Articles | Volume 21, issue 3
Atmos. Chem. Phys., 21, 1485–1505, 2021
https://doi.org/10.5194/acp-21-1485-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Special issue: The Modular Earth Submodel System (MESSy) (ACP/GMD inter-journal...
Atmos. Chem. Phys., 21, 1485–1505, 2021
https://doi.org/10.5194/acp-21-1485-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
04 Feb 2021
Research article
| 04 Feb 2021
Cold cloud microphysical process rates in a global chemistry–climate model
Sara Bacer et al.
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Simon F. Reifenberg, Anna Martin, Matthias Kohl, Sara Bacer, Zaneta Hamryszczak, Ivan Tadic, Lenard Röder, Daniel J. Crowley, Horst Fischer, Katharina Kaiser, Johannes Schneider, Raphael Dörich, John N. Crowley, Laura Tomsche, Andreas Marsing, Christiane Voigt, Andreas Zahn, Christopher Pöhlker, Bruna A. Holanda, Ovid Krüger, Ulrich Pöschl, Mira Pöhlker, Patrick Jöckel, Marcel Dorf, Ulrich Schumann, Jonathan Williams, Birger Bohn, Joachim Curtius, Hardwig Harder, Hans Schlager, Jos Lelieveld, and Andrea Pozzer
Atmos. Chem. Phys., 22, 10901–10917, https://doi.org/10.5194/acp-22-10901-2022, https://doi.org/10.5194/acp-22-10901-2022, 2022
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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.
Sara Bacer, Fatima Jomaa, Julien Beaumet, Hubert Gallée, Enzo Le Bouëdec, Martin Ménégoz, and Chantal Staquet
Weather Clim. Dynam., 3, 377–389, https://doi.org/10.5194/wcd-3-377-2022, https://doi.org/10.5194/wcd-3-377-2022, 2022
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We study the impact of climate change on wintertime atmospheric blocking over Europe. We focus on the frequency, duration, and size of blocking events. The blocking events are identified via the weather type decomposition methodology. We find that blocking frequency, duration, and size are mostly stationary over the 21st century. Additionally, we compare the blocking size results with the size of the blocking events identified via a different approach using a blocking index.
Domenico Taraborrelli, David Cabrera-Perez, Sara Bacer, Sergey Gromov, Jos Lelieveld, Rolf Sander, and Andrea Pozzer
Atmos. Chem. Phys., 21, 2615–2636, https://doi.org/10.5194/acp-21-2615-2021, https://doi.org/10.5194/acp-21-2615-2021, 2021
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Atmospheric pollutants from anthropogenic activities and biomass burning are usually regarded as ozone precursors. Monocyclic aromatics are no exception. Calculations with a comprehensive atmospheric model are consistent with this view but only for air masses close to pollution source regions. However, the same model predicts that aromatics, when transported to remote areas, may effectively destroy ozone. This loss of tropospheric ozone rivals the one attributed to bromine.
Klaus Klingmüller, Vlassis A. Karydis, Sara Bacer, Georgiy L. Stenchikov, and Jos Lelieveld
Atmos. Chem. Phys., 20, 15285–15295, https://doi.org/10.5194/acp-20-15285-2020, https://doi.org/10.5194/acp-20-15285-2020, 2020
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Particulate air pollution cools the climate and partially masks the greenhouse warming by reflecting sunlight and enhancing the reflection by clouds. The intensity of this cooling depends on interactions between pollution and desert dust within the atmosphere. Our simulations with a global atmospheric chemistry-climate model indicate that these interactions significantly weaken the cooling.
Meryem Tanarhte, Sara Bacer, Susannah M. Burrows, J. Alex Huffman, Kyle M. Pierce, Andrea Pozzer, Roland Sarda-Estève, Nicole J. Savage, and Jos Lelieveld
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2019-251, https://doi.org/10.5194/acp-2019-251, 2019
Publication in ACP not foreseen
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Bioaerosols have been an important topic in atmospheric science in the last two decades. This paper compares different emission parametrizations used in fungal spores modeling and compare their results to two sets of new observational datasets. It emphasises their uncertainties in order to improve their modeling in the future. This comparison is addressed primarily to the scientific community (publishing in ACP) interested in this type of modeling and the related experimental work in this field.
Sara Bacer, Sylvia C. Sullivan, Vlassis A. Karydis, Donifan Barahona, Martina Krämer, Athanasios Nenes, Holger Tost, Alexandra P. Tsimpidi, Jos Lelieveld, and Andrea Pozzer
Geosci. Model Dev., 11, 4021–4041, https://doi.org/10.5194/gmd-11-4021-2018, https://doi.org/10.5194/gmd-11-4021-2018, 2018
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The complexity of ice nucleation mechanisms and aerosol--ice interactions makes their representation still challenging in atmospheric models. We have implemented a comprehensive ice crystal formation parameterization in the global chemistry-climate model EMAC to improve the representation of ice crystal number concentrations. The newly implemented parameterization takes into account processes which were previously neglected by the standard version of the model.
Meryem Tanarhte, Sara Bacer, Susannah M. Burrows, J. Alex Huffman, Kyle M. Pierce, Andrea Pozzer, Roland Sarda-Estève, Nicole J. Savage, and Jos Lelieveld
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2018-361, https://doi.org/10.5194/acp-2018-361, 2018
Revised manuscript not accepted
Vlassis A. Karydis, Alexandra P. Tsimpidi, Sara Bacer, Andrea Pozzer, Athanasios Nenes, and Jos Lelieveld
Atmos. Chem. Phys., 17, 5601–5621, https://doi.org/10.5194/acp-17-5601-2017, https://doi.org/10.5194/acp-17-5601-2017, 2017
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The importance of mineral dust for cloud droplet formation is studied by considering the adsorption activation of insoluble dust particles and the thermodynamic interactions between mineral cations and inorganic anions. This study demonstrates that a comprehensive treatment of the CCN activity of mineral dust and its chemical and thermodynamic interactions with inorganic species by chemistry climate models is important to realistically account for aerosol–chemistry–cloud–climate interaction.
Sara Bacer, Theodoros Christoudias, and Andrea Pozzer
Atmos. Chem. Phys., 16, 15581–15592, https://doi.org/10.5194/acp-16-15581-2016, https://doi.org/10.5194/acp-16-15581-2016, 2016
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We investigate the influence of the North Atlantic Oscillation on atmospheric pollutant transport in the 21st century under a global climate-change scenario, using a coupled atmosphere–chemistry–ocean general circulation model. We find that, at the end of the century, the south-western Mediterranean and northern Africa will see higher pollutant concentrations during positive NAO phases with respect to the past, while a wider part of north Europe will see lower pollutant concentrations.
S. Bacer, T. Christoudias, and A. Pozzer
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acpd-15-33049-2015, https://doi.org/10.5194/acpd-15-33049-2015, 2015
Preprint withdrawn
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We investigate the temporal variability of the North Atlantic Oscillation (NAO) pattern and its relation to the atmospheric dispersion of pollutants in the near past and in the future.
We use a global climate circulation model in order to analyze the NAO signal and its correlation with pollutant concentrations. We find that the NAO is influenced by natural climate variability and that the NAO Indices may be used as indicators of (future) pollutant transport over Europe.
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.
Lenard L. Röder, Patrick Dewald, Clara M. Nussbaumer, Jan Schuladen, John N. Crowley, Jos Lelieveld, and Horst Fischer
EGUsphere, https://doi.org/10.5194/egusphere-2022-1080, https://doi.org/10.5194/egusphere-2022-1080, 2022
This preprint is open for discussion and under review for Atmospheric Measurement Techniques (AMT).
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Field experiments in atmospheric chemistry provide insights into chemical interactions of our atmosphere. However, high data coverage and accuracy is needed to enable further analysis. In this study we explore a statistical method that combines knowledge about the chemical reactions with information from measurements to increase the quality of field experiment data sets. We test the algorithm for several applications and discuss limitations that depend on the specific variable and the dynamics.
Zaneta Hamryszczak, Dirk Dienhart, Bettina Brendel, Roland Rohloff, Daniel Marno, Monica Martinez, Hartwig Harder, Andrea Pozzer, Birger Bohn, Martin Zöger, Jos Lelieveld, and Horst Fischer
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2022-693, https://doi.org/10.5194/acp-2022-693, 2022
Preprint under review for ACP
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Hydrogen peroxide is a key contributor to the oxidative chemistry of the atmosphere through its link to the most prominent oxidants controlling its self-cleansing capacity, HOx. During CAFE-Africa campaign, H2O2 was measured over the Atlantic Ocean and western Africa in August/September 2018. The study gives an overview of the distribution of H2O2 in the upper tropical troposphere and investigates the impact of convective processes in the Intertropical Convergence Zone on the budget of H2O2.
Klaus Klingmüller and Jos Lelieveld
Geosci. Model Dev. Discuss., https://doi.org/10.5194/gmd-2022-232, https://doi.org/10.5194/gmd-2022-232, 2022
Preprint under review for GMD
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Desert dust has significant impacts on climate, public health, infrastructure and ecosystems. The impact assessment requires numerical predictions, which are challenging because the dust emissions are not well known. We present a novel approach using satellite observations and machine learning to more accurately estimate the emissions and to improve the model simulations.
Charlotte M. Beall, Thomas C. J. Hill, Paul J. DeMott, Tobias Köneman, Michael Pikridas, Frank Drewnick, Hartwig Harder, Christopher Pöhlker, Jos Lelieveld, Bettina Weber, Minas Iakovides, Roman Prokeš, Jean Sciare, Meinrat O. Andreae, M. Dale Stokes, and Kimberly A. Prather
Atmos. Chem. Phys., 22, 12607–12627, https://doi.org/10.5194/acp-22-12607-2022, https://doi.org/10.5194/acp-22-12607-2022, 2022
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Ice-nucleating particles (INPs) are rare aerosols that can trigger ice formation in clouds and affect climate-relevant cloud properties such as phase, reflectivity and lifetime. Dust is the dominant INP source, yet few measurements have been reported near major dust sources. We report INP observations within hundreds of kilometers of the biggest dust source regions globally: the Sahara and the Arabian Peninsula. Results show that at temperatures > −15 °C, INPs are dominated by organics.
Mengze Li, Andrea Pozzer, Jos Lelieveld, and Jonathan Williams
Earth Syst. Sci. Data, 14, 4351–4364, https://doi.org/10.5194/essd-14-4351-2022, https://doi.org/10.5194/essd-14-4351-2022, 2022
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We present a northern hemispheric airborne measurement dataset of atmospheric ethane, propane and methane and temporal trends for the time period 2006–2016 in the upper troposphere and lower stratosphere. The growth rates of ethane, methane, and propane in the upper troposphere are -2.24, 0.33, and -0.78 % yr-1, respectively, and in the lower stratosphere they are -3.27, 0.26, and -4.91 % yr-1, respectively, in 2006–2016.
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.
Dirk Dienhart, Bettina Brendel, John N. Crowley, Philipp G. Eger, Hartwig Harder, Monica Martinez, Andrea Pozzer, Roland Rohloff, Jan Schuladen, Sebastian Tauer, Jos Lelieveld, and Horst Fischer
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2022-580, https://doi.org/10.5194/acp-2022-580, 2022
Revised manuscript accepted for ACP
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Formaldehyde and hydroperoxide measurements were performed in the marine boundary layer around the Arabian Peninsula and highlight the Suez Canal and the Arabian (Persian) Gulf as a hotspot of photochemical air pollution. The comparison with the general circulation model EMAC shows rather accurate results of formaldehyde and an overestimation of hydrogen peroxide, which revealed enhanced HOx (=OH+HO2) radicals in the simulation and an underestimation of dry deposition velocites.
Jessica Danker, Odran Sourdeval, Isabel L. McCoy, Robert Wood, and Anna Possner
Atmos. Chem. Phys., 22, 10247–10265, https://doi.org/10.5194/acp-22-10247-2022, https://doi.org/10.5194/acp-22-10247-2022, 2022
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Using spaceborne lidar-radar retrievals, we show that seasonal changes in cloud phase outweigh changes in cloud-phase statistics across cloud morphologies at given cloud-top temperatures. These results show that cloud morphology does not seem to pose a primary constraint on cloud-phase statistics in the Southern Ocean. Meanwhile, larger changes in in-cloud albedo across cloud morphologies are observed in supercooled liquid rather than mixed-phase stratocumuli.
Zaneta T. Hamryszczak, Andrea Pozzer, Florian Obersteiner, Birger Bohn, Benedikt Steil, Jos Lelieveld, and Horst Fischer
Atmos. Chem. Phys., 22, 9483–9497, https://doi.org/10.5194/acp-22-9483-2022, https://doi.org/10.5194/acp-22-9483-2022, 2022
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Hydrogen peroxide plays a pivotal role in the chemistry of the atmosphere. Together with organic hydroperoxides, it forms a reservoir for peroxy radicals, which are known to be the key contributors to the self-cleaning processes of the atmosphere. Hydroperoxides were measured over Europe during the BLUESKY campaign in May–June 2020. The paper gives an overview of the distribution of the species in the troposphere and investigates the impact of wet scavenging and deposition on the budget of H2O2.
Marco Wietzoreck, Marios Kyprianou, Benjamin A. Musa Bandowe, Siddika Celik, John N. Crowley, Frank Drewnick, Philipp Eger, Nils Friedrich, Minas Iakovides, Petr Kukučka, Jan Kuta, Barbora Nežiková, Petra Pokorná, Petra Přibylová, Roman Prokeš, Roland Rohloff, Ivan Tadic, Sebastian Tauer, Jake Wilson, Hartwig Harder, Jos Lelieveld, Ulrich Pöschl, Euripides G. Stephanou, and Gerhard Lammel
Atmos. Chem. Phys., 22, 8739–8766, https://doi.org/10.5194/acp-22-8739-2022, https://doi.org/10.5194/acp-22-8739-2022, 2022
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A unique dataset of concentrations and sources of polycyclic aromatic hydrocarbons (PAHs) and their alkylated, oxygenated and nitrated derivatives, in total 74 individual species, in the marine atmosphere is presented. Exposure to these substances poses a major health risk. We found very low concentrations over the Arabian Sea, while both local and long-range-transported pollution caused elevated levels over the Mediterranean Sea and the Arabian Gulf.
Ovid O. Krüger, Bruna A. Holanda, Sourangsu Chowdhury, Andrea Pozzer, David Walter, Christopher Pöhlker, Maria Dolores Andrés Hernández, John P. Burrows, Christiane Voigt, Jos Lelieveld, Johannes Quaas, Ulrich Pöschl, and Mira L. Pöhlker
Atmos. Chem. Phys., 22, 8683–8699, https://doi.org/10.5194/acp-22-8683-2022, https://doi.org/10.5194/acp-22-8683-2022, 2022
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The abrupt reduction in human activities during the first COVID-19 lockdown created unprecedented atmospheric conditions. We took the opportunity to quantify changes in black carbon (BC) as a major anthropogenic air pollutant. Therefore, we measured BC on board a research aircraft over Europe during the lockdown and compared the results to measurements from 2017. With model simulations we account for different weather conditions and find a lockdown-related decrease in BC of 41 %.
Ryan Vella, Matthew Forrest, Jos Lelieveld, and Holger Tost
Geosci. Model Dev. Discuss., https://doi.org/10.5194/gmd-2022-154, https://doi.org/10.5194/gmd-2022-154, 2022
Revised manuscript under review for GMD
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Biogenic volatile organic compounds (BVOC) are released by vegetation and have a major impact on atmospheric chemistry and aerosol formation. Non-interacting vegetation constraints the majority of numerical models used to estimate global BVOC emissions and thus the effects of changing vegetation on emissions are not addressed. In this work, we replace the offline vegetation with dynamic vegetation states by linking a chemistry-climate model with a global dynamic vegetation model.
Edward Groot and Holger Tost
EGUsphere, https://doi.org/10.5194/egusphere-2022-515, https://doi.org/10.5194/egusphere-2022-515, 2022
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Thunderstorm systems play an important role in the dynamics of the Earth’s atmosphere and some of them form a well organised line: squall lines. Simulations of such squall lines with very small initial perturbations are compared to an unperturbed control simulation. The evolution of perturbations and processes amplifying them are analysed. It is shown that the formation of new secondary thunderstorm cells (after the initial primary cells) directly ahead of the line affects the spread strongly.
Hailing Jia, Johannes Quaas, Edward Gryspeerdt, Christoph Böhm, and Odran Sourdeval
Atmos. Chem. Phys., 22, 7353–7372, https://doi.org/10.5194/acp-22-7353-2022, https://doi.org/10.5194/acp-22-7353-2022, 2022
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Aerosol–cloud interaction is the most uncertain component of the anthropogenic forcing of the climate. By combining satellite and reanalysis data, we show that the strength of the Twomey effect (S) increases remarkably with vertical velocity. Both the confounding effect of aerosol–precipitation interaction and the lack of vertical co-location between aerosol and cloud are found to overestimate S, whereas the retrieval biases in aerosol and cloud appear to underestimate S.
Patrick Dewald, Clara M. Nussbaumer, Jan Schuladen, Akima Ringsdorf, Achim Edtbauer, Horst Fischer, Jonathan Williams, Jos Lelieveld, and John N. Crowley
Atmos. Chem. Phys., 22, 7051–7069, https://doi.org/10.5194/acp-22-7051-2022, https://doi.org/10.5194/acp-22-7051-2022, 2022
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We measured the gas-phase reactivity of the NO3 radical on the summit (825 m a.s.l.) of a semi-rural mountain in southwestern Germany in July 2021. The impact of VOC-induced NO3 losses (mostly monoterpenes) competing with a loss by reaction with NO and photolysis throughout the diel cycle was estimated. Besides chemistry, boundary layer dynamics and plant-physiological processes presumably have a great impact on our observations, which were compared to previous NO3 measurements at the same site.
Dimitris Akritidis, Andrea Pozzer, Johannes Flemming, Antje Inness, Philippe Nédélec, and Prodromos Zanis
Atmos. Chem. Phys., 22, 6275–6289, https://doi.org/10.5194/acp-22-6275-2022, https://doi.org/10.5194/acp-22-6275-2022, 2022
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We perform a process-oriented evaluation of Copernicus Atmosphere Monitoring Service (CAMS) reanalysis (CAMSRA) O3 over Europe using WOUDC (World Ozone and Ultraviolet Radiation Data Centre) ozonesondes and IAGOS (In-service Aircraft for a Global Observing System) aircraft measurements. Chemical data assimilation assists CAMSRA to reproduce the observed O3 increases in the troposphere during the examined folding events, but it mostly results in O3 overestimation in the upper troposphere.
Mohamed Abdelkader, Georgiy Stenchikov, Andrea Pozzer, Holger Tost, and Jos Lelieveld
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2022-177, https://doi.org/10.5194/acp-2022-177, 2022
Revised manuscript accepted for ACP
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We study the effect of injected volcanic ash, water vapor, and SO2 on the development of the volcanic cloud and the stratospheric aerosol optical depth (AOD). Both are sensitive to the initial injection height and to the aging of the volcanic ash shaped by heterogeneous chemistry coupled with the ozone cycle. The manuscript explains the large differences in AOD for different injection scenarios which could improve the estimate of the radiative forcing of volcanic eruptions.
Clara M. Nussbaumer, Andrea Pozzer, Ivan Tadic, Lenard Röder, Florian Obersteiner, Hartwig Harder, Jos Lelieveld, and Horst Fischer
Atmos. Chem. Phys., 22, 6151–6165, https://doi.org/10.5194/acp-22-6151-2022, https://doi.org/10.5194/acp-22-6151-2022, 2022
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The European COVID-19 lockdowns have significantly reduced the emission of primary pollutants such as NOx, which impacts the tropospheric photochemical processes and the abundance of O3. In this study, we present how the lockdowns have affected tropospheric trace gases and ozone production based on in situ observations and modeling simulations. We additionally show that the chemical regime shifted from a transition point to a NOx limitation in the upper troposphere.
Wenyu Sun, Matias Berasategui, Andrea Pozzer, Jos Lelieveld, and John N. Crowley
Atmos. Chem. Phys., 22, 4969–4984, https://doi.org/10.5194/acp-22-4969-2022, https://doi.org/10.5194/acp-22-4969-2022, 2022
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The reaction between OH and SO2 is a termolecular process that in the atmosphere results in the formation of H2SO4 and thus aerosols. We present the first temperature- and pressure-dependent measurements of the rate coefficients in N2. This is also the first study to examine the effects of water vapour on the kinetics of this reaction. Our results indicate the rate coefficient is larger than that recommended by evaluation panels, with deviations of up to 30 % in some parts of the atmosphere.
Sara Bacer, Fatima Jomaa, Julien Beaumet, Hubert Gallée, Enzo Le Bouëdec, Martin Ménégoz, and Chantal Staquet
Weather Clim. Dynam., 3, 377–389, https://doi.org/10.5194/wcd-3-377-2022, https://doi.org/10.5194/wcd-3-377-2022, 2022
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We study the impact of climate change on wintertime atmospheric blocking over Europe. We focus on the frequency, duration, and size of blocking events. The blocking events are identified via the weather type decomposition methodology. We find that blocking frequency, duration, and size are mostly stationary over the 21st century. Additionally, we compare the blocking size results with the size of the blocking events identified via a different approach using a blocking index.
Andrea Pozzer, Simon F. Reifenberg, Vinod Kumar, Bruno Franco, Matthias Kohl, Domenico Taraborrelli, Sergey Gromov, Sebastian Ehrhart, Patrick Jöckel, Rolf Sander, Veronica Fall, Simon Rosanka, Vlassis Karydis, Dimitris Akritidis, Tamara Emmerichs, Monica Crippa, Diego Guizzardi, Johannes W. Kaiser, Lieven Clarisse, Astrid Kiendler-Scharr, Holger Tost, and Alexandra Tsimpidi
Geosci. Model Dev., 15, 2673–2710, https://doi.org/10.5194/gmd-15-2673-2022, https://doi.org/10.5194/gmd-15-2673-2022, 2022
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A newly developed setup of the chemistry general circulation model EMAC (ECHAM5/MESSy for Atmospheric Chemistry) is evaluated here. A comprehensive organic degradation mechanism is used and coupled with a volatility base model.
