Articles | Volume 26, issue 8
https://doi.org/10.5194/acp-26-5477-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Special issue:
https://doi.org/10.5194/acp-26-5477-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
22 Apr 2026
Research article |
| 22 Apr 2026
Observational insights into atmospheric CO2 and CO at the urban canopy layer top in Metropolitan Shanghai, China
Shuang Fu
Zhejiang Carbon Neutral Innovation Institute & Zhejiang International Cooperation Base for Science and Technology on Carbon Emission Reduction and Monitoring, Zhejiang University of Technology, Hangzhou, China
State Key Laboratory of Green Chemical Synthesis and Conversion, Zhejiang University of Technology, Hangzhou, China
Xuemei Qing
College of Environment, Zhejiang University of Technology, Hangzhou, China
Kunpeng Zang
Zhejiang Carbon Neutral Innovation Institute & Zhejiang International Cooperation Base for Science and Technology on Carbon Emission Reduction and Monitoring, Zhejiang University of Technology, Hangzhou, China
College of Environment, Zhejiang University of Technology, Hangzhou, China
Yi Lin
Zhejiang Carbon Neutral Innovation Institute & Zhejiang International Cooperation Base for Science and Technology on Carbon Emission Reduction and Monitoring, Zhejiang University of Technology, Hangzhou, China
College of Environment, Zhejiang University of Technology, Hangzhou, China
Shuo Liu
Zhejiang Carbon Neutral Innovation Institute & Zhejiang International Cooperation Base for Science and Technology on Carbon Emission Reduction and Monitoring, Zhejiang University of Technology, Hangzhou, China
College of Environment, Zhejiang University of Technology, Hangzhou, China
Yuanyuan Chen
Zhejiang Carbon Neutral Innovation Institute & Zhejiang International Cooperation Base for Science and Technology on Carbon Emission Reduction and Monitoring, Zhejiang University of Technology, Hangzhou, China
College of Environment, Zhejiang University of Technology, Hangzhou, China
Bingjiang Chen
Zhejiang Carbon Neutral Innovation Institute & Zhejiang International Cooperation Base for Science and Technology on Carbon Emission Reduction and Monitoring, Zhejiang University of Technology, Hangzhou, China
College of Environment, Zhejiang University of Technology, Hangzhou, China
Wei Gao
Yangtze River Delta Center for Environmental Meteorology Prediction and Warning, Shanghai, China
Martin Steinbacher
Laboratory for Air Pollution/Environmental Technology, Empa, 8600 Dübendorf, Switzerland
Shuangxi Fang
CORRESPONDING AUTHOR
Zhejiang Carbon Neutral Innovation Institute & Zhejiang International Cooperation Base for Science and Technology on Carbon Emission Reduction and Monitoring, Zhejiang University of Technology, Hangzhou, China
College of Environment, Zhejiang University of Technology, Hangzhou, China
Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters (CIC-FEMD), Nanjing University of Information Science & Technology, Nanjing, China
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EGUsphere, https://doi.org/10.5194/egusphere-2026-265, https://doi.org/10.5194/egusphere-2026-265, 2026
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Carbon dioxide and methane are the two main anthropogenic greenhouse gases responsible for current climate change. Beside the measurement of their atmospheric concentration, the analysis of the abundance of their isotope carbon-14 (14C) gives hints about their origin, either biogenic or fossil. Here we present six years of atmospheric 14CH4 and 14CO2 measurements at a high-elevation alpine site in Switzerland (Jungfraujoch) and discuss the observed trends in both local and global views.
Bernard Grobety, Philippe Favreau, Juanita Rausch, David Jaramillo, Martin Steinbacher, and Christoph Neururer
Aerosol Research Discuss., https://doi.org/10.5194/ar-2026-6, https://doi.org/10.5194/ar-2026-6, 2026
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The iberulite fall was, to our knowledge, the first reported in central Europe. Special was, that the fall was observed in-situ and that the meteorological conditions during the fall are well known. The meteorology, the particle size distribution inside the iberulites, and the presence of a Greenfield gap in the latter strongly corroborates below-cloud scavenging as probable formation mechanism.
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.
Shuo Liu, Zeping Jin, Ziyi Chen, Haolin Li, Zihan Fan, Shaohui Li, Haiwang Fu, Wei He, Kunpeng Zang, Shuangxi Fang, and Peng Yan
EGUsphere, https://doi.org/10.5194/egusphere-2025-5065, https://doi.org/10.5194/egusphere-2025-5065, 2025
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We studied how planting green manure between tea rows affects carbon dioxide release from tea fields. Mixing legume and grass species improved soil health, reduced emissions from tea rows, and stabilized carbon over time. Although inter-row areas released more carbon, overall emissions declined with continued intercropping. This shows that green manure can make tea farming more climate-friendly and sustainable.
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.
Leonie Bernet, Benjamin T. Brem, Nicolas Bukowiecki, Stephan Henne, Jörg Klausen, Mathew Mutuku, David Njiru, Patricia Nying'uro, Christoph Zellweger, and Martin Steinbacher
EGUsphere, https://doi.org/10.5194/egusphere-2025-5272, https://doi.org/10.5194/egusphere-2025-5272, 2025
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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.
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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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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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.
