected source is the Elbe River, with spiking emissions at low tide when the river banks are exposed.
Elinor C. Tuffnell, Emma Leedham-Elvidge, William T. Sturges, Harald Bönisch, Karina E. Adcock, Paul J. Fraser, Paul B. Krummel, David E. Oram, Ray L. Langenfelds, Thomas Röckmann, Luke M. Western, Jens Mühle, and Johannes C. Laube
Atmos. Chem. Phys., 26, 4583–4599, https://doi.org/10.5194/acp-26-4583-2026, https://doi.org/10.5194/acp-26-4583-2026, 2026
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The greater the stratospheric lifetime of chlorofluorocarbons (CFCs), the longer they will deplete ozone. This paper investigates four longer-lived CFCs, and discovers two of them have much shorter lifetimes than previously believed. Demonstrating emissions of these compounds are higher than assumed, to account for their abundance. Unusually this paper uses stratospheric whole-air samples, rather than models or lab-based experiments, to derive policy-relevant metrics for these compounds.
Annalisa Delre, Thomas Röckmann, David J. Bonell Fontas, Julia C. Engelmann, and Helge Niemann
EGUsphere, https://doi.org/10.5194/egusphere-2026-1582, https://doi.org/10.5194/egusphere-2026-1582, 2026
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Estuaries are important natural sources of methane, a greenhouse gas that affects climate. We studied how methane changes along the Scheldt estuary by measuring gas concentrations, carbon isotopes and identification and quantification of methane oxidizing bacteria. We found that methane levels varied strongly and were not mainly controlled by salinity. Most methane escaped to the atmosphere, showing that estuaries may contribute more to climate change than previously thought.
Julian Großmann, Frank Meinhardt, Antje Hoheisel, Bryan Hellack, and Martina Schmidt
EGUsphere, https://doi.org/10.5194/egusphere-2026-849, https://doi.org/10.5194/egusphere-2026-849, 2026
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Long-term measurements of atmospheric CO2 have been conducted at Schauinsland station in southwest Germany since 1972. In order possibly to relocate the air intake line from 12 m to 35 m above ground, we compared three years of parallel CO2 and CH4 measurements. We find systematic differences in diurnal and seasonal variations for CO2, but not for CH4. The results of our study indicate that measurements should be taken at both heights to ensure consistency with historical records.
Sarah E. Hancock, Daniel J. Jacob, Rodrigo Jimenez, Andrés Ardila, Luis Morales-Rincon, Néstor Rojas, Lucas A. Estrada, Nicholas Balasus, James D. East, Melissa P. Sulprizio, Xiaolin Wang, James L. France, Lauren Potyk, Elise Penn, Zichong Chen, Daniel J. Varon, Christian Frankenberg, Marci Baranski, Andreea Calcan, and Robert J. Parker
EGUsphere, https://doi.org/10.5194/egusphere-2025-5478, https://doi.org/10.5194/egusphere-2025-5478, 2026
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We combined satellite observations with detailed national data to improve estimates of Colombia’s methane emissions. Our results show that total methane emissions are higher than reported, with the biggest differences from fossil fuels. This approach demonstrates how satellite data can make national greenhouse gas reporting more accurate and transparent under the Paris Agreement.
Gianluca Di Natale, Helen Brindley, Laura Warwick, Sanjeevani Panditharatne, Ping Yang, Robert Oscar David, Tim Carlsen, Sorin Nicolae Vâjâiac, Alex Vlad, Sorin Ghemuleț, Richard Bantges, Andreas Foth, Martin Flügge, Reidar Lyngra, Hilke Oetjen, Dirk Schuettemeyer, Luca Palchetti, and Jonathan Murray
Atmos. Chem. Phys., 26, 1373–1394, https://doi.org/10.5194/acp-26-1373-2026, https://doi.org/10.5194/acp-26-1373-2026, 2026
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Cirrus clouds play a vital role in regulating Earth's energy balance. However, they remain incompletely understood, representing a major source of uncertainty in the predictive performance of climate models. We show that consistency between in situ measurements of cirrus cloud microphysics and ground-based remote sensing observations is achievable by simulating the emitted spectrum using current parameterizations of cirrus optical properties.
Lisa Ardoin, Catherine Larose, Jean-Louis Tison, Christoph Keuschnig, Vasileios Gkinis, Saïda El Amri, Pierre-Henry Blard, Paul Bierman, Thomas Blunier, Dorthe Dahl-Jensen, Charlotte Maistriau, Jørgen-Peder Steffensen, Thomas Röckmann, and François Fripiat
EGUsphere, https://doi.org/10.5194/egusphere-2025-6204, https://doi.org/10.5194/egusphere-2025-6204, 2026
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We investigated gas dynamics at the ice–bed interface of two Greenland ice cores to assess methane and carbon dioxide behaviour beneath ice sheets. At Camp Century, methane diffuses into the ice and is partly oxidized. At GRIP, methane remains preserved despite oxygen. These contrasts suggest that methane oxidation is controlled by local basal conditions, including ice thickness and substrate availability.
Paul Waldmann, Max Eckl, Leon Knez, Klaus-Dirk Gottschaldt, Alina Fiehn, Christian Mallaun, Michał Gałkowski, Christoph Kiemle, Ronald Hutjes, Thomas Röckmann, Huilin Chen, and Anke Roiger
Atmos. Meas. Tech., 19, 185–210, https://doi.org/10.5194/amt-19-185-2026, https://doi.org/10.5194/amt-19-185-2026, 2026
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Nitrous oxide and methane emissions from agriculture need to be reduced, therefore emissions must be understood to effectively mitigate them. This is the first approach to measure those emissions aircraft-based, to assess their magnitude and drivers. We identified emission hotspots and temporal changes in agricultural emissions in the Netherlands. Our approach is applicable to further greenhouse gas emitters, therefore it builds a step towards more comprehensive emission quantification.
Robbert P. J. Moonen, Getachew A. Adnew, Jordi Vilà-Guerau de Arellano, David J. Bonell Fontas, and Thomas Röckmann
EGUsphere, https://doi.org/10.5194/egusphere-2025-5969, https://doi.org/10.5194/egusphere-2025-5969, 2025
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We used high-frequency H₂O and CO₂ isotope measurements at ATTO to separate water vapour and carbon dioxide fluxes into their component processes. During midday, ~95 % of evapotranspiration came from plant transpiration. Isotopes also revealed the balance between photosynthesis and respiration, showing strong sensitivity to leaf CO₂ ratios. These results improve understanding of Amazon ecosystem function.
Sara M. Defratyka, Julianne M. Fernandez, Getachew A. Adnew, Guannan Dong, Peter M. J. Douglas, Daniel L. Eldridge, Giuseppe Etiope, Thomas Giunta, Mojhgan A. Haghnegahdar, Alexander N. Hristov, Nicole Hultquist, Iñaki Vadillo, Josue Jautzy, Ji-Hyun Kim, Jabrane Labidi, Ellen Lalk, Wil Leavitt, Jiawen Li, Li-Hung Lin, Jiarui Liu, Lucía Ojeda, Shuhei Ono, Jeemin H. Rhim, Thomas Röckmann, Barbara Sherwood Lollar, Malavika Sivan, Jiayang Sun, Gregory T. Ventura, David T. Wang, Edward D. Young, Naizhong Zhang, and Tim Arnold
Earth Syst. Sci. Data, 17, 6889–6910, https://doi.org/10.5194/essd-17-6889-2025, https://doi.org/10.5194/essd-17-6889-2025, 2025
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Measurement of methane’s doubly substituted isotopologues at natural abundances holds promise for better constraining the Earth’s atmospheric CH4 budget. We compiled 1475 measurements from field samples and laboratory experiments, conducted since 2014, to facilitate the differentiation of CH4 formation pathways and processes, to identify existing gaps limiting application of Δ13CH3D and Δ12CH2D2, and to develop isotope ratio source signature inputs for global CH4 flux modelling.
