Articles | Volume 14, issue 18
https://doi.org/10.5194/acp-14-9855-2014
© Author(s) 2014. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
https://doi.org/10.5194/acp-14-9855-2014
© Author(s) 2014. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Research article
| Highlight paper
| 
17 Sep 2014
Research article | Highlight paper |
| 17 Sep 2014
Tropospheric ozone increases over the southern Africa region: bellwether for rapid growth in Southern Hemisphere pollution?
A. M. Thompson
NASA/Goddard Space Flight Center, Code 614, Greenbelt, MD 20771, USA
Pennsylvania State University Dept. of Meteorology, University Park, PA 16802, USA
N. V. Balashov
Pennsylvania State University Dept. of Meteorology, University Park, PA 16802, USA
J. C. Witte
NASA/Goddard Space Flight Center, Code 614, Greenbelt, MD 20771, USA
SSAI, Lanham, MD 20706, USA
J. G. R. Coetzee
South African Weather Service, Pretoria, South Africa
V. Thouret
Laboratoire D'Aerologie, Obs. Du Midi-Pyrénées, Toulouse, France
Atmosphere and Cyclone Lab, Université de La Réunion, La Réunion, France
Related authors
Roeland Van Malderen, Anne M. Thompson, Debra E. Kollonige, Ryan M. Stauffer, Herman G. J. Smit, Eliane Maillard Barras, Corinne Vigouroux, Irina Petropavlovskikh, Thierry Leblanc, Valérie Thouret, Pawel Wolff, Peter Effertz, David W. Tarasick, Deniz Poyraz, Gérard Ancellet, Marie-Renée De Backer, Stéphanie Evan, Victoria Flood, Matthias M. Frey, James W. Hannigan, José L. Hernandez, Marco Iarlori, Bryan J. Johnson, Nicholas Jones, Rigel Kivi, Emmanuel Mahieu, Glen McConville, Katrin Müller, Tomoo Nagahama, Justus Notholt, Ankie Piters, Natalia Prats, Richard Querel, Dan Smale, Wolfgang Steinbrecht, Kimberly Strong, and Ralf Sussmann
Atmos. Chem. Phys., 25, 7187–7225, https://doi.org/10.5194/acp-25-7187-2025, https://doi.org/10.5194/acp-25-7187-2025, 2025
Short summary
Short summary
Tropospheric ozone is an important greenhouse gas and is an air pollutant. The time variability of tropospheric ozone is mainly driven by anthropogenic emissions. In this paper, we study the distribution and time variability of ozone from harmonized ground-based observations from five different measurement techniques. Our findings provide clear standard references for atmospheric models and evolving tropospheric ozone satellite data for the 2000–2022 period.
Min Huang, Gregory R. Carmichael, Kevin W. Bowman, Isabelle De Smedt, Andreas Colliander, Michael H. Cosh, Sujay V. Kumar, Alex B. Guenther, Scott J. Janz, Ryan M. Stauffer, Anne M. Thompson, Niko M. Fedkin, Robert J. Swap, John D. Bolten, and Alicia T. Joseph
Atmos. Chem. Phys., 25, 1449–1476, https://doi.org/10.5194/acp-25-1449-2025, https://doi.org/10.5194/acp-25-1449-2025, 2025
Short summary
Short summary
We use model simulations along with multiplatform, multidisciplinary observations and a range of analysis methods to estimate and understand the distributions, temporal changes, and impacts of reactive nitrogen and ozone over the most populous US region that has undergone significant environmental changes. Deposition, biogenic emissions, and extra-regional sources have been playing increasingly important roles in controlling pollutant budgets in this area as local anthropogenic emissions drop.
Anne M. Thompson, Ryan M. Stauffer, Debra E. Kollonige, Jerald R. Ziemke, Maria Cazorla, Pawel Wolff, and Bastien Sauvage
EGUsphere, https://doi.org/10.5194/egusphere-2024-3761, https://doi.org/10.5194/egusphere-2024-3761, 2025
Short summary
Short summary
This paper uses tropical ozone profiles from balloon borne instruments and aircraft to show that ozone in the free troposphere is not growing fast except over equatorial SE Asia.
Roeland Van Malderen, Zhou Zang, Kai-Lan Chang, Robin Björklund, Owen R. Cooper, Jane Liu, Eliane Maillard Barras, Corinne Vigouroux, Irina Petropavlovskikh, Thierry Leblanc, Valérie Thouret, Pawel Wolff, Peter Effertz, Audrey Gaudel, David W. Tarasick, Herman G. J. Smit, Anne M. Thompson, Ryan M. Stauffer, Debra E. Kollonige, Deniz Poyraz, Gérard Ancellet, Marie-Renée De Backer, Matthias M. Frey, James W. Hannigan, José L. Hernandez, Bryan J. Johnson, Nicholas Jones, Rigel Kivi, Emmanuel Mahieu, Isamu Morino, Glen McConville, Katrin Müller, Isao Murata, Justus Notholt, Ankie Piters, Maxime Prignon, Richard Querel, Vincenzo Rizi, Dan Smale, Wolfgang Steinbrecht, Kimberly Strong, and Ralf Sussmann
EGUsphere, https://doi.org/10.5194/egusphere-2024-3745, https://doi.org/10.5194/egusphere-2024-3745, 2025
Short summary
Short summary
Tropospheric ozone is an important greenhouse gas and an air pollutant, whose distribution and time variability is mainly governed by anthropogenic emissions and dynamics. In this paper, we assess regional trends of tropospheric ozone column amounts, based on two different approaches of merging or synthesizing ground-based observations and their trends within specific regions. Our findings clearly demonstrate regional trend differences, but also consistently higher pre- than post-COVID trends.
Zhou Zang, Jane Liu, David Tarasick, Omid Moeini, Jianchun Bian, Jinqiang Zhang, Anne M. Thompson, Roeland Van Malderen, Herman G. J. Smit, Ryan M. Stauffer, Bryan J. Johnson, and Debra E. Kollonige
Atmos. Chem. Phys., 24, 13889–13912, https://doi.org/10.5194/acp-24-13889-2024, https://doi.org/10.5194/acp-24-13889-2024, 2024
Short summary
Short summary
The Trajectory-mapped Ozonesonde dataset for the Stratosphere and Troposphere (TOST) provides a global-scale, long-term ozone climatology that is horizontally and vertically resolved. In this study, we improved, updated and validated TOST from 1970 to 2021. Based on this TOST dataset, we characterized global ozone variations spatially in both the troposphere and stratosphere and temporally by season and decade. We also showed a stagnant lower stratospheric ozone variation since the late 1990s.
Jiansheng Zou, Kaley A. Walker, Patrick E. Sheese, Chris D. Boone, Ryan M. Stauffer, Anne M. Thompson, and David W. Tarasick
Atmos. Meas. Tech., 17, 6983–7005, https://doi.org/10.5194/amt-17-6983-2024, https://doi.org/10.5194/amt-17-6983-2024, 2024
Short summary
Short summary
Ozone measurements from the ACE-FTS satellite instrument have been compared to worldwide balloon-borne ozonesonde profiles using pairs of closely spaced profiles and monthly averaged profiles. ACE-FTS typically measures more ozone in the stratosphere by up to 10 %. The long-term stability of the ACE-FTS ozone data is good, exhibiting small (but non-significant) drifts of less than 3 % per decade in the stratosphere. Lower in the profiles, the calculated drifts are larger (up to 10 % per decade).
Swathi Maratt Satheesan, Kai-Uwe Eichmann, John P. Burrows, Mark Weber, Ryan Stauffer, Anne M. Thompson, and Debra Kollonige
Atmos. Meas. Tech., 17, 6459–6484, https://doi.org/10.5194/amt-17-6459-2024, https://doi.org/10.5194/amt-17-6459-2024, 2024
Short summary
Short summary
CHORA, an advanced cloud convective differential technique, enhances the accuracy of tropospheric-ozone retrievals. Unlike the traditional Pacific cloud reference sector scheme, CHORA introduces a local-cloud reference sector and an alternative approach (CLCT) for precision. Analysing monthly averaged TROPOMI data from 2018 to 2022 and validating with SHADOZ ozonesonde data, CLCT outperforms other methods and so is the preferred choice, especially in future geostationary satellite missions.
Audrey Gaudel, Ilann Bourgeois, Meng Li, Kai-Lan Chang, Jerald Ziemke, Bastien Sauvage, Ryan M. Stauffer, Anne M. Thompson, Debra E. Kollonige, Nadia Smith, Daan Hubert, Arno Keppens, Juan Cuesta, Klaus-Peter Heue, Pepijn Veefkind, Kenneth Aikin, Jeff Peischl, Chelsea R. Thompson, Thomas B. Ryerson, Gregory J. Frost, Brian C. McDonald, and Owen R. Cooper
Atmos. Chem. Phys., 24, 9975–10000, https://doi.org/10.5194/acp-24-9975-2024, https://doi.org/10.5194/acp-24-9975-2024, 2024
Short summary
Short summary
The study examines tropical tropospheric ozone changes. In situ data from 1994–2019 display increased ozone, notably over India, Southeast Asia, and Malaysia and Indonesia. Sparse in situ data limit trend detection for the 15-year period. In situ and satellite data, with limited sampling, struggle to consistently detect trends. Continuous observations are vital over the tropical Pacific Ocean, Indian Ocean, western Africa, and South Asia for accurate ozone trend estimation in these regions.
Arno Keppens, Serena Di Pede, Daan Hubert, Jean-Christopher Lambert, Pepijn Veefkind, Maarten Sneep, Johan De Haan, Mark ter Linden, Thierry Leblanc, Steven Compernolle, Tijl Verhoelst, José Granville, Oindrila Nath, Ann Mari Fjæraa, Ian Boyd, Sander Niemeijer, Roeland Van Malderen, Herman G. J. Smit, Valentin Duflot, Sophie Godin-Beekmann, Bryan J. Johnson, Wolfgang Steinbrecht, David W. Tarasick, Debra E. Kollonige, Ryan M. Stauffer, Anne M. Thompson, Angelika Dehn, and Claus Zehner
Atmos. Meas. Tech., 17, 3969–3993, https://doi.org/10.5194/amt-17-3969-2024, https://doi.org/10.5194/amt-17-3969-2024, 2024
Short summary
Short summary
The Sentinel-5P satellite operated by the European Space Agency has carried the TROPOspheric Monitoring Instrument (TROPOMI) around the Earth since October 2017. This mission also produces atmospheric ozone profile data which are described in detail for May 2018 to April 2023. Independent validation using ground-based reference measurements demonstrates that the operational ozone profile product mostly fully and at least partially complies with all mission requirements.
Ryan M. Stauffer, Anne M. Thompson, Debra E. Kollonige, Ninong Komala, Habib Khirzin Al-Ghazali, Dian Yudha Risdianto, Ambun Dindang, Ahmad Fairudz bin Jamaluddin, Mohan Kumar Sammathuria, Norazura Binti Zakaria, Bryan J. Johnson, and Patrick D. Cullis
Atmos. Chem. Phys., 24, 5221–5234, https://doi.org/10.5194/acp-24-5221-2024, https://doi.org/10.5194/acp-24-5221-2024, 2024
Short summary
Short summary
SHADOZ balloon-borne ozone measurements over equatorial Southeast Asia from 1998–2022 reveal that ozone increases during the early months of the year are linked to reduced convective storm activity, which typically redistributes and cleans the atmosphere of ozone. These findings challenge models to replicate the trends produced by the SHADOZ and meteorological observations and emphasize the importance of studying monthly or seasonal instead of annual changes for understanding ozone trends.
Andrea Orfanoz-Cheuquelaf, Carlo Arosio, Alexei Rozanov, Mark Weber, Annette Ladstätter-Weißenmayer, John P. Burrows, Anne M. Thompson, Ryan M. Stauffer, and Debra E. Kollonige
Atmos. Meas. Tech., 17, 1791–1809, https://doi.org/10.5194/amt-17-1791-2024, https://doi.org/10.5194/amt-17-1791-2024, 2024
Short summary
Short summary
Valuable information on the tropospheric ozone column (TrOC) can be obtained globally by combining space-borne limb and nadir measurements (limb–nadir matching, LNM). This study describes the retrieval of TrOC from the OMPS instrument (since 2012) using the LNM technique. The OMPS-LNM TrOC was compared with ozonesondes and other satellite measurements, showing a good agreement with a negative bias within 1 to 4 DU. This new dataset is suitable for pollution studies.
Herman G. J. Smit, Deniz Poyraz, Roeland Van Malderen, Anne M. Thompson, David W. Tarasick, Ryan M. Stauffer, Bryan J. Johnson, and Debra E. Kollonige
Atmos. Meas. Tech., 17, 73–112, https://doi.org/10.5194/amt-17-73-2024, https://doi.org/10.5194/amt-17-73-2024, 2024
Short summary
Short summary
This paper revisits fundamentals of ECC ozonesonde measurements to develop and characterize a methodology to correct for the fast and slow time responses using the JOSIE (Jülich Ozone Sonde Intercomparison Experiment) simulation chamber data. Comparing the new corrected ozonesonde profiles to an accurate ozone UV photometer (OPM) as reference allows us to evaluate the time response correction (TRC) method and to determine calibration functions traceable to one reference with 5 % uncertainty.
Nora Mettig, Mark Weber, Alexei Rozanov, John P. Burrows, Pepijn Veefkind, Anne M. Thompson, Ryan M. Stauffer, Thierry Leblanc, Gerard Ancellet, Michael J. Newchurch, Shi Kuang, Rigel Kivi, Matthew B. Tully, Roeland Van Malderen, Ankie Piters, Bogumil Kois, René Stübi, and Pavla Skrivankova
Atmos. Meas. Tech., 15, 2955–2978, https://doi.org/10.5194/amt-15-2955-2022, https://doi.org/10.5194/amt-15-2955-2022, 2022
Short summary
Short summary
Vertical ozone profiles from combined spectral measurements in the UV and IR spectral ranges were retrieved by using data from TROPOMI/S5P and CrIS/Suomi-NPP. The vertical resolution and accuracy of the ozone profiles are improved by combining both wavelength ranges compared to retrievals limited to UV or IR spectral data only. The advancement of our TOPAS algorithm for combined measurements is required because in the UV-only retrieval the vertical resolution in the troposphere is very limited.
Nikos Daskalakis, Laura Gallardo, Maria Kanakidou, Johann Rasmus Nüß, Camilo Menares, Roberto Rondanelli, Anne M. Thompson, and Mihalis Vrekoussis
Atmos. Chem. Phys., 22, 4075–4099, https://doi.org/10.5194/acp-22-4075-2022, https://doi.org/10.5194/acp-22-4075-2022, 2022
Short summary
Short summary
Forest fires emit carbon monoxide (CO) that can be transported into the atmosphere far from the sources and reacts to produce ozone (O3) that affects climate, ecosystems and health. O3 is also produced in the stratosphere and can be transported downwards. Using a global numerical model, we found that forest fires can affect CO and O3 even in the South Pacific, the most pristine region of the global ocean, but transport from the stratosphere is a more important O3 source than fires in the region.
Daan Hubert, Klaus-Peter Heue, Jean-Christopher Lambert, Tijl Verhoelst, Marc Allaart, Steven Compernolle, Patrick D. Cullis, Angelika Dehn, Christian Félix, Bryan J. Johnson, Arno Keppens, Debra E. Kollonige, Christophe Lerot, Diego Loyola, Matakite Maata, Sukarni Mitro, Maznorizan Mohamad, Ankie Piters, Fabian Romahn, Henry B. Selkirk, Francisco R. da Silva, Ryan M. Stauffer, Anne M. Thompson, J. Pepijn Veefkind, Holger Vömel, Jacquelyn C. Witte, and Claus Zehner
Atmos. Meas. Tech., 14, 7405–7433, https://doi.org/10.5194/amt-14-7405-2021, https://doi.org/10.5194/amt-14-7405-2021, 2021
Short summary
Short summary
We assess the first 2 years of TROPOMI tropical tropospheric ozone column data. Comparisons to reference measurements by ozonesonde and satellite sensors show that TROPOMI bias (−0.1 to +2.3 DU) and precision (1.5 to 2.5 DU) meet mission requirements. Potential causes of bias and its spatio-temporal structure are discussed, as well as ways to identify sampling errors. Our analysis of known geophysical patterns demonstrates the improved performance of TROPOMI with respect to its predecessors.
Nora Mettig, Mark Weber, Alexei Rozanov, Carlo Arosio, John P. Burrows, Pepijn Veefkind, Anne M. Thompson, Richard Querel, Thierry Leblanc, Sophie Godin-Beekmann, Rigel Kivi, and Matthew B. Tully
Atmos. Meas. Tech., 14, 6057–6082, https://doi.org/10.5194/amt-14-6057-2021, https://doi.org/10.5194/amt-14-6057-2021, 2021
Short summary
Short summary
TROPOMI is a nadir-viewing satellite that has observed global atmospheric trace gases at unprecedented spatial resolution since 2017. The retrieval of ozone profiles with high accuracy has been demonstrated using the TOPAS (Tikhonov regularised Ozone Profile retrievAl with SCIATRAN) algorithm and applying appropriate spectral corrections to TROPOMI UV data. Ozone profiles from TROPOMI were compared to ozonesonde and lidar profiles, showing an agreement to within 5 % in the stratosphere.
Jianfeng Li, Yuhang Wang, Ruixiong Zhang, Charles Smeltzer, Andrew Weinheimer, Jay Herman, K. Folkert Boersma, Edward A. Celarier, Russell W. Long, James J. Szykman, Ruben Delgado, Anne M. Thompson, Travis N. Knepp, Lok N. Lamsal, Scott J. Janz, Matthew G. Kowalewski, Xiong Liu, and Caroline R. Nowlan
Atmos. Chem. Phys., 21, 11133–11160, https://doi.org/10.5194/acp-21-11133-2021, https://doi.org/10.5194/acp-21-11133-2021, 2021
Short summary
Short summary
Comprehensive evaluations of simulated diurnal cycles of NO2 and NOy concentrations, vertical profiles, and tropospheric vertical column densities at two different resolutions with various measurements during the DISCOVER-AQ 2011 campaign show potential distribution biases of NOx emissions in the National Emissions Inventory 2011 at both 36 and 4 km resolutions, providing another possible explanation for the overestimation of model results.
Holger Vömel, Herman G. J. Smit, David Tarasick, Bryan Johnson, Samuel J. Oltmans, Henry Selkirk, Anne M. Thompson, Ryan M. Stauffer, Jacquelyn C. Witte, Jonathan Davies, Roeland van Malderen, Gary A. Morris, Tatsumi Nakano, and Rene Stübi
Atmos. Meas. Tech., 13, 5667–5680, https://doi.org/10.5194/amt-13-5667-2020, https://doi.org/10.5194/amt-13-5667-2020, 2020
Short summary
Short summary
The time response of electrochemical concentration cell (ECC) ozonesondes points to at least two distinct reaction pathways with time constants of approximately 20 s and 25 min. Properly considering these time constants eliminates the need for a poorly defined "background" and allows reducing ad hoc corrections based on laboratory tests. This reduces the uncertainty of ECC ozonesonde measurements throughout the profile and especially in regions of low ozone and strong gradients of ozone.
Ilann Bourgeois, Jeff Peischl, Chelsea R. Thompson, Kenneth C. Aikin, Teresa Campos, Hannah Clark, Róisín Commane, Bruce Daube, Glenn W. Diskin, James W. Elkins, Ru-Shan Gao, Audrey Gaudel, Eric J. Hintsa, Bryan J. Johnson, Rigel Kivi, Kathryn McKain, Fred L. Moore, David D. Parrish, Richard Querel, Eric Ray, Ricardo Sánchez, Colm Sweeney, David W. Tarasick, Anne M. Thompson, Valérie Thouret, Jacquelyn C. Witte, Steve C. Wofsy, and Thomas B. Ryerson
Atmos. Chem. Phys., 20, 10611–10635, https://doi.org/10.5194/acp-20-10611-2020, https://doi.org/10.5194/acp-20-10611-2020, 2020
John T. Sullivan, Thomas J. McGee, Ryan M. Stauffer, Anne M. Thompson, Andrew Weinheimer, Christoph Knote, Scott Janz, Armin Wisthaler, Russell Long, James Szykman, Jinsoo Park, Youngjae Lee, Saewung Kim, Daun Jeong, Dianne Sanchez, Laurence Twigg, Grant Sumnicht, Travis Knepp, and Jason R. Schroeder
Atmos. Chem. Phys., 19, 5051–5067, https://doi.org/10.5194/acp-19-5051-2019, https://doi.org/10.5194/acp-19-5051-2019, 2019
Short summary
Short summary
During the May–June 2016 International Cooperative Air Quality Field Study in Korea (KORUS-AQ), pollution reached the remote Taehwa Research Forest (TRF) site. Two case studies are examined and observations clearly identify TRF and the surrounding rural areas as long-term receptor sites for severe urban pollution events. In summary, domestic emissions may be causing more pollution than by transboundary pathways, which have been historically believed to be the major source of air pollution.
