Articles | Volume 14, issue 7
https://doi.org/10.5194/acp-14-3557-2014
© Author(s) 2014. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
https://doi.org/10.5194/acp-14-3557-2014
© Author(s) 2014. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Research article
| 
08 Apr 2014
Research article |
| 08 Apr 2014
Very short-lived bromomethanes measured by the CARIBIC observatory over the North Atlantic, Africa and Southeast Asia during 2009–2013
A. Wisher
Centre for Ocean and Atmospheric Sciences (COAS), School of Environmental Sciences, University of East Anglia, Norwich, NR4 7TJ, UK
D. E. Oram
National Center for Atmospheric Science (NCAS), Centre for Ocean and Atmospheric Sciences (COAS), School of Environmental Sciences, University of East Anglia, Norwich, NR4 7TJ, UK
J. C. Laube
Centre for Ocean and Atmospheric Sciences (COAS), School of Environmental Sciences, University of East Anglia, Norwich, NR4 7TJ, UK
G. P. Mills
Centre for Ocean and Atmospheric Sciences (COAS), School of Environmental Sciences, University of East Anglia, Norwich, NR4 7TJ, UK
P. van Velthoven
Royal Netherlands Meteorological Institute (KNMI), P.O. Box 201, 3730 AE, de Bilt, the Netherlands
A. Zahn
Karlsruhe Institute of Technology-Atmospheric Trace Gases and Remote Sensing (IMK-ASF), Postfach 36 40, 76021, Karlsruhe, Germany
C. A. M. Brenninkmeijer
Max Planck Institute for Chemistry, Air Chemistry Division, Hahn-Meitner Weg 1, 55128, Mainz, Germany
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Tanja J. Schuck, Johannes Degen, Timo Keber, Katharina Meixner, Thomas Wagenhäuser, Mélanie Ghysels, Georges Durry, Nadir Amarouche, Alessandro Zanchetta, Steven van Heuven, Huilin Chen, Johannes C. Laube, Sophie Baartman, Carina van der Veen, Maria Elena Popa, and Andreas Engel
EGUsphere, https://doi.org/10.5194/egusphere-2024-3279, https://doi.org/10.5194/egusphere-2024-3279, 2024
This preprint is open for discussion and under review for Atmospheric Chemistry and Physics (ACP).
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A balloon was launched in 2021 in the Arctic to carry instruments for trace gase measurements up to 32 km. One purpose was to compare measurement techniques. We focus on the major greenhouse gases. To measure these, air was sampled with the AirCore technique and with flask sampling and analysed after the flight. In flight, observations were done with an optical method. In a companion paper we report on observations of chlorine and bromine containing trace gases.
Randall Chiu, Florian Obersteiner, Alessandro Franchin, Teresa Campos, Adriana Bailey, Christopher Webster, Andreas Zahn, and Rainer Volkamer
Atmos. Meas. Tech., 17, 5731–5746, https://doi.org/10.5194/amt-17-5731-2024, https://doi.org/10.5194/amt-17-5731-2024, 2024
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The ozone sink into oceans and marine clouds is seldom studied and highly uncertain. Calculations suggest O3 destruction at aqueous surfaces (ocean, droplets) may be strongly accelerated, but field evidence is missing. Here we compare three fast airborne O3 instruments to measure eddy covariance fluxes of O3 over the remote ocean, in clear and cloudy air. We find O3 fluxes below clouds are consistently directed into clouds, while O3 fluxes into oceans are much smaller and spatially variable.
Florian Voet, Felix Plöger, Johannes Laube, Peter Preusse, Paul Konopka, Jens-Uwe Grooß, Jörn Ungermann, Björn-Martin Sinnhuber, Michael Hoepfner, Bernd Funke, Gerald Wetzel, Sören Johansson, Gabriele Stiller, Eric Ray, and Michaela Imelda Hegglin
EGUsphere, https://doi.org/10.5194/egusphere-2024-2624, https://doi.org/10.5194/egusphere-2024-2624, 2024
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This study refines estimates of the stratospheric “age of air,” a measure of how long air circulates in the stratosphere. By analyzing correlations between trace gases measurable by satellites, the research introduces a method that reduces uncertainties and detects small-scale atmospheric features. This improved understanding of stratospheric circulation is crucial for better climate models and predictions, enhancing our ability to assess the impacts of climate change on the atmosphere.
Patrick Konjari, Christian Rolf, Michaela Imelda Hegglin, Susanne Rohs, Yun Li, Andreas Zahn, Harald Bönisch, Martina Krämer, and Andreas Petzold
EGUsphere, https://doi.org/10.5194/egusphere-2024-2360, https://doi.org/10.5194/egusphere-2024-2360, 2024
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This study introduces a new method to deriving adjusted water vapor (H2O) climatologies for the upper tropopshere and lower statosphere (UT/LS) using data from 60,000 flights under the IAGOS program. Biases in the IAGOS water vapor dataset are adjusted, based on the more accurate IAGOS-CARIBIC data. The resulting highly resolved H2O climatologies will contribute to a better understanding of the H2O variability in the UT/LS and its connection to various transport and mixing processes.
Yann Cohen, Didier Hauglustaine, Nicolas Bellouin, Marianne Tronstad Lund, Sigrun Matthes, Agnieszka Skowron, Robin Thor, Ulrich Bundke, Andreas Petzold, Susanne Rohs, Valérie Thouret, Andreas Zahn, and Helmut Ziereis
EGUsphere, https://doi.org/10.5194/egusphere-2024-2208, https://doi.org/10.5194/egusphere-2024-2208, 2024
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The chemical composition of the atmosphere near the tropopause is a key parameter for evaluating the climate impact of subsonic aviation pollutants. This study uses in-situ data on board passenger aircraft to assess the ability of 5 chemistry-climate models to reproduce (bi-)decadal climatologies in ozone, carbon monoxide, water vapour, and reactive nitrogen in this region. The models reproduce well the very distinct ozone seasonality in the upper troposphere and in the lower stratosphere.
Laura N. Saunders, Kaley A. Walker, Gabriele P. Stiller, Thomas von Clarmann, Florian Haenel, Hella Garny, Harald Bönisch, Chris D. Boone, Ariana E. Castillo, Andreas Engel, Johannes C. Laube, Marianna Linz, Felix Ploeger, David A. Plummer, Eric A. Ray, and Patrick E. Sheese
EGUsphere, https://doi.org/10.5194/egusphere-2024-2117, https://doi.org/10.5194/egusphere-2024-2117, 2024
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We present a 17-year stratospheric age of air dataset derived from ACE-FTS satellite measurements of sulfur hexafluoride. This is the longest continuous, global, and vertically resolved age of air time series available to date. In this paper, we show that this dataset agrees well with age of air datasets based on measurements from other instruments. We also present trends in the midlatitude lower stratosphere that indicate changes in the global circulation that are predicted by climate models.
Philipp Joppe, Johannes Schneider, Katharina Kaiser, Horst Fischer, Peter Hoor, Daniel Kunkel, Hans-Christoph Lachnitt, Andreas Marsing, Lenard Röder, Hans Schlager, Laura Tomsche, Christiane Voigt, Andreas Zahn, and Stephan Borrmann
Atmos. Chem. Phys., 24, 7499–7522, https://doi.org/10.5194/acp-24-7499-2024, https://doi.org/10.5194/acp-24-7499-2024, 2024
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From aircraft measurements in the upper troposphere/lower stratosphere, we find a correlation between the ozone and particulate sulfate in the lower stratosphere. The correlation exhibits some variability over the measurement period exceeding the background sulfate-to-ozone correlation. From our analysis, we conclude that gas-to-particle conversion of volcanic sulfur dioxide leads to observed enhanced sulfate aerosol mixing ratios.
Hella Garny, Roland Eichinger, Johannes C. Laube, Eric A. Ray, Gabriele P. Stiller, Harald Bönisch, Laura Saunders, and Marianna Linz
Atmos. Chem. Phys., 24, 4193–4215, https://doi.org/10.5194/acp-24-4193-2024, https://doi.org/10.5194/acp-24-4193-2024, 2024
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Transport circulation in the stratosphere is important for the distribution of tracers, but its strength is hard to measure. Mean transport times can be inferred from observations of trace gases with certain properties, such as sulfur hexafluoride (SF6). However, this gas has a chemical sink in the high atmosphere, which can lead to substantial biases in inferred transport times. In this paper we present a method to correct mean transport times derived from SF6 for the effects of chemical sinks.
Tanja J. Schuck, Johannes Degen, Eric Hintsa, Peter Hoor, Markus Jesswein, Timo Keber, Daniel Kunkel, Fred Moore, Florian Obersteiner, Matt Rigby, Thomas Wagenhäuser, Luke M. Western, Andreas Zahn, and Andreas Engel
Atmos. Chem. Phys., 24, 689–705, https://doi.org/10.5194/acp-24-689-2024, https://doi.org/10.5194/acp-24-689-2024, 2024
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We study the interhemispheric gradient of sulfur hexafluoride (SF6), a strong long-lived greenhouse gas. Its emissions are stronger in the Northern Hemisphere; therefore, mixing ratios in the Southern Hemisphere lag behind. Comparing the observations to a box model, the model predicts air in the Southern Hemisphere to be older. For a better agreement, the emissions used as model input need to be increased (and their spatial pattern changed), and we need to modify north–south transport.
Bärbel Vogel, C. Michael Volk, Johannes Wintel, Valentin Lauther, Jan Clemens, Jens-Uwe Grooß, Gebhard Günther, Lars Hoffmann, Johannes C. Laube, Rolf Müller, Felix Ploeger, and Fred Stroh
Atmos. Chem. Phys., 24, 317–343, https://doi.org/10.5194/acp-24-317-2024, https://doi.org/10.5194/acp-24-317-2024, 2024
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Over the Indian subcontinent, polluted air is rapidly uplifted to higher altitudes during the Asian monsoon season. We present an assessment of vertical transport in this region using different wind data provided by the European Centre for Medium-Range Weather Forecasts (ECMWF), as well as high-resolution aircraft measurements. In general, our findings confirm that the newest ECMWF reanalysis product, ERA5, yields a better representation of transport compared to the predecessor, ERA-Interim.
Yann Cohen, Didier Hauglustaine, Bastien Sauvage, Susanne Rohs, Patrick Konjari, Ulrich Bundke, Andreas Petzold, Valérie Thouret, Andreas Zahn, and Helmut Ziereis
Atmos. Chem. Phys., 23, 14973–15009, https://doi.org/10.5194/acp-23-14973-2023, https://doi.org/10.5194/acp-23-14973-2023, 2023
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The upper troposphere–lower stratosphere (UTLS) is a key region regarding the lower atmospheric composition. This study consists of a comprehensive evaluation of an up-to-date chemistry–climate model in this layer, using regular in situ measurements based on passenger aircraft. For this purpose, a specific software (Interpol-IAGOS) has been updated and made publicly available. The model reproduces the carbon monoxide peaks due to biomass burning over the continental tropics particularly well.
