Articles | Volume 18, issue 8
Atmos. Chem. Phys., 18, 5415–5453, 2018
https://doi.org/10.5194/acp-18-5415-2018
© Author(s) 2018. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Special issue: Quadrennial Ozone Symposium 2016 – Status and trends...
Research article 20 Apr 2018
Research article | 20 Apr 2018
Climatology and long-term evolution of ozone and carbon monoxide in the upper troposphere–lower stratosphere (UTLS) at northern midlatitudes, as seen by IAGOS from 1995 to 2013
Yann Cohen et al.
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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.
Marc Guevara, Oriol Jorba, Albert Soret, Hervé Petetin, Dene Bowdalo, Kim Serradell, Carles Tena, Hugo Denier van der Gon, Jeroen Kuenen, Vincent-Henri Peuch, and Carlos Pérez García-Pando
Atmos. Chem. Phys., 21, 773–797, https://doi.org/10.5194/acp-21-773-2021, https://doi.org/10.5194/acp-21-773-2021, 2021
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Most European countries have imposed lockdowns to combat the spread of the COVID-19 pandemic. Such a socioeconomic disruption has resulted in a sudden drop of atmospheric emissions and air pollution levels. This study quantifies the daily reductions in national emissions and associated levels of nitrogen dioxide (NO2) due to the COVID-19 lockdowns in Europe, by making use of multiple open-access measured activity data as well as artificial intelligence and modelling techniques.
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. Discuss., https://doi.org/10.5194/amt-2020-462, https://doi.org/10.5194/amt-2020-462, 2020
Preprint under review for AMT
Roeland Van Malderen, Dirk De Muer, Hugo De Backer, Deniz Poyraz, Willem W. Verstraeten, Veerle De Bock, Andy Delcloo, Alexander Mangold, Quentin Laffineur, Marc Allaart, Frans Fierens, and Valérie Thouret
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2020-724, https://doi.org/10.5194/acp-2020-724, 2020
Preprint under review for ACP
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In 1969, the main aim of initiating at Uccle the measurements of the vertical distribution of the ozone concentration by means of ozonesondes attached to weather balloons was to improve the weather forecasts. Since then, this measurement technique has barely changed, but the dense, long-term and homogeneous Uccle dataset nowadays remains crucial to study the temporal evolution of ozone from the surface to the stratosphere, and as a backbone for validation of satellite ozone retrievals.
Yann Cohen, Virginie Marécal, Béatrice Josse, and Valérie Thouret
Geosci. Model Dev. Discuss., https://doi.org/10.5194/gmd-2020-328, https://doi.org/10.5194/gmd-2020-328, 2020
Revised manuscript under review for GMD
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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 model monthly grid, limiting the impact of resolution for the evaluation of the modelled chemical fields. We applied it to the CCMI-REFC1SD simulation from the MOCAGE CTM, and notably highlighted a well-reproduced O3 behaviour in the lower stratosphere.
Claire Lamotte, Jonathan Guth, Virginie Marécal, and Martin Cussac
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2020-1040, https://doi.org/10.5194/acp-2020-1040, 2020
Preprint under review for ACP
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Improvements are made in a global CTM by considering a new volcanic SO2 emissions inventory, with more volcanoes referenced and information on the altitude of injection. Better constraining volcanic emissions with this inventory improves global, but mostly local, tropospheric sulfur composition. The tropospheric sulfur budget shows a non-linearity to the volcanic contribution. In particular, considering daily variation in volcanic emissions changes significantly the tropospheric sulfur budget.
Jérôme Barré, Hervé Petetin, Augustin Colette, Marc Guevara, Vincent-Henri Peuch, Laurence Rouil, Richard Engelen, Antje Inness, Johannes Flemming, Carlos Pérez García-Pando, Dene Bowdalo, Frederik Meleux, Camilla Geels, Jesper H. Christensen, Michael Gauss, Anna Benedictow, Svetlana Tsyro, Elmar Friese, Joanna Struzewska, Jacek W. Kaminski, John Douros, Renske Timmermans, Lennart Robertson, Mario Adani, Oriol Jorba, Mathieu Joly, and Rostislav Kouznetsov
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2020-995, https://doi.org/10.5194/acp-2020-995, 2020
Preprint under review for ACP
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This study provides a comprehensive assessment of air quality changes across the main European urban areas induced by the COVID-19 lockdown using satellite observations, surface site measurements and forecasting system from the Copernicus Atmospheric Monitoring Service (CAMS). We demonstrate the importance of accounting for weather and seasonal variability in when calculating such estimates.
Hervé Petetin, Dene Bowdalo, Albert Soret, Marc Guevara, Oriol Jorba, Kim Serradell, and Carlos Pérez García-Pando
Atmos. Chem. Phys., 20, 11119–11141, https://doi.org/10.5194/acp-20-11119-2020, https://doi.org/10.5194/acp-20-11119-2020, 2020
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To control the spread of the COVID-19 coronavirus, the Spanish Government recently implemented a strict lockdown of the population, which strongly reduced the levels of nitrogen dioxide (NO2), one of the most critical air pollutants in Spain. This study quantifies the contribution of the lockdown on these reduced NO2 levels in Spain, taking the confounding effect of meteorology on artificial intelligence techniques into account.
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
Laaziz El Amraoui, Bojan Sič, Andrea Piacentini, Virginie Marécal, Nicolas Frebourg, and Jean-Luc Attié
Atmos. Meas. Tech., 13, 4645–4667, https://doi.org/10.5194/amt-13-4645-2020, https://doi.org/10.5194/amt-13-4645-2020, 2020
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The aim of this paper is to present the assimilation of lidar observations from the CALIOP instrument onboard the CALIPSO satellite in the chemistry-transport model of Météo-France, MOCAGE. We presented the first results of the assimilation of the extinction coefficient observations of the CALIOP lidar instrument during the pre-ChArMEx-TRAQA field campaign. We evaluated the added value of the assimilation product to better document a desert dust transport event compared to the model free run.
Paul D. Hamer, Virginie Marécal, Ryan Hossaini, Michel Pirre, Gisèle Krysztofiak, Franziska Ziska, Andreas Engel, Stephan Sala, Timo Keber, Harald Bönisch, Elliot Atlas, Kirstin Krüger, Martyn Chipperfield, Valery Catoire, Azizan A. Samah, Marcel Dorf, Phang Siew Moi, Hans Schlager, and Klaus Pfeilsticker
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2020-655, https://doi.org/10.5194/acp-2020-655, 2020
Revised manuscript has not been submitted
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Bromoform is a stratospheric ozone depleting gas released by seaweed and plankton that is transported to the stratosphere via convection in the tropics. We study the chemical interactions of bromoform and its derivatives within convective clouds using a cloud scale model and observations. Our findings are that soluble bromine gases are efficiently washed out and removed within the convective clouds and that most bromine is transported vertically to the upper troposphere in the form of bromoform.
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.
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.
Olivier Coopmann, Vincent Guidard, Nadia Fourrié, Béatrice Josse, and Virginie Marécal
Atmos. Meas. Tech., 13, 2659–2680, https://doi.org/10.5194/amt-13-2659-2020, https://doi.org/10.5194/amt-13-2659-2020, 2020
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The objective of this paper is to make a new selection of IASI channels by taking into account inter-channel observation-error correlations. Our selection further reduces the analysis error by 3 % in temperature, 1.8 % in humidity and 0.9 % in ozone compared to Collard’s selection, when using the same number of channels. A selection of 400 IASI channels is proposed at the end of the paper which is able to further reduce analysis errors.
Frank Roux, Hannah Clark, Kuo-Ying Wang, Susanne Rohs, Bastien Sauvage, and Philippe Nédélec
Atmos. Chem. Phys., 20, 3945–3963, https://doi.org/10.5194/acp-20-3945-2020, https://doi.org/10.5194/acp-20-3945-2020, 2020
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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.
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.
Anne-Marlene Blechschmidt, Joaquim Arteta, Adriana Coman, Lyana Curier, Henk Eskes, Gilles Foret, Clio Gielen, Francois Hendrick, Virginie Marécal, Frédérik Meleux, Jonathan Parmentier, Enno Peters, Gaia Pinardi, Ankie J. M. Piters, Matthieu Plu, Andreas Richter, Arjo Segers, Mikhail Sofiev, Álvaro M. Valdebenito, Michel Van Roozendael, Julius Vira, Tim Vlemmix, and John P. Burrows
Atmos. Chem. Phys., 20, 2795–2823, https://doi.org/10.5194/acp-20-2795-2020, https://doi.org/10.5194/acp-20-2795-2020, 2020
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MAX-DOAS tropospheric NO2 vertical column retrievals from a set of European measurement stations are compared to regional air quality models which contribute to the operational Copernicus Atmosphere Monitoring Service (CAMS). Correlations are on the order of 35 %–75 %; large differences occur for individual pollution plumes. The results demonstrate that future model development needs to concentrate on improving representation of diurnal cycles and associated temporal scalings.
Julie M. Nicely, Bryan N. Duncan, Thomas F. Hanisco, Glenn M. Wolfe, Ross J. Salawitch, Makoto Deushi, Amund S. Haslerud, Patrick Jöckel, Béatrice Josse, Douglas E. Kinnison, Andrew Klekociuk, Michael E. Manyin, Virginie Marécal, Olaf Morgenstern, Lee T. Murray, Gunnar Myhre, Luke D. Oman, Giovanni Pitari, Andrea Pozzer, Ilaria Quaglia, Laura E. Revell, Eugene Rozanov, Andrea Stenke, Kane Stone, Susan Strahan, Simone Tilmes, Holger Tost, Daniel M. Westervelt, and Guang Zeng
Atmos. Chem. Phys., 20, 1341–1361, https://doi.org/10.5194/acp-20-1341-2020, https://doi.org/10.5194/acp-20-1341-2020, 2020
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Differences in methane lifetime among global models are large and poorly understood. We use a neural network method and simulations from the Chemistry Climate Model Initiative to quantify the factors influencing methane lifetime spread among models and variations over time. UV photolysis, tropospheric ozone, and nitrogen oxides drive large model differences, while the same factors plus specific humidity contribute to a decreasing trend in methane lifetime between 1980 and 2015.
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.
Yuanhong Zhao, Marielle Saunois, Philippe Bousquet, Xin Lin, Antoine Berchet, Michaela I. Hegglin, Josep G. Canadell, Robert B. Jackson, Didier A. Hauglustaine, Sophie Szopa, Ann R. Stavert, Nathan Luke Abraham, Alex T. Archibald, Slimane Bekki, Makoto Deushi, Patrick Jöckel, Béatrice Josse, Douglas Kinnison, Ole Kirner, Virginie Marécal, Fiona M. O'Connor, David A. Plummer, Laura E. Revell, Eugene Rozanov, Andrea Stenke, Sarah Strode, Simone Tilmes, Edward J. Dlugokencky, and Bo Zheng
Atmos. Chem. Phys., 19, 13701–13723, https://doi.org/10.5194/acp-19-13701-2019, https://doi.org/10.5194/acp-19-13701-2019, 2019
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The role of hydroxyl radical changes in methane trends is debated, hindering our understanding of the methane cycle. This study quantifies how uncertainties in the hydroxyl radical may influence methane abundance in the atmosphere based on the inter-model comparison of hydroxyl radical fields and model simulations of CH4 abundance with different hydroxyl radical scenarios during 2000–2016. We show that hydroxyl radical changes could contribute up to 54 % of model-simulated methane biases.