Jerry R. Ziemke, Luke D. Oman, Sarah A. Strode, Anne R. Douglass, Mark A. Olsen, Richard D. McPeters, Pawan K. Bhartia, Lucien Froidevaux, Gordon J. Labow, Jacquie C. Witte, Anne M. Thompson, David P. Haffner, Natalya A. Kramarova, Stacey M. Frith, Liang-Kang Huang, Glen R. Jaross, Colin J. Seftor, Mathew T. Deland, and Steven L. Taylor
Atmos. Chem. Phys., 19, 3257–3269, https://doi.org/10.5194/acp-19-3257-2019, https://doi.org/10.5194/acp-19-3257-2019, 2019
Short summary
Short summary
Both a 38-year merged satellite record of tropospheric ozone from TOMS/OMI/MLS/OMPS and a MERRA-2 GMI model simulation show large increases of 6–7 Dobson units from the Near East to India–East Asia and eastward over the Pacific. These increases in tropospheric ozone are attributed to increases in pollution over the region over the last several decades. Secondary 38-year increases of 4–5 Dobson units with both GMI model and satellite measurements occur over central African–tropical Atlantic.
Tracey Leah Laban, Pieter Gideon van Zyl, Johan Paul Beukes, Ville Vakkari, Kerneels Jaars, Nadine Borduas-Dedekind, Miroslav Josipovic, Anne Mee Thompson, Markku Kulmala, and Lauri Laakso
Atmos. Chem. Phys., 18, 15491–15514, https://doi.org/10.5194/acp-18-15491-2018, https://doi.org/10.5194/acp-18-15491-2018, 2018
Short summary
Short summary
Surface O3 was measured at four sites in the north-eastern interior of South Africa, which revealed that O3 is a regional problem in continental South Africa, with elevated O3 levels found at rural background and industrial sites. Increased O3 concentrations were associated with high CO levels predominantly related to regional biomass burning, while the O3 production regime was established to be predominantly VOC limited. Increased O3 is associated with strong seasonality of precursor sources.
Dejian Fu, Susan S. Kulawik, Kazuyuki Miyazaki, Kevin W. Bowman, John R. Worden, Annmarie Eldering, Nathaniel J. Livesey, Joao Teixeira, Fredrick W. Irion, Robert L. Herman, Gregory B. Osterman, Xiong Liu, Pieternel F. Levelt, Anne M. Thompson, and Ming Luo
Atmos. Meas. Tech., 11, 5587–5605, https://doi.org/10.5194/amt-11-5587-2018, https://doi.org/10.5194/amt-11-5587-2018, 2018
Wenfu Tang, Avelino F. Arellano, Joshua P. DiGangi, Yonghoon Choi, Glenn S. Diskin, Anna Agustí-Panareda, Mark Parrington, Sebastien Massart, Benjamin Gaubert, Youngjae Lee, Danbi Kim, Jinsang Jung, Jinkyu Hong, Je-Woo Hong, Yugo Kanaya, Mindo Lee, Ryan M. Stauffer, Anne M. Thompson, James H. Flynn, and Jung-Hun Woo
Atmos. Chem. Phys., 18, 11007–11030, https://doi.org/10.5194/acp-18-11007-2018, https://doi.org/10.5194/acp-18-11007-2018, 2018
Elpida Leventidou, Mark Weber, Kai-Uwe Eichmann, John P. Burrows, Klaus-Peter Heue, Anne M. Thompson, and Bryan J. Johnson
Atmos. Chem. Phys., 18, 9189–9205, https://doi.org/10.5194/acp-18-9189-2018, https://doi.org/10.5194/acp-18-9189-2018, 2018
Short summary
Short summary
Three individual tropical tropospheric ozone (TTCO) datasets (1996–2015) retrieved with the convective-cloud differential method (Leventidou et al., 2016) have been harmonised in order to study the global and regional TTCO trends. The trends range between −4 to 4 DU per decade testing six different merging scenarios. No trend has been found for the global tropics using the preferred scenario. It is concluded that harmonisation is one of the major sources of uncertainty in the trend estimates.
Chance W. Sterling, Bryan J. Johnson, Samuel J. Oltmans, Herman G. J. Smit, Allen F. Jordan, Patrick D. Cullis, Emrys G. Hall, Anne M. Thompson, and Jacquelyn C. Witte
Atmos. Meas. Tech., 11, 3661–3687, https://doi.org/10.5194/amt-11-3661-2018, https://doi.org/10.5194/amt-11-3661-2018, 2018
Short summary
Short summary
The electrochemical concentration cell ozonesonde is a balloon-borne instrument that measures ozone to an altitude of ~30 km. This work summarizes the National Oceanic and Atmospheric Administration's 50+ year, eight-site ozonesonde network history, the processing techniques utilized to account for instrumental changes, and the uncertainty of the measurement. The ozonesonde measurements were compared to satellite measurements and agreed well. This important data set is more useful and robust.
Martine De Mazière, Anne M. Thompson, Michael J. Kurylo, Jeannette D. Wild, Germar Bernhard, Thomas Blumenstock, Geir O. Braathen, James W. Hannigan, Jean-Christopher Lambert, Thierry Leblanc, Thomas J. McGee, Gerald Nedoluha, Irina Petropavlovskikh, Gunther Seckmeyer, Paul C. Simon, Wolfgang Steinbrecht, and Susan E. Strahan
Atmos. Chem. Phys., 18, 4935–4964, https://doi.org/10.5194/acp-18-4935-2018, https://doi.org/10.5194/acp-18-4935-2018, 2018
Short summary
Short summary
This paper serves as an introduction to the special issue "Twenty-five years of operations of the Network for the Detection of Atmospheric Composition Change (NDACC)". It describes the origins of the network, its actual status, and some perspectives for its future evolution in the context of atmospheric sciences.
Katherine R. Travis, Daniel J. Jacob, Christoph A. Keller, Shi Kuang, Jintai Lin, Michael J. Newchurch, and Anne M. Thompson
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2017-596, https://doi.org/10.5194/acp-2017-596, 2017
Preprint retracted
Short summary
Short summary
Models severely overestimate surface ozone in the Southeast US during summertime which has implications for the design of air quality regulations. We use a model (GEOS-Chem) to interpret ozone observations from a suite of observations taken during August–September 2013. The model is unbiased relative to observations below 1 km but is biased high at the surface. We attribute this bias to model representation error, an underestimate in low-cloud, and insufficient treatment of vertical mixing.
Guanyu Huang, Xiong Liu, Kelly Chance, Kai Yang, Pawan K. Bhartia, Zhaonan Cai, Marc Allaart, Gérard Ancellet, Bertrand Calpini, Gerrie J. R. Coetzee, Emilio Cuevas-Agulló, Manuel Cupeiro, Hugo De Backer, Manvendra K. Dubey, Henry E. Fuelberg, Masatomo Fujiwara, Sophie Godin-Beekmann, Tristan J. Hall, Bryan Johnson, Everette Joseph, Rigel Kivi, Bogumil Kois, Ninong Komala, Gert König-Langlo, Giovanni Laneve, Thierry Leblanc, Marion Marchand, Kenneth R. Minschwaner, Gary Morris, Michael J. Newchurch, Shin-Ya Ogino, Nozomu Ohkawara, Ankie J. M. Piters, Françoise Posny, Richard Querel, Rinus Scheele, Frank J. Schmidlin, Russell C. Schnell, Otto Schrems, Henry Selkirk, Masato Shiotani, Pavla Skrivánková, René Stübi, Ghassan Taha, David W. Tarasick, Anne M. Thompson, Valérie Thouret, Matthew B. Tully, Roeland Van Malderen, Holger Vömel, Peter von der Gathen, Jacquelyn C. Witte, and Margarita Yela
Atmos. Meas. Tech., 10, 2455–2475, https://doi.org/10.5194/amt-10-2455-2017, https://doi.org/10.5194/amt-10-2455-2017, 2017
Short summary
Short summary
It is essential to understand the data quality of +10-year OMI ozone product and impacts of the “row anomaly” (RA). We validate the OMI Ozone Profile (PROFOZ) product from Oct 2004 to Dec 2014 against ozonesonde observations globally. Generally, OMI has good agreement with ozonesondes. The spatiotemporal variation of retrieval performance suggests the need to improve OMI’s radiometric calibration especially during the post-RA period to maintain the long-term stability.
J. Aschmann, J. P. Burrows, C. Gebhardt, A. Rozanov, R. Hommel, M. Weber, and A. M. Thompson
Atmos. Chem. Phys., 14, 12803–12814, https://doi.org/10.5194/acp-14-12803-2014, https://doi.org/10.5194/acp-14-12803-2014, 2014
Short summary
Short summary
This study compares observations and simulation results of ozone in the lower tropical stratosphere. It shows that ozone in this region decreased from 1985 up to about 2002, which is consistent with an increase in tropical upwelling predicted by climate models. However, the decrease effectively stops after 2002, indicating that significant changes in tropical upwelling have occurred. The most important factor appears to be that the vertical ascent in the tropics is no longer accelerating.
C. Gebhardt, A. Rozanov, R. Hommel, M. Weber, H. Bovensmann, J. P. Burrows, D. Degenstein, L. Froidevaux, and A. M. Thompson
Atmos. Chem. Phys., 14, 831–846, https://doi.org/10.5194/acp-14-831-2014, https://doi.org/10.5194/acp-14-831-2014, 2014
R. M. Stauffer, G. A. Morris, A. M. Thompson, E. Joseph, G. J. R. Coetzee, and N. R. Nalli
Atmos. Meas. Tech., 7, 65–79, https://doi.org/10.5194/amt-7-65-2014, https://doi.org/10.5194/amt-7-65-2014, 2014
Roeland Van Malderen, Anne M. Thompson, Debra E. Kollonige, Ryan M. Stauffer, Herman G. J. Smit, Eliane Maillard Barras, Corinne Vigouroux, Irina Petropavlovskikh, Thierry Leblanc, Valérie Thouret, Pawel Wolff, Peter Effertz, David W. Tarasick, Deniz Poyraz, Gérard Ancellet, Marie-Renée De Backer, Stéphanie Evan, Victoria Flood, Matthias M. Frey, James W. Hannigan, José L. Hernandez, Marco Iarlori, Bryan J. Johnson, Nicholas Jones, Rigel Kivi, Emmanuel Mahieu, Glen McConville, Katrin Müller, Tomoo Nagahama, Justus Notholt, Ankie Piters, Natalia Prats, Richard Querel, Dan Smale, Wolfgang Steinbrecht, Kimberly Strong, and Ralf Sussmann
Atmos. Chem. Phys., 25, 7187–7225, https://doi.org/10.5194/acp-25-7187-2025, https://doi.org/10.5194/acp-25-7187-2025, 2025
Short summary
Short summary
Tropospheric ozone is an important greenhouse gas and is an air pollutant. The time variability of tropospheric ozone is mainly driven by anthropogenic emissions. In this paper, we study the distribution and time variability of ozone from harmonized ground-based observations from five different measurement techniques. Our findings provide clear standard references for atmospheric models and evolving tropospheric ozone satellite data for the 2000–2022 period.
Sergey Khaykin, Slimane Bekki, Sophie Godin-Beekmann, Michael D. Fromm, Philippe Goloub, Qiaoyun Hu, Béatrice Josse, Alexandra Laeng, Mehdi Meziane, David A. Peterson, Sophie Pelletier, and Valérie Thouret
EGUsphere, https://doi.org/10.5194/egusphere-2025-3152, https://doi.org/10.5194/egusphere-2025-3152, 2025
This preprint is open for discussion and under review for Atmospheric Chemistry and Physics (ACP).
Short summary
Short summary
In 2023, massive wildfires in Canada injected huge amounts of smoke into the atmosphere. Surprisingly, despite their intensity, the smoke didn’t rise very high but lingered at flight cruising altitudes, causing widespread pollution. This study shows how two different pathways lifted smoke into the lower stratosphere and reveals new insights into how wildfires affect air quality and climate, challenging what we thought we knew about fire and atmospheric impacts.
Yann Cohen, Didier Hauglustaine, Nicolas Bellouin, Marianne Tronstad Lund, Sigrun Matthes, Agnieszka Skowron, Robin Thor, Ulrich Bundke, Andreas Petzold, Susanne Rohs, Valérie Thouret, Andreas Zahn, and Helmut Ziereis
Atmos. Chem. Phys., 25, 5793–5836, https://doi.org/10.5194/acp-25-5793-2025, https://doi.org/10.5194/acp-25-5793-2025, 2025
Short summary
Short summary
The chemical composition of the atmosphere near the tropopause is a key parameter for evaluating the climate impact of subsonic aviation pollutants. This study uses in situ data collected aboard passenger aircraft to assess the ability of four chemistry–climate models to reproduce (bi-)decadal climatologies of ozone, carbon monoxide, water vapour, and reactive nitrogen in this region. The models reproduce the very distinct ozone seasonality in the upper troposphere and in the lower stratosphere well.
Min Huang, Gregory R. Carmichael, Kevin W. Bowman, Isabelle De Smedt, Andreas Colliander, Michael H. Cosh, Sujay V. Kumar, Alex B. Guenther, Scott J. Janz, Ryan M. Stauffer, Anne M. Thompson, Niko M. Fedkin, Robert J. Swap, John D. Bolten, and Alicia T. Joseph
Atmos. Chem. Phys., 25, 1449–1476, https://doi.org/10.5194/acp-25-1449-2025, https://doi.org/10.5194/acp-25-1449-2025, 2025
Short summary
Short summary
We use model simulations along with multiplatform, multidisciplinary observations and a range of analysis methods to estimate and understand the distributions, temporal changes, and impacts of reactive nitrogen and ozone over the most populous US region that has undergone significant environmental changes. Deposition, biogenic emissions, and extra-regional sources have been playing increasingly important roles in controlling pollutant budgets in this area as local anthropogenic emissions drop.
Anne M. Thompson, Ryan M. Stauffer, Debra E. Kollonige, Jerald R. Ziemke, Maria Cazorla, Pawel Wolff, and Bastien Sauvage
EGUsphere, https://doi.org/10.5194/egusphere-2024-3761, https://doi.org/10.5194/egusphere-2024-3761, 2025
Short summary
Short summary
This paper uses tropical ozone profiles from balloon borne instruments and aircraft to show that ozone in the free troposphere is not growing fast except over equatorial SE Asia.
Roeland Van Malderen, Zhou Zang, Kai-Lan Chang, Robin Björklund, Owen R. Cooper, Jane Liu, Eliane Maillard Barras, Corinne Vigouroux, Irina Petropavlovskikh, Thierry Leblanc, Valérie Thouret, Pawel Wolff, Peter Effertz, Audrey Gaudel, David W. Tarasick, Herman G. J. Smit, Anne M. Thompson, Ryan M. Stauffer, Debra E. Kollonige, Deniz Poyraz, Gérard Ancellet, Marie-Renée De Backer, Matthias M. Frey, James W. Hannigan, José L. Hernandez, Bryan J. Johnson, Nicholas Jones, Rigel Kivi, Emmanuel Mahieu, Isamu Morino, Glen McConville, Katrin Müller, Isao Murata, Justus Notholt, Ankie Piters, Maxime Prignon, Richard Querel, Vincenzo Rizi, Dan Smale, Wolfgang Steinbrecht, Kimberly Strong, and Ralf Sussmann
EGUsphere, https://doi.org/10.5194/egusphere-2024-3745, https://doi.org/10.5194/egusphere-2024-3745, 2025
Short summary
Short summary
Tropospheric ozone is an important greenhouse gas and an air pollutant, whose distribution and time variability is mainly governed by anthropogenic emissions and dynamics. In this paper, we assess regional trends of tropospheric ozone column amounts, based on two different approaches of merging or synthesizing ground-based observations and their trends within specific regions. Our findings clearly demonstrate regional trend differences, but also consistently higher pre- than post-COVID trends.
Herman G.J. Smit, Torben Galle, Romain Blot, Florian Obersteiner, Philippe Nédélec, Andreas Zahn, Jean-Marc Cousin, Ulrich Bundke, Andreas Petzold, Valerie Thouret, and Hannah Clark
EGUsphere, https://doi.org/10.5194/egusphere-2024-3760, https://doi.org/10.5194/egusphere-2024-3760, 2025
Short summary
Short summary
The two ozone instruments of IAGOS (In-service Aircraft for a Global Observation System) have been compared with the Ozone PhotoMeter (OPM) of the World Calibration Center of Ozone Sondes (WCCOS) in an atmospheric simulation chamber under realistic flight conditions of pressure, temperature, and ozone concentrations. The two IAGOS-instruments showed good agreement with the OPM within 5–6 %. The observed differences are small but systematic and reproducible during the intercomparison.
Thibaut Lebourgeois, Bastien Sauvage, Pawel Wolff, Béatrice Josse, Virginie Marécal, Yasmine Bennouna, Romain Blot, Damien Boulanger, Hannah Clark, Jean-Marc Cousin, Philippe Nedelec, and Valérie Thouret
Atmos. Chem. Phys., 24, 13975–14004, https://doi.org/10.5194/acp-24-13975-2024, https://doi.org/10.5194/acp-24-13975-2024, 2024
Short summary
Short summary
Our study examines intense-carbon-monoxide (CO) pollution events measured by commercial aircraft from the In-service Aircraft for a Global Observing System (IAGOS) research infrastructure. We combine these measurements with the SOFT-IO model to trace the origin of the observed CO. A comprehensive analysis of the geographical origin, source type, seasonal variation, and ozone levels of these pollution events is provided.
Zhou Zang, Jane Liu, David Tarasick, Omid Moeini, Jianchun Bian, Jinqiang Zhang, Anne M. Thompson, Roeland Van Malderen, Herman G. J. Smit, Ryan M. Stauffer, Bryan J. Johnson, and Debra E. Kollonige
Atmos. Chem. Phys., 24, 13889–13912, https://doi.org/10.5194/acp-24-13889-2024, https://doi.org/10.5194/acp-24-13889-2024, 2024
Short summary
Short summary
The Trajectory-mapped Ozonesonde dataset for the Stratosphere and Troposphere (TOST) provides a global-scale, long-term ozone climatology that is horizontally and vertically resolved. In this study, we improved, updated and validated TOST from 1970 to 2021. Based on this TOST dataset, we characterized global ozone variations spatially in both the troposphere and stratosphere and temporally by season and decade. We also showed a stagnant lower stratospheric ozone variation since the late 1990s.
Jiansheng Zou, Kaley A. Walker, Patrick E. Sheese, Chris D. Boone, Ryan M. Stauffer, Anne M. Thompson, and David W. Tarasick
Atmos. Meas. Tech., 17, 6983–7005, https://doi.org/10.5194/amt-17-6983-2024, https://doi.org/10.5194/amt-17-6983-2024, 2024
Short summary
Short summary
Ozone measurements from the ACE-FTS satellite instrument have been compared to worldwide balloon-borne ozonesonde profiles using pairs of closely spaced profiles and monthly averaged profiles. ACE-FTS typically measures more ozone in the stratosphere by up to 10 %. The long-term stability of the ACE-FTS ozone data is good, exhibiting small (but non-significant) drifts of less than 3 % per decade in the stratosphere. Lower in the profiles, the calculated drifts are larger (up to 10 % per decade).
Swathi Maratt Satheesan, Kai-Uwe Eichmann, John P. Burrows, Mark Weber, Ryan Stauffer, Anne M. Thompson, and Debra Kollonige
Atmos. Meas. Tech., 17, 6459–6484, https://doi.org/10.5194/amt-17-6459-2024, https://doi.org/10.5194/amt-17-6459-2024, 2024
Short summary
Short summary
CHORA, an advanced cloud convective differential technique, enhances the accuracy of tropospheric-ozone retrievals. Unlike the traditional Pacific cloud reference sector scheme, CHORA introduces a local-cloud reference sector and an alternative approach (CLCT) for precision. Analysing monthly averaged TROPOMI data from 2018 to 2022 and validating with SHADOZ ozonesonde data, CLCT outperforms other methods and so is the preferred choice, especially in future geostationary satellite missions.
