Articles | Volume 25, issue 9
https://doi.org/10.5194/acp-25-4703-2025
© 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-25-4703-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
06 May 2025
Research article |
| 06 May 2025
| 06 May 2025
Marine emissions and trade winds control the atmospheric nitrous oxide in the Galapagos Islands
Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA, USA
Dickon Young
School of Chemistry, University of Bristol, Bristol, UK
Nazaret Narváez Jimenez
Galapagos Science Center (GSC), Universidad San Francisco de Quito (USFQ) and UNC-Chapel Hill, Puerto Baquerizo Moreno, Galapagos, Ecuador
Cristina Vintimilla-Palacios
Galapagos Science Center (GSC), Universidad San Francisco de Quito (USFQ) and UNC-Chapel Hill, Puerto Baquerizo Moreno, Galapagos, Ecuador
Ariel Pila Alonso
Galapagos Science Center (GSC), Universidad San Francisco de Quito (USFQ) and UNC-Chapel Hill, Puerto Baquerizo Moreno, Galapagos, Ecuador
Paul B. Krummel
CSIRO Environment, Aspendale, Victoria, Australia
William Vizuete
Department of Environmental Sciences and Engineering, University of North Carolina, Chapel Hill, NC, USA
Department of Earth, Atmospheric and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA, USA
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Chloe A. Brashear, Maarten M. J. W. van Herpen, Sergey Gromov, Berend van de Kraats, Carina van der Veen, Xietiancheng Yu, Matthew S. Johnson, Helder Timas, Sönke Zaehle, Armin Jordan, Heiko Moossen, Africa Barreto, Natalia Pratts, Isabel Baños, Jesús Arrieta, Dickon Young, Peter Sealy, Hella van Asperen, Simonetta Montaguti, Peter Sperlich, Rowena Moss, Sylvia Nichol, Stephen Matthew Platt, Ove Hermansen, Cathrine Lund Myhre, Gabrielle Petron, Andy Crotwell, Isaac Vimont, and Thomas Röckmann
EGUsphere, https://doi.org/10.5194/egusphere-2026-5618, https://doi.org/10.5194/egusphere-2026-5618, 2026
This preprint is open for discussion and under review for Atmospheric Chemistry and Physics (ACP).
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This study evaluates trends in atmospheric CO between 1995–2025 and uses the isotopic composition of CO to constrain emission shifts during this time. We find that CO from fossil fuel combustion has reduced dramatically in the Northern Hemisphere during winter, linked to global air quality regulations. Conversely, a small background rise in CO is driven by increasing atmospheric CH4 and recent extreme wildfire seasons have caused large peaks in CO, counteracting reductions from fossil emissions.
Alexandra E. Ng, Manish Shrivastava, Brian Gaudet, Cenlin He, Zezhen Cheng, and William Vizuete
EGUsphere, https://doi.org/10.5194/egusphere-2026-5534, https://doi.org/10.5194/egusphere-2026-5534, 2026
This preprint is open for discussion and under review for Atmospheric Chemistry and Physics (ACP).
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Wildfire smoke contains dark particles called tar balls that absorb sunlight and warm the air, but air quality and climate models usually leave them out. We added tar balls to a model of the southeastern United States and compared it with aircraft and ground measurements. Including them, and accounting for the coatings that form around them, raised the sunlight absorbed by smoke by up to 6 %. Models that omit tar balls may therefore underestimate warming from wildfires.
Sara L. Farrell, Quazi Z. Rasool, Havala O. T. Pye, Yue Zhang, Ying Li, Yuzhi Chen, Chi-Tsan Wang, Haofei Zhang, Ryan Schmedding, Manabu Shiraiwa, Jaime Green, Sri H. Budisulistiorini, Jose L. Jimenez, Weiwei Hu, Jason D. Surratt, and William Vizuete
Atmos. Chem. Phys., 26, 13557–13579, https://doi.org/10.5194/acp-26-13557-2026, https://doi.org/10.5194/acp-26-13557-2026, 2026
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Fine particulate matter (PM2.5) has become increasingly important to regulate and model. In this study, we parameterize non-ideal aerosol mixing and phase state into the Community Multiscale Air Quality (CMAQ) model and analyze its impact on the formation of a globally important source of PM2.5, isoprene epoxydiol (IEPOX)-derived PM2.5. Incorporating these features furthers model bias in IEPOX-derived PM2.5, however, this work provides potential phase state bounds for future PM2.5 modeling work.
Clara M. Nussbaumer, Colette L. Heald, Teresa Campos, Eric A. Kort, Paul B. Krummel, Ray L. Langenfelds, Monica Madronich, Kathryn McKain, Gabrielle Pétron, Ann Stavert, and Steven C. Wofsy
EGUsphere, https://doi.org/10.5194/egusphere-2026-5476, https://doi.org/10.5194/egusphere-2026-5476, 2026
This preprint is open for discussion and under review for Atmospheric Chemistry and Physics (ACP).
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Changes in emissions and climate increasingly impact the remote Southern Hemisphere and we know little about the consequences for the atmospheric composition. We investigate if rapid increases in the greenhouse gas methane since 2008 have led to increases in carbon monoxide. A global model confirms this hypothesis and shows that enhanced emissions from plants and rising temperatures also contribute to the trend. Observations are inconsistent and highlight the need for more accurate measurements.