Eric Förster, Heidi Huntrieser, Michael Lichtenstern, Falk Pätzold, Lutz Bretschneider, Andreas Schlerf, Sven Bollmann, Astrid Lampert, Jarosław Nęcki, Paweł Jagoda, Justyna Swolkień, Dominika Pasternak, Robert A. Field, and Anke Roiger
Atmos. Meas. Tech., 18, 7153–7176, https://doi.org/10.5194/amt-18-7153-2025, https://doi.org/10.5194/amt-18-7153-2025, 2025
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We introduce a helicopter-borne mass balance approach, utilizing the HELiPOD platform, to accurately quantify methane (CH4) emissions from coal mining activities. The comparison of our top-down mass flux estimates (up to 3000 kg h−1) against those from bottom-up in-mine CH4 safety sensors revealed very good agreement. This approach also has a great potential in quantifying emission source strengths (down to 20 kg h−1) from a wide range of other CH4 emitters (e.g. landfills, oil & gas industry).
Bibhasvata Dasgupta, Malika Menoud, Carina van der Veen, Ingeborg Levin, Cordelia Veidt, Heiko Moossen, Sylvia Englund Michel, Peter Sperlich, Shinji Morimoto, Ryo Fujita, Taku Umezawa, Stephen Platt, Christine Groot Zwaaftink, Cathrine Lund Myhre, Rebecca Fisher, David Lowry, Euan G. Nisbet, James France, Ceres Woolley Maisch, Gordon Brailsford, Rowena Moss, Daisuke Goto, Sudhanshu Pandey, Sander Houweling, Nicola Warwick, and Thomas Röckmann
Atmos. Meas. Tech., 18, 6591–6607, https://doi.org/10.5194/amt-18-6591-2025, https://doi.org/10.5194/amt-18-6591-2025, 2025
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We combined long-term methane mole fraction and isotope measurements from eight laboratories that sample high-latitude stations to compare, offset correct and harmonise the datasets into a hemisphere merged timeseries. Because each laboratory uses slightly different methods, we adjusted the data to make it directly comparable. This allowed us to create a consistent record of atmospheric methane concentration and its isotopes from 1988 to 2023.
Martina Schmidt, Ingeborg Bussmann, Sarah Johanna Ernestina Reith, Annika Palzer, Cedric Couret, Frank Keppler, Daniela Polag, Lasse Sander, Moritz Schroll, and Julia B. Wietzel
EGUsphere, https://doi.org/10.5194/egusphere-2025-4850, https://doi.org/10.5194/egusphere-2025-4850, 2025
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Methane (CH4) measurements near a sand dredging site off Sylt (North Sea) revealed elevated concentrations in both air and water, particularly during summer. CH4 fluxes were significantly higher at the dredging site compared to surrounding areas. Isotopic signatures suggest a microbial origin. These findings indicate that coastal sand extraction may represent a previously unaccounted source of atmospheric CH4.
Sophie L. Baartman, Steven M. Driever, Maarten L. J. Wassenaar, Linda M. J. Kooijmans, Nerea Ubierna, Leon Mossink, Maria E. Popa, Ara Cho, Lisa Wingate, Thomas Röckmann, Steven M. A. C. van Heuven, and Maarten C. Krol
Biogeosciences, 22, 5683–5703, https://doi.org/10.5194/bg-22-5683-2025, https://doi.org/10.5194/bg-22-5683-2025, 2025
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Carbonyl sulfide (COS) is a proposed tracer for gross primary production. For the first time, COS and carbon dioxide (CO2) uptake fluxes and isotope discrimination were jointly measured in sunflower and papyrus plants, using a flow-through plant chamber approach and varying light availability. COS isotope discrimination did not differ significantly between the species, nor with changes in light. CO2 fluxes and isotope values provided additional valuable information for data interpretation.
Robbert P. J. Moonen, Getachew A. Adnew, Jordi Vilà-Guerau de Arellano, Oscar K. Hartogensis, David J. Bonell Fontas, Shujiro Komiya, Sam P. Jones, and Thomas Röckmann
Atmos. Chem. Phys., 25, 12197–12212, https://doi.org/10.5194/acp-25-12197-2025, https://doi.org/10.5194/acp-25-12197-2025, 2025
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Understory ejections are distinct turbulent features emerging in prime tall-forest ecosystems. We share a method to isolate understory ejections based on H2O–CO2 anomaly quadrants. From these, we calculate the flux contributions of understory ejections and all flux quadrants. In addition, we show that a distinctly depleted isotopic composition can be found in the ejected water vapour. Finally, we explored the role of clouds as a potential trigger for understory ejections.
Julia Beate Wietzel, Piotr Korben, Antje Hoheisel, and Martina Schmidt
Atmos. Meas. Tech., 18, 4631–4645, https://doi.org/10.5194/amt-18-4631-2025, https://doi.org/10.5194/amt-18-4631-2025, 2025
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Long-term measurements of CH4 emission rates at a biogas plant in Germany were performed for eight years using mobile measurements combined with a Gaussian plume model. The average CH4 emission rate of the biogas plant was 5.9 ± 0.5 kg CH4 h-1. To increase the accuracy of the emission rate calculations and harmonize the dataset, the methodology was evaluated through six controlled methane release experiments demonstrating an uncertainty lower than 30 %, following several recommendations.
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.
Yosuke Niwa, Yasunori Tohjima, Yukio Terao, Tazu Saeki, Akihiko Ito, Taku Umezawa, Kyohei Yamada, Motoki Sasakawa, Toshinobu Machida, Shin-Ichiro Nakaoka, Hideki Nara, Hiroshi Tanimoto, Hitoshi Mukai, Yukio Yoshida, Shinji Morimoto, Shinya Takatsuji, Kazuhiro Tsuboi, Yousuke Sawa, Hidekazu Matsueda, Kentaro Ishijima, Ryo Fujita, Daisuke Goto, Xin Lan, Kenneth Schuldt, Michal Heliasz, Tobias Biermann, Lukasz Chmura, Jarsolaw Necki, Irène Xueref-Remy, and Damiano Sferlazzo
Atmos. Chem. Phys., 25, 6757–6785, https://doi.org/10.5194/acp-25-6757-2025, https://doi.org/10.5194/acp-25-6757-2025, 2025
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This study estimated regional and sectoral emission contributions to the unprecedented surge of atmospheric methane for 2020–2022. The methane is the second most important greenhouse gas, and its emissions reduction is urgently required to mitigate global warming. Numerical modeling-based estimates with three different sets of atmospheric observations consistently suggested large contributions of biogenic emissions from South Asia and Southeast Asia to the surge of atmospheric methane.
Getachew Agmuas Adnew, Gerbrand Koren, Neha Mehendale, Sergey Gromov, Maarten Krol, and Thomas Röckmann
Atmos. Meas. Tech., 18, 2701–2719, https://doi.org/10.5194/amt-18-2701-2025, https://doi.org/10.5194/amt-18-2701-2025, 2025
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This study presents high-precision measurements of ∆′17O(CO2). Key findings include the extension of the N2O–∆′17O correlation to the upper troposphere and the identification of significant differences in the N2O–∆′17O slope in StratoClim samples. Additionally, the ∆′17O measurements are used to estimate global stratospheric production and surface removal of ∆′17O, providing an independent estimate of global vegetation CO2 exchange.
Gerrit Kuhlmann, Foteini Stavropoulou, Stefan Schwietzke, Daniel Zavala-Araiza, Andrew Thorpe, Andreas Hueni, Lukas Emmenegger, Andreea Calcan, Thomas Röckmann, and Dominik Brunner
Atmos. Chem. Phys., 25, 5371–5385, https://doi.org/10.5194/acp-25-5371-2025, https://doi.org/10.5194/acp-25-5371-2025, 2025
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A measurement campaign in 2019 found that methane emissions from oil and gas in Romania were significantly higher than reported. In 2021, our follow-up campaign using airborne remote sensing showed a marked decreases in emissions by 20 %–60 % due to improved infrastructure. The study highlights the importance of measurement-based emission monitoring and illustrates the value of a multi-scale assessment integrating ground-based observations with large-scale airborne remote sensing campaigns.
Tanja J. Schuck, Johannes Degen, Timo Keber, Katharina Meixner, Thomas Wagenhäuser, Mélanie Ghysels, Georges Durry, Nadir Amarouche, Alessandro Zanchetta, Steven van Heuven, Huilin Chen, Johannes C. Laube, Sophie L. Baartman, Carina van der Veen, Maria Elena Popa, and Andreas Engel
Atmos. Chem. Phys., 25, 4333–4348, https://doi.org/10.5194/acp-25-4333-2025, https://doi.org/10.5194/acp-25-4333-2025, 2025
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A balloon was launched in 2021 in the Arctic to carry instruments for trace gas measurements up to 32 km. One purpose was to compare measurement techniques. We focus on the major greenhouse gases. To measure these, air was sampled with the AirCore technique and with flask sampling, and samples were analysed after the flight. In flight, observations were done with an optical method. In a companion paper, we report on observations of chlorine and bromine containing trace gases.
