Articles | Volume 25, issue 17
https://doi.org/10.5194/acp-25-9885-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/acp-25-9885-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
05 Sep 2025
Research article |
| 05 Sep 2025
| 05 Sep 2025
Changes in global atmospheric oxidant chemistry from land cover conversion
Atmospheric Chemistry Department, Max Planck Institute for Chemistry, Mainz, Germany
Institute for Atmospheric Physics, Johannes Gutenberg University Mainz, Mainz, Germany
Sergey Gromov
Atmospheric Chemistry Department, Max Planck Institute for Chemistry, Mainz, Germany
Clara M. Nussbaumer
Institute for Atmospheric and Climate Science, ETH Zürich, Zurich, Switzerland
Laura Stecher
Deutsches Zentrum für Luft- und Raumfahrt, Institut für Physik der Atmosphäre, Oberpfaffenhofen, Germany
now at: Centre for Atmospheric Science, Yusuf Hamied Department of Chemistry, University of Cambridge, Cambridge, UK
Matthias Kohl
Atmospheric Chemistry Department, Max Planck Institute for Chemistry, Mainz, Germany
Samuel Ruhl
Atmospheric Chemistry Department, Max Planck Institute for Chemistry, Mainz, Germany
Holger Tost
Institute for Atmospheric Physics, Johannes Gutenberg University Mainz, Mainz, Germany
Jos Lelieveld
Atmospheric Chemistry Department, Max Planck Institute for Chemistry, Mainz, Germany
Climate and Atmosphere Research Center, The Cyprus Institute, Nicosia, Cyprus
Andrea Pozzer
Atmospheric Chemistry Department, Max Planck Institute for Chemistry, Mainz, Germany
Climate and Atmosphere Research Center, The Cyprus Institute, Nicosia, Cyprus
Related authors
Matthias Kohl, Christoph Brühl, Holger Tost, Christos Xenofontos, Theodoros Christoudias, Sergey Gromov, Oliver Appel, Stephan Borrmann, Adam Bourassa, Pedro Campunzano-Jost, Yafang Cheng, Oliver Eppers, Karl D. Froyd, Bruna A. Holanda, Jose L. Jimenez, Patrick Jöckel, Philipp Joppe, Katharina Kaiser, Joseph M. Katich, Klaus Klingmüller, Franziska Köllner, Agnieszka Kupc, Anna Martin, Christopher Pöhlker, Mira L. Pöhlker, Ulrich Pöschl, Landon Rieger, Samuel Ruhl, Gregory P. Schill, Johannes Schneider, Christiane Schulz, Joshua P. Schwarz, Alexandra P. Tsimpidi, Ryan Vella, Christina J. Williamson, Yifan Yang, Daniel Zawada, Jos Lelieveld, and Andrea Pozzer
EGUsphere, https://doi.org/10.5194/egusphere-2026-3649, https://doi.org/10.5194/egusphere-2026-3649, 2026
This preprint is open for discussion and under review for Atmospheric Chemistry and Physics (ACP).
Short summary
Short summary
Aerosols are crucial for Earth's climate, yet their vertical distribution remains poorly understood. We present first consistent global simulations of aerosol distributions and composition from the Earth's surface to the stratosphere, validated by extensive observations. Key findings include a global minimum in aerosol mass in the free troposphere, a significant contribution of organic aerosol in the lower stratosphere, and limited transport of primary particles to the stratosphere.
Ryan Vella and Ulrike Lohmann
EGUsphere, https://doi.org/10.5194/egusphere-2026-2961, https://doi.org/10.5194/egusphere-2026-2961, 2026
Short summary
Short summary
The Atlantic Ocean's overturning circulation transports heat northward and may weaken under climate change. We show that this weakening redistributes natural dust and other particles across the atmosphere, altering cloud properties worldwide. Clouds become thinner in cold regions, reducing their ability to cool the planet. This produces a warming effect of about 0.84 watts per square metre that partially counteracts the cooling from a weaker circulation.
Daniele Visioni, Alan Robock, Alistair Duffey, Matthew Henry, Haruki Hirasawa, Walker R. Lee, Cindy Wang, Kelsey Roberts, Shingo Watanabe, Michelle S. Reboita, Masahiro Sugiyama, Ben Kravitz, Jim Haywood, Simone Tilmes, Frederic Bonou, Jack Chen, Timofei Sukodolov, Sandro Vattioni, Andrin Jörimann, Diego Villanueva, Ryan Vella, Paul Farron, Ewa M. Bednarz, Ulrike Niemeier, Colleen Golja, and Juan A. Anel
EGUsphere, https://doi.org/10.5194/egusphere-2026-2417, https://doi.org/10.5194/egusphere-2026-2417, 2026
This preprint is open for discussion and under review for Geoscientific Model Development (GMD).
Short summary
Short summary
The Geoengineering Model Intercomparison Project is a coordinated international model intercomparison effort aiming to provide robust experimental protocols for simulations of various Solar Radiation Modification (SRM) methods. In this manuscript, we describe a list of novel experiments decided by the community, to be run by climate models to better understand sources of uncertainty in SRM. We also show and discuss some preliminary results from a few climate models.
Ryan Vella, Matthew Forrest, Andrea Pozzer, Alexandra P. Tsimpidi, Thomas Hickler, Jos Lelieveld, and Holger Tost
Atmos. Chem. Phys., 25, 243–262, https://doi.org/10.5194/acp-25-243-2025, https://doi.org/10.5194/acp-25-243-2025, 2025
Short summary
Short summary
This study examines how land cover changes influence biogenic volatile organic compound (BVOC) emissions and atmospheric states. Using a coupled chemistry–climate–vegetation model, we compare present-day land cover (deforested for crops and grazing) with natural vegetation and an extreme reforestation scenario. We find that vegetation changes significantly impact global BVOC emissions and organic aerosols but have a relatively small effect on total aerosols, clouds, and radiative effects.
Ryan Vella, Andrea Pozzer, Matthew Forrest, Jos Lelieveld, Thomas Hickler, and Holger Tost
Biogeosciences, 20, 4391–4412, https://doi.org/10.5194/bg-20-4391-2023, https://doi.org/10.5194/bg-20-4391-2023, 2023
Short summary
Short summary
We investigated the effect of the El Niño–Southern Oscillation (ENSO) on biogenic volatile organic compound (BVOC) emissions from plants. ENSO events can cause a significant increase in these emissions, which have a long-term impact on the Earth's atmosphere. Persistent ENSO conditions can cause long-term changes in vegetation, resulting in even higher BVOC emissions. We link ENSO-induced emission anomalies with driving atmospheric and vegetational variables.
Ryan Vella, Matthew Forrest, Jos Lelieveld, and Holger Tost
Geosci. Model Dev., 16, 885–906, https://doi.org/10.5194/gmd-16-885-2023, https://doi.org/10.5194/gmd-16-885-2023, 2023
Short summary
Short summary
Biogenic volatile organic compounds (BVOCs) are released by vegetation and have a major impact on atmospheric chemistry and aerosol formation. Non-interacting vegetation constrains the majority of numerical models used to estimate global BVOC emissions, and thus, the effects of changing vegetation on emissions are not addressed. In this work, we replace the offline vegetation with dynamic vegetation states by linking a chemistry–climate model with a global dynamic vegetation model.
Matthias Kohl, Christoph Brühl, Holger Tost, Christos Xenofontos, Theodoros Christoudias, Sergey Gromov, Oliver Appel, Stephan Borrmann, Adam Bourassa, Pedro Campunzano-Jost, Yafang Cheng, Oliver Eppers, Karl D. Froyd, Bruna A. Holanda, Jose L. Jimenez, Patrick Jöckel, Philipp Joppe, Katharina Kaiser, Joseph M. Katich, Klaus Klingmüller, Franziska Köllner, Agnieszka Kupc, Anna Martin, Christopher Pöhlker, Mira L. Pöhlker, Ulrich Pöschl, Landon Rieger, Samuel Ruhl, Gregory P. Schill, Johannes Schneider, Christiane Schulz, Joshua P. Schwarz, Alexandra P. Tsimpidi, Ryan Vella, Christina J. Williamson, Yifan Yang, Daniel Zawada, Jos Lelieveld, and Andrea Pozzer
EGUsphere, https://doi.org/10.5194/egusphere-2026-3649, https://doi.org/10.5194/egusphere-2026-3649, 2026
This preprint is open for discussion and under review for Atmospheric Chemistry and Physics (ACP).
Short summary
Short summary
Aerosols are crucial for Earth's climate, yet their vertical distribution remains poorly understood. We present first consistent global simulations of aerosol distributions and composition from the Earth's surface to the stratosphere, validated by extensive observations. Key findings include a global minimum in aerosol mass in the free troposphere, a significant contribution of organic aerosol in the lower stratosphere, and limited transport of primary particles to the stratosphere.
Lasse Moormann, Friederike Fachinger, Holger Tost, and Frank Drewnick
EGUsphere, https://doi.org/10.5194/egusphere-2026-2494, https://doi.org/10.5194/egusphere-2026-2494, 2026
This preprint is open for discussion and under review for Atmospheric Chemistry and Physics (ACP).
Short summary
Short summary
Using drone-based vertical profiling, we a) compare the sensitivity of various meteorological and trace substances to detect mixing layer heights at night, b) investigate the dependency of the vertical trace matter distribution on irradiance and mixing layer heights and c) evaluate the representativity of ground-based measured variables for the lowermost troposphere and finally provide suggestions to enhance the representativity of ground-based measurement stations.
Lasse Moormann, Friederike Fachinger, Frank Drewnick, and Holger Tost
Atmos. Chem. Phys., 26, 8455–8474, https://doi.org/10.5194/acp-26-8455-2026, https://doi.org/10.5194/acp-26-8455-2026, 2026
Short summary
Short summary
We examine boundary layer (BL) processes during summer rain in Germany, focusing on air mass exchange and precipitation effects. Using drone and ground observations, and ICON (ICOsahedral Nonhydrostatic) model data, we link delayed BL breakup and weak vertical mixing to aerosol formation and chemical processes. ICON predicts mixing layer height under stable conditions but underestimates it during cold pool events, enhancing understanding of frontal weather scenarios and atmospheric changes.
Jianzhong Ma, Bin Chen, Qianshan He, Xiaolu Yan, Gaili Wang, Siyang Cheng, Benedikt Steil, Christoph Brühl, Holger Tost, Michael Höpfner, Andrea Pozzer, and Jos Lelieveld
Atmos. Chem. Phys., 26, 8125–8144, https://doi.org/10.5194/acp-26-8125-2026, https://doi.org/10.5194/acp-26-8125-2026, 2026
Short summary
Short summary
We use a global atmospheric chemistry and climate model to study the efficiency and effectiveness of the deep convective transport of CO, NH3 and SO2 from the planetary boundary layer into the Asian summer monsoon anticyclone. We find that in contrast to CO and NH3, the SO2 enhancements within the anticyclone are very weak. The wet scavenging over South Asia is more effective for SO2 than NH3 at reducing their amounts reaching the Tibetan Plateau and the Asian summer monsoon anticyclone.
Ryan Vella and Ulrike Lohmann
EGUsphere, https://doi.org/10.5194/egusphere-2026-2961, https://doi.org/10.5194/egusphere-2026-2961, 2026
Short summary
Short summary
The Atlantic Ocean's overturning circulation transports heat northward and may weaken under climate change. We show that this weakening redistributes natural dust and other particles across the atmosphere, altering cloud properties worldwide. Clouds become thinner in cold regions, reducing their ability to cool the planet. This produces a warming effect of about 0.84 watts per square metre that partially counteracts the cooling from a weaker circulation.
Johanna Margaretha Schüttler, Giovanni Pugliese, Joseph Byron, Cléo Quaresma Dias-Júnior, Carolina de A. Monteiro, Hartwig Harder, Jos Lelieveld, and Jonathan Williams
Biogeosciences, 23, 3467–3498, https://doi.org/10.5194/bg-23-3467-2026, https://doi.org/10.5194/bg-23-3467-2026, 2026
Short summary
Short summary
We measured how Amazon rainforest soils release and uptake compounds commonly produced by plants across seasons, including the severe 2023 El Niño drought. Soils took up isoprene most in the afternoon of dry seasons, while emissions of very reactive sesquiterpenes peaked during the drought. Removing the leaf litter changed which compounds transferred to and from the soil. These soil exchanges, though small compared to the canopy, can shape air chemistry near the ground and influence soil biota.
Gunther N. T. E. Türk, Simone T. Andersen, Patrick Dewald, Jan Schuladen, Jos Lelieveld, and John N. Crowley
EGUsphere, https://doi.org/10.5194/egusphere-2026-2487, https://doi.org/10.5194/egusphere-2026-2487, 2026
Short summary
Short summary
We built a small instrument to measure the air-borne molecules NO₃ and N₂O₅. These originate mostly from human-made nitrogen oxide emissions and are important for nighttime chemistry and air quality. Our instrument is lightweight and sensitive, detecting these molecules at levels below one part per trillion. Tests in the laboratory and during a field study show its ability to accurately measure these trace gases. Here, we present the design of the instrument and discuss its performance.
Daniele Visioni, Alan Robock, Alistair Duffey, Matthew Henry, Haruki Hirasawa, Walker R. Lee, Cindy Wang, Kelsey Roberts, Shingo Watanabe, Michelle S. Reboita, Masahiro Sugiyama, Ben Kravitz, Jim Haywood, Simone Tilmes, Frederic Bonou, Jack Chen, Timofei Sukodolov, Sandro Vattioni, Andrin Jörimann, Diego Villanueva, Ryan Vella, Paul Farron, Ewa M. Bednarz, Ulrike Niemeier, Colleen Golja, and Juan A. Anel
EGUsphere, https://doi.org/10.5194/egusphere-2026-2417, https://doi.org/10.5194/egusphere-2026-2417, 2026
This preprint is open for discussion and under review for Geoscientific Model Development (GMD).
Short summary
Short summary
The Geoengineering Model Intercomparison Project is a coordinated international model intercomparison effort aiming to provide robust experimental protocols for simulations of various Solar Radiation Modification (SRM) methods. In this manuscript, we describe a list of novel experiments decided by the community, to be run by climate models to better understand sources of uncertainty in SRM. We also show and discuss some preliminary results from a few climate models.
Hannah Klebach, Martin Heinritzi, Katharina Kaiser, Lisa Beck, Samuel Ruhl, Samira Atabakhsh, Nirvan Bhattacharyya, Lucía Caudillo-Plath, Philipp Joppe, Thomas Klimach, Peter Lloyd, Mira Pöhlker, Ulrich Pöschl, Sarah Richter, Douglas M. Russell, Johannes Schneider, Marcel Zauner-Wieczorek, and Joachim Curtius
EGUsphere, https://doi.org/10.5194/egusphere-2026-2191, https://doi.org/10.5194/egusphere-2026-2191, 2026
Short summary
Short summary
Marine atmospheric aerosols remain a major uncertainty in climate models. We report gas and particle phase measurements of two important aerosol forming vapours, sulfuric acid and methanesulfonic acid in the Indo-Pacific. We find that the latter typically dominates over sulfuric acid and contributes significantly to free tropospheric aerosol. Deep convection transports the precursor of both acids to the upper troposphere, providing a key aerosol source in the pristine remote Pacific Ocean.