Midhun George, Maria Dolores Andrés Hernández, Vladyslav Nenakhov, Yangzhuoran Liu, John Philip Burrows, Birger Bohn, Eric Förster, Florian Obersteiner, Andreas Zahn, Theresa Harlaß, Helmut Ziereis, Hans Schlager, Benjamin Schreiner, Flora Kluge, Katja Bigge, and Klaus Pfeilsticker
Atmos. Chem. Phys., 23, 7799–7822, https://doi.org/10.5194/acp-23-7799-2023, https://doi.org/10.5194/acp-23-7799-2023, 2023
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The applicability of photostationary steady-state (PSS) assumptions to estimate the amount of the sum of peroxy radicals (RO2*) during the EMeRGe airborne observations from the known radical chemistry and onboard measurements of RO2* precursors, photolysis frequencies, and other trace gases such as NOx and O3 was investigated. The comparison of the calculated RO2* with the actual measurements provides an insight into the main processes controlling their concentration in the air masses measured.
Markus Kilian, Volker Grewe, Patrick Jöckel, Astrid Kerkweg, Mariano Mertens, Andreas Zahn, and Helmut Ziereis
EGUsphere, https://doi.org/10.5194/egusphere-2023-528, https://doi.org/10.5194/egusphere-2023-528, 2023
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Anthropogenic emissions are a major source of precursors for tropospheric ozone formation. As ozone formation is highly non-linear, we apply a global-regional chemistry-climate model with a source attribution method (tagging) to quantify the contribution of anthropogenic emissions to ozone. We focus on two major polluted areas in Europe, the Po Valley and the Benelux region. Our analysis shows that in particular anthropogenic emissions from Europe contribute largely to ground-level ozone.
Luis F. Millán, Gloria L. Manney, Harald Boenisch, Michaela I. Hegglin, Peter Hoor, Daniel Kunkel, Thierry Leblanc, Irina Petropavlovskikh, Kaley Walker, Krzysztof Wargan, and Andreas Zahn
Atmos. Meas. Tech., 16, 2957–2988, https://doi.org/10.5194/amt-16-2957-2023, https://doi.org/10.5194/amt-16-2957-2023, 2023
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The determination of atmospheric composition trends in the upper troposphere and lower stratosphere (UTLS) is still highly uncertain. We present the creation of dynamical diagnostics to map several ozone datasets (ozonesondes, lidars, aircraft, and satellite measurements) in geophysically based coordinate systems. The diagnostics can also be used to analyze other greenhouse gases relevant to surface climate and UTLS chemistry.
Eric Förster, Harald Bönisch, Marco Neumaier, Florian Obersteiner, Andreas Zahn, Andreas Hilboll, Anna B. Kalisz Hedegaard, Nikos Daskalakis, Alexandros Panagiotis Poulidis, Mihalis Vrekoussis, Michael Lichtenstern, and Peter Braesicke
Atmos. Chem. Phys., 23, 1893–1918, https://doi.org/10.5194/acp-23-1893-2023, https://doi.org/10.5194/acp-23-1893-2023, 2023
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The airborne megacity campaign EMeRGe provided an unprecedented amount of trace gas measurements. We combine measured volatile organic compounds (VOCs) with trajectory-modelled emission uptakes to identify potential source regions of pollution. We also characterise the chemical fingerprints (e.g. biomass burning and anthropogenic signatures) of the probed air masses to corroborate the contributing source regions. Our approach is the first large-scale study of VOCs originating from megacities.
Laura Tomsche, Andreas Marsing, Tina Jurkat-Witschas, Johannes Lucke, Stefan Kaufmann, Katharina Kaiser, Johannes Schneider, Monika Scheibe, Hans Schlager, Lenard Röder, Horst Fischer, Florian Obersteiner, Andreas Zahn, Martin Zöger, Jos Lelieveld, and Christiane Voigt
Atmos. Chem. Phys., 22, 15135–15151, https://doi.org/10.5194/acp-22-15135-2022, https://doi.org/10.5194/acp-22-15135-2022, 2022
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The detection of sulfur compounds in the upper troposphere (UT) and lower stratosphere (LS) is a challenge. In-flight measurements of SO2 and sulfate aerosol were performed during the BLUESKY mission in spring 2020 under exceptional atmospheric conditions. Reduced sinks in the dry UTLS and lower but still significant air traffic influenced the enhanced SO2 in the UT, and aged volcanic plumes enhanced the LS sulfate aerosol impacting the atmospheric radiation budget and global climate.
Paul Konopka, Mengchu Tao, Marc von Hobe, Lars Hoffmann, Corinna Kloss, Fabrizio Ravegnani, C. Michael Volk, Valentin Lauther, Andreas Zahn, Peter Hoor, and Felix Ploeger
Geosci. Model Dev., 15, 7471–7487, https://doi.org/10.5194/gmd-15-7471-2022, https://doi.org/10.5194/gmd-15-7471-2022, 2022
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Pure trajectory-based transport models driven by meteorology derived from reanalysis products (ERA5) take into account only the resolved, advective part of transport. That means neither mixing processes nor unresolved subgrid-scale advective processes like convection are included. The Chemical Lagrangian Model of the Stratosphere (CLaMS) includes these processes. We show that isentropic mixing dominates unresolved transport. The second most important transport process is unresolved convection.
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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In this work we use a combination of observational data from an aircraft campaign and model results to investigate the effect of the European lockdown due to COVID-19 in spring 2020. Using model results, we show that the largest relative changes to the atmospheric composition caused by the reduced emissions are located in the upper troposphere around aircraft cruise altitude, while the largest absolute changes are present at the surface.
Liubov Poshyvailo-Strube, Rolf Müller, Stephan Fueglistaler, Michaela I. Hegglin, Johannes C. Laube, C. Michael Volk, and Felix Ploeger
Atmos. Chem. Phys., 22, 9895–9914, https://doi.org/10.5194/acp-22-9895-2022, https://doi.org/10.5194/acp-22-9895-2022, 2022
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Brewer–Dobson circulation (BDC) controls the composition of the stratosphere, which in turn affects radiation and climate. As the BDC cannot be measured directly, it is necessary to infer its strength and trends indirectly. In this study, we test in the
model worlddifferent methods for estimating the mean age of air trends based on a combination of stratospheric water vapour and methane data. We also provide simple practical advice of a more reliable estimation of the mean age of air trends.
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
Atmos. Chem. Phys., 22, 5877–5924, https://doi.org/10.5194/acp-22-5877-2022, https://doi.org/10.5194/acp-22-5877-2022, 2022
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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.
Helmut Ziereis, Peter Hoor, Jens-Uwe Grooß, Andreas Zahn, Greta Stratmann, Paul Stock, Michael Lichtenstern, Jens Krause, Vera Bense, Armin Afchine, Christian Rolf, Wolfgang Woiwode, Marleen Braun, Jörn Ungermann, Andreas Marsing, Christiane Voigt, Andreas Engel, Björn-Martin Sinnhuber, and Hermann Oelhaf
Atmos. Chem. Phys., 22, 3631–3654, https://doi.org/10.5194/acp-22-3631-2022, https://doi.org/10.5194/acp-22-3631-2022, 2022
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Airborne observations were conducted in the lowermost Arctic stratosphere during the winter of 2015/2016. The observed distribution of reactive nitrogen shows clear indications of nitrification in mid-winter and denitrification in late winter. This was caused by the formation of polar stratospheric cloud particles, which were observed during several flights. The sedimentation and evaporation of these particles and the descent of air masses cause a redistribution of reactive nitrogen.
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
Preprint withdrawn
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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.
Meike K. Rotermund, Vera Bense, Martyn P. Chipperfield, Andreas Engel, Jens-Uwe Grooß, Peter Hoor, Tilman Hüneke, Timo Keber, Flora Kluge, Benjamin Schreiner, Tanja Schuck, Bärbel Vogel, Andreas Zahn, and Klaus Pfeilsticker
Atmos. Chem. Phys., 21, 15375–15407, https://doi.org/10.5194/acp-21-15375-2021, https://doi.org/10.5194/acp-21-15375-2021, 2021
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Airborne total bromine (Brtot) and tracer measurements suggest Brtot-rich air masses persistently protruded into the lower stratosphere (LS), creating a high Brtot region over the North Atlantic in fall 2017. The main source is via isentropic transport by the Asian monsoon and to a lesser extent transport across the extratropical tropopause as quantified by a Lagrange model. The transport of Brtot via Central American hurricanes is also observed. Lastly, the impact of Brtot on LS O3 is assessed.
Lukas Krasauskas, Jörn Ungermann, Peter Preusse, Felix Friedl-Vallon, Andreas Zahn, Helmut Ziereis, Christian Rolf, Felix Plöger, Paul Konopka, Bärbel Vogel, and Martin Riese
Atmos. Chem. Phys., 21, 10249–10272, https://doi.org/10.5194/acp-21-10249-2021, https://doi.org/10.5194/acp-21-10249-2021, 2021
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A Rossby wave (RW) breaking event was observed over the North Atlantic during the WISE measurement campaign in October 2017. Infrared limb sounding measurements of trace gases in the lower stratosphere, including high-resolution 3-D tomographic reconstruction, revealed complex spatial structures in stratospheric tracers near the polar jet related to previous RW breaking events. Backward-trajectory analysis and tracer correlations were used to study mixing and stratosphere–troposphere exchange.
Felix Ploeger, Mohamadou Diallo, Edward Charlesworth, Paul Konopka, Bernard Legras, Johannes C. Laube, Jens-Uwe Grooß, Gebhard Günther, Andreas Engel, and Martin Riese
Atmos. Chem. Phys., 21, 8393–8412, https://doi.org/10.5194/acp-21-8393-2021, https://doi.org/10.5194/acp-21-8393-2021, 2021
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We investigate the global stratospheric circulation (Brewer–Dobson circulation) in the new ECMWF ERA5 reanalysis based on age of air simulations, and we compare it to results from the preceding ERA-Interim reanalysis. Our results show a slower stratospheric circulation and higher age for ERA5. The age of air trend in ERA5 over the 1989–2018 period is negative throughout the stratosphere, related to multi-annual variability and a potential contribution from changes in the reanalysis system.
Romain Blot, Philippe Nedelec, Damien Boulanger, Pawel Wolff, Bastien Sauvage, Jean-Marc Cousin, Gilles Athier, Andreas Zahn, Florian Obersteiner, Dieter Scharffe, Hervé Petetin, Yasmine Bennouna, Hannah Clark, and Valérie Thouret
Atmos. Meas. Tech., 14, 3935–3951, https://doi.org/10.5194/amt-14-3935-2021, https://doi.org/10.5194/amt-14-3935-2021, 2021
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A lack of information about temporal changes in measurement uncertainties is an area of concern for long-term trend studies of the key compounds which have a direct or indirect impact on climate change. The IAGOS program has measured O3 and CO within the troposphere and lower stratosphere for more than 25 years. In this study, we demonstrated that the IAGOS database can be treated as one continuous program and is therefore appropriate for studies of long-term trends.
Max Thomas, Johannes C. Laube, Jan Kaiser, Samuel Allin, Patricia Martinerie, Robert Mulvaney, Anna Ridley, Thomas Röckmann, William T. Sturges, and Emmanuel Witrant
Atmos. Chem. Phys., 21, 6857–6873, https://doi.org/10.5194/acp-21-6857-2021, https://doi.org/10.5194/acp-21-6857-2021, 2021
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CFC gases are destroying the Earth's life-protecting ozone layer. We improve understanding of CFC destruction by measuring the isotopic fingerprint of the carbon in the three most abundant CFCs. These are the first such measurements in the main region where CFCs are destroyed – the stratosphere. We reconstruct the atmospheric isotope histories of these CFCs back to the 1950s by measuring air extracted from deep snow and using a model. The model and the measurements are generally consistent.
