Articles | Volume 25, issue 22
https://doi.org/10.5194/acp-25-16085-2025
© 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/acp-25-16085-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Measurement report
| 
19 Nov 2025
Measurement report |
| 19 Nov 2025
| 19 Nov 2025
Measurement report: Eight years of greenhouse gas fluxes at Saclay, France, estimated with the Radon Tracer Method
Camille Yver-Kwok
CORRESPONDING AUTHOR
Laboratoire des Sciences du Climat et de l'Environnement (LSCE-IPSL), CEA-CNRS-UVSQ, Université Paris-Saclay, 91191 Gif-sur-Yvette, France
Michel Ramonet
Laboratoire des Sciences du Climat et de l'Environnement (LSCE-IPSL), CEA-CNRS-UVSQ, Université Paris-Saclay, 91191 Gif-sur-Yvette, France
Leonard Rivier
Laboratoire des Sciences du Climat et de l'Environnement (LSCE-IPSL), CEA-CNRS-UVSQ, Université Paris-Saclay, 91191 Gif-sur-Yvette, France
Jinghui Lian
Laboratoire des Sciences du Climat et de l'Environnement (LSCE-IPSL), CEA-CNRS-UVSQ, Université Paris-Saclay, 91191 Gif-sur-Yvette, France
Origins.S.A.S, Suez Group, Tour CB21, 16 Place de l'Iris, 92040 Paris La Défense, CEDEX, France
Claudia Grossi
Institut Català de Ciències del Clima (IC3), Barcelona, Spain
Roger Curcoll
Institut Català de Ciències del Clima (IC3), Barcelona, Spain
Dafina Kikaj
National Physical Laboratory, Teddington, Middlesex, United Kingdom
Edward Chung
National Physical Laboratory, Teddington, Middlesex, United Kingdom
Ute Karstens
ICOS ERIC Carbon Portal, Physical Geography and Ecosystem Science, Lund University, Sölvegatan 12, 22362 Lund, Sweden
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Laura Bouillon, Valérie Gros, Morgan Lopez, Nicolas Bonnaire, Carole Philippon, Camille Yver Kwok, Leslie David, Olivier Perrussel, Olivier Sanchez, Simone Kotthaus, Jean-Eudes Petit, Philippe Ciais, and Michel Ramonet
Earth Syst. Sci. Data Discuss., https://doi.org/10.5194/essd-2025-602, https://doi.org/10.5194/essd-2025-602, 2025
Preprint under review for ESSD
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The Saclay observatory, 20 km southwest of Paris, monitored greenhouse and reactive gases, as well as aerosols, over 10 years to assess the impact of urban emissions. By comparing downwind and background conditions, the study revealed significant reductions in pollutants linked to traffic: -35.6 % for CO, -52.3 % for NOₓ, -56.7 % for eBC, and -15 % for CO2. These trends align with emission decrease estimates from AIRPARIF inventories over the same period.
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Acetylene mole fraction measurements from the Picarro G2203 were characterised. Abnormal sensor behaviour was observed in wet conditions. A dry linear calibration was derived, although this was invalid below 1.2 ppb due to unstable measurements. The instrument was used to measure acetylene as a methane tracer at a landfill site. Fluxes were derived from 14 downwind transects using both raw and calibrated acetylene mole fraction, with raw measurements resulting in 8 % flux underestimation.
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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
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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.
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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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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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Atmos. Meas. Tech., 14, 5987–6003, https://doi.org/10.5194/amt-14-5987-2021, https://doi.org/10.5194/amt-14-5987-2021, 2021
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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.
Camille Yver-Kwok, Carole Philippon, Peter Bergamaschi, Tobias Biermann, Francescopiero Calzolari, Huilin Chen, Sebastien Conil, Paolo Cristofanelli, Marc Delmotte, Juha Hatakka, Michal Heliasz, Ove Hermansen, Kateřina Komínková, Dagmar Kubistin, Nicolas Kumps, Olivier Laurent, Tuomas Laurila, Irene Lehner, Janne Levula, Matthias Lindauer, Morgan Lopez, Ivan Mammarella, Giovanni Manca, Per Marklund, Jean-Marc Metzger, Meelis Mölder, Stephen M. Platt, Michel Ramonet, Leonard Rivier, Bert Scheeren, Mahesh Kumar Sha, Paul Smith, Martin Steinbacher, Gabriela Vítková, and Simon Wyss
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Preprint under review for ESSD
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The Saclay observatory, 20 km southwest of Paris, monitored greenhouse and reactive gases, as well as aerosols, over 10 years to assess the impact of urban emissions. By comparing downwind and background conditions, the study revealed significant reductions in pollutants linked to traffic: -35.6 % for CO, -52.3 % for NOₓ, -56.7 % for eBC, and -15 % for CO2. These trends align with emission decrease estimates from AIRPARIF inventories over the same period.
Scott D. Chambers, Ute Karstens, Alan D. Griffiths, Stefan Röttger, Arnoud Frumau, Christopher T. Roulston, Peter Sperlich, Felix Vogel, Agnieszka Podstawczyńska, Dafina Kikaj, Maksym Gachkivskyi, Michel Ramonet, Blagoj Mitrevski, Janja Vaupotič, Xuemeng Chen, and Annette Röttger
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This preprint is open for discussion and under review for Atmospheric Measurement Techniques (AMT).
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The Radon Tracer Method (RTM) is a top-down approach to estimate greenhouse gas emissions. While simple in principle, incorrect use can complicate interpretation of results. Based on observations from a range of contrasting sites, this article reviews the underlying assumptions and key considerations for applying the RTM. It also introduces the concept of coupling RTM analyses with nocturnal stability classification, to reduce uncertainty of fetch estimates and improve interpretation of results.
Félix Langot, Cyril Crevoisier, Thomas Lauvaux, Charbel Abdallah, Jérôme Pernin, Xin Lin, Marielle Saunois, Axel Guedj, Thomas Ponthieu, Julien Moyé, Michel Ramonet, Anke Roiger, Klaus-Dirk Gottschaldt, and Alina Fiehn
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This preprint is open for discussion and under review for Atmospheric Chemistry and Physics (ACP).
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Ann-Kristin Kunz, Samuel Hammer, Patrick Aigner, Laura Bignotti, Lars Borchardt, Jia Chen, Julian Della Coletta, Lukas Emmenegger, Markus Eritt, Xochilt Gutiérrez, Josh Hashemi, Rainer Hilland, Christopher Holst, Armin Jordan, Natascha Kljun, Richard Kneißl, Changxing Lan, Virgile Legendre, Ingeborg Levin, Benjamin Loubet, Matthias Mauder, Betty Molinier, Susanne Preunkert, Michel Ramonet, Stavros Stagakis, and Andreas Christen
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This preprint is open for discussion and under review for Atmospheric Chemistry and Physics (ACP).
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This preprint is open for discussion and under review for Atmospheric Chemistry and Physics (ACP).
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We used a regional atmospheric transport model to simulate carbon dioxide mole fractions over Western Europe. The results show the importance of anthropogenic emission configurations, particularly near large emission sources, as well as the necessity of improving biogenic flux simulations. These findings contribute to enhancing the accuracy of carbon dioxide modeling and carbon budget inversions.
Fabian Maier, Eva Falge, Maksym Gachkivskyi, Stephan Henne, Ute Karstens, Dafina Kikaj, Ingeborg Levin, Alistair Manning, Christian Rödenbeck, and Christoph Gerbig
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Carlos Gómez-Ortiz, Guillaume Monteil, Ute Karstens, and Marko Scholze
Atmos. Chem. Phys., 25, 10747–10771, https://doi.org/10.5194/acp-25-10747-2025, https://doi.org/10.5194/acp-25-10747-2025, 2025
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In 2024, an intensive sampling campaign was conducted to improve fossil CO2 emission estimates in Europe using 14C measurements. By testing different strategies for selecting air samples, this study shows that increasing sample frequency and carefully choosing samples based on their fossil fuel and nuclear content leads to more accurate results, reducing the uncertainty and bias of the estimates.
Nikolai Ponomarev, Michael Steiner, Erik Koene, Pascal Rubli, Stuart Grange, Lionel Constantin, Michel Ramonet, Leslie David, Lukas Emmenegger, and Dominik Brunner
EGUsphere, https://doi.org/10.5194/egusphere-2025-3668, https://doi.org/10.5194/egusphere-2025-3668, 2025
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Urban inversions are gaining increasing attention, as cities are major contributors to anthropogenic emissions, making accurate emission estimates at this scale essential for supporting climate action plans and verifying reported emission reductions. We estimated carbon dioxide emissions in Zurich and Paris over one year by combining atmospheric observations with mesoscale model simulations. Our study shows how factors like city size, terrain, and measurement methods affect emission estimates.