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.
Kévin Lamy, Thierry Portafaix, Béatrice Josse, Colette Brogniez, Sophie Godin-Beekmann, Hassan Bencherif, Laura Revell, Hideharu Akiyoshi, Slimane Bekki, Michaela I. Hegglin, Patrick Jöckel, Oliver Kirner, Ben Liley, Virginie Marecal, Olaf Morgenstern, Andrea Stenke, Guang Zeng, N. Luke Abraham, Alexander T. Archibald, Neil Butchart, Martyn P. Chipperfield, Glauco Di Genova, Makoto Deushi, Sandip S. Dhomse, Rong-Ming Hu, Douglas Kinnison, Michael Kotkamp, Richard McKenzie, Martine Michou, Fiona M. O'Connor, Luke D. Oman, Giovanni Pitari, David A. Plummer, John A. Pyle, Eugene Rozanov, David Saint-Martin, Kengo Sudo, Taichu Y. Tanaka, Daniele Visioni, and Kohei Yoshida
Atmos. Chem. Phys., 19, 10087–10110, https://doi.org/10.5194/acp-19-10087-2019, https://doi.org/10.5194/acp-19-10087-2019, 2019
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In this study, we simulate the ultraviolet radiation evolution during the 21st century on Earth's surface using the output from several numerical models which participated in the Chemistry-Climate Model Initiative. We present four possible futures which depend on greenhouse gases emissions. The role of ozone-depleting substances, greenhouse gases and aerosols are investigated. Our results emphasize the important role of aerosols for future ultraviolet radiation in the Northern Hemisphere.
Vincent Huijnen, Andrea Pozzer, Joaquim Arteta, Guy Brasseur, Idir Bouarar, Simon Chabrillat, Yves Christophe, Thierno Doumbia, Johannes Flemming, Jonathan Guth, Béatrice Josse, Vlassis A. Karydis, Virginie Marécal, and Sophie Pelletier
Geosci. Model Dev., 12, 1725–1752, https://doi.org/10.5194/gmd-12-1725-2019, https://doi.org/10.5194/gmd-12-1725-2019, 2019
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We report on an evaluation of tropospheric ozone and its precursor gases in three atmospheric chemistry versions as implemented in ECMWF’s Integrated Forecasting System (IFS), referred to as IFS(CB05BASCOE), IFS(MOZART) and IFS(MOCAGE). This configuration of having various chemistry versions within IFS provides a quantification of uncertainties in CAMS trace gas products that are induced by chemistry modelling.
Kai-Lan Chang, Owen R. Cooper, J. Jason West, Marc L. Serre, Martin G. Schultz, Meiyun Lin, Virginie Marécal, Béatrice Josse, Makoto Deushi, Kengo Sudo, Junhua Liu, and Christoph A. Keller
Geosci. Model Dev., 12, 955–978, https://doi.org/10.5194/gmd-12-955-2019, https://doi.org/10.5194/gmd-12-955-2019, 2019
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We developed a new method for combining surface ozone observations from thousands of monitoring sites worldwide with the output from multiple atmospheric chemistry models. The result is a global surface ozone distribution with greater accuracy than any single model can achieve. We focused on an ozone metric relevant to human mortality caused by long-term ozone exposure. Our method can be applied to studies that quantify the impacts of ozone on human health and mortality.
Maxence Descheemaecker, Matthieu Plu, Virginie Marécal, Marine Claeyman, Francis Olivier, Youva Aoun, Philippe Blanc, Lucien Wald, Jonathan Guth, Bojan Sič, Jérôme Vidot, Andrea Piacentini, and Béatrice Josse
Atmos. Meas. Tech., 12, 1251–1275, https://doi.org/10.5194/amt-12-1251-2019, https://doi.org/10.5194/amt-12-1251-2019, 2019
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The future Flexible Combined Imager (FCI) on board MeteoSat Third Generation is expected to improve the detection and the quantification of aerosols. The study assesses the potential of FCI/VIS04 channel for monitoring air pollution in Europe. An observing system simulation experiment in MOCAGE is developed, and they show a large positive impact of the assimilation over a 4-month period and particularly during a severe pollution episode. The added value of geostationary data is also assessed.
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.
Samuel R. Hall, Kirk Ullmann, Michael J. Prather, Clare M. Flynn, Lee T. Murray, Arlene M. Fiore, Gustavo Correa, Sarah A. Strode, Stephen D. Steenrod, Jean-Francois Lamarque, Jonathan Guth, Béatrice Josse, Johannes Flemming, Vincent Huijnen, N. Luke Abraham, and Alex T. Archibald
Atmos. Chem. Phys., 18, 16809–16828, https://doi.org/10.5194/acp-18-16809-2018, https://doi.org/10.5194/acp-18-16809-2018, 2018
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Photolysis (J rates) initiates and drives atmospheric chemistry, and Js are perturbed by factors of 2 by clouds. The NASA Atmospheric Tomography (ATom) Mission provides the first comprehensive observations on how clouds perturb Js through the remote Pacific and Atlantic basins. We compare these cloud-perturbation J statistics with those from nine global chemistry models. While basic patterns agree, there is a large spread across models, and all lack some basic features of the observations.
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.
Pakawat Phalitnonkiat, Peter G. M. Hess, Mircea D. Grigoriu, Gennady Samorodnitsky, Wenxiu Sun, Ellie Beaudry, Simone Tilmes, Makato Deushi, Beatrice Josse, David Plummer, and Kengo Sudo
Atmos. Chem. Phys., 18, 11927–11948, https://doi.org/10.5194/acp-18-11927-2018, https://doi.org/10.5194/acp-18-11927-2018, 2018
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The co-occurrence of heat waves and pollution events and the resulting high mortality rates emphasize the importance of the co-occurrence of pollution and temperature extremes. We analyze ozone and temperature extremes and their joint occurrence over the United States during the summer months (JJA) in measurement data and in model simulations of the present and future climates.
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.
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
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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.
Sandip S. Dhomse, Douglas Kinnison, Martyn P. Chipperfield, Ross J. Salawitch, Irene Cionni, Michaela I. Hegglin, N. Luke Abraham, Hideharu Akiyoshi, Alex T. Archibald, Ewa M. Bednarz, Slimane Bekki, Peter Braesicke, Neal Butchart, Martin Dameris, Makoto Deushi, Stacey Frith, Steven C. Hardiman, Birgit Hassler, Larry W. Horowitz, Rong-Ming Hu, Patrick Jöckel, Beatrice Josse, Oliver Kirner, Stefanie Kremser, Ulrike Langematz, Jared Lewis, Marion Marchand, Meiyun Lin, Eva Mancini, Virginie Marécal, Martine Michou, Olaf Morgenstern, Fiona M. O'Connor, Luke Oman, Giovanni Pitari, David A. Plummer, John A. Pyle, Laura E. Revell, Eugene Rozanov, Robyn Schofield, Andrea Stenke, Kane Stone, Kengo Sudo, Simone Tilmes, Daniele Visioni, Yousuke Yamashita, and Guang Zeng
Atmos. Chem. Phys., 18, 8409–8438, https://doi.org/10.5194/acp-18-8409-2018, https://doi.org/10.5194/acp-18-8409-2018, 2018
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We analyse simulations from the Chemistry-Climate Model Initiative (CCMI) to estimate the return dates of the stratospheric ozone layer from depletion by anthropogenic chlorine and bromine. The simulations from 20 models project that global column ozone will return to 1980 values in 2047 (uncertainty range 2042–2052). Return dates in other regions vary depending on factors related to climate change and importance of chlorine and bromine. Column ozone in the tropics may continue to decline.
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.
Vanessa Brocchi, Gisèle Krysztofiak, Valéry Catoire, Jonathan Guth, Virginie Marécal, Régina Zbinden, Laaziz El Amraoui, François Dulac, and Philippe Ricaud
Atmos. Chem. Phys., 18, 6887–6906, https://doi.org/10.5194/acp-18-6887-2018, https://doi.org/10.5194/acp-18-6887-2018, 2018
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The Mediterranean Basin still suffers from a limited amount of in situ measurements for a good characterization of its environmental state. This study shows that intercontinental transport of very high CO concentrations can affect the upper Mediterranean Basin troposphere. By using modeling, 5- to 12-day eastward transport of biomass burning starting from North America and Siberia impacts the mid-troposphere of the Mediterranean Basin.
Jonathan Guth, Virginie Marécal, Béatrice Josse, Joaquim Arteta, and Paul Hamer
Atmos. Chem. Phys., 18, 4911–4934, https://doi.org/10.5194/acp-18-4911-2018, https://doi.org/10.5194/acp-18-4911-2018, 2018
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.
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
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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.
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.
Reza Shaiganfar, Steffen Beirle, Hugo Denier van der Gon, Sander Jonkers, Jeroen Kuenen, Herve Petetin, Qijie Zhang, Matthias Beekmann, and Thomas Wagner
Atmos. Chem. Phys., 17, 7853–7890, https://doi.org/10.5194/acp-17-7853-2017, https://doi.org/10.5194/acp-17-7853-2017, 2017
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We determine NOx emissions for Paris in summer 2009 and winter 2009/2010 by combining car MAX-DOAS measurements of NO2 with wind fields. We compare the results with simulations from the CHIMERE model. We derive daily average NOx emissions for Paris of 4.0 × 1025 molecules s−1 for summer and of 6.9 × 1025 molecules s−1 in winter. These values are a factor of about 1.4 and 2.0 larger than the corresponding emissions in the MACC-III emission inventory.
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
Daniel Cariolle, Philippe Moinat, Hubert Teyssèdre, Luc Giraud, Béatrice Josse, and Franck Lefèvre
Geosci. Model Dev., 10, 1467–1485, https://doi.org/10.5194/gmd-10-1467-2017, https://doi.org/10.5194/gmd-10-1467-2017, 2017
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This article reports on the development and tests of the adaptive semi-implicit scheme (ASIS) solver for the simulation of atmospheric chemistry. To solve the ordinary differential equations associated with the time evolution of the species concentrations, ASIS adopts a one-step linearized implicit scheme. It conserves mass and has a time-stepping module to control the accuracy of the numerical solution. ASIS was found competitive in terms of computation cost against higher-order schemes.
Olaf Morgenstern, Michaela I. Hegglin, Eugene Rozanov, Fiona M. O'Connor, N. Luke Abraham, Hideharu Akiyoshi, Alexander T. Archibald, Slimane Bekki, Neal Butchart, Martyn P. Chipperfield, Makoto Deushi, Sandip S. Dhomse, Rolando R. Garcia, Steven C. Hardiman, Larry W. Horowitz, Patrick Jöckel, Beatrice Josse, Douglas Kinnison, Meiyun Lin, Eva Mancini, Michael E. Manyin, Marion Marchand, Virginie Marécal, Martine Michou, Luke D. Oman, Giovanni Pitari, David A. Plummer, Laura E. Revell, David Saint-Martin, Robyn Schofield, Andrea Stenke, Kane Stone, Kengo Sudo, Taichu Y. Tanaka, Simone Tilmes, Yousuke Yamashita, Kohei Yoshida, and Guang Zeng
Geosci. Model Dev., 10, 639–671, https://doi.org/10.5194/gmd-10-639-2017, https://doi.org/10.5194/gmd-10-639-2017, 2017
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We present a review of the make-up of 20 models participating in the Chemistry–Climate Model Initiative (CCMI). In comparison to earlier such activities, most of these models comprise a whole-atmosphere chemistry, and several of them include an interactive ocean module. This makes them suitable for studying the interactions of tropospheric air quality, stratospheric ozone, and climate. The paper lays the foundation for other studies using the CCMI simulations for scientific analysis.
