Articles | Volume 23, issue 24
https://doi.org/10.5194/acp-23-15693-2023
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/acp-23-15693-2023
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
21 Dec 2023
Research article |
| 21 Dec 2023
| 21 Dec 2023
Fingerprints of the COVID-19 economic downturn and recovery on ozone anomalies at high-elevation sites in North America and western Europe
National Research Council of Italy – Institute of Atmospheric Sciences and Climate, CNR–ISAC, Turin, Italy
Paolo Cristofanelli
National Research Council of Italy – Institute of Atmospheric Sciences and Climate, CNR–ISAC, Bologna, Italy
Kai-Lan Chang
Cooperative Institute for Research in Environmental Sciences, University of Colorado Boulder/NOAA Chemical Sciences Laboratory, Boulder, USA
Gaëlle Dufour
Université de Paris Cité and Univ. Paris Est Créteil, CNRS, LISA, Paris, France
Gregory Beachley
Office of Atmospheric Protection, U.S. Environmental Protection Agency, Washington DC, USA
Cédric Couret
German Environment Agency, Zugspitze, Germany
Peter Effertz
Cooperative Institute for Research in Environmental Sciences, University of Colorado Boulder/NOAA Global Monitoring Laboratory, Boulder, USA
Daniel A. Jaffe
University of Washington, School of STEM/Department of Atmospheric Sciences, Bothell/Seattle, USA
Dagmar Kubistin
Hohenpeißenberg Meteorological Observatory, Deutscher Wetterdienst, Hohenpeißenberg, Germany
Jason Lynch
Office of Atmospheric Protection, U.S. Environmental Protection Agency, Washington DC, USA
Irina Petropavlovskikh
Cooperative Institute for Research in Environmental Sciences, University of Colorado Boulder/NOAA Global Monitoring Laboratory, Boulder, USA
Melissa Puchalski
Office of Atmospheric Protection, U.S. Environmental Protection Agency, Washington DC, USA
Timothy Sharac
Office of Atmospheric Protection, U.S. Environmental Protection Agency, Washington DC, USA
Barkley C. Sive
Air Resources Division, National Park Service, Denver, USA
Martin Steinbacher
Empa, Laboratory for Air Pollution & Environmental Technology, Dübendorf, Switzerland
Carlos Torres
Izaña Atmospheric Research Center, State Meteorological Agency of Spain, IARC-AEMET, Tenerife, Spain
Owen R. Cooper
Cooperative Institute for Research in Environmental Sciences, University of Colorado Boulder/NOAA Chemical Sciences Laboratory, Boulder, USA
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We compared six years of carbon dioxide and methane measurements from two nearby laboratories at the high mountain station on Mount Cimone, Italy. Both recorded similar long-term and seasonal changes, but hourly readings often differed beyond limits recommended by WMO. Sampling location, data selection and moisture removal contributed to these differences; human presence may also have played a role. Standardization of sampling and procedures can make greenhouse gas measurements more consistent.
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The iberulite fall was, to our knowledge, the first reported in central Europe. What was special was that the fall was observed in situ and that the meteorological conditions during the fall are well known. The meteorology and the particle size distribution inside the iberulites strongly corroborate below-cloud scavenging as a probable formation mechanism. The discovery of further iberulites Saharan dust event (SDE) samples collected since suggests that iberulites are common but overlooked by other researchers.
Cuiqi Zhang, Xiaoli Shen, Justin Jacquot, Larissa Lacher, Selvakumar Vishnupriya, Benjamin T. Brem, Robin L. Modini, Nora Nowak, Michael Sprenger, Martin Steinbacher, Stephan Henne, Martine Collaud Coen, Franz Conen, Kristina Höhler, Ottmar Möhler, Martin Gysel-Beer, Daniel J. Cziczo, and Zamin A. Kanji
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This preprint is open for discussion and under review for Atmospheric Chemistry and Physics (ACP).
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Clouds play a key role in weather and climate, but the particles that trigger cloud ice formation are difficult to identify directly. By simulating clouds in a cloud chamber and particle measurements at a mountain station, we found that mineral dust was the main trigger of cloud ice formation. Dust from local construction and transported from higher atmospheric layers both contributed. The study shows that both human activities and atmospheric processes can influence cloud formation.
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This preprint is open for discussion and under review for Atmospheric Measurement Techniques (AMT).
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Xiaoyi Zhao, Vitali Fioletov, Irina Petropavlovskikh, Voltaire Velazco, Alberto Redondas, Anna Solomatnikova, Corinne Vigouroux, Kimberly Strong, Michel Van Roozendael, Andrea Pazmino, Thomas F. Hanisco, Alexander Cede, Martin Tiefengraber, Gordon Labow, Masatomo Fujiwara, Ronald van der A, Debora Griffin, Chris McLinden, Tom Kralidis, Wolfgang Steinbrecht, and Sum Chi Lee
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Joël Thanwerdas, Paolo Cristofanelli, Angela Fiore, Rianne Dröge, Sophie Van Mil, Yohanna Villalobos, Zhendong Wu, and Dominik Brunner
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Louis Mirallie, Eliane Maillard Barras, Caroline Jonas, Corinne Vigouroux, Roeland Van Malderen, Irina Petropavlovskikh, Sophie Godin-Beekmann, Thierry Leblanc, Wolfgang Steinbrecht, Antoine Vadès, Rolf Ruefenacht, Alexander Haefele, Gunter Stober, Peter Effertz, Julian Gröbner, Gerard Ancellet, María Cazorla, Petra Duff, Matthias M. Frey, Michael Gill, James W. Hannigan, Nicholas Jones, Rigel Kivi, Raphael Köhler, Bogumil Kois, Debra E. Kollonige, Emmanuel Mahieu, Glen McConville, Johan Mellqvist, Gary Morris, Isao Murata, Tomoo Nagahama, Gerald E. Nedoluha, Shin-Ya Ogino, Richard Querel, Ryan M. Stauffer, Wolfgang Stremme, Kimberly Strong, Ralf Sussmann, Anne M. Thompson, and Yana Virolainen
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Julian Weng, Yufang Hao, Benjamin T. Brem, Tianqu Cui, Peeyush Khare, Lubna Dada, Kaspar R. Daellenbach, Sophie Darfeuil, Gaëlle Uzu, Jean-Luc Jaffrezo, Martin Steinbacher, Stefan Reimann, Thaleia Gkraikou, Konstantina Oikonomou, Jean Sciare, Martine Collaud Coen, Claudia Mohr, Andre S. H. Prévôt, Martin Gysel-Beer, Imad El Haddad, and Patrik Winiger
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Martina Mazzini, Diego Aliaga, Janne Lamphilati, Martin Gysel-Beer, Benjamin Tobias Brem, Robin Lewis Modini, Dominic Heslin-Rees, Tareq Hussein, Marco Zanatta, Paolo Cristofanelli, Federico Bianchi, Markku Kulmala, and Angela Marinoni
Atmos. Chem. Phys., 26, 8893–8912, https://doi.org/10.5194/acp-26-8893-2026, https://doi.org/10.5194/acp-26-8893-2026, 2026
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Irina Petropavlovskikh, Martine De Mazière, Anne M. Thompson, Jeannette D. Wild, James W. Hannigan, Henry B. Selkirk, Reem A. Hannun, Wolfgang Steinbrecht, Jean-Christopher Lambert, Roeland Van Malderen, Elizabeth Asher, Raul R. Cordero, Sophie Godin-Beekmann, Daan Hubert, Sergey Khaykin, Karin Kreher, Thierry Leblanc, Emmanuel Mahieu, Eliane Maillard Barras, Glen McConville, Gerald Nedoluha, Ivan Ortega, Alberto Redondas Marrero, Gunther Seckmeyer, Ryan M. Stauffer, Sarah A. Strode, Kim Strong, Takafumi Sugita, Michel Van Roozendael, Voltaire Velazco, Corinne Vigouroux, and Bärbel Vogel
Atmos. Chem. Phys., 26, 8637–8675, https://doi.org/10.5194/acp-26-8637-2026, https://doi.org/10.5194/acp-26-8637-2026, 2026
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This introduction to the special issue "Achievements and perspectives of the Network for the Detection of Atmospheric Composition Change after 35 years of operation” provides an overview of important research findings achieved under the NDACC objectives. The future of NDACC is discussed in the light of the evolution of the scientific questions, evolving collaborations with partners and Cooperating Networks, and the current landscape of gaps in satellite and ground-based observations.
Wenche Aas, Thérèse Salameh, Robert Wegener, Heidi Hellén, Jean-Luc Jaffrezo, Pontus Roldin, Elisabeth Alonso-Blanco, Andres Alastuey, Crist Amelynck, Jgor Arduini, Benjamin Bergmans, Marie Bertrand, Agnes Borbon, Efstratios Bourtsoukidis, Laetitia Bouvier, David Butterfield, Iris Buxbaum, Darius Ceburnis, Anja Claude, Augustin Colette, Aurélie Colomb, Sophie Darfeuil, James Dernie, Maximilien Desservettaz, Elías Díaz-Ramiro, Marvin Dufresne, René Dubus, Mario Duval, Marie Dury, Anna Font, Kirsten N. Fossum, Evelyn Freney, Gotzon Gangoiti, Yao Ge, Maria Carmen Gomez, Francisco J. Gómez-Moreno, Marie Gohy, Valérie Gros, Paul Hamer, Bryan Hellack, Hartmut Herrmann, Robert Holla, Adéla Holubová, Niels R. Jensen, Tuija Jokinen, Matthew Jones, Uwe Käfer, Lukas Kesper, Dieter Klemp, Dagmar Kubistin, Angela Marinoni, Martina Mazzini, Vy Ngoc Thuy Dinh, Jurgita Ovadnevaite, Tuukka Petäjä, Miguel Portillo-Estrada, Jitka Přívozníková, Jean-Philippe Putaud, Stefan Reimann, Laura Renzi, Veronique Riffault, Stuart Ritchie, Chris Robins, Begoña Artíñano Rodríguez de Torres, Laurent Poulain, Julian Rüdiger, Agnieszka Sanocka, Estibaliz Saez de Camara Oleaga, Niels Schoon, Roger Seco, Ivan Simmons, Leïla Simon, David Simpson, Sverre Solberg, Emmanuel Tison, August Thomasson, Svetlana Tsyro, Marsailidh Twigg, Toni Tykkä, Bert Verreyken, Ågot Watne, Katie Williams, Ana Maria Yáñez-Serrano, Karen Yeung, Ilona Ylivinkka, and Karl Espen Yttri
Atmos. Chem. Phys., 26, 8717–8751, https://doi.org/10.5194/acp-26-8717-2026, https://doi.org/10.5194/acp-26-8717-2026, 2026
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A one-week intensive measurement campaign during the 2022 European heatwave included monitoring of ozone, volatile organic compounds, aerosol chemical composition, and organic tracers to investigate air pollution sources. Results showed that emissions from vegetation and human activities contributed to peaks in ozone and secondary organic aerosol particles. Differences between measurements and model simulations underline the need for better characterization of sources and formation pathways.
