Articles | Volume 26, issue 21
https://doi.org/10.5194/acp-26-16047-2026
© Author(s) 2026. 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-26-16047-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
12 Nov 2026
Research article |
| 12 Nov 2026
| 12 Nov 2026
Frequent occurrence of newly formed aerosol particles over wide geographical areas in the Arctic free troposphere and atmospheric boundary layer
Atmospheric Microphysics Department, Leibniz Institute for Tropospheric Research, Leipzig, Germany
Jonas Schaefer
Atmospheric Microphysics Department, Leibniz Institute for Tropospheric Research, Leipzig, Germany
Jörg Hartmann
Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Bremerhaven, Germany
Benjamin Kirbus
Leipzig Institute for Meteorology, Leipzig University, Leipzig, Germany
Joshua Müller
Leipzig Institute for Meteorology, Leipzig University, Leipzig, Germany
Markus Hartmann
Atmospheric Microphysics Department, Leibniz Institute for Tropospheric Research, Leipzig, Germany
Bruno Wetzel
Atmospheric Microphysics Department, Leibniz Institute for Tropospheric Research, Leipzig, Germany
Laura Köhler
Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Bremerhaven, Germany
Anna-Marie Jörss
Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Bremerhaven, Germany
Kay Weinhold
Atmospheric Microphysics Department, Leibniz Institute for Tropospheric Research, Leipzig, Germany
Andreas Herber
Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Bremerhaven, Germany
Zsófia Jurányi
Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Bremerhaven, Germany
Silvia Henning
Atmospheric Microphysics Department, Leibniz Institute for Tropospheric Research, Leipzig, Germany
Gregory C. Roberts
Scripps Institution of Oceanography, La Jolla, CA, USA
Manfred Wendisch
Leipzig Institute for Meteorology, Leipzig University, Leipzig, Germany
Mira L. Pöhlker
Atmospheric Microphysics Department, Leibniz Institute for Tropospheric Research, Leipzig, Germany
Leipzig Institute for Meteorology, Leipzig University, Leipzig, Germany
Frank Stratmann
Atmospheric Microphysics Department, Leibniz Institute for Tropospheric Research, Leipzig, Germany
Related authors
Zsófia Jurányi, Christof Lüpkes, Frank Stratmann, Jörg Hartmann, Jonas Schaefer, Anna-Marie Jörss, Alexander Schulz, Bruno Wetzel, David Simon, Eduard Gebhard, Maximilian Stöhr, Paula Hofmann, Dirk Kalmbach, Sarah Grawe, Manfred Wendisch, and Andreas Herber
Atmos. Meas. Tech., 18, 3477–3494, https://doi.org/10.5194/amt-18-3477-2025, https://doi.org/10.5194/amt-18-3477-2025, 2025
Short summary
Short summary
Understanding the lowest layers of the atmosphere is crucial for climate research, especially in the Arctic. Our study introduces the T-Bird, an aircraft-towed platform designed to measure turbulence and aerosol properties at extremely low altitudes. Traditional aircraft cannot access this region, making the T-Bird a breakthrough for capturing critical atmospheric data. Its first deployment over the Arctic demonstrated its potential to improve our understanding of polar processes.
Sophie Rosenburg, Benjamin Kirbus, Anna Elizabeth Luebke, Michael Schäfer, André Ehrlich, Marcus Klingebiel, Joshua Jeremias Müller, and Manfred Wendisch
EGUsphere, https://doi.org/10.5194/egusphere-2026-5857, https://doi.org/10.5194/egusphere-2026-5857, 2026
This preprint is open for discussion and under review for Atmospheric Chemistry and Physics (ACP).
Short summary
Short summary
The transport of cold and dry air masses across the sea ice edge over the open ocean is often connected to cloud formation. To quantify the coverage and the radiative effect of these clouds, airborne thermal-infrared imaging with high spatial resolution is used. Along the transport pathway the cloud radiative effect is mainly determined by cloud fraction and not by changing cloud properties. This conclusion is found to be still valid for observations with coarser spatial resolution.
Yannick Emanuel Anders, Karoline Block, Mira Pöhlker, and Johannes Quaas
Geosci. Model Dev., 19, 10571–10593, https://doi.org/10.5194/gmd-19-10571-2026, https://doi.org/10.5194/gmd-19-10571-2026, 2026
Short summary
Short summary
Particles in the atmosphere can trigger the formation of cloud droplets, affecting cloud properties and climate. This study evaluates a new global dataset of these particles with measurements from 25 sites around the world. The variability in time and space and their conditional formation behaviour is analysed. The authors identify systematic biases and introduce a simple correction based on observations that greatly improves the dataset's accuracy.
Eva Sommer, Mattia Busato, Pedro Rato, Hannah Klebach, Nirvan Bhattacharyya, Yuanlong Huang, Didier Lombard, Bernhard Mentler, Zhensen Zheng, Theodoros Aivaliotis, João Almeida, Louis-Philippe De Menezes, Ilia Krasin, Robert Kristic, Giulio Malaguti, Pierre Minginette, Sylvain Ravat, Emiliano Urrutia, Stefan Karl Weber, Lubna Dada, Jenna De Vivo, Milin Kaniyodical Sebastian, Paap Koemets, Felix Kunkler, Wiebke Scholz, Prashant Tripathi, Jens Voigtländer, Theodoros Christoudias, Joachim Curtius, Neil Donahue, Imad El Haddad, Roberto Guida, Armin Hansel, Hartwig Harder, Xu-Cheng He, Liine Heikkinen, Heikki Junninen, Markku Kulmala, Katrianne Lehtipalo, Ottmar Möhler, Mira Pöhlker, Rainer Volkamer, Paul Martin Winkler, Richard C. Flagan, Antti Onnela, Serge Mathot, and Jasper Kirkby
EGUsphere, https://doi.org/10.5194/egusphere-2026-6281, https://doi.org/10.5194/egusphere-2026-6281, 2026
This preprint is open for discussion and under review for Atmospheric Measurement Techniques (AMT).
Short summary
Short summary
We present FLOTUS, an oxidation flow tube system developed as an extension to the CERN CLOUD chamber. FLOTUS allows us to simulate atmospheric ageing across a wide range of temperatures, oxidation conditions and gas mixtures. We characterise the flow conditions through simulations and measurements and we demonstrate the production of particles with different sizes and chemical compositions. The gases and particles can be analysed directly or transferred into the CLOUD chamber for further study.
Samuel Ephraim, Paquita Zuidema, Aaron Bansemer, Lintong Cai, Markus Petters, Elise Rosky, Jefferson R. Snider, Zhien Wang, Sarah Woods, Kevin Barry, Theresa Campos, Owen Cruikshank, Sabine Eckhardt, Nikolaos Evangeliou, Romanos Foskinis, Jeffrey R. French, Bart Geerts, Coltin Grasmick, Silvia Henning, Varun Kumar, Andreas Massling, Camille Mavis, Greg M. McFarquhar, Athanasios Nenes, Gunnar Noer, Ryan Patnaude, Russell Perkins, Lise Lotte Sørensen, Henrik Skov, Tyler Tatro, Florian Tornow, and Lu Zhang
Atmos. Chem. Phys., 26, 15375–15404, https://doi.org/10.5194/acp-26-15375-2026, https://doi.org/10.5194/acp-26-15375-2026, 2026
Short summary
Short summary
The processes that establish how mixed-phase closed-cell clouds transition to open-cells are poorly known. First-of-its kind aircraft observations document such a transition in the presence of anomalously high aerosol concentrations, reducing the drop size thereby discouraging riming, over the Nordic Seas at cloud temperatures < −15 °C. Eventually, ice precipitation produces surface cold pools that appear to drive the convective transition, despite strong counteracting surface fluxes.
Ramon C. Braga, Manfred Wendisch, Rachel Albrecht, and Daniel Harrison
Atmos. Chem. Phys., 26, 14769–14791, https://doi.org/10.5194/acp-26-14769-2026, https://doi.org/10.5194/acp-26-14769-2026, 2026
Short summary
Short summary
We introduce a new thermodynamic framework to derive water vapor supersaturation at warm cumulus cloud base from in situ measurements. The framework describes the local transition between saturated thermodynamic states as an adiabatic and reversible process under quasi-isobaric conditions, in which the latent energy released during condensation is partitioned between changes in internal energy and water-vapor expansion work.
Fiona Paulus, Joshua J. Müller, Benjamin Kirbus, Harald Sodemann, Lars van Gelder, Andreas Walbröl, Manfred Wendisch, and Roel A. J. Neggers
Atmos. Chem. Phys., 26, 13983–14014, https://doi.org/10.5194/acp-26-13983-2026, https://doi.org/10.5194/acp-26-13983-2026, 2026
Short summary
Short summary
Cold Arctic air flowing from sea ice onto the warmer ocean waters rapidly warms, moistens, and forms clouds and precipitation. These events shape the Arctic climate but are difficult to observe and model. Particularly the role of large-scale sinking motion during these events is not fully understood. Using rare aircraft data and simulations to track an air mass for two days, we show that strong downward motion suppresses cloud growth, limits and delays precipitation, and reduces cloud lifetimes.
Jonas Schaefer, Sarah Grawe, Hans-Christian Clemen, Stephan Mertes, Johannes Schneider, Bruno Wetzel, Daniel Sauer, Jennifer Wolf, Laura Tomsche, Johanna Mayer, Roland Schrödner, Silvia Henning, Tina Jurkat-Witschas, Christiane Voigt, Helmut Ziereis, Theresa Harlaß, Mira Pöhlker, and Frank Stratmann
Atmos. Chem. Phys., 26, 12505–12520, https://doi.org/10.5194/acp-26-12505-2026, https://doi.org/10.5194/acp-26-12505-2026, 2026
Short summary
Short summary
Ice-nucleating particles (INP) are aerosol particles important for ice formation in clouds droplets and thereby influence climate. This study uses airborne measurements over Europe to show how INP are transported through thunderstorms. We show which particles are washed out and which are are transported into the higher troposphere, where they can again affect cloud ice formation. The findings improve understanding of atmospheric particle distribution and help refine climate models.
Hannah Klebach, Martin Heinritzi, Katharina Kaiser, Lisa Beck, Samuel Ruhl, Samira Atabakhsh, Nirvan Bhattacharyya, Lucía Caudillo-Plath, Philipp Joppe, Thomas Klimach, Peter Lloyd, Mira Pöhlker, Ulrich Pöschl, Sarah Richter, Douglas M. Russell, Johannes Schneider, Marcel Zauner-Wieczorek, and Joachim Curtius
Atmos. Chem. Phys., 26, 12355–12393, https://doi.org/10.5194/acp-26-12355-2026, https://doi.org/10.5194/acp-26-12355-2026, 2026
Short summary
Short summary
Marine atmospheric aerosols remain a major uncertainty in climate models. We report gas and particle phase measurements of two important aerosol forming vapours, sulfuric acid and methanesulfonic acid in the Indo-Pacific. We find that the latter typically dominates over sulfuric acid and contributes significantly to free tropospheric aerosol. Deep convection transports the precursor of both acids to the upper troposphere, providing a key aerosol source in the pristine remote Pacific Ocean.
Lianet Hernández Pardo, Joachim Curtius, Patrick Jöckel, J. Moritz Menken, Christopher Pöhlker, Mira Pöhlker, and Anna Possner
Atmos. Chem. Phys., 26, 12275–12293, https://doi.org/10.5194/acp-26-12275-2026, https://doi.org/10.5194/acp-26-12275-2026, 2026
Short summary
Short summary
Many tiny particles are formed high in the tropical atmosphere, but their impact lower down is unclear. We studied how these particles move downward using long-term computer simulations. We found that particles can reach middle levels of the atmosphere within a week, carried by winds. These results help us understand how pollution and clouds might change as particles spread around the world.
Yifan Yang, Thomas Müller, Baseerat Romshoo, Jens Voigtländer, and Mira L. Pöhlker
EGUsphere, https://doi.org/10.5194/egusphere-2026-5074, https://doi.org/10.5194/egusphere-2026-5074, 2026
Short summary
Short summary
Black carbon particles absorb sunlight and warm the atmosphere. After emission, they become coated by other airborne material, but this coating is not evenly distributed among particles. We found that differences in coating amount and particle size can strongly change the overall light absorption of black carbon. Accounting for this particle-to-particle variability can improve estimates of black carbon’s climate effects.
Esha Semwal, Dietrich Althausen, Ronny Engelmann, Markus Hartmann, Heike Wex, Thomas Oppermann, and Moritz Haarig
EGUsphere, https://doi.org/10.5194/egusphere-2026-4446, https://doi.org/10.5194/egusphere-2026-4446, 2026
Short summary
Short summary
This study presents a new laboratory setup to measure the depolarization ratio of size-resolved aerosol particles in the exact backscattering direction. Measurements with different aerosol types showed that the system can distinguish spherical and non-spherical particles and captures the size dependence of the depolarization ratio. The developed setup is therefore well suited to provide reliable experimental data for improving light-scattering models and the interpretation of lidar observations.
Malte Schuchard, Konrad Bärfuss, Lutz Bretschneider, Thomas Conrath, Andreas Held, Ralf Käthner, Mona Kellermann, Astrid Lampert, Theresa Mathes, Joshua Müller, Christian Pilz, Andreas Schlerf, Holger Siebert, Birgit Wehner, and Barbara Harm-Altstädter
Earth Syst. Sci. Data Discuss., https://doi.org/10.5194/essd-2026-411, https://doi.org/10.5194/essd-2026-411, 2026
Revised manuscript under review for ESSD
Short summary
Short summary
This article combines measurements from an uncrewed aerial system, a tethered balloon system and a surface flux gradient system to study aerosol particles and meteorological parameters at the Arctic site Ny-Ålesund, Svalbard, in spring 2024. The vertical and horizontal observations from the ground to 1.3 kilometres above sea level show strong aerosol variability in correlation with specific meteorological conditions, providing a valuable basis for understanding Arctic aerosol processes.
Patrick C. Taylor, Armin Sorooshian, Rei Ueyama, Sebastian Schmidt, Ihab Abboud, Quincy Allison, Kevin Barry, Sebastian Becker, Holly A. Bender, Joseph R. Bennett, James B. Blair, Niklas Bohn, Linette Boisvert, Matthew D. Brown, Roelof Bruintjes, Anthony Bucholtz, Megan Buzanowicz, Brian Cairns, Filippo Calì Quaglia, Eduard Chemyakin, Bo Chen, Gao Chen, Hong Chen, Yu-Wen Chen, Zezhen Cheng, Swarup China, Dan Chirica, Yonghoon Choi, Peter Colarco, Brian Collister, Ewan Crosbie, Maurice J. Cross, Janet Daniels, Paul DeMott, Joshua P. DiGangi, Alcide Giorgio di Sarra, Glenn S. Diskin, Erica K. Dolinar, Eva-Lou Edwards, Samuel Ephraim, Nikolaos Evangeliou, Romanos Foskinis, Francesca Gallo, Lan Gao, José Luis Gómez-Amo, Daisy Gonzalez, Christine Groot Zwaaftink, Pawan Gupta, Ivan Heckman, Michael Hendrickson, Miguel Ricardo A. Hilario, Ken Hirata, Michelle Hofton, Andrew L. Holen, Ulas Im, Alia L. Khan, Ralph Kahn, Alexei V. Korolev, Sonia Kreidenweis, Thomas Krumpen, Nathan Kurtz, Leslie Lait, Bradley Lamkin, Jack Landy, Nurun Nahar Lata, Paul Lawson, Samuel LeBlanc, Sean Leavor, Jing Li, Thorsten Markus, Hal Maring, Andreas H. Massling, Camille Mavis, Flynn McGinnity, Kerry Meyer, Gabriel Mojica, Richard H. Moore, Parker Morris, Giovanni Muscari, Vikas Nataraja, Amin R. Nehrir, Athanasios Nenes, Edward P. Nowottnick, Matteo Ottaviani, Chelsea Parker, Ryan Patnaude, Michael Perez, Russell J. Perkins, Colten Peterson, Alek Petty, Stevie Phothisane, Chris Polashenski, Kerri A. Pratt, Kayla M. Preisler, John Prytherch, David Rabine, Jens Redemann, Ju-Mee Ryoo, Joseph S. Schlosser, Vanessa Selimovic, Michael A. Shook, Morgan Silverman, Henrik Skov, Alexander Smirnov, Cassidy Soloff, Amy Solomon, Snorre Stamnes, Azusa Takeishi, David R. Thompson, K. Lee Thornhill, Rachel Tilling, Michael Tjernström, Monica Tosco, Pedro C. Valdelomar, David Van Gilst, Jian Wang, Zhien Wang, Andrzej Wasilewski, Manfred Wendisch, Brent Wilder, Edward L. Winstead, Albert Wu, Peng Xian, Lauren M. Zamora, Jiaoshi Zhang, Lei Zhang, Lu Zhang, Luke Ziemba, and Paquita Zuidema
Earth Syst. Sci. Data Discuss., https://doi.org/10.5194/essd-2026-241, https://doi.org/10.5194/essd-2026-241, 2026
Preprint under review for ESSD
Short summary
Short summary
This article summarizes the data sets collected during the Arctic Radiation Cloud aerosol Sea ice Interaction eXperiment (ARCSIX), NASA's most comprehensive Arctic field campaign to date. The overarching goal was to quantify the contributions of surface, clouds, aerosol particles, and precipitation to summer sea ice melt. This paper describes the ARCSIX implementation including the flight strategy, instruments, complementary data sets, access, and usage details.
Aino Ovaska, Daniel Holmberg, Elio Rauth, Mansour Alghamdi, Paulo Artaxo, Eija Asmi, John Backman, Benjamin Bergmans, Matthew Boyer, Liezl Bredenkamp, Maurizio Busetto, Delano Campos De Oliveira, Juan Andrés Casquero-Vera, Darius Ceburnis, Tak Chan, Tommy Chan, Sebastien Conil, Daniele Contini, Suzanne Crumeyrolle, Valentin Duflot, Kostas Eleftheriadis, Johan Esveld, Ekaterina Ezhova, Markus Fiebig, Shahzad Gani, Olga Garmash, Francisco Gómez-Moreno, Roy M. Harrison, Andras Hoffer, Rakesh Hooda, Antti Hyvärinen, Tareq Hussein, Jorma Joutsensaari, Nikos Kalivitis, Heinz Kaminski, Jutta Kesti, Radovan Krejci, Adam Kristensson, Chongai Kuang, Markku Kulmala, Lauri Laakso, Ari Leskinen, Heikki Lihavainen, Andreas Massling, Maik Merkel, Steffen Noe, Jakub Ondracek, Noemí Perez, Jean-Eudes Petit, Tuukka Petäjä, Michael Pikridas, Christopher Pöhlker, Mira Pöhlker, Jean-Philippe Putaud, Ximeng Qi, Cristina Reche, Sergio Rodríguez, Petr Roztocil, Jean Sciare, Karine Sellegri, Dongjie Shang, Ashish Singh, Mikko Sipilä, Henrik Skov, Mar Sorribas, Tamanna Subba, Junying Sun, Peter Tunved, Ville Vakkari, Pieter G. Van Zyl, Aki Virkkula, Jens Voigtländer, Kay Weinhold, Alfred Wiedensohler, Hee-Jung Yoo, Putian Zhou, Kai Puolamäki, Tuomo Nieminen, Veli-Matti Kerminen, Victoria A. Sinclair, and Pauli Paasonen
Earth Syst. Sci. Data Discuss., https://doi.org/10.5194/essd-2026-415, https://doi.org/10.5194/essd-2026-415, 2026
Preprint under review for ESSD
Short summary
Short summary
All clouds form around aerosol particles, and their abundance influences cloud properties. In turn, clouds affect climate by changing how energy moves through the atmosphere, making them important for climate change. To better understand these interactions, we need accurate information on how many aerosol particles are in the atmosphere. Therefore, we have developed a new 21-year global dataset of particle concentrations relevant for cloud formation.
Gabriella Wallentin, Alexander Böhmländer, Ross Herbert, Heike Wex, Charlotte M. Beall, Pia Bogert, Zoé Brasseur, Jie Chen, Jessie M. Creamean, Paul J. DeMott, Oliver Eckermann, Kunfeng Gao, Xianda Gong, Silvia Henning, Naruki Hiranuma, Christina S. McCluskey, Christos Mitsios, Ottmar Möhler, Athanasios Nenes, Mark D. Tarn, Christian Tatzelt, Ping Tian, Yutaka Tobo, Franziska Vogel, André Welti, Elise Wilbourn, Jennifer Winstone, and Corinna Hoose
EGUsphere, https://doi.org/10.5194/egusphere-2026-4134, https://doi.org/10.5194/egusphere-2026-4134, 2026
This preprint is open for discussion and under review for Atmospheric Measurement Techniques (AMT).
Short summary
Short summary
Ice nucleating particles (INPs) are aerosols essential for cloud ice formation in the temperature range -38 °C and 0 °C. Due to measurement challenges, the availability of observations of INPs remains scarce. This study applies machine learning to predict a global INP distribution using aerosol mass concentration reanalysis and observed INPs. This manuscript demonstrates that even with limited measurements, the occurrence of INPs can be estimated, following the spatial pattern of key aerosols.
Matthias Kohl, Christoph Brühl, Holger Tost, Christos Xenofontos, Theodoros Christoudias, Sergey Gromov, Oliver Appel, Stephan Borrmann, Adam Bourassa, Pedro Campunzano-Jost, Yafang Cheng, Oliver Eppers, Karl D. Froyd, Bruna A. Holanda, Jose L. Jimenez, Patrick Jöckel, Philipp Joppe, Katharina Kaiser, Joseph M. Katich, Klaus Klingmüller, Franziska Köllner, Agnieszka Kupc, Anna Martin, Christopher Pöhlker, Mira L. Pöhlker, Ulrich Pöschl, Landon Rieger, Samuel Ruhl, Gregory P. Schill, Johannes Schneider, Christiane Schulz, Joshua P. Schwarz, Alexandra P. Tsimpidi, Ryan Vella, Christina J. Williamson, Yifan Yang, Daniel Zawada, Jos Lelieveld, and Andrea Pozzer
EGUsphere, https://doi.org/10.5194/egusphere-2026-3649, https://doi.org/10.5194/egusphere-2026-3649, 2026
Short summary
Short summary
Aerosols are crucial for Earth's climate, yet their vertical distribution remains poorly understood. We present first consistent global simulations of aerosol distributions and composition from the Earth's surface to the stratosphere, validated by extensive observations. Key findings include a global minimum in aerosol mass in the free troposphere, a significant contribution of organic aerosol in the lower stratosphere, and limited transport of primary particles to the stratosphere.
Azusa Takeishi, Yang Tian, Kamal Kant Chandrakar, Christina McCluskey, Aaron Funk, Courtney Schumacher, and Gregory Roberts
EGUsphere, https://doi.org/10.5194/egusphere-2026-3116, https://doi.org/10.5194/egusphere-2026-3116, 2026
Short summary
Short summary
Four distinct groups of aerosols were identified over the Houston area during the Tracking Aerosol Convection Interactions Experiment (TRACER) field campaign in 2022, based on the unsupervised clustering analysis on the continuous observation of winds and aerosols. The four types of aerosols present different number concentrations, size distributions, locations of origin, and diurnal cycles, and impact shallow cumulus clouds differently in high-resolution numerical simulations.
Hendrik Fuchs, Niklas Illmann, Amalia Muñoz, Mila Ródenas, Bénédicte Picquet-Varrault, M. Rami Alfarra, Cecilia Arsene, Iustinian G. Bejan, David M. Bell, Merete Bilde, Alexander Böhmländer, Mixtli Campos-Pineda, Mathieu Cazaunau, Patrice Coll, Véronique Daële, Claudia Di Biagio, Michael Flynn, Paola Formenti, Hartmut Herrmann, Kristina Höhler, Thorsten Hohaus, Matthew S. Johnson, Eija Juurola, Niku Kivekäs, Jan Kaiser, Christos Kaltsonoudis, Paolo Laj, Dario Massabò, Federico Mazzei, Gordon McFiggans, Max R. McGillen, Abdelwahid Mellouki, Peter Mettke, Ottmar Möhler, Falk Mothes, Dennis Niedermeier, Anna Novelli, Romeo I. Olariu, Spyros N. Pandis, Iulia Patroescu-Klotz, Rosa Maria Petracca Altieri, Paolo Prati, Claudiu Roman, Albert A. Ruth, Harald Saathoff, Silvio Schmalfuß, Frank Stratmann, Virginia Vernocchi, Aristeidis Voliotis, Jens Voigtländer, Annele Virtanen, Andreas Wahner, Robert Wagner, John Wenger, Sören Zorn, Peter Wiesen, and Jean-Francois Doussin
Atmos. Meas. Tech., 19, 4165–4199, https://doi.org/10.5194/amt-19-4165-2026, https://doi.org/10.5194/amt-19-4165-2026, 2026
Short summary
Short summary
Atmospheric simulation chambers enable experiments to be conducted under controlled conditions, improving our understanding of, and ability to predict, changes in the composition of the atmosphere. This is important for assessing air quality and its effects on human health, climate, the environment, and the economy. This paper describes the chambers of the European ACTRIS research infrastructure and discusses topics and directions that can be addressed in future chamber experiments.
Aymeric Dziduch, Antoine Baudoux, Guillaume Mioche, Antoine Canzi, Benjamin Doiteau, Manuel Moser, Emma Järvinen, Étienne Vignon, Jean-Christophe Raut, Régis Dupuy, Christophe Gourbeyre, Jean-Luc Baray, Marie Monier, Frédéric Szczap, Guillaume Penide, Julien Delanoë, Odran Sourdeval, Alfons Schwarzenboeck, Stephan Mertes, Franz Martin Schnaiter, Christiane Voigt, Mario Mech, Susanne Crewell, Andreas Herber, Christof Lüpkes, André Ehrlich, Manfred Wendisch, and Olivier Jourdan
EGUsphere, https://doi.org/10.5194/egusphere-2026-3265, https://doi.org/10.5194/egusphere-2026-3265, 2026
Short summary
Short summary
This study examines the microphysical properties and ice crystal habits of low-level Arctic mixed-phase clouds around Svalbard. Using airborne in situ observations from four campaigns, we show that cloud microphysical structure and ice crystal habits are influenced by weather conditions and surface type. These results provide quantitative observations to better understand low-level Arctic clouds, their ice formation processes, and their influence on the Arctic atmosphere and climate system.
Silke Groß, Florian Ewald, Bjorn Stevens, Martin Wirth, Georgios Dekoutsidis, André Ehrlich, Dimitra Kouklaki, Konstantin Krüger, Sophie Rosenburg, Lea Volkmer, Jonas von Bismark, Lutz Hirsch, Anna E. Luebke, Eleni Marinou, Bernhard Mayer, Montserrat Pinol Sole, Manfred Wendisch, Julia Windmiller, Vassilis Amiridis, Rob Koopman, Takuji Kubota, and Markus Rapp
Atmos. Meas. Tech., 19, 3933–3959, https://doi.org/10.5194/amt-19-3933-2026, https://doi.org/10.5194/amt-19-3933-2026, 2026
Short summary
Short summary
In May 2024 the joint European Space Agency (ESA) and the Japan Aerospace Exploration Agency (JAXA) mission EarthCARE was launched. A similar payload as on the satellite was set up on the German research aircraft HALO, and deployed during an extensive measurement campaign to validated the satellite. We present our instrumentation, the measurements, and its potential for the validation of EarthCARE. We show first validation results and assessments of the EarthCARE data quality.
Babu Suja Arun, Thomas Müller, Mira L. Pöhlker, Andreas Held, Christopher Pöhlker, Manuela van Pinxteren, Yifan Yang, Sabine Lüchtrath, Andreas Walbröl, Janna E. Rückert, Philipp Oehlke, Maik Merkel, and Birgit Wehner
Atmos. Chem. Phys., 26, 7287–7310, https://doi.org/10.5194/acp-26-7287-2026, https://doi.org/10.5194/acp-26-7287-2026, 2026
Short summary
Short summary
Black carbon (BC) aerosols absorb solar radiation and perturb the Arctic energy budget, yet in-situ studies of their microphysical properties and mixing state in the Arctic remain scarce. Based on observations from a shipborne expedition in the Arctic Ocean, we found substantial BC concentrations and showed that warm airmass intrusions enhanced BC levels. Aged BC exhibited enhanced light absorption. These findings will help improve the representation of BC in climate models.
Sebastian Zeppenfeld, Jonas Schaefer, Christian Pilz, Kerstin Ebell, Moritz Zeising, Frank Stratmann, Holger Siebert, Birgit Wehner, Matthias Wietz, Astrid Bracher, and Manuela van Pinxteren
Atmos. Chem. Phys., 26, 7235–7260, https://doi.org/10.5194/acp-26-7235-2026, https://doi.org/10.5194/acp-26-7235-2026, 2026
Short summary
Short summary
Sea spray aerosol transports inorganic salts and carbohydrates from the ocean into the atmosphere. In this field study conducted in Svalbard, we found that carbohydrates reach elevated altitudes that are relevant for cloud formation and properties.
Joanna Alden, Nora Bergner, Benjamin Heutte, Lionel Favre, Mihnea Surdu, Julian Weng, Marta Augugliaro, Patrik Winiger, Berkay Dönmez, Roman Pohorsky, Radiance Calmer, Carmelle Chatterjee, Kalliopi Violaki, Athanasios Nenes, Luke Gregor, Silvia Henning, and Julia Schmale
Atmos. Chem. Phys., 26, 7165–7191, https://doi.org/10.5194/acp-26-7165-2026, https://doi.org/10.5194/acp-26-7165-2026, 2026
Short summary
Short summary
We studied sources, vertical dispersion and properties of aerosols in a Greenlandic fjord system and identified four main types: marine background, local anthropogenic, growth events, biomass burning (BB). Anthropogenic emissions increased absorption coefficients, BB significantly increased the cloud condensation number concentrations, growth events were very similar to background with regards to scattering coefficients. Aerosol properties and origins were distinct throughout the boundary layer.
Sebastian Becker, Konrad Sebastian Schmidt, Hong Chen, Yu-Wen Chen, Kerry G. Meyer, Colten A. Peterson, and Manfred Wendisch
EGUsphere, https://doi.org/10.5194/egusphere-2026-2210, https://doi.org/10.5194/egusphere-2026-2210, 2026
Short summary
Short summary
The melt of Arctic sea ice depends on the radiation budget at the surface, which is largely controlled by the presence of clouds. This cloud radiative effect depends on both cloud properties and surface reflection. Comparing cloud properties from a satellite retrieval and surface reflection data assumed for this retrieval to aircraft measurements, it is found that the assumed surface reflection is too low, leading to a cooling effect of clouds on the surface although a warming effect is present.
Jian Xu, Junteng Wu, Mayur Gajanan Sapkal, Jim Grisillon, Shravan Deshmukh, Brice Temime Roussel, Julien Kammer, Nicolas Brun, Fabien Robert-Peillard, Beiping Luo, Judith Kleinheins, Silvia Henning, Bénédicte Picquet-Varrault, Edouard Pangui, Mathieu Cazaunau, Zamin A. Kanji, Claudia Marcolli, and Anne Monod
Aerosol Research Discuss., https://doi.org/10.5194/ar-2026-14, https://doi.org/10.5194/ar-2026-14, 2026
Revised manuscript under review for AR
Short summary
Short summary
The study aimed to mimic the atmospheric behaviour of a semi-volatile organic compound in the presence of fine particles and at various relative humidities. The objective was to determine the influence of organic matter on humid particle growth. These results are essential for improving our understanding of cloud formation.
Shravan Deshmukh, Laurent Poulain, Birgit Wehner, Silvia Henning, Hartmut Herrmann, and Mira Pöhlker
EGUsphere, https://doi.org/10.5194/egusphere-2026-1992, https://doi.org/10.5194/egusphere-2026-1992, 2026
Short summary
Short summary
Improved representation of aerosol hygroscopicity is critical for understanding how atmospheric particles influence cloud formation, climate, air quality, and human health. This work advances understanding of aerosol hygroscopicity by connecting laboratory measurements of organic aerosol properties with ambient observations through an explainable machine learning framework.
Henning Dorff, Holger Siebert, Komal Navale, André Ehrlich, Joshua Müller, Michael Schäfer, Fan Wu, and Manfred Wendisch
Earth Syst. Sci. Data, 18, 2799–2817, https://doi.org/10.5194/essd-18-2799-2026, https://doi.org/10.5194/essd-18-2799-2026, 2026
Short summary
Short summary
We present tethered-balloon measurements from BELUGA (Balloon-bornE moduLar Utility for profilinG the lower Atmosphere) at Villum Research Station (spring 2024), detailing instrumentation, data processing, and environmental conditions. The data stored in the PANGAEA database include instrument-separated subsets with frequent in situ profiling of thermodynamic, turbulence conditions, and thermal-infrared irradiances across the Arctic atmospheric boundary layer (ABL), supplemented by radiosondes. The data help examine transition events between Arctic ABL states.
Nils Risse, Mario Mech, Catherine Prigent, Joshua J. Müller, and Susanne Crewell
Atmos. Meas. Tech., 19, 2197–2223, https://doi.org/10.5194/amt-19-2197-2026, https://doi.org/10.5194/amt-19-2197-2026, 2026
Short summary
Short summary
Clouds play a crucial role in the Arctic climate system, particularly cloud liquid water droplets. However, there is currently a measurement gap for cloud liquid water over sea ice. We present a method to estimate cloud liquid water over Arctic sea ice using airborne passive microwave observations from the HALO-(𝒜𝒞)3 campaign. Evaluation with other airborne sensors highlights both the limitations and potential of the retrieval. This approach is promising for future applications to satellites.
Wiebke Frey, Silvio Schmalfuß, Frank Stratmann, and Dennis Niedermeier
Earth Syst. Sci. Data, 18, 2305–2318, https://doi.org/10.5194/essd-18-2305-2026, https://doi.org/10.5194/essd-18-2305-2026, 2026
Short summary
Short summary
In order to gain a better understanding on the impact of entrainment on cloud droplet size distributions, water droplets were sprayed into the mixing plane of a turbulent wind tunnel, where two separately conditioned air streams are combined. One air stream resembling 'in cloud' conditions (with relative humidity close to saturation) and one air stream resembling 'out of cloud' conditions, which are dryer and warmer. The paper describes the data set and outlines future use examples.
Holger Gerwig, Wolfram Birmili, Kay Weinhold, Honey Dawn Contecson Alas, Alfred Wiedensohler, and Wilma Travnicek
Aerosol Research, 4, 153–167, https://doi.org/10.5194/ar-4-153-2026, https://doi.org/10.5194/ar-4-153-2026, 2026
Short summary
Short summary
Seven years of hourly particle number size distributions of 10–500 nanometres were measured at an urban background in Germany. A downward trend of total particle number concentrations of −2 % per year was observed. Wind from the Frankfurt Airport showed the highest nucleation mode particle concentrations. Lockdown lowered the concentration of ultrafine particles in the direction of the airport. On 30 % of all days, the World Health Organization's ultrafine particles value for high concentrations was exceeded.
Anna Weber, Benjamin Kirbus, Manfred Wendisch, and Bernhard Mayer
Atmos. Chem. Phys., 26, 3521–3540, https://doi.org/10.5194/acp-26-3521-2026, https://doi.org/10.5194/acp-26-3521-2026, 2026
Short summary
Short summary
Macrophysical and microphysical properties of clouds and their evolution during the initial phase of marine cold air outbreaks in the Arctic are studied with a focus on cloud thermodynamic phase partitioning and phase transitions. To this end, high-resolution quasi-Lagrangian observations of the hyperspectral and polarized imaging system specMACS during the HALO-(AC)3 campaign are combined with backward trajectories. Six cold air outbreaks with varying strengths are analyzed and compared.
Kevin Ohneiser, Markus Hartmann, Heike Wex, Patric Seifert, Anja Hardt, Anna Miller, Katharina Baudrexl, Werner Thomas, Veronika Ettrichrätz, Maximilian Maahn, Tom Gaudek, Willi Schimmel, Fabian Senf, Hannes Griesche, Martin Radenz, and Jan Henneberger
Atmos. Chem. Phys., 26, 3223–3236, https://doi.org/10.5194/acp-26-3223-2026, https://doi.org/10.5194/acp-26-3223-2026, 2026
Short summary
Short summary
This study highlights the efficiency of supercooled liquid-dominated stratus clouds to remove ice-nucleating particles (INPs). When within the planetary boundary layer (PBL), lower concentrations of INPs were measured under supercooled stratus conditions, compared to when the stratus cloud layers occurred at temperatures above freezing. Under supercooling conditions, the free-troposphere above the supercooled stratus covered PBL was found to be an additional potential source of INP.
Manuel Moser, Christiane Voigt, Oliver Eppers, Johannes Lucke, Elena De La Torre Castro, Johanna Mayer, Regis Dupuy, Guillaume Mioche, Olivier Jourdan, Hans-Christian Clemen, Johannes Schneider, Philipp Joppe, Stephan Mertes, Bruno Wetzel, Stephan Borrmann, Marcus Klingebiel, Mario Mech, Christof Lüpkes, Susanne Crewell, André Ehrlich, Andreas Herber, and Manfred Wendisch
Atmos. Chem. Phys., 26, 1867–1887, https://doi.org/10.5194/acp-26-1867-2026, https://doi.org/10.5194/acp-26-1867-2026, 2026
Short summary
Short summary
In this study we analyzed Arctic mixed-phase clouds using airborne in-situ measurements in spring 2022. Based on microphysical properties, we show that within these clouds a distinction must be made between classic mixed-phase clouds and a mixed-phase haze regime. Instead of supercooled droplets, the haze regime contains large wet sea salt aerosols. These findings improve our understanding of Arctic low-level cloud processes.
Sujan Shrestha, Robert E. Holz, Willem J. Marais, Zachary Buckholtz, Ilya Razenkov, Edwin Eloranta, Jeffrey S. Reid, Hope E. Elliott, Nurun Nahar Lata, Zezhen Cheng, Swarup China, Edmund Blades, Albert D. Ortiz, Rebecca Chewitt-Lucas, Alyson Allen, Devon Blades, Ria Agrawal, Elizabeth A. Reid, Jesus Ruiz-Plancarte, Anthony Bucholtz, Ryan Yamaguchi, Qing Wang, Thomas Eck, Elena Lind, Mira L. Pöhlker, Andrew P. Ault, and Cassandra J. Gaston
Atmos. Chem. Phys., 26, 983–999, https://doi.org/10.5194/acp-26-983-2026, https://doi.org/10.5194/acp-26-983-2026, 2026
Short summary
Short summary
Coordinated observations from MAGPIE 2023 show that Saharan dust in the marine atmospheric boundary layer becomes internally mixed with sea spray. This mixing increases particle sphericity and hygroscopicity, likely leading to suppressed lidar linear depolarization ratios despite high dust concentrations. The findings have key implications for interpreting lidar-derived dust retrievals, estimating surface dust from satellite products, and improving dust representation in models.
Kevin Wolf, Evelyn Jäkel, André Ehrlich, Michael Schäfer, Hannes Feilhauer, Andreas Huth, and Manfred Wendisch
Biogeosciences, 22, 7797–7817, https://doi.org/10.5194/bg-22-7797-2025, https://doi.org/10.5194/bg-22-7797-2025, 2025
Short summary
Short summary
This paper presents combined atmosphere-vegetation radiative transfer simulations to systematically investigate cloud-induced biases in remotely sensed vegetation indices (VIs) derived from below-cloud measurements. The biases in VIs have been investigated for the general case of two-band VIs, and for the special cases of the normalized difference vegetation index (NDVI), the normalized difference water index (NDWI), and the enhanced vegetation index (EVI).
Amanda Sellmaier, Ellen Damm, Torsten Sachs, Benjamin Kirbus, Inge Wiekenkamp, Annette Rinke, Falk Pätzold, Daiki Nomura, Astrid Lampert, and Markus Rex
Atmos. Chem. Phys., 25, 17685–17700, https://doi.org/10.5194/acp-25-17685-2025, https://doi.org/10.5194/acp-25-17685-2025, 2025
Short summary
Short summary
This study presents continuous ship-borne measurements of methane (CH4) concentration and isotopic composition monitored during an ice drift expedition in 2020. Using trajectory analysis, we linked atmospheric CH4 variabilities to air mass pathways transported over open water or sea-ice. The study highlights the potential of ship-borne observations to fill significant data gaps in the high Arctic.
Aino Ovaska, Elio Rauth, Daniel Holmberg, Paulo Artaxo, John Backman, Benjamin Bergmans, Don Collins, Marco Aurélio Franco, Shahzad Gani, Roy M. Harrison, Rakesh K. Hooda, Tareq Hussein, Antti-Pekka Hyvärinen, Kerneels Jaars, Adam Kristensson, Markku Kulmala, Lauri Laakso, Ari Laaksonen, Nikolaos Mihalopoulos, Colin O'Dowd, Jakub Ondracek, Tuukka Petäjä, Kristina Plauškaitė, Mira Pöhlker, Ximeng Qi, Peter Tunved, Ville Vakkari, Alfred Wiedensohler, Kai Puolamäki, Tuomo Nieminen, Veli-Matti Kerminen, Victoria A. Sinclair, and Pauli Paasonen
Aerosol Research, 3, 589–618, https://doi.org/10.5194/ar-3-589-2025, https://doi.org/10.5194/ar-3-589-2025, 2025
Short summary
Short summary
We trained machine learning models to estimate the number of aerosol particles large enough to form clouds and generated daily estimates for the entire globe. The models performed well in many continental regions but struggled in remote and marine areas. Still, this approach offers a way to quantify these particles in areas that lack direct measurements, helping us understand their influence on clouds and climate on a global scale.
Valerie Reppert, Olaf Eisen, Holger Schmithüsen, Stefanie Arndt, Guido Ascenso, Linda Ort, and Zsófia Jurányi
EGUsphere, https://doi.org/10.5194/egusphere-2025-5199, https://doi.org/10.5194/egusphere-2025-5199, 2025
Short summary
Short summary
We analyzed 33 years of snow accumulation measurements at Neumayer Station, Antarctica, to understand changes in the amount of snow building up on the surface over time. The long-term, high-resolution data show mostly stable accumulation, but rare positive extremes appeared in 2021 and 2023. Seasonal and multi-year patterns were identified, providing valuable data to improve climate models and satellite observations.
Manfred Wendisch, Benjamin Kirbus, Davide Ori, Matthew D. Shupe, Susanne Crewell, Harald Sodemann, and Vera Schemann
Atmos. Chem. Phys., 25, 15047–15076, https://doi.org/10.5194/acp-25-15047-2025, https://doi.org/10.5194/acp-25-15047-2025, 2025
Short summary
Short summary
Aircraft observations of air parcels moving into and out of the Arctic are reported. From the data, heating and cooling as well as drying and moistening of the air masses along their way into and out of the Arctic could be measured for the first time. These data are used to evaluate if weather prediction models are able to accurately represent these air mass transformations. This work helps to model the future Arctic climate changes, which may have an impact for mid-latitude weather as well.
Kaiqi Wang, Kai Bi, Shuling Chen, Markus Hartmann, Zhijun Wu, Jiyu Gao, Xiaoyu Xu, Yuhan Cheng, Mengyu Huang, Yunbo Chen, Huiwen Xue, Bingbing Wang, Yaqiong Hu, Xiongying Zhang, Xincheng Ma, Ruijie Li, Ping Tian, Ottmar Möhler, Heike Wex, Frank Stratmann, Jie Chen, and Xianda Gong
Atmos. Meas. Tech., 18, 5823–5840, https://doi.org/10.5194/amt-18-5823-2025, https://doi.org/10.5194/amt-18-5823-2025, 2025
Short summary
Short summary
Understanding how ice forms in clouds is crucial for predicting weather and climate; however, accurately measuring the ice-nucleating particles that trigger ice formation remains challenging. We developed an advanced instrument called the Freezing Ice Nucleation Detection Analyzer. By refining temperature control, automating freezing detection, and rigorously testing, we demonstrated that this instrument can reliably measure immersion mode ice-nucleating particles across diverse conditions.
Phuc Thi Minh Ha, Yugo Kanaya, Kazuyo Yamaji, Syuichi Itahashi, Satoru Chatani, Takashi Sekiya, Maria Dolores Andrés Hernández, John Philip Burrows, Hans Schlager, Michael Lichtenstern, Mira Poehlker, and Bruna Holanda
Atmos. Chem. Phys., 25, 13429–13452, https://doi.org/10.5194/acp-25-13429-2025, https://doi.org/10.5194/acp-25-13429-2025, 2025
Short summary
Short summary
Black carbon and CO are important to climate change. EMeRGe airborne observation can identify the suitability of emission inventories used in the CMAQv5.0.2 model for Asian polluted regions. GFEDv4.1s is suitable for fire emissions. Anthropogenic BC and CO emissions from the Philippines (REASv2.1) are insufficient. The estimated Chinese emissions in 2018 are 0.65±0.25 TgBC, 166±65 TgCO, and 12.4±4.8 PgCO2, suggesting a reduction and increment for China's BC and CO emissions in the HTAPv2.2z inventory.
Michail Karalis, Gunilla Svensson, Manfred Wendisch, and Michael Tjernström
Atmos. Chem. Phys., 25, 13177–13198, https://doi.org/10.5194/acp-25-13177-2025, https://doi.org/10.5194/acp-25-13177-2025, 2025
Short summary
Short summary
During the spring warm-air intrusion captured by HALO-(𝒜𝒞)3, the air mass demonstrated a column-like structure. We built a Lagrangian modeling framework using a single-column model (AOSCM) to simulate the air mass transformation. Comparing to observations, reanalysis, and forecast data, we found that the Lagrangian AOSCM can successfully reproduce the main features of the transformation. The Lagrangian AOSCM can be used for future model development to improve Arctic weather and climate prediction.
Sebastian Becker, André Ehrlich, Michael Schäfer, and Manfred Wendisch
Atmos. Chem. Phys., 25, 12831–12842, https://doi.org/10.5194/acp-25-12831-2025, https://doi.org/10.5194/acp-25-12831-2025, 2025
Short summary
Short summary
Clouds interact with solar radiation and can alter the surface temperature. The strength of this cloud impact is driven by cloud properties as well as solar elevation and surface reflection. As these dependencies are poorly represented in climate models, cloud, surface, and radiation observations are used to quantify the contributions of the drivers in the Arctic. It is shown that the weaker surface reflection dominates the stronger cooling effect of clouds over open ocean compared to sea ice.
Joshua J. Müller, Michael Schäfer, Sophie Rosenburg, André Ehrlich, and Manfred Wendisch
Atmos. Meas. Tech., 18, 4695–4708, https://doi.org/10.5194/amt-18-4695-2025, https://doi.org/10.5194/amt-18-4695-2025, 2025
Short summary
Short summary
We retrieved high-resolution maps of Arctic surface temperature and type using an airborne thermal infrared imager during an Arctic aircraft campaign. Our study highlights small-scale surface variability, complementing satellite observations. Surface temperature was retrieved via radiative transfer simulations, while surface type was classified using machine learning. Additionally, we analysed segment sizes of each surface type, presenting results based on their distance from the sea-ice edge.
Marcus Klingebiel, André Ehrlich, Micha Gryschka, Nils Risse, Nina Maherndl, Imke Schirmacher, Sophie Rosenburg, Sabine Hörnig, Manuel Moser, Evelyn Jäkel, Michael Schäfer, Hartwig Deneke, Mario Mech, Christiane Voigt, and Manfred Wendisch
Atmos. Chem. Phys., 25, 9787–9801, https://doi.org/10.5194/acp-25-9787-2025, https://doi.org/10.5194/acp-25-9787-2025, 2025
Short summary
Short summary
Our study is using aircraft measurements from the HALO-(𝒜𝒞)³ campaign to investigate the transition from organized Arctic cloud street structures to more scattered clouds, which we call isotropic cloud patterns. We show that lower wind speeds cause this transition. In addition, we look at the changes in the cloud coverage, the height of the clouds, the cloud particles, and the radiative properties.
Yifan Yang, Thomas Müller, Laurent Poulain, Samira Atabakhsh, Bruna A. Holanda, Jens Voigtländer, Shubhi Arora, and Mira L. Pöhlker
Atmos. Chem. Phys., 25, 8637–8655, https://doi.org/10.5194/acp-25-8637-2025, https://doi.org/10.5194/acp-25-8637-2025, 2025
Short summary
Short summary
Black carbon (BC) is the major atmospheric aerosol that can absorb light and influence climate. We measured the physical properties of BC at a background site in Germany. In summer, BC particles were smaller and the mixture with other atmospheric components occurred during the daytime. In winter, emissions from residential heating significantly influenced BC's properties. Understanding these characteristics of BC can help to improve the accuracy of aerosol optic simulation.
Zsófia Jurányi, Christof Lüpkes, Frank Stratmann, Jörg Hartmann, Jonas Schaefer, Anna-Marie Jörss, Alexander Schulz, Bruno Wetzel, David Simon, Eduard Gebhard, Maximilian Stöhr, Paula Hofmann, Dirk Kalmbach, Sarah Grawe, Manfred Wendisch, and Andreas Herber
Atmos. Meas. Tech., 18, 3477–3494, https://doi.org/10.5194/amt-18-3477-2025, https://doi.org/10.5194/amt-18-3477-2025, 2025
Short summary
Short summary
Understanding the lowest layers of the atmosphere is crucial for climate research, especially in the Arctic. Our study introduces the T-Bird, an aircraft-towed platform designed to measure turbulence and aerosol properties at extremely low altitudes. Traditional aircraft cannot access this region, making the T-Bird a breakthrough for capturing critical atmospheric data. Its first deployment over the Arctic demonstrated its potential to improve our understanding of polar processes.
Kevin Wolf, Evelyn Jäkel, André Ehrlich, Michael Schäfer, Hannes Feilhauer, Andreas Huth, Alexandra Weigelt, and Manfred Wendisch
Biogeosciences, 22, 2909–2933, https://doi.org/10.5194/bg-22-2909-2025, https://doi.org/10.5194/bg-22-2909-2025, 2025
Short summary
Short summary
This paper reports an investigation of the influence of clouds on vegetation albedo using a coupled atmosphere–vegetation radiative transfer model. Both models are iteratively linked to simulate cloud–vegetation–radiation interactions over canopies more realistically. Solar, spectral, and broadband irradiances have been simulated under varying cloud conditions. The simulated irradiances were used to investigate the spectral and broadband effect of clouds on vegetation albedo.
Dennis Niedermeier, Rasmus Hoffmann, Silvio Schmalfuss, Wiebke Frey, Fabian Senf, Olaf Hellmuth, Mira Pöhlker, and Frank Stratmann
Aerosol Research, 3, 219–230, https://doi.org/10.5194/ar-3-219-2025, https://doi.org/10.5194/ar-3-219-2025, 2025
Short summary
Short summary
This study examines the deliquescence behavior of NaCl particles in a turbulent humidity field using the wind tunnel LACIS-T (Turbulent Leipzig Aerosol Cloud Interaction Simulator). The results show that turbulent relative humidity (RH) fluctuations affect the number of deliquesced particles, depending on the mean RH, strength of humidity fluctuations, and particle residence time. It turns out that, in addition to the mean RH, it is essential to consider humidity fluctuations and particle history when determining the phase state of the deliquescent particles.
André Ehrlich, Susanne Crewell, Andreas Herber, Marcus Klingebiel, Christof Lüpkes, Mario Mech, Sebastian Becker, Stephan Borrmann, Heiko Bozem, Matthias Buschmann, Hans-Christian Clemen, Elena De La Torre Castro, Henning Dorff, Regis Dupuy, Oliver Eppers, Florian Ewald, Geet George, Andreas Giez, Sarah Grawe, Christophe Gourbeyre, Jörg Hartmann, Evelyn Jäkel, Philipp Joppe, Olivier Jourdan, Zsófia Jurányi, Benjamin Kirbus, Johannes Lucke, Anna E. Luebke, Maximilian Maahn, Nina Maherndl, Christian Mallaun, Johanna Mayer, Stephan Mertes, Guillaume Mioche, Manuel Moser, Hanno Müller, Veronika Pörtge, Nils Risse, Greg Roberts, Sophie Rosenburg, Johannes Röttenbacher, Michael Schäfer, Jonas Schaefer, Andreas Schäfler, Imke Schirmacher, Johannes Schneider, Sabrina Schnitt, Frank Stratmann, Christian Tatzelt, Christiane Voigt, Andreas Walbröl, Anna Weber, Bruno Wetzel, Martin Wirth, and Manfred Wendisch
Earth Syst. Sci. Data, 17, 1295–1328, https://doi.org/10.5194/essd-17-1295-2025, https://doi.org/10.5194/essd-17-1295-2025, 2025
Short summary
Short summary
This paper provides an overview of the HALO–(AC)3 aircraft campaign data sets, the campaign-specific instrument operation, data processing, and data quality. The data set comprises in situ and remote sensing observations from three research aircraft: HALO, Polar 5, and Polar 6. All data are published in the PANGAEA database by instrument-separated data subsets. It is highlighted how the scientific analysis of the HALO–(AC)3 data benefits from the coordinated operation of three aircraft.
Benjamin Heutte, Nora Bergner, Hélène Angot, Jakob B. Pernov, Lubna Dada, Jessica A. Mirrielees, Ivo Beck, Andrea Baccarini, Matthew Boyer, Jessie M. Creamean, Kaspar R. Daellenbach, Imad El Haddad, Markus M. Frey, Silvia Henning, Tiia Laurila, Vaios Moschos, Tuukka Petäjä, Kerri A. Pratt, Lauriane L. J. Quéléver, Matthew D. Shupe, Paul Zieger, Tuija Jokinen, and Julia Schmale
Atmos. Chem. Phys., 25, 2207–2241, https://doi.org/10.5194/acp-25-2207-2025, https://doi.org/10.5194/acp-25-2207-2025, 2025
Short summary
Short summary
Limited aerosol measurements in the central Arctic hinder our understanding of aerosol–climate interactions in the region. Our year-long observations of aerosol physicochemical properties during the MOSAiC expedition reveal strong seasonal variations in aerosol chemical composition, where the short-term variability is heavily affected by storms in the Arctic. Local wind-generated particles are shown to be an important source of cloud seeds, especially in autumn.
Laura Köhler, Julia Windmiller, Dariusz Baranowski, Michał Brennek, Michał Ciuryło, Lennéa Hayo, Daniel Kȩpski, Stefan Kinne, Beata Latos, Bertrand Lobo, Tobias Marke, Timo Nischik, Daria Paul, Piet Stammes, Artur Szkop, and Olaf Tuinder
Earth Syst. Sci. Data, 17, 633–659, https://doi.org/10.5194/essd-17-633-2025, https://doi.org/10.5194/essd-17-633-2025, 2025
Short summary
Short summary
We present atmospheric and oceanic data from the Atlantic References and Convection ship campaign with the Maria S. Merian from Mindelo to Punta Arenas observed with the integrated ship sensors; humidity and temperature profiler; ceilometer; aerosol instruments (Calitoo, Microtops, and DustTrak); radiosondes; uncrewed aircraft vehicles; and conductivity, temperature, and depth scans. The data include three complete profiles of the Intertropical Convergence Zone and a storm in the South Atlantic.
Inge Wiekenkamp, Anna Katharina Lehmann, Alexander Bütow, Jörg Hartmann, Stefan Metzger, Thomas Ruhtz, Christian Wille, Mathias Zöllner, and Torsten Sachs
Atmos. Meas. Tech., 18, 749–772, https://doi.org/10.5194/amt-18-749-2025, https://doi.org/10.5194/amt-18-749-2025, 2025
Short summary
Short summary
Airborne eddy covariance platforms are crucial to measure three-dimensional wind and turbulent matter and energy transport between the surface and the atmosphere at larger scales. In this study, we introduce a new airborne eddy covariance platform (Schleicher ASK-16) and demonstrate that this platform is able to accurately measure turbulent fluxes and wind vectors. Data from this platform can help to build bridges between local tower measurements and remote-sensing-based products.
Shravan Deshmukh, Laurent Poulain, Birgit Wehner, Silvia Henning, Jean-Eudes Petit, Pauline Fombelle, Olivier Favez, Hartmut Herrmann, and Mira Pöhlker
Atmos. Chem. Phys., 25, 741–758, https://doi.org/10.5194/acp-25-741-2025, https://doi.org/10.5194/acp-25-741-2025, 2025
Short summary
Short summary
Aerosol hygroscopicity has been investigated at a sub-urban site in Paris; analysis shows the sub-saturated regime's measured hygroscopicity and the chemically derived hygroscopic growth, shedding light on the large effect of external particle mixing and its influence on predicting hygroscopicity.
Tabea Rettelbach, Ingmar Nitze, Inge Grünberg, Jennika Hammar, Simon Schäffler, Daniel Hein, Matthias Gessner, Tilman Bucher, Jörg Brauchle, Jörg Hartmann, Torsten Sachs, Julia Boike, and Guido Grosse
Earth Syst. Sci. Data, 16, 5767–5798, https://doi.org/10.5194/essd-16-5767-2024, https://doi.org/10.5194/essd-16-5767-2024, 2024
Short summary
Short summary
Permafrost landscapes in the Arctic are rapidly changing due to climate warming. Here, we publish aerial images and elevation models with very high spatial detail that help study these landscapes in northwestern Canada and Alaska. The images were collected using the Modular Aerial Camera System (MACS). This dataset has significant implications for understanding permafrost landscape dynamics in response to climate change. It is publicly available for further research.
Imke Schirmacher, Sabrina Schnitt, Marcus Klingebiel, Nina Maherndl, Benjamin Kirbus, André Ehrlich, Mario Mech, and Susanne Crewell
Atmos. Chem. Phys., 24, 12823–12842, https://doi.org/10.5194/acp-24-12823-2024, https://doi.org/10.5194/acp-24-12823-2024, 2024
Short summary
Short summary
During Arctic marine cold-air outbreaks, cold air flows from sea ice over open water. Roll circulations evolve, forming cloud streets. We investigate the initial circulation and cloud development using high-resolution airborne measurements. We compute the distance an air mass traveled over water (fetch) from back trajectories. Cloud streets form at 15 km fetch, cloud cover strongly increases at around 20 km, and precipitation forms at around 30 km.
Zoé Brasseur, Julia Schneider, Janne Lampilahti, Ville Vakkari, Victoria A. Sinclair, Christina J. Williamson, Carlton Xavier, Dmitri Moisseev, Markus Hartmann, Pyry Poutanen, Markus Lampimäki, Markku Kulmala, Tuukka Petäjä, Katrianne Lehtipalo, Erik S. Thomson, Kristina Höhler, Ottmar Möhler, and Jonathan Duplissy
Atmos. Chem. Phys., 24, 11305–11332, https://doi.org/10.5194/acp-24-11305-2024, https://doi.org/10.5194/acp-24-11305-2024, 2024
Short summary
Short summary
Ice-nucleating particles (INPs) strongly influence the formation of clouds by initiating the formation of ice crystals. However, very little is known about the vertical distribution of INPs in the atmosphere. Here, we present aircraft measurements of INP concentrations above the Finnish boreal forest. Results show that near-surface INPs are efficiently transported and mixed within the boundary layer and occasionally reach the free troposphere.
Jia Sun, Markus Hermann, Kay Weinhold, Maik Merkel, Wolfram Birmili, Yifan Yang, Thomas Tuch, Harald Flentje, Björn Briel, Ludwig Ries, Cedric Couret, Michael Elsasser, Ralf Sohmer, Klaus Wirtz, Frank Meinhardt, Maik Schütze, Olaf Bath, Bryan Hellack, Veli-Matti Kerminen, Markku Kulmala, Nan Ma, and Alfred Wiedensohler
Atmos. Chem. Phys., 24, 10667–10687, https://doi.org/10.5194/acp-24-10667-2024, https://doi.org/10.5194/acp-24-10667-2024, 2024
Short summary
Short summary
We investigated the characteristics of new particle formation (NPF) for various environments from urban background to high Alpine and the impacts of NPF on cloud condensation nuclei and aerosol radiative forcing. NPF features differ between site categories, implying the crucial role of local environmental factors such as the degree of emissions and meteorological conditions. The results also underscore the importance of local environments when assessing the impact of NPF on climate in models.
Alex Rowell, James Brean, David C. S. Beddows, Zongbo Shi, Avinash Kumar, Matti Rissanen, Miikka Dal Maso, Peter Mettke, Kay Weinhold, Maik Merkel, and Roy M. Harrison
Atmos. Chem. Phys., 24, 10349–10361, https://doi.org/10.5194/acp-24-10349-2024, https://doi.org/10.5194/acp-24-10349-2024, 2024
Short summary
Short summary
Ions enhance the formation and growth rates of new particles, affecting the Earth's radiation budget. Despite these effects, there is little published data exploring the sources of ions in the urban environment and their role in new particle formation (NPF). Here we show that natural ion sources dominate in urban environments, while traffic is a secondary source. Ions contribute up to 12.7 % of the formation rate of particles, indicating that they are important for forming urban PM.
Alex Rowell, James Brean, David C. S. Beddows, Tuukka Petäjä, Máté Vörösmarty, Imre Salma, Jarkko V. Niemi, Hanna E. Manninen, Dominik van Pinxteren, Thomas Tuch, Kay Weinhold, Zongbo Shi, and Roy M. Harrison
Atmos. Chem. Phys., 24, 9515–9531, https://doi.org/10.5194/acp-24-9515-2024, https://doi.org/10.5194/acp-24-9515-2024, 2024
Short summary
Short summary
Different sources of airborne particles in the atmospheres of four European cities were distinguished by recognising their particle size distributions using a statistical procedure, positive matrix factorisation. The various sources responded differently to the changes in emissions associated with COVID-19 lockdowns, and the reasons are investigated. While traffic emissions generally decreased, particles formed from reactions of atmospheric gases decreased in some cities but increased in others.
Luiz A. T. Machado, Jürgen Kesselmeier, Santiago Botía, Hella van Asperen, Meinrat O. Andreae, Alessandro C. de Araújo, Paulo Artaxo, Achim Edtbauer, Rosaria R. Ferreira, Marco A. Franco, Hartwig Harder, Sam P. Jones, Cléo Q. Dias-Júnior, Guido G. Haytzmann, Carlos A. Quesada, Shujiro Komiya, Jost Lavric, Jos Lelieveld, Ingeborg Levin, Anke Nölscher, Eva Pfannerstill, Mira L. Pöhlker, Ulrich Pöschl, Akima Ringsdorf, Luciana Rizzo, Ana M. Yáñez-Serrano, Susan Trumbore, Wanda I. D. Valenti, Jordi Vila-Guerau de Arellano, David Walter, Jonathan Williams, Stefan Wolff, and Christopher Pöhlker
Atmos. Chem. Phys., 24, 8893–8910, https://doi.org/10.5194/acp-24-8893-2024, https://doi.org/10.5194/acp-24-8893-2024, 2024
Short summary
Short summary
Composite analysis of gas concentration before and after rainfall, during the day and night, gives insight into the complex relationship between trace gas variability and precipitation. The analysis helps us to understand the sources and sinks of trace gases within a forest ecosystem. It elucidates processes that are not discernible under undisturbed conditions and contributes to a deeper understanding of the trace gas life cycle and its intricate interactions with cloud dynamics in the Amazon.
Manfred Wendisch, Susanne Crewell, André Ehrlich, Andreas Herber, Benjamin Kirbus, Christof Lüpkes, Mario Mech, Steven J. Abel, Elisa F. Akansu, Felix Ament, Clémantyne Aubry, Sebastian Becker, Stephan Borrmann, Heiko Bozem, Marlen Brückner, Hans-Christian Clemen, Sandro Dahlke, Georgios Dekoutsidis, Julien Delanoë, Elena De La Torre Castro, Henning Dorff, Regis Dupuy, Oliver Eppers, Florian Ewald, Geet George, Irina V. Gorodetskaya, Sarah Grawe, Silke Groß, Jörg Hartmann, Silvia Henning, Lutz Hirsch, Evelyn Jäkel, Philipp Joppe, Olivier Jourdan, Zsofia Jurányi, Michail Karalis, Mona Kellermann, Marcus Klingebiel, Michael Lonardi, Johannes Lucke, Anna E. Luebke, Maximilian Maahn, Nina Maherndl, Marion Maturilli, Bernhard Mayer, Johanna Mayer, Stephan Mertes, Janosch Michaelis, Michel Michalkov, Guillaume Mioche, Manuel Moser, Hanno Müller, Roel Neggers, Davide Ori, Daria Paul, Fiona M. Paulus, Christian Pilz, Felix Pithan, Mira Pöhlker, Veronika Pörtge, Maximilian Ringel, Nils Risse, Gregory C. Roberts, Sophie Rosenburg, Johannes Röttenbacher, Janna Rückert, Michael Schäfer, Jonas Schaefer, Vera Schemann, Imke Schirmacher, Jörg Schmidt, Sebastian Schmidt, Johannes Schneider, Sabrina Schnitt, Anja Schwarz, Holger Siebert, Harald Sodemann, Tim Sperzel, Gunnar Spreen, Bjorn Stevens, Frank Stratmann, Gunilla Svensson, Christian Tatzelt, Thomas Tuch, Timo Vihma, Christiane Voigt, Lea Volkmer, Andreas Walbröl, Anna Weber, Birgit Wehner, Bruno Wetzel, Martin Wirth, and Tobias Zinner
Atmos. Chem. Phys., 24, 8865–8892, https://doi.org/10.5194/acp-24-8865-2024, https://doi.org/10.5194/acp-24-8865-2024, 2024
Short summary
Short summary
The Arctic is warming faster than the rest of the globe. Warm-air intrusions (WAIs) into the Arctic may play an important role in explaining this phenomenon. Cold-air outbreaks (CAOs) out of the Arctic may link the Arctic climate changes to mid-latitude weather. In our article, we describe how to observe air mass transformations during CAOs and WAIs using three research aircraft instrumented with state-of-the-art remote-sensing and in situ measurement devices.
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
Short summary
Short summary
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.
Johannes Röttenbacher, André Ehrlich, Hanno Müller, Florian Ewald, Anna E. Luebke, Benjamin Kirbus, Robin J. Hogan, and Manfred Wendisch
Atmos. Chem. Phys., 24, 8085–8104, https://doi.org/10.5194/acp-24-8085-2024, https://doi.org/10.5194/acp-24-8085-2024, 2024
Short summary
Short summary
Weather prediction models simplify the physical processes related to light scattering by clouds consisting of complex ice crystals. Whether these simplifications are the cause for uncertainties in their prediction can be evaluated by comparing them with measurement data. Here we do this for Arctic ice clouds over sea ice using airborne measurements from two case studies. The model performs well for thick ice clouds but not so well for thin ones. This work can be used to improve the model.
Andreas Walbröl, Janosch Michaelis, Sebastian Becker, Henning Dorff, Kerstin Ebell, Irina Gorodetskaya, Bernd Heinold, Benjamin Kirbus, Melanie Lauer, Nina Maherndl, Marion Maturilli, Johanna Mayer, Hanno Müller, Roel A. J. Neggers, Fiona M. Paulus, Johannes Röttenbacher, Janna E. Rückert, Imke Schirmacher, Nils Slättberg, André Ehrlich, Manfred Wendisch, and Susanne Crewell
Atmos. Chem. Phys., 24, 8007–8029, https://doi.org/10.5194/acp-24-8007-2024, https://doi.org/10.5194/acp-24-8007-2024, 2024
Short summary
Short summary
To support the interpretation of the data collected during the HALO-(AC)3 campaign, which took place in the North Atlantic sector of the Arctic from 7 March to 12 April 2022, we analyze how unusual the weather and sea ice conditions were with respect to the long-term climatology. From observations and ERA5 reanalysis, we found record-breaking warm air intrusions and a large variety of marine cold air outbreaks. Sea ice concentration was mostly within the climatological interquartile range.
Johanna S. Seidel, Alexei A. Kiselev, Alice Keinert, Frank Stratmann, Thomas Leisner, and Susan Hartmann
Atmos. Chem. Phys., 24, 5247–5263, https://doi.org/10.5194/acp-24-5247-2024, https://doi.org/10.5194/acp-24-5247-2024, 2024
Short summary
Short summary
Clouds often contain several thousand times more ice crystals than aerosol particles catalyzing ice formation. This phenomenon, commonly known as ice multiplication, is often explained by secondary ice formation due to the collisions between falling ice particles and droplets. In this study, we mimic this riming process. Contrary to earlier experiments, we found no efficient ice multiplication, which fundamentally questions the importance of the rime-splintering mechanism.
Hanno Müller, André Ehrlich, Evelyn Jäkel, Johannes Röttenbacher, Benjamin Kirbus, Michael Schäfer, Robin J. Hogan, and Manfred Wendisch
Atmos. Chem. Phys., 24, 4157–4175, https://doi.org/10.5194/acp-24-4157-2024, https://doi.org/10.5194/acp-24-4157-2024, 2024
Short summary
Short summary
A weather model is used to compare solar radiation with measurements from an aircraft campaign in the Arctic. Model and observations agree on the downward radiation but show differences in the radiation reflected by the surface and the clouds, which in the model is too low above sea ice and too high above open ocean. The model–observation bias is reduced above open ocean by a realistic fraction of clouds and less cloud liquid water and above sea ice by less dark sea ice and more cloud droplets.
Benjamin Kirbus, Imke Schirmacher, Marcus Klingebiel, Michael Schäfer, André Ehrlich, Nils Slättberg, Johannes Lucke, Manuel Moser, Hanno Müller, and Manfred Wendisch
Atmos. Chem. Phys., 24, 3883–3904, https://doi.org/10.5194/acp-24-3883-2024, https://doi.org/10.5194/acp-24-3883-2024, 2024
Short summary
Short summary
A research aircraft is used to track the changes in air temperature, moisture, and cloud properties for air that moves from cold Arctic sea ice onto warmer oceanic waters. The measurements are compared to two reanalysis models named ERA5 and CARRA. The biggest differences are found for air temperature over the sea ice and moisture over the ocean. CARRA data are more accurate than ERA5 because they better simulate the sea ice, the transition from sea ice to open ocean, and the forming clouds.
Gabriela R. Unfer, Luiz A. T. Machado, Paulo Artaxo, Marco A. Franco, Leslie A. Kremper, Mira L. Pöhlker, Ulrich Pöschl, and Christopher Pöhlker
Atmos. Chem. Phys., 24, 3869–3882, https://doi.org/10.5194/acp-24-3869-2024, https://doi.org/10.5194/acp-24-3869-2024, 2024
Short summary
Short summary
Amazonian aerosols and their interactions with precipitation were studied by understanding them in a 3D space based on three parameters that characterize the concentration and size distribution of aerosols. The results showed characteristic arrangements regarding seasonal and diurnal cycles, as well as when interacting with precipitation. The use of this 3D space appears to be a promising tool for aerosol population analysis and for model validation and parameterization.
Evelyn Jäkel, Sebastian Becker, Tim R. Sperzel, Hannah Niehaus, Gunnar Spreen, Ran Tao, Marcel Nicolaus, Wolfgang Dorn, Annette Rinke, Jörg Brauchle, and Manfred Wendisch
The Cryosphere, 18, 1185–1205, https://doi.org/10.5194/tc-18-1185-2024, https://doi.org/10.5194/tc-18-1185-2024, 2024
Short summary
Short summary
The results of the surface albedo scheme of a coupled regional climate model were evaluated against airborne and ground-based measurements conducted in the European Arctic in different seasons between 2017 and 2022. We found a seasonally dependent bias between measured and modeled surface albedo for cloudless and cloudy situations. The strongest effects of the albedo model bias on the net irradiance were most apparent in the presence of optically thin clouds.
Larissa Lacher, Michael P. Adams, Kevin Barry, Barbara Bertozzi, Heinz Bingemer, Cristian Boffo, Yannick Bras, Nicole Büttner, Dimitri Castarede, Daniel J. Cziczo, Paul J. DeMott, Romy Fösig, Megan Goodell, Kristina Höhler, Thomas C. J. Hill, Conrad Jentzsch, Luis A. Ladino, Ezra J. T. Levin, Stephan Mertes, Ottmar Möhler, Kathryn A. Moore, Benjamin J. Murray, Jens Nadolny, Tatjana Pfeuffer, David Picard, Carolina Ramírez-Romero, Mickael Ribeiro, Sarah Richter, Jann Schrod, Karine Sellegri, Frank Stratmann, Benjamin E. Swanson, Erik S. Thomson, Heike Wex, Martin J. Wolf, and Evelyn Freney
Atmos. Chem. Phys., 24, 2651–2678, https://doi.org/10.5194/acp-24-2651-2024, https://doi.org/10.5194/acp-24-2651-2024, 2024
Short summary
Short summary
Aerosol particles that trigger ice formation in clouds are important for the climate system but are very rare in the atmosphere, challenging measurement techniques. Here we compare three cloud chambers and seven methods for collecting aerosol particles on filters for offline analysis at a mountaintop station. A general good agreement of the methods was found when sampling aerosol particles behind a whole air inlet, supporting their use for obtaining data that can be implemented in models.
Andrea Cuesta-Mosquera, Kristina Glojek, Griša Močnik, Luka Drinovec, Asta Gregorič, Martin Rigler, Matej Ogrin, Baseerat Romshoo, Kay Weinhold, Maik Merkel, Dominik van Pinxteren, Hartmut Herrmann, Alfred Wiedensohler, Mira Pöhlker, and Thomas Müller
Atmos. Chem. Phys., 24, 2583–2605, https://doi.org/10.5194/acp-24-2583-2024, https://doi.org/10.5194/acp-24-2583-2024, 2024
Short summary
Short summary
This study evaluated the air pollution and climate impacts of residential-wood-burning particle emissions from a rural European site. The authors investigate the optical and physical properties that connect the aerosol emissions with climate by evaluating atmospheric radiative impacts via simple-forcing calculations. The study contributes to reducing the lack of information on the understanding of the optical properties of air pollution from anthropogenic sources.
Michael Lonardi, Elisa F. Akansu, André Ehrlich, Mauro Mazzola, Christian Pilz, Matthew D. Shupe, Holger Siebert, and Manfred Wendisch
Atmos. Chem. Phys., 24, 1961–1978, https://doi.org/10.5194/acp-24-1961-2024, https://doi.org/10.5194/acp-24-1961-2024, 2024
Short summary
Short summary
Profiles of thermal-infrared irradiance were measured at two Arctic sites. The presence or lack of clouds influences the vertical structure of these observations. In particular, the cloud top region is a source of radiative energy that can promote cooling and mixing in the cloud layer. Simulations are used to further characterize how the amount of water in the cloud modifies this forcing. A case study additionally showcases the evolution of the radiation profiles in a dynamic atmosphere.
Arto Heitto, Cheng Wu, Diego Aliaga, Luis Blacutt, Xuemeng Chen, Yvette Gramlich, Liine Heikkinen, Wei Huang, Radovan Krejci, Paolo Laj, Isabel Moreno, Karine Sellegri, Fernando Velarde, Kay Weinhold, Alfred Wiedensohler, Qiaozhi Zha, Federico Bianchi, Marcos Andrade, Kari E. J. Lehtinen, Claudia Mohr, and Taina Yli-Juuti
Atmos. Chem. Phys., 24, 1315–1328, https://doi.org/10.5194/acp-24-1315-2024, https://doi.org/10.5194/acp-24-1315-2024, 2024
Short summary
Short summary
Particle growth at the Chacaltaya station in Bolivia was simulated based on measured vapor concentrations and ambient conditions. Major contributors to the simulated growth were low-volatility organic compounds (LVOCs). Also, sulfuric acid had major role when volcanic activity was occurring in the area. This study provides insight on nanoparticle growth at this high-altitude Southern Hemispheric site and hence contributes to building knowledge of early growth of atmospheric particles.
Basudev Swain, Marco Vountas, Adrien Deroubaix, Luca Lelli, Yanick Ziegler, Soheila Jafariserajehlou, Sachin S. Gunthe, Andreas Herber, Christoph Ritter, Hartmut Bösch, and John P. Burrows
Atmos. Meas. Tech., 17, 359–375, https://doi.org/10.5194/amt-17-359-2024, https://doi.org/10.5194/amt-17-359-2024, 2024
Short summary
Short summary
Aerosols are suspensions of particles dispersed in the air. In this study, we use a novel retrieval of satellite data to investigate an optical property of aerosols, the aerosol optical depth, in the high Arctic to assess their direct and indirect roles in climate change. This study demonstrates that the presented approach shows good quality and very promising potential.
Sebastian Zeppenfeld, Manuela van Pinxteren, Markus Hartmann, Moritz Zeising, Astrid Bracher, and Hartmut Herrmann
Atmos. Chem. Phys., 23, 15561–15587, https://doi.org/10.5194/acp-23-15561-2023, https://doi.org/10.5194/acp-23-15561-2023, 2023
Short summary
Short summary
Marine carbohydrates are produced in the surface of the ocean, enter the atmophere as part of sea spray aerosol particles, and potentially contribute to the formation of fog and clouds. Here, we present the results of a sea–air transfer study of marine carbohydrates conducted in the high Arctic. Besides a chemo-selective transfer, we observed a quick atmospheric aging of carbohydrates, possibly as a result of both biotic and abiotic processes.
Elisa F. Akansu, Sandro Dahlke, Holger Siebert, and Manfred Wendisch
Atmos. Chem. Phys., 23, 15473–15489, https://doi.org/10.5194/acp-23-15473-2023, https://doi.org/10.5194/acp-23-15473-2023, 2023
Short summary
Short summary
The height of the mixing layer is an important measure of the surface-level distribution of energy or other substances. The experimental determination of this height is associated with large uncertainties, particularly under stable conditions that we often find during the polar night or in the presence of clouds. We present a reference method using turbulence measurements on a tethered balloon, which allows us to evaluate approaches based on radiosondes or surface observations.
Marcus Klingebiel, André Ehrlich, Elena Ruiz-Donoso, Nils Risse, Imke Schirmacher, Evelyn Jäkel, Michael Schäfer, Kevin Wolf, Mario Mech, Manuel Moser, Christiane Voigt, and Manfred Wendisch
Atmos. Chem. Phys., 23, 15289–15304, https://doi.org/10.5194/acp-23-15289-2023, https://doi.org/10.5194/acp-23-15289-2023, 2023
Short summary
Short summary
In this study we explain how we use aircraft measurements from two Arctic research campaigns to identify cloud properties (like droplet size) over sea-ice and ice-free ocean. To make sure that our measurements make sense, we compare them with other observations. Our results show, e.g., larger cloud droplets in early summer than in spring. Moreover, the cloud droplets are also larger over ice-free ocean than compared to sea ice. In the future, our data can be used to improve climate models.
Sarah Grawe, Conrad Jentzsch, Jonas Schaefer, Heike Wex, Stephan Mertes, and Frank Stratmann
Atmos. Meas. Tech., 16, 4551–4570, https://doi.org/10.5194/amt-16-4551-2023, https://doi.org/10.5194/amt-16-4551-2023, 2023
Short summary
Short summary
Measurements of ice-nucleating particle (INP) concentrations are valuable for the simulation of cloud properties. In recent years, filter sampling in combination with offline INP measurements has become increasingly popular. However, most sampling is ground-based, and the vertical transport of INPs is not well quantified. The High-volume flow aERosol particle filter sAmpler (HERA) for applications on board aircraft was developed to expand the sparse dataset of INP concentrations at cloud level.
Imke Schirmacher, Pavlos Kollias, Katia Lamer, Mario Mech, Lukas Pfitzenmaier, Manfred Wendisch, and Susanne Crewell
Atmos. Meas. Tech., 16, 4081–4100, https://doi.org/10.5194/amt-16-4081-2023, https://doi.org/10.5194/amt-16-4081-2023, 2023
Short summary
Short summary
CloudSat’s relatively coarse spatial resolution, low sensitivity, and blind zone limit its assessment of Arctic low-level clouds, which affect the surface energy balance. We compare cloud fractions from CloudSat and finely resolved airborne radar observations to determine CloudSat’s limitations. Cloudsat overestimates cloud fractions above its blind zone, especially during cold-air outbreaks over open water, and misses a cloud fraction of 32 % and half of the precipitation inside its blind zone.
Jean-Philippe Putaud, Enrico Pisoni, Alexander Mangold, Christoph Hueglin, Jean Sciare, Michael Pikridas, Chrysanthos Savvides, Jakub Ondracek, Saliou Mbengue, Alfred Wiedensohler, Kay Weinhold, Maik Merkel, Laurent Poulain, Dominik van Pinxteren, Hartmut Herrmann, Andreas Massling, Claus Nordstroem, Andrés Alastuey, Cristina Reche, Noemí Pérez, Sonia Castillo, Mar Sorribas, Jose Antonio Adame, Tuukka Petaja, Katrianne Lehtipalo, Jarkko Niemi, Véronique Riffault, Joel F. de Brito, Augustin Colette, Olivier Favez, Jean-Eudes Petit, Valérie Gros, Maria I. Gini, Stergios Vratolis, Konstantinos Eleftheriadis, Evangelia Diapouli, Hugo Denier van der Gon, Karl Espen Yttri, and Wenche Aas
Atmos. Chem. Phys., 23, 10145–10161, https://doi.org/10.5194/acp-23-10145-2023, https://doi.org/10.5194/acp-23-10145-2023, 2023
Short summary
Short summary
Many European people are still exposed to levels of air pollution that can affect their health. COVID-19 lockdowns in 2020 were used to assess the impact of the reduction in human mobility on air pollution across Europe by comparing measurement data with values that would be expected if no lockdown had occurred. We show that lockdown measures did not lead to consistent decreases in the concentrations of fine particulate matter suspended in the air, and we investigate why.
Olivia Linke, Johannes Quaas, Finja Baumer, Sebastian Becker, Jan Chylik, Sandro Dahlke, André Ehrlich, Dörthe Handorf, Christoph Jacobi, Heike Kalesse-Los, Luca Lelli, Sina Mehrdad, Roel A. J. Neggers, Johannes Riebold, Pablo Saavedra Garfias, Niklas Schnierstein, Matthew D. Shupe, Chris Smith, Gunnar Spreen, Baptiste Verneuil, Kameswara S. Vinjamuri, Marco Vountas, and Manfred Wendisch
Atmos. Chem. Phys., 23, 9963–9992, https://doi.org/10.5194/acp-23-9963-2023, https://doi.org/10.5194/acp-23-9963-2023, 2023
Short summary
Short summary
Lapse rate feedback (LRF) is a major driver of the Arctic amplification (AA) of climate change. It arises because the warming is stronger at the surface than aloft. Several processes can affect the LRF in the Arctic, such as the omnipresent temperature inversion. Here, we compare multimodel climate simulations to Arctic-based observations from a large research consortium to broaden our understanding of these processes, find synergy among them, and constrain the Arctic LRF and AA.
Manfred Wendisch, Johannes Stapf, Sebastian Becker, André Ehrlich, Evelyn Jäkel, Marcus Klingebiel, Christof Lüpkes, Michael Schäfer, and Matthew D. Shupe
Atmos. Chem. Phys., 23, 9647–9667, https://doi.org/10.5194/acp-23-9647-2023, https://doi.org/10.5194/acp-23-9647-2023, 2023
Short summary
Short summary
Atmospheric radiation measurements have been conducted during two field campaigns using research aircraft. The data are analyzed to see if the near-surface air in the Arctic is warmed or cooled if warm–humid air masses from the south enter the Arctic or cold–dry air moves from the north from the Arctic to mid-latitude areas. It is important to study these processes and to check if climate models represent them well. Otherwise it is not possible to reliably forecast the future Arctic climate.
Sophie Rosenburg, Charlotte Lange, Evelyn Jäkel, Michael Schäfer, André Ehrlich, and Manfred Wendisch
Atmos. Meas. Tech., 16, 3915–3930, https://doi.org/10.5194/amt-16-3915-2023, https://doi.org/10.5194/amt-16-3915-2023, 2023
Short summary
Short summary
Snow layer melting and melt pond formation on Arctic sea ice are important seasonal processes affecting the surface reflection and energy budget. Sea ice reflectivity was surveyed by airborne imaging spectrometers in May–June 2017. Adapted retrieval approaches were applied to find snow layer liquid water fraction, snow grain effective radius, and melt pond depth. The retrievals show the potential and limitations of spectral airborne imaging to map melting snow layer and melt pond properties.
Dimitri Castarède, Zoé Brasseur, Yusheng Wu, Zamin A. Kanji, Markus Hartmann, Lauri Ahonen, Merete Bilde, Markku Kulmala, Tuukka Petäjä, Jan B. C. Pettersson, Berko Sierau, Olaf Stetzer, Frank Stratmann, Birgitta Svenningsson, Erik Swietlicki, Quynh Thu Nguyen, Jonathan Duplissy, and Erik S. Thomson
Atmos. Meas. Tech., 16, 3881–3899, https://doi.org/10.5194/amt-16-3881-2023, https://doi.org/10.5194/amt-16-3881-2023, 2023
Short summary
Short summary
Clouds play a key role in Earth’s climate by influencing the surface energy budget. Certain types of atmospheric aerosols, called ice-nucleating particles (INPs), induce the formation of ice in clouds and, thus, often initiate precipitation formation. The Portable Ice Nucleation Chamber 2 (PINCii) is a new instrument developed to study ice formation and to conduct ambient measurements of INPs, allowing us to investigate the sources and properties of the atmospheric aerosols that can act as INPs.
Marco Zanatta, Stephan Mertes, Olivier Jourdan, Regis Dupuy, Emma Järvinen, Martin Schnaiter, Oliver Eppers, Johannes Schneider, Zsófia Jurányi, and Andreas Herber
Atmos. Chem. Phys., 23, 7955–7973, https://doi.org/10.5194/acp-23-7955-2023, https://doi.org/10.5194/acp-23-7955-2023, 2023
Short summary
Short summary
Black carbon (BC) particles influence the Arctic radiative balance. Vertical measurements of black carbon were conducted during the ACLOUD campaign in the European Arctic to study the interaction of BC with clouds. This study shows that clouds influence the vertical variability of BC properties across the inversion layer and that multiple activation and transformation mechanisms of BC may occur in the presence of low-level, persistent, mixed-phase clouds.
Manuel Moser, Christiane Voigt, Tina Jurkat-Witschas, Valerian Hahn, Guillaume Mioche, Olivier Jourdan, Régis Dupuy, Christophe Gourbeyre, Alfons Schwarzenboeck, Johannes Lucke, Yvonne Boose, Mario Mech, Stephan Borrmann, André Ehrlich, Andreas Herber, Christof Lüpkes, and Manfred Wendisch
Atmos. Chem. Phys., 23, 7257–7280, https://doi.org/10.5194/acp-23-7257-2023, https://doi.org/10.5194/acp-23-7257-2023, 2023
Short summary
Short summary
This study provides a comprehensive microphysical and thermodynamic phase analysis of low-level clouds in the northern Fram Strait, above the sea ice and the open ocean, during spring and summer. Using airborne in situ cloud data, we show that the properties of Arctic low-level clouds vary significantly with seasonal meteorological situations and surface conditions. The observations