Articles | Volume 17, issue 12
https://doi.org/10.5194/essd-17-6889-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/essd-17-6889-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Data description paper
| 
08 Dec 2025
Data description paper |
| 08 Dec 2025
| 08 Dec 2025
Global inventory of doubly substituted isotopologues of methane (Δ13CH3D and Δ12CH2D2)
Sara M. Defratyka
CORRESPONDING AUTHOR
School of GeoSciences, University of Edinburgh, Edinburgh, UK
National Physical Laboratory, Hampton Road, London, UK
Julianne M. Fernandez
Department of Geology, University of Maryland, College Park, Maryland, MD 20742, USA
now at: Global Monitoring Laboratory, National Oceanic and Atmospheric Administration, Boulder, CO 80305, USA
Getachew A. Adnew
Terrestrial Ecosystem Analysis Group, Institute of Geography, People and Processes, Department of Geosciences and Resource management, Science Faculty, University of Copenhagen, Øster Voldgade 10 1350 Copenhagen K, Denmark
Guannan Dong
Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA 91125, USA
Peter M. J. Douglas
Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA 91125, USA
Daniel L. Eldridge
Earth and Environmental Sciences Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
Giuseppe Etiope
Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma 2, Rome, Italy
Faculty of Environmental Science and Engineering, Babes-Bolyai University, Cluj-Napoca, Romania
Thomas Giunta
Geo-Ocean (UMR6538), University Brest, CNRS, Ifremer, Plouzané, France
Mojhgan A. Haghnegahdar
Department of Geology, University of Maryland, College Park, Maryland, MD 20742, USA
Alexander N. Hristov
Department of Animal Science, The Pennsylvania State University, Pennsylvania, PA 16803, USA
Nicole Hultquist
Department of Geology, University of Maryland, College Park, Maryland, MD 20742, USA
Iñaki Vadillo
Department of Geology, Faculty of Science, University of Malaga, Malaga, Spain
Josue Jautzy
Geological Survey of Canada – Natural Resources Canada, Ottawa, Canada
Ji-Hyun Kim
Marine Geology & Energy Division, Korea Institute of Geoscience and Mineral Resources, Daejeon, South Korea
Jabrane Labidi
Université de Paris, Institut de Physique du Globe de Paris, CNRS, 75005 Paris, France
Ellen Lalk
Department of Earth, Atmospheric, and Planetary Sciences, Massachusetts Institute of Technology, 77 Massachusetts Ave, Cambridge, MA 02139, USA
now at: U.S. Geological Survey, Woods Hole Coastal and Marine Science Center, Woods Hole, MA 02543, USA
Wil Leavitt
Department of Geology & Geophysics, University of Utah, Salt Lake City, UT 84112, USA
Department of Earth Sciences, Dartmouth College, Hanover, NH 03755, USA
Department of Chemistry, Dartmouth College, Hanover, NH 03755, USA
Jiawen Li
Department of Earth Sciences, Dartmouth College, Hanover, NH 03755, USA
Li-Hung Lin
Department of Geosciences, National Taiwan University, Taipei 106, Taiwan
Jiarui Liu
Marine Science Institute, University of California, Santa Barbara, California 93106, USA
Department of Earth, Planetary, and Space Sciences, University of California, Los Angeles, California 90095, USA
Lucía Ojeda
Department of Geology, Faculty of Science, University of Malaga, Malaga, Spain
Shuhei Ono
Department of Earth, Atmospheric, and Planetary Sciences, Massachusetts Institute of Technology, 77 Massachusetts Ave, Cambridge, MA 02139, USA
Jeemin H. Rhim
Department of Ecology, Evolution, and Marine Biology University of California, Santa Barbara, CA 93117, USA
Thomas Röckmann
Institute for Marine and Atmospheric research Utrecht (IMAU), Utrecht University, Utrecht, the Netherlands
Barbara Sherwood Lollar
Department of Earth Sciences, 22 Ursula Franklin St. University of Toronto, Toronto, ON M5S 3B1, Canada
Malavika Sivan
Institute for Marine and Atmospheric research Utrecht (IMAU), Utrecht University, Utrecht, the Netherlands
Jiayang Sun
Department of Geology, University of Maryland, College Park, Maryland, MD 20742, USA
