Articles | Volume 20, issue 6
https://doi.org/10.5194/acp-20-3945-2020
© Author(s) 2020. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/acp-20-3945-2020
© Author(s) 2020. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
02 Apr 2020
Research article |
| 02 Apr 2020
| 02 Apr 2020
The influence of typhoons on atmospheric composition deduced from IAGOS measurements over Taipei
Frank Roux
CORRESPONDING AUTHOR
Laboratoire d'Aérologie, Université de Toulouse, Centre
National de la Recherche Scientifique, Toulouse, 31400, France
Hannah Clark
IAGOS-AISBL, 98 Rue du Trône, Brussels, 1050, Belgium
Kuo-Ying Wang
Department of Atmospheric Sciences, National Central University,
Taoyuan City, 320, Taiwan
Susanne Rohs
Forschungszentrum Jülich GmbH, Institut für Energie- und
Klimaforschung Troposphäre (IEK-8), 52425 Jülich, Germany
Bastien Sauvage
Laboratoire d'Aérologie, Université de Toulouse, Centre
National de la Recherche Scientifique, Toulouse, 31400, France
Philippe Nédélec
Laboratoire d'Aérologie, Université de Toulouse, Centre
National de la Recherche Scientifique, Toulouse, 31400, France
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Atmos. Chem. Phys., 24, 9975–10000, https://doi.org/10.5194/acp-24-9975-2024, https://doi.org/10.5194/acp-24-9975-2024, 2024
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The study examines tropical tropospheric ozone changes. In situ data from 1994–2019 display increased ozone, notably over India, Southeast Asia, and Malaysia and Indonesia. Sparse in situ data limit trend detection for the 15-year period. In situ and satellite data, with limited sampling, struggle to consistently detect trends. Continuous observations are vital over the tropical Pacific Ocean, Indian Ocean, western Africa, and South Asia for accurate ozone trend estimation in these regions.
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
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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.
Patrick Konjari, Christian Rolf, Michaela Imelda Hegglin, Susanne Rohs, Yun Li, Andreas Zahn, Harald Bönisch, Martina Krämer, and Andreas Petzold
EGUsphere, https://doi.org/10.5194/egusphere-2024-2360, https://doi.org/10.5194/egusphere-2024-2360, 2024
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This study introduces a new method to deriving adjusted water vapor (H2O) climatologies for the upper tropopshere and lower statosphere (UT/LS) using data from 60,000 flights under the IAGOS program. Biases in the IAGOS water vapor dataset are adjusted, based on the more accurate IAGOS-CARIBIC data. The resulting highly resolved H2O climatologies will contribute to a better understanding of the H2O variability in the UT/LS and its connection to various transport and mixing processes.
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
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EGUsphere, https://doi.org/10.5194/egusphere-2024-2012, https://doi.org/10.5194/egusphere-2024-2012, 2024
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Upper tropospheric relative humidity bias in the ERA5 weather model is corrected by 9 % by an artificial neural network using aircraft in-service humidity data and thermodynamic and dynamical variables. The improved skills of the weather model will advance cirrus research, weather forecast and measures for contrail reduction.
Sina Hofer, Klaus Gierens, and Susanne Rohs
Atmos. Chem. Phys., 24, 7911–7925, https://doi.org/10.5194/acp-24-7911-2024, https://doi.org/10.5194/acp-24-7911-2024, 2024
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We try to improve the forecast of ice supersaturation (ISS) and potential persistent contrails using data on dynamical quantities in addition to temperature and relative humidity in a modern kind of regression model. Although the results are improved, they are not good enough for flight routing. The origin of the problem is the strong overlap of probability densities conditioned on cases with and without ice-supersaturated regions (ISSRs) in the important range of 70–100 %.
Roger Teoh, Zebediah Engberg, Ulrich Schumann, Christiane Voigt, Marc Shapiro, Susanne Rohs, and Marc E. J. Stettler
Atmos. Chem. Phys., 24, 6071–6093, https://doi.org/10.5194/acp-24-6071-2024, https://doi.org/10.5194/acp-24-6071-2024, 2024
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The radiative forcing (RF) due to aviation contrails is comparable to that caused by CO2. We estimate that global contrail net RF in 2019 was 62.1 mW m−2. This is ~1/2 the previous best estimate for 2018. Contrail RF varies regionally due to differences in conditions required for persistent contrails. COVID-19 reduced contrail RF by 54% in 2020 relative to 2019. Globally, 2 % of all flights account for 80 % of the annual contrail energy forcing, suggesting a opportunity to mitigate contrail RF.
Sidiki Sanogo, Olivier Boucher, Nicolas Bellouin, Audran Borella, Kevin Wolf, and Susanne Rohs
Atmos. Chem. Phys., 24, 5495–5511, https://doi.org/10.5194/acp-24-5495-2024, https://doi.org/10.5194/acp-24-5495-2024, 2024
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Relative humidity relative to ice (RHi) is a key variable in the formation of cirrus clouds and contrails. This study shows that the properties of the probability density function of RHi differ between the tropics and higher latitudes. In line with RHi and temperature variability, aircraft are likely to produce more contrails with bioethanol and liquid hydrogen as fuel. The impact of this fuel change decreases with decreasing pressure levels but increases from high latitudes to the tropics.
Gerard Ancellet, Camille Viatte, Anne Boynard, François Ravetta, Jacques Pelon, Cristelle Cailteau-Fischbach, Pascal Genau, Julie Capo, Axel Roy, and Philippe Nédélec
EGUsphere, https://doi.org/10.5194/egusphere-2024-892, https://doi.org/10.5194/egusphere-2024-892, 2024
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Characterization of ozone pollution in urban areas has benefited from a measurement campaign in summer 2022 in the Paris region. The analysis is based on 21 days of lidar and aircraft observations. The main objective is a sensitivity analysis of ozone pollution to first the micrometeorological processes in the urban atmospheric boundary layer, and second, the transport of regional pollution. The paper also discuss to what extent satellite observations can track the observed ozone plumes.
Brice Barret, Pierre Loicq, Eric Le Flochmoën, Yasmine Bennouna, Juliette Hadji-Lazaro, Daniel Hurtmans, and Bastien Sauvage
EGUsphere, https://doi.org/10.5194/egusphere-2024-30, https://doi.org/10.5194/egusphere-2024-30, 2024
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Atmospheric profiles of carbon monoxide (CO) retrieved from the IASI spaceborne sensor with the SOFRID and FORLI algorithms are validated against airborne data from the IAGOS Infrastructure for 2008–2020. 8500 daily observations at 33 airports allow a comprehensive spatio-temporal evaluation of the IASI-CO products. They are globally underestimating IAGOS-CO with stronger bias in the mid-upper troposphere south of Bangkok for SOFRID and in the lower troposphere north of Philadelphia for FORLI.
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
EGUsphere, https://doi.org/10.5194/egusphere-2023-2949, https://doi.org/10.5194/egusphere-2023-2949, 2024
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Our study examines intense carbon monoxide (CO) pollution events measured by commercial aircrafts from the 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.
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
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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
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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.
Kevin Wolf, Nicolas Bellouin, Olivier Boucher, Susanne Rohs, and Yun Li
EGUsphere, https://doi.org/10.5194/egusphere-2023-2356, https://doi.org/10.5194/egusphere-2023-2356, 2023
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ERA5 atmospheric reanalysis and airborne in situ observations from IAGOS are compared in terms of representation of the contrail occurrence potential and the presence of supersaturation for persistency. Differences are traced back to biases in ERA5 temperature and, particularly, relative humidity. Those biases are addressed applying a new quantile mapping technique that marginally modifies the contrail representation in ERA5. An overall good statistical contrail representation in ERA5 is found.
