Articles | Volume 25, issue 1
https://doi.org/10.5194/acp-25-491-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/acp-25-491-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
15 Jan 2025
Research article |
| 15 Jan 2025
| 15 Jan 2025
A satellite-based analysis of semi-direct effects of biomass burning aerosols on fog and low-cloud dissipation in the Namib Desert
Karlsruhe Institute of Technology (KIT), Institute of Meteorology and Climate Research, Karlsruhe, Germany
Karlsruhe Institute of Technology (KIT), Institute of Photogrammetry and Remote Sensing, Karlsruhe, Germany
Hendrik Andersen
Karlsruhe Institute of Technology (KIT), Institute of Meteorology and Climate Research, Karlsruhe, Germany
Karlsruhe Institute of Technology (KIT), Institute of Photogrammetry and Remote Sensing, Karlsruhe, Germany
Jan Cermak
Karlsruhe Institute of Technology (KIT), Institute of Meteorology and Climate Research, Karlsruhe, Germany
Karlsruhe Institute of Technology (KIT), Institute of Photogrammetry and Remote Sensing, Karlsruhe, Germany
Paola Formenti
Université Paris Cité and Univ Paris Est Creteil, CNRS, LISA, 75013 Paris, France
Eva Pauli
Karlsruhe Institute of Technology (KIT), Institute of Meteorology and Climate Research, Karlsruhe, Germany
Karlsruhe Institute of Technology (KIT), Institute of Photogrammetry and Remote Sensing, Karlsruhe, Germany
Julian Quinting
Karlsruhe Institute of Technology (KIT), Institute of Meteorology and Climate Research, Karlsruhe, Germany
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Claudia Di Biagio, Elisa Bru, Avila Orta, Servanne Chevaillier, Clarissa Baldo, Antonin Bergé, Mathieu Cazaunau, Sandra Lafon, Sophie Nowak, Edouard Pangui, Meinrat O. Andreae, Pavla Dagsson-Waldhauserova, Kebonyethata Dintwe, Konrad Kandler, James S. King, Amelie Chaput, Gregory S. Okin, Stuart Piketh, Thuraya Saeed, David Seibert, Zongbo Shi, Earle Williams, Pasquale Sellitto, and Paola Formenti
EGUsphere, https://doi.org/10.5194/egusphere-2025-3512, https://doi.org/10.5194/egusphere-2025-3512, 2025
This preprint is open for discussion and under review for Atmospheric Chemistry and Physics (ACP).
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Spectroscopy measurements show that the absorbance of dust in the far-infrared up to 25 μm is comparable in intensity to that in the mid-infrared (3–15μm) suggesting its relevance for dust direct radiative effect. Data evidence different absorption signatures for high and low/mid latitude dust, due to differences in mineralogical composition. These differences could be used to characterise the mineralogy and differentiate the origin of airborne dust based on infrared remote sensing observations.
Deepanshu Malik, Hendrik Andersen, Jan Cermak, Roland Vogt, and Bianca Adler
EGUsphere, https://doi.org/10.5194/egusphere-2025-2645, https://doi.org/10.5194/egusphere-2025-2645, 2025
This preprint is open for discussion and under review for Atmospheric Chemistry and Physics (ACP).
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We investigated cloud base height changes in the Namib Desert and developed a method to estimate it using ground-based humidity data. This improves fog monitoring by distinguishing fog from low clouds, which satellites alone cannot reliably do. Our results reveal diurnal patterns and linkages to coastal proximity in the vertical dynamics of fog and low clouds, highlighting key atmospheric processes with potential importance for future research.
Abdulaziz T. Yakubu, Danitza Klopper, Henno Havenga, Roelof Burger, Paola Formenti, and Stuart J. Piketh
EGUsphere, https://doi.org/10.5194/egusphere-2025-1827, https://doi.org/10.5194/egusphere-2025-1827, 2025
This preprint is open for discussion and under review for Atmospheric Chemistry and Physics (ACP).
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Low-level inversions experienced along the Namibia coast and adjacent ocean have implications for air pollutant dispersion and low clouds. These affect air quality, human health, radiative forcing and climate change. We used reanalysis and satellite datasets to understand inversion properties over the region. The result shows inversion prominence at night and in winter, seasonally influences pollutant trapping and initiates stratocumulus clouds formation, but is not liable for their extent.
Chenjie Yu, Paola Formenti, Joel F. de Brito, Astrid Bauville, Antonin Bergé, Hichem Bouzidi, Mathieu Cazaunau, Manuela Cirtog, Claudia Di Biagio, Ludovico Di Antonio, Cécile Gaimoz, Franck Maisonneuve, Pascal Zapf, Tobias Seubert, Simone T. Andersen, Patrick Dewald, Gunther N. T. E. Türk, John N. Crowley, Alexandre Kukui, Chaoyang Xue, Cyrielle Denjean, Olivier Garrouste, Jean-Claude Etienne, Huihui Wu, James D. Allan, Dantong Liu, Yangzhou Wu, Christopher Cantrell, and Vincent Michoud
EGUsphere, https://doi.org/10.5194/egusphere-2025-2667, https://doi.org/10.5194/egusphere-2025-2667, 2025
This preprint is open for discussion and under review for Atmospheric Chemistry and Physics (ACP).
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We presented a field measurement in a Paris suburban forest region to characterise the impacts of photochemical aging process on aerosol physical chemical properties. Photochemical production of organic aerosols increased forest fine particle mass and significantly enhanced absorption of short-wavelength sunlight. This study highlights the critical need to incorporate light absorbing carbonaceous particles formation mechanisms into models to accurately simulate their direct radiative impacts.
Johannes Heuser, Claudia Di Biagio, Jérôme Yon, Mathieu Cazaunau, Antonin Bergé, Edouard Pangui, Marco Zanatta, Laura Renzi, Angela Marinoni, Satoshi Inomata, Chenjie Yu, Vera Bernardoni, Servanne Chevaillier, Daniel Ferry, Paolo Laj, Michel Maillé, Dario Massabò, Federico Mazzei, Gael Noyalet, Hiroshi Tanimoto, Brice Temime-Roussel, Roberta Vecchi, Virginia Vernocchi, Paola Formenti, Bénédicte Picquet-Varrault, and Jean-François Doussin
Atmos. Chem. Phys., 25, 6407–6428, https://doi.org/10.5194/acp-25-6407-2025, https://doi.org/10.5194/acp-25-6407-2025, 2025
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The spectral optical properties of combustion soot aerosols with varying black (BC) and brown carbon (BrC) content were studied in an atmospheric simulation chamber. Measurements of the mass spectral absorption cross section (MAC), supplemented by literature data, allowed us to establish a generalised exponential relationship between the spectral absorption and the elemental-to-total-carbon ratio (EC / TC) in soot. This relationship can provide a useful tool for modelling the properties of soot.
Diana L. Pereira, Aline Gratien, Chiara Giorio, Emmanuelle Mebold, Thomas Bertin, Cécile Gaimoz, Jean-François Doussin, and Paola Formenti
EGUsphere, https://doi.org/10.5194/egusphere-2025-2393, https://doi.org/10.5194/egusphere-2025-2393, 2025
This preprint is open for discussion and under review for Atmospheric Measurement Techniques (AMT).
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This study provides two methods for the quantification of molecular markers to improve the description of secondary organic aerosols using chromatographic techniques coupled with mass spectrometry. Compounds from various chemical functionalities (alcohols, acids, aldehydes), from biogenic and anthropogenic origin, were identified. Improved method performance was observed for nitro compounds, which have been associated with anthropogenic activities.
Simone T. Andersen, Rolf Sander, Patrick Dewald, Laura Wüst, Tobias Seubert, Gunther N. T. E. Türk, Jan Schuladen, Max R. McGillen, Chaoyang Xue, Abdelwahid Mellouki, Alexandre Kukui, Vincent Michoud, Manuela Cirtog, Mathieu Cazaunau, Astrid Bauville, Hichem Bouzidi, Paola Formenti, Cyrielle Denjean, Jean-Claude Etienne, Olivier Garrouste, Christopher Cantrell, Jos Lelieveld, and John N. Crowley
Atmos. Chem. Phys., 25, 5893–5909, https://doi.org/10.5194/acp-25-5893-2025, https://doi.org/10.5194/acp-25-5893-2025, 2025
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Measurements and modelling of reactive nitrogen gases observed in a suburban temperate forest in Rambouillet, France, circa 50 km southwest of Paris in 2022 indicate that the biosphere rapidly scavenges organic nitrates of mixed biogenic and anthropogenic origin, resulting in short lifetimes for, for example, alkyl nitrates and peroxy nitrates.
Ludovico Di Antonio, Matthias Beekmann, Guillaume Siour, Vincent Michoud, Christopher Cantrell, Astrid Bauville, Antonin Bergé, Mathieu Cazaunau, Servanne Chevaillier, Manuela Cirtog, Joel F. de Brito, Paola Formenti, Cecile Gaimoz, Olivier Garret, Aline Gratien, Valérie Gros, Martial Haeffelin, Lelia N. Hawkins, Simone Kotthaus, Gael Noyalet, Diana L. Pereira, Jean-Eudes Petit, Eva Drew Pronovost, Véronique Riffault, Chenjie Yu, Gilles Foret, Jean-François Doussin, and Claudia Di Biagio
Atmos. Chem. Phys., 25, 4803–4831, https://doi.org/10.5194/acp-25-4803-2025, https://doi.org/10.5194/acp-25-4803-2025, 2025
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The summer of 2022 has been considered a proxy for future climate scenarios due to its hot and dry conditions. In this paper, we use the measurements from the Atmospheric Chemistry of the Suburban Forest (ACROSS) campaign, conducted in the Paris area in June–July 2022, along with observations from existing networks, to evaluate a 3D chemistry transport model (WRF–CHIMERE) simulation. Results are shown to be satisfactory, allowing us to explain the gas and aerosol variability at the campaign sites.
Diana L. Pereira, Chiara Giorio, Aline Gratien, Alexander Zherebker, Gael Noyalet, Servanne Chevaillier, Stéphanie Alage, Elie Almarj, Antonin Bergé, Thomas Bertin, Mathieu Cazaunau, Patrice Coll, Ludovico Di Antonio, Sergio Harb, Johannes Heuser, Cécile Gaimoz, Oscar Guillemant, Brigitte Language, Olivier Lauret, Camilo Macias, Franck Maisonneuve, Bénédicte Picquet-Varrault, Raquel Torres, Sylvain Triquet, Pascal Zapf, Lelia Hawkins, Drew Pronovost, Sydney Riley, Pierre-Marie Flaud, Emilie Perraudin, Pauline Pouyes, Eric Villenave, Alexandre Albinet, Olivier Favez, Robin Aujay-Plouzeau, Vincent Michoud, Christopher Cantrell, Manuela Cirtog, Claudia Di Biagio, Jean-François Doussin, and Paola Formenti
Atmos. Chem. Phys., 25, 4885–4905, https://doi.org/10.5194/acp-25-4885-2025, https://doi.org/10.5194/acp-25-4885-2025, 2025
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In order to study aerosols in environments influenced by anthropogenic and biogenic emissions, we performed analyses of samples collected during the ACROSS (Atmospheric Chemistry Of the Suburban Forest) campaign in summer 2022 in the greater Paris area. After analysis of the chemical composition by means of total carbon determination and high-resolution mass spectrometry, this work highlights the influence of anthropogenic inputs on the chemical composition of both urban and forested areas.