The results show that the model reproduces most of the tracers and aerosols satisfactorily but shows discrepancies for oxygenated organic gases. It is also shown that this model configuration can be used for further research in atmospheric chemistry.
Guangjie Zheng, Hang Su, Siwen Wang, Andrea Pozzer, and Yafang Cheng
Atmos. Chem. Phys., 22, 47–63, https://doi.org/10.5194/acp-22-47-2022, https://doi.org/10.5194/acp-22-47-2022, 2022
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The recently proposed multiphase buffer theory provides a framework to reconstruct long-term trends and spatial variations in aerosol pH, while non-ideality is a major limitation for its broad applications. Here we proposed a parameterization method to estimate the impact of non-ideality and validated it against long-term observations and global simulations. With this method, the multiphase buffer theory can reproduce well aerosol pH variations estimated by comprehensive thermodynamic models.
Clara M. Nussbaumer, John N. Crowley, Jan Schuladen, Jonathan Williams, Sascha Hafermann, Andreas Reiffs, Raoul Axinte, Hartwig Harder, Cheryl Ernest, Anna Novelli, Katrin Sala, Monica Martinez, Chinmay Mallik, Laura Tomsche, Christian Plass-Dülmer, Birger Bohn, Jos Lelieveld, and Horst Fischer
Atmos. Chem. Phys., 21, 18413–18432, https://doi.org/10.5194/acp-21-18413-2021, https://doi.org/10.5194/acp-21-18413-2021, 2021
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HCHO is an important atmospheric trace gas influencing the photochemical processes in the Earth’s atmosphere, including the budget of HOx and the abundance of tropospheric O3. This research presents the photochemical calculations of HCHO and O3 based on three field campaigns across Europe. We show that HCHO production via the oxidation of only four volatile organic compound precursors, i.e., CH4, CH3CHO, C5H8 and CH3OH, can balance the observed loss at all sites well.
Dirk Dienhart, John N. Crowley, Efstratios Bourtsoukidis, Achim Edtbauer, Philipp G. Eger, Lisa Ernle, Hartwig Harder, Bettina Hottmann, Monica Martinez, Uwe Parchatka, Jean-Daniel Paris, Eva Y. Pfannerstill, Roland Rohloff, Jan Schuladen, Christof Stönner, Ivan Tadic, Sebastian Tauer, Nijing Wang, Jonathan Williams, Jos Lelieveld, and Horst Fischer
Atmos. Chem. Phys., 21, 17373–17388, https://doi.org/10.5194/acp-21-17373-2021, https://doi.org/10.5194/acp-21-17373-2021, 2021
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We present the first ship-based in situ measurements of formaldehyde (HCHO), hydroxyl radicals (OH) and the OH reactivity around the Arabian Peninsula. Regression analysis of the HCHO production rate and the related OH chemistry revealed the regional HCHO yield αeff, which represents the different chemical regimes encountered. Highest values were found for the Arabian Gulf (also known as the Persian Gulf), which highlights this region as a hotspot of photochemical air pollution.
Clara M. Nussbaumer, Uwe Parchatka, Ivan Tadic, Birger Bohn, Daniel Marno, Monica Martinez, Roland Rohloff, Hartwig Harder, Flora Kluge, Klaus Pfeilsticker, Florian Obersteiner, Martin Zöger, Raphael Doerich, John N. Crowley, Jos Lelieveld, and Horst Fischer
Atmos. Meas. Tech., 14, 6759–6776, https://doi.org/10.5194/amt-14-6759-2021, https://doi.org/10.5194/amt-14-6759-2021, 2021
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NO2 plays a central role in atmospheric photochemical processes and requires accurate measurements. This research presents NO2 data obtained via chemiluminescence using a photolytic converter from airborne studies around Cabo Verde and laboratory investigations. We show the limits and error-proneness of a conventional blue light converter in aircraft measurements affected by humidity and NO levels and suggest the use of an alternative quartz converter for more reliable results.
Vlassis A. Karydis, Alexandra P. Tsimpidi, Andrea Pozzer, and Jos Lelieveld
Atmos. Chem. Phys., 21, 14983–15001, https://doi.org/10.5194/acp-21-14983-2021, https://doi.org/10.5194/acp-21-14983-2021, 2021
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Aerosol particle pH is well-buffered by alkaline compounds, notably NH3 and crustal elements. NH3 is found to supply remarkable buffering capacity on a global scale, from the polluted continents to the remote oceans. Potential future changes in agricultural NH3 must be accompanied by strong reductions of SO2 and NOx to avoid particles becoming highly acidic, with implications for human health (aerosol toxicity), ecosystems (acid deposition), clouds, and climate (aerosol hygroscopicity).
Andrea Pozzer
Geosci. Commun., 4, 453–460, https://doi.org/10.5194/gc-4-453-2021, https://doi.org/10.5194/gc-4-453-2021, 2021
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In this paper we investigate the numbers of pages, references and references per page in open-access EGU journals. We showed that, while the number of references and number of pages have been constantly increasing in the period 2010–2020, the number of references per page did not change in the same period. Furthermore, all the journals showed a similar number of references per page, i.e. ~ 3.8 references per page.
Philipp G. Eger, Luc Vereecken, Rolf Sander, Jan Schuladen, Nicolas Sobanski, Horst Fischer, Einar Karu, Jonathan Williams, Ville Vakkari, Tuukka Petäjä, Jos Lelieveld, Andrea Pozzer, and John N. Crowley
Atmos. Chem. Phys., 21, 14333–14349, https://doi.org/10.5194/acp-21-14333-2021, https://doi.org/10.5194/acp-21-14333-2021, 2021
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We determine the impact of pyruvic acid photolysis on the formation of acetaldehyde and peroxy radicals during summer and autumn in the Finnish boreal forest using a data-constrained box model. Our results are dependent on the chosen scenario in which the overall quantum yield and the photolysis products are varied. We highlight that pyruvic acid photolysis can be an important contributor to acetaldehyde and peroxy radical formation in remote, forested regions.
Ralf Weigel, Christoph Mahnke, Manuel Baumgartner, Martina Krämer, Peter Spichtinger, Nicole Spelten, Armin Afchine, Christian Rolf, Silvia Viciani, Francesco D'Amato, Holger Tost, and Stephan Borrmann
Atmos. Chem. Phys., 21, 13455–13481, https://doi.org/10.5194/acp-21-13455-2021, https://doi.org/10.5194/acp-21-13455-2021, 2021
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In July and August 2017, the StratoClim mission took place in Nepal with eight flights of the M-55 Geophysica at up to 20 km in the Asian monsoon anticyclone. New particle formation (NPF) next to cloud ice was detected in situ by abundant nucleation-mode aerosols (> 6 nm) along with ice particles (> 3 µm). NPF was observed mainly below the tropopause, down to 15 % being non-volatile residues. Observed intra-cloud NPF indicates its importance for the composition in the tropical tropopause layer.
Jean-Daniel Paris, Aurélie Riandet, Efstratios Bourtsoukidis, Marc Delmotte, Antoine Berchet, Jonathan Williams, Lisa Ernle, Ivan Tadic, Hartwig Harder, and Jos Lelieveld
Atmos. Chem. Phys., 21, 12443–12462, https://doi.org/10.5194/acp-21-12443-2021, https://doi.org/10.5194/acp-21-12443-2021, 2021
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We measured atmospheric methane and CO2 by ship in the Middle East. We probe the origin of methane with a combination of light alkane measurements and modeling. We find strong influence from nearby oil and gas production over the Arabian Gulf. Comparing our data to inventories indicates that inventories overestimate sources from the upstream gas industry but underestimate emissions from oil extraction and processing. The Red Sea was under a complex mixture of sources due to human activity.
Jennifer Schallock, Christoph Brühl, Christine Bingen, Michael Höpfner, Landon Rieger, and Jos Lelieveld
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2021-654, https://doi.org/10.5194/acp-2021-654, 2021
Revised manuscript under review for ACP
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This paper presents model simulations of stratospheric aerosols with a focus on explosive volcanic eruptions. Using occulation and limb-based satellite instruments with vertical profiles of sulfur dioxide and aerosol extinction, we characterised the influence of volcanic aerosols for the period between 1990–2019. We established a volcanic sulfur emission inventory that includes more than 500 eruptions. Our results show that also smaller eruptions can contribute to the stratospheric aerosol layer.
Patrick Dewald, Raphael Dörich, Jan Schuladen, Jos Lelieveld, and John N. Crowley
Atmos. Meas. Tech., 14, 5501–5519, https://doi.org/10.5194/amt-14-5501-2021, https://doi.org/10.5194/amt-14-5501-2021, 2021
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Organic nitrates generated from the reaction between isoprene and the nitrate radical (ISOP-NITs) were detected via their thermal dissociation in heated quartz inlets to nitrogen dioxide monitored by cavity ring-down spectroscopy. The temperature-dependent dissociation profiles of ISOP-NITs in the presence of ozone (O3) are broad in contrast to narrow profiles of common reference compounds. We demonstrate that this broadening is caused by O3-assisted reactions of ISOP-NITs on quartz surfaces.
Raphael Dörich, Philipp Eger, Jos Lelieveld, and John N. Crowley
Atmos. Meas. Tech., 14, 5319–5332, https://doi.org/10.5194/amt-14-5319-2021, https://doi.org/10.5194/amt-14-5319-2021, 2021
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We demonstrate in laboratory experiments that the formation of IOx anions (formed in reactions of I− with O3) or acetate anions (formed e.g. by the reaction of I− with peracetic acid) results in unexpected sensitivity of an iodide chemical ionisation mass spectrometer (I-CIMS) to HNO3 at a mass-to-charge ratio of 62. This helps explain observations of apparent high daytime levels of N2O5. Airborne measurements using I-CIMS confirm these conclusions.
Vinod Kumar, Julia Remmers, Steffen Beirle, Joachim Fallmann, Astrid Kerkweg, Jos Lelieveld, Mariano Mertens, Andrea Pozzer, Benedikt Steil, Marc Barra, Holger Tost, and Thomas Wagner
Atmos. Meas. Tech., 14, 5241–5269, https://doi.org/10.5194/amt-14-5241-2021, https://doi.org/10.5194/amt-14-5241-2021, 2021
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We present high-resolution regional atmospheric chemistry model simulations focused around Germany. We highlight the importance of spatial resolution of the model itself as well as the input emissions inventory and short-scale temporal variability of emissions for simulations. We propose a consistent approach for evaluating the simulated vertical distribution of NO2 using MAX-DOAS measurements while also considering its spatial sensitivity volume and change in sensitivity within this volume.
Simon Rosanka, Bruno Franco, Lieven Clarisse, Pierre-François Coheur, Andrea Pozzer, Andreas Wahner, and Domenico Taraborrelli
Atmos. Chem. Phys., 21, 11257–11288, https://doi.org/10.5194/acp-21-11257-2021, https://doi.org/10.5194/acp-21-11257-2021, 2021
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The strong El Niño in 2015 led to a particular dry season in Indonesia and favoured severe peatland fires. The smouldering conditions of these fires and the high carbon content of peat resulted in high volatile organic compound (VOC) emissions. By using a comprehensive atmospheric model, we show that these emissions have a significant impact on the tropospheric composition and oxidation capacity. These emissions are transported into to the lower stratosphere, resulting in a depletion of ozone.
Klaus Klingmüller and Jos Lelieveld
Geosci. Model Dev., 14, 4429–4441, https://doi.org/10.5194/gmd-14-4429-2021, https://doi.org/10.5194/gmd-14-4429-2021, 2021
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Soil moisture is of great importance for weather and climate. We present a machine learning model that produces accurate predictions of satellite-observed surface soil moisture, based on meteorological data from a climate model. It can be used as soil moisture parametrisation in climate models and to produce comprehensive global soil moisture datasets. Moreover, it may motivate similar applications of machine learning in climate science.
Tamara Emmerichs, Bruno Franco, Catherine Wespes, Vinod Kumar, Andrea Pozzer, Simon Rosanka, and Domenico Taraborrelli
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2021-584, https://doi.org/10.5194/acp-2021-584, 2021
Revised manuscript not accepted
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Near-surface ozone is a harmful air pollutant and it is strongly affected by radical reactions and surface-atmosphere exchanges which in turn are modulated, directly and indirectly, by weather. Understanding the impact of weather on ozone, and air quality, is thus important also in view of weather extremes. The inclusion of additional ozone-weather links in the global model yields a 2-fold reduction of the ozone bias towards satellite observations.
Ivan Tadic, Clara M. Nussbaumer, Birger Bohn, Hartwig Harder, Daniel Marno, Monica Martinez, Florian Obersteiner, Uwe Parchatka, Andrea Pozzer, Roland Rohloff, Martin Zöger, Jos Lelieveld, and Horst Fischer
Atmos. Chem. Phys., 21, 8195–8211, https://doi.org/10.5194/acp-21-8195-2021, https://doi.org/10.5194/acp-21-8195-2021, 2021
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Although mechanisms of tropospheric ozone (O3) formation are well understood, studies reporting on ozone formation derived from field measurements are challenging and remain sparse in number. We use airborne measurements to quantify nitric oxide (NO) and O3 distributions in the upper troposphere over the Atlantic Ocean and western Africa and compare our measurements to model simulations. Our results show that NO and ozone formation are greatest over the tropical areas of western Africa.
Clara M. Nussbaumer, Ivan Tadic, Dirk Dienhart, Nijing Wang, Achim Edtbauer, Lisa Ernle, Jonathan Williams, Florian Obersteiner, Isidoro Gutiérrez-Álvarez, Hartwig Harder, Jos Lelieveld, and Horst Fischer
Atmos. Chem. Phys., 21, 7933–7945, https://doi.org/10.5194/acp-21-7933-2021, https://doi.org/10.5194/acp-21-7933-2021, 2021
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Lightning over continental and coastal areas is frequent and accompanied by deep convection, while lightning over marine areas and particularly in tropical cyclones is rare. This research presents in situ observations of the tropical storm Florence 2018 near Cabo Verde. We show the absence of lightning in the tropical storm despite the occurrence of deep convective processes by atmospheric trace gas measurements of O3, NO, CO, H2O2, DMS and CH2I.
Nils Friedrich, Philipp Eger, Justin Shenolikar, Nicolas Sobanski, Jan Schuladen, Dirk Dienhart, Bettina Hottmann, Ivan Tadic, Horst Fischer, Monica Martinez, Roland Rohloff, Sebastian Tauer, Hartwig Harder, Eva Y. Pfannerstill, Nijing Wang, Jonathan Williams, James Brooks, Frank Drewnick, Hang Su, Guo Li, Yafang Cheng, Jos Lelieveld, and John N. Crowley
Atmos. Chem. Phys., 21, 7473–7498, https://doi.org/10.5194/acp-21-7473-2021, https://doi.org/10.5194/acp-21-7473-2021, 2021
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This paper uses NOx and NOz measurements from the 2017 AQABA ship campaign in the Mediterranean Sea and around the Arabian Peninsula to examine the influence e.g. of emissions from shipping and oil and gas production. Night-time losses of NOx dominated in the Arabian Gulf and in the Red Sea, whereas daytime losses were more important in the Mediterranean Sea. Nitric acid and organic nitrates were the most prevalent components of NOz.
Jaydeep Singh, Narendra Singh, Narendra Ojha, Amit Sharma, Andrea Pozzer, Nadimpally Kiran Kumar, Kunjukrishnapillai Rajeev, Sachin S. Gunthe, and V. Rao Kotamarthi
Geosci. Model Dev., 14, 1427–1443, https://doi.org/10.5194/gmd-14-1427-2021, https://doi.org/10.5194/gmd-14-1427-2021, 2021
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Atmospheric models often have limitations in simulating the geographically complex and climatically important central Himalayan region. In this direction, we have performed regional modeling at high resolutions to improve the simulation of meteorology and dynamics through a better representation of the topography. The study has implications for further model applications to investigate the effects of anthropogenic pressure over the Himalaya.
Chaim I. Garfinkel, Ohad Harari, Shlomi Ziskin Ziv, Jian Rao, Olaf Morgenstern, Guang Zeng, Simone Tilmes, Douglas Kinnison, Fiona M. O'Connor, Neal Butchart, Makoto Deushi, Patrick Jöckel, Andrea Pozzer, and Sean Davis
Atmos. Chem. Phys., 21, 3725–3740, https://doi.org/10.5194/acp-21-3725-2021, https://doi.org/10.5194/acp-21-3725-2021, 2021
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Water vapor is the dominant greenhouse gas in the atmosphere, and El Niño is the dominant mode of variability in the ocean–atmosphere system. The connection between El Niño and water vapor above ~ 17 km is unclear, with single-model studies reaching a range of conclusions. This study examines this connection in 12 different models. While there are substantial differences among the models, all models appear to capture the fundamental physical processes correctly.
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.
Domenico Taraborrelli, David Cabrera-Perez, Sara Bacer, Sergey Gromov, Jos Lelieveld, Rolf Sander, and Andrea Pozzer
Atmos. Chem. Phys., 21, 2615–2636, https://doi.org/10.5194/acp-21-2615-2021, https://doi.org/10.5194/acp-21-2615-2021, 2021
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Atmospheric pollutants from anthropogenic activities and biomass burning are usually regarded as ozone precursors. Monocyclic aromatics are no exception. Calculations with a comprehensive atmospheric model are consistent with this view but only for air masses close to pollution source regions. However, the same model predicts that aromatics, when transported to remote areas, may effectively destroy ozone. This loss of tropospheric ozone rivals the one attributed to bromine.
Klaus Klingmüller, Vlassis A. Karydis, Sara Bacer, Georgiy L. Stenchikov, and Jos Lelieveld
Atmos. Chem. Phys., 20, 15285–15295, https://doi.org/10.5194/acp-20-15285-2020, https://doi.org/10.5194/acp-20-15285-2020, 2020
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Particulate air pollution cools the climate and partially masks the greenhouse warming by reflecting sunlight and enhancing the reflection by clouds. The intensity of this cooling depends on interactions between pollution and desert dust within the atmosphere. Our simulations with a global atmospheric chemistry-climate model indicate that these interactions significantly weaken the cooling.
Johannes Quaas, Antti Arola, Brian Cairns, Matthew Christensen, Hartwig Deneke, Annica M. L. Ekman, Graham Feingold, Ann Fridlind, Edward Gryspeerdt, Otto Hasekamp, Zhanqing Li, Antti Lipponen, Po-Lun Ma, Johannes Mülmenstädt, Athanasios Nenes, Joyce E. Penner, Daniel Rosenfeld, Roland Schrödner, Kenneth Sinclair, Odran Sourdeval, Philip Stier, Matthias Tesche, Bastiaan van Diedenhoven, and Manfred Wendisch
Atmos. Chem. Phys., 20, 15079–15099, https://doi.org/10.5194/acp-20-15079-2020, https://doi.org/10.5194/acp-20-15079-2020, 2020
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Anthropogenic pollution particles – aerosols – serve as cloud condensation nuclei and thus increase cloud droplet concentration and the clouds' reflection of sunlight (a cooling effect on climate). This Twomey effect is poorly constrained by models and requires satellite data for better quantification. The review summarizes the challenges in properly doing so and outlines avenues for progress towards a better use of aerosol retrievals and better retrievals of droplet concentrations.
Edward Groot and Holger Tost
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2020-1142, https://doi.org/10.5194/acp-2020-1142, 2020
Publication in ACP not foreseen
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Sensitivities and variability of upper tropospheric flow (~10 km height) resulting immediately and as a direct consequence of (thunder)storm activity have been modeled in detail down to resolutions of 100–200 m and explored for different (organisation/) storm types. It is shown that the amount of water condensation explains much of emerging variability in upper atmospheric flow. Part of the effects on the nearby upper atmospheric flow is suggested to be explained by (organisation/) storm type.
Matias Berasategui, Damien Amedro, Luc Vereecken, Jos Lelieveld, and John N. Crowley
Atmos. Chem. Phys., 20, 13541–13555, https://doi.org/10.5194/acp-20-13541-2020, https://doi.org/10.5194/acp-20-13541-2020, 2020
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Peracetic acid is one of the most abundant organic peroxides in the atmosphere. We combine experiments and theory to show that peracetic acid reacts orders of magnitude more slowly with OH than presently accepted, which results in a significant extension of its atmospheric lifetime.
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.
Martina Krämer, Christian Rolf, Nicole Spelten, Armin Afchine, David Fahey, Eric Jensen, Sergey Khaykin, Thomas Kuhn, Paul Lawson, Alexey Lykov, Laura L. Pan, Martin Riese, Andrew Rollins, Fred Stroh, Troy Thornberry, Veronika Wolf, Sarah Woods, Peter Spichtinger, Johannes Quaas, and Odran Sourdeval
Atmos. Chem. Phys., 20, 12569–12608, https://doi.org/10.5194/acp-20-12569-2020, https://doi.org/10.5194/acp-20-12569-2020, 2020
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To improve the representations of cirrus clouds in climate predictions, extended knowledge of their properties and geographical distribution is required. This study presents extensive airborne in situ and satellite remote sensing climatologies of cirrus and humidity, which serve as a guide to cirrus clouds. Further, exemplary radiative characteristics of cirrus types and also in situ observations of tropical tropopause layer cirrus and humidity in the Asian monsoon anticyclone are shown.