Audrey Gaudel, Ilann Bourgeois, Meng Li, Kai-Lan Chang, Jerald Ziemke, Bastien Sauvage, Ryan M. Stauffer, Anne M. Thompson, Debra E. Kollonige, Nadia Smith, Daan Hubert, Arno Keppens, Juan Cuesta, Klaus-Peter Heue, Pepijn Veefkind, Kenneth Aikin, Jeff Peischl, Chelsea R. Thompson, Thomas B. Ryerson, Gregory J. Frost, Brian C. McDonald, and Owen R. Cooper
Atmos. Chem. Phys., 24, 9975–10000, https://doi.org/10.5194/acp-24-9975-2024, https://doi.org/10.5194/acp-24-9975-2024, 2024
Short summary
Short summary
The study examines tropical tropospheric ozone changes. In situ data from 1994–2019 display increased ozone, notably over India, Southeast Asia, and Malaysia and Indonesia. Sparse in situ data limit trend detection for the 15-year period. In situ and satellite data, with limited sampling, struggle to consistently detect trends. Continuous observations are vital over the tropical Pacific Ocean, Indian Ocean, western Africa, and South Asia for accurate ozone trend estimation in these regions.
Henk Eskes, Athanasios Tsikerdekis, Melanie Ades, Mihai Alexe, Anna Carlin Benedictow, Yasmine Bennouna, Lewis Blake, Idir Bouarar, Simon Chabrillat, Richard Engelen, Quentin Errera, Johannes Flemming, Sebastien Garrigues, Jan Griesfeller, Vincent Huijnen, Luka Ilić, Antje Inness, John Kapsomenakis, Zak Kipling, Bavo Langerock, Augustin Mortier, Mark Parrington, Isabelle Pison, Mikko Pitkänen, Samuel Remy, Andreas Richter, Anja Schoenhardt, Michael Schulz, Valerie Thouret, Thorsten Warneke, Christos Zerefos, and Vincent-Henri Peuch
Atmos. Chem. Phys., 24, 9475–9514, https://doi.org/10.5194/acp-24-9475-2024, https://doi.org/10.5194/acp-24-9475-2024, 2024
Short summary
Short summary
The Copernicus Atmosphere Monitoring Service (CAMS) provides global analyses and forecasts of aerosols and trace gases in the atmosphere. On 27 June 2023 a major upgrade, Cy48R1, became operational. Comparisons with in situ, surface remote sensing, aircraft, and balloon and satellite observations show that the new CAMS system is a significant improvement. The results quantify the skill of CAMS to forecast impactful events, such as wildfires, dust storms and air pollution peaks.
Kuo-Ying Wang, Philippe Nedelec, Valerie Thouret, Hannah Clark, Andreas Wahner, and Andreas Petzold
EGUsphere, https://doi.org/10.5194/egusphere-2024-2414, https://doi.org/10.5194/egusphere-2024-2414, 2024
Short summary
Short summary
We use routine in-service commercial passenger airplanes Airbus A340 and A330 to collect air pollutants in the upper troposphere. The beauty in using commercial airplanes is that these commercial airplanes, like taxi on the ground, keep flying all the time. We find that short-lived air pollutants are very sensitive to ground-level emissions. Effective regulation in ground-level emissions can help to reduce air pollution in the upper troposphere.
Arno Keppens, Serena Di Pede, Daan Hubert, Jean-Christopher Lambert, Pepijn Veefkind, Maarten Sneep, Johan De Haan, Mark ter Linden, Thierry Leblanc, Steven Compernolle, Tijl Verhoelst, José Granville, Oindrila Nath, Ann Mari Fjæraa, Ian Boyd, Sander Niemeijer, Roeland Van Malderen, Herman G. J. Smit, Valentin Duflot, Sophie Godin-Beekmann, Bryan J. Johnson, Wolfgang Steinbrecht, David W. Tarasick, Debra E. Kollonige, Ryan M. Stauffer, Anne M. Thompson, Angelika Dehn, and Claus Zehner
Atmos. Meas. Tech., 17, 3969–3993, https://doi.org/10.5194/amt-17-3969-2024, https://doi.org/10.5194/amt-17-3969-2024, 2024
Short summary
Short summary
The Sentinel-5P satellite operated by the European Space Agency has carried the TROPOspheric Monitoring Instrument (TROPOMI) around the Earth since October 2017. This mission also produces atmospheric ozone profile data which are described in detail for May 2018 to April 2023. Independent validation using ground-based reference measurements demonstrates that the operational ozone profile product mostly fully and at least partially complies with all mission requirements.
Andreas Petzold, Ulrich Bundke, Anca Hienola, Paolo Laj, Cathrine Lund Myhre, Alex Vermeulen, Angeliki Adamaki, Werner Kutsch, Valerie Thouret, Damien Boulanger, Markus Fiebig, Markus Stocker, Zhiming Zhao, and Ari Asmi
Atmos. Chem. Phys., 24, 5369–5388, https://doi.org/10.5194/acp-24-5369-2024, https://doi.org/10.5194/acp-24-5369-2024, 2024
Short summary
Short summary
Easy and fast access to long-term and high-quality observational data is recognised as fundamental to environmental research and the development of climate forecasting and assessment services. We discuss the potential new directions in atmospheric sciences offered by the atmosphere-centric European research infrastructures ACTRIS, IAGOS, and ICOS, building on their capabilities for standardised provision of data through open access combined with tools and methods of data-intensive science.
Ryan M. Stauffer, Anne M. Thompson, Debra E. Kollonige, Ninong Komala, Habib Khirzin Al-Ghazali, Dian Yudha Risdianto, Ambun Dindang, Ahmad Fairudz bin Jamaluddin, Mohan Kumar Sammathuria, Norazura Binti Zakaria, Bryan J. Johnson, and Patrick D. Cullis
Atmos. Chem. Phys., 24, 5221–5234, https://doi.org/10.5194/acp-24-5221-2024, https://doi.org/10.5194/acp-24-5221-2024, 2024
Short summary
Short summary
SHADOZ balloon-borne ozone measurements over equatorial Southeast Asia from 1998–2022 reveal that ozone increases during the early months of the year are linked to reduced convective storm activity, which typically redistributes and cleans the atmosphere of ozone. These findings challenge models to replicate the trends produced by the SHADOZ and meteorological observations and emphasize the importance of studying monthly or seasonal instead of annual changes for understanding ozone trends.
Andrea Orfanoz-Cheuquelaf, Carlo Arosio, Alexei Rozanov, Mark Weber, Annette Ladstätter-Weißenmayer, John P. Burrows, Anne M. Thompson, Ryan M. Stauffer, and Debra E. Kollonige
Atmos. Meas. Tech., 17, 1791–1809, https://doi.org/10.5194/amt-17-1791-2024, https://doi.org/10.5194/amt-17-1791-2024, 2024
Short summary
Short summary
Valuable information on the tropospheric ozone column (TrOC) can be obtained globally by combining space-borne limb and nadir measurements (limb–nadir matching, LNM). This study describes the retrieval of TrOC from the OMPS instrument (since 2012) using the LNM technique. The OMPS-LNM TrOC was compared with ozonesondes and other satellite measurements, showing a good agreement with a negative bias within 1 to 4 DU. This new dataset is suitable for pollution studies.
Herman G. J. Smit, Deniz Poyraz, Roeland Van Malderen, Anne M. Thompson, David W. Tarasick, Ryan M. Stauffer, Bryan J. Johnson, and Debra E. Kollonige
Atmos. Meas. Tech., 17, 73–112, https://doi.org/10.5194/amt-17-73-2024, https://doi.org/10.5194/amt-17-73-2024, 2024
Short summary
Short summary
This paper revisits fundamentals of ECC ozonesonde measurements to develop and characterize a methodology to correct for the fast and slow time responses using the JOSIE (Jülich Ozone Sonde Intercomparison Experiment) simulation chamber data. Comparing the new corrected ozonesonde profiles to an accurate ozone UV photometer (OPM) as reference allows us to evaluate the time response correction (TRC) method and to determine calibration functions traceable to one reference with 5 % uncertainty.
Yann Cohen, Didier Hauglustaine, Bastien Sauvage, Susanne Rohs, Patrick Konjari, Ulrich Bundke, Andreas Petzold, Valérie Thouret, Andreas Zahn, and Helmut Ziereis
Atmos. Chem. Phys., 23, 14973–15009, https://doi.org/10.5194/acp-23-14973-2023, https://doi.org/10.5194/acp-23-14973-2023, 2023
Short summary
Short summary
The upper troposphere–lower stratosphere (UTLS) is a key region regarding the lower atmospheric composition. This study consists of a comprehensive evaluation of an up-to-date chemistry–climate model in this layer, using regular in situ measurements based on passenger aircraft. For this purpose, a specific software (Interpol-IAGOS) has been updated and made publicly available. The model reproduces the carbon monoxide peaks due to biomass burning over the continental tropics particularly well.
Maria Tsivlidou, Bastien Sauvage, Yasmine Bennouna, Romain Blot, Damien Boulanger, Hannah Clark, Eric Le Flochmoën, Philippe Nédélec, Valérie Thouret, Pawel Wolff, and Brice Barret
Atmos. Chem. Phys., 23, 14039–14063, https://doi.org/10.5194/acp-23-14039-2023, https://doi.org/10.5194/acp-23-14039-2023, 2023
Short summary
Short summary
The tropics are a region where the ozone increase has been most apparent since 1980 and where observations are sparse. Using aircraft, satellite, and model data, we document the characteristics of tropospheric ozone and CO over the whole tropics for the last 2 decades. We explore the origin of the observed CO anomalies and investigate transport processes driving the tropical CO and O3 distribution. Our study highlights the importance of anthropogenic emissions, mostly over the northern tropics.
Nora Mettig, Mark Weber, Alexei Rozanov, John P. Burrows, Pepijn Veefkind, Anne M. Thompson, Ryan M. Stauffer, Thierry Leblanc, Gerard Ancellet, Michael J. Newchurch, Shi Kuang, Rigel Kivi, Matthew B. Tully, Roeland Van Malderen, Ankie Piters, Bogumil Kois, René Stübi, and Pavla Skrivankova
Atmos. Meas. Tech., 15, 2955–2978, https://doi.org/10.5194/amt-15-2955-2022, https://doi.org/10.5194/amt-15-2955-2022, 2022
Short summary
Short summary
Vertical ozone profiles from combined spectral measurements in the UV and IR spectral ranges were retrieved by using data from TROPOMI/S5P and CrIS/Suomi-NPP. The vertical resolution and accuracy of the ozone profiles are improved by combining both wavelength ranges compared to retrievals limited to UV or IR spectral data only. The advancement of our TOPAS algorithm for combined measurements is required because in the UV-only retrieval the vertical resolution in the troposphere is very limited.
Nikos Daskalakis, Laura Gallardo, Maria Kanakidou, Johann Rasmus Nüß, Camilo Menares, Roberto Rondanelli, Anne M. Thompson, and Mihalis Vrekoussis
Atmos. Chem. Phys., 22, 4075–4099, https://doi.org/10.5194/acp-22-4075-2022, https://doi.org/10.5194/acp-22-4075-2022, 2022
Short summary
Short summary
Forest fires emit carbon monoxide (CO) that can be transported into the atmosphere far from the sources and reacts to produce ozone (O3) that affects climate, ecosystems and health. O3 is also produced in the stratosphere and can be transported downwards. Using a global numerical model, we found that forest fires can affect CO and O3 even in the South Pacific, the most pristine region of the global ocean, but transport from the stratosphere is a more important O3 source than fires in the region.
Daan Hubert, Klaus-Peter Heue, Jean-Christopher Lambert, Tijl Verhoelst, Marc Allaart, Steven Compernolle, Patrick D. Cullis, Angelika Dehn, Christian Félix, Bryan J. Johnson, Arno Keppens, Debra E. Kollonige, Christophe Lerot, Diego Loyola, Matakite Maata, Sukarni Mitro, Maznorizan Mohamad, Ankie Piters, Fabian Romahn, Henry B. Selkirk, Francisco R. da Silva, Ryan M. Stauffer, Anne M. Thompson, J. Pepijn Veefkind, Holger Vömel, Jacquelyn C. Witte, and Claus Zehner
Atmos. Meas. Tech., 14, 7405–7433, https://doi.org/10.5194/amt-14-7405-2021, https://doi.org/10.5194/amt-14-7405-2021, 2021
Short summary
Short summary
We assess the first 2 years of TROPOMI tropical tropospheric ozone column data. Comparisons to reference measurements by ozonesonde and satellite sensors show that TROPOMI bias (−0.1 to +2.3 DU) and precision (1.5 to 2.5 DU) meet mission requirements. Potential causes of bias and its spatio-temporal structure are discussed, as well as ways to identify sampling errors. Our analysis of known geophysical patterns demonstrates the improved performance of TROPOMI with respect to its predecessors.
Hannah Clark, Yasmine Bennouna, Maria Tsivlidou, Pawel Wolff, Bastien Sauvage, Brice Barret, Eric Le Flochmoën, Romain Blot, Damien Boulanger, Jean-Marc Cousin, Philippe Nédélec, Andreas Petzold, and Valérie Thouret
Atmos. Chem. Phys., 21, 16237–16256, https://doi.org/10.5194/acp-21-16237-2021, https://doi.org/10.5194/acp-21-16237-2021, 2021
Short summary
Short summary
We examined 27 years of IAGOS (In-service Aircraft for a Global Observing System) profiles at Frankfurt to see if there were unusual features during the spring of 2020 related to COVID-19 lockdowns in Europe. Increased ozone near the surface was partly linked to the reduction in emissions. Carbon monoxide decreased near the surface, but the impact of the lockdowns was offset by polluted air masses from elsewhere. There were small reductions in ozone and carbon monoxide in the free troposphere.
Gaëlle Dufour, Didier Hauglustaine, Yunjiang Zhang, Maxim Eremenko, Yann Cohen, Audrey Gaudel, Guillaume Siour, Mathieu Lachatre, Axel Bense, Bertrand Bessagnet, Juan Cuesta, Jerry Ziemke, Valérie Thouret, and Bo Zheng
Atmos. Chem. Phys., 21, 16001–16025, https://doi.org/10.5194/acp-21-16001-2021, https://doi.org/10.5194/acp-21-16001-2021, 2021
Short summary
Short summary
The IASI observations and the LMDZ-OR-INCA model simulations show negative ozone trends in the Central East China region in the lower free (3–6 km column) and the upper free (6–9 km column) troposphere. Sensitivity studies from the model show that the Chinese anthropogenic emissions contribute to more than 50 % in the trend. The reduction in NOx emissions that has occurred since 2013 in China seems to lead to a decrease in ozone in the free troposphere, contrary to the increase at the surface.
Victor Lannuque, Bastien Sauvage, Brice Barret, Hannah Clark, Gilles Athier, Damien Boulanger, Jean-Pierre Cammas, Jean-Marc Cousin, Alain Fontaine, Eric Le Flochmoën, Philippe Nédélec, Hervé Petetin, Isabelle Pfaffenzeller, Susanne Rohs, Herman G. J. Smit, Pawel Wolff, and Valérie Thouret
Atmos. Chem. Phys., 21, 14535–14555, https://doi.org/10.5194/acp-21-14535-2021, https://doi.org/10.5194/acp-21-14535-2021, 2021
Short summary
Short summary
The African intertropical troposphere is one of the world areas where the increase in ozone mixing ratio has been most pronounced since 1980 and where high carbon monoxide mixing ratios are found in altitude. In this article, IAGOS aircraft measurements, IASI satellite instrument observations, and SOFT-IO model products are used to explore the seasonal distribution variations and the origin of ozone and carbon monoxide over the African upper troposphere.
Nora Mettig, Mark Weber, Alexei Rozanov, Carlo Arosio, John P. Burrows, Pepijn Veefkind, Anne M. Thompson, Richard Querel, Thierry Leblanc, Sophie Godin-Beekmann, Rigel Kivi, and Matthew B. Tully
Atmos. Meas. Tech., 14, 6057–6082, https://doi.org/10.5194/amt-14-6057-2021, https://doi.org/10.5194/amt-14-6057-2021, 2021
Short summary
Short summary
TROPOMI is a nadir-viewing satellite that has observed global atmospheric trace gases at unprecedented spatial resolution since 2017. The retrieval of ozone profiles with high accuracy has been demonstrated using the TOPAS (Tikhonov regularised Ozone Profile retrievAl with SCIATRAN) algorithm and applying appropriate spectral corrections to TROPOMI UV data. Ozone profiles from TROPOMI were compared to ozonesonde and lidar profiles, showing an agreement to within 5 % in the stratosphere.
Roeland Van Malderen, Dirk De Muer, Hugo De Backer, Deniz Poyraz, Willem W. Verstraeten, Veerle De Bock, Andy W. Delcloo, Alexander Mangold, Quentin Laffineur, Marc Allaart, Frans Fierens, and Valérie Thouret
Atmos. Chem. Phys., 21, 12385–12411, https://doi.org/10.5194/acp-21-12385-2021, https://doi.org/10.5194/acp-21-12385-2021, 2021
Short summary
Short summary
The main aim of initiating measurements of the vertical distribution of the ozone concentration by means of ozonesondes attached to weather balloons at Uccle in 1969 was to improve weather forecasts. Since then, this measurement technique has barely changed, but the dense, long-term, and homogeneous Uccle dataset currently remains crucial for studying the temporal evolution of ozone from the surface to the stratosphere and is also the backbone of the validation of satellite ozone retrievals.
Jianfeng Li, Yuhang Wang, Ruixiong Zhang, Charles Smeltzer, Andrew Weinheimer, Jay Herman, K. Folkert Boersma, Edward A. Celarier, Russell W. Long, James J. Szykman, Ruben Delgado, Anne M. Thompson, Travis N. Knepp, Lok N. Lamsal, Scott J. Janz, Matthew G. Kowalewski, Xiong Liu, and Caroline R. Nowlan
Atmos. Chem. Phys., 21, 11133–11160, https://doi.org/10.5194/acp-21-11133-2021, https://doi.org/10.5194/acp-21-11133-2021, 2021
Short summary
Short summary
Comprehensive evaluations of simulated diurnal cycles of NO2 and NOy concentrations, vertical profiles, and tropospheric vertical column densities at two different resolutions with various measurements during the DISCOVER-AQ 2011 campaign show potential distribution biases of NOx emissions in the National Emissions Inventory 2011 at both 36 and 4 km resolutions, providing another possible explanation for the overestimation of model results.
Romain Blot, Philippe Nedelec, Damien Boulanger, Pawel Wolff, Bastien Sauvage, Jean-Marc Cousin, Gilles Athier, Andreas Zahn, Florian Obersteiner, Dieter Scharffe, Hervé Petetin, Yasmine Bennouna, Hannah Clark, and Valérie Thouret
Atmos. Meas. Tech., 14, 3935–3951, https://doi.org/10.5194/amt-14-3935-2021, https://doi.org/10.5194/amt-14-3935-2021, 2021
Short summary
Short summary
A lack of information about temporal changes in measurement uncertainties is an area of concern for long-term trend studies of the key compounds which have a direct or indirect impact on climate change. The IAGOS program has measured O3 and CO within the troposphere and lower stratosphere for more than 25 years. In this study, we demonstrated that the IAGOS database can be treated as one continuous program and is therefore appropriate for studies of long-term trends.
Yann Cohen, Virginie Marécal, Béatrice Josse, and Valérie Thouret
Geosci. Model Dev., 14, 2659–2689, https://doi.org/10.5194/gmd-14-2659-2021, https://doi.org/10.5194/gmd-14-2659-2021, 2021
Short summary
Short summary
Assessing long-term chemistry–climate simulations with in situ and frequent observations near the tropopause is possible with the IAGOS commercial aircraft data set. This study presents a method that distributes the IAGOS data (ozone and CO) on a monthly model grid, limiting the impact of resolution for the evaluation of the modelled chemical fields. We applied it to the CCMI REF-C1SD simulation from the MOCAGE CTM and notably highlighted well-reproduced O3 behaviour in the lower stratosphere.
Holger Vömel, Mack Goodstein, Laura Tudor, Jacquelyn Witte, Željka Fuchs-Stone, Stipo Sentić, David Raymond, Jose Martinez-Claros, Ana Juračić, Vijit Maithel, and Justin W. Whitaker
Earth Syst. Sci. Data, 13, 1107–1117, https://doi.org/10.5194/essd-13-1107-2021, https://doi.org/10.5194/essd-13-1107-2021, 2021
Short summary
Short summary
We provide an extensive data set of in situ vertical profile observations for pressure, temperature, humidity, and winds from 648 NCAR NRD41 dropsondes during the Organization of Tropical East Pacific Convection (OTREC) field campaign. The measurements were taken during 22 flights of the NSF/NCAR G-V research aircraft in August and September 2019 over the eastern Pacific Ocean and the Caribbean Sea. The data allow a detailed study of atmospheric dynamics and convection over the tropical ocean.