Babak Jahani, Steffen Karalus, Julia Fuchs, Tobias Zech, Marina Zara, and Jan Cermak
Atmos. Meas. Tech., 18, 1927–1941, https://doi.org/10.5194/amt-18-1927-2025, https://doi.org/10.5194/amt-18-1927-2025, 2025
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Fog and low stratus (FLS) are both persistent clouds close to the Earth's surface. This study introduces a new machine-learning-based algorithm developed for the Meteosat Second Generation geostationary satellites that can provide a coherent and detailed view of FLS development over large areas over the 24 h day cycle.
Edgar Dolores-Tesillos, Olivia Martius, and Julian Quinting
Weather Clim. Dynam., 6, 471–487, https://doi.org/10.5194/wcd-6-471-2025, https://doi.org/10.5194/wcd-6-471-2025, 2025
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An accurate representation of synoptic weather systems in climate models is required to estimate their societal and economic impacts under climate warming. Current climate models poorly represent the frequency of atmospheric blocking. Few studies have analysed the role of moist processes as a source of the bias of blocks. Here, we implement ELIAS2.0, a deep-learning tool, to validate the representation of moist processes in CMIP6 models and their link to the Euro-Atlantic blocking biases.
Paola Formenti, Chiara Giorio, Karine Desboeufs, Alexander Zherebker, Marco Gaetani, Clarissa Baldo, Gautier Landrot, Simona Montebello, Servanne Chevaillier, Sylvain Triquet, Guillaume Siour, Claudia Di Biagio, Francesco Battaglia, Jean-François Doussin, Anais Feron, Andreas Namwoonde, and Stuart John Piketh
EGUsphere, https://doi.org/10.5194/egusphere-2025-446, https://doi.org/10.5194/egusphere-2025-446, 2025
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The elemental composition and solubility of several metals, including iron, at a coastal site in Namibia in August–September 2017, indicate that natural and anthropogenic dust had different solubility depending on mineralogy but mostly to the processing by fluoride ions from marine emissions, pointing out to the complexity of atmospheric/oceanic interactions in this region of the world influenced by the Benguela current and significant aerosol load.
Ludovico Di Antonio, Claudia Di Biagio, Paola Formenti, Aline Gratien, Vincent Michoud, Christopher Cantrell, Astrid Bauville, Antonin Bergé, Mathieu Cazaunau, Servanne Chevaillier, Manuela Cirtog, Patrice Coll, Barbara D'Anna, Joel F. de Brito, David O. De Haan, Juliette R. Dignum, Shravan Deshmukh, Olivier Favez, Pierre-Marie Flaud, Cecile Gaimoz, Lelia N. Hawkins, Julien Kammer, Brigitte Language, Franck Maisonneuve, Griša Močnik, Emilie Perraudin, Jean-Eudes Petit, Prodip Acharja, Laurent Poulain, Pauline Pouyes, Eva Drew Pronovost, Véronique Riffault, Kanuri I. Roundtree, Marwa Shahin, Guillaume Siour, Eric Villenave, Pascal Zapf, Gilles Foret, Jean-François Doussin, and Matthias Beekmann
Atmos. Chem. Phys., 25, 3161–3189, https://doi.org/10.5194/acp-25-3161-2025, https://doi.org/10.5194/acp-25-3161-2025, 2025
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The spectral complex refractive index (CRI) and single scattering albedo were retrieved from submicron aerosol measurements at three sites within the greater Paris area during the ACROSS field campaign (June–July 2022). Measurements revealed urban emission impact on surrounding areas. CRI full period averages at 520 nm were 1.41 – 0.037i (urban), 1.52 – 0.038i (peri-urban), and 1.50 – 0.025i (rural). Organic aerosols dominated the aerosol mass and contributed up to 22 % of absorption at 370 nm.
Francesco Battaglia, Paola Formenti, Chiara Giorio, Mathieu Cazaunau, Edouard Pangui, Antonin Bergé, Aline Gratien, Thomas Bertin, Joël F. de Brito, Manolis N. Romanias, Vincent Michoud, Clarissa Baldo, Servanne Chevaillier, Gaël Noyalet, Philippe Decorse, Bénédicte Picquet-Varrault, and Jean-François Doussin
EGUsphere, https://doi.org/10.5194/egusphere-2024-4073, https://doi.org/10.5194/egusphere-2024-4073, 2025
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This paper presents an experimental investigation of the interactions between glyoxal, an important volatile organic compound, and mineral dust particles of size and composition typical of natural conditions. We show that their interactions modifies in a definitive way the concentrations of the gas phase and the properties of the dust, which could have important implications of the atmospheric composition and the Earth's climate.
Chiara Giorio, Anne Monod, Valerio Di Marco, Pierre Herckes, Denise Napolitano, Amy Sullivan, Gautier Landrot, Daniel Warnes, Marika Nasti, Sara D'Aronco, Agathe Gérardin, Nicolas Brun, Karine Desboeufs, Sylvain Triquet, Servanne Chevaillier, Claudia Di Biagio, Francesco Battaglia, Frédéric Burnet, Stuart J. Piketh, Andreas Namwoonde, Jean-François Doussin, and Paola Formenti
EGUsphere, https://doi.org/10.5194/egusphere-2024-4140, https://doi.org/10.5194/egusphere-2024-4140, 2025
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A comparison between the solubility of trace metals in pairs of total suspended particulate (TSP) and fog water samples collected in Henties Bay, Namibia, during the AEROCLO-sA field campaign is presented. We found enhanced solubility of metals in fog samples which we attributed to metal-ligand complexes formation in the early stages of particle activation into droplets which can then remain in a kinetically stable form in fog or lead to the formation of colloidal nanoparticles.
Lu Zhang, Michal Segal-Rozenhaimer, Haochi Che, Caroline Dang, Junying Sun, Ye Kuang, Paola Formenti, and Steven G. Howell
Atmos. Chem. Phys., 24, 13849–13864, https://doi.org/10.5194/acp-24-13849-2024, https://doi.org/10.5194/acp-24-13849-2024, 2024
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Using airborne measurements over the southeast Atlantic Ocean, we examined how much moisture aerosols take up during Africa’s biomass burning season. Our study revealed the important role of organic aerosols and introduced a predictive model for moisture uptake, accounting for organics, sulfate, and black carbon, summarizing results from various campaigns. These findings improve our understanding of aerosol–moisture interactions and their radiative effects in this climatically critical region.
Deifilia To, Julian Quinting, Gholam Ali Hoshyaripour, Markus Götz, Achim Streit, and Charlotte Debus
Geosci. Model Dev., 17, 8873–8884, https://doi.org/10.5194/gmd-17-8873-2024, https://doi.org/10.5194/gmd-17-8873-2024, 2024
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Pangu-Weather is a breakthrough machine learning model in medium-range weather forecasting that considers 3D atmospheric information. We show that using a simpler 2D framework improves robustness, speeds up training, and reduces computational needs by 20 %–30 %. We introduce a training procedure that varies the importance of atmospheric variables over time to speed up training convergence. Decreasing computational demand increases the accessibility of training and working with the model.
Yichen Jia, Hendrik Andersen, and Jan Cermak
Atmos. Chem. Phys., 24, 13025–13045, https://doi.org/10.5194/acp-24-13025-2024, https://doi.org/10.5194/acp-24-13025-2024, 2024
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We present a near-global observation-based explainable machine learning framework to quantify the response of cloud fraction (CLF) of marine low clouds to cloud droplet number concentration (Nd), accounting for the covariations with meteorological factors. This approach provides a novel data-driven method to analyse the CLF adjustment by assessing the CLF sensitivity to Nd and numerous meteorological factors as well as the dependence of the Nd–CLF sensitivity on the meteorological conditions.
Paola Formenti and Claudia Di Biagio
Earth Syst. Sci. Data, 16, 4995–5007, https://doi.org/10.5194/essd-16-4995-2024, https://doi.org/10.5194/essd-16-4995-2024, 2024
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Particles from deserts and semi-vegetated areas (mineral dust) are important for Earth's climate and human health, notably depending on their size. In this paper we collect and make a synthesis of a body of these observations since 1972 in order to provide researchers modeling Earth's climate and developing satellite observations from space with a simple way of confronting their results and understanding their validity.
Mégane Ventura, Fabien Waquet, Isabelle Chiapello, Gérard Brogniez, Frédéric Parol, Frédérique Auriol, Rodrigue Loisil, Cyril Delegove, Luc Blarel, Oleg Dubovik, Marc Mallet, Cyrille Flamant, and Paola Formenti
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2024-121, https://doi.org/10.5194/amt-2024-121, 2024
Revised manuscript accepted for AMT
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Biomass burning aerosols (BBA) from Central Africa, are transported above stratocumulus clouds. The absorption of solar energy by aerosols induce warming, altering the clouds dynamics. We developed an approach that combines polarimeter and lidar to quantify it. This methodology is assessed during the AEROCLO-SA campaign. To validate it, we used flux measurements acquired during aircraft loop descents. Major perspective is the generalization of this method to the global level.
Sarah Wilson Kemsley, Paulo Ceppi, Hendrik Andersen, Jan Cermak, Philip Stier, and Peer Nowack
Atmos. Chem. Phys., 24, 8295–8316, https://doi.org/10.5194/acp-24-8295-2024, https://doi.org/10.5194/acp-24-8295-2024, 2024
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Aiming to inform parameter selection for future observational constraint analyses, we incorporate five candidate meteorological drivers specifically targeting high clouds into a cloud controlling factor framework within a range of spatial domain sizes. We find a discrepancy between optimal domain size for predicting locally and globally aggregated cloud radiative anomalies and identify upper-tropospheric static stability as an important high-cloud controlling factor.
Chenjie Yu, Edouard Pangui, Kevin Tu, Mathieu Cazaunau, Maxime Feingesicht, Landsheere Xavier, Thierry Bourrianne, Vincent Michoud, Christopher Cantrell, Timothy B. Onasch, Andrew Freedman, and Paola Formenti
Atmos. Meas. Tech., 17, 3419–3437, https://doi.org/10.5194/amt-17-3419-2024, https://doi.org/10.5194/amt-17-3419-2024, 2024
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To meet the requirements for measuring aerosol optical properties on airborne platforms and conducting dual-wavelength measurements, we introduced A2S2, an airborne dual-wavelength cavity-attenuated phase-shift single monitor. This study reports the results in the laboratory and an aircraft campaign over Paris and its surrounding regions. The results demonstrate A2S2's reliability in measuring aerosol optical properties at both wavelengths and its suitability for future aircraft campaigns.