Hui Li, Philippe Ciais, Pramod Kumar, Didier A. Hauglustaine, Frédéric Chevallier, Grégoire Broquet, Dylan B. Millet, Kelley C. Wells, Jinghui Lian, and Bo Zheng
Earth Syst. Sci. Data Discuss., https://doi.org/10.5194/essd-2025-424, https://doi.org/10.5194/essd-2025-424, 2025
Preprint under review for ESSD
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We present the first global, multi-year maps of monthly isoprene emissions (2013–2020) derived from satellite isoprene observations, averaging 456 TgC yr-1. The dataset reveals two emission peaks linked to 2015–2016 El Niño and 2019–2020 extreme heat events, driven mainly by tropical regions such as the Amazon. It highlights the region-specific sensitivity of biogenic isoprene emissions to temperature anomalies, providing new insights into their roles in air quality and climate feedbacks.
Constantina Rousogenous, Christof Petri, Pierre-Yves Quehe, Thomas Laemmel, Joshua L. Laughner, Maximilien Desservettaz, Michael Pikridas, Michel Ramonet, Efstratios Bourtsoukidis, Matthias Buschmann, Justus Notholt, Thorsten Warneke, Jean-Daniel Paris, Jean Sciare, and Mihalis Vrekoussis
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The Eastern Mediterranean and Middle East is a greenhouse gas emission hotspot but lacks atmospheric monitoring. Our study introduces the first Total Carbon Column Observing Network site in this region, in Cyprus, providing high-precision columnar measurement of key greenhouse gases. This new dataset enhances global climate monitoring efforts, supports the validation of satellites, will help assess regional emission trends, filling a critical observational gap in this climate-sensitive region.
Adil Shah, Olivier Laurent, Pramod Kumar, Grégoire Broquet, Loïc Loigerot, Timothé Depelchin, Mathis Lozano, Camille Yver Kwok, Carole Philippon, Clément Romand, Elisa Allegrini, Matthieu Trombetti, and Philippe Ciais
Atmos. Meas. Tech., 18, 3425–3451, https://doi.org/10.5194/amt-18-3425-2025, https://doi.org/10.5194/amt-18-3425-2025, 2025
Short summary
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Acetylene mole fraction measurements from the Picarro G2203 were characterised. Abnormal sensor behaviour was observed in wet conditions. A dry linear calibration was derived, although this was invalid below 1.2 ppb due to unstable measurements. The instrument was used to measure acetylene as a methane tracer at a landfill site. Fluxes were derived from 14 downwind transects using both raw and calibrated acetylene mole fraction, with raw measurements resulting in 8 % flux underestimation.
Alessandro Zanchetta, Steven van Heuven, Joram Hooghiem, Rigel Kivi, Thomas Laemmel, Michel Ramonet, Markus Leuenberger, Peter Nyfeler, Sophia Louise Baartman, Maarten Krol, and Huilin Chen
EGUsphere, https://doi.org/10.5194/egusphere-2025-3079, https://doi.org/10.5194/egusphere-2025-3079, 2025
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Continuous vertical profiles and discrete stratospheric samples of carbonyl sulfide (COS) were collected deploying the balloon-borne AirCore, LISA and BigLISA samplers and measured on a Quantum Cascade Laser Spectrometer (QCLS). Our measurements show good accordance with previous COS observations. Moreover, laboratory tests of ozone (O3) scrubbers proved squalene to remove O3 very efficiently without biasing the measurements of other trace gases.
Roger Curcoll, Alba Àgueda, Josep-Anton Morguí, Lídia Cañas, Sílvia Borràs, Arturo Vargas, and Claudia Grossi
Atmos. Chem. Phys., 25, 6299–6323, https://doi.org/10.5194/acp-25-6299-2025, https://doi.org/10.5194/acp-25-6299-2025, 2025
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In this work, the methane emissions from the rice crops of the Ebro Delta were estimated with the Radon Tracer Method, using back trajectories and radon and methane observations. Estimated fluxes show a strong seasonality with maximums in October, corresponding with the period of harvest and straw incorporation. The estimated annual methane emission was about 262.8 kg CH4 ha‑1. Results were compared with fluxes obtained with static chambers showing strong agreement between both methodologies.
Fabien Gibert, Dimitri Edouart, Didier Mondelain, Claire Cénac, and Camille Yver
EGUsphere, https://doi.org/10.5194/egusphere-2025-1039, https://doi.org/10.5194/egusphere-2025-1039, 2025
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This paper presents first differential absorption lidar (DIAL) measurements of isotopic ratio of CO2 (δ13C) in the atmosphere in the spectral domain of 2-µm. This work investigates additional tracers of intra-atmospheric or surface-atmosphere exchanges to characterise CO2 sources and sinks.
Marielle Saunois, Adrien Martinez, Benjamin Poulter, Zhen Zhang, Peter A. Raymond, Pierre Regnier, Josep G. Canadell, Robert B. Jackson, Prabir K. Patra, Philippe Bousquet, Philippe Ciais, Edward J. Dlugokencky, Xin Lan, George H. Allen, David Bastviken, David J. Beerling, Dmitry A. Belikov, Donald R. Blake, Simona Castaldi, Monica Crippa, Bridget R. Deemer, Fraser Dennison, Giuseppe Etiope, Nicola Gedney, Lena Höglund-Isaksson, Meredith A. Holgerson, Peter O. Hopcroft, Gustaf Hugelius, Akihiko Ito, Atul K. Jain, Rajesh Janardanan, Matthew S. Johnson, Thomas Kleinen, Paul B. Krummel, Ronny Lauerwald, Tingting Li, Xiangyu Liu, Kyle C. McDonald, Joe R. Melton, Jens Mühle, Jurek Müller, Fabiola Murguia-Flores, Yosuke Niwa, Sergio Noce, Shufen Pan, Robert J. Parker, Changhui Peng, Michel Ramonet, William J. Riley, Gerard Rocher-Ros, Judith A. Rosentreter, Motoki Sasakawa, Arjo Segers, Steven J. Smith, Emily H. Stanley, Joël Thanwerdas, Hanqin Tian, Aki Tsuruta, Francesco N. Tubiello, Thomas S. Weber, Guido R. van der Werf, Douglas E. J. Worthy, Yi Xi, Yukio Yoshida, Wenxin Zhang, Bo Zheng, Qing Zhu, Qiuan Zhu, and Qianlai Zhuang
Earth Syst. Sci. Data, 17, 1873–1958, https://doi.org/10.5194/essd-17-1873-2025, https://doi.org/10.5194/essd-17-1873-2025, 2025
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Methane (CH4) is the second most important human-influenced greenhouse gas in terms of climate forcing after carbon dioxide (CO2). A consortium of multi-disciplinary scientists synthesise and update the budget of the sources and sinks of CH4. This edition benefits from important progress in estimating emissions from lakes and ponds, reservoirs, and streams and rivers. For the 2010s decade, global CH4 emissions are estimated at 575 Tg CH4 yr-1, including ~65 % from anthropogenic sources.
Ida Storm, Ute Karstens, Claudio D’Onofrio, Alex Vermeulen, Samuel Hammer, Ingrid Super, Theo Glauch, and Wouter Peters
Earth Syst. Sci. Data Discuss., https://doi.org/10.5194/essd-2025-63, https://doi.org/10.5194/essd-2025-63, 2025
Revised manuscript accepted for ESSD
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Many cities are committed to ambitious CO2 emission reduction targets, supported by climate action plans. Atmospheric measurements are essential to verify that these efforts lead to the expected reductions. Here, we characterize and compare 96 European cities across 18 metrics, linking them to four major challenges in CO2 emissions monitoring. Our framework includes a tool with additional cities and metrics, as well as "mapbooks" for the 96 cities.
Sebastien Conil, Gilles Bergametti, Laurent Langrene, Morgan Lopez, Olivier Masson, Cyril Pallares, and Michel Ramonet
EGUsphere, https://doi.org/10.5194/egusphere-2025-148, https://doi.org/10.5194/egusphere-2025-148, 2025
Preprint archived
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From 2012 to 2023, hourly surface ozone, trace gases, meteorological parameters, and weekly beryllium-7 and sodium-22 activity were monitored at the OPE station in eastern France. While mean afternoon ozone concentrations showed no significant trend, baseline ozone increased by 0.7 µg·m⁻³ per year. Ozone anomalies were linked to pollutants (CO, NOx, CH4) from November to February, and to Stratosphere-to-Troposphere Transport proxies from April to September.