Holger Vömel, Herman G. J. Smit, David Tarasick, Bryan Johnson, Samuel J. Oltmans, Henry Selkirk, Anne M. Thompson, Ryan M. Stauffer, Jacquelyn C. Witte, Jonathan Davies, Roeland van Malderen, Gary A. Morris, Tatsumi Nakano, and Rene Stübi
Atmos. Meas. Tech., 13, 5667–5680, https://doi.org/10.5194/amt-13-5667-2020, https://doi.org/10.5194/amt-13-5667-2020, 2020
Short summary
Short summary
The time response of electrochemical concentration cell (ECC) ozonesondes points to at least two distinct reaction pathways with time constants of approximately 20 s and 25 min. Properly considering these time constants eliminates the need for a poorly defined "background" and allows reducing ad hoc corrections based on laboratory tests. This reduces the uncertainty of ECC ozonesonde measurements throughout the profile and especially in regions of low ozone and strong gradients of ozone.
Minqiang Zhou, Pucai Wang, Bavo Langerock, Corinne Vigouroux, Christian Hermans, Nicolas Kumps, Ting Wang, Yang Yang, Denghui Ji, Liang Ran, Jinqiang Zhang, Yuejian Xuan, Hongbin Chen, Françoise Posny, Valentin Duflot, Jean-Marc Metzger, and Martine De Mazière
Atmos. Meas. Tech., 13, 5379–5394, https://doi.org/10.5194/amt-13-5379-2020, https://doi.org/10.5194/amt-13-5379-2020, 2020
Short summary
Short summary
We study O3 retrievals in the 3040 cm-1 spectral range from FTIR measurements at Xianghe China (39.75° N, 116.96° E; 50 m a.s.l.) between June 2018 and December 2019. It was found that the FTIR O3 (3040 cm-1) retrievals capture the seasonal and synoptic variations of O3 very well. The systematic and random uncertainties of FTIR O3 (3040 cm-1) total column are about 13.6 % and 1.4 %, respectively. The DOFS is 2.4±0.3 (1σ), with two individual pieces of information in surface–20 km and 20–40 km.
Ilann Bourgeois, Jeff Peischl, Chelsea R. Thompson, Kenneth C. Aikin, Teresa Campos, Hannah Clark, Róisín Commane, Bruce Daube, Glenn W. Diskin, James W. Elkins, Ru-Shan Gao, Audrey Gaudel, Eric J. Hintsa, Bryan J. Johnson, Rigel Kivi, Kathryn McKain, Fred L. Moore, David D. Parrish, Richard Querel, Eric Ray, Ricardo Sánchez, Colm Sweeney, David W. Tarasick, Anne M. Thompson, Valérie Thouret, Jacquelyn C. Witte, Steve C. Wofsy, and Thomas B. Ryerson
Atmos. Chem. Phys., 20, 10611–10635, https://doi.org/10.5194/acp-20-10611-2020, https://doi.org/10.5194/acp-20-10611-2020, 2020
Stephanie Evan, Jerome Brioude, Karen Rosenlof, Sean M. Davis, Holger Vömel, Damien Héron, Françoise Posny, Jean-Marc Metzger, Valentin Duflot, Guillaume Payen, Hélène Vérèmes, Philippe Keckhut, and Jean-Pierre Cammas
Atmos. Chem. Phys., 20, 10565–10586, https://doi.org/10.5194/acp-20-10565-2020, https://doi.org/10.5194/acp-20-10565-2020, 2020
Short summary
Short summary
The role of deep convection in the southwest Indian Ocean (the 3rd most active tropical cyclone basin) on the composition of the tropical tropopause layer (TTL) and the climate system is less understood due to scarce observations. Balloon-borne lidar and satellite measurements in the southwest Indian Ocean were used to study tropical cyclones' influence on TTL composition. This study compares the impact of a tropical storm and cyclone on the humidification of the TTL over the SW Indian Ocean.
Kai-Lan Chang, Owen R. Cooper, Audrey Gaudel, Irina Petropavlovskikh, and Valérie Thouret
Atmos. Chem. Phys., 20, 9915–9938, https://doi.org/10.5194/acp-20-9915-2020, https://doi.org/10.5194/acp-20-9915-2020, 2020
Short summary
Short summary
We provide a statistical framework for detecting trends of multiple autocorrelated time series from sparsely sampled profile data. The result is a better and more consistent quantification of trend estimates of vertical profile data. The focus was placed on the long-term ozone time series from commercial aircraft and balloon-borne ozonesonde measurements. This framework can be applied to other trace gases in the atmosphere.
Martin Cussac, Virginie Marécal, Valérie Thouret, Béatrice Josse, and Bastien Sauvage
Atmos. Chem. Phys., 20, 9393–9417, https://doi.org/10.5194/acp-20-9393-2020, https://doi.org/10.5194/acp-20-9393-2020, 2020
Short summary
Short summary
Biomass burning emissions are a major source of carbon monoxide in the atmosphere. Here, the vertical transport that these emissions can undergo until the upper troposphere is investigated, as well as their contribution to carbon monoxide concentrations. It was found that boreal forest emissions were specific to the occurrence of pyroconvection directly above the fires, whereas biomass burning emissions from other regions of the globe relied more on the occurrence of deep convection.
Damien Héron, Stéphanie Evan, Jérôme Brioude, Karen Rosenlof, Françoise Posny, Jean-Marc Metzger, and Jean-Pierre Cammas
Atmos. Chem. Phys., 20, 8611–8626, https://doi.org/10.5194/acp-20-8611-2020, https://doi.org/10.5194/acp-20-8611-2020, 2020
Short summary
Short summary
Using a statistical method, summer variations (between 2013 and 2016) of ozone and water vapor are characterized in the upper troposphere above Réunion island (21° S, 55° E). It suggests a convective influence between 9 and 13 km. As deep convection is rarely observed near Réunion island, this study provides new insights on the long-range impact of deep convective outflow from the Intertropical Convergence Zone (ITCZ) on the upper troposphere over a subtropical site.
Nikolay V. Balashov, Kenneth J. Davis, Natasha L. Miles, Thomas Lauvaux, Scott J. Richardson, Zachary R. Barkley, and Timothy A. Bonin
Atmos. Chem. Phys., 20, 4545–4559, https://doi.org/10.5194/acp-20-4545-2020, https://doi.org/10.5194/acp-20-4545-2020, 2020
Short summary
Short summary
An accurate independent verification methodology to estimate methane (a powerful greenhouse gas) emissions is essential for the effective implementation of policies that aim to reduce the impacts of climate change. In this paper, four uncertainties that complicate the independent estimation of urban methane emissions are identified: the definition of urban domain, background heterogeneity, emissions temporal variability, and missing sources. Ways to improve emission estimates are suggested.
John T. Sullivan, Thomas J. McGee, Ryan M. Stauffer, Anne M. Thompson, Andrew Weinheimer, Christoph Knote, Scott Janz, Armin Wisthaler, Russell Long, James Szykman, Jinsoo Park, Youngjae Lee, Saewung Kim, Daun Jeong, Dianne Sanchez, Laurence Twigg, Grant Sumnicht, Travis Knepp, and Jason R. Schroeder
Atmos. Chem. Phys., 19, 5051–5067, https://doi.org/10.5194/acp-19-5051-2019, https://doi.org/10.5194/acp-19-5051-2019, 2019
Short summary
Short summary
During the May–June 2016 International Cooperative Air Quality Field Study in Korea (KORUS-AQ), pollution reached the remote Taehwa Research Forest (TRF) site. Two case studies are examined and observations clearly identify TRF and the surrounding rural areas as long-term receptor sites for severe urban pollution events. In summary, domestic emissions may be causing more pollution than by transboundary pathways, which have been historically believed to be the major source of air pollution.
Jerry R. Ziemke, Luke D. Oman, Sarah A. Strode, Anne R. Douglass, Mark A. Olsen, Richard D. McPeters, Pawan K. Bhartia, Lucien Froidevaux, Gordon J. Labow, Jacquie C. Witte, Anne M. Thompson, David P. Haffner, Natalya A. Kramarova, Stacey M. Frith, Liang-Kang Huang, Glen R. Jaross, Colin J. Seftor, Mathew T. Deland, and Steven L. Taylor
Atmos. Chem. Phys., 19, 3257–3269, https://doi.org/10.5194/acp-19-3257-2019, https://doi.org/10.5194/acp-19-3257-2019, 2019
Short summary
Short summary
Both a 38-year merged satellite record of tropospheric ozone from TOMS/OMI/MLS/OMPS and a MERRA-2 GMI model simulation show large increases of 6–7 Dobson units from the Near East to India–East Asia and eastward over the Pacific. These increases in tropospheric ozone are attributed to increases in pollution over the region over the last several decades. Secondary 38-year increases of 4–5 Dobson units with both GMI model and satellite measurements occur over central African–tropical Atlantic.
Hervé Petetin, Bastien Sauvage, Mark Parrington, Hannah Clark, Alain Fontaine, Gilles Athier, Romain Blot, Damien Boulanger, Jean-Marc Cousin, Philippe Nédélec, and Valérie Thouret
Atmos. Chem. Phys., 18, 17277–17306, https://doi.org/10.5194/acp-18-17277-2018, https://doi.org/10.5194/acp-18-17277-2018, 2018
Short summary
Short summary
This study derives a climatology of the impact of biomass burning versus anthropogenic emissions on the strongest CO plumes observed in the troposphere based on a dataset of about 30 000 in situ vertical profiles, combined with Lagrangian simulations coupled to CO emission. Results demonstrate the large contribution of biomass burning to the strongest CO plumes encountered in the troposphere in many locations of the world.
Tracey Leah Laban, Pieter Gideon van Zyl, Johan Paul Beukes, Ville Vakkari, Kerneels Jaars, Nadine Borduas-Dedekind, Miroslav Josipovic, Anne Mee Thompson, Markku Kulmala, and Lauri Laakso
Atmos. Chem. Phys., 18, 15491–15514, https://doi.org/10.5194/acp-18-15491-2018, https://doi.org/10.5194/acp-18-15491-2018, 2018
Short summary
Short summary
Surface O3 was measured at four sites in the north-eastern interior of South Africa, which revealed that O3 is a regional problem in continental South Africa, with elevated O3 levels found at rural background and industrial sites. Increased O3 concentrations were associated with high CO levels predominantly related to regional biomass burning, while the O3 production regime was established to be predominantly VOC limited. Increased O3 is associated with strong seasonality of precursor sources.
Dejian Fu, Susan S. Kulawik, Kazuyuki Miyazaki, Kevin W. Bowman, John R. Worden, Annmarie Eldering, Nathaniel J. Livesey, Joao Teixeira, Fredrick W. Irion, Robert L. Herman, Gregory B. Osterman, Xiong Liu, Pieternel F. Levelt, Anne M. Thompson, and Ming Luo
Atmos. Meas. Tech., 11, 5587–5605, https://doi.org/10.5194/amt-11-5587-2018, https://doi.org/10.5194/amt-11-5587-2018, 2018
Wenfu Tang, Avelino F. Arellano, Joshua P. DiGangi, Yonghoon Choi, Glenn S. Diskin, Anna Agustí-Panareda, Mark Parrington, Sebastien Massart, Benjamin Gaubert, Youngjae Lee, Danbi Kim, Jinsang Jung, Jinkyu Hong, Je-Woo Hong, Yugo Kanaya, Mindo Lee, Ryan M. Stauffer, Anne M. Thompson, James H. Flynn, and Jung-Hun Woo
Atmos. Chem. Phys., 18, 11007–11030, https://doi.org/10.5194/acp-18-11007-2018, https://doi.org/10.5194/acp-18-11007-2018, 2018
Hervé Petetin, Bastien Sauvage, Herman G. J. Smit, François Gheusi, Fabienne Lohou, Romain Blot, Hannah Clark, Gilles Athier, Damien Boulanger, Jean-Marc Cousin, Philippe Nedelec, Patrick Neis, Susanne Rohs, and Valérie Thouret
Atmos. Chem. Phys., 18, 9561–9581, https://doi.org/10.5194/acp-18-9561-2018, https://doi.org/10.5194/acp-18-9561-2018, 2018
Short summary
Short summary
Based on the numerous profiles available since 1994, this paper investigates the vertical stratification of ozone, carbon monoxide and relative humidity in the lower part of the troposphere (planetary boundary layer, lower free troposphere). Such a characterization of the vertical distribution of pollution is notably important for better understanding vertical exchanges and evaluating models on the vertical dimension.
Fabio Boschetti, Valerie Thouret, Greet Janssens Maenhout, Kai Uwe Totsche, Julia Marshall, and Christoph Gerbig
Atmos. Chem. Phys., 18, 9225–9241, https://doi.org/10.5194/acp-18-9225-2018, https://doi.org/10.5194/acp-18-9225-2018, 2018
Short summary
Short summary
Retrieving surface–atmosphere fluxes from the combination of atmospheric observations with atmospheric transport models can benefit from combining multiple species in a single inversion. The underlying effect is that species such as CO2 and CO have partially overlapping emission patterns for given sectors and fuel types and so share part of the uncertainties, both related to the a priori knowledge of emissions, and to model–data mismatch error. We show this for airborne profile data from IAGOS.
Elpida Leventidou, Mark Weber, Kai-Uwe Eichmann, John P. Burrows, Klaus-Peter Heue, Anne M. Thompson, and Bryan J. Johnson
Atmos. Chem. Phys., 18, 9189–9205, https://doi.org/10.5194/acp-18-9189-2018, https://doi.org/10.5194/acp-18-9189-2018, 2018
Short summary
Short summary
Three individual tropical tropospheric ozone (TTCO) datasets (1996–2015) retrieved with the convective-cloud differential method (Leventidou et al., 2016) have been harmonised in order to study the global and regional TTCO trends. The trends range between −4 to 4 DU per decade testing six different merging scenarios. No trend has been found for the global tropics using the preferred scenario. It is concluded that harmonisation is one of the major sources of uncertainty in the trend estimates.
Chance W. Sterling, Bryan J. Johnson, Samuel J. Oltmans, Herman G. J. Smit, Allen F. Jordan, Patrick D. Cullis, Emrys G. Hall, Anne M. Thompson, and Jacquelyn C. Witte
Atmos. Meas. Tech., 11, 3661–3687, https://doi.org/10.5194/amt-11-3661-2018, https://doi.org/10.5194/amt-11-3661-2018, 2018
Short summary
Short summary
The electrochemical concentration cell ozonesonde is a balloon-borne instrument that measures ozone to an altitude of ~30 km. This work summarizes the National Oceanic and Atmospheric Administration's 50+ year, eight-site ozonesonde network history, the processing techniques utilized to account for instrumental changes, and the uncertainty of the measurement. The ozonesonde measurements were compared to satellite measurements and agreed well. This important data set is more useful and robust.
Yann Cohen, Hervé Petetin, Valérie Thouret, Virginie Marécal, Béatrice Josse, Hannah Clark, Bastien Sauvage, Alain Fontaine, Gilles Athier, Romain Blot, Damien Boulanger, Jean-Marc Cousin, and Philippe Nédélec
Atmos. Chem. Phys., 18, 5415–5453, https://doi.org/10.5194/acp-18-5415-2018, https://doi.org/10.5194/acp-18-5415-2018, 2018
Short summary
Short summary
Measurements of ozone and carbon monoxide were performed during 1994–2013 around the tropopause on board commercial aircraft. Seasonal cycles and trends were calculated above eight well-sampled regions in Northern Hemisphere midlatitudes. CO shows decreasing concentrations over the last 10 years, thus reflecting the impact of the legislation on anthropogenic emissions. Ozone amounts increased over the 20 years in the upper troposphere during different seasons, depending on the longitudes.
Martine De Mazière, Anne M. Thompson, Michael J. Kurylo, Jeannette D. Wild, Germar Bernhard, Thomas Blumenstock, Geir O. Braathen, James W. Hannigan, Jean-Christopher Lambert, Thierry Leblanc, Thomas J. McGee, Gerald Nedoluha, Irina Petropavlovskikh, Gunther Seckmeyer, Paul C. Simon, Wolfgang Steinbrecht, and Susan E. Strahan
Atmos. Chem. Phys., 18, 4935–4964, https://doi.org/10.5194/acp-18-4935-2018, https://doi.org/10.5194/acp-18-4935-2018, 2018
Short summary
Short summary
This paper serves as an introduction to the special issue "Twenty-five years of operations of the Network for the Detection of Atmospheric Composition Change (NDACC)". It describes the origins of the network, its actual status, and some perspectives for its future evolution in the context of atmospheric sciences.
Nelson Bègue, Damien Vignelles, Gwenaël Berthet, Thierry Portafaix, Guillaume Payen, Fabrice Jégou, Hassan Benchérif, Julien Jumelet, Jean-Paul Vernier, Thibaut Lurton, Jean-Baptiste Renard, Lieven Clarisse, Vincent Duverger, Françoise Posny, Jean-Marc Metzger, and Sophie Godin-Beekmann
Atmos. Chem. Phys., 17, 15019–15036, https://doi.org/10.5194/acp-17-15019-2017, https://doi.org/10.5194/acp-17-15019-2017, 2017
Short summary
Short summary
The space–time evolutions of the Calbuco plume are investigated by combining satellite, in situ aerosol counting and lidar observations, and a numerical model. All the data at Reunion Island reveal a twofold increase in the amount of aerosol with respect to the values observed before the eruption. The dynamic context has favored the spread of the plume exclusively in the Southern Hemisphere. This study highlights the role played by dynamical barriers in the transport of atmospheric species.
Florian Berkes, Patrick Neis, Martin G. Schultz, Ulrich Bundke, Susanne Rohs, Herman G. J. Smit, Andreas Wahner, Paul Konopka, Damien Boulanger, Philippe Nédélec, Valerie Thouret, and Andreas Petzold
Atmos. Chem. Phys., 17, 12495–12508, https://doi.org/10.5194/acp-17-12495-2017, https://doi.org/10.5194/acp-17-12495-2017, 2017
Short summary
Short summary
This study highlights the importance of independent global measurements with high and long-term accuracy to quantify long-term changes, especially in the UTLS region, and to help identify inconsistencies between different data sets of observations and models. Here we investigated temperature trends over different regions within a climate-sensitive area of the atmosphere and demonstrated the value of the IAGOS temperature observations as an anchor point for the evaluation of reanalyses.
Valentin Duflot, Jean-Luc Baray, Guillaume Payen, Nicolas Marquestaut, Francoise Posny, Jean-Marc Metzger, Bavo Langerock, Corinne Vigouroux, Juliette Hadji-Lazaro, Thierry Portafaix, Martine De Mazière, Pierre-Francois Coheur, Cathy Clerbaux, and Jean-Pierre Cammas
Atmos. Meas. Tech., 10, 3359–3373, https://doi.org/10.5194/amt-10-3359-2017, https://doi.org/10.5194/amt-10-3359-2017, 2017
Katherine R. Travis, Daniel J. Jacob, Christoph A. Keller, Shi Kuang, Jintai Lin, Michael J. Newchurch, and Anne M. Thompson
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2017-596, https://doi.org/10.5194/acp-2017-596, 2017
Preprint retracted
Short summary
Short summary
Models severely overestimate surface ozone in the Southeast US during summertime which has implications for the design of air quality regulations. We use a model (GEOS-Chem) to interpret ozone observations from a suite of observations taken during August–September 2013. The model is unbiased relative to observations below 1 km but is biased high at the surface. We attribute this bias to model representation error, an underestimate in low-cloud, and insufficient treatment of vertical mixing.