Vincenzo Obiso, María Gonçalves Ageitos, Carlos Pérez García-Pando, Jan P. Perlwitz, Gregory L. Schuster, Susanne E. Bauer, Claudia Di Biagio, Paola Formenti, Kostas Tsigaridis, and Ron L. Miller
Atmos. Chem. Phys., 24, 5337–5367, https://doi.org/10.5194/acp-24-5337-2024, https://doi.org/10.5194/acp-24-5337-2024, 2024
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We calculate the dust direct radiative effect (DRE) in an Earth system model accounting for regionally varying soil mineralogy through a new observationally constrained method. Linking dust absorption at solar wavelengths to the varying amount of specific minerals (i.e., iron oxides) improves the modeled range of dust single scattering albedo compared to observations and increases the global cooling by dust. Our results may contribute to improved estimates of the dust DRE and its climate impact.
Cyrille Flamant, Jean-Pierre Chaboureau, Marco Gaetani, Kerstin Schepanski, and Paola Formenti
Atmos. Chem. Phys., 24, 4265–4288, https://doi.org/10.5194/acp-24-4265-2024, https://doi.org/10.5194/acp-24-4265-2024, 2024
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In the austral dry season, the atmospheric composition over southern Africa is dominated by biomass burning aerosols and terrigenous aerosols (so-called mineral dust). This study suggests that the radiative effect of biomass burning aerosols needs to be taken into account to properly forecast dust emissions in Namibia.
Anil Kumar Mandariya, Junteng Wu, Anne Monod, Paola Formenti, Bénédicte Picquet-Varrault, Mathieu Cazaunau, Stephan Mertes, Laurent Poulain, Antonin Berge, Edouard Pangui, Andreas Tilgner, Thomas Schaefer, Liang Wen, Hartmut Herrmann, and Jean-François Doussin
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2023-206, https://doi.org/10.5194/amt-2023-206, 2024
Publication in AMT not foreseen
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An optimized and controlled protocol for generating quasi-adiabatic expansion clouds under simulated dark and light conditions was presented. The irradiated clouds clearly showed a gradual activation of seed particles into droplets. In contrast, non-irradiated clouds faced a flash activation. This paper will lay the foundation for multiphase photochemical studies implying water-soluble volatile organic compounds and particulate matter formation during cloud formation-evaporation cycles.
Karine Desboeufs, Paola Formenti, Raquel Torres-Sánchez, Kerstin Schepanski, Jean-Pierre Chaboureau, Hendrik Andersen, Jan Cermak, Stefanie Feuerstein, Benoit Laurent, Danitza Klopper, Andreas Namwoonde, Mathieu Cazaunau, Servanne Chevaillier, Anaïs Feron, Cécile Mirande-Bret, Sylvain Triquet, and Stuart J. Piketh
Atmos. Chem. Phys., 24, 1525–1541, https://doi.org/10.5194/acp-24-1525-2024, https://doi.org/10.5194/acp-24-1525-2024, 2024
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This study investigates the fractional solubility of iron (Fe) in dust particles along the coast of Namibia, a critical region for the atmospheric Fe supply of the South Atlantic Ocean. Our results suggest a possible two-way interplay whereby marine biogenic emissions from the coastal marine ecosystems into the atmosphere would increase the solubility of Fe-bearing dust by photo-reduction processes. The subsequent deposition of soluble Fe could act to further enhance marine biogenic emissions.
Julian F. Quinting, Christian M. Grams, Edmund Kar-Man Chang, Stephan Pfahl, and Heini Wernli
Weather Clim. Dynam., 5, 65–85, https://doi.org/10.5194/wcd-5-65-2024, https://doi.org/10.5194/wcd-5-65-2024, 2024
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Research in the last few decades has revealed that rapidly ascending airstreams in extratropical cyclones have an important effect on the evolution of downstream weather and predictability. In this study, we show that the occurrence of these airstreams over the North Pacific is modulated by tropical convection. Depending on the modulation, known atmospheric circulation patterns evolve quite differently, which may affect extended-range predictions in the Atlantic–European region.
Lu Zhang, Michal Segal-Rozenhaimer, Haochi Che, Caroline Dang, Junying Sun, Ye Kuang, and Paola Formenti
EGUsphere, https://doi.org/10.5194/egusphere-2023-2319, https://doi.org/10.5194/egusphere-2023-2319, 2023
Preprint archived
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Our study examined the interaction between atmospheric particles and moisture over the south-eastern Atlantic Ocean during the biomass burning seasons in Africa. We found that organic components of these particles play a more important role in aerosol-moisture interactions than previously expected. This discovery is important as such interactions impact radiation and climate. Current climate models might need better representations of the moisture-absorbing properties of organic aerosols.
Ludovico Di Antonio, Claudia Di Biagio, Gilles Foret, Paola Formenti, Guillaume Siour, Jean-François Doussin, and Matthias Beekmann
Atmos. Chem. Phys., 23, 12455–12475, https://doi.org/10.5194/acp-23-12455-2023, https://doi.org/10.5194/acp-23-12455-2023, 2023
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Long-term (2000–2021) 1 km resolution satellite data have been used to investigate the climatological aerosol optical depth (AOD) variability and trends at different scales in Europe. Average enhancements of the local-to-regional AOD ratio at 550 nm of 57 %, 55 %, 39 % and 32 % are found for large metropolitan areas such as Barcelona, Lisbon, Paris and Athens, respectively, suggesting a non-negligible enhancement of the aerosol burden through local emissions.
Hendrik Andersen, Jan Cermak, Alyson Douglas, Timothy A. Myers, Peer Nowack, Philip Stier, Casey J. Wall, and Sarah Wilson Kemsley
Atmos. Chem. Phys., 23, 10775–10794, https://doi.org/10.5194/acp-23-10775-2023, https://doi.org/10.5194/acp-23-10775-2023, 2023
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This study uses an observation-based cloud-controlling factor framework to study near-global sensitivities of cloud radiative effects to a large number of meteorological and aerosol controls. We present near-global sensitivity patterns to selected thermodynamic, dynamic, and aerosol factors and discuss the physical mechanisms underlying the derived sensitivities. Our study hopes to guide future analyses aimed at constraining cloud feedbacks and aerosol–cloud interactions.
Clarissa Baldo, Paola Formenti, Claudia Di Biagio, Gongda Lu, Congbo Song, Mathieu Cazaunau, Edouard Pangui, Jean-Francois Doussin, Pavla Dagsson-Waldhauserova, Olafur Arnalds, David Beddows, A. Robert MacKenzie, and Zongbo Shi
Atmos. Chem. Phys., 23, 7975–8000, https://doi.org/10.5194/acp-23-7975-2023, https://doi.org/10.5194/acp-23-7975-2023, 2023
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This paper presents new shortwave spectral complex refractive index and single scattering albedo data for Icelandic dust. Our results show that the imaginary part of the complex refractive index of Icelandic dust is at the upper end of the range of low-latitude dust. Furthermore, we observed that Icelandic dust is more absorbing towards the near-infrared, which we attribute to its high magnetite content. These findings are important for modeling dust aerosol radiative effects in the Arctic.
Axel Seifert, Vanessa Bachmann, Florian Filipitsch, Jochen Förstner, Christian M. Grams, Gholam Ali Hoshyaripour, Julian Quinting, Anika Rohde, Heike Vogel, Annette Wagner, and Bernhard Vogel
Atmos. Chem. Phys., 23, 6409–6430, https://doi.org/10.5194/acp-23-6409-2023, https://doi.org/10.5194/acp-23-6409-2023, 2023
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We investigate how mineral dust can lead to the formation of cirrus clouds. Dusty cirrus clouds lead to a reduction in solar radiation at the surface and, hence, a reduced photovoltaic power generation. Current weather prediction systems are not able to predict this interaction between mineral dust and cirrus clouds. We have developed a new physical description of the formation of dusty cirrus clouds. Overall we can show a considerable improvement in the forecast quality of clouds and radiation.
Michail Mytilinaios, Sara Basart, Sergio Ciamprone, Juan Cuesta, Claudio Dema, Enza Di Tomaso, Paola Formenti, Antonis Gkikas, Oriol Jorba, Ralph Kahn, Carlos Pérez García-Pando, Serena Trippetta, and Lucia Mona
Atmos. Chem. Phys., 23, 5487–5516, https://doi.org/10.5194/acp-23-5487-2023, https://doi.org/10.5194/acp-23-5487-2023, 2023
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Multiscale Online Non-hydrostatic AtmospheRe CHemistry model (MONARCH) dust reanalysis provides a high-resolution 3D reconstruction of past dust conditions, allowing better quantification of climate and socioeconomic dust impacts. We assess the performance of the reanalysis needed to reproduce dust optical depth using dust-related products retrieved from satellite and ground-based observations and show that it reproduces the spatial distribution and seasonal variability of atmospheric dust well.
Patrick Ludwig, Florian Ehmele, Mário J. Franca, Susanna Mohr, Alberto Caldas-Alvarez, James E. Daniell, Uwe Ehret, Hendrik Feldmann, Marie Hundhausen, Peter Knippertz, Katharina Küpfer, Michael Kunz, Bernhard Mühr, Joaquim G. Pinto, Julian Quinting, Andreas M. Schäfer, Frank Seidel, and Christina Wisotzky
Nat. Hazards Earth Syst. Sci., 23, 1287–1311, https://doi.org/10.5194/nhess-23-1287-2023, https://doi.org/10.5194/nhess-23-1287-2023, 2023
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Heavy precipitation in July 2021 led to widespread floods in western Germany and neighboring countries. The event was among the five heaviest precipitation events of the past 70 years in Germany, and the river discharges exceeded by far the statistical 100-year return values. Simulations of the event under future climate conditions revealed a strong and non-linear effect on flood peaks: for +2 K global warming, an 18 % increase in rainfall led to a 39 % increase of the flood peak in the Ahr river.
Susanna Mohr, Uwe Ehret, Michael Kunz, Patrick Ludwig, Alberto Caldas-Alvarez, James E. Daniell, Florian Ehmele, Hendrik Feldmann, Mário J. Franca, Christian Gattke, Marie Hundhausen, Peter Knippertz, Katharina Küpfer, Bernhard Mühr, Joaquim G. Pinto, Julian Quinting, Andreas M. Schäfer, Marc Scheibel, Frank Seidel, and Christina Wisotzky
Nat. Hazards Earth Syst. Sci., 23, 525–551, https://doi.org/10.5194/nhess-23-525-2023, https://doi.org/10.5194/nhess-23-525-2023, 2023
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The flood event in July 2021 was one of the most severe disasters in Europe in the last half century. The objective of this two-part study is a multi-disciplinary assessment that examines the complex process interactions in different compartments, from meteorology to hydrological conditions to hydro-morphological processes to impacts on assets and environment. In addition, we address the question of what measures are possible to generate added value to early response management.