Air Resources Laboratory, National Oceanic and Atmospheric Administration, College Park, Maryland 20740, USA
Gregory T. Ventura
Department of Geology, Saint Mary's University, Halifax, NS B3H 3C3, Canada
David T. Wang
Department of Earth, Atmospheric, and Planetary Sciences, Massachusetts Institute of Technology, 77 Massachusetts Ave, Cambridge, MA 02139, USA
now at: U.S. Department of Energy, 1000 Independence Ave SW, Washington, DC 20585, USA
Edward D. Young
Department of Earth, Planetary, and Space Sciences, University of California, Los Angeles, California 90095, USA
Naizhong Zhang
Laboratory for Air Pollution/Environmental Technology, Empa, 8600 Dübendorf, Switzerland
Tim Arnold
Department of Physical Geography and Ecosystem Science, Lund University, Lund, Sweden
School of GeoSciences, University of Edinburgh, Edinburgh, UK
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Bella J. Duncan, Robert McKay, Richard Levy, Joseph G. Prebble, Timothy Naish, Osamu Seki, Christoph Kraus, Heiko Moossen, G. Todd Ventura, Denise K. Kulhanek, and James Bendle
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We present records of the triple oxygen isotope signature (Δ(17O)) of atmospheric CO2 obtained with laser absorption spectroscopy from two mid-latitude stations. Significant interannual variability is observed in both records. A model sensitivity study suggests that stratosphere–troposphere exchange, which carries high-Δ(17O) CO2 from the stratosphere into the troposphere, causes most of the variability. This makes Δ(17O) a potential tracer for stratospheric intrusions into the troposphere.
Ana Maria Roxana Petrescu, Glen P. Peters, Richard Engelen, Sander Houweling, Dominik Brunner, Aki Tsuruta, Bradley Matthews, Prabir K. Patra, Dmitry Belikov, Rona L. Thompson, Lena Höglund-Isaksson, Wenxin Zhang, Arjo J. Segers, Giuseppe Etiope, Giancarlo Ciotoli, Philippe Peylin, Frédéric Chevallier, Tuula Aalto, Robbie M. Andrew, David Bastviken, Antoine Berchet, Grégoire Broquet, Giulia Conchedda, Stijn N. C. Dellaert, Hugo Denier van der Gon, Johannes Gütschow, Jean-Matthieu Haussaire, Ronny Lauerwald, Tiina Markkanen, Jacob C. A. van Peet, Isabelle Pison, Pierre Regnier, Espen Solum, Marko Scholze, Maria Tenkanen, Francesco N. Tubiello, Guido R. van der Werf, and John R. Worden
Earth Syst. Sci. Data, 16, 4325–4350, https://doi.org/10.5194/essd-16-4325-2024, https://doi.org/10.5194/essd-16-4325-2024, 2024
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This study provides an overview of data availability from observation- and inventory-based CH4 emission estimates. It systematically compares them and provides recommendations for robust comparisons, aiming to steadily engage more parties in using observational methods to complement their UNFCCC submissions. Anticipating improvements in atmospheric modelling and observations, future developments need to resolve knowledge gaps in both approaches and to better quantify remaining uncertainty.
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.
Hannah Chawner, Eric Saboya, Karina E. Adcock, Tim Arnold, Yuri Artioli, Caroline Dylag, Grant L. Forster, Anita Ganesan, Heather Graven, Gennadi Lessin, Peter Levy, Ingrid T. Luijkx, Alistair Manning, Penelope A. Pickers, Chris Rennick, Christian Rödenbeck, and Matthew Rigby
Atmos. Chem. Phys., 24, 4231–4252, https://doi.org/10.5194/acp-24-4231-2024, https://doi.org/10.5194/acp-24-4231-2024, 2024
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The quantity of atmospheric potential oxygen (APO), derived from coincident measurements of carbon dioxide (CO2) and oxygen (O2), has been proposed as a tracer for fossil fuel CO2 emissions. In this model sensitivity study, we examine the use of APO for this purpose in the UK and compare our model to observations. We find that our model simulations are most sensitive to uncertainties relating to ocean fluxes and boundary conditions.