Kirstin Gerrand, Elena Fillola, Alistair J. Manning, Jgor Arduini, Paul B. Krummel, Chris R. Lunder, Jens Mühle, Simon O'Doherty, Sunyoung Park, Ronald G. Prinn, Stefan Reimann, Dickon Young, and Matthew Rigby
Atmos. Meas. Tech., 19, 5387–5400, https://doi.org/10.5194/amt-19-5387-2026, https://doi.org/10.5194/amt-19-5387-2026, 2026
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To analyse long-term trends in atmospheric trace gas concentrations, it is important to identify data points minimally affected by local pollution sources or air masses carried from other latitudes or altitudes. Traditional methods for detecting these “baselines” are computationally expensive or lack a basis in physical principles. This paper introduces a machine-learning method that uses meteorological data and offers significantly lower computational costs compared to physics-based techniques.
Alice E. Ramsden, Anita L. Ganesan, Matthew Rigby, Chris Rennick, Tim Arnold, Emmal Safi, Edward Chung, Dafina Kikaj, Cameron Yeo, Dave Lowry, Pete Levy, Simon O'Doherty, Kieran M. Stanley, Dickon Young, Joe Pitt, Damien Martin, Morgan Lopez, Michel Ramonet, Grant L. Forster, Arnoud Frumau, and Alistair J. Manning
Atmos. Chem. Phys., 26, 11421–11448, https://doi.org/10.5194/acp-26-11421-2026, https://doi.org/10.5194/acp-26-11421-2026, 2026
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Methane is emitted from a range of anthropogenic and natural sources, each with a characteristic isotope ratio signature. We present a method for estimating emissions from multiple sources using isotopic signatures and observations of atmospheric methane isotope ratios. We show the importance of considering isotopic signature uncertainty and demonstrate how our current understanding of these signatures may be limiting this method’s ability to reduce uncertainties in emissions estimates.
Kane Stone, Candice Chen, Susan Solomon, Luke M. Western, Paul B. Krummel, Gabrielle Pétron, Jens Mühle, and Simon O'Doherty
Atmos. Chem. Phys., 26, 10241–10253, https://doi.org/10.5194/acp-26-10241-2026, https://doi.org/10.5194/acp-26-10241-2026, 2026
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There is growing interest in hydrogens impact on atmospheric chemistry and climate. Here, the seasonality of hydrogen oxidation and loss to microbial activity in soils are investigated using information from the hydrofluorocarbon, HFC-152a. A large seasonal range of the soil sink, over twice that of hydroxyl loss, is seen in the Northern latitudes peaking in the late summer, while the Southern latitudes show a much lower range. This will be useful for validating model hydrogen cycles.
Joseph R. Pitt, Dominique Rust, Anita Ganesan, Luke M. Western, Martin K. Vollmer, Jens Mühle, Tobias Bühlmann, Christina M. Harth, Stephen A. Montzka, Brad D. Hall, Isaac J. Vimont, Alistair J. Manning, Alison L. Redington, Stephan Henne, Daniela B. Melo, Saurabh Annadate, Lionel Constantin, Brendan M. Murphy, Matthew Rigby, Dickon Young, Simon O'Doherty, Angelina Wenger, Chris R. Lunder, Ove Hermansen, Thomas Wagenhäuser, Andreas Engel, Jgor Arduini, Michela Maione, Jaegeun Yun, Blagoj Mitrevski, Paul B. Krummel, Paul J. Fraser, Jooil Kim, Ray H. J. Wang, Tae Siek Rhee, Peter K. Salameh, T. Gerard Spain, Stefan Reimann, Ronald G. Prinn, Ray F. Weiss, and Kieran M. Stanley
Atmos. Chem. Phys., 26, 10167–10195, https://doi.org/10.5194/acp-26-10167-2026, https://doi.org/10.5194/acp-26-10167-2026, 2026
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1,2‑Dichloroethane (DCE) can contribute to the depletion of the stratospheric ozone layer. Whether DCE reaches the stratosphere depends on where and when it is emitted. We present the ongoing measurements of DCE from the Advanced Global Atmospheric Gases Experiment (AGAGE) and National Oceanic and Atmospheric Administration (NOAA) global monitoring networks. For the period 2017–2023, our modelled average global emissions based on these observations align with another study, while regional estimates differ. This suggests remaining uncertainty in the geographical distribution of emissions.
Piers M. Forster, Tristram Walsh, Chris Smith, William F. Lamb, Robin Lamboll, Christophe Cassou, Mathias Hauser, Zeke Hausfather, June-Yi Lee, Matthew D. Palmer, Karina von Schuckmann, Aimée B. A. Slangen, Sophie Szopa, Blair Trewin, Jeongeun Yun, Nathan P. Gillett, Stuart Jenkins, H. Damon Matthews, Krishnan Raghavan, Aurélien Ribes, Joeri Rogelj, Debbie Rosen, Xuebin Zhang, Myles Allen, Robbie M. Andrew, Chris Atkinson, Richard A. Betts, Antonio Bombelli, Samantha N. Burgess, Lijing Cheng, Helen E. Claxton, Pierre Friedlingstein, Thomas L. Frölicher, Catia M. Domingues, Thomas Gasser, Catherine H. Gregory, Rachel M. Hoesly, Daniel Huppmann, Masayoshi Ishii, Christopher Kadow, Alexia Karwat, John Kennedy, Rachel E. Killick, Mahesh V. M. Kovilakam, Paul B. Krummel, Xin Lan, Jean-François Lamarque, Aurélien Liné, Belén Martín-Míguez, Didier P. Monselesan, Colin Morice, Jens Mühle, Pino Mussak, Glen P. Peters, Anna Pirani, Julia Pongratz, Matthew Rigby, Robert Rohde, Abhishek Savita, Sonia I. Seneviratne, Steven J. Smith, Ghassan Taha, Caterina Tassone, Peter Thorne, Christopher Wells, Luke M. Western, Guido R. van der Werf, Susan E. Wijffels, Marco Zecchetto, Junting Zhong, Xiao-Ye Zhang, Valérie Masson-Delmotte, and Panmao Zhai
Earth Syst. Sci. Data, 18, 3889–3933, https://doi.org/10.5194/essd-18-3889-2026, https://doi.org/10.5194/essd-18-3889-2026, 2026
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We give our annual update of key climate indicators. Our work quantifies the human contribution to global warming and the pace of climate change. This represents a large effort by the international community akin to an Intergovernmental Panel on Climate Change (IPCC) report.