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.
Julia Fuchs, Hendrik Andersen, Jan Cermak, Eva Pauli, and Rob Roebeling
Atmos. Meas. Tech., 15, 4257–4270, https://doi.org/10.5194/amt-15-4257-2022, https://doi.org/10.5194/amt-15-4257-2022, 2022
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Two cloud-masking approaches, a local and a regional approach, using high-resolution satellite data are developed and validated for the region of Paris to improve applicability for analyses of urban effects on low clouds. We found that cloud masks obtained from the regional approach are more appropriate for the high-resolution analysis of locally induced cloud processes. Its applicability is tested for the analysis of typical fog conditions over different surface types.
Caroline Dang, Michal Segal-Rozenhaimer, Haochi Che, Lu Zhang, Paola Formenti, Jonathan Taylor, Amie Dobracki, Sara Purdue, Pui-Shan Wong, Athanasios Nenes, Arthur Sedlacek III, Hugh Coe, Jens Redemann, Paquita Zuidema, Steven Howell, and James Haywood
Atmos. Chem. Phys., 22, 9389–9412, https://doi.org/10.5194/acp-22-9389-2022, https://doi.org/10.5194/acp-22-9389-2022, 2022
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Transmission electron microscopy was used to analyze aged African smoke particles and how the smoke interacts with the marine atmosphere. We found that the volatility of organic aerosol increases with biomass burning plume age, that black carbon is often mixed with potassium salts and that the marine atmosphere can incorporate Na and Cl into smoke particles. Marine salts are more processed when mixed with smoke plumes, and there are interesting Cl-rich yet Na-absent marine particles.
Lu Zhang, Michal Segal-Rozenhaimer, Haochi Che, Caroline Dang, Arthur J. Sedlacek III, Ernie R. Lewis, Amie Dobracki, Jenny P. S. Wong, Paola Formenti, Steven G. Howell, and Athanasios Nenes
Atmos. Chem. Phys., 22, 9199–9213, https://doi.org/10.5194/acp-22-9199-2022, https://doi.org/10.5194/acp-22-9199-2022, 2022
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Widespread biomass burning (BB) events occur annually in Africa and contribute ~ 1 / 3 of global BB emissions, which contain a large family of light-absorbing organics, known as brown carbon (BrC), whose absorption of incident radiation is difficult to estimate, leading to large uncertainties in the global radiative forcing estimation. This study quantifies the BrC absorption of aged BB particles and highlights the potential presence of absorbing iron oxides in this climatically important region.
Enza Di Tomaso, Jerónimo Escribano, Sara Basart, Paul Ginoux, Francesca Macchia, Francesca Barnaba, Francesco Benincasa, Pierre-Antoine Bretonnière, Arnau Buñuel, Miguel Castrillo, Emilio Cuevas, Paola Formenti, María Gonçalves, Oriol Jorba, Martina Klose, Lucia Mona, Gilbert Montané Pinto, Michail Mytilinaios, Vincenzo Obiso, Miriam Olid, Nick Schutgens, Athanasios Votsis, Ernest Werner, and Carlos Pérez García-Pando
Earth Syst. Sci. Data, 14, 2785–2816, https://doi.org/10.5194/essd-14-2785-2022, https://doi.org/10.5194/essd-14-2785-2022, 2022
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MONARCH reanalysis of desert dust aerosols extends the existing observation-based information for mineral dust monitoring by providing 3-hourly upper-air, surface and total column key geophysical variables of the dust cycle over Northern Africa, the Middle East and Europe, at a 0.1° horizontal resolution in a rotated grid, from 2007 to 2016. This work provides evidence of the high accuracy of this data set and its suitability for air quality and health and climate service applications.
Cyrille Flamant, Marco Gaetani, Jean-Pierre Chaboureau, Patrick Chazette, Juan Cuesta, Stuart John Piketh, and Paola Formenti
Atmos. Chem. Phys., 22, 5701–5724, https://doi.org/10.5194/acp-22-5701-2022, https://doi.org/10.5194/acp-22-5701-2022, 2022
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Rivers of smoke extend from tropical southern Africa towards the Indian Ocean during the winter fire season, controlled by the interaction of tropical easterly waves, and westerly waves at mid latitudes. During the AEROCLO-sA field campaign in 2017, a river of smoke was directly observed over Namibia. In this paper, the evolution and atmospheric drivers of the river of smoke are described, and the role of a mid-latitude cut-off low in lifting the smoke to the upper troposphere is highlighted.
Babak Jahani, Hendrik Andersen, Josep Calbó, Josep-Abel González, and Jan Cermak
Atmos. Chem. Phys., 22, 1483–1494, https://doi.org/10.5194/acp-22-1483-2022, https://doi.org/10.5194/acp-22-1483-2022, 2022
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The change in the state of sky from cloudy to cloudless (or vice versa) comprises an additional phase called
transition zonewith characteristics laying between those of aerosols and clouds. This study presents an approach for the quantification of the broadband longwave radiative effects of the cloud–aerosol transition zone at the top of the atmosphere during daytime over the ocean based on satellite observations and radiative transfer simulations.
Julian F. Quinting and Christian M. Grams
Geosci. Model Dev., 15, 715–730, https://doi.org/10.5194/gmd-15-715-2022, https://doi.org/10.5194/gmd-15-715-2022, 2022
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Physical processes in weather systems importantly affect the midlatitude large-scale circulation. This study introduces an artificial-intelligence-based framework which allows the identification of an important weather system – the so-called warm conveyor belt (WCB) – at comparably low computational costs and from data at low spatial and temporal resolution. The framework thus newly enables the systematic investigation of WCBs in large data sets such as climate model projections.
Julian F. Quinting, Christian M. Grams, Annika Oertel, and Moritz Pickl
Geosci. Model Dev., 15, 731–744, https://doi.org/10.5194/gmd-15-731-2022, https://doi.org/10.5194/gmd-15-731-2022, 2022
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This study applies novel artificial-intelligence-based models that allow the identification of one specific weather system which affects the midlatitude circulation. We show that the models yield similar results as their trajectory-based counterpart, which requires data at higher spatiotemporal resolution and is computationally more expensive. Overall, we aim to show how deep learning methods can be used efficiently to support process understanding of biases in weather prediction models.
Matthew W. Christensen, Andrew Gettelman, Jan Cermak, Guy Dagan, Michael Diamond, Alyson Douglas, Graham Feingold, Franziska Glassmeier, Tom Goren, Daniel P. Grosvenor, Edward Gryspeerdt, Ralph Kahn, Zhanqing Li, Po-Lun Ma, Florent Malavelle, Isabel L. McCoy, Daniel T. McCoy, Greg McFarquhar, Johannes Mülmenstädt, Sandip Pal, Anna Possner, Adam Povey, Johannes Quaas, Daniel Rosenfeld, Anja Schmidt, Roland Schrödner, Armin Sorooshian, Philip Stier, Velle Toll, Duncan Watson-Parris, Robert Wood, Mingxi Yang, and Tianle Yuan
Atmos. Chem. Phys., 22, 641–674, https://doi.org/10.5194/acp-22-641-2022, https://doi.org/10.5194/acp-22-641-2022, 2022
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Trace gases and aerosols (tiny airborne particles) are released from a variety of point sources around the globe. Examples include volcanoes, industrial chimneys, forest fires, and ship stacks. These sources provide opportunistic experiments with which to quantify the role of aerosols in modifying cloud properties. We review the current state of understanding on the influence of aerosol on climate built from the wide range of natural and anthropogenic laboratories investigated in recent decades.
Paola Formenti, Claudia Di Biagio, Yue Huang, Jasper Kok, Marc Daniel Mallet, Damien Boulanger, and Mathieu Cazaunau
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2021-403, https://doi.org/10.5194/amt-2021-403, 2021
Publication in AMT not foreseen
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This paper provides with standardized correction factors for the measurements of the most common instruments used in the atmosphere to measure the concentration per size of aerosol particles. These correction factors are provided to users with supplementary information for their use.
Marco Gaetani, Benjamin Pohl, Maria del Carmen Alvarez Castro, Cyrille Flamant, and Paola Formenti
Atmos. Chem. Phys., 21, 16575–16591, https://doi.org/10.5194/acp-21-16575-2021, https://doi.org/10.5194/acp-21-16575-2021, 2021
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During the dry austral winter, biomass fires in tropical Africa emit large amounts of smoke in the atmosphere, with large impacts on climate and air quality. The study of the relationship between atmospheric circulation and smoke transport shows that midlatitude atmospheric disturbances may deflect the smoke from tropical Africa towards southern Africa. Understanding the distribution of the smoke in the region is crucial for climate modelling and air quality monitoring.
Isabelle Chiapello, Paola Formenti, Lydie Mbemba Kabuiku, Fabrice Ducos, Didier Tanré, and François Dulac
Atmos. Chem. Phys., 21, 12715–12737, https://doi.org/10.5194/acp-21-12715-2021, https://doi.org/10.5194/acp-21-12715-2021, 2021
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The Mediterranean atmosphere is impacted by a variety of particle pollution, which exerts a complex pressure on climate and air quality. We analyze the 2005–2013 POLDER-3 satellite advanced aerosol data set over the Western Mediterranean Sea. Aerosols' spatial distribution and temporal evolution suggests a large-scale improvement of air quality related to the fine aerosol component, most probably resulting from reduction of anthropogenic particle emissions in the surrounding European countries.
Danitza Klopper, Stuart J. Piketh, Roelof Burger, Simon Dirkse, and Paola Formenti
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2021-668, https://doi.org/10.5194/acp-2021-668, 2021
Revised manuscript not accepted
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The western coast of southern Africa is a key region of the Earth, with persistent clouds and particles also transported from distant forest fires. The atmosphere is stratified as a result of the different temperatures of the cold Atlantic ocean and the warm semi-arid land, and that affects how the particles will be distributed whilst in the atmosphere and how long they will persist. We used long term satellite and in situ observations to describe, for the first time, those main features.
Aurélien Chauvigné, Fabien Waquet, Frédérique Auriol, Luc Blarel, Cyril Delegove, Oleg Dubovik, Cyrille Flamant, Marco Gaetani, Philippe Goloub, Rodrigue Loisil, Marc Mallet, Jean-Marc Nicolas, Frédéric Parol, Fanny Peers, Benjamin Torres, and Paola Formenti
Atmos. Chem. Phys., 21, 8233–8253, https://doi.org/10.5194/acp-21-8233-2021, https://doi.org/10.5194/acp-21-8233-2021, 2021
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This work presents aerosol above-cloud properties close to the Namibian coast from a combination of airborne passive remote sensing. The complete analysis of aerosol and cloud optical properties and their microphysical and radiative properties allows us to better identify the impacts of biomass burning emissions. This work also gives a complete overview of the key parameters for constraining climate models in case aerosol and cloud coexist in the troposphere.