Claire E. Reeves, Graham P. Mills, Lisa K. Whalley, W. Joe F. Acton, William J. Bloss, Leigh R. Crilley, Sue Grimmond, Dwayne E. Heard, C. Nicholas Hewitt, James R. Hopkins, Simone Kotthaus, Louisa J. Kramer, Roderic L. Jones, James D. Lee, Yanhui Liu, Bin Ouyang, Eloise Slater, Freya Squires, Xinming Wang, Robert Woodward-Massey, and Chunxiang Ye
Atmos. Chem. Phys., 21, 6315–6330, https://doi.org/10.5194/acp-21-6315-2021, https://doi.org/10.5194/acp-21-6315-2021, 2021
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The impact of isoprene on atmospheric chemistry is dependent on how its oxidation products interact with other pollutants, specifically nitrogen oxides. Such interactions can lead to isoprene nitrates. We made measurements of the concentrations of individual isoprene nitrate isomers in Beijing and used a model to test current understanding of their chemistry. We highlight areas of uncertainty in understanding, in particular the chemistry following oxidation of isoprene by the nitrate radical.
Einar Karu, Mengze Li, Lisa Ernle, Carl A. M. Brenninkmeijer, Jos Lelieveld, and Jonathan Williams
Atmos. Meas. Tech., 14, 1817–1831, https://doi.org/10.5194/amt-14-1817-2021, https://doi.org/10.5194/amt-14-1817-2021, 2021
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A gas measurement device was developed to measure trace gases (ppt level) in the air based on an atomic emission detector. It combines a cryogenic pre-concentrator (CryoTrap), a gas chromatograph (GC), and a new high-resolution atomic emission detector (AED). The CryoTrap–GC–AED instrumental setup, limits of detection, and elemental performance are presented and discussed. Two measurement case studies are reported: one in a Finnish boreal forest and the other based on an aircraft campaign.
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.
Johannes C. Laube, Emma C. Leedham Elvidge, Karina E. Adcock, Bianca Baier, Carl A. M. Brenninkmeijer, Huilin Chen, Elise S. Droste, Jens-Uwe Grooß, Pauli Heikkinen, Andrew J. Hind, Rigel Kivi, Alexander Lojko, Stephen A. Montzka, David E. Oram, Steve Randall, Thomas Röckmann, William T. Sturges, Colm Sweeney, Max Thomas, Elinor Tuffnell, and Felix Ploeger
Atmos. Chem. Phys., 20, 9771–9782, https://doi.org/10.5194/acp-20-9771-2020, https://doi.org/10.5194/acp-20-9771-2020, 2020
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We demonstrate that AirCore technology, which is based on small low-cost balloons, can provide access to trace gas measurements such as CFCs at ultra-low abundances. This is a new way to quantify ozone-depleting, and related, substances in the stratosphere, which is largely inaccessible to aircraft. We show two potential uses: (a) tracking the stratospheric circulation, which is predicted to change, and (b) assessing three common meteorological reanalyses driving a global stratospheric model.
Peter H. Zimmermann, Carl A. M. Brenninkmeijer, Andrea Pozzer, Patrick Jöckel, Franziska Winterstein, Andreas Zahn, Sander Houweling, and Jos Lelieveld
Atmos. Chem. Phys., 20, 5787–5809, https://doi.org/10.5194/acp-20-5787-2020, https://doi.org/10.5194/acp-20-5787-2020, 2020
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The atmospheric abundance of the greenhouse gas methane is determined by interacting emission sources and sinks in a dynamic global environment. In this study, its global budget from 1997 to 2016 is simulated with a general circulation model using emission estimates of 11 source categories. The model results are evaluated against 17 ground station and 320 intercontinental flight observation series. Deviations are used to re-scale the emission quantities with the aim of matching observations.
Elise S. Droste, Karina E. Adcock, Matthew J. Ashfold, Charles Chou, Zoë Fleming, Paul J. Fraser, Lauren J. Gooch, Andrew J. Hind, Ray L. Langenfelds, Emma C. Leedham Elvidge, Norfazrin Mohd Hanif, Simon O'Doherty, David E. Oram, Chang-Feng Ou-Yang, Marios Panagi, Claire E. Reeves, William T. Sturges, and Johannes C. Laube
Atmos. Chem. Phys., 20, 4787–4807, https://doi.org/10.5194/acp-20-4787-2020, https://doi.org/10.5194/acp-20-4787-2020, 2020
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We update the tropospheric trends and emissions of six perfluorocarbon (PFC) gases, including separate isomers. Trends for these strong greenhouse gases are still increasing, but at slower rates than previously. The lack of natural sinks results in the global accumulation of 833 million metric tonnes of CO2 equivalent for these six PFCs by 2017. Modelling results indicate potential source regions and types in East Asia, but we find that many emissions are unaccounted for in emission reports.
Tanja J. Schuck, Ann-Katrin Blank, Elisa Rittmeier, Jonathan Williams, Carl A. M. Brenninkmeijer, Andreas Engel, and Andreas Zahn
Atmos. Meas. Tech., 13, 73–84, https://doi.org/10.5194/amt-13-73-2020, https://doi.org/10.5194/amt-13-73-2020, 2020
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Air sample collection aboard aircraft is a tool to measure atmospheric trace gas mixing ratios at altitude. We present results on the stability of 28 halocarbons during storage of air samples collected in stainless-steel flasks inside an automated air sampling unit which is part of the CARIBIC instrument package. Selected fluorinated compounds grew during the experiments while short-lived compounds were depleted. Individual substances were additionally influenced by high mixing ratios of ozone.
Zongbo Shi, Tuan Vu, Simone Kotthaus, Roy M. Harrison, Sue Grimmond, Siyao Yue, Tong Zhu, James Lee, Yiqun Han, Matthias Demuzere, Rachel E. Dunmore, Lujie Ren, Di Liu, Yuanlin Wang, Oliver Wild, James Allan, W. Joe Acton, Janet Barlow, Benjamin Barratt, David Beddows, William J. Bloss, Giulia Calzolai, David Carruthers, David C. Carslaw, Queenie Chan, Lia Chatzidiakou, Yang Chen, Leigh Crilley, Hugh Coe, Tie Dai, Ruth Doherty, Fengkui Duan, Pingqing Fu, Baozhu Ge, Maofa Ge, Daobo Guan, Jacqueline F. Hamilton, Kebin He, Mathew Heal, Dwayne Heard, C. Nicholas Hewitt, Michael Hollaway, Min Hu, Dongsheng Ji, Xujiang Jiang, Rod Jones, Markus Kalberer, Frank J. Kelly, Louisa Kramer, Ben Langford, Chun Lin, Alastair C. Lewis, Jie Li, Weijun Li, Huan Liu, Junfeng Liu, Miranda Loh, Keding Lu, Franco Lucarelli, Graham Mann, Gordon McFiggans, Mark R. Miller, Graham Mills, Paul Monk, Eiko Nemitz, Fionna O'Connor, Bin Ouyang, Paul I. Palmer, Carl Percival, Olalekan Popoola, Claire Reeves, Andrew R. Rickard, Longyi Shao, Guangyu Shi, Dominick Spracklen, David Stevenson, Yele Sun, Zhiwei Sun, Shu Tao, Shengrui Tong, Qingqing Wang, Wenhua Wang, Xinming Wang, Xuejun Wang, Zifang Wang, Lianfang Wei, Lisa Whalley, Xuefang Wu, Zhijun Wu, Pinhua Xie, Fumo Yang, Qiang Zhang, Yanli Zhang, Yuanhang Zhang, and Mei Zheng
Atmos. Chem. Phys., 19, 7519–7546, https://doi.org/10.5194/acp-19-7519-2019, https://doi.org/10.5194/acp-19-7519-2019, 2019
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APHH-Beijing is a collaborative international research programme to study the sources, processes and health effects of air pollution in Beijing. This introduction to the special issue provides an overview of (i) the APHH-Beijing programme, (ii) the measurement and modelling activities performed as part of it and (iii) the air quality and meteorological conditions during joint intensive field campaigns as a core activity within APHH-Beijing.
Johannes Eckstein, Roland Ruhnke, Stephan Pfahl, Emanuel Christner, Christopher Diekmann, Christoph Dyroff, Daniel Reinert, Daniel Rieger, Matthias Schneider, Jennifer Schröter, Andreas Zahn, and Peter Braesicke
Geosci. Model Dev., 11, 5113–5133, https://doi.org/10.5194/gmd-11-5113-2018, https://doi.org/10.5194/gmd-11-5113-2018, 2018
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We present ICON-ART-Iso, an extension to the global circulation model ICON, which allows for the simulation of the stable isotopologues of water. The main advantage over other isotope-enabled models is its flexible design with respect to the number of tracers simulated. We compare the results of several simulations to measurements of different scale. ICON-ART-Iso is able to reasonably reproduce the measurements. It is a promising tool to aid in the investigation of the atmospheric water cycle.
Franz Slemr, Andreas Weigelt, Ralf Ebinghaus, Johannes Bieser, Carl A. M. Brenninkmeijer, Armin Rauthe-Schöch, Markus Hermann, Bengt G. Martinsson, Peter van Velthoven, Harald Bönisch, Marco Neumaier, Andreas Zahn, and Helmut Ziereis
Atmos. Chem. Phys., 18, 12329–12343, https://doi.org/10.5194/acp-18-12329-2018, https://doi.org/10.5194/acp-18-12329-2018, 2018
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Total and elemental mercury were measured in the upper troposphere and lower stratosphere onboard a passenger aircraft. Their concentrations in the upper troposphere were comparable implying low concentrations of oxidized mercury in this region. Large scale seasonally dependent influence of emissions from biomass burning was also observed. Their distributions in the lower stratosphere implies a long stratospheric lifetime, which precludes significant mercury oxidation by ozone.
Sören Johansson, Wolfgang Woiwode, Michael Höpfner, Felix Friedl-Vallon, Anne Kleinert, Erik Kretschmer, Thomas Latzko, Johannes Orphal, Peter Preusse, Jörn Ungermann, Michelle L. Santee, Tina Jurkat-Witschas, Andreas Marsing, Christiane Voigt, Andreas Giez, Martina Krämer, Christian Rolf, Andreas Zahn, Andreas Engel, Björn-Martin Sinnhuber, and Hermann Oelhaf
Atmos. Meas. Tech., 11, 4737–4756, https://doi.org/10.5194/amt-11-4737-2018, https://doi.org/10.5194/amt-11-4737-2018, 2018
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We present two-dimensional cross sections of temperature, HNO3, O3, ClONO2, H2O and CFC-12 from measurements of the GLORIA infrared limb imager during the POLSTRACC/GW-LCYCLE/SALSA aircraft campaigns in the Arctic winter 2015/2016. GLORIA sounded the atmosphere between 5 and 14 km with vertical resolutions of 0.4–1 km. Estimated errors are in the range of 1–2 K (temperature) and 10 %–20 % (trace gases). Comparisons to in situ instruments onboard the aircraft and to Aura/MLS are shown.
Sergey Gromov, Carl A. M. Brenninkmeijer, and Patrick Jöckel
Atmos. Chem. Phys., 18, 9831–9843, https://doi.org/10.5194/acp-18-9831-2018, https://doi.org/10.5194/acp-18-9831-2018, 2018
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Using the observational data on 13C (CO) and 13C (CH4) from the extra-tropical Southern Hemisphere (ETSH) and EMAC model we (1) provide an independent, observation-based evaluation of Cl atom concentration variations in the ETSH throughout 1994–2000, (2) show that the role of tropospheric Cl as a sink of CH4 is seriously overestimated in the literature, (3) demonstrate that the 13C/12C ratio of CO is a sensitive indicator for the isotopic composition of reacted CH4 and therefore for its sources.