Lilian Vallet, Charbel Abdallah, Thomas Lauvaux, Lilian Joly, Michel Ramonet, Philippe Ciais, Morgan Lopez, Irène Xueref-Remy, and Florent Mouillot
Biogeosciences, 22, 213–242, https://doi.org/10.5194/bg-22-213-2025, https://doi.org/10.5194/bg-22-213-2025, 2025
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The 2022 fire season had a huge impact on European temperate forest, with several large fires exhibiting prolonged soil combustion reported. We analyzed CO and CO2 concentration recorded at nearby atmospheric towers, revealing intense smoldering combustion. We refined a fire emission model to incorporate this process. We estimated 7.95 Mteq CO2 fire emission, twice the global estimate. Fires contributed to 1.97 % of France's annual carbon footprint, reducing forest carbon sink by 30 % this year.
Dafina Kikaj, Edward Chung, Alan D. Griffiths, Scott D. Chambers, Grant Forster, Angelina Wenger, Penelope Pickers, Chris Rennick, Simon O'Doherty, Joseph Pitt, Kieran Stanley, Dickon Young, Leigh S. Fleming, Karina Adcock, Emmal Safi, and Tim Arnold
Atmos. Meas. Tech., 18, 151–175, https://doi.org/10.5194/amt-18-151-2025, https://doi.org/10.5194/amt-18-151-2025, 2025
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We present a protocol to improve confidence in atmospheric radon measurements, enabling site comparisons and integration with greenhouse gas data. As a natural tracer, radon provides an independent check of transport model performance. This standardized method enhances radon’s use as a metric for model evaluation. Beyond UK observatories, it can support broader networks like ICOS and WMO/GAW, advancing global atmospheric research.
Pedro Henrique Herig Coimbra, Benjamin Loubet, Olivier Laurent, Laura Bignotti, Mathis Lozano, and Michel Ramonet
Atmos. Meas. Tech., 17, 6625–6645, https://doi.org/10.5194/amt-17-6625-2024, https://doi.org/10.5194/amt-17-6625-2024, 2024
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This study presents direct flux measurements in tall towers using existing slow-response analysers and adding 3D sonic anemometers. This way, we can significantly improve greenhouse gas monitoring with little extra instrumental effort. Slow-response analysers may be used here as the relevant frequency ranges depend on measuring height. Tall towers offer a large footprint, amplifying spatial coverage. The presented concept is a valuable bridge between atmospheric and ecosystem communities.
Marie Lothon, François Gheusi, Fabienne Lohou, Véronique Pont, Serge Soula, Corinne Jambert, Solène Derrien, Yannick Bezombes, Emmanuel Leclerc, Gilles Athier, Antoine Vial, Alban Philibert, Bernard Campistron, Frédérique Saïd, Jeroen Sonke, Julien Amestoy, Erwan Bargain, Pierre Bosser, Damien Boulanger, Guillaume Bret, Renaud Bodichon, Laurent Cabanas, Guylaine Canut, Jean-Bernard Estrampes, Eric Gardrat, Zaida Gomez Kuri, Jérémy Gueffier, Fabienne Guesdon, Morgan Lopez, Olivier Masson, Pierre-Yves Meslin, Yves Meyerfeld, Nicolas Pascal, Eric Pique, Michel Ramonet, Felix Starck, and Romain Vidal
Atmos. Meas. Tech., 17, 6265–6300, https://doi.org/10.5194/amt-17-6265-2024, https://doi.org/10.5194/amt-17-6265-2024, 2024
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The Pyrenean Platform for Observation of the Atmosphere (P2OA) is a coupled plain–mountain instrumented platform in southwestern France for the monitoring of climate variables and the study of meteorological processes in a mountainous region. A comprehensive description of this platform is presented for the first time: its instrumentation, the associated dataset, and a meteorological characterization the site. The potential of the P2OA is illustrated through several examples of process studies.
Noémie Taquet, Wolfgang Stremme, María Eugenia González del Castillo, Victor Almanza, Alejandro Bezanilla, Olivier Laurent, Carlos Alberti, Frank Hase, Michel Ramonet, Thomas Lauvaux, Ke Che, and Michel Grutter
Atmos. Chem. Phys., 24, 11823–11848, https://doi.org/10.5194/acp-24-11823-2024, https://doi.org/10.5194/acp-24-11823-2024, 2024
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We characterize the variability in CO and CO2 emissions over Mexico City from long-term time-resolved Fourier transform infrared spectroscopy solar absorption and surface measurements from 2013 to 2021. Using the average intraday CO growth rate from total columns, the average CO / CO2 ratio and TROPOMI data, we estimate the interannual variability in the CO and CO2 anthropogenic emissions of Mexico City, highlighting the effect of an unprecedented drop in activity due to the COVID-19 lockdown.
Jinghui Lian, Olivier Laurent, Mali Chariot, Luc Lienhardt, Michel Ramonet, Hervé Utard, Thomas Lauvaux, François-Marie Bréon, Grégoire Broquet, Karina Cucchi, Laurent Millair, and Philippe Ciais
Atmos. Meas. Tech., 17, 5821–5839, https://doi.org/10.5194/amt-17-5821-2024, https://doi.org/10.5194/amt-17-5821-2024, 2024
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We have designed and deployed a mid-cost medium-precision CO2 sensor monitoring network in Paris since July 2020. The data are automatically calibrated by a newly implemented data processing system. The accuracies of the mid-cost instruments vary from 1.0 to 2.4 ppm for hourly afternoon measurements. Our model–data analyses highlight prospects for integrating mid-cost instrument data with high-precision measurements to improve fine-scale CO2 emission quantification in urban areas.
Josselin Doc, Michel Ramonet, François-Marie Bréon, Delphine Combaz, Mali Chariot, Morgan Lopez, Marc Delmotte, Cristelle Cailteau-Fischbach, Guillaume Nief, Nathanaël Laporte, Thomas Lauvaux, and Philippe Ciais
EGUsphere, https://doi.org/10.5194/egusphere-2024-2826, https://doi.org/10.5194/egusphere-2024-2826, 2024
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Description of the network for measuring greenhouse gas concentrations in the Paris region and analysis of eight years of continuous monitoring.
Pierre Tulet, Joel Van Baelen, Pierre Bosser, Jérome Brioude, Aurélie Colomb, Philippe Goloub, Andrea Pazmino, Thierry Portafaix, Michel Ramonet, Karine Sellegri, Melilotus Thyssen, Léa Gest, Nicolas Marquestaut, Dominique Mékiès, Jean-Marc Metzger, Gilles Athier, Luc Blarel, Marc Delmotte, Guillaume Desprairies, Mérédith Dournaux, Gaël Dubois, Valentin Duflot, Kevin Lamy, Lionel Gardes, Jean-François Guillemot, Valérie Gros, Joanna Kolasinski, Morgan Lopez, Olivier Magand, Erwan Noury, Manuel Nunes-Pinharanda, Guillaume Payen, Joris Pianezze, David Picard, Olivier Picard, Sandrine Prunier, François Rigaud-Louise, Michael Sicard, and Benjamin Torres
Earth Syst. Sci. Data, 16, 3821–3849, https://doi.org/10.5194/essd-16-3821-2024, https://doi.org/10.5194/essd-16-3821-2024, 2024
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The MAP-IO program aims to compensate for the lack of atmospheric and oceanographic observations in the Southern Ocean by equipping the ship Marion Dufresne with a set of 17 scientific instruments. This program collected 700 d of measurements under different latitudes, seasons, sea states, and weather conditions. These new data will support the calibration and validation of numerical models and the understanding of the atmospheric composition of this region of Earth.
Rodrigo Rivera-Martinez, Pramod Kumar, Olivier Laurent, Gregoire Broquet, Christopher Caldow, Ford Cropley, Diego Santaren, Adil Shah, Cécile Mallet, Michel Ramonet, Leonard Rivier, Catherine Juery, Olivier Duclaux, Caroline Bouchet, Elisa Allegrini, Hervé Utard, and Philippe Ciais
Atmos. Meas. Tech., 17, 4257–4290, https://doi.org/10.5194/amt-17-4257-2024, https://doi.org/10.5194/amt-17-4257-2024, 2024
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We explore the use of metal oxide semiconductors (MOSs) as a low-cost alternative for detecting and measuring CH4 emissions from industrial facilities. MOSs were exposed to several controlled releases to test their accuracy in detecting and quantifying emissions. Two reconstruction models were compared, and emission estimates were computed using a Gaussian dispersion model. Findings show that MOSs can provide accurate emission estimates with a 25 % emission rate error and a 9.5 m location error.