Hector Navarro-Barboza, Jordi Rovira, Vincenzo Obiso, Andrea Pozzer, Marta Via, Andres Alastuey, Xavier Querol, Noemi Perez, Marjan Savadkoohi, Gang Chen, Jesus Yus-Díez, Matic Ivancic, Martin Rigler, Konstantinos Eleftheriadis, Stergios Vratolis, Olga Zografou, Maria Gini, Benjamin Chazeau, Nicolas Marchand, Andre S. H. Prevot, Kaspar Dallenbach, Mikael Ehn, Krista Luoma, Tuukka Petäjä, Anna Tobler, Jaroslaw Necki, Minna Aurela, Hilkka Timonen, Jarkko Niemi, Olivier Favez, Jean-Eudes Petit, Jean-Philippe Putaud, Christoph Hueglin, Nicolas Pascal, Aurélien Chauvigné, Sébastien Conil, Marco Pandolfi, and Oriol Jorba
Atmos. Chem. Phys., 25, 2667–2694, https://doi.org/10.5194/acp-25-2667-2025, https://doi.org/10.5194/acp-25-2667-2025, 2025
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Brown carbon (BrC) absorbs ultraviolet (UV) and visible light, influencing climate. This study explores BrC's imaginary refractive index (k) using data from 12 European sites. Residential emissions are a major organic aerosol (OA) source in winter, while secondary organic aerosol (SOA) dominates in summer. Source-specific k values were derived, improving model accuracy. The findings highlight BrC's climate impact and emphasize source-specific constraints in atmospheric models.
Hossein Maazallahi, Foteini Stavropoulou, Samuel Jonson Sutanto, Michael Steiner, Dominik Brunner, Mariano Mertens, Patrick Jöckel, Antoon Visschedijk, Hugo Denier van der Gon, Stijn Dellaert, Nataly Velandia Salinas, Stefan Schwietzke, Daniel Zavala-Araiza, Sorin Ghemulet, Alexandru Pana, Magdalena Ardelean, Marius Corbu, Andreea Calcan, Stephen A. Conley, Mackenzie L. Smith, and Thomas Röckmann
Atmos. Chem. Phys., 25, 1497–1511, https://doi.org/10.5194/acp-25-1497-2025, https://doi.org/10.5194/acp-25-1497-2025, 2025
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This article presents insights from airborne in situ measurements collected during the ROmanian Methane Emissions from Oil and gas (ROMEO) campaign supported by two models. Results reveal Romania's oil and gas methane emissions were significantly under-reported to the United Nations Framework Convention on Climate Change (UNFCCC) in 2019. A large underestimation was also found in the Emissions Database for Global Atmospheric Research (EDGAR) v7.0 for the study domain in the same year.
Hella van Asperen, Thorsten Warneke, Alessandro Carioca de Araújo, Bruce Forsberg, Sávio José Filgueiras Ferreira, Thomas Röckmann, Carina van der Veen, Sipko Bulthuis, Leonardo Ramos de Oliveira, Thiago de Lima Xavier, Jailson da Mata, Marta de Oliveira Sá, Paulo Ricardo Teixeira, Julie Andrews de França e Silva, Susan Trumbore, and Justus Notholt
Biogeosciences, 21, 3183–3199, https://doi.org/10.5194/bg-21-3183-2024, https://doi.org/10.5194/bg-21-3183-2024, 2024
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Carbon monoxide (CO) is regarded as an important indirect greenhouse gas. Soils can emit and take up CO, but, until now, uncertainty remains as to which process dominates in tropical rainforests. We present the first soil CO flux measurements from a tropical rainforest. Based on our observations, we report that tropical rainforest soils are a net source of CO. In addition, we show that valley streams and inundated areas are likely additional hot spots of CO in the ecosystem.
Jin Ma, Linda M. J. Kooijmans, Norbert Glatthor, Stephen A. Montzka, Marc von Hobe, Thomas Röckmann, and Maarten C. Krol
Atmos. Chem. Phys., 24, 6047–6070, https://doi.org/10.5194/acp-24-6047-2024, https://doi.org/10.5194/acp-24-6047-2024, 2024
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The global budget of atmospheric COS can be optimised by inverse modelling using TM5-4DVAR, with the co-constraints of NOAA surface observations and MIPAS satellite data. We found reduced COS biosphere uptake from inversions and improved land and ocean separation using MIPAS satellite data assimilation. Further improvements are expected from better quantification of COS ocean and biosphere fluxes.
Katrine A. Gorham, Sam Abernethy, Tyler R. Jones, Peter Hess, Natalie M. Mahowald, Daphne Meidan, Matthew S. Johnson, Maarten M. J. W. van Herpen, Yangyang Xu, Alfonso Saiz-Lopez, Thomas Röckmann, Chloe A. Brashear, Erika Reinhardt, and David Mann
Atmos. Chem. Phys., 24, 5659–5670, https://doi.org/10.5194/acp-24-5659-2024, https://doi.org/10.5194/acp-24-5659-2024, 2024
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Rapid reduction in atmospheric methane is needed to slow the rate of global warming. Reducing anthropogenic methane emissions is a top priority. However, atmospheric methane is also impacted by rising natural emissions and changing sinks. Studies of possible atmospheric methane removal approaches, such as iron salt aerosols to increase the chlorine radical sink, benefit from a roadmapped approach to understand if there may be viable and socially acceptable ways to decrease future risk.
Malavika Sivan, Thomas Röckmann, Carina van der Veen, and Maria Elena Popa
Atmos. Meas. Tech., 17, 2687–2705, https://doi.org/10.5194/amt-17-2687-2024, https://doi.org/10.5194/amt-17-2687-2024, 2024
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We have set up a measurement system for methane-clumped isotopologues. We have built an extraction and purification system to extract pure methane for these measurements, for samples of various origins, including atmospheric air, for which we need to process about 1000 L of air for one measurement. We report here the technical setup for extraction and measurements, as well as the calibration, and we give an overview of the samples measured so far.
Antje Hoheisel and Martina Schmidt
Atmos. Chem. Phys., 24, 2951–2969, https://doi.org/10.5194/acp-24-2951-2024, https://doi.org/10.5194/acp-24-2951-2024, 2024
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In Heidelberg, Germany, methane and its stable carbon isotope composition have been measured continuously with a cavity ring-down spectroscopy (CRDS) analyser since April 2014. These 6-year time series are analysed with the Keeling plot method for the isotopic composition of the sources, as well as seasonal variations and trends in methane emissions. The source contributions derived from atmospheric measurements were used to evaluate global and regional emission inventories of methane.
Pramod Kumar, Christopher Caldow, Grégoire Broquet, Adil Shah, Olivier Laurent, Camille Yver-Kwok, Sebastien Ars, Sara Defratyka, Susan Warao Gichuki, Luc Lienhardt, Mathis Lozano, Jean-Daniel Paris, Felix Vogel, Caroline Bouchet, Elisa Allegrini, Robert Kelly, Catherine Juery, and Philippe Ciais
Atmos. Meas. Tech., 17, 1229–1250, https://doi.org/10.5194/amt-17-1229-2024, https://doi.org/10.5194/amt-17-1229-2024, 2024
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This study presents a series of mobile measurement campaigns to monitor the CH4 emissions from an active landfill. These measurements are processed using a Gaussian plume model and atmospheric inversion techniques to quantify the landfill CH4 emissions. The methane emission estimates range between ~0.4 and ~7 t CH4 per day, and their variations are analyzed. The robustness of the estimates is assessed depending on the distance of the measurements from the potential sources in the landfill.