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.
François Gheusi, Pierre Durand, Nicolas Verdier, François Dulac, Jean-Luc Attié, Philippe Commun, Brice Barret, Claude Basdevant, Antoine Clenet, Solène Derrien, Alexis Doerenbecher, Laaziz El Amraoui, Alain Fontaine, Emeric Hache, Corinne Jambert, Elodie Jaumouillé, Yves Meyerfeld, Laurent Roblou, and Flore Tocquer
Atmos. Meas. Tech., 9, 5811–5832, https://doi.org/10.5194/amt-9-5811-2016, https://doi.org/10.5194/amt-9-5811-2016, 2016
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Boundary-layer pressurised balloons allow for horizontal multi-day flights in the lower atmosphere, carrying light scientific payloads. Ozonesondes, usually used for balloon soundings have too short a lifetime for such flights. An adaptation is proposed, whereby conventional sondes are operated with short measurement phases alternating with longer periods of dormancy. The sondes were operated over the western Mediterranean, offering an original perspective on tropospheric ozone.
Bojan Sič, Laaziz El Amraoui, Andrea Piacentini, Virginie Marécal, Emanuele Emili, Daniel Cariolle, Michael Prather, and Jean-Luc Attié
Atmos. Meas. Tech., 9, 5535–5554, https://doi.org/10.5194/amt-9-5535-2016, https://doi.org/10.5194/amt-9-5535-2016, 2016
Line Jourdain, Tjarda Jane Roberts, Michel Pirre, and Beatrice Josse
Atmos. Chem. Phys., 16, 12099–12125, https://doi.org/10.5194/acp-16-12099-2016, https://doi.org/10.5194/acp-16-12099-2016, 2016
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Ambrym Volcano (Vanuatu, southwest Pacific) is one of the largest sources of continuous volcanic emissions worldwide. We performed a modeling study that confirms the strong influence of Ambrym emissions during an extreme degassing event of early 2005 on the composition of the atmosphere on the local and regional scales. It also stresses the importance of considering reactive halogen chemistry in the volcanic plume when assessing the impact of volcanic emissions on climate.
Hervé Petetin, Jean Sciare, Michael Bressi, Valérie Gros, Amandine Rosso, Olivier Sanchez, Roland Sarda-Estève, Jean-Eudes Petit, and Matthias Beekmann
Atmos. Chem. Phys., 16, 10419–10440, https://doi.org/10.5194/acp-16-10419-2016, https://doi.org/10.5194/acp-16-10419-2016, 2016
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This paper presents the first combined measurements of both ammonium nitrate aerosols and their gaseous precursors (HNO3, NH3) in the Paris megacity, obtained during the FRANCIPOL and PARTICULES campaigns. This data set is used to investigate the nitrate formation regime within the city, which is particularly important considering the high contribution of nitrates in the fine aerosol pollution of Paris. In addition, it is also used to evaluate the CHIMERE chemistry-transport model.
Raquel A. Silva, J. Jason West, Jean-François Lamarque, Drew T. Shindell, William J. Collins, Stig Dalsoren, Greg Faluvegi, Gerd Folberth, Larry W. Horowitz, Tatsuya Nagashima, Vaishali Naik, Steven T. Rumbold, Kengo Sudo, Toshihiko Takemura, Daniel Bergmann, Philip Cameron-Smith, Irene Cionni, Ruth M. Doherty, Veronika Eyring, Beatrice Josse, Ian A. MacKenzie, David Plummer, Mattia Righi, David S. Stevenson, Sarah Strode, Sophie Szopa, and Guang Zengast
Atmos. Chem. Phys., 16, 9847–9862, https://doi.org/10.5194/acp-16-9847-2016, https://doi.org/10.5194/acp-16-9847-2016, 2016
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Using ozone and PM2.5 concentrations from the ACCMIP ensemble of chemistry-climate models for the four Representative Concentration Pathway scenarios (RCPs), together with projections of future population and baseline mortality rates, we quantify the human premature mortality impacts of future ambient air pollution in 2030, 2050 and 2100, relative to 2000 concentrations. We also estimate the global mortality burden of ozone and PM2.5 in 2000 and each future period.
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. Guth, B. Josse, V. Marécal, M. Joly, and P. Hamer
Geosci. Model Dev., 9, 137–160, https://doi.org/10.5194/gmd-9-137-2016, https://doi.org/10.5194/gmd-9-137-2016, 2016
J. L. Schnell, M. J. Prather, B. Josse, V. Naik, L. W. Horowitz, P. Cameron-Smith, D. Bergmann, G. Zeng, D. A. Plummer, K. Sudo, T. Nagashima, D. T. Shindell, G. Faluvegi, and S. A. Strode
Atmos. Chem. Phys., 15, 10581–10596, https://doi.org/10.5194/acp-15-10581-2015, https://doi.org/10.5194/acp-15-10581-2015, 2015
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We test global chemistry--climate models in their ability to simulate present-day surface ozone. Models are tested against observed hourly ozone from 4217 stations in North America and Europe that are averaged over 1°x1° grid cells. Using novel metrics, we find most models match the shape but not the amplitude of regional summertime diurnal and annual cycles and match the pattern but not the magnitude of summer ozone enhancement. Most also match the observed distribution of extreme episode sizes
P. D. Hamer, K. W. Bowman, D. K. Henze, J.-L. Attié, and V. Marécal
Atmos. Chem. Phys., 15, 10645–10667, https://doi.org/10.5194/acp-15-10645-2015, https://doi.org/10.5194/acp-15-10645-2015, 2015
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Using a simplified air quality forecasting model, we explore how characteristics of air quality observations affect our ability to understand and predict ozone air pollution. We show that the photochemical conditions can strongly influence the observing priorities for ozone prediction, such as which species are observed and how well, when, and how frequently. High-freqency observations of ozone, NOx and HCHO in combination during the morning and afternoon are particularly advantageous.
V. Marécal, V.-H. Peuch, C. Andersson, S. Andersson, J. Arteta, M. Beekmann, A. Benedictow, R. Bergström, B. Bessagnet, A. Cansado, F. Chéroux, A. Colette, A. Coman, R. L. Curier, H. A. C. Denier van der Gon, A. Drouin, H. Elbern, E. Emili, R. J. Engelen, H. J. Eskes, G. Foret, E. Friese, M. Gauss, C. Giannaros, J. Guth, M. Joly, E. Jaumouillé, B. Josse, N. Kadygrov, J. W. Kaiser, K. Krajsek, J. Kuenen, U. Kumar, N. Liora, E. Lopez, L. Malherbe, I. Martinez, D. Melas, F. Meleux, L. Menut, P. Moinat, T. Morales, J. Parmentier, A. Piacentini, M. Plu, A. Poupkou, S. Queguiner, L. Robertson, L. Rouïl, M. Schaap, A. Segers, M. Sofiev, L. Tarasson, M. Thomas, R. Timmermans, Á. Valdebenito, P. van Velthoven, R. van Versendaal, J. Vira, and A. Ung
Geosci. Model Dev., 8, 2777–2813, https://doi.org/10.5194/gmd-8-2777-2015, https://doi.org/10.5194/gmd-8-2777-2015, 2015
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This paper describes the air quality forecasting system over Europe put in place in the Monitoring Atmospheric Composition and Climate projects. It provides daily and 4-day forecasts and analyses for the previous day for major gas and particulate pollutants and their main precursors. These products are based on a multi-model approach using seven state-of-the-art models developed in Europe. An evaluation of the performance of the system is discussed in the paper.
V. Catoire, G. Krysztofiak, C. Robert, M. Chartier, P. Jacquet, C. Guimbaud, P. D. Hamer, and V. Marécal
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amtd-8-9165-2015, https://doi.org/10.5194/amtd-8-9165-2015, 2015
Preprint withdrawn
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A three-channel infrared laser absorption spectrometer has been developed for airborne measurements of trace gases up to the upper troposphere. More than three different species can be measured simultaneously with high time resolution using three individual Continuous Wave Quantum Cascade Lasers coupled to a single Robert multipass optical cell. The first deployment of this spectrometer was realized in convective outflows over South China Sea where enhancements of CO were detected.
H. Petetin, M. Beekmann, A. Colomb, H. A. C. Denier van der Gon, J.-C. Dupont, C. Honoré, V. Michoud, Y. Morille, O. Perrussel, A. Schwarzenboeck, J. Sciare, A. Wiedensohler, and Q. J. Zhang
Atmos. Chem. Phys., 15, 9799–9818, https://doi.org/10.5194/acp-15-9799-2015, https://doi.org/10.5194/acp-15-9799-2015, 2015
M. Sofiev, U. Berger, M. Prank, J. Vira, J. Arteta, J. Belmonte, K.-C. Bergmann, F. Chéroux, H. Elbern, E. Friese, C. Galan, R. Gehrig, D. Khvorostyanov, R. Kranenburg, U. Kumar, V. Marécal, F. Meleux, L. Menut, A.-M. Pessi, L. Robertson, O. Ritenberga, V. Rodinkova, A. Saarto, A. Segers, E. Severova, I. Sauliene, P. Siljamo, B. M. Steensen, E. Teinemaa, M. Thibaudon, and V.-H. Peuch
Atmos. Chem. Phys., 15, 8115–8130, https://doi.org/10.5194/acp-15-8115-2015, https://doi.org/10.5194/acp-15-8115-2015, 2015
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The paper presents the first ensemble modelling experiment for forecasting the atmospheric dispersion of birch pollen in Europe. The study included 7 models of MACC-ENS tested over the season of 2010 and applied for 2013 in forecasting and reanalysis modes. The results were compared with observations in 11 countries, members of European Aeroallergen Network. The models successfully reproduced the timing of the unusually late season of 2013 but had more difficulties with absolute concentration.
R. Shaiganfar, S. Beirle, H. Petetin, Q. Zhang, M. Beekmann, and T. Wagner
Atmos. Meas. Tech., 8, 2827–2852, https://doi.org/10.5194/amt-8-2827-2015, https://doi.org/10.5194/amt-8-2827-2015, 2015
J. Flemming, V. Huijnen, J. Arteta, P. Bechtold, A. Beljaars, A.-M. Blechschmidt, M. Diamantakis, R. J. Engelen, A. Gaudel, A. Inness, L. Jones, B. Josse, E. Katragkou, V. Marecal, V.-H. Peuch, A. Richter, M. G. Schultz, O. Stein, and A. Tsikerdekis
Geosci. Model Dev., 8, 975–1003, https://doi.org/10.5194/gmd-8-975-2015, https://doi.org/10.5194/gmd-8-975-2015, 2015
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We describe modules for atmospheric chemistry, wet and dry deposition and lightning NO production, which have been newly introduced in ECMWF's weather forecasting model. With that model, we want to forecast global air pollution as part of the European Copernicus Atmosphere Monitoring Service. We show that the new model results compare as well or better with in situ and satellite observations of ozone, CO, NO2, SO2 and formaldehyde as the previous model.
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.
B. Sič, L. El Amraoui, V. Marécal, B. Josse, J. Arteta, J. Guth, M. Joly, and P. D. Hamer
Geosci. Model Dev., 8, 381–408, https://doi.org/10.5194/gmd-8-381-2015, https://doi.org/10.5194/gmd-8-381-2015, 2015
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.