Caroline Jonas, Corinne Vigouroux, Bavo Langerock, Robin Björklund, Anne Boynard, Thomas Carlund, Martine De Mazière, Peter Effertz, Quentin Errera, Matthias M. Frey, José Granville, James W. Hannigan, Arno Keppens, Nis Jepsen, Rigel Kivi, Norrie Lyall, Mathias Palm, Maxime Prignon, Viktoria F. Sofieva, Kimberly Strong, Tove Svendby, David Tarasick, Laura Thölix, Roeland Van Malderen, Yana Virolainen, Sibylle von Löwis, and Xiaoyi Zhao
Atmos. Chem. Phys., 26, 8089–8124, https://doi.org/10.5194/acp-26-8089-2026, https://doi.org/10.5194/acp-26-8089-2026, 2026
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We study the evolution of ozone in the Arctic over the 2000–2024 period in the stratosphere (about 10 to 50 km) to assess the expected recovery of the ozone layer following the diminution of ozone-depleting substances. We merge ground-based data sets within spatially coherent regions to reduce uncertainties and we obtain positive trends for the total column everywhere in the Arctic and for the middle and upper stratosphere over Canada, but no significant trends in the lower stratosphere.
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.
Paul D. Hamer, Miha Markelj, Oscar Rojas-Munoz, Bertrand Bonan, Jean-Christophe Calvet, Virginie Marécal, Alex Guenther, Heidi Trimmel, Islen Vallejo, Sabine Eckhardt, Gabriela Sousa Santos, Katerina Sindelarova, David Simpson, Norbert Schmidbauer, Heidi Hellén, Pascal Rubli, Stefan Reimann, Anja Claude, Dagmar Kubistin, Julie Cozic, James Dernie, and Leonor Tarrasón
Earth Syst. Sci. Data, 18, 3635–3669, https://doi.org/10.5194/essd-18-3635-2026, https://doi.org/10.5194/essd-18-3635-2026, 2026
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Plants release gases like isoprene that can form ozone and affect air quality. Using models and satellite data, we mapped the emissions of isoprene from plants across Europe and found that droughts can reduce leaf growth, leading to lower emissions. This shows that to understand and predict air quality, we must also understand how drought impacts vegetation. Our findings highlight the value of linking extreme weather, plant health, and pollution in models of the Earth system as a whole.
Liang Feng, Paul I. Palmer, Haolin Wang, Robert Parker, Hartmut Boesch, Sébastien C. Biraud, Łukasz Chmura, Emanuel Gloor, László Haszpra, Elena Kozlova, Euan G. Nisbet, Steffen M. Noe, Thomas Röckmann, Rodrigo Augusto Ferreira de Souza, and Martin Steinbacher
EGUsphere, https://doi.org/10.5194/egusphere-2026-2662, https://doi.org/10.5194/egusphere-2026-2662, 2026
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This study examines the relative roles of emissions and oxidation in recent rapid methane growth. Using an ensemble Kalman filter, we quantify global methane sources and sinks for 2018–2024. Emission changes dominate the increase, except in 2020 when a COVID‑19‑related OH decline strongly affected sinks. Atmospheric photochemistry—including OH and CH₄ variability and temperature‑dependent oxidation—also significantly shapes the methane budget.
Viktoria F. Sofieva, Monika E. Szelag, Natalya A. Kramarova, Robert Damadeo, Wolfgang Steinbrecht, Irina Petropavlovskikh, Corinne Vigouroux, Eliane Maillard Barras, Daniel Zawada, Kleareti Tourpali, Stacey M. Frith, Jeannette D. Wild, Sean M. Davis, Carlo Arosio, Mark Weber, Alexei Rozanov, Brian Auffarth, Lucien Froidevaux, Ryan Fuller, Doug Degenstein, Kimberlee Dube, Peter Effertz, Thierry Leblanc, Gérard Ancellet, Sophie Godin-Beekmann, Glen McConville, Richard Querel, Dan Smale, Marie-Renee DeBacker, Emmanuel Mahieu, and Ralf Sussmann
Atmos. Chem. Phys., 26, 7387–7405, https://doi.org/10.5194/acp-26-7387-2026, https://doi.org/10.5194/acp-26-7387-2026, 2026
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We present an updated evaluation of stratospheric ozone profile trends in the 60°S–60°N latitude range using long-term ground-based and satellite climate data records, as well as simulations by chemistry-climate models. Analyses confirm the statistically significant positive ozone trends in the upper stratosphere of ~1–3 % decade-1. The trends are close to zero in the middle stratosphere, and mostly negative in the lower stratosphere, but they are not statistically significant.
Leonie Bernet, Benjamin T. Brem, Nicolas Bukowiecki, Stephan Henne, Jörg Klausen, Mathew Mutuku, David Njiru, Patricia Nying'uro, Christoph Zellweger, and Martin Steinbacher
Atmos. Chem. Phys., 26, 6741–6762, https://doi.org/10.5194/acp-26-6741-2026, https://doi.org/10.5194/acp-26-6741-2026, 2026
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Long-term atmospheric measurements are crucial to understanding climate change but remain scarce across Africa. We monitored atmospheric species at Mt. Kenya from 2020 to 2024. Our data reveal equatorial seasonal and daily variability and show that models miss local patterns. Emissions at Mt. Kenya mainly come from households, industry, and agriculture, though with large uncertainties. These findings stress the need for more ground stations to improve climate models and emission estimates.
Pauline Nibert, Yi Wu, Muriel Joly, Pierre Amato, Paolo Cristofanelli, Francescopiero Calzolari, Jean-Luc Piro, Davide Putero, Simonetta Montaguti, Laura Renzi, Franziska Vogel, Marco Rapuano, Marcello Brigante, Christophe Verhaege, Jean-Luc Baray, Laurent Deguillaume, Angela Marinoni, Marco Zanatta, and Angelica Bianco
Atmos. Chem. Phys., 26, 6489–6506, https://doi.org/10.5194/acp-26-6489-2026, https://doi.org/10.5194/acp-26-6489-2026, 2026
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This study provides the first chemical and microbiological characterization of cloud samples collected at Mt. Cimone (acronym CMN in ACTRIS, ICOS and GAW) in the Mediterranean basin. The chemical characterization is deeply discussed in relationship with back-trajectories and cloud processing. Air mass history do not fully explain the variability observed in the chemical composition. This highlights the complexity of emission sources, multiphasique exchanges, and transformations in clouds.
Rosa D. García, África Barreto, Victoria E. Cachorro, Pablo González-Sicilia, Sergio Léon-Luis, Ayoze Álvarez-Hernández, Juan José Bustos, Ramón Ramos, Fernando Almansa, Óscar Álvarez-Losada, Yenny González, Pedro Pablo Rivas, and Carlos Javier Torres
Atmos. Meas. Tech., 19, 3151–3167, https://doi.org/10.5194/amt-19-3151-2026, https://doi.org/10.5194/amt-19-3151-2026, 2026
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This study presents a unique near-source observational analysis of the spectral radiative effects of extreme biomass-burning aerosols during the August 2023 wildfire on Tenerife (Canary Islands, Spain). The exceptional proximity of the wildfire to the Izaña Observatory (2400 m a.s.l.) enabled a rare characterisation of aerosol optical properties, spectral solar irradiance, and surface radiative forcing under free-tropospheric conditions.
Marco Zanatta, Paolo Bonasoni, Francescopiero Calzolari, Paolo Cristofanelli, Sabine Eckhardt, Nikolaos Evangeliou, Cecilia Magnani, Camilla Perfetti, Davide Putero, Laura Renzi, Franziska Vogel, and Angela Marinoni
Earth Syst. Sci. Data Discuss., https://doi.org/10.5194/essd-2026-211, https://doi.org/10.5194/essd-2026-211, 2026
Revised manuscript under review for ESSD
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This work presents 18 years of high-quality observations of equivalent black carbon concentration measured at the Monte Cimone mountain site in Italy. We provide a detailed description of the measurement setup, data processing, and associated uncertainties to ensure consistency over time. The openly available dataset offers information for long-term studies, including the integration of renaltysis data parameters and comparison with atmospheric models.
Shuang Fu, Xuemei Qing, Kunpeng Zang, Yi Lin, Shuo Liu, Yuanyuan Chen, Bingjiang Chen, Wei Gao, Martin Steinbacher, and Shuangxi Fang
Atmos. Chem. Phys., 26, 5477–5496, https://doi.org/10.5194/acp-26-5477-2026, https://doi.org/10.5194/acp-26-5477-2026, 2026
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Urban carbon dynamics are critical for climate action, yet remote background monitoring often misses key details. This study utilized the unique vantage point of the 632-m Shanghai Tower to investigate carbon dioxide and carbon monoxide dynamics directly above the urban core. Our research confirms such elevated observations can effectively track metropolitan-scale footprint, revealing fossil fuels as the dominant source (85%) of excess carbon dioxide and supporting targeted reduction measures.
Sachiko Okamoto, Juan Cuesta, Gaëlle Dufour, Maxim Eremenko, Kazuyuki Miyazaki, Cathy Boonne, Hiroshi Tanimoto, Jeff Peischl, and Chelsea Thompson
Atmos. Chem. Phys., 26, 4685–4709, https://doi.org/10.5194/acp-26-4685-2026, https://doi.org/10.5194/acp-26-4685-2026, 2026
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We analyse the distribution of tropospheric ozone over the Atlantic during February and October 2017 using a multispectral satellite synergism called IASI+GOME2, two chemistry reanalysis products and in situ airborne measurements. It reveals that a significant overestimation of two chemistry reanalysis products of lowermost troposphere ozone over the Atlantic in the Northern Hemisphere due to the overestimations of ozone precursors from anthropogenic sources from North America.