Nils Friedrich, Ivan Tadic, Jan Schuladen, James Brooks, Eoghan Darbyshire, Frank Drewnick, Horst Fischer, Jos Lelieveld, and John N. Crowley
Atmos. Meas. Tech., 13, 5739–5761, https://doi.org/10.5194/amt-13-5739-2020, https://doi.org/10.5194/amt-13-5739-2020, 2020
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We present a new instrument for the measurement of NOx and NOy based on a combination of the thermal dissociation of NOy to NOx and cavity ring-down spectroscopic detection of NO2. It features a denuder to separate the contributions of gas-phase and particulate nitrates to NOy. We provide a detailed characterization of the instrument and briefly outline results from first deployments.
Nijing Wang, Achim Edtbauer, Christof Stönner, Andrea Pozzer, Efstratios Bourtsoukidis, Lisa Ernle, Dirk Dienhart, Bettina Hottmann, Horst Fischer, Jan Schuladen, John N. Crowley, Jean-Daniel Paris, Jos Lelieveld, and Jonathan Williams
Atmos. Chem. Phys., 20, 10807–10829, https://doi.org/10.5194/acp-20-10807-2020, https://doi.org/10.5194/acp-20-10807-2020, 2020
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Carbonyl compounds were measured on a ship travelling around the Arabian Peninsula in summer 2017, crossing both highly polluted and extremely clean regions of the marine boundary layer. We investigated the sources and sinks of carbonyls. The results from a global model showed a significant model underestimation for acetaldehyde, a molecule that can influence regional air chemistry. By adding a diurnal oceanic source, the model estimation was highly improved.
Patrick Dewald, Jonathan M. Liebmann, Nils Friedrich, Justin Shenolikar, Jan Schuladen, Franz Rohrer, David Reimer, Ralf Tillmann, Anna Novelli, Changmin Cho, Kangming Xu, Rupert Holzinger, François Bernard, Li Zhou, Wahid Mellouki, Steven S. Brown, Hendrik Fuchs, Jos Lelieveld, and John N. Crowley
Atmos. Chem. Phys., 20, 10459–10475, https://doi.org/10.5194/acp-20-10459-2020, https://doi.org/10.5194/acp-20-10459-2020, 2020
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We present direct measurements of NO3 reactivity resulting from the oxidation of isoprene by NO3 during an intensive simulation chamber study. Measurements were in excellent agreement with values calculated from measured isoprene amounts and the rate coefficient for the reaction of NO3 with isoprene. Comparison of the measurement with NO3 reactivities from non-steady-state and model calculations suggests that isoprene-derived RO2 and HO2 radicals account to ~ 50 % of overall NO3 losses.
Dominik Stolzenburg, Mario Simon, Ananth Ranjithkumar, Andreas Kürten, Katrianne Lehtipalo, Hamish Gordon, Sebastian Ehrhart, Henning Finkenzeller, Lukas Pichelstorfer, Tuomo Nieminen, Xu-Cheng He, Sophia Brilke, Mao Xiao, António Amorim, Rima Baalbaki, Andrea Baccarini, Lisa Beck, Steffen Bräkling, Lucía Caudillo Murillo, Dexian Chen, Biwu Chu, Lubna Dada, António Dias, Josef Dommen, Jonathan Duplissy, Imad El Haddad, Lukas Fischer, Loic Gonzalez Carracedo, Martin Heinritzi, Changhyuk Kim, Theodore K. Koenig, Weimeng Kong, Houssni Lamkaddam, Chuan Ping Lee, Markus Leiminger, Zijun Li, Vladimir Makhmutov, Hanna E. Manninen, Guillaume Marie, Ruby Marten, Tatjana Müller, Wei Nie, Eva Partoll, Tuukka Petäjä, Joschka Pfeifer, Maxim Philippov, Matti P. Rissanen, Birte Rörup, Siegfried Schobesberger, Simone Schuchmann, Jiali Shen, Mikko Sipilä, Gerhard Steiner, Yuri Stozhkov, Christian Tauber, Yee Jun Tham, António Tomé, Miguel Vazquez-Pufleau, Andrea C. Wagner, Mingyi Wang, Yonghong Wang, Stefan K. Weber, Daniela Wimmer, Peter J. Wlasits, Yusheng Wu, Qing Ye, Marcel Zauner-Wieczorek, Urs Baltensperger, Kenneth S. Carslaw, Joachim Curtius, Neil M. Donahue, Richard C. Flagan, Armin Hansel, Markku Kulmala, Jos Lelieveld, Rainer Volkamer, Jasper Kirkby, and Paul M. Winkler
Atmos. Chem. Phys., 20, 7359–7372, https://doi.org/10.5194/acp-20-7359-2020, https://doi.org/10.5194/acp-20-7359-2020, 2020
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Sulfuric acid is a major atmospheric vapour for aerosol formation. If new particles grow fast enough, they can act as cloud droplet seeds or affect air quality. In a controlled laboratory set-up, we demonstrate that van der Waals forces enhance growth from sulfuric acid. We disentangle the effects of ammonia, ions and particle hydration, presenting a complete picture of sulfuric acid growth from molecular clusters onwards. In a climate model, we show its influence on the global aerosol budget.
Harald Rybka and Holger Tost
Geosci. Model Dev., 13, 2671–2694, https://doi.org/10.5194/gmd-13-2671-2020, https://doi.org/10.5194/gmd-13-2671-2020, 2020
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Simulating cloud processes and their interactions with their environment is one of the biggest challenges in atmospheric science. This study couples a cloud-resolving model with a global climate model to improve the representation of small-scale processes for climate simulations. Unlike conventional approaches, tropical precipitation is better simulated with the new model setup. However, the diurnal cycle of precipitation and cloud amounts can be significantly influenced by the chosen setup.
Ivan Tadic, John N. Crowley, Dirk Dienhart, Philipp Eger, Hartwig Harder, Bettina Hottmann, Monica Martinez, Uwe Parchatka, Jean-Daniel Paris, Andrea Pozzer, Roland Rohloff, Jan Schuladen, Justin Shenolikar, Sebastian Tauer, Jos Lelieveld, and Horst Fischer
Atmos. Chem. Phys., 20, 6769–6787, https://doi.org/10.5194/acp-20-6769-2020, https://doi.org/10.5194/acp-20-6769-2020, 2020
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We present shipborne observations of NO, NO2, O3, HCHO, OH, HO2, H2O and the actinic flux obtained in the marine boundary layer (MBL) around the Arabian Peninsula during the summer 2017 AQABA ship campaign. NOx (NO+NO2) and O3 observations clearly showed anthropogenic influence in the MBL around the Arabian Peninsula. The observations were also used to calculate net O3 production in the MBL around the Arabian Peninsula, which was greatest over the northern Red Sea, Oman Gulf and Arabian Gulf.
Daniel Marno, Cheryl Ernest, Korbinian Hens, Umar Javed, Thomas Klimach, Monica Martinez, Markus Rudolf, Jos Lelieveld, and Hartwig Harder
Atmos. Meas. Tech., 13, 2711–2731, https://doi.org/10.5194/amt-13-2711-2020, https://doi.org/10.5194/amt-13-2711-2020, 2020
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In this study, a calibration device for OH and HO2 instruments is characterized at pressures of 275 to 1000 mbar, allowing instrument pressure sensitivity to be quantified to an accuracy of 22 % (1σ). Computational fluid dynamic simulations supporting the understanding of interactions between generated HOx and the instrument inlet led to enhanced determination of factors affecting instrument sensitivity.
Achim Edtbauer, Christof Stönner, Eva Y. Pfannerstill, Matias Berasategui, David Walter, John N. Crowley, Jos Lelieveld, and Jonathan Williams
Atmos. Chem. Phys., 20, 6081–6094, https://doi.org/10.5194/acp-20-6081-2020, https://doi.org/10.5194/acp-20-6081-2020, 2020
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Marine regions where deep nutrient-rich water is pushed towards the surface are called upwelling regions. In these nutrient-rich waters large algal blooms form which are the basis of the marine food web. We measured methane sulfonamide, a molecule containing sulfur and nitrogen, for the first time in ambient air and could show that the origin of this emission is an algal bloom near the Somalia upwelling. Sulfur-containing compounds from algae can promote particle formation over the oceans.
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.
Montserrat Costa-Surós, Odran Sourdeval, Claudia Acquistapace, Holger Baars, Cintia Carbajal Henken, Christa Genz, Jonas Hesemann, Cristofer Jimenez, Marcel König, Jan Kretzschmar, Nils Madenach, Catrin I. Meyer, Roland Schrödner, Patric Seifert, Fabian Senf, Matthias Brueck, Guido Cioni, Jan Frederik Engels, Kerstin Fieg, Ksenia Gorges, Rieke Heinze, Pavan Kumar Siligam, Ulrike Burkhardt, Susanne Crewell, Corinna Hoose, Axel Seifert, Ina Tegen, and Johannes Quaas
Atmos. Chem. Phys., 20, 5657–5678, https://doi.org/10.5194/acp-20-5657-2020, https://doi.org/10.5194/acp-20-5657-2020, 2020
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The impact of anthropogenic aerosols on clouds is a key uncertainty in climate change. This study analyses large-domain simulations with a new high-resolution model to investigate the differences in clouds between 1985 and 2013 comparing multiple observational datasets. The differences in aerosol and in cloud droplet concentrations are clearly detectable. For other quantities, the detection and attribution proved difficult, despite a substantial impact on the Earth's energy budget.
Philipp G. Eger, Jan Schuladen, Nicolas Sobanski, Horst Fischer, Einar Karu, Jonathan Williams, Matthieu Riva, Qiaozhi Zha, Mikael Ehn, Lauriane L. J. Quéléver, Simon Schallhart, Jos Lelieveld, and John N. Crowley
Atmos. Chem. Phys., 20, 3697–3711, https://doi.org/10.5194/acp-20-3697-2020, https://doi.org/10.5194/acp-20-3697-2020, 2020
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Pyruvic acid, CH3C(O)C(O)OH, is an organic acid of biogenic origin that plays a crucial role in plant metabolism, is present in tropospheric air in both gas-phase and aerosol-phase, and is implicated in the formation of secondary organic aerosols. From the first gas-phase measurements of pyruvic acid in the Finnish boreal forest in September 2016 we derive its source strength and discuss potential sources and sinks, with a focus on the relevance of gas-phase pyruvic acid for radical chemistry.
Matthew Forrest, Holger Tost, Jos Lelieveld, and Thomas Hickler
Geosci. Model Dev., 13, 1285–1309, https://doi.org/10.5194/gmd-13-1285-2020, https://doi.org/10.5194/gmd-13-1285-2020, 2020
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We have integrated the LPJ-GUESS dynamic global vegetation model into the EMAC atmospheric chemistry-enabled GCM (general circulation model). This combined framework will enable the investigation of many land–atmosphere interactions and feedbacks with state-of-the-art simulation models. Initial results show that using the climate produced by EMAC together with LPJ-GUESS produces an acceptable representation of the global vegetation.
Damien Amedro, Matias Berasategui, Arne J. C. Bunkan, Andrea Pozzer, Jos Lelieveld, and John N. Crowley
Atmos. Chem. Phys., 20, 3091–3105, https://doi.org/10.5194/acp-20-3091-2020, https://doi.org/10.5194/acp-20-3091-2020, 2020
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Our laboratory experiments show that the rate coefficient for the termolecular reaction between OH and NO2 is enhanced in the presence of water vapour. Using a chemistry transport model we show that our new parameterization of the temperature, pressure, and bath-gas dependence of this reaction has a significant impact on, for example, NOx and the HNO2 / NO2 ratio when compared to present recommendations.
Matias Berasategui, Damien Amedro, Achim Edtbauer, Jonathan Williams, Jos Lelieveld, and John N. Crowley
Atmos. Chem. Phys., 20, 2695–2707, https://doi.org/10.5194/acp-20-2695-2020, https://doi.org/10.5194/acp-20-2695-2020, 2020
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We have determined the rate coefficient and mechanism for the reaction of the OH radical with methane sulphonamide, a trace gas which has recently been found in the atmosphere. The rate coefficient is 1.4 × 10−13 cm3 molec.−1 s−1, which indicates a tropospheric lifetime of > 2 months. The observation of CO, CO2, SO2, HNO3, HCOOH, and N2O products enabled us to derive a detailed reaction mechanism for the reaction, which proceeds predominantly by H abstraction from the CH3 group.
Claudia Unglaub, Karoline Block, Johannes Mülmenstädt, Odran Sourdeval, and Johannes Quaas
Atmos. Chem. Phys., 20, 2407–2418, https://doi.org/10.5194/acp-20-2407-2020, https://doi.org/10.5194/acp-20-2407-2020, 2020
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In cloud research, it is necessary to classify clouds. The World Meteorological Organization proposes distinguishing stratiform and cumuliform clouds in three altitude layers. The paper explains why previous approaches to classify clouds fail for many applications and proposes a new classification on the basis of new approaches for satellite retrievals to derive cloud-base height, in combination with cloud inhomogeneity. It is demonstrated that this discriminates cloud characteristics well.
Julie M. Nicely, Bryan N. Duncan, Thomas F. Hanisco, Glenn M. Wolfe, Ross J. Salawitch, Makoto Deushi, Amund S. Haslerud, Patrick Jöckel, Béatrice Josse, Douglas E. Kinnison, Andrew Klekociuk, Michael E. Manyin, Virginie Marécal, Olaf Morgenstern, Lee T. Murray, Gunnar Myhre, Luke D. Oman, Giovanni Pitari, Andrea Pozzer, Ilaria Quaglia, Laura E. Revell, Eugene Rozanov, Andrea Stenke, Kane Stone, Susan Strahan, Simone Tilmes, Holger Tost, Daniel M. Westervelt, and Guang Zeng
Atmos. Chem. Phys., 20, 1341–1361, https://doi.org/10.5194/acp-20-1341-2020, https://doi.org/10.5194/acp-20-1341-2020, 2020
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Differences in methane lifetime among global models are large and poorly understood. We use a neural network method and simulations from the Chemistry Climate Model Initiative to quantify the factors influencing methane lifetime spread among models and variations over time. UV photolysis, tropospheric ozone, and nitrogen oxides drive large model differences, while the same factors plus specific humidity contribute to a decreasing trend in methane lifetime between 1980 and 2015.
Georgia Sotiropoulou, Sylvia Sullivan, Julien Savre, Gary Lloyd, Thomas Lachlan-Cope, Annica M. L. Ekman, and Athanasios Nenes
Atmos. Chem. Phys., 20, 1301–1316, https://doi.org/10.5194/acp-20-1301-2020, https://doi.org/10.5194/acp-20-1301-2020, 2020
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Arctic clouds constitute a large source of uncertainty in predictions of future climate. Observations indicate that the number concentration of cloud ice crystals exceeds the concentration of aerosols that can act as ice-nucleating particles (INPs). We show that ice multiplication due to mechanical break-up upon collisions between the few primary ice crystals (formed from INPs) can explain the discrepancy. Including a description of the process in climate models can improve cloud representation.
Lei Gu, Jie Chen, Jiabo Yin, Sylvia C. Sullivan, Hui-Min Wang, Shenglian Guo, Liping Zhang, and Jong-Suk Kim
Hydrol. Earth Syst. Sci., 24, 451–472, https://doi.org/10.5194/hess-24-451-2020, https://doi.org/10.5194/hess-24-451-2020, 2020
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Focusing on the multifaceted nature of droughts, this study quantifies the change in global drought risks for 1.5 and 2.0 °C warming trajectories by a multi-model ensemble under three representative concentration pathways (RCP2.6, 4.5 and 8.5). Socioeconomic exposures are investigated by incorporating the dynamic shared socioeconomic pathways (SSPs) into the drought impact assessment. The results show that even the ambitious 1.5 °C warming level can cause substantial increases on the global scale.
Ying Chen, Yafang Cheng, Nan Ma, Chao Wei, Liang Ran, Ralf Wolke, Johannes Größ, Qiaoqiao Wang, Andrea Pozzer, Hugo A. C. Denier van der Gon, Gerald Spindler, Jos Lelieveld, Ina Tegen, Hang Su, and Alfred Wiedensohler
Atmos. Chem. Phys., 20, 771–786, https://doi.org/10.5194/acp-20-771-2020, https://doi.org/10.5194/acp-20-771-2020, 2020
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Particulate nitrate is one of the most important climate cooling agents. Our results show that interaction with sea-salt aerosol can shift nitrate to larger sized particles (redistribution effect), weakening its direct cooling effect. The modelling results indicate strong redistribution over coastal and offshore regions worldwide as well as continental Europe. Improving the consideration of the redistribution effect in global models fosters a better understanding of climate change.
Dimitris Akritidis, Andrea Pozzer, and Prodromos Zanis
Atmos. Chem. Phys., 19, 14387–14401, https://doi.org/10.5194/acp-19-14387-2019, https://doi.org/10.5194/acp-19-14387-2019, 2019
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We investigate the impact of future climate change under the RCP6.0 scenario on tropopause folds and tropospheric ozone, using a transient EMAC simulation and a tropopause fold detection algorithm. A strengthening of ozone stratosphere-to-troposphere transport (STT) is projected for the future, resulting in an increase in upper- and middle-tropospheric ozone. The maxima of future ozone STT increases are mainly projected for regions where tropopause folds are expected to occur more frequently.
Nils Madenach, Cintia Carbajal Henken, René Preusker, Odran Sourdeval, and Jürgen Fischer
Atmos. Chem. Phys., 19, 13535–13546, https://doi.org/10.5194/acp-19-13535-2019, https://doi.org/10.5194/acp-19-13535-2019, 2019
Philipp G. Eger, Nils Friedrich, Jan Schuladen, Justin Shenolikar, Horst Fischer, Ivan Tadic, Hartwig Harder, Monica Martinez, Roland Rohloff, Sebastian Tauer, Frank Drewnick, Friederike Fachinger, James Brooks, Eoghan Darbyshire, Jean Sciare, Michael Pikridas, Jos Lelieveld, and John N. Crowley
Atmos. Chem. Phys., 19, 12121–12140, https://doi.org/10.5194/acp-19-12121-2019, https://doi.org/10.5194/acp-19-12121-2019, 2019
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Shipborne measurements of nitryl chloride (ClNO2) were made during the AQABA (Air Quality and climate change in the Arabian BAsin) ship campaign in summer 2017. The dataset includes measurements over the Mediterranean Sea and around the Arabian Peninsula with observed mixing ratios ranging from the limit of detection to 600 pptv. We examined the regional variability in the generation of ClNO2 and its importance for Cl atom generation in a marine boundary layer influenced by ships and industry.
Horst Fischer, Raoul Axinte, Heiko Bozem, John N. Crowley, Cheryl Ernest, Stefan Gilge, Sascha Hafermann, Hartwig Harder, Korbinian Hens, Ruud H. H. Janssen, Rainer Königstedt, Dagmar Kubistin, Chinmay Mallik, Monica Martinez, Anna Novelli, Uwe Parchatka, Christian Plass-Dülmer, Andrea Pozzer, Eric Regelin, Andreas Reiffs, Torsten Schmidt, Jan Schuladen, and Jos Lelieveld
Atmos. Chem. Phys., 19, 11953–11968, https://doi.org/10.5194/acp-19-11953-2019, https://doi.org/10.5194/acp-19-11953-2019, 2019
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We use in situ observations of H2O2 to study the interplay between photochemistry, transport and deposition processes. The data were obtained during five ground-based field campaigns across Europe. A budget calculation indicates that the photochemical production rate was much larger than photochemical loss and that dry deposition is the dominant loss process. To reproduce the change in H2O2 mixing ratios after sunrise, a variable contribution of entrainment from the residual layer is required.
Matthias Kippenberger, Gerhard Schuster, Jos Lelieveld, and John N. Crowley
Atmos. Chem. Phys., 19, 11939–11951, https://doi.org/10.5194/acp-19-11939-2019, https://doi.org/10.5194/acp-19-11939-2019, 2019
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We investigated the uptake of several trace gases to growing ice surfaces at temperatures relevant to cirrus clouds. HCl, a strong inorganic acid that ionises at the surface, was efficiently trapped in the growing ice, whereas oxidised organic trace gases, which attach to ice by hydrogen bonding, were not. HCl can be efficiently and rapidly removed from the gas phase in supersaturated ice clouds.
Jianzhong Ma, Christoph Brühl, Qianshan He, Benedikt Steil, Vlassis A. Karydis, Klaus Klingmüller, Holger Tost, Bin Chen, Yufang Jin, Ningwei Liu, Xiangde Xu, Peng Yan, Xiuji Zhou, Kamal Abdelrahman, Andrea Pozzer, and Jos Lelieveld
Atmos. Chem. Phys., 19, 11587–11612, https://doi.org/10.5194/acp-19-11587-2019, https://doi.org/10.5194/acp-19-11587-2019, 2019
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We find a pronounced maximum in aerosol extinction in the upper troposphere and lower stratosphere over the Tibetan Plateau during the Asian summer monsoon, caused mainly by mineral dust emitted from the northern Tibetan Plateau and slope area, lofted to and accumulating within the anticyclonic circulation. Mineral dust, water-soluble compounds, such as nitrate and sulfate, and associated liquid water dominate aerosol extinction around the tropopause within the Asian summer monsoon anticyclone.
Eva Y. Pfannerstill, Nijing Wang, Achim Edtbauer, Efstratios Bourtsoukidis, John N. Crowley, Dirk Dienhart, Philipp G. Eger, Lisa Ernle, Horst Fischer, Bettina Hottmann, Jean-Daniel Paris, Christof Stönner, Ivan Tadic, David Walter, Jos Lelieveld, and Jonathan Williams
Atmos. Chem. Phys., 19, 11501–11523, https://doi.org/10.5194/acp-19-11501-2019, https://doi.org/10.5194/acp-19-11501-2019, 2019
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The Arabian Peninsula is a global hot spot of ozone pollution. Our measurements, made on a ship in summer 2017, indicate underlying reasons. Despite being at sea, we observed ozone-forming reactive trace gases (measured as so-called total OH reactivity) comparable to highly populated urban regions in amount and composition. This is due to strong emissions from oil extraction and ship traffic. These emissions were quickly converted to ozone due to intense solar irradiation and high temperatures.