Clara M. Nussbaumer, Colette L. Heald, Amanda M. Häne, and Christoph Hüglin
Atmos. Chem. Phys., 26, 5355–5373, https://doi.org/10.5194/acp-26-5355-2026, https://doi.org/10.5194/acp-26-5355-2026, 2026
Short summary
Short summary
Ground-level ozone is harmful to human health. While precursors to ozone were strongly reduced over the past decades, unhealthy levels of ozone are still frequently reported in Switzerland. In this study, we investigate changes in ozone and its relationship with temperature over time. We find that precursor reductions have positively affected ozone in remote locations, while ozone is increasing close to busy roads. High ozone is often associated with hot summer days.
Andries-Jan de Vries, Steven B. Feldstein, Jake W. Casselman, Georgios Fragkoulidis, Jos Lelieveld, and Daniela I. V. Domeisen
EGUsphere, https://doi.org/10.5194/egusphere-2026-1569, https://doi.org/10.5194/egusphere-2026-1569, 2026
Short summary
Short summary
Precipitation in the arid Middle East experiences large year-to-year variations with direct relevance to droughts and floods. This study quantifies the influence of ENSO on Middle East precipitation variability at local and regional scales during the cool season. Three mechanisms contribute to precipitation anomalies: a meridional shift in the subtropical jet, a barotropic Rossby wave response in the extratropics, and a baroclinic response in the regional tropical circulation.
Chun Hang Chau, Peter Hoor, Katharina Kaiser, and Holger Tost
Atmos. Chem. Phys., 26, 3637–3652, https://doi.org/10.5194/acp-26-3637-2026, https://doi.org/10.5194/acp-26-3637-2026, 2026
Short summary
Short summary
This study examines the potential impact of different greenhouse gases to vertical mixing by clear air turbulence in the upper troposphere and lower stratosphere . We found that ozone is most sensitive to vertical mixing and could lead to cooling at the top of the atmosphere by -0.2 W/m2. We also found that the vertical mixing by clear air turbulence could lead to changes in atmospheric chemistry including changing the methane lifetime and the ozone sensitivity.
Anna Martin, Klaus Klingmüller, Benedikt Steil, Sergey Gromov, Yu-Ri Lee, Dong Yeong Chang, Nic Surawski, Jos Lelieveld, Sujong Jeong, and Andrea Pozzer
EGUsphere, https://doi.org/10.5194/egusphere-2026-371, https://doi.org/10.5194/egusphere-2026-371, 2026
Short summary
Short summary
We evaluate a new model simulating soil uptake of methane and hydrogen from the atmosphere. Coupled to an atmospheric chemistry and land surface model, it accounts for weather and soil conditions. Our results match observations, showing accurate removal depending on soil properties, temperature, moisture, and atmospheric conditions. This work improves the model’s ability to represent natural cycles of methane and hydrogen.
Yihan Zou, Jianzhong Ma, Ningwei Liu, Weili Lin, Xiaobin Xu, Yunjia Li, Siyang Cheng, Xiangdong Zheng, Andrea Pozzer, and Jos Lelieveld
EGUsphere, https://doi.org/10.5194/egusphere-2026-499, https://doi.org/10.5194/egusphere-2026-499, 2026
Short summary
Short summary
Our EMAC simulations including the ozone-source-tracing technique show strong seasonal and daily variability in the contributions of ozone from various stratospheric and tropospheric sources to surface ozone over the Tibetan Plateau (TP). Stratospheric contribution is highest in spring. Tropospheric sources from Central Asia, West Asia and Europe cause a summertime maximum over the northern TP. South and Southeast Asian sources lead to peaks in the southern and central TP during the pre-monsoon.
Nic Surawski, Benedikt Steil, Christoph Brühl, Sergey Gromov, Klaus Klingmüller, Anna Martin, Andrea Pozzer, and Jos Lelieveld
Geosci. Model Dev., 19, 911–931, https://doi.org/10.5194/gmd-19-911-2026, https://doi.org/10.5194/gmd-19-911-2026, 2026
Short summary
Short summary
Hydrogen usage will likely increase to achieve net zero emission targets. We undertook calculations with an Earth system model using a high-performance computer to explore hydrogen atmospheric dynamics. Simulations with our model yielded highly accurate results at global scale. Correctly representing hydroxyl radicals in the model is a critical requirement for predicting hydrogen concentrations well. Our hydrogen budget is also in very good agreement with bottom-up literature estimates.
Christoph Brühl, Matthias Kohl, and Jos Lelieveld
Atmos. Chem. Phys., 25, 18697–18718, https://doi.org/10.5194/acp-25-18697-2025, https://doi.org/10.5194/acp-25-18697-2025, 2025
Short summary
Short summary
Simulations with a comprehensive chemistry-climate model show that organic aerosol from recent major forest fires strongly enhances heterogeneous ozone depletion by chlorine in the middle and high latitude lower stratosphere, supported by satellite observations. This sunlight-absorbing, self-lofting aerosol perturbs the radiation budget and stratospheric dynamics differently from major volcanic eruptions, which are also included in this study.
Linda Smoydzin, Vera Bense, Heiko Bozem, Philipp Joppe, Daniel Kunkel, Hans-Christoph Lachnitt, Holger Tost, Andreas Zahn, Helmut Ziereis, Martin Riese, and Peter Hoor
EGUsphere, https://doi.org/10.5194/egusphere-2025-5372, https://doi.org/10.5194/egusphere-2025-5372, 2025
Short summary
Short summary
During a research flight in early October elevated upper tropospheric mixing ratios of CO, NO, NOy and O3 were observed over a distance of more than 1000 km east of the Brasilian coast. Ozone mixing ratios are 20–40 ppbv higher than during a flight in early September. By combining aircraft observations with model simulations we find that ozone production from biomass burning over Amazonia caused predominantly the ozone enhancements which have a local effect on the radiative forcing of 50 mWm−2.
Luis Valero, Konrad Kandler, Sina Jost, Holger Tost, Luca Katarina Eichhorn, Christian von Glahn, Harald Rott, Marilena Flory, Alexandre Baron, Kathie Smith, Troy Thornberry, and Ralf Weigel
EGUsphere, https://doi.org/10.5194/egusphere-2025-5568, https://doi.org/10.5194/egusphere-2025-5568, 2025
Short summary
Short summary
We developed a low-cost, balloon-lifted platform with lightweight instruments to measure particles and collect samples. We tested this platform during two field campaigns in Germany. A case study showed its ability to observe the vertical distribution of particles and how they form cloud droplets. Electronic microscope analysis of the samples identified their chemical composition. This work shows the platform is a capable tool for studying atmospheric processes.
Linda Ort, Andrea Pozzer, Peter Hoor, Florian Obersteiner, Andreas Zahn, Thomas B. Ryerson, Chelsea R. Thompson, Jeff Peischl, Róisín Commane, Bruce Daube, Ilann Bourgeois, Jos Lelieveld, and Horst Fischer
Atmos. Chem. Phys., 25, 14987–15007, https://doi.org/10.5194/acp-25-14987-2025, https://doi.org/10.5194/acp-25-14987-2025, 2025
Short summary
Short summary
This study investigates the role of lightning emissions on the O3–CO ratio in the northern subtropics. We used in situ observations and a global circulation model to show an effect of up to 40 % onto the subtropical O3–CO ratio by tropical air masses transported via the Hadley cell. This influence of lightning emissions and its photochemistry has a global effect on trace and greenhouse gases and needs to be considered for global chemical distributions.
Adrienne Jeske and Holger Tost
Atmos. Chem. Phys., 25, 14435–14448, https://doi.org/10.5194/acp-25-14435-2025, https://doi.org/10.5194/acp-25-14435-2025, 2025
Short summary
Short summary
Thunderstorms lead to a vertical redistribution of tracers throughout the troposphere. We applied a new tool, the convective exchange matrix, in historical simulations with a chemistry–climate model to investigate the trends in convective transport. This reveals that convection reaches higher but that deep convection occurs less often in the time period from 2011 to 2020 than in the 1980s. Thus, convective transport towards the upper troposphere has declined as an adaptation to climate change.
Catherine Acquah, Laura Stecher, Mariano Mertens, and Patrick Jöckel
Atmos. Chem. Phys., 25, 13665–13686, https://doi.org/10.5194/acp-25-13665-2025, https://doi.org/10.5194/acp-25-13665-2025, 2025
Short summary
Short summary
Short-lived ozone precursor species influence the formation of ozone and also the atmospheric lifetime of methane. Our study assesses the effect of two widely used emission inventories of these species on ozone and the methane lifetime. Our results indicate tropospheric ozone and methane lifetime differences of around 4 % even though both emission inventories aim at representing present-day conditions. We further attribute the differences to emissions of individual sectors, e.g. land traffic.
Chun Hang Chau, Peter Hoor, and Holger Tost
Atmos. Chem. Phys., 25, 13123–13140, https://doi.org/10.5194/acp-25-13123-2025, https://doi.org/10.5194/acp-25-13123-2025, 2025
Short summary
Short summary
This study examines how the turbulence in the upper troposphere/lower stratosphere (UTLS) could modify the tracer distribution under different situations. Using a multi-scale chemistry model with a novel diagnostic, we found that both the pre-existing tracer gradient and the dynamical and thermodynamical forcing play a role in modifying the tracer distribution. These results allow further research on the UTLS turbulent mixing and its implications for the climate system.
Sarah Brüning and Holger Tost
Atmos. Chem. Phys., 25, 10797–10822, https://doi.org/10.5194/acp-25-10797-2025, https://doi.org/10.5194/acp-25-10797-2025, 2025
Short summary
Short summary
The connection between convective clouds and severe weather demands a robust characterisation of convective organisation. This study investigates spatio-temporal patterns of convective organisation and their relationship to machine-learning-based 3D cloud properties through a combination of different indices. We analyse how organisation affects cloud and core properties in a tropical domain, revealing overlapping effects of strong and weak organisation that may frequently blur statistics.
Sarah Brüning and Holger Tost
Atmos. Chem. Phys., 25, 10773–10795, https://doi.org/10.5194/acp-25-10773-2025, https://doi.org/10.5194/acp-25-10773-2025, 2025
Short summary
Short summary
This study analyses the temporal variability and life cycle of 3D convective clouds characteristics in the tropics. We derive the data from a machine-learning-based 3D extrapolation of high-resolution 2D satellite data and an object-based detection algorithm. Cloud properties are not only affected by the surface type. Instead, our findings highlight the impact of convective cores on horizontal and vertical cloud and core properties and a potential prolonging of the cloud life cycle.
Xurong Wang, Alexandra P. Tsimpidi, Zhenqi Luo, Benedikt Steil, Andrea Pozzer, Jos Lelieveld, and Vlassis A. Karydis
Atmos. Chem. Phys., 25, 10559–10586, https://doi.org/10.5194/acp-25-10559-2025, https://doi.org/10.5194/acp-25-10559-2025, 2025
Short summary
Short summary
Ammonia (NH3) is an abundant alkaline gas and key precursor in particulate matter formation. While SO2 and NOx emissions have decreased, global NH3 emissions are stable or rising. This study investigates NH3 emission impacts on size-resolved aerosol composition and acidity using the EMAC (ECHAM5/MESSy Atmospheric Chemistry) model, analyzing three emission schemes. Sulfate–nitrate–ammonium aerosols in fine-mode sizes are most sensitive to NH3 changes. Regional responses vary. NH3 buffers aerosol acidity, mitigating pH shifts.
Sina Jost, Ralf Weigel, Konrad Kandler, Luis Valero, Jessica Girdwood, Chris Stopford, Warren Stanley, Luca K. Eichhorn, Christian von Glahn, and Holger Tost
Atmos. Meas. Tech., 18, 4397–4412, https://doi.org/10.5194/amt-18-4397-2025, https://doi.org/10.5194/amt-18-4397-2025, 2025
Short summary
Short summary
For the balloon-borne detection of particles (diameter 0.4 < Dp < 40 µm), the Universal Cloud and Aerosol Sounding System (UCASS) was used, whose sample flow is determined by GPS-measured ascent rates. In flights, actual UCASS sample flows rarely match the ascent rates. Errors are minimised by real-time detection of the UCASS flows, e.g. by implementing a thermal flow sensor (TFS) within the UCASS. The TFSs were tested in flight and calibrated at up to 10 m s−1 and at variable angles of attack.
Mingxuan Wu, Hailong Wang, Zheng Lu, Xiaohong Liu, Huisheng Bian, David D. Cohen, Yan Feng, Mian Chin, Didier A. Hauglustaine, Vlassis A. Karydis, Marianne T. Lund, Gunnar Myhre, Andrea Pozzer, Michael Schulz, Ragnhild B. Skeie, Alexandra P. Tsimpidi, Svetlana G. Tsyro, and Shaocheng Xie
Atmos. Chem. Phys., 25, 10049–10074, https://doi.org/10.5194/acp-25-10049-2025, https://doi.org/10.5194/acp-25-10049-2025, 2025
Short summary
Short summary
A key challenge in simulating the life cycle of nitrate aerosol in global models is accurately representing the mass size distribution of nitrate aerosol, which lacks sufficient observational constraints. We found that most global models underestimate the mass fraction of fine-mode nitrate at the surface in all regions. Our study highlights the importance of gas–aerosol partitioning parameterization and the simulation of dust and sea salt in correctly simulating the mass size distribution of nitrate.
William J. Collins, Fiona M. O'Connor, Rachael E. Byrom, Øivind Hodnebrog, Patrick Jöckel, Mariano Mertens, Gunnar Myhre, Matthias Nützel, Dirk Olivié, Ragnhild Bieltvedt Skeie, Laura Stecher, Larry W. Horowitz, Vaishali Naik, Gregory Faluvegi, Ulas Im, Lee T. Murray, Drew Shindell, Kostas Tsigaridis, Nathan Luke Abraham, and James Keeble
Atmos. Chem. Phys., 25, 9031–9060, https://doi.org/10.5194/acp-25-9031-2025, https://doi.org/10.5194/acp-25-9031-2025, 2025
Short summary
Short summary
We used 7 climate models that include atmospheric chemistry and find that in a scenario with weak controls on air quality, the warming effects (over 2015 to 2050) of decreases in ozone-depleting substances and increases in air quality pollutants are approximately equal and would make ozone the second highest contributor to warming over this period. We find that for stratospheric ozone recovery, the standard measure of climate effects underestimates a more comprehensive measure.
Raphael Dreger, Timo Kirfel, Andrea Pozzer, Simon Rosanka, Rolf Sander, and Domenico Taraborrelli
Geosci. Model Dev., 18, 4273–4291, https://doi.org/10.5194/gmd-18-4273-2025, https://doi.org/10.5194/gmd-18-4273-2025, 2025
Short summary
Short summary
Model simulations are essential for understanding the interactions between atmospheric composition and weather. However, models including chemistry are very slow. Hence, any computation speedup of such models is important for understanding the role of atmospheric chemistry within the Earth system. In this study we analyzed and optimized the time step for chemistry calculations. Our results show that atmospheric models could be run notably faster without any loss in accuracy.
Steven T. Turnock, Dimitris Akritidis, Larry Horowitz, Mariano Mertens, Andrea Pozzer, Carly L. Reddington, Hantao Wang, Putian Zhou, and Fiona O'Connor
Atmos. Chem. Phys., 25, 7111–7136, https://doi.org/10.5194/acp-25-7111-2025, https://doi.org/10.5194/acp-25-7111-2025, 2025
Short summary
Short summary
We assess the drivers behind changes in peak-season surface ozone concentrations and risks to human health between 1850 and 2014. Substantial increases in surface ozone have occurred over this period, resulting in an increased risk to human health, driven mainly by increases in anthropogenic NOx emissions and global CH4 concentrations. Fixing anthropogenic NOx emissions at 1850 values in the near-present-day period can eliminate the risk to human health associated with exposure to surface ozone.