Guanyu Huang, Xiong Liu, Kelly Chance, Kai Yang, Pawan K. Bhartia, Zhaonan Cai, Marc Allaart, Gérard Ancellet, Bertrand Calpini, Gerrie J. R. Coetzee, Emilio Cuevas-Agulló, Manuel Cupeiro, Hugo De Backer, Manvendra K. Dubey, Henry E. Fuelberg, Masatomo Fujiwara, Sophie Godin-Beekmann, Tristan J. Hall, Bryan Johnson, Everette Joseph, Rigel Kivi, Bogumil Kois, Ninong Komala, Gert König-Langlo, Giovanni Laneve, Thierry Leblanc, Marion Marchand, Kenneth R. Minschwaner, Gary Morris, Michael J. Newchurch, Shin-Ya Ogino, Nozomu Ohkawara, Ankie J. M. Piters, Françoise Posny, Richard Querel, Rinus Scheele, Frank J. Schmidlin, Russell C. Schnell, Otto Schrems, Henry Selkirk, Masato Shiotani, Pavla Skrivánková, René Stübi, Ghassan Taha, David W. Tarasick, Anne M. Thompson, Valérie Thouret, Matthew B. Tully, Roeland Van Malderen, Holger Vömel, Peter von der Gathen, Jacquelyn C. Witte, and Margarita Yela
Atmos. Meas. Tech., 10, 2455–2475, https://doi.org/10.5194/amt-10-2455-2017, https://doi.org/10.5194/amt-10-2455-2017, 2017
Short summary
Short summary
It is essential to understand the data quality of +10-year OMI ozone product and impacts of the “row anomaly” (RA). We validate the OMI Ozone Profile (PROFOZ) product from Oct 2004 to Dec 2014 against ozonesonde observations globally. Generally, OMI has good agreement with ozonesondes. The spatiotemporal variation of retrieval performance suggests the need to improve OMI’s radiometric calibration especially during the post-RA period to maintain the long-term stability.
Hélène Vérèmes, Guillaume Payen, Philippe Keckhut, Valentin Duflot, Jean-Luc Baray, Jean-Pierre Cammas, Jimmy Leclair De Bellevue, Stéphanie Evan, Françoise Posny, Franck Gabarrot, Jean-Marc Metzger, Nicolas Marquestaut, Susanne Meier, Holger Vömel, and Ruud Dirksen
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2017-32, https://doi.org/10.5194/amt-2017-32, 2017
Preprint withdrawn
Hervé Petetin, Valérie Thouret, Alain Fontaine, Bastien Sauvage, Giles Athier, Romain Blot, Damien Boulanger, Jean-Marc Cousin, and Philippe Nédélec
Atmos. Chem. Phys., 16, 15147–15163, https://doi.org/10.5194/acp-16-15147-2016, https://doi.org/10.5194/acp-16-15147-2016, 2016
Short summary
Short summary
Ozone (O3) and carbon monoxide (CO) are two compounds of major importance in the atmosphere. In this paper we investigated their variability and trends at Frankfurt based on the MOZAIC–IAGOS dataset, a unique dataset of about 21 300 vertical profiles recorded by commercial aircraft. The CO concentrations have been decreasing since 2002, while no strong tendency is observed for O3 since 1994. However, the O3 seasonal variations are changing, with the spring maximum occurring earlier and earlier.
Susana Fernandez, Rolf Rüfenacht, Niklaus Kämpfer, Thierry Portafaix, Françoise Posny, and Guillaume Payen
Atmos. Chem. Phys., 16, 7531–7543, https://doi.org/10.5194/acp-16-7531-2016, https://doi.org/10.5194/acp-16-7531-2016, 2016
Short summary
Short summary
We present a new ground based microwave radiometer for campaigns, GROMOS-C. It measures the vertical distribution of ozone in the middle atmosphere by observing spectra at 110.836 GHz. The paper presents a validation campaign that took place on La Réunion Island. The ozone retrieved profiles are validated against ozone profiles from the Microwave Limb Sounder, the ozone lidar located in the observatory, ozone profiles from weekly radiosondes and with ECMWF model data.
J. Aschmann, J. P. Burrows, C. Gebhardt, A. Rozanov, R. Hommel, M. Weber, and A. M. Thompson
Atmos. Chem. Phys., 14, 12803–12814, https://doi.org/10.5194/acp-14-12803-2014, https://doi.org/10.5194/acp-14-12803-2014, 2014
Short summary
Short summary
This study compares observations and simulation results of ozone in the lower tropical stratosphere. It shows that ozone in this region decreased from 1985 up to about 2002, which is consistent with an increase in tropical upwelling predicted by climate models. However, the decrease effectively stops after 2002, indicating that significant changes in tropical upwelling have occurred. The most important factor appears to be that the vertical ascent in the tropics is no longer accelerating.
J. Staufer, J. Staehelin, R. Stübi, T. Peter, F. Tummon, and V. Thouret
Atmos. Meas. Tech., 7, 241–266, https://doi.org/10.5194/amt-7-241-2014, https://doi.org/10.5194/amt-7-241-2014, 2014
C. Gebhardt, A. Rozanov, R. Hommel, M. Weber, H. Bovensmann, J. P. Burrows, D. Degenstein, L. Froidevaux, and A. M. Thompson
Atmos. Chem. Phys., 14, 831–846, https://doi.org/10.5194/acp-14-831-2014, https://doi.org/10.5194/acp-14-831-2014, 2014
R. M. Stauffer, G. A. Morris, A. M. Thompson, E. Joseph, G. J. R. Coetzee, and N. R. Nalli
Atmos. Meas. Tech., 7, 65–79, https://doi.org/10.5194/amt-7-65-2014, https://doi.org/10.5194/amt-7-65-2014, 2014
R. M. Zbinden, V. Thouret, P. Ricaud, F. Carminati, J.-P. Cammas, and P. Nédélec
Atmos. Chem. Phys., 13, 12363–12388, https://doi.org/10.5194/acp-13-12363-2013, https://doi.org/10.5194/acp-13-12363-2013, 2013
J. Staufer, J. Staehelin, R. Stübi, T. Peter, F. Tummon, and V. Thouret
Atmos. Meas. Tech., 6, 3393–3406, https://doi.org/10.5194/amt-6-3393-2013, https://doi.org/10.5194/amt-6-3393-2013, 2013
J.-L. Baray, Y. Courcoux, P. Keckhut, T. Portafaix, P. Tulet, J.-P. Cammas, A. Hauchecorne, S. Godin Beekmann, M. De Mazière, C. Hermans, F. Desmet, K. Sellegri, A. Colomb, M. Ramonet, J. Sciare, C. Vuillemin, C. Hoareau, D. Dionisi, V. Duflot, H. Vérèmes, J. Porteneuve, F. Gabarrot, T. Gaudo, J.-M. Metzger, G. Payen, J. Leclair de Bellevue, C. Barthe, F. Posny, P. Ricaud, A. Abchiche, and R. Delmas
Atmos. Meas. Tech., 6, 2865–2877, https://doi.org/10.5194/amt-6-2865-2013, https://doi.org/10.5194/amt-6-2865-2013, 2013
P. D. Kalabokas, J.-P. Cammas, V. Thouret, A. Volz-Thomas, D. Boulanger, and C. C. Repapis
Atmos. Chem. Phys., 13, 10339–10352, https://doi.org/10.5194/acp-13-10339-2013, https://doi.org/10.5194/acp-13-10339-2013, 2013
A. Inness, F. Baier, A. Benedetti, I. Bouarar, S. Chabrillat, H. Clark, C. Clerbaux, P. Coheur, R. J. Engelen, Q. Errera, J. Flemming, M. George, C. Granier, J. Hadji-Lazaro, V. Huijnen, D. Hurtmans, L. Jones, J. W. Kaiser, J. Kapsomenakis, K. Lefever, J. Leitão, M. Razinger, A. Richter, M. G. Schultz, A. J. Simmons, M. Suttie, O. Stein, J.-N. Thépaut, V. Thouret, M. Vrekoussis, C. Zerefos, and the MACC team
Atmos. Chem. Phys., 13, 4073–4109, https://doi.org/10.5194/acp-13-4073-2013, https://doi.org/10.5194/acp-13-4073-2013, 2013
Related subject area
Subject: Gases | Research Activity: Field Measurements | Altitude Range: Troposphere | Science Focus: Chemistry (chemical composition and reactions)
Formation drivers and photochemical effects of ClNO2 in a coastal city of Southeast China
Significant influence of oxygenated volatile organic compounds on atmospheric chemistry: a case study in a typical industrial city in China
Global ground-based tropospheric ozone measurements: reference data and individual site trends (2000–2022) from the TOAR-II/HEGIFTOM project
Understanding summertime H2O2 chemistry in the North China Plain through observations and modeling studies
Volatile organic compound sources and impacts in an urban Mediterranean area (Marseille, France)
Short-lived organic nitrates in a suburban temperate forest: an indication of efficient assimilation of reactive nitrogen by the biosphere?
Spatiotemporal variations in atmospheric CH4 concentrations and enhancements in northern China based on a comprehensive dataset: ground-based observations, TROPOMI data, inventory data, and inversions
Marine emissions and trade winds control the atmospheric nitrous oxide in the Galapagos Islands
Measurement report: A complex street-level air quality observation campaign in a heavy-traffic area utilizing the multivariate adaptive regression splines method for field calibration of low-cost sensors
The impact of organic nitrates on summer ozone formation in Shanghai, China
Differences in the key volatile organic compound species between their emitted and ambient concentrations in ozone formation
Tracing Ammonia Emission Sources in California's Salton Sea Region: Insights from Airborne Longwave-Infrared Hyperspectral Imaging and Ground Monitoring
Mechanistic insights into chloroacetic acid production from atmospheric multiphase volatile organic compound–chlorine chemistry
Accurate elucidation of oxidation under heavy ozone pollution: a full suite of radical measurements in the chemically complex atmosphere
Carbonyl compounds from typical combustion sources: emission characteristics, influencing factors, and their contribution to ozone formation
Emissions of intermediate-volatility and semi-volatile organic compounds (I/SVOCs) from different cumulative-mileage diesel vehicles at various ambient temperatures
Characterization of nitrous acid and its potential effects on secondary pollution in the warm season in Beijing urban areas
Vertical changes in volatile organic compounds (VOCs) and impacts on photochemical ozone formation
Airborne quantification of Angolan offshore oil and gas methane emissions
Diurnal, seasonal, and interannual variations in δ(18O) of atmospheric O2 and its application to evaluate natural and anthropogenic changes in oxygen, carbon, and water cycles
Cloud processing of dimethyl sulfide (DMS) oxidation products limits sulfur dioxide (SO2) and carbonyl sulfide (OCS) production in the eastern North Atlantic marine boundary layer
Atmospheric carbonyl compounds are crucial in regional ozone heavy pollution: insights from the Chengdu Plain Urban Agglomeration, China
Evaluating urban methane emissions and their attributes in a megacity, Osaka, Japan, via mobile and eddy covariance measurements
Ozone (O3) observations in Saxony, Germany for 1997–2020: Trends, modelling and implications for O3 control
Understanding summertime peroxyacetyl nitrate (PAN) formation and its relation to aerosol pollution: insights from high-resolution measurements and modeling
Measurement report: Exploring the variations in ambient BTEX in urban Europe and their environmental health implications
Seasonal air concentration variability, gas–particle partitioning, precipitation scavenging, and air–water equilibrium of organophosphate esters in southern Canada
Tracing elevated abundance of CH2Cl2 in the subarctic upper troposphere to the Asian Summer Monsoon
Measurement report: Surface exchange fluxes of HONO during the growth process of paddy fields in the Huaihe River Basin, China
Hemispheric differences in ozone across the stratosphere-troposphere exchange region
Molecular and seasonal characteristics of organic vapors in urban Beijing: insights from Vocus-PTR measurements
BVOC and speciated monoterpene concentrations and fluxes at a Scandinavian boreal forest
The variations in volatile organic compounds based on the policy change for Omicron in the traffic hub of Zhengzhou
On the dynamics of ozone depletion events at Villum Research Station in the High Arctic
Measurement report: Long-term measurements of surface ozone and trends in semi-natural sub-Saharan African ecosystems
Characterization of biogenic volatile organic compounds and their oxidation products in a stressed spruce-dominated forest close to a biogas power plant
Reactive chlorine-, sulfur-, and nitrogen-containing volatile organic compounds impact atmospheric chemistry in the megacity of Delhi during both clean and extremely polluted seasons
Analysis of the day-to-day variability of ozone vertical profiles in the lower troposphere during the 2022 Paris ACROSS campaign
Ozone deposition measurements over wheat fields in the North China Plain: variability and related factors of deposition flux and velocity
Consistency evaluation of tropospheric ozone from ozonesonde and IAGOS (In-service Aircraft for a Global Observing System) observations: vertical distribution, ozonesonde types, and station–airport distance
CO2 and CO temporal variability over Mexico City from ground-based total column and surface measurements
Investigating carbonyl compounds above the Amazon rainforest using a proton-transfer-reaction time-of-flight mass spectrometer (PTR-ToF-MS) with NO+ chemical ionization
Measurement report: In-flight and ground-based measurements of nitrogen oxide emissions from latest-generation jet engines and 100 % sustainable aviation fuel
Observation and modelling of atmospheric OH and HO2 radicals at a subtropical rural site and implications for secondary pollutants
Measurement report: Sources, sinks, and lifetime of NOx in a suburban temperate forest at night
Measurement report: Urban ammonia and amines in Houston, Texas
Biomass-burning sources control ambient particulate matter, but traffic and industrial sources control volatile organic compound (VOC) emissions and secondary-pollutant formation during extreme pollution events in Delhi
Multi-year observations of variable incomplete combustion in the New York megacity
Observations of the vertical distributions of summertime atmospheric pollutants in Nam Co: OH production and source analysis
Measurement report: Elevated atmospheric ammonia may promote particle pH and HONO formation – insights from the COVID-19 pandemic
Gaojie Chen, Xiaolong Fan, Haichao Wang, Yee Jun Tham, Ziyi Lin, Xiaoting Ji, Lingling Xu, Baoye Hu, and Jinsheng Chen
Atmos. Chem. Phys., 25, 7815–7828, https://doi.org/10.5194/acp-25-7815-2025, https://doi.org/10.5194/acp-25-7815-2025, 2025
Short summary
Short summary
Our study revealed that the nighttime heterogeneous dinitrogen pentoxide (N2O5) uptake process was the major contributor of nitryl chloride (ClNO2) sources, while nitrate photolysis may promote the elevation of daytime ClNO2 concentrations. The rates of alkane oxidation by chlorine (Cl) radical in the early morning exceeded those by OH radical, significantly promoted the formation of ROx and ozone (O3), and further enhanced the atmospheric oxidation capacity levels.
Jingwen Dai, Kun Zhang, Yanli Feng, Xin Yi, Rui Li, Jin Xue, Qing Li, Lishu Shi, Jiaqiang Liao, Yanan Yi, Fangting Wang, Liumei Yang, Hui Chen, Ling Huang, Jiani Tan, Yangjun Wang, and Li Li
Atmos. Chem. Phys., 25, 7467–7484, https://doi.org/10.5194/acp-25-7467-2025, https://doi.org/10.5194/acp-25-7467-2025, 2025
Short summary
Short summary
Oxygenated volatile organic compounds (OVOCs) are important ozone (O3) precursors. However, most O3 formation analysis based on the box model (OBM) does not include any OVOC constraint. To access the interference of OVOCs with O3 simulation, this study presents results from a field campaign and OBM analysis. Our results indicate that no OVOC constraint in the OBM can lead to overestimation of OVOCs, free radicals, and O3.
Roeland Van Malderen, Anne M. Thompson, Debra E. Kollonige, Ryan M. Stauffer, Herman G. J. Smit, Eliane Maillard Barras, Corinne Vigouroux, Irina Petropavlovskikh, Thierry Leblanc, Valérie Thouret, Pawel Wolff, Peter Effertz, David W. Tarasick, Deniz Poyraz, Gérard Ancellet, Marie-Renée De Backer, Stéphanie Evan, Victoria Flood, Matthias M. Frey, James W. Hannigan, José L. Hernandez, Marco Iarlori, Bryan J. Johnson, Nicholas Jones, Rigel Kivi, Emmanuel Mahieu, Glen McConville, Katrin Müller, Tomoo Nagahama, Justus Notholt, Ankie Piters, Natalia Prats, Richard Querel, Dan Smale, Wolfgang Steinbrecht, Kimberly Strong, and Ralf Sussmann
Atmos. Chem. Phys., 25, 7187–7225, https://doi.org/10.5194/acp-25-7187-2025, https://doi.org/10.5194/acp-25-7187-2025, 2025
Short summary
Short summary
Tropospheric ozone is an important greenhouse gas and is an air pollutant. The time variability of tropospheric ozone is mainly driven by anthropogenic emissions. In this paper, we study the distribution and time variability of ozone from harmonized ground-based observations from five different measurement techniques. Our findings provide clear standard references for atmospheric models and evolving tropospheric ozone satellite data for the 2000–2022 period.
Can Ye, Pengfei Liu, Chaoyang Xue, Chenglong Zhang, Zhuobiao Ma, Chengtang Liu, Junfeng Liu, Keding Lu, Yujing Mu, and Yuanhang Zhang
Atmos. Chem. Phys., 25, 6991–7005, https://doi.org/10.5194/acp-25-6991-2025, https://doi.org/10.5194/acp-25-6991-2025, 2025
Short summary
Short summary
This study investigates H2O2 chemistry in rural North China. The observed H2O2 showed distinct diurnal variations influenced by photochemical reactions. A box model revealed that H2O2 is primarily produced by HO2 recombination and removed mainly via particle uptake. Reductions in NOx, PM2.5, and alkanes raised H2O2 levels, while cutting alkenes, aromatics, CO, and HONO lowered them. A dual strategy focusing on VOC and NOx control is essential to reduce both H2O2 and ozone pollution.
Marvin Dufresne, Thérèse Salameh, Thierry Leonardis, Grégory Gille, Alexandre Armengaud, and Stéphane Sauvage
Atmos. Chem. Phys., 25, 5977–5999, https://doi.org/10.5194/acp-25-5977-2025, https://doi.org/10.5194/acp-25-5977-2025, 2025
Short summary
Short summary
This paper discusses the 18-month-long measurement of non-methane hydrocarbons (NMHCs) in Marseille, where there was no measurement since early 2000, despite the impact of NMHCs on air quality and climate. Traffic-related sources are the largest contributor to NMHC concentrations in Marseille, and shipping strongly contributes to the formation of aerosols. Finally, the Covid-19 lockdown had an impact on NMHC concentrations, reaching a 50 % decrease for traffic-related sources.
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.
Pengfei Han, Ning Zeng, Bo Yao, Wen Zhang, Weijun Quan, Pucai Wang, Ting Wang, Minqiang Zhou, Qixiang Cai, Yuzhong Zhang, Ruosi Liang, Wanqi Sun, and Shengxiang Liu
Atmos. Chem. Phys., 25, 4965–4988, https://doi.org/10.5194/acp-25-4965-2025, https://doi.org/10.5194/acp-25-4965-2025, 2025
Short summary
Short summary
Methane (CH4) is a potent greenhouse gas. Northern China contributes a large proportion of CH4 emissions, yet large observation gaps exist. Here we compiled a comprehensive dataset, which is publicly available, that includes ground-based, satellite-based, inventory, and modeling results to show the CH4 concentrations, enhancements, and spatial–temporal variations. The data can benefit the research community and policy-makers for future observations, atmospheric inversions, and policy-making.
Timur Cinay, Dickon Young, Nazaret Narváez Jimenez, Cristina Vintimilla-Palacios, Ariel Pila Alonso, Paul B. Krummel, William Vizuete, and Andrew R. Babbin
Atmos. Chem. Phys., 25, 4703–4718, https://doi.org/10.5194/acp-25-4703-2025, https://doi.org/10.5194/acp-25-4703-2025, 2025
Short summary
Short summary
We present the initial 15 months of nitrous oxide measurements from the Galapagos Emissions Monitoring Station. The observed variability in atmospheric mole fractions during this period can be linked to several factors: seasonal variations in trade wind speed and direction across the eastern Pacific, differences in the transport history of air masses sampled, and spatiotemporal heterogeneity in regional marine nitrous oxide emissions from the coastal upwelling systems of Peru and Chile.
Petra Bauerová, Josef Keder, Adriana Šindelářová, Ondřej Vlček, William Patiño, Pavel Krč, Jan Geletič, Hynek Řezníček, Martin Bureš, Kryštof Eben, Michal Belda, Jelena Radović, Vladimír Fuka, Radek Jareš, Igor Esau, and Jaroslav Resler
Atmos. Chem. Phys., 25, 4477–4504, https://doi.org/10.5194/acp-25-4477-2025, https://doi.org/10.5194/acp-25-4477-2025, 2025
Short summary
Short summary
The study explored urban air quality in Prague using low-cost sensors and highlighted the multivariate adaptive regression splines (MARS) correction method's effectiveness in enhancing accuracy. Results showed traffic's impact on nitrogen dioxide levels and atmospheric dynamics on particulate matter. The research confirmed MARS-corrected sensors as cost-effective for monitoring, despite challenges like sensor ageing and data quality control.