Chueh-Chen Tung, Yu-Shih Lin, Jian-Xiang Liao, Tzu-Hsuan Tu, James T. Liu, Li-Hung Lin, Pei-Ling Wang, and Chih-Lin Wei
Biogeosciences, 21, 1729–1756, https://doi.org/10.5194/bg-21-1729-2024, https://doi.org/10.5194/bg-21-1729-2024, 2024
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This study contrasts seabed food webs between a river-fed, high-energy canyon and the nearby slope. We show higher organic carbon (OC) flows through the canyon than the slope. Bacteria dominated the canyon, while seabed fauna contributed more to the slope food web. Due to frequent perturbation, the canyon had a lower faunal stock and OC recycling. Only 4 % of the seabed OC flux enters the canyon food web, suggesting a significant role of the river-fed canyon in transporting OC to the deep sea.
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.
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.
Jonathan Obrist-Farner, Andreas Eckert, Peter M. J. Douglas, Liseth Perez, Alex Correa-Metrio, Bronwen L. Konecky, Thorsten Bauersachs, Susan Zimmerman, Stephanie Scheidt, Mark Brenner, Steffen Kutterolf, Jeremy Maurer, Omar Flores, Caroline M. Burberry, Anders Noren, Amy Myrbo, Matthew Lachniet, Nigel Wattrus, Derek Gibson, and the LIBRE scientific team
Sci. Dril., 32, 85–100, https://doi.org/10.5194/sd-32-85-2023, https://doi.org/10.5194/sd-32-85-2023, 2023
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In August 2022, 65 scientists from 13 countries gathered in Antigua, Guatemala, for a workshop, co-funded by the US National Science Foundation and the International Continental Scientific Drilling Program. This workshop considered the potential of establishing a continental scientific drilling program in the Lake Izabal Basin, eastern Guatemala, with the goals of establishing a borehole observatory and investigating one of the longest continental records from the northern Neotropics.
Sebastian J. E. Krause, Jiarui Liu, David J. Yousavich, DeMarcus Robinson, David W. Hoyt, Qianhui Qin, Frank Wenzhöfer, Felix Janssen, David L. Valentine, and Tina Treude
Biogeosciences, 20, 4377–4390, https://doi.org/10.5194/bg-20-4377-2023, https://doi.org/10.5194/bg-20-4377-2023, 2023
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Methane is a potent greenhouse gas, and hence it is important to understand its sources and sinks in the environment. Here we present new data from organic-rich surface sediments below an oxygen minimum zone off the coast of California (Santa Barbara Basin) demonstrating the simultaneous microbial production and consumption of methane, which appears to be an important process preventing the build-up of methane in these sediments and the emission into the water column and atmosphere.
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.
Alice Drinkwater, Paul I. Palmer, Liang Feng, Tim Arnold, Xin Lan, Sylvia E. Michel, Robert Parker, and Hartmut Boesch
Atmos. Chem. Phys., 23, 8429–8452, https://doi.org/10.5194/acp-23-8429-2023, https://doi.org/10.5194/acp-23-8429-2023, 2023
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Changes in atmospheric methane over the last few decades are largely unexplained. Previous studies have proposed different hypotheses to explain short-term changes in atmospheric methane. We interpret observed changes in atmospheric methane and stable isotope source signatures (2004–2020). We argue that changes over this period are part of a large-scale shift from high-northern-latitude thermogenic energy emissions to tropical biogenic emissions, particularly from North Africa and South America.
Petr Brož, Dorothy Oehler, Adriano Mazzini, Ernst Hauber, Goro Komatsu, Giuseppe Etiope, and Vojtěch Cuřín
Earth Surf. Dynam., 11, 633–661, https://doi.org/10.5194/esurf-11-633-2023, https://doi.org/10.5194/esurf-11-633-2023, 2023
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The aim of this review is to summarise the current knowledge about mud-volcano-like structures on Mars, address critical aspects of the process of sedimentary volcanism, identify key open questions, and point to areas where further research is needed to understand this phenomenon and its importance in the Red Planet's geological evolution.