Matthias Kohl, Christoph Brühl, Jennifer Schallock, Holger Tost, Patrick Jöckel, Adrian Jost, Steffen Beirle, Michael Höpfner, and Andrea Pozzer
Geosci. Model Dev., 18, 3985–4007, https://doi.org/10.5194/gmd-18-3985-2025, https://doi.org/10.5194/gmd-18-3985-2025, 2025
Short summary
Short summary
SO2 from explosive volcanic eruptions reaching the stratosphere can oxidize and form sulfur aerosols, potentially persisting for several years. We developed a new submodel, Explosive Volcanic ERuptions (EVER), that seamlessly includes stratospheric volcanic SO2 emissions in global numerical simulations based on a novel standard historical model setup, successfully evaluated with satellite observations. Sensitivity studies on the Nabro eruption in 2011 evaluate different emission methods.
Getachew Agmuas Adnew, Gerbrand Koren, Neha Mehendale, Sergey Gromov, Maarten Krol, and Thomas Röckmann
Atmos. Meas. Tech., 18, 2701–2719, https://doi.org/10.5194/amt-18-2701-2025, https://doi.org/10.5194/amt-18-2701-2025, 2025
Short summary
Short summary
This study presents high-precision measurements of ∆′17O(CO2). Key findings include the extension of the N2O–∆′17O correlation to the upper troposphere and the identification of significant differences in the N2O–∆′17O slope in StratoClim samples. Additionally, the ∆′17O measurements are used to estimate global stratospheric production and surface removal of ∆′17O, providing an independent estimate of global vegetation CO2 exchange.
Simone T. Andersen, Rolf Sander, Patrick Dewald, Laura Wüst, Tobias Seubert, Gunther N. T. E. Türk, Jan Schuladen, Max R. McGillen, Chaoyang Xue, Abdelwahid Mellouki, Alexandre Kukui, Vincent Michoud, Manuela Cirtog, Mathieu Cazaunau, Astrid Bauville, Hichem Bouzidi, Paola Formenti, Cyrielle Denjean, Jean-Claude Etienne, Olivier Garrouste, Christopher Cantrell, Jos Lelieveld, and John N. Crowley
Atmos. Chem. Phys., 25, 5893–5909, https://doi.org/10.5194/acp-25-5893-2025, https://doi.org/10.5194/acp-25-5893-2025, 2025
Short summary
Short summary
Measurements and modelling of reactive nitrogen gases observed in a suburban temperate forest in Rambouillet, France, circa 50 km southwest of Paris in 2022 indicate that the biosphere rapidly scavenges organic nitrates of mixed biogenic and anthropogenic origin, resulting in short lifetimes for, for example, alkyl nitrates and peroxy nitrates.
Laura Stecher, Franziska Winterstein, Patrick Jöckel, Michael Ponater, Mariano Mertens, and Martin Dameris
Atmos. Chem. Phys., 25, 5133–5158, https://doi.org/10.5194/acp-25-5133-2025, https://doi.org/10.5194/acp-25-5133-2025, 2025
Short summary
Short summary
Methane, the second most important anthropogenic greenhouse gas, is chemically decomposed in the atmosphere. The chemical sink of atmospheric methane is not constant but depends on the temperature and on the abundance of its reaction partners. In this study, we use a global chemistry–climate model to assess the feedback of atmospheric methane induced by changes in the chemical sink in a warming climate and its implications for the chemical composition and the surface air temperature change.
Laura Wüst, Patrick Dewald, Gunther N. T. E. Türk, Jos Lelieveld, and John N. Crowley
Atmos. Meas. Tech., 18, 1943–1959, https://doi.org/10.5194/amt-18-1943-2025, https://doi.org/10.5194/amt-18-1943-2025, 2025
Short summary
Short summary
Detection of NO2 via cavity ring-down spectroscopy (CRDS) after thermal dissociation (TD) of alkyl and peroxy nitrates can be used to detect total atmospheric organic nitrates originating from the interaction between biogenic emissions of volatile organic compounds and nitrogen oxides of anthropogenic origin. Here we present an improved TD-CRDS technique that avoids systematic bias resulting from secondary chemistry in the heated inlets and that can be deployed in regions with strong biogenic emissions.
Pantelis Georgiades, Theo Economou, Yiannis Proestos, Jose Araya, Jos Lelieveld, and Marco Neira
Earth Syst. Sci. Data, 17, 1153–1171, https://doi.org/10.5194/essd-17-1153-2025, https://doi.org/10.5194/essd-17-1153-2025, 2025
Short summary
Short summary
Climate change is posing increasing challenges in the dairy cattle farming sector, as heat stress adversely affects the animals' health and milk production. To accurately assess these impacts, we developed a machine learning model to downscale daily climate data to hourly Temperature Humidity Index (THI) values. We utilized historical weather data to train our model and applied them to future climate projections, under two climate scenarios.
Hector Navarro-Barboza, Jordi Rovira, Vincenzo Obiso, Andrea Pozzer, Marta Via, Andres Alastuey, Xavier Querol, Noemi Perez, Marjan Savadkoohi, Gang Chen, Jesus Yus-Díez, Matic Ivancic, Martin Rigler, Konstantinos Eleftheriadis, Stergios Vratolis, Olga Zografou, Maria Gini, Benjamin Chazeau, Nicolas Marchand, Andre S. H. Prevot, Kaspar Dallenbach, Mikael Ehn, Krista Luoma, Tuukka Petäjä, Anna Tobler, Jaroslaw Necki, Minna Aurela, Hilkka Timonen, Jarkko Niemi, Olivier Favez, Jean-Eudes Petit, Jean-Philippe Putaud, Christoph Hueglin, Nicolas Pascal, Aurélien Chauvigné, Sébastien Conil, Marco Pandolfi, and Oriol Jorba
Atmos. Chem. Phys., 25, 2667–2694, https://doi.org/10.5194/acp-25-2667-2025, https://doi.org/10.5194/acp-25-2667-2025, 2025
Short summary
Short summary
Brown carbon (BrC) absorbs ultraviolet (UV) and visible light, influencing climate. This study explores BrC's imaginary refractive index (k) using data from 12 European sites. Residential emissions are a major organic aerosol (OA) source in winter, while secondary organic aerosol (SOA) dominates in summer. Source-specific k values were derived, improving model accuracy. The findings highlight BrC's climate impact and emphasize source-specific constraints in atmospheric models.
Ryan Vella, Matthew Forrest, Andrea Pozzer, Alexandra P. Tsimpidi, Thomas Hickler, Jos Lelieveld, and Holger Tost
Atmos. Chem. Phys., 25, 243–262, https://doi.org/10.5194/acp-25-243-2025, https://doi.org/10.5194/acp-25-243-2025, 2025
Short summary
Short summary
This study examines how land cover changes influence biogenic volatile organic compound (BVOC) emissions and atmospheric states. Using a coupled chemistry–climate–vegetation model, we compare present-day land cover (deforested for crops and grazing) with natural vegetation and an extreme reforestation scenario. We find that vegetation changes significantly impact global BVOC emissions and organic aerosols but have a relatively small effect on total aerosols, clouds, and radiative effects.
Leon Kuhn, Steffen Beirle, Sergey Osipov, Andrea Pozzer, and Thomas Wagner
Atmos. Meas. Tech., 17, 6485–6516, https://doi.org/10.5194/amt-17-6485-2024, https://doi.org/10.5194/amt-17-6485-2024, 2024
Short summary
Short summary
This paper presents a new machine learning model that allows us to compute NO2 concentration profiles from satellite observations. A neural network was trained on synthetic data from the regional chemistry and transport model WRF-Chem. This is the first model of its kind. We present a thorough model validation study, covering various seasons and regions of the world.
Akima Ringsdorf, Achim Edtbauer, Bruna Holanda, Christopher Poehlker, Marta O. Sá, Alessandro Araújo, Jürgen Kesselmeier, Jos Lelieveld, and Jonathan Williams
Atmos. Chem. Phys., 24, 11883–11910, https://doi.org/10.5194/acp-24-11883-2024, https://doi.org/10.5194/acp-24-11883-2024, 2024
Short summary
Short summary
We show the average height distribution of separately observed aldehydes and ketones over a day and discuss their rainforest-specific sources and sinks as well as their seasonal changes above the Amazon. Ketones have much longer atmospheric lifetimes than aldehydes and thus different implications for atmospheric chemistry. However, they are commonly observed together, which we overcome by measuring with a NO+ chemical ionization mass spectrometer for the first time in the Amazon rainforest.
Simone T. Andersen, Max R. McGillen, Chaoyang Xue, Tobias Seubert, Patrick Dewald, Gunther N. T. E. Türk, Jan Schuladen, Cyrielle Denjean, Jean-Claude Etienne, Olivier Garrouste, Marina Jamar, Sergio Harb, Manuela Cirtog, Vincent Michoud, Mathieu Cazaunau, Antonin Bergé, Christopher Cantrell, Sebastien Dusanter, Bénédicte Picquet-Varrault, Alexandre Kukui, Abdelwahid Mellouki, Lucy J. Carpenter, Jos Lelieveld, and John N. Crowley
Atmos. Chem. Phys., 24, 11603–11618, https://doi.org/10.5194/acp-24-11603-2024, https://doi.org/10.5194/acp-24-11603-2024, 2024
Short summary
Short summary
Using measurements of various trace gases in a suburban forest near Paris in the summer of 2022, we were able to gain insight into the sources and sinks of NOx (NO+NO2) with a special focus on their nighttime chemical and physical loss processes. NO was observed as a result of nighttime soil emissions when O3 levels were strongly depleted by deposition. NO oxidation products were not observed at night, indicating that soil and/or foliar surfaces are an efficient sink of reactive N.
Patrick Dewald, Tobias Seubert, Simone T. Andersen, Gunther N. T. E. Türk, Jan Schuladen, Max R. McGillen, Cyrielle Denjean, Jean-Claude Etienne, Olivier Garrouste, Marina Jamar, Sergio Harb, Manuela Cirtog, Vincent Michoud, Mathieu Cazaunau, Antonin Bergé, Christopher Cantrell, Sebastien Dusanter, Bénédicte Picquet-Varrault, Alexandre Kukui, Chaoyang Xue, Abdelwahid Mellouki, Jos Lelieveld, and John N. Crowley
Atmos. Chem. Phys., 24, 8983–8997, https://doi.org/10.5194/acp-24-8983-2024, https://doi.org/10.5194/acp-24-8983-2024, 2024
Short summary
Short summary
In the scope of a field campaign in a suburban forest near Paris in the summer of 2022, we measured the reactivity of the nitrate radical NO3 towards biogenic volatile organic compounds (BVOCs; e.g. monoterpenes) mainly below but also above the canopy. NO3 reactivity was the highest during nights with strong temperature inversions and decreased strongly with height. Reactions with BVOCs were the main removal process of NO3 throughout the diel cycle below the canopy.
Luiz A. T. Machado, Jürgen Kesselmeier, Santiago Botía, Hella van Asperen, Meinrat O. Andreae, Alessandro C. de Araújo, Paulo Artaxo, Achim Edtbauer, Rosaria R. Ferreira, Marco A. Franco, Hartwig Harder, Sam P. Jones, Cléo Q. Dias-Júnior, Guido G. Haytzmann, Carlos A. Quesada, Shujiro Komiya, Jost Lavric, Jos Lelieveld, Ingeborg Levin, Anke Nölscher, Eva Pfannerstill, Mira L. Pöhlker, Ulrich Pöschl, Akima Ringsdorf, Luciana Rizzo, Ana M. Yáñez-Serrano, Susan Trumbore, Wanda I. D. Valenti, Jordi Vila-Guerau de Arellano, David Walter, Jonathan Williams, Stefan Wolff, and Christopher Pöhlker
Atmos. Chem. Phys., 24, 8893–8910, https://doi.org/10.5194/acp-24-8893-2024, https://doi.org/10.5194/acp-24-8893-2024, 2024
Short summary
Short summary
Composite analysis of gas concentration before and after rainfall, during the day and night, gives insight into the complex relationship between trace gas variability and precipitation. The analysis helps us to understand the sources and sinks of trace gases within a forest ecosystem. It elucidates processes that are not discernible under undisturbed conditions and contributes to a deeper understanding of the trace gas life cycle and its intricate interactions with cloud dynamics in the Amazon.
Pantelis Georgiades, Matthias Kohl, Mihalis A. Nicolaou, Theodoros Christoudias, Andrea Pozzer, Constantine Dovrolis, and Jos Lelieveld
Earth Syst. Sci. Data Discuss., https://doi.org/10.5194/essd-2024-314, https://doi.org/10.5194/essd-2024-314, 2024
Manuscript not accepted for further review
Short summary
Short summary
This study maps global ultrafine particle (UFP) concentrations, pollutants known to affect health, using machine learning. By combining environmental and urban data, we predicted UFP levels at a fine 1 km resolution, highlighting areas of high exposure. Our results provide data for public health policies aimed at reducing air pollution impacts. This research bridges data gaps, offering a valuable tool for understanding and mitigating the health effects of UFP exposure.
Matthias Nützel, Laura Stecher, Patrick Jöckel, Franziska Winterstein, Martin Dameris, Michael Ponater, Phoebe Graf, and Markus Kunze
Geosci. Model Dev., 17, 5821–5849, https://doi.org/10.5194/gmd-17-5821-2024, https://doi.org/10.5194/gmd-17-5821-2024, 2024
Short summary
Short summary
We extended the infrastructure of our modelling system to enable the use of an additional radiation scheme. After calibrating the model setups to the old and the new radiation scheme, we find that the simulation with the new scheme shows considerable improvements, e.g. concerning the cold-point temperature and stratospheric water vapour. Furthermore, perturbations of radiative fluxes associated with greenhouse gas changes, e.g. of methane, tend to be improved when the new scheme is employed.
Anna Martin, Veronika Gayler, Benedikt Steil, Klaus Klingmüller, Patrick Jöckel, Holger Tost, Jos Lelieveld, and Andrea Pozzer
Geosci. Model Dev., 17, 5705–5732, https://doi.org/10.5194/gmd-17-5705-2024, https://doi.org/10.5194/gmd-17-5705-2024, 2024
Short summary
Short summary
The study evaluates the land surface and vegetation model JSBACHv4 as a replacement for the simplified submodel SURFACE in EMAC. JSBACH mitigates earlier problems of soil dryness, which are critical for vegetation modelling. When analysed using different datasets, the coupled model shows strong correlations of key variables, such as land surface temperature, surface albedo and radiation flux. The versatility of the model increases significantly, while the overall performance does not degrade.
Georgia Lazoglou, Theo Economou, Christina Anagnostopoulou, George Zittis, Anna Tzyrkalli, Pantelis Georgiades, and Jos Lelieveld
Geosci. Model Dev., 17, 4689–4703, https://doi.org/10.5194/gmd-17-4689-2024, https://doi.org/10.5194/gmd-17-4689-2024, 2024
Short summary
Short summary
This study focuses on the important issue of the drizzle bias effect in regional climate models, described by an over-prediction of the number of rainy days while underestimating associated precipitation amounts. For this purpose, two distinct methodologies are applied and rigorously evaluated. These results are encouraging for using the multivariate machine learning method random forest to increase the accuracy of climate models concerning the projection of the number of wet days.