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.
Karina E. Adcock, Claire E. Reeves, Lauren J. Gooch, Emma C. Leedham Elvidge, Matthew J. Ashfold, Carl A. M. Brenninkmeijer, Charles Chou, Paul J. Fraser, Ray L. Langenfelds, Norfazrin Mohd Hanif, Simon O'Doherty, David E. Oram, Chang-Feng Ou-Yang, Siew Moi Phang, Azizan Abu Samah, Thomas Röckmann, William T. Sturges, and Johannes C. Laube
Atmos. Chem. Phys., 18, 4737–4751, https://doi.org/10.5194/acp-18-4737-2018, https://doi.org/10.5194/acp-18-4737-2018, 2018
Emma C. Leedham Elvidge, Harald Bönisch, Carl A. M. Brenninkmeijer, Andreas Engel, Paul J. Fraser, Eileen Gallacher, Ray Langenfelds, Jens Mühle, David E. Oram, Eric A. Ray, Anna R. Ridley, Thomas Röckmann, William T. Sturges, Ray F. Weiss, and Johannes C. Laube
Atmos. Chem. Phys., 18, 3369–3385, https://doi.org/10.5194/acp-18-3369-2018, https://doi.org/10.5194/acp-18-3369-2018, 2018
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Chemical species measured in stratospheric air can be used as proxies for stratospheric circulation changes which cannot be measured directly. A range of tracers is important to understand changing stratospheric dynamics. We demonstrate the suitability of PFCs and HFCs as tracers and support recent work that reduces the current stratospheric lifetime of SF6. Updates to policy-relevant parameters (e.g. stratospheric lifetime) linked to this change are provided for O3-depleting substances.
Taku Umezawa, Carl A. M. Brenninkmeijer, Thomas Röckmann, Carina van der Veen, Stanley C. Tyler, Ryo Fujita, Shinji Morimoto, Shuji Aoki, Todd Sowers, Jochen Schmitt, Michael Bock, Jonas Beck, Hubertus Fischer, Sylvia E. Michel, Bruce H. Vaughn, John B. Miller, James W. C. White, Gordon Brailsford, Hinrich Schaefer, Peter Sperlich, Willi A. Brand, Michael Rothe, Thomas Blunier, David Lowry, Rebecca E. Fisher, Euan G. Nisbet, Andrew L. Rice, Peter Bergamaschi, Cordelia Veidt, and Ingeborg Levin
Atmos. Meas. Tech., 11, 1207–1231, https://doi.org/10.5194/amt-11-1207-2018, https://doi.org/10.5194/amt-11-1207-2018, 2018
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Isotope measurements are useful for separating different methane sources. However, the lack of widely accepted standards and calibration methods for stable carbon and hydrogen isotopic ratios of methane in air has caused significant measurement offsets among laboratories. We conducted worldwide interlaboratory comparisons, surveyed the literature and assessed them systematically. This study may be of help in future attempts to harmonize data sets of isotopic composition of atmospheric methane.
Tilman Hüneke, Oliver-Alex Aderhold, Jannik Bounin, Marcel Dorf, Eric Gentry, Katja Grossmann, Jens-Uwe Grooß, Peter Hoor, Patrick Jöckel, Mareike Kenntner, Marvin Knapp, Matthias Knecht, Dominique Lörks, Sabrina Ludmann, Sigrun Matthes, Rasmus Raecke, Marcel Reichert, Jannis Weimar, Bodo Werner, Andreas Zahn, Helmut Ziereis, and Klaus Pfeilsticker
Atmos. Meas. Tech., 10, 4209–4234, https://doi.org/10.5194/amt-10-4209-2017, https://doi.org/10.5194/amt-10-4209-2017, 2017
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This paper describes a novel instrument for the aircraft-borne remote sensing of trace gases and liquid and solid water. Until recently, such measurements could only be evaluated under clear-sky conditions. We present a characterization and error assessment of the novel "scaling method", which allows for the retrieval of absolute trace gas concentrations under all sky conditions, significantly expanding the applicability of such measurements to study atmospheric photochemistry.
David E. Oram, Matthew J. Ashfold, Johannes C. Laube, Lauren J. Gooch, Stephen Humphrey, William T. Sturges, Emma C. Leedham Elvidge, Grant L. Forster, Neil R. P. Harris, Mohammed Iqbal Mead, Azizan Abu Samah, Siew Moi Phang, Chang-Feng Ou-Yang, Neng-Huei Lin, Jia-Lin Wang, Angela K. Baker, Carl A. M. Brenninkmeijer, and David Sherry
Atmos. Chem. Phys., 17, 11929–11941, https://doi.org/10.5194/acp-17-11929-2017, https://doi.org/10.5194/acp-17-11929-2017, 2017
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We have observed large amounts of man-made chlorine compounds in E and SE Asia and in the upper tropical troposphere. These relatively short-lived compounds are not controlled by the Montreal Protocol, but if significant quantities were able to reach the stratosphere, the long-term recovery of stratospheric ozone would be delayed. We have also identified an important atmospheric transport mechanism that can rapidly transport these chemicals from E Asia to the upper troposphere via the tropics.
Bengt G. Martinsson, Johan Friberg, Oscar S. Sandvik, Markus Hermann, Peter F. J. van Velthoven, and Andreas Zahn
Atmos. Chem. Phys., 17, 10937–10953, https://doi.org/10.5194/acp-17-10937-2017, https://doi.org/10.5194/acp-17-10937-2017, 2017
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We find that the aerosol of the lowermost stratosphere has a considerable climate forcing. The upper tropospheric (UT) particulate sulfur is strongly influenced by stratospheric sources the first half of the year, whereas tropospheric sources dominate in fall; 50 % of the UT particulate sulfur (S) was found to be stratospheric at background condition, and 70 % under moderate influence from volcanism. The Asian monsoon is found to be an important tropospheric source of S in the NH extratropical UT.
Sergey Gromov, Carl A. M. Brenninkmeijer, and Patrick Jöckel
Atmos. Chem. Phys., 17, 8525–8552, https://doi.org/10.5194/acp-17-8525-2017, https://doi.org/10.5194/acp-17-8525-2017, 2017
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We revisit the proxies/uncertainties for the 13C/12C ratios of emissions of reactive C into the atmosphere. Our main findings are (i) a factor of 2 less uncertain estimate of tropospheric CO surface sources δ13C, (ii) a confirmed disagreement between the bottom-up and top-down 13CO-inclusive emission estimates, and (iii) a novel estimate of the δ13C signatures of a range of NMHCs/VOCs to be used in modelling studies. Results are based on the EMAC model emission set-up evaluated for 2000.
Johannes Bieser, Franz Slemr, Jesse Ambrose, Carl Brenninkmeijer, Steve Brooks, Ashu Dastoor, Francesco DeSimone, Ralf Ebinghaus, Christian N. Gencarelli, Beate Geyer, Lynne E. Gratz, Ian M. Hedgecock, Daniel Jaffe, Paul Kelley, Che-Jen Lin, Lyatt Jaegle, Volker Matthias, Andrei Ryjkov, Noelle E. Selin, Shaojie Song, Oleg Travnikov, Andreas Weigelt, Winston Luke, Xinrong Ren, Andreas Zahn, Xin Yang, Yun Zhu, and Nicola Pirrone
Atmos. Chem. Phys., 17, 6925–6955, https://doi.org/10.5194/acp-17-6925-2017, https://doi.org/10.5194/acp-17-6925-2017, 2017
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We conducted a multi model study to investigate our ability to reproduce the vertical distribution of mercury in the atmosphere. For this, we used observational data from over 40 aircraft flights in EU and US. We compared observations to the results of seven chemistry transport models and found that the models are able to reproduce vertical gradients of total and elemental Hg. Finally, we found that different chemical reactions seem responsible for the oxidation of Hg depending on altitude.
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.
Liang Feng, Paul I. Palmer, Hartmut Bösch, Robert J. Parker, Alex J. Webb, Caio S. C. Correia, Nicholas M. Deutscher, Lucas G. Domingues, Dietrich G. Feist, Luciana V. Gatti, Emanuel Gloor, Frank Hase, Rigel Kivi, Yi Liu, John B. Miller, Isamu Morino, Ralf Sussmann, Kimberly Strong, Osamu Uchino, Jing Wang, and Andreas Zahn
Atmos. Chem. Phys., 17, 4781–4797, https://doi.org/10.5194/acp-17-4781-2017, https://doi.org/10.5194/acp-17-4781-2017, 2017
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We use the GEOS-Chem global 3-D model of atmospheric chemistry and transport and an ensemble Kalman filter to simultaneously infer regional fluxes of methane (CH4) and carbon dioxide (CO2) directly from GOSAT retrievals of XCH4:XCO2, using sparse ground-based CH4 and CO2 mole fraction data to anchor the ratio. Our results show that assimilation of GOSAT data significantly reduced the posterior uncertainty and changed the a priori spatial distribution of CH4 emissions.
Johannes Eckstein, Roland Ruhnke, Andreas Zahn, Marco Neumaier, Ole Kirner, and Peter Braesicke
Atmos. Chem. Phys., 17, 2775–2794, https://doi.org/10.5194/acp-17-2775-2017, https://doi.org/10.5194/acp-17-2775-2017, 2017
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Data on atmospheric trace gases have been collected with instruments on-board a commercial airliner for more than 10 years in the CARIBIC project. We investigate which species in the dataset can be used for a representative climatology, by comparing data from the chemistry–climate model EMAC along the flight paths to a larger set of model data. We find that long-lived species are captured quite well by the CARIBIC sample while this is not the case for more variable, shorter-lived species.
Garlich Fischbeck, Harald Bönisch, Marco Neumaier, Carl A. M. Brenninkmeijer, Johannes Orphal, Joel Brito, Julia Becker, Detlev Sprung, Peter F. J. van Velthoven, and Andreas Zahn
Atmos. Chem. Phys., 17, 1985–2008, https://doi.org/10.5194/acp-17-1985-2017, https://doi.org/10.5194/acp-17-1985-2017, 2017
Bärbel Vogel, Gebhard Günther, Rolf Müller, Jens-Uwe Grooß, Armin Afchine, Heiko Bozem, Peter Hoor, Martina Krämer, Stefan Müller, Martin Riese, Christian Rolf, Nicole Spelten, Gabriele P. Stiller, Jörn Ungermann, and Andreas Zahn
Atmos. Chem. Phys., 16, 15301–15325, https://doi.org/10.5194/acp-16-15301-2016, https://doi.org/10.5194/acp-16-15301-2016, 2016
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The identification of transport pathways from the Asian monsoon anticyclone into the lower stratosphere is unclear. Global simulations with the CLaMS model demonstrate that source regions in Asia and in the Pacific Ocean have a significant impact on the chemical composition of the lower stratosphere of the Northern Hemisphere by flooding the extratropical lower stratosphere with young moist air masses. Two main horizontal transport pathways from the Asian monsoon anticyclone are identified.