E. Hache, J.-L. Attié, C. Tourneur, P. Ricaud, L. Coret, W. A. Lahoz, L. El Amraoui, B. Josse, P. Hamer, J. Warner, X. Liu, K. Chance, M. Höpfner, R. Spurr, V. Natraj, S. Kulawik, A. Eldering, and J. Orphal
Atmos. Meas. Tech., 7, 2185–2201, https://doi.org/10.5194/amt-7-2185-2014, https://doi.org/10.5194/amt-7-2185-2014, 2014
H. Petetin, M. Beekmann, J. Sciare, M. Bressi, A. Rosso, O. Sanchez, and V. Ghersi
Geosci. Model Dev., 7, 1483–1505, https://doi.org/10.5194/gmd-7-1483-2014, https://doi.org/10.5194/gmd-7-1483-2014, 2014
L. Grellier, V. Marécal, B. Josse, P. D. Hamer, T. J. Roberts, A. Aiuppa, and M. Pirre
Geosci. Model Dev. Discuss., https://doi.org/10.5194/gmdd-7-2581-2014, https://doi.org/10.5194/gmdd-7-2581-2014, 2014
Revised manuscript not accepted
R. Hossaini, H. Mantle, M. P. Chipperfield, S. A. Montzka, P. Hamer, F. Ziska, B. Quack, K. Krüger, S. Tegtmeier, E. Atlas, S. Sala, A. Engel, H. Bönisch, T. Keber, D. Oram, G. Mills, C. Ordóñez, A. Saiz-Lopez, N. Warwick, Q. Liang, W. Feng, F. Moore, B. R. Miller, V. Marécal, N. A. D. Richards, M. Dorf, and K. Pfeilsticker
Atmos. Chem. Phys., 13, 11819–11838, https://doi.org/10.5194/acp-13-11819-2013, https://doi.org/10.5194/acp-13-11819-2013, 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
K. M. Longo, S. R. Freitas, M. Pirre, V. Marécal, L. F. Rodrigues, J. Panetta, M. F. Alonso, N. E. Rosário, D. S. Moreira, M. S. Gácita, J. Arteta, R. Fonseca, R. Stockler, D. M. Katsurayama, A. Fazenda, and M. Bela
Geosci. Model Dev., 6, 1389–1405, https://doi.org/10.5194/gmd-6-1389-2013, https://doi.org/10.5194/gmd-6-1389-2013, 2013
J.-F. Lamarque, F. Dentener, J. McConnell, C.-U. Ro, M. Shaw, R. Vet, D. Bergmann, P. Cameron-Smith, S. Dalsoren, R. Doherty, G. Faluvegi, S. J. Ghan, B. Josse, Y. H. Lee, I. A. MacKenzie, D. Plummer, D. T. Shindell, R. B. Skeie, D. S. Stevenson, S. Strode, G. Zeng, M. Curran, D. Dahl-Jensen, S. Das, D. Fritzsche, and M. Nolan
Atmos. Chem. Phys., 13, 7997–8018, https://doi.org/10.5194/acp-13-7997-2013, https://doi.org/10.5194/acp-13-7997-2013, 2013
P. D. Hamer, V. Marécal, R. Hossaini, M. Pirre, N. Warwick, M. Chipperfield, A. A. Samah, N. Harris, A. Robinson, B. Quack, A. Engel, K. Krüger, E. Atlas, K. Subramaniam, D. Oram, E. Leedham, G. Mills, K. Pfeilsticker, S. Sala, T. Keber, H. Bönisch, L. K. Peng, M. S. M. Nadzir, P. T. Lim, A. Mujahid, A. Anton, H. Schlager, V. Catoire, G. Krysztofiak, S. Fühlbrügge, M. Dorf, and W. T. Sturges
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acpd-13-20611-2013, https://doi.org/10.5194/acpd-13-20611-2013, 2013
Revised manuscript not accepted
V. Naik, A. Voulgarakis, A. M. Fiore, L. W. Horowitz, J.-F. Lamarque, M. Lin, M. J. Prather, P. J. Young, D. Bergmann, P. J. Cameron-Smith, I. Cionni, W. J. Collins, S. B. Dalsøren, R. Doherty, V. Eyring, G. Faluvegi, G. A. Folberth, B. Josse, Y. H. Lee, I. A. MacKenzie, T. Nagashima, T. P. C. van Noije, D. A. Plummer, M. Righi, S. T. Rumbold, R. Skeie, D. T. Shindell, D. S. Stevenson, S. Strode, K. Sudo, S. Szopa, and G. Zeng
Atmos. Chem. Phys., 13, 5277–5298, https://doi.org/10.5194/acp-13-5277-2013, https://doi.org/10.5194/acp-13-5277-2013, 2013
K. W. Bowman, D. T. Shindell, H. M. Worden, J.F. Lamarque, P. J. Young, D. S. Stevenson, Z. Qu, M. de la Torre, D. Bergmann, P. J. Cameron-Smith, W. J. Collins, R. Doherty, S. B. Dalsøren, G. Faluvegi, G. Folberth, L. W. Horowitz, B. M. Josse, Y. H. Lee, I. A. MacKenzie, G. Myhre, T. Nagashima, V. Naik, D. A. Plummer, S. T. Rumbold, R. B. Skeie, S. A. Strode, K. Sudo, S. Szopa, A. Voulgarakis, G. Zeng, S. S. Kulawik, A. M. Aghedo, and J. R. Worden
Atmos. Chem. Phys., 13, 4057–4072, https://doi.org/10.5194/acp-13-4057-2013, https://doi.org/10.5194/acp-13-4057-2013, 2013
D. S. Stevenson, P. J. Young, V. Naik, J.-F. Lamarque, D. T. Shindell, A. Voulgarakis, R. B. Skeie, S. B. Dalsoren, G. Myhre, T. K. Berntsen, G. A. Folberth, S. T. Rumbold, W. J. Collins, I. A. MacKenzie, R. M. Doherty, G. Zeng, T. P. C. van Noije, A. Strunk, D. Bergmann, P. Cameron-Smith, D. A. Plummer, S. A. Strode, L. Horowitz, Y. H. Lee, S. Szopa, K. Sudo, T. Nagashima, B. Josse, I. Cionni, M. Righi, V. Eyring, A. Conley, K. W. Bowman, O. Wild, and A. Archibald
Atmos. Chem. Phys., 13, 3063–3085, https://doi.org/10.5194/acp-13-3063-2013, https://doi.org/10.5194/acp-13-3063-2013, 2013
A. Voulgarakis, V. Naik, J.-F. Lamarque, D. T. Shindell, P. J. Young, M. J. Prather, O. Wild, R. D. Field, D. Bergmann, P. Cameron-Smith, I. Cionni, W. J. Collins, S. B. Dalsøren, R. M. Doherty, V. Eyring, G. Faluvegi, G. A. Folberth, L. W. Horowitz, B. Josse, I. A. MacKenzie, T. Nagashima, D. A. Plummer, M. Righi, S. T. Rumbold, D. S. Stevenson, S. A. Strode, K. Sudo, S. Szopa, and G. Zeng
Atmos. Chem. Phys., 13, 2563–2587, https://doi.org/10.5194/acp-13-2563-2013, https://doi.org/10.5194/acp-13-2563-2013, 2013
P. J. Young, A. T. Archibald, K. W. Bowman, J.-F. Lamarque, V. Naik, D. S. Stevenson, S. Tilmes, A. Voulgarakis, O. Wild, D. Bergmann, P. Cameron-Smith, I. Cionni, W. J. Collins, S. B. Dalsøren, R. M. Doherty, V. Eyring, G. Faluvegi, L. W. Horowitz, B. Josse, Y. H. Lee, I. A. MacKenzie, T. Nagashima, D. A. Plummer, M. Righi, S. T. Rumbold, R. B. Skeie, D. T. Shindell, S. A. Strode, K. Sudo, S. Szopa, and G. Zeng
Atmos. Chem. Phys., 13, 2063–2090, https://doi.org/10.5194/acp-13-2063-2013, https://doi.org/10.5194/acp-13-2063-2013, 2013
J.-F. Lamarque, D. T. Shindell, B. Josse, P. J. Young, I. Cionni, V. Eyring, D. Bergmann, P. Cameron-Smith, W. J. Collins, R. Doherty, S. Dalsoren, G. Faluvegi, G. Folberth, S. J. Ghan, L. W. Horowitz, Y. H. Lee, I. A. MacKenzie, T. Nagashima, V. Naik, D. Plummer, M. Righi, S. T. Rumbold, M. Schulz, R. B. Skeie, D. S. Stevenson, S. Strode, K. Sudo, S. Szopa, A. Voulgarakis, and G. Zeng
Geosci. Model Dev., 6, 179–206, https://doi.org/10.5194/gmd-6-179-2013, https://doi.org/10.5194/gmd-6-179-2013, 2013
G. Lacressonnière, V.-H. Peuch, J. Arteta, B. Josse, M. Joly, V. Marécal, D. Saint Martin, M. Déqué, and L. Watson
Geosci. Model Dev., 5, 1565–1587, https://doi.org/10.5194/gmd-5-1565-2012, https://doi.org/10.5194/gmd-5-1565-2012, 2012
Related subject area
Subject: Gases | Research Activity: Field Measurements | Altitude Range: Troposphere | Science Focus: Chemistry (chemical composition and reactions)
Halogen activation in the plume of Masaya volcano: field observations and box model investigations
Decoupling of urban CO2 and air pollutant emission reductions during the European SARS-CoV-2 lockdown
Atmospheric VOC measurements at a High Arctic site: characteristics and source apportionment
Evaluating the sensitivity of radical chemistry and ozone formation to ambient VOCs and NOx in Beijing
Global trends and European emissions of tetrafluoromethane (CF4), hexafluoroethane (C2F6) and octafluoropropane (C3F8)
Non-target and suspect characterisation of organic contaminants in ambient air – Part 1: Combining a novel sample clean-up method with comprehensive two-dimensional gas chromatography
Low-NO atmospheric oxidation pathways in a polluted megacity
Seasonal variation and origins of volatile organic compounds observed during 2 years at a western Mediterranean remote background site (Ersa, Cape Corsica)
Ambient nitro-aromatic compounds – biomass burning versus secondary formation in rural China
Secular change in atmospheric Ar∕N2 and its implications for ocean heat uptake and Brewer–Dobson circulation
Pan-European rural monitoring network shows dominance of NH3 gas and NH4NO3 aerosol in inorganic atmospheric pollution load
Measurement report: Changing characteristics of atmospheric CH4 in the Tibetan Plateau: records from 1994 to 2019 at the Mount Waliguan station
Soil–atmosphere exchange flux of total gaseous mercury (TGM) at subtropical and temperate forest catchments
Measurement report: Long-term variations in carbon monoxide at a background station in China's Yangtze River Delta region
UK surface NO2 levels dropped by 42 % during the COVID-19 lockdown: impact on surface O3
Airborne measurements of fire emission factors for African biomass burning sampled during the MOYA campaign
Surface–atmosphere fluxes of volatile organic compounds in Beijing
Elevated levels of OH observed in haze events during wintertime in central Beijing
Measurement report: Important contributions of oxygenated compounds to emissions and chemistry of volatile organic compounds in urban air
Characterisation of African biomass burning plumes and impacts on the atmospheric composition over the south-west Indian Ocean
Measurement report: Aircraft observations of ozone, nitrogen oxides, and volatile organic compounds over Hebei Province, China
A measurement and model study on ozone characteristics in marine air at a remote island station and its interaction with urban ozone air quality in Shanghai, China
Measurements of higher alkanes using NO+ chemical ionization in PTR-ToF-MS: important contributions of higher alkanes to secondary organic aerosols in China
Long-term variations in ozone levels in the troposphere and lower stratosphere over Beijing: observations and model simulations
Variability in gaseous elemental mercury at Villum Research Station, Station Nord, in North Greenland from 1999 to 2017
Role of the dew water on the ground surface in HONO distribution: a case measurement in Melpitz
Where there is smoke there is mercury: Assessing boreal forest fire mercury emissions using aircraft and highlighting uncertainties associated with upscaling emissions estimates
Emission of biogenic volatile organic compounds from warm and oligotrophic seawater in the Eastern Mediterranean
Impact of the South Asian monsoon outflow on atmospheric hydroperoxides in the upper troposphere
Measurement report: Exploring the NH3 behaviours at urban and suburban Beijing: Comparison and implications
Non-methane hydrocarbon (NMHC) fingerprints of major urban and agricultural emission sources for use in source apportionment studies
Estimation of reactive inorganic iodine fluxes in the Indian and Southern Ocean marine boundary layer
Observations of atmospheric 14CO2 at Anmyeondo GAW station, South Korea: implications for fossil fuel CO2 and emission ratios