Linda Ort, Lenard Lukas Röder, Uwe Parchatka, Rainer Königstedt, Daniel Crowley, Frank Kunz, Ralf Wittkowski, Jos Lelieveld, and Horst Fischer
Atmos. Meas. Tech., 17, 3553–3565, https://doi.org/10.5194/amt-17-3553-2024, https://doi.org/10.5194/amt-17-3553-2024, 2024
Short summary
Short summary
Airborne in situ measurements are of great importance to collect valuable data to improve our knowledge of the atmosphere but also present challenges which demand specific designs. This study presents an IR spectrometer for airborne trace-gas measurements with high data efficiency and a simple, compact design. Its in-flight performance is characterized with the help of a test flight and a comparison with another spectrometer. Moreover, results from its first campaign highlight its benefits.
Edward Groot, Patrick Kuntze, Annette Miltenberger, and Holger Tost
Weather Clim. Dynam., 5, 779–803, https://doi.org/10.5194/wcd-5-779-2024, https://doi.org/10.5194/wcd-5-779-2024, 2024
Short summary
Short summary
Deep convective clouds (thunderstorms), which may cause severe weather, tend to coherently organise into structured cloud systems. Accurate representation of these systems in models is difficult due to their complex dynamics and, in numerical simulations, the dependence of their dynamics on resolution. Here, the effect of convective organisation and geometry on their outflow winds (altitudes of 7–14 km) is investigated. Representation of their dynamics and outflows improves at higher resolution.
Simon Rosanka, Holger Tost, Rolf Sander, Patrick Jöckel, Astrid Kerkweg, and Domenico Taraborrelli
Geosci. Model Dev., 17, 2597–2615, https://doi.org/10.5194/gmd-17-2597-2024, https://doi.org/10.5194/gmd-17-2597-2024, 2024
Short summary
Short summary
The capabilities of the Modular Earth Submodel System (MESSy) are extended to account for non-equilibrium aqueous-phase chemistry in the representation of deliquescent aerosols. When applying the new development in a global simulation, we find that MESSy's bias in modelling routinely observed reduced inorganic aerosol mass concentrations, especially in the United States. Furthermore, the representation of fine-aerosol pH is particularly improved in the marine boundary layer.
Simone Rodrigues, Glauber Cirino, Demerval Moreira, Andrea Pozzer, Rafael Palácios, Sung-Ching Lee, Breno Imbiriba, José Nogueira, Maria Isabel Vitorino, and George Vourlitis
Biogeosciences, 21, 843–868, https://doi.org/10.5194/bg-21-843-2024, https://doi.org/10.5194/bg-21-843-2024, 2024
Short summary
Short summary
The radiative effects of atmospheric particles are still unknown for a wide variety of species and types of vegetation present in Amazonian biomes. We examined the effects of aerosols on solar radiation and their impacts on photosynthesis in an area of semideciduous forest in the southern Amazon Basin. Under highly smoky-sky conditions, our results show substantial photosynthetic interruption (20–70 %), attributed specifically to the decrease in solar radiation and leaf canopy temperature.
Imran A. Girach, Narendra Ojha, Prabha R. Nair, Kandula V. Subrahmanyam, Neelakantan Koushik, Mohammed M. Nazeer, Nadimpally Kiran Kumar, Surendran Nair Suresh Babu, Jos Lelieveld, and Andrea Pozzer
Atmos. Chem. Phys., 24, 1979–1995, https://doi.org/10.5194/acp-24-1979-2024, https://doi.org/10.5194/acp-24-1979-2024, 2024
Short summary
Short summary
We investigate surface ozone variability in East Antarctica based on measurements and EMAC global model simulations during austral summer. Nearly half of the surface ozone is found to be of stratospheric origin. The east coast of Antarctica acts as a stronger sink of ozone than surrounding regions. Photochemical loss of ozone is counterbalanced by downward transport of ozone. The study highlights the intertwined role of chemistry and dynamics in governing ozone variations over East Antarctica.
Sarah Brüning, Stefan Niebler, and Holger Tost
Atmos. Meas. Tech., 17, 961–978, https://doi.org/10.5194/amt-17-961-2024, https://doi.org/10.5194/amt-17-961-2024, 2024
Short summary
Short summary
We apply the Res-UNet to derive a comprehensive 3D cloud tomography from 2D satellite data over heterogeneous landscapes. We combine observational data from passive and active remote sensing sensors by an automated matching algorithm. These data are fed into a neural network to predict cloud reflectivities on the whole satellite domain between 2.4 and 24 km height. With an average RMSE of 2.99 dBZ, we contribute to closing data gaps in the representation of clouds in observational data.
Leon Kuhn, Steffen Beirle, Vinod Kumar, Sergey Osipov, Andrea Pozzer, Tim Bösch, Rajesh Kumar, and Thomas Wagner
Atmos. Chem. Phys., 24, 185–217, https://doi.org/10.5194/acp-24-185-2024, https://doi.org/10.5194/acp-24-185-2024, 2024
Short summary
Short summary
NO₂ is an important air pollutant. It was observed that the WRF-Chem model shows significant deviations in NO₂ abundance when compared to measurements. We use a 1-month simulation over central Europe to show that these deviations can be mostly resolved by reparameterization of the vertical mixing routine. In order to validate our results, they are compared to in situ, satellite, and MAX-DOAS measurements.
Meghna Soni, Rolf Sander, Lokesh K. Sahu, Domenico Taraborrelli, Pengfei Liu, Ankit Patel, Imran A. Girach, Andrea Pozzer, Sachin S. Gunthe, and Narendra Ojha
Atmos. Chem. Phys., 23, 15165–15180, https://doi.org/10.5194/acp-23-15165-2023, https://doi.org/10.5194/acp-23-15165-2023, 2023
Short summary
Short summary
The study presents the implementation of comprehensive multiphase chlorine chemistry in the box model CAABA/MECCA. Simulations for contrasting urban environments of Asia and Europe highlight the significant impacts of chlorine on atmospheric oxidation capacity and composition. Chemical processes governing the production and loss of chlorine-containing species has been discussed. The updated chemical mechanism will be useful to interpret field measurements and for future air quality studies.
Ryan Vella, Andrea Pozzer, Matthew Forrest, Jos Lelieveld, Thomas Hickler, and Holger Tost
Biogeosciences, 20, 4391–4412, https://doi.org/10.5194/bg-20-4391-2023, https://doi.org/10.5194/bg-20-4391-2023, 2023
Short summary
Short summary
We investigated the effect of the El Niño–Southern Oscillation (ENSO) on biogenic volatile organic compound (BVOC) emissions from plants. ENSO events can cause a significant increase in these emissions, which have a long-term impact on the Earth's atmosphere. Persistent ENSO conditions can cause long-term changes in vegetation, resulting in even higher BVOC emissions. We link ENSO-induced emission anomalies with driving atmospheric and vegetational variables.
Susanna Strada, Andrea Pozzer, Graziano Giuliani, Erika Coppola, Fabien Solmon, Xiaoyan Jiang, Alex Guenther, Efstratios Bourtsoukidis, Dominique Serça, Jonathan Williams, and Filippo Giorgi
Atmos. Chem. Phys., 23, 13301–13327, https://doi.org/10.5194/acp-23-13301-2023, https://doi.org/10.5194/acp-23-13301-2023, 2023
Short summary
Short summary
Water deficit modifies emissions of isoprene, an aromatic compound released by plants that influences the production of an air pollutant such as ozone. Numerical modelling shows that, during the warmest and driest summers, isoprene decreases between −20 and −60 % over the Euro-Mediterranean region, while near-surface ozone only diminishes by a few percent. Decreases in isoprene emissions not only happen under dry conditions, but also could occur after prolonged or repeated water deficits.
Zaneta Hamryszczak, Antonia Hartmann, Dirk Dienhart, Sascha Hafermann, Bettina Brendel, Rainer Königstedt, Uwe Parchatka, Jos Lelieveld, and Horst Fischer
Atmos. Meas. Tech., 16, 4741–4756, https://doi.org/10.5194/amt-16-4741-2023, https://doi.org/10.5194/amt-16-4741-2023, 2023
Short summary
Short summary
Hydroperoxide measurements improve the understanding of atmospheric oxidation processes. We introduce an instrumental setup for airborne measurements. The aim of the work is the characterization of the measurement method with emphasis on interferences impacting instrumental uncertainty. Technical and physical challenges do not critically impact the instrumental performance. The instrument resolves dynamic processes, such as convective transport, as shown based on the CAFE-Brazil campaign.
Matthias Kohl, Jos Lelieveld, Sourangsu Chowdhury, Sebastian Ehrhart, Disha Sharma, Yafang Cheng, Sachchida Nand Tripathi, Mathew Sebastian, Govindan Pandithurai, Hongli Wang, and Andrea Pozzer
Atmos. Chem. Phys., 23, 13191–13215, https://doi.org/10.5194/acp-23-13191-2023, https://doi.org/10.5194/acp-23-13191-2023, 2023
Short summary
Short summary
Knowledge on atmospheric ultrafine particles (UFPs) with a diameter smaller than 100 nm is crucial for public health and the hydrological cycle. We present a new global dataset of UFP concentrations at the Earth's surface derived with a comprehensive chemistry–climate model and evaluated with ground-based observations. The evaluation results are combined with high-resolution primary emissions to downscale UFP concentrations to an unprecedented horizontal resolution of 0.1° × 0.1°.
Clara M. Nussbaumer, Bryan K. Place, Qindan Zhu, Eva Y. Pfannerstill, Paul Wooldridge, Benjamin C. Schulze, Caleb Arata, Ryan Ward, Anthony Bucholtz, John H. Seinfeld, Allen H. Goldstein, and Ronald C. Cohen
Atmos. Chem. Phys., 23, 13015–13028, https://doi.org/10.5194/acp-23-13015-2023, https://doi.org/10.5194/acp-23-13015-2023, 2023
Short summary
Short summary
NOx is a precursor to hazardous tropospheric ozone and can be emitted from various anthropogenic sources. It is important to quantify NOx emissions in urban environments to improve the local air quality, which still remains a challenge, as sources are heterogeneous in space and time. In this study, we calculate NOx emissions over Los Angeles, based on aircraft measurements in June 2021, and compare them to a local emission inventory, which we find mostly overpredicts the measured values.
Clara M. Nussbaumer, Horst Fischer, Jos Lelieveld, and Andrea Pozzer
Atmos. Chem. Phys., 23, 12651–12669, https://doi.org/10.5194/acp-23-12651-2023, https://doi.org/10.5194/acp-23-12651-2023, 2023
Short summary
Short summary
Ozone is a greenhouse gas and contributes to the earth’s radiative energy budget and therefore to global warming. This effect is the largest in the upper troposphere. In this study, we investigate the processes controlling ozone formation and the sensitivity to its precursors in the upper tropical troposphere based on model simulations by the ECHAM5/MESSy2 Atmospheric Chemistry (EMAC) model. We find that NO𝑥 emissions from lightning most importantly affect ozone chemistry at these altitudes.
Qindan Zhu, Bryan Place, Eva Y. Pfannerstill, Sha Tong, Huanxin Zhang, Jun Wang, Clara M. Nussbaumer, Paul Wooldridge, Benjamin C. Schulze, Caleb Arata, Anthony Bucholtz, John H. Seinfeld, Allen H. Goldstein, and Ronald C. Cohen
Atmos. Chem. Phys., 23, 9669–9683, https://doi.org/10.5194/acp-23-9669-2023, https://doi.org/10.5194/acp-23-9669-2023, 2023
Short summary
Short summary
Nitrogen oxide (NOx) is a hazardous air pollutant, and it is the precursor of short-lived climate forcers like tropospheric ozone and aerosol particles. While NOx emissions from transportation has been strictly regulated, soil NOx emissions are overlooked. We use the airborne flux measurements to observe NOx emissions from highways and urban and cultivated soil land cover types. We show non-negligible soil NOx emissions, which are significantly underestimated in current model simulations.
Seyed Omid Nabavi, Theodoros Christoudias, Yiannis Proestos, Christos Fountoukis, Huda Al-Sulaiti, and Jos Lelieveld
Atmos. Chem. Phys., 23, 7719–7739, https://doi.org/10.5194/acp-23-7719-2023, https://doi.org/10.5194/acp-23-7719-2023, 2023
Short summary
Short summary
The objective of our study is to comprehensively assess the timing of radioactive material transportation and deposition, along with the associated population exposure in the designated region. We employed diverse meteorological inputs, emission specifics, and simulation codes, aiming to quantify the level of uncertainty.
Edward Groot and Holger Tost
Atmos. Chem. Phys., 23, 6065–6081, https://doi.org/10.5194/acp-23-6065-2023, https://doi.org/10.5194/acp-23-6065-2023, 2023
Short summary
Short summary
It is shown that the outflow from cumulonimbus clouds or thunderstorms in the upper troposphere and lower stratosphere in idealized high-resolution simulations (LESs) depends linearly on the net amount of latent heat released by the cloud for fixed geometry of the clouds. However, it is shown that, in more realistic situations, convective organization and aggregation (collecting mechanisms of cumulonimbus clouds) affect the amount of outflow non-linearly through non-idealized geometry.
Thomas Kleinen, Sergey Gromov, Benedikt Steil, and Victor Brovkin
Clim. Past, 19, 1081–1099, https://doi.org/10.5194/cp-19-1081-2023, https://doi.org/10.5194/cp-19-1081-2023, 2023
Short summary
Short summary
We modelled atmospheric methane continuously from the last glacial maximum to the present using a state-of-the-art Earth system model. Our model results compare well with reconstructions from ice cores and improve our understanding of a very intriguing period of Earth system history, the deglaciation, when atmospheric methane changed quickly and strongly. Deglacial methane changes are driven by emissions from tropical wetlands, with wetlands in high northern latitudes being secondary.
Klaus Klingmüller and Jos Lelieveld
Geosci. Model Dev., 16, 3013–3028, https://doi.org/10.5194/gmd-16-3013-2023, https://doi.org/10.5194/gmd-16-3013-2023, 2023
Short summary
Short summary
Desert dust has significant impacts on climate, public health, infrastructure and ecosystems. An impact assessment requires numerical predictions, which are challenging because the dust emissions are not well known. We present a novel approach using satellite observations and machine learning to more accurately estimate the emissions and to improve the model simulations.
Zaneta Hamryszczak, Dirk Dienhart, Bettina Brendel, Roland Rohloff, Daniel Marno, Monica Martinez, Hartwig Harder, Andrea Pozzer, Birger Bohn, Martin Zöger, Jos Lelieveld, and Horst Fischer
Atmos. Chem. Phys., 23, 5929–5943, https://doi.org/10.5194/acp-23-5929-2023, https://doi.org/10.5194/acp-23-5929-2023, 2023
Short summary
Short summary
Hydrogen peroxide is a key contributor to the oxidative chemistry of the atmosphere through its link to the most prominent oxidants controlling its self-cleansing capacity, HOx. During the CAFE-Africa campaign, H2O2 was measured over the Atlantic Ocean and western Africa in August/September 2018. The study gives an overview of the distribution of H2O2 in the upper tropical troposphere and investigates the impact of convective processes in the Intertropical Convergence Zone on the budget of H2O2.