Roland Stirnberg, Jan Cermak, Simone Kotthaus, Martial Haeffelin, Hendrik Andersen, Julia Fuchs, Miae Kim, Jean-Eudes Petit, and Olivier Favez
Atmos. Chem. Phys., 21, 3919–3948, https://doi.org/10.5194/acp-21-3919-2021, https://doi.org/10.5194/acp-21-3919-2021, 2021
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Air pollution endangers human health and poses a problem particularly in densely populated areas. Here, an explainable machine learning approach is used to analyse periods of high particle concentrations for a suburban site southwest of Paris to better understand its atmospheric drivers. Air pollution is particularly excaberated by low temperatures and low mixed layer heights, but processes vary substantially between and within seasons.
Jens Redemann, Robert Wood, Paquita Zuidema, Sarah J. Doherty, Bernadette Luna, Samuel E. LeBlanc, Michael S. Diamond, Yohei Shinozuka, Ian Y. Chang, Rei Ueyama, Leonhard Pfister, Ju-Mee Ryoo, Amie N. Dobracki, Arlindo M. da Silva, Karla M. Longo, Meloë S. Kacenelenbogen, Connor J. Flynn, Kristina Pistone, Nichola M. Knox, Stuart J. Piketh, James M. Haywood, Paola Formenti, Marc Mallet, Philip Stier, Andrew S. Ackerman, Susanne E. Bauer, Ann M. Fridlind, Gregory R. Carmichael, Pablo E. Saide, Gonzalo A. Ferrada, Steven G. Howell, Steffen Freitag, Brian Cairns, Brent N. Holben, Kirk D. Knobelspiesse, Simone Tanelli, Tristan S. L'Ecuyer, Andrew M. Dzambo, Ousmane O. Sy, Greg M. McFarquhar, Michael R. Poellot, Siddhant Gupta, Joseph R. O'Brien, Athanasios Nenes, Mary Kacarab, Jenny P. S. Wong, Jennifer D. Small-Griswold, Kenneth L. Thornhill, David Noone, James R. Podolske, K. Sebastian Schmidt, Peter Pilewskie, Hong Chen, Sabrina P. Cochrane, Arthur J. Sedlacek, Timothy J. Lang, Eric Stith, Michal Segal-Rozenhaimer, Richard A. Ferrare, Sharon P. Burton, Chris A. Hostetler, David J. Diner, Felix C. Seidel, Steven E. Platnick, Jeffrey S. Myers, Kerry G. Meyer, Douglas A. Spangenberg, Hal Maring, and Lan Gao
Atmos. Chem. Phys., 21, 1507–1563, https://doi.org/10.5194/acp-21-1507-2021, https://doi.org/10.5194/acp-21-1507-2021, 2021
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Southern Africa produces significant biomass burning emissions whose impacts on regional and global climate are poorly understood. ORACLES (ObseRvations of Aerosols above CLouds and their intEractionS) is a 5-year NASA investigation designed to study the key processes that determine these climate impacts. The main purpose of this paper is to familiarize the broader scientific community with the ORACLES project, the dataset it produced, and the most important initial findings.
Assaf Hochman, Sebastian Scher, Julian Quinting, Joaquim G. Pinto, and Gabriele Messori
Earth Syst. Dynam., 12, 133–149, https://doi.org/10.5194/esd-12-133-2021, https://doi.org/10.5194/esd-12-133-2021, 2021
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Skillful forecasts of extreme weather events have a major socioeconomic relevance. Here, we compare two approaches to diagnose the predictability of eastern Mediterranean heat waves: one based on recent developments in dynamical systems theory and one leveraging numerical ensemble weather forecasts. We conclude that the former can be a useful and cost-efficient complement to conventional numerical forecasts for understanding the dynamics of eastern Mediterranean heat waves.
Jim M. Haywood, Steven J. Abel, Paul A. Barrett, Nicolas Bellouin, Alan Blyth, Keith N. Bower, Melissa Brooks, Ken Carslaw, Haochi Che, Hugh Coe, Michael I. Cotterell, Ian Crawford, Zhiqiang Cui, Nicholas Davies, Beth Dingley, Paul Field, Paola Formenti, Hamish Gordon, Martin de Graaf, Ross Herbert, Ben Johnson, Anthony C. Jones, Justin M. Langridge, Florent Malavelle, Daniel G. Partridge, Fanny Peers, Jens Redemann, Philip Stier, Kate Szpek, Jonathan W. Taylor, Duncan Watson-Parris, Robert Wood, Huihui Wu, and Paquita Zuidema
Atmos. Chem. Phys., 21, 1049–1084, https://doi.org/10.5194/acp-21-1049-2021, https://doi.org/10.5194/acp-21-1049-2021, 2021
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Every year, the seasonal cycle of biomass burning from agricultural practices in Africa creates a huge plume of smoke that travels many thousands of kilometres over the Atlantic Ocean. This study provides an overview of a measurement campaign called the cloud–aerosol–radiation interaction and forcing for year 2017 (CLARIFY-2017) and documents the rationale, deployment strategy, observations, and key results from the campaign which utilized the heavily equipped FAAM atmospheric research aircraft.
Danitza Klopper, Paola Formenti, Andreas Namwoonde, Mathieu Cazaunau, Servanne Chevaillier, Anaïs Feron, Cécile Gaimoz, Patrick Hease, Fadi Lahmidi, Cécile Mirande-Bret, Sylvain Triquet, Zirui Zeng, and Stuart J. Piketh
Atmos. Chem. Phys., 20, 15811–15833, https://doi.org/10.5194/acp-20-15811-2020, https://doi.org/10.5194/acp-20-15811-2020, 2020
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The chemical composition of aerosol particles is very important as it determines to which extent they can affect the Earth's climate by acting with solar light and modifying the properties of clouds. The South Atlantic region is a remote and under-explored region to date where these effects could be important. The measurements presented in this paper consist in the analysis of samples collected at a coastal site in Namibia. The first long-term source apportionment is presented and discussed.
Clarissa Baldo, Paola Formenti, Sophie Nowak, Servanne Chevaillier, Mathieu Cazaunau, Edouard Pangui, Claudia Di Biagio, Jean-Francois Doussin, Konstantin Ignatyev, Pavla Dagsson-Waldhauserova, Olafur Arnalds, A. Robert MacKenzie, and Zongbo Shi
Atmos. Chem. Phys., 20, 13521–13539, https://doi.org/10.5194/acp-20-13521-2020, https://doi.org/10.5194/acp-20-13521-2020, 2020
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We showed that Icelandic dust has a fundamentally different chemical and mineralogical composition from low-latitude dust. In particular, magnetite is as high as 1 %–2 % of the total dust mass. Our results suggest that Icelandic dust may have an important impact on the radiation balance in the subpolar and polar regions.
Marc Mallet, Fabien Solmon, Pierre Nabat, Nellie Elguindi, Fabien Waquet, Dominique Bouniol, Andrew Mark Sayer, Kerry Meyer, Romain Roehrig, Martine Michou, Paquita Zuidema, Cyrille Flamant, Jens Redemann, and Paola Formenti
Atmos. Chem. Phys., 20, 13191–13216, https://doi.org/10.5194/acp-20-13191-2020, https://doi.org/10.5194/acp-20-13191-2020, 2020
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This paper presents numerical simulations using two regional climate models to study the impact of biomass fire plumes from central Africa on the radiative balance of this region. The results indicate that biomass fires can either warm the regional climate when they are located above low clouds or cool it when they are located above land. They can also alter sea and land surface temperatures by decreasing solar radiation at the surface. Finally, they can also modify the atmospheric dynamics.
David O. De Haan, Lelia N. Hawkins, Kevin Jansen, Hannah G. Welsh, Raunak Pednekar, Alexia de Loera, Natalie G. Jimenez, Margaret A. Tolbert, Mathieu Cazaunau, Aline Gratien, Antonin Bergé, Edouard Pangui, Paola Formenti, and Jean-François Doussin
Atmos. Chem. Phys., 20, 9581–9590, https://doi.org/10.5194/acp-20-9581-2020, https://doi.org/10.5194/acp-20-9581-2020, 2020
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When exposed to glyoxal in chamber experiments, dry ammonium or methylammonium sulfate particles turn brown immediately and reversibly without increasing in size. Much less browning was observed on wet aerosol particles, and no browning was observed with sodium sulfate aerosol. While estimated dry aerosol light absorption caused by background glyoxal (70 ppt) is insignificant compared to that of secondary brown carbon overall, in polluted regions this process could be a source of brown carbon.
Susanna Mohr, Jannik Wilhelm, Jan Wandel, Michael Kunz, Raphael Portmann, Heinz Jürgen Punge, Manuel Schmidberger, Julian F. Quinting, and Christian M. Grams
Weather Clim. Dynam., 1, 325–348, https://doi.org/10.5194/wcd-1-325-2020, https://doi.org/10.5194/wcd-1-325-2020, 2020
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We investigated an exceptional thunderstorm episode in 2018, in which atmospheric blocking provided large-scale environmental conditions favouring convection. Furthermore, blocking was accompanied by a high cut-off frequency on its upstream side, which together with filaments of high PV provided the mesoscale setting for deep moist convection. The exceptional persistence of low stability combined with weak wind speed in the mid-troposphere over more than 3 weeks has never been observed before.
Nelson Bègue, Lerato Shikwambana, Hassan Bencherif, Juan Pallotta, Venkataraman Sivakumar, Elian Wolfram, Nkanyiso Mbatha, Facundo Orte, David Jean Du Preez, Marion Ranaivombola, Stuart Piketh, and Paola Formenti
Ann. Geophys., 38, 395–420, https://doi.org/10.5194/angeo-38-395-2020, https://doi.org/10.5194/angeo-38-395-2020, 2020
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This study investigates the influence of the 2015 Calbuco eruption (41.2°S, 72.4°W; Chile) on the total columnar aerosol optical properties in the Southern Hemisphere. The well-known technique of sun photometry was applied to the investigation of the transport and the spatio-temporal evolution of the optical properties of the volcanic plume. The CIMEL sun photometer measurements performed over six South American and three African sites were statistically analyzed.
Hendrik Andersen, Jan Cermak, Julia Fuchs, Peter Knippertz, Marco Gaetani, Julian Quinting, Sebastian Sippel, and Roland Vogt
Atmos. Chem. Phys., 20, 3415–3438, https://doi.org/10.5194/acp-20-3415-2020, https://doi.org/10.5194/acp-20-3415-2020, 2020
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Fog and low clouds (FLCs) are an essential but poorly understood element of Namib regional climate. Here, a satellite-based data set of FLCs in central Namib, reanalysis data, and back trajectories are used to systematically analyze conditions when FLCs occur. Synoptic-scale mechanisms are identified that influence the formation of FLCs and the onshore advection of marine boundary-layer air masses. The findings lead to a new conceptual model of mechanisms that drive FLC variability in the Namib.