Yun Li, Christoph Mahnke, Susanne Rohs, Ulrich Bundke, Nicole Spelten, Georgios Dekoutsidis, Silke Groß, Christiane Voigt, Ulrich Schumann, Andreas Petzold, and Martina Krämer
Atmos. Chem. Phys., 23, 2251–2271, https://doi.org/10.5194/acp-23-2251-2023, https://doi.org/10.5194/acp-23-2251-2023, 2023
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The radiative effect of aviation-induced cirrus is closely related to ambient conditions and its microphysical properties. Our study investigated the occurrence of contrail and natural cirrus measured above central Europe in spring 2014. It finds that contrail cirrus appears frequently in the pressure range 200 to 245 hPa and occurs more often in slightly ice-subsaturated environments than expected. Avoiding slightly ice-subsaturated regions by aviation might help mitigate contrail cirrus.
Clément Narbaud, Jean-Daniel Paris, Sophie Wittig, Antoine Berchet, Marielle Saunois, Philippe Nédélec, Boris D. Belan, Mikhail Y. Arshinov, Sergei B. Belan, Denis Davydov, Alexander Fofonov, and Artem Kozlov
Atmos. Chem. Phys., 23, 2293–2314, https://doi.org/10.5194/acp-23-2293-2023, https://doi.org/10.5194/acp-23-2293-2023, 2023
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We measured CH4 and CO2 from aircraft over the Russian Arctic. Analyzing our data with the Lagrangian model FLEXPART, we find a sharp east–west gradient in atmospheric composition. Western Siberia is influenced by strong wetland CH4 emissions, deep CO2 gradient from biospheric uptake, and long-range transport from Europe and North America. Eastern flights document less variability. Over the Arctic Ocean, we find a small influence from marine CH4 emissions compatible with reasonable inventories.
Antje Inness, Ilse Aben, Melanie Ades, Tobias Borsdorff, Johannes Flemming, Luke Jones, Jochen Landgraf, Bavo Langerock, Philippe Nedelec, Mark Parrington, and Roberto Ribas
Atmos. Chem. Phys., 22, 14355–14376, https://doi.org/10.5194/acp-22-14355-2022, https://doi.org/10.5194/acp-22-14355-2022, 2022
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The Copernicus Atmosphere Monitoring Service (CAMS) provides daily global air quality forecasts to users worldwide. One of the species of interest is carbon monoxide (CO), an important trace gas in the atmosphere with anthropogenic and natural sources, produced by incomplete combustion, for example, by wildfires. This paper looks at how well CAMS can model CO in the atmosphere and shows that the fields can be improved when blending CO data from the TROPOMI instrument with the CAMS model.
Haolin Wang, Xiao Lu, Daniel J. Jacob, Owen R. Cooper, Kai-Lan Chang, Ke Li, Meng Gao, Yiming Liu, Bosi Sheng, Kai Wu, Tongwen Wu, Jie Zhang, Bastien Sauvage, Philippe Nédélec, Romain Blot, and Shaojia Fan
Atmos. Chem. Phys., 22, 13753–13782, https://doi.org/10.5194/acp-22-13753-2022, https://doi.org/10.5194/acp-22-13753-2022, 2022
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We report significant global tropospheric ozone increases in 1995–2017 based on extensive aircraft and ozonesonde observations. Using GEOS-Chem (Goddard Earth Observing System chemistry model) multi-decadal global simulations, we find that changes in global anthropogenic emissions, in particular the rapid increases in aircraft emissions, contribute significantly to the increases in tropospheric ozone and resulting radiative impact.
Boris D. Belan, Gerard Ancellet, Irina S. Andreeva, Pavel N. Antokhin, Viktoria G. Arshinova, Mikhail Y. Arshinov, Yurii S. Balin, Vladimir E. Barsuk, Sergei B. Belan, Dmitry G. Chernov, Denis K. Davydov, Alexander V. Fofonov, Georgii A. Ivlev, Sergei N. Kotel'nikov, Alexander S. Kozlov, Artem V. Kozlov, Katharine Law, Andrey V. Mikhal'chishin, Igor A. Moseikin, Sergei V. Nasonov, Philippe Nédélec, Olesya V. Okhlopkova, Sergei E. Ol'kin, Mikhail V. Panchenko, Jean-Daniel Paris, Iogannes E. Penner, Igor V. Ptashnik, Tatyana M. Rasskazchikova, Irina K. Reznikova, Oleg A. Romanovskii, Alexander S. Safatov, Denis E. Savkin, Denis V. Simonenkov, Tatyana K. Sklyadneva, Gennadii N. Tolmachev, Semyon V. Yakovlev, and Polina N. Zenkova
Atmos. Meas. Tech., 15, 3941–3967, https://doi.org/10.5194/amt-15-3941-2022, https://doi.org/10.5194/amt-15-3941-2022, 2022
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The change of the global climate is most pronounced in the Arctic, where the air temperature increases faster than the global average. This is associated with an increase in the concentration of greenhouse gases in the atmosphere. It is important to study how the air composition in the Arctic changes in the changing climate. Thus this integrated experiment was carried out to measure the composition of the troposphere in the Russian sector of the Arctic from on board the aircraft laboratory.
Klaus Gierens, Lena Wilhelm, Sina Hofer, and Susanne Rohs
Atmos. Chem. Phys., 22, 7699–7712, https://doi.org/10.5194/acp-22-7699-2022, https://doi.org/10.5194/acp-22-7699-2022, 2022
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We are interested in the prediction of condensation trails, in particular strong ones. For this we need a good forecast of temperature and humidity in the levels where aircraft cruise. Unfortunately, the humidity forecast is quite difficult for these levels, in particular the ice supersaturation, which is needed for long-lasting contrails. We are thus seeking proxy variables that help distinguish situations where strong contrails can form, for instance the lapse rate.
Dimitris Akritidis, Andrea Pozzer, Johannes Flemming, Antje Inness, Philippe Nédélec, and Prodromos Zanis
Atmos. Chem. Phys., 22, 6275–6289, https://doi.org/10.5194/acp-22-6275-2022, https://doi.org/10.5194/acp-22-6275-2022, 2022
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We perform a process-oriented evaluation of Copernicus Atmosphere Monitoring Service (CAMS) reanalysis (CAMSRA) O3 over Europe using WOUDC (World Ozone and Ultraviolet Radiation Data Centre) ozonesondes and IAGOS (In-service Aircraft for a Global Observing System) aircraft measurements. Chemical data assimilation assists CAMSRA to reproduce the observed O3 increases in the troposphere during the examined folding events, but it mostly results in O3 overestimation in the upper troposphere.
Graciela B. Raga, Darrel Baumgardner, Blanca Rios, Yanet Díaz-Esteban, Alejandro Jaramillo, Martin Gallagher, Bastien Sauvage, Pawel Wolff, and Gary Lloyd
Atmos. Chem. Phys., 22, 2269–2292, https://doi.org/10.5194/acp-22-2269-2022, https://doi.org/10.5194/acp-22-2269-2022, 2022
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The In-Service Aircraft for a Global Observing System (IAGOS) is a small fleet of commercial aircraft that carry a suite of meteorological, gas, aerosol, and cloud sensors and have been measuring worldwide for almost 9 years, since late 2011. Extreme ice events (EIEs) have been identified from the IAGOS cloud measurements and linked to surface emissions for biomass and fossil fuel consumption. The results reported here are highly relevant for climate change and flight operations forecasting.