Lenard L. Röder, Patrick Dewald, Clara M. Nussbaumer, Jan Schuladen, John N. Crowley, Jos Lelieveld, and Horst Fischer
Atmos. Meas. Tech., 16, 1167–1178, https://doi.org/10.5194/amt-16-1167-2023, https://doi.org/10.5194/amt-16-1167-2023, 2023
Short summary
Short summary
Field experiments in atmospheric chemistry provide insights into chemical interactions of our atmosphere. However, high data coverage and accuracy are needed to enable further analysis. In this study, we explore a statistical method that combines knowledge about the chemical reactions with information from measurements to increase the quality of field experiment datasets. We test the algorithm for several applications and discuss limitations that depend on the specific variable and the dynamics.
Ryan Vella, Matthew Forrest, Jos Lelieveld, and Holger Tost
Geosci. Model Dev., 16, 885–906, https://doi.org/10.5194/gmd-16-885-2023, https://doi.org/10.5194/gmd-16-885-2023, 2023
Short summary
Short summary
Biogenic volatile organic compounds (BVOCs) are released by vegetation and have a major impact on atmospheric chemistry and aerosol formation. Non-interacting vegetation constrains the majority of numerical models used to estimate global BVOC emissions, and thus, the effects of changing vegetation on emissions are not addressed. In this work, we replace the offline vegetation with dynamic vegetation states by linking a chemistry–climate model with a global dynamic vegetation model.
Jennifer Schallock, Christoph Brühl, Christine Bingen, Michael Höpfner, Landon Rieger, and Jos Lelieveld
Atmos. Chem. Phys., 23, 1169–1207, https://doi.org/10.5194/acp-23-1169-2023, https://doi.org/10.5194/acp-23-1169-2023, 2023
Short summary
Short summary
We characterized the influence of volcanic aerosols for the period 1990–2019 and established a volcanic SO2 emission inventory that includes more than 500 eruptions. From limb-based satellite observations of SO2 and extinction, we derive 3D plumes of SO2 perturbations and injected mass by a novel method. We calculate instantaneous radiative forcing with a comprehensive chemisty climate model. Our results show that smaller eruptions can also contribute to the stratospheric aerosol forcing.
Edward Groot and Holger Tost
Atmos. Chem. Phys., 23, 565–585, https://doi.org/10.5194/acp-23-565-2023, https://doi.org/10.5194/acp-23-565-2023, 2023
Short summary
Short summary
Thunderstorm systems play an important role in the dynamics of the Earth’s atmosphere, and some of them form a well-organised line: squall lines. Simulations of such squall lines with very small initial perturbations are compared to a reference simulation. The evolution of perturbations and processes amplifying them are analysed. It is shown that the formation of new secondary thunderstorm cells (after the initial primary cells) directly ahead of the line affects the spread strongly.
Mohamed Abdelkader, Georgiy Stenchikov, Andrea Pozzer, Holger Tost, and Jos Lelieveld
Atmos. Chem. Phys., 23, 471–500, https://doi.org/10.5194/acp-23-471-2023, https://doi.org/10.5194/acp-23-471-2023, 2023
Short summary
Short summary
We study the effect of injected volcanic ash, water vapor, and SO2 on the development of the volcanic cloud and the stratospheric aerosol optical depth (AOD). Both are sensitive to the initial injection height and to the aging of the volcanic ash shaped by heterogeneous chemistry coupled with the ozone cycle. The paper explains the large differences in AOD for different injection scenarios, which could improve the estimate of the radiative forcing of volcanic eruptions.
Dirk Dienhart, Bettina Brendel, John N. Crowley, Philipp G. Eger, Hartwig Harder, Monica Martinez, Andrea Pozzer, Roland Rohloff, Jan Schuladen, Sebastian Tauer, David Walter, Jos Lelieveld, and Horst Fischer
Atmos. Chem. Phys., 23, 119–142, https://doi.org/10.5194/acp-23-119-2023, https://doi.org/10.5194/acp-23-119-2023, 2023
Short summary
Short summary
Formaldehyde and hydroperoxide measurements were performed in the marine boundary layer around the Arabian Peninsula and highlight the Suez Canal and Arabian (Persian) Gulf as a hotspot of photochemical air pollution. A comparison with the EMAC model shows that the formaldehyde results match within a factor of 2, while hydrogen peroxide was overestimated by more than a factor of 5, which revealed enhanced HOx (OH+HO2) radicals in the simulation and an underestimation of dry deposition velocites.
Laura Tomsche, Andreas Marsing, Tina Jurkat-Witschas, Johannes Lucke, Stefan Kaufmann, Katharina Kaiser, Johannes Schneider, Monika Scheibe, Hans Schlager, Lenard Röder, Horst Fischer, Florian Obersteiner, Andreas Zahn, Martin Zöger, Jos Lelieveld, and Christiane Voigt
Atmos. Chem. Phys., 22, 15135–15151, https://doi.org/10.5194/acp-22-15135-2022, https://doi.org/10.5194/acp-22-15135-2022, 2022
Short summary
Short summary
The detection of sulfur compounds in the upper troposphere (UT) and lower stratosphere (LS) is a challenge. In-flight measurements of SO2 and sulfate aerosol were performed during the BLUESKY mission in spring 2020 under exceptional atmospheric conditions. Reduced sinks in the dry UTLS and lower but still significant air traffic influenced the enhanced SO2 in the UT, and aged volcanic plumes enhanced the LS sulfate aerosol impacting the atmospheric radiation budget and global climate.
Charlotte M. Beall, Thomas C. J. Hill, Paul J. DeMott, Tobias Köneman, Michael Pikridas, Frank Drewnick, Hartwig Harder, Christopher Pöhlker, Jos Lelieveld, Bettina Weber, Minas Iakovides, Roman Prokeš, Jean Sciare, Meinrat O. Andreae, M. Dale Stokes, and Kimberly A. Prather
Atmos. Chem. Phys., 22, 12607–12627, https://doi.org/10.5194/acp-22-12607-2022, https://doi.org/10.5194/acp-22-12607-2022, 2022
Short summary
Short summary
Ice-nucleating particles (INPs) are rare aerosols that can trigger ice formation in clouds and affect climate-relevant cloud properties such as phase, reflectivity and lifetime. Dust is the dominant INP source, yet few measurements have been reported near major dust sources. We report INP observations within hundreds of kilometers of the biggest dust source regions globally: the Sahara and the Arabian Peninsula. Results show that at temperatures > −15 °C, INPs are dominated by organics.
Mengze Li, Andrea Pozzer, Jos Lelieveld, and Jonathan Williams
Earth Syst. Sci. Data, 14, 4351–4364, https://doi.org/10.5194/essd-14-4351-2022, https://doi.org/10.5194/essd-14-4351-2022, 2022
Short summary
Short summary
We present a northern hemispheric airborne measurement dataset of atmospheric ethane, propane and methane and temporal trends for the time period 2006–2016 in the upper troposphere and lower stratosphere. The growth rates of ethane, methane, and propane in the upper troposphere are -2.24, 0.33, and -0.78 % yr-1, respectively, and in the lower stratosphere they are -3.27, 0.26, and -4.91 % yr-1, respectively, in 2006–2016.
Simon F. Reifenberg, Anna Martin, Matthias Kohl, Sara Bacer, Zaneta Hamryszczak, Ivan Tadic, Lenard Röder, Daniel J. Crowley, Horst Fischer, Katharina Kaiser, Johannes Schneider, Raphael Dörich, John N. Crowley, Laura Tomsche, Andreas Marsing, Christiane Voigt, Andreas Zahn, Christopher Pöhlker, Bruna A. Holanda, Ovid Krüger, Ulrich Pöschl, Mira Pöhlker, Patrick Jöckel, Marcel Dorf, Ulrich Schumann, Jonathan Williams, Birger Bohn, Joachim Curtius, Hardwig Harder, Hans Schlager, Jos Lelieveld, and Andrea Pozzer
Atmos. Chem. Phys., 22, 10901–10917, https://doi.org/10.5194/acp-22-10901-2022, https://doi.org/10.5194/acp-22-10901-2022, 2022
Short summary
Short summary
In this work we use a combination of observational data from an aircraft campaign and model results to investigate the effect of the European lockdown due to COVID-19 in spring 2020. Using model results, we show that the largest relative changes to the atmospheric composition caused by the reduced emissions are located in the upper troposphere around aircraft cruise altitude, while the largest absolute changes are present at the surface.
Zaneta T. Hamryszczak, Andrea Pozzer, Florian Obersteiner, Birger Bohn, Benedikt Steil, Jos Lelieveld, and Horst Fischer
Atmos. Chem. Phys., 22, 9483–9497, https://doi.org/10.5194/acp-22-9483-2022, https://doi.org/10.5194/acp-22-9483-2022, 2022
Short summary
Short summary
Hydrogen peroxide plays a pivotal role in the chemistry of the atmosphere. Together with organic hydroperoxides, it forms a reservoir for peroxy radicals, which are known to be the key contributors to the self-cleaning processes of the atmosphere. Hydroperoxides were measured over Europe during the BLUESKY campaign in May–June 2020. The paper gives an overview of the distribution of the species in the troposphere and investigates the impact of wet scavenging and deposition on the budget of H2O2.
Marco Wietzoreck, Marios Kyprianou, Benjamin A. Musa Bandowe, Siddika Celik, John N. Crowley, Frank Drewnick, Philipp Eger, Nils Friedrich, Minas Iakovides, Petr Kukučka, Jan Kuta, Barbora Nežiková, Petra Pokorná, Petra Přibylová, Roman Prokeš, Roland Rohloff, Ivan Tadic, Sebastian Tauer, Jake Wilson, Hartwig Harder, Jos Lelieveld, Ulrich Pöschl, Euripides G. Stephanou, and Gerhard Lammel
Atmos. Chem. Phys., 22, 8739–8766, https://doi.org/10.5194/acp-22-8739-2022, https://doi.org/10.5194/acp-22-8739-2022, 2022
Short summary
Short summary
A unique dataset of concentrations and sources of polycyclic aromatic hydrocarbons (PAHs) and their alkylated, oxygenated and nitrated derivatives, in total 74 individual species, in the marine atmosphere is presented. Exposure to these substances poses a major health risk. We found very low concentrations over the Arabian Sea, while both local and long-range-transported pollution caused elevated levels over the Mediterranean Sea and the Arabian Gulf.
Ovid O. Krüger, Bruna A. Holanda, Sourangsu Chowdhury, Andrea Pozzer, David Walter, Christopher Pöhlker, Maria Dolores Andrés Hernández, John P. Burrows, Christiane Voigt, Jos Lelieveld, Johannes Quaas, Ulrich Pöschl, and Mira L. Pöhlker
Atmos. Chem. Phys., 22, 8683–8699, https://doi.org/10.5194/acp-22-8683-2022, https://doi.org/10.5194/acp-22-8683-2022, 2022
Short summary
Short summary
The abrupt reduction in human activities during the first COVID-19 lockdown created unprecedented atmospheric conditions. We took the opportunity to quantify changes in black carbon (BC) as a major anthropogenic air pollutant. Therefore, we measured BC on board a research aircraft over Europe during the lockdown and compared the results to measurements from 2017. With model simulations we account for different weather conditions and find a lockdown-related decrease in BC of 41 %.
Patrick Dewald, Clara M. Nussbaumer, Jan Schuladen, Akima Ringsdorf, Achim Edtbauer, Horst Fischer, Jonathan Williams, Jos Lelieveld, and John N. Crowley
Atmos. Chem. Phys., 22, 7051–7069, https://doi.org/10.5194/acp-22-7051-2022, https://doi.org/10.5194/acp-22-7051-2022, 2022
Short summary
Short summary
We measured the gas-phase reactivity of the NO3 radical on the summit (825 m a.s.l.) of a semi-rural mountain in southwestern Germany in July 2021. The impact of VOC-induced NO3 losses (mostly monoterpenes) competing with a loss by reaction with NO and photolysis throughout the diel cycle was estimated. Besides chemistry, boundary layer dynamics and plant-physiological processes presumably have a great impact on our observations, which were compared to previous NO3 measurements at the same site.
George K. Georgiou, Theodoros Christoudias, Yiannis Proestos, Jonilda Kushta, Michael Pikridas, Jean Sciare, Chrysanthos Savvides, and Jos Lelieveld
Geosci. Model Dev., 15, 4129–4146, https://doi.org/10.5194/gmd-15-4129-2022, https://doi.org/10.5194/gmd-15-4129-2022, 2022
Short summary
Short summary
We evaluate the skill of the WRF-Chem model to perform high-resolution air quality forecasts (including ozone, nitrogen dioxide, and fine particulate matter) over the Eastern Mediterranean, during winter and summer. We compare the forecast output to observational data from background and urban locations and the forecast output from CAMS. WRF-Chem was found to forecast the concentrations and diurnal profiles of gas-phase pollutants in urban areas with higher accuracy.
Dimitris Akritidis, Andrea Pozzer, Johannes Flemming, Antje Inness, Philippe Nédélec, and Prodromos Zanis
Atmos. Chem. Phys., 22, 6275–6289, https://doi.org/10.5194/acp-22-6275-2022, https://doi.org/10.5194/acp-22-6275-2022, 2022
Short summary
Short summary
We perform a process-oriented evaluation of Copernicus Atmosphere Monitoring Service (CAMS) reanalysis (CAMSRA) O3 over Europe using WOUDC (World Ozone and Ultraviolet Radiation Data Centre) ozonesondes and IAGOS (In-service Aircraft for a Global Observing System) aircraft measurements. Chemical data assimilation assists CAMSRA to reproduce the observed O3 increases in the troposphere during the examined folding events, but it mostly results in O3 overestimation in the upper troposphere.
Clara M. Nussbaumer, Andrea Pozzer, Ivan Tadic, Lenard Röder, Florian Obersteiner, Hartwig Harder, Jos Lelieveld, and Horst Fischer
Atmos. Chem. Phys., 22, 6151–6165, https://doi.org/10.5194/acp-22-6151-2022, https://doi.org/10.5194/acp-22-6151-2022, 2022
Short summary
Short summary
The European COVID-19 lockdowns have significantly reduced the emission of primary pollutants such as NOx, which impacts the tropospheric photochemical processes and the abundance of O3. In this study, we present how the lockdowns have affected tropospheric trace gases and ozone production based on in situ observations and modeling simulations. We additionally show that the chemical regime shifted from a transition point to a NOx limitation in the upper troposphere.
Wenyu Sun, Matias Berasategui, Andrea Pozzer, Jos Lelieveld, and John N. Crowley
Atmos. Chem. Phys., 22, 4969–4984, https://doi.org/10.5194/acp-22-4969-2022, https://doi.org/10.5194/acp-22-4969-2022, 2022
Short summary
Short summary
The reaction between OH and SO2 is a termolecular process that in the atmosphere results in the formation of H2SO4 and thus aerosols. We present the first temperature- and pressure-dependent measurements of the rate coefficients in N2. This is also the first study to examine the effects of water vapour on the kinetics of this reaction. Our results indicate the rate coefficient is larger than that recommended by evaluation panels, with deviations of up to 30 % in some parts of the atmosphere.
Andrea Pozzer, Simon F. Reifenberg, Vinod Kumar, Bruno Franco, Matthias Kohl, Domenico Taraborrelli, Sergey Gromov, Sebastian Ehrhart, Patrick Jöckel, Rolf Sander, Veronica Fall, Simon Rosanka, Vlassis Karydis, Dimitris Akritidis, Tamara Emmerichs, Monica Crippa, Diego Guizzardi, Johannes W. Kaiser, Lieven Clarisse, Astrid Kiendler-Scharr, Holger Tost, and Alexandra Tsimpidi
Geosci. Model Dev., 15, 2673–2710, https://doi.org/10.5194/gmd-15-2673-2022, https://doi.org/10.5194/gmd-15-2673-2022, 2022
Short summary
Short summary
A newly developed setup of the chemistry general circulation model EMAC (ECHAM5/MESSy for Atmospheric Chemistry) is evaluated here. A comprehensive organic degradation mechanism is used and coupled with a volatility base model.