Johannes C. Laube, Norfazrin Mohd Hanif, Patricia Martinerie, Eileen Gallacher, Paul J. Fraser, Ray Langenfelds, Carl A. M. Brenninkmeijer, Jakob Schwander, Emmanuel Witrant, Jia-Lin Wang, Chang-Feng Ou-Yang, Lauren J. Gooch, Claire E. Reeves, William T. Sturges, and David E. Oram
Atmos. Chem. Phys., 16, 15347–15358, https://doi.org/10.5194/acp-16-15347-2016, https://doi.org/10.5194/acp-16-15347-2016, 2016
Andreas Weigelt, Franz Slemr, Ralf Ebinghaus, Nicola Pirrone, Johannes Bieser, Jan Bödewadt, Giulio Esposito, and Peter F. J. van Velthoven
Atmos. Chem. Phys., 16, 13653–13668, https://doi.org/10.5194/acp-16-13653-2016, https://doi.org/10.5194/acp-16-13653-2016, 2016
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Hg ∕ SO2, Hg ∕ CO, and NOx ∕ SO2 emission ratios (ERs) in the plume of the coal-fired power plant (CFPP), Lippendorf, near Leipzig in Germany, were determined in August 2013. GOM fraction of mercury emissions was also assessed. Measured Hg ∕ SO2 and Hg ∕ CO ERs were consistent with the ratios calculated from annual emissions in 2013 reported by the CFPP operator. The NOx ∕ SO2 ER was somewhat lower. GOM fractions of ~ 40 % of CFPP mercury emissions in current emission inventories are overestimated.
Cathy M. Trudinger, Paul J. Fraser, David M. Etheridge, William T. Sturges, Martin K. Vollmer, Matt Rigby, Patricia Martinerie, Jens Mühle, David R. Worton, Paul B. Krummel, L. Paul Steele, Benjamin R. Miller, Johannes Laube, Francis S. Mani, Peter J. Rayner, Christina M. Harth, Emmanuel Witrant, Thomas Blunier, Jakob Schwander, Simon O'Doherty, and Mark Battle
Atmos. Chem. Phys., 16, 11733–11754, https://doi.org/10.5194/acp-16-11733-2016, https://doi.org/10.5194/acp-16-11733-2016, 2016
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Perfluorocarbons (PFCs) are potent, long-lived and mostly man-made greenhouse gases released to the atmosphere mainly during aluminium production and semiconductor manufacture. Here we present the first continuous histories of three PFCs from 1800 to 2014, derived from measurements of these PFCs in the atmosphere and in air bubbles in polar ice. The records show how human actions have affected these important greenhouse gases over the past century.
Graham P. Mills, Glyn D. Hiatt-Gipson, Sean P. Bew, and Claire E. Reeves
Atmos. Meas. Tech., 9, 4533–4545, https://doi.org/10.5194/amt-9-4533-2016, https://doi.org/10.5194/amt-9-4533-2016, 2016
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The paper describes the development of an instrument to measure isoprene-derived nitrates in the atmosphere, compounds that are crucial to understanding the impact of biogenic hydrocarbons on ozone production. The instrument is suitable for deployment in field studies.
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
Franz Slemr, Andreas Weigelt, Ralf Ebinghaus, Hans H. Kock, Jan Bödewadt, Carl A. M. Brenninkmeijer, Armin Rauthe-Schöch, Stefan Weber, Markus Hermann, Julia Becker, Andreas Zahn, and Bengt Martinsson
Atmos. Meas. Tech., 9, 2291–2302, https://doi.org/10.5194/amt-9-2291-2016, https://doi.org/10.5194/amt-9-2291-2016, 2016
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The goal of CARIBIC (Civil Aircraft for the Regular Investigation of the atmosphere Based on an Instrumented Container) is to carry out regular and detailed observations of atmospheric chemistry at 9–12 km altitude. Mercury has been measured since May 2005 during intercontinental flights between Europe and South and North America, Africa, and Asia. Here we describe the instrument modifications, the post-flight processing of the raw instrument signal, and the fractionation experiments.
Markus Hermann, Andreas Weigelt, Denise Assmann, Sascha Pfeifer, Thomas Müller, Thomas Conrath, Jens Voigtländer, Jost Heintzenberg, Alfred Wiedensohler, Bengt G. Martinsson, Terry Deshler, Carl A. M. Brenninkmeijer, and Andreas Zahn
Atmos. Meas. Tech., 9, 2179–2194, https://doi.org/10.5194/amt-9-2179-2016, https://doi.org/10.5194/amt-9-2179-2016, 2016
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Aerosol particles are an important component of the Earth's atmosphere. Here we describe the composition and characterization of a new optical particle size spectrometer (OPSS) for aircraft-borne measurements of the aerosol particle size distribution (how many particles there are with a certain size) in the 140–1050 nm size range. The OPSS was characterized throughout concerning its measurement capabilities (response, pressure dependence, coincidence) and validated versus balloon measurement.
Patrick Jöckel, Holger Tost, Andrea Pozzer, Markus Kunze, Oliver Kirner, Carl A. M. Brenninkmeijer, Sabine Brinkop, Duy S. Cai, Christoph Dyroff, Johannes Eckstein, Franziska Frank, Hella Garny, Klaus-Dirk Gottschaldt, Phoebe Graf, Volker Grewe, Astrid Kerkweg, Bastian Kern, Sigrun Matthes, Mariano Mertens, Stefanie Meul, Marco Neumaier, Matthias Nützel, Sophie Oberländer-Hayn, Roland Ruhnke, Theresa Runde, Rolf Sander, Dieter Scharffe, and Andreas Zahn
Geosci. Model Dev., 9, 1153–1200, https://doi.org/10.5194/gmd-9-1153-2016, https://doi.org/10.5194/gmd-9-1153-2016, 2016
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With an advanced numerical global chemistry climate model (CCM) we performed several detailed
combined hind-cast and projection simulations of the period 1950 to 2100 to assess the
past, present, and potential future dynamical and chemical state of the Earth atmosphere.
The manuscript documents the model and the various applied model set-ups and provides
a first evaluation of the simulation results from a global perspective as a quality check of the data.
Andreas Weigelt, Ralf Ebinghaus, Nicola Pirrone, Johannes Bieser, Jan Bödewadt, Giulio Esposito, Franz Slemr, Peter F. J. van Velthoven, Andreas Zahn, and Helmut Ziereis
Atmos. Chem. Phys., 16, 4135–4146, https://doi.org/10.5194/acp-16-4135-2016, https://doi.org/10.5194/acp-16-4135-2016, 2016
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We show the first mercury profile measurements over Europe since 1996. Besides gaseous elemental mercury (GEM) and total gaseous mercury (TGM), the gases CO, SO2, NOx, and O3 were measured from aboard a research aircraft over four European locations. Compared to the boundary layer, the concentration of GEM and TGM in the free troposphere was 10–30% lower. Inside the individual layers no vertical gradient was apparent. Combined with CARIBIC data, a unique profile from 0.4 to 10.5 km is provided.
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.
Narendra Ojha, Andrea Pozzer, Armin Rauthe-Schöch, Angela K. Baker, Jongmin Yoon, Carl A. M. Brenninkmeijer, and Jos Lelieveld
Atmos. Chem. Phys., 16, 3013–3032, https://doi.org/10.5194/acp-16-3013-2016, https://doi.org/10.5194/acp-16-3013-2016, 2016
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We compare simulations of ozone and carbon monoxide using a regional chemistry transport model (WRF-Chem) with aircraft observations from CARIBIC program over India during monsoon period. Sensitivity simulations are conducted to assess the influences of regional emissions and long-range transport.
X. Lin, N. K. Indira, M. Ramonet, M. Delmotte, P. Ciais, B. C. Bhatt, M. V. Reddy, D. Angchuk, S. Balakrishnan, S. Jorphail, T. Dorjai, T. T. Mahey, S. Patnaik, M. Begum, C. Brenninkmeijer, S. Durairaj, R. Kirubagaran, M. Schmidt, P. S. Swathi, N. V. Vinithkumar, C. Yver Kwok, and V. K. Gaur
Atmos. Chem. Phys., 15, 9819–9849, https://doi.org/10.5194/acp-15-9819-2015, https://doi.org/10.5194/acp-15-9819-2015, 2015
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We present 5-year flask measurements (2007–2011) of greenhouse gases (GHGs) at three atmospheric stations in India. The results suggest significant sources of CO2, CH4, N2O, CO, and H2 over S and NE India, while SF6 sources are weak. The seasonal cycles for each species reflect the seasonality of sources/sinks and influences of the Indian monsoon circulations. The data show potential to infer regional patterns of GHG fluxes and atmospheric transport over this under-documented region.
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
S. J. Allin, J. C. Laube, E. Witrant, J. Kaiser, E. McKenna, P. Dennis, R. Mulvaney, E. Capron, P. Martinerie, T. Röckmann, T. Blunier, J. Schwander, P. J. Fraser, R. L. Langenfelds, and W. T. Sturges
Atmos. Chem. Phys., 15, 6867–6877, https://doi.org/10.5194/acp-15-6867-2015, https://doi.org/10.5194/acp-15-6867-2015, 2015
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Stratospheric ozone protects life on Earth from harmful UV-B radiation. Chlorofluorocarbons (CFCs) are man-made compounds which act to destroy this barrier.
This paper presents (1) the first measurements of the stratospheric δ(37Cl) of CFCs -11 and -113; (2) the first quantification of long-term trends in the tropospheric δ(37Cl) of CFCs -11, -12 and -113.
This study provides a better understanding of source and sink processes associated with these destructive compounds.
J. Ungermann, J. Blank, M. Dick, A. Ebersoldt, F. Friedl-Vallon, A. Giez, T. Guggenmoser, M. Höpfner, T. Jurkat, M. Kaufmann, S. Kaufmann, A. Kleinert, M. Krämer, T. Latzko, H. Oelhaf, F. Olchewski, P. Preusse, C. Rolf, J. Schillings, O. Suminska-Ebersoldt, V. Tan, N. Thomas, C. Voigt, A. Zahn, M. Zöger, and M. Riese
Atmos. Meas. Tech., 8, 2473–2489, https://doi.org/10.5194/amt-8-2473-2015, https://doi.org/10.5194/amt-8-2473-2015, 2015
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The GLORIA sounder is an airborne infrared limb-imager combining a two-dimensional infrared detector with a Fourier transform spectrometer. It was operated aboard the new German Gulfstream G550 research aircraft HALO during the TACTS and ESMVAL campaigns in summer 2012. This paper describes the retrieval of temperature, as well as H2O, HNO3, and O3 cross sections from GLORIA dynamics mode spectra. A high correlation is achieved between the remote sensing and the in situ trace gas measurements.
C. Dyroff, S. Sanati, E. Christner, A. Zahn, M. Balzer, H. Bouquet, J. B. McManus, Y. González-Ramos, and M. Schneider
Atmos. Meas. Tech., 8, 2037–2049, https://doi.org/10.5194/amt-8-2037-2015, https://doi.org/10.5194/amt-8-2037-2015, 2015
Emma C. Leedham Elvidge, D. E. Oram, J. C. Laube, A. K. Baker, S. A. Montzka, S. Humphrey, D. A. O'Sullivan, and C. A. M. Brenninkmeijer
Atmos. Chem. Phys., 15, 1939–1958, https://doi.org/10.5194/acp-15-1939-2015, https://doi.org/10.5194/acp-15-1939-2015, 2015
S. Gromov and C. A. M. Brenninkmeijer
Atmos. Chem. Phys., 15, 1901–1912, https://doi.org/10.5194/acp-15-1901-2015, https://doi.org/10.5194/acp-15-1901-2015, 2015
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We present observational data on δ18O(O3) from the UT/LMS, the region to date not covered by the ozone isotope composition measurements. It is to bridge the gap between the tropospheric (mostly surface) and stratospheric measurement data.