Alina Fiehn, Maximilian Eckl, Julian Kostinek, Michał Gałkowski, Christoph Gerbig, Michael Rothe, Thomas Röckmann, Malika Menoud, Hossein Maazallahi, Martina Schmidt, Piotr Korbeń, Jarosław Neçki, Mila Stanisavljević, Justyna Swolkień, Andreas Fix, and Anke Roiger
Atmos. Chem. Phys., 23, 15749–15765, https://doi.org/10.5194/acp-23-15749-2023, https://doi.org/10.5194/acp-23-15749-2023, 2023
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During the CoMet mission in the Upper Silesian Coal Basin (USCB) ground-based and airborne air samples were taken and analyzed for the isotopic composition of CH4 to derive the mean signature of the USCB and source signatures of individual coal mines. Using δ2H signatures, the biogenic emissions from the USCB account for 15 %–50 % of total emissions, which is underestimated in common emission inventories. This demonstrates the importance of δ2H-CH4 observations for methane source apportionment.
Tobias D. Schmitt, Jonas Kuhn, Ralph Kleinschek, Benedikt A. Löw, Stefan Schmitt, William Cranton, Martina Schmidt, Sanam N. Vardag, Frank Hase, David W. T. Griffith, and André Butz
Atmos. Meas. Tech., 16, 6097–6110, https://doi.org/10.5194/amt-16-6097-2023, https://doi.org/10.5194/amt-16-6097-2023, 2023
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Our new observatory measures greenhouse gas concentrations of carbon dioxide (CO2) and methane (CH4) along a 1.55 km long light path over the city of Heidelberg, Germany. We compared our measurements with measurements that were taken at a single point at one end of our path. The two mostly agreed but show a significant difference for CO2 with certain wind directions. This is important when using greenhouse gas concentration measurements to observe greenhouse gas emissions of cities.
Douglas E. J. Worthy, Michele K. Rauh, Lin Huang, Felix R. Vogel, Alina Chivulescu, Kenneth A. Masarie, Ray L. Langenfelds, Paul B. Krummel, Colin E. Allison, Andrew M. Crotwell, Monica Madronich, Gabrielle Pétron, Ingeborg Levin, Samuel Hammer, Sylvia Michel, Michel Ramonet, Martina Schmidt, Armin Jordan, Heiko Moossen, Michael Rothe, Ralph Keeling, and Eric J. Morgan
Atmos. Meas. Tech., 16, 5909–5935, https://doi.org/10.5194/amt-16-5909-2023, https://doi.org/10.5194/amt-16-5909-2023, 2023
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Network compatibility is important for inferring greenhouse gas fluxes at global or regional scales. This study is the first assessment of the measurement agreement among seven individual programs within the World Meteorological Organization community. It compares co-located flask air measurements at the Alert Observatory in Canada over a 17-year period. The results provide stronger confidence in the uncertainty estimation while using those datasets in various data interpretation applications.
Robbert P. J. Moonen, Getachew A. Adnew, Oscar K. Hartogensis, Jordi Vilà-Guerau de Arellano, David J. Bonell Fontas, and Thomas Röckmann
Atmos. Meas. Tech., 16, 5787–5810, https://doi.org/10.5194/amt-16-5787-2023, https://doi.org/10.5194/amt-16-5787-2023, 2023
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Isotope fluxes allow for net ecosystem gas exchange fluxes to be partitioned into sub-components like plant assimilation, respiration and transpiration, which can help us better understand the environmental drivers of each partial flux. We share the results of a field campaign isotope fluxes were derived using a combination of laser spectroscopy and eddy covariance. We found lag times and high frequency signal loss in the isotope fluxes we derived and present methods to correct for both.
Leonard Kirago, Örjan Gustafsson, Samuel Mwaniki Gaita, Sophie L. Haslett, Michael J. Gatari, Maria Elena Popa, Thomas Röckmann, Christoph Zellweger, Martin Steinbacher, Jörg Klausen, Christian Félix, David Njiru, and August Andersson
Atmos. Chem. Phys., 23, 14349–14357, https://doi.org/10.5194/acp-23-14349-2023, https://doi.org/10.5194/acp-23-14349-2023, 2023
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This study provides ground-observational evidence that supports earlier suggestions that savanna fires are the main emitters and modulators of carbon monoxide gas in Africa. Using isotope-based techniques, the study has shown that about two-thirds of this gas is emitted from savanna fires, while for urban areas, in this case Nairobi, primary sources approach 100 %. The latter has implications for air quality policy, suggesting primary emissions such as traffic should be targeted.
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.
Tim René de Groot, Anne Margriet Mol, Katherine Mesdag, Pierre Ramond, Rachel Ndhlovu, Julia Catherine Engelmann, Thomas Röckmann, and Helge Niemann
Biogeosciences, 20, 3857–3872, https://doi.org/10.5194/bg-20-3857-2023, https://doi.org/10.5194/bg-20-3857-2023, 2023
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This study investigates methane dynamics in the Wadden Sea. Our measurements revealed distinct variations triggered by seasonality and tidal forcing. The methane budget was higher in warmer seasons but surprisingly high in colder seasons. Methane dynamics were amplified during low tides, flushing the majority of methane into the North Sea or releasing it to the atmosphere. Methanotrophic activity was also elevated during low tide but mitigated only a small fraction of the methane efflux.
Foteini Stavropoulou, Katarina Vinković, Bert Kers, Marcel de Vries, Steven van Heuven, Piotr Korbeń, Martina Schmidt, Julia Wietzel, Pawel Jagoda, Jaroslav M. Necki, Jakub Bartyzel, Hossein Maazallahi, Malika Menoud, Carina van der Veen, Sylvia Walter, Béla Tuzson, Jonas Ravelid, Randulph Paulo Morales, Lukas Emmenegger, Dominik Brunner, Michael Steiner, Arjan Hensen, Ilona Velzeboer, Pim van den Bulk, Hugo Denier van der Gon, Antonio Delre, Maklawe Essonanawe Edjabou, Charlotte Scheutz, Marius Corbu, Sebastian Iancu, Denisa Moaca, Alin Scarlat, Alexandru Tudor, Ioana Vizireanu, Andreea Calcan, Magdalena Ardelean, Sorin Ghemulet, Alexandru Pana, Aurel Constantinescu, Lucian Cusa, Alexandru Nica, Calin Baciu, Cristian Pop, Andrei Radovici, Alexandru Mereuta, Horatiu Stefanie, Alexandru Dandocsi, Bas Hermans, Stefan Schwietzke, Daniel Zavala-Araiza, Huilin Chen, and Thomas Röckmann
Atmos. Chem. Phys., 23, 10399–10412, https://doi.org/10.5194/acp-23-10399-2023, https://doi.org/10.5194/acp-23-10399-2023, 2023
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In this study, we quantify CH4 emissions from onshore oil production sites in Romania at source and facility level using a combination of ground- and drone-based measurement techniques. We show that the total CH4 emissions in our studied areas are much higher than the emissions reported to UNFCCC, and up to three-quarters of the detected emissions are related to operational venting. Our results suggest that oil and gas production infrastructure in Romania holds a massive mitigation potential.
Sara M. Defratyka, James L. France, Rebecca E. Fisher, Dave Lowry, Julianne M. Fernandez, Semra Bakkaloglu, Camille Yver-Kwok, Jean-Daniel Paris, Philippe Bousquet, Tim Arnold, Chris Rennick, Jon Helmore, Nigel Yarrow, and Euan G. Nisbet
EGUsphere, https://doi.org/10.5194/egusphere-2023-1490, https://doi.org/10.5194/egusphere-2023-1490, 2023
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We are focused on verification of δ13CH4 measurements in near-source conditions and we have provided an insight into the impact of chosen calculation methods for determined isotopic signatures. Our study offers a step forward for establishing an unified, robust, and reliable analytical technique to determine δ13CH4 of methane sources. Our recommended analytical approach reduces biases and uncertainties coming from measurement conditions, data clustering and various available fitting methods.
Andreas Forstmaier, Jia Chen, Florian Dietrich, Juan Bettinelli, Hossein Maazallahi, Carsten Schneider, Dominik Winkler, Xinxu Zhao, Taylor Jones, Carina van der Veen, Norman Wildmann, Moritz Makowski, Aydin Uzun, Friedrich Klappenbach, Hugo Denier van der Gon, Stefan Schwietzke, and Thomas Röckmann
Atmos. Chem. Phys., 23, 6897–6922, https://doi.org/10.5194/acp-23-6897-2023, https://doi.org/10.5194/acp-23-6897-2023, 2023
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Large cities emit greenhouse gases which contribute to global warming. In this study, we measured the release of one important green house gas, methane, in Hamburg. Multiple sources that contribute to methane emissions were located and quantified. Methane sources were found to be mainly caused by human activity (e.g., by release from oil and gas refineries). Moreover, potential natural sources have been located, such as the Elbe River and lakes.