The results show that the model reproduces most of the tracers and aerosols satisfactorily but shows discrepancies for oxygenated organic gases. It is also shown that this model configuration can be used for further research in atmospheric chemistry.
Guangjie Zheng, Hang Su, Siwen Wang, Andrea Pozzer, and Yafang Cheng
Atmos. Chem. Phys., 22, 47–63, https://doi.org/10.5194/acp-22-47-2022, https://doi.org/10.5194/acp-22-47-2022, 2022
Short summary
Short summary
The recently proposed multiphase buffer theory provides a framework to reconstruct long-term trends and spatial variations in aerosol pH, while non-ideality is a major limitation for its broad applications. Here we proposed a parameterization method to estimate the impact of non-ideality and validated it against long-term observations and global simulations. With this method, the multiphase buffer theory can reproduce well aerosol pH variations estimated by comprehensive thermodynamic models.
Clara M. Nussbaumer, John N. Crowley, Jan Schuladen, Jonathan Williams, Sascha Hafermann, Andreas Reiffs, Raoul Axinte, Hartwig Harder, Cheryl Ernest, Anna Novelli, Katrin Sala, Monica Martinez, Chinmay Mallik, Laura Tomsche, Christian Plass-Dülmer, Birger Bohn, Jos Lelieveld, and Horst Fischer
Atmos. Chem. Phys., 21, 18413–18432, https://doi.org/10.5194/acp-21-18413-2021, https://doi.org/10.5194/acp-21-18413-2021, 2021
Short summary
Short summary
HCHO is an important atmospheric trace gas influencing the photochemical processes in the Earth’s atmosphere, including the budget of HOx and the abundance of tropospheric O3. This research presents the photochemical calculations of HCHO and O3 based on three field campaigns across Europe. We show that HCHO production via the oxidation of only four volatile organic compound precursors, i.e., CH4, CH3CHO, C5H8 and CH3OH, can balance the observed loss at all sites well.
Dirk Dienhart, John N. Crowley, Efstratios Bourtsoukidis, Achim Edtbauer, Philipp G. Eger, Lisa Ernle, Hartwig Harder, Bettina Hottmann, Monica Martinez, Uwe Parchatka, Jean-Daniel Paris, Eva Y. Pfannerstill, Roland Rohloff, Jan Schuladen, Christof Stönner, Ivan Tadic, Sebastian Tauer, Nijing Wang, Jonathan Williams, Jos Lelieveld, and Horst Fischer
Atmos. Chem. Phys., 21, 17373–17388, https://doi.org/10.5194/acp-21-17373-2021, https://doi.org/10.5194/acp-21-17373-2021, 2021
Short summary
Short summary
We present the first ship-based in situ measurements of formaldehyde (HCHO), hydroxyl radicals (OH) and the OH reactivity around the Arabian Peninsula. Regression analysis of the HCHO production rate and the related OH chemistry revealed the regional HCHO yield αeff, which represents the different chemical regimes encountered. Highest values were found for the Arabian Gulf (also known as the Persian Gulf), which highlights this region as a hotspot of photochemical air pollution.
Clara M. Nussbaumer, Uwe Parchatka, Ivan Tadic, Birger Bohn, Daniel Marno, Monica Martinez, Roland Rohloff, Hartwig Harder, Flora Kluge, Klaus Pfeilsticker, Florian Obersteiner, Martin Zöger, Raphael Doerich, John N. Crowley, Jos Lelieveld, and Horst Fischer
Atmos. Meas. Tech., 14, 6759–6776, https://doi.org/10.5194/amt-14-6759-2021, https://doi.org/10.5194/amt-14-6759-2021, 2021
Short summary
Short summary
NO2 plays a central role in atmospheric photochemical processes and requires accurate measurements. This research presents NO2 data obtained via chemiluminescence using a photolytic converter from airborne studies around Cabo Verde and laboratory investigations. We show the limits and error-proneness of a conventional blue light converter in aircraft measurements affected by humidity and NO levels and suggest the use of an alternative quartz converter for more reliable results.
Vlassis A. Karydis, Alexandra P. Tsimpidi, Andrea Pozzer, and Jos Lelieveld
Atmos. Chem. Phys., 21, 14983–15001, https://doi.org/10.5194/acp-21-14983-2021, https://doi.org/10.5194/acp-21-14983-2021, 2021
Short summary
Short summary
Aerosol particle pH is well-buffered by alkaline compounds, notably NH3 and crustal elements. NH3 is found to supply remarkable buffering capacity on a global scale, from the polluted continents to the remote oceans. Potential future changes in agricultural NH3 must be accompanied by strong reductions of SO2 and NOx to avoid particles becoming highly acidic, with implications for human health (aerosol toxicity), ecosystems (acid deposition), clouds, and climate (aerosol hygroscopicity).
Andrea Pozzer
Geosci. Commun., 4, 453–460, https://doi.org/10.5194/gc-4-453-2021, https://doi.org/10.5194/gc-4-453-2021, 2021
Short summary
Short summary
In this paper we investigate the numbers of pages, references and references per page in open-access EGU journals. We showed that, while the number of references and number of pages have been constantly increasing in the period 2010–2020, the number of references per page did not change in the same period. Furthermore, all the journals showed a similar number of references per page, i.e. ~ 3.8 references per page.
Philipp G. Eger, Luc Vereecken, Rolf Sander, Jan Schuladen, Nicolas Sobanski, Horst Fischer, Einar Karu, Jonathan Williams, Ville Vakkari, Tuukka Petäjä, Jos Lelieveld, Andrea Pozzer, and John N. Crowley
Atmos. Chem. Phys., 21, 14333–14349, https://doi.org/10.5194/acp-21-14333-2021, https://doi.org/10.5194/acp-21-14333-2021, 2021
Short summary
Short summary
We determine the impact of pyruvic acid photolysis on the formation of acetaldehyde and peroxy radicals during summer and autumn in the Finnish boreal forest using a data-constrained box model. Our results are dependent on the chosen scenario in which the overall quantum yield and the photolysis products are varied. We highlight that pyruvic acid photolysis can be an important contributor to acetaldehyde and peroxy radical formation in remote, forested regions.
Ralf Weigel, Christoph Mahnke, Manuel Baumgartner, Martina Krämer, Peter Spichtinger, Nicole Spelten, Armin Afchine, Christian Rolf, Silvia Viciani, Francesco D'Amato, Holger Tost, and Stephan Borrmann
Atmos. Chem. Phys., 21, 13455–13481, https://doi.org/10.5194/acp-21-13455-2021, https://doi.org/10.5194/acp-21-13455-2021, 2021
Short summary
Short summary
In July and August 2017, the StratoClim mission took place in Nepal with eight flights of the M-55 Geophysica at up to 20 km in the Asian monsoon anticyclone. New particle formation (NPF) next to cloud ice was detected in situ by abundant nucleation-mode aerosols (> 6 nm) along with ice particles (> 3 µm). NPF was observed mainly below the tropopause, down to 15 % being non-volatile residues. Observed intra-cloud NPF indicates its importance for the composition in the tropical tropopause layer.
Jean-Daniel Paris, Aurélie Riandet, Efstratios Bourtsoukidis, Marc Delmotte, Antoine Berchet, Jonathan Williams, Lisa Ernle, Ivan Tadic, Hartwig Harder, and Jos Lelieveld
Atmos. Chem. Phys., 21, 12443–12462, https://doi.org/10.5194/acp-21-12443-2021, https://doi.org/10.5194/acp-21-12443-2021, 2021
Short summary
Short summary
We measured atmospheric methane and CO2 by ship in the Middle East. We probe the origin of methane with a combination of light alkane measurements and modeling. We find strong influence from nearby oil and gas production over the Arabian Gulf. Comparing our data to inventories indicates that inventories overestimate sources from the upstream gas industry but underestimate emissions from oil extraction and processing. The Red Sea was under a complex mixture of sources due to human activity.
Patrick Dewald, Raphael Dörich, Jan Schuladen, Jos Lelieveld, and John N. Crowley
Atmos. Meas. Tech., 14, 5501–5519, https://doi.org/10.5194/amt-14-5501-2021, https://doi.org/10.5194/amt-14-5501-2021, 2021
Short summary
Short summary
Organic nitrates generated from the reaction between isoprene and the nitrate radical (ISOP-NITs) were detected via their thermal dissociation in heated quartz inlets to nitrogen dioxide monitored by cavity ring-down spectroscopy. The temperature-dependent dissociation profiles of ISOP-NITs in the presence of ozone (O3) are broad in contrast to narrow profiles of common reference compounds. We demonstrate that this broadening is caused by O3-assisted reactions of ISOP-NITs on quartz surfaces.
Raphael Dörich, Philipp Eger, Jos Lelieveld, and John N. Crowley
Atmos. Meas. Tech., 14, 5319–5332, https://doi.org/10.5194/amt-14-5319-2021, https://doi.org/10.5194/amt-14-5319-2021, 2021
Short summary
Short summary
We demonstrate in laboratory experiments that the formation of IOx anions (formed in reactions of I− with O3) or acetate anions (formed e.g. by the reaction of I− with peracetic acid) results in unexpected sensitivity of an iodide chemical ionisation mass spectrometer (I-CIMS) to HNO3 at a mass-to-charge ratio of 62. This helps explain observations of apparent high daytime levels of N2O5. Airborne measurements using I-CIMS confirm these conclusions.
Vinod Kumar, Julia Remmers, Steffen Beirle, Joachim Fallmann, Astrid Kerkweg, Jos Lelieveld, Mariano Mertens, Andrea Pozzer, Benedikt Steil, Marc Barra, Holger Tost, and Thomas Wagner
Atmos. Meas. Tech., 14, 5241–5269, https://doi.org/10.5194/amt-14-5241-2021, https://doi.org/10.5194/amt-14-5241-2021, 2021
Short summary
Short summary
We present high-resolution regional atmospheric chemistry model simulations focused around Germany. We highlight the importance of spatial resolution of the model itself as well as the input emissions inventory and short-scale temporal variability of emissions for simulations. We propose a consistent approach for evaluating the simulated vertical distribution of NO2 using MAX-DOAS measurements while also considering its spatial sensitivity volume and change in sensitivity within this volume.
Simon Rosanka, Bruno Franco, Lieven Clarisse, Pierre-François Coheur, Andrea Pozzer, Andreas Wahner, and Domenico Taraborrelli
Atmos. Chem. Phys., 21, 11257–11288, https://doi.org/10.5194/acp-21-11257-2021, https://doi.org/10.5194/acp-21-11257-2021, 2021
Short summary
Short summary
The strong El Niño in 2015 led to a particular dry season in Indonesia and favoured severe peatland fires. The smouldering conditions of these fires and the high carbon content of peat resulted in high volatile organic compound (VOC) emissions. By using a comprehensive atmospheric model, we show that these emissions have a significant impact on the tropospheric composition and oxidation capacity. These emissions are transported into to the lower stratosphere, resulting in a depletion of ozone.