Mega Octaviani, Holger Tost, and Gerhard Lammel
Geosci. Model Dev., 12, 3585–3607, https://doi.org/10.5194/gmd-12-3585-2019, https://doi.org/10.5194/gmd-12-3585-2019, 2019
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This work presents a submodel description for the atmospheric cycling and air–surface exchange processes of semivolatile organic compounds. The submodel is meant to be applied within a global atmospheric chemistry–climate model. The simulation results for polycyclic aromatic hydrocarbons confirm progress in modelling semivolatile species, verified by comparison with surface monitoring data. The significance of new modelling features for tracer distributions was quantified in a sensitivity study.
Jonathan Liebmann, Nicolas Sobanski, Jan Schuladen, Einar Karu, Heidi Hellén, Hannele Hakola, Qiaozhi Zha, Mikael Ehn, Matthieu Riva, Liine Heikkinen, Jonathan Williams, Horst Fischer, Jos Lelieveld, and John N. Crowley
Atmos. Chem. Phys., 19, 10391–10403, https://doi.org/10.5194/acp-19-10391-2019, https://doi.org/10.5194/acp-19-10391-2019, 2019
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The formation of alkyl nitrates in the boreal forest was dominated by reactions of the NO3 radical with terpenes, both during the day and the night, with fewer contributions from OH and ozone. The alkyl nitrates formed had lifetimes on the order of 2 h, reflecting efficient loss via uptake to aerosol and deposition.
Erin Evoy, Adrian M. Maclean, Grazia Rovelli, Ying Li, Alexandra P. Tsimpidi, Vlassis A. Karydis, Saeid Kamal, Jos Lelieveld, Manabu Shiraiwa, Jonathan P. Reid, and Allan K. Bertram
Atmos. Chem. Phys., 19, 10073–10085, https://doi.org/10.5194/acp-19-10073-2019, https://doi.org/10.5194/acp-19-10073-2019, 2019
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We measured the diffusion rates of organic molecules in a number of proxies for secondary organic aerosol (SOA) and compared measured diffusion with predictions from two relations: the Stokes–Einstein relation and a fractional Stokes–Einstein relation. The fractional relation does a better job of predicting diffusion rates in this case. Output from an atmospheric model shows that mixing times predicted using the two relations differ by up to 1 order of magnitude at an altitude of ~ 3 km.
Ohad Harari, Chaim I. Garfinkel, Shlomi Ziskin Ziv, Olaf Morgenstern, Guang Zeng, Simone Tilmes, Douglas Kinnison, Makoto Deushi, Patrick Jöckel, Andrea Pozzer, Fiona M. O'Connor, and Sean Davis
Atmos. Chem. Phys., 19, 9253–9268, https://doi.org/10.5194/acp-19-9253-2019, https://doi.org/10.5194/acp-19-9253-2019, 2019
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Ozone depletion in the Antarctic has been shown to influence surface conditions, but the effects of ozone depletion in the Arctic on surface climate are unclear. We show that Arctic ozone does influence surface climate in both polar regions and tropical regions, though the proximate cause of these surface impacts is not yet clear.
Klaus Klingmüller, Jos Lelieveld, Vlassis A. Karydis, and Georgiy L. Stenchikov
Atmos. Chem. Phys., 19, 7397–7408, https://doi.org/10.5194/acp-19-7397-2019, https://doi.org/10.5194/acp-19-7397-2019, 2019
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Within the atmosphere, desert dust and anthropogenic pollution are mixed and interact, which affects the abundance and optical properties of the particulate matter. This results in an anthropogenic climate forcing associated with mineral dust notwithstanding the natural origin of most aeolian dust. With a global chemistry–climate model, we estimate this forcing to represent a considerable fraction of the total dust forcing.
Efstratios Bourtsoukidis, Lisa Ernle, John N. Crowley, Jos Lelieveld, Jean-Daniel Paris, Andrea Pozzer, David Walter, and Jonathan Williams
Atmos. Chem. Phys., 19, 7209–7232, https://doi.org/10.5194/acp-19-7209-2019, https://doi.org/10.5194/acp-19-7209-2019, 2019
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We report on results that demonstrate the utility of non-methane hydrocarbons as source/sink identification tracers while providing their mixing ratios around the Arabian Peninsula. By introducing novel data-analysis approaches, we establish a new method for separating associated and non-associated (with liquids) gases. We formulate a relationship between hydrocarbon oxidative pairs that can be used to evaluate the relative abundance of the hydroxyl and chlorine radicals in the troposphere.
Vincent Huijnen, Andrea Pozzer, Joaquim Arteta, Guy Brasseur, Idir Bouarar, Simon Chabrillat, Yves Christophe, Thierno Doumbia, Johannes Flemming, Jonathan Guth, Béatrice Josse, Vlassis A. Karydis, Virginie Marécal, and Sophie Pelletier
Geosci. Model Dev., 12, 1725–1752, https://doi.org/10.5194/gmd-12-1725-2019, https://doi.org/10.5194/gmd-12-1725-2019, 2019
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We report on an evaluation of tropospheric ozone and its precursor gases in three atmospheric chemistry versions as implemented in ECMWF’s Integrated Forecasting System (IFS), referred to as IFS(CB05BASCOE), IFS(MOZART) and IFS(MOCAGE). This configuration of having various chemistry versions within IFS provides a quantification of uncertainties in CAMS trace gas products that are induced by chemistry modelling.
Edward Gryspeerdt, Tom Goren, Odran Sourdeval, Johannes Quaas, Johannes Mülmenstädt, Sudhakar Dipu, Claudia Unglaub, Andrew Gettelman, and Matthew Christensen
Atmos. Chem. Phys., 19, 5331–5347, https://doi.org/10.5194/acp-19-5331-2019, https://doi.org/10.5194/acp-19-5331-2019, 2019
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The liquid water path (LWP) is the strongest control on cloud albedo, such that a small change in LWP can have a large radiative impact. By changing the droplet number concentration (Nd) aerosols may be able to change the LWP, but the sign and magnitude of the effect is unclear. This work uses satellite data to investigate the relationship between Nd and LWP at a global scale and in response to large aerosol perturbations, suggesting that a strong decrease in LWP at high Nd may be overestimated.
Meryem Tanarhte, Sara Bacer, Susannah M. Burrows, J. Alex Huffman, Kyle M. Pierce, Andrea Pozzer, Roland Sarda-Estève, Nicole J. Savage, and Jos Lelieveld
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2019-251, https://doi.org/10.5194/acp-2019-251, 2019
Publication in ACP not foreseen
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Bioaerosols have been an important topic in atmospheric science in the last two decades. This paper compares different emission parametrizations used in fungal spores modeling and compare their results to two sets of new observational datasets. It emphasises their uncertainties in order to improve their modeling in the future. This comparison is addressed primarily to the scientific community (publishing in ACP) interested in this type of modeling and the related experimental work in this field.
Rolf Sander, Andreas Baumgaertner, David Cabrera-Perez, Franziska Frank, Sergey Gromov, Jens-Uwe Grooß, Hartwig Harder, Vincent Huijnen, Patrick Jöckel, Vlassis A. Karydis, Kyle E. Niemeyer, Andrea Pozzer, Hella Riede, Martin G. Schultz, Domenico Taraborrelli, and Sebastian Tauer
Geosci. Model Dev., 12, 1365–1385, https://doi.org/10.5194/gmd-12-1365-2019, https://doi.org/10.5194/gmd-12-1365-2019, 2019
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We present the atmospheric chemistry box model CAABA/MECCA which
now includes a number of new features: skeletal mechanism
reduction, the MOM chemical mechanism for volatile organic
compounds, an option to include reactions from the Master
Chemical Mechanism (MCM) and other chemical mechanisms, updated
isotope tagging, improved and new photolysis modules, and the new
feature of coexisting multiple chemistry mechanisms.
CAABA/MECCA is a community model published under the GPL.
Philipp G. Eger, Frank Helleis, Gerhard Schuster, Gavin J. Phillips, Jos Lelieveld, and John N. Crowley
Atmos. Meas. Tech., 12, 1935–1954, https://doi.org/10.5194/amt-12-1935-2019, https://doi.org/10.5194/amt-12-1935-2019, 2019
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We present a chemical ionization quadrupole mass spectrometer (CI-QMS) with a novel discharge ion source. In addition to the expected detection of PAN, peracetic acid and ClNO2, the instrument is also sensitive to SO2, HCl and acetic acid through ion chemistry unique for our ion source. We present ionization schemes along with illustrative datasets from field campaigns underlining the potential of the CI-QMS as an alternative to polonium, especially for application in the marine boundary layer.
Christoph Böhm, Odran Sourdeval, Johannes Mülmenstädt, Johannes Quaas, and Susanne Crewell
Atmos. Meas. Tech., 12, 1841–1860, https://doi.org/10.5194/amt-12-1841-2019, https://doi.org/10.5194/amt-12-1841-2019, 2019
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The cloud base height (CBH) is important for air traffic, for describing the energy budget of the Earth and for other applications. Ground-based CBH measurements are only available for individual sites and mostly limited to land. Satellites are a powerful tool for global coverage. While the cloud top height is derived operationally, the derivation of CBH from space is more difficult as the clouds hide their base. Here, we present a method to retrieve the CBH from multi-angle satellite data.
Laura Tomsche, Andrea Pozzer, Narendra Ojha, Uwe Parchatka, Jos Lelieveld, and Horst Fischer
Atmos. Chem. Phys., 19, 1915–1939, https://doi.org/10.5194/acp-19-1915-2019, https://doi.org/10.5194/acp-19-1915-2019, 2019
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The Asian monsoon anticyclone (AMA) is an annual phenomenon in the northern hemispheric upper troposphere (UT) and lower stratosphere. We performed in situ measurements of carbon monoxide (CO) and methane (CH4) in the monsoon outflow region and in background air in the UT (Mediterranean, Arabian Peninsula, Arabian Sea) using airborne optical absorption spectroscopy during the Oxidation Mechanism Observations mission (summer 2015). The trace gases increased within the AMA, particularly CH4.
J. Christopher Kaiser, Johannes Hendricks, Mattia Righi, Patrick Jöckel, Holger Tost, Konrad Kandler, Bernadett Weinzierl, Daniel Sauer, Katharina Heimerl, Joshua P. Schwarz, Anne E. Perring, and Thomas Popp
Geosci. Model Dev., 12, 541–579, https://doi.org/10.5194/gmd-12-541-2019, https://doi.org/10.5194/gmd-12-541-2019, 2019
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The implementation of the aerosol microphysics submodel MADE3 into the global atmospheric chemistry model EMAC is described and evaluated against an extensive pool of observational data, focusing on aerosol mass and number concentrations, size distributions, composition, and optical properties. EMAC (MADE3) is able to reproduce main aerosol properties reasonably well, in line with the performance of other global aerosol models.
Yingying Yan, David Cabrera-Perez, Jintai Lin, Andrea Pozzer, Lu Hu, Dylan B. Millet, William C. Porter, and Jos Lelieveld
Geosci. Model Dev., 12, 111–130, https://doi.org/10.5194/gmd-12-111-2019, https://doi.org/10.5194/gmd-12-111-2019, 2019
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The GEOS-Chem model has been updated with the SAPRC-11 aromatics chemical mechanism to evaluate global and regional effects of aromatics on tropospheric oxidation capacity. Our results reveal relatively slight changes in ozone, hydroxyl radical, and nitrogen oxides on a global mean basis (1–4 %), although remarkable regional differences (5–20 %) exist near the source regions. Improved representation of aromatics is important to simulate the tropospheric oxidation.
Johannes Mülmenstädt, Odran Sourdeval, David S. Henderson, Tristan S. L'Ecuyer, Claudia Unglaub, Leonore Jungandreas, Christoph Böhm, Lynn M. Russell, and Johannes Quaas
Earth Syst. Sci. Data, 10, 2279–2293, https://doi.org/10.5194/essd-10-2279-2018, https://doi.org/10.5194/essd-10-2279-2018, 2018
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One of the key pieces of information about a cloud is how high its base is. Unlike cloud top, cloud base is hard to observe from a satellite perspective – the cloud blocks the view. But without using satellites, it is difficult to compile global datasets. Here we describe how we worked around the limitations of a cloud-detecting laser satellite to observe global cloud base heights. This dataset will expand our knowledge of the cloudy atmosphere and its interaction with the planetary surface.
Sebastian Ehrhart, Eimear M. Dunne, Hanna E. Manninen, Tuomo Nieminen, Jos Lelieveld, and Andrea Pozzer
Geosci. Model Dev., 11, 4987–5001, https://doi.org/10.5194/gmd-11-4987-2018, https://doi.org/10.5194/gmd-11-4987-2018, 2018
Sylvia C. Sullivan, Christian Barthlott, Jonathan Crosier, Ilya Zhukov, Athanasios Nenes, and Corinna Hoose
Atmos. Chem. Phys., 18, 16461–16480, https://doi.org/10.5194/acp-18-16461-2018, https://doi.org/10.5194/acp-18-16461-2018, 2018
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Ice crystal formation in clouds can occur via thermodynamic nucleation, but also via mechanical collisions between pre-existing crystals or co-existing droplets. When descriptions of this mechanical ice generation are implemented into the COSMO weather model, we find that the contributions to crystal number from thermodynamic and mechanical processes are of the same order. Mechanical ice generation also intensifies differences in precipitation intensity between dynamic and quiescent regions.
Odran Sourdeval, Edward Gryspeerdt, Martina Krämer, Tom Goren, Julien Delanoë, Armin Afchine, Friederike Hemmer, and Johannes Quaas
Atmos. Chem. Phys., 18, 14327–14350, https://doi.org/10.5194/acp-18-14327-2018, https://doi.org/10.5194/acp-18-14327-2018, 2018
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The number concentration of ice crystals (Ni) is a key cloud property that remains very uncertain due to difficulties in determining it using satellites. This lack of global observational constraints limits our ability to constrain this property in models responsible for predicting future climate. This pair of papers fills this gap by showing and analyzing the first rigorously evaluated global climatology of Ni, leading to new information shedding light on the processes that control high clouds.
Edward Gryspeerdt, Odran Sourdeval, Johannes Quaas, Julien Delanoë, Martina Krämer, and Philipp Kühne
Atmos. Chem. Phys., 18, 14351–14370, https://doi.org/10.5194/acp-18-14351-2018, https://doi.org/10.5194/acp-18-14351-2018, 2018
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The concentration of ice crystals in a cloud affects both the properties and the life cycle of the cloud. This work uses a new satellite retrieval to investigate controls on the ice crystal concentration at a global scale. Both temperature and vertical wind speed in a cloud have a strong impact on the concentration of ice crystals. The ice crystal number is also related to the aerosol environment; defining this relation opens up new ways to investigate human impacts on clouds and the climate.
Sara Bacer, Sylvia C. Sullivan, Vlassis A. Karydis, Donifan Barahona, Martina Krämer, Athanasios Nenes, Holger Tost, Alexandra P. Tsimpidi, Jos Lelieveld, and Andrea Pozzer
Geosci. Model Dev., 11, 4021–4041, https://doi.org/10.5194/gmd-11-4021-2018, https://doi.org/10.5194/gmd-11-4021-2018, 2018
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The complexity of ice nucleation mechanisms and aerosol--ice interactions makes their representation still challenging in atmospheric models. We have implemented a comprehensive ice crystal formation parameterization in the global chemistry-climate model EMAC to improve the representation of ice crystal number concentrations. The newly implemented parameterization takes into account processes which were previously neglected by the standard version of the model.
John N. Crowley, Nicolas Pouvesle, Gavin J. Phillips, Raoul Axinte, Horst Fischer, Tuukka Petäjä, Anke Nölscher, Jonathan Williams, Korbinian Hens, Hartwig Harder, Monica Martinez-Harder, Anna Novelli, Dagmar Kubistin, Birger Bohn, and Jos Lelieveld
Atmos. Chem. Phys., 18, 13457–13479, https://doi.org/10.5194/acp-18-13457-2018, https://doi.org/10.5194/acp-18-13457-2018, 2018
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Simultaneous observations of PAA, PAN and H2O2 are used to provide insight into processes influencing the HOx chemistry of the boreal forest, including two biomass-burning-impacted periods. A significant contribution from photolytic HOx sources was included in a box model analysis to align model predictions with measurements. The model predicts high levels of organic peroxy radicals, also at night-time.
Jonathan M. Liebmann, Jennifer B. A. Muller, Dagmar Kubistin, Anja Claude, Robert Holla, Christian Plass-Dülmer, Jos Lelieveld, and John N. Crowley
Atmos. Chem. Phys., 18, 12045–12059, https://doi.org/10.5194/acp-18-12045-2018, https://doi.org/10.5194/acp-18-12045-2018, 2018
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We present direct measurements of the summertime total reactivity (inverse lifetime) of NO3 towards organic trace gases at a rural mountain site. High daytime and low night-time values were found. The reactivity was dominated by reaction with monoterpenes and sufficiently high to compete with photolysis and reaction with NO during daytime. NO3 radical measurements from one night are presented. For the first time, direct measurements of OH and NO3 reactivity are compared.
Alexandra P. Tsimpidi, Vlassis A. Karydis, Andrea Pozzer, Spyros N. Pandis, and Jos Lelieveld
Geosci. Model Dev., 11, 3369–3389, https://doi.org/10.5194/gmd-11-3369-2018, https://doi.org/10.5194/gmd-11-3369-2018, 2018
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A new module, ORACLE 2-D, that calculates the concentrations of surrogate organic species in two-dimensional space defined by volatility and oxygen-to-carbon ratio has been developed and evaluated. ORACLE 2-D uses a simple photochemical aging scheme that efficiently simulates the net effects of fragmentation and functionalization. ORACLE 2-D can be used to compute the ability of organic particles to act as cloud condensation nuclei and serves as a tool to quantify their climatic impact.
Zacharias Marinou Nikolaou, Jyh-Yuan Chen, Yiannis Proestos, Jos Lelieveld, and Rolf Sander
Geosci. Model Dev., 11, 3391–3407, https://doi.org/10.5194/gmd-11-3391-2018, https://doi.org/10.5194/gmd-11-3391-2018, 2018
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Chemistry is an important component of the atmosphere that describes many important physical processes. However, atmospheric chemical mechanisms include hundreds of species and reactions, posing a significant computational load. In this work, we use a powerful reduction method in order to develop a computationally faster chemical mechanism from a detailed mechanism. This enables accelerated simulations, which can be used to examine a wider range of processes in increased detail.
Maarten Krol, Marco de Bruine, Lars Killaars, Huug Ouwersloot, Andrea Pozzer, Yi Yin, Frederic Chevallier, Philippe Bousquet, Prabir Patra, Dmitry Belikov, Shamil Maksyutov, Sandip Dhomse, Wuhu Feng, and Martyn P. Chipperfield
Geosci. Model Dev., 11, 3109–3130, https://doi.org/10.5194/gmd-11-3109-2018, https://doi.org/10.5194/gmd-11-3109-2018, 2018
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The TransCom inter-comparison project regularly carries out studies to quantify errors in simulated atmospheric transport. This paper presents the first results of an age of air (AoA) inter-comparison of six global transport models. Following a protocol, six models simulated five tracers from which atmospheric transport times can easily be deduced. Results highlight that inter-model differences associated with atmospheric transport are still large and require further analysis.
Chinmay Mallik, Laura Tomsche, Efstratios Bourtsoukidis, John N. Crowley, Bettina Derstroff, Horst Fischer, Sascha Hafermann, Imke Hüser, Umar Javed, Stephan Keßel, Jos Lelieveld, Monica Martinez, Hannah Meusel, Anna Novelli, Gavin J. Phillips, Andrea Pozzer, Andreas Reiffs, Rolf Sander, Domenico Taraborrelli, Carina Sauvage, Jan Schuladen, Hang Su, Jonathan Williams, and Hartwig Harder
Atmos. Chem. Phys., 18, 10825–10847, https://doi.org/10.5194/acp-18-10825-2018, https://doi.org/10.5194/acp-18-10825-2018, 2018
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OH and HO2 control the transformation of air pollutants and O3 formation. Their implication for air quality over the climatically sensitive Mediterranean region was studied during a field campaign in Cyprus. Production of OH, HO2, and recycled OH was lower in aged marine air masses. Box model simulations of OH and HO2 agreed with measurements except at high terpene concentrations when model RO2 due to terpenes caused large HO2 loss. Autoxidation schemes for RO2 improved the agreement.
Daniel P. Grosvenor, Odran Sourdeval, and Robert Wood
Atmos. Meas. Tech., 11, 4273–4289, https://doi.org/10.5194/amt-11-4273-2018, https://doi.org/10.5194/amt-11-4273-2018, 2018
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We provide a parameterized correction to the retrieval of cloud effective radius from satellite instruments to account for the assumption that the retrieved value is representative of that at cloud top, whereas in reality it is representative of that lower down. The error leads to errors (which we quantify) in the retrieved cloud droplet concentrations of up to 38 % for stratocumulus regions and also to liquid water path errors, both of which can be corrected using our parameterizations.