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
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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.
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
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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.
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
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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.
Keun-Ok Lee, Brice Barret, Eric L. Flochmoën, Pierre Tulet, Silvia Bucci, Marc von Hobe, Corinna Kloss, Bernard Legras, Maud Leriche, Bastien Sauvage, Fabrizio Ravegnani, and Alexey Ulanovsky
Atmos. Chem. Phys., 21, 3255–3274, https://doi.org/10.5194/acp-21-3255-2021, https://doi.org/10.5194/acp-21-3255-2021, 2021
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This paper focuses on the emission sources and pathways of pollution from the boundary layer to the Asian monsoon anticyclone (AMA) during the StratoClim aircraft campaign period. Simulations with the Meso-NH cloud-chemistry model at a horizontal resolution of 15 km are performed over the Asian region to characterize the impact of monsoon deep convection on the composition of AMA and on the formation of the Asian tropopause aerosol layer during the StratoClim campaign.
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
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
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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.
Andreas Petzold, Patrick Neis, Mihal Rütimann, Susanne Rohs, Florian Berkes, Herman G. J. Smit, Martina Krämer, Nicole Spelten, Peter Spichtinger, Philippe Nédélec, and Andreas Wahner
Atmos. Chem. Phys., 20, 8157–8179, https://doi.org/10.5194/acp-20-8157-2020, https://doi.org/10.5194/acp-20-8157-2020, 2020
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The first analysis of 15 years of global-scale water vapour and relative humidity observations by passenger aircraft in the MOZAIC and IAGOS programmes resolves detailed features of water vapour and ice-supersaturated air in the mid-latitude tropopause. Key results provide in-depth insight into seasonal and regional variability and chemical signatures of ice-supersaturated air masses, including trend analyses, and show a close link to cirrus clouds and their highly important effects on climate.
Philipp Reutter, Patrick Neis, Susanne Rohs, and Bastien Sauvage
Atmos. Chem. Phys., 20, 787–804, https://doi.org/10.5194/acp-20-787-2020, https://doi.org/10.5194/acp-20-787-2020, 2020
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This study compares in situ measurements of temperature and humidity in the upper troposphere and lower stratosphere with reanalysis data from the ECMWF ERA-Interim data set. It is shown that temperature compares well between both data sets. However, extreme values of relative humidity with respect to ice (RHi) are missing in ERA-Interim, and hence the number and size of ice supersaturated regions differ strongly between both data sets.
Kuo-Ying Wang, Philippe Nedelec, Hannah Clark, and Neil Harris
Earth Syst. Sci. Data Discuss., https://doi.org/10.5194/essd-2019-156, https://doi.org/10.5194/essd-2019-156, 2019
Revised manuscript not accepted
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Atmospheric dispersion of radioactive materials following the accidents of the 11 March 2011 Fukushima Nuclear Power Plants contain very distinctive characteristics
over the land surface areas and over the oceanic atmosphere. Air dose rates measured over the land surface areas exhibit a combination of the effects from the deposited radioactive materials on the surface and the airborne radioactive materials. Air dose rates measured over the oceanic atmosphere were due to airborne particles.
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
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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.
Dimitris Akritidis, Eleni Katragkou, Prodromos Zanis, Ioannis Pytharoulis, Dimitris Melas, Johannes Flemming, Antje Inness, Hannah Clark, Matthieu Plu, and Henk Eskes
Atmos. Chem. Phys., 18, 15515–15534, https://doi.org/10.5194/acp-18-15515-2018, https://doi.org/10.5194/acp-18-15515-2018, 2018
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Analysis and evaluation of the Copernicus Atmosphere Monitoring Service (CAMS) global and regional forecast systems during a deep stratosphere-to-troposphere ozone transport event over Europe in January 2017. Radiosondes, satellite images, ozonesondes and aircraft measurements were used to investigate the folding of the tropopause at several European sites and the induced presence of dry and ozone-rich air in the troposphere.
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
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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.
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
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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.
Bastien Sauvage, Alain Fontaine, Sabine Eckhardt, Antoine Auby, Damien Boulanger, Hervé Petetin, Ronan Paugam, Gilles Athier, Jean-Marc Cousin, Sabine Darras, Philippe Nédélec, Andreas Stohl, Solène Turquety, Jean-Pierre Cammas, and Valérie Thouret
Atmos. Chem. Phys., 17, 15271–15292, https://doi.org/10.5194/acp-17-15271-2017, https://doi.org/10.5194/acp-17-15271-2017, 2017
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We provide the scientific community with a SOFT-IO tool based on the coupling of Lagrangian modeling with emission inventories and aircraft CO measurements, which is able to calculate the contribution of the sources and geographical origins of CO measurements, with good performances. Calculated CO added-value products will help scientists in interpreting large IAGOS CO data set. SOFT-IO could further be applied to other CO data sets or used to help validate emission inventories.
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
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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.
Marine Claeys, Greg Roberts, Marc Mallet, Jovanna Arndt, Karine Sellegri, Jean Sciare, John Wenger, and Bastien Sauvage
Atmos. Chem. Phys., 17, 7891–7915, https://doi.org/10.5194/acp-17-7891-2017, https://doi.org/10.5194/acp-17-7891-2017, 2017
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Over a period of 5 days (summer 2013), the mass concentration of primary marine aerosols was dominant compared to other aerosols measured at a ground-based measuring site on Corsica. The characteristics of primary marine aerosols such as their size distribution, their optical properties and their direct radiative effect were studied as a function of their ageing and region of emission. These characteristics were compared to two other periods dominated by different aerosol regimes.
Tobias Borsdorff, Joost aan de Brugh, Haili Hu, Philippe Nédélec, Ilse Aben, and Jochen Landgraf
Atmos. Meas. Tech., 10, 1769–1782, https://doi.org/10.5194/amt-10-1769-2017, https://doi.org/10.5194/amt-10-1769-2017, 2017
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
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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.
Brice Barret, Bastien Sauvage, Yasmine Bennouna, and Eric Le Flochmoen
Atmos. Chem. Phys., 16, 9129–9147, https://doi.org/10.5194/acp-16-9129-2016, https://doi.org/10.5194/acp-16-9129-2016, 2016
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During the Asian Monsoon, pollutants are uplifted to the upper troposphere where they are trapped within the large scale Asian monsoon anticyclone. Among these pollutants are O3 precursors such as nitrogen oxides (NOx) and carbon monoxide (CO). Based on satellite observations and model simulations, we have estimated the impact of anthropogenic and natural sources on O3 in the monsoon anticyclone. Our results show that Asian pollution and LiNOx have comparable contributions.
Alicia Gressent, Bastien Sauvage, Daniel Cariolle, Mathew Evans, Maud Leriche, Céline Mari, and Valérie Thouret
Atmos. Chem. Phys., 16, 5867–5889, https://doi.org/10.5194/acp-16-5867-2016, https://doi.org/10.5194/acp-16-5867-2016, 2016
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In chemical transport models, NOx emitted by lightning (LNOx) is instantaneously diluted into the grid. A plume-in-grid parameterization to account for the sub-grid chemistry of LNOx is presented. This approach was implemented into the GEOS-Chem model and leads to a relative increase of NOx and O3 (18 % and 2 %, respectively, in July) on a large scale downwind of lightning emissions and a relative decrease (25 % and 8 %, respectively, over central Africa in July) over the regions of emissions.