Roger Curcoll, Claudia Grossi, Stefan Röttger, and Arturo Vargas
Atmos. Meas. Tech., 17, 3047–3065, https://doi.org/10.5194/amt-17-3047-2024, https://doi.org/10.5194/amt-17-3047-2024, 2024
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This paper presents a new user-friendly version of the Atmospheric Radon MONitor (ARMON). The efficiency of the instrument is of 0.0057 s-1, obtained using different techniques at Spanish and German chambers. The total calculated uncertainty of the ARMON for hourly radon concentrations above 5 Bq m-3 is lower than 10 % (k = 1). Results confirm that the ARMON is suitable to measure low-level radon activity concentrations and to be used as a transfer standard to calibrate in situ radon monitors.
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.
Zhendong Wu, Alex Vermeulen, Yousuke Sawa, Ute Karstens, Wouter Peters, Remco de Kok, Xin Lan, Yasuyuki Nagai, Akinori Ogi, and Oksana Tarasova
Atmos. Chem. Phys., 24, 1249–1264, https://doi.org/10.5194/acp-24-1249-2024, https://doi.org/10.5194/acp-24-1249-2024, 2024
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This study focuses on exploring the differences in calculating global surface CO2 and its growth rate, considering the impact of analysis methodologies and site selection. Our study reveals that the current global CO2 network has a good capacity to represent global surface CO2 and its growth rate, as well as trends in atmospheric CO2 mass changes. However, small differences exist in different analyses due to the impact of methodology and site selection.
Paolo Cristofanelli, Cosimo Fratticioli, Lynn Hazan, Mali Chariot, Cedric Couret, Orestis Gazetas, Dagmar Kubistin, Antti Laitinen, Ari Leskinen, Tuomas Laurila, Matthias Lindauer, Giovanni Manca, Michel Ramonet, Pamela Trisolino, and Martin Steinbacher
Atmos. Meas. Tech., 16, 5977–5994, https://doi.org/10.5194/amt-16-5977-2023, https://doi.org/10.5194/amt-16-5977-2023, 2023
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We investigated the application of two automatic methods for detecting spikes due to local emissions in greenhouse gas (GHG) observations at a subset of sites from the ICOS Atmosphere network. We analysed the sensitivity to the spike frequency of using different methods and settings. We documented the impact of the de-spiking on different temporal aggregations (i.e. hourly, monthly and seasonal averages) of CO2, CH4 and CO 1 min time series.
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.
Ioannis Cheliotis, Thomas Lauvaux, Jinghui Lian, Theodoros Christoudias, George Georgiou, Alba Badia, Frédéric Chevallier, Pramod Kumar, Yathin Kudupaje, Ruixue Lei, and Philippe Ciais
EGUsphere, https://doi.org/10.5194/egusphere-2023-2487, https://doi.org/10.5194/egusphere-2023-2487, 2023
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A consistent estimation of CO2 emissions is complicated due to the scarcity of CO2 observations. In this study, we showcase the potential to improve the CO2 emissions estimations from the NO2 concentrations based on the NO2-to-CO2 ratio, which should be constant for a source co-emitting NO2 and CO2, by comparing satellite observations with atmospheric chemistry and transport model simulations for NO2 and CO2. Furthermore, we demonstrate the significance of the chemistry in NO2 simulations.
Alba Badia, Veronica Vidal, Sergi Ventura, Roger Curcoll, Ricard Segura, and Gara Villalba
Atmos. Chem. Phys., 23, 10751–10774, https://doi.org/10.5194/acp-23-10751-2023, https://doi.org/10.5194/acp-23-10751-2023, 2023
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Improving air quality is a top priority in urban areas. In this study, we used an air quality model to analyse the air quality changes occurring over the metropolitan area of Barcelona and other rural areas affected by transport of the atmospheric plume from the city during mobility restrictions. Our results show that mitigation strategies intended to reduce O3 should be designed according to the local meteorology, air transport, and particular ozone chemistry of the urban area.
Alessandro Zanchetta, Linda M. J. Kooijmans, Steven van Heuven, Andrea Scifo, Hubertus A. Scheeren, Ivan Mammarella, Ute Karstens, Jin Ma, Maarten Krol, and Huilin Chen
Biogeosciences, 20, 3539–3553, https://doi.org/10.5194/bg-20-3539-2023, https://doi.org/10.5194/bg-20-3539-2023, 2023
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Carbonyl sulfide (COS) has been suggested as a tool to estimate carbon dioxide (CO2) uptake by plants during photosynthesis. However, understanding its sources and sinks is critical to preventing biases in this estimate. Combining observations and models, this study proves that regional sources occasionally influence the measurements at the 60 m tall Lutjewad tower (1 m a.s.l.; 53°24′ N, 6°21′ E) in the Netherlands. Moreover, it estimates nighttime COS fluxes to be −3.0 ± 2.6 pmol m−2 s−1.
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.
Jinghui Lian, Thomas Lauvaux, Hervé Utard, François-Marie Bréon, Grégoire Broquet, Michel Ramonet, Olivier Laurent, Ivonne Albarus, Mali Chariot, Simone Kotthaus, Martial Haeffelin, Olivier Sanchez, Olivier Perrussel, Hugo Anne Denier van der Gon, Stijn Nicolaas Camiel Dellaert, and Philippe Ciais
Atmos. Chem. Phys., 23, 8823–8835, https://doi.org/10.5194/acp-23-8823-2023, https://doi.org/10.5194/acp-23-8823-2023, 2023
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This study quantifies urban CO2 emissions via an atmospheric inversion for the Paris metropolitan area over a 6-year period from 2016 to 2021. Results show a long-term decreasing trend of about 2 % ± 0.6 % per year in the annual CO2 emissions over Paris. We conclude that our current capacity can deliver near-real-time CO2 emission estimates at the city scale in under a month, and the results agree within 10 % with independent estimates from multiple city-scale inventories.
Joffrey Dumont Le Brazidec, Pierre Vanderbecken, Alban Farchi, Marc Bocquet, Jinghui Lian, Grégoire Broquet, Gerrit Kuhlmann, Alexandre Danjou, and Thomas Lauvaux
Geosci. Model Dev., 16, 3997–4016, https://doi.org/10.5194/gmd-16-3997-2023, https://doi.org/10.5194/gmd-16-3997-2023, 2023
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Monitoring of CO2 emissions is key to the development of reduction policies. Local emissions, from cities or power plants, may be estimated from CO2 plumes detected in satellite images. CO2 plumes generally have a weak signal and are partially concealed by highly variable background concentrations and instrument errors, which hampers their detection. To address this problem, we propose and apply deep learning methods to detect the contour of a plume in simulated CO2 satellite images.
Claudia Grossi, Daniel Rabago, Scott Chambers, Carlos Sáinz, Roger Curcoll, Peter P. S. Otáhal, Eliška Fialová, Luis Quindos, and Arturo Vargas
Atmos. Meas. Tech., 16, 2655–2672, https://doi.org/10.5194/amt-16-2655-2023, https://doi.org/10.5194/amt-16-2655-2023, 2023
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The automatic and low-maintenance radon flux system Autoflux, completed with environmental soil and atmosphere sensors, has been theoretically and experimentally characterized and calibrated under laboratory conditions to be used as transfer standard for in situ measurements. It will offer for the first time long-term measurements to validate radon flux maps used by the climate and the radiation protection communities for assessing the radon gas emissions in the atmosphere.
Ida Storm, Ute Karstens, Claudio D'Onofrio, Alex Vermeulen, and Wouter Peters
Atmos. Chem. Phys., 23, 4993–5008, https://doi.org/10.5194/acp-23-4993-2023, https://doi.org/10.5194/acp-23-4993-2023, 2023
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In this study, we evaluate what is in the influence regions of the ICOS atmospheric measurement stations to gain insight into what land cover types and land-cover-associated fluxes the network represents. Subsequently, insights about strengths, weaknesses, and potential gaps can assist in future network expansion decisions. The network is concentrated in central Europe, which leads to a general overrepresentation of coniferous forest and cropland and underrepresentation of grass and shrubland.