Enrico Mancinelli, Saurabh Annadate, Paolo Cristofanelli, Umberto Giostra, Michela Maione, Stefan Reimann, and Jgor Arduini
Atmos. Chem. Phys., 26, 4105–4129, https://doi.org/10.5194/acp-26-4105-2026, https://doi.org/10.5194/acp-26-4105-2026, 2026
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Propane is the second most abundant non-methane hydrocarbon in the atmosphere and is mainly emitted by anthropogenic activities. Despite playing a significant role in atmospheric chemistry, propane emission sources are poorly defined. Analysis of high-frequency long-term measurements at the GAW-WMO (Global Atmosphere Watch-World Meteorological Organization) station of Monte Cimone Italy make some improvements in identifications of different contributions at the regional scale.
Martine Collaud Coen, Benjamin Tobias Brem, Martin Gysel-Beer, Robin Modini, Stephan Henne, Martin Steinbacher, Davide Putero, Maria I. Gini, and Kostantinos Eleftheriadis
Atmos. Chem. Phys., 26, 1623–1645, https://doi.org/10.5194/acp-26-1623-2026, https://doi.org/10.5194/acp-26-1623-2026, 2026
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Saharan dust (SD) is transported over long distances by large-scale atmospheric circulation, reaching the Jungfraujoch high-altitude station 30 to 150 times per year. This study analyses the influence of instrument types on the SD detection using the single scattering albedo spectral dependence. This optical method is then compared to those based on size distribution and back-trajectories. The 23-year climatology of dust frequency and mass as well as the source sensitivity are also examined.
Arno Keppens, Daan Hubert, José Granville, Oindrila Nath, Jean-Christopher Lambert, Catherine Wespes, Pierre-François Coheur, Cathy Clerbaux, Anne Boynard, Richard Siddans, Barry Latter, Brian Kerridge, Serena Di Pede, Pepijn Veefkind, Juan Cuesta, Gaelle Dufour, Klaus-Peter Heue, Melanie Coldewey-Egbers, Diego Loyola, Andrea Orfanoz-Cheuquelaf, Swathi Maratt Satheesan, Kai-Uwe Eichmann, Alexei Rozanov, Viktoria F. Sofieva, Jerald R. Ziemke, Antje Inness, Roeland Van Malderen, and Lars Hoffmann
Atmos. Meas. Tech., 18, 6893–6916, https://doi.org/10.5194/amt-18-6893-2025, https://doi.org/10.5194/amt-18-6893-2025, 2025
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The first Tropospheric Ozone Assessment Report (TOAR) encountered discrepancies between several satellite sensors’ estimates of the distribution and change of ozone in the free troposphere. Therefore, contributing to the second TOAR, we harmonise as much as possible the observational perspective of sixteen tropospheric ozone products from satellites. This only partially accounts for the observed discrepancies, with a reduction of 10–40 % of the inter-product dispersion upon harmonisation.
Sebastian H. M. Hickman, Makoto M. Kelp, Paul T. Griffiths, Kelsey Doerksen, Kazuyuki Miyazaki, Elyse A. Pennington, Gerbrand Koren, Fernando Iglesias-Suarez, Martin G. Schultz, Kai-Lan Chang, Owen R. Cooper, Alex Archibald, Roberto Sommariva, David Carlson, Hantao Wang, J. Jason West, and Zhenze Liu
Geosci. Model Dev., 18, 8777–8800, https://doi.org/10.5194/gmd-18-8777-2025, https://doi.org/10.5194/gmd-18-8777-2025, 2025
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Machine learning is being more widely used across environmental and climate science. This work reviews the use of machine learning in tropospheric ozone research, focusing on three main application areas in which significant progress has been made. Common challenges in using machine learning across the three areas are highlighted, and future directions for the field are indicated.
Maksym Gachkivskyi, Ute Karstens, Bernd Fischer, Dagmar Kubistin, Jennifer Müller-Williams, Matthias Lindauer, and Ingeborg Levin
Earth Syst. Sci. Data, 17, 6173–6197, https://doi.org/10.5194/essd-17-6173-2025, https://doi.org/10.5194/essd-17-6173-2025, 2025
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222Radon (Rn) can be used to distinguish marine and continental air masses or to validate transport models. The Heidelberg Radon Monitor (HRM) measures 214polonium (Po), a progeny of Rn. This study presents Po-based Rn activity concentrations measured with the HRM at eight stations in Germany with guidelines for estimating Rn from Po measurements. Comparison between modeled and measured activity concentrations shows that at high relative humidity Po measurements cannot be interpreted as Rn.
Sina Voshtani, Dylan B. A. Jones, Debra Wunch, Drew C. Pendergrass, Paul O. Wennberg, David F. Pollard, Isamu Morino, Hirofumi Ohyama, Nicholas M. Deutscher, Frank Hase, Ralf Sussmann, Damien Weidmann, Rigel Kivi, Omaira García, Yao Té, Jack Chen, Kerry Anderson, Robin Stevens, Shobha Kondragunta, Aihua Zhu, Douglas Worthy, Senen Racki, Kathryn McKain, Maria V. Makarova, Nicholas Jones, Emmanuel Mahieu, Andrea Cadena-Caicedo, Paolo Cristofanelli, Casper Labuschagne, Elena Kozlova, Thomas Seitz, Martin Steinbacher, Reza Mahdi, and Isao Murata
Atmos. Chem. Phys., 25, 15527–15565, https://doi.org/10.5194/acp-25-15527-2025, https://doi.org/10.5194/acp-25-15527-2025, 2025
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We assess the complementarity of the greater temporal coverage provided by ground-based remote sensing data with the spatial coverage of satellite observations when these data are used together to quantify CO emissions from extreme wildfires in 2023. Our results reveal that the commonly used biomass burning emission inventories significantly underestimate the fire emissions and emphasize the importance of the ground-based remote sensing data in reducing uncertainties in the estimated emissions.
Franziska Vogel, Davide Putero, Paolo Bonasoni, Paolo Cristofanelli, Marco Zanatta, and Angela Marinoni
Atmos. Chem. Phys., 25, 15453–15468, https://doi.org/10.5194/acp-25-15453-2025, https://doi.org/10.5194/acp-25-15453-2025, 2025
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Dust is in terms of mass the most abundant aerosol in the atmosphere. It can have a significant influence on e.g. the scattering and absorption of light, cloud formation, and solar energy production. We present 21 years of optical particle size distribution measurements at a mountain station in Italy, from which we assess Saharan dust transport events. A peak in the number of events was observed in summer and autumn, while a trend in the number of events over the 21 years was not detected.
Yu Yan Cui, Ju-Mee Ryoo, Matthew S. Johnson, Kai-Lan Chang, Emma L. Yates, Owen R. Cooper, and Laura T. Iraci
Earth Syst. Sci. Data, 17, 5903–5914, https://doi.org/10.5194/essd-17-5903-2025, https://doi.org/10.5194/essd-17-5903-2025, 2025
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Atmospheric observations show that free tropospheric ozone has increased across the Northern Hemisphere over the past three decades. The sources driving this increase remain unclear. In this study, we developed a source-receptor relationship database combining multiplatform ozone data and advanced atmospheric transport modeling. This database can identify emission regions responsible for ozone increases and can also be used to analyze other co-observed atmospheric constituents.
Noémie Taquet, Thomas Boulesteix, Omaira García, Robin Campion, Wolfgang Stremme, Sergio Rodríguez, Jessica López-Darias, Carlos Marrero, Diego González-García, Andreas Klügel, Frank Hase, M. Isabel García, Ramón Ramos, Pedro Rivas-Soriano, Sergio Léon-Luis, Virgilio Carreño, Antonio Alcántara, Eliezer Sépulveda, Celia Milford, Pablo González-Sicilia, and Carlos Torres
Atmos. Chem. Phys., 25, 14591–14628, https://doi.org/10.5194/acp-25-14591-2025, https://doi.org/10.5194/acp-25-14591-2025, 2025
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Volcanic gas emissions were quantified during the 2021 La Palma eruption using ground-based direct-sun Fourier transform infrared spectroscopy and differential optical absorption spectroscopy up to 140 km from the vent. New petrological estimations are consistent with our emission budgets. These findings highlight the feasibility of using existing atmospheric monitoring networks to study the atmospheric impact of volcanic degassing and support monitoring during eruptive crises.
Yuri Brugnara, Martin Steinbacher, Simone Baffelli, and Lukas Emmenegger
Atmos. Chem. Phys., 25, 14221–14236, https://doi.org/10.5194/acp-25-14221-2025, https://doi.org/10.5194/acp-25-14221-2025, 2025
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GAW-QC (Global Atmosphere Watch-Quality Control) is an interactive dashboard for the quality control of in-situ atmospheric composition measurements made at stations taking part in the Global Atmosphere Watch network. Even though it is mainly targeted at station operators who want to analyze recent, not yet published measurements, it allows anybody to verify the quality of already published measurements using various anomaly detection algorithms as well as visual comparisons.
Liang Feng, Paul I. Palmer, Luke Smallman, Jingfeng Xiao, Paolo Cristofanelli, Ove Hermansen, John Lee, Casper Labuschagne, Simonetta Montaguti, Steffen M. Noe, Stephen M. Platt, Xinrong Ren, Martin Steinbacher, and Irène Xueref-Remy
Atmos. Chem. Phys., 25, 13053–13076, https://doi.org/10.5194/acp-25-13053-2025, https://doi.org/10.5194/acp-25-13053-2025, 2025
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The year 2023 saw unexpectedly large global atmospheric CO2 growth. Satellite data reveal a role for increased tropical emissions. Larger emissions over eastern Brazil can be explained by warmer temperatures, which has led to exceptional drought, while hydrological changes play more of a role in emission increases elsewhere in the tropics. Broadly, we find that this situation continues into 2024.