Xuewu Fu, Nicolas Marusczak, Lars-Eric Heimbürger, Bastien Sauvage, François Gheusi, Eric M. Prestbo, and Jeroen E. Sonke
Atmos. Chem. Phys., 16, 5623–5639, https://doi.org/10.5194/acp-16-5623-2016, https://doi.org/10.5194/acp-16-5623-2016, 2016
J. Meyer, C. Rolf, C. Schiller, S. Rohs, N. Spelten, A. Afchine, M. Zöger, N. Sitnikov, T. D. Thornberry, A. W. Rollins, Z. Bozóki, D. Tátrai, V. Ebert, B. Kühnreich, P. Mackrodt, O. Möhler, H. Saathoff, K. H. Rosenlof, and M. Krämer
Atmos. Chem. Phys., 15, 8521–8538, https://doi.org/10.5194/acp-15-8521-2015, https://doi.org/10.5194/acp-15-8521-2015, 2015
J.-F. Léon, P. Augustin, M. Mallet, T. Bourrianne, V. Pont, F. Dulac, M. Fourmentin, D. Lambert, and B. Sauvage
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acpd-15-9507-2015, https://doi.org/10.5194/acpd-15-9507-2015, 2015
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This paper presents the aerosol vertical distribution observed by lidar soundings in Corsica (western Mediterranean) between February 2012 and August 2013. A seasonal cycle is observed in the extinction coefficient profiles and aerosol optical thickness with minima in winter and maxima in spring-summer. Less than 10% of the daily observations show high AOD corresponding to the large-scale advection of desert dust from Northern Africa or pollution aerosols from Europe.
H. G. J. Smit, S. Rohs, P. Neis, D. Boulanger, M. Krämer, A. Wahner, and A. Petzold
Atmos. Chem. Phys., 14, 13241–13255, https://doi.org/10.5194/acp-14-13241-2014, https://doi.org/10.5194/acp-14-13241-2014, 2014
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Long-term water vapour measurements from the MOZAIC programme are a unique source for upper troposphere humidity data. However, due to an error in the calibration procedure, RH data from MOZAIC were biased towards higher values for the period starting in year 2000. Here we report the procedures followed to reanalyse the calibrations and to reprocess the entire MOZAIC RH data. This study serves as the reference publication for the reanalysed MOZAIC RH data base for the period 1994 to 2009.
O. Stein, M. G. Schultz, I. Bouarar, H. Clark, V. Huijnen, A. Gaudel, M. George, and C. Clerbaux
Atmos. Chem. Phys., 14, 9295–9316, https://doi.org/10.5194/acp-14-9295-2014, https://doi.org/10.5194/acp-14-9295-2014, 2014
G. Wetzel, H. Oelhaf, G. Berthet, A. Bracher, C. Cornacchia, D. G. Feist, H. Fischer, A. Fix, M. Iarlori, A. Kleinert, A. Lengel, M. Milz, L. Mona, S. C. Müller, J. Ovarlez, G. Pappalardo, C. Piccolo, P. Raspollini, J.-B. Renard, V. Rizi, S. Rohs, C. Schiller, G. Stiller, M. Weber, and G. Zhang
Atmos. Chem. Phys., 13, 5791–5811, https://doi.org/10.5194/acp-13-5791-2013, https://doi.org/10.5194/acp-13-5791-2013, 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: Dynamics | Research Activity: Atmospheric Modelling and Data Analysis | Altitude Range: Troposphere | Science Focus: Chemistry (chemical composition and reactions)
Seasonal characteristics of atmospheric peroxyacetyl nitrate (PAN) in a coastal city of Southeast China: Explanatory factors and photochemical effects
Atmospheric oxidation capacity and ozone pollution mechanism in a coastal city of southeastern China: analysis of a typical photochemical episode by an observation-based model
Error induced by neglecting subgrid chemical segregation due to inefficient turbulent mixing in regional chemical-transport models in urban environments
Statistical regularization for trend detection: an integrated approach for detecting long-term trends from sparse tropospheric ozone profiles
Description and Evaluation of the specified-dynamics experiment in the Chemistry-Climate Model Initiative
Large-scale transport into the Arctic: the roles of the midlatitude jet and the Hadley Cell
Large-scale tropospheric transport in the Chemistry–Climate Model Initiative (CCMI) simulations
Multi-model study of mercury dispersion in the atmosphere: vertical and interhemispheric distribution of mercury species
CFD modeling of reactive pollutant dispersion in simplified urban configurations with different chemical mechanisms
Forty years of improvements in European air quality: regional policy-industry interactions with global impacts
Simulations of a cold-air pool associated with elevated wintertime ozone in the Uintah Basin, Utah
Tropical convective transport and the Walker circulation
Transport of short-lived species into the Tropical Tropopause Layer
Nudging technique for scale bridging in air quality/climate atmospheric composition modelling
On the segregation of chemical species in a clear boundary layer over heterogeneous land surfaces
SOSA – a new model to simulate the concentrations of organic vapours and sulphuric acid inside the ABL – Part 1: Model description and initial evaluation
Taotao Liu, Gaojie Chen, Jinsheng Chen, Lingling Xu, Mengren Li, Youwei Hong, Yanting Chen, Xiaoting Ji, Chen Yang, Yuping Chen, Weiguo Huang, Quanjia Huang, and Hong Wang
Atmos. Chem. Phys., 22, 4339–4353, https://doi.org/10.5194/acp-22-4339-2022, https://doi.org/10.5194/acp-22-4339-2022, 2022
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We clarified the seasonal variations of PAN pollution, influencing factors, its mechanisms, and impacts on O3 based on OBM and GAM models. PAN presented inhibition and promotion effects on O3 under low and high ROx levels. Monitoring of PAN and its precursors, and the quantification of its impacts on O3 formation, significantly guide photochemical pollution control. The analysis methods used in this study provide a reference for study of the formation mechanisms of PAN and O3 in other regions.
Taotao Liu, Youwei Hong, Mengren Li, Lingling Xu, Jinsheng Chen, Yahui Bian, Chen Yang, Yangbin Dan, Yingnan Zhang, Likun Xue, Min Zhao, Zhi Huang, and Hong Wang
Atmos. Chem. Phys., 22, 2173–2190, https://doi.org/10.5194/acp-22-2173-2022, https://doi.org/10.5194/acp-22-2173-2022, 2022
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Based on the OBM-MCM model analyses, the study aims to clarify (1) the pollution characteristics of O3 and its precursors, (2) the atmospheric oxidation capacity and radical chemistry, and (3) the O3 formation mechanism and sensitivity analysis. The results are expected to enhance the understanding of the O3 formation mechanism with low O3 precursor levels and provide scientific evidence for O3 pollution control in coastal cities.
Cathy W. Y. Li, Guy P. Brasseur, Hauke Schmidt, and Juan Pedro Mellado
Atmos. Chem. Phys., 21, 483–503, https://doi.org/10.5194/acp-21-483-2021, https://doi.org/10.5194/acp-21-483-2021, 2021
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Intense and localised emissions of pollutants are common in urban environments, in which turbulence cannot mix these segregated pollutants efficiently in the atmosphere. Despite their relatively high resolution, regional models cannot resolve such segregation and assume instantaneous mixing of these pollutants in their model grids, which potentially induces significant error in the subsequent chemical calculation, based on our calculation with a model that explicitly resolves turbulent motions.