Aristeidis K. Georgoulias, Athanasios Tsikerdekis, Vassilis Amiridis, Eleni Marinou, Angela Benedetti, Prodromos Zanis, Georgia Alexandri, Lucia Mona, Konstantinos A. Kourtidis, and Jos Lelieveld
Atmos. Chem. Phys., 18, 8601–8620, https://doi.org/10.5194/acp-18-8601-2018, https://doi.org/10.5194/acp-18-8601-2018, 2018
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In this work, the MACC reanalysis dust product is evaluated over Europe, Northern Africa and the Middle East using the EARLINET-optimized CALIOP/CALIPSO pure dust satellite-based product LIVAS (2007–2012). As dust plays a determinant role in processes related to weather and climate, human healt, and the economy, it is obvious that adequately simulating the amount of dust and its optical properties is essential. Our results could be used as a reference in future climate model evaluations.
Meryem Tanarhte, Sara Bacer, Susannah M. Burrows, J. Alex Huffman, Kyle M. Pierce, Andrea Pozzer, Roland Sarda-Estève, Nicole J. Savage, and Jos Lelieveld
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2018-361, https://doi.org/10.5194/acp-2018-361, 2018
Revised manuscript not accepted
Yingying Yan, Andrea Pozzer, Narendra Ojha, Jintai Lin, and Jos Lelieveld
Atmos. Chem. Phys., 18, 5589–5605, https://doi.org/10.5194/acp-18-5589-2018, https://doi.org/10.5194/acp-18-5589-2018, 2018
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Surface-based measurements from the EMEP network and EMAC model simulations are used to estimate the European surface ozone changes over 1995–2014. It shows a significantly decreasing trend in the 95th percentile ozone concentrations, while increasing in the 5th percentile ozone. Sensitivity simulations and statistical analysis show that a decrease in European anthropogenic emissions had contrasting effects on surface ozone trends between the 95th and 5th percentile levels.
Klaus Klingmüller, Swen Metzger, Mohamed Abdelkader, Vlassis A. Karydis, Georgiy L. Stenchikov, Andrea Pozzer, and Jos Lelieveld
Geosci. Model Dev., 11, 989–1008, https://doi.org/10.5194/gmd-11-989-2018, https://doi.org/10.5194/gmd-11-989-2018, 2018
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More than 1 billion tons of mineral dust particles are raised into the atmosphere every year, which has a significant impact on climate, society and ecosystems. The location, time and amount of dust emissions depend on surface and wind conditions. In the atmospheric chemistry–climate model EMAC, we have updated the relevant surface data and equations. Our validation shows that the updates substantially improve the agreement of model results and observations.
Jonathan Liebmann, Einar Karu, Nicolas Sobanski, Jan Schuladen, Mikael Ehn, Simon Schallhart, Lauriane Quéléver, Heidi Hellen, Hannele Hakola, Thorsten Hoffmann, Jonathan Williams, Horst Fischer, Jos Lelieveld, and John N. Crowley
Atmos. Chem. Phys., 18, 3799–3815, https://doi.org/10.5194/acp-18-3799-2018, https://doi.org/10.5194/acp-18-3799-2018, 2018
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Using a newly developed experimental setup, we have made the first direct measurements (during autumn 2016) of NO3 reactivity in the Finnish boreal forest. The NO3 reactivity was generally very high (maximum value of 0.94/s) so that daytime reaction with organics was a substantial fraction of the NO3 loss. Observations of biogenic hydrocarbons (BVOCs) suggested a dominant role for monoterpenes in determining the NO3 reactivity, which displayed a strong vertical gradient between 8.5 and 25 m.
Katrin Dulitz, Damien Amedro, Terry J. Dillon, Andrea Pozzer, and John N. Crowley
Atmos. Chem. Phys., 18, 2381–2394, https://doi.org/10.5194/acp-18-2381-2018, https://doi.org/10.5194/acp-18-2381-2018, 2018
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The reaction between the OH radical and HNO3 represents an important route for the release of NOx (NO and NO2) from HNO3, the most important NOx reservoir in many parts of the atmosphere. In our laboratory study, we have generated an extensive, high-quality set of rate coefficients for this reaction at different temperatures and pressures and used these to derive a new parameterisation of the rate coefficient for atmospheric modelling.
Sylvia C. Sullivan, Corinna Hoose, Alexei Kiselev, Thomas Leisner, and Athanasios Nenes
Atmos. Chem. Phys., 18, 1593–1610, https://doi.org/10.5194/acp-18-1593-2018, https://doi.org/10.5194/acp-18-1593-2018, 2018
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Ice multiplication (IM) processes can have a profound impact on cloud and precipitation development but are poorly understood. Here we study whether a lower limit of ice nuclei exists to initiate IM. The lower limit is found to be extremely low (0.01 per liter or less). A counterintuitive but profound conclusion thus emerges: IM requires cloud formation around a thermodynamic
sweet spotand is sensitive to fluctuations in cloud condensation nuclei concentration alone.
Hannah Meusel, Alexandra Tamm, Uwe Kuhn, Dianming Wu, Anna Lena Leifke, Sabine Fiedler, Nina Ruckteschler, Petya Yordanova, Naama Lang-Yona, Mira Pöhlker, Jos Lelieveld, Thorsten Hoffmann, Ulrich Pöschl, Hang Su, Bettina Weber, and Yafang Cheng
Atmos. Chem. Phys., 18, 799–813, https://doi.org/10.5194/acp-18-799-2018, https://doi.org/10.5194/acp-18-799-2018, 2018
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The photolysis of nitrous acid (HONO) forms the OH radical. However, not all sources are known. Recent studies showed that HONO can be emitted from soil but they did not evaluate the importance to the HONO budget. In this work HONO emissions from 43 soil and biological soil crust samples from Cyprus were measured in a dynamic chamber and extrapolated to the real atmosphere. A large fraction of the local missing source (published earlier; Meusel et al., 2016) could be assigned to soil emissions.
Efstratios Bourtsoukidis, Frank Helleis, Laura Tomsche, Horst Fischer, Rolf Hofmann, Jos Lelieveld, and Jonathan Williams
Atmos. Meas. Tech., 10, 5089–5105, https://doi.org/10.5194/amt-10-5089-2017, https://doi.org/10.5194/amt-10-5089-2017, 2017
Amit Sharma, Narendra Ojha, Andrea Pozzer, Kathleen A. Mar, Gufran Beig, Jos Lelieveld, and Sachin S. Gunthe
Atmos. Chem. Phys., 17, 14393–14413, https://doi.org/10.5194/acp-17-14393-2017, https://doi.org/10.5194/acp-17-14393-2017, 2017
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We evaluate the numerical simulations of surface ozone during pre-monsoon season against a network of stations including clean, rural and polluted urban environments in the south Asian region. Significant effects of the employed emission inventory and chemical mechanism on the simulated ozone are found during the noon hours of intense photochemistry. The presented evaluation on the diurnal timescale would have implications for assessing ozone buildup and impacts on human health and crop yields.
Huisheng Bian, Mian Chin, Didier A. Hauglustaine, Michael Schulz, Gunnar Myhre, Susanne E. Bauer, Marianne T. Lund, Vlassis A. Karydis, Tom L. Kucsera, Xiaohua Pan, Andrea Pozzer, Ragnhild B. Skeie, Stephen D. Steenrod, Kengo Sudo, Kostas Tsigaridis, Alexandra P. Tsimpidi, and Svetlana G. Tsyro
Atmos. Chem. Phys., 17, 12911–12940, https://doi.org/10.5194/acp-17-12911-2017, https://doi.org/10.5194/acp-17-12911-2017, 2017
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Atmospheric nitrate contributes notably to total aerosol mass in the present day and is likely to be more important over the next century, with a projected decline in SO2 and NOx emissions and increase in NH3 emissions. This paper investigates atmospheric nitrate using multiple global models and measurements. The study is part of the AeroCom phase III activity. The study is the first attempt to look at global atmospheric nitrate simulation at physical and chemical process levels.
Andrea Pozzer, Alexandra P. Tsimpidi, Vlassis A. Karydis, Alexander de Meij, and Jos Lelieveld
Atmos. Chem. Phys., 17, 12813–12826, https://doi.org/10.5194/acp-17-12813-2017, https://doi.org/10.5194/acp-17-12813-2017, 2017
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This study shows that agricultural emissions are important for air quality and their reduction can effectively reduce the concentration of fine particles and their associated premature mortality. Therefore, emission control policies, especially in North America and Europe, should also involve strong ammonia emission decreases to optimally reduce fine-particle concentration.
David Cabrera-Perez, Domenico Taraborrelli, Jos Lelieveld, Thorsten Hoffmann, and Andrea Pozzer
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2017-928, https://doi.org/10.5194/acp-2017-928, 2017
Revised manuscript not accepted
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Aromatic compounds are present in rural and urban atmospheres. The aim of this work is to disentangle the impacts of these compounds in different important atmospheric chemical species with the help of a numerical model. Aromatics have low impact OH, NOx and Ozone concentrations in the global scale (below 4 %). The impact however is larger in the regional scale (up to 10 %). The largest impact is in glyoxal and NO3 concentrations, with changes up to 10 % globally and 40 % regionally.
Heiko Bozem, Andrea Pozzer, Hartwig Harder, Monica Martinez, Jonathan Williams, Jos Lelieveld, and Horst Fischer
Atmos. Chem. Phys., 17, 11835–11848, https://doi.org/10.5194/acp-17-11835-2017, https://doi.org/10.5194/acp-17-11835-2017, 2017
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We present a case study of deep convection over Germany in July 2007 within the framework of the HOOVER II project. Airborne in situ measurements within the in- and outflow regions of an isolated thunderstorm provide a unique data set to study the influence of deep convection on the transport efficiency of soluble and insoluble trace gases. Despite their high solubility HCHO and H2O2 show enhanced concentrations in the outflow presumably due to degassing from cloud droplets during freezing.
Hannah Meusel, Yasin Elshorbany, Uwe Kuhn, Thorsten Bartels-Rausch, Kathrin Reinmuth-Selzle, Christopher J. Kampf, Guo Li, Xiaoxiang Wang, Jos Lelieveld, Ulrich Pöschl, Thorsten Hoffmann, Hang Su, Markus Ammann, and Yafang Cheng
Atmos. Chem. Phys., 17, 11819–11833, https://doi.org/10.5194/acp-17-11819-2017, https://doi.org/10.5194/acp-17-11819-2017, 2017
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In this study we investigated protein nitration and decomposition by light in the presence of NO2 via flow tube measurements. Nitrated proteins have an enhanced allergenic potential but so far nitration was only studied in dark conditions. Under irradiated conditions we found that proteins predominantly decompose while forming nitrous acid (HONO) an important precursor of the OH radical. Unlike other studies on heterogeneous NO2 conversion we found a stable HONO formation over a long period.
Heiko Bozem, Tim M. Butler, Mark G. Lawrence, Hartwig Harder, Monica Martinez, Dagmar Kubistin, Jos Lelieveld, and Horst Fischer
Atmos. Chem. Phys., 17, 10565–10582, https://doi.org/10.5194/acp-17-10565-2017, https://doi.org/10.5194/acp-17-10565-2017, 2017
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We present airborne measurements and model simulations in the tropics and mid-latitudes during GABRIEL and HOOVER, respectively. Based only on in situ data net ozone formation/destruction tendencies (NOPR) are calculated and compared to a 3-D chemistry transport model. The NOPR is positive in the continental boundary layer and the upper troposphere above 6 km. In the marine boundary layer and the middle troposphere ozone destruction prevails. Fresh convection shows strong net ozone formation.
Bettina Derstroff, Imke Hüser, Efstratios Bourtsoukidis, John N. Crowley, Horst Fischer, Sergey Gromov, Hartwig Harder, Ruud H. H. Janssen, Jürgen Kesselmeier, Jos Lelieveld, Chinmay Mallik, Monica Martinez, Anna Novelli, Uwe Parchatka, Gavin J. Phillips, Rolf Sander, Carina Sauvage, Jan Schuladen, Christof Stönner, Laura Tomsche, and Jonathan Williams
Atmos. Chem. Phys., 17, 9547–9566, https://doi.org/10.5194/acp-17-9547-2017, https://doi.org/10.5194/acp-17-9547-2017, 2017
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The aim of the study was to examine aged air masses being transported from the European continent towards Cyprus. Longer-lived oxygenated volatile organic compounds (OVOCs) such as methanol were mainly impacted by long-distance transport and showed higher values in air masses from eastern Europe than in a flow regime from the west. The impact of the transport through the marine boundary layer as well as the influence of the residual layer/free troposphere on OVOCs were studied.
Stephan Keßel, David Cabrera-Perez, Abraham Horowitz, Patrick R. Veres, Rolf Sander, Domenico Taraborrelli, Maria Tucceri, John N. Crowley, Andrea Pozzer, Christof Stönner, Luc Vereecken, Jos Lelieveld, and Jonathan Williams
Atmos. Chem. Phys., 17, 8789–8804, https://doi.org/10.5194/acp-17-8789-2017, https://doi.org/10.5194/acp-17-8789-2017, 2017
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In this study we identify an often overlooked stable oxide of carbon, namely carbon suboxide (C3O2), in ambient air. We have made C3O2 and in the laboratory determined its absorption cross section data and the rate of reaction with two important atmospheric oxidants, OH and O3. By incorporating known sources and sinks in a global model we have generated a first global picture of the distribution of this species in the atmosphere.
Anna Novelli, Korbinian Hens, Cheryl Tatum Ernest, Monica Martinez, Anke C. Nölscher, Vinayak Sinha, Pauli Paasonen, Tuukka Petäjä, Mikko Sipilä, Thomas Elste, Christian Plass-Dülmer, Gavin J. Phillips, Dagmar Kubistin, Jonathan Williams, Luc Vereecken, Jos Lelieveld, and Hartwig Harder
Atmos. Chem. Phys., 17, 7807–7826, https://doi.org/10.5194/acp-17-7807-2017, https://doi.org/10.5194/acp-17-7807-2017, 2017
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The ambient concentration of stabilised Criegee intermediates (SCIs) was estimated for two
environments using field data. The low concentrations predicted indicate that SCIs are
unlikely to have a large impact on atmospheric chemistry. Concurrent measurements of an OH background signal using the Mainz IPI-LIF-FAGE instrument were found to be consistent with the chemistry of SCIs during the measurement campaigns.
Alexandra P. Tsimpidi, Vlassis A. Karydis, Spyros N. Pandis, and Jos Lelieveld
Atmos. Chem. Phys., 17, 7345–7364, https://doi.org/10.5194/acp-17-7345-2017, https://doi.org/10.5194/acp-17-7345-2017, 2017
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We analyzed the sensitivity of model-predicted global-scale OA to parameters and assumptions that control primary emissions, photochemical aging, and the scavenging efficiency of LVOCs, SVOCs, and IVOCs. The simulated OA concentrations were evaluated against a global dataset of AMS measurements. According to our analysis, a combination of increased IVOCs and decreased hygroscopicity of the freshly emitted IVOCs can help reduce discrepancies between simulated SOA and observed OOA concentrations.
Narendra Ojha, Andrea Pozzer, Dimitris Akritidis, and Jos Lelieveld
Atmos. Chem. Phys., 17, 6743–6757, https://doi.org/10.5194/acp-17-6743-2017, https://doi.org/10.5194/acp-17-6743-2017, 2017
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We investigate the processes, frequency of occurrence and seasonality, and effects of strongly enhanced ozone layers in the middle–upper troposphere (SOPs) over the Himalayas using a global model (EMAC). Rapid transport of stratospheric air masses is found as a key underlying process. Model predicts more frequent SOP events during the pre-monsoon. SOPs are found to significantly enhance the tropospheric ozone column over the Himalayas.
Vlassis A. Karydis, Alexandra P. Tsimpidi, Sara Bacer, Andrea Pozzer, Athanasios Nenes, and Jos Lelieveld
Atmos. Chem. Phys., 17, 5601–5621, https://doi.org/10.5194/acp-17-5601-2017, https://doi.org/10.5194/acp-17-5601-2017, 2017
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The importance of mineral dust for cloud droplet formation is studied by considering the adsorption activation of insoluble dust particles and the thermodynamic interactions between mineral cations and inorganic anions. This study demonstrates that a comprehensive treatment of the CCN activity of mineral dust and its chemical and thermodynamic interactions with inorganic species by chemistry climate models is important to realistically account for aerosol–chemistry–cloud–climate interaction.
Jonathan M. Liebmann, Gerhard Schuster, Jan B. Schuladen, Nicolas Sobanski, Jos Lelieveld, and John N. Crowley
Atmos. Meas. Tech., 10, 1241–1258, https://doi.org/10.5194/amt-10-1241-2017, https://doi.org/10.5194/amt-10-1241-2017, 2017
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We describe the first instrument for measurement of the rate constant for reactive loss (i.e. the total reactivity) of NO3 in ambient air. This is essentially a measureement of the lifetime of NO3 and will help assess the role of NO3 and N2O5 in conversion of reactive nitrogen oxides to reservoir species in the troposphere.
Nicolas Sobanski, Jim Thieser, Jan Schuladen, Carina Sauvage, Wei Song, Jonathan Williams, Jos Lelieveld, and John N. Crowley
Atmos. Chem. Phys., 17, 4115–4130, https://doi.org/10.5194/acp-17-4115-2017, https://doi.org/10.5194/acp-17-4115-2017, 2017
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We investigated the formation of gas-phase organic nitrates at a forested semi-urban site. This work constitutes the first detailed analysis of the sum of organic nitrate mixing ratios measured by thermal dissociation cavity ring-down spectroscopy in continental Europe. Day (OH-initiated) and night-time (NO3-initiated) production of alkyl nitrates proceed at similar rates.
Mohamed Abdelkader, Swen Metzger, Benedikt Steil, Klaus Klingmüller, Holger Tost, Andrea Pozzer, Georgiy Stenchikov, Leonard Barrie, and Jos Lelieveld
Atmos. Chem. Phys., 17, 3799–3821, https://doi.org/10.5194/acp-17-3799-2017, https://doi.org/10.5194/acp-17-3799-2017, 2017
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We present a modeling study on the impacts of the key processes (dust emission flux, convection and dust aging parameterizations) that control the transatlantic dust transport using an advanced version of the EMAC atmospheric chemistry general circulation model. We define the
direct effect of dust agingas an increase in the AOD as a result of hygroscopic growth. We define the
indirect effectas a reduction in the dust AOD due to the higher removal of the aged dust particles.
Holger Tost
Atmos. Chem. Phys., 17, 1125–1142, https://doi.org/10.5194/acp-17-1125-2017, https://doi.org/10.5194/acp-17-1125-2017, 2017
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The paper describes the impact of lightning and the associated NOx emissions on upper-tropospheric aerosol nitrate. The consequences for both the chemical composition of the atmosphere as well as climatic impacts, which originate from lightning and modified aerosol particles, are analysed and discussed.
Sinikka T. Lennartz, Christa A. Marandino, Marc von Hobe, Pau Cortes, Birgit Quack, Rafel Simo, Dennis Booge, Andrea Pozzer, Tobias Steinhoff, Damian L. Arevalo-Martinez, Corinna Kloss, Astrid Bracher, Rüdiger Röttgers, Elliot Atlas, and Kirstin Krüger
Atmos. Chem. Phys., 17, 385–402, https://doi.org/10.5194/acp-17-385-2017, https://doi.org/10.5194/acp-17-385-2017, 2017
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We present new sea surface and marine boundary layer measurements of carbonyl sulfide, the most abundant sulfur gas in the atmosphere, and calculate an oceanic emission estimate. Our results imply that oceanic emissions are very unlikely to account for the missing source in the atmospheric budget that is currently discussed for OCS.
Imran A. Girach, Narendra Ojha, Prabha R. Nair, Andrea Pozzer, Yogesh K. Tiwari, K. Ravi Kumar, and Jos Lelieveld
Atmos. Chem. Phys., 17, 257–275, https://doi.org/10.5194/acp-17-257-2017, https://doi.org/10.5194/acp-17-257-2017, 2017
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This study presents first ship-borne measurements of trace gases over the Bay of Bengal during summer monsoon. The observed variations in trace gases are shown to be due to dynamics/transport and en route photochemistry. Analysis of meteorological and chemical fields shows that significantly lower ozone during rainfall is associated with the downdrafts. A regional model reproduces the observed variations and revealed the rapid transport of ozone across the Bay of Bengal during an event.
Sara Bacer, Theodoros Christoudias, and Andrea Pozzer
Atmos. Chem. Phys., 16, 15581–15592, https://doi.org/10.5194/acp-16-15581-2016, https://doi.org/10.5194/acp-16-15581-2016, 2016
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We investigate the influence of the North Atlantic Oscillation on atmospheric pollutant transport in the 21st century under a global climate-change scenario, using a coupled atmosphere–chemistry–ocean general circulation model. We find that, at the end of the century, the south-western Mediterranean and northern Africa will see higher pollutant concentrations during positive NAO phases with respect to the past, while a wider part of north Europe will see lower pollutant concentrations.
Hannah Meusel, Uwe Kuhn, Andreas Reiffs, Chinmay Mallik, Hartwig Harder, Monica Martinez, Jan Schuladen, Birger Bohn, Uwe Parchatka, John N. Crowley, Horst Fischer, Laura Tomsche, Anna Novelli, Thorsten Hoffmann, Ruud H. H. Janssen, Oscar Hartogensis, Michael Pikridas, Mihalis Vrekoussis, Efstratios Bourtsoukidis, Bettina Weber, Jos Lelieveld, Jonathan Williams, Ulrich Pöschl, Yafang Cheng, and Hang Su
Atmos. Chem. Phys., 16, 14475–14493, https://doi.org/10.5194/acp-16-14475-2016, https://doi.org/10.5194/acp-16-14475-2016, 2016
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There are many studies which show discrepancies between modeled and measured nitrous acid (HONO, precursor of OH radical) in the troposphere but with no satisfactory explanation. Ideal conditions to study the unknown sources of HONO were found on Cyprus, a remote Mediterranean island. Budget analysis of trace gas measurements indicates a common source of NO and HONO, which is not related to anthropogenic activity and is most likely derived from biologic activity in soils and subsequent emission.