Hélène De Longueville, Daniela B. Melo, Alison L. Redington, Alice Ramsden, Alexandre Danjou, Peter Andrews, Joseph Pitt, Brendan Murphy, Lionel Constantin, Kieran M. Stanley, Simon O'Doherty, Angelina Wenger, Dickon Young, Andreas Engel, Tanja Schuck, Katharina Meixner, Thomas Wagenhaeuser, Fides Gad, Martin K. Vollmer, Stefan Reimann, Michela Maoine, Jgor Arduini, Chris Lunder, Norbert Schmidtbauer, László Haszpra, Mihály Molnár, Arnoud Frumau, Cedric Couret, Matthew Rigby, Stephan Henne, Alistair Manning, and Anita L. Ganesan
Atmos. Chem. Phys., 26, 7647–7675, https://doi.org/10.5194/acp-26-7647-2026, https://doi.org/10.5194/acp-26-7647-2026, 2026
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This study estimates emissions of hydrofluorocarbons, potent greenhouse gases, in north-western Europe using atmospheric observations and atmospheric modelling. The estimates are compared with nationally reported emissions submitted to the United Nations. Overall, our results are consistent with reported values, although differences are found for some gases and countries. The findings indicate that emissions in north-western Europe are declining, reflecting the effects of climate regulations.
Emmal Safi, Joe Pitt, Grant Forster, Chris Rennick, Simon O’Doherty, Dickon Young, Kanokrat Charoenpornpukdee, Nick Garrard, Dafina Kikaj, Andrew Manning, Gerard Spain, Damien Martin, Morgan Lopez, Michel Ramonet, and Kieran Stanely
EGUsphere, https://doi.org/10.5194/egusphere-2026-1802, https://doi.org/10.5194/egusphere-2026-1802, 2026
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We compared whole and synthetic-air reference materials (RMs) for investigating offsets in greenhouse gas measurements so data from different sites/networks can be trusted when combined. By sending whole and synthetic-air (RMs) to six sites and measuring under routine field conditions, we found whole-air gives the most precise results, especially for carbon dioxide and nitrous oxide. Synthetic-air worked fairly well for methane but synthetic-air RMs needs lower uncertainty before wide use.
Martin K. Vollmer, Joseph R. Pitt, Dickon Young, Stephan Henne, Blagoj Mitrevski, Jens Mühle, Anita Ganesan, Jgor Arduini, Alistair J. Manning, Thomas Wagenhäuser, Alison L. Redington, Daniela B. Melo, Brendan Murphy, Ray Gluckmann, Kieran M. Stanley, Paul B. Krummel, Chris R. Lunder, Jaegeun Yun, Dominique Rust, Angelina Wenger, Myriam Guillevic, Jooil Kim, Ray H. J. Wang, Tae Siek Rhee, Lionel Constantin, Arnoud Frumau, Christina M. Harth, Peter K. Salameh, Ove Hermansen, Matthew Rigby, Luke M. Western, Andreas Engel, Simon O'Doherty, Sunyoung Park, Michela Maione, Paul J. Fraser, Ronald G. Prinn, Ray F. Weiss, and Stefan Reimann
Atmos. Chem. Phys., 26, 6993–7012, https://doi.org/10.5194/acp-26-6993-2026, https://doi.org/10.5194/acp-26-6993-2026, 2026
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Halogenated olefins (HFOs) are newly emerging compounds in the atmosphere. They are in reach of the definition of PFAS (Per- and polyfluoroalkyl substances) and some decay to the eternal chemical trifluoroacetate (TFA). We provide atmospheric measurements of three HFOs from the large Advanced Global Atmospheric Gases Experiment (AGAGE) network and estimate emissions for Northwest Europe for the first time. We find a quasi-ubiquitous presence in the atmosphere and rapidly increasing emissions.
Elinor C. Tuffnell, Emma Leedham-Elvidge, William T. Sturges, Harald Bönisch, Karina E. Adcock, Paul J. Fraser, Paul B. Krummel, David E. Oram, Ray L. Langenfelds, Thomas Röckmann, Luke M. Western, Jens Mühle, and Johannes C. Laube
Atmos. Chem. Phys., 26, 4583–4599, https://doi.org/10.5194/acp-26-4583-2026, https://doi.org/10.5194/acp-26-4583-2026, 2026
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The greater the stratospheric lifetime of chlorofluorocarbons (CFCs), the longer they will deplete ozone. This paper investigates four longer-lived CFCs, and discovers two of them have much shorter lifetimes than previously believed. Demonstrating emissions of these compounds are higher than assumed, to account for their abundance. Unusually this paper uses stratospheric whole-air samples, rather than models or lab-based experiments, to derive policy-relevant metrics for these compounds.
Benjamin Püschel, Martin Vojta, Luise Kandler, Molly Crotwell, Andreas Engel, Paul B. Krummel, Chris R. Lunder, Jens Mühle, Simon O'Doherty, Ronald G. Prinn, Kieran M. Stanley, Isaac Vimont, Martin K. Vollmer, Thomas Wagenhäuser, Ray F. Weiss, Dickon Young, and Andreas Stohl
EGUsphere, https://doi.org/10.5194/egusphere-2025-5656, https://doi.org/10.5194/egusphere-2025-5656, 2025
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We present global and regionally resolved emissions of the two highly potent greenhouse gases CF4 and C2F6 from 2006 to 2023, based on atmospheric measurements and transport modeling. In nearly all regions studied, our results show that national reports and industry-based data underestimate emissions. While emissions in Europe and the U.S. declined, we find rising emissions in South, Southeast, and East Asia. China and India are the major contributors to global emissions in recent years.