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
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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.
Clara Orbe, David A. Plummer, Darryn W. Waugh, Huang Yang, Patrick Jöckel, Douglas E. Kinnison, Beatrice Josse, Virginie Marecal, Makoto Deushi, Nathan Luke Abraham, Alexander T. Archibald, Martyn P. Chipperfield, Sandip Dhomse, Wuhu Feng, and Slimane Bekki
Atmos. Chem. Phys., 20, 3809–3840, https://doi.org/10.5194/acp-20-3809-2020, https://doi.org/10.5194/acp-20-3809-2020, 2020
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Atmospheric composition is strongly influenced by global-scale winds that are not always properly simulated in computer models. A common approach to correct for this bias is to relax or
nudgeto the observed winds. Here we systematically evaluate how well this technique performs across a large suite of chemistry–climate models in terms of its ability to reproduce key aspects of both the tropospheric and stratospheric circulations.
Huang Yang, Darryn W. Waugh, Clara Orbe, Guang Zeng, Olaf Morgenstern, Douglas E. Kinnison, Jean-Francois Lamarque, Simone Tilmes, David A. Plummer, Patrick Jöckel, Susan E. Strahan, Kane A. Stone, and Robyn Schofield
Atmos. Chem. Phys., 19, 5511–5528, https://doi.org/10.5194/acp-19-5511-2019, https://doi.org/10.5194/acp-19-5511-2019, 2019
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We evaluate the performance of a suite of models in simulating the large-scale transport from the northern midlatitudes to the Arctic using a CO-like idealized tracer. We find a large multi-model spread of the Arctic concentration of this CO-like tracer that is well correlated with the differences in the location of the midlatitude jet as well as the northern Hadley Cell edge. Our results suggest the Hadley Cell is key and zonal-mean transport by surface meridional flow needs better constraint.
Clara Orbe, Huang Yang, Darryn W. Waugh, Guang Zeng, Olaf Morgenstern, Douglas E. Kinnison, Jean-Francois Lamarque, Simone Tilmes, David A. Plummer, John F. Scinocca, Beatrice Josse, Virginie Marecal, Patrick Jöckel, Luke D. Oman, Susan E. Strahan, Makoto Deushi, Taichu Y. Tanaka, Kohei Yoshida, Hideharu Akiyoshi, Yousuke Yamashita, Andreas Stenke, Laura Revell, Timofei Sukhodolov, Eugene Rozanov, Giovanni Pitari, Daniele Visioni, Kane A. Stone, Robyn Schofield, and Antara Banerjee
Atmos. Chem. Phys., 18, 7217–7235, https://doi.org/10.5194/acp-18-7217-2018, https://doi.org/10.5194/acp-18-7217-2018, 2018
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In this study we compare a few atmospheric transport properties among several numerical models that are used to study the influence of atmospheric chemistry on climate. We show that there are large differences among models in terms of the timescales that connect the Northern Hemisphere midlatitudes, where greenhouse gases and ozone-depleting substances are emitted, to the Southern Hemisphere. Our results may have important implications for how models represent atmospheric composition.
Johannes Bieser, Franz Slemr, Jesse Ambrose, Carl Brenninkmeijer, Steve Brooks, Ashu Dastoor, Francesco DeSimone, Ralf Ebinghaus, Christian N. Gencarelli, Beate Geyer, Lynne E. Gratz, Ian M. Hedgecock, Daniel Jaffe, Paul Kelley, Che-Jen Lin, Lyatt Jaegle, Volker Matthias, Andrei Ryjkov, Noelle E. Selin, Shaojie Song, Oleg Travnikov, Andreas Weigelt, Winston Luke, Xinrong Ren, Andreas Zahn, Xin Yang, Yun Zhu, and Nicola Pirrone
Atmos. Chem. Phys., 17, 6925–6955, https://doi.org/10.5194/acp-17-6925-2017, https://doi.org/10.5194/acp-17-6925-2017, 2017
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We conducted a multi model study to investigate our ability to reproduce the vertical distribution of mercury in the atmosphere. For this, we used observational data from over 40 aircraft flights in EU and US. We compared observations to the results of seven chemistry transport models and found that the models are able to reproduce vertical gradients of total and elemental Hg. Finally, we found that different chemical reactions seem responsible for the oxidation of Hg depending on altitude.
Beatriz Sanchez, Jose-Luis Santiago, Alberto Martilli, Magdalena Palacios, and Frank Kirchner
Atmos. Chem. Phys., 16, 12143–12157, https://doi.org/10.5194/acp-16-12143-2016, https://doi.org/10.5194/acp-16-12143-2016, 2016
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This paper is focused on analyzing the coupled behavior between dispersion of reactive pollutants and atmospheric dynamics in different atmospheric conditions using a computational fluid dynamics model. It allows one to provide the selection of the chemical reactions needed that gives the best compromise between accuracy in modeling NO and NO2 dispersion in the streets and the computational time required. The conclusions can be applied to future studies about modeling air quality in cities.
Monica Crippa, Greet Janssens-Maenhout, Frank Dentener, Diego Guizzardi, Katerina Sindelarova, Marilena Muntean, Rita Van Dingenen, and Claire Granier
Atmos. Chem. Phys., 16, 3825–3841, https://doi.org/10.5194/acp-16-3825-2016, https://doi.org/10.5194/acp-16-3825-2016, 2016
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The interplay of European air quality policies and technological advancement to reduce anthropogenic emissions avoided a dramatic deterioration of air quality in Europe and beyond over the last 40 years (e.g. fuel quality directives reduced global SO2 emissions by 88 %, while the EURO standards led to a 50 % reduction of PM2.5). The story told by the EDGAR retrospective scenarios can be informative for designing multi-pollutant abatement policies also in emerging economies.
E. M. Neemann, E. T. Crosman, J. D. Horel, and L. Avey
Atmos. Chem. Phys., 15, 135–151, https://doi.org/10.5194/acp-15-135-2015, https://doi.org/10.5194/acp-15-135-2015, 2015
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This paper uses numerical model simulations to investigate the meteorological characteristics of the 31 January–6 February 2013 cold-air pool (also know as a temperature 'inversion') in the Uintah Basin, Utah, and the resulting high ozone concentrations. A number of factors that influence cold pools and pollutant concentrations in the Uintah Basin are discussed, including snow cover, ice fog, and thermally driven flows.
J. S. Hosking, M. R. Russo, P. Braesicke, and J. A. Pyle
Atmos. Chem. Phys., 12, 9791–9797, https://doi.org/10.5194/acp-12-9791-2012, https://doi.org/10.5194/acp-12-9791-2012, 2012
M. J. Ashfold, N. R. P. Harris, E. L. Atlas, A. J. Manning, and J. A. Pyle
Atmos. Chem. Phys., 12, 6309–6322, https://doi.org/10.5194/acp-12-6309-2012, https://doi.org/10.5194/acp-12-6309-2012, 2012
A. Maurizi, F. Russo, M. D'Isidoro, and F. Tampieri
Atmos. Chem. Phys., 12, 3677–3685, https://doi.org/10.5194/acp-12-3677-2012, https://doi.org/10.5194/acp-12-3677-2012, 2012
H. G. Ouwersloot, J. Vilà-Guerau de Arellano, C. C. van Heerwaarden, L. N. Ganzeveld, M. C. Krol, and J. Lelieveld
Atmos. Chem. Phys., 11, 10681–10704, https://doi.org/10.5194/acp-11-10681-2011, https://doi.org/10.5194/acp-11-10681-2011, 2011
M. Boy, A. Sogachev, J. Lauros, L. Zhou, A. Guenther, and S. Smolander
Atmos. Chem. Phys., 11, 43–51, https://doi.org/10.5194/acp-11-43-2011, https://doi.org/10.5194/acp-11-43-2011, 2011
Cited articles
Akritidis, D., Katragkou, E., Zanis, P., Pytharoulis, I., Melas, D.,
Flemming, J., Inness, A., Clark, H., Plu, M., and Eskes, H.: A deep
stratosphere-to-troposphere ozone transport event over Europe simulated in
CAMS global and regional forecast systems: analysis and evaluation, Atmos.