Gaëlle Dufour, Maxim Eremenko, Juan Cuesta, Gérard Ancellet, Michael Gill, Eliane Maillard Barras, and Roeland Van Malderen
Atmos. Meas. Tech., 18, 5049–5070, https://doi.org/10.5194/amt-18-5049-2025, https://doi.org/10.5194/amt-18-5049-2025, 2025
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Tropospheric ozone from the three Infrared Atmospheric Sounding Interferometer (IASI) instruments is very consistent (<1 %). The validation against homogenized ozone sondes reveals an overall good agreement with slight biases (3 %–6 %) in tropospheric ozone and a possible temporal drift, but this is difficult to assess due to the limited number of sites. No specific trends are estimated for the tropospheric ozone column for the period 2008–2022, but persistent negative trends are observed in the lower troposphere.
Roeland Van Malderen, Zhou Zang, Kai-Lan Chang, Robin Björklund, Owen R. Cooper, Jane Liu, Eliane Maillard Barras, Corinne Vigouroux, Irina Petropavlovskikh, Thierry Leblanc, Valérie Thouret, Pawel Wolff, Peter Effertz, Audrey Gaudel, David W. Tarasick, Herman G. J. Smit, Anne M. Thompson, Ryan M. Stauffer, Debra E. Kollonige, Deniz Poyraz, Gérard Ancellet, Marie-Renée De Backer, Matthias M. Frey, James W. Hannigan, José L. Hernandez, Bryan J. Johnson, Nicholas Jones, Rigel Kivi, Emmanuel Mahieu, Isamu Morino, Glen McConville, Katrin Müller, Isao Murata, Justus Notholt, Ankie Piters, Maxime Prignon, Richard Querel, Vincenzo Rizi, Dan Smale, Wolfgang Steinbrecht, Kimberly Strong, and Ralf Sussmann
Atmos. Chem. Phys., 25, 9905–9935, https://doi.org/10.5194/acp-25-9905-2025, https://doi.org/10.5194/acp-25-9905-2025, 2025
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Tropospheric ozone is an important greenhouse gas and an air pollutant whose distribution and time variability are mainly governed by anthropogenic emissions and dynamics. In this paper, we assess regional trends of tropospheric ozone column amounts, based on two different approaches of merging or synthesizing ground-based observations and their trends within specific regions. Our findings clearly demonstrate regional trend differences but also consistently higher pre-COVID than post-COVID trends.
Rodrigo J. Seguel, Charlie Opazo, Yann Cohen, Owen R. Cooper, Laura Gallardo, Björn-Martin Sinnhuber, Florian Obersteiner, Andreas Zahn, Peter Hoor, Susanne Rohs, and Andreas Marsing
Atmos. Chem. Phys., 25, 8553–8573, https://doi.org/10.5194/acp-25-8553-2025, https://doi.org/10.5194/acp-25-8553-2025, 2025
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We explored ozone differences between the Northern Hemisphere and Southern Hemispheres in the upper troposphere–lower stratosphere. We found lower ozone (with stratospheric origin) in the Southern Hemisphere, especially during years of severe ozone depletion. Sudden stratospheric warming events increased the ozone in each hemisphere, highlighting the relationship between stratospheric processes and ozone in the upper troposphere, where ozone is an important greenhouse gas.
Wanmin Gong, Stephen R. Beagley, Kenjiro Toyota, Henrik Skov, Jesper Heile Christensen, Alex Lupu, Diane Pendlebury, Junhua Zhang, Ulas Im, Yugo Kanaya, Alfonso Saiz-Lopez, Roberto Sommariva, Peter Effertz, John W. Halfacre, Nis Jepsen, Rigel Kivi, Theodore K. Koenig, Katrin Müller, Claus Nordstrøm, Irina Petropavlovskikh, Paul B. Shepson, William R. Simpson, Sverre Solberg, Ralf M. Staebler, David W. Tarasick, Roeland Van Malderen, and Mika Vestenius
Atmos. Chem. Phys., 25, 8355–8405, https://doi.org/10.5194/acp-25-8355-2025, https://doi.org/10.5194/acp-25-8355-2025, 2025
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This study showed that the springtime O3 depletion plays a critical role in driving the surface O3 seasonal cycle in the central Arctic. The O3 depletion events, while occurring most notably within the lowest few hundred metres above the Arctic Ocean, can induce a 5–7 % loss in the pan-Arctic tropospheric O3 burden during springtime. The study also found enhancements in O3 and NOy (mostly peroxyacetyl nitrate) concentrations in the Arctic due to northern boreal wildfires, particularly at higher altitudes.
Rimal Abeed, Audrey Fortems-Cheiney, Grégoire Broquet, Robin Plauchu, Isabelle Pison, Antoine Berchet, Elise Potier, Bo Zheng, Gaëlle Dufour, Adriana Coman, Dilek Savas, Guillaume Siour, Henk Eskes, Beatriz Revilla-Romero, Antony Delavois, and Philippe Ciais
EGUsphere, https://doi.org/10.5194/egusphere-2025-3329, https://doi.org/10.5194/egusphere-2025-3329, 2025
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We investigate changes in air pollution from nitrogen oxides NOx (=NO+NO2) across Eastern China from 2019 to 2021, using a satellite-based modelling approach. Our results show a drop in pollution in 2020 in most provinces, and along the China-Mongolia-Russia Economic Corridor. The analysis also captures emission variations during the Lunar New Year. By estimating emissions at the provincial level, the study provides insights into how major events and policy measures influence local air quality.
Roeland Van Malderen, Anne M. Thompson, Debra E. Kollonige, Ryan M. Stauffer, Herman G. J. Smit, Eliane Maillard Barras, Corinne Vigouroux, Irina Petropavlovskikh, Thierry Leblanc, Valérie Thouret, Pawel Wolff, Peter Effertz, David W. Tarasick, Deniz Poyraz, Gérard Ancellet, Marie-Renée De Backer, Stéphanie Evan, Victoria Flood, Matthias M. Frey, James W. Hannigan, José L. Hernandez, Marco Iarlori, Bryan J. Johnson, Nicholas Jones, Rigel Kivi, Emmanuel Mahieu, Glen McConville, Katrin Müller, Tomoo Nagahama, Justus Notholt, Ankie Piters, Natalia Prats, Richard Querel, Dan Smale, Wolfgang Steinbrecht, Kimberly Strong, and Ralf Sussmann
Atmos. Chem. Phys., 25, 7187–7225, https://doi.org/10.5194/acp-25-7187-2025, https://doi.org/10.5194/acp-25-7187-2025, 2025
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Tropospheric ozone is an important greenhouse gas and is an air pollutant. The time variability of tropospheric ozone is mainly driven by anthropogenic emissions. In this paper, we study the distribution and time variability of ozone from harmonized ground-based observations from five different measurement techniques. Our findings provide clear standard references for atmospheric models and evolving tropospheric ozone satellite data for the 2000–2022 period.
Audrey Fortems-Cheiney, Grégoire Broquet, Elise Potier, Antoine Berchet, Isabelle Pison, Adrien Martinez, Robin Plauchu, Rimal Abeed, Aurélien Sicsik-Paré, Gaelle Dufour, Adriana Coman, Dilek Savas, Guillaume Siour, Henk Eskes, Hugo A. C. Denier van der Gon, and Stijn N. C. Dellaert
Atmos. Chem. Phys., 25, 6047–6068, https://doi.org/10.5194/acp-25-6047-2025, https://doi.org/10.5194/acp-25-6047-2025, 2025
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This study assesses the potential of the Ozone Monitoring Instrument (OMI) and the TROPOspheric Monitoring Instrument (TROPOMI) satellite observations to inform about the decrease in anthropogenic emissions of nitrogen oxides (NOx) in 2019 compared with 2005 at regional to national scales in Europe. Both the OMI and TROPOMI inversions show decreases in European NOx anthropogenic emission budgets in 2019 compared to 2005 but with different magnitudes.
Lubna Dada, Benjamin T. Brem, Lidia-Marta Amarandi-Netedu, Martine Collaud Coen, Nikolaos Evangeliou, Christoph Hueglin, Nora Nowak, Robin Modini, Martin Steinbacher, and Martin Gysel-Beer
Aerosol Research, 3, 315–336, https://doi.org/10.5194/ar-3-315-2025, https://doi.org/10.5194/ar-3-315-2025, 2025
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We investigated the sources of ultrafine particles (UFPs) in Payerne, Switzerland, highlighting the significant role of secondary processes in elevating UFP concentrations to levels comparable to urban areas. As the first study in rural midland Switzerland to analyze new particle formation events and secondary contributions, it offers key insights for air quality regulation and the role of agriculture in Switzerland and central Europe.
Kai-Lan Chang, Brian C. McDonald, Colin Harkins, and Owen R. Cooper
Atmos. Chem. Phys., 25, 5101–5132, https://doi.org/10.5194/acp-25-5101-2025, https://doi.org/10.5194/acp-25-5101-2025, 2025
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Exposure to high levels of ozone can be harmful to human health. This study shows consistent and robust evidence of decreasing ozone extremes across much of the United States over the period from 1990 to 2023, previously attributed to ozone precursor emission controls. Nevertheless, we also show that the increasing heat wave frequencies are likely to contribute to additional ozone exceedances, slowing the progress of decreasing the frequency of ozone exceedances.
Yenny González, María F. Sánchez-Barrero, Ioana Popovici, África Barreto, Stephane Victori, Ellsworth J. Welton, Rosa D. García, Pablo G. Sicilia, Fernando A. Almansa, Carlos Torres, and Philippe Goloub
Atmos. Meas. Tech., 18, 1885–1908, https://doi.org/10.5194/amt-18-1885-2025, https://doi.org/10.5194/amt-18-1885-2025, 2025
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We characterize the optical properties of various aerosols using a compact dual-wavelength depolarization lidar (CIMEL CE376) at 532 and 808 nm. Through a modified two-wavelength Klett inversion method, we assess the vertical distribution and temporal evolution of Saharan dust, volcanic aerosols and wildfire smoke in the subtropical North Atlantic from August 2021 to August 2023. The study confirms the CE376 lidar's effectiveness in monitoring and characterizing atmospheric aerosols over time.