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.
Truls Andersen, Zhao Zhao, Marcel de Vries, Jaroslaw Necki, Justyna Swolkien, Malika Menoud, Thomas Röckmann, Anke Roiger, Andreas Fix, Wouter Peters, and Huilin Chen
Atmos. Chem. Phys., 23, 5191–5216, https://doi.org/10.5194/acp-23-5191-2023, https://doi.org/10.5194/acp-23-5191-2023, 2023
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The Upper Silesian Coal Basin, Poland, is one of the hot spots of methane emissions in Europe. Using an uncrewed aerial vehicle (UAV), we performed atmospheric measurements of methane concentrations downwind of five ventilation shafts in this region and determined the emission rates from the individual shafts. We found a strong correlation between quantified shaft-averaged emission rates and hourly inventory data, which also allows us to estimate the methane emissions from the entire region.
Bryce F. J. Kelly, Xinyi Lu, Stephen J. Harris, Bruno G. Neininger, Jorg M. Hacker, Stefan Schwietzke, Rebecca E. Fisher, James L. France, Euan G. Nisbet, David Lowry, Carina van der Veen, Malika Menoud, and Thomas Röckmann
Atmos. Chem. Phys., 22, 15527–15558, https://doi.org/10.5194/acp-22-15527-2022, https://doi.org/10.5194/acp-22-15527-2022, 2022
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This study explores using the composition of methane of in-flight atmospheric air samples for greenhouse gas inventory verification. The air samples were collected above one of the largest coal seam gas production regions in the world. Adjacent to these gas fields are coal mines, Australia's largest cattle feedlot, and over 1 million grazing cattle. The results are also used to identify methane mitigation opportunities.
Sourish Basu, Xin Lan, Edward Dlugokencky, Sylvia Michel, Stefan Schwietzke, John B. Miller, Lori Bruhwiler, Youmi Oh, Pieter P. Tans, Francesco Apadula, Luciana V. Gatti, Armin Jordan, Jaroslaw Necki, Motoki Sasakawa, Shinji Morimoto, Tatiana Di Iorio, Haeyoung Lee, Jgor Arduini, and Giovanni Manca
Atmos. Chem. Phys., 22, 15351–15377, https://doi.org/10.5194/acp-22-15351-2022, https://doi.org/10.5194/acp-22-15351-2022, 2022
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Atmospheric methane (CH4) has been growing steadily since 2007 for reasons that are not well understood. Here we determine sources of methane using a technique informed by atmospheric measurements of CH4 and its isotopologue 13CH4. Measurements of 13CH4 provide for better separation of microbial, fossil, and fire sources of methane than CH4 measurements alone. Compared to previous assessments such as the Global Carbon Project, we find a larger microbial contribution to the post-2007 increase.
Malika Menoud, Carina van der Veen, Dave Lowry, Julianne M. Fernandez, Semra Bakkaloglu, James L. France, Rebecca E. Fisher, Hossein Maazallahi, Mila Stanisavljević, Jarosław Nęcki, Katarina Vinkovic, Patryk Łakomiec, Janne Rinne, Piotr Korbeń, Martina Schmidt, Sara Defratyka, Camille Yver-Kwok, Truls Andersen, Huilin Chen, and Thomas Röckmann
Earth Syst. Sci. Data, 14, 4365–4386, https://doi.org/10.5194/essd-14-4365-2022, https://doi.org/10.5194/essd-14-4365-2022, 2022
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Emission sources of methane (CH4) can be distinguished with measurements of CH4 stable isotopes. We present new measurements of isotope signatures of various CH4 sources in Europe, mainly anthropogenic, sampled from 2017 to 2020. The present database also contains the most recent update of the global signature dataset from the literature. The dataset improves CH4 source attribution and the understanding of the global CH4 budget.
Qiansi Tu, Matthias Schneider, Frank Hase, Farahnaz Khosrawi, Benjamin Ertl, Jaroslaw Necki, Darko Dubravica, Christopher J. Diekmann, Thomas Blumenstock, and Dianjun Fang
Atmos. Chem. Phys., 22, 9747–9765, https://doi.org/10.5194/acp-22-9747-2022, https://doi.org/10.5194/acp-22-9747-2022, 2022
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Three-year satellite observations and high-resolution model forecast of XCH4 are used to derive CH4 emissions in the USCB region, Poland – a region of intense coal mining activities. The wind-assigned anomalies for two opposite wind directions are calculated and the estimated emission rates are very close to the inventories and in reasonable agreement with the previous studies. Our method is quite robust and can serve as a simple method to estimate CH4 or CO2 emissions for other regions.
Andreas Luther, Julian Kostinek, Ralph Kleinschek, Sara Defratyka, Mila Stanisavljević, Andreas Forstmaier, Alexandru Dandocsi, Leon Scheidweiler, Darko Dubravica, Norman Wildmann, Frank Hase, Matthias M. Frey, Jia Chen, Florian Dietrich, Jarosław Nȩcki, Justyna Swolkień, Christoph Knote, Sanam N. Vardag, Anke Roiger, and André Butz
Atmos. Chem. Phys., 22, 5859–5876, https://doi.org/10.5194/acp-22-5859-2022, https://doi.org/10.5194/acp-22-5859-2022, 2022
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Coal mining is an extensive source of anthropogenic methane emissions. In order to reduce and mitigate methane emissions, it is important to know how much and where the methane is emitted. We estimated coal mining methane emissions in Poland based on atmospheric methane measurements and particle dispersion modeling. In general, our emission estimates suggest higher emissions than expected by previous annual emission reports.
Alexandru Mereuţă, Nicolae Ajtai, Andrei T. Radovici, Nikolaos Papagiannopoulos, Lucia T. Deaconu, Camelia S. Botezan, Horaţiu I. Ştefănie, Doina Nicolae, and Alexandru Ozunu
Atmos. Chem. Phys., 22, 5071–5098, https://doi.org/10.5194/acp-22-5071-2022, https://doi.org/10.5194/acp-22-5071-2022, 2022
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In this study we analysed oil smoke plumes from 30 major industrial events within a 12-year timeframe. To our knowledge, this is the first study of its kind that uses a synergetic approach based on satellite remote sensing techniques. Satellite data offer access to these events, which are mainly located in war-prone or hazardous areas. Our study highlights the need for improved aerosol models and algorithms for these types of aerosols with implications on air quality and climate change.
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.
Stephen M. Platt, Øystein Hov, Torunn Berg, Knut Breivik, Sabine Eckhardt, Konstantinos Eleftheriadis, Nikolaos Evangeliou, Markus Fiebig, Rebecca Fisher, Georg Hansen, Hans-Christen Hansson, Jost Heintzenberg, Ove Hermansen, Dominic Heslin-Rees, Kim Holmén, Stephen Hudson, Roland Kallenborn, Radovan Krejci, Terje Krognes, Steinar Larssen, David Lowry, Cathrine Lund Myhre, Chris Lunder, Euan Nisbet, Pernilla B. Nizzetto, Ki-Tae Park, Christina A. Pedersen, Katrine Aspmo Pfaffhuber, Thomas Röckmann, Norbert Schmidbauer, Sverre Solberg, Andreas Stohl, Johan Ström, Tove Svendby, Peter Tunved, Kjersti Tørnkvist, Carina van der Veen, Stergios Vratolis, Young Jun Yoon, Karl Espen Yttri, Paul Zieger, Wenche Aas, and Kjetil Tørseth
Atmos. Chem. Phys., 22, 3321–3369, https://doi.org/10.5194/acp-22-3321-2022, https://doi.org/10.5194/acp-22-3321-2022, 2022
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Here we detail the history of the Zeppelin Observatory, a unique global background site and one of only a few in the high Arctic. We present long-term time series of up to 30 years of atmospheric components and atmospheric transport phenomena. Many of these time series are important to our understanding of Arctic and global atmospheric composition change. Finally, we discuss the future of the Zeppelin Observatory and emerging areas of future research on the Arctic atmosphere.