Chem. Phys., 18, 15515–15534, https://doi.org/10.5194/acp-18-15515-2018, 2018.
Baray, J.-L., Ancellet, G., Randriambelo, T., and Baldy, S.: Tropical
cyclone Marlene and Stratosphere-Troposphere Exchange, J. Geophys. Res.,
104, 13953–13970, https://doi.org/10.1029/1999JD900028, 1999.
Barthe, C., Hoarau, T., and Bovalo, C.: Cloud electrification and lightning
activity in a tropical cyclone-like vortex, Atmos. Res., 180, 297–309,
https://doi.org/10.1016/j.atmosres.2016.05.023, 2016.
Berkes, F., Houben, N., Bundke, U., Franke, H., Pätz, H.-W., Rohrer, F.,
Wahner, A., and Petzold, A.: The IAGOS NOx instrument – design,
operation and first results from deployment aboard passenger aircraft,
Atmos. Meas. Tech., 11, 3737–3757, https://doi.org/10.5194/amt-11-3737-2018, 2018.
Brioude, J., Cammas, J.-P., and Cooper, O. R.: Stratosphere-troposphere
exchange in a summertime extratropical low: Analysis, Atmos. Chem. Phys.,
6, 2337–2353, https://doi.org/10.5194/acp-6-2337-2006, 2006.
Cairo, F., Buontempo, C., MacKenzie, A. R., Schiller, C., Volk, C. M., Adriani, A., Mitev, V., Matthey, R., Di Donfrancesco, G., Oulanovsky, A., Ravegnani, F., Yushkov, V., Snels, M., Cagnazzo, C., and Stefanutti, L.: Morphology of the tropopause layer and lower stratosphere above a tropical cyclone: a case study on cyclone Davina (1999), Atmos. Chem. Phys., 8, 3411–3426, https://doi.org/10.5194/acp-8-3411-2008, 2008.
Chen, Y.-H., Kuo, H.-C., Wang, C.-C., and Yi-Ting Yang, Y.-T.: Influence
of southwest monsoon flow and typhoon track on Taiwan rainfall during the
exit phase: modelling study of typhoon Morakot (2009), Q. J. Roy. Meteor.
Soc., 143, 3014–3024, https://doi.org/10.1002/qj.3156, 2015.
Chow, E. C. H., Li, R. C. Y., and Zhou, W.: Influence of tropical cyclones on
Hong Kong air quality, Adv. Atmos. Sci., 35, 1177–1188, https://doi.org/10.1007/S00376-018-7225-4, 2018.
Clark, H. L., Sauvage, B., Thouret, V., Nédélec, P., Blot, R., Wang, K.-Y., Smit, H., Neis, P., Petzold, A., Athier, G. , Boulanger, D., Cousin, J.-M., Beswick, K., Gallagher, M., Baumgardner, D., Kaiser, J., Flaud, J.-M., Wahner, A., Volz-Thomas, A., and Cammas, J.-P.:
The first regular measurements of ozone, carbon monoxide and water vapour in
the Pacific UTLS by IAGOS, Tellus B, 67, 28385,
https://doi.org/10.3402/tellusb.v67.28385, 2015.
Clark, H., Petzold, A., Thouret, V., and Zahn, A.: IAGOS data, available at: http://www.iagos-data.fr, last access: 31 March 2020.
Das, S. S.: A new perspective on MST radar observation of stratospheric
intrusions into troposphere associated with tropical cyclone, Geophys.
Res. Lett., 36, L15821, https://doi.org/10.1029/2009GL039184, 2009.
Das, S. S., Sijikumar, S., and Uma, K. N.: Further investigation on
stratospheric air intrusion into the troposphere during the episode of
tropical cyclone: Numerical simulation and MST radar observations, Atmos.
Res., 101, 928–937, https://doi.org/10.1016/j.atmosres.2011.05.023, 2011.
Das, S. S., Ratnam, M. K., Uma, K. N., Subrahmanyam, K. V., Girach, I. A., Patra,
A. K., Aneesh, S., Suneeth, K. V., Kumar, K. K., Kesarkar, A. P., Sijikumar, S.,
and Ramkumar, G.: Influence of tropical cyclones on tropospheric ozone:Possible implications, Atmos. Chem. Phys., 16, 4837–4847, https://doi.org/10.5194/acp-16-4837-2016, 2016.
Dauhut, T., Chaboureau, J., Haynes, P. H., and Lane, T. P.: The Mechanisms
leading to a stratospheric hydration by overshooting convection, J. Atmos.
Sci., 75, 4383–4398, https://doi.org/10.1175/JAS-D-18-0176.1, 2018.
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., Kâllberg, Köhler, M., Matricardi, M., McNally, A. P., Monge-Sanz, B. M., Morcrette, J.-J., Park, B.-K., Peubey, C., de Rosnay, P., Tavolato, C., Thépaut, 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.
De Forster, P. M. F. and Shine, K. P.: Radiative forcing and temperature
trends from stratospheric ozone changes, J. Geophys. Res., 102,
10841–10855, https://doi.org/10.1029/96JD03510, 1997.
DeMaria, M., DeMaria, R. T., Knaff, J. A., and Molenar, D.: Tropical
cyclone lightning and rapid intensity change, Month. Weather Rev., 140,
1828–1842, https://doi.org/10.1175/MWR-D-11-00236.1, 2012.
Feng, Y., Wang, A., Wu, D., and Xu, X.: The influence of tropical cyclone
Melor on PM10 concentrations during an aerosol episode over the Pearl
River Delta region of China:Numerical modeling versus observational
analysis, Atmos. Environ., 41, 4349–4365, 2007.
Fierro, A. O. and Reisner, J. M.: High-resolution simulation of the
electrification and lightning of Hurricane Rita during the period of rapid
intensification, J. Atmos. Sci., 68, 477–494, https://doi.org/10.1175/2010JAS3659.1, 2011.
Gettelman, A., de Forster, P. M. F., Fujiwara, M., Fu, Q., Vömel, H.,
Gohar, L. K., Johanson, C., and Ammerman, M.: Radiation balance of the
tropical tropopause layer, J. Geophys. Res., 109, D07103, https://doi.org/10.1029/2003JD004190, 2004.
Gettelman, A., Hoor, P., Pan, L. L., Randel, W. J., Hegglin, M. I., and
Birner, T.: The extratropical upper troposphere and lower stratosphere,
Rev. Geophys., 49, RG3003, https://doi.org/10.1029/2011RG000355, 2011.
Gibbins, C. J.: A survey and comparison of relationships for the
determination of the saturation vapor pressure over plane surfaces of pure
water and of pure ice, Ann. Geophys., 8, 859–886, 1990.