Paul A. Makar, Philip Cheung, Christian Hogrefe, Ayodeji Akingunola, Ummugulsum Alyuz, Jesse O. Bash, Michael D. Bell, Roberto Bellasio, Roberto Bianconi, Tim Butler, Hazel Cathcart, Olivia E. Clifton, Alma Hodzic, Ioannis Kioutsioukis, Richard Kranenburg, Aurelia Lupascu, Jason A. Lynch, Kester Momoh, Juan L. Perez-Camanyo, Jonathan Pleim, Young-Hee Ryu, Roberto San Jose, Donna Schwede, Thomas Scheuschner, Mark W. Shephard, Ranjeet S. Sokhi, and Stefano Galmarini
Atmos. Chem. Phys., 25, 3049–3107, https://doi.org/10.5194/acp-25-3049-2025, https://doi.org/10.5194/acp-25-3049-2025, 2025
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The large range of sulfur and nitrogen deposition estimates from air quality models results in a large range of predicted impacts. We used models and deposition diagnostics to identify the processes controlling atmospheric sulfur and nitrogen deposition variability. Controlling factors included the uptake of gases and aerosols by hydrometeors, aerosol inorganic chemistry, particle dry deposition, ammonia bidirectional fluxes, gas deposition via plant cuticles and soil, and land use data.
Irina Petropavlovskikh, Jeannette D. Wild, Kari Abromitis, Peter Effertz, Koji Miyagawa, Lawrence E. Flynn, Eliane Maillard Barras, Robert Damadeo, Glen McConville, Bryan Johnson, Patrick Cullis, Sophie Godin-Beekmann, Gerard Ancellet, Richard Querel, Roeland Van Malderen, and Daniel Zawada
Atmos. Chem. Phys., 25, 2895–2936, https://doi.org/10.5194/acp-25-2895-2025, https://doi.org/10.5194/acp-25-2895-2025, 2025
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Observational records show that stratospheric ozone is recovering in accordance with the implementation of the Montreal Protocol and its amendments. Natural ozone variability complicates the detection of small trends. This study optimizes a statistical model fit in ground-station-based observational records by adding parameters that interpret seasonal and long-term changes in atmospheric circulation and airmass mixing, which reduces uncertainties in detecting the stratospheric ozone recovery.
Robin Björklund, Corinne Vigouroux, Peter Effertz, Omaira E. García, Alex Geddes, James Hannigan, Koji Miyagawa, Michael Kotkamp, Bavo Langerock, Gerald Nedoluha, Ivan Ortega, Irina Petropavlovskikh, Deniz Poyraz, Richard Querel, John Robinson, Hisako Shiona, Dan Smale, Penny Smale, Roeland Van Malderen, and Martine De Mazière
Atmos. Meas. Tech., 17, 6819–6849, https://doi.org/10.5194/amt-17-6819-2024, https://doi.org/10.5194/amt-17-6819-2024, 2024
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Different ground-based ozone measurements from the last 2 decades at Lauder are compared to each other. We want to know why different trends have been observed in the stratosphere. Also, the quality and relevance of tropospheric datasets need to be evaluated. While remaining drifts are still present, our study explains roughly half of the differences in observed trends in previous studies and shows the necessity for continuous review and improvement of the measurements.
Dene Bowdalo, Sara Basart, Marc Guevara, Oriol Jorba, Carlos Pérez García-Pando, Monica Jaimes Palomera, Olivia Rivera Hernandez, Melissa Puchalski, David Gay, Jörg Klausen, Sergio Moreno, Stoyka Netcheva, and Oksana Tarasova
Earth Syst. Sci. Data, 16, 4417–4495, https://doi.org/10.5194/essd-16-4417-2024, https://doi.org/10.5194/essd-16-4417-2024, 2024
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GHOST (Globally Harmonised Observations in Space and Time) represents one of the biggest collections of harmonised measurements of atmospheric composition at the surface. In total, 7 275 148 646 measurements from 1970 to 2023, from 227 different components, and from 38 reporting networks are compiled, parsed, and standardised. Components processed include gaseous species, total and speciated particulate matter, and aerosol optical properties.
Jia Sun, Markus Hermann, Kay Weinhold, Maik Merkel, Wolfram Birmili, Yifan Yang, Thomas Tuch, Harald Flentje, Björn Briel, Ludwig Ries, Cedric Couret, Michael Elsasser, Ralf Sohmer, Klaus Wirtz, Frank Meinhardt, Maik Schütze, Olaf Bath, Bryan Hellack, Veli-Matti Kerminen, Markku Kulmala, Nan Ma, and Alfred Wiedensohler
Atmos. Chem. Phys., 24, 10667–10687, https://doi.org/10.5194/acp-24-10667-2024, https://doi.org/10.5194/acp-24-10667-2024, 2024
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We investigated the characteristics of new particle formation (NPF) for various environments from urban background to high Alpine and the impacts of NPF on cloud condensation nuclei and aerosol radiative forcing. NPF features differ between site categories, implying the crucial role of local environmental factors such as the degree of emissions and meteorological conditions. The results also underscore the importance of local environments when assessing the impact of NPF on climate in models.
Audrey Gaudel, Ilann Bourgeois, Meng Li, Kai-Lan Chang, Jerald Ziemke, Bastien Sauvage, Ryan M. Stauffer, Anne M. Thompson, Debra E. Kollonige, Nadia Smith, Daan Hubert, Arno Keppens, Juan Cuesta, Klaus-Peter Heue, Pepijn Veefkind, Kenneth Aikin, Jeff Peischl, Chelsea R. Thompson, Thomas B. Ryerson, Gregory J. Frost, Brian C. McDonald, and Owen R. Cooper
Atmos. Chem. Phys., 24, 9975–10000, https://doi.org/10.5194/acp-24-9975-2024, https://doi.org/10.5194/acp-24-9975-2024, 2024
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The study examines tropical tropospheric ozone changes. In situ data from 1994–2019 display increased ozone, notably over India, Southeast Asia, and Malaysia and Indonesia. Sparse in situ data limit trend detection for the 15-year period. In situ and satellite data, with limited sampling, struggle to consistently detect trends. Continuous observations are vital over the tropical Pacific Ocean, Indian Ocean, western Africa, and South Asia for accurate ozone trend estimation in these regions.
Andrew O. Langford, Raul J. Alvarez II, Kenneth C. Aikin, Sunil Baidar, W. Alan Brewer, Steven S. Brown, Matthew M. Coggan, Patrick D. Cullis, Jessica Gilman, Georgios I. Gkatzelis, Detlev Helmig, Bryan J. Johnson, K. Emma Knowland, Rajesh Kumar, Aaron D. Lamplugh, Audra McClure-Begley, Brandi J. McCarty, Ann M. Middlebrook, Gabriele Pfister, Jeff Peischl, Irina Petropavlovskikh, Pamela S. Rickley, Andrew W. Rollins, Scott P. Sandberg, Christoph J. Senff, and Carsten Warneke
EGUsphere, https://doi.org/10.5194/egusphere-2024-1938, https://doi.org/10.5194/egusphere-2024-1938, 2024
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High ozone (O3) formed by reactions of nitrogen oxides (NOx) and volatile organic compounds (VOCs) can harm human health and welfare. High O3 is usually associated with hot summer days, but under certain conditions, high O3 can also form under winter conditions. In this study, we describe a high O3 event that occurred in Colorado during the COVID-19 quarantine that was caused in part by the decrease in traffic, and in part by a shallow inversion created by descent of stratospheric air.
Robin Plauchu, Audrey Fortems-Cheiney, Grégoire Broquet, Isabelle Pison, Antoine Berchet, Elise Potier, Gaëlle Dufour, Adriana Coman, Dilek Savas, Guillaume Siour, and Henk Eskes
Atmos. Chem. Phys., 24, 8139–8163, https://doi.org/10.5194/acp-24-8139-2024, https://doi.org/10.5194/acp-24-8139-2024, 2024
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This study uses the Community Inversion Framework and CHIMERE model to assess the potential of TROPOMI-S5P PAL NO2 tropospheric column data to estimate NOx emissions in France (2019–2021). Results show a 3 % decrease in average emissions compared to the 2016 CAMS-REG/INS, lower than the 14 % decrease from CITEPA. The study highlights challenges in capturing emission anomalies due to limited data coverage and error levels but shows promise for local inventory improvements.
Luis F. Millán, Peter Hoor, Michaela I. Hegglin, Gloria L. Manney, Harald Boenisch, Paul Jeffery, Daniel Kunkel, Irina Petropavlovskikh, Hao Ye, Thierry Leblanc, and Kaley Walker
Atmos. Chem. Phys., 24, 7927–7959, https://doi.org/10.5194/acp-24-7927-2024, https://doi.org/10.5194/acp-24-7927-2024, 2024
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In the Observed Composition Trends And Variability in the UTLS (OCTAV-UTLS) Stratosphere-troposphere Processes And their Role in Climate (SPARC) activity, we have mapped multiplatform ozone datasets into coordinate systems to systematically evaluate the influence of these coordinates on binned climatological variability. This effort unifies the work of studies that focused on individual coordinate system variability. Our goal was to create the most comprehensive assessment of this topic.
Kai-Lan Chang, Owen R. Cooper, Audrey Gaudel, Irina Petropavlovskikh, Peter Effertz, Gary Morris, and Brian C. McDonald
Atmos. Chem. Phys., 24, 6197–6218, https://doi.org/10.5194/acp-24-6197-2024, https://doi.org/10.5194/acp-24-6197-2024, 2024
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A great majority of observational trend studies of free tropospheric ozone use sparsely sampled ozonesonde and aircraft measurements as reference data sets. A ubiquitous assumption is that trends are accurate and reliable so long as long-term records are available. We show that sampling bias due to sparse samples can persistently reduce the trend accuracy, and we highlight the importance of maintaining adequate frequency and continuity of observations.