Chunmeng Li, Xiaorui Chen, Haichao Wang, Tianyu Zhai, Xuefei Ma, Xinping Yang, Shiyi Chen, Min Zhou, Shengrong Lou, Xin Li, Limin Zeng, and Keding Lu
Atmos. Chem. Phys., 25, 3905–3918, https://doi.org/10.5194/acp-25-3905-2025, https://doi.org/10.5194/acp-25-3905-2025, 2025
Short summary
Short summary
This study reports an observation of organic nitrate (including total peroxy nitrates and total alkyl nitrates) in Shanghai, China, during the summer of 2021, by homemade thermal dissociation cavity-enhanced absorption spectroscopy (TD-CEAS; Atmos. Meas. Tech., 14, 4033–4051, 2021). The distribution of organic nitrates and their effects on local ozone production are analyzed based on field observations in conjunction with model simulations.
Xudong Zheng and Shaodong Xie
Atmos. Chem. Phys., 25, 3807–3820, https://doi.org/10.5194/acp-25-3807-2025, https://doi.org/10.5194/acp-25-3807-2025, 2025
Short summary
Short summary
To reduce uncertainties in identifying the key volatile organic compounds (VOCs) in ozone (O3) formation from ambient concentrations, this study comprehensively calculates the emitted VOC concentrations during both nighttime and daytime using the nitrate radical, O3, and hydroxyl radical reaction rates and ambient VOC concentrations. Based on the emitted concentrations, isoprene is one of the top three species contributing to O3 formation, which may be overlooked in observed concentrations.
Sina Hasheminassab, David M. Tratt, Olga V. Kalashnikova, Clement S. Chang, Morad Alvarez, Kerry N. Buckland, Michael J. Garay, Francesca M. Hopkins, Eric R. Keim, Le Kuai, Yaning Miao, Payam Pakbin, William C. Porter, and Mohammad H. Sowlat
EGUsphere, https://doi.org/10.5194/egusphere-2025-1378, https://doi.org/10.5194/egusphere-2025-1378, 2025
Short summary
Short summary
Ammonia (NH3) is a key air pollutant linked to fine particle pollution, yet its sources remain poorly understood. Using airborne infrared imaging and ground sensors, we mapped NH3 emissions in California’s Salton Sea region with unprecedented detail. We found high emissions from farms, geothermal plants, and waste sites, including sources missing from inventories. These findings highlight the need for better NH3 monitoring to improve air quality models and guide pollution reduction strategies.
Mingxue Li, Men Xia, Chunshui Lin, Yifan Jiang, Weihang Sun, Yurun Wang, Yingnan Zhang, Maoxia He, and Tao Wang
Atmos. Chem. Phys., 25, 3753–3764, https://doi.org/10.5194/acp-25-3753-2025, https://doi.org/10.5194/acp-25-3753-2025, 2025
Short summary
Short summary
Our field campaigns observed a strong diel pattern of chloroacetic acid as well as a strong correlation between its level and that of reactive chlorine species at a coastal site. Using quantum chemical calculations and box model simulation with an updated Master Chemical Mechanism, we found that the formation pathway of chloroacetic acid involved multiphase processes. Our study enhances understanding of atmospheric organic chlorine chemistry and emphasizes the importance of multiphase reactions.
Renzhi Hu, Guoxian Zhang, Haotian Cai, Jingyi Guo, Keding Lu, Xin Li, Shengrong Lou, Zhaofeng Tan, Changjin Hu, Pinhua Xie, and Wenqing Liu
Atmos. Chem. Phys., 25, 3011–3028, https://doi.org/10.5194/acp-25-3011-2025, https://doi.org/10.5194/acp-25-3011-2025, 2025
Short summary
Short summary
A full suite of radical measurements (OH, HO2, RO2, and kOH) was established to accurately elucidate the limitations of oxidation in a chemically complex atmosphere. Sensitivity tests revealed that the incorporation of complex processes enabled a balance in both radical concentrations and coordinate ratios, effectively addressing the deficiency in the ozone generation mechanism. The full-chain radical detection bridged the gap between the photochemistry and the intensive oxidation level.
Yanjie Lu, Xinxin Feng, Yanli Feng, Minjun Jiang, Yu Peng, Tian Chen, and Yingjun Chen
EGUsphere, https://doi.org/10.5194/egusphere-2025-131, https://doi.org/10.5194/egusphere-2025-131, 2025
Short summary
Short summary
The EFs of CCs from biomass burning (BB) is an order of magnitude higher than that from on-road sources. Fuel type determines the emission characteristics and composition of CCs. The formation of CCs from solid and liquid fuel sources is respectively controlled by combustion temperature and emission standards. In addition, biomass burning and agricultural machinery sources significantly contribute to the oxidizing capacity of regional atmospheres.
Shuwen Guo, Xuan Zheng, Xiao He, Lewei Zeng, Liqiang He, Xian Wu, Yifei Dai, Zihao Huang, Ting Chen, Shupei Xiao, Yan You, Sheng Xiang, Shaojun Zhang, Jingkun Jiang, and Ye Wu
Atmos. Chem. Phys., 25, 2695–2705, https://doi.org/10.5194/acp-25-2695-2025, https://doi.org/10.5194/acp-25-2695-2025, 2025
Short summary
Short summary
We considered two potential influencing factors of heavy-duty diesel vehicle emissions that are rarely mentioned in the literature: cumulative mileage and ambient temperatures. The results suggest that prolonged use of heavy-duty diesel vehicles and low ambient temperatures leads to reduced engine combustion efficiency, which in turn increases tailpipe emissions significantly.
Junling Li, Chaofan Lian, Mingyuan Liu, Hao Zhang, Yongxin Yan, Yufei Song, Chun Chen, Jiaqi Wang, Haijie Zhang, Yanqin Ren, Yucong Guo, Weigang Wang, Yisheng Xu, Hong Li, Jian Gao, and Maofa Ge
Atmos. Chem. Phys., 25, 2551–2568, https://doi.org/10.5194/acp-25-2551-2025, https://doi.org/10.5194/acp-25-2551-2025, 2025
Short summary
Short summary
As a key source of hydroxyl (OH) radical, nitrous acid (HONO) has attracted much attention for its important role in the atmospheric oxidant capacity (AOC) increase. In this study, we made a comparison of the ambient levels, variation patterns, sources, and formation pathway in the warm season on the basis of continuous intensive observations at an urban site of Beijing. This work highlights the importance of HONO for the AOC in the warm season.
Xiao-Bing Li, Bin Yuan, Yibo Huangfu, Suxia Yang, Xin Song, Jipeng Qi, Xianjun He, Sihang Wang, Yubin Chen, Qing Yang, Yongxin Song, Yuwen Peng, Guiqian Tang, Jian Gao, Dasa Gu, and Min Shao
Atmos. Chem. Phys., 25, 2459–2472, https://doi.org/10.5194/acp-25-2459-2025, https://doi.org/10.5194/acp-25-2459-2025, 2025
Short summary
Short summary
Online vertical gradient measurements of volatile organic compounds (VOCs), ozone, and NOx were conducted based on a 325 m tall tower in urban Beijing. Vertical changes in the concentrations, compositions, key drivers, and environmental impacts of VOCs were analyzed in this study. We find that VOC species display differentiated vertical variation patterns and distinct roles in contributing to photochemical ozone formation with increasing height in the urban planetary boundary layer.
Alina Fiehn, Maximilian Eckl, Magdalena Pühl, Tiziana Bräuer, Klaus-Dirk Gottschaldt, Heinfried Aufmhoff, Lisa Eirenschmalz, Gregor Neumann, Felicitas Sakellariou, Daniel Sauer, Robert Baumann, Guilherme De Aguiar Ventura, Winne Nayole Cadete, Dário Luciano Zua, Manuel Xavier, Paulo Correia, and Anke Roiger
EGUsphere, https://doi.org/10.5194/egusphere-2025-635, https://doi.org/10.5194/egusphere-2025-635, 2025
Short summary
Short summary
In September 2022, the METHANE-To-Go Africa (MTGA) campaign, part of UNEP’s IMEO Methane Science Studies, conducted the first CH₄ emissions measurements from West Africa’s offshore oil and gas sector. Using an aircraft-based mass balance method, emissions from Angolan offshore facilities were quantified. Older, low-producing facilities showed higher emissions than newer ones. High-emission events were observed, highlighting the need for targeted monitoring and mitigation efforts.
Shigeyuki Ishidoya, Satoshi Sugawara, and Atsushi Okazaki
Atmos. Chem. Phys., 25, 1965–1987, https://doi.org/10.5194/acp-25-1965-2025, https://doi.org/10.5194/acp-25-1965-2025, 2025
Short summary
Short summary
The 18O/16O ratio of atmospheric oxygen, δatm(18O), is higher than that of ocean water due to isotopic effects during biospheric activities. This is known as the Dole–Morita effect, and its millennial-scale variations are recorded in ice cores. However, small variations of δatm(18O) in the present day have never been detected so far. This paper presents the first observations of diurnal, seasonal, and secular variations in δatm(18O) and applies them to evaluate oxygen, carbon, and water cycles.
Delaney B. Kilgour, Christopher M. Jernigan, Olga Garmash, Sneha Aggarwal, Shengqian Zhou, Claudia Mohr, Matt E. Salter, Joel A. Thornton, Jian Wang, Paul Zieger, and Timothy H. Bertram
Atmos. Chem. Phys., 25, 1931–1947, https://doi.org/10.5194/acp-25-1931-2025, https://doi.org/10.5194/acp-25-1931-2025, 2025
Short summary
Short summary
We report simultaneous measurements of dimethyl sulfide (DMS) and hydroperoxymethyl thioformate (HPMTF) in the eastern North Atlantic. We use an observationally constrained box model to show that cloud loss is the dominant sink of HPMTF in this region over 6 weeks, resulting in large reductions in DMS-derived products that contribute to aerosol formation and growth. Our findings indicate that fast cloud processing of HPMTF must be included in global models to accurately capture the sulfur cycle.
Jiemeng Bao, Xin Zhang, Zhenhai Wu, Li Zhou, Jun Qian, Qinwen Tan, Fumo Yang, Junhui Chen, Yunfeng Li, Hefan Liu, Liqun Deng, and Hong Li
Atmos. Chem. Phys., 25, 1899–1916, https://doi.org/10.5194/acp-25-1899-2025, https://doi.org/10.5194/acp-25-1899-2025, 2025
Short summary
Short summary
We studied carbonyl compounds' role in ozone pollution in the Chengdu Plain Urban Agglomeration, China. During heavy pollution in August 2019, we measured carbonyls at nine sites and analyzed their impact. Areas with higher carbonyl levels, like Chengdu, had worse ozone pollution. While their abundance matters, chemical reactions with other pollutants are the main drivers. Our findings show regional cooperation is vital to reducing ozone pollution effectively.
Masahito Ueyama, Taku Umezawa, Yukio Terao, Mark Lunt, and James Lawrence France
EGUsphere, https://doi.org/10.5194/egusphere-2024-3926, https://doi.org/10.5194/egusphere-2024-3926, 2025
Short summary
Short summary
Methane (CH4) emissions were measured in Megacity Osaka, Japan, using mobile and eddy covariance methods. The CH4 emissions were much higher than those reported in local inventories, with natural gas contributing up to 74 % of the emissions. Several CH4 sources not accounted for in current inventories were identified. These results emphasize the need for more comprehensive emissions tracking in urban areas to enhance climate change mitigation efforts.
Yaru Wang, Dominik van Pinxteren, Andreas Tilgner, Erik Hans Hoffmann, Max Hell, Susanne Bastian, and Hartmut Herrmann
EGUsphere, https://doi.org/10.5194/egusphere-2024-4202, https://doi.org/10.5194/egusphere-2024-4202, 2025
Short summary
Short summary
Tropospheric ground-level ozone (O3) is a global air-quality pollutant and greenhouse gas. Long-term O3 trends from 16 stations in Saxony, Germany, were compared over three periods, revealing worsened O3 pollution over the last decade. O3 formation has been volatile organic compound (VOC)-limited at traffic and urban sites for the past 20 years. To mitigate O3 pollution, moderate nitrogen oxides and additional VOC controls, particularly in solvent use, should be prioritized in the coming years.
Baoye Hu, Naihua Chen, Rui Li, Mingqiang Huang, Jinsheng Chen, Youwei Hong, Lingling Xu, Xiaolong Fan, Mengren Li, Lei Tong, Qiuping Zheng, and Yuxiang Yang
Atmos. Chem. Phys., 25, 905–921, https://doi.org/10.5194/acp-25-905-2025, https://doi.org/10.5194/acp-25-905-2025, 2025
Short summary
Short summary
Box modeling with the Master Chemical Mechanism (MCM) was used to explore summertime peroxyacetyl nitrate (PAN) formation and its link to aerosol pollution under high-ozone conditions. The MCM model is effective in the study of PAN photochemical formation and performed better during the clean period than the haze period. Machine learning analysis identified ammonia, nitrate, and fine particulate matter as the top three factors contributing to simulation bias.
Xiansheng Liu, Xun Zhang, Marvin Dufresne, Tao Wang, Lijie Wu, Rosa Lara, Roger Seco, Marta Monge, Ana Maria Yáñez-Serrano, Marie Gohy, Paul Petit, Audrey Chevalier, Marie-Pierre Vagnot, Yann Fortier, Alexia Baudic, Véronique Ghersi, Grégory Gille, Ludovic Lanzi, Valérie Gros, Leïla Simon, Heidi Héllen, Stefan Reimann, Zoé Le Bras, Michelle Jessy Müller, David Beddows, Siqi Hou, Zongbo Shi, Roy M. Harrison, William Bloss, James Dernie, Stéphane Sauvage, Philip K. Hopke, Xiaoli Duan, Taicheng An, Alastair C. Lewis, James R. Hopkins, Eleni Liakakou, Nikolaos Mihalopoulos, Xiaohu Zhang, Andrés Alastuey, Xavier Querol, and Thérèse Salameh
Atmos. Chem. Phys., 25, 625–638, https://doi.org/10.5194/acp-25-625-2025, https://doi.org/10.5194/acp-25-625-2025, 2025
Short summary
Short summary
This study examines BTEX (benzene, toluene, ethylbenzene, xylenes) pollution in urban areas across seven European countries. Analyzing data from 22 monitoring sites, we found traffic and industrial activities significantly impact BTEX levels, with peaks during rush hours. The risk from BTEX exposure remains moderate, especially in high-traffic and industrial zones, highlighting the need for targeted air quality management to protect public health and improve urban air quality.
Yuening Li, Faqiang Zhan, Chubashini Shunthirasingham, Ying Duan Lei, Jenny Oh, Amina Ben Chaaben, Zhe Lu, Kelsey Lee, Frank A. P. C. Gobas, Hayley Hung, and Frank Wania
Atmos. Chem. Phys., 25, 459–472, https://doi.org/10.5194/acp-25-459-2025, https://doi.org/10.5194/acp-25-459-2025, 2025
Short summary
Short summary
Organophosphate esters are important humanmade trace contaminants. Measuring them in the atmospheric gas phase, particles, precipitation, and surface water in Canada, we explore seasonal concentration variability, gas–particle partitioning, precipitation scavenging, and the air–water equilibrium. Whereas higher summer concentrations and efficient precipitation scavenging conform with expectations, the lack of a relationship between compound volatility and gas–particle partitioning is puzzling.
Markus Jesswein, Valentin Lauther, Nicolas Emig, Peter Hoor, Timo Keber, Hans-Christoph Lachnitt, Linda Ort, Tanja Schuck, Johannes Strobel, Ronja Van Luijt, C. Michael Volk, Franziska Weyland, and Andreas Engel
EGUsphere, https://doi.org/10.5194/egusphere-2024-3946, https://doi.org/10.5194/egusphere-2024-3946, 2025
Short summary
Short summary
The study investigates transport within the Asian Summer Monsoon, focussing on how CH2Cl2 reaches the subarctic tropopause region. Using data from the PHILEAS campaign in 2023, events with increased mixing ratios were detected. Their origin, the transport paths to the tropopause region and the potential entry into the stratosphere were analysed. The East Asian Summer Monsoon was identified as the main transport pathway, with only a small contribution to the stratosphere in the following days.
Fanhao Meng, Baobin Han, Min Qin, Wu Fang, Ke Tang, Dou Shao, Zhitang Liao, Jun Duan, Yan Feng, Yong Huang, Ting Ni, and Pinhua Xie
Atmos. Chem. Phys., 24, 14191–14208, https://doi.org/10.5194/acp-24-14191-2024, https://doi.org/10.5194/acp-24-14191-2024, 2024
Short summary
Short summary
Comprehensive observations of HONO and NOx fluxes were conducted over paddy fields in the Huaihe River Basin. Consecutive peaks in HONO and NO fluxes suggest a potentially enhanced release of HONO and NO due to soil tillage, whereas waterlogged soil may inhibit microbial nitrification processes following irrigation. Notably, biological processes and light-driven NO2 reactions at the surface may serve as sources of HONO and influence the local HONO budget during rotary tillage.
Rodrigo J. Seguel, Charlie Opazo, Yann Cohen, Owen R. Cooper, Laura Gallardo, Björn-Martin Sinnhuber, Florian Obersteiner, Andreas Zahn, Peter Hoor, and Susanne Rohs
EGUsphere, https://doi.org/10.5194/egusphere-2024-3719, https://doi.org/10.5194/egusphere-2024-3719, 2024
Short summary
Short summary
We explored differences in ozone levels between the Northern and Southern Hemispheres in the Stratosphere-troposphere exchange region. Using unique data from a research aircraft, we found significantly lower ozone levels (with stratospheric character) in the Southern Hemisphere, especially during years of severe ozone depletion. A Sudden Stratospheric Warming event in 2019 increased Southern Hemisphere ozone levels, highlighting the relationship between atmospheric events and ozone distribution.
Zhaojin An, Rujing Yin, Xinyan Zhao, Xiaoxiao Li, Yuyang Li, Yi Yuan, Junchen Guo, Yiqi Zhao, Xue Li, Dandan Li, Yaowei Li, Dongbin Wang, Chao Yan, Kebin He, Douglas R. Worsnop, Frank N. Keutsch, and Jingkun Jiang
Atmos. Chem. Phys., 24, 13793–13810, https://doi.org/10.5194/acp-24-13793-2024, https://doi.org/10.5194/acp-24-13793-2024, 2024
Short summary
Short summary
Online Vocus-PTR measurements show the compositions and seasonal variations in organic vapors in urban Beijing. With enhanced sensitivity and mass resolution, various species at a level of sub-parts per trillion (ppt) and organics with multiple oxygens (≥ 3) were observed. The fast photooxidation process in summer leads to an increase in both concentration and proportion of organics with multiple oxygens, while, in other seasons, the variations in them could be influenced by mixed sources.
Ross Charles Petersen, Thomas Holst, Cheng Wu, Radovan Krejci, Jeremy Chan, Claudia Mohr, and Janne Rinne
EGUsphere, https://doi.org/10.5194/egusphere-2024-3410, https://doi.org/10.5194/egusphere-2024-3410, 2024
Short summary
Short summary
Ecosystem-scale emissions of biogenic volatile organic compounds (BVOCs) are important for atmospheric chemistry. Here we investigate boreal BVOC fluxes from a forest in central Sweden. BVOC fluxes were measured above-canopy using proton-transfer-reaction mass spectrometry, while compound-specific monoterpene (MT) fluxes were assessed using a concentration gradient method. We also evaluate the impact of chemical degradation on observed sesquiterpene (SQT) and nighttime MT fluxes.
Bowen Zhang, Dong Zhang, Zhe Dong, Xinshuai Song, Ruiqin Zhang, and Xiao Li
Atmos. Chem. Phys., 24, 13587–13601, https://doi.org/10.5194/acp-24-13587-2024, https://doi.org/10.5194/acp-24-13587-2024, 2024
Short summary
Short summary
To gain insight into the impact of changes due to epidemic control policies, we undertook continuous online monitoring of volatile organic compounds (VOCs) at an urban site in Zhengzhou over a 2-month period. This study examines the characteristics of VOCs, their sources, and their temporal evolution. It also assesses the impact of the policy change on VOC pollution during the monitoring period, thus providing a basis for further research on VOC pollution and source control.
Jakob Boyd Pernov, Jens Liengaard Hjorth, Lise Lotte Sørensen, and Henrik Skov
Atmos. Chem. Phys., 24, 13603–13631, https://doi.org/10.5194/acp-24-13603-2024, https://doi.org/10.5194/acp-24-13603-2024, 2024
Short summary
Short summary
Arctic ozone depletion events (ODEs) occur every spring and have vast implications for the oxidizing capacity, radiative balance, and mercury oxidation. In this study, we analyze ozone, ODEs, and their connection to meteorological and air mass history variables through statistical analyses, back trajectories, and machine learning (ML) at Villum Research Station. ODEs are favorable under sunny, calm conditions with air masses arriving from northerly wind directions with sea ice contact.