Goff, J. A. and Gratch, S.: Low pressure properties of water from −160 to
+212 F, Transactions of the 52nd Annual Meeting of the American
Society of Heating and Ventilating Engineers, Murray bay, Québec,
Canada, 95–102, 1946.
Hegglin, M. I., Boone, C. D., Manney, G. L., and Walker, K. A.: A global
view of the extratropical tropopause transition layer from Atmospheric
Chemistry Experiment Fourier Transform Spectrometer O3, H2O, and CO, J.
Geophys. Res., 114, D00B11, https://doi.org/10.1029/2008JD009984, 2009.
Hersbach, H. and Dee, D.: ERA-5 reanalysis is in production, ECMWF
Newsletter, 147, 7 pp., 2016.
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.
Hoor, P., Fischer, H., Lange, L., and Lelieveld, J.: Seasonal variations
of a mixing layer in the lowermost stratosphere as identified by the CO-O3
correlation from in situ measurements, J. Geophys. Res, 107, 4044, https://doi.org/10.1029/2000JD000289, 2002.
Huang, J.-P., Fung, J. C. H., Lau, A. K. H., and Qin, Y.: Numerical
simulations and process analysis of typhoon-related ozone episodes in Hong
Kong, J. Geophys. Res., 110, D05301, https://doi.org/10.1029/2004JD004914, 2005.
Hung, C.-H. and Lo, K.-C.: Relationship between ambient ozone
concentration changes in southwestern Taiwan and invasion tracks of tropical
typhoons, Adv. Meteorol., 2015, 402976, https://doi.org/10.1155/2015/402976, 2015.
Instiitut Pierre Simon Laplace IPSL. Laboratoire de Météorologie Dynamique: ERA-5 data, available at: http://climserv.ipsl.polytechnique.fr/, last access: 31 March 2020.
Jenkins, G. J., Robjhon, M. L., Reyes, A., Valentine, A., and Neves, L.: Elevated middle and upper troposphere ozone observed downstream of
Atlantic tropical cyclones, Atmos. Environ., 118, 78–86, 2015.
Jiang, Y. C., Zhao, T. L., Liu, J., Xu, X. D., Tan, C. H., Cheng, X. H., Bi,
X. Y., Gan, J. B., You, J. F., and Zhao, S. Z.: Why does surface ozone peak
before a typhoon landing in southeast China, Atmos. Chem. Phys., 15,
13331–13338, https://doi.org/10.5194/acp-15-13331-2015, 2015.
JTWC Guam: Annual Tropical Cyclone Report 2016, Joint Typhoon Warning
Center, United States Air Force and United States Navy, available at: http://www.metoc.navy.mil/jtwc/products/atcr/2016atcr.pdf (last access: 31 March 2020), 2017.
Lafore, J.-P., Stein, J., Asencio, N., Bougeault, P., Ducrocq, V., Duron,
J., Fischer, C., Héreil, P., Mascart, P., Masson, V., Pinty, J.-P.,
Redelsperger, J.-L., Richard, E., and Vilà-Guerau de Arellano, J.:
The Meso-NH Atmospheric Simulation System, Part I: adiabatic formulation
and control simulations. Scientific objectives and experimental design,
Ann. Geophys., 16, 90–109, https://doi.org/10.1007/s00585-997-0090-6, 1998.
Leclair de Bellevue, J., Baray, J.-L., Baldy, S., Ancellet, G., Diab, R.,
and Ravetta, F.: Simulation of stratosphere to troposphere transport
during the tropical cyclone Marlene event, Atmos. Environ., 41, 6510–6526,
https://doi.org/10.1016/j.atmosenv.2007.04.040, 2007.
Lee, Y. C., Calori, G., Hills, P., and Carmichael, G. R.: Ozone episodes in
urban Hong Kong 1994–1999, Atmos. Environ., 36, 1957–1968, https://doi.org/10.1016/S1352-2310(02)00150-4, 2002.
Lelieveld, J. and Crutzen, P. J.: Role of Deep Cloud Convection in the
Ozone Budget of the Troposphere, Science, 264, 1759–1761, https://doi.org/10.1126/science.264.5166.1759, 1994.
Midya, S. K., Dey, S. S., and Chakraborty, B.: Variation of the total ozone
column during tropical cyclones over the bay of Bengal and the Arabian
Sea, Meteorol. Atmos. Phys., 117, 63–71, https://doi.org/10.1007/s00703-011-0169-1,
2012.
Molinari, J., Skubis, S., Vollaro, D., and Alsheimer, F.: Potential
vorticity analysisof tropical cyclone intensification, J. Atmos. Sci., 55,
2632–2644, 1998
Nédélec, P., Blot, R., Boulanger, D., Athier, G., Cousin, J.-M.,
Gautron, B., Petzold, A., Volz-Thomas, A., and Thouret, V.: Instrumentation on commercial aircraft for monitoring the atmospheric
composition on a global scale: the IAGOS system, technical overview of ozone
and carbon monoxide measurements, Tellus B, 67, 27791, https://doi.org/10.3402/tellusb.v67.27791, 2015.
Newell, R. E., Hu, W., Wu, Z‐X., Zhu, Y., Akimoto, H., Anderson, B. E., Browell, E. V, Gregory, G. L., Sachse, G. W., Shipham, M. C., Bachmeier, A. S., Bandy, A. R., Thornton, D. C., Blake, D. R., Rowland, F. S., Bradshaw, J. D., Crawford, J. H., Davis, D. D., Sandholm, S. T., Brockett, W., DeGreef, L., Lewis, D., McCormick, D., Monitz, E., Collins Jr., J. E., Heikes, B. G., Merrill, J. T., Kelly, K. K., Liu, S. C., Kondo, Y., Koike, M., Liu, C.-M., Sakamaki, F., Singh, H. B., Dibb, J. E., and Talbot, R. W.: Atmospheric sampling of Supertyphoon
Mireille with NASA DC-8 aircraft on September 27, 1991, during PEM-West
A, J. Geophys. Res., 101, 1853–1871, https://doi.org/10.1029/95JD01374, 1996.
Pan, L. L., Homeyer, C. R., Honomochi, S., Ridley, B. A., Weisman, M., Barth,
M. C., Hair, J. W., Fenn, M. A., Butler, C., Diskin, G. S., Crawford, J. H.,
Ryerson, T. B., Pollack, I., Peischl, J., and Huntrieser, H.: Thunderstorms enhance tropospheric ozone by wrapping and shedding
stratospheric air, Geophys. Res. Lett., 41, 7785–7790, https://doi.org/10.1002/2014GL061921, 2014.
Penn, S.: Ozone and temperature structure in a hurricane, J. Appl.
Meteorol., 4, 212–216, 1965.
Penn, S.: Temperature and ozone variations near the tropopause level over
Hurricane Isbell October 1964, J. Appl. Meteorol., 4, 212–216, 1966.
Petzold, A., Thouret, V., Gerbig, C., Zahn, A., Brenninkmeijer, C. A. M.,
Gallagher, M., Hermann, M., Pontaud, M., Ziereis, H., Boulanger, D.,
Marshall, J., Nédélec, P., Smit, H. G. J., Friess, U., Flaud, J.-M.,
Wahner, A., Cammas, J.-P., Volz-Thomas, A., and IAGOS TEAM:
Global-scale atmosphere monitoring by in-service aircraft – current
achievements and future prospects of the European Research Infrastructure
IAGOS, Tellus B, 67, 1–24, https://doi.org/10.3402/tellusb.v67.28452, 2015.