Xin Yang, Kimberly Strong, Alison S. Criscitiello, Marta Santos-Garcia, Kristof Bognar, Xiaoyi Zhao, Pierre Fogal, Kaley A. Walker, Sara M. Morris, and Peter Effertz
Atmos. Chem. Phys., 24, 5863–5886, https://doi.org/10.5194/acp-24-5863-2024, https://doi.org/10.5194/acp-24-5863-2024, 2024
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This study uses snow samples collected from a Canadian high Arctic site, Eureka, to demonstrate that surface snow in early spring is a net sink of atmospheric bromine and nitrogen. Surface snow bromide and nitrate are significantly correlated, indicating the oxidation of reactive nitrogen is accelerated by reactive bromine. In addition, we show evidence that snow photochemical release of reactive bromine is very weak, and its emission flux is much smaller than the deposition flux of bromide.
Meng Li, Junichi Kurokawa, Qiang Zhang, Jung-Hun Woo, Tazuko Morikawa, Satoru Chatani, Zifeng Lu, Yu Song, Guannan Geng, Hanwen Hu, Jinseok Kim, Owen R. Cooper, and Brian C. McDonald
Atmos. Chem. Phys., 24, 3925–3952, https://doi.org/10.5194/acp-24-3925-2024, https://doi.org/10.5194/acp-24-3925-2024, 2024
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In this work, we developed MIXv2, a mosaic Asian emission inventory for 2010–2017. With high spatial (0.1°) and monthly temporal resolution, MIXv2 integrates anthropogenic and open biomass burning emissions across seven sectors following a mosaic methodology. It provides CO2 emissions data alongside nine key pollutants and three chemical mechanisms. Our publicly accessible gridded monthly emissions data can facilitate long-term atmospheric and climate model analyses.
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.
Leonard Kirago, Örjan Gustafsson, Samuel Mwaniki Gaita, Sophie L. Haslett, Michael J. Gatari, Maria Elena Popa, Thomas Röckmann, Christoph Zellweger, Martin Steinbacher, Jörg Klausen, Christian Félix, David Njiru, and August Andersson
Atmos. Chem. Phys., 23, 14349–14357, https://doi.org/10.5194/acp-23-14349-2023, https://doi.org/10.5194/acp-23-14349-2023, 2023
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This study provides ground-observational evidence that supports earlier suggestions that savanna fires are the main emitters and modulators of carbon monoxide gas in Africa. Using isotope-based techniques, the study has shown that about two-thirds of this gas is emitted from savanna fires, while for urban areas, in this case Nairobi, primary sources approach 100 %. The latter has implications for air quality policy, suggesting primary emissions such as traffic should be targeted.
Rui Wang, Da Pan, Xuehui Guo, Kang Sun, Lieven Clarisse, Martin Van Damme, Pierre-François Coheur, Cathy Clerbaux, Melissa Puchalski, and Mark A. Zondlo
Atmos. Chem. Phys., 23, 13217–13234, https://doi.org/10.5194/acp-23-13217-2023, https://doi.org/10.5194/acp-23-13217-2023, 2023
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Ammonia (NH3) is a key precursor for fine particulate matter (PM2.5) and a primary form of reactive nitrogen, yet it has sparse ground measurements. We perform the first comprehensive comparison between ground observations and satellite retrievals in the US, demonstrating that satellite NH3 data can help fill spatial gaps in the current ground monitoring networks. Trend analyses using both datasets highlight increasing NH3 trends across the US, including the NH3 hotspots and urban areas.
Vitali Fioletov, Xiaoyi Zhao, Ihab Abboud, Michael Brohart, Akira Ogyu, Reno Sit, Sum Chi Lee, Irina Petropavlovskikh, Koji Miyagawa, Bryan J. Johnson, Patrick Cullis, John Booth, Glen McConville, and C. Thomas McElroy
Atmos. Chem. Phys., 23, 12731–12751, https://doi.org/10.5194/acp-23-12731-2023, https://doi.org/10.5194/acp-23-12731-2023, 2023
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Stratospheric ozone within the Southern Hemisphere springtime polar vortex has been a subject of intense research since the discovery of the Antarctic ozone hole. The wintertime ozone in the vortex is less studied. We show that the recent wintertime ozone values over the South Pole were about 12 % below the pre-1980s level; i.e., the decline there was nearly twice as large as that over southern midlatitudes. Thus, wintertime ozone there can be used as an indicator of the ozone layer state.
Thomas Trickl, Cédric Couret, Ludwig Ries, and Hannes Vogelmann
Atmos. Chem. Phys., 23, 8403–8427, https://doi.org/10.5194/acp-23-8403-2023, https://doi.org/10.5194/acp-23-8403-2023, 2023
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Downward atmospheric transport from the stratosphere (STT) is the most important natural source of tropospheric ozone. We analyse the stratospheric influence on the long-term series of ozone and carbon monoxide measured on the Zugspitze in the Bavarian Alps (2962 m a.s.l.). Since the 1970s, there has been a pronounced ozone rise that has been ascribed to an increase in STT. We determine the stratospheric influence from the observational data alone (humidity and 7Be).
Sachiko Okamoto, Juan Cuesta, Matthias Beekmann, Gaëlle Dufour, Maxim Eremenko, Kazuyuki Miyazaki, Cathy Boonne, Hiroshi Tanimoto, and Hajime Akimoto
Atmos. Chem. Phys., 23, 7399–7423, https://doi.org/10.5194/acp-23-7399-2023, https://doi.org/10.5194/acp-23-7399-2023, 2023
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We present a detailed analysis of the daily evolution of the lowermost tropospheric ozone documented by IASI+GOME2 multispectral satellite observations and that of its precursors from TCR-2 tropospheric chemistry reanalysis. It reveals that the ozone outbreak across Europe in July 2017 was produced during favorable condition for photochemical production of ozone and was associated with multiple sources of ozone precursors: biogenic, anthropogenic, and biomass burning emissions.
Luis F. Millán, Gloria L. Manney, Harald Boenisch, Michaela I. Hegglin, Peter Hoor, Daniel Kunkel, Thierry Leblanc, Irina Petropavlovskikh, Kaley Walker, Krzysztof Wargan, and Andreas Zahn
Atmos. Meas. Tech., 16, 2957–2988, https://doi.org/10.5194/amt-16-2957-2023, https://doi.org/10.5194/amt-16-2957-2023, 2023
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The determination of atmospheric composition trends in the upper troposphere and lower stratosphere (UTLS) is still highly uncertain. We present the creation of dynamical diagnostics to map several ozone datasets (ozonesondes, lidars, aircraft, and satellite measurements) in geophysically based coordinate systems. The diagnostics can also be used to analyze other greenhouse gases relevant to surface climate and UTLS chemistry.
Lixu Jin, Wade Permar, Vanessa Selimovic, Damien Ketcherside, Robert J. Yokelson, Rebecca S. Hornbrook, Eric C. Apel, I-Ting Ku, Jeffrey L. Collett Jr., Amy P. Sullivan, Daniel A. Jaffe, Jeffrey R. Pierce, Alan Fried, Matthew M. Coggon, Georgios I. Gkatzelis, Carsten Warneke, Emily V. Fischer, and Lu Hu
Atmos. Chem. Phys., 23, 5969–5991, https://doi.org/10.5194/acp-23-5969-2023, https://doi.org/10.5194/acp-23-5969-2023, 2023
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Air quality in the USA has been improving since 1970 due to anthropogenic emission reduction. Those gains have been partly offset by increased wildfire pollution in the western USA in the past 20 years. Still, we do not understand wildfire emissions well due to limited measurements. Here, we used a global transport model to evaluate and constrain current knowledge of wildfire emissions with recent observational constraints, showing the underestimation of wildfire emissions in the western USA.
Antje Hoheisel, Cedric Couret, Bryan Hellack, and Martina Schmidt
Atmos. Meas. Tech., 16, 2399–2413, https://doi.org/10.5194/amt-16-2399-2023, https://doi.org/10.5194/amt-16-2399-2023, 2023
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High-precision CO2, CH4 and CO measurements have been carried out at Zugspitze for decades. New technologies make it possible to analyse these gases with high temporal resolution. This allows the detection of local pollution. To this end, measurements have been performed on the mountain ridge (ZGR) and are compared to routine measurements at the Schneefernerhaus (ZSF). Careful manual flagging of pollution events in the ZSF data leads to consistency with the little influenced ZGR time series.
Daniel A. Jaffe, Colleen Miller, Katie Thompson, Brandon Finley, Manna Nelson, James Ouimette, and Elisabeth Andrews
Atmos. Meas. Tech., 16, 1311–1322, https://doi.org/10.5194/amt-16-1311-2023, https://doi.org/10.5194/amt-16-1311-2023, 2023
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PurpleAir sensors (PASs) are low-cost tools to measure fine particulate matter (PM) concentrations. However, the raw PAS data have significant biases, so the sensors must be corrected. We analyzed data from numerous sites and found that the standard correction to the PAS Purple Air data is accurate in urban pollution events and smoke events but leads to a 6-fold underestimate in the PM2.5 concentrations in dust events. We propose a new correction algorithm to address this problem.
Bryan J. Johnson, Patrick Cullis, John Booth, Irina Petropavlovskikh, Glen McConville, Birgit Hassler, Gary A. Morris, Chance Sterling, and Samuel Oltmans
Atmos. Chem. Phys., 23, 3133–3146, https://doi.org/10.5194/acp-23-3133-2023, https://doi.org/10.5194/acp-23-3133-2023, 2023
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In 1986, soon after the discovery of the Antarctic ozone hole, NOAA began year-round ozonesonde observations at South Pole Station to measure vertical profiles of ozone and temperature from the surface to 35 km. Balloon-borne ozonesondes launched at this unique site allow for tracking all phases of the yearly springtime ozone hole beginning in late winter and after sunrise, when rapid ozone depletion begins over the South Pole throughout the month of September.
John T. Walker, Xi Chen, Zhiyong Wu, Donna Schwede, Ryan Daly, Aleksandra Djurkovic, A. Christopher Oishi, Eric Edgerton, Jesse Bash, Jennifer Knoepp, Melissa Puchalski, John Iiames, and Chelcy F. Miniat
Biogeosciences, 20, 971–995, https://doi.org/10.5194/bg-20-971-2023, https://doi.org/10.5194/bg-20-971-2023, 2023
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Better estimates of atmospheric nitrogen (N) deposition are needed to accurately assess ecosystem risk and impacts from deposition of nutrients and acidity. Using measurements and modeling, we estimate total N deposition of 6.7 kg N ha−1 yr−1 at a forest site in the southern Appalachian Mountains, a region sensitive to atmospheric deposition. Reductions in deposition of reduced forms of N (ammonia and ammonium) will be needed to meet the lowest estimates of N critical loads for the region.
