Articles | Volume 19, issue 17
https://doi.org/10.5194/acp-19-11401-2019
© Author(s) 2019. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Special issue:
https://doi.org/10.5194/acp-19-11401-2019
© Author(s) 2019. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
10 Sep 2019
Research article |
| 10 Sep 2019
| 10 Sep 2019
Local air pollution from oil rig emissions observed during the airborne DACCIWA campaign
Vanessa Brocchi
Laboratoire de Physique et Chimie de l'Environnement et de l'Espace
(LPC2E), CNRS, Université Orléans, CNES, 45071 Orléans CEDEX
2, France
Gisèle Krysztofiak
CORRESPONDING AUTHOR
Laboratoire de Physique et Chimie de l'Environnement et de l'Espace
(LPC2E), CNRS, Université Orléans, CNES, 45071 Orléans CEDEX
2, France
Adrien Deroubaix
LMD and LATMOS, École Polytechnique, Université Paris-Saclay,
ENS, IPSL Research University, Sorbonne Université, UPMC Univ Paris 06,
CNRS, Palaiseau, France
Greta Stratmann
Institut für Physik der Atmosphäre, Deutsches Zentrum für
Luft und Raumfahrt, Oberpfaffenhofen, Germany
Daniel Sauer
Institut für Physik der Atmosphäre, Deutsches Zentrum für
Luft und Raumfahrt, Oberpfaffenhofen, Germany
Hans Schlager
Institut für Physik der Atmosphäre, Deutsches Zentrum für
Luft und Raumfahrt, Oberpfaffenhofen, Germany
Konrad Deetz
Karlsruhe Institute of Technology, Institute of Meteorology and
Climate Research, Karlsruhe, Germany
Guillaume Dayma
Institut de Combustion Aérothermique Réactivité et
Environnement (ICARE), CNRS, 45071 Orléans CEDEX 2, France
Claude Robert
Laboratoire de Physique et Chimie de l'Environnement et de l'Espace
(LPC2E), CNRS, Université Orléans, CNES, 45071 Orléans CEDEX
2, France
Stéphane Chevrier
Laboratoire de Physique et Chimie de l'Environnement et de l'Espace
(LPC2E), CNRS, Université Orléans, CNES, 45071 Orléans CEDEX
2, France
Valéry Catoire
Laboratoire de Physique et Chimie de l'Environnement et de l'Espace
(LPC2E), CNRS, Université Orléans, CNES, 45071 Orléans CEDEX
2, France
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Oliver Appel, Franziska Köllner, Antonis Dragoneas, Andreas Hünig, Sergej Molleker, Hans Schlager, Christoph Mahnke, Ralf Weigel, Max Port, Christiane Schulz, Frank Drewnick, Bärbel Vogel, Fred Stroh, and Stephan Borrmann
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Simon F. Reifenberg, Anna Martin, Matthias Kohl, Sara Bacer, Zaneta Hamryszczak, Ivan Tadic, Lenard Röder, Daniel J. Crowley, Horst Fischer, Katharina Kaiser, Johannes Schneider, Raphael Dörich, John N. Crowley, Laura Tomsche, Andreas Marsing, Christiane Voigt, Andreas Zahn, Christopher Pöhlker, Bruna A. Holanda, Ovid Krüger, Ulrich Pöschl, Mira Pöhlker, Patrick Jöckel, Marcel Dorf, Ulrich Schumann, Jonathan Williams, Birger Bohn, Joachim Curtius, Hardwig Harder, Hans Schlager, Jos Lelieveld, and Andrea Pozzer
Atmos. Chem. Phys., 22, 10901–10917, https://doi.org/10.5194/acp-22-10901-2022, https://doi.org/10.5194/acp-22-10901-2022, 2022
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M. Dolores Andrés Hernández, Andreas Hilboll, Helmut Ziereis, Eric Förster, Ovid O. Krüger, Katharina Kaiser, Johannes Schneider, Francesca Barnaba, Mihalis Vrekoussis, Jörg Schmidt, Heidi Huntrieser, Anne-Marlene Blechschmidt, Midhun George, Vladyslav Nenakhov, Theresa Harlass, Bruna A. Holanda, Jennifer Wolf, Lisa Eirenschmalz, Marc Krebsbach, Mira L. Pöhlker, Anna B. Kalisz Hedegaard, Linlu Mei, Klaus Pfeilsticker, Yangzhuoran Liu, Ralf Koppmann, Hans Schlager, Birger Bohn, Ulrich Schumann, Andreas Richter, Benjamin Schreiner, Daniel Sauer, Robert Baumann, Mariano Mertens, Patrick Jöckel, Markus Kilian, Greta Stratmann, Christopher Pöhlker, Monica Campanelli, Marco Pandolfi, Michael Sicard, José L. Gómez-Amo, Manuel Pujadas, Katja Bigge, Flora Kluge, Anja Schwarz, Nikos Daskalakis, David Walter, Andreas Zahn, Ulrich Pöschl, Harald Bönisch, Stephan Borrmann, Ulrich Platt, and John P. Burrows
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EMeRGe provides a unique set of in situ and remote sensing airborne measurements of trace gases and aerosol particles along selected flight routes in the lower troposphere over Europe. The interpretation uses also complementary collocated ground-based and satellite measurements. The collected data help to improve the current understanding of the complex spatial distribution of trace gases and aerosol particles resulting from mixing, transport, and transformation of pollution plumes over Europe.
Adrien Deroubaix, Laurent Menut, Cyrille Flamant, Peter Knippertz, Andreas H. Fink, Anneke Batenburg, Joel Brito, Cyrielle Denjean, Cheikh Dione, Régis Dupuy, Valerian Hahn, Norbert Kalthoff, Fabienne Lohou, Alfons Schwarzenboeck, Guillaume Siour, Paolo Tuccella, and Christiane Voigt
Atmos. Chem. Phys., 22, 3251–3273, https://doi.org/10.5194/acp-22-3251-2022, https://doi.org/10.5194/acp-22-3251-2022, 2022
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During the summer monsoon in West Africa, pollutants emitted in urbanized areas modify cloud cover and precipitation patterns. We analyze these patterns with the WRF-CHIMERE model, integrating the effects of aerosols on meteorology, based on the numerous observations provided by the Dynamics-Aerosol-Climate-Interactions campaign. This study adds evidence to recent findings that increased pollution levels in West Africa delay the breakup time of low-level clouds and reduce precipitation.
Chaoyang Xue, Can Ye, Jörg Kleffmann, Chenglong Zhang, Valéry Catoire, Fengxia Bao, Abdelwahid Mellouki, Likun Xue, Jianmin Chen, Keding Lu, Yong Zhao, Hengde Liu, Zhaoxin Guo, and Yujing Mu
Atmos. Chem. Phys., 22, 3149–3167, https://doi.org/10.5194/acp-22-3149-2022, https://doi.org/10.5194/acp-22-3149-2022, 2022
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Summertime measurements of nitrous acid (HONO) and related parameters were conducted at the foot and the summit of Mt. Tai (1534 m above sea level). We proposed a rapid vertical air mass exchange between the foot and the summit level, which enhances the role of HONO in the oxidizing capacity of the upper boundary layer. Kinetics for aerosol-derived HONO sources were constrained. HONO formation from different paths was quantified and discussed.
Chaoyang Xue, Can Ye, Jörg Kleffmann, Wenjin Zhang, Xiaowei He, Pengfei Liu, Chenglong Zhang, Xiaoxi Zhao, Chengtang Liu, Zhuobiao Ma, Junfeng Liu, Jinhe Wang, Keding Lu, Valéry Catoire, Abdelwahid Mellouki, and Yujing Mu
Atmos. Chem. Phys., 22, 1035–1057, https://doi.org/10.5194/acp-22-1035-2022, https://doi.org/10.5194/acp-22-1035-2022, 2022
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Nitrous acid (HONO) and related parameters were measured at the foot and the summit of Mt. Tai in the summer of 2018. Based on measurements at the foot station, we utilized a box model to explore the roles of different sources in the HONO budget. We also studied radical chemistry in this high-ozone region.
Ramon Campos Braga, Barbara Ervens, Daniel Rosenfeld, Meinrat O. Andreae, Jan-David Förster, Daniel Fütterer, Lianet Hernández Pardo, Bruna A. Holanda, Tina Jurkat-Witschas, Ovid O. Krüger, Oliver Lauer, Luiz A. T. Machado, Christopher Pöhlker, Daniel Sauer, Christiane Voigt, Adrian Walser, Manfred Wendisch, Ulrich Pöschl, and Mira L. Pöhlker
Atmos. Chem. Phys., 21, 17513–17528, https://doi.org/10.5194/acp-21-17513-2021, https://doi.org/10.5194/acp-21-17513-2021, 2021
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Interactions of aerosol particles with clouds represent a large uncertainty in estimates of climate change. Properties of aerosol particles control their ability to act as cloud condensation nuclei. Using aerosol measurements in the Amazon, we performed model studies to compare predicted and measured cloud droplet number concentrations at cloud bases. Our results confirm previous estimates of particle hygroscopicity in this region.
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., 21, 16955–16984, https://doi.org/10.5194/acp-21-16955-2021, https://doi.org/10.5194/acp-21-16955-2021, 2021
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Bromoform is a stratospheric ozone-depleting gas released by seaweed and plankton 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.
Tiziana Bräuer, Christiane Voigt, Daniel Sauer, Stefan Kaufmann, Valerian Hahn, Monika Scheibe, Hans Schlager, Felix Huber, Patrick Le Clercq, Richard H. Moore, and Bruce E. Anderson
Atmos. Chem. Phys., 21, 16817–16826, https://doi.org/10.5194/acp-21-16817-2021, https://doi.org/10.5194/acp-21-16817-2021, 2021
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Over half of aviation climate impact is caused by contrails. Biofuels can reduce the ice crystal numbers in contrails and mitigate the climate impact. The experiment ECLIF II/NDMAX in 2018 assessed the effects of biofuels on contrails and aviation emissions. The NASA DC-8 aircraft performed measurements inside the contrail of the DLR A320. One reference fuel and two blends of the biofuel HEFA and kerosene are analysed. We find a max reduction of contrail ice numbers through biofuel use of 40 %.
Yu-Wen Chen, Yi-Chun Chen, Charles C.-K. Chou, Hui-Ming Hung, Shih-Yu Chang, Lisa Eirenschmalz, Michael Lichtenstern, Helmut Ziereis, Hans Schlager, Greta Stratmann, Katharina Kaiser, Johannes Schneider, Stephan Borrmann, Florian Obersteiner, Eric Förster, Andreas Zahn, Wei-Nai Chen, Po-Hsiung Lin, Shuenn-Chin Chang, Maria Dolores Andrés Hernández, Pao-Kuan Wang, and John P. Burrows
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2021-788, https://doi.org/10.5194/acp-2021-788, 2021
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By presenting an approach using EMeRGe-Asia airborne field measurements and surface observations, this study shows that the fraction of OH reactivity due to SO2-OH reaction has a significant correlation with the sulfate concentration. Approximately 30 % of sulfate is produced by SO2-OH reaction. Our results underline the importance of SO2-OH gas-phase oxidation in sulfate formation, and demonstrate that the method can be applied to other regions and under different meteorological conditions.
Thierno Doumbia, Claire Granier, Nellie Elguindi, Idir Bouarar, Sabine Darras, Guy Brasseur, Benjamin Gaubert, Yiming Liu, Xiaoqin Shi, Trissevgeni Stavrakou, Simone Tilmes, Forrest Lacey, Adrien Deroubaix, and Tao Wang
Earth Syst. Sci. Data, 13, 4191–4206, https://doi.org/10.5194/essd-13-4191-2021, https://doi.org/10.5194/essd-13-4191-2021, 2021
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Most countries around the world have implemented control measures to combat the spread of the COVID-19 pandemic, resulting in significant changes in economic and personal activities. We developed the CONFORM (COvid-19 adjustmeNt Factors fOR eMissions) dataset to account for changes in emissions during lockdowns. This dataset was created with the intention of being directly applicable to existing global and regional inventories used in chemical transport models.
Maxi Boettcher, Andreas Schäfler, Michael Sprenger, Harald Sodemann, Stefan Kaufmann, Christiane Voigt, Hans Schlager, Donato Summa, Paolo Di Girolamo, Daniele Nerini, Urs Germann, and Heini Wernli
Atmos. Chem. Phys., 21, 5477–5498, https://doi.org/10.5194/acp-21-5477-2021, https://doi.org/10.5194/acp-21-5477-2021, 2021
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Warm conveyor belts (WCBs) are important airstreams in extratropical cyclones, often leading to the formation of intense precipitation. We present a case study that involves aircraft, lidar and radar observations of water and clouds in a WCB ascending from western Europe across the Alps towards the Baltic Sea during the field campaigns HyMeX and T-NAWDEX-Falcon in October 2012. A probabilistic trajectory measure and an airborne tracer experiment were used to confirm the long pathway of the WCB.
Joan Stude, Heinfried Aufmhoff, Hans Schlager, Markus Rapp, Frank Arnold, and Boris Strelnikov
Atmos. Meas. Tech., 14, 983–993, https://doi.org/10.5194/amt-14-983-2021, https://doi.org/10.5194/amt-14-983-2021, 2021
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In this paper we describe the instrument ROMARA and show data from the first flight on a research rocket.
On the way through the atmosphere, the instrument detects positive and negative, natural occurring ions before returning back to ground.
ROMARA was successfully launched together with other instruments into a special radar echo.
We detected typical, light ions of positive and negative charge and heavy negative ions, but no heavy positive ions.