Rodrigo Andres Rivera Martinez, Diego Santaren, Olivier Laurent, Gregoire Broquet, Ford Cropley, Cécile Mallet, Michel Ramonet, Adil Shah, Leonard Rivier, Caroline Bouchet, Catherine Juery, Olivier Duclaux, and Philippe Ciais
Atmos. Meas. Tech., 16, 2209–2235, https://doi.org/10.5194/amt-16-2209-2023, https://doi.org/10.5194/amt-16-2209-2023, 2023
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A network of low-cost sensors is a good alternative to improve the detection of fugitive CH4 emissions. We present the results of four tests conducted with two types of Figaro sensors that were assembled on four chambers in a laboratory experiment: a comparison of five models to reconstruct the CH4 signal, a strategy to reduce the training set size, a detection of age effects in the sensors and a test of the capability to transfer a model between chambers for the same type of sensor.
Anna Agustí-Panareda, Jérôme Barré, Sébastien Massart, Antje Inness, Ilse Aben, Melanie Ades, Bianca C. Baier, Gianpaolo Balsamo, Tobias Borsdorff, Nicolas Bousserez, Souhail Boussetta, Michael Buchwitz, Luca Cantarello, Cyril Crevoisier, Richard Engelen, Henk Eskes, Johannes Flemming, Sébastien Garrigues, Otto Hasekamp, Vincent Huijnen, Luke Jones, Zak Kipling, Bavo Langerock, Joe McNorton, Nicolas Meilhac, Stefan Noël, Mark Parrington, Vincent-Henri Peuch, Michel Ramonet, Miha Razinger, Maximilian Reuter, Roberto Ribas, Martin Suttie, Colm Sweeney, Jérôme Tarniewicz, and Lianghai Wu
Atmos. Chem. Phys., 23, 3829–3859, https://doi.org/10.5194/acp-23-3829-2023, https://doi.org/10.5194/acp-23-3829-2023, 2023
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We present a global dataset of atmospheric CO2 and CH4, the two most important human-made greenhouse gases, which covers almost 2 decades (2003–2020). It is produced by combining satellite data of CO2 and CH4 with a weather and air composition prediction model, and it has been carefully evaluated against independent observations to ensure validity and point out deficiencies to the user. This dataset can be used for scientific studies in the field of climate change and the global carbon cycle.
Saqr Munassar, Guillaume Monteil, Marko Scholze, Ute Karstens, Christian Rödenbeck, Frank-Thomas Koch, Kai U. Totsche, and Christoph Gerbig
Atmos. Chem. Phys., 23, 2813–2828, https://doi.org/10.5194/acp-23-2813-2023, https://doi.org/10.5194/acp-23-2813-2023, 2023
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Using different transport models results in large errors in optimized fluxes in the atmospheric inversions. Boundary conditions and inversion system configurations lead to a smaller but non-negligible impact. The findings highlight the importance to validate transport models for further developments but also to properly account for such errors in inverse modelling. This will help narrow the convergence of gas estimates reported in the scientific literature from different inversion frameworks.
Auke M. van der Woude, Remco de Kok, Naomi Smith, Ingrid T. Luijkx, Santiago Botía, Ute Karstens, Linda M. J. Kooijmans, Gerbrand Koren, Harro A. J. Meijer, Gert-Jan Steeneveld, Ida Storm, Ingrid Super, Hubertus A. Scheeren, Alex Vermeulen, and Wouter Peters
Earth Syst. Sci. Data, 15, 579–605, https://doi.org/10.5194/essd-15-579-2023, https://doi.org/10.5194/essd-15-579-2023, 2023
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To monitor the progress towards the CO2 emission goals set out in the Paris Agreement, the European Union requires an independent validation of emitted CO2. For this validation, atmospheric measurements of CO2 can be used, together with first-guess estimates of CO2 emissions and uptake. To quickly inform end users, it is imperative that this happens in near real-time. To aid these efforts, we create estimates of European CO2 exchange at high resolution in near real time.
Alkuin M. Koenig, Olivier Magand, Bert Verreyken, Jerome Brioude, Crist Amelynck, Niels Schoon, Aurélie Colomb, Beatriz Ferreira Araujo, Michel Ramonet, Mahesh K. Sha, Jean-Pierre Cammas, Jeroen E. Sonke, and Aurélien Dommergue
Atmos. Chem. Phys., 23, 1309–1328, https://doi.org/10.5194/acp-23-1309-2023, https://doi.org/10.5194/acp-23-1309-2023, 2023
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The global distribution of mercury, a potent neurotoxin, depends on atmospheric transport, chemistry, and interactions between the Earth’s surface and the air. Our understanding of these processes is still hampered by insufficient observations. Here, we present new data from a mountain observatory in the Southern Hemisphere. We give insights into mercury concentrations in air masses coming from aloft, and we show that tropical mountain vegetation may be a daytime source of mercury to the air.
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.
Simone M. Pieber, Béla Tuzson, Stephan Henne, Ute Karstens, Christoph Gerbig, Frank-Thomas Koch, Dominik Brunner, Martin Steinbacher, and Lukas Emmenegger
Atmos. Chem. Phys., 22, 10721–10749, https://doi.org/10.5194/acp-22-10721-2022, https://doi.org/10.5194/acp-22-10721-2022, 2022
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Understanding regional greenhouse gas emissions into the atmosphere is a prerequisite to mitigate climate change. In this study, we investigated the regional contributions of carbon dioxide (CO2) at the location of the high Alpine observatory Jungfraujoch (JFJ, Switzerland, 3580 m a.s.l.). To this purpose, we combined receptor-oriented atmospheric transport simulations for CO2 concentration in the period 2009–2017 with stable carbon isotope (δ13C–CO2) information.
Matthias Schneider, Benjamin Ertl, Qiansi Tu, Christopher J. Diekmann, Farahnaz Khosrawi, Amelie N. Röhling, Frank Hase, Darko Dubravica, Omaira E. García, Eliezer Sepúlveda, Tobias Borsdorff, Jochen Landgraf, Alba Lorente, André Butz, Huilin Chen, Rigel Kivi, Thomas Laemmel, Michel Ramonet, Cyril Crevoisier, Jérome Pernin, Martin Steinbacher, Frank Meinhardt, Kimberly Strong, Debra Wunch, Thorsten Warneke, Coleen Roehl, Paul O. Wennberg, Isamu Morino, Laura T. Iraci, Kei Shiomi, Nicholas M. Deutscher, David W. T. Griffith, Voltaire A. Velazco, and David F. Pollard
Atmos. Meas. Tech., 15, 4339–4371, https://doi.org/10.5194/amt-15-4339-2022, https://doi.org/10.5194/amt-15-4339-2022, 2022
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We present a computationally very efficient method for the synergetic use of level 2 remote-sensing data products. We apply the method to IASI vertical profile and TROPOMI total column space-borne methane observations and thus gain sensitivity for the tropospheric methane partial columns, which is not achievable by the individual use of TROPOMI and IASI. These synergetic effects are evaluated theoretically and empirically by inter-comparisons to independent references of TCCON, AirCore, and GAW.
Sieglinde Callewaert, Jérôme Brioude, Bavo Langerock, Valentin Duflot, Dominique Fonteyn, Jean-François Müller, Jean-Marc Metzger, Christian Hermans, Nicolas Kumps, Michel Ramonet, Morgan Lopez, Emmanuel Mahieu, and Martine De Mazière
Atmos. Chem. Phys., 22, 7763–7792, https://doi.org/10.5194/acp-22-7763-2022, https://doi.org/10.5194/acp-22-7763-2022, 2022
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A regional atmospheric transport model is used to analyze the factors contributing to CO2, CH4, and CO observations at Réunion Island. We show that the surface observations are dominated by local fluxes and dynamical processes, while the column data are influenced by larger-scale mechanisms such as biomass burning plumes. The model is able to capture the measured time series well; however, the results are highly dependent on accurate boundary conditions and high-resolution emission inventories.
Roger Curcoll, Josep-Anton Morguí, Armand Kamnang, Lídia Cañas, Arturo Vargas, and Claudia Grossi
Atmos. Meas. Tech., 15, 2807–2818, https://doi.org/10.5194/amt-15-2807-2022, https://doi.org/10.5194/amt-15-2807-2022, 2022
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Low-cost air enquirer kits, including CO2 and environmental parameter sensors, have been designed, built, and tested in a new steady-state through-flow chamber for simultaneous measurements of CO2 fluxes in soil and CO2 concentrations in air. A CO2 calibration and multiparametric fitting reduced the total uncertainty of CO2 concentration by 90 %. This system allows continuous measurement of CO2 fluxes and CO2 ambient air, with low cost (EUR 1200), low energy demand (<5 W), and low maintenance.