Sources of nitrous acid (HONO) in the upper boundary layer and lower free troposphere of the North China Plain: insights from the Mount Tai Observatory
Measurement report: Short-term variation in ammonia concentrations in an urban area increased by mist evaporation and emissions from a forest canopy with bird droppings
Speciation of VOC emissions related to offshore North Sea oil and gas production
Sources and sinks driving sulfuric acid concentrations in contrasting environments: implications on proxy calculations
Observed decreases in on-road CO2 concentrations in Beijing during COVID-19
Characterizing the spatiotemporal nitrogen stable isotopic composition of ammonia in vehicle plumes
Assessing contributions of natural surface and anthropogenic emissions to atmospheric mercury in a fast-developing region of eastern China from 2015 to 2018
Measurements of carbonyl compounds around the Arabian Peninsula: overview and model comparison
Retrieving tropospheric NO2 vertical column densities around the city of Beijing and estimating NOx emissions based on car MAX-DOAS measurements
Measurement report: Statistical modelling of long-term trends of atmospheric inorganic gaseous species within proximity of the pollution hotspot in South Africa
Global-scale distribution of ozone in the remote troposphere from the ATom and HIPPO airborne field missions
Investigation of several proxies to estimate sulfuric acid concentration in volcanic plume conditions
Atmospheric mercury in the Southern Hemisphere – Part 2: Source apportionment analysis at Cape Point station, South Africa
Identifying and Quantifying Source Contributions of Air Quality Contaminants during Unconventional Shale Gas Extraction
Polycyclic aromatic hydrocarbons (PAHs) and oxy- and nitro-PAHs in ambient air of the Arctic town Longyearbyen, Svalbard
Spatiotemporal Variation, Sources, and Secondary Transformation Potential of VOCs in Xi’an, China
Source characterization of volatile organic compounds measured by proton-transfer-reaction time-of-flight mass spectrometers in Delhi, India
Julian Rüdiger, Alexandra Gutmann, Nicole Bobrowski, Marcello Liotta, J. Maarten de Moor, Rolf Sander, Florian Dinger, Jan-Lukas Tirpitz, Martha Ibarra, Armando Saballos, María Martínez, Elvis Mendoza, Arnoldo Ferrufino, John Stix, Juan Valdés, Jonathan M. Castro, and Thorsten Hoffmann
Atmos. Chem. Phys., 21, 3371–3393, https://doi.org/10.5194/acp-21-3371-2021, https://doi.org/10.5194/acp-21-3371-2021, 2021
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We present an innovative approach to study halogen chemistry in the plume of Masaya volcano in Nicaragua. An unique data set was collected using multiple techniques, including drones. These data enabled us to determine the fraction of activation of the respective halogens at various plume ages, where in-mixing of ambient air causes chemical reactions. An atmospheric chemistry box model was employed to further examine the field results and help our understanding of volcanic plume chemistry.
Christian Lamprecht, Martin Graus, Marcus Striednig, Michael Stichaner, and Thomas Karl
Atmos. Chem. Phys., 21, 3091–3102, https://doi.org/10.5194/acp-21-3091-2021, https://doi.org/10.5194/acp-21-3091-2021, 2021
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The first European SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) wave and associated lockdown provided a unique sensitivity experiment to study air pollution. We find significantly different emission trajectories between classical air pollution and climate gases (e.g., carbon dioxide). The analysis suggests that European policies, shifting residential, public, and commercial energy demand towards cleaner combustion, have helped to improve air quality more than expected.
Jakob B. Pernov, Rossana Bossi, Thibaut Lebourgeois, Jacob K. Nøjgaard, Rupert Holzinger, Jens L. Hjorth, and Henrik Skov
Atmos. Chem. Phys., 21, 2895–2916, https://doi.org/10.5194/acp-21-2895-2021, https://doi.org/10.5194/acp-21-2895-2021, 2021
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Volatile organic compounds (VOCs) are an important constituent in the Arctic atmosphere due to their effect on aerosol and ozone formation. However, an understanding of their sources is lacking. This research presents a multiseason high-time-resolution dataset of VOCs in the Arctic and details their temporal characteristics and source apportionment. Four sources were identified: biomass burning, marine cryosphere, background, and Arctic haze.
Lisa K. Whalley, Eloise J. Slater, Robert Woodward-Massey, Chunxiang Ye, James D. Lee, Freya Squires, James R. Hopkins, Rachel E. Dunmore, Marvin Shaw, Jacqueline F. Hamilton, Alastair C. Lewis, Archit Mehra, Stephen D. Worrall, Asan Bacak, Thomas J. Bannan, Hugh Coe, Carl J. Percival, Bin Ouyang, Roderic L. Jones, Leigh R. Crilley, Louisa J. Kramer, William J. Bloss, Tuan Vu, Simone Kotthaus, Sue Grimmond, Yele Sun, Weiqi Xu, Siyao Yue, Lujie Ren, W. Joe F. Acton, C. Nicholas Hewitt, Xinming Wang, Pingqing Fu, and Dwayne E. Heard
Atmos. Chem. Phys., 21, 2125–2147, https://doi.org/10.5194/acp-21-2125-2021, https://doi.org/10.5194/acp-21-2125-2021, 2021
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To understand how emission controls will impact ozone, an understanding of the sources and sinks of OH and the chemical cycling between peroxy radicals is needed. This paper presents measurements of OH, HO2 and total RO2 taken in central Beijing. The radical observations are compared to a detailed chemistry model, which shows that under low NO conditions, there is a missing OH source. Under high NOx conditions, the model under-predicts RO2 and impacts our ability to model ozone.
Daniel Say, Alistair J. Manning, Luke M. Western, Dickon Young, Adam Wisher, Matthew Rigby, Stefan Reimann, Martin K. Vollmer, Michela Maione, Jgor Arduini, Paul B. Krummel, Jens Mühle, Christina M. Harth, Brendan Evans, Ray F. Weiss, Ronald G. Prinn, and Simon O'Doherty
Atmos. Chem. Phys., 21, 2149–2164, https://doi.org/10.5194/acp-21-2149-2021, https://doi.org/10.5194/acp-21-2149-2021, 2021
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Perfluorocarbons (PFCs) are potent greenhouse gases with exceedingly long lifetimes. We used atmospheric measurements from a global monitoring network to track the accumulation of these gases in the atmosphere. In the case of the two most abundant PFCs, recent measurements indicate that global emissions are increasing. In Europe, we used a model to estimate regional PFC emissions. Our results show that there was no significant decline in northwest European PFC emissions between 2010 and 2019.
Laura Röhler, Pernilla Bohlin-Nizzetto, Pawel Rostkowski, Roland Kallenborn, and Martin Schlabach
Atmos. Chem. Phys., 21, 1697–1716, https://doi.org/10.5194/acp-21-1697-2021, https://doi.org/10.5194/acp-21-1697-2021, 2021
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A novel non-destructive, sulfuric-acid-free clean-up method for high-volume air samples was developed and evaluated with organic chemicals covering a wide range of polarities (logP 2–11). This method, providing quantitative results of comparable quality to traditional methods, was combined with newly developed data treatment strategies for simultaneous suspect and non-target screening. The application to air samples from southern Norway revealed 90 new potential chemicals of emerging concern.
Mike J. Newland, Daniel J. Bryant, Rachel E. Dunmore, Thomas J. Bannan, W. Joe F. Acton, Ben Langford, James R. Hopkins, Freya A. Squires, William Dixon, William S. Drysdale, Peter D. Ivatt, Mathew J. Evans, Peter M. Edwards, Lisa K. Whalley, Dwayne E. Heard, Eloise J. Slater, Robert Woodward-Massey, Chunxiang Ye, Archit Mehra, Stephen D. Worrall, Asan Bacak, Hugh Coe, Carl J. Percival, C. Nicholas Hewitt, James D. Lee, Tianqu Cui, Jason D. Surratt, Xinming Wang, Alastair C. Lewis, Andrew R. Rickard, and Jacqueline F. Hamilton
Atmos. Chem. Phys., 21, 1613–1625, https://doi.org/10.5194/acp-21-1613-2021, https://doi.org/10.5194/acp-21-1613-2021, 2021
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We report the formation of secondary pollutants in the urban megacity of Beijing that are typically associated with remote regions such as rainforests. This is caused by extremely low levels of nitric oxide (NO), typically expected to be high in urban areas, observed in the afternoon. This work has significant implications for how we understand atmospheric chemistry in the urban environment and thus for how to implement effective policies to improve urban air quality.
Cécile Debevec, Stéphane Sauvage, Valérie Gros, Thérèse Salameh, Jean Sciare, François Dulac, and Nadine Locoge
Atmos. Chem. Phys., 21, 1449–1484, https://doi.org/10.5194/acp-21-1449-2021, https://doi.org/10.5194/acp-21-1449-2021, 2021
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This study provides a better characterization of the seasonal variations in VOC sources impacting the western Mediterranean region, based on a comprehensive chemical composition measured over 25 months at a representative receptor site (Ersa) and by determining factors controlling their temporal variations. Some insights into dominant drivers for VOC concentration variations in Europe are also provided, built on comparisons of Ersa observations with the concomitant ones of 17 European sites.
Christian Mark Garcia Salvador, Rongzhi Tang, Michael Priestley, Linjie Li, Epameinondas Tsiligiannis, Michael Le Breton, Wenfei Zhu, Limin Zeng, Hui Wang, Ying Yu, Min Hu, Song Guo, and Mattias Hallquist
Atmos. Chem. Phys., 21, 1389–1406, https://doi.org/10.5194/acp-21-1389-2021, https://doi.org/10.5194/acp-21-1389-2021, 2021
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High-frequency online measurement of gas- and particle-phase nitro-aromatic compounds (NACs) at a rural site in China, heavily influenced by biomass burning events, enabled the analysis of the production pathway of NACs, including an explanation of strong persistence in the daytime. The contribution of secondary processes was significant, even during the dominant wintertime influence of primary emissions, suggesting the important role of regional secondary chemistry, i.e. photochemical smog.