We demonstrate an approach suitable for isotope mass-balance calculations (“Keeling plot”) in intricate cases, i.e. admixing of the (unknown) source in question to the reservoirs with (unknown) variable starting compositions.
J. W. Taylor, J. D. Allan, G. Allen, H. Coe, P. I. Williams, M. J. Flynn, M. Le Breton, J. B. A. Muller, C. J. Percival, D. Oram, G. Forster, J. D. Lee, A. R. Rickard, M. Parrington, and P. I. Palmer
Atmos. Chem. Phys., 14, 13755–13771, https://doi.org/10.5194/acp-14-13755-2014, https://doi.org/10.5194/acp-14-13755-2014, 2014
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We present a case study of BC wet removal by examining aerosol properties in three biomass burning plumes, one of which passed through a precipitating cloud. Nucleation scavenging preferentially removed the largest and most coated BC-containing particles. Calculated single-scattering albedo (SSA) showed little variation, as a large number of non-BC particles were also present in the precipitation-affected plume.
B. Vogel, G. Günther, R. Müller, J.-U. Grooß, P. Hoor, M. Krämer, S. Müller, A. Zahn, and M. Riese
Atmos. Chem. Phys., 14, 12745–12762, https://doi.org/10.5194/acp-14-12745-2014, https://doi.org/10.5194/acp-14-12745-2014, 2014
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Enhanced tropospheric trace gases (e.g. pollutants) were measured in situ in
the lowermost stratosphere over Northern Europe on 26 September 2012
during the TACTS aircraft campaign. We found that the combination of rapid uplift by a typhoon and eastward eddy shedding from the Asian monsoon anticyclone is a novel fast transport pathway
that may carry boundary emissions from Southeast
Asia/western Pacific within approximately 5 weeks to the lowermost
stratosphere in Northern Europe.
J. D. Allan, W. T. Morgan, E. Darbyshire, M. J. Flynn, P. I. Williams, D. E. Oram, P. Artaxo, J. Brito, J. D. Lee, and H. Coe
Atmos. Chem. Phys., 14, 11393–11407, https://doi.org/10.5194/acp-14-11393-2014, https://doi.org/10.5194/acp-14-11393-2014, 2014
T. P. C. van Noije, P. Le Sager, A. J. Segers, P. F. J. van Velthoven, M. C. Krol, W. Hazeleger, A. G. Williams, and S. D. Chambers
Geosci. Model Dev., 7, 2435–2475, https://doi.org/10.5194/gmd-7-2435-2014, https://doi.org/10.5194/gmd-7-2435-2014, 2014
C. Warneke, F. Geiger, P. M. Edwards, W. Dube, G. Pétron, J. Kofler, A. Zahn, S. S. Brown, M. Graus, J. B. Gilman, B. M. Lerner, J. Peischl, T. B. Ryerson, J. A. de Gouw, and J. M. Roberts
Atmos. Chem. Phys., 14, 10977–10988, https://doi.org/10.5194/acp-14-10977-2014, https://doi.org/10.5194/acp-14-10977-2014, 2014
B. G. Martinsson, J. Friberg, S. M. Andersson, A. Weigelt, M. Hermann, D. Assmann, J. Voigtländer, C. A. M. Brenninkmeijer, P. J. F. van Velthoven, and A. Zahn
Atmos. Meas. Tech., 7, 2581–2596, https://doi.org/10.5194/amt-7-2581-2014, https://doi.org/10.5194/amt-7-2581-2014, 2014
M. S. Mohd Nadzir, S. M. Phang, M. R. Abas, N. Abdul Rahman, A. Abu Samah, W. T. Sturges, D. E. Oram, G. P. Mills, Emma C. Leedham Elvidge, J. A. Pyle, N. R. P. Harris, A. D. Robinson, M. J. Ashfold, M. I. Mead, M. T. Latif, M. F. Khan, A. M. Amiruddin, N. Banan, and M. M. Hanafiah
Atmos. Chem. Phys., 14, 8137–8148, https://doi.org/10.5194/acp-14-8137-2014, https://doi.org/10.5194/acp-14-8137-2014, 2014
S. Sala, H. Bönisch, T. Keber, D. E. Oram, G. Mills, and A. Engel
Atmos. Chem. Phys., 14, 6903–6923, https://doi.org/10.5194/acp-14-6903-2014, https://doi.org/10.5194/acp-14-6903-2014, 2014
K.-P. Heue, H. Riede, D. Walter, C. A. M. Brenninkmeijer, T. Wagner, U. Frieß, U. Platt, A. Zahn, G. Stratmann, and H. Ziereis
Atmos. Chem. Phys., 14, 6621–6642, https://doi.org/10.5194/acp-14-6621-2014, https://doi.org/10.5194/acp-14-6621-2014, 2014
C. Dyroff, A. Zahn, S. Sanati, E. Christner, A. Rauthe-Schöch, and T. J. Schuck
Atmos. Meas. Tech., 7, 743–755, https://doi.org/10.5194/amt-7-743-2014, https://doi.org/10.5194/amt-7-743-2014, 2014
J. E. Williams, G. Le Bras, A. Kukui, H. Ziereis, and C. A. M. Brenninkmeijer
Atmos. Chem. Phys., 14, 2363–2382, https://doi.org/10.5194/acp-14-2363-2014, https://doi.org/10.5194/acp-14-2363-2014, 2014
D. Stone, M. J. Evans, H. Walker, T. Ingham, S. Vaughan, B. Ouyang, O. J. Kennedy, M. W. McLeod, R. L. Jones, J. Hopkins, S. Punjabi, R. Lidster, J. F. Hamilton, J. D. Lee, A. C. Lewis, L. J. Carpenter, G. Forster, D. E. Oram, C. E. Reeves, S. Bauguitte, W. Morgan, H. Coe, E. Aruffo, C. Dari-Salisburgo, F. Giammaria, P. Di Carlo, and D. E. Heard
Atmos. Chem. Phys., 14, 1299–1321, https://doi.org/10.5194/acp-14-1299-2014, https://doi.org/10.5194/acp-14-1299-2014, 2014
R. Hossaini, H. Mantle, M. P. Chipperfield, S. A. Montzka, P. Hamer, F. Ziska, B. Quack, K. Krüger, S. Tegtmeier, E. Atlas, S. Sala, A. Engel, H. Bönisch, T. Keber, D. Oram, G. Mills, C. Ordóñez, A. Saiz-Lopez, N. Warwick, Q. Liang, W. Feng, F. Moore, B. R. Miller, V. Marécal, N. A. D. Richards, M. Dorf, and K. Pfeilsticker
Atmos. Chem. Phys., 13, 11819–11838, https://doi.org/10.5194/acp-13-11819-2013, https://doi.org/10.5194/acp-13-11819-2013, 2013
E. V. Berezina, N. F. Elansky, K. B. Moiseenko, I. B. Belikov, R. A. Shumsky, A. N. Safronov, and C. A. M Brenninkmeijer
Atmos. Chem. Phys., 13, 11695–11708, https://doi.org/10.5194/acp-13-11695-2013, https://doi.org/10.5194/acp-13-11695-2013, 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
M. Parrington, P. I. Palmer, A. C. Lewis, J. D. Lee, A. R. Rickard, P. Di Carlo, J. W. Taylor, J. R. Hopkins, S. Punjabi, D. E. Oram, G. Forster, E. Aruffo, S. J. Moller, S. J.-B. Bauguitte, J. D. Allan, H. Coe, and R. J. Leigh
Atmos. Chem. Phys., 13, 7321–7341, https://doi.org/10.5194/acp-13-7321-2013, https://doi.org/10.5194/acp-13-7321-2013, 2013
P. I. Palmer, M. Parrington, J. D. Lee, A. C. Lewis, A. R. Rickard, P. F. Bernath, T. J. Duck, D. L. Waugh, D. W. Tarasick, S. Andrews, E. Aruffo, L. J. Bailey, E. Barrett, S. J.-B. Bauguitte, K. R. Curry, P. Di Carlo, L. Chisholm, L. Dan, G. Forster, J. E. Franklin, M. D. Gibson, D. Griffin, D. Helmig, J. R. Hopkins, J. T. Hopper, M. E. Jenkin, D. Kindred, J. Kliever, M. Le Breton, S. Matthiesen, M. Maurice, S. Moller, D. P. Moore, D. E. Oram, S. J. O'Shea, R. C. Owen, C. M. L. S. Pagniello, S. Pawson, C. J. Percival, J. R. Pierce, S. Punjabi, R. M. Purvis, J. J. Remedios, K. M. Rotermund, K. M. Sakamoto, A. M. da Silva, K. B. Strawbridge, K. Strong, J. Taylor, R. Trigwell, K. A. Tereszchuk, K. A. Walker, D. Weaver, C. Whaley, and J. C. Young
Atmos. Chem. Phys., 13, 6239–6261, https://doi.org/10.5194/acp-13-6239-2013, https://doi.org/10.5194/acp-13-6239-2013, 2013
J. E. Williams, P. F. J. van Velthoven, and C. A. M. Brenninkmeijer
Atmos. Chem. Phys., 13, 2857–2891, https://doi.org/10.5194/acp-13-2857-2013, https://doi.org/10.5194/acp-13-2857-2013, 2013
J. C. Laube, A. Keil, H. Bönisch, A. Engel, T. Röckmann, C. M. Volk, and W. T. Sturges
Atmos. Chem. Phys., 13, 2779–2791, https://doi.org/10.5194/acp-13-2779-2013, https://doi.org/10.5194/acp-13-2779-2013, 2013
S. M. Andersson, B. G. Martinsson, J. Friberg, C. A. M. Brenninkmeijer, A. Rauthe-Schöch, M. Hermann, P. F. J. van Velthoven, and A. Zahn
Atmos. Chem. Phys., 13, 1781–1796, https://doi.org/10.5194/acp-13-1781-2013, https://doi.org/10.5194/acp-13-1781-2013, 2013
Ø. Hodnebrog, T. K. Berntsen, O. Dessens, M. Gauss, V. Grewe, I. S. A. Isaksen, B. Koffi, G. Myhre, D. Olivié, M. J. Prather, F. Stordal, S. Szopa, Q. Tang, P. van Velthoven, and J. E. Williams
Atmos. Chem. Phys., 12, 12211–12225, https://doi.org/10.5194/acp-12-12211-2012, https://doi.org/10.5194/acp-12-12211-2012, 2012
Related subject area
Subject: Gases | Research Activity: Field Measurements | Altitude Range: Troposphere | Science Focus: Chemistry (chemical composition and reactions)
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
Measurement report: Sources, sinks, and lifetime of NOx in a suburban temperate forest at night
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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
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Observations of the vertical distributions of summertime atmospheric pollutants in Nam Co: OH production and source analysis
Measurement report: Elevated atmospheric ammonia may promote particle pH and HONO formation – insights from the COVID-19 pandemic
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The role of oceanic ventilation and terrestrial outflow in atmospheric non-methane hydrocarbons over the Chinese marginal seas
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Seasonal Air Concentration Variability, Gas/Particle Partitioning, Precipitation Scavenging, and Air-Water Equilibrium of Organophosphate Esters in Southern Canada
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Cloud processing of DMS oxidation products limits SO2 and OCS production in the Eastern North Atlantic marine boundary layer
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Measurement report: Enhanced photochemical formation of formic and isocyanic acids in urban regions aloft – insights from tower-based online gradient measurements
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Surface snow bromide and nitrate at Eureka, Canada, in early spring and implications for polar boundary layer chemistry
Molecular and seasonal characteristics of organic vapors in urban Beijing: insights from Vocus-PTR measurements
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Analysis of ozone vertical profile day-to-day variability in the lower troposphere during the Paris-2022 ACROSS campaign
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Intensive photochemical oxidation in the marine atmosphere: evidence from direct radical measurements
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.