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.
Ana Maria Roxana Petrescu, Chunjing Qiu, Matthew J. McGrath, Philippe Peylin, Glen P. Peters, Philippe Ciais, Rona L. Thompson, Aki Tsuruta, Dominik Brunner, Matthias Kuhnert, Bradley Matthews, Paul I. Palmer, Oksana Tarasova, Pierre Regnier, Ronny Lauerwald, David Bastviken, Lena Höglund-Isaksson, Wilfried Winiwarter, Giuseppe Etiope, Tuula Aalto, Gianpaolo Balsamo, Vladislav Bastrikov, Antoine Berchet, Patrick Brockmann, Giancarlo Ciotoli, Giulia Conchedda, Monica Crippa, Frank Dentener, Christine D. Groot Zwaaftink, Diego Guizzardi, Dirk Günther, Jean-Matthieu Haussaire, Sander Houweling, Greet Janssens-Maenhout, Massaer Kouyate, Adrian Leip, Antti Leppänen, Emanuele Lugato, Manon Maisonnier, Alistair J. Manning, Tiina Markkanen, Joe McNorton, Marilena Muntean, Gabriel D. Oreggioni, Prabir K. Patra, Lucia Perugini, Isabelle Pison, Maarit T. Raivonen, Marielle Saunois, Arjo J. Segers, Pete Smith, Efisio Solazzo, Hanqin Tian, Francesco N. Tubiello, Timo Vesala, Guido R. van der Werf, Chris Wilson, and Sönke Zaehle
Earth Syst. Sci. Data, 15, 1197–1268, https://doi.org/10.5194/essd-15-1197-2023, https://doi.org/10.5194/essd-15-1197-2023, 2023
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This study updates the state-of-the-art scientific overview of CH4 and N2O emissions in the EU27 and UK in Petrescu et al. (2021a). Yearly updates are needed to improve the different respective approaches and to inform on the development of formal verification systems. It integrates the most recent emission inventories, process-based model and regional/global inversions, comparing them with UNFCCC national GHG inventories, in support to policy to facilitate real-time verification procedures.
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.
Peter Bergamaschi, Arjo Segers, Dominik Brunner, Jean-Matthieu Haussaire, Stephan Henne, Michel Ramonet, Tim Arnold, Tobias Biermann, Huilin Chen, Sebastien Conil, Marc Delmotte, Grant Forster, Arnoud Frumau, Dagmar Kubistin, Xin Lan, Markus Leuenberger, Matthias Lindauer, Morgan Lopez, Giovanni Manca, Jennifer Müller-Williams, Simon O'Doherty, Bert Scheeren, Martin Steinbacher, Pamela Trisolino, Gabriela Vítková, and Camille Yver Kwok
Atmos. Chem. Phys., 22, 13243–13268, https://doi.org/10.5194/acp-22-13243-2022, https://doi.org/10.5194/acp-22-13243-2022, 2022
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We present a novel high-resolution inverse modelling system, "FLEXVAR", and its application for the inverse modelling of European CH4 emissions in 2018. The new system combines a high spatial resolution of 7 km x 7 km with a variational data assimilation technique, which allows CH4 emissions to be optimized from individual model grid cells. The high resolution allows the observations to be better reproduced, while the derived emissions show overall good consistency with two existing models.
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.
Jeremy N. Bentley, Gregory T. Ventura, Clifford C. Walters, Stefan M. Sievert, and Jeffrey S. Seewald
Biogeosciences, 19, 4459–4477, https://doi.org/10.5194/bg-19-4459-2022, https://doi.org/10.5194/bg-19-4459-2022, 2022
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We demonstrate the TEX86 (TetraEther indeX of 86 carbon atoms) paleoclimate proxy can become heavily impacted by the ocean floor archaeal community. The impact results from source inputs, their diagenetic and catagenetic alteration, and further overprint by the additions of lipids from the ocean floor sedimentary archaeal community. We then present a method to correct the overprints by using IPLs (intact polar lipids) extracted from both water column and subsurface archaeal communities.