Carlos Alberti, Frank Hase, Matthias Frey, Darko Dubravica, Thomas Blumenstock, Angelika Dehn, Paolo Castracane, Gregor Surawicz, Roland Harig, Bianca C. Baier, Caroline Bès, Jianrong Bi, Hartmut Boesch, André Butz, Zhaonan Cai, Jia Chen, Sean M. Crowell, Nicholas M. Deutscher, Dragos Ene, Jonathan E. Franklin, Omaira García, David Griffith, Bruno Grouiez, Michel Grutter, Abdelhamid Hamdouni, Sander Houweling, Neil Humpage, Nicole Jacobs, Sujong Jeong, Lilian Joly, Nicholas B. Jones, Denis Jouglet, Rigel Kivi, Ralph Kleinschek, Morgan Lopez, Diogo J. Medeiros, Isamu Morino, Nasrin Mostafavipak, Astrid Müller, Hirofumi Ohyama, Paul I. Palmer, Mahesh Pathakoti, David F. Pollard, Uwe Raffalski, Michel Ramonet, Robbie Ramsay, Mahesh Kumar Sha, Kei Shiomi, William Simpson, Wolfgang Stremme, Youwen Sun, Hiroshi Tanimoto, Yao Té, Gizaw Mengistu Tsidu, Voltaire A. Velazco, Felix Vogel, Masataka Watanabe, Chong Wei, Debra Wunch, Marcia Yamasoe, Lu Zhang, and Johannes Orphal
Atmos. Meas. Tech., 15, 2433–2463, https://doi.org/10.5194/amt-15-2433-2022, https://doi.org/10.5194/amt-15-2433-2022, 2022
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Space-borne greenhouse gas missions require ground-based validation networks capable of providing fiducial reference measurements. Here, considerable refinements of the calibration procedures for the COllaborative Carbon Column Observing Network (COCCON) are presented. Laboratory and solar side-by-side procedures for the characterization of the spectrometers have been refined and extended. Revised calibration factors for XCO2, XCO and XCH4 are provided, incorporating 47 new spectrometers.
Stefan Röttger, Annette Röttger, Claudia Grossi, Arturo Vargas, Ute Karstens, Giorgia Cinelli, Edward Chung, Dafina Kikaj, Chris Rennick, Florian Mertes, and Ileana Radulescu
Adv. Geosci., 57, 37–47, https://doi.org/10.5194/adgeo-57-37-2022, https://doi.org/10.5194/adgeo-57-37-2022, 2022
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Radon gas is the largest source of public exposure to naturally occurring radioactivity. Radon can also be used, as a tracer to improve indirectly the estimates of greenhouse gases important for supporting successful GHG mitigation strategies.
Both climate and radiation protection research communities need improved traceable low-level atmospheric radon measurements. The EMPIR project 19ENV01 traceRadon started to provide the necessary measurement infrastructure and transfer standards.
Ingeborg Levin, Ute Karstens, Samuel Hammer, Julian DellaColetta, Fabian Maier, and Maksym Gachkivskyi
Atmos. Chem. Phys., 21, 17907–17926, https://doi.org/10.5194/acp-21-17907-2021, https://doi.org/10.5194/acp-21-17907-2021, 2021
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The radon tracer method is applied to atmospheric methane and radon observations from the upper Rhine valley to independently estimate methane emissions from the region. Comparison of our top-down results with bottom-up inventory data requires high-resolution footprint modelling and representative radon flux data. In agreement with inventories, observed emissions decreased, but only until 2005. A limitation of this method is that point-source emissions are not captured or not fully captured.
Alex Resovsky, Michel Ramonet, Leonard Rivier, Jerome Tarniewicz, Philippe Ciais, Martin Steinbacher, Ivan Mammarella, Meelis Mölder, Michal Heliasz, Dagmar Kubistin, Matthias Lindauer, Jennifer Müller-Williams, Sebastien Conil, and Richard Engelen
Atmos. Meas. Tech., 14, 6119–6135, https://doi.org/10.5194/amt-14-6119-2021, https://doi.org/10.5194/amt-14-6119-2021, 2021
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We present a technical description of a statistical methodology for extracting synoptic- and seasonal-length anomalies from greenhouse gas time series. The definition of what represents an anomalous signal is somewhat subjective, which we touch on throughout the paper. We show, however, that the method performs reasonably well in extracting portions of time series influenced by significant North Atlantic Oscillation weather episodes and continent-wide terrestrial biospheric aberrations.
Pramod Kumar, Grégoire Broquet, Camille Yver-Kwok, Olivier Laurent, Susan Gichuki, Christopher Caldow, Ford Cropley, Thomas Lauvaux, Michel Ramonet, Guillaume Berthe, Frédéric Martin, Olivier Duclaux, Catherine Juery, Caroline Bouchet, and Philippe Ciais
Atmos. Meas. Tech., 14, 5987–6003, https://doi.org/10.5194/amt-14-5987-2021, https://doi.org/10.5194/amt-14-5987-2021, 2021
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This study presents a simple atmospheric inversion modeling framework for the localization and quantification of unknown CH4 and CO2 emissions from point sources based on near-surface mobile concentration measurements and a Gaussian plume dispersion model. It is applied for the estimate of a series of brief controlled releases of CH4 and CO2 with a wide range of rates during the TOTAL TADI-2018 experiment. Results indicate a ~10 %–40 % average error on the estimate of the release rates.
Antoine Berchet, Espen Sollum, Rona L. Thompson, Isabelle Pison, Joël Thanwerdas, Grégoire Broquet, Frédéric Chevallier, Tuula Aalto, Adrien Berchet, Peter Bergamaschi, Dominik Brunner, Richard Engelen, Audrey Fortems-Cheiney, Christoph Gerbig, Christine D. Groot Zwaaftink, Jean-Matthieu Haussaire, Stephan Henne, Sander Houweling, Ute Karstens, Werner L. Kutsch, Ingrid T. Luijkx, Guillaume Monteil, Paul I. Palmer, Jacob C. A. van Peet, Wouter Peters, Philippe Peylin, Elise Potier, Christian Rödenbeck, Marielle Saunois, Marko Scholze, Aki Tsuruta, and Yuanhong Zhao
Geosci. Model Dev., 14, 5331–5354, https://doi.org/10.5194/gmd-14-5331-2021, https://doi.org/10.5194/gmd-14-5331-2021, 2021
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We present here the Community Inversion Framework (CIF) to help rationalize development efforts and leverage the strengths of individual inversion systems into a comprehensive framework. The CIF is a programming protocol to allow various inversion bricks to be exchanged among researchers.
The ensemble of bricks makes a flexible, transparent and open-source Python-based tool. We describe the main structure and functionalities and demonstrate it in a simple academic case.
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.
Jinghui Lian, François-Marie Bréon, Grégoire Broquet, Thomas Lauvaux, Bo Zheng, Michel Ramonet, Irène Xueref-Remy, Simone Kotthaus, Martial Haeffelin, and Philippe Ciais
Atmos. Chem. Phys., 21, 10707–10726, https://doi.org/10.5194/acp-21-10707-2021, https://doi.org/10.5194/acp-21-10707-2021, 2021
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Currently there is growing interest in monitoring city-scale CO2 emissions based on atmospheric CO2 measurements, atmospheric transport modeling, and inversion technique. We analyze the various sources of uncertainty that impact the atmospheric CO2 modeling and that may compromise the potential of this method for the monitoring of CO2 emission over Paris. Results suggest selection criteria for the assimilation of CO2 measurements into the inversion system that aims at retrieving city emissions.
Ana Maria Roxana Petrescu, Matthew J. McGrath, Robbie M. Andrew, Philippe Peylin, Glen P. Peters, Philippe Ciais, Gregoire Broquet, Francesco N. Tubiello, Christoph Gerbig, Julia Pongratz, Greet Janssens-Maenhout, Giacomo Grassi, Gert-Jan Nabuurs, Pierre Regnier, Ronny Lauerwald, Matthias Kuhnert, Juraj Balkovič, Mart-Jan Schelhaas, Hugo A. C. Denier van der
Gon, Efisio Solazzo, Chunjing Qiu, Roberto Pilli, Igor B. Konovalov, Richard A. Houghton, Dirk Günther, Lucia Perugini, Monica Crippa, Raphael Ganzenmüller, Ingrid T. Luijkx, Pete Smith, Saqr Munassar, Rona L. Thompson, Giulia Conchedda, Guillaume Monteil, Marko Scholze, Ute Karstens, Patrick Brockmann, and Albertus Johannes Dolman
Earth Syst. Sci. Data, 13, 2363–2406, https://doi.org/10.5194/essd-13-2363-2021, https://doi.org/10.5194/essd-13-2363-2021, 2021
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This study is topical and provides a state-of-the-art scientific overview of data availability from bottom-up and top-down CO2 fossil emissions and CO2 land fluxes in the EU27+UK. The data integrate recent emission inventories with ecosystem data, land carbon models and regional/global inversions for the European domain, aiming at reconciling CO2 estimates with official country-level UNFCCC national GHG inventories in support to policy and facilitating real-time verification procedures.