Dimitris Akritidis, Andrea Pozzer, Prodromos Zanis, Evangelos Tyrlis, Bojan Škerlak, Michael Sprenger, and Jos Lelieveld
Atmos. Chem. Phys., 16, 14025–14039, https://doi.org/10.5194/acp-16-14025-2016, https://doi.org/10.5194/acp-16-14025-2016, 2016
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We investigate the contribution of tropopause folds in the summertime tropospheric ozone pool over the eastern Mediterranean and the Middle East. For this purpose we use the EMAC atmospheric chemistry–climate model and a fold identification algorithm. A clear increase of ozone is found in the middle troposphere due to fold activity. The interannual variability of near-surface ozone over the eastern Mediterranean is related to that of both tropopause folds and ozone in the free troposphere.
Aristeidis K. Georgoulias, Georgia Alexandri, Konstantinos A. Kourtidis, Jos Lelieveld, Prodromos Zanis, Ulrich Pöschl, Robert Levy, Vassilis Amiridis, Eleni Marinou, and Athanasios Tsikerdekis
Atmos. Chem. Phys., 16, 13853–13884, https://doi.org/10.5194/acp-16-13853-2016, https://doi.org/10.5194/acp-16-13853-2016, 2016
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In this work, single pixel observations from MODIS Terra and Aqua are analyzed together with data from other satellite sensors, reanalysis projects and a chemistry–aerosol-transport model to study the spatiotemporal variability of different aerosol types. The results are in accordance with previous works and are a good reference for future studies in the area focusing on aerosols, clouds, radiation and the effects of particle pollution on human health.
Gavin J. Phillips, Jim Thieser, Mingjin Tang, Nicolas Sobanski, Gerhard Schuster, Johannes Fachinger, Frank Drewnick, Stephan Borrmann, Heinz Bingemer, Jos Lelieveld, and John N. Crowley
Atmos. Chem. Phys., 16, 13231–13249, https://doi.org/10.5194/acp-16-13231-2016, https://doi.org/10.5194/acp-16-13231-2016, 2016
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We use trace gas measurements (N2O5, ClNO2, NO3) and particle properties (surface area, nitrate content etc.) to derive uptake coefficients (the probability of removal from the gas-phase on a per-collision basis) for the interaction of N2O5 with ambient aerosol and also the efficiency of formation of ClNO2. The uptake coefficients show high variability but are reasonably well captured by parameterisations based on laboratory measurements.
Kathleen A. Mar, Narendra Ojha, Andrea Pozzer, and Tim M. Butler
Geosci. Model Dev., 9, 3699–3728, https://doi.org/10.5194/gmd-9-3699-2016, https://doi.org/10.5194/gmd-9-3699-2016, 2016
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Ground-level ozone is an air pollutant with adverse effects on human and ecosystem health and is also a climate forcer with a significant warming effect. This paper presents the setup and evaluation of a model for ozone air quality over Europe. Within the model evaluation, we compare the use of two commonly used photochemical schemes, and we conclude that uncertainties in the representation of chemistry are important to consider when using air quality models for policy applications.
Nicolas Sobanski, Jan Schuladen, Gerhard Schuster, Jos Lelieveld, and John N. Crowley
Atmos. Meas. Tech., 9, 5103–5118, https://doi.org/10.5194/amt-9-5103-2016, https://doi.org/10.5194/amt-9-5103-2016, 2016
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We report the characteristics and performances of a cavity ring-down spectrometer (CRDS) designed for field measurements that uses light absorption at 662 and 405 nm to detect different reactive nitrogen species or group of species in the gas phase, either directly or after thermal decomposition. We report improvements compared to currently existing instruments, and describe the corrections applied to the raw data to account for chemical and optical interferences.
Jos Lelieveld, Sergey Gromov, Andrea Pozzer, and Domenico Taraborrelli
Atmos. Chem. Phys., 16, 12477–12493, https://doi.org/10.5194/acp-16-12477-2016, https://doi.org/10.5194/acp-16-12477-2016, 2016
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The self-cleaning capacity of the atmosphere is controlled by hydroxyl (OH) radicals in the troposphere. There are primary and secondary OH sources, the former through the photodissociation of ozone, the latter through OH recycling. We used a global model, showing that secondary sources are larger than assumed previously, which buffers OH. Complementary OH formation mechanisms in pristine and polluted environments, connected through transport of ozone, can maintain stable global OH levels.
Mariano Mertens, Astrid Kerkweg, Patrick Jöckel, Holger Tost, and Christiane Hofmann
Geosci. Model Dev., 9, 3545–3567, https://doi.org/10.5194/gmd-9-3545-2016, https://doi.org/10.5194/gmd-9-3545-2016, 2016
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This fourth part in a series of publications describing the newly developed regional chemistry–climate system MECO(n) is dedicated to the evaluation of MECO(n) with respect to tropospheric gas-phase chemistry. For this, a simulation incorporating two regional instances, one over Europe with 50 km resolution and one over Germany with 12 km resolution, is conducted. The model results are compared with satellite, ground-based and aircraft in situ observations.
Narendra Singh, Raman Solanki, Narendra Ojha, Ruud H. H. Janssen, Andrea Pozzer, and Surendra K. Dhaka
Atmos. Chem. Phys., 16, 10559–10572, https://doi.org/10.5194/acp-16-10559-2016, https://doi.org/10.5194/acp-16-10559-2016, 2016
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Our study presents measurements and model simulations of boundary layer evolution over a mountain peak in the central Himalayas. The observations were made as a part of the Ganges Valley Aerosol Experiment. The implications of biases in model simulated boundary layer towards simulations of trace species is investigated.
Alexandra P. Tsimpidi, Vlassis A. Karydis, Spyros N. Pandis, and Jos Lelieveld
Atmos. Chem. Phys., 16, 8939–8962, https://doi.org/10.5194/acp-16-8939-2016, https://doi.org/10.5194/acp-16-8939-2016, 2016
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In this work we use a global chemistry climate model together with a comprehensive global AMS data set in order to provide valuable insights into the temporal and geographical variability of the contribution of the emitted particles and the chemically processed organic material from combustion sources to total OA. This study reveals the high importance of SOA from anthropogenic sources on global OA concentrations and identifies plausible sources of discrepancy between models and measurements.
Steffen Beirle, Christoph Hörmann, Patrick Jöckel, Song Liu, Marloes Penning de Vries, Andrea Pozzer, Holger Sihler, Pieter Valks, and Thomas Wagner
Atmos. Meas. Tech., 9, 2753–2779, https://doi.org/10.5194/amt-9-2753-2016, https://doi.org/10.5194/amt-9-2753-2016, 2016
Simone Dietmüller, Patrick Jöckel, Holger Tost, Markus Kunze, Catrin Gellhorn, Sabine Brinkop, Christine Frömming, Michael Ponater, Benedikt Steil, Axel Lauer, and Johannes Hendricks
Geosci. Model Dev., 9, 2209–2222, https://doi.org/10.5194/gmd-9-2209-2016, https://doi.org/10.5194/gmd-9-2209-2016, 2016
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Four new radiation related submodels (RAD, AEROPT, CLOUDOPT, and ORBIT) are available within the MESSy framework now. They are largely based on the original radiation scheme of ECHAM5. RAD simulates radiative transfer, AEROPT calculates aerosol optical properties, CLOUDOPT calculates cloud optical properties, and ORBIT is responsible for Earth orbit calculations. Multiple diagnostic calls of the radiation routine are possible, so radiative forcing can be calculated during the model simulation.
Swen Metzger, Benedikt Steil, Mohamed Abdelkader, Klaus Klingmüller, Li Xu, Joyce E. Penner, Christos Fountoukis, Athanasios Nenes, and Jos Lelieveld
Atmos. Chem. Phys., 16, 7213–7237, https://doi.org/10.5194/acp-16-7213-2016, https://doi.org/10.5194/acp-16-7213-2016, 2016
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We introduce an unique single parameter framework to efficiently parameterize the aerosol water uptake for mixtures of semi-volatile and non-volatile compounds, being entirely based on the single solute specific coefficient introduced in Metzger et al. (2012).
David Cabrera-Perez, Domenico Taraborrelli, Rolf Sander, and Andrea Pozzer
Atmos. Chem. Phys., 16, 6931–6947, https://doi.org/10.5194/acp-16-6931-2016, https://doi.org/10.5194/acp-16-6931-2016, 2016
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The global atmospheric budget and distribution of monocyclic aromatic compounds is estimated, using an atmospheric chemistry general circulation model. Simulation results are evaluated with observations with the goal of understanding emission, production and removal of these compounds. Anthropogenic and biomass burning are the main sources of aromatic compounds to the atmosphere. The main sink is photochemical decomposition and in lesser importance dry deposition.
Klaus Klingmüller, Andrea Pozzer, Swen Metzger, Georgiy L. Stenchikov, and Jos Lelieveld
Atmos. Chem. Phys., 16, 5063–5073, https://doi.org/10.5194/acp-16-5063-2016, https://doi.org/10.5194/acp-16-5063-2016, 2016
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During the last decade, the Middle East experienced the strongest increase in atmospheric aerosol concentrations worldwide. Based on satellite observations, the present study corroborates this trend and reveals correlations with soil moisture and precipitation in and surrounding the Fertile Crescent. This suggests that the increasing drought conditions in this region have enhanced dust emissions, a tendency which is expected to be intensified by climate change.
N. Sobanski, M. J. Tang, J. Thieser, G. Schuster, D. Pöhler, H. Fischer, W. Song, C. Sauvage, J. Williams, J. Fachinger, F. Berkes, P. Hoor, U. Platt, J. Lelieveld, and J. N. Crowley
Atmos. Chem. Phys., 16, 4867–4883, https://doi.org/10.5194/acp-16-4867-2016, https://doi.org/10.5194/acp-16-4867-2016, 2016
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The nitrate radical (NO3) is an important nocturnal oxidant. By measuring NO3, its precursors (nitrogen dioxide and ozone) and several trace gases with which it reacts, we examined the chemical and meteorological factors influencing the lifetime of NO3 at a semi-rural mountain site. Unexpectedly long lifetimes, approaching 1 h, were observed on several nights and were associated with a low-lying residual layer. We discuss the role of other reactions that convert NO2 to NO3.
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.
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.
N. I. Kristiansen, A. Stohl, D. J. L. Olivié, B. Croft, O. A. Søvde, H. Klein, T. Christoudias, D. Kunkel, S. J. Leadbetter, Y. H. Lee, K. Zhang, K. Tsigaridis, T. Bergman, N. Evangeliou, H. Wang, P.-L. Ma, R. C. Easter, P. J. Rasch, X. Liu, G. Pitari, G. Di Genova, S. Y. Zhao, Y. Balkanski, S. E. Bauer, G. S. Faluvegi, H. Kokkola, R. V. Martin, J. R. Pierce, M. Schulz, D. Shindell, H. Tost, and H. Zhang
Atmos. Chem. Phys., 16, 3525–3561, https://doi.org/10.5194/acp-16-3525-2016, https://doi.org/10.5194/acp-16-3525-2016, 2016
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Processes affecting aerosol removal from the atmosphere are not fully understood. In this study we investigate to what extent atmospheric transport models can reproduce observed loss of aerosols. We compare measurements of radioactive isotopes, that attached to ambient sulfate aerosols during the 2011 Fukushima nuclear accident, to 19 models using identical emissions. Results indicate aerosol removal that is too fast in most models, and apply to aerosols that have undergone long-range transport.
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.
J. Thieser, G. Schuster, J. Schuladen, G. J. Phillips, A. Reiffs, U. Parchatka, D. Pöhler, J. Lelieveld, and J. N. Crowley
Atmos. Meas. Tech., 9, 553–576, https://doi.org/10.5194/amt-9-553-2016, https://doi.org/10.5194/amt-9-553-2016, 2016
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We report on the use of thermal dissociation cavity ring-down spectroscopy to detect NO2, peroxy nitrates and alkyl nitrates. We present both laboratory studies that characterise the chemical formation and loss of NO2 in the heated inlets and also result from a first field deployment.
V. A. Karydis, A. P. Tsimpidi, A. Pozzer, M. Astitha, and J. Lelieveld
Atmos. Chem. Phys., 16, 1491–1509, https://doi.org/10.5194/acp-16-1491-2016, https://doi.org/10.5194/acp-16-1491-2016, 2016
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We provide an assessment of the chemical composition and global aerosol load of aerosol nitrate and determine the effect of mineral dust on its formation due to thermodynamical interactions. For this purpose we used an explicit geographical representation of the emitted soil particle size distribution and chemical composition. We conclude mineral dust aerosol chemistry is important for nitrate aerosol formation and significantly affects its global distribution, especially in the coarse mode.
A. J. G. Baumgaertner, P. Jöckel, A. Kerkweg, R. Sander, and H. Tost
Geosci. Model Dev., 9, 125–135, https://doi.org/10.5194/gmd-9-125-2016, https://doi.org/10.5194/gmd-9-125-2016, 2016
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The Community Earth System Model (CESM1) is connected to the the Modular Earth Submodel System (MESSy) as a new base model. This allows MESSy users the option to utilize either the state-of-the art spectral element atmosphere dynamical core or the finite volume core of CESM1. Additionally, this makes several other component models available to MESSy users.
S. Bacer, T. Christoudias, and A. Pozzer
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acpd-15-33049-2015, https://doi.org/10.5194/acpd-15-33049-2015, 2015
Preprint withdrawn
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We investigate the temporal variability of the North Atlantic Oscillation (NAO) pattern and its relation to the atmospheric dispersion of pollutants in the near past and in the future.
We use a global climate circulation model in order to analyze the NAO signal and its correlation with pollutant concentrations. We find that the NAO is influenced by natural climate variability and that the NAO Indices may be used as indicators of (future) pollutant transport over Europe.
M. Abdelkader, S. Metzger, R. E. Mamouri, M. Astitha, L. Barrie, Z. Levin, and J. Lelieveld
Atmos. Chem. Phys., 15, 9173–9189, https://doi.org/10.5194/acp-15-9173-2015, https://doi.org/10.5194/acp-15-9173-2015, 2015
H. G. Ouwersloot, A. Pozzer, B. Steil, H. Tost, and J. Lelieveld
Geosci. Model Dev., 8, 2435–2445, https://doi.org/10.5194/gmd-8-2435-2015, https://doi.org/10.5194/gmd-8-2435-2015, 2015
H. Fischer, A. Pozzer, T. Schmitt, P. Jöckel, T. Klippel, D. Taraborrelli, and J. Lelieveld
Atmos. Chem. Phys., 15, 6971–6980, https://doi.org/10.5194/acp-15-6971-2015, https://doi.org/10.5194/acp-15-6971-2015, 2015
S. Zheng, A. Pozzer, C. X. Cao, and J. Lelieveld
Atmos. Chem. Phys., 15, 5715–5725, https://doi.org/10.5194/acp-15-5715-2015, https://doi.org/10.5194/acp-15-5715-2015, 2015
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The present study uses aerosol optical depth as proxy to estimate 12 years of PM2.5 data for the Beijing central area and calculate the yearly premature mortality by different diseases attributable to PM2.5. The estimated average total mortality due to PM2.5 is about 5100 individuals/year for the period 2001--2012 in the Beijing central area, and the per capita mortality for all ages due to PM2.5 is around 15 per 10,000 person-years for the period 2010--2012.
A. Pozzer, A. de Meij, J. Yoon, H. Tost, A. K. Georgoulias, and M. Astitha
Atmos. Chem. Phys., 15, 5521–5535, https://doi.org/10.5194/acp-15-5521-2015, https://doi.org/10.5194/acp-15-5521-2015, 2015
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Thanks to numerical simulations and satellite observations, it is shown that aerosol optical depth (AOD) trends (2000--2010 period) over the US and Europe are due to emission decrease, while over the Sahara Desert and the Middle East they are due to meteorological changes. Over Southeast Asia, both meteorology and emission changes are important for the AOD trends.
It is shown that soluble components strongly influence AOD, as their contribution is enhanced by the aerosol water content.
R. H. H. Janssen and A. Pozzer
Geosci. Model Dev., 8, 453–471, https://doi.org/10.5194/gmd-8-453-2015, https://doi.org/10.5194/gmd-8-453-2015, 2015
A. P. Tsimpidi, V. A. Karydis, A. Pozzer, S. N. Pandis, and J. Lelieveld
Geosci. Model Dev., 7, 3153–3172, https://doi.org/10.5194/gmd-7-3153-2014, https://doi.org/10.5194/gmd-7-3153-2014, 2014
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A computationally efficient module for the description of OA composition and evolution in the atmosphere has been developed. This module subdivides OA into several compounds based on their source of origin and volatility, allowing the quantification of POA vs. SOA as well as biogenic vs. anthropogenic contributions to OA concentrations. Such fundamental information can shed light on long-term changes in OA abundance, and hence project the effects of OA on future air quality and climate.
R. Sander, P. Jöckel, O. Kirner, A. T. Kunert, J. Landgraf, and A. Pozzer
Geosci. Model Dev., 7, 2653–2662, https://doi.org/10.5194/gmd-7-2653-2014, https://doi.org/10.5194/gmd-7-2653-2014, 2014
K. Klingmüller, B. Steil, C. Brühl, H. Tost, and J. Lelieveld
Geosci. Model Dev., 7, 2503–2516, https://doi.org/10.5194/gmd-7-2503-2014, https://doi.org/10.5194/gmd-7-2503-2014, 2014
A. Novelli, K. Hens, C. Tatum Ernest, D. Kubistin, E. Regelin, T. Elste, C. Plass-Dülmer, M. Martinez, J. Lelieveld, and H. Harder
Atmos. Meas. Tech., 7, 3413–3430, https://doi.org/10.5194/amt-7-3413-2014, https://doi.org/10.5194/amt-7-3413-2014, 2014
J. Yoon and A. Pozzer
Atmos. Chem. Phys., 14, 10465–10482, https://doi.org/10.5194/acp-14-10465-2014, https://doi.org/10.5194/acp-14-10465-2014, 2014
H. Bozem, H. Fischer, C. Gurk, C. L. Schiller, U. Parchatka, R. Koenigstedt, A. Stickler, M. Martinez, H. Harder, D. Kubistin, J. Williams, G. Eerdekens, and J. Lelieveld
Atmos. Chem. Phys., 14, 8917–8931, https://doi.org/10.5194/acp-14-8917-2014, https://doi.org/10.5194/acp-14-8917-2014, 2014
D. Y. Chang, H. Tost, B. Steil, and J. Lelieveld
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acpd-14-21975-2014, https://doi.org/10.5194/acpd-14-21975-2014, 2014
Preprint withdrawn
K. Hens, A. Novelli, M. Martinez, J. Auld, R. Axinte, B. Bohn, H. Fischer, P. Keronen, D. Kubistin, A. C. Nölscher, R. Oswald, P. Paasonen, T. Petäjä, E. Regelin, R. Sander, V. Sinha, M. Sipilä, D. Taraborrelli, C. Tatum Ernest, J. Williams, J. Lelieveld, and H. Harder
Atmos. Chem. Phys., 14, 8723–8747, https://doi.org/10.5194/acp-14-8723-2014, https://doi.org/10.5194/acp-14-8723-2014, 2014
A. K. Mishra, K. Klingmueller, E. Fredj, J. Lelieveld, Y. Rudich, and I. Koren
Atmos. Chem. Phys., 14, 7213–7231, https://doi.org/10.5194/acp-14-7213-2014, https://doi.org/10.5194/acp-14-7213-2014, 2014
H. Rybka and H. Tost
Atmos. Chem. Phys., 14, 5561–5576, https://doi.org/10.5194/acp-14-5561-2014, https://doi.org/10.5194/acp-14-5561-2014, 2014
T. Christoudias, Y. Proestos, and J. Lelieveld
Atmos. Chem. Phys., 14, 4607–4616, https://doi.org/10.5194/acp-14-4607-2014, https://doi.org/10.5194/acp-14-4607-2014, 2014
G. W. Mann, K. S. Carslaw, C. L. Reddington, K. J. Pringle, M. Schulz, A. Asmi, D. V. Spracklen, D. A. Ridley, M. T. Woodhouse, L. A. Lee, K. Zhang, S. J. Ghan, R. C. Easter, X. Liu, P. Stier, Y. H. Lee, P. J. Adams, H. Tost, J. Lelieveld, S. E. Bauer, K. Tsigaridis, T. P. C. van Noije, A. Strunk, E. Vignati, N. Bellouin, M. Dalvi, C. E. Johnson, T. Bergman, H. Kokkola, K. von Salzen, F. Yu, G. Luo, A. Petzold, J. Heintzenberg, A. Clarke, J. A. Ogren, J. Gras, U. Baltensperger, U. Kaminski, S. G. Jennings, C. D. O'Dowd, R. M. Harrison, D. C. S. Beddows, M. Kulmala, Y. Viisanen, V. Ulevicius, N. Mihalopoulos, V. Zdimal, M. Fiebig, H.-C. Hansson, E. Swietlicki, and J. S. Henzing
Atmos. Chem. Phys., 14, 4679–4713, https://doi.org/10.5194/acp-14-4679-2014, https://doi.org/10.5194/acp-14-4679-2014, 2014
J. A. Adame, M. Martínez, M. Sorribas, P. J. Hidalgo, H. Harder, J.-M. Diesch, F. Drewnick, W. Song, J. Williams, V. Sinha, M. A. Hernández-Ceballos, J. Vilà-Guerau de Arellano, R. Sander, Z. Hosaynali-Beygi, H. Fischer, J. Lelieveld, and B. De la Morena
Atmos. Chem. Phys., 14, 2325–2342, https://doi.org/10.5194/acp-14-2325-2014, https://doi.org/10.5194/acp-14-2325-2014, 2014
C. Liu, S. Beirle, T. Butler, P. Hoor, C. Frankenberg, P. Jöckel, M. Penning de Vries, U. Platt, A. Pozzer, M. G. Lawrence, J. Lelieveld, H. Tost, and T. Wagner
Atmos. Chem. Phys., 14, 1717–1732, https://doi.org/10.5194/acp-14-1717-2014, https://doi.org/10.5194/acp-14-1717-2014, 2014
Y. F. Elshorbany, P. J. Crutzen, B. Steil, A. Pozzer, H. Tost, and J. Lelieveld
Atmos. Chem. Phys., 14, 1167–1184, https://doi.org/10.5194/acp-14-1167-2014, https://doi.org/10.5194/acp-14-1167-2014, 2014
D. Giannadaki, A. Pozzer, and J. Lelieveld
Atmos. Chem. Phys., 14, 957–968, https://doi.org/10.5194/acp-14-957-2014, https://doi.org/10.5194/acp-14-957-2014, 2014
P. Zanis, P. Hadjinicolaou, A. Pozzer, E. Tyrlis, S. Dafka, N. Mihalopoulos, and J. Lelieveld
Atmos. Chem. Phys., 14, 115–132, https://doi.org/10.5194/acp-14-115-2014, https://doi.org/10.5194/acp-14-115-2014, 2014
J. Yoon, A. Pozzer, P. Hoor, D. Y. Chang, S. Beirle, T. Wagner, S. Schloegl, J. Lelieveld, and H. M. Worden
Atmos. Chem. Phys., 13, 11307–11316, https://doi.org/10.5194/acp-13-11307-2013, https://doi.org/10.5194/acp-13-11307-2013, 2013
E. Regelin, H. Harder, M. Martinez, D. Kubistin, C. Tatum Ernest, H. Bozem, T. Klippel, Z. Hosaynali-Beygi, H. Fischer, R. Sander, P. Jöckel, R. Königstedt, and J. Lelieveld
Atmos. Chem. Phys., 13, 10703–10720, https://doi.org/10.5194/acp-13-10703-2013, https://doi.org/10.5194/acp-13-10703-2013, 2013
O. Sourdeval, L. C. -Labonnote, G. Brogniez, O. Jourdan, J. Pelon, and A. Garnier
Atmos. Chem. Phys., 13, 8229–8244, https://doi.org/10.5194/acp-13-8229-2013, https://doi.org/10.5194/acp-13-8229-2013, 2013
J. Lelieveld, C. Barlas, D. Giannadaki, and A. Pozzer
Atmos. Chem. Phys., 13, 7023–7037, https://doi.org/10.5194/acp-13-7023-2013, https://doi.org/10.5194/acp-13-7023-2013, 2013
A.C. Nölscher, E. Bourtsoukidis, B. Bonn, J. Kesselmeier, J. Lelieveld, and J. Williams
Biogeosciences, 10, 4241–4257, https://doi.org/10.5194/bg-10-4241-2013, https://doi.org/10.5194/bg-10-4241-2013, 2013
C. Brühl, J. Lelieveld, M. Höpfner, and H. Tost
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acpd-13-11395-2013, https://doi.org/10.5194/acpd-13-11395-2013, 2013
Revised manuscript not accepted
D. Kunkel, H. Tost, and M. G. Lawrence
Atmos. Chem. Phys., 13, 4203–4222, https://doi.org/10.5194/acp-13-4203-2013, https://doi.org/10.5194/acp-13-4203-2013, 2013
G. J. Phillips, N. Pouvesle, J. Thieser, G. Schuster, R. Axinte, H. Fischer, J. Williams, J. Lelieveld, and J. N. Crowley
Atmos. Chem. Phys., 13, 1129–1139, https://doi.org/10.5194/acp-13-1129-2013, https://doi.org/10.5194/acp-13-1129-2013, 2013
J. Lelieveld, M. G. Lawrence, and D. Kunkel
Atmos. Chem. Phys., 13, 31–34, https://doi.org/10.5194/acp-13-31-2013, https://doi.org/10.5194/acp-13-31-2013, 2013
A. Jugold, F. Althoff, M. Hurkuck, M. Greule, K. Lenhart, J. Lelieveld, and F. Keppler
Biogeosciences, 9, 5291–5301, https://doi.org/10.5194/bg-9-5291-2012, https://doi.org/10.5194/bg-9-5291-2012, 2012
Related subject area
Subject: Clouds and Precipitation | Research Activity: Atmospheric Modelling | Altitude Range: Troposphere | Science Focus: Physics (physical properties and processes)
Southern Ocean cloud and shortwave radiation biases in a nudged climate model simulation: does the model ever get it right?