Samuel E. LeBlanc, Jens Redemann, Connor Flynn, Kristina Pistone, Meloë Kacenelenbogen, Michal Segal-Rosenheimer, Yohei Shinozuka, Stephen Dunagan, Robert P. Dahlgren, Kerry Meyer, James Podolske, Steven G. Howell, Steffen Freitag, Jennifer Small-Griswold, Brent Holben, Michael Diamond, Robert Wood, Paola Formenti, Stuart Piketh, Gillian Maggs-Kölling, Monja Gerber, and Andreas Namwoonde
Atmos. Chem. Phys., 20, 1565–1590, https://doi.org/10.5194/acp-20-1565-2020, https://doi.org/10.5194/acp-20-1565-2020, 2020
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The southeast Atlantic during August–October experiences layers of smoke from biomass burning over marine stratocumulus clouds. Here we present the light attenuation of the smoke and its dependence in the spatial, vertical, and spectral domain through direct measurements from an airborne platform during September 2016. From our observations of this climatically important smoke, we found an average aerosol optical depth of 0.32 at 500 nm, slightly lower than comparative satellite measurements.
Claudia Di Biagio, Paola Formenti, Yves Balkanski, Lorenzo Caponi, Mathieu Cazaunau, Edouard Pangui, Emilie Journet, Sophie Nowak, Meinrat O. Andreae, Konrad Kandler, Thuraya Saeed, Stuart Piketh, David Seibert, Earle Williams, and Jean-François Doussin
Atmos. Chem. Phys., 19, 15503–15531, https://doi.org/10.5194/acp-19-15503-2019, https://doi.org/10.5194/acp-19-15503-2019, 2019
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This paper presents a new dataset of laboratory measurements of the shortwave (SW) spectral complex refractive index and single-scattering albedo (SSA) for global mineral dust aerosols of varying origin and composition. Our results show that the dust refractive index and SSA vary strongly from source to source, mostly due to particle iron content changes. We recommend that source-dependent values of the SW spectral refractive index and SSA be used in models and remote sensing applications.
Patrick Chazette, Cyrille Flamant, Julien Totems, Marco Gaetani, Gwendoline Smith, Alexandre Baron, Xavier Landsheere, Karine Desboeufs, Jean-François Doussin, and Paola Formenti
Atmos. Chem. Phys., 19, 14979–15005, https://doi.org/10.5194/acp-19-14979-2019, https://doi.org/10.5194/acp-19-14979-2019, 2019
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Evolution of the vertical distribution and optical properties of aerosols in the free troposphere is analysed for the first time over the Namibian coast, a region where uncertainties on aerosol–cloud coupling in climate simulations are significant. The high variability of atmospheric aerosol composition is highlighted using a combination of ground-based, airborne and space-borne lidar. Aerosols are mainly transported from Angola, but part of the highest aerosol layer may come from South America.
Karmen Babić, Norbert Kalthoff, Bianca Adler, Julian F. Quinting, Fabienne Lohou, Cheikh Dione, and Marie Lothon
Atmos. Chem. Phys., 19, 13489–13506, https://doi.org/10.5194/acp-19-13489-2019, https://doi.org/10.5194/acp-19-13489-2019, 2019
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This study investigates differences in atmospheric conditions between nights with and without low-level stratus clouds (LLCs) over southern West Africa. We use high-quality observations collected during 2016 summer monsoon season and the ERA5 reanalysis data set. Our results show that the formation of LLCs depends on the interplay between the onset time and strength of the nocturnal low-level jet, horizontal cold-air advection, and the overall moisture level in the whole region.
Marc D. Mallet, Barbara D'Anna, Aurélie Même, Maria Chiara Bove, Federico Cassola, Giandomenico Pace, Karine Desboeufs, Claudia Di Biagio, Jean-Francois Doussin, Michel Maille, Dario Massabò, Jean Sciare, Pascal Zapf, Alcide Giorgio di Sarra, and Paola Formenti
Atmos. Chem. Phys., 19, 11123–11142, https://doi.org/10.5194/acp-19-11123-2019, https://doi.org/10.5194/acp-19-11123-2019, 2019
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We present findings from a summertime field campaign at the remote island of Lampedusa in the central Mediterranean Sea. We show that the aerosol loading is similar to coastal sites around the Mediterranean. We observe higher loadings of sulfate and aged organic aerosol from air masses transported over the central and eastern Mediterranean in comparison to those from the western Mediterranean. These results highlight the rarity of pristine air masses, even in remote marine environments.
Marc Mallet, Pierre Nabat, Paquita Zuidema, Jens Redemann, Andrew Mark Sayer, Martin Stengel, Sebastian Schmidt, Sabrina Cochrane, Sharon Burton, Richard Ferrare, Kerry Meyer, Pablo Saide, Hiren Jethva, Omar Torres, Robert Wood, David Saint Martin, Romain Roehrig, Christina Hsu, and Paola Formenti
Atmos. Chem. Phys., 19, 4963–4990, https://doi.org/10.5194/acp-19-4963-2019, https://doi.org/10.5194/acp-19-4963-2019, 2019
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The model is able to represent LWP but not the LCF. AOD is consistent over the continent but also over ocean (ACAOD). Differences are observed in SSA due to the absence of internal mixing in ALADIN-Climate. A significant regional gradient of the forcing at TOA is observed. An intense positive forcing is simulated over Gabon. Results highlight the significant effect of enhanced moisture on BBA extinction. The surface dimming modifies the energy budget.
Hendrik Andersen, Jan Cermak, Irina Solodovnik, Luca Lelli, and Roland Vogt
Atmos. Chem. Phys., 19, 4383–4392, https://doi.org/10.5194/acp-19-4383-2019, https://doi.org/10.5194/acp-19-4383-2019, 2019
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Fog and low clouds (FLCs) are an essential but poorly understood component of Namib-region climate. This study uses observations from multiple satellite platforms and ground-based measurements to coherently characterize Namib-region FLC patterns. Findings concerning the seasonal cycle of the vertical structure and the diurnal cycle of FLCs lead to a new conceptual model of the spatiotemporal dynamics of FLCs in the Namib and help to improve the understanding of underlying processes.
Karmen Babić, Bianca Adler, Norbert Kalthoff, Hendrik Andersen, Cheikh Dione, Fabienne Lohou, Marie Lothon, and Xabier Pedruzo-Bagazgoitia
Atmos. Chem. Phys., 19, 1281–1299, https://doi.org/10.5194/acp-19-1281-2019, https://doi.org/10.5194/acp-19-1281-2019, 2019
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The first detailed observational analysis of the complete diurnal cycle of low-level clouds (LLC) and associated atmospheric processes over southern West Africa is performed using the data gathered within the DACCIWA (Dynamics-Aerosol-Chemistry-Cloud-Interactions in West Africa) ground-based campaign. We find cooling related to the horizontal advection, which occurs in connection with the inflow of cool maritime air mass and a prominent low-level jet, to have the dominant role in LLC formation.
Matthias Wiegner, Ina Mattis, Margit Pattantyús-Ábrahám, Juan Antonio Bravo-Aranda, Yann Poltera, Alexander Haefele, Maxime Hervo, Ulrich Görsdorf, Ronny Leinweber, Josef Gasteiger, Martial Haeffelin, Frank Wagner, Jan Cermak, Katerina Komínková, Mike Brettle, Christoph Münkel, and Kornelia Pönitz
Atmos. Meas. Tech., 12, 471–490, https://doi.org/10.5194/amt-12-471-2019, https://doi.org/10.5194/amt-12-471-2019, 2019
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Many ceilometers are influenced by water vapor absorption in the spectral range around 910 nm. Thus, a correction is required to retrieve aerosol optical properties. Validation of this correction scheme was performed in the framework of CeiLinEx2015 for several ceilometers with good agreement for Vaisala's CL51 ceilometer. For future applications we recommend monitoring the emitted wavelength and providing
darkmeasurements on a regular basis to be able to correct for signal artifacts.
Bianca Adler, Karmen Babić, Norbert Kalthoff, Fabienne Lohou, Marie Lothon, Cheikh Dione, Xabier Pedruzo-Bagazgoitia, and Hendrik Andersen
Atmos. Chem. Phys., 19, 663–681, https://doi.org/10.5194/acp-19-663-2019, https://doi.org/10.5194/acp-19-663-2019, 2019
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This study deals with nocturnal stratiform low-level clouds that frequently form in the atmospheric boundary layer over southern West Africa. We use observational data from 11 nights to characterize the clouds and intranight variability of boundary layer conditions as well as to assess the physical processes relevant for cloud formation. We find that cooling is crucial to reach saturation and a large part of the cooling is related to horizontal advection of cool air from the Gulf of Guinea.
María José Granados-Muñoz, Michael Sicard, Roberto Román, Jose Antonio Benavent-Oltra, Rubén Barragán, Gerard Brogniez, Cyrielle Denjean, Marc Mallet, Paola Formenti, Benjamín Torres, and Lucas Alados-Arboledas
Atmos. Chem. Phys., 19, 523–542, https://doi.org/10.5194/acp-19-523-2019, https://doi.org/10.5194/acp-19-523-2019, 2019
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The influence of mineral dust in the direct radiative effect is affected by a large uncertainty. This study investigates mineral dust radiative properties during an episode affecting southern Spain in June 2013 by using remote sensors and data collected on board an aircraft to feed a radiative transfer model. The study reveals the complexity of parameterizing these models, as characterizing mineral dust is still quite challenging, and the need for accurate mineral dust measurements.
Paola Formenti, Lydie Mbemba Kabuiku, Isabelle Chiapello, Fabrice Ducos, François Dulac, and Didier Tanré
Atmos. Meas. Tech., 11, 6761–6784, https://doi.org/10.5194/amt-11-6761-2018, https://doi.org/10.5194/amt-11-6761-2018, 2018
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Aerosol particles from natural and anthropogenic sources are climate regulators as they can counteract or amplify the warming effect of greenhouse gases, but are difficult to observe due to their temporal and spatial variability. Satellite sensors can provide the needed global coverage but need validation. In this paper we explore the capability of the POLDER-3 advanced space-borne sensor to observe aerosols over the western Mediterranean region.
Claire L. Ryder, Franco Marenco, Jennifer K. Brooke, Victor Estelles, Richard Cotton, Paola Formenti, James B. McQuaid, Hannah C. Price, Dantong Liu, Patrick Ausset, Phil D. Rosenberg, Jonathan W. Taylor, Tom Choularton, Keith Bower, Hugh Coe, Martin Gallagher, Jonathan Crosier, Gary Lloyd, Eleanor J. Highwood, and Benjamin J. Murray
Atmos. Chem. Phys., 18, 17225–17257, https://doi.org/10.5194/acp-18-17225-2018, https://doi.org/10.5194/acp-18-17225-2018, 2018
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Every year, millions of tons of Saharan dust particles are carried across the Atlantic by the wind, where they can affect weather patterns and climate. Their sizes span orders of magnitude, but the largest (over 10 microns – around the width of a human hair) are difficult to measure and few observations exist. Here we show new aircraft observations of large dust particles, finding more than we would expect, and we quantify their properties which allow them to interact with atmospheric radiation.