Luke M. Western, Stephen Bourguet, Molly Crotwell, Lei Hu, Paul B. Krummel, Hélène De Longueville, Alistair J. Manning, Jens Mühle, Dominique Rust, Isaac Vimont, Martin K. Vollmer, Minde An, Jgor Arduini, Andreas Engel, Paul J. Fraser, Anita L. Ganesan, Christina M. Harth, Chris Lunder, Michela Maione, Stephen A. Montzka, David Nance, Simon O'Doherty, Sunyoung Park, Stefan Reimann, Peter K. Salameh, Roland Schmidt, Kieran M. Stanley, Thomas Wagenhäuser, Dickon Young, Matt Rigby, Ronald G. Prinn, and Ray F. Weiss
Atmos. Chem. Phys., 25, 17761–17778, https://doi.org/10.5194/acp-25-17761-2025, https://doi.org/10.5194/acp-25-17761-2025, 2025
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We used atmospheric measurements to estimate emissions of two hydrochlorofluorocarbon (HCFC) gases, called HCFC-123 and HCFC-124, that harm the ozone layer. Despite international regulation to stop their production, their emissions have not fallen. This may be linked to how they are used to make other chemicals. Our findings show that some banned substances are still reaching the atmosphere, likely through leaks during chemical production, which could slow the recovery of the ozone layer.
Luke M. Western, Matthew Rigby, Jens Mühle, Paul B. Krummel, Chris R. Lunder, Simon O'Doherty, Stefan Reimann, Martin K. Vollmer, Dickon Young, Ben Adam, Paul J. Fraser, Anita L. Ganesan, Christina M. Harth, Ove Hermansen, Jooil Kim, Ray L. Langenfelds, Zoë M. Loh, Blagoj Mitrevski, Joseph R. Pitt, Peter K. Salameh, Roland Schmidt, Kieran Stanley, Ann R. Stavert, Hsiang-Jui Wang, Ray F. Weiss, and Ronald G. Prinn
Earth Syst. Sci. Data, 17, 6557–6582, https://doi.org/10.5194/essd-17-6557-2025, https://doi.org/10.5194/essd-17-6557-2025, 2025
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We used global measurements and an atmospheric model to estimate how emissions and abundances of 42 chemically and radiatively important trace gases have changed over time. These gases affect the Earth's radiative balance and the ozone layer. Our data sets help track progress in reducing emissions of these gases to the atmosphere. This work supports international efforts to protect the environment by providing clear, long-term, consistent data on how these gases are changing in the atmosphere.
Martin Vojta, Andreas Plach, Rona L. Thompson, Pallav Purohit, Kieran Stanley, Simon O'Doherty, Dickon Young, Joe Pitt, Jgor Arduini, Xin Lan, and Andreas Stohl
Atmos. Chem. Phys., 25, 15197–15243, https://doi.org/10.5194/acp-25-15197-2025, https://doi.org/10.5194/acp-25-15197-2025, 2025
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We determine European emissions of the highly potent greenhouse gas sulfur hexafluoride from 2005 to 2021 – focusing on high-emitting countries and the aggregated EU-27 emissions. Emissions declined in most regions, likely due to EU F-gas regulations. However, our results reveal that most studied countries underestimate their emissions in their national reports. Our sensitivity tests highlight the importance of dense observational networks for reliable inversion-based emission estimates.
Piers M. Forster, Chris Smith, Tristram Walsh, William F. Lamb, Robin Lamboll, Christophe Cassou, Mathias Hauser, Zeke Hausfather, June-Yi Lee, Matthew D. Palmer, Karina von Schuckmann, Aimée B. A. Slangen, Sophie Szopa, Blair Trewin, Jeongeun Yun, Nathan P. Gillett, Stuart Jenkins, H. Damon Matthews, Krishnan Raghavan, Aurélien Ribes, Joeri Rogelj, Debbie Rosen, Xuebin Zhang, Myles Allen, Lara Aleluia Reis, Robbie M. Andrew, Richard A. Betts, Alex Borger, Jiddu A. Broersma, Samantha N. Burgess, Lijing Cheng, Pierre Friedlingstein, Catia M. Domingues, Marco Gambarini, Thomas Gasser, Johannes Gütschow, Masayoshi Ishii, Christopher Kadow, John Kennedy, Rachel E. Killick, Paul B. Krummel, Aurélien Liné, Didier P. Monselesan, Colin Morice, Jens Mühle, Vaishali Naik, Glen P. Peters, Anna Pirani, Julia Pongratz, Jan C. Minx, Matthew Rigby, Robert Rohde, Abhishek Savita, Sonia I. Seneviratne, Peter Thorne, Christopher Wells, Luke M. Western, Guido R. van der Werf, Susan E. Wijffels, Valérie Masson-Delmotte, and Panmao Zhai
Earth Syst. Sci. Data, 17, 2641–2680, https://doi.org/10.5194/essd-17-2641-2025, https://doi.org/10.5194/essd-17-2641-2025, 2025
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In a rapidly changing climate, evidence-based decision-making benefits from up-to-date and timely information. Here we compile monitoring datasets to track real-world changes over time. To make our work relevant to policymakers, we follow methods from the Intergovernmental Panel on Climate Change (IPCC). Human activities are increasing the Earth's energy imbalance and driving faster sea-level rise compared to the IPCC assessment.
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.