Aerosol characteristics and polarimetric signatures for a deep convective storm over the northwestern part of Europe – modeling and observations
Evaluation of tropical water vapour from CMIP6 global climate models using the ESA CCI Water Vapour climate data records
Aerosol–stratocumulus interactions: towards a better process understanding using closures between observations and large eddy simulations
The impacts of secondary ice production on microphysics and dynamics in tropical convection
Cloud adjustments from large-scale smoke–circulation interactions strongly modulate the southeastern Atlantic stratocumulus-to-cumulus transition
The influence of multiple groups of biological ice nucleating particles on microphysical properties of mixed-phase clouds observed during MC3E
Quantifying vertical wind shear effects in shallow cumulus clouds over Amazonia
Cirrus cloud thinning using a more physically based ice microphysics scheme in the ECHAM-HAM general circulation model
Long–term upper–troposphere climatology of potential contrail occurrence over the Paris area derived from radiosonde observations
Impacts of combined microphysical and land-surface uncertainties on convective clouds and precipitation in different weather regimes
Equilibrium climate sensitivity increases with aerosol concentration due to changes in rain efficiency
Weakening of tropical sea breeze convective systems through interactions of aerosol, radiation, and soil moisture
Sensitivity analysis of an aerosol-aware microphysics scheme in Weather Research and Forecasting (WRF) during case studies of fog in Namibia
Do Arctic mixed-phase clouds sometimes dissipate due to insufficient aerosol? Evidence from comparisons between observations and idealized simulations
Contrail formation within cirrus: ICON-LEM simulations of the impact of cirrus cloud properties on contrail formation
Impact of Holuhraun volcano aerosols on clouds in cloud-system-resolving simulations
Warm and moist air intrusions into the winter Arctic: a Lagrangian view on the near-surface energy budgets
Convective updrafts near sea-breeze fronts
Evaluation of modelled summertime convective storms using polarimetric radar observations
Evaluating seasonal and regional distribution of snowfall in regional climate model simulations in the Arctic
Modeling impacts of ice-nucleating particles from marine aerosols on mixed-phase orographic clouds during 2015 ACAPEX field campaign
Influences of an entrainment–mixing parameterization on numerical simulations of cumulus and stratocumulus clouds
Investigation of ice cloud modeling capabilities for the irregularly shaped Voronoi ice scattering models in climate simulations
Assessing the potential for simplification in global climate model cloud microphysics
Technical note: Parameterising cloud base updraft velocity of marine stratocumuli
Radiative and microphysical responses of clouds to an anomalous increase in fire particles over the Maritime Continent in 2015
Intricate relations among particle collision, relative motion and clustering in turbulent clouds: computational observation and theory
The effect of marine ice-nucleating particles on mixed-phase clouds
A strong statistical link between aerosol indirect effects and the self-similarity of rainfall distributions
Quantifying albedo susceptibility biases in shallow clouds
Machine learning of cloud types shows higher climate sensitivity is associated with lower cloud biases
Primary and secondary ice production: interactions and their relative importance
Microphysical processes producing high ice water contents (HIWCs) in tropical convective clouds during the HAIC-HIWC field campaign: dominant role of secondary ice production
Importance of aerosols and shape of the cloud droplet size distribution for convective clouds and precipitation
Secondary ice production processes in wintertime alpine mixed-phase clouds
Multi-thermals and high concentrations of secondary ice: a modelling study of convective clouds during the Ice in Clouds Experiment – Dust (ICE-D) campaign
Subgrid-scale horizontal and vertical variation of cloud water in stratocumulus clouds: a case study based on LES and comparisons with in situ observations
A vertical transport window of water vapor in the troposphere over the Tibetan Plateau with implications for global climate change
Box model trajectory studies of contrail formation using a particle-based cloud microphysics scheme
Updraft dynamics and microphysics: on the added value of the cumulus thermal reference frame in simulations of aerosol–deep convection interactions
Demistify: a large-eddy simulation (LES) and single-column model (SCM) intercomparison of radiation fog
Case study of a moisture intrusion over the Arctic with the ICOsahedral Non-hydrostatic (ICON) model: resolution dependence of its representation
New investigations on homogeneous ice nucleation: the effects of water activity and water saturation formulations
Cloud droplet formation at the base of tropical convective clouds: closure between modeling and measurement results of ACRIDICON–CHUVA
Impacts of long-range-transported mineral dust on summertime convective cloud and precipitation: a case study over the Taiwan region
Model emulation to understand the joint effects of ice-nucleating particles and secondary ice production on deep convective anvil cirrus
Improving the representation of aggregation in a two-moment microphysical scheme with statistics of multi-frequency Doppler radar observations
Overview towards improved understanding of the mechanisms leading to heavy precipitation in the western Mediterranean: lessons learned from HyMeX
Midlatitude mixed-phase stratocumulus clouds and their interactions with aerosols: how ice processes affect microphysical, dynamic, and thermodynamic development in those clouds and interactions?
Sonya L. Fiddes, Alain Protat, Marc D. Mallet, Simon P. Alexander, and Matthew T. Woodhouse
Atmos. Chem. Phys., 22, 14603–14630, https://doi.org/10.5194/acp-22-14603-2022, https://doi.org/10.5194/acp-22-14603-2022, 2022
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Climate models have difficulty simulating Southern Ocean clouds, impacting how much sunlight reaches the surface. We use machine learning to group different cloud types observed from satellites and simulated in a climate model. We find the model does a poor job of simulating the same cloud type as what the satellite shows and, even when it does, the cloud properties and amount of reflected sunlight are incorrect. We have a lot of work to do to model clouds correctly over the Southern Ocean.
Prabhakar Shrestha, Jana Mendrok, and Dominik Brunner
Atmos. Chem. Phys., 22, 14095–14117, https://doi.org/10.5194/acp-22-14095-2022, https://doi.org/10.5194/acp-22-14095-2022, 2022
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The study extends the Terrestrial Systems Modeling Platform with gas-phase chemistry aerosol dynamics and a radar forward operator to enable detailed studies of aerosol–cloud–precipitation interactions. This is demonstrated using a case study of a deep convective storm, which showed that the strong updraft in the convective core of the storm produced aerosol-tower-like features, which affected the size of the hydrometeors and the simulated polarimetric features (e.g., ZDR and KDP columns).
Jia He, Helene Brogniez, and Laurence Picon
Atmos. Chem. Phys., 22, 12591–12606, https://doi.org/10.5194/acp-22-12591-2022, https://doi.org/10.5194/acp-22-12591-2022, 2022
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A 2003–2017 satellite-based atmospheric water vapour climate data record is used to assess climate models and reanalyses. The focus is on the tropical belt, whose regional variations in the hydrological cycle are related to the tropospheric overturning circulation. While there are similarities in the interannual variability, the major discrepancies can be explained by the presence of clouds, the representation of moisture fluxes at the surface and cloud processes in the models.
Silvia M. Calderón, Juha Tonttila, Angela Buchholz, Jorma Joutsensaari, Mika Komppula, Ari Leskinen, Liqing Hao, Dmitri Moisseev, Iida Pullinen, Petri Tiitta, Jian Xu, Annele Virtanen, Harri Kokkola, and Sami Romakkaniemi
Atmos. Chem. Phys., 22, 12417–12441, https://doi.org/10.5194/acp-22-12417-2022, https://doi.org/10.5194/acp-22-12417-2022, 2022
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The spatial and temporal restrictions of observations and oversimplified aerosol representation in large eddy simulations (LES) limit our understanding of aerosol–stratocumulus interactions. In this closure study of in situ and remote sensing observations and outputs from UCLALES–SALSA, we have assessed the role of convective overturning and aerosol effects in two cloud events observed at the Puijo SMEAR IV station, Finland, a diurnal-high aerosol case and a nocturnal-low aerosol case.
Zhipeng Qu, Alexei Korolev, Jason A. Milbrandt, Ivan Heckman, Yongjie Huang, Greg M. McFarquhar, Hugh Morrison, Mengistu Wolde, and Cuong Nguyen
Atmos. Chem. Phys., 22, 12287–12310, https://doi.org/10.5194/acp-22-12287-2022, https://doi.org/10.5194/acp-22-12287-2022, 2022
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Secondary ice production (SIP) is an important physical phenomenon that results in an increase in the cloud ice particle concentration and can have a significant impact on the evolution of clouds. Here, idealized simulations of a tropical convective system were conducted. Agreement between the simulations and observations highlights the impacts of SIP on the maintenance of tropical convection in nature and the importance of including the modelling of SIP in numerical weather prediction models.
Michael S. Diamond, Pablo E. Saide, Paquita Zuidema, Andrew S. Ackerman, Sarah J. Doherty, Ann M. Fridlind, Hamish Gordon, Calvin Howes, Jan Kazil, Takanobu Yamaguchi, Jianhao Zhang, Graham Feingold, and Robert Wood
Atmos. Chem. Phys., 22, 12113–12151, https://doi.org/10.5194/acp-22-12113-2022, https://doi.org/10.5194/acp-22-12113-2022, 2022
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Smoke from southern Africa blankets the southeast Atlantic from June-October, overlying a major transition region between overcast and scattered clouds. The smoke affects Earth's radiation budget by absorbing sunlight and changing cloud properties. We investigate these effects in regional climate and large eddy simulation models based on international field campaigns. We find that large-scale circulation changes more strongly affect cloud transitions than smoke microphysical effects in our case.
Sachin Patade, Deepak Waman, Akash Deshmukh, Ashok Kumar Gupta, Arti Jadav, Vaughan T. J. Phillips, Aaron Bansemer, Jacob Carlin, and Alexander Ryzhkov
Atmos. Chem. Phys., 22, 12055–12075, https://doi.org/10.5194/acp-22-12055-2022, https://doi.org/10.5194/acp-22-12055-2022, 2022
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This modeling study focuses on the role of multiple groups of primary biological aerosol particles as ice nuclei on cloud properties and precipitation. This was done by implementing a more realistic scheme for biological ice nucleating particles in the aerosol–cloud model. Results show that biological ice nucleating particles have a limited role in altering the ice phase and precipitation in deep convective clouds.
Micael Amore Cecchini, Marco de Bruine, Jordi Vilà-Guerau de Arellano, and Paulo Artaxo
Atmos. Chem. Phys., 22, 11867–11888, https://doi.org/10.5194/acp-22-11867-2022, https://doi.org/10.5194/acp-22-11867-2022, 2022
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Shallow clouds (vertical extent up to 3 km height) are ubiquitous throughout the Amazon and are responsible for redistributing the solar heat and moisture vertically and horizontally. They are a key component of the water cycle because they can grow past the shallow phase to contribute significantly to the precipitation formation. However, they need favourable environmental conditions to grow. In this study, we analyse how changing wind patterns affect the development of such shallow clouds.
Colin Tully, David Neubauer, Nadja Omanovic, and Ulrike Lohmann
Atmos. Chem. Phys., 22, 11455–11484, https://doi.org/10.5194/acp-22-11455-2022, https://doi.org/10.5194/acp-22-11455-2022, 2022
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The proposed geoengineering method, cirrus cloud thinning, was evaluated using a more physically based microphysics scheme coupled to a more realistic approach for calculating ice cloud fractions in the ECHAM-HAM GCM. Sensitivity tests reveal that using the new ice cloud fraction approach and increasing the critical ice saturation ratio for ice nucleation on seeding particles reduces warming from overseeding. However, this geoengineering method is unlikely to be feasible on a global scale.
Kevin Wolf, Nicolas Bellouin, and Olivier Boucher
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2022-584, https://doi.org/10.5194/acp-2022-584, 2022
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Recent studies estimate the radiative impact of contrails to be similar or larger than that of emitted CO2. Hence, contrail mitigation might be an opportunity to reduce the climate effect of aviation. A radiosonde data-set is analyzed in terms of the vertical distribution of potential contrails, contrail mitigation by flight altitude changes, and linkages with the tropopause and the jet stream. The effect of prospective jet engine developments and alternative fuels is estimated.
Christian Barthlott, Amirmahdi Zarboo, Takumi Matsunobu, and Christian Keil
Atmos. Chem. Phys., 22, 10841–10860, https://doi.org/10.5194/acp-22-10841-2022, https://doi.org/10.5194/acp-22-10841-2022, 2022
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The relevance of microphysical and land-surface uncertainties for convective-scale predictability is evaluated with a combined-perturbation strategy in realistic convection-resolving simulations. We find a large ensemble spread which demonstrates that the uncertainties investigated here and, in particular, their collective effect are highly relevant for quantitative precipitation forecasting of summertime convection in central Europe.
Guy Dagan
EGUsphere, https://doi.org/10.5194/egusphere-2022-777, https://doi.org/10.5194/egusphere-2022-777, 2022
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Using idealized simulations we demonstrate that the ECS, i.e., the increase in surface temperature under equilibrium conditions due to doubling of the CO2 concentration, increases with the aerosol concentration. The ECS increase is explained by a faster increase in precipitation efficiency with warming under high aerosol concentrations, which more efficiently depletes the water from the cloud and thus is manifested as an increase in the cloud feedback parameter.
J. Minnie Park and Susan C. van den Heever
Atmos. Chem. Phys., 22, 10527–10549, https://doi.org/10.5194/acp-22-10527-2022, https://doi.org/10.5194/acp-22-10527-2022, 2022
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This study explores how increased aerosol particles impact tropical sea breeze cloud systems under different environments and how a range of environments modulate these cloud responses. Overall, sea breeze flows and clouds that develop therein become weaker due to interactions between aerosols, sunlight, and land surface. In addition, surface rainfall also decreases with more aerosol particles. Weakening of cloud and rain with more aerosols is found irrespective of 130 different environments.
Michael John Weston, Stuart John Piketh, Frédéric Burnet, Stephen Broccardo, Cyrielle Denjean, Thierry Bourrianne, and Paola Formenti
Atmos. Chem. Phys., 22, 10221–10245, https://doi.org/10.5194/acp-22-10221-2022, https://doi.org/10.5194/acp-22-10221-2022, 2022
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An aerosol-aware microphysics scheme is evaluated for fog cases in Namibia. AEROCLO-sA campaign observations are used to access and parameterise the model. The model cloud condensation nuclei activation is lower than the observations. The scheme is designed for clouds with updrafts, while fog typically forms in stable conditions. A pseudo updraft speed assigned to the lowest model levels helps achieve more realistic cloud droplet number concentration and size distribution in the model.
Lucas J. Sterzinger, Joseph Sedlar, Heather Guy, Ryan R. Neely III, and Adele L. Igel
Atmos. Chem. Phys., 22, 8973–8988, https://doi.org/10.5194/acp-22-8973-2022, https://doi.org/10.5194/acp-22-8973-2022, 2022
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Aerosol particles are required for cloud droplets to form, and the Arctic atmosphere often has much fewer aerosols than at lower latitudes. In this study, we investigate whether aerosol concentrations can drop so low as to no longer support a cloud. We use observations to initialize idealized model simulations to investigate a worst-case scenario where all aerosol is removed from the environment instantaneously. We find that this mechanism is possible in two cases and is unlikely in the third.
Pooja Verma and Ulrike Burkhardt
Atmos. Chem. Phys., 22, 8819–8842, https://doi.org/10.5194/acp-22-8819-2022, https://doi.org/10.5194/acp-22-8819-2022, 2022
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This paper investigates contrail ice formation within cirrus and the impact of natural cirrus on the contrail ice formation in the high-resolution ICON-LEM simulations over Germany. Contrail formation often leads to increases in cirrus ice crystal number concentration by a few orders of magnitude. Contrail formation is affected by pre-existing cirrus, leading to changes in contrail formation conditions and ice nucleation rates that can be significant in optically thick cirrus.
Mahnoosh Haghighatnasab, Jan Kretzschmar, Karoline Block, and Johannes Quaas
Atmos. Chem. Phys., 22, 8457–8472, https://doi.org/10.5194/acp-22-8457-2022, https://doi.org/10.5194/acp-22-8457-2022, 2022
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The impact of aerosols emitted by the Holuhraun volcanic eruption on liquid clouds was assessed from a pair of cloud-system-resolving simulations along with satellite retrievals. Inside and outside the plume were compared in terms of their statistical distributions. Analyses indicated enhancement for cloud droplet number concentration inside the volcano plume in model simulations and satellite retrievals, while there was on average a small effect on both liquid water path and cloud fraction.
Cheng You, Michael Tjernström, and Abhay Devasthale
Atmos. Chem. Phys., 22, 8037–8057, https://doi.org/10.5194/acp-22-8037-2022, https://doi.org/10.5194/acp-22-8037-2022, 2022
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In winter when solar radiation is absent in the Arctic, the poleward transport of heat and moisture into the high Arctic becomes the main contribution of Arctic warming. Over completely frozen ocean sectors, total surface energy budget is dominated by net long-wave heat, while over the Barents Sea, with an open ocean to the south, total net surface energy budget is dominated by the surface turbulent heat.
Shizuo Fu, Richard Rotunno, and Huiwen Xue
Atmos. Chem. Phys., 22, 7727–7738, https://doi.org/10.5194/acp-22-7727-2022, https://doi.org/10.5194/acp-22-7727-2022, 2022
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The convective updrafts near the sea-breeze fronts (SBFs) play important roles in initiating deep convection, but their characteristics are not well understood. By performing large-eddy simulations, we explain why the updrafts near the SBF are larger than but have similar strength to the updrafts ahead of the SBF. The results should also apply to other boundary-layer convergence zones similar to the SBF.