Davide Putero, Paolo Cristofanelli, Kai-Lan Chang, Gaëlle Dufour, Gregory Beachley, Cédric Couret, Peter Effertz, Daniel A. Jaffe, Dagmar Kubistin, Jason Lynch, Irina Petropavlovskikh, Melissa Puchalski, Timothy Sharac, Barkley C. Sive, Martin Steinbacher, Carlos Torres, and Owen R. Cooper
Atmos. Chem. Phys., 23, 15693–15709, https://doi.org/10.5194/acp-23-15693-2023, https://doi.org/10.5194/acp-23-15693-2023, 2023
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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.
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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Jiaxin Li, Kunpeng Zang, Yi Lin, Yuanyuan Chen, Shuo Liu, Shanshan Qiu, Kai Jiang, Xuemei Qing, Haoyu Xiong, Haixiang Hong, Shuangxi Fang, Honghui Xu, and Yujun Jiang
Atmos. Meas. Tech., 16, 4757–4768, https://doi.org/10.5194/amt-16-4757-2023, https://doi.org/10.5194/amt-16-4757-2023, 2023
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Based on observed data of CO2 and CH4 and meteorological parameters over the Yellow Sea in November 2012 and June 2013, a data process and quality control method was optimized and established to filter the data influenced by multiple factors. Spatial and seasonal variations in CO2 and CH4 mixing ratios were mainly controlled by the East Asian Monsoon, while the influence of air–sea exchange was slight.
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.
Simone M. Pieber, Béla Tuzson, Stephan Henne, Ute Karstens, Christoph Gerbig, Frank-Thomas Koch, Dominik Brunner, Martin Steinbacher, and Lukas Emmenegger
Atmos. Chem. Phys., 22, 10721–10749, https://doi.org/10.5194/acp-22-10721-2022, https://doi.org/10.5194/acp-22-10721-2022, 2022
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Understanding regional greenhouse gas emissions into the atmosphere is a prerequisite to mitigate climate change. In this study, we investigated the regional contributions of carbon dioxide (CO2) at the location of the high Alpine observatory Jungfraujoch (JFJ, Switzerland, 3580 m a.s.l.). To this purpose, we combined receptor-oriented atmospheric transport simulations for CO2 concentration in the period 2009–2017 with stable carbon isotope (δ13C–CO2) information.
Matthias Schneider, Benjamin Ertl, Qiansi Tu, Christopher J. Diekmann, Farahnaz Khosrawi, Amelie N. Röhling, Frank Hase, Darko Dubravica, Omaira E. García, Eliezer Sepúlveda, Tobias Borsdorff, Jochen Landgraf, Alba Lorente, André Butz, Huilin Chen, Rigel Kivi, Thomas Laemmel, Michel Ramonet, Cyril Crevoisier, Jérome Pernin, Martin Steinbacher, Frank Meinhardt, Kimberly Strong, Debra Wunch, Thorsten Warneke, Coleen Roehl, Paul O. Wennberg, Isamu Morino, Laura T. Iraci, Kei Shiomi, Nicholas M. Deutscher, David W. T. Griffith, Voltaire A. Velazco, and David F. Pollard
Atmos. Meas. Tech., 15, 4339–4371, https://doi.org/10.5194/amt-15-4339-2022, https://doi.org/10.5194/amt-15-4339-2022, 2022
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We present a computationally very efficient method for the synergetic use of level 2 remote-sensing data products. We apply the method to IASI vertical profile and TROPOMI total column space-borne methane observations and thus gain sensitivity for the tropospheric methane partial columns, which is not achievable by the individual use of TROPOMI and IASI. These synergetic effects are evaluated theoretically and empirically by inter-comparisons to independent references of TCCON, AirCore, and GAW.
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.
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.
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.
Alex Resovsky, Michel Ramonet, Leonard Rivier, Jerome Tarniewicz, Philippe Ciais, Martin Steinbacher, Ivan Mammarella, Meelis Mölder, Michal Heliasz, Dagmar Kubistin, Matthias Lindauer, Jennifer Müller-Williams, Sebastien Conil, and Richard Engelen
Atmos. Meas. Tech., 14, 6119–6135, https://doi.org/10.5194/amt-14-6119-2021, https://doi.org/10.5194/amt-14-6119-2021, 2021
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We present a technical description of a statistical methodology for extracting synoptic- and seasonal-length anomalies from greenhouse gas time series. The definition of what represents an anomalous signal is somewhat subjective, which we touch on throughout the paper. We show, however, that the method performs reasonably well in extracting portions of time series influenced by significant North Atlantic Oscillation weather episodes and continent-wide terrestrial biospheric aberrations.
Dac-Loc Nguyen, Hendryk Czech, Simone M. Pieber, Jürgen Schnelle-Kreis, Martin Steinbacher, Jürgen Orasche, Stephan Henne, Olga B. Popovicheva, Gülcin Abbaszade, Guenter Engling, Nicolas Bukowiecki, Nhat-Anh Nguyen, Xuan-Anh Nguyen, and Ralf Zimmermann
Atmos. Chem. Phys., 21, 8293–8312, https://doi.org/10.5194/acp-21-8293-2021, https://doi.org/10.5194/acp-21-8293-2021, 2021
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Southeast Asia is well-known for emission-intense and recurring wildfires and after-harvest crop residue burning during the pre-monsoon season from February to April. We describe a biomass burning (BB) plume arriving at remote Pha Din meteorological station, outline its carbonaceous particulate matter (PM) constituents based on more than 50 target compounds and discuss possible BB sources. This study adds valuable information on chemical PM composition for a region with scarce data availability.
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Short summary
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.
Urban carbon dynamics are critical for climate action, yet remote background monitoring often...
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