Sara L. Farrell, Havala O. T. Pye, Robert Gilliam, George Pouliot, Deanna Huff, Golam Sarwar, William Vizuete, Nicole Briggs, Fengkui Duan, Tao Ma, Shuping Zhang, and Kathleen Fahey
Atmos. Chem. Phys., 25, 3287–3312, https://doi.org/10.5194/acp-25-3287-2025, https://doi.org/10.5194/acp-25-3287-2025, 2025
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In this work we implement heterogeneous sulfur chemistry into the Community Multiscale Air Quality (CMAQ) model. This new chemistry accounts for the formation of sulfate via aqueous oxidation of SO2 in aerosol liquid water and the formation of hydroxymethanesulfonate (HMS) – often confused by measurement techniques as sulfate. Model performance in predicting sulfur PM2.5 in Fairbanks, Alaska, and other places that experience dark and cold winters is improved.
Tahereh Alinejadtabrizi, Yi Huang, Francisco Lang, Steven Siems, Michael Manton, Luis Ackermann, Melita Keywood, Ruhi Humphries, Paul Krummel, Alastair Williams, and Greg Ayers
Atmos. Chem. Phys., 25, 2631–2648, https://doi.org/10.5194/acp-25-2631-2025, https://doi.org/10.5194/acp-25-2631-2025, 2025
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Clouds over the Southern Ocean are crucial to Earth's energy balance, but understanding the factors that control them is complex. Our research examines how weather patterns affect tiny particles called cloud condensation nuclei (CCN), which influence cloud properties. Using data from Kennaook / Cape Grim, we found that winter air from Antarctica brings cleaner conditions with lower CCN, while summer patterns from Australia transport more particles. Precipitation also helps reduce CCN in winter.
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.
Gabrielle Pétron, Andrew M. Crotwell, John Mund, Molly Crotwell, Thomas Mefford, Kirk Thoning, Bradley Hall, Duane Kitzis, Monica Madronich, Eric Moglia, Donald Neff, Sonja Wolter, Armin Jordan, Paul Krummel, Ray Langenfelds, and John Patterson
Atmos. Meas. Tech., 17, 4803–4823, https://doi.org/10.5194/amt-17-4803-2024, https://doi.org/10.5194/amt-17-4803-2024, 2024
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Hydrogen (H2) is a gas in trace amounts in the Earth’s atmosphere with indirect impacts on climate and air quality. Renewed interest in H2 as a low- or zero-carbon source of energy may lead to increased production, uses, and supply chain emissions. NOAA measurements of weekly air samples collected between 2009 and 2021 at over 50 sites in mostly remote locations are now available, and they complement other datasets to study the H2 global budget.
Hanqin Tian, Naiqing Pan, Rona L. Thompson, Josep G. Canadell, Parvadha Suntharalingam, Pierre Regnier, Eric A. Davidson, Michael Prather, Philippe Ciais, Marilena Muntean, Shufen Pan, Wilfried Winiwarter, Sönke Zaehle, Feng Zhou, Robert B. Jackson, Hermann W. Bange, Sarah Berthet, Zihao Bian, Daniele Bianchi, Alexander F. Bouwman, Erik T. Buitenhuis, Geoffrey Dutton, Minpeng Hu, Akihiko Ito, Atul K. Jain, Aurich Jeltsch-Thömmes, Fortunat Joos, Sian Kou-Giesbrecht, Paul B. Krummel, Xin Lan, Angela Landolfi, Ronny Lauerwald, Ya Li, Chaoqun Lu, Taylor Maavara, Manfredi Manizza, Dylan B. Millet, Jens Mühle, Prabir K. Patra, Glen P. Peters, Xiaoyu Qin, Peter Raymond, Laure Resplandy, Judith A. Rosentreter, Hao Shi, Qing Sun, Daniele Tonina, Francesco N. Tubiello, Guido R. van der Werf, Nicolas Vuichard, Junjie Wang, Kelley C. Wells, Luke M. Western, Chris Wilson, Jia Yang, Yuanzhi Yao, Yongfa You, and Qing Zhu
Earth Syst. Sci. Data, 16, 2543–2604, https://doi.org/10.5194/essd-16-2543-2024, https://doi.org/10.5194/essd-16-2543-2024, 2024
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Atmospheric concentrations of nitrous oxide (N2O), a greenhouse gas 273 times more potent than carbon dioxide, have increased by 25 % since the preindustrial period, with the highest observed growth rate in 2020 and 2021. This rapid growth rate has primarily been due to a 40 % increase in anthropogenic emissions since 1980. Observed atmospheric N2O concentrations in recent years have exceeded the worst-case climate scenario, underscoring the importance of reducing anthropogenic N2O emissions.
Piers M. Forster, Chris Smith, Tristram Walsh, William F. Lamb, Robin Lamboll, Bradley Hall, Mathias Hauser, Aurélien Ribes, Debbie Rosen, Nathan P. Gillett, Matthew D. Palmer, Joeri Rogelj, Karina von Schuckmann, Blair Trewin, Myles Allen, Robbie Andrew, Richard A. Betts, Alex Borger, Tim Boyer, Jiddu A. Broersma, Carlo Buontempo, Samantha Burgess, Chiara Cagnazzo, Lijing Cheng, Pierre Friedlingstein, Andrew Gettelman, Johannes Gütschow, Masayoshi Ishii, Stuart Jenkins, Xin Lan, Colin Morice, Jens Mühle, Christopher Kadow, John Kennedy, Rachel E. Killick, Paul B. Krummel, Jan C. Minx, Gunnar Myhre, Vaishali Naik, Glen P. Peters, Anna Pirani, Julia Pongratz, Carl-Friedrich Schleussner, Sonia I. Seneviratne, Sophie Szopa, Peter Thorne, Mahesh V. M. Kovilakam, Elisa Majamäki, Jukka-Pekka Jalkanen, Margreet van Marle, Rachel M. Hoesly, Robert Rohde, Dominik Schumacher, Guido van der Werf, Russell Vose, Kirsten Zickfeld, Xuebin Zhang, Valérie Masson-Delmotte, and Panmao Zhai
Earth Syst. Sci. Data, 16, 2625–2658, https://doi.org/10.5194/essd-16-2625-2024, https://doi.org/10.5194/essd-16-2625-2024, 2024
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This paper tracks some key indicators of global warming through time, from 1850 through to the end of 2023. It is designed to give an authoritative estimate of global warming to date and its causes. We find that in 2023, global warming reached 1.3 °C and is increasing at over 0.2 °C per decade. This is caused by all-time-high greenhouse gas emissions.