Shigeyuki Ishidoya, Satoshi Sugawara, Yasunori Tohjima, Daisuke Goto, Kentaro Ishijima, Yosuke Niwa, Nobuyuki Aoki, and Shohei Murayama
Atmos. Chem. Phys., 21, 1357–1373, https://doi.org/10.5194/acp-21-1357-2021, https://doi.org/10.5194/acp-21-1357-2021, 2021
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The surface Ar / N2 ratio showed not only secular increasing trends, but also interannual variations in phase with the global ocean heat content (OHC). Sensitivity test by using a two-dimensional model indicated that the secular trend in the Ar / N2 ratio is modified by the gravitational separation in the stratosphere. The analytical results imply that the surface Ar/N2 ratio is an important tracer for detecting spatiotemporally integrated changes in OHC and stratospheric circulation.
Y. Sim Tang, Chris R. Flechard, Ulrich Dämmgen, Sonja Vidic, Vesna Djuricic, Marta Mitosinkova, Hilde T. Uggerud, Maria J. Sanz, Ivan Simmons, Ulrike Dragosits, Eiko Nemitz, Marsailidh Twigg, Netty van Dijk, Yannick Fauvel, Francisco Sanz, Martin Ferm, Cinzia Perrino, Maria Catrambone, David Leaver, Christine F. Braban, J. Neil Cape, Mathew R. Heal, and Mark A. Sutton
Atmos. Chem. Phys., 21, 875–914, https://doi.org/10.5194/acp-21-875-2021, https://doi.org/10.5194/acp-21-875-2021, 2021
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The DELTA® approach provided speciated, monthly data on reactive gases (NH3, HNO3, SO2, HCl) and aerosols (NH4+, NO3−, SO42−, Cl−, Na+) across Europe (2006–2010). Differences in spatial and temporal concentrations and patterns between geographic regions and four ecosystem types were captured. NH3 and NH4NO3 were dominant components, highlighting their growing relative importance in ecosystem impacts (acidification, eutrophication) and human health effects (NH3 as a precursor to PM2.5) in Europe.
Shuo Liu, Shuangxi Fang, Peng Liu, Miao Liang, Minrui Guo, and Zhaozhong Feng
Atmos. Chem. Phys., 21, 393–413, https://doi.org/10.5194/acp-21-393-2021, https://doi.org/10.5194/acp-21-393-2021, 2021
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We analyzed 26-year CH4 measurements at Mount Waliguan in the Tibetan Plateau, China. The CH4 increased ~ 133 parts per billion (ppb) with a rate of 5.1 ± 0.1 ppb yr-1 from 1994 to 2019. Major source regions were identified in northeast and southwest. The influence of human activities is more and more serious, and northern India has possibly become a stronger contributor than city regions were in the past. It has become urgent to control CH4 emissions in the Tibetan Plateau.
Jun Zhou, Zhangwei Wang, Xiaoshan Zhang, Charles T. Driscoll, and Che-Jen Lin
Atmos. Chem. Phys., 20, 16117–16133, https://doi.org/10.5194/acp-20-16117-2020, https://doi.org/10.5194/acp-20-16117-2020, 2020
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Mercury (Hg) emissions from natural resources have a large uncertainty, which is mainly derived from the forest. A long-term and multiplot (10) study of soil–air fluxes at subtropical and temperate forests was conducted. Forest soils are an important atmospheric Hg source, especially for subtropical forests. The compensation points imply that the atmospheric Hg concentration plays a critical role in inhibiting Hg emissions from the forest floor. Climate change can enhance soil Hg emissions.
Yijing Chen, Qianli Ma, Weili Lin, Xiaobin Xu, Jie Yao, and Wei Gao
Atmos. Chem. Phys., 20, 15969–15982, https://doi.org/10.5194/acp-20-15969-2020, https://doi.org/10.5194/acp-20-15969-2020, 2020
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CO is one of the major air pollutants. Our study showed that the long-term CO levels at a background station in one of the most developed areas of China decreased significantly and verified that this downward trend was attributed to the decrease in anthropogenic emissions, which indicated that the adopted pollution control policies were effective. Also, this decrease has an implication for the atmospheric chemistry considering the negative correlation between CO levels and OH radical's lifetime.
James D. Lee, Will S. Drysdale, Doug P. Finch, Shona E. Wilde, and Paul I. Palmer
Atmos. Chem. Phys., 20, 15743–15759, https://doi.org/10.5194/acp-20-15743-2020, https://doi.org/10.5194/acp-20-15743-2020, 2020
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Efforts to prevent the COVID-19 virus spreading across the globe have included travel restrictions and the closure of workplaces, leading to a significant drop in emissions of primary air pollutants. This provides for a unique opportunity to examine how air pollutant concentrations respond to an abrupt and prolonged reduction. We examine how NO2 and O3 have been affected at several urban measurement sites in the UK. We look at the change in NO2 compared to previous years and the effect on O3.
Patrick A. Barker, Grant Allen, Martin Gallagher, Joseph R. Pitt, Rebecca E. Fisher, Thomas Bannan, Euan G. Nisbet, Stéphane J.-B. Bauguitte, Dominika Pasternak, Samuel Cliff, Marina B. Schimpf, Archit Mehra, Keith N. Bower, James D. Lee, Hugh Coe, and Carl J. Percival
Atmos. Chem. Phys., 20, 15443–15459, https://doi.org/10.5194/acp-20-15443-2020, https://doi.org/10.5194/acp-20-15443-2020, 2020
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Africa is estimated to account for approximately 52 % of global biomass burning (BB) carbon emissions. Despite this, there has been little previous in situ study of African BB emissions. This work presents BB emission factors for various atmospheric trace gases sampled from an aircraft in two distinct areas of Africa (Senegal and Uganda). Intracontinental variability in biomass burning methane emission is identified, which is attributed to difference in the specific fuel mixtures burnt.
W. Joe F. Acton, Zhonghui Huang, Brian Davison, Will S. Drysdale, Pingqing Fu, Michael Hollaway, Ben Langford, James Lee, Yanhui Liu, Stefan Metzger, Neil Mullinger, Eiko Nemitz, Claire E. Reeves, Freya A. Squires, Adam R. Vaughan, Xinming Wang, Zhaoyi Wang, Oliver Wild, Qiang Zhang, Yanli Zhang, and C. Nicholas Hewitt
Atmos. Chem. Phys., 20, 15101–15125, https://doi.org/10.5194/acp-20-15101-2020, https://doi.org/10.5194/acp-20-15101-2020, 2020
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Air quality in Beijing is of concern to both policy makers and the general public. In order to address concerns about air quality it is vital that the sources of atmospheric pollutants are understood. This work presents the first top-down measurement of volatile organic compound (VOC) emissions in Beijing. These measurements are used to evaluate the emissions inventory and assess the impact of VOC emission from the city centre on atmospheric chemistry.
Eloise J. Slater, Lisa K. Whalley, Robert Woodward-Massey, Chunxiang Ye, James D. Lee, Freya Squires, James R. Hopkins, Rachel E. Dunmore, Marvin Shaw, Jacqueline F. Hamilton, Alastair C. Lewis, Leigh R. Crilley, Louisa Kramer, William Bloss, Tuan Vu, Yele Sun, Weiqi Xu, Siyao Yue, Lujie Ren, W. Joe F. Acton, C. Nicholas Hewitt, Xinming Wang, Pingqing Fu, and Dwayne E. Heard
Atmos. Chem. Phys., 20, 14847–14871, https://doi.org/10.5194/acp-20-14847-2020, https://doi.org/10.5194/acp-20-14847-2020, 2020
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The paper details atmospheric chemistry in a megacity (Beijing), focussing on radicals which mediate the formation of secondary pollutants such as ozone and particles. Highly polluted conditions were experienced, including the highest ever levels of nitric oxide (NO), with simultaneous radical measurements. Radical concentrations were large during "haze" events, demonstrating active photochemistry. Modelling showed that our understanding of the chemistry at high NOx levels is incomplete.
Caihong Wu, Chaomin Wang, Sihang Wang, Wenjie Wang, Bin Yuan, Jipeng Qi, Baolin Wang, Hongli Wang, Chen Wang, Wei Song, Xinming Wang, Weiwei Hu, Shengrong Lou, Chenshuo Ye, Yuwen Peng, Zelong Wang, Yibo Huangfu, Yan Xie, Manni Zhu, Junyu Zheng, Xuemei Wang, Bin Jiang, Zhanyi Zhang, and Min Shao
Atmos. Chem. Phys., 20, 14769–14785, https://doi.org/10.5194/acp-20-14769-2020, https://doi.org/10.5194/acp-20-14769-2020, 2020
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Based on measurements from an online mass spectrometer, we quantify volatile organic compound (VOC) concentrations from numerous ions of the mass spectrometer, using information from laboratory-obtained calibration results. We find that most VOC concentrations are from oxygenated VOCs (OVOCs). We further show that these OVOCs also contribute significantly to OH reactivity. Our results suggest the important role of OVOCs in VOC emissions and chemistry in urban air.
Bert Verreyken, Crist Amelynck, Jérôme Brioude, Jean-François Müller, Niels Schoon, Nicolas Kumps, Aurélie Colomb, Jean-Marc Metzger, Christopher F. Lee, Theodore K. Koenig, Rainer Volkamer, and Trissevgeni Stavrakou
Atmos. Chem. Phys., 20, 14821–14845, https://doi.org/10.5194/acp-20-14821-2020, https://doi.org/10.5194/acp-20-14821-2020, 2020
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Biomass burning (BB) plumes arriving at the Maïdo observatory located in the south-west Indian Ocean during August 2018 and August 2019 are studied using trace gas measurements, Lagrangian transport models and the CAMS near-real-time atmospheric composition service. We investigate (i) secondary production of volatile organic compounds during transport, (ii) efficacy of the CAMS model to reproduce the chemical makeup of BB plumes and (iii) the impact of BB on the remote marine boundary layer.
Sarah E. Benish, Hao He, Xinrong Ren, Sandra J. Roberts, Ross J. Salawitch, Zhanqing Li, Fei Wang, Yuying Wang, Fang Zhang, Min Shao, Sihua Lu, and Russell R. Dickerson
Atmos. Chem. Phys., 20, 14523–14545, https://doi.org/10.5194/acp-20-14523-2020, https://doi.org/10.5194/acp-20-14523-2020, 2020
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Airborne observations of ozone and related pollutants show smog was pervasive in spring 2016 over Hebei Province, China. We find high amounts of ozone precursors throughout and even above the PBL, continuing to generate ozone at high rates to be potentially transported downwind. Concentrations even in the rural areas of this highly industrialized province promote widespread ozone production, and we show that to improve air quality over Hebei both NOx and VOCs should be targeted.
Yixuan Gu, Fengxia Yan, Jianming Xu, Yuanhao Qu, Wei Gao, Fangfang He, and Hong Liao
Atmos. Chem. Phys., 20, 14361–14375, https://doi.org/10.5194/acp-20-14361-2020, https://doi.org/10.5194/acp-20-14361-2020, 2020
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High levels and statistically insignificant changes of ozone are detected at a remote monitoring site on Sheshan Island in Shanghai, China, from 2012 to 2017; 6-year observations suggest regional transport exerted minimum influence on the offshore oceanic air in September and October. Both city plumes and oceanic air inflows could contribute to ozone enhancements in Shanghai, and the latter are found to lead to 20–30 % increases in urban ozone concentrations based on WRF-Chem simulations.