Nathaniel W. May, Noah Bernays, Ryan Farley, Qi Zhang, and Daniel A. Jaffe
Atmos. Chem. Phys., 23, 2747–2764, https://doi.org/10.5194/acp-23-2747-2023, https://doi.org/10.5194/acp-23-2747-2023, 2023
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In summer 2019 at Mt. Bachelor Observatory, we observed smoke from wildfires with transport times ranging from less than a day up to 2 weeks. Aerosol absorption of multi-day transported smoke was dominated by black carbon, while smoke with shorter transport times had greater brown carbon absorption. Notably, Siberian smoke exhibited aerosol scattering and physical properties indicative of contributions from larger particles than typically observed in smoke.
Cynthia H. Whaley, Kathy S. Law, Jens Liengaard Hjorth, Henrik Skov, Stephen R. Arnold, Joakim Langner, Jakob Boyd Pernov, Garance Bergeron, Ilann Bourgeois, Jesper H. Christensen, Rong-You Chien, Makoto Deushi, Xinyi Dong, Peter Effertz, Gregory Faluvegi, Mark Flanner, Joshua S. Fu, Michael Gauss, Greg Huey, Ulas Im, Rigel Kivi, Louis Marelle, Tatsuo Onishi, Naga Oshima, Irina Petropavlovskikh, Jeff Peischl, David A. Plummer, Luca Pozzoli, Jean-Christophe Raut, Tom Ryerson, Ragnhild Skeie, Sverre Solberg, Manu A. Thomas, Chelsea Thompson, Kostas Tsigaridis, Svetlana Tsyro, Steven T. Turnock, Knut von Salzen, and David W. Tarasick
Atmos. Chem. Phys., 23, 637–661, https://doi.org/10.5194/acp-23-637-2023, https://doi.org/10.5194/acp-23-637-2023, 2023
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This study summarizes recent research on ozone in the Arctic, a sensitive and rapidly warming region. We find that the seasonal cycles of near-surface atmospheric ozone are variable depending on whether they are near the coast, inland, or at high altitude. Several global model simulations were evaluated, and we found that because models lack some of the ozone chemistry that is important for the coastal Arctic locations, they do not accurately simulate ozone there.
Eliane Maillard Barras, Alexander Haefele, René Stübi, Achille Jouberton, Herbert Schill, Irina Petropavlovskikh, Koji Miyagawa, Martin Stanek, and Lucien Froidevaux
Atmos. Chem. Phys., 22, 14283–14302, https://doi.org/10.5194/acp-22-14283-2022, https://doi.org/10.5194/acp-22-14283-2022, 2022
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Intercomparisons of three Dobson and three Brewer spectrophotometers at Arosa/Davos, Switzerland, are used for the homogenization of the longest Umkehr ozone profiles time series worldwide. Dynamic linear modeling (DLM) reveals a significant positive trend after 2004 in the upper stratosphere, a persistent negative trend between 25 and 30 km in the middle stratosphere, and a negative trend at 20 km in the lower stratosphere, with different levels of significance depending on the dataset.
Haolin Wang, Xiao Lu, Daniel J. Jacob, Owen R. Cooper, Kai-Lan Chang, Ke Li, Meng Gao, Yiming Liu, Bosi Sheng, Kai Wu, Tongwen Wu, Jie Zhang, Bastien Sauvage, Philippe Nédélec, Romain Blot, and Shaojia Fan
Atmos. Chem. Phys., 22, 13753–13782, https://doi.org/10.5194/acp-22-13753-2022, https://doi.org/10.5194/acp-22-13753-2022, 2022
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We report significant global tropospheric ozone increases in 1995–2017 based on extensive aircraft and ozonesonde observations. Using GEOS-Chem (Goddard Earth Observing System chemistry model) multi-decadal global simulations, we find that changes in global anthropogenic emissions, in particular the rapid increases in aircraft emissions, contribute significantly to the increases in tropospheric ozone and resulting radiative impact.
Xin Yang, Kimberly Strong, Alison S. Criscitiello, Marta Santos-Garcia, Kristof Bognar, Xiaoyi Zhao, Pierre Fogal, Kaley A. Walker, Sara M. Morris, and Peter Effertz
EGUsphere, https://doi.org/10.5194/egusphere-2022-696, https://doi.org/10.5194/egusphere-2022-696, 2022
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Snow pack in high Arctic plays a key role in polar atmospheric chemistry, especially in spring when photochemistry becomes active. By sampling surface snow from a Canadian high Arctic location at Eureka, Nunavut (80° N, 86° W), we demonstrate that surface snow is a net sink rather than a source of atmospheric reactive bromine and nitrate. This finding is new and opposite to previous conclusions that snowpack is a large and direct source of reactive bromine in polar spring.
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.
Kostas Eleftheratos, John Kapsomenakis, Ilias Fountoulakis, Christos S. Zerefos, Patrick Jöckel, Martin Dameris, Alkiviadis F. Bais, Germar Bernhard, Dimitra Kouklaki, Kleareti Tourpali, Scott Stierle, J. Ben Liley, Colette Brogniez, Frédérique Auriol, Henri Diémoz, Stana Simic, Irina Petropavlovskikh, Kaisa Lakkala, and Kostas Douvis
Atmos. Chem. Phys., 22, 12827–12855, https://doi.org/10.5194/acp-22-12827-2022, https://doi.org/10.5194/acp-22-12827-2022, 2022
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We present the future evolution of DNA-active ultraviolet (UV) radiation in view of increasing greenhouse gases (GHGs) and decreasing ozone depleting substances (ODSs). It is shown that DNA-active UV radiation might increase after 2050 between 50° N–50° S due to GHG-induced reductions in clouds and ozone, something that is likely not to happen at high latitudes, where DNA-active UV radiation will continue its downward trend mainly due to stratospheric ozone recovery from the reduction in ODSs.
Daniel A. Jaffe, Brendan Schnieder, and Daniel Inouye
Atmos. Chem. Phys., 22, 12695–12704, https://doi.org/10.5194/acp-22-12695-2022, https://doi.org/10.5194/acp-22-12695-2022, 2022
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In this paper we use commonly measured pollutants (PM2.5 and carbon monoxide) to develop a Monte Carlo simulation of the mixing of urban pollution with smoke. The simulations compare well with observations from a heavily impacted smoke site and show that we can use standard regulatory measurements to quantify the amount of smoke in urban areas.
Sophie Godin-Beekmann, Niramson Azouz, Viktoria F. Sofieva, Daan Hubert, Irina Petropavlovskikh, Peter Effertz, Gérard Ancellet, Doug A. Degenstein, Daniel Zawada, Lucien Froidevaux, Stacey Frith, Jeannette Wild, Sean Davis, Wolfgang Steinbrecht, Thierry Leblanc, Richard Querel, Kleareti Tourpali, Robert Damadeo, Eliane Maillard Barras, René Stübi, Corinne Vigouroux, Carlo Arosio, Gerald Nedoluha, Ian Boyd, Roeland Van Malderen, Emmanuel Mahieu, Dan Smale, and Ralf Sussmann
Atmos. Chem. Phys., 22, 11657–11673, https://doi.org/10.5194/acp-22-11657-2022, https://doi.org/10.5194/acp-22-11657-2022, 2022
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An updated evaluation up to 2020 of stratospheric ozone profile long-term trends at extrapolar latitudes based on satellite and ground-based records is presented. Ozone increase in the upper stratosphere is confirmed, with significant trends at most latitudes. In this altitude region, a very good agreement is found with trends derived from chemistry–climate model simulations. Observed and modelled trends diverge in the lower stratosphere, but the differences are non-significant.
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.
Omaira E. García, Esther Sanromá, Frank Hase, Matthias Schneider, Sergio Fabián León-Luis, Thomas Blumenstock, Eliezer Sepúlveda, Carlos Torres, Natalia Prats, Alberto Redondas, and Virgilio Carreño
Atmos. Meas. Tech., 15, 4547–4567, https://doi.org/10.5194/amt-15-4547-2022, https://doi.org/10.5194/amt-15-4547-2022, 2022
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Retrieving high-precision concentrations of atmospheric trace gases from FTIR (Fourier transform infrared) spectrometry requires a precise knowledge of the instrumental performance. In this context, this paper examines the impact on the ozone (O3) retrievals of several approaches used to characterise the instrumental line shape (ILS) function of ground-based FTIR spectrometers within NDACC (Network for the Detection of Atmospheric Composition Change).
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.
Cyril Brunner, Benjamin T. Brem, Martine Collaud Coen, Franz Conen, Martin Steinbacher, Martin Gysel-Beer, and Zamin A. Kanji
Atmos. Chem. Phys., 22, 7557–7573, https://doi.org/10.5194/acp-22-7557-2022, https://doi.org/10.5194/acp-22-7557-2022, 2022
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Microscopic particles called ice-nucleating particles (INPs) are essential for ice crystals to form in clouds. INPs are a tiny proportion of atmospheric aerosol, and their abundance is poorly constrained. We study how the concentration of INPs changes diurnally and seasonally at a mountaintop station in central Europe. Unsurprisingly, a diurnal cycle is only found when considering air masses that have had lower-altitude ground contact. The highest INP concentrations occur in spring.
Noah Bernays, Daniel A. Jaffe, Irina Petropavlovskikh, and Peter Effertz
Atmos. Meas. Tech., 15, 3189–3192, https://doi.org/10.5194/amt-15-3189-2022, https://doi.org/10.5194/amt-15-3189-2022, 2022
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Ozone is an important pollutant that impacts millions of people worldwide. It is therefore important to ensure accurate measurements. A recent surge in wildfire activity in the USA has resulted in significant enhancements in ozone concentration. However given the nature of wildfire smoke, there are questions about our ability to accurately measure ozone. In this comment, we discuss possible biases in the UV measurements of ozone in the presence of smoke.