Alkuin Maximilian Koenig, Olivier Magand, Paolo Laj, Marcos Andrade, Isabel Moreno, Fernando Velarde, Grover Salvatierra, René Gutierrez, Luis Blacutt, Diego Aliaga, Thomas Reichler, Karine Sellegri, Olivier Laurent, Michel Ramonet, and Aurélien Dommergue
Atmos. Chem. Phys., 21, 3447–3472, https://doi.org/10.5194/acp-21-3447-2021, https://doi.org/10.5194/acp-21-3447-2021, 2021
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The environmental cycling of atmospheric mercury, a harmful global contaminant, is still not sufficiently constrained, partly due to missing data in remote regions. Here, we address this issue by presenting 20 months of atmospheric mercury measurements, sampled in the Bolivian Andes. We observe a significant seasonal pattern, whose key features we explore. Moreover, we deduce ratios to constrain South American biomass burning mercury emissions and the mercury uptake by the Amazon rainforest.
Shamil Maksyutov, Tomohiro Oda, Makoto Saito, Rajesh Janardanan, Dmitry Belikov, Johannes W. Kaiser, Ruslan Zhuravlev, Alexander Ganshin, Vinu K. Valsala, Arlyn Andrews, Lukasz Chmura, Edward Dlugokencky, László Haszpra, Ray L. Langenfelds, Toshinobu Machida, Takakiyo Nakazawa, Michel Ramonet, Colm Sweeney, and Douglas Worthy
Atmos. Chem. Phys., 21, 1245–1266, https://doi.org/10.5194/acp-21-1245-2021, https://doi.org/10.5194/acp-21-1245-2021, 2021
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In order to improve the top-down estimation of the anthropogenic greenhouse gas emissions, a high-resolution inverse modelling technique was developed for applications to global transport modelling of carbon dioxide and other greenhouse gases. A coupled Eulerian–Lagrangian transport model and its adjoint are combined with surface fluxes at 0.1° resolution to provide high-resolution forward simulation and inverse modelling of surface fluxes accounting for signals from emission hot spots.
Camille Yver-Kwok, Carole Philippon, Peter Bergamaschi, Tobias Biermann, Francescopiero Calzolari, Huilin Chen, Sebastien Conil, Paolo Cristofanelli, Marc Delmotte, Juha Hatakka, Michal Heliasz, Ove Hermansen, Kateřina Komínková, Dagmar Kubistin, Nicolas Kumps, Olivier Laurent, Tuomas Laurila, Irene Lehner, Janne Levula, Matthias Lindauer, Morgan Lopez, Ivan Mammarella, Giovanni Manca, Per Marklund, Jean-Marc Metzger, Meelis Mölder, Stephen M. Platt, Michel Ramonet, Leonard Rivier, Bert Scheeren, Mahesh Kumar Sha, Paul Smith, Martin Steinbacher, Gabriela Vítková, and Simon Wyss
Atmos. Meas. Tech., 14, 89–116, https://doi.org/10.5194/amt-14-89-2021, https://doi.org/10.5194/amt-14-89-2021, 2021
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The Integrated Carbon Observation System (ICOS) is a pan-European research infrastructure which provides harmonized and high-precision scientific data on the carbon cycle and the greenhouse gas (GHG) budget. All stations have to undergo a rigorous assessment before being labeled, i.e., receiving approval to join the network. In this paper, we present the labeling process for the ICOS atmospheric network through the 23 stations that were labeled between November 2017 and November 2019.
Cited articles
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Ahmadov, R., Gerbig, C., Kretschmer, R., Körner, S., Rödenbeck, C., Bousquet, P., and Ramonet, M.: Comparing high resolution WRF-VPRM simulations and two global CO2 transport models with coastal tower measurements of CO2, Biogeosciences, 6, 807–817, https://doi.org/10.5194/bg-6-807-2009, 2009. a
Ammoura, L., Xueref-Remy, I., Gros, V., Baudic, A., Bonsang, B., Petit, J.-E., Perrussel, O., Bonnaire, N., Sciare, J., and Chevallier, F.: Atmospheric measurements of ratios between CO2 and co-emitted species from traffic: a tunnel study in the Paris megacity, Atmos. Chem. Phys., 14, 12871–12882, https://doi.org/10.5194/acp-14-12871-2014, 2014. a
Ammoura, L., Xueref-Remy, I., Vogel, F., Gros, V., Baudic, A., Bonsang, B., Delmotte, M., Té, Y., and Chevallier, F.: Exploiting stagnant conditions to derive robust emission ratio estimates for CO2, CO and volatile organic compounds in Paris, Atmos. Chem. Phys., 16, 15653–15664, https://doi.org/10.5194/acp-16-15653-2016, 2016. a
Andrews, A. E., Kofler, J. D., Trudeau, M. E., Williams, J. C., Neff, D. H., Masarie, K. A., Chao, D. Y., Kitzis, D. R., Novelli, P. C., Zhao, C. L., Dlugokencky, E. J., Lang, P. M., Crotwell, M. J., Fischer, M. L., Parker, M. J., Lee, J. T., Baumann, D. D., Desai, A. R., Stanier, C. O., De Wekker, S. F. J., Wolfe, D. E., Munger, J. W., and Tans, P. P.: CO2, CO, and CH4 measurements from tall towers in the NOAA Earth System Research Laboratory's Global Greenhouse Gas Reference Network: instrumentation, uncertainty analysis, and recommendations for future high-accuracy greenhouse gas monitoring efforts, Atmos. Meas. Tech., 7, 647–687, https://doi.org/10.5194/amt-7-647-2014, 2014. a
Beaudoing, H. and Rodell, M.: GLDAS Noah Land Surface Model L4 monthly 1.0 × 1.0 degree V2.1, GES DISC, https://doi.org/10.5067/LWTYSMP3VM5Z, 2020. a
Belviso, S., Schmidt, M., Yver, C., Ramonet, M., Gros, V., and Launois, T.: Strong similarities between night-time deposition velocities of carbonyl sulphide and molecular hydrogen inferred from semi-continuous atmospheric observations in Gif-sur-Yvette, Paris region, Tellus B, https://doi.org/10.3402/tellusb.v65i0.20719, 2013. a, b, c
Belviso, S., Lebegue, B., Ramonet, M., Kazan, V., Pison, I., Berchet, A., Delmotte, M., Yver-Kwok, C., Montagne, D., and Ciais, P.: A top-down approach of sources and non-photosynthetic sinks of carbonyl sulfide from atmospheric measurements over multiple years in the Paris region (France), PLOS ONE, https://doi.org/10.1371/journal.pone.0228419, 2020. a, b, c
Belviso, S., Abadie, C., Montagne, D., Hadjar, D., Tropée, D., Vialettes, L., Kazan, V., Delmotte, M., Maignan, F., Remaud, M., Ramonet, M., Lopez, M., Yver-Kwok, C., and Ciais, P.: Carbonyl sulfide (COS) emissions in two agroecosystems in central France, Le Centre pour la Communication Scientifique Directe – HAL – Inria, Plos One, https://doi.org/10.1371/journal.pone.0278584, 2022. a, b
Bergamaschi, P., Danila, A., Weiss, R. F., Ciais, P., Thompson, R. L., Brunner, D., Levin, I., Meijer, Y., Chevallier, F., Janssens-Maenhout, G., Bovensmann, H., Crisp, D., Basu, S., Dlugokencky, E., Engelen, R., Gerbig, C., Günther, D., Hammer, S., Henne, S., Houweling, S., Karstens, U., Kort, E., Maione, M., Manning, A. J., Miller, J., Montzka, S., Pandey, S., Peters, W., Peylin, P., Pinty, B., Ramonet, M., Reimann, S., Röckmann, T., Schmidt, M., Strogies, M., Sussams, J., Tarasova, O., van Aardenne, J., Vermeulen, A. T., and Vogel, F.: Atmospheric monitoring and inverse modelling for verification of greenhouse gas inventories, Office of the European Union, https://doi.org/10.2760/02681, 2018. a, b