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.
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.
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
EGUsphere, https://doi.org/10.5194/egusphere-2024-1883, https://doi.org/10.5194/egusphere-2024-1883, 2024
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Organophosphate esters are important man-made trace contaminants. Measuring them in the atmospheric gas phase, particles, precipitation and surface water from Canada, we explore seasonal concentration variability, gas/particle partitioning, precipitation scavenging, and air-water equilibrium. Whereas higher concentrations in summer 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
EGUsphere, https://doi.org/10.5194/egusphere-2024-2127, https://doi.org/10.5194/egusphere-2024-2127, 2024
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Comprehensive observations of HONO and NOx fluxes were first performed over paddy fields in the Huaihe River Basin. The consecutive peaks in HONO flux and NO flux demonstrated a potentially enhanced release of HONO and NO due to soil tillage, whereas higher WFPS (~80 %) inhibited microbial processes following irrigation. Notably, the biological processes and light-driven NO2 reactions on the surface could both be sources of HONO and influence the local HONO budget during rotary tillage.
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.
Junwei Song, Georgios I. Gkatzelis, Ralf Tillmann, Nicolas Brüggemann, Thomas Leisner, and Harald Saathoff
EGUsphere, https://doi.org/10.5194/egusphere-2024-1768, https://doi.org/10.5194/egusphere-2024-1768, 2024
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VOCs and organic aerosol (OA) particles were measured online at an European stressed pine forest site. Higher temperatures can enhance the forest emissions of biogenic VOCs exceeding their photochemical consumption during daytime. Weakly oxidized monoterpene products dominated the VOCs during nighttime. Moreover, increasing relative humidity can promote the gas-to-particle partitioning of these weakly oxidized monoterpene products, leading to increased OA mass.
Jakob Boyd Pernov, Jens Liengaard Hjorth, Lise Lotte Sørensen, and Henrik Skov
EGUsphere, https://doi.org/10.5194/egusphere-2024-1676, https://doi.org/10.5194/egusphere-2024-1676, 2024
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Arctic ozone depletion events (ODEs) occurs 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.
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.
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.
Zhaojin An, Rujing Yin, Xinyan Zhao, Xiaoxiao Li, Yi Yuan, Junchen Guo, Yuyang Li, Xue Li, Dandan Li, Yaowei Li, Dongbin Wang, Chao Yan, Kebin He, Douglas R. Worsnop, Frank N. Keutsch, and Jingkun Jiang
EGUsphere, https://doi.org/10.5194/egusphere-2024-1325, https://doi.org/10.5194/egusphere-2024-1325, 2024
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Online Vocus-PTR measurements show the compositions and seasonal variations of organic vapors in urban Beijing. With enhanced sensitivity and mass resolution, various sub-ppt level species and organics with multiple oxygens (≥3) were discovered. 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 of them could be influenced by primary emissions.
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.
Gerard Ancellet, Camille Viatte, Anne Boynard, François Ravetta, Jacques Pelon, Cristelle Cailteau-Fischbach, Pascal Genau, Julie Capo, Axel Roy, and Philippe Nédélec
EGUsphere, https://doi.org/10.5194/egusphere-2024-892, https://doi.org/10.5194/egusphere-2024-892, 2024
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Characterization of ozone pollution in urban areas has benefited from a measurement campaign in summer 2022 in the Paris region. The analysis is based on 21 days of lidar and aircraft observations. The main objective is a sensitivity analysis of ozone pollution to first the micrometeorological processes in the urban atmospheric boundary layer, and second, the transport of regional pollution. The paper also discuss to what extent satellite observations can track the observed ozone plumes.
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.
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
EGUsphere, https://doi.org/10.5194/egusphere-2024-284, https://doi.org/10.5194/egusphere-2024-284, 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 under-sampled. 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 at Zoétélé (Cameroon) and Skukuza (South Africa).
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.
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.
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.
Bowen Zhang, Dong Zhang, Zhe Dong, Xinshuai Song, Ruiqin Zhang, and Xiao Li
EGUsphere, https://doi.org/10.5194/egusphere-2024-575, https://doi.org/10.5194/egusphere-2024-575, 2024
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Continuous online VOCs monitoring was carried out at an urban site in a traffic-hub city for two months during the Omicron-infected stage. The characteristics and variations of VOCs in different periods were studied, and their impact on the formation of SOA were evaluated. The work in this manuscript evaluated the influence of the policy variation on VOCs pollution, which will provide some basis for VOCs pollution research and control of pollution sources.
Sachin Mishra, Vinayak Sinha, Haseeb Hakkim, Arpit Awasthi, Sachin D. Ghude, Vijay Kumar Soni, Narendra Nigam, Baerbel Sinha, and Madhavan N. Rajeevan
EGUsphere, https://doi.org/10.5194/egusphere-2024-500, https://doi.org/10.5194/egusphere-2024-500, 2024
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We quantified 111 gases using extended volatility mass spectrometry to understand how changes in seasonality and emissions lead from clean air in monsoon to extremely polluted air in the post-monsoon season in Delhi. Averaged total mass concentrations (260 µgm-3) were >4 times in polluted periods, driven by biomass burning emissions and reduced atmospheric ventilation. Reactive gaseous nitrogen, chlorine and sulphur compounds hitherto un-reported from such a polluted environment were discovered.
Yao Yan Huang and D. James Donaldson
Atmos. Chem. Phys., 24, 2387–2398, https://doi.org/10.5194/acp-24-2387-2024, https://doi.org/10.5194/acp-24-2387-2024, 2024
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Ground-level ozone interacts at the lake–land boundary; this is important to our understanding and modelling of atmospheric chemistry and air pollution in the lower atmosphere. We show that a steep ozone gradient occurs year-round moving inland up to 1 km from the lake and that this gradient is influenced by seasonal factors on the local land environment, where more rural areas are more greatly affected seasonally.
Katrin Müller, Jordis S. Tradowsky, Peter von der Gathen, Christoph Ritter, Sharon Patris, Justus Notholt, and Markus Rex
Atmos. Chem. Phys., 24, 2169–2193, https://doi.org/10.5194/acp-24-2169-2024, https://doi.org/10.5194/acp-24-2169-2024, 2024
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The Palau Atmospheric Observatory is introduced as an ideal site to detect changes in atmospheric composition and dynamics above the remote tropical western Pacific. We focus on the ozone sounding program from 2016–2021, including El Niño 2016. The year-round high convective activity is reflected in dominant low tropospheric ozone and high relative humidity. Their seasonal distributions are unique compared to other tropical sites and are modulated by the Intertropical Convergence Zone.
Ziyan Guo, Keding Lu, Pengxiang Qiu, Mingyi Xu, and Zhaobing Guo
Atmos. Chem. Phys., 24, 2195–2205, https://doi.org/10.5194/acp-24-2195-2024, https://doi.org/10.5194/acp-24-2195-2024, 2024
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The formation of secondary sulfate needs to be further explored. In this work, we simultaneously measured sulfur and oxygen isotopic compositions to gain an increased understanding of specific sulfate formation processes. The results indicated that secondary sulfate was mainly ascribed to SO2 homogeneous oxidation by OH radicals and heterogeneous oxidation by H2O2 and Fe3+ / O2. This study is favourable for deeply investigating the sulfur cycle in the atmosphere.
Imran A. Girach, Narendra Ojha, Prabha R. Nair, Kandula V. Subrahmanyam, Neelakantan Koushik, Mohammed M. Nazeer, Nadimpally Kiran Kumar, Surendran Nair Suresh Babu, Jos Lelieveld, and Andrea Pozzer
Atmos. Chem. Phys., 24, 1979–1995, https://doi.org/10.5194/acp-24-1979-2024, https://doi.org/10.5194/acp-24-1979-2024, 2024
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We investigate surface ozone variability in East Antarctica based on measurements and EMAC global model simulations during austral summer. Nearly half of the surface ozone is found to be of stratospheric origin. The east coast of Antarctica acts as a stronger sink of ozone than surrounding regions. Photochemical loss of ozone is counterbalanced by downward transport of ozone. The study highlights the intertwined role of chemistry and dynamics in governing ozone variations over East Antarctica.
Ying Zhang, Duzitian Li, Xu-Cheng He, Wei Nie, Chenjuan Deng, Runlong Cai, Yuliang Liu, Yishuo Guo, Chong Liu, Yiran Li, Liangduo Chen, Yuanyuan Li, Chenjie Hua, Tingyu Liu, Zongcheng Wang, Jiali Xie, Lei Wang, Tuukka Petäjä, Federico Bianchi, Ximeng Qi, Xuguang Chi, Pauli Paasonen, Yongchun Liu, Chao Yan, Jingkun Jiang, Aijun Ding, and Markku Kulmala
Atmos. Chem. Phys., 24, 1873–1893, https://doi.org/10.5194/acp-24-1873-2024, https://doi.org/10.5194/acp-24-1873-2024, 2024
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This study conducts a long-term observation of gaseous iodine oxoacids in two Chinese megacities, revealing their ubiquitous presence with peak concentrations (up to 0.1 pptv) in summer. Our analysis suggests a mix of terrestrial and marine sources for iodine. Additionally, iodic acid is identified as a notable contributor to sub-3 nm particle growth and particle survival probability.
Guoxian Zhang, Renzhi Hu, Pinhua Xie, Changjin Hu, Xiaoyan Liu, Liujun Zhong, Haotian Cai, Bo Zhu, Shiyong Xia, Xiaofeng Huang, Xin Li, and Wenqing Liu
Atmos. Chem. Phys., 24, 1825–1839, https://doi.org/10.5194/acp-24-1825-2024, https://doi.org/10.5194/acp-24-1825-2024, 2024
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Comprehensive observation of HOx radicals was conducted at a coastal site in the Pearl River Delta. Radical chemistry was influenced by different air masses in a time-dependent way. Land mass promotes a more active photochemical process, with daily averages of 7.1 × 106 and 5.2 × 108 cm−3 for OH and HO2 respectively. The rapid oxidation process was accompanied by a higher diurnal HONO concentration, which influences the ozone-sensitive system and eventually magnifies the background ozone.
Cited articles
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Brinckmann, S., Engel, A., Bönisch, H., Quack, B., and Atlas, E.: Short-lived brominated hydrocarbons – observations in the source regions and the tropical tropopause layer, Atmos. Chem. Phys., 12, 1213–1228, https://doi.org/10.5194/acp-12-1213-2012, 2012.
Butler, J. H., King, D. B., Lobert, J. M., Montzka, S. A., Yvon-Lewis, S. A., Hall, B. D., Warwick, N. J., Mondeel, D. J., Aydin, M., and Elkins, J. W.: Oceanic distributions and emissions of short-lived halocarbons, Global Biogeochem. Cy., 21, 1–11, https://doi.org/10.1029/2006GB002732, 2007.
Carpenter, L. J., Wevill, D. J., O'Doherty, S., Spain, G. and Simmonds, P. G.: Atmospheric bromoform at Mace Head, Ireland: seasonality and evidence for a peatland source, Atmos. Chem. Phys., 5, 2927–2934, https://doi.org/10.5194/acp-5-2927-2005, 2005.