Emily Dowd, Alistair J. Manning, Bryn Orth-Lashley, Marianne Girard, James France, Rebecca E. Fisher, Dave Lowry, Mathias Lanoisellé, Joseph R. Pitt, Kieran M. Stanley, Simon O'Doherty, Dickon Young, Glen Thistlethwaite, Martyn P. Chipperfield, Emanuel Gloor, and Chris Wilson
Atmos. Meas. Tech., 17, 1599–1615, https://doi.org/10.5194/amt-17-1599-2024, https://doi.org/10.5194/amt-17-1599-2024, 2024
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We provide the first validation of the satellite-derived emission estimates using surface-based mobile greenhouse gas surveys of an active gas leak detected near Cheltenham, UK. GHGSat’s emission estimates broadly agree with the surface-based mobile survey and steps were taken to fix the leak, highlighting the importance of satellite data in identifying emissions and helping to reduce our human impact on climate change.
Rona L. Thompson, Stephen A. Montzka, Martin K. Vollmer, Jgor Arduini, Molly Crotwell, Paul B. Krummel, Chris Lunder, Jens Mühle, Simon O'Doherty, Ronald G. Prinn, Stefan Reimann, Isaac Vimont, Hsiang Wang, Ray F. Weiss, and Dickon Young
Atmos. Chem. Phys., 24, 1415–1427, https://doi.org/10.5194/acp-24-1415-2024, https://doi.org/10.5194/acp-24-1415-2024, 2024
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The hydroxyl radical determines the atmospheric lifetimes of numerous species including methane. Since OH is very short-lived, it is not possible to directly measure its concentration on scales relevant for understanding its effect on other species. Here, OH is inferred by looking at changes in hydrofluorocarbons (HFCs). We find that OH levels have been fairly stable over our study period (2004 to 2021), suggesting that OH is not the main driver of the recent increase in atmospheric methane.
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.
John D. Patterson, Murat Aydin, Andrew M. Crotwell, Gabrielle Pétron, Jeffery P. Severinghaus, Paul B. Krummel, Ray L. Langenfelds, Vasilii V. Petrenko, and Eric S. Saltzman
Clim. Past, 19, 2535–2550, https://doi.org/10.5194/cp-19-2535-2023, https://doi.org/10.5194/cp-19-2535-2023, 2023
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Atmospheric levels of molecular hydrogen (H2) can impact climate and air quality. Constraining past changes to atmospheric H2 is useful for understanding how H2 cycles through the Earth system and predicting the impacts of increasing anthropogenic emissions under the
hydrogen economy. Here, we use the aging air found in the polar snowpack to reconstruct H2 levels over the past 100 years. We find that H2 levels increased by 30 % over Greenland and 60 % over Antarctica during the 20th century.
Chi-Tsan Wang, Bok H. Baek, William Vizuete, Lawrence S. Engel, Jia Xing, Jaime Green, Marc Serre, Richard Strott, Jared Bowden, and Jung-Hun Woo
Earth Syst. Sci. Data, 15, 5261–5279, https://doi.org/10.5194/essd-15-5261-2023, https://doi.org/10.5194/essd-15-5261-2023, 2023
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Hazardous air pollutant (HAP) human exposure studies usually rely on local measurements or dispersion model methods, but those methods are limited under spatial and temporal conditions. We processed the US EPA emission data to simulate the hourly HAP emission patterns and applied the chemical transport model to simulate the HAP concentrations. The modeled HAP results exhibit good agreement (R is 0.75 and NMB is −5.6 %) with observational data.
Ioannis Katharopoulos, Dominique Rust, Martin K. Vollmer, Dominik Brunner, Stefan Reimann, Simon J. O'Doherty, Dickon Young, Kieran M. Stanley, Tanja Schuck, Jgor Arduini, Lukas Emmenegger, and Stephan Henne
Atmos. Chem. Phys., 23, 14159–14186, https://doi.org/10.5194/acp-23-14159-2023, https://doi.org/10.5194/acp-23-14159-2023, 2023
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The effectiveness of climate change mitigation needs to be scrutinized by monitoring greenhouse gas (GHG) emissions. Countries report their emissions to the UN in a bottom-up manner. By combining atmospheric observations and transport models someone can independently validate emission estimates in a top-down fashion. We report Swiss emissions of synthetic GHGs based on kilometer-scale transport and inverse modeling, highlighting the role of appropriate resolution in complex terrain.
Hyeri Park, Jooil Kim, Haklim Choi, Sohyeon Geum, Yeaseul Kim, Rona L. Thompson, Jens Mühle, Peter K. Salameh, Christina M. Harth, Kieran M. Stanley, Simon O'Doherty, Paul J. Fraser, Peter G. Simmonds, Paul B. Krummel, Ray F. Weiss, Ronald G. Prinn, and Sunyoung Park
Atmos. Chem. Phys., 23, 9401–9411, https://doi.org/10.5194/acp-23-9401-2023, https://doi.org/10.5194/acp-23-9401-2023, 2023
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Based on atmospheric HFC-23 observations, the first estimate of post-CDM HFC-23 emissions in eastern Asia for 2008–2019 shows that these emissions contribute significantly to the global emissions rise. The observation-derived emissions were much larger than the bottom-up estimates expected to approach zero after 2015 due to national abatement activities. These discrepancies could be attributed to unsuccessful factory-level HFC-23 abatement and inaccurate quantification of emission reductions.