Omaira Elena García, Esther Sanromá, Matthias Schneider, Frank Hase, Sergio Fabián León-Luis, Thomas Blumenstock, Eliezer Sepúlveda, Alberto Redondas, Virgilio Carreño, Carlos Torres, and Natalia Prats
Atmos. Meas. Tech., 15, 2557–2577, https://doi.org/10.5194/amt-15-2557-2022, https://doi.org/10.5194/amt-15-2557-2022, 2022
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Accurate observations of atmospheric ozone (O3) are essential to monitor in detail its key role in atmospheric chemistry. In this context, this paper has assessed the effect of using different retrieval strategies on the quality of O3 products from ground-based NDACC FTIR (Fourier transform infrared) spectrometry, with the aim of providing an improved O3 retrieval that could be applied at any NDACC FTIR station.
Shima Bahramvash Shams, Von P. Walden, James W. Hannigan, William J. Randel, Irina V. Petropavlovskikh, Amy H. Butler, and Alvaro de la Cámara
Atmos. Chem. Phys., 22, 5435–5458, https://doi.org/10.5194/acp-22-5435-2022, https://doi.org/10.5194/acp-22-5435-2022, 2022
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Large-scale atmospheric circulation has a strong influence on ozone in the Arctic, and certain anomalous dynamical events, such as sudden stratospheric warmings, cause dramatic alterations of the large-scale circulation. A reanalysis model is evaluated and then used to investigate the impact of sudden stratospheric warmings on mid-atmospheric ozone. Results show that the position of the cold jet stream over the Arctic before these events influences the variability of ozone.
Makoto Saito, Tomohiro Shiraishi, Ryuichi Hirata, Yosuke Niwa, Kazuyuki Saito, Martin Steinbacher, Doug Worthy, and Tsuneo Matsunaga
Biogeosciences, 19, 2059–2078, https://doi.org/10.5194/bg-19-2059-2022, https://doi.org/10.5194/bg-19-2059-2022, 2022
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This study tested combinations of two sources of AGB data and two sources of LCC data and used the same burned area satellite data to estimate BB CO emissions. Our analysis showed large discrepancies in annual mean CO emissions and explicit differences in the simulated CO concentrations among the BB emissions estimates. This study has confirmed that BB emissions estimates are sensitive to the land surface information on which they are based.
Juan Cuesta, Lorenzo Costantino, Matthias Beekmann, Guillaume Siour, Laurent Menut, Bertrand Bessagnet, Tony C. Landi, Gaëlle Dufour, and Maxim Eremenko
Atmos. Chem. Phys., 22, 4471–4489, https://doi.org/10.5194/acp-22-4471-2022, https://doi.org/10.5194/acp-22-4471-2022, 2022
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We present the first comprehensive study integrating satellite observations of near-surface ozone pollution, surface in situ measurements, and a chemistry-transport model for quantifying the role of anthropogenic emission reductions during the COVID-19 lockdown in spring 2020. It confirms the occurrence of a net enhancement of ozone in central Europe and a reduction elsewhere, except for some hotspots, linked with the reduction of precursor emissions from Europe and the Northern Hemisphere.
Irina Petropavlovskikh, Koji Miyagawa, Audra McClure-Beegle, Bryan Johnson, Jeannette Wild, Susan Strahan, Krzysztof Wargan, Richard Querel, Lawrence Flynn, Eric Beach, Gerard Ancellet, and Sophie Godin-Beekmann
Atmos. Meas. Tech., 15, 1849–1870, https://doi.org/10.5194/amt-15-1849-2022, https://doi.org/10.5194/amt-15-1849-2022, 2022
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The Montreal Protocol and its amendments assure the recovery of the stratospheric ozone layer that protects the Earth from harmful ultraviolet radiation. To monitor ozone recovery, multiple satellites and ground-based observational platforms collect ozone data. The changes in instruments can influence the continuation of the ozone data. We discuss a method to remove instrumental artifacts from ozone records to improve the internal consistency among multiple observational records.
Henry Bowman, Steven Turnock, Susanne E. Bauer, Kostas Tsigaridis, Makoto Deushi, Naga Oshima, Fiona M. O'Connor, Larry Horowitz, Tongwen Wu, Jie Zhang, Dagmar Kubistin, and David D. Parrish
Atmos. Chem. Phys., 22, 3507–3524, https://doi.org/10.5194/acp-22-3507-2022, https://doi.org/10.5194/acp-22-3507-2022, 2022
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A full understanding of ozone in the troposphere requires investigation of its temporal variability over all timescales. Model simulations show that the northern midlatitude ozone seasonal cycle shifted with industrial development (1850–2014), with an increasing magnitude and a later summer peak. That shift reached a maximum in the mid-1980s, followed by a reversal toward the preindustrial cycle. The few available observations, beginning in the 1970s, are consistent with the model simulations.
Andrew O. Langford, Christoph J. Senff, Raul J. Alvarez II, Ken C. Aikin, Sunil Baidar, Timothy A. Bonin, W. Alan Brewer, Jerome Brioude, Steven S. Brown, Joel D. Burley, Dani J. Caputi, Stephen A. Conley, Patrick D. Cullis, Zachary C. J. Decker, Stéphanie Evan, Guillaume Kirgis, Meiyun Lin, Mariusz Pagowski, Jeff Peischl, Irina Petropavlovskikh, R. Bradley Pierce, Thomas B. Ryerson, Scott P. Sandberg, Chance W. Sterling, Ann M. Weickmann, and Li Zhang
Atmos. Chem. Phys., 22, 1707–1737, https://doi.org/10.5194/acp-22-1707-2022, https://doi.org/10.5194/acp-22-1707-2022, 2022
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The Fires, Asian, and Stratospheric Transport–Las Vegas Ozone Study (FAST-LVOS) combined lidar, aircraft, and in situ measurements with global models to investigate the contributions of stratospheric intrusions, regional and Asian pollution, and wildfires to background ozone in the southwestern US during May and June 2017 and demonstrated that these processes contributed to background ozone levels that exceeded 70 % of the US National Ambient Air Quality Standard during the 6-week campaign.
Qiansi Tu, Frank Hase, Matthias Schneider, Omaira García, Thomas Blumenstock, Tobias Borsdorff, Matthias Frey, Farahnaz Khosrawi, Alba Lorente, Carlos Alberti, Juan J. Bustos, André Butz, Virgilio Carreño, Emilio Cuevas, Roger Curcoll, Christopher J. Diekmann, Darko Dubravica, Benjamin Ertl, Carme Estruch, Sergio Fabián León-Luis, Carlos Marrero, Josep-Anton Morgui, Ramón Ramos, Christian Scharun, Carsten Schneider, Eliezer Sepúlveda, Carlos Toledano, and Carlos Torres
Atmos. Chem. Phys., 22, 295–317, https://doi.org/10.5194/acp-22-295-2022, https://doi.org/10.5194/acp-22-295-2022, 2022
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We use different methane ground- and space-based remote sensing data sets for investigating the emission strength of three waste disposal sites close to Madrid. We present a method that uses wind-assigned anomalies for deriving emission strengths from satellite data and estimate their uncertainty to 9–14 %. The emission strengths estimated from the remote sensing data sets are significantly larger than the values published in the official register.
Cyril Brunner, Benjamin T. Brem, Martine Collaud Coen, Franz Conen, Maxime Hervo, Stephan Henne, Martin Steinbacher, Martin Gysel-Beer, and Zamin A. Kanji
Atmos. Chem. Phys., 21, 18029–18053, https://doi.org/10.5194/acp-21-18029-2021, https://doi.org/10.5194/acp-21-18029-2021, 2021
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Special microscopic particles called ice-nucleating particles (INPs) are essential for ice crystals to form in the atmosphere. INPs are sparse and their atmospheric concentration and properties are not well understood. Mineral dust particles make up a significant fraction of INPs but how much remains unknown. Here, we address this knowledge gap by studying periods when mineral particles are present in large quantities at a mountaintop station in central Europe.
Larissa Lacher, Hans-Christian Clemen, Xiaoli Shen, Stephan Mertes, Martin Gysel-Beer, Alireza Moallemi, Martin Steinbacher, Stephan Henne, Harald Saathoff, Ottmar Möhler, Kristina Höhler, Thea Schiebel, Daniel Weber, Jann Schrod, Johannes Schneider, and Zamin A. Kanji
Atmos. Chem. Phys., 21, 16925–16953, https://doi.org/10.5194/acp-21-16925-2021, https://doi.org/10.5194/acp-21-16925-2021, 2021
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We investigate ice-nucleating particle properties at Jungfraujoch during the 2017 joint INUIT/CLACE field campaign, to improve the knowledge about those rare particles in a cloud-relevant environment. By quantifying ice-nucleating particles in parallel to single-particle mass spectrometry measurements, we find that mineral dust and aged sea spray particles are potential candidates for ice-nucleating particles. Our findings are supported by ice residual analysis and source region modeling.
Gaëlle Dufour, Didier Hauglustaine, Yunjiang Zhang, Maxim Eremenko, Yann Cohen, Audrey Gaudel, Guillaume Siour, Mathieu Lachatre, Axel Bense, Bertrand Bessagnet, Juan Cuesta, Jerry Ziemke, Valérie Thouret, and Bo Zheng
Atmos. Chem. Phys., 21, 16001–16025, https://doi.org/10.5194/acp-21-16001-2021, https://doi.org/10.5194/acp-21-16001-2021, 2021
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The IASI observations and the LMDZ-OR-INCA model simulations show negative ozone trends in the Central East China region in the lower free (3–6 km column) and the upper free (6–9 km column) troposphere. Sensitivity studies from the model show that the Chinese anthropogenic emissions contribute to more than 50 % in the trend. The reduction in NOx emissions that has occurred since 2013 in China seems to lead to a decrease in ozone in the free troposphere, contrary to the increase at the surface.
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Short summary
We investigated the impact of societal restriction measures during the COVID-19 pandemic on surface ozone at 41 high-elevation sites worldwide. Negative ozone anomalies were observed for spring and summer 2020 for all of the regions considered. In 2021, negative anomalies continued for Europe and partially for the eastern US, while western US sites showed positive anomalies due to wildfires. IASI satellite data and the Carbon Monitor supported emission reductions as a cause of the anomalies.
We investigated the impact of societal restriction measures during the COVID-19 pandemic on...
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