Johannes Schneider, Ralf Weigel, Thomas Klimach, Antonis Dragoneas, Oliver Appel, Andreas Hünig, Sergej Molleker, Franziska Köllner, Hans-Christian Clemen, Oliver Eppers, Peter Hoppe, Peter Hoor, Christoph Mahnke, Martina Krämer, Christian Rolf, Jens-Uwe Grooß, Andreas Zahn, Florian Obersteiner, Fabrizio Ravegnani, Alexey Ulanovsky, Hans Schlager, Monika Scheibe, Glenn S. Diskin, Joshua P. DiGangi, John B. Nowak, Martin Zöger, and Stephan Borrmann
Atmos. Chem. Phys., 21, 989–1013, https://doi.org/10.5194/acp-21-989-2021, https://doi.org/10.5194/acp-21-989-2021, 2021
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During five aircraft missions, we detected aerosol particles containing meteoric material in the lower stratosphere. The stratospheric measurements span a latitude range from 15 to 68° N, and we find that at potential temperature levels of more than 40 K above the tropopause; particles containing meteoric material occur at similar abundance fractions across latitudes and seasons. We conclude that meteoric material is efficiently distributed between high and low latitudes by isentropic mixing.
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.
Flora Kluge, Tilman Hüneke, Matthias Knecht, Michael Lichtenstern, Meike Rotermund, Hans Schlager, Benjamin Schreiner, and Klaus Pfeilsticker
Atmos. Chem. Phys., 20, 12363–12389, https://doi.org/10.5194/acp-20-12363-2020, https://doi.org/10.5194/acp-20-12363-2020, 2020
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The presented study reports on airborne measurements of formaldehyde, glyoxal, methylglyoxal, and CO over the Amazon basin and lays a special focus on the influence of biomass burning emissions on the atmospheric profiles of these carbonyl compounds within the planetary boundary layer as well as in the free and upper troposphere.
Hirofumi Ohyama, Isamu Morino, Voltaire A. Velazco, Theresa Klausner, Gerry Bagtasa, Matthäus Kiel, Matthias Frey, Akihiro Hori, Osamu Uchino, Tsuneo Matsunaga, Nicholas M. Deutscher, Joshua P. DiGangi, Yonghoon Choi, Glenn S. Diskin, Sally E. Pusede, Alina Fiehn, Anke Roiger, Michael Lichtenstern, Hans Schlager, Pao K. Wang, Charles C.-K. Chou, Maria Dolores Andrés-Hernández, and John P. Burrows
Atmos. Meas. Tech., 13, 5149–5163, https://doi.org/10.5194/amt-13-5149-2020, https://doi.org/10.5194/amt-13-5149-2020, 2020
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Column-averaged dry-air mole fractions of CO2 and CH4 measured by a solar viewing portable Fourier transform spectrometer (EM27/SUN) were validated with in situ profile data obtained during the transfer flights of two aircraft campaigns. Atmospheric dynamical properties based on ERA5 and WRF-Chem were used as criteria for selecting the best aircraft profiles for the validation. The resulting air-mass-independent correction factors for the EM27/SUN data were 0.9878 for CO2 and 0.9829 for CH4.
Christof G. Beer, Johannes Hendricks, Mattia Righi, Bernd Heinold, Ina Tegen, Silke Groß, Daniel Sauer, Adrian Walser, and Bernadett Weinzierl
Geosci. Model Dev., 13, 4287–4303, https://doi.org/10.5194/gmd-13-4287-2020, https://doi.org/10.5194/gmd-13-4287-2020, 2020
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Mineral dust aerosol plays an important role in the climate system. Previously, dust emissions have often been represented in global models by prescribed monthly-mean emission fields representative of a specific year. We now apply an online calculation of wind-driven dust emissions. This results in an improved agreement with observations, due to a better representation of the highly variable dust emissions. Increasing the model resolution led to an additional performance gain.
Barbara Altstädter, Konrad Deetz, Bernhard Vogel, Karmen Babić, Cheikh Dione, Federica Pacifico, Corinne Jambert, Friederike Ebus, Konrad Bärfuss, Falk Pätzold, Astrid Lampert, Bianca Adler, Norbert Kalthoff, and Fabienne Lohou
Atmos. Chem. Phys., 20, 7911–7928, https://doi.org/10.5194/acp-20-7911-2020, https://doi.org/10.5194/acp-20-7911-2020, 2020
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We present the high vertical variability of the black carbon (BC) mass concentration measured with the unmanned aerial system ALADINA during the field experiment of DACCIWA. The COSMO-ART model output was applied for the campaign period and is compared with the observational BC data during a case study on 14–15 July 2016. Enhanced BC concentrations were related to transport processes to the measurement site by maritime inflow and not to local emissions as initially expected.
Bruna A. Holanda, Mira L. Pöhlker, David Walter, Jorge Saturno, Matthias Sörgel, Jeannine Ditas, Florian Ditas, Christiane Schulz, Marco Aurélio Franco, Qiaoqiao Wang, Tobias Donth, Paulo Artaxo, Henrique M. J. Barbosa, Stephan Borrmann, Ramon Braga, Joel Brito, Yafang Cheng, Maximilian Dollner, Johannes W. Kaiser, Thomas Klimach, Christoph Knote, Ovid O. Krüger, Daniel Fütterer, Jošt V. Lavrič, Nan Ma, Luiz A. T. Machado, Jing Ming, Fernando G. Morais, Hauke Paulsen, Daniel Sauer, Hans Schlager, Johannes Schneider, Hang Su, Bernadett Weinzierl, Adrian Walser, Manfred Wendisch, Helmut Ziereis, Martin Zöger, Ulrich Pöschl, Meinrat O. Andreae, and Christopher Pöhlker
Atmos. Chem. Phys., 20, 4757–4785, https://doi.org/10.5194/acp-20-4757-2020, https://doi.org/10.5194/acp-20-4757-2020, 2020
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Biomass burning smoke from African savanna and grassland is transported across the South Atlantic Ocean in defined layers within the free troposphere. The combination of in situ aircraft and ground-based measurements aided by satellite observations showed that these layers are transported into the Amazon Basin during the early dry season. The influx of aged smoke, enriched in black carbon and cloud condensation nuclei, has important implications for the Amazonian aerosol and cloud cycling.
Fan Mei, Jian Wang, Jennifer M. Comstock, Ralf Weigel, Martina Krämer, Christoph Mahnke, John E. Shilling, Johannes Schneider, Christiane Schulz, Charles N. Long, Manfred Wendisch, Luiz A. T. Machado, Beat Schmid, Trismono Krisna, Mikhail Pekour, John Hubbe, Andreas Giez, Bernadett Weinzierl, Martin Zoeger, Mira L. Pöhlker, Hans Schlager, Micael A. Cecchini, Meinrat O. Andreae, Scot T. Martin, Suzane S. de Sá, Jiwen Fan, Jason Tomlinson, Stephen Springston, Ulrich Pöschl, Paulo Artaxo, Christopher Pöhlker, Thomas Klimach, Andreas Minikin, Armin Afchine, and Stephan Borrmann
Atmos. Meas. Tech., 13, 661–684, https://doi.org/10.5194/amt-13-661-2020, https://doi.org/10.5194/amt-13-661-2020, 2020
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In 2014, the US DOE G1 aircraft and the German HALO aircraft overflew the Amazon basin to study how aerosols influence cloud cycles under a clean condition and around a tropical megacity. This paper describes how to meaningfully compare similar measurements from two research aircraft and identify the potential measurement issue. We also discuss the uncertainty range for each measurement for further usage in model evaluation and satellite data validation.
Sophie L. Haslett, Jonathan W. Taylor, Mathew Evans, Eleanor Morris, Bernhard Vogel, Alima Dajuma, Joel Brito, Anneke M. Batenburg, Stephan Borrmann, Johannes Schneider, Christiane Schulz, Cyrielle Denjean, Thierry Bourrianne, Peter Knippertz, Régis Dupuy, Alfons Schwarzenböck, Daniel Sauer, Cyrille Flamant, James Dorsey, Ian Crawford, and Hugh Coe
Atmos. Chem. Phys., 19, 15217–15234, https://doi.org/10.5194/acp-19-15217-2019, https://doi.org/10.5194/acp-19-15217-2019, 2019
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Three aircraft datasets from the DACCIWA campaign in summer 2016 are used here to show there is a background mass of pollution present in the lower atmosphere in southern West Africa. We suggest that this likely comes from biomass burning in central and southern Africa, which has been carried into the region over the Atlantic Ocean. This would have a negative health impact on populations living near the coast and may alter the impact of growing city emissions on cloud formation and the monsoon.
Laurent Menut, Paolo Tuccella, Cyrille Flamant, Adrien Deroubaix, and Marco Gaetani
Atmos. Chem. Phys., 19, 14657–14676, https://doi.org/10.5194/acp-19-14657-2019, https://doi.org/10.5194/acp-19-14657-2019, 2019
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Aerosol direct and indirect effects are studied over west Africa in the summer of 2016 using the coupled WRF-CHIMERE regional model including aerosol–cloud interaction parameterization. Sensitivity experiments are designed to gain insights into the impact of the aerosols dominating the atmospheric composition in southern west Africa. It is shown that the decrease of anthropogenic emissions along the coast has an impact on the mineral dust load over west Africa by increasing their emissions.
Moritz Haarig, Adrian Walser, Albert Ansmann, Maximilian Dollner, Dietrich Althausen, Daniel Sauer, David Farrell, and Bernadett Weinzierl
Atmos. Chem. Phys., 19, 13773–13788, https://doi.org/10.5194/acp-19-13773-2019, https://doi.org/10.5194/acp-19-13773-2019, 2019
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Aerosol particles are necessary in forming a cloud droplet. In order to improve studies of cloud formation, the aerosol load and type below a cloud has to be measured without disturbing the cloud. The lidar is a perfect tool for this purpose, as it provides a vertical profile of the aerosol particles from the ground. We validated the lidar retrieval of cloud-relevant aerosol properties like particle number concentrations with airborne in situ measurements in the Saharan Air Layer at Barbados.
Jonathan W. Taylor, Sophie L. Haslett, Keith Bower, Michael Flynn, Ian Crawford, James Dorsey, Tom Choularton, Paul J. Connolly, Valerian Hahn, Christiane Voigt, Daniel Sauer, Régis Dupuy, Joel Brito, Alfons Schwarzenboeck, Thierry Bourriane, Cyrielle Denjean, Phil Rosenberg, Cyrille Flamant, James D. Lee, Adam R. Vaughan, Peter G. Hill, Barbara Brooks, Valéry Catoire, Peter Knippertz, and Hugh Coe
Atmos. Chem. Phys., 19, 8503–8522, https://doi.org/10.5194/acp-19-8503-2019, https://doi.org/10.5194/acp-19-8503-2019, 2019
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Low-level clouds cover a wide area of southern West Africa (SWA) and play an important role in the region's climate, reflecting sunlight away from the surface. We performed aircraft measurements of aerosols and clouds over SWA during the 2016 summer monsoon and found pollution, and polluted clouds, across the whole region. Smoke from biomass burning in Central Africa is transported to West Africa, causing a polluted background which limits the effect of local pollution on cloud properties.
Sophie L. Haslett, Jonathan W. Taylor, Konrad Deetz, Bernhard Vogel, Karmen Babić, Norbert Kalthoff, Andreas Wieser, Cheikh Dione, Fabienne Lohou, Joel Brito, Régis Dupuy, Alfons Schwarzenboeck, Paul Zieger, and Hugh Coe
Atmos. Chem. Phys., 19, 1505–1520, https://doi.org/10.5194/acp-19-1505-2019, https://doi.org/10.5194/acp-19-1505-2019, 2019
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As the population in West Africa grows and air pollution increases, it is becoming ever more important to understand the effects of this pollution on the climate and on health. Aerosol particles can grow by absorbing water from the air around them. This paper shows that during the monsoon season, aerosol particles in the region are likely to grow significantly because of the high moisture in the air. This means that climate effects from increasing pollution will be enhanced.
J. Christopher Kaiser, Johannes Hendricks, Mattia Righi, Patrick Jöckel, Holger Tost, Konrad Kandler, Bernadett Weinzierl, Daniel Sauer, Katharina Heimerl, Joshua P. Schwarz, Anne E. Perring, and Thomas Popp
Geosci. Model Dev., 12, 541–579, https://doi.org/10.5194/gmd-12-541-2019, https://doi.org/10.5194/gmd-12-541-2019, 2019
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The implementation of the aerosol microphysics submodel MADE3 into the global atmospheric chemistry model EMAC is described and evaluated against an extensive pool of observational data, focusing on aerosol mass and number concentrations, size distributions, composition, and optical properties. EMAC (MADE3) is able to reproduce main aerosol properties reasonably well, in line with the performance of other global aerosol models.
Adrien Deroubaix, Laurent Menut, Cyrille Flamant, Joel Brito, Cyrielle Denjean, Volker Dreiling, Andreas Fink, Corinne Jambert, Norbert Kalthoff, Peter Knippertz, Russ Ladkin, Sylvain Mailler, Marlon Maranan, Federica Pacifico, Bruno Piguet, Guillaume Siour, and Solène Turquety
Atmos. Chem. Phys., 19, 473–497, https://doi.org/10.5194/acp-19-473-2019, https://doi.org/10.5194/acp-19-473-2019, 2019
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This article presents a detailed analysis of anthropogenic and biomass burning pollutants over the Gulf of Guinea coastal region, using observations from the DACCIWA field campaign and modeling. The novelty is that we focus on how these two pollution sources are mixed and transported further inland. We show that during the day pollutants are accumulated along the coastline and transported northward as soon as the daytime convection in the atmospheric boundary layer ceases (16:00 UTC).