Paola Formenti, Stuart John Piketh, Andreas Namwoonde, Danitza Klopper, Roelof Burger, Mathieu Cazaunau, Anaïs Feron, Cécile Gaimoz, Stephen Broccardo, Nicola Walton, Karine Desboeufs, Guillaume Siour, Mattheus Hanghome, Samuel Mafwila, Edosa Omoregie, Wolfgang Junkermann, and Willy Maenhaut
Atmos. Chem. Phys., 18, 17003–17016, https://doi.org/10.5194/acp-18-17003-2018, https://doi.org/10.5194/acp-18-17003-2018, 2018
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Three-years of continuous measurements at the Henties Bay Aerosol Observatory (HBAO; 22°S, 14°05’E), Namibia, show that during the austral wintertime, long- and medium-range transport of pollution from biomass and fossil fuel burning give rise to peaks of light-absorbing black carbon aerosols into the marine boundary layer ahead of the main biomass burning season. This could affect the cloud properties.
Julia Fuchs, Jan Cermak, and Hendrik Andersen
Atmos. Chem. Phys., 18, 16537–16552, https://doi.org/10.5194/acp-18-16537-2018, https://doi.org/10.5194/acp-18-16537-2018, 2018
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This study separates the influence of aerosol on cloud properties in the southeast Atlantic region from meteorological conditions in the biomass-burning season. Machine learning is used to link 8-day-averaged satellite and reanalysis data sets. Distinct regimes of aerosol–cloud interactions are identified in the subregions of the southeast Atlantic based on the obtained sensitivities.
Dario Massabò, Silvia Giulia Danelli, Paolo Brotto, Antonio Comite, Camilla Costa, Andrea Di Cesare, Jean François Doussin, Federico Ferraro, Paola Formenti, Elena Gatta, Laura Negretti, Maddalena Oliva, Franco Parodi, Luigi Vezzulli, and Paolo Prati
Atmos. Meas. Tech., 11, 5885–5900, https://doi.org/10.5194/amt-11-5885-2018, https://doi.org/10.5194/amt-11-5885-2018, 2018
Hendrik Andersen and Jan Cermak
Atmos. Meas. Tech., 11, 5461–5470, https://doi.org/10.5194/amt-11-5461-2018, https://doi.org/10.5194/amt-11-5461-2018, 2018
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Fog and low clouds (FLCs) are a valuable source of water for many ecosystems in the Namib. This study presents the first fully diurnal satellite detection of FLCs, revealing the spatial and temporal patterns in the Namib. A validation is conducted against station measurements in the central Namib and shows a high overall accuracy. The average timing and persistence of FLCs seem to depend on the distance to the coast, suggesting that the region is dominated by advection-driven FLCs.
Daniela Meloni, Alcide di Sarra, Gérard Brogniez, Cyrielle Denjean, Lorenzo De Silvestri, Tatiana Di Iorio, Paola Formenti, José L. Gómez-Amo, Julian Gröbner, Natalia Kouremeti, Giuliano Liuzzi, Marc Mallet, Giandomenico Pace, and Damiano M. Sferlazzo
Atmos. Chem. Phys., 18, 4377–4401, https://doi.org/10.5194/acp-18-4377-2018, https://doi.org/10.5194/acp-18-4377-2018, 2018
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This study examines how different aerosol optical properties determine the dust longwave radiative effects at the surface, in the atmosphere and at the top of the atmosphere, based on the combination of remote sensing and in situ observations from the ground, from airborne sensors, and from space, by means of radiative transfer modelling. The closure experiment is based on longwave irradiances and spectral brightness temperatures measured during the 2013 ChArMEx–ADRIMED campaign at Lampedusa.
Claudia Di Biagio, Paola Formenti, Mathieu Cazaunau, Edouard Pangui, Nicolas Marchand, and Jean-François Doussin
Atmos. Meas. Tech., 10, 2923–2939, https://doi.org/10.5194/amt-10-2923-2017, https://doi.org/10.5194/amt-10-2923-2017, 2017
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Mineral dust is one of the most abundant aerosol species at the global scale and an accurate estimation of its absorption at solar wavelengths is crucial to assess its impact on climate. In this work we provide an estimate of the Aethalometer multiple scattering correction for mineral dust aerosols at 450 and 660 nm. Our results suggest that the use of an optimized correction factor can lead to up to 11 % higher absorption coefficient and to 3 % higher single scattering albedo for mineral dust.
Hendrik Andersen, Jan Cermak, Julia Fuchs, Reto Knutti, and Ulrike Lohmann
Atmos. Chem. Phys., 17, 9535–9546, https://doi.org/10.5194/acp-17-9535-2017, https://doi.org/10.5194/acp-17-9535-2017, 2017
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Aerosol-cloud interactions continue to contribute large uncertainties to our climate system understanding. In this study, we use near-global satellite and reanalysis data sets to predict marine liquid-water clouds by means of artificial neural networks. We show that on the system scale, lower-tropospheric stability and boundary layer height are the main determinants of liquid-water clouds. Aerosols show the expected impact on clouds but are less relevant than some meteorological factors.
Lorenzo Caponi, Paola Formenti, Dario Massabó, Claudia Di Biagio, Mathieu Cazaunau, Edouard Pangui, Servanne Chevaillier, Gautier Landrot, Meinrat O. Andreae, Konrad Kandler, Stuart Piketh, Thuraya Saeed, Dave Seibert, Earle Williams, Yves Balkanski, Paolo Prati, and Jean-François Doussin
Atmos. Chem. Phys., 17, 7175–7191, https://doi.org/10.5194/acp-17-7175-2017, https://doi.org/10.5194/acp-17-7175-2017, 2017
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This paper presents new laboratory measurements of the shortwave mass absorption efficiency (MAE) used by climate models for mineral dust of different origin and at different sizes. We found that small particles are more efficient, by given mass, in absorbing radiation, particularly at shorter wavelength. Because dust has high concentrations in the atmosphere, light absorption by mineral dust can be competitive to other absorbing atmospheric aerosols such as black and brown carbon.
Igor B. Konovalov, Matthias Beekmann, Evgeny V. Berezin, Paola Formenti, and Meinrat O. Andreae
Atmos. Chem. Phys., 17, 4513–4537, https://doi.org/10.5194/acp-17-4513-2017, https://doi.org/10.5194/acp-17-4513-2017, 2017
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A shortage of consistent observational evidence on biomass burning (BB) aerosol aging processes hinders the development of their adequate representations in atmospheric models. Here we show that useful insights into the BB aerosol dynamics can be obtained from analysis of satellite measurements of aerosol optical depth and carbon dioxide. Our results indicate that aging processes strongly affect the evolution of BB aerosol in smoke plumes from wildfires in Siberia.
Giuliano Liuzzi, Guido Masiello, Carmine Serio, Daniela Meloni, Claudia Di Biagio, and Paola Formenti
Atmos. Meas. Tech., 10, 599–615, https://doi.org/10.5194/amt-10-599-2017, https://doi.org/10.5194/amt-10-599-2017, 2017
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In this work we have given a contribution to better understand some of the properties of the desert dust plumes in the western Mediterranean, using both direct measurements and satellite observations. This study has mainly evidenced that satellite observations can provide information about the geographical provenance of dust. This is important because such variability is reflected in the way in which dust interacts with atmosphere and impacts over the observed infrared radiation from satellites.
Claudia Di Biagio, Paola Formenti, Yves Balkanski, Lorenzo Caponi, Mathieu Cazaunau, Edouard Pangui, Emilie Journet, Sophie Nowak, Sandrine Caquineau, Meinrat O. Andreae, Konrad Kandler, Thuraya Saeed, Stuart Piketh, David Seibert, Earle Williams, and Jean-François Doussin
Atmos. Chem. Phys., 17, 1901–1929, https://doi.org/10.5194/acp-17-1901-2017, https://doi.org/10.5194/acp-17-1901-2017, 2017
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Modeling the interaction of dust with long-wave (LW) radiation is still a challenge due to the scarcity of information on their refractive index. In this paper, we present a unique dataset of dust refractive indices obtained from in situ measurements in a large smog chamber. Our results show that the dust LW refractive index varies strongly from source to source due to particle composition changes. We recommend taking this variability into account in climate and remote sensing applications.
Claudia Di Biagio, Paola Formenti, Lionel Doppler, Cécile Gaimoz, Noel Grand, Gerard Ancellet, Jean-Luc Attié, Silvia Bucci, Philippe Dubuisson, Federico Fierli, Marc Mallet, and François Ravetta
Atmos. Chem. Phys., 16, 10591–10607, https://doi.org/10.5194/acp-16-10591-2016, https://doi.org/10.5194/acp-16-10591-2016, 2016
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Pollution aerosols strongly influence the composition of the Western Mediterranean, but at present little is known on their optical properties. Here, we report observations of pollution aerosols measured during the TRAQA airborne campaign in summer 2012. Data from this study indicate a large variability of the absorption for pollution particles. This variability strongly influences their direct radiative effect, with possible consequences on the hydrological cycle in this part of the basin.
S. Mailler, L. Menut, A. G. di Sarra, S. Becagli, T. Di Iorio, B. Bessagnet, R. Briant, P. Formenti, J.-F. Doussin, J. L. Gómez-Amo, M. Mallet, G. Rea, G. Siour, D. M. Sferlazzo, R. Traversi, R. Udisti, and S. Turquety
Atmos. Chem. Phys., 16, 1219–1244, https://doi.org/10.5194/acp-16-1219-2016, https://doi.org/10.5194/acp-16-1219-2016, 2016
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We studied the impact of aerosols on tropospheric photolysis rates at Lampedusa during the CharMEx/ADRIMED campaign in June 2013. It is shown by using the CHIMERE chemistry-transport model (CTM) as well as in situ and remote-sensing measurements that taking into account the radiative effect of the tropospheric aerosols improves the ability of the model to reproduce the observed photolysis rates. It is hence important for CTMs to include the radiative effect of aerosols on photochemistry.
C. Denjean, F. Cassola, A. Mazzino, S. Triquet, S. Chevaillier, N. Grand, T. Bourrianne, G. Momboisse, K. Sellegri, A. Schwarzenbock, E. Freney, M. Mallet, and P. Formenti
Atmos. Chem. Phys., 16, 1081–1104, https://doi.org/10.5194/acp-16-1081-2016, https://doi.org/10.5194/acp-16-1081-2016, 2016
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This study investigates the size distribution, chemical composition, and optical properties of Saharan mineral dust transported over the western Mediterranean using in situ measurements collected from aircraft. Their variability due to altitude, time of transport, and mixing rate with pollution particles are discussed. We found moderate light absorption of the dust plumes even in the presence of pollution particles and the persistence of large dust particles after transport in the Mediterranean.