Christopher J. Hollis, Sebastian Naeher, Christopher D. Clowes, B. David A. Naafs, Richard D. Pancost, Kyle W. R. Taylor, Jenny Dahl, Xun Li, G. Todd Ventura, and Richard Sykes
Clim. Past, 18, 1295–1320, https://doi.org/10.5194/cp-18-1295-2022, https://doi.org/10.5194/cp-18-1295-2022, 2022
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Previous studies of Paleogene greenhouse climates identified short-lived global warming events, termed hyperthermals, that provide insights into global warming scenarios. Within the same time period, we have identified a short-lived cooling event in the late Paleocene, which we term a hypothermal, that has potential to provide novel insights into the feedback mechanisms at work in a greenhouse climate.
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.
Alice E. Ramsden, Anita L. Ganesan, Luke M. Western, Matthew Rigby, Alistair J. Manning, Amy Foulds, James L. France, Patrick Barker, Peter Levy, Daniel Say, Adam Wisher, Tim Arnold, Chris Rennick, Kieran M. Stanley, Dickon Young, and Simon O'Doherty
Atmos. Chem. Phys., 22, 3911–3929, https://doi.org/10.5194/acp-22-3911-2022, https://doi.org/10.5194/acp-22-3911-2022, 2022
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Quantifying methane emissions from different sources is a key focus of current research. We present a method for estimating sectoral methane emissions that uses ethane as a tracer for fossil fuel methane. By incorporating variable ethane : methane emission ratios into this model, we produce emissions estimates with improved uncertainty characterisation. This method will be particularly useful for studying methane emissions in areas with complex distributions of sources.
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.
Regina Gonzalez Moguel, Felix Vogel, Sébastien Ars, Hinrich Schaefer, Jocelyn C. Turnbull, and Peter M. J. Douglas
Atmos. Chem. Phys., 22, 2121–2133, https://doi.org/10.5194/acp-22-2121-2022, https://doi.org/10.5194/acp-22-2121-2022, 2022
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Evaluating methane (CH4) sources in the Athabasca oil sands region (AOSR) is crucial to effectively mitigate CH4 emissions. We tested the use of carbon isotopes to estimate source contributions from key CH4 sources in the AOSR and found that 56 ± 18 % of CH4 emissions originated from surface mining and processing facilities, 34 ± 18 % from tailings ponds, and 10 ± < 1 % from wetlands, confirming previous findings and showing that this method can be successfully used to partition CH4 sources.
Tzu-Hsuan Tu, Li-Ling Chen, Yi-Ping Chiu, Li-Hung Lin, Li-Wei Wu, Francesco Italiano, J. Bruce H. Shyu, Seyed Naser Raisossadat, and Pei-Ling Wang
Biogeosciences, 19, 831–843, https://doi.org/10.5194/bg-19-831-2022, https://doi.org/10.5194/bg-19-831-2022, 2022
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This investigation of microbial biogeography in terrestrial mud volcanoes (MVs) covers study sites over a geographic distance of up to 10 000 km across the Eurasian continent. It compares microbial community compositions' coupling with geochemical data across a 3D space. We demonstrate that stochastic processes operating at continental scales and environmental filtering at local scales drive the formation of patchy habitats and the pattern of diversification for microbes in terrestrial MVs.
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.
Mark F. Lunt, Alistair J. Manning, Grant Allen, Tim Arnold, Stéphane J.-B. Bauguitte, Hartmut Boesch, Anita L. Ganesan, Aoife Grant, Carole Helfter, Eiko Nemitz, Simon J. O'Doherty, Paul I. Palmer, Joseph R. Pitt, Chris Rennick, Daniel Say, Kieran M. Stanley, Ann R. Stavert, Dickon Young, and Matt Rigby
Atmos. Chem. Phys., 21, 16257–16276, https://doi.org/10.5194/acp-21-16257-2021, https://doi.org/10.5194/acp-21-16257-2021, 2021
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We present an evaluation of the UK's methane emissions between 2013 and 2020 using a network of tall tower measurement sites. We find emissions that are consistent in both magnitude and trend with the UK's reported emissions, with a declining trend driven by a decrease in emissions from England. The impact of various components of the modelling set-up on these findings are explored through a number of sensitivity studies.