Hagninou Elagnon Venance Donnou, Aristide Barthélémy Akpo, Money Ossohou, Claire Delon, Véronique Yoboué, Dungall Laouali, Marie Ouafo-Leumbe, Pieter Gideon Van Zyl, Ousmane Ndiaye, Eric Gardrat, Maria Dias-Alves, and Corinne Galy-Lacaux
Atmos. Chem. Phys., 24, 13151–13182, https://doi.org/10.5194/acp-24-13151-2024, https://doi.org/10.5194/acp-24-13151-2024, 2024
Short summary
Short summary
Ozone is a secondary air pollutant that is detrimental to human and plant health. A better understanding of its chemical evolution is a challenge for Africa, where it is still undersampled. Out of 14 sites examined (1995–2020), high levels of O3 are reported in southern Africa. The dominant chemical processes leading to O3 formation are identified. A decrease in O3 is observed at Katibougou (Mali) and Banizoumbou (Niger), and an increase is found at Zoétélé (Cameroon) and Skukuza (South Africa).
Junwei Song, Georgios I. Gkatzelis, Ralf Tillmann, Nicolas Brüggemann, Thomas Leisner, and Harald Saathoff
Atmos. Chem. Phys., 24, 13199–13217, https://doi.org/10.5194/acp-24-13199-2024, https://doi.org/10.5194/acp-24-13199-2024, 2024
Short summary
Short summary
Biogenic volatile organic compounds (BVOCs) and organic aerosol (OA) particles were measured online in a stressed spruce-dominated forest. OA was mainly attributed to the monoterpene oxidation products. The mixing ratios of BVOCs were higher than the values previously measured in other temperate forests. The results demonstrate that BVOCs are influenced not only by meteorology and biogenic emissions but also by local anthropogenic emissions and subsequent chemical transformation processes.
Sachin Mishra, Vinayak Sinha, Haseeb Hakkim, Arpit Awasthi, Sachin D. Ghude, Vijay Kumar Soni, Narendra Nigam, Baerbel Sinha, and Madhavan N. Rajeevan
Atmos. Chem. Phys., 24, 13129–13150, https://doi.org/10.5194/acp-24-13129-2024, https://doi.org/10.5194/acp-24-13129-2024, 2024
Short summary
Short summary
We quantified 111 gases using mass spectrometry to understand how seasonal and emission changes lead from clean air in the monsoon season to extremely polluted air in the post-monsoon season in Delhi. Averaged total mass concentrations (260 µg m-3) were > 4 times in polluted periods, driven by biomass burning emissions and reduced atmospheric ventilation. Reactive gaseous nitrogen, chlorine, and sulfur compounds hitherto unreported from such a polluted environment were discovered.
Gérard Ancellet, Camille Viatte, Anne Boynard, François Ravetta, Jacques Pelon, Cristelle Cailteau-Fischbach, Pascal Genau, Julie Capo, Axel Roy, and Philippe Nédélec
Atmos. Chem. Phys., 24, 12963–12983, https://doi.org/10.5194/acp-24-12963-2024, https://doi.org/10.5194/acp-24-12963-2024, 2024
Short summary
Short summary
Characterization of ozone pollution in urban areas benefited from a measurement campaign in summer 2022 in the Paris region. The analysis is based on 21 d of lidar and aircraft observations. The main objective is an analysis of the sensitivity of ozone pollution to the micrometeorological processes in the urban atmospheric boundary layer and the transport of regional pollution. The paper also discusses to what extent satellite observations can track observed ozone plumes.
Xiaoyi Zhang, Wanyun Xu, Weili Lin, Gen Zhang, Jinjian Geng, Li Zhou, Huarong Zhao, Sanxue Ren, Guangsheng Zhou, Jianmin Chen, and Xiaobin Xu
Atmos. Chem. Phys., 24, 12323–12340, https://doi.org/10.5194/acp-24-12323-2024, https://doi.org/10.5194/acp-24-12323-2024, 2024
Short summary
Short summary
Ozone (O3) deposition is a key process that removes surface O3, affecting air quality, ecosystems and climate change. We conducted O3 deposition measurement over a wheat canopy using a newly relaxed eddy accumulation flux system. Large variabilities in O3 deposition were detected, mainly determined by crop growth and modulated by various environmental factors. More O3 deposition observations over different surfaces are needed for exploring deposition mechanisms and model optimization.
Honglei Wang, David W. Tarasick, Jane Liu, Herman G. J. Smit, Roeland Van Malderen, Lijuan Shen, Romain Blot, and Tianliang Zhao
Atmos. Chem. Phys., 24, 11927–11942, https://doi.org/10.5194/acp-24-11927-2024, https://doi.org/10.5194/acp-24-11927-2024, 2024
Short summary
Short summary
In this study, we identify 23 suitable pairs of sites from World Ozone and Ultraviolet Radiation Data Centre (WOUDC) and In-service Aircraft for a Global Observing System (IAGOS) datasets (1995 to 2021), compare the average vertical distributions of tropospheric O3 from ozonesonde and aircraft measurements, and analyze the differences based on ozonesonde type and station–airport distance.
Noémie Taquet, Wolfgang Stremme, María Eugenia González del Castillo, Victor Almanza, Alejandro Bezanilla, Olivier Laurent, Carlos Alberti, Frank Hase, Michel Ramonet, Thomas Lauvaux, Ke Che, and Michel Grutter
Atmos. Chem. Phys., 24, 11823–11848, https://doi.org/10.5194/acp-24-11823-2024, https://doi.org/10.5194/acp-24-11823-2024, 2024
Short summary
Short summary
We characterize the variability in CO and CO2 emissions over Mexico City from long-term time-resolved Fourier transform infrared spectroscopy solar absorption and surface measurements from 2013 to 2021. Using the average intraday CO growth rate from total columns, the average CO / CO2 ratio and TROPOMI data, we estimate the interannual variability in the CO and CO2 anthropogenic emissions of Mexico City, highlighting the effect of an unprecedented drop in activity due to the COVID-19 lockdown.
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.
Theresa Harlass, Rebecca Dischl, Stefan Kaufmann, Raphael Märkl, Daniel Sauer, Monika Scheibe, Paul Stock, Tiziana Bräuer, Andreas Dörnbrack, Anke Roiger, Hans Schlager, Ulrich Schumann, Magdalena Pühl, Tobias Schripp, Tobias Grein, Linda Bondorf, Charles Renard, Maxime Gauthier, Mark Johnson, Darren Luff, Paul Madden, Peter Swann, Denise Ahrens, Reetu Sallinen, and Christiane Voigt
Atmos. Chem. Phys., 24, 11807–11822, https://doi.org/10.5194/acp-24-11807-2024, https://doi.org/10.5194/acp-24-11807-2024, 2024
Short summary
Short summary
Emissions from aircraft have a direct impact on our climate. Here, we present airborne and ground-based measurement data of nitrogen oxides that were collected in the exhaust of an Airbus aircraft. We study the impact of burning fossil and sustainable aviation fuel on nitrogen oxide emissions at different engine settings related to combustor temperature, pressure and fuel flow. Further, we compare observations with engine emission models.
Zhouxing Zou, Tianshu Chen, Qianjie Chen, Weihang Sun, Shichun Han, Zhuoyue Ren, Xinyi Li, Wei Song, Aoqi Ge, Qi Wang, Xiao Tian, Chenglei Pei, Xinming Wang, Yanli Zhang, and Tao Wang
EGUsphere, https://doi.org/10.5194/egusphere-2024-3210, https://doi.org/10.5194/egusphere-2024-3210, 2024
Short summary
Short summary
We measured ambient OH and HO2 concentrations at a subtropical rural site and compared our observations with model results. During warm periods, the model overestimated the concentrations of OH and HO2, leading to overestimation of ozone and nitric acid production. Our findings highlight the need to better understand how OH and HO2are formed and removed, which is important for accurate air quality and climate predictions.
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.
Lee Tiszenkel, James H. Flynn, and Shan-Hu Lee
Atmos. Chem. Phys., 24, 11351–11363, https://doi.org/10.5194/acp-24-11351-2024, https://doi.org/10.5194/acp-24-11351-2024, 2024
Short summary
Short summary
Ammonia and amines are important ingredients for aerosol formation in urban environments, but the measurements of these compounds are extremely challenging. Our observations show that urban ammonia and amines in Houston are emitted from urban sources, and diurnal variations in their concentrations are likely governed by gas-to-particle conversion and emissions.
Arpit Awasthi, Baerbel Sinha, Haseeb Hakkim, Sachin Mishra, Varkrishna Mummidivarapu, Gurmanjot Singh, Sachin D. Ghude, Vijay Kumar Soni, Narendra Nigam, Vinayak Sinha, and Madhavan N. Rajeevan
Atmos. Chem. Phys., 24, 10279–10304, https://doi.org/10.5194/acp-24-10279-2024, https://doi.org/10.5194/acp-24-10279-2024, 2024
Short summary
Short summary
We use 111 volatile organic compounds (VOCs), PM10, and PM2.5 in a positive matrix factorization (PMF) model to resolve 11 pollution sources validated with chemical fingerprints. Crop residue burning and heating account for ~ 50 % of the PM, while traffic and industrial emissions dominate the gas-phase VOC burden and formation potential of secondary organic aerosols (> 60 %). Non-tailpipe emissions from compressed-natural-gas-fuelled commercial vehicles dominate the transport sector's PM burden.
Luke D. Schiferl, Cong Cao, Bronte Dalton, Andrew Hallward-Driemeier, Ricardo Toledo-Crow, and Róisín Commane
Atmos. Chem. Phys., 24, 10129–10142, https://doi.org/10.5194/acp-24-10129-2024, https://doi.org/10.5194/acp-24-10129-2024, 2024
Short summary
Short summary
Carbon monoxide (CO) is an air pollutant and an important indicator of the incomplete combustion of fossil fuels in cities. Using 4 years of winter and spring observations in New York City, we found that both the magnitude and variability of CO from the metropolitan area are greater than expected. Transportation emissions cannot explain the missing and variable CO, which points to energy from buildings as a likely underappreciated source of urban air pollution and greenhouse gas emissions.
Chengzhi Xing, Cheng Liu, Chunxiang Ye, Jingkai Xue, Hongyu Wu, Xiangguang Ji, Jinping Ou, and Qihou Hu
Atmos. Chem. Phys., 24, 10093–10112, https://doi.org/10.5194/acp-24-10093-2024, https://doi.org/10.5194/acp-24-10093-2024, 2024
Short summary
Short summary
We identified the contributions of ozone (O3) and nitrous acid (HONO) to the production rates of hydroxide (OH) in vertical space on the Tibetan Plateau (TP). A new insight was offered: the contributions of HONO and O3 to the production rates of OH on the TP are even greater than in lower-altitudes areas. This study enriches the understanding of vertical distribution of atmospheric components and explains the strong atmospheric oxidation capacity (AOC) on the TP.
Xinyuan Zhang, Lingling Wang, Nan Wang, Shuangliang Ma, Shenbo Wang, Ruiqin Zhang, Dong Zhang, Mingkai Wang, and Hongyu Zhang
Atmos. Chem. Phys., 24, 9885–9898, https://doi.org/10.5194/acp-24-9885-2024, https://doi.org/10.5194/acp-24-9885-2024, 2024
Short summary
Short summary
This study highlights the importance of the redox reaction of NO2 with SO2 based on actual atmospheric observations. The particle pH in future China is expected to rise steadily. Consequently, this reaction could become a significant source of HONO in China. Therefore, it is crucial to coordinate the control of SO2, NOx, and NH3 emissions to avoid a rapid increase in the particle pH.
Cited articles
Balashov, N. V., Thompson, A. M., Piketh, S. J., and Langerman, K. E.: Surface ozone variability and trends over the South African Highveld from 1990 to 2007, J. Geophys. Res.-Atmos., 119, 4323–4342, https://doi.org/10.1002/2013jd020555, 2014.
Baldy, S., Ancellet, G., Bessafi, M., Badr, A., and Luk, D. L. S.: Field observations of the vertical distribution of tropospheric ozone at the island of Reunion (southern tropics), J. Geophys. Res.-Atmos., 101, 23835–23849, https://doi.org/10.1029/95jd02929, 1996.
Baray, J. L., Ancellet, G., Taupin, F. G., Bessafi, M., Baldy, S., and Keckhut, P.: Subtropical tropopause break as a possible stratospheric source of ozone in the tropical troposphere, J. Atmos. Sol.-Terr. Phy., 60, 27–36, https://doi.org/10.1016/S1364-6826(97)00116-8, 1998.
Baray, J. L., Leveau, J., Baldy, S., Jouzel, J., Keckhut, P., Bergametti, G., Ancellet, G., Bencherif, H., Cadet, B., Carleer, M., David, C., De Maziere, M., Faduilhe, D., Beekmann, S. G., Goloub, P., Goutail, F., Metzger, J. M., Morel, B., Pommereau, J. P., Porteneuve, J., Portafaix, T., Posny, F., Robert, L., and Van Roozendael, M.: An instrumented station for the survey of ozone and climate change in the southern tropics, J. Environ. Monitor., 8, 1020–1028, https://doi.org/10.1039/b607762e, 2006.
Beekmann, M., Ancellet, G., and Megie, G.: Climatology of tropospheric ozone in southern Europe and its relation to potential vorticity, J. Geophys. Res.-Atmos., 99, 12841–12853, https://doi.org/10.1029/94jd00228, 1994.
Beig, G. and Singh, V.: Trends in tropical tropospheric column ozone from satellite data and MOZART model, Geophys. Res. Lett., 34, L17801, https://doi.org/10.1029/2007gl030460, 2007.
Brunekreef, B. and Holgate, S. T.: Air pollution and health, The Lancet, 360, 1233–1242, 2002.
Chandra, S., Ziemke, J. R., Min, W., and Read, W. G.: Effects of 1997–1998 El Niño on tropospheric ozone and water vapor, Geophys. Res. Lett., 25, 3867–3870, https://doi.org/10.1029/98gl02695, 1998.
Chatfield, R. B., Guan, H., Thompson, A. M., and Witte, J. C.: Convective lofting links Indian Ocean air pollution to paradoxical South Atlantic ozone maxima, Geophys. Res. Lett., 31, L06103, https://doi.org/10.1029/2003gl018866, 2004.
Clain, G., Baray, J. L., Delmas, R., Diab, R., Leclair de Bellevue, J., Keckhut, P., Posny, F., Metzger, J. M., and Cammas, J. P.: Tropospheric ozone climatology at two Southern Hemisphere tropical/subtropical sites, (Reunion Island and Irene, South Africa) from ozonesondes, LIDAR, and in situ aircraft measurements, Atmos. Chem. Phys., 9, 1723–1734, https://doi.org/10.5194/acp-9-1723-2009, 2009.
Clain, G., Baray, J. L., Delmas, R., Keckhut, P., and Cammas, J. P.: A lagrangian approach to analyse the tropospheric ozone climatology in the tropics: Climatology of stratosphere-troposphere exchange at Reunion Island, Atmos. Environ., 44, 968–975, https://doi.org/10.1016/j.atmosenv.2009.08.048, 2010.
Collins, W. J., Derwent, R. G., Johnson, C. E., and Stevenson, D. S.: The impact of human activities on the photochemical production and destruction of tropospheric ozone, Q. J. Roy. Meteor. Soc., 126, 1925–1951, https://doi.org/10.1256/smsqj.56618, 2000.
Collins, W. J., Derwent, R. G., Garnier, B., Johnson, C. E., Sanderson, M. G., and Stevenson, D. S.: Effect of stratosphere-troposphere exchange on the future tropospheric ozone trend, J. Geophys. Res.-Atmos., 108, 8528, https://doi.org/10.1029/2002jd002617, 2003.
Cooper, O. R., Gao, R. S., Tarasick, D., Leblanc, T., and Sweeney, C.: Long-term ozone trends at rural ozone monitoring sites across the United States, 1990–2010, J. Geophys. Res.-Atmos., 117, D22307, https://doi.org/10.1029/2012jd018261, 2012.
Dee, D. P., Uppala, S. M., Simmons, A. J., Berrisford, P., Poli, P., Kobayashi, S., Andrae, U., Balmaseda, M. A., Balsamo, G., Bauer, P., Bechtold, P., Beljaars, A. C. M., van de Berg, L., Bidlot, J., Bormann, N., Delsol, C., Dragani, R., Fuentes, M., Geer, A. J., Haimberger, L., Healy, S. B., Hersbach, H., Holm, E. V., Isaksen, L., Kallberg, P., Kohler, M., Matricardi, M., McNally, A. P., Monge-Sanz, B. M., Morcrette, J. J., Park, B. K., Peubey, C., de Rosnay, P., Tavolato, C., Thepaut, J. N., and Vitart, F.: The ERA-Interim reanalysis: configuration and performance of the data assimilation system, Q. J. Roy. Meteor. Soc., 137, 553–597, https://doi.org/10.1002/qj.828, 2011.
Diab, R. D., Thompson, A. M., Zunckel, M., Coetzee, G. J. R., Combrink, J., Bodeker, G. E., Fishman, J., Sokolic, F., McNamara, D. P., Archer, C. B., and Nganga, D.: Vertical ozone distribution over southern Africa and adjacent oceans during SAFARI-92, J. Geophys. Res.-Atmos., 101, 23823–23833, https://doi.org/10.1029/96jd01267, 1996.
Diab, R. D., Raghunandan, A., Thompson, A. M., and Thouret, V.: Classification of tropospheric ozone profiles over Johannesburg based on mozaic aircraft data, Atmos. Chem. Phys., 3, 713–723, https://doi.org/10.5194/acp-3-713-2003, 2003.
Diab, R. D., Thompson, A. M., Mari, K., Ramsay, L., and Coetzee, G. J. R.: Tropospheric ozone climatology over Irene, South Africa, from 1990 to 1994 and 1998 to 2002, J. Geophys. Res.-Atmos., 109, D20301, https://doi.org/10.1029/2004jd004793, 2004.
Doughty, D. C., Thompson, A. M., Schoeberl, M. R., Stajner, I., Wargan, K., and Hui, W. C. J.: An intercomparison of tropospheric ozone retrievals derived from two Aura instruments and measurements in western North America in 2006, J. Geophys. Res.-Atmos., 116, D06303, https://doi.org/10.1029/2010jd014703, 2011.
Duflot, V., Dils, B., Baray, J. L., De Maziere, M., Attie, J. L., Vanhaelewyn, G., Senten, C., Vigouroux, C., Clain, G., and Delmas, R.: Analysis of the origin of the distribution of CO in the subtropical southern Indian Ocean in 2007, J. Geophys. Res.-Atmos., 115, D22106, https://doi.org/10.1029/2010jd013994, 2010.
Duflot, V., Royer, P., Chazette, P., Baray, J. L., Courcoux, Y., and Delmas, R.: Marine and biomass burning aerosols in the southern Indian Ocean: Retrieval of aerosol optical properties from shipborne lidar and Sun photometer measurements, J. Geophys. Res.-Atmos., 116, D18208, https://doi.org/10.1029/2011jd015839, 2011.
Fishman, J., Watson, C. E., Larsen, J. C., and Logan, J. A.: Distribution of tropospheric ozone determined from satellite data, J. Geophys. Res.-Atmos., 95, 3599–3617, https://doi.org/10.1029/JD095iD04p03599, 1990.
Fishman, J., Fakhruzzaman, K., Cros, B., and Nganga, D.: Identification of Widespread Pollution in the Southern Hemisphere Deduced from Satellite Analyses, Science, 252, 1693–1696, https://doi.org/10.1126/science.252.5013.1693, 1991.
Fishman, J., Brackett, V. G., Browell, E. V., and Grant, W. B.: Tropospheric ozone derived from TOMS/SBUV measurements during TRACE A, J. Geophys. Res.-Atmos., 101, 24069–24082, https://doi.org/10.1029/95jd03576, 1996.
Fujiwara, M., Kita, K., Kawakami, S., Ogawa, T., Komala, N., Saraspriya, S., and Suripto, A.: Tropospheric ozone enhancements during the Indonesian Forest Fire Events in 1994 and in 1997 as revealed by ground-based observations, Geophys. Res. Lett., 26, 2417–2420, https://doi.org/10.1029/1999gl900117, 1999.