Roland Vernooij, Ulrike Dusek, Maria Elena Popa, Peng Yao, Anupam Shaikat, Chenxi Qiu, Patrik Winiger, Carina van der Veen, Thomas Callum Eames, Natasha Ribeiro, and Guido R. van der Werf
Atmos. Chem. Phys., 22, 2871–2890, https://doi.org/10.5194/acp-22-2871-2022, https://doi.org/10.5194/acp-22-2871-2022, 2022
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Landscape fires are a major source of greenhouse gases and aerosols, particularly in sub-tropical savannas. Stable carbon isotopes in emissions can be used to trace the contribution of C3 plants (e.g. trees or shrubs) and C4 plants (e.g. savanna grasses) to greenhouse gases and aerosols if the process is well understood. This helps us to link individual vegetation types to emissions, identify biomass burning emissions in the atmosphere, and improve the reconstruction of historic fire regimes.
Sophie F. Warken, Therese Weißbach, Tobias Kluge, Hubert Vonhof, Denis Scholz, Rolf Vieten, Martina Schmidt, Amos Winter, and Norbert Frank
Clim. Past, 18, 167–181, https://doi.org/10.5194/cp-18-167-2022, https://doi.org/10.5194/cp-18-167-2022, 2022
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The analysis of fluid inclusions from a Puerto Rican speleothem provides quantitative information about past rainfall conditions and temperatures during the Last Glacial Period, when the climate was extremely variable. Our data show that the region experienced a climate that was generally colder and drier. However, we also reconstruct intervals when temperatures reached nearly modern values, and convective activity was comparable to or only slightly weaker than the present day.
Juhi Nagori, Narcisa Nechita-Bândă, Sebastian Oscar Danielache, Masumi Shinkai, Thomas Röckmann, and Maarten Krol
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2022-68, https://doi.org/10.5194/acp-2022-68, 2022
Publication in ACP not foreseen
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The sulfur isotopes (32S and 34S) were studied to understand the sources, sinks and processes of carbonyl sulphide (COS) in the atmosphere. COS is an important source of sulfur aerosol in the stratosphere (SSA). Few measurements of COS and SSA exist, but with our 1D model, we were able to match them and show the importance of COS to sulfate formation. Moreover, we are able to highlight some important processes for the COS budget and where measurements may fill a gap in current knowledge.
Sven Krautwurst, Konstantin Gerilowski, Jakob Borchardt, Norman Wildmann, Michał Gałkowski, Justyna Swolkień, Julia Marshall, Alina Fiehn, Anke Roiger, Thomas Ruhtz, Christoph Gerbig, Jaroslaw Necki, John P. Burrows, Andreas Fix, and Heinrich Bovensmann
Atmos. Chem. Phys., 21, 17345–17371, https://doi.org/10.5194/acp-21-17345-2021, https://doi.org/10.5194/acp-21-17345-2021, 2021
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Quantification of anthropogenic CH4 emissions remains challenging, but it is essential for near-term climate mitigation strategies. We use airborne remote sensing observations to assess bottom-up estimates of coal mining emissions from one of Europe's largest CH4 emission hot spots located in Poland. The analysis reveals that emissions from small groups of shafts can be disentangled, but caution is advised when comparing observations to commonly reported annual emissions.
Anna K. Tobler, Alicja Skiba, Francesco Canonaco, Griša Močnik, Pragati Rai, Gang Chen, Jakub Bartyzel, Miroslaw Zimnoch, Katarzyna Styszko, Jaroslaw Nęcki, Markus Furger, Kazimierz Różański, Urs Baltensperger, Jay G. Slowik, and Andre S. H. Prevot
Atmos. Chem. Phys., 21, 14893–14906, https://doi.org/10.5194/acp-21-14893-2021, https://doi.org/10.5194/acp-21-14893-2021, 2021
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Kraków is among the cities with the highest particulate matter levels within Europe. We conducted long-term and highly time-resolved measurements of the chemical composition of submicron particlulate matter (PM1). Combined with advanced source apportionment techniques, which allow for time-dependent factor profiles, our results elucidate that traffic and residential heating (biomass burning and coal combustion) as well as oxygenated organic aerosol are the key PM sources in Kraków.
Malika Menoud, Carina van der Veen, Jaroslaw Necki, Jakub Bartyzel, Barbara Szénási, Mila Stanisavljević, Isabelle Pison, Philippe Bousquet, and Thomas Röckmann
Atmos. Chem. Phys., 21, 13167–13185, https://doi.org/10.5194/acp-21-13167-2021, https://doi.org/10.5194/acp-21-13167-2021, 2021
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Using measurements of methane isotopes in ambient air and a 3D atmospheric transport model, in Krakow, Poland, we mainly detected fossil-fuel-related sources, coming from coal mining in Silesia and from the use of natural gas in the city. Emission inventories report large emissions from coal mine activity in Silesia, which is in agreement with our measurements. However, methane sources in the urban area of Krakow related to the use of fossil fuels might be underestimated in the inventories.
Sara M. Defratyka, Jean-Daniel Paris, Camille Yver-Kwok, Daniel Loeb, James France, Jon Helmore, Nigel Yarrow, Valérie Gros, and Philippe Bousquet
Atmos. Meas. Tech., 14, 5049–5069, https://doi.org/10.5194/amt-14-5049-2021, https://doi.org/10.5194/amt-14-5049-2021, 2021
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We consider the possibility of using the CRDS Picarro G2201-i instrument, originally designed for isotopic CH4 and CO2, for measurements of ethane : methane in near-source conditions. The work involved laboratory tests, a controlled release experiment and mobile measurements. We show the potential of determining ethane : methane with 50 ppb ethane uncertainty. The instrument can correctly estimate the ratio in CH4 enhancements of 1 ppm and more, as can be found at strongly emitting sites.
Cited articles
Baciu, C., Etiope, G., Cuna, S., and Spulber, L.: Methane seepage in an urban development area (Bacau, Romania): origin, extent, and hazard, Geofluids, 8, 311–320, https://doi.org/10.1111/J.1468-8123.2008.00228.X, 2008.
Baciu, C., Ionescu, A., and Etiope, G.: Hydrocarbon seeps in Romania: Gas origin and release to the atmosphere, Marine and Petroleum Geology, 89, 130–143, https://doi.org/10.1016/j.marpetgeo.2017.06.015, 2018.
Boggs, P. T., Spiegelman, C. H., Donaldson, J. R., and Schnabel, R. B.: A computational examination of orthogonal distance regression, Journal of Econometrics, 38, 169–201, https://doi.org/10.1016/0304-4076(88)90032-2, 1988.
Brass, M. and Röckmann, T.: Continuous-flow isotope ratio mass spectrometry method for carbon and hydrogen isotope measurements on atmospheric methane, Atmos. Meas. Tech., 3, 1707–1721, https://doi.org/10.5194/amt-3-1707-2010, 2010.
Brenninkmeijer, C. A. M., Janssen, C., Kaiser, J., Röckmann, T., Rhee, T. S., and Assonov, S. S.: Isotope effects in the chemistry of atmospheric trace gases, Chem. Rev., 103, 5125–5162, 2003.
Defratyka, S. M., France, J. L., Fisher, R. E., Lowry, D., Fernandez, J. M., Bakkaloglu, S., Yver-Kwok, C., Paris, J.-D., Bousquet, P., Arnold, T., Rennick, C., Helmore, J., Yarrow, N., and Nisbet, E. G.: Evaluation of Data Processing Strategies for Methane Isotopic Signatures Determined During Near-Source Measurements, Tellus B: Chemical and Physical Meteorology, 77, https://doi.org/10.16993/tellusb.1878, 2025.
Delre, A., Hensen, A., Velzeboer, I., van den Bulk, P., Edjabou, M. E., and Scheutz, C.: Methane and ethane emission quantifications from onshore oil and gas sites in Romania, using a tracer gas dispersion method, Elementa: Science of the Anthropocene, 10, https://doi.org/10.1525/elementa.2021.000111, 2022.
Etiope, G.: Natural emissions of methane from geological seepage in Europe, Atmos. Environ., 43, 1430–1443, https://doi.org/10.1016/j.atmosenv.2008.03.014, 2009.
Etiope, G., Baciu, C. L., and Schoell, M.: Extreme methane deuterium, nitrogen and helium enrichment in natural gas from the Homorod seep (Romania), Chem. Geol., 280, 89–96, https://doi.org/10.1016/j.chemgeo.2010.10.019, 2011.