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.
Alistair J. Manning, Alison L. Redington, Daniel Say, Simon O'Doherty, Dickon Young, Peter G. Simmonds, Martin K. Vollmer, Jens Mühle, Jgor Arduini, Gerard Spain, Adam Wisher, Michela Maione, Tanja J. Schuck, Kieran Stanley, Stefan Reimann, Andreas Engel, Paul B. Krummel, Paul J. Fraser, Christina M. Harth, Peter K. Salameh, Ray F. Weiss, Ray Gluckman, Peter N. Brown, John D. Watterson, and Tim Arnold
Atmos. Chem. Phys., 21, 12739–12755, https://doi.org/10.5194/acp-21-12739-2021, https://doi.org/10.5194/acp-21-12739-2021, 2021
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This paper estimates UK emissions of important greenhouse gases (hydrofluorocarbons (HFCs)) using high-quality atmospheric observations and atmospheric modelling. We compare these estimates with those submitted by the UK to the United Nations. We conclude that global concentrations of these gases are still increasing. Our estimates for the UK are 73 % of those reported and that the UK emissions are now falling, demonstrating an impact of UK government policy.
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.
Xinyi Lu, Stephen J. Harris, Rebecca E. Fisher, James L. France, Euan G. Nisbet, David Lowry, Thomas Röckmann, Carina van der Veen, Malika Menoud, Stefan Schwietzke, and Bryce F. J. Kelly
Atmos. Chem. Phys., 21, 10527–10555, https://doi.org/10.5194/acp-21-10527-2021, https://doi.org/10.5194/acp-21-10527-2021, 2021
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Many coal seam gas (CSG) facilities in the Surat Basin, Australia, are adjacent to other sources of methane, including agricultural, urban, and natural seeps. This makes it challenging to estimate the amount of methane being emitted into the atmosphere from CSG facilities. This research demonstrates that measurements of the carbon and hydrogen stable isotopic composition of methane can distinguish between and apportion methane emissions from CSG facilities, cattle, and many other sources.
Peter M. J. Douglas, Emerald Stratigopoulos, Sanga Park, and Dawson Phan
Biogeosciences, 18, 3505–3527, https://doi.org/10.5194/bg-18-3505-2021, https://doi.org/10.5194/bg-18-3505-2021, 2021
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Hydrogen isotopes could be a useful tool to help resolve the geographic distribution of methane emissions from freshwater environments. We analyzed an expanded global dataset of freshwater methane hydrogen isotope ratios and found significant geographic variation linked to water isotopic composition. This geographic variability could be used to resolve changing methane fluxes from freshwater environments and provide more accurate estimates of the relative balance of global methane sources.
Max Thomas, Johannes C. Laube, Jan Kaiser, Samuel Allin, Patricia Martinerie, Robert Mulvaney, Anna Ridley, Thomas Röckmann, William T. Sturges, and Emmanuel Witrant
Atmos. Chem. Phys., 21, 6857–6873, https://doi.org/10.5194/acp-21-6857-2021, https://doi.org/10.5194/acp-21-6857-2021, 2021
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CFC gases are destroying the Earth's life-protecting ozone layer. We improve understanding of CFC destruction by measuring the isotopic fingerprint of the carbon in the three most abundant CFCs. These are the first such measurements in the main region where CFCs are destroyed – the stratosphere. We reconstruct the atmospheric isotope histories of these CFCs back to the 1950s by measuring air extracted from deep snow and using a model. The model and the measurements are generally consistent.
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Short summary
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.
Measurement of methane’s doubly substituted isotopologues at natural abundances holds promise...
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