Prabhakar Shrestha, Silke Trömel, Raquel Evaristo, and Clemens Simmer
Atmos. Chem. Phys., 22, 7593–7618, https://doi.org/10.5194/acp-22-7593-2022, https://doi.org/10.5194/acp-22-7593-2022, 2022
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The study makes use of ensemble numerical simulations with forward operator to evaluate the simulated cloud and precipitation processes with radar observations. While comparing model data with radar has its own challenges due to errors in the forward operator and processed radar measurements, the model was generally found to underestimate the high reflectivity, width/magnitude (value) of ZDR columns and high precipitation.
Annakaisa von Lerber, Mario Mech, Annette Rinke, Damao Zhang, Melanie Lauer, Ana Radovan, Irina Gorodetskaya, and Susanne Crewell
Atmos. Chem. Phys., 22, 7287–7317, https://doi.org/10.5194/acp-22-7287-2022, https://doi.org/10.5194/acp-22-7287-2022, 2022
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Snowfall is an important climate indicator. However, microphysical snowfall processes are challenging for atmospheric models. In this study, the performance of a regional climate model is evaluated in modeling the spatial and temporal distribution of Arctic snowfall when compared to CloudSat satellite observations. Excellent agreement in averaged annual snowfall rates is found, and the shown methodology offers a promising diagnostic tool to investigate the shown differences further.
Yun Lin, Jiwen Fan, Pengfei Li, Lai-yung Ruby Leung, Paul J. DeMott, Lexie Goldberger, Jennifer Comstock, Ying Liu, Jong-Hoon Jeong, and Jason Tomlinson
Atmos. Chem. Phys., 22, 6749–6771, https://doi.org/10.5194/acp-22-6749-2022, https://doi.org/10.5194/acp-22-6749-2022, 2022
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How sea spray aerosols may affect cloud and precipitation over the region by acting as ice-nucleating particles (INPs) is unknown. We explored the effects of INPs from marine aerosols on orographic cloud and precipitation for an atmospheric river event observed during the 2015 ACAPEX field campaign. The marine INPs enhance the formation of ice and snow, leading to less shallow warm clouds but more mixed-phase and deep clouds. This work suggests models need to consider the impacts of marine INPs.
Xiaoqi Xu, Chunsong Lu, Yangang Liu, Shi Luo, Xin Zhou, Satoshi Endo, Lei Zhu, and Yuan Wang
Atmos. Chem. Phys., 22, 5459–5475, https://doi.org/10.5194/acp-22-5459-2022, https://doi.org/10.5194/acp-22-5459-2022, 2022
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A new entrainment–mixing parameterization which can be directly implemented in microphysics schemes without requiring the relative humidity of the entrained air is proposed based on the explicit mixing parcel model. The parameterization is implemented in the two-moment microphysics scheme and exhibits different effects on different types of clouds and even on different stages of stratocumulus clouds, which are affected by turbulent dissipation rate and aerosol concentration.
Ming Li, Husi Letu, Yiran Peng, Hiroshi Ishimoto, Yanluan Lin, Takashi Y. Nakajima, Anthony J. Baran, Zengyuan Guo, Yonghui Lei, and Jiancheng Shi
Atmos. Chem. Phys., 22, 4809–4825, https://doi.org/10.5194/acp-22-4809-2022, https://doi.org/10.5194/acp-22-4809-2022, 2022
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To build on the previous investigations of the Voronoi model in the remote sensing retrievals of ice cloud products, this paper developed an ice cloud parameterization scheme based on the single-scattering properties of the Voronoi model and evaluate it through simulations with the Community Integrated Earth System Model (CIESM). Compared with four representative ice cloud schemes, results show that the Voronoi model has good capabilities of ice cloud modeling in the climate model.
Ulrike Proske, Sylvaine Ferrachat, David Neubauer, Martin Staab, and Ulrike Lohmann
Atmos. Chem. Phys., 22, 4737–4762, https://doi.org/10.5194/acp-22-4737-2022, https://doi.org/10.5194/acp-22-4737-2022, 2022
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Cloud microphysical processes shape cloud properties and are therefore important to represent in climate models. Their parameterization has grown more complex, making the model results more difficult to interpret. Using sensitivity analysis we test how the global aerosol–climate model ECHAM-HAM reacts to changes to these parameterizations. The model is sensitive to the parameterization of ice crystal autoconversion but not to, e.g., self-collection, suggesting that it may be simplified.
Jaakko Ahola, Tomi Raatikainen, Muzaffer Ege Alper, Jukka-Pekka Keskinen, Harri Kokkola, Antti Kukkurainen, Antti Lipponen, Jia Liu, Kalle Nordling, Antti-Ilari Partanen, Sami Romakkaniemi, Petri Räisänen, Juha Tonttila, and Hannele Korhonen
Atmos. Chem. Phys., 22, 4523–4537, https://doi.org/10.5194/acp-22-4523-2022, https://doi.org/10.5194/acp-22-4523-2022, 2022
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Clouds are important for the climate, and cloud droplets have a significant role in cloud properties. Cloud droplets form when air rises and cools and water vapour condenses on small particles that can be natural or of anthropogenic origin. Currently, the updraft velocity, meaning how fast the air rises, is poorly represented in global climate models. In our study, we show three methods that will improve the depiction of updraft velocity and which properties are vital to updrafts.
Azusa Takeishi and Chien Wang
Atmos. Chem. Phys., 22, 4129–4147, https://doi.org/10.5194/acp-22-4129-2022, https://doi.org/10.5194/acp-22-4129-2022, 2022
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Nanometer- to micrometer-sized particles in the atmosphere, namely aerosols, play a crucial role in cloud formation as cloud droplets form on aerosols. This study uses a weather forecasting model to examine the impacts of a large emission of aerosol particles from biomass burning activities over Southeast Asia. We find that additional cloud droplets brought by fire-emitted particles can lead to taller and more reflective convective clouds with increased rainfall.
Ewe-Wei Saw and Xiaohui Meng
Atmos. Chem. Phys., 22, 3779–3788, https://doi.org/10.5194/acp-22-3779-2022, https://doi.org/10.5194/acp-22-3779-2022, 2022
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Collision–coagulation of small droplets in turbulent clouds leads to the production of rain. Turbulence causes droplet clustering and higher relative droplet velocities, and these should enhance the collision–coagulation rate. We find, surprisingly, that collision–coagulation starkly diminishes clustering and strongly alters relative velocities. We provide a theory that explains this result. Our results call for a new perspective on how we understand particle/droplet collision in clouds.
Tomi Raatikainen, Marje Prank, Jaakko Ahola, Harri Kokkola, Juha Tonttila, and Sami Romakkaniemi
Atmos. Chem. Phys., 22, 3763–3778, https://doi.org/10.5194/acp-22-3763-2022, https://doi.org/10.5194/acp-22-3763-2022, 2022
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Mineral dust or similar ice-nucleating particles (INPs) are needed to initiate cloud droplet freezing at temperatures common in shallow clouds. In this work we examine how INPs that are released from the sea surface impact marine clouds. Our high-resolution simulations show that turbulent updraughts carry these particles effectively up to the clouds, where they initiate cloud droplet freezing. Sea surface INP emissions become more important with decreasing background dust INP concentrations.
Kalli Furtado and Paul Field
Atmos. Chem. Phys., 22, 3391–3407, https://doi.org/10.5194/acp-22-3391-2022, https://doi.org/10.5194/acp-22-3391-2022, 2022
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The complex processes involved mean that no simple answer to this
question has so far been discovered: do aerosols increase or decrease precipitation? Using high-resolution weather simulations, we find a self-similar property of rainfall that is not affected by aerosols. Using this invariant, we can collapse all our simulations to a single curve. So, although aerosol effects on rain are many, there may be a universal constraint on the number of degrees of freedom needed to represent them.
Graham Feingold, Tom Goren, and Takanobu Yamaguchi
Atmos. Chem. Phys., 22, 3303–3319, https://doi.org/10.5194/acp-22-3303-2022, https://doi.org/10.5194/acp-22-3303-2022, 2022
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The evaluation of radiative forcing associated with aerosol–cloud interactions remains a significant source of uncertainty in future climate projections. Using high-resolution numerical model output, we mimic typical satellite retrieval methodologies to show that data aggregation can introduce significant error (hundreds of percent) in the cloud albedo susceptibility metric. Spatial aggregation errors tend to be countered by temporal aggregation errors.
Peter Kuma, Frida A.-M. Bender, Alex Schuddeboom, Adrian J. McDonald, and Øyvind Seland
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2022-184, https://doi.org/10.5194/acp-2022-184, 2022
Revised manuscript accepted for ACP
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We present a machine learning method of determining cloud types in climate model output and satellite data based on surface observations of cloud genera. We analyse cloud type biases and change with global mean near-surface temperature in a set of climate models, and show that there is a negative linear relationship between the error of cloud type occurrence and model climate sensitivity. This indicates that models with a better representation of the cloud types have higher climate sensitivity.
Xi Zhao and Xiaohong Liu
Atmos. Chem. Phys., 22, 2585–2600, https://doi.org/10.5194/acp-22-2585-2022, https://doi.org/10.5194/acp-22-2585-2022, 2022
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The goal of this study is to investigate the relative importance and interactions of primary and secondary ice production in the Arctic mixed-phase clouds. Our results show that the SIP is not only a result of ice crystals produced from ice nucleation, but also competes with the ice production; conversely, strong ice nucleation also suppresses SIP.
Yongjie Huang, Wei Wu, Greg M. McFarquhar, Ming Xue, Hugh Morrison, Jason Milbrandt, Alexei V. Korolev, Yachao Hu, Zhipeng Qu, Mengistu Wolde, Cuong Nguyen, Alfons Schwarzenboeck, and Ivan Heckman
Atmos. Chem. Phys., 22, 2365–2384, https://doi.org/10.5194/acp-22-2365-2022, https://doi.org/10.5194/acp-22-2365-2022, 2022
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Numerous small ice crystals in tropical convective storms are difficult to detect and could be potentially hazardous for commercial aircraft. Previous numerical simulations failed to reproduce this phenomenon and hypothesized that key microphysical processes are still lacking in current models to realistically simulate the phenomenon. This study uses numerical experiments to confirm the dominant role of secondary ice production in the formation of these large numbers of small ice crystals.
Christian Barthlott, Amirmahdi Zarboo, Takumi Matsunobu, and Christian Keil
Atmos. Chem. Phys., 22, 2153–2172, https://doi.org/10.5194/acp-22-2153-2022, https://doi.org/10.5194/acp-22-2153-2022, 2022
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The relative impact of cloud condensation nuclei (CCN) concentrations and the shape parameter of the cloud droplet size distribution is evaluated in realistic convection-resolving simulations. We find that an increase in the shape parameter can produce almost as large a variation in precipitation as a CCN increase from maritime to polluted conditions. The choice of the shape parameter may be more important than previously thought for determining cloud radiative characteristics.
Paraskevi Georgakaki, Georgia Sotiropoulou, Étienne Vignon, Anne-Claire Billault-Roux, Alexis Berne, and Athanasios Nenes
Atmos. Chem. Phys., 22, 1965–1988, https://doi.org/10.5194/acp-22-1965-2022, https://doi.org/10.5194/acp-22-1965-2022, 2022
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The modelling study focuses on the importance of ice multiplication processes in orographic mixed-phase clouds, which is one of the least understood cloud types in the climate system. We show that the consideration of ice seeding and secondary ice production through ice–ice collisional breakup is essential for correct predictions of precipitation in mountainous terrain, with important implications for radiation processes.
Zhiqiang Cui, Alan Blyth, Yahui Huang, Gary Lloyd, Thomas Choularton, Keith Bower, Paul Field, Rachel Hawker, and Lindsay Bennett
Atmos. Chem. Phys., 22, 1649–1667, https://doi.org/10.5194/acp-22-1649-2022, https://doi.org/10.5194/acp-22-1649-2022, 2022
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High concentrations of ice particles were observed at temperatures greater than about –8 C. The default scheme of the secondary ice production cannot explain the high concentrations. Relaxing the conditions for secondary ice production or considering dust aerosol alone is insufficient to produce the observed amount of ice particles. It is likely that multi-thermals play an important role in producing very high concentrations of secondary ice particles in some tropical clouds.
Justin A. Covert, David B. Mechem, and Zhibo Zhang
Atmos. Chem. Phys., 22, 1159–1174, https://doi.org/10.5194/acp-22-1159-2022, https://doi.org/10.5194/acp-22-1159-2022, 2022
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Stratocumulus play an important role in Earth's radiative balance. The simulation of these cloud systems in climate models is difficult due to the scale at which cloud microphysical processes occur compared with model grid sizes. In this study, we use large-eddy simulation to analyze subgrid-scale variability of cloud water and its implications on a cloud water to drizzle model enhancement factor E. We find current values of E may be too large and that E should be vertically dependent in models.
Xiangde Xu, Chan Sun, Deliang Chen, Tianliang Zhao, Jianjun Xu, Shengjun Zhang, Juan Li, Bin Chen, Yang Zhao, Hongxiong Xu, Lili Dong, Xiaoyun Sun, and Yan Zhu
Atmos. Chem. Phys., 22, 1149–1157, https://doi.org/10.5194/acp-22-1149-2022, https://doi.org/10.5194/acp-22-1149-2022, 2022
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A vertical transport window of tropospheric vapor exists on the Tibetan Plateau (TP). The TP's thermal forcing drives the vertical transport
windowof vapor in the troposphere. The effects of the TP's vertical transport window of vapor are of importance in global climate change.
Andreas Bier, Simon Unterstrasser, and Xavier Vancassel
Atmos. Chem. Phys., 22, 823–845, https://doi.org/10.5194/acp-22-823-2022, https://doi.org/10.5194/acp-22-823-2022, 2022
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We investigate contrail formation in an aircraft plume with a particle-based multi-trajectory 0D model. Due to the high plume heterogeneity, contrail ice crystals form first near the plume edge and then in the plume centre. The number of ice crystals varies strongly with ambient conditions and soot properties near the contrail formation threshold. Our results imply that the multi-trajectory approach does not necessarily lead to improved scientific results compared to a single mean trajectory.
Daniel Hernandez-Deckers, Toshihisa Matsui, and Ann M. Fridlind
Atmos. Chem. Phys., 22, 711–724, https://doi.org/10.5194/acp-22-711-2022, https://doi.org/10.5194/acp-22-711-2022, 2022
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We investigate how the concentration of aerosols (small particles that serve as seeds for cloud droplets) affect the dynamics of simulated clouds using two different frameworks, i.e., the traditional selection of cloudy rising grid points and tracking small-scale coherent rising features (cumulus thermals). By doing so, we find that these cumulus thermals reveal useful information about the coupling between internal cloud circulations and cloud droplet and raindrop formation.
Ian Boutle, Wayne Angevine, Jian-Wen Bao, Thierry Bergot, Ritthik Bhattacharya, Andreas Bott, Leo Ducongé, Richard Forbes, Tobias Goecke, Evelyn Grell, Adrian Hill, Adele L. Igel, Innocent Kudzotsa, Christine Lac, Bjorn Maronga, Sami Romakkaniemi, Juerg Schmidli, Johannes Schwenkel, Gert-Jan Steeneveld, and Benoît Vié
Atmos. Chem. Phys., 22, 319–333, https://doi.org/10.5194/acp-22-319-2022, https://doi.org/10.5194/acp-22-319-2022, 2022
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Fog forecasting is one of the biggest problems for numerical weather prediction. By comparing many models used for fog forecasting with others used for fog research, we hoped to help guide forecast improvements. We show some key processes that, if improved, will help improve fog forecasting, such as how water is deposited on the ground. We also showed that research models were not themselves a suitable baseline for comparison, and we discuss what future observations are required to improve them.
Hélène Bresson, Annette Rinke, Mario Mech, Daniel Reinert, Vera Schemann, Kerstin Ebell, Marion Maturilli, Carolina Viceto, Irina Gorodetskaya, and Susanne Crewell
Atmos. Chem. Phys., 22, 173–196, https://doi.org/10.5194/acp-22-173-2022, https://doi.org/10.5194/acp-22-173-2022, 2022
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Arctic warming is pronounced, and one factor in this is the poleward atmospheric transport of heat and moisture. This study assesses the 4D structure of an Arctic moisture intrusion event which occurred in June 2017. For the first time, high-resolution pan-Arctic ICON simulations are performed and compared with global models, reanalysis, and observations. Results show the added value of high resolution in the event representation and the impact of the intrusion on the surface energy fluxes.
Manuel Baumgartner, Christian Rolf, Jens-Uwe Grooß, Julia Schneider, Tobias Schorr, Ottmar Möhler, Peter Spichtinger, and Martina Krämer
Atmos. Chem. Phys., 22, 65–91, https://doi.org/10.5194/acp-22-65-2022, https://doi.org/10.5194/acp-22-65-2022, 2022
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An important mechanism for the appearance of ice particles in the upper troposphere at low temperatures is homogeneous nucleation. This process is commonly described by the
Koop line, predicting the humidity at freezing. However, laboratory measurements suggest that the freezing humidities are above the Koop line, motivating the present study to investigate the influence of different physical parameterizations on the homogeneous freezing with the help of a detailed numerical model.
Ramon Campos Braga, Barbara Ervens, Daniel Rosenfeld, Meinrat O. Andreae, Jan-David Förster, Daniel Fütterer, Lianet Hernández Pardo, Bruna A. Holanda, Tina Jurkat-Witschas, Ovid O. Krüger, Oliver Lauer, Luiz A. T. Machado, Christopher Pöhlker, Daniel Sauer, Christiane Voigt, Adrian Walser, Manfred Wendisch, Ulrich Pöschl, and Mira L. Pöhlker
Atmos. Chem. Phys., 21, 17513–17528, https://doi.org/10.5194/acp-21-17513-2021, https://doi.org/10.5194/acp-21-17513-2021, 2021
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Interactions of aerosol particles with clouds represent a large uncertainty in estimates of climate change. Properties of aerosol particles control their ability to act as cloud condensation nuclei. Using aerosol measurements in the Amazon, we performed model studies to compare predicted and measured cloud droplet number concentrations at cloud bases. Our results confirm previous estimates of particle hygroscopicity in this region.
Yanda Zhang, Fangqun Yu, Gan Luo, Jiwen Fan, and Shuai Liu
Atmos. Chem. Phys., 21, 17433–17451, https://doi.org/10.5194/acp-21-17433-2021, https://doi.org/10.5194/acp-21-17433-2021, 2021
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This paper explores the impacts of dust on summertime convective cloud and precipitation through a numerical experiment. The result indicates that the long-range-transported dust can notably affect the properties of convective cloud and precipitation by enhancing immersion freezing and invigorating convection. We also analyze the different dust effects predicted by the Morrison and SBM schemes, which are partially attributed to the saturation adjustment approach utilized in the bulk schemes.
Rachel E. Hawker, Annette K. Miltenberger, Jill S. Johnson, Jonathan M. Wilkinson, Adrian A. Hill, Ben J. Shipway, Paul R. Field, Benjamin J. Murray, and Ken S. Carslaw
Atmos. Chem. Phys., 21, 17315–17343, https://doi.org/10.5194/acp-21-17315-2021, https://doi.org/10.5194/acp-21-17315-2021, 2021
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We find that ice-nucleating particles (INPs), aerosols that can initiate the freezing of cloud droplets, cause substantial changes to the properties of radiatively important convectively generated anvil cirrus. The number concentration of INPs had a large effect on ice crystal number concentration while the INP temperature dependence controlled ice crystal size and cloud fraction. The results indicate information on INP number and source is necessary for the representation of cloud glaciation.
Markus Karrer, Axel Seifert, Davide Ori, and Stefan Kneifel
Atmos. Chem. Phys., 21, 17133–17166, https://doi.org/10.5194/acp-21-17133-2021, https://doi.org/10.5194/acp-21-17133-2021, 2021
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Modeling precipitation is of great relevance, e.g., for mitigating damage caused by extreme weather. A key component in accurate precipitation modeling is aggregation, i.e., sticking together of snowflakes. Simulating aggregation is difficult due to multiple parameters that are not well-known. Knowing how these parameters affect aggregation can help its simulation. We put new parameters in the model and select a combination of parameters with which the model can simulate observations better.
Samira Khodayar, Silvio Davolio, Paolo Di Girolamo, Cindy Lebeaupin Brossier, Emmanouil Flaounas, Nadia Fourrie, Keun-Ok Lee, Didier Ricard, Benoit Vie, Francois Bouttier, Alberto Caldas-Alvarez, and Veronique Ducrocq
Atmos. Chem. Phys., 21, 17051–17078, https://doi.org/10.5194/acp-21-17051-2021, https://doi.org/10.5194/acp-21-17051-2021, 2021
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Heavy precipitation (HP) constitutes a major meteorological threat in the western Mediterranean. Every year, recurrent events affect the area with fatal consequences. Despite this being a well-known issue, open questions still remain. The understanding of the underlying mechanisms and the modeling representation of the events must be improved. In this article we present the most recent lessons learned from the Hydrological Cycle in the Mediterranean Experiment (HyMeX).
Seoung Soo Lee, Kyung-Ja Ha, Manguttathil Gopalakrishnan Manoj, Mohammad Kamruzzaman, Hyungjun Kim, Nobuyuki Utsumi, Youtong Zheng, Byung-Gon Kim, Chang Hoon Jung, Junshik Um, Jianping Guo, Kyoung Ock Choi, and Go-Un Kim
Atmos. Chem. Phys., 21, 16843–16868, https://doi.org/10.5194/acp-21-16843-2021, https://doi.org/10.5194/acp-21-16843-2021, 2021
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