Alison L. Redington, Alistair J. Manning, Stephan Henne, Francesco Graziosi, Luke M. Western, Jgor Arduini, Anita L. Ganesan, Christina M. Harth, Michela Maione, Jens Mühle, Simon O'Doherty, Joseph Pitt, Stefan Reimann, Matthew Rigby, Peter K. Salameh, Peter G. Simmonds, T. Gerard Spain, Kieran Stanley, Martin K. Vollmer, Ray F. Weiss, and Dickon Young
Atmos. Chem. Phys., 23, 7383–7398, https://doi.org/10.5194/acp-23-7383-2023, https://doi.org/10.5194/acp-23-7383-2023, 2023
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Chlorofluorocarbons (CFCs) were used in Europe pre-1990, damaging the stratospheric ozone layer. Legislation has controlled production and use, and global emissions have decreased sharply. The global rate of decline in CFC-11 recently slowed and was partly attributed to illegal emission in eastern China. This study concludes that emissions of CFC-11 in western Europe have not contributed to the unexplained part of the global increase in CFC-11 observed in the last decade.
John C. Tracey, Andrew R. Babbin, Elizabeth Wallace, Xin Sun, Katherine L. DuRussel, Claudia Frey, Donald E. Martocello III, Tyler Tamasi, Sergey Oleynik, and Bess B. Ward
Biogeosciences, 20, 2499–2523, https://doi.org/10.5194/bg-20-2499-2023, https://doi.org/10.5194/bg-20-2499-2023, 2023
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Nitrogen (N) is essential for life; thus, its availability plays a key role in determining marine productivity. Using incubations of seawater spiked with a rare form of N measurable on a mass spectrometer, we quantified microbial pathways that determine marine N availability. The results show that pathways that recycle N have higher rates than those that result in its loss from biomass and present new evidence for anaerobic nitrite oxidation, a process long thought to be strictly aerobic.
Angharad C. Stell, Michael Bertolacci, Andrew Zammit-Mangion, Matthew Rigby, Paul J. Fraser, Christina M. Harth, Paul B. Krummel, Xin Lan, Manfredi Manizza, Jens Mühle, Simon O'Doherty, Ronald G. Prinn, Ray F. Weiss, Dickon Young, and Anita L. Ganesan
Atmos. Chem. Phys., 22, 12945–12960, https://doi.org/10.5194/acp-22-12945-2022, https://doi.org/10.5194/acp-22-12945-2022, 2022
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Nitrous oxide is a potent greenhouse gas and ozone-depleting substance, whose atmospheric abundance has risen throughout the contemporary record. In this work, we carry out the first global hierarchical Bayesian inversion to solve for nitrous oxide emissions. We derive increasing global nitrous oxide emissions over 2011–2020, which are mainly driven by emissions between 0° and 30°N, with the highest emissions recorded in 2020.
Maria Paula Pérez-Peña, Jenny A. Fisher, Dylan B. Millet, Hisashi Yashiro, Ray L. Langenfelds, Paul B. Krummel, and Scott H. Kable
Atmos. Chem. Phys., 22, 12367–12386, https://doi.org/10.5194/acp-22-12367-2022, https://doi.org/10.5194/acp-22-12367-2022, 2022
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We used two atmospheric models to test the implications of previously unexplored aldehyde photochemistry on the atmospheric levels of molecular hydrogen (H2). We showed that the new photochemistry from aldehydes produces more H2 over densely forested areas. Compared to the rest of the world, it is over these forested regions where the produced H2 is more likely to be removed. The results highlight that other processes that contribute to atmospheric H2 levels should be studied further.
Luke M. Western, Alison L. Redington, Alistair J. Manning, Cathy M. Trudinger, Lei Hu, Stephan Henne, Xuekun Fang, Lambert J. M. Kuijpers, Christina Theodoridi, David S. Godwin, Jgor Arduini, Bronwyn Dunse, Andreas Engel, Paul J. Fraser, Christina M. Harth, Paul B. Krummel, Michela Maione, Jens Mühle, Simon O'Doherty, Hyeri Park, Sunyoung Park, Stefan Reimann, Peter K. Salameh, Daniel Say, Roland Schmidt, Tanja Schuck, Carolina Siso, Kieran M. Stanley, Isaac Vimont, Martin K. Vollmer, Dickon Young, Ronald G. Prinn, Ray F. Weiss, Stephen A. Montzka, and Matthew Rigby
Atmos. Chem. Phys., 22, 9601–9616, https://doi.org/10.5194/acp-22-9601-2022, https://doi.org/10.5194/acp-22-9601-2022, 2022
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The production of ozone-destroying gases is being phased out. Even though production of one of the main ozone-depleting gases, called HCFC-141b, has been declining for many years, the amount that is being released to the atmosphere has been increasing since 2017. We do not know for sure why this is. A possible explanation is that HCFC-141b that was used to make insulating foams many years ago is only now escaping to the atmosphere, or a large part of its production is not being reported.