Chaomin Wang, Bin Yuan, Caihong Wu, Sihang Wang, Jipeng Qi, Baolin Wang, Zelong Wang, Weiwei Hu, Wei Chen, Chenshuo Ye, Wenjie Wang, Yele Sun, Chen Wang, Shan Huang, Wei Song, Xinming Wang, Suxia Yang, Shenyang Zhang, Wanyun Xu, Nan Ma, Zhanyi Zhang, Bin Jiang, Hang Su, Yafang Cheng, Xuemei Wang, and Min Shao
Atmos. Chem. Phys., 20, 14123–14138, https://doi.org/10.5194/acp-20-14123-2020, https://doi.org/10.5194/acp-20-14123-2020, 2020
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We utilized a novel online mass spectrometry method to measure the total concentration of higher alkanes at each carbon number at two different sites in China, allowing us to take into account SOA contributions from all isomers for higher alkanes. We found that higher alkanes account for significant fractions of SOA formation at the two sites. The contributions are comparable to or even higher than single-ring aromatics, the most-recognized SOA precursors in urban air.
Yuli Zhang, Mengchu Tao, Jinqiang Zhang, Yi Liu, Hongbin Chen, Zhaonan Cai, and Paul Konopka
Atmos. Chem. Phys., 20, 13343–13354, https://doi.org/10.5194/acp-20-13343-2020, https://doi.org/10.5194/acp-20-13343-2020, 2020
Henrik Skov, Jens Hjorth, Claus Nordstrøm, Bjarne Jensen, Christel Christoffersen, Maria Bech Poulsen, Jesper Baldtzer Liisberg, David Beddows, Manuel Dall'Osto, and Jesper Heile Christensen
Atmos. Chem. Phys., 20, 13253–13265, https://doi.org/10.5194/acp-20-13253-2020, https://doi.org/10.5194/acp-20-13253-2020, 2020
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Mercury is toxic in all its forms. It bioaccumulates in food webs, is ubiquitous in the atmosphere, and atmospheric transport is an important source for this element in the Arctic. Measurements of gaseous elemental mercury have been carried out at the Villum Research Station at Station Nord in northern Greenland since 1999. The measurements are compared with model results from the Danish Eulerian Hemispheric Model. In this way, the dynamics of mercury are investigated.
Yangang Ren, Bastian Stieger, Gerald Spindler, Benoit Grosselin, Abdelwahid Mellouki, Thomas Tuch, Alfred Wiedensohler, and Hartmut Herrmann
Atmos. Chem. Phys., 20, 13069–13089, https://doi.org/10.5194/acp-20-13069-2020, https://doi.org/10.5194/acp-20-13069-2020, 2020
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We present HONO measurements from the TROPOS research site in Melpitz, Germany. Investigations of HONO sources and sinks revealed the nighttime formation by heterogeneous conversion of NO2 to HONO followed by a significant surface deposition at night. The evaporation of dew was identified as the main HONO source in the morning. In the following, dew measurements with a self-made dew collector were performed to estimate the amount of evaporated HONO from dew in the atmospheric HONO distribution.
David S. McLagan, Geoff W. Stupple, Andrea Darlington, Katherine Hayden, and Alexandra Steffen
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2020-1119, https://doi.org/10.5194/acp-2020-1119, 2020
Revised manuscript accepted for ACP
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An assessment of mercury emissions from a burning boreal forest was made by flying an aircraft through its plume to collect in-situ gas and particulate measurements. Direct data show that in plume gaseous elemental mercury concentrations reach up to 2.4x background for this fire and up to 5.6x when using a correlation with CO data. These unique data are applied to a series of known empirical emissions estimates and used to highlight current uncertainties in the literature.
Chen Dayan, Erick Fredj, Pawel K. Misztal, Maor Gabay, Alex B. Guenther, and Eran Tas
Atmos. Chem. Phys., 20, 12741–12759, https://doi.org/10.5194/acp-20-12741-2020, https://doi.org/10.5194/acp-20-12741-2020, 2020
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We studied the emission of biogenic volatile organic compounds from both marine and terrestrial ecosystems in the Eastern Mediterranean Basin, a global warming hot spot. We focused on isoprene and dimethyl sulfide (DMS), which are well recognized for their effect on climate and strong impact on photochemical pollution by the former. We found high emissions of isoprene and a strong decadal decrease in the emission of DMS which can both be attributed to the strong increase in seawater temperature.
Bettina Hottmann, Sascha Hafermann, Laura Tomsche, Daniel Marno, Monica Martinez, Hartwig Harder, Andrea Pozzer, Marco Neumaier, Andreas Zahn, Birger Bohn, Greta Stratmann, Helmut Ziereis, Jos Lelieveld, and Horst Fischer
Atmos. Chem. Phys., 20, 12655–12673, https://doi.org/10.5194/acp-20-12655-2020, https://doi.org/10.5194/acp-20-12655-2020, 2020
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During OMO we observed enhanced mixing ratios of hydroperoxides (ROOH) in the Asian monsoon anticyclone (AMA) relative to the background. The observed mixing ratios are higher than steady-state calculations and EMAC simulations, especially in the AMA, indicating atmospheric transport of ROOH. Uncertainties in the scavenging efficiencies likely cause deviations from EMAC. Longitudinal gradients indicate a pool of ROOH towards the center of the AMA associated with upwind convection over India.
Ziru Lan, Weili Lin, Weiwei Pu, and Ziqiang Ma
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2020-1047, https://doi.org/10.5194/acp-2020-1047, 2020
Revised manuscript accepted for ACP
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Haze related with particulate matter has been a big problem in eastern China. Ammonia (NH3) plays an important role in secondary particulate matter formation. The variations in NH3 were found that the contributions of NH3 sources on the urban and suburban areas were quite different, although they were under the influence of similar weather systems. The studies help us to understand the NH3 behaviors at a megacity environment.
Ashish Kumar, Vinayak Sinha, Muhammed Shabin, Haseeb Hakkim, Bernard Bonsang, and Valerie Gros
Atmos. Chem. Phys., 20, 12133–12152, https://doi.org/10.5194/acp-20-12133-2020, https://doi.org/10.5194/acp-20-12133-2020, 2020
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Source apportionment studies require information on the chemical fingerprints of pollution sources to correctly quantify source contributions to ambient composition. These chemical fingerprints vary from region to region, depending on fuel composition and combustion conditions, and are poorly constrained over developing regions such as South Asia. This work characterises the chemical fingerprints of urban and agricultural sources using 49 non-methane hydrocarbons and their environmental impacts.
Swaleha Inamdar, Liselotte Tinel, Rosie Chance, Lucy J. Carpenter, Prabhakaran Sabu, Racheal Chacko, Sarat C. Tripathy, Anvita U. Kerkar, Alok K. Sinha, Parli Venkateswaran Bhaskar, Amit Sarkar, Rajdeep Roy, Tomás Sherwen, Carlos Cuevas, Alfonso Saiz-Lopez, Kirpa Ram, and Anoop S. Mahajan
Atmos. Chem. Phys., 20, 12093–12114, https://doi.org/10.5194/acp-20-12093-2020, https://doi.org/10.5194/acp-20-12093-2020, 2020
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Iodine chemistry is generating a lot of interest because of its impacts on the oxidising capacity of the marine boundary and depletion of ozone. However, one of the challenges has been predicting the right levels of iodine in the models, which depend on parameterisations for emissions from the sea surface. This paper discusses the different parameterisations available and compares them with observations, showing that our current knowledge is still insufficient, especially on a regional scale.
Haeyoung Lee, Edward J. Dlugokencky, Jocelyn C. Turnbull, Sepyo Lee, Scott J. Lehman, John B. Miller, Gabrielle Pétron, Jeong-Sik Lim, Gang-Woong Lee, Sang-Sam Lee, and Young-San Park
Atmos. Chem. Phys., 20, 12033–12045, https://doi.org/10.5194/acp-20-12033-2020, https://doi.org/10.5194/acp-20-12033-2020, 2020
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To understand South Korea's CO2 emissions and sinks as well as those of the surrounding region, we used flask-air samples collected for 2 years at Anmyeondo (36.53° N, 126.32° E; 46 m a.s.l.), South Korea, for analysis of observed 14C in atmospheric CO2 as a tracer of fossil fuel CO2 contribution (Cff). Here, we showed our observation result of 14C and Cff. SF6 and CO can be good proxies of Cff in this study, and the ratio of CO to Cff was compared to a bottom-up inventory.
Ying Jiang, Likun Xue, Rongrong Gu, Mengwei Jia, Yingnan Zhang, Liang Wen, Penggang Zheng, Tianshu Chen, Hongyong Li, Ye Shan, Yong Zhao, Zhaoxin Guo, Yujian Bi, Hengde Liu, Aijun Ding, Qingzhu Zhang, and Wenxing Wang
Atmos. Chem. Phys., 20, 12115–12131, https://doi.org/10.5194/acp-20-12115-2020, https://doi.org/10.5194/acp-20-12115-2020, 2020
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We analyzed the characteristics and sources of HONO in the upper boundary layer and lower free troposphere in the North China Plain, based on the field measurements at Mount Tai. Higher-than-expected levels and broad daytime peaks of HONO were observed. Without presence of ground surfaces, aerosol surface plays a key role in the heterogeneous HONO formation at high altitudes. Models without additional HONO sources largely
underestimatedthe oxidation processes in the elevation atmospheres.
Kazuo Osada
Atmos. Chem. Phys., 20, 11941–11954, https://doi.org/10.5194/acp-20-11941-2020, https://doi.org/10.5194/acp-20-11941-2020, 2020
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Various sources and meteorological conditions affect the short-term variation in NH3 concentrations in the urban atmosphere. An analysis of 2 years of hourly data suggests that mist evaporation and stomata exchange of tree leaves after the effects of bird droppings engenders a rapid increase in NH3 concentrations. Emissions from urban tree canopies are a new mode of passing reactive nitrogen that has never before been described as an important source in the literature.
Shona E. Wilde, Pamela A. Dominutti, Stephen J. Andrews, Stephane J.-B. Bauguitte, Ralph R. Burton, Ioana Colfescu, James France, James R. Hopkins, Anna E. Jones, Tom Lachlan-Cope, James D. Lee, Alastair C. Lewis, Stephen D. Mobbs, Alexandra Weiss, Stuart Young, and Ruth M. Purvis
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2020-1099, https://doi.org/10.5194/acp-2020-1099, 2020
Revised manuscript accepted for ACP
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We use airborne measurements to evaluate the speciation of volatile organic compound (VOC) emissions from offshore oil and gas (O&G) installations in the North Sea. The composition of emissions varied across regions associated with either gas, condensate or oil extraction, demonstrating that VOC emissions are not uniform across the whole O&G sector. We compare our results to VOC source profiles in the UK emissions inventory, showing these emissions are not currently fully characterised.