Fernandez, J. M., Maazallahi, H., France, J. L., Menoud, M., Corbu, M., Ardelean, M., Calcan, A., Townsend-Small, A., van der Veen, C., Fisher, R. E., Lowry, D., Nisbet, E. G., and Röckmann, T.: Street-level methane emissions of Bucharest, Romania and the dominance of urban wastewater, Atmospheric Environment: X, 13, 100153, https://doi.org/10.1016/j.aeaoa.2022.100153, 2022.
Fiehn, A., Eckl, M., Kostinek, J., Gałkowski, M., Gerbig, C., Rothe, M., Röckmann, T., Menoud, M., Maazallahi, H., Schmidt, M., Korbeń, P., Neçki, J., Stanisavljević, M., Swolkień, J., Fix, A., and Roiger, A.: Source apportionment of methane emissions from the Upper Silesian Coal Basin using isotopic signatures, Atmos. Chem. Phys., 23, 15749–15765, https://doi.org/10.5194/acp-23-15749-2023, 2023.
Höglund-Isaksson, L., Gómez-Sanabria, A., Klimont, Z., Rafaj, P., and Schöpp, W.: Technical potentials and costs for reducing global anthropogenic methane emissions in the 2050 timeframe – results from the GAINS model, Environmental Research Communications, 2, 025004, https://doi.org/10.1088/2515-7620/ab7457, 2020.
Keeling, C. D.: The concentration and isotopic abundances of carbon dioxide in rural and marine air, +Geochim. Cosmochim. Acta, 24, 277–298, https://doi.org/10.1016/0016-7037(61)90023-0, 1961.
Korbeń, P., Jagoda, P., Maazallahi, H., Kammerer, J., Nęcki, J. M., Wietzel, J. B., Bartyzel, J., Radovici, A., Zavala-Araiza, D., Röckmann, T., and Schmidt, M.: Quantification of methane emission rate from oil and gas wells in Romania using ground-based measurement techniques, Elementa: Science of the Anthropocene, 10, https://doi.org/10.1525/elementa.2022.00070, 2022.
Krézsek, C.: Petroleum Systems of Romania, Search and Discovery European Region Newsletter, Article #10349, AAPG, 6, 5–7, 2011.
Krézsek, C. and Filipescu, S.: Middle to late Miocene sequence stratigraphy of the Transylvanian Basin (Romania), Tectonophysics, 410, 437–463, https://doi.org/10.1016/j.tecto.2005.02.018, 2005.
Krézsek, C., Filipescu, S., Silye, L., Maţenco, L., and Doust, H.: Miocene facies associations and sedimentary evolution of the Southern Transylvanian Basin (Romania): Implications for hydrocarbon exploration, Marine and Petroleum Geology, 27, 191–214, https://doi.org/10.1016/j.marpetgeo.2009.07.009, 2010.
Kuhlmann, G., Stavropoulou, F., Schwietzke, S., Zavala-Araiza, D., Thorpe, A., Hueni, A., Emmenegger, L., Calcan, A., Röckmann, T., and Brunner, D.: Evidence of successful methane mitigation in one of Europe's most important oil production region, EGUsphere [preprint], https://doi.org/10.5194/egusphere-2024-3494, 2024.
Lu, X., Harris, S. J., Fisher, R. E., France, J. L., Nisbet, E. G., Lowry, D., Röckmann, T., van der Veen, C., Menoud, M., Schwietzke, S., and Kelly, B. F. J.: Isotopic Signatures of Major Methane Sources in the Coal Seam Gas Fields and Adjacent Agricultural Districts, Queensland, Australia, Atmos. Chem. Phys, 2021, 1–36, https://doi.org/10.5194/acp-2021-76, 2021.
Maazallahi, H., Fernandez, J. M., Menoud, M., Zavala-Araiza, D., Weller, Z. D., Schwietzke, S., von Fischer, J. C., Denier van der Gon, H., and Röckmann, T.: Methane mapping, emission quantification, and attribution in two European cities: Utrecht (NL) and Hamburg (DE), Atmos. Chem. Phys., 20, 14717–14740, https://doi.org/10.5194/acp-20-14717-2020, 2020.
Maazallahi, H., Stavropoulou, F., Sutanto, S. J., Steiner, M., Brunner, D., Mertens, M., Jöckel, P., Visschedijk, A., Denier van der Gon, H., Dellaert, S., Velandia Salinas, N., Schwietzke, S., Zavala-Araiza, D., Ghemulet, S., Pana, A., Ardelean, M., Corbu, M., Calcan, A., Conley, S. A., Smith, M. L., and Röckmann, T.: Airborne in situ quantification of methane emissions from oil and gas production in Romania, Atmos. Chem. Phys., 25, 1497–1511, https://doi.org/10.5194/acp-25-1497-2025, 2025.
Menoud, M., van der Veen, C., Scheeren, B., Chen, H. L., Szenasi, B., Morales, R. P., Pison, I., Bousquet, P., Brunner, D., and Röckmann, T.: Characterisation of methane sources in Lutjewad, The Netherlands, using quasi-continuous isotopic composition measurements, Tellus B: Chemical and Physical Meteorology, 72, 1–19, https://doi.org/10.1080/16000889.2020.1823733, 2020.
Menoud, M., van der Veen, C., Necki, J., Bartyzel, J., Szénási, B., Stanisavljević, M., Pison, I., Bousquet, P., and Röckmann, T.: Methane (CH4) sources in Krakow, Poland: insights from isotope analysis, Atmos. Chem. Phys., 21, 13167–13185, https://doi.org/10.5194/acp-21-13167-2021, 2021.
Menoud, M., van der Veen, C., Lowry, D., Fernandez, J. M., Bakkaloglu, S., France, J. L., Fisher, R. E., Maazallahi, H., Stanisavljević, M., Nęcki, J., Vinkovic, K., Łakomiec, P., Rinne, J., Korbeń, P., Schmidt, M., Defratyka, S., Yver-Kwok, C., Andersen, T., Chen, H., and Röckmann, T.: New contributions of measurements in Europe to the global inventory of the stable isotopic composition of methane, Earth Syst. Sci. Data, 14, 4365–4386, https://doi.org/10.5194/essd-14-4365-2022, 2022a.
Menoud, M., van der Veen, C., Maazallahi, H., Hensen, A., Velzeboer, I., van den Bulk, P., Delre, A., Korben, P., Schwietzke, S., Ardelean, M., Calcan, A., Etiope, G., Baciu, C., Scheutz, C., Schmidt, M., and Röckmann, T.: CH4 isotopic signatures of emissions from oil and gas extraction sites in Romania, Elementa: Science of the Anthropocene, 10, https://doi.org/10.1525/elementa.2021.00092, 2022b.
Milkov, A. V. and Etiope, G.: Revised genetic diagrams for natural gases based on a global dataset of > 20,000 samples, Org. Geochem., 125, 109–120, https://doi.org/10.1016/j.orggeochem.2018.09.002, 2018.
Miller, J. B. and Tans, P. P.: Calculating isotopic fractionation from atmospheric measurements at various scales, Tellus B: Chemical and Physical Meteorology, 55, 207–214, 2003.
Nisbet, E. G., Manning, M. R., Dlugokencky, E. J., Fisher, R. E., Lowry, D., Michel, S. E., Myhre, C. L., Platt, M., Allen, G., Bousquet, P., Brownlow, R., Cain, M., France, J. L., Hermansen, O., Hossaini, R., Jones, A. E., Levin, I., Manning, A. C., Myhre, G., Pyle, J. A., Vaughn, B. H., Warwick, N. J., and White, J. W. C.: Very Strong Atmospheric Methane Growth in the 4 Years 2014-2017: Implications for the Paris Agreement, Global Biogeochem. Cycles, 33, 318–342, https://doi.org/10.1029/2018gb006009, 2019.
Nisbet, E. G., Fisher, R. E., Lowry, D., France, J. L., Allen, G., Bakkaloglu, S., Broderick, T. J., Cain, M., Coleman, M., Fernandez, J., Forster, G., Griffiths, P. T., Iverach, C. P., Kelly, B. F. J., Manning, M. R., Nisbet-Jones, P. B. R., Pyle, J. A., Townsend-Small, A., al-Shalaan, A., Warwick, N., and Zazzeri, G.: Methane Mitigation: Methods to Reduce Emissions, on the Path to the Paris Agreement, Reviews of Geophysics, 58, e2019RG000675., https://doi.org/10.1029/2019RG000675, 2020.