Biraud, S. C., Ciais, P., Ramonet, M., Simmonds, P., Kazan, V., Monfray, P., O'Doherty, S., Spain, T. G., and Jennings, S. G.: European greenhouse gas emissions estimated from continuous atmospheric measurements and radon 222 at Mace Head, Ireland, Journal of Geophysical Research, https://doi.org/10.1029/1999jd900821, 2000. a, b, c, d
Brioude, J., Arnold, D., Stohl, A., Cassiani, M., Morton, D., Seibert, P., Angevine, W. M., Evan, S., Dingwell, A., Fast, J. D., Easter, R. C., Pisso, I., Burkhart, J. F., and Wotawa, G.: The Lagrangian particle dispersion model FLEXPART-WRF version 3.1, Geoscientific Model Development, https://doi.org/10.5194/gmd-6-1889-2013, 2013. a, b
Brown, C. W. and Keeling, C. D.: The concentration of atmospheric carbon dioxide in Antarctica, Journal of Geophysical Research (1896-1977), 70, 6077–6085, https://doi.org/10.1029/JZ070i024p06077, 1965. a
Chambers, S. D., Podstawczyńska, A., Pawlak, W., Fortuniak, K., Williams, A. G., and Griffiths, A. D.: Characterizing the State of the Urban Surface Layer Using Radon-222, Journal of Geophysical Research, https://doi.org/10.1029/2018jd029507, 2019. a
Chambers, S. D., Griffiths, A. D., Williams, A. G., Sisoutham, O., Morosh, V., Röttger, S., Mertes, F., and Röttger, A.: Portable two-filter dual-flow-loop 222Rn detector: stand-alone monitor and calibration transfer device, Adv. Geosci., 57, 63–80, https://doi.org/10.5194/adgeo-57-63-2022, 2022. a
Colnenne-David, C., Grandeau, G., Jeuffroy, M.-H., and Doré, T.: Nitrous oxide fluxes and soil nitrogen contents over eight years in four cropping systems designed to meet both environmental and production goals: A French field nitrogen data set, Data in Brief, https://doi.org/10.1016/j.dib.2021.107303, 2021. a
Crippa, M., Guizzardi, D., Pagani, F., Banja, M., Muntean, M., Schaaf, E., Monforti-Ferrario, F., Becker, W., Quadrelli, R., Risquez Martin, A., Taghavi-Moharamli, P., Köykkä, J., Grassi, G., Rossi, S., Melo, J., Oom, D., Branco, A., San-Miguel, J., Manca, G., Pisoni, E., Vignati, E., and Pekar, F.: GHG emissions of all world countries, Tech. Rep. KJ-01-24-010-EN-N (online), KJ-01-24-010-EN-C (print), Eueropean Union, Luxembourg (Luxembourg), https://doi.org/10.2760/4002897 (online), https://doi.org/10.2760/0115360 (print), 2024. a
Fang, S. X., Zhou, L. X., Tans, P. P., Ciais, P., Steinbacher, M., Xu, L., and Luan, T.: In situ measurement of atmospheric CO2 at the four WMO/GAW stations in China, Atmos. Chem. Phys., 14, 2541–2554, https://doi.org/10.5194/acp-14-2541-2014, 2014. a
Gamage, L. P., Hix, E. G., and Gichuhi, W. K.: Ground-Based Atmospheric Measurements of CO:CO2 Ratios in Eastern Highland Rim Using a CO Tracer Technique, ACS Earth and Space Chemistry, 4, 558–571, https://doi.org/10.1021/acsearthspacechem.9b00322, 2020. a
Garnier, J., Casquin, A., Mercier, B., Martinez, A., Gréhan, E., Azougui, A., Bosc, S., Pomet, A., Billen, G., and Mary, B.: Six years of nitrous oxide emissions from temperate cropping systems under real-farm rotational management, Agricultural and Forest Meteorology, https://doi.org/10.1016/j.agrformet.2024.110085, 2024. a, b
Griffiths, A. D., Chambers, S. D., Williams, A. G., and Werczynski, S.: yIncreasing the accuracy and temporal resolution of two-filter radon–222 measurements by correcting for the instrument response, Atmos. Meas. Tech., 9, 2689–2707, https://doi.org/10.5194/amt-9-2689-2016, 2016. a
Grossi, C., Vogel, F. R., Curcoll, R., Àgueda, A., Vargas, A., Rodó, X., and Morguí, J.-A.: Study of the daily and seasonal atmospheric CH4 mixing ratio variability in a rural Spanish region using 222Rn tracer, Atmos. Chem. Phys., 18, 5847–5860, https://doi.org/10.5194/acp-18-5847-2018, 2018. a, b, c
Grossi, C., Chambers, S. D., Llido, O., Vogel, F. R., Kazan, V., Capuana, A., Werczynski, S., Curcoll, R., Delmotte, M., Vargas, A., Morguí, J.-A., Levin, I., and Ramonet, M.: Intercomparison study of atmospheric 222Rn and 222Rn progeny monitors, Atmos. Meas. Tech., 13, 2241–2255, https://doi.org/10.5194/amt-13-2241-2020, 2020. a, b
Hammer, S. and Levin, I.: Seasonal variation of the molecular hydrogen uptake by soils inferred from continuous atmospheric observations in Heidelberg, southwest Germany, Tellus B, https://doi.org/10.1111/j.1600-0889.2009.00417.x, 2009. a, b, c, d
Heiskanen, J., Brümmer, C., Buchmann, N., Calfapietra, C., Chen, H., Gielen, B., Gkritzalis, T., Hammer, S., Hartman, S. E., Herbst, M., Janssens, I. A., Jordan, A., Juurola, E., Karstens, U., Kasurinen, V., Kruijt, B., Lankreijer, H., Levin, I., Linderson, M.-L., Loustau, D., Merbold, L., Myhre, C. L., Papale, D., Pavelka, M., Pilegaard, K., Ramonet, M., Rebmann, C., Rinne, J., Rivier, L., Saltikoff, E., Saltikoff, E., Sanders, R. J., Steinbacher, M., Steinhoff, T., Watson, A. J., Vermeulen, A., Vesala, T., Vítková, G., and Kutsch, W. L.: The Integrated Carbon Observation System in Europe, Bulletin of the American Meteorological Society, https://doi.org/10.1175/bams-d-19-0364.1, 2021. a
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Kikaj, D., Chambers, S. D., Kobal, M., Crawford, J., and Vaupotič, J.: Characterizing atmospheric controls on winter urban pollution in a topographic basin setting using Radon-222, Atmospheric Research, https://doi.org/10.1016/j.atmosres.2019.104838, 2020. a
Kikaj, D., Chung, E., Griffiths, A. D., Chambers, S. D., Forster, G., Wenger, A., Pickers, P., Rennick, C., O'Doherty, S., Pitt, J., Stanley, K., Young, D., Fleming, L. S., Adcock, K., Safi, E., and Arnold, T.: Direct high-precision radon quantification for interpreting high-frequency greenhouse gas measurements, Atmos. Meas. Tech., 18, 151–175, https://doi.org/10.5194/amt-18-151-2025, 2025. a, b, c
Kuenen, J. J. P., Visschedijk, A. J. H., Jozwicka, M., and Denier van der Gon, H. A. C.: TNO-MACC_II emission inventory; a multi-year (2003–2009) consistent high-resolution European emission inventory for air quality modelling, Atmos. Chem. Phys., 14, 10963–10976, https://doi.org/10.5194/acp-14-10963-2014, 2014. a
Levin, I., Glatzel-Mattheier, H., Marik, T., Cuntz, M., Schmidt, M., and Worthy, D. E. J.: Verification of German methane emission inventories and their recent changes based on atmospheric observations, Journal of Geophysical Research, https://doi.org/10.1029/1998jd100064, 1999. a, b, c, d
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Short summary
Here, we use greenhouse gas and radon data from a tall tower in France to estimate their fluxes within the station footprint from January 2017 to October 2024 using the Radon Tracer Method. Using the latest radon exhalation maps and standardized radon measurements, we found the greenhouse gas fluxes to be in agreement with the literature. Compared to inventories, there is a general agreement except for carbon dioxide where we show that the biogenic fluxes are not well represented in the model.
Here, we use greenhouse gas and radon data from a tall tower in France to estimate their fluxes...
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