Lubna Dada, Ilona Ylivinkka, Rima Baalbaki, Chang Li, Yishuo Guo, Chao Yan, Lei Yao, Nina Sarnela, Tuija Jokinen, Kaspar R. Daellenbach, Rujing Yin, Chenjuan Deng, Biwu Chu, Tuomo Nieminen, Yonghong Wang, Zhuohui Lin, Roseline C. Thakur, Jenni Kontkanen, Dominik Stolzenburg, Mikko Sipilä, Tareq Hussein, Pauli Paasonen, Federico Bianchi, Imre Salma, Tamás Weidinger, Michael Pikridas, Jean Sciare, Jingkun Jiang, Yongchun Liu, Tuukka Petäjä, Veli-Matti Kerminen, and Markku Kulmala
Atmos. Chem. Phys., 20, 11747–11766, https://doi.org/10.5194/acp-20-11747-2020, https://doi.org/10.5194/acp-20-11747-2020, 2020
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We rely on sulfuric acid measurements in four contrasting environments, Hyytiälä, Finland; Agia Marina, Cyprus; Budapest, Hungary; and Beijing, China, representing semi-pristine boreal forest, rural environment in the Mediterranean area, urban environment, and heavily polluted megacity, respectively, in order to define the sources and sinks of sulfuric acid in these environments and to derive a new sulfuric acid proxy to be utilized in locations and during periods when it is not measured.
Di Liu, Wanqi Sun, Ning Zeng, Pengfei Han, Bo Yao, Zhiqiang Liu, Pucai Wang, Ke Zheng, Han Mei, and Qixiang Cai
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2020-966, https://doi.org/10.5194/acp-2020-966, 2020
Revised manuscript accepted for ACP
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It is difficult to directly observe the COVID-19 signals in CO2 due to the strong weather induced variations. Here we determined the on-road CO2 concentration declines in Beijing using mobile observatory data before (BC), during (DC) and after COVID-19 (AC). We chose trips with the most similar weather, and calculated the enhancement, the difference between on-road and the city
background. We showed a clear on-road CO2 decrease in DC, which are consistent with the emissions reductions in DC.
Wendell W. Walters, Linlin Song, Jiajue Chai, Yunting Fang, Nadia Colombi, and Meredith G. Hastings
Atmos. Chem. Phys., 20, 11551–11567, https://doi.org/10.5194/acp-20-11551-2020, https://doi.org/10.5194/acp-20-11551-2020, 2020
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This article details new field observations of the nitrogen stable isotopic composition of ammonia emitted from vehicles conducted in the US and China. Vehicle emissions of ammonia may be a significant source to urban regions with important human health and environmental implications. Our measurements have indicated a consistent isotopic signature from vehicle ammonia emissions. The nitrogen isotopic composition of ammonia may be a useful tool for tracking vehicle emissions.
Xiaofei Qin, Leiming Zhang, Guochen Wang, Xiaohao Wang, Qingyan Fu, Jian Xu, Hao Li, Jia Chen, Qianbiao Zhao, Yanfen Lin, Juntao Huo, Fengwen Wang, Kan Huang, and Congrui Deng
Atmos. Chem. Phys., 20, 10985–10996, https://doi.org/10.5194/acp-20-10985-2020, https://doi.org/10.5194/acp-20-10985-2020, 2020
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The uncertainties in mercury emissions are much larger from natural sources than anthropogenic sources. A method was developed to quantify the contributions of natural surface emissions to ambient GEM based on PMF modeling. The annual GEM concentration in eastern China showed a decreasing trend from 2015 to 2018, while the relative contribution of natural surface emissions increased significantly from 41 % in 2015 to 57 % in 2018, gradually surpassing those from anthropogenic sources.
Nijing Wang, Achim Edtbauer, Christof Stönner, Andrea Pozzer, Efstratios Bourtsoukidis, Lisa Ernle, Dirk Dienhart, Bettina Hottmann, Horst Fischer, Jan Schuladen, John N. Crowley, Jean-Daniel Paris, Jos Lelieveld, and Jonathan Williams
Atmos. Chem. Phys., 20, 10807–10829, https://doi.org/10.5194/acp-20-10807-2020, https://doi.org/10.5194/acp-20-10807-2020, 2020
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Carbonyl compounds were measured on a ship travelling around the Arabian Peninsula in summer 2017, crossing both highly polluted and extremely clean regions of the marine boundary layer. We investigated the sources and sinks of carbonyls. The results from a global model showed a significant model underestimation for acetaldehyde, a molecule that can influence regional air chemistry. By adding a diurnal oceanic source, the model estimation was highly improved.
Xinghong Cheng, Jianzhong Ma, Junli Jin, Junrang Guo, Yuelin Liu, Jida Peng, Xiaodan Ma, Minglong Qian, Qiang Xia, and Peng Yan
Atmos. Chem. Phys., 20, 10757–10774, https://doi.org/10.5194/acp-20-10757-2020, https://doi.org/10.5194/acp-20-10757-2020, 2020
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We carried out 19 city-circle-around Car MAX-DOAS experiments on the 6th Ring Road of Beijing in Jan, Sep, and Oct 2014. The tropospheric VCDs of NO2 are retrieved and their temporal and spatial distributions are investigated. Then the NOx emission rates in urban Beijing are estimated using the measured NO2 VCDs together with the refined wind fields, NO2-to-NOx ratios, and NO2 lifetimes simulated by the LAPS-WRF-CMAQ model system, and results are compared with the MEIC inventory in 2012.
Jan-Stefan Swartz, Pieter G. van Zyl, Johan P. Beukes, Corinne Galy-Lacaux, Avishkar Ramandh, and Jacobus J. Pienaar
Atmos. Chem. Phys., 20, 10637–10665, https://doi.org/10.5194/acp-20-10637-2020, https://doi.org/10.5194/acp-20-10637-2020, 2020
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Statistical modelling of interdependencies between local, regional and global parameters on long-term trends of atmospheric SO2, NO2 and O2 within proximity of the pollution hotspot in South Africa indicated that changes in meteorological conditions and/or variances in source influences contributed to temporal variability. The impact of increased anthropogenic activities and energy demand was evident, while the El Niño–Southern Oscillation made a significant contribution to O3 levels.
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
Clémence Rose, Matti P. Rissanen, Siddharth Iyer, Jonathan Duplissy, Chao Yan, John B. Nowak, Aurélie Colomb, Régis Dupuy, Xu-Cheng He, Janne Lampilahti, Yee Jun Tham, Daniela Wimmer, Jean-Marc Metzger, Pierre Tulet, Jérôme Brioude, Céline Planche, Markku Kulmala, and Karine Sellegri
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2020-636, https://doi.org/10.5194/acp-2020-636, 2020
Revised manuscript accepted for ACP
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Sulfuric acid (H2SO4) is commonly accepted as a key precursor for atmospheric new particle formation. However, direct measurements of [H2SO4] remain challenging, thus motivating the development of proxies. Using data collected in two different volcanic plumes, we show, in these specific conditions, the good performance of a proxy from the literature and highlight as well the benefit of the newly developed proxies for the prediction of the highest [H2SO4] concentrations.
Johannes Bieser, Hélène Angot, Franz Slemr, and Lynwill Martin
Atmos. Chem. Phys., 20, 10427–10439, https://doi.org/10.5194/acp-20-10427-2020, https://doi.org/10.5194/acp-20-10427-2020, 2020
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We use numerical models to determine the origin of air masses measured for elemental gaseous mercury (GEM) at Cape Point (CPT), South Africa. Our analysis is based on 10 years of hourly GEM measurements at CPT from 2007 to 2016. Based on GEM concentration and the origin of the air mass, we identify source and sink regions at CPT. We find, that the warm Agulhas Current to the south-east is the major Hg source and the continent the major sink.
Nur H. Orak, Matthew Reeder, and Natalie J. Pekney
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2020-833, https://doi.org/10.5194/acp-2020-833, 2020
Revised manuscript accepted for ACP
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In this manuscript, we investigate the effect of unconventional natural gas development activities on local air quality. This is the first study, to our knowledge, to identify the potential source categories of pollutants on well pad through different production stages and to investigate the relative effect of each phase of development. This detailed information about the distribution of pollutants’ sources through a well pad’s life cycle is needed to manage the associated risks from emissions.
Tatiana Drotikova, Aasim M. Ali, Anne Karine Halse, Helena C. Reinardy, and Roland Kallenborn
Atmos. Chem. Phys., 20, 9997–10014, https://doi.org/10.5194/acp-20-9997-2020, https://doi.org/10.5194/acp-20-9997-2020, 2020
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Polycyclic aromatic hydrocarbons (PAHs) are not declining in Arctic air despite reductions in global emissions. We studied PAHs and oxy- and nitro-PAHs in gas and particulate phases of Arctic aerosol, collected in autumn 2018 in Longyearbyen, Svalbard. PAHs were found at comparable levels as at other background Scandinavian and European air sampling stations. Statistical analysis confirmed that a coal-fired power plant and vehicle and marine traffic are the main local contributors of PAHs.
Mengdi Song, Xin Li, Suding Yang, Xuena Yu, Songxiu Zhou, Yiming Yang, Shiyi Chen, Huabin Dong, Keren Liao, Qi Chen, Keding Lu, Ningning Zhang, Junji Cao, Liming Zeng, and Yuanhang Zhang
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2020-704, https://doi.org/10.5194/acp-2020-704, 2020
Revised manuscript accepted for ACP
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Due to their lower diffusion capacities and higher conversion capacities, urban areas in Xi’an experienced severe ozone pollution in the summer, and the concentration and proportion of oxygenated VOCs increased significantly during ozone pollution days. Xi'an has a strong local emission source of VOCs, and vehicle exhaust was the primary VOC source. In addition, alkenes, aromatics, and OVOCs played a dominant role in secondary transformations.
Liwei Wang, Jay G. Slowik, Nidhi Tripathi, Deepika Bhattu, Pragati Rai, Varun Kumar, Pawan Vats, Rangu Satish, Urs Baltensperger, Dilip Ganguly, Neeraj Rastogi, Lokesh K. Sahu, Sachchida N. Tripathi, and André S. H. Prévôt
Atmos. Chem. Phys., 20, 9753–9770, https://doi.org/10.5194/acp-20-9753-2020, https://doi.org/10.5194/acp-20-9753-2020, 2020
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Angelbratt, J., Mellqvist, J., Simpson, D., Jonson, J. E., Blumenstock, T., Borsdorff, T., Duchatelet, P., Forster, F., Hase, F., Mahieu, E., De Mazière, M., Notholt, J., Petersen, A. K., Raffalski, U., Servais, C., Sussmann, R., Warneke, T., and Vigouroux, C.: Carbon monoxide (CO) and ethane (C2H6) trends from ground-based solar FTIR measurements at six European stations, comparison and sensitivity analysis with the EMEP model, Atmos. Chem. Phys., 11, 9253–9269, https://doi.org/10.5194/acp-11-9253-2011, 2011.
Barret, B., Sauvage, B., Bennouna, Y., and Le Flochmoen, E.: Upper-tropospheric CO and O3 budget during the Asian summer monsoon, Atmos. Chem. Phys., 16, 9129–9147, https://doi.org/10.5194/acp-16-9129-2016, 2016.
Boothe, A. C. and Homeyer, C. R.: Global large-scale stratosphere–troposphere exchange in modern reanalyses, Atmos. Chem. Phys., 17, 5537–5559, https://doi.org/10.5194/acp-17-5537-2017, 2017.
Bremer, H., Kar, J., Drummond, J. R., Nichitu, F., Zou, J., Liu, J., Gille, J. C., Deeter, M. N., Francis, G., Ziskin, D., and Warner, J.: Spatial and temporal variation of MOPITT CO in Africa and South America: A comparison with SHADOZ ozone and MODIS aerosol, J. Geophys. Res.-Atmos., 109, 2156–2202, https://doi.org/10.1029/2003JD004234, 2004.
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Special issue
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.
Measurements of ozone and carbon monoxide were performed during 1994–2013 around the tropopause...
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