Gallardo, L., Alonso, M., Andrade, M. de F., Barreto Carvalho, V. S., Behrentz, E., de Castro Vasconcellos, P., D'Angiola, A., Dawidowski, L., Freitas, S., Gómez, D., Longo, K. M., Doprichinski Martins, L., Mena, M., Matus, P., Osses, A., Osses, M., Rojas, N., Saide, P., Sánchez-Ccoyllo, O., and Toro, M. V.: South America, in: WMO/IGAC Impacts Of Megacities On Air Pollution and Climate, edited by: Zhu, T., Melamed, M. L., Parrish, D., Gauss, M., Klenner, L. G., Lawrence, M., Konaré, A., and Liousse, C., World Meteorological Organization (WMO), Geneva, 28–58, 2012.
Garstang, M., Tyson, P. D., Swap, R., Edwards, M., Kållberg, P., and Lindesay, J. A.: Horizontal and vertical transport of air over southern Africa, J. Geophys. Res.-Atmos., 101, 23721–23736, https://doi.org/10.1029/95jd00844, 1996.
Heikes, B., Lee, M., Jacob, D., Talbot, R., Bradshaw, J., Singh, H., Blake, D., Anderson, B., Fuelberg, H., and Thompson, A. M.: Ozone, hydroperoxides, oxides of nitrogen, and hydrocarbon budgets in the marine boundary layer over the South Atlantic, J. Geophys. Res.-Atmos., 101, 24221–24234, https://doi.org/10.1029/95jd03631, 1996.
Holton, J. R., Haynes, P. H., McIntyre, M. E., Douglass, A. R., Rood, R. B., and Pfister, L.: Stratosphere-troposphere exchange, Rev. Geophys., 33, 403–439, https://doi.org/10.1029/95rg02097, 1995.
Jensen, A. A., Thompson, A. M., and Schmidlin, F. J.: Classification of Ascension Island and Natal ozonesondes using self-organizing maps, J. Geophys. Res.-Atmos., 117, D04302, https://doi.org/10.1029/2011jd016573, 2012.
Johnson, B. J., Oltmans, S. J., Vömel, H., Smit, H. G. J., Deshler, T., and Kröger, C.: Electrochemical concentration cell (ECC) ozonesonde pump efficiency measurements and tests on the sensitivity to ozone of buffered and unbuffered ECC sensor cathode solutions, J. Geophys. Res.-Atmos., 107, 4393, https://doi.org/10.1029/2001jd000557, 2002.
Kanyanga, J. K.: El Niño Southern Oscillation (ENSO) and Atmospheric Transport over Southern Africa, Unpublished PhD Thesis, University of Johannesburg, South Africa, 2008.
Keyser, D., and Shapiro, M. A.: A review of the structure and dynamics of upper-level frontal zones, Mon. Weather Rev., 114, 452–499, https://doi.org/10.1175/1520-0493(1986)114<0452:arotsa>2.0.co;2, 1986.
Lee, S., Shelow, D. M., Thompson, A. M., and Miller, S. K.: QBO and ENSO variability in temperature and ozone from SHADOZ, 1998–2005, J. Geophys. Res.-Atmos., 115, D18105, https://doi.org/10.1029/2009JD013320, 2010.
Liousse, C., Konaré, A., Kanakidou, M., and Pienaar, K.: Africa, in: WMO/IGAC Impacts Of Megacities On Air Pollution and Climate, edited by: Zhu, T., Melamed, M. L., Parrish, D., Gauss, M., Klenner, L. G., Lawrence, M., Konaré, A., and Liousse, C., World Meteorological Organization (WMO), Geneva, 28–58, 2012.
Liousse, C., Assamoi, E., Criqui, P., Granier, C., and Rosset, R.: Explosive growth in African combustion emissions from 2005 to 2030, Environn. Res. Lett., 9, 035003, https://doi.org/10.1088/1748-9326/9/3/035003, 2014.
Logan, J. A., Megretskaia, I., Nassar, R., Murray, L. T., Zhang, L., Bowman, K. W., Worden, H. M., and Luo, M.: Effects of the 2006 El Niño on tropospheric composition as revealed by data from the Tropospheric Emission Spectrometer (TES), Geophys. Res. Lett., 35, L03816, https://doi.org/10.1029/2007gl031698, 2008.
Logan, J. A., Staehelin, J., Megretskaia, I. A., Cammas, J. P., Thouret, V., Claude, H., De Backer, H., Steinbacher, M., Scheel, H. E., Stübi, R., Fröhlich, M., and Derwent, R.: Changes in ozone over Europe: Analysis of ozone measurements from sondes, regular aircraft (MOZAIC) and alpine surface sites, J. Geophys. Res.-Atmos., 117, D09301, https://doi.org/10.1029/2011jd016952, 2012.
Lourens, A. S., Beukes, J. P., van Zyl, P. G., Fourie, G. D., Burger, J. W., Pienaar, J. J., Read, C. E., and Jordaan, J. H.: Spatial and temporal assessment of gaseous pollutants in the Highveld of South Africa, S. Afr. J. Sci., 107, 55–62, https://doi.org/10.4102/sajs.v107i1/2.269, 2011.
Oltmans, S., Lefohn, A., Shadwick, D., Harris, J., Scheel, H., Galbally, I., Tarasick, D., Johnson, B., Brunke, E.-G., and Claude, H.: Recent tropospheric ozone changes – a pattern dominated by slow or no growth, Atmos. Environ., 67, 331–351, https://doi.org/10.1016/j.atmosenv.2012.10.057, 2013.
Oman, L. D., Ziemke, J. R., Douglass, A. R., Waugh, D. W., Lang, C., Rodriguez, J. M., and Nielsen, J. E.: The response of tropical tropospheric ozone to ENSO, Geophys. Res. Lett., 38, L13706, https://doi.org/10.1029/2011gl047865, 2011.
Parrish, D. D., Law, K. S., Staehelin, J., Derwent, R., Cooper, O. R., Tanimoto, H., Volz-Thomas, A., Gilge, S., Scheel, H.-E., Steinbacher, M., and Chan, E.: Long-term changes in lower tropospheric baseline ozone concentrations at northern mid-latitudes, Atmos. Chem. Phys., 12, 11485–11504, https://doi.org/10.5194/acp-12-11485-2012, 2012.
Parrish, D. D., Law, K. S., Staehelin, J., Derwent, R., Cooper, O. R., Tanimoto, H., Volz-Thomas, A., Gilge, S., Scheel, H. E., Steinbacher, M., and Chan, E.: Lower tropospheric ozone at northern midlatitudes: Changing seasonal cycle, Geophys. Res. Lett., 40, 1631–1636, https://doi.org/10.1002/grl.50303, 2013.
Pickering, K. E., Thompson, A. M., Wang, Y., Tao, W.-K., McNamara, D. P., Kirchhoff, V. W. J. H., Heikes, B. G., Sachse, G. W., Bradshaw, J. D., Gregory, G. L., and Blake, D. R.: Convective transport of biomass burning emissions over Brazil during TRACE A, J. Geophys. Res.-Atmos., 101, 23993–24012, https://doi.org/10.1029/96jd00346, 1996.
Randel, W. J. and Cobb, J. B.: Coherent variations of monthly mean total ozone and lower stratospheric temperature, J. Geophys. Res.-Atmos., 99, 5433–5447, https://doi.org/10.1029/93jd03454, 1994.
Randel, W. J. and Thompson, A. M.: Interannual variability and trends in tropical ozone derived from SAGE II satellite data and SHADOZ ozonesondes, J. Geophys. Res.-Atmos., 116, D07303, https://doi.org/10.1029/2010jd015195, 2011.
Randriambelo, T., Baray, J. L., Baldy, S., Bremaud, P., and Cautenet, S.: A case study of extreme tropospheric ozone contamination in the tropics using in-situ, satellite and meteorological data, Geophys. Res. Lett., 26, 1287–1290, https://doi.org/10.1029/1999gl900229, 1999.
Rao, T. N., Kirkwood, S., Arvelius, J., von der Gathen, P., and Kivi, R.: Climatology of UTLS ozone and the ratio of ozone and potential vorticity over northern Europe, J. Geophys. Res.-Atmos., 108, 4703, https://doi.org/10.1029/2003jd003860, 2003.
Rorich, R. P. and Galpin, J. S.: Air quality in the Mpumalanga Highveld region, South Africa, S. Afr. J. Sci., 94, 109–114, 1998.
Schoeberl, M. R., Ziemke, J. R., Bojkov, B., Livesey, N., Duncan, B., Strahan, S., Froidevaux, L., Kulawik, S., Bhartia, P. K., Chandra, S., Levelt, P. F., Witte, J. C., Thompson, A. M., Cuevas, E., Redondas, A., Tarasick, D. W., Davies, J., Bodeker, G., Hansen, G., Johnson, B. J., Oltmans, S. J., Vömel, H., Allaart, M., Kelder, H., Newchurch, M., Godin-Beekmann, S., Ancellet, G., Claude, H., Andersen, S. B., Kyrö, E., Parrondos, M., Yela, M., Zablocki, G., Moore, D., Dier, H., von der Gathen, P., Viatte, P., Stübi, R., Calpini, B., Skrivankova, P., Dorokhov, V., de Backer, H., Schmidlin, F. J., Coetzee, G., Fujiwara, M., Thouret, V., Posny, F., Morris, G., Merrill, J., Leong, C. P., Koenig-Langlo, G., and Joseph, E.: A trajectory-based estimate of the tropospheric ozone column using the residual method, J. Geophys. Res.-Atmos., 112, D24S49, https://doi.org/10.1029/2007jd008773, 2007.
Seidel, D. J., Fu, Q., Randel, W. J., and Reichler, T. J.: Widening of the tropical belt in a changing climate, Nat. Geosci., 1, 21–24, https://doi.org/10.1038/ngeo.2007.38, 2008.
Shindell, D., Faluvegi, G., Lacis, A., Hansen, J., Ruedy, R., and Aguilar, E.: Role of tropospheric ozone increases in 20th-century climate change, J. Geophys. Res.-Atmos., 111, D08302, https://doi.org/10.1029/2005jd006348, 2006.
Sivakumar, V., Bencherif, H., Bègue, N., and Thompson, A. M.: Tropopause Characteristics and Variability from 11 yr of SHADOZ Observations in the Southern Tropics and Subtropics, J. Appl. Meteorol. Clim., 50, 1403–1416, https://doi.org/10.1175/2011jamc2453.1, 2011.
Smit, H. G. J. and Team ASOPOS: Quality assurance and quality control for ozonesonde measurements in GAW, WMO/GAW Rep. 201, 100 pp., Geneva, 2013.
Smit, H. G. J., Straeter, W., Johnson, B. J., Oltmans, S. J., Davies, J., Tarasick, D. W., Hoegger, B., Stubi, R., Schmidlin, F. J., Northam, T., Thompson, A. M., Witte, J. C., Boyd, I., and Posny, F.: Assessment of the performance of ECC-ozonesondes under quasi-flight conditions in the environmental simulation chamber: Insights from the Juelich Ozone Sonde Intercomparison Experiment (JOSIE), J. Geophys. Res.-Atmos., 112, D19306, https://doi.org/10.1029/2006jd007308, 2007.
Smyth, S. B., Sandholm, S. T., Bradshaw, J. D., Talbot, R. W., Blake, D. R., Blake, N. J., Rowland, F. S., Singh, H. B., Gregory, G. L., Anderson, B. E., Sachse, G. W., Collins, J. E., and Bachmeier, A. S.: Factors influencing the upper free tropospheric distribution of reactive nitrogen over the South Atlantic during the TRACE A experiment, J. Geophys. Res.-Atmos., 101, 24165–24186, https://doi.org/10.1029/96jd00224, 1996.
Stajner, I., Wargan, K., Pawson, S., Hayashi, H., Chang, L.-P., Hudman, R. C., Froidevaux, L., Livesey, N., Levelt, P. F., Thompson, A. M., Tarasick, D. W., Stübi, R., Andersen, S. B., Yela, M., König-Langlo, G., Schmidlin, F. J., and Witte, J. C.: Assimilated ozone from EOS-Aura: Evaluation of the tropopause region and tropospheric columns, J. Geophys. Res.-Atmos., 113, D16S32, https://doi.org/10.1029/2007jd008863, 2008.
Stevenson, D. S. Dentener, F. J., Schultz, M. G., Ellingsen, K. van Noije, T. P. C., Wild, O., Zeng, G., Amann, M., Atherton, C. S., Bell, N., Bergmann, D. J., Bey, I., Butler, T., Cofala, J., Collins, W. J., Derwent, R. G., Doherty, R. M., Drevet, J., Eskes, H. J., Fiore, A. M., Gauss, M., Hauglustaine, D. A., Horowitz, L. W., Isaksen, I. S. A., Krol, M. C., Lamarque, J.-F., Lawrence, M. G., Montanaro, V., Müller, J.-F., Pitari, G., Prather, M. J., Pyle, J. A., Rast, S., Rodriguez, J. M., Sanderson, M. G., Savage, N. H., Shindell, D. T., Strahan, S. E., Sudo, K., and Szopa, S.:: Multimodel ensemble simulations of present-day and near-future tropospheric ozone, J. Geophys. Res.-Atmos., 111, D08301, https://doi.org/10.1029/2005jd006338, 2006.
Swap, R., Annegarn, H., Suttles, J., Haywood, J., Helmlinger, M., Hely, C., Hobbs, P., Holben, B., Ji, J., and King, M.: The Southern African Regional Science Initiative (SAFARI 2000): overview of the dry season field campaign, S. Afr. J. Sci., 98, 125–130, 2002.
Swap, R. J., Annegarn, H. J., Suttles, J. T., King, M. D., Platnick, S., Privette, J. L., and Scholes, R. J.: Africa burning: A thematic analysis of the Southern African Regional Science Initiative (SAFARI 2000), J. Geophys. Res.-Atmos., 108, 8465, https://doi.org/10.1029/2003jd003747, 2003.
Thompson, A. M. and Hudson, R. D.: Tropical tropospheric ozone (TTO) maps from Nimbus 7 and Earth Probe TOMS by the modified-residual method: Evaluation with sondes, ENSO signals, and trends from Atlantic regional time series, J. Geophys. Res.-Atmos., 104, 26961–26975, https://doi.org/10.1029/1999jd900470, 1999.
Thompson, A. M., Diab, R. D., Bodeker, G. E., Zunckel, M., Coetzee, G. J. R., Archer, C. B., McNamara, D. P., Pickering, K. E., Combrink, J., Fishman, J., and Nganga, D.: Ozone over southern Africa during SAFARI-92/TRACE A, J. Geophys. Res.-Atmos., 101, 23793–23807, https://doi.org/10.1029/95jd02459, 1996.
Thompson, A. M., Tao, W.-K., Pickering, K. E., Scala, J. R., and Simpson, J.: Tropical deep convection and ozone formation, B. Am. Meteorol. Soc., 78, 1043–1054, 10.1175/1520-0477(1997)078<1043:tdcaof>2.0.co;2, 1997.
Thompson, A. M., Witte, J. C., Hudson, R. D., Guo, H., Herman, J. R., and Fujiwara, M.: Tropical Tropospheric Ozone and Biomass Burning, Science, 291, 2128–2132, https://doi.org/10.1126/science.291.5511.2128, 2001.
Thompson, A. M., Witte, J. C., Freiman, M. T., Phahlane, N. A., and Coetzee, G. J. R.: Lusaka, Zambia, during SAFARI-2000: Convergence of local and imported ozone pollution, Geophys. Res. Lett., 29, 1976, https://doi.org/10.1029/2002gl015399, 2002.
Thompson, A. M., Witte, J. C., McPeters, R. D., Oltmans, S. J., Schmidlin, F. J., Logan, J. A., Fujiwara, M., Kirchhoff, V. W. J. H., Posny, F., Coetzee, G. J. R., Hoegger, B., Kawakami, S., Ogawa, T., Johnson, B. J., Vömel, H., and Labow, G.: Southern Hemisphere Additional Ozonesondes (SHADOZ) 1998–2000 tropical ozone climatology 1. Comparison with Total Ozone Mapping Spectrometer (TOMS) and ground-based measurements, J. Geophys. Res.-Atmos., 108, 8238, https://doi.org/10.1029/2001jd000967, 2003.
Thompson, A. M., Stone, J. B., Witte, J. C., Miller, S. K., Pierce, R. B., Chatfield, R. B., Oltmans, S. J., Cooper, O. R., Loucks, A. L., Taubman, B. F., Johnson, B. J., Joseph, E., Kucsera, T. L., Merrill, J. T., Morris, G. A., Hersey, S., Forbes, G., Newchurch, M. J., Schmidlin, F. J., Tarasick, D. W., Thouret, V., and Cammas, J.-P.: Intercontinental chemical transport experiment ozonesonde network study (IONS) 2004: 1. Summertime upper troposphere/lower stratosphere ozone over northeastern North America, J. Geophys. Res.-Atmos., 112, D12S12, https://doi.org/10.1029/2006JD007441, 2007.
Thompson, A. M., Allen, A. L., Lee, S., Miller, S. K., and Witte, J. C.: Gravity and Rossby wave signatures in the tropical troposphere and lower stratosphere based on Southern Hemisphere Additional Ozonesondes (SHADOZ), 1998–2007, J. Geophys. Res.-Atmos., 116, D05302, https://doi.org/10.1029/2009JD013429, 2011.
Thompson, A. M., Miller, S. K., Tilmes, S., Kollonige, D. W., Witte, J. C., Oltmans, S. J., Johnson, B. J., Fujiwara, M., Schmidlin, F. J., Coetzee, G. J. R., Komala, N., Maata, M., bt Mohamad, M., Nguyo, J., Mutai, C., Ogino, S. Y., Da Silva, F. R., Leme, N. M. P., Posny, F., Scheele, R., Selkirk, H. B., Shiotani, M., Stübi, R., Levrat, G., Calpini, B., Thouret, V., Tsuruta, H., Canossa, J. V., Vömel, H., Yonemura, S., Diaz, J. A., Tan Thanh, N. T., and Thuy Ha, H. T.: Southern Hemisphere Additional Ozonesondes (SHADOZ) ozone climatology (2005–2009): Tropospheric and tropical tropopause layer (TTL) profiles with comparisons to OMI-based ozone products, J. Geophys. Res.-Atmos., 117, D23301, https://doi.org/10.1029/2011jd016911, 2012.
Thouret, V., Marenco, A., Logan, J. A., Nedelec, P., and Grouhel, C.: Comparisons of ozone measurements from the MOZAIC airborne program and the ozone sounding network at eight locations, J. Geophys. Res.-Atmos., 103, 25695–25720, https://doi.org/10.1029/98jd02243, 1998.
Tyson, P. D., Garstang, M., Thompson, A. M., D'Abreton, P., Diab, R. D., and Browell, E. V.: Atmospheric transport and photochemistry of ozone over central Southern Africa during the Southern Africa Fire-Atmosphere Research Initiative, J. Geophys. Res.-Atmos., 102, 10623–10635, https://doi.org/10.1029/97jd00170, 1997.
van der A, R. J., Eskes, H. J., Boersma, K. F., van Noije, T. P. C., Van Roozendael, M., De Smedt, I., Peters, D., and Meijer, E. W.: Trends, seasonal variability and dominant NOx source derived from a ten year record of NO2 measured from space, J. Geophys. Res.-Atmos., 113, D04302, https://doi.org/10.1029/2007jd009021, 2008.
Wilks, D. S.: Resampling Hypothesis Tests for Autocorrelated Fields, J. Climate, 10, 65–82, https://doi.org/10.1175/1520-0442(1997)010<0065:rhtfaf>2.0.co;2, 1997.
Witte, J. C., Schoeberl, M. R., Douglass, A. R., and Thompson, A. M.: The Quasi-biennial Oscillation and annual variations in tropical ozone from SHADOZ and HALOE, Atmos. Chem. Phys., 8, 3929–3936, https://doi.org/10.5194/acp-8-3929-2008, 2008.
Worden, H. M., Deeter, M. N., Edwards, D. P., Gille, J. C., Drummond, J. R., and Nédélec, P.: Observations of near-surface carbon monoxide from space using MOPITT multispectral retrievals, J. Geophys. Res., 115, D18314, https://doi.org/10.1029/2010JD014242, 2010.
Ziemke, J. R., Chandra, S., McPeters, R. D., and Newman, P. A.: Dynamical proxies of column ozone with applications to global trend models, J. Geophys. Res.-Atmos., 102, 6117–6129, https://doi.org/10.1029/96jd03783, 1997.
Zien, A. W., Richter, A., Hilboll, A., Blechschmidt, A.-M., and Burrows, J. P.: Systematic analysis of tropospheric NO2 long-range transport events detected in GOME-2 satellite data, Atmos. Chem. Phys., 14, 7367–7396, https://doi.org/10.5194/acp-14-7367-2014, 2014.
Altmetrics
Final-revised paper
Preprint