Cited articles
Andreae, M. O.: Emission of trace gases and aerosols from biomass burning – an updated assessment, Atmos. Chem. Phys., 19, 8523–8546, https://doi.org/10.5194/acp-19-8523-2019, 2019. a
Ashworth, K., Folberth, G., Hewitt, C. N., and Wild, O.: Impacts of near-future cultivation of biofuel feedstocks on atmospheric composition and local air quality, Atmos. Chem. Phys., 12, 919–939, https://doi.org/10.5194/acp-12-919-2012, 2012. a
Atkinson, R.: Atmospheric Chemistry of VOCs and NOx, Atmos. Environ., 34, 2063–2101, https://doi.org/10.1016/S1352-2310(99)00460-4, 2000. a, b
Atkinson, R. and Arey, J.: Gas-Phase Tropospheric Chemistry of Biogenic Volatile Organic Compounds: A Review, Atmos. Environ., 37, 197–219, https://doi.org/10.1016/S1352-2310(03)00391-1, 2003. a, b
Betts, R. A., Cox, P. M., Collins, M., Harris, P. P., Huntingford, C., and Jones, C. D.: The Role of Ecosystem-Atmosphere Interactions in Simulated Amazonian Precipitation Decrease and Forest Dieback under Global Climate Warming, Theor. Appl. Climatol., 78, 157–175, https://doi.org/10.1007/s00704-004-0050-y, 2004. a
Bonan, G. B.: Forests and Climate Change: Forcings, Feedbacks, and the Climate Benefits of Forests, Science, 320, 1444–1449, https://doi.org/10.1126/science.1155121, 2008. a
Curtius, J., Heinritzi, M., Beck, L. J., Pöhlker, M. L., Tripathi, N., Krumm, B. E., Holzbeck, P., Nussbaumer, C. M., Hernández Pardo, L., Klimach, T., Barmpounis, K., Andersen, S. T., Bardakov, R., Bohn, B., Cecchini, M. A., Chaboureau, J.-P., Dauhut, T., Dienhart, D., Dörich, R., Edtbauer, A., Giez, A., Hartmann, A., Holanda, B. A., Joppe, P., Kaiser, K., Keber, T., Klebach, H., Krüger, O. O., Kürten, A., Mallaun, C., Marno, D., Martinez, M., Monteiro, C., Nelson, C., Ort, L., Raj, S. S., Richter, S., Ringsdorf, A., Rocha, F., Simon, M., Sreekumar, S., Tsokankunku, A., Unfer, G. R., Valenti, I. D., Wang, N., Zahn, A., Zauner-Wieczorek, M., Albrecht, R. I., Andreae, M. O., Artaxo, P., Crowley, J. N., Fischer, H., Harder, H., Herdies, D. L., Machado, L. A. T., Pöhlker, C., Pöschl, U., Possner, A., Pozzer, A., Schneider, J., Williams, J., and Lelieveld, J.: Isoprene Nitrates Drive New Particle Formation in Amazon's Upper Troposphere, Nature, 636, 124–130, https://doi.org/10.1038/s41586-024-08192-4, 2024. a
Denier van der Gon, H., Gauss, M., Granier, C., Arellano, S., Benedictow, A., Darras, S., Dellaert, S., Guevara, M., Jalkanen, J.-P., Krueger, K., Kuenen, J., Liaskoni, M., Liousse, C., Markova, J., Prieto Perez, A., Quack, B., Simpson, D., Sindelarova, K., and Soulie, A.: Documentation of CAMS Emission Inventory Products, https://doi.org/10.24380/Q2SI-TI6I, 2023. a, b, c, d
Dentener, F., Kinne, S., Bond, T., Boucher, O., Cofala, J., Generoso, S., Ginoux, P., Gong, S., Hoelzemann, J. J., Ito, A., Marelli, L., Penner, J. E., Putaud, J.-P., Textor, C., Schulz, M., van der Werf, G. R., and Wilson, J.: Emissions of primary aerosol and precursor gases in the years 2000 and 1750 prescribed data-sets for AeroCom, Atmos. Chem. Phys., 6, 4321–4344, https://doi.org/10.5194/acp-6-4321-2006, 2006. a
Donahue, N. M., Robinson, A. L., Stanier, C. O., and Pandis, S. N.: Coupled Partitioning, Dilution, and Chemical Aging of Semivolatile Organics, Environ. Sci. Technol., 40, 2635–2643, https://doi.org/10.1021/es052297c, 2006. a
Elshorbany, Y., Barnes, I., Becker, K. H., Kleffmann, J., and Wiesen, P.: Sources and Cycling of Tropospheric Hydroxyl Radicals – An Overview, Zeitschrift für Physikalische Chemie, 224, 967–987, https://doi.org/10.1524/zpch.2010.6136, 2010. a
Etminan, M., Myhre, G., Highwood, E. J., and Shine, K. P.: Radiative Forcing of Carbon Dioxide, Methane, and Nitrous Oxide: A Significant Revision of the Methane Radiative Forcing, Geophys. Res. Lett., 43, 12614–12623, https://doi.org/10.1002/2016GL071930, 2016. a, b
Eyring, V., Lamarque, J.-F., Hess, P., Arfeuille, F., Bowman, K., Chipperfiel, M. P., Duncan, B., Fiore, A., Gettelman, A., Giorgetta, M. A., Granier, C., Hegglin, M., Kinnison, D., Kunze, M., Langematz, U., Luo, B., Martin, R., Matthes, K., Newman, P. A., Peter, T., Robock, A., Ryerson, T., Saiz-Lopez, A., Salawitch, R., Schultz, M., Shepherd, T. G., Shindell, D., Staehelin, J., Tegtmeier, S., Thomason, L., Tilmes, S., Vernier, J.-P., Waugh, D., and Young, P. Y.: Overview of IGAC/SPARC Chemistry-Climate Model Initiative (CCMI) Community Simulations in Support of Upcoming Ozone and Climate Assessments, SPARC Newsletter, 40, 48–66, 2013. a
Field, C. B.: The Global Carbon Cycle: Integrating Humans, Climate, and the Natural World, no. v.62 in Scientific Committee on Problems of the Environment (SCOPE) Ser, Island Press, Washington, ISBN 978-1-61091-075-0, 2004. a
Fiore, A. M., Dentener, F. J., Wild, O., Cuvelier, C., Schultz, M. G., Hess, P., Textor, C., Schulz, M., Doherty, R. M., Horowitz, L. W., MacKenzie, I. A., Sanderson, M. G., Shindell, D. T., Stevenson, D. S., Szopa, S., Van Dingenen, R., Zeng, G., Atherton, C., Bergmann, D., Bey, I., Carmichael, G., Collins, W. J., Duncan, B. N., Faluvegi, G., Folberth, G., Gauss, M., Gong, S., Hauglustaine, D., Holloway, T., Isaksen, I. S. A., Jacob, D. J., Jonson, J. E., Kaminski, J. W., Keating, T. J., Lupu, A., Marmer, E., Montanaro, V., Park, R. J., Pitari, G., Pringle, K. J., Pyle, J. A., Schroeder, S., Vivanco, M. G., Wind, P., Wojcik, G., Wu, S., and Zuber, A.: Multimodel Estimates of Intercontinental Source-Receptor Relationships for Ozone Pollution, J. Geophys. Res.-Atmos., 114, D04301, https://doi.org/10.1029/2008JD010816, 2009. a, b
Fischer, E. V., Jacob, D. J., Millet, D. B., Yantosca, R. M., and Mao, J.: The Role of the Ocean in the Global Atmospheric Budget of Acetone, Geophys. Res. Lett., 39, L01807, https://doi.org/10.1029/2011GL050086, 2012. a
Forrest, M., Tost, H., Lelieveld, J., and Hickler, T.: Including vegetation dynamics in an atmospheric chemistry-enabled general circulation model: linking LPJ-GUESS (v4.0) with the EMAC modelling system (v2.53), Geosci. Model Dev., 13, 1285–1309, https://doi.org/10.5194/gmd-13-1285-2020, 2020. a
Forster, P., Ramaswamy, V., Artaxo, P., Berntsen, T., Betts, R., Fahey, D. W., Haywood, J., Lean, J., Lowe, D. C., Myhre, G., Nganga, J., Prinn, R., Raga, G., Schulz, M., and Van Dorland, R.: Changes in Atmospheric Constituents and in Radiative Forcing, in: Climate Change 2007: The Physical Science Basis. Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, edited by: Solomon, S., Qin, D., Manning, M., Chen, Z., Marquis, M., Averyt, K. B., Tignor, M., and Miller, H. L., Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA, https://www.ipcc.ch/report/ar4/wg1/ (last access: 1 September 2025), 2007. a
Ganzeveld, L. and Lelieveld, J.: Impact of Amazonian Deforestation on Atmospheric Chemistry, Geophys. Res. Lett., 31, L06105, https://doi.org/10.1029/2003GL019205, 2004. a, b
Ganzeveld, L., Bouwman, L., Stehfest, E., van Vuuren, D. P., Eickhout, B., and Lelieveld, J.: Impact of Future Land Use and Land Cover Changes on Atmospheric Chemistry-Climate Interactions, J. Geophys. Res.-Atmos., 115, D23301, https://doi.org/10.1029/2010JD014041, 2010. a, b
Gaudel, A., Cooper, O. R., Ancellet, G., Barret, B., Boynard, A., Burrows, J. P., Clerbaux, C., Coheur, P.-F., Cuesta, J., Cuevas, E., Doniki, S., Dufour, G., Ebojie, F., Foret, G., Garcia, O., Granados-Muñoz, M. J., Hannigan, J. W., Hase, F., Hassler, B., Huang, G., Hurtmans, D., Jaffe, D., Jones, N., Kalabokas, P., Kerridge, B., Kulawik, S., Latter, B., Leblanc, T., Le Flochmoën, E., Lin, W., Liu, J., Liu, X., Mahieu, E., McClure-Begley, A., Neu, J. L., Osman, M., Palm, M., Petetin, H., Petropavlovskikh, I., Querel, R., Rahpoe, N., Rozanov, A., Schultz, M. G., Schwab, J., Siddans, R., Smale, D., Steinbacher, M., Tanimoto, H., Tarasick, D. W., Thouret, V., Thompson, A. M., Trickl, T., Weatherhead, E., Wespes, C., Worden, H. M., Vigouroux, C., Xu, X., Zeng, G., and Ziemke, J.: Tropospheric Ozone Assessment Report: Present-day Distribution and Trends of Tropospheric Ozone Relevant to Climate and Global Atmospheric Chemistry Model Evaluation, Elementa: Science of the Anthropocene, 6, 39, https://doi.org/10.1525/elementa.291, 2018. a
Gibbard, S., Caldeira, K., Bala, G., Phillips, T. J., and Wickett, M.: Climate Effects of Global Land Cover Change, Geophys. Res. Lett., 32, 2005GL024550, https://doi.org/10.1029/2005GL024550, 2005. a
Granier, C., Pétron, G., Müller, J.-F., and Brasseur, G.: The Impact of Natural and Anthropogenic Hydrocarbons on the Tropospheric Budget of Carbon Monoxide, Atmos. Environ., 34, 5255–5270, https://doi.org/10.1016/S1352-2310(00)00299-5, 2000. a
Granier, C., Darras, S., Denier van Der Gon, H., Jana, D., Elguindi, N., Bo, G., Michael, G., Marc, G., Jalkanen, J.-P., Kuenen, J., Liousse, C., Quack, B., Simpson, D., and Sindelarova, K.: The Copernicus Atmosphere Monitoring Service Global and Regional Emissions (April 2019 Version), Research Report, Copernicus Atmosphere Monitoring Service, https://doi.org/10.24380/d0bn-kx16, 2019. a
Gromov, S., Jöckel, P., Sander, R., and Brenninkmeijer, C. A. M.: A kinetic chemistry tagging technique and its application to modelling the stable isotopic composition of atmospheric trace gases, Geosci. Model Dev., 3, 337–364, https://doi.org/10.5194/gmd-3-337-2010, 2010. a, b
Guelle, W., Schulz, M., Balkanski, Y., and Dentener, F.: Influence of the Source Formulation on Modeling the Atmospheric Global Distribution of Sea Salt Aerosol, J. Geophys. Res.-Atmos., 106, 27509–27524, https://doi.org/10.1029/2001JD900249, 2001. a
Guenther, A., Hewitt, C. N., Erickson, D., Fall, R., Geron, C., Graedel, T., Harley, P., Klinger, L., Lerdau, M., Mckay, W. A., Pierce, T., Scholes, B., Steinbrecher, R., Tallamraju, R., Taylor, J., and Zimmerman, P.: A Global Model of Natural Volatile Organic Compound Emissions, J. Geophys. Res.-Atmos., 100, 8873–8892, https://doi.org/10.1029/94JD02950, 1995. a, b
Guenther, A., Karl, T., Harley, P., Wiedinmyer, C., Palmer, P. I., and Geron, C.: Estimates of global terrestrial isoprene emissions using MEGAN (Model of Emissions of Gases and Aerosols from Nature), Atmos. Chem. Phys., 6, 3181–3210, https://doi.org/10.5194/acp-6-3181-2006, 2006. a
Guenther, A. B., Zimmerman, P. R., Harley, P. C., Monson, R. K., and Fall, R.: Isoprene and Monoterpene Emission Rate Variability: Model Evaluations and Sensitivity Analyses, J. Geophys. Res.-Atmos., 98, 12609–12617, https://doi.org/10.1029/93JD00527, 1993. a
Hagemann, S.: An Improved Land Surface Parameter Dataset for Global and Regional Climate Models, Report, Max-Planck-Institut für Meteorologie, https://doi.org/10.17617/2.2344576, 2002. a
Heald, C. L. and Spracklen, D. V.: Land Use Change Impacts on Air Quality and Climate, Chem. Rev., 115, 4476–4496, https://doi.org/10.1021/cr500446g, 2015. a
Heald, C. L., Henze, D. K., Horowitz, L. W., Feddema, J., Lamarque, J.-F., Guenther, A., Hess, P. G., Vitt, F., Seinfeld, J. H., Goldstein, A. H., and Fung, I.: Predicted Change in Global Secondary Organic Aerosol Concentrations in Response to Future Climate, Emissions, and Land Use Change, J. Geophys. Res.-Atmos., 113, 2007JD009092, https://doi.org/10.1029/2007JD009092, 2008. a, b
Hurtt, G. C., Chini, L. P., Frolking, S., Betts, R. A., Feddema, J., Fischer, G., Fisk, J. P., Hibbard, K., Houghton, R. A., Janetos, A., Jones, C. D., Kindermann, G., Kinoshita, T., Klein Goldewijk, K., Riahi, K., Shevliakova, E., Smith, S., Stehfest, E., Thomson, A., Thornton, P., Van Vuuren, D. P., and Wang, Y. P.: Harmonization of Land-Use Scenarios for the Period 1500–2100: 600 Years of Global Gridded Annual Land-Use Transitions, Wood Harvest, and Resulting Secondary Lands, Climatic Change, 109, 117–161, https://doi.org/10.1007/s10584-011-0153-2, 2011. a, b
IUPAC: Evaluated kinetic data, AERIS [data set], https://iupac.aeris-data.fr/, last access: 13 April 2025. a
Jöckel, P., Sander, R., Kerkweg, A., Tost, H., and Lelieveld, J.: Technical Note: The Modular Earth Submodel System (MESSy) – a new approach towards Earth System Modeling, Atmos. Chem. Phys., 5, 433–444, https://doi.org/10.5194/acp-5-433-2005, 2005. a
Jöckel, P., Tost, H., Pozzer, A., Brühl, C., Buchholz, J., Ganzeveld, L., Hoor, P., Kerkweg, A., Lawrence, M. G., Sander, R., Steil, B., Stiller, G., Tanarhte, M., Taraborrelli, D., van Aardenne, J., and Lelieveld, J.: The atmospheric chemistry general circulation model ECHAM5/MESSy1: consistent simulation of ozone from the surface to the mesosphere, Atmos. Chem. Phys., 6, 5067–5104, https://doi.org/10.5194/acp-6-5067-2006, 2006. a
Keller, M., Jacob, D. J., Wofsy, S. C., and Harriss, R. C.: Effects of Tropical Deforestation on Global and Regional Atmospheric Chemistry, Climatic Change, 19, 139–158, https://doi.org/10.1007/BF00142221, 1991. a
Kerkweg, A., Sander, R., Tost, H., and Jöckel, P.: Technical note: Implementation of prescribed (OFFLEM), calculated (ONLEM), and pseudo-emissions (TNUDGE) of chemical species in the Modular Earth Submodel System (MESSy), Atmos. Chem. Phys., 6, 3603–3609, https://doi.org/10.5194/acp-6-3603-2006, 2006. a, b
Klingmüller, K., Metzger, S., Abdelkader, M., Karydis, V. A., Stenchikov, G. L., Pozzer, A., and Lelieveld, J.: Revised mineral dust emissions in the atmospheric chemistry–climate model EMAC (MESSy 2.52 DU_Astitha1 KKDU2017 patch), Geosci. Model Dev., 11, 989–1008, https://doi.org/10.5194/gmd-11-989-2018, 2018. a
Lana, A., Bell, T. G., Simó, R., Vallina, S. M., Ballabrera-Poy, J., Kettle, A. J., Dachs, J., Bopp, L., Saltzman, E. S., Stefels, J., Johnson, J. E., and Liss, P. S.: An Updated Climatology of Surface Dimethlysulfide Concentrations and Emission Fluxes in the Global Ocean, Global Biogeochem. Cy., 25, GB1004, https://doi.org/10.1029/2010GB003850, 2011. a