Carpenter, L. J., Jones, C. E., Dunk, R. M., Hornsby, K. E., and Woeltjen, J.: Air-sea fluxes of biogenic bromine from the tropical and North Atlantic Ocean, Atmos. Chem. Phys., 9, 1805–1816, https://doi.org/10.5194/acp-9-1805-2009, 2009.
Dessens, O., Zeng, G., Warwick, N., and Pyle, J.: Short-lived bromine compounds in the lower stratosphere; impact of climate change on ozone, Atmos. Sci. Lett., 10, 201–206, https://doi.org/10.1002/asl.236, 2009.
Fueglistaler, S., Dessler, A. E., Dunkerton, T. J., Folkins, I., Fu, Q. and Mote, P. W.: Tropical tropopause layer, Rev. Geophys., 47, RG1004, https://doi.org/10.1029/2008RG000267, 2009.
Gettelman, A., Hoor, P., Pan, L. L., Randel, W. J., Hegglin, M. I., and Birner, T.: The extratropical upper troposphere and lower stratosphere, Rev. Geophys., 49, 1–31, https://doi.org/10.1029/2011RG000355, 2011.
Hall, B. D., Engel, A., Mühle, J., Elkins, J. W., Artuso, F., Atlas, E., Aydin, M., Blake, D., Brunke, E.-G., Chiavarini, S., Fraser, P. J., Happell, J., Krummel, P. B., Levin, I., Loewenstein, M., Maione, M., Montzka, S. A., O'Doherty, S., Reimann, S., Rhoderick, G., Saltzman, E. S., Scheel, H. E., Steele, L. P., Vollmer, M. K., Weiss, R. F., Worthy, D., and Yokouchi, Y.: Results from the International Halocarbons in Air Comparison Experiment (IHALACE), Atmos. Meas. Tech. Discuss., 6, 8021–8069, https://doi.org/10.5194/amtd-6-8021-2013, 2013.
Hepach, H., Quack, B., Ziska, F., Fuhlbrügge, S., Atlas, E. L., Krüger, K., Peeken, I., and Wallace, D. W. R.: Drivers of diel and regional variations of halocarbon emissions from the tropical North East Atlantic, Atmos. Chem. Phys., 14, 1255–1275, https://doi.org/10.5194/acp-14-1255-2014, 2014.
Hoell, J. M., Davis, D. D., Liu, S. C., Newell, R. E., Akimoto, H., McNeal, R. J. and Bendura, R. J.: The Pacific Exploratory Mission-West Phase B: February-March, 1994, J. Geophys. Res., 102, 28223–28239, https://doi.org/10.1029/97JD02581, 1997.
Hoell, J. M., Davis, D. D., Jacob, D. J., Rodgers, M. O., Newell, R. E., Fuelberg, H. E., Mcneal, R. J., Raper, J. L. and Bendura, R. J.: Pacific Exploratory Mission in the tropical Pacific :PEM-Tropics A, August-September 1996, J. Geophys. Res., 104, 5567–5583, https://doi.org/10.1029/1998JD100074, 1999.
Hossaini, R., Chipperfield, M. P., Monge-Sanz, B. M., Richards, N. A. D., Atlas, E., and Blake, D. R.: Bromoform and dibromomethane in the tropics: a 3-D model study of chemistry and transport, Atmos. Chem. Phys., 10, 719–735, https://doi.org/10.5194/acp-10-719-2010, 2010.
Hossaini, R., Chipperfield, M. P., Dhomse, S., Ordóñez, C., Saiz-Lopez. A., Abraham, N. L., Archibald, A. T., Braesicke, P., Telford, P., Warwick, N., and Pyle, J. A.: Modelling future changes to the stratospheric source gas injection of biogenic bromocarbons, Geophys. Res. Lett., 39, L20813, https://doi.org/10.1029/2012GL053401, 2012a.
Hossaini, R., Chipperfield, M. P., Feng, W., Breider, T. J., Atlas, E., Montzka, S. A., Miller, B. R., Moore, F., and Elkins, J.: The contribution of natural and anthropogenic very short-lived species to stratospheric bromine, Atmos. Chem. Phys., 12, 371–380, https://doi.org/10.5194/acp-12-371-2012, 2012b.
Hossaini, R., Mantle, H., Chipperfield, M. P., Montzka, S. A., Hamer, P., Ziska, F., Quack, B., Krüger, K., Tegtmeier, S., Atlas, E., Sala, S., Engel, A., Bönisch, H., Keber, T., Oram, D., Mills, G., Ordóñez, C., Saiz-Lopez, A., Warwick, N., Liang, Q., Feng, W., Moore, F., Miller, B. R., Marécal, V., Richards, N. A. D., Dorf, M., and Pfeilsticker, K.: Evaluating global emission inventories of biogenic bromocarbons, Atmos. Chem. Phys., 13, 11819–11838, https://doi.org/10.5194/acp-13-11819-2013, 2013.
Kroon, M., Petropavlovskikh, I., Shetter, R., Hall, S., Ullmann, K., Veefkind, J. P., McPeters, R. D., Browell, E. V., and Levelt, P. F.: OMI total ozone column validation with Aura-AVE CAFS observations, J. Geophys. Res., 113, D15S13, https://doi.org/10.1029/2007JD008795, 2008.
Lai, S. C., Baker, A. K., Schuck, T. J., Slemr, F., Brenninkmeijer, C. A. M., van Velthoven, P., Oram, D. E., Zahn, A., and Ziereis, H.: Characterization and source regions of 51 high-CO events observed during Civil Aircraft for the Regular Investigation of the Atmosphere Based on an Instrument Container (CARIBIC) flights between south China and the Philippines, 2005–2008, J. Geophys. Res., 116, 2005–2008, https://doi.org/10.1029/2011JD016375, 2011.
Laube, J. C., Engel, A., Bönisch, H., Möbius, T., Worton, D. R., Sturges, W. T., Grunow, K., and Schmidt, U.: Contribution of very short-lived organic substances to stratospheric chlorine and bromine in the tropics – a case study, Atmos. Chem. Phys., 8, 7325–7334, https://doi.org/10.5194/acp-8-7325-2008, 2008.
Laube, J. C., Martinerie, P., Witrant, E., Blunier, T., Schwander, J., Brenninkmeijer, C. A. M., Schuck, T. J., Bolder, M., Röckmann, T., van der Veen, C., Bönisch, H., Engel, A., Mills, G. P., Newland, M. J., Oram, D. E., Reeves, C. E., and Sturges, W. T.: Accelerating growth of HFC-227ea (1,1,1,2,3,3,3-heptafluoropropane) in the atmosphere, Atmos. Chem. Phys., 10, 5903–5910, https://doi.org/10.5194/acp-10-5903-2010, 2010.
Laube, J. C., Hogan, C., Newland, M. J., Mani, F. S., Fraser, P. J., Brenninkmeijer, C. A. M., Martinerie, P., Oram, D. E., Röckmann, T., Schwander, J., Witrant, E., Mills, G. P., Reeves, C. E., and Sturges, W. T.: Distributions, long term trends and emissions of four perfluorocarbons in remote parts of the atmosphere and firn air, Atmos. Chem. Phys., 12, 4081–4090, https://doi.org/10.5194/acp-12-4081-2012, 2012.
Law, K. S. and Sturges, W. T.: Halogenated Very Short-Lived Substances, in: Sci. Assess. Ozone Deplet. 2006, Glob. Ozone Res. Monit. Proj. Rep. No. 50, February, chap. 2, 2.1–2.57, World Meteorological Organization (WMO), Geneva, Switzerland, http://www.unep.ch/Ozone/Assessment_Panels/SAP/Scientific_Assessment_2006/04-Chapter_2.pdf, 2007.
Leedham, E. C., Hughes, C., Keng, F. S. L., Phang, S.-M., Malin, G., and Sturges, W. T.: Emission of atmospherically significant halocarbons by naturally occurring and farmed tropical macroalgae, Biogeosciences, 10, 3615–3633, https://doi.org/10.5194/bg-10-3615-2013, 2013.
Montzka, S. A. and Reimann, S.: Chapter 1: Ozone-Depleting Substances (ODSs) and Related Chemicals, in: WMO (World Meteorol. Organ. Sci. Assess. Ozone Deplet. 2010 Glob. Res. Monit. Proj. – Rep. No. 52, edited by: Ennis, C. E., 52, chap. 1, World Meteorological Organization, Geneva, Switzerland, 2011.
O'Brien, L. M., Harris, N. R. P., Robinson, A. D., Gostlow, B., Warwick, N., Yang, X., and Pyle, J. A.: Bromocarbons in the tropical marine boundary layer at the Cape Verde Observatory – measurements and modelling, Atmos. Chem. Phys., 9, 9083–9099, https://doi.org/10.5194/acp-9-9083-2009, 2009.
Oram, D. E., Mani, F. S., Laube, J. C., Newland, M. J., Reeves, C. E., Sturges, W. T., Penkett, S. A., Brenninkmeijer, C. A. M., Röckmann, T., and Fraser, P. J.: Long-term tropospheric trend of octafluorocyclobutane (c-C4F8 or PFC-318), Atmos. Chem. Phys., 12, 261–269, https://doi.org/10.5194/acp-12-261-2012, 2012.
Quack, B. and Wallace, D.: Air-sea flux of bromoform: Controls, rates, and implications, Global Biogeochem. Cy., 17, 1023, https://doi.org/10.1029/2002GB001890, 2003.
Riese, M., Ploeger, F., Rap, A., Vogel, B., Konopka, P., Dameris, M., Forster, P., and Foster, P.: Impact of uncertainties in atmospheric mixing on simulated UTLS composition and related radiative effects, J. Geophys. Res., 117, D16305, https://doi.org/10.1029/2012JD017751, 2012.
Schauffler, S. M. Atlas, E. L., Blake, D. R., Flocke, F., Lueb, R. A., Lee-Taylor, J. M., Stroud, V., and Travnicek, W.: Distributions of brominated organic compounds in the troposphere and lower stratosphere, J. Geophys. Res., 104, 21513–21535, https://doi.org/10.1029/1999JD900197, 1999.
Scheele, M. P., Siegmund, P. C., and Van Velthoven, P. F. J.: Sensitivity of trajectories to data resolution and its dependence on the starting point: in or outside a tropopause fold, Meteorol. Appl., 3, 267–273, https://doi.org/10.1002/met.5060030308, 2007.
Schuck, T. J., Brenninkmeijer, C. A. M., Baker, A. K., Slemr, F., von Velthoven, P. F. J., and Zahn, A.: Greenhouse gas relationships in the Indian summer monsoon plume measured by the CARIBIC passenger aircraft, Atmos. Chem. Phys., 10, 3965–3984, https://doi.org/10.5194/acp-10-3965-2010, 2010.
Sinnhuber, B.-M., Sheode, N., Sinnhuber, M., Chipperfield, M. P., and Feng, W.: The contribution of anthropogenic bromine emissions to past stratospheric ozone trends: a modelling study, Atmos. Chem. Phys., 9, 2863–2871, https://doi.org/10.5194/acp-9-2863-2009, 2009.
Sprung, D. and Zahn, A.: Acetone in the upper troposphere/lowermost stratosphere measured by the CARIBIC passenger aircraft: distribution, seasonal cycle, and variability, J. Geophys. Res., 115, 1–12, https://doi.org/10.1029/2009JD012099, 2010.
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