Ocko, I. B., Sun, T., Shindell, D., Oppenheimer, M., Hristov, A. N., Pacala, S. W., Mauzerall, D. L., Xu, Y., and Hamburg, S. P.: Acting rapidly to deploy readily available methane mitigation measures by sector can immediately slow global warming, Environmental Research Letters, 16, 054042, https://doi.org/10.1088/1748-9326/abf9c8, 2021.
Ojeda, L., Etiope, G., Jiménez-Gavilán, P., Martonos, I. M., Röckmann, T., Popa, M. E., Sivan, M., Castro-Gámez, A. F., Benavente, J., and Vadillo, I.: Combining methane clumped and bulk isotopes, temporal variations in molecular and isotopic composition, and hydrochemical and geological proxies to understand methane's origin in the Ronda peridotite massifs (Spain), Chem. Geol., 642, https://doi.org/10.1016/j.chemgeo.2023.121799, 2023.
Paraschiv, D.: Romanian oil and gas fields, Tech. Ec. Stud. A, 13, 1–382, 1979.
Pawlewicz, M.: Transylvanian Composite Total Petroleum System of the Transylvanian Basin Province, Romania, Eastern Europe, US Geological Survey Bulletin 2204–E, US Geological Survey, p. 10, http://pubs.usgs.gov/bul/2204/e (last access: 13 January 2026), 2005.
Popescu, B. M.: Romania's petroleum systems and their remaining potential, Petroleum Geoscience, 1, 337–350, https://doi.org/10.1144/petgeo.1.4.337, 1995.
Quay, P., Stutsman, J., Wilbur, D., Snover, A., Dlugokencky, E., and Brown, T.: The isotopic composition of atmospheric methane, Global Biogeochem. Cy., 13, 445–461, 1999.
Röckmann, T., Brass, M., Borchers, R., and Engel, A.: The isotopic composition of methane in the stratosphere: high-altitude balloon sample measurements, Atmos. Chem. Phys., 11, 13287–13304, https://doi.org/10.5194/acp-11-13287-2011, 2011.
Röckmann, T., Eyer, S., van der Veen, C., Popa, M. E., Tuzson, B., Monteil, G., Houweling, S., Harris, E., Brunner, D., Fischer, H., Zazzeri, G., Lowry, D., Nisbet, E. G., Brand, W. A., Necki, J. M., Emmenegger, L., and Mohn, J.: In situ observations of the isotopic composition of methane at the Cabauw tall tower site, Atmos. Chem. Phys., 16, 10469–10487, https://doi.org/10.5194/acp-16-10469-2016, 2016.
Röckmann, T., Menoud, M., van Es, J., van der Veen, C., Maazallahi, H., Jagoda, P., Nęcki, J., Bartyzel, J., Korben, P., Defratyka, S., Schmidt, M., Corbu, M., Iancu, S., Calcan, A., Ardelean, M., Ghemulet, S., Pop, C., Radovici, A., Mereuta, A., Stefanie, H., and Baciu, C.: Isotopic composition of methane emitted from gas production sites in Transylvania, ICOS [data set], https://doi.org/10.18160/4SJW-ST8W, 2025.
Schwietzke, S., Sherwood, O. A., Ruhwiler, L. M. P. B., Miller, J. B., Etiope, G., Dlugokencky, E. J., Michel, S. E., Arling, V. A., Vaughn, B. H., White, J. W. C., and Tans, P. P.: Upward revision of global fossil fuel methane emissions based on isotope database, Nature, 538, 88–91, https://doi.org/10.1038/nature19797, 2016.
Sherwood, O. A., Schwietzke, S., Arling, V. A., and Etiope, G.: Global Inventory of Gas Geochemistry Data from Fossil Fuel, Microbial and Burning Sources, version 2017, Earth Syst. Sci. Data, 9, 639–656, https://doi.org/10.5194/essd-9-639-2017, 2017.
Sherwood Lollar, B., Lacrampe-Couloume, G., Slater, G. F., Ward, J., Moser, D. P., Gihring, T. M., Lin, L. H., and Onstott, T. C.: Unravelling abiogenic and biogenic sources of methane in the Earth's deep subsurface, Chem. Geol., 226, 328–339, https://doi.org/10.1016/j.chemgeo.2005.09.027, 2006.
Stavropoulou, F., Vinković, K., Kers, B., de Vries, M., van Heuven, S., Korbeń, P., Schmidt, M., Wietzel, J., Jagoda, P., Necki, J. M., Bartyzel, J., Maazallahi, H., Menoud, M., van der Veen, C., Walter, S., Tuzson, B., Ravelid, J., Morales, R. P., Emmenegger, L., Brunner, D., Steiner, M., Hensen, A., Velzeboer, I., van den Bulk, P., Denier van der Gon, H., Delre, A., Edjabou, M. E., Scheutz, C., Corbu, M., Iancu, S., Moaca, D., Scarlat, A., Tudor, A., Vizireanu, I., Calcan, A., Ardelean, M., Ghemulet, S., Pana, A., Constantinescu, A., Cusa, L., Nica, A., Baciu, C., Pop, C., Radovici, A., Mereuta, A., Stefanie, H., Dandocsi, A., Hermans, B., Schwietzke, S., Zavala-Araiza, D., Chen, H., and Röckmann, T.: High potential for CH4 emission mitigation from oil infrastructure in one of EU's major production regions, Atmos. Chem. Phys., 23, 10399–10412, https://doi.org/10.5194/acp-23-10399-2023, 2023.
Tiliţă, M., Matenco, L., Dinu, C., Ionescu, L., and Cloetingh, S.: Understanding the kinematic evolution and genesis of a back-arc continental “sag” basin: The Neogene evolution of the Transylvanian Basin, Tectonophysics, 602, 237–258, https://doi.org/10.1016/j.tecto.2012.12.029, 2013.
Umezawa, T., Brenninkmeijer, C. A. M., Röckmann, T., van der Veen, C., Tyler, S. C., Fujita, R., Morimoto, S., Aoki, S., Sowers, T., Schmitt, J., Bock, M., Beck, J., Fischer, H., Michel, S. E., Vaughn, B. H., Miller, J. B., White, J. W. C., Brailsford, G., Schaefer, H., Sperlich, P., Brand, W. A., Rothe, M., Blunier, T., Lowry, D., Fisher, R. E., Nisbet, E. G., Rice, A. L., Bergamaschi, P., Veidt, C., and Levin, I.: Interlaboratory comparison of δ13C and δD measurements of atmospheric CH4 for combined use of data sets from different laboratories, Atmos. Meas. Tech., 11, 1207–1231, https://doi.org/10.5194/amt-11-1207-2018, 2018.
United Nations Environment Programme and Climate and Clean Air Coalition: Global Methane Assessment: Benefits and Costs of Mitigating Methane Emissions, United Nations Environment Programme, Nairobi, Job No. DTI/2352/PA, ISBN 978-92-807-3854-4, 2021.
van Es, J., van der Veen, C., Baciu, C., Hmoudah, M., Menoud, M., Henne, S., and Röckmann, T.: Methane sources in Cluj-Napoca, Romania: Insights from isotopic analysis, ESS Open Archive, https://doi.org/10.22541/essoar.173272758.85099453/v1, 2024.
Whiticar, M. J.: The Biogeochemical Methane Cycle, in: Hydrocarbons, Oils and Lipids: Diversity, Origin, Chemistry and Fate, Handbook of Hydrocarbon and Lipid Microbiology, edited bu: Wilkes, H., Springer, Cham, https://doi.org/10.1007/978-3-319-90569-3_5, 2020.
Short summary
We report the isotopic composition of CH4 emitted from 48 installations in the gas production region of Transylvania, Romania which confirm the biogenic origin of the Transylvanian gas, produced by hydrogenotrophic CO2 reduction. This is similar to values reported previously from natural seeps and natural gas in a major city in the region. However, is more depleted in heavy isotopes than the oil-associated gas emitted in the Southern Romanian Plain, and gas leakages in the city of Bucharest.
We report the isotopic composition of CH4 emitted from 48 installations in the gas production...
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