Lelieveld, J., Butler, T. M., Crowley, J. N., Dillon, T. J., Fischer, H., Ganzeveld, L., Harder, H., Lawrence, M. G., Martinez, M., Taraborrelli, D., and Williams, J.: Atmospheric Oxidation Capacity Sustained by a Tropical Forest, Nature, 452, 737–740, https://doi.org/10.1038/nature06870, 2008. a, b
Levy, H.: Normal Atmosphere: Large Radical and Formaldehyde Concentrations Predicted, Science, 173, 141–143, https://doi.org/10.1126/science.173.3992.141, 1971. a
Li, M., Song, Y., Liu, M., Yao, H., Huang, X., Wang, X., and Zhang, Y.: Impacts of Decadal Variations in Natural Emissions Due to Land-Cover Changes on Ozone Production in Southern China, Tellus B, 67, 27676, https://doi.org/10.3402/tellusb.v67.27676, 2015. a
Naik, V., Voulgarakis, A., Fiore, A. M., Horowitz, L. W., Lamarque, J.-F., Lin, M., Prather, M. J., Young, P. J., Bergmann, D., Cameron-Smith, P. J., Cionni, I., Collins, W. J., Dalsøren, S. B., Doherty, R., Eyring, V., Faluvegi, G., Folberth, G. A., Josse, B., Lee, Y. H., MacKenzie, I. A., Nagashima, T., van Noije, T. P. C., Plummer, D. A., Righi, M., Rumbold, S. T., Skeie, R., Shindell, D. T., Stevenson, D. S., Strode, S., Sudo, K., Szopa, S., and Zeng, G.: Preindustrial to present-day changes in tropospheric hydroxyl radical and methane lifetime from the Atmospheric Chemistry and Climate Model Intercomparison Project (ACCMIP), Atmos. Chem. Phys., 13, 5277–5298, https://doi.org/10.5194/acp-13-5277-2013, 2013. a
Nordeng, E. T.: Extended Versions of the Convective Parametrization Scheme at ECMWF and Their Impact on the Mean and Transient Activity of the Model in the Tropics, Research Department Technical Memorandum, 206, 1–41, https://doi.org/10.1002/qj.49711448106, 1994. a
Nussbaumer, C. M., Crowley, J. N., Schuladen, J., Williams, J., Hafermann, S., Reiffs, A., Axinte, R., Harder, H., Ernest, C., Novelli, A., Sala, K., Martinez, M., Mallik, C., Tomsche, L., Plass-Dülmer, C., Bohn, B., Lelieveld, J., and Fischer, H.: Measurement report: Photochemical production and loss rates of formaldehyde and ozone across Europe, Atmos. Chem. Phys., 21, 18413–18432, https://doi.org/10.5194/acp-21-18413-2021, 2021. a, b
Nussbaumer, C. M., Fischer, H., Lelieveld, J., and Pozzer, A.: What controls ozone sensitivity in the upper tropical troposphere?, Atmos. Chem. Phys., 23, 12651–12669, https://doi.org/10.5194/acp-23-12651-2023, 2023. a
Nussbaumer, C. M., Kohl, M., Pozzer, A., Tadic, I., Rohloff, R., Marno, D., Harder, H., Ziereis, H., Zahn, A., Obersteiner, F., Hofzumahaus, A., Fuchs, H., Künstler, C., Brune, W. H., Ryerson, T. B., Peischl, J., Thompson, C. R., Bourgeois, I., Lelieveld, J., and Fischer, H.: Ozone Formation Sensitivity to Precursors and Lightning in the Tropical Troposphere Based on Airborne Observations, J. Geophys. Res.-Atmos., 129, e2024JD041168, https://doi.org/10.1029/2024JD041168, 2024. a, b, c
Pan, Y., Birdsey, R. A., Fang, J., Houghton, R., Kauppi, P. E., Kurz, W. A., Phillips, O. L., Shvidenko, A., Lewis, S. L., Canadell, J. G., Ciais, P., Jackson, R. B., Pacala, S. W., McGuire, A. D., Piao, S., Rautiainen, A., Sitch, S., and Hayes, D.: A Large and Persistent Carbon Sink in the World's Forests, Science, 333, 988–993, https://doi.org/10.1126/science.1201609, 2011. a
Pöschl, U., von Kuhlmann, R., Poisson, N., and Crutzen, P. J.: Development and Intercomparison of Condensed Isoprene Oxidation Mechanisms for Global Atmospheric Modeling, J. Atmos. Chem., 37, 29–52, https://doi.org/10.1023/A:1006391009798, 2000. a
Pozzer, A., Jöckel, P., Sander, R., Williams, J., Ganzeveld, L., and Lelieveld, J.: Technical Note: The MESSy-submodel AIRSEA calculating the air-sea exchange of chemical species, Atmos. Chem. Phys., 6, 5435–5444, https://doi.org/10.5194/acp-6-5435-2006, 2006. a
Pringle, K. J., Tost, H., Message, S., Steil, B., Giannadaki, D., Nenes, A., Fountoukis, C., Stier, P., Vignati, E., and Lelieveld, J.: Description and evaluation of GMXe: a new aerosol submodel for global simulations (v1), Geosci. Model Dev., 3, 391–412, https://doi.org/10.5194/gmd-3-391-2010, 2010. a
Randerson, J. T., Van Der Werf, G. R., Giglio, L., Collatz, G. J., and Kasibhatla, P. S.: Global Fire Emissions Database, Version 4.1 (GFEDv4), ORNL DAAC [data set], https://doi.org/10.3334/ORNLDAAC/1293, 2015. a
Roeckner, E., Brokopf, R., Esch, M., Giorgetta, M., Hagemann, S., Kornblueh, L., Manzini, E., Schlese, U., and Schulzweida, U.: Sensitivity of Simulated Climate to Horizontal and Vertical Resolution in the ECHAM5 Atmosphere Model, J. Climate, 19, 3771–3791, https://doi.org/10.1175/JCLI3824.1, 2006. a
Sander, R., Baumgaertner, A., Cabrera-Perez, D., Frank, F., Gromov, S., Grooß, J.-U., Harder, H., Huijnen, V., Jöckel, P., Karydis, V. A., Niemeyer, K. E., Pozzer, A., Riede, H., Schultz, M. G., Taraborrelli, D., and Tauer, S.: The community atmospheric chemistry box model CAABA/MECCA-4.0, Geosci. Model Dev., 12, 1365–1385, https://doi.org/10.5194/gmd-12-1365-2019, 2019. a
Scott, C. E., Rap, A., Spracklen, D. V., Forster, P. M., Carslaw, K. S., Mann, G. W., Pringle, K. J., Kivekäs, N., Kulmala, M., Lihavainen, H., and Tunved, P.: The direct and indirect radiative effects of biogenic secondary organic aerosol, Atmos. Chem. Phys., 14, 447–470, https://doi.org/10.5194/acp-14-447-2014, 2014. a
Scott, C. E., Monks, S. A., Spracklen, D. V., Arnold, S. R., Forster, P. M., Rap, A., Äijälä, M., Artaxo, P., Carslaw, K. S., Chipperfield, M. P., Ehn, M., Gilardoni, S., Heikkinen, L., Kulmala, M., Petäjä, T., Reddington, C. L. S., Rizzo, L. V., Swietlicki, E., Vignati, E., and Wilson, C.: Impact on Short-Lived Climate Forcers Increases Projected Warming Due to Deforestation, Nat. Commun., 9, 157, https://doi.org/10.1038/s41467-017-02412-4, 2018. a, b, c, d, e, f
Smith, B., Prentice, I. C., and Sykes, M. T.: Representation of Vegetation Dynamics in the Modelling of Terrestrial Ecosystems: Comparing Two Contrasting Approaches within European Climate Space, Global Ecol. Biogeogr., 10, 621–637, 2001. a
Smith, B., Wårlind, D., Arneth, A., Hickler, T., Leadley, P., Siltberg, J., and Zaehle, S.: Implications of incorporating N cycling and N limitations on primary production in an individual-based dynamic vegetation model, Biogeosciences, 11, 2027–2054, https://doi.org/10.5194/bg-11-2027-2014, 2014. a
Smith, C. J., Kramer, R. J., Myhre, G., Forster, P. M., Soden, B. J., Andrews, T., Boucher, O., Faluvegi, G., Fläschner, D., Hodnebrog, Ø., Kasoar, M., Kharin, V., Kirkevåg, A., Lamarque, J.-F., Mülmenstädt, J., Olivié, D., Richardson, T., Samset, B. H., Shindell, D., Stier, P., Takemura, T., Voulgarakis, A., and Watson-Parris, D.: Understanding Rapid Adjustments to Diverse Forcing Agents, Geophys. Res. Lett., 45, 12023–12031, https://doi.org/10.1029/2018GL079826, 2018. a
Spracklen, D. V., Jimenez, J. L., Carslaw, K. S., Worsnop, D. R., Evans, M. J., Mann, G. W., Zhang, Q., Canagaratna, M. R., Allan, J., Coe, H., McFiggans, G., Rap, A., and Forster, P.: Aerosol mass spectrometer constraint on the global secondary organic aerosol budget, Atmos. Chem. Phys., 11, 12109–12136, https://doi.org/10.5194/acp-11-12109-2011, 2011. a
Stevenson, D. S., Young, P. J., Naik, V., Lamarque, J.-F., Shindell, D. T., Voulgarakis, A., Skeie, R. B., Dalsoren, S. B., Myhre, G., Berntsen, T. K., Folberth, G. A., Rumbold, S. T., Collins, W. J., MacKenzie, I. A., Doherty, R. M., Zeng, G., van Noije, T. P. C., Strunk, A., Bergmann, D., Cameron-Smith, P., Plummer, D. A., Strode, S. A., Horowitz, L., Lee, Y. H., Szopa, S., Sudo, K., Nagashima, T., Josse, B., Cionni, I., Righi, M., Eyring, V., Conley, A., Bowman, K. W., Wild, O., and Archibald, A.: Tropospheric ozone changes, radiative forcing and attribution to emissions in the Atmospheric Chemistry and Climate Model Intercomparison Project (ACCMIP), Atmos. Chem. Phys., 13, 3063–3085, https://doi.org/10.5194/acp-13-3063-2013, 2013. a
Stevenson, D. S., Zhao, A., Naik, V., O'Connor, F. M., Tilmes, S., Zeng, G., Murray, L. T., Collins, W. J., Griffiths, P. T., Shim, S., Horowitz, L. W., Sentman, L. T., and Emmons, L.: Trends in global tropospheric hydroxyl radical and methane lifetime since 1850 from AerChemMIP, Atmos. Chem. Phys., 20, 12905–12920, https://doi.org/10.5194/acp-20-12905-2020, 2020. a
Swann, A. L. S., Fung, I. Y., and Chiang, J. C. H.: Mid-Latitude Afforestation Shifts General Circulation and Tropical Precipitation, P. Natl. Acad. Sci. USA, 109, 712–716, https://doi.org/10.1073/pnas.1116706108, 2012. a
The MESSy Consortium: The Modular Earth Submodel System (2.55.2_no-branch_7639642e_airtrac-SO4), Zenodo [code], https://doi.org/10.5281/zenodo.15965933, 2025. a
Thornhill, G., Collins, W., Olivié, D., Skeie, R. B., Archibald, A., Bauer, S., Checa-Garcia, R., Fiedler, S., Folberth, G., Gjermundsen, A., Horowitz, L., Lamarque, J.-F., Michou, M., Mulcahy, J., Nabat, P., Naik, V., O'Connor, F. M., Paulot, F., Schulz, M., Scott, C. E., Séférian, R., Smith, C., Takemura, T., Tilmes, S., Tsigaridis, K., and Weber, J.: Climate-driven chemistry and aerosol feedbacks in CMIP6 Earth system models, Atmos. Chem. Phys., 21, 1105–1126, https://doi.org/10.5194/acp-21-1105-2021, 2021. a, b, c
Tiedtke, M.: A Comprehensive Mass Flux Scheme for Cumulus Parameterization in Large-Scale Models, Mon. Weather Rev., 117, 1779–1800, https://doi.org/10.1175/1520-0493(1989)117<1779:ACMFSF>2.0.CO;2, 1989. a
Tost, H., Jöckel, P., Kerkweg, A., Sander, R., and Lelieveld, J.: Technical note: A new comprehensive SCAVenging submodel for global atmospheric chemistry modelling, Atmos. Chem. Phys., 6, 565–574, https://doi.org/10.5194/acp-6-565-2006, 2006a. a
Tost, H., Jöckel, P., and Lelieveld, J.: Influence of different convection parameterisations in a GCM, Atmos. Chem. Phys., 6, 5475–5493, https://doi.org/10.5194/acp-6-5475-2006, 2006b. a
Tripathi, N., Krumm, B. E., Edtbauer, A., Ringsdorf, A., Wang, N., Kohl, M., Vella, R., Machado, L. A. T., Pozzer, A., Lelieveld, J., and Williams, J.: Impacts of convection, chemistry, and forest clearing on biogenic volatile organic compounds over the Amazon, Nat. Commun., 16, 4692, https://doi.org/10.1038/s41467-025-59953-2, 2025. a
Tsimpidi, A. P., Karydis, V. A., Pozzer, A., Pandis, S. N., and Lelieveld, J.: ORACLE (v1.0): module to simulate the organic aerosol composition and evolution in the atmosphere, Geosci. Model Dev., 7, 3153–3172, https://doi.org/10.5194/gmd-7-3153-2014, 2014. a, b
Tsimpidi, A. P., Karydis, V. A., Pozzer, A., Pandis, S. N., and Lelieveld, J.: ORACLE 2-D (v2.0): an efficient module to compute the volatility and oxygen content of organic aerosol with a global chemistry–climate model, Geosci. Model Dev., 11, 3369–3389, https://doi.org/10.5194/gmd-11-3369-2018, 2018. a
Unger, N.: Human Land-Use-Driven Reduction of Forest Volatiles Cools Global Climate, Nat. Clim. Change, 4, 907–910, https://doi.org/10.1038/nclimate2347, 2014. a, b
Vella, R.: Model simulation data used in “Changes in global atmospheric oxidant chemistry from land cover conversion” (Vella et al., 2025), Zenodo [code and data set], https://doi.org/10.5281/zenodo.15657162, 2025. a
Vella, R., Forrest, M., Lelieveld, J., and Tost, H.: Isoprene and monoterpene simulations using the chemistry–climate model EMAC (v2.55) with interactive vegetation from LPJ-GUESS (v4.0), Geosci. Model Dev., 16, 885–906, https://doi.org/10.5194/gmd-16-885-2023, 2023a. a, b
Vella, R., Pozzer, A., Forrest, M., Lelieveld, J., Hickler, T., and Tost, H.: Changes in biogenic volatile organic compound emissions in response to the El Niño–Southern Oscillation, Biogeosciences, 20, 4391–4412, https://doi.org/10.5194/bg-20-4391-2023, 2023b. a
Vicente-Serrano, S. M., Van Der Schrier, G., Beguería, S., Azorin-Molina, C., and Lopez-Moreno, J.-I.: Contribution of Precipitation and Reference Evapotranspiration to Drought Indices under Different Climates, J. Hydrol., 526, 42–54, https://doi.org/10.1016/j.jhydrol.2014.11.025, 2015. a
Voulgarakis, A., Naik, V., Lamarque, J.-F., Shindell, D. T., Young, P. J., Prather, M. J., Wild, O., Field, R. D., Bergmann, D., Cameron-Smith, P., Cionni, I., Collins, W. J., Dalsøren, S. B., Doherty, R. M., Eyring, V., Faluvegi, G., Folberth, G. A., Horowitz, L. W., Josse, B., MacKenzie, I. A., Nagashima, T., Plummer, D. A., Righi, M., Rumbold, S. T., Stevenson, D. S., Strode, S. A., Sudo, K., Szopa, S., and Zeng, G.: Analysis of present day and future OH and methane lifetime in the ACCMIP simulations, Atmos. Chem. Phys., 13, 2563–2587, https://doi.org/10.5194/acp-13-2563-2013, 2013. a
Wang, L., Tai, A. P. K., Tam, C.-Y., Sadiq, M., Wang, P., and Cheung, K. K. W.: Impacts of future land use and land cover change on mid-21st-century surface ozone air quality: distinguishing between the biogeophysical and biogeochemical effects, Atmos. Chem. Phys., 20, 11349–11369, https://doi.org/10.5194/acp-20-11349-2020, 2020. a
Weber, J., King, J. A., Abraham, N. L., Grosvenor, D. P., Smith, C. J., Shin, Y. M., Lawrence, P., Roe, S., Beerling, D. J., and Martin, M. V.: Chemistry-Albedo Feedbacks Offset up to a Third of Forestation's CO2 Removal Benefits, Science, 383, 860–864, https://doi.org/10.1126/science.adg6196, 2024. a, b, c, d
Wu, S., Mickley, L. J., Kaplan, J. O., and Jacob, D. J.: Impacts of changes in land use and land cover on atmospheric chemistry and air quality over the 21st century, Atmos. Chem. Phys., 12, 1597–1609, https://doi.org/10.5194/acp-12-1597-2012, 2012. a, b, c
Short summary
This work examines the impact of replacing forests with farmland and grazing areas on atmospheric composition. Using a global climate–chemistry model, we found that deforestation reduces biogenic volatile organic compounds (BVOCs), increases farming emissions, and shifts ozone chemistry. These changes result in a slight cooling effect on the climate. Restoring natural vegetation could reverse some of these effects.
This work examines the impact of replacing forests with farmland and grazing areas on...
Altmetrics
Final-revised paper
Preprint