Preston, A., Fuelberg, H., and Berth., M.: Simulation of chemical
transport by Typhoon Mireille (1991), J. Geophys. Res.-Atmos., 124,
11614–11639, https://doi.org/10.1029/2019JD030446, 2019.
Ramanathan, V., Callis, L., Cess, R., Hansen, J., Isaksen, I., Kuhn, W.,
Lacis, A., Luther, F., Mahlman, J., Reck, R., and Schlesinger, M.: Climate-chemical interactions and effects of changing atmospheric trace
gases, Rev. Geophys., 25, 1441–1482, https://doi.org/10.1029/RG025i007p01441, 1987.
Randel, W. J., Rivoire, L., Pan, L. L., and Honmichi, S. B.: Dry layers in
the tropical troposphere observed during CONTRAST and global behaviour from
GFS analyses, J. Geophys. Res.-Atmos., 121, 14142–14158, https://doi.org/10.1002/2016JD025841, 2016.
Riese, M., Ploeger, F., Rap, A., Vogel, B., Konopka, P., Dameris, M., and
Forster, P.: Impact of uncertainties in atmospheric mixing on simulated
UTLS composition and related radiative effects, J. Geophys. Res., 117,
D16305, https://doi.org/10.1029/2012JD017751, 2012.
Romps, D. M. and Kuang, Z. M.: Overshooting convection in tropical
cyclones, Geophys. Res. Lett., 36, L09804, https://doi.org/10.1029/2009GL037396,
2009.
Roux, F.: ERA-5 data processing, available at: https://mycore.core-cloud.net/index.php/s/vi2SmsVJNVnM4w0, last access: 31 March 2020a.
Roux, F.: IAGOS data processing, available at: https://mycore.core-cloud.net/index.php/s/JWmep21ghplwUG1, last access: 31 March 2020b.
Roux, F.: ERA-5 and IAGOS data processing, available at: https://mycore.core-cloud.net/index.php/s/dscfB8XUqLaw3Pv, last access: 31 March 2020c.
RSMC Tokyo: Annual Report on the Activities of the RSMC Tokyo – Typhoon
Center 2016, Regional Specialized Warning Center, Japan Meteorological
Agency, 95 pp.,
2017.
Skamarock, W. C., Klemp, J. B., Dudhia, J., Gill, D. O., Barker, D. M., Wang, W.,
and Power, J. G.: A description of the advanced research WRF Version-2,
NCAR Tech. Note 468+STR, National Center for Atmospheric Research,
Boulder, Co., USA, 100 pp., https://doi.org/10.5065/D6DZ069T, 2005.
Stohl, A., Bonasoni, P., Cristofanelli, P., Collins, W., Feichter, J.,
Frank, A., Forster, C., Gerasopoulos, E., Gäggeler, H., James, P.,
Kentarchos, T., Kromp-Kolb, H., Krüger, B., Land, C., Meloen, J.,
Papayannis, A., Priller, A., Seibert, P., Sprenger, M., Roelofs, G. J.,
Scheel, H. E., Schnabel, C., Siegmund, P., Tobler, L., Trickl, T., Wernli,
H., Wirth, V., Zanis, P., and Zerefos, C.: Stratosphere-troposphere
exchange: A review, and what we have learned from STACCATO, J. Geophys.
Res., 108, 8516, https://doi.org/10.1029/2002JD002490, 2003.
Stohl, A., Forster, C., Frank, A., Seibert, P., and Wotawa, G.: Technical note: The Lagrangian particle dispersion model FLEXPART version 6.2, Atmos. Chem. Phys., 5, 2461–2474, https://doi.org/10.5194/acp-5-2461-2005, 2005.
Tilmes, S. , Pan, L. L., Hoor, P., Atlas, E., Avery, M. A., Campos, T.,
Christensen, L. E., Diskin, G. S., Gao, R.-S., Herman, R. L., Hintsa, E. J.,
Loewenstein, M., Lopez, J., Paige, M. E., Pittman, J. V., Podolske, J. R.,
Proffitt, M. R., Sachse, G. W., Schiller, C., Schlager, H., Smith, J.,
Spelten, N., Webster, C., Weinheimer, A., and Zondlo, M. A.: An
aircraft-based upper troposphere lower stratosphere O3, CO, and H2O
climatology for the Northern Hemisphere, J. Geophys. Res., 115, D14303,
https://doi.org/10.1029/2009JD012731, 2010.
Venkat Ratnam, M., Ravindra Babu, S., Das, S. S., Basha, G., Krishnamurthy,
B. V., and Venkateswararao, B.: Effect of tropical cyclones on the
stratosphere-troposphere exchange observed using satellite observations over
the north Indian Ocean, Atmos. Chem. Phys., 16, 8581–8591, https://doi.org/10.5194/acp-16-8581-2016, 2016.
Wei, X., Lam, K.-S., Cao, C., Li, H., and He, J.: Dynamics of the
Typhoon Haitang related high ozone episode over Hong Kong, Adv. Meteorol.,
2016, 6089154, https://doi.org/10.1155/2016/6089154, 2016.
Xu, L., Zhang, Y., Wang, F., and Zeng, D.: Simulation of the
electrification of a tropical cyclone using the WRF-ARW model: An idealized
case, J. Meteorol. Res., 28, 453–468, https://doi.org/10.1007/s13351-014-3079-6,
2014.
Xu, W., Rutledge, S. A., and Zhang, W.: Relationships between total
lightning, deep convection, and tropical cyclone intensity change, J.
Geophys. Res., 122, 7047–7063, https://doi.org/10.1002/2017JD027072, 2017.
Yang, J. X., Lau, A. K. H., Fung, J. C. H., Zhou, W., and Wenig, M.: An air
pollution episode and its formation mechanism during the tropical cyclone
Nuris's landfall in a coastal city of south China, Atmos. Environ.,
54, 746–753, https://doi.org/10.1016/j.atmosenv.2011.12.023, 2012.
Yue, X. and Unger, N.: Ozone vegetation damage effects on gross primary
productivity in the United States, Atmos. Chem. Phys., 14, 9137–9153, https://doi.org/10.5194/acp-14-9137-2014, 2014.
Zhan, R. and Wang, Y.: Contribution of tropical cyclones to
stratosphere-troposphere exchange over the northwest Pacific: Estimation
based on AIRS satellite retrievals and ERA-Interim data, J. Geophys.
Res., 117, D12112, https://doi.org/10.1029/2012JD017494, 2012.
Zhang, W., Leung, Y., and Chan, J. L. C.: The analysis of tropical cyclone
tracks in the western North Pacific through data mining, Part I: Tropical
Cyclone Recurvature, J. Appl. Meteor. Climatol., 52, 1394–1416, https://doi.org/10.1175/JAMC-D-12-045.1, 2013.
Zou, X. and Wu, Y.: On the relationship between Total Ozone Mapping
Spectrometer (TOMS) ozone and hurricanes, J. Geophys. Res., 110, D06109,
https://doi.org/10.1029/2004JD005019, 2005.
Short summary
Ozone, carbon monoxide and relative humidity were measured by two China Airlines aircraft equipped with IAGOS instruments during the summer of 2016. We examined landing and take-off profiles near Taipei (Taiwan), in the vicinity of three typhoons, in relation to ERA-5 meteorological reanalyses. Upstream of the storms, these data suggest that air is transported downwards from the stratosphere. Downstream, the troposphere is cleaner and moister due to the uplift of marine boundary layer air.
Ozone, carbon monoxide and relative humidity were measured by two China Airlines aircraft...
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