Guus J. M. Velders, John S. Daniel, Stephen A. Montzka, Isaac Vimont, Matthew Rigby, Paul B. Krummel, Jens Muhle, Simon O'Doherty, Ronald G. Prinn, Ray F. Weiss, and Dickon Young
Atmos. Chem. Phys., 22, 6087–6101, https://doi.org/10.5194/acp-22-6087-2022, https://doi.org/10.5194/acp-22-6087-2022, 2022
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The emissions of hydrofluorocarbons (HFCs) have increased significantly in the past as a result of the phasing out of ozone-depleting substances. Observations indicate that HFCs are used much less in certain refrigeration applications than previously projected. Current policies are projected to reduce emissions and the surface temperature contribution of HFCs from 0.28–0.44 °C to 0.14–0.31 °C in 2100. The Kigali Amendment is projected to reduce the contributions further to 0.04 °C in 2100.
Haklim Choi, Mi-Kyung Park, Paul J. Fraser, Hyeri Park, Sohyeon Geum, Jens Mühle, Jooil Kim, Ian Porter, Peter K. Salameh, Christina M. Harth, Bronwyn L. Dunse, Paul B. Krummel, Ray F. Weiss, Simon O'Doherty, Dickon Young, and Sunyoung Park
Atmos. Chem. Phys., 22, 5157–5173, https://doi.org/10.5194/acp-22-5157-2022, https://doi.org/10.5194/acp-22-5157-2022, 2022
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We observed 12-year continuous CH3Br pollution signals at Gosan and estimated anthropogenic CH3Br emissions in eastern China. The analysis revealed a significant discrepancy between top-down estimates and the bottom-up emissions from the fumigation usage reported to the United Nations Environment Programme, likely due to unreported or inaccurately reported fumigation usage. This result provides information to monitor international compliance with the Montreal Protocol.
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.
Peter Sperlich, Gordon W. Brailsford, Rowena C. Moss, John McGregor, Ross J. Martin, Sylvia Nichol, Sara Mikaloff-Fletcher, Beata Bukosa, Magda Mandic, C. Ian Schipper, Paul Krummel, and Alan D. Griffiths
Atmos. Meas. Tech., 15, 1631–1656, https://doi.org/10.5194/amt-15-1631-2022, https://doi.org/10.5194/amt-15-1631-2022, 2022
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We tested an in situ analyser for carbon and oxygen isotopes in atmospheric CO2 at Baring Head, New Zealand’s observatory for Southern Ocean baseline air. The analyser was able to resolve regional signals of the terrestrial carbon cycle, although the analysis of small events was limited by analytical uncertainty. Further improvement of the instrument performance would be desirable for the robust analysis of distant signals and to resolve the small variability in Southern Ocean baseline air.
Jens Mühle, Lambert J. M. Kuijpers, Kieran M. Stanley, Matthew Rigby, Luke M. Western, Jooil Kim, Sunyoung Park, Christina M. Harth, Paul B. Krummel, Paul J. Fraser, Simon O'Doherty, Peter K. Salameh, Roland Schmidt, Dickon Young, Ronald G. Prinn, Ray H. J. Wang, and Ray F. Weiss
Atmos. Chem. Phys., 22, 3371–3378, https://doi.org/10.5194/acp-22-3371-2022, https://doi.org/10.5194/acp-22-3371-2022, 2022
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Emissions of the strong greenhouse gas perfluorocyclobutane (c-C4F8) into the atmosphere have been increasing sharply since the early 2000s. These c-C4F8 emissions are highly correlated with the amount of hydrochlorofluorocarbon-22 produced to synthesize polytetrafluoroethylene (known for its non-stick properties) and related chemicals. From this process, c-C4F8 by-product is vented to the atmosphere. Avoiding these unnecessary c-C4F8 emissions could reduce the climate impact of this industry.
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.
Cited articles
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Ganesan, A. L., Chatterjee, A., Prinn, R. G., Harth, C. M., Salameh, P. K., Manning, A. J., Hall, B. D., Mühle, J., Meredith, L. K., Weiss, R. F., O'Doherty, S., and Young, D.: The variability of methane, nitrous oxide and sulfur hexafluoride in Northeast India, Atmos. Chem. Phys., 13, 10633–10644, https://doi.org/10.5194/acp-13-10633-2013, 2013. a, b
Ganesan, A. L., Manning, A. J., Grant, A., Young, D., Oram, D. E., Sturges, W. T., Moncrieff, J. B., and O'Doherty, S.: Quantifying methane and nitrous oxide emissions from the UK and Ireland using a national-scale monitoring network, Atmos. Chem. Phys., 15, 6393–6406, https://doi.org/10.5194/acp-15-6393-2015, 2015. a, b
Ganesan, A. L., Manizza, M., Morgan, E. J., Harth, C. M., Kozlova, E., Lueker, T., Manning, A. J., Lunt, M. F., Mühle, J., Lavric, J. V., Heimann, M., Weiss, R. F., and Rigby, M.: Marine nitrous oxide emissions from three eastern boundary upwelling systems inferred from atmospheric observations, Geophys. Res. Lett., 47, e2020GL087822, https://doi.org/10.1029/2020GL087822, 2020. a
Grant, A., Witham, C. S., Simmonds, P. G., Manning, A. J., and O'Doherty, S.: A 15 year record of high-frequency, in situ measurements of hydrogen at Mace Head, Ireland, Atmos. Chem. Phys., 10, 1203–1214, https://doi.org/10.5194/acp-10-1203-2010, 2010. a
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Short summary
We present the initial 15 months of nitrous oxide measurements from the Galapagos Emissions Monitoring Station. The observed variability in atmospheric mole fractions during this period can be linked to several factors: seasonal variations in trade wind speed and direction across the eastern Pacific, differences in the transport history of air masses sampled, and spatiotemporal heterogeneity in regional marine nitrous oxide emissions from the coastal upwelling systems of Peru and Chile.
We present the initial 15 months of nitrous oxide measurements from the Galapagos Emissions...
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