M. Mallet, F. Dulac, P. Formenti, P. Nabat, J. Sciare, G. Roberts, J. Pelon, G. Ancellet, D. Tanré, F. Parol, C. Denjean, G. Brogniez, A. di Sarra, L. Alados-Arboledas, J. Arndt, F. Auriol, L. Blarel, T. Bourrianne, P. Chazette, S. Chevaillier, M. Claeys, B. D'Anna, Y. Derimian, K. Desboeufs, T. Di Iorio, J.-F. Doussin, P. Durand, A. Féron, E. Freney, C. Gaimoz, P. Goloub, J. L. Gómez-Amo, M. J. Granados-Muñoz, N. Grand, E. Hamonou, I. Jankowiak, M. Jeannot, J.-F. Léon, M. Maillé, S. Mailler, D. Meloni, L. Menut, G. Momboisse, J. Nicolas, T. Podvin, V. Pont, G. Rea, J.-B. Renard, L. Roblou, K. Schepanski, A. Schwarzenboeck, K. Sellegri, M. Sicard, F. Solmon, S. Somot, B Torres, J. Totems, S. Triquet, N. Verdier, C. Verwaerde, F. Waquet, J. Wenger, and P. Zapf
Atmos. Chem. Phys., 16, 455–504, https://doi.org/10.5194/acp-16-455-2016, https://doi.org/10.5194/acp-16-455-2016, 2016
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The aim of this article is to present an experimental campaign over the Mediterranean focused on aerosol-radiation measurements and modeling. Results indicate an important atmospheric loading associated with a moderate absorbing ability of mineral dust. Observations suggest a complex vertical structure and size distributions characterized by large aerosols within dust plumes. The radiative effect is highly variable, with negative forcing over the Mediterranean and positive over northern Africa.
C. Di Biagio, L. Doppler, C. Gaimoz, N. Grand, G. Ancellet, J.-C. Raut, M. Beekmann, A. Borbon, K. Sartelet, J.-L. Attié, F. Ravetta, and P. Formenti
Atmos. Chem. Phys., 15, 9611–9630, https://doi.org/10.5194/acp-15-9611-2015, https://doi.org/10.5194/acp-15-9611-2015, 2015
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Observations from this study indicate that continental pollution largely affects the atmospheric composition and structure of the western Mediterranean basin. Pollution plumes reach 3000-4000 m in altitude and present a very complex and highly stratified structure, characterized by fresh and aged layers both in the boundary layer and in the free troposphere. Also we report the observations of high levels of ultrafine particles over the basin, possibly linked to new particle formation events.
C. L. Ryder, J. B. McQuaid, C. Flamant, P. D. Rosenberg, R. Washington, H. E. Brindley, E. J. Highwood, J. H. Marsham, D. J. Parker, M. C. Todd, J. R. Banks, J. K. Brooke, S. Engelstaedter, V. Estelles, P. Formenti, L. Garcia-Carreras, C. Kocha, F. Marenco, H. Sodemann, C. J. T. Allen, A. Bourdon, M. Bart, C. Cavazos-Guerra, S. Chevaillier, J. Crosier, E. Darbyshire, A. R. Dean, J. R. Dorsey, J. Kent, D. O'Sullivan, K. Schepanski, K. Szpek, J. Trembath, and A. Woolley
Atmos. Chem. Phys., 15, 8479–8520, https://doi.org/10.5194/acp-15-8479-2015, https://doi.org/10.5194/acp-15-8479-2015, 2015
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Measurements of the Saharan atmosphere and of atmospheric mineral dust are lacking but are vital to our understanding of the climate of this region and their impacts further afield. Novel observations were made by the Fennec climate programme during June 2011 and 2012 using ground-based, remote sensing and airborne platforms. Here we describe the airborne observations and the contributions they have made to furthering our understanding of the Saharan climate system.
L. Menut, S. Mailler, G. Siour, B. Bessagnet, S. Turquety, G. Rea, R. Briant, M. Mallet, J. Sciare, P. Formenti, and F. Meleux
Atmos. Chem. Phys., 15, 6159–6182, https://doi.org/10.5194/acp-15-6159-2015, https://doi.org/10.5194/acp-15-6159-2015, 2015
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The ozone and aerosol concentration variability is studied over the Euro-Mediterranean area during the months of June and July 2013 and in the framework of the ADRIMED project. A first analysis is performed using meteorological variables, ozone and aerosol concentrations using routine network station, satellite and specific ADRIMED project airborne measurements. This analysis is complemented by modeling using the WRF and CHIMERE regional models.
C. Denjean, P. Formenti, B. Picquet-Varrault, E. Pangui, P. Zapf, Y. Katrib, C. Giorio, A. Tapparo, A. Monod, B. Temime-Roussel, P. Decorse, C. Mangeney, and J. F. Doussin
Atmos. Chem. Phys., 15, 3339–3358, https://doi.org/10.5194/acp-15-3339-2015, https://doi.org/10.5194/acp-15-3339-2015, 2015
P. Nabat, S. Somot, M. Mallet, M. Michou, F. Sevault, F. Driouech, D. Meloni, A. di Sarra, C. Di Biagio, P. Formenti, M. Sicard, J.-F. Léon, and M.-N. Bouin
Atmos. Chem. Phys., 15, 3303–3326, https://doi.org/10.5194/acp-15-3303-2015, https://doi.org/10.5194/acp-15-3303-2015, 2015
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This paper uses an original approach based on a coupled regional aerosol--atmosphere--ocean model to study the dust radiative effects over the Mediterranean in summer 2012. After an evaluation of the prognostic aerosol scheme, the dust aerosol daily variability is shown to improve the simulated surface radiation and temperature at the daily scale. It has also a significant impact on the summer average, thus highlighting the importance of a relevant representation of aerosols in climate models.
C. Denjean, P. Formenti, B. Picquet-Varrault, M. Camredon, E. Pangui, P. Zapf, Y. Katrib, C. Giorio, A. Tapparo, B. Temime-Roussel, A. Monod, B. Aumont, and J. F. Doussin
Atmos. Chem. Phys., 15, 883–897, https://doi.org/10.5194/acp-15-883-2015, https://doi.org/10.5194/acp-15-883-2015, 2015
C. Di Biagio, H. Boucher, S. Caquineau, S. Chevaillier, J. Cuesta, and P. Formenti
Atmos. Chem. Phys., 14, 11093–11116, https://doi.org/10.5194/acp-14-11093-2014, https://doi.org/10.5194/acp-14-11093-2014, 2014
P. Formenti, S. Caquineau, K. Desboeufs, A. Klaver, S. Chevaillier, E. Journet, and J. L. Rajot
Atmos. Chem. Phys., 14, 10663–10686, https://doi.org/10.5194/acp-14-10663-2014, https://doi.org/10.5194/acp-14-10663-2014, 2014
L. Menut, S. Mailler, G. Siour, B. Bessagnet, S. Turquety, G. Rea, R. Briant, M. Mallet, J. Sciare, and P. Formenti
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acpd-14-23075-2014, https://doi.org/10.5194/acpd-14-23075-2014, 2014
Revised manuscript not accepted
C. Denjean, P. Formenti, B. Picquet-Varrault, Y. Katrib, E. Pangui, P. Zapf, and J. F. Doussin
Atmos. Meas. Tech., 7, 183–197, https://doi.org/10.5194/amt-7-183-2014, https://doi.org/10.5194/amt-7-183-2014, 2014
N. Schaller, J. Cermak, M. Wild, and R. Knutti
Earth Syst. Dynam., 4, 253–266, https://doi.org/10.5194/esd-4-253-2013, https://doi.org/10.5194/esd-4-253-2013, 2013
A. Waked, C. Seigneur, F. Couvidat, Y. Kim, K. Sartelet, C. Afif, A. Borbon, P. Formenti, and S. Sauvage
Atmos. Chem. Phys., 13, 5873–5886, https://doi.org/10.5194/acp-13-5873-2013, https://doi.org/10.5194/acp-13-5873-2013, 2013
Related subject area
Subject: Aerosols | Research Activity: Machine Learning | Altitude Range: Troposphere | Science Focus: Physics (physical properties and processes)
Sources and trends of black carbon aerosol in the megacity of Nanjing, eastern China, after the China Clean Action Plan and Three-Year Action Plan
Influencing Factors of Gas-Particle Distribution of Oxygenated Organic Molecules in Urban Atmosphere and its Deviation from Equilibrium Partitioning
Improving the predictions of black carbon (BC) optical properties at various aging stages using a machine-learning-based approach
Abudurexiati Abulimiti, Yanlin Zhang, Mingyuan Yu, Yihang Hong, Yu-Chi Lin, Chaman Gul, and Fang Cao
Atmos. Chem. Phys., 25, 6161–6178, https://doi.org/10.5194/acp-25-6161-2025, https://doi.org/10.5194/acp-25-6161-2025, 2025
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To improve air quality, the Chinese government has implemented strict clean-air measures. We explored how black carbon (BC) responded to these measures and found that a reduction in liquid fuel use was the main factor driving a decrease in BC levels. Additionally, meteorological factors also played a significant role in the long-term trends of BC. These factors should be considered in future emission reduction policies to further enhance air quality improvements.
Xinyu Wang, Nan Chen, Bo Zhu, and Huan Yu
EGUsphere, https://doi.org/10.5194/egusphere-2025-229, https://doi.org/10.5194/egusphere-2025-229, 2025
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Gas-to-particle partitioning governs the fate of organic molecules and the formation of organic aerosols in the atmosphere. Based on field measurement data, we built machine learning models to predict gas-to-particle partitioning. We also unveiled previously unrecognized interactions that lead to the deviations of partitioning from equilibrium state under real atmospheric conditions. Our study provided valuable insights for future research in atmospheric chemistry.
Baseerat Romshoo, Jaikrishna Patil, Tobias Michels, Thomas Müller, Marius Kloft, and Mira Pöhlker
Atmos. Chem. Phys., 24, 8821–8846, https://doi.org/10.5194/acp-24-8821-2024, https://doi.org/10.5194/acp-24-8821-2024, 2024
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Through the use of our machine-learning-based optical model, realistic BC morphologies can be incorporated into atmospheric science applications that require highly accurate results with minimal computational resources. The results of the study demonstrate that the predictions of single-scattering albedo (ω) and mass absorption cross-section (MAC) were improved over the conventional Mie-based predictions when using the machine learning method.
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Short summary
This study investigates the interaction between smoke aerosols and fog and low clouds (FLCs) in the Namib Desert between June and October. Here, a satellite-based dataset of FLCs, reanalysis data and machine learning are used to systematically analyze FLC persistence under different aerosol loadings. Aerosol plumes are shown to modify local thermodynamics, which increase FLC persistence. But fully disentangling aerosol effects from meteorological ones remains a challenge.
This study investigates the interaction between smoke aerosols and fog and low clouds (FLCs) in...
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