Christiane Schulz, Johannes Schneider, Bruna Amorim Holanda, Oliver Appel, Anja Costa, Suzane S. de Sá, Volker Dreiling, Daniel Fütterer, Tina Jurkat-Witschas, Thomas Klimach, Christoph Knote, Martina Krämer, Scot T. Martin, Stephan Mertes, Mira L. Pöhlker, Daniel Sauer, Christiane Voigt, Adrian Walser, Bernadett Weinzierl, Helmut Ziereis, Martin Zöger, Meinrat O. Andreae, Paulo Artaxo, Luiz A. T. Machado, Ulrich Pöschl, Manfred Wendisch, and Stephan Borrmann
Atmos. Chem. Phys., 18, 14979–15001, https://doi.org/10.5194/acp-18-14979-2018, https://doi.org/10.5194/acp-18-14979-2018, 2018
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Aerosol chemical composition measurements in the tropical upper troposphere over the Amazon region show that 78 % of the aerosol in the upper troposphere consists of organic matter. Up to 20 % of the organic aerosol can be attributed to isoprene epoxydiol secondary organic aerosol (IEPOX-SOA). Furthermore, organic nitrates were identified, suggesting a connection to the IEPOX-SOA formation.
Konrad Deetz, Heike Vogel, Sophie Haslett, Peter Knippertz, Hugh Coe, and Bernhard Vogel
Atmos. Chem. Phys., 18, 14271–14295, https://doi.org/10.5194/acp-18-14271-2018, https://doi.org/10.5194/acp-18-14271-2018, 2018
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Water uptake can significantly increase the size and therefore alters the optical properties of aerosols. Our model study reveals that the high moisture and aerosol burden in the southern West African monsoon
layer makes it favorable to quantify properties that determine the aerosol liquid water content and its impact on the aerosol optical depth and radiative transfer. Especially in moist tropical environments the relative humidity impact on AOD has to be considered in atmospheric models.
Cyrille Flamant, Adrien Deroubaix, Patrick Chazette, Joel Brito, Marco Gaetani, Peter Knippertz, Andreas H. Fink, Gaëlle de Coetlogon, Laurent Menut, Aurélie Colomb, Cyrielle Denjean, Rémi Meynadier, Philip Rosenberg, Regis Dupuy, Pamela Dominutti, Jonathan Duplissy, Thierry Bourrianne, Alfons Schwarzenboeck, Michel Ramonet, and Julien Totems
Atmos. Chem. Phys., 18, 12363–12389, https://doi.org/10.5194/acp-18-12363-2018, https://doi.org/10.5194/acp-18-12363-2018, 2018
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This work sheds light on the complex mechanisms by which coastal shallow circulations distribute atmospheric pollutants over the densely populated southern West African region. Pollutants of concern are anthropogenic emissions from coastal cities, as well as biomass burning aerosol and dust associated with long-range transport. The complex vertical distribution of aerosols over coastal southern West Africa is investigated using airborne observations and numerical simulations.
Aurélien Chauvigné, Olivier Jourdan, Alfons Schwarzenboeck, Christophe Gourbeyre, Jean François Gayet, Christiane Voigt, Hans Schlager, Stefan Kaufmann, Stephan Borrmann, Sergej Molleker, Andreas Minikin, Tina Jurkat, and Ulrich Schumann
Atmos. Chem. Phys., 18, 9803–9822, https://doi.org/10.5194/acp-18-9803-2018, https://doi.org/10.5194/acp-18-9803-2018, 2018
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This paper demonstrates a new form of statistical analysis of contrail to cirrus evolution. The authors show well-separated analyses of the different stages of the contrail's evolution, which allows us to study their optical, microphysical, and chemical properties. These results could be used to develop representative parameterizations of the scattering and geometrical properties of the ice crystals’ shapes and sizes, observed in the visible wavelength range.
Konrad Deetz, Heike Vogel, Peter Knippertz, Bianca Adler, Jonathan Taylor, Hugh Coe, Keith Bower, Sophie Haslett, Michael Flynn, James Dorsey, Ian Crawford, Christoph Kottmeier, and Bernhard Vogel
Atmos. Chem. Phys., 18, 9767–9788, https://doi.org/10.5194/acp-18-9767-2018, https://doi.org/10.5194/acp-18-9767-2018, 2018
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Highly resolved process study simulations for 2–3 July are conducted with COSMO-ART to assess the aerosol direct and indirect effect on meteorological conditions over southern West Africa. The meteorological phenomena of Atlantic inflow and stratus-to-cumulus transition are identified as highly susceptible to the aerosol direct effect, leading to a spatial shift of the Atlantic inflow front and a temporal shift of the stratus-to-cumulus transition with changes in the aerosol amount.
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.
Klaus-Dirk Gottschaldt, Hans Schlager, Robert Baumann, Duy Sinh Cai, Veronika Eyring, Phoebe Graf, Volker Grewe, Patrick Jöckel, Tina Jurkat-Witschas, Christiane Voigt, Andreas Zahn, and Helmut Ziereis
Atmos. Chem. Phys., 18, 5655–5675, https://doi.org/10.5194/acp-18-5655-2018, https://doi.org/10.5194/acp-18-5655-2018, 2018
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This study places aircraft trace gas measurements from within the Asian summer monsoon anticyclone into the context of regional, intra- and interannual variability. We find that the processes reflected in the measurements are present throughout multiple simulated monsoon seasons. Dynamical instabilities, photochemical ozone production, lightning and entrainments from the lower troposphere and from the tropopause region determine the distinct composition of the anticyclone and its outflow.
Laurent Menut, Cyrille Flamant, Solène Turquety, Adrien Deroubaix, Patrick Chazette, and Rémi Meynadier
Atmos. Chem. Phys., 18, 2687–2707, https://doi.org/10.5194/acp-18-2687-2018, https://doi.org/10.5194/acp-18-2687-2018, 2018
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During the DACCIWA project, the tropospheric chemical composition in large cities along the Gulf of Guinea is modelled using WRF and CHIMERE, with and without biomass burning emissions. The difference shows the net impact of fires on air quality in Lagos and Abidjan.
Meinrat O. Andreae, Armin Afchine, Rachel Albrecht, Bruna Amorim Holanda, Paulo Artaxo, Henrique M. J. Barbosa, Stephan Borrmann, Micael A. Cecchini, Anja Costa, Maximilian Dollner, Daniel Fütterer, Emma Järvinen, Tina Jurkat, Thomas Klimach, Tobias Konemann, Christoph Knote, Martina Krämer, Trismono Krisna, Luiz A. T. Machado, Stephan Mertes, Andreas Minikin, Christopher Pöhlker, Mira L. Pöhlker, Ulrich Pöschl, Daniel Rosenfeld, Daniel Sauer, Hans Schlager, Martin Schnaiter, Johannes Schneider, Christiane Schulz, Antonio Spanu, Vinicius B. Sperling, Christiane Voigt, Adrian Walser, Jian Wang, Bernadett Weinzierl, Manfred Wendisch, and Helmut Ziereis
Atmos. Chem. Phys., 18, 921–961, https://doi.org/10.5194/acp-18-921-2018, https://doi.org/10.5194/acp-18-921-2018, 2018
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We made airborne measurements of aerosol particle concentrations and properties over the Amazon Basin. We found extremely high concentrations of very small particles in the region between 8 and 14 km altitude all across the basin, which had been recently formed by gas-to-particle conversion at these altitudes. This makes the upper troposphere a very important source region of atmospheric particles with significant implications for the Earth's climate system.
Joel Brito, Evelyn Freney, Pamela Dominutti, Agnes Borbon, Sophie L. Haslett, Anneke M. Batenburg, Aurelie Colomb, Regis Dupuy, Cyrielle Denjean, Frederic Burnet, Thierry Bourriane, Adrien Deroubaix, Karine Sellegri, Stephan Borrmann, Hugh Coe, Cyrille Flamant, Peter Knippertz, and Alfons Schwarzenboeck
Atmos. Chem. Phys., 18, 757–772, https://doi.org/10.5194/acp-18-757-2018, https://doi.org/10.5194/acp-18-757-2018, 2018
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This work focuses on sources of submicron aerosol particles over southern West Africa (SWA). Results have shown that isoprene, a gas-phase compound of biogenic origin, is responsible for roughly 25 % of the organic aerosol (OA) loading, under most background or urban plumes alike. This fraction represents a lower estimate from the biogenic contribution in this fairly polluted region. This work sheds light upon the role of anthropogenic and biogenic emissions on the pollution burden over SWA.
Adrien Deroubaix, Cyrille Flamant, Laurent Menut, Guillaume Siour, Sylvain Mailler, Solène Turquety, Régis Briant, Dmitry Khvorostyanov, and Suzanne Crumeyrolle
Atmos. Chem. Phys., 18, 445–465, https://doi.org/10.5194/acp-18-445-2018, https://doi.org/10.5194/acp-18-445-2018, 2018
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CO and PM2.5 are analyzed over the Guinean Gulf coastal region during the beginning of the 2006 West African monsoon. A biomass burning plume from Central Africa is observed since June at the Guinean coast. In June, the modeled anthropogenic PM2.5 concentrations are higher than in May or July. An important part of the pollution emitted along the coastline is transported to the north at night within the surface layer and within the nocturnal low-level jet.
Romy Heller, Christiane Voigt, Stuart Beaton, Andreas Dörnbrack, Andreas Giez, Stefan Kaufmann, Christian Mallaun, Hans Schlager, Johannes Wagner, Kate Young, and Markus Rapp
Atmos. Chem. Phys., 17, 14853–14869, https://doi.org/10.5194/acp-17-14853-2017, https://doi.org/10.5194/acp-17-14853-2017, 2017
Adrian Walser, Daniel Sauer, Antonio Spanu, Josef Gasteiger, and Bernadett Weinzierl
Atmos. Meas. Tech., 10, 4341–4361, https://doi.org/10.5194/amt-10-4341-2017, https://doi.org/10.5194/amt-10-4341-2017, 2017
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We present a new approach to model the response of optical particle counters (OPCs) including a simple parametrization for artificial broadening of size spectra induced by the non-ideal behavior of real OPCs. We show a self-consistent way to evaluate calibration measurements and outline how particle number size distributions with realistic uncertainty estimates can be derived. The innovations will improve the accuracy of OPC-derived size distributions and allow to assess their precision.
Daniel Rieger, Andrea Steiner, Vanessa Bachmann, Philipp Gasch, Jochen Förstner, Konrad Deetz, Bernhard Vogel, and Heike Vogel
Atmos. Chem. Phys., 17, 13391–13415, https://doi.org/10.5194/acp-17-13391-2017, https://doi.org/10.5194/acp-17-13391-2017, 2017
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The importance for reliable forecasts of incoming solar radiation is growing rapidly, especially for those countries with an increasing share in photovoltaic (PV) power production. We investigate the impact of mineral dust on the PV power generation during a Saharan dust outbreak over Germany on 4 April 2014. We find an overall improvement of the PV power forecast for 65 % of the pyranometer stations in Germany.
Stefanie Falk, Björn-Martin Sinnhuber, Gisèle Krysztofiak, Patrick Jöckel, Phoebe Graf, and Sinikka T. Lennartz
Atmos. Chem. Phys., 17, 11313–11329, https://doi.org/10.5194/acp-17-11313-2017, https://doi.org/10.5194/acp-17-11313-2017, 2017
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Brominated very short-lived source gases (VSLS) contribute significantly to the tropospheric and stratospheric bromine loading. We find an increase of future ocean–atmosphere flux of brominated VSLS of 8–10 % compared to present day. A decrease in the tropospheric mixing ratios of VSLS and an increase in the lower stratosphere are attributed to changes in atmospheric chemistry and transport. Bromine impact on stratospheric ozone at the end of the 21st century is reduced compared to present day.
Jean-Christophe Raut, Louis Marelle, Jerome D. Fast, Jennie L. Thomas, Bernadett Weinzierl, Katharine S. Law, Larry K. Berg, Anke Roiger, Richard C. Easter, Katharina Heimerl, Tatsuo Onishi, Julien Delanoë, and Hans Schlager
Atmos. Chem. Phys., 17, 10969–10995, https://doi.org/10.5194/acp-17-10969-2017, https://doi.org/10.5194/acp-17-10969-2017, 2017
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We study the cross-polar transport of plumes from Siberian fires to the Arctic in summer, both in terms of transport pathways and efficiency of deposition processes. Those plumes containing soot may originate from anthropogenic and biomass burning sources in mid-latitude regions and may impact the Arctic climate by depositing on snow and ice surfaces. We evaluate the role of the respective source contributions, investigate the transport of plumes and treat pathway-dependent removal of particles.
Peter Knippertz, Andreas H. Fink, Adrien Deroubaix, Eleanor Morris, Flore Tocquer, Mat J. Evans, Cyrille Flamant, Marco Gaetani, Christophe Lavaysse, Celine Mari, John H. Marsham, Rémi Meynadier, Abalo Affo-Dogo, Titike Bahaga, Fabien Brosse, Konrad Deetz, Ridha Guebsi, Issaou Latifou, Marlon Maranan, Philip D. Rosenberg, and Andreas Schlueter
Atmos. Chem. Phys., 17, 10893–10918, https://doi.org/10.5194/acp-17-10893-2017, https://doi.org/10.5194/acp-17-10893-2017, 2017
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In June–July 2016 DACCIWA (Dynamics–Aerosol–Chemistry–Cloud Interactions in West Africa), a large, EU-funded European–African project, organised an international field campaign in densely populated southern West Africa, including measurements from ground sites, research aircraft, weather balloons and urban sites. This paper gives an overview of the atmospheric evolution during this period focusing on meteorological (precipitation, cloudiness, winds) and composition (gases, particles) aspects.
Michael Weimer, Jennifer Schröter, Johannes Eckstein, Konrad Deetz, Marco Neumaier, Garlich Fischbeck, Lu Hu, Dylan B. Millet, Daniel Rieger, Heike Vogel, Bernhard Vogel, Thomas Reddmann, Oliver Kirner, Roland Ruhnke, and Peter Braesicke
Geosci. Model Dev., 10, 2471–2494, https://doi.org/10.5194/gmd-10-2471-2017, https://doi.org/10.5194/gmd-10-2471-2017, 2017
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In this paper, the recently developed module for trace gas emissions in the online coupled modelling framework ICON-ART for atmospheric chemistry is presented. Algorithms for offline and online calculation of the emissions are described. The module is validated with ground-based as well as airborne measurements of acetone. It is shown that the module performs well and allows the simulation of annual cycles of emission-driven trace gases.
Klaus-D. Gottschaldt, Hans Schlager, Robert Baumann, Heiko Bozem, Veronika Eyring, Peter Hoor, Patrick Jöckel, Tina Jurkat, Christiane Voigt, Andreas Zahn, and Helmut Ziereis
Atmos. Chem. Phys., 17, 6091–6111, https://doi.org/10.5194/acp-17-6091-2017, https://doi.org/10.5194/acp-17-6091-2017, 2017
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We present upper-tropospheric trace gas measurements in the Asian summer monsoon anticyclone, obtained with the HALO research aircraft in September 2012. The anticyclone is one of the largest atmospheric features on Earth, but many aspects of it are not well understood. With the help of model simulations we find that entrainments from the tropopause region and the lower troposphere, combined with photochemistry and dynamical instabilities, can explain the observations.
Konrad Deetz and Bernhard Vogel
Geosci. Model Dev., 10, 1607–1620, https://doi.org/10.5194/gmd-10-1607-2017, https://doi.org/10.5194/gmd-10-1607-2017, 2017
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A new gas flaring emission data set for CO, CO2, NO, NO2 and SO2 has been developed, which combines remote sensing observations with combustion equations. The physically based parameterization can easily be applied to different research domains, e.g., to provide flaring emission datasets for chemistry models. Within the project DACCIWA, we have derived a flaring data set for southern West Africa and compared the results to pre-existing emission inventories.
Christopher E. Sioris, Landon A. Rieger, Nicholas D. Lloyd, Adam E. Bourassa, Chris Z. Roth, Douglas A. Degenstein, Claude Camy-Peyret, Klaus Pfeilsticker, Gwenaël Berthet, Valéry Catoire, Florence Goutail, Jean-Pierre Pommereau, and Chris A. McLinden
Atmos. Meas. Tech., 10, 1155–1168, https://doi.org/10.5194/amt-10-1155-2017, https://doi.org/10.5194/amt-10-1155-2017, 2017
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A new OSIRIS NO2 retrieval algorithm is described and validated using > 40 balloon-based profile measurements. The validation results indicate a slight improvement relative to the existing operational algorithm in terms of the bias versus the balloon data, particularly in the lower stratosphere. The implication is that this new algorithm should replace the operational one. The motivation was to combine spectral fitting and the SaskTRAN radiative transfer model to achieve an improved product.
Régis Briant, Paolo Tuccella, Adrien Deroubaix, Dmitry Khvorostyanov, Laurent Menut, Sylvain Mailler, and Solène Turquety
Geosci. Model Dev., 10, 927–944, https://doi.org/10.5194/gmd-10-927-2017, https://doi.org/10.5194/gmd-10-927-2017, 2017
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This paper presents the coupling of the CHIMERE chemistry-transport model with the WRF meteorological model, using the OASIS3-MCT coupler. WRF meteorological fields along with CHIMERE aerosol optical properties are exchanged through the coupler at a high frequency in order to model the aerosol direct and semi-direct effects.
Norbert Glatthor, Michael Höpfner, Adrian Leyser, Gabriele P. Stiller, Thomas von Clarmann, Udo Grabowski, Sylvia Kellmann, Andrea Linden, Björn-Martin Sinnhuber, Gisèle Krysztofiak, and Kaley A. Walker
Atmos. Chem. Phys., 17, 2631–2652, https://doi.org/10.5194/acp-17-2631-2017, https://doi.org/10.5194/acp-17-2631-2017, 2017
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To date, information on the global distribution of atmospheric carbonyl sulfide (OCS) is still rather sparse.
However, detailed knowledge of the OCS distribution is of scientific interest, because this trace gas is on one of the major sources of atmospheric sulfur, which is a prerequisite of the stratospheric aerosol layer. Under this aspect we present a comprehensive space-borne data set of global OCS concentrations covering the period from June 2002 to April 2012.
Gwenaël Berthet, Fabrice Jégou, Valéry Catoire, Gisèle Krysztofiak, Jean-Baptiste Renard, Adam E. Bourassa, Doug A. Degenstein, Colette Brogniez, Marcel Dorf, Sebastian Kreycy, Klaus Pfeilsticker, Bodo Werner, Franck Lefèvre, Tjarda J. Roberts, Thibaut Lurton, Damien Vignelles, Nelson Bègue, Quentin Bourgeois, Daniel Daugeron, Michel Chartier, Claude Robert, Bertrand Gaubicher, and Christophe Guimbaud
Atmos. Chem. Phys., 17, 2229–2253, https://doi.org/10.5194/acp-17-2229-2017, https://doi.org/10.5194/acp-17-2229-2017, 2017
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Since the last major volcanic event, i.e. the Pinatubo eruption in 1991, only
moderateeruptions have regularly injected sulfur into the stratosphere, typically enhancing the aerosol loading for several months. We investigate here for the first time the chemical perturbation associated with the Sarychev eruption in June 2009, using balloon-borne instruments and model calculations. Some chemical compounds are significantly affected by the aerosols, but the impact on stratospheric ozone is weak.
Ulrich Schumann, Christoph Kiemle, Hans Schlager, Ralf Weigel, Stephan Borrmann, Francesco D'Amato, Martina Krämer, Renaud Matthey, Alain Protat, Christiane Voigt, and C. Michael Volk
Atmos. Chem. Phys., 17, 2311–2346, https://doi.org/10.5194/acp-17-2311-2017, https://doi.org/10.5194/acp-17-2311-2017, 2017
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A long-lived (1 h) contrail and overshooting convection were observed in the tropics, near Darwin, Australia. The data are used to study the contrail life cycle at low temperatures and cirrus from deep overturning convection in the lower tropical stratosphere. Airborne in situ, lidar, profiler, radar, and satellite data, as well as a photo, are used to distinguish contrail cirrus from convective cirrus and to study the origin of the observed ice and aerosol, up to 2.3 km above the tropopause.
Ulrich Schumann, Robert Baumann, Darrel Baumgardner, Sarah T. Bedka, David P. Duda, Volker Freudenthaler, Jean-Francois Gayet, Andrew J. Heymsfield, Patrick Minnis, Markus Quante, Ehrhard Raschke, Hans Schlager, Margarita Vázquez-Navarro, Christiane Voigt, and Zhien Wang
Atmos. Chem. Phys., 17, 403–438, https://doi.org/10.5194/acp-17-403-2017, https://doi.org/10.5194/acp-17-403-2017, 2017
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The initially linear clouds often seen behind aircraft are known as contrails. Contrails are prototype cirrus clouds forming under well-known conditions, but with less certain life cycle and climate effects. This paper collects contrail data from a large set of measurements and compares them among each other and with models. The observations show consistent contrail properties over a wide range of aircraft and atmosphere conditions. The dataset is available for further research.
Josef Gasteiger, Silke Groß, Daniel Sauer, Moritz Haarig, Albert Ansmann, and Bernadett Weinzierl
Atmos. Chem. Phys., 17, 297–311, https://doi.org/10.5194/acp-17-297-2017, https://doi.org/10.5194/acp-17-297-2017, 2017
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To study aerosol transport in the Saharan Air Layer (SAL) from Africa to the Caribbean, we combine advanced optical models of Saharan aerosols with Stokes settling and two hypotheses about the occurrence of vertical mixing. By testing our hypotheses with lidar and in situ profiles measured near the top of the transported SAL, we find strong evidence that vertical mixing occurs in the SAL over the Atlantic with significant consequences for size distribution of the transported Saharan aerosols.
Gerard Ancellet, Nikos Daskalakis, Jean Christophe Raut, David Tarasick, Jonathan Hair, Boris Quennehen, François Ravetta, Hans Schlager, Andrew J. Weinheimer, Anne M. Thompson, Bryan Johnson, Jennie L. Thomas, and Katharine S. Law
Atmos. Chem. Phys., 16, 13341–13358, https://doi.org/10.5194/acp-16-13341-2016, https://doi.org/10.5194/acp-16-13341-2016, 2016
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An integrated analysis of all the ozone observations (lidar, sondes, and airborne in situ measurements) conducted during the 2008 IPY campaigns is performed and the processes that determine summer ozone concentrations over Greenland and Canada are discussed. Combined with a regional model simulation (WRFChem), the analysis of ozone, CO, and PV latitudinal and vertical variability allows the determination of the influence of stratospheric sources and biomass burning and anthropogenic emissions.
Silke Groß, Josef Gasteiger, Volker Freudenthaler, Thomas Müller, Daniel Sauer, Carlos Toledano, and Albert Ansmann
Atmos. Chem. Phys., 16, 11535–11546, https://doi.org/10.5194/acp-16-11535-2016, https://doi.org/10.5194/acp-16-11535-2016, 2016
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Dual-wavelength depolarization sensitive Raman lidar measurements were used to characterize the optical properties of the dust loaded convective boundary layer over the Caribbean. Furthermore we derived the dust volume fraction and dust mass concentration within the convective boundary layer.
Stefan Müller, Peter Hoor, Heiko Bozem, Ellen Gute, Bärbel Vogel, Andreas Zahn, Harald Bönisch, Timo Keber, Martina Krämer, Christian Rolf, Martin Riese, Hans Schlager, and Andreas Engel
Atmos. Chem. Phys., 16, 10573–10589, https://doi.org/10.5194/acp-16-10573-2016, https://doi.org/10.5194/acp-16-10573-2016, 2016
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In situ airborne measurements performed during TACTS/ESMVal 2012 were analysed to investigate the chemical compostion of the upper troposphere and lower stratosphere. N2O, CO and O3 data show an increase in tropospherically affected air masses within the extratropical stratosphere from August to September 2012, which originate from the Asian monsoon region. Thus, the Asian monsoon anticyclone significantly affected the chemical composition of the extratropical stratosphere during summer 2012.
R. Hossaini, P. K. Patra, A. A. Leeson, G. Krysztofiak, N. L. Abraham, S. J. Andrews, A. T. Archibald, J. Aschmann, E. L. Atlas, D. A. Belikov, H. Bönisch, L. J. Carpenter, S. Dhomse, M. Dorf, A. Engel, W. Feng, S. Fuhlbrügge, P. T. Griffiths, N. R. P. Harris, R. Hommel, T. Keber, K. Krüger, S. T. Lennartz, S. Maksyutov, H. Mantle, G. P. Mills, B. Miller, S. A. Montzka, F. Moore, M. A. Navarro, D. E. Oram, K. Pfeilsticker, J. A. Pyle, B. Quack, A. D. Robinson, E. Saikawa, A. Saiz-Lopez, S. Sala, B.-M. Sinnhuber, S. Taguchi, S. Tegtmeier, R. T. Lidster, C. Wilson, and F. Ziska
Atmos. Chem. Phys., 16, 9163–9187, https://doi.org/10.5194/acp-16-9163-2016, https://doi.org/10.5194/acp-16-9163-2016, 2016
Armin Rauthe-Schöch, Angela K. Baker, Tanja J. Schuck, Carl A. M. Brenninkmeijer, Andreas Zahn, Markus Hermann, Greta Stratmann, Helmut Ziereis, Peter F. J. van Velthoven, and Jos Lelieveld
Atmos. Chem. Phys., 16, 3609–3629, https://doi.org/10.5194/acp-16-3609-2016, https://doi.org/10.5194/acp-16-3609-2016, 2016
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The flying laboratory CARIBIC onboard a passenger aircraft measured trace gases and aerosol particles in the upper tropospheric Indian summer monsoon anticyclone in summer 2008. We used the measurements together with meteorological analyses to investigate the chemical signature of the northern and southern part of the monsoon, the source regions from where the air was entrained into the monsoon and which parts of the world received polluted air that had been chemically processed in the monsoon.
Louis Marelle, Jennie L. Thomas, Jean-Christophe Raut, Kathy S. Law, Jukka-Pekka Jalkanen, Lasse Johansson, Anke Roiger, Hans Schlager, Jin Kim, Anja Reiter, and Bernadett Weinzierl
Atmos. Chem. Phys., 16, 2359–2379, https://doi.org/10.5194/acp-16-2359-2016, https://doi.org/10.5194/acp-16-2359-2016, 2016
S. T. Lennartz, G. Krysztofiak, C. A. Marandino, B.-M. Sinnhuber, S. Tegtmeier, F. Ziska, R. Hossaini, K. Krüger, S. A. Montzka, E. Atlas, D. E. Oram, T. Keber, H. Bönisch, and B. Quack
Atmos. Chem. Phys., 15, 11753–11772, https://doi.org/10.5194/acp-15-11753-2015, https://doi.org/10.5194/acp-15-11753-2015, 2015
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Marine-produced short-lived trace gases such as halocarbons and DMS significantly impact atmospheric chemistry. To assess this impact on ozone depletion and the radiative budget, it is critical that their marine emissions in atmospheric chemistry models are quantified as accurately as possible. We show that calculating emissions online with an interactive atmosphere improves the agreement with current observations and should be employed regularly in models where marine sources are important.
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.
C. Rolf, A. Afchine, H. Bozem, B. Buchholz, V. Ebert, T. Guggenmoser, P. Hoor, P. Konopka, E. Kretschmer, S. Müller, H. Schlager, N. Spelten, O. Sumińska-Ebersoldt, J. Ungermann, A. Zahn, and M. Krämer
Atmos. Chem. Phys., 15, 9143–9158, https://doi.org/10.5194/acp-15-9143-2015, https://doi.org/10.5194/acp-15-9143-2015, 2015
M. Höpfner, C. D. Boone, B. Funke, N. Glatthor, U. Grabowski, A. Günther, S. Kellmann, M. Kiefer, A. Linden, S. Lossow, H. C. Pumphrey, W. G. Read, A. Roiger, G. Stiller, H. Schlager, T. von Clarmann, and K. Wissmüller
Atmos. Chem. Phys., 15, 7017–7037, https://doi.org/10.5194/acp-15-7017-2015, https://doi.org/10.5194/acp-15-7017-2015, 2015
S. A. Monks, S. R. Arnold, L. K. Emmons, K. S. Law, S. Turquety, B. N. Duncan, J. Flemming, V. Huijnen, S. Tilmes, J. Langner, J. Mao, Y. Long, J. L. Thomas, S. D. Steenrod, J. C. Raut, C. Wilson, M. P. Chipperfield, G. S. Diskin, A. Weinheimer, H. Schlager, and G. Ancellet
Atmos. Chem. Phys., 15, 3575–3603, https://doi.org/10.5194/acp-15-3575-2015, https://doi.org/10.5194/acp-15-3575-2015, 2015
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Multi-model simulations of Arctic CO, O3 and OH are evaluated using observations. Models show highly variable concentrations but the relative importance of emission regions and types is robust across the models, demonstrating the importance of biomass burning as a source. Idealised tracer experiments suggest that some of the model spread is due to variations in simulated transport from Europe in winter and from Asia throughout the year.
M. Kaufmann, J. Blank, T. Guggenmoser, J. Ungermann, A. Engel, M. Ern, F. Friedl-Vallon, D. Gerber, J. U. Grooß, G. Guenther, M. Höpfner, A. Kleinert, E. Kretschmer, Th. Latzko, G. Maucher, T. Neubert, H. Nordmeyer, H. Oelhaf, F. Olschewski, J. Orphal, P. Preusse, H. Schlager, H. Schneider, D. Schuettemeyer, F. Stroh, O. Suminska-Ebersoldt, B. Vogel, C. M. Volk, W. Woiwode, and M. Riese
Atmos. Meas. Tech., 8, 81–95, https://doi.org/10.5194/amt-8-81-2015, https://doi.org/10.5194/amt-8-81-2015, 2015
Y. Ren, R. Baumann, and H. Schlager
Atmos. Meas. Tech., 8, 69–80, https://doi.org/10.5194/amt-8-69-2015, https://doi.org/10.5194/amt-8-69-2015, 2015
R. Pommrich, R. Müller, J.-U. Grooß, P. Konopka, F. Ploeger, B. Vogel, M. Tao, C. M. Hoppe, G. Günther, N. Spelten, L. Hoffmann, H.-C. Pumphrey, S. Viciani, F. D'Amato, C. M. Volk, P. Hoor, H. Schlager, and M. Riese
Geosci. Model Dev., 7, 2895–2916, https://doi.org/10.5194/gmd-7-2895-2014, https://doi.org/10.5194/gmd-7-2895-2014, 2014
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A version of the chemical transport model CLaMS is presented, which features a simplified (numerically inexpensive) chemistry scheme. The model results using this version of CLaMS show a good representation of anomaly fields of CO, CH4, N2O, and CFC-11 in the lower stratosphere. CO measurements of three instruments (COLD, HAGAR, and Falcon-CO) in the lower tropical stratosphere (during the campaign TROCCINOX in 2005) have been compared and show a good agreement within the error bars.
S. Molleker, S. Borrmann, H. Schlager, B. Luo, W. Frey, M. Klingebiel, R. Weigel, M. Ebert, V. Mitev, R. Matthey, W. Woiwode, H. Oelhaf, A. Dörnbrack, G. Stratmann, J.-U. Grooß, G. Günther, B. Vogel, R. Müller, M. Krämer, J. Meyer, and F. Cairo
Atmos. Chem. Phys., 14, 10785–10801, https://doi.org/10.5194/acp-14-10785-2014, https://doi.org/10.5194/acp-14-10785-2014, 2014
G. Ganbavale, C. Marcolli, U. K. Krieger, A. Zuend, G. Stratmann, and T. Peter
Atmos. Chem. Phys., 14, 9993–10012, https://doi.org/10.5194/acp-14-9993-2014, https://doi.org/10.5194/acp-14-9993-2014, 2014
J. Tian, N. Riemer, M. West, L. Pfaffenberger, H. Schlager, and A. Petzold
Atmos. Chem. Phys., 14, 5327–5347, https://doi.org/10.5194/acp-14-5327-2014, https://doi.org/10.5194/acp-14-5327-2014, 2014
J.-U. Grooß, I. Engel, S. Borrmann, W. Frey, G. Günther, C. R. Hoyle, R. Kivi, B. P. Luo, S. Molleker, T. Peter, M. C. Pitts, H. Schlager, G. Stiller, H. Vömel, K. A. Walker, and R. Müller
Atmos. Chem. Phys., 14, 1055–1073, https://doi.org/10.5194/acp-14-1055-2014, https://doi.org/10.5194/acp-14-1055-2014, 2014
P. Jeßberger, C. Voigt, U. Schumann, I. Sölch, H. Schlager, S. Kaufmann, A. Petzold, D. Schäuble, and J.-F. Gayet
Atmos. Chem. Phys., 13, 11965–11984, https://doi.org/10.5194/acp-13-11965-2013, https://doi.org/10.5194/acp-13-11965-2013, 2013
M. von Hobe, S. Bekki, S. Borrmann, F. Cairo, F. D'Amato, G. Di Donfrancesco, A. Dörnbrack, A. Ebersoldt, M. Ebert, C. Emde, I. Engel, M. Ern, W. Frey, S. Genco, S. Griessbach, J.-U. Grooß, T. Gulde, G. Günther, E. Hösen, L. Hoffmann, V. Homonnai, C. R. Hoyle, I. S. A. Isaksen, D. R. Jackson, I. M. Jánosi, R. L. Jones, K. Kandler, C. Kalicinsky, A. Keil, S. M. Khaykin, F. Khosrawi, R. Kivi, J. Kuttippurath, J. C. Laube, F. Lefèvre, R. Lehmann, S. Ludmann, B. P. Luo, M. Marchand, J. Meyer, V. Mitev, S. Molleker, R. Müller, H. Oelhaf, F. Olschewski, Y. Orsolini, T. Peter, K. Pfeilsticker, C. Piesch, M. C. Pitts, L. R. Poole, F. D. Pope, F. Ravegnani, M. Rex, M. Riese, T. Röckmann, B. Rognerud, A. Roiger, C. Rolf, M. L. Santee, M. Scheibe, C. Schiller, H. Schlager, M. Siciliani de Cumis, N. Sitnikov, O. A. Søvde, R. Spang, N. Spelten, F. Stordal, O. Sumińska-Ebersoldt, A. Ulanovski, J. Ungermann, S. Viciani, C. M. Volk, M. vom Scheidt, P. von der Gathen, K. Walker, T. Wegner, R. Weigel, S. Weinbruch, G. Wetzel, F. G. Wienhold, I. Wohltmann, W. Woiwode, I. A. K. Young, V. Yushkov, B. Zobrist, and F. Stroh
Atmos. Chem. Phys., 13, 9233–9268, https://doi.org/10.5194/acp-13-9233-2013, https://doi.org/10.5194/acp-13-9233-2013, 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, Emma C. Leedham Elvidge, 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
J. L. Thomas, J.-C. Raut, K. S. Law, L. Marelle, G. Ancellet, F. Ravetta, J. D. Fast, G. Pfister, L. K. Emmons, G. S. Diskin, A. Weinheimer, A. Roiger, and H. Schlager
Atmos. Chem. Phys., 13, 3825–3848, https://doi.org/10.5194/acp-13-3825-2013, https://doi.org/10.5194/acp-13-3825-2013, 2013
K. A. Cummings, T. L. Huntemann, K. E. Pickering, M. C. Barth, W. C. Skamarock, H. Höller, H.-D. Betz, A. Volz-Thomas, and H. Schlager
Atmos. Chem. Phys., 13, 2757–2777, https://doi.org/10.5194/acp-13-2757-2013, https://doi.org/10.5194/acp-13-2757-2013, 2013
Related subject area
Subject: Gases | Research Activity: Field Measurements | Altitude Range: Troposphere | Science Focus: Chemistry (chemical composition and reactions)
Measurement report: Exploring the variations in ambient BTEX in urban Europe and their environmental health implications
Seasonal air concentration variability, gas–particle partitioning, precipitation scavenging, and air–water equilibrium of organophosphate esters in southern Canada
Measurement report: Surface exchange fluxes of HONO during the growth process of paddy fields in the Huaihe River Basin, China
Molecular and seasonal characteristics of organic vapors in urban Beijing: insights from Vocus-PTR measurements
The variations in volatile organic compounds based on the policy change for Omicron in the traffic hub of Zhengzhou
On the dynamics of ozone depletion events at Villum Research Station in the High Arctic
Measurement report: Long-term measurements of surface ozone and trends in semi-natural sub-Saharan African ecosystems
Characterization of biogenic volatile organic compounds and their oxidation products in a stressed spruce-dominated forest close to a biogas power plant
Reactive chlorine-, sulfur-, and nitrogen-containing volatile organic compounds impact atmospheric chemistry in the megacity of Delhi during both clean and extremely polluted seasons
Analysis of the day-to-day variability of ozone vertical profiles in the lower troposphere during the 2022 Paris ACROSS campaign
Ozone deposition measurements over wheat fields in the North China Plain: variability and related factors of deposition flux and velocity
Consistency evaluation of tropospheric ozone from ozonesonde and IAGOS (In-service Aircraft for a Global Observing System) observations: vertical distribution, ozonesonde types, and station–airport distance
CO2 and CO temporal variability over Mexico City from ground-based total column and surface measurements
Investigating carbonyl compounds above the Amazon rainforest using a proton-transfer-reaction time-of-flight mass spectrometer (PTR-ToF-MS) with NO+ chemical ionization
Measurement report: In-flight and ground-based measurements of nitrogen oxide emissions from latest-generation jet engines and 100 % sustainable aviation fuel
Vertical changes in volatile organic compounds (VOCs) and impacts on photochemical ozone formation
Measurement report: Sources, sinks, and lifetime of NOx in a suburban temperate forest at night
Measurement report: Urban ammonia and amines in Houston, Texas
Biomass-burning sources control ambient particulate matter, but traffic and industrial sources control volatile organic compound (VOC) emissions and secondary-pollutant formation during extreme pollution events in Delhi
Multi-year observations of variable incomplete combustion in the New York megacity
Observations of the vertical distributions of summertime atmospheric pollutants in Nam Co: OH production and source analysis
Understanding summertime peroxyacetyl nitrate (PAN) formation and its relation to aerosol pollution: Insights from high-resolution measurements and modeling
Measurement report: Elevated atmospheric ammonia may promote particle pH and HONO formation – insights from the COVID-19 pandemic
Measurement report: Vertical and temporal variability in the near-surface ozone production rate and sensitivity in an urban area in the Pearl River Delta region, China
Elevated oxidized mercury in the free troposphere: analytical advances and application at a remote continental mountaintop site
Using observed urban NOx sinks to constrain VOC reactivity and the ozone and radical budget in the Seoul Metropolitan Area
Real-world emission characteristics of VOCs from typical cargo ships and their potential contributions to secondary organic aerosol and O3 under low-sulfur fuel policies
NO3 reactivity during a summer period in a temperate forest below and above the canopy
The role of oceanic ventilation and terrestrial outflow in atmospheric non-methane hydrocarbons over the Chinese marginal seas
Concentration and source changes of nitrous acid (HONO) during the COVID-19 lockdown in Beijing
Characteristics and sources of nonmethane volatile organic compounds (NMVOCs) and O3–NOx–NMVOC relationships in Zhengzhou, China
Cloud processing of DMS oxidation products limits SO2 and OCS production in the Eastern North Atlantic marine boundary layer
Deciphering anthropogenic and biogenic contributions to selected non-methane volatile organic compound emissions in an urban area
Emission characteristics of reactive organic gases (ROGs) from industrial volatile chemical products (VCPs) in the Pearl River Delta (PRD), China
Measurement report: Enhanced photochemical formation of formic and isocyanic acids in urban regions aloft – insights from tower-based online gradient measurements
Sources of organic gases and aerosol particles and their roles in nighttime particle growth at a rural forested site in southwest Germany
Exploring the Crucial Role of Atmospheric Carbonyl Compounds in Regional Ozone heavy Pollution: Insights from Intensive Field Observations and Observation-based modelling in the Chengdu Plain Urban Agglomeration, China
Surface snow bromide and nitrate at Eureka, Canada, in early spring and implications for polar boundary layer chemistry
Opinion: Strengthening research in the Global South – atmospheric science opportunities in South America and Africa
Shipping and algae emissions have a major impact on ambient air mixing ratios of non-methane hydrocarbons (NMHCs) and methanethiol on Utö Island in the Baltic Sea
Contribution of cooking emissions to the urban volatile organic compounds in Las Vegas, NV
Reanalysis of NOAA H2 observations: implications for the H2 budget
A large role of missing volatile organic compound reactivity from anthropogenic emissions in ozone pollution regulation
Diurnal, seasonal, and interannual variations in δ(18O) of atmospheric O2 and its application to evaluate changes in oxygen, carbon, and water cycles
Measurement report: Insights into the chemical composition and origin of molecular clusters and potential precursor molecules present in the free troposphere over the southern Indian Ocean: observations from the Maïdo Observatory (2150 m a.s.l., Réunion)
Production of oxygenated volatile organic compounds from the ozonolysis of coastal seawater
Comment on “Transport of substantial stratospheric ozone to the surface by a dying typhoon and shallow convection” by Chen et al. (2022)
Characterization of nitrous acid and its potential effects on secondary pollution in warm-season of Beijing urban areas
Observations of cyanogen bromide (BrCN) in the global troposphere and their relation to polar surface O3 destruction
Individual coal mine methane emissions constrained by eddy covariance measurements: low bias and missing sources
Xiansheng Liu, Xun Zhang, Marvin Dufresne, Tao Wang, Lijie Wu, Rosa Lara, Roger Seco, Marta Monge, Ana Maria Yáñez-Serrano, Marie Gohy, Paul Petit, Audrey Chevalier, Marie-Pierre Vagnot, Yann Fortier, Alexia Baudic, Véronique Ghersi, Grégory Gille, Ludovic Lanzi, Valérie Gros, Leïla Simon, Heidi Héllen, Stefan Reimann, Zoé Le Bras, Michelle Jessy Müller, David Beddows, Siqi Hou, Zongbo Shi, Roy M. Harrison, William Bloss, James Dernie, Stéphane Sauvage, Philip K. Hopke, Xiaoli Duan, Taicheng An, Alastair C. Lewis, James R. Hopkins, Eleni Liakakou, Nikolaos Mihalopoulos, Xiaohu Zhang, Andrés Alastuey, Xavier Querol, and Thérèse Salameh
Atmos. Chem. Phys., 25, 625–638, https://doi.org/10.5194/acp-25-625-2025, https://doi.org/10.5194/acp-25-625-2025, 2025
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This study examines BTEX (benzene, toluene, ethylbenzene, xylenes) pollution in urban areas across seven European countries. Analyzing data from 22 monitoring sites, we found traffic and industrial activities significantly impact BTEX levels, with peaks during rush hours. The risk from BTEX exposure remains moderate, especially in high-traffic and industrial zones, highlighting the need for targeted air quality management to protect public health and improve urban air quality.
Yuening Li, Faqiang Zhan, Chubashini Shunthirasingham, Ying Duan Lei, Jenny Oh, Amina Ben Chaaben, Zhe Lu, Kelsey Lee, Frank A. P. C. Gobas, Hayley Hung, and Frank Wania
Atmos. Chem. Phys., 25, 459–472, https://doi.org/10.5194/acp-25-459-2025, https://doi.org/10.5194/acp-25-459-2025, 2025
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Organophosphate esters are important humanmade trace contaminants. Measuring them in the atmospheric gas phase, particles, precipitation, and surface water in Canada, we explore seasonal concentration variability, gas–particle partitioning, precipitation scavenging, and the air–water equilibrium. Whereas higher summer concentrations and efficient precipitation scavenging conform with expectations, the lack of a relationship between compound volatility and gas–particle partitioning is puzzling.
Fanhao Meng, Baobin Han, Min Qin, Wu Fang, Ke Tang, Dou Shao, Zhitang Liao, Jun Duan, Yan Feng, Yong Huang, Ting Ni, and Pinhua Xie
Atmos. Chem. Phys., 24, 14191–14208, https://doi.org/10.5194/acp-24-14191-2024, https://doi.org/10.5194/acp-24-14191-2024, 2024
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Comprehensive observations of HONO and NOx fluxes were conducted over paddy fields in the Huaihe River Basin. Consecutive peaks in HONO and NO fluxes suggest a potentially enhanced release of HONO and NO due to soil tillage, whereas waterlogged soil may inhibit microbial nitrification processes following irrigation. Notably, biological processes and light-driven NO2 reactions at the surface may serve as sources of HONO and influence the local HONO budget during rotary tillage.
Zhaojin An, Rujing Yin, Xinyan Zhao, Xiaoxiao Li, Yuyang Li, Yi Yuan, Junchen Guo, Yiqi Zhao, Xue Li, Dandan Li, Yaowei Li, Dongbin Wang, Chao Yan, Kebin He, Douglas R. Worsnop, Frank N. Keutsch, and Jingkun Jiang
Atmos. Chem. Phys., 24, 13793–13810, https://doi.org/10.5194/acp-24-13793-2024, https://doi.org/10.5194/acp-24-13793-2024, 2024
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Online Vocus-PTR measurements show the compositions and seasonal variations in organic vapors in urban Beijing. With enhanced sensitivity and mass resolution, various species at a level of sub-parts per trillion (ppt) and organics with multiple oxygens (≥ 3) were observed. The fast photooxidation process in summer leads to an increase in both concentration and proportion of organics with multiple oxygens, while, in other seasons, the variations in them could be influenced by mixed sources.
Bowen Zhang, Dong Zhang, Zhe Dong, Xinshuai Song, Ruiqin Zhang, and Xiao Li
Atmos. Chem. Phys., 24, 13587–13601, https://doi.org/10.5194/acp-24-13587-2024, https://doi.org/10.5194/acp-24-13587-2024, 2024
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To gain insight into the impact of changes due to epidemic control policies, we undertook continuous online monitoring of volatile organic compounds (VOCs) at an urban site in Zhengzhou over a 2-month period. This study examines the characteristics of VOCs, their sources, and their temporal evolution. It also assesses the impact of the policy change on VOC pollution during the monitoring period, thus providing a basis for further research on VOC pollution and source control.
Jakob Boyd Pernov, Jens Liengaard Hjorth, Lise Lotte Sørensen, and Henrik Skov
Atmos. Chem. Phys., 24, 13603–13631, https://doi.org/10.5194/acp-24-13603-2024, https://doi.org/10.5194/acp-24-13603-2024, 2024
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Arctic ozone depletion events (ODEs) occur every spring and have vast implications for the oxidizing capacity, radiative balance, and mercury oxidation. In this study, we analyze ozone, ODEs, and their connection to meteorological and air mass history variables through statistical analyses, back trajectories, and machine learning (ML) at Villum Research Station. ODEs are favorable under sunny, calm conditions with air masses arriving from northerly wind directions with sea ice contact.
Hagninou Elagnon Venance Donnou, Aristide Barthélémy Akpo, Money Ossohou, Claire Delon, Véronique Yoboué, Dungall Laouali, Marie Ouafo-Leumbe, Pieter Gideon Van Zyl, Ousmane Ndiaye, Eric Gardrat, Maria Dias-Alves, and Corinne Galy-Lacaux
Atmos. Chem. Phys., 24, 13151–13182, https://doi.org/10.5194/acp-24-13151-2024, https://doi.org/10.5194/acp-24-13151-2024, 2024
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Ozone is a secondary air pollutant that is detrimental to human and plant health. A better understanding of its chemical evolution is a challenge for Africa, where it is still undersampled. Out of 14 sites examined (1995–2020), high levels of O3 are reported in southern Africa. The dominant chemical processes leading to O3 formation are identified. A decrease in O3 is observed at Katibougou (Mali) and Banizoumbou (Niger), and an increase is found at Zoétélé (Cameroon) and Skukuza (South Africa).
Junwei Song, Georgios I. Gkatzelis, Ralf Tillmann, Nicolas Brüggemann, Thomas Leisner, and Harald Saathoff
Atmos. Chem. Phys., 24, 13199–13217, https://doi.org/10.5194/acp-24-13199-2024, https://doi.org/10.5194/acp-24-13199-2024, 2024
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Biogenic volatile organic compounds (BVOCs) and organic aerosol (OA) particles were measured online in a stressed spruce-dominated forest. OA was mainly attributed to the monoterpene oxidation products. The mixing ratios of BVOCs were higher than the values previously measured in other temperate forests. The results demonstrate that BVOCs are influenced not only by meteorology and biogenic emissions but also by local anthropogenic emissions and subsequent chemical transformation processes.
Sachin Mishra, Vinayak Sinha, Haseeb Hakkim, Arpit Awasthi, Sachin D. Ghude, Vijay Kumar Soni, Narendra Nigam, Baerbel Sinha, and Madhavan N. Rajeevan
Atmos. Chem. Phys., 24, 13129–13150, https://doi.org/10.5194/acp-24-13129-2024, https://doi.org/10.5194/acp-24-13129-2024, 2024
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We quantified 111 gases using mass spectrometry to understand how seasonal and emission changes lead from clean air in the monsoon season to extremely polluted air in the post-monsoon season in Delhi. Averaged total mass concentrations (260 µg m-3) were > 4 times in polluted periods, driven by biomass burning emissions and reduced atmospheric ventilation. Reactive gaseous nitrogen, chlorine, and sulfur compounds hitherto unreported from such a polluted environment were discovered.
Gérard Ancellet, Camille Viatte, Anne Boynard, François Ravetta, Jacques Pelon, Cristelle Cailteau-Fischbach, Pascal Genau, Julie Capo, Axel Roy, and Philippe Nédélec
Atmos. Chem. Phys., 24, 12963–12983, https://doi.org/10.5194/acp-24-12963-2024, https://doi.org/10.5194/acp-24-12963-2024, 2024
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Characterization of ozone pollution in urban areas benefited from a measurement campaign in summer 2022 in the Paris region. The analysis is based on 21 d of lidar and aircraft observations. The main objective is an analysis of the sensitivity of ozone pollution to the micrometeorological processes in the urban atmospheric boundary layer and the transport of regional pollution. The paper also discusses to what extent satellite observations can track observed ozone plumes.
Xiaoyi Zhang, Wanyun Xu, Weili Lin, Gen Zhang, Jinjian Geng, Li Zhou, Huarong Zhao, Sanxue Ren, Guangsheng Zhou, Jianmin Chen, and Xiaobin Xu
Atmos. Chem. Phys., 24, 12323–12340, https://doi.org/10.5194/acp-24-12323-2024, https://doi.org/10.5194/acp-24-12323-2024, 2024
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Ozone (O3) deposition is a key process that removes surface O3, affecting air quality, ecosystems and climate change. We conducted O3 deposition measurement over a wheat canopy using a newly relaxed eddy accumulation flux system. Large variabilities in O3 deposition were detected, mainly determined by crop growth and modulated by various environmental factors. More O3 deposition observations over different surfaces are needed for exploring deposition mechanisms and model optimization.
Honglei Wang, David W. Tarasick, Jane Liu, Herman G. J. Smit, Roeland Van Malderen, Lijuan Shen, Romain Blot, and Tianliang Zhao
Atmos. Chem. Phys., 24, 11927–11942, https://doi.org/10.5194/acp-24-11927-2024, https://doi.org/10.5194/acp-24-11927-2024, 2024
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In this study, we identify 23 suitable pairs of sites from World Ozone and Ultraviolet Radiation Data Centre (WOUDC) and In-service Aircraft for a Global Observing System (IAGOS) datasets (1995 to 2021), compare the average vertical distributions of tropospheric O3 from ozonesonde and aircraft measurements, and analyze the differences based on ozonesonde type and station–airport distance.
Noémie Taquet, Wolfgang Stremme, María Eugenia González del Castillo, Victor Almanza, Alejandro Bezanilla, Olivier Laurent, Carlos Alberti, Frank Hase, Michel Ramonet, Thomas Lauvaux, Ke Che, and Michel Grutter
Atmos. Chem. Phys., 24, 11823–11848, https://doi.org/10.5194/acp-24-11823-2024, https://doi.org/10.5194/acp-24-11823-2024, 2024
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We characterize the variability in CO and CO2 emissions over Mexico City from long-term time-resolved Fourier transform infrared spectroscopy solar absorption and surface measurements from 2013 to 2021. Using the average intraday CO growth rate from total columns, the average CO / CO2 ratio and TROPOMI data, we estimate the interannual variability in the CO and CO2 anthropogenic emissions of Mexico City, highlighting the effect of an unprecedented drop in activity due to the COVID-19 lockdown.
Akima Ringsdorf, Achim Edtbauer, Bruna Holanda, Christopher Poehlker, Marta O. Sá, Alessandro Araújo, Jürgen Kesselmeier, Jos Lelieveld, and Jonathan Williams
Atmos. Chem. Phys., 24, 11883–11910, https://doi.org/10.5194/acp-24-11883-2024, https://doi.org/10.5194/acp-24-11883-2024, 2024
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We show the average height distribution of separately observed aldehydes and ketones over a day and discuss their rainforest-specific sources and sinks as well as their seasonal changes above the Amazon. Ketones have much longer atmospheric lifetimes than aldehydes and thus different implications for atmospheric chemistry. However, they are commonly observed together, which we overcome by measuring with a NO+ chemical ionization mass spectrometer for the first time in the Amazon rainforest.
Theresa Harlass, Rebecca Dischl, Stefan Kaufmann, Raphael Märkl, Daniel Sauer, Monika Scheibe, Paul Stock, Tiziana Bräuer, Andreas Dörnbrack, Anke Roiger, Hans Schlager, Ulrich Schumann, Magdalena Pühl, Tobias Schripp, Tobias Grein, Linda Bondorf, Charles Renard, Maxime Gauthier, Mark Johnson, Darren Luff, Paul Madden, Peter Swann, Denise Ahrens, Reetu Sallinen, and Christiane Voigt
Atmos. Chem. Phys., 24, 11807–11822, https://doi.org/10.5194/acp-24-11807-2024, https://doi.org/10.5194/acp-24-11807-2024, 2024
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Emissions from aircraft have a direct impact on our climate. Here, we present airborne and ground-based measurement data of nitrogen oxides that were collected in the exhaust of an Airbus aircraft. We study the impact of burning fossil and sustainable aviation fuel on nitrogen oxide emissions at different engine settings related to combustor temperature, pressure and fuel flow. Further, we compare observations with engine emission models.
Xiao-Bing Li, Bin Yuan, Yibo Huangfu, Suxia Yang, Xin Song, Jipeng Qi, Xianjun He, Sihang Wang, Yubin Chen, Qing Yang, Yongxin Song, Yuwen Peng, Guiqian Tang, Jian Gao, and Min Shao
EGUsphere, https://doi.org/10.5194/egusphere-2024-2755, https://doi.org/10.5194/egusphere-2024-2755, 2024
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Online vertical gradient measurements of volatile organic compounds (VOCs), ozone, and NOx were made based on a 325 m tower in urban Beijing. Vertical changes in concentrations, compositions, key drivers, and environmental impacts of VOCs were analyzed in this study. We find that VOC species display differentiated vertical variation patterns and distinct roles in contributing to photochemical ozone formation with increasing height in the urban planetary boundary layer.
Simone T. Andersen, Max R. McGillen, Chaoyang Xue, Tobias Seubert, Patrick Dewald, Gunther N. T. E. Türk, Jan Schuladen, Cyrielle Denjean, Jean-Claude Etienne, Olivier Garrouste, Marina Jamar, Sergio Harb, Manuela Cirtog, Vincent Michoud, Mathieu Cazaunau, Antonin Bergé, Christopher Cantrell, Sebastien Dusanter, Bénédicte Picquet-Varrault, Alexandre Kukui, Abdelwahid Mellouki, Lucy J. Carpenter, Jos Lelieveld, and John N. Crowley
Atmos. Chem. Phys., 24, 11603–11618, https://doi.org/10.5194/acp-24-11603-2024, https://doi.org/10.5194/acp-24-11603-2024, 2024
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Using measurements of various trace gases in a suburban forest near Paris in the summer of 2022, we were able to gain insight into the sources and sinks of NOx (NO+NO2) with a special focus on their nighttime chemical and physical loss processes. NO was observed as a result of nighttime soil emissions when O3 levels were strongly depleted by deposition. NO oxidation products were not observed at night, indicating that soil and/or foliar surfaces are an efficient sink of reactive N.
Lee Tiszenkel, James H. Flynn, and Shan-Hu Lee
Atmos. Chem. Phys., 24, 11351–11363, https://doi.org/10.5194/acp-24-11351-2024, https://doi.org/10.5194/acp-24-11351-2024, 2024
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Ammonia and amines are important ingredients for aerosol formation in urban environments, but the measurements of these compounds are extremely challenging. Our observations show that urban ammonia and amines in Houston are emitted from urban sources, and diurnal variations in their concentrations are likely governed by gas-to-particle conversion and emissions.
Arpit Awasthi, Baerbel Sinha, Haseeb Hakkim, Sachin Mishra, Varkrishna Mummidivarapu, Gurmanjot Singh, Sachin D. Ghude, Vijay Kumar Soni, Narendra Nigam, Vinayak Sinha, and Madhavan N. Rajeevan
Atmos. Chem. Phys., 24, 10279–10304, https://doi.org/10.5194/acp-24-10279-2024, https://doi.org/10.5194/acp-24-10279-2024, 2024
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We use 111 volatile organic compounds (VOCs), PM10, and PM2.5 in a positive matrix factorization (PMF) model to resolve 11 pollution sources validated with chemical fingerprints. Crop residue burning and heating account for ~ 50 % of the PM, while traffic and industrial emissions dominate the gas-phase VOC burden and formation potential of secondary organic aerosols (> 60 %). Non-tailpipe emissions from compressed-natural-gas-fuelled commercial vehicles dominate the transport sector's PM burden.
Luke D. Schiferl, Cong Cao, Bronte Dalton, Andrew Hallward-Driemeier, Ricardo Toledo-Crow, and Róisín Commane
Atmos. Chem. Phys., 24, 10129–10142, https://doi.org/10.5194/acp-24-10129-2024, https://doi.org/10.5194/acp-24-10129-2024, 2024
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Carbon monoxide (CO) is an air pollutant and an important indicator of the incomplete combustion of fossil fuels in cities. Using 4 years of winter and spring observations in New York City, we found that both the magnitude and variability of CO from the metropolitan area are greater than expected. Transportation emissions cannot explain the missing and variable CO, which points to energy from buildings as a likely underappreciated source of urban air pollution and greenhouse gas emissions.
Chengzhi Xing, Cheng Liu, Chunxiang Ye, Jingkai Xue, Hongyu Wu, Xiangguang Ji, Jinping Ou, and Qihou Hu
Atmos. Chem. Phys., 24, 10093–10112, https://doi.org/10.5194/acp-24-10093-2024, https://doi.org/10.5194/acp-24-10093-2024, 2024
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We identified the contributions of ozone (O3) and nitrous acid (HONO) to the production rates of hydroxide (OH) in vertical space on the Tibetan Plateau (TP). A new insight was offered: the contributions of HONO and O3 to the production rates of OH on the TP are even greater than in lower-altitudes areas. This study enriches the understanding of vertical distribution of atmospheric components and explains the strong atmospheric oxidation capacity (AOC) on the TP.
Baoye Hu, Naihua Chen, Rui Li, Mingqiang Huang, Jinsheng Chen, Youwei Hong, Lingling Xu, Xiaolong Fan, Mengren Li, Lei Tong, Qiuping Zheng, and Yuxiang Yang
EGUsphere, https://doi.org/10.5194/egusphere-2024-2631, https://doi.org/10.5194/egusphere-2024-2631, 2024
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Box modeling with the master chemical mechanism (MCM) was used to address the puzzle of summertime PAN formation and its association with aerosol pollution under high ozone conditions. The MCM model proves to be an ideal tool for investigating PAN photochemical formation (IOA=0.75). The model performed better during the clean period than during the haze period. Through the machine learning method of XGBoost, we found that the top three factors leading to simulation bias were NH3, NO3, and PM2.5.
Xinyuan Zhang, Lingling Wang, Nan Wang, Shuangliang Ma, Shenbo Wang, Ruiqin Zhang, Dong Zhang, Mingkai Wang, and Hongyu Zhang
Atmos. Chem. Phys., 24, 9885–9898, https://doi.org/10.5194/acp-24-9885-2024, https://doi.org/10.5194/acp-24-9885-2024, 2024
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This study highlights the importance of the redox reaction of NO2 with SO2 based on actual atmospheric observations. The particle pH in future China is expected to rise steadily. Consequently, this reaction could become a significant source of HONO in China. Therefore, it is crucial to coordinate the control of SO2, NOx, and NH3 emissions to avoid a rapid increase in the particle pH.
Jun Zhou, Chunsheng Zhang, Aiming Liu, Bin Yuan, Yan Wang, Wenjie Wang, Jie-Ping Zhou, Yixin Hao, Xiao-Bing Li, Xianjun He, Xin Song, Yubin Chen, Suxia Yang, Shuchun Yang, Yanfeng Wu, Bin Jiang, Shan Huang, Junwen Liu, Yuwen Peng, Jipeng Qi, Minhui Deng, Bowen Zhong, Yibo Huangfu, and Min Shao
Atmos. Chem. Phys., 24, 9805–9826, https://doi.org/10.5194/acp-24-9805-2024, https://doi.org/10.5194/acp-24-9805-2024, 2024
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In-depth understanding of the near-ground vertical variability in photochemical ozone (O3) formation is crucial for mitigating O3 pollution. Utilizing a self-built vertical observation system, a direct net photochemical O3 production rate detection system, and an observation-based model, we diagnosed the vertical distributions and formation mechanism of net photochemical O3 production rates and sensitivity in the Pearl River Delta region, one of the most O3-polluted areas in China.
Eleanor J. Derry, Tyler R. Elgiar, Taylor Y. Wilmot, Nicholas W. Hoch, Noah S. Hirshorn, Peter Weiss-Penzias, Christopher F. Lee, John C. Lin, A. Gannet Hallar, Rainer Volkamer, Seth N. Lyman, and Lynne E. Gratz
Atmos. Chem. Phys., 24, 9615–9643, https://doi.org/10.5194/acp-24-9615-2024, https://doi.org/10.5194/acp-24-9615-2024, 2024
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Mercury (Hg) is a globally distributed neurotoxic pollutant. Atmospheric deposition is the main source of Hg in ecosystems. However, measurement biases hinder understanding of the origins and abundance of the more bioavailable oxidized form. We used an improved, calibrated measurement system to study air mass composition and transport of atmospheric Hg at a remote mountaintop site in the central US. Oxidized Hg originated upwind in the low to middle free troposphere under clean, dry conditions.
Benjamin A. Nault, Katherine R. Travis, James H. Crawford, Donald R. Blake, Pedro Campuzano-Jost, Ronald C. Cohen, Joshua P. DiGangi, Glenn S. Diskin, Samuel R. Hall, L. Gregory Huey, Jose L. Jimenez, Kyung-Eun Min, Young Ro Lee, Isobel J. Simpson, Kirk Ullmann, and Armin Wisthaler
Atmos. Chem. Phys., 24, 9573–9595, https://doi.org/10.5194/acp-24-9573-2024, https://doi.org/10.5194/acp-24-9573-2024, 2024
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Ozone (O3) is a pollutant formed from the reactions of gases emitted from various sources. In urban areas, the density of human activities can increase the O3 formation rate (P(O3)), thus impacting air quality and health. Observations collected over Seoul, South Korea, are used to constrain P(O3). A high local P(O3) was found; however, local P(O3) was partly reduced due to compounds typically ignored. These observations also provide constraints for unmeasured compounds that will impact P(O3).
Fan Zhang, Binyu Xiao, Zeyu Liu, Yan Zhang, Chongguo Tian, Rui Li, Can Wu, Yali Lei, Si Zhang, Xinyi Wan, Yubao Chen, Yong Han, Min Cui, Cheng Huang, Hongli Wang, Yingjun Chen, and Gehui Wang
Atmos. Chem. Phys., 24, 8999–9017, https://doi.org/10.5194/acp-24-8999-2024, https://doi.org/10.5194/acp-24-8999-2024, 2024
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Mandatory use of low-sulfur fuel due to global sulfur limit regulations means large uncertainties in volatile organic compound (VOC) emissions. On-board tests of VOCs from nine cargo ships in China were carried out. Results showed that switching from heavy-fuel oil to diesel increased emission factor VOCs by 48 % on average, enhancing O3 and the secondary organic aerosol formation potential. Thus, implementing a global ultra-low-sulfur oil policy needs to be optimized in the near future.
Patrick Dewald, Tobias Seubert, Simone T. Andersen, Gunther N. T. E. Türk, Jan Schuladen, Max R. McGillen, Cyrielle Denjean, Jean-Claude Etienne, Olivier Garrouste, Marina Jamar, Sergio Harb, Manuela Cirtog, Vincent Michoud, Mathieu Cazaunau, Antonin Bergé, Christopher Cantrell, Sebastien Dusanter, Bénédicte Picquet-Varrault, Alexandre Kukui, Chaoyang Xue, Abdelwahid Mellouki, Jos Lelieveld, and John N. Crowley
Atmos. Chem. Phys., 24, 8983–8997, https://doi.org/10.5194/acp-24-8983-2024, https://doi.org/10.5194/acp-24-8983-2024, 2024
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In the scope of a field campaign in a suburban forest near Paris in the summer of 2022, we measured the reactivity of the nitrate radical NO3 towards biogenic volatile organic compounds (BVOCs; e.g. monoterpenes) mainly below but also above the canopy. NO3 reactivity was the highest during nights with strong temperature inversions and decreased strongly with height. Reactions with BVOCs were the main removal process of NO3 throughout the diel cycle below the canopy.
Jian Wang, Lei Xue, Qianyao Ma, Feng Xu, Gaobin Xu, Shibo Yan, Jiawei Zhang, Jianlong Li, Honghai Zhang, Guiling Zhang, and Zhaohui Chen
Atmos. Chem. Phys., 24, 8721–8736, https://doi.org/10.5194/acp-24-8721-2024, https://doi.org/10.5194/acp-24-8721-2024, 2024
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This study investigated the distribution and sources of non-methane hydrocarbons (NMHCs) in the lower atmosphere over the marginal seas of China. NMHCs, a subset of volatile organic compounds (VOCs), play a crucial role in atmospheric chemistry. Derived from systematic atmospheric sampling in coastal cities and marginal sea regions, this study offers valuable insights into the interaction between land and sea in shaping offshore atmospheric NMHCs.
Yusheng Zhang, Feixue Zheng, Zemin Feng, Chaofan Lian, Weigang Wang, Xiaolong Fan, Wei Ma, Zhuohui Lin, Chang Li, Gen Zhang, Chao Yan, Ying Zhang, Veli-Matti Kerminen, Federico Bianch, Tuukka Petäjä, Juha Kangasluoma, Markku Kulmala, and Yongchun Liu
Atmos. Chem. Phys., 24, 8569–8587, https://doi.org/10.5194/acp-24-8569-2024, https://doi.org/10.5194/acp-24-8569-2024, 2024
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The nitrous acid (HONO) budget was validated during a COVID-19 lockdown event. The main conclusions are (1) HONO concentrations showed a significant decrease from 0.97 to 0.53 ppb during lockdown; (2) vehicle emissions accounted for 53 % of nighttime sources, with the heterogeneous conversion of NO2 on ground surfaces more important than aerosol; and (3) the dominant daytime source shifted from the homogenous reaction between NO and OH (51 %) to nitrate photolysis (53 %) during lockdown.
Dong Zhang, Xiao Li, Minghao Yuan, Yifei Xu, Qixiang Xu, Fangcheng Su, Shenbo Wang, and Ruiqin Zhang
Atmos. Chem. Phys., 24, 8549–8567, https://doi.org/10.5194/acp-24-8549-2024, https://doi.org/10.5194/acp-24-8549-2024, 2024
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The increasing concentration of O3 precursors and unfavorable meteorological conditions are key factors in the formation of O3 pollution in Zhengzhou. Vehicular exhausts (28 %), solvent usage (27 %), and industrial production (22 %) are identified as the main sources of NMVOCs. Moreover, O3 formation in Zhengzhou is found to be in an anthropogenic volatile organic compound (AVOC)-limited regime. Thus, to reduce O3 formation, a minimum AVOCs / NOx reduction ratio ≥ 3 : 1 is recommended.
Delaney B. Kilgour, Christopher M. Jernigan, Olga Garmash, Sneha Aggarwal, Claudia Mohr, Matt E. Salter, Joel A. Thornton, Jian Wang, Paul Zieger, and Timothy H. Bertram
EGUsphere, https://doi.org/10.5194/egusphere-2024-1975, https://doi.org/10.5194/egusphere-2024-1975, 2024
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We report simultaneous measurements of dimethyl sulfide (DMS) and hydroperoxymethyl thioformate (HPMTF) in the Eastern North Atlantic. We use an observationally constrained box model to show cloud loss is the dominant sink of HPMTF in this region over six weeks, resulting in large reductions in DMS-derived products that contribute to aerosol formation and growth. Our findings indicate that fast cloud processing of HPMTF must be included in global models to accurately capture the sulfur cycle.
Arianna Peron, Martin Graus, Marcus Striednig, Christian Lamprecht, Georg Wohlfahrt, and Thomas Karl
Atmos. Chem. Phys., 24, 7063–7083, https://doi.org/10.5194/acp-24-7063-2024, https://doi.org/10.5194/acp-24-7063-2024, 2024
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The anthropogenic fraction of non-methane volatile organic compound (NMVOC) emissions associated with biogenic sources (e.g., terpenes) is investigated based on eddy covariance observations. The anthropogenic fraction of terpene emissions is strongly dependent on season. When analyzing volatile chemical product (VCP) emissions in urban environments, we caution that observations from short-term campaigns might over-/underestimate their significance depending on local and seasonal circumstances.
Sihang Wang, Bin Yuan, Xianjun He, Ru Cui, Xin Song, Yubin Chen, Caihong Wu, Chaomin Wang, Yibo Huangfu, Xiao-Bing Li, Boguang Wang, and Min Shao
Atmos. Chem. Phys., 24, 7101–7121, https://doi.org/10.5194/acp-24-7101-2024, https://doi.org/10.5194/acp-24-7101-2024, 2024
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Emissions of reactive organic gases from industrial volatile chemical product sources are measured. There are large differences among these industrial sources. We show that oxygenated species account for significant contributions to reactive organic gas emissions, especially for industrial sources utilizing water-borne chemicals.
Qing Yang, Xiao-Bing Li, Bin Yuan, Xiaoxiao Zhang, Yibo Huangfu, Lei Yang, Xianjun He, Jipeng Qi, and Min Shao
Atmos. Chem. Phys., 24, 6865–6882, https://doi.org/10.5194/acp-24-6865-2024, https://doi.org/10.5194/acp-24-6865-2024, 2024
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Online vertical gradient measurements of formic and isocyanic acids were made based on a 320 m tower in a megacity. Vertical variations and sources of the two acids were analyzed in this study. We find that formic and isocyanic acids exhibited positive vertical gradients and were mainly contributed by photochemical formations. The formation of formic and isocyanic acids was also significantly enhanced in urban regions aloft.
Junwei Song, Harald Saathoff, Feng Jiang, Linyu Gao, Hengheng Zhang, and Thomas Leisner
Atmos. Chem. Phys., 24, 6699–6717, https://doi.org/10.5194/acp-24-6699-2024, https://doi.org/10.5194/acp-24-6699-2024, 2024
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This study presents concurrent online measurements of organic gas and particles (VOCs and OA) at a forested site in summer. Both VOCs and OA were largely contributed by oxygenated organic compounds. Semi-volatile oxygenated OA and organic nitrate formed from monoterpenes and sesquiterpenes contributed significantly to nighttime particle growth. The results help us to understand the causes of nighttime particle growth regularly observed in summer in central European rural forested environments.
Jiemeng Bao, Xin Zhang, Zhenhai Wu, Li Zhou, Jun Qian, Qinwen Tan, Fumo Yang, Junhui Chen, Yunfeng Li, Hefan Liu, Liqun Deng, and Hong Li
EGUsphere, https://doi.org/10.5194/egusphere-2024-1204, https://doi.org/10.5194/egusphere-2024-1204, 2024
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Our research in the Chengdu Plain Urban Agglomeration (CPUA), China, reveals significant correlations between carbonyl compounds and ozone pollution, particularly in Chengdu. Formaldehyde, acetone, and acetaldehyde are key contributors to ozone formation. Urgent collaborative actions among cities are needed to mitigate carbonyl-related ozone pollution, stressing the control of NOx and VOCs emissions. Our study offers crucial insights for crafting effective regional pollution control strategies.
Xin Yang, Kimberly Strong, Alison S. Criscitiello, Marta Santos-Garcia, Kristof Bognar, Xiaoyi Zhao, Pierre Fogal, Kaley A. Walker, Sara M. Morris, and Peter Effertz
Atmos. Chem. Phys., 24, 5863–5886, https://doi.org/10.5194/acp-24-5863-2024, https://doi.org/10.5194/acp-24-5863-2024, 2024
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This study uses snow samples collected from a Canadian high Arctic site, Eureka, to demonstrate that surface snow in early spring is a net sink of atmospheric bromine and nitrogen. Surface snow bromide and nitrate are significantly correlated, indicating the oxidation of reactive nitrogen is accelerated by reactive bromine. In addition, we show evidence that snow photochemical release of reactive bromine is very weak, and its emission flux is much smaller than the deposition flux of bromide.
Rebecca M. Garland, Katye E. Altieri, Laura Dawidowski, Laura Gallardo, Aderiana Mbandi, Nestor Y. Rojas, and N'datchoh E. Touré
Atmos. Chem. Phys., 24, 5757–5764, https://doi.org/10.5194/acp-24-5757-2024, https://doi.org/10.5194/acp-24-5757-2024, 2024
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This opinion piece focuses on two geographical areas in the Global South where the authors are based that are underrepresented in atmospheric science. This opinion provides context on common challenges and constraints, with suggestions on how the community can address these. The focus is on the strengths of atmospheric science research in these regions. It is these strengths, we believe, that highlight the critical role of Global South researchers in the future of atmospheric science research.
Heidi Hellén, Rostislav Kouznetsov, Kaisa Kraft, Jukka Seppälä, Mika Vestenius, Jukka-Pekka Jalkanen, Lauri Laakso, and Hannele Hakola
Atmos. Chem. Phys., 24, 4717–4731, https://doi.org/10.5194/acp-24-4717-2024, https://doi.org/10.5194/acp-24-4717-2024, 2024
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Mixing ratios of C2-C5 NMHCs and methanethiol were measured on an island in the Baltic Sea using an in situ gas chromatograph. Shipping emissions were found to be an important source of ethene, ethyne, propene, and benzene. High summertime mixing ratios of methanethiol and dependence of mixing ratios on seawater temperature and height indicated the biogenic origin to possibly be phytoplankton or macroalgae. These emissions may have a strong impact on SO2 production and new particle formation.
Matthew M. Coggon, Chelsea E. Stockwell, Lu Xu, Jeff Peischl, Jessica B. Gilman, Aaron Lamplugh, Henry J. Bowman, Kenneth Aikin, Colin Harkins, Qindan Zhu, Rebecca H. Schwantes, Jian He, Meng Li, Karl Seltzer, Brian McDonald, and Carsten Warneke
Atmos. Chem. Phys., 24, 4289–4304, https://doi.org/10.5194/acp-24-4289-2024, https://doi.org/10.5194/acp-24-4289-2024, 2024
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Residential and commercial cooking emits pollutants that degrade air quality. Here, ambient observations show that cooking is an important contributor to anthropogenic volatile organic compounds (VOCs) emitted in Las Vegas, NV. These emissions are not fully presented in air quality models, and more work may be needed to quantify emissions from important sources, such as commercial restaurants.
Fabien Paulot, Gabrielle Pétron, Andrew M. Crotwell, and Matteo B. Bertagni
Atmos. Chem. Phys., 24, 4217–4229, https://doi.org/10.5194/acp-24-4217-2024, https://doi.org/10.5194/acp-24-4217-2024, 2024
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New data from the National Oceanic and Atmospheric Administration show that hydrogen (H2) concentrations increased from 2010 to 2019, which is consistent with the simulated increase in H2 photochemical production (mainly from methane). But this cannot be reconciled with the expected decrease (increase) in H2 anthropogenic emissions (soil deposition) in the same period. This shows gaps in our knowledge of the H2 biogeochemical cycle that must be resolved to quantify the impact of higher H2 usage.
Wenjie Wang, Bin Yuan, Hang Su, Yafang Cheng, Jipeng Qi, Sihang Wang, Wei Song, Xinming Wang, Chaoyang Xue, Chaoqun Ma, Fengxia Bao, Hongli Wang, Shengrong Lou, and Min Shao
Atmos. Chem. Phys., 24, 4017–4027, https://doi.org/10.5194/acp-24-4017-2024, https://doi.org/10.5194/acp-24-4017-2024, 2024
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This study investigates the important role of unmeasured volatile organic compounds (VOCs) in ozone formation. Based on results in a megacity of China, we show that unmeasured VOCs can contribute significantly to ozone fomation and also influence the determination of ozone control strategy. Our results show that these unmeasured VOCs are mainly from human sources.
Shigeyuki Ishidoya, Satoshi Sugawara, and Atsushi Okazaki
EGUsphere, https://doi.org/10.5194/egusphere-2024-654, https://doi.org/10.5194/egusphere-2024-654, 2024
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Diurnal, seasonal, and interannual variations of the present-day stable isotopic ratio of atmospheric O2, in other words slight variations in the Dole-Morita effect, have been detected firstly. A box model that incorporated biological and water processes associated with the Dole-Morita effect reproduced the general characteristics of the observational results. Based on the findings, we proposed some applications to evaluate oxygen, carbon, and water cycles.
Romain Salignat, Matti Rissanen, Siddharth Iyer, Jean-Luc Baray, Pierre Tulet, Jean-Marc Metzger, Jérôme Brioude, Karine Sellegri, and Clémence Rose
Atmos. Chem. Phys., 24, 3785–3812, https://doi.org/10.5194/acp-24-3785-2024, https://doi.org/10.5194/acp-24-3785-2024, 2024
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Using mass spectrometry data collected at the Maïdo Observatory (2160 m a.s.l., Réunion), we provide the first detailed analysis of molecular cluster chemical composition specifically in the marine free troposphere. The abundance of the identified species is related both to in situ meteorological parameters and air mass history, which also provide insight into their origin. Our work makes an important contribution to documenting the chemistry and physics of the marine free troposphere.
Delaney B. Kilgour, Gordon A. Novak, Megan S. Claflin, Brian M. Lerner, and Timothy H. Bertram
Atmos. Chem. Phys., 24, 3729–3742, https://doi.org/10.5194/acp-24-3729-2024, https://doi.org/10.5194/acp-24-3729-2024, 2024
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Laboratory experiments with seawater mimics suggest ozone deposition to the surface ocean can be a source of reactive carbon to the marine atmosphere. We conduct both field and laboratory measurements to assess abiotic VOC composition and yields from ozonolysis of real surface seawater. We show that C5–C11 aldehydes contribute to the observed VOC emission flux. We estimate that VOCs generated by the ozonolysis of surface seawater are competitive with biological VOC production and emission.
Xiangdong Zheng, Wen Yang, Yuting Sun, Chunmei Geng, Yingying Liu, and Xiaobin Xu
Atmos. Chem. Phys., 24, 3759–3768, https://doi.org/10.5194/acp-24-3759-2024, https://doi.org/10.5194/acp-24-3759-2024, 2024
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Chen et al. (2022) attributed the nocturnal ozone enhancement (NOE) during the night of 31 July 2021 in the North China Plain (NCP) to "the direct stratospheric intrusion to reach the surface". We analyzed in situ data from the NCP. Our results do not suggest that there was a significant impact from the stratosphere on surface ozone during the NOE. We argue that the NOE was not caused by stratospheric intrusion but originated from fresh photochemical production in the lower troposphere.
Junling Li, Chaofan Lian, Mingyuan Liu, Hao Zhang, Yongxin Yan, Yufei Song, Chun Chen, Haijie Zhang, Yanqin Ren, Yucong Guo, Weigang Wang, Yisheng Xu, Hong Li, Jian Gao, and Maofa Ge
EGUsphere, https://doi.org/10.5194/egusphere-2024-367, https://doi.org/10.5194/egusphere-2024-367, 2024
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In recent years, the concentration of atmospheric particulate matter in China decreased significantly, but the ozone concentration showed a fluctuating upward trend, the atmospheric oxidation capacity increased significantly, especially in the warm season. Given the contribution of HONO to atmospheric oxidation capacity, its sources should be studied in more detail.
James M. Roberts, Siyuan Wang, Patrick R. Veres, J. Andrew Neuman, Michael A. Robinson, Ilann Bourgeois, Jeff Peischl, Thomas B. Ryerson, Chelsea R. Thompson, Hannah M. Allen, John D. Crounse, Paul O. Wennberg, Samuel R. Hall, Kirk Ullmann, Simone Meinardi, Isobel J. Simpson, and Donald Blake
Atmos. Chem. Phys., 24, 3421–3443, https://doi.org/10.5194/acp-24-3421-2024, https://doi.org/10.5194/acp-24-3421-2024, 2024
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We measured cyanogen bromide (BrCN) in the troposphere for the first time. BrCN is a product of the same active bromine chemistry that destroys ozone and removes mercury in polar surface environments and is a previously unrecognized sink for active Br compounds. BrCN has an apparent lifetime against heterogeneous loss in the range 1–10 d, so it serves as a cumulative marker of Br-radical chemistry. Accounting for BrCN chemistry is an important part of understanding polar Br cycling.
Kai Qin, Wei Hu, Qin He, Fan Lu, and Jason Blake Cohen
Atmos. Chem. Phys., 24, 3009–3028, https://doi.org/10.5194/acp-24-3009-2024, https://doi.org/10.5194/acp-24-3009-2024, 2024
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We compute CH4 emissions and uncertainty on a mine-by-mine basis, including underground, overground, and abandoned mines. Mine-by-mine gas and flux data and 30 min observations from a flux tower located next to a mine shaft are integrated. The observed variability and bias correction are propagated over the emissions dataset, demonstrating that daily observations may not cover the range of variability. Comparisons show both an emissions magnitude and spatial mismatch with current inventories.
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Short summary
This study reports the first flaring in situ measurements in southern West Africa. According to the measurements, oil rig flaring plumes in Ghana lead to increases in NO2 and aerosols but not always in CO and not in SO2. Flaring measurements can be reproduced using FLEXPART model, adjusting both the emission flux and the injection height. The DACCIWA satellite flaring inventory provides a reasonable estimate of flaring emission.
This study reports the first flaring in situ measurements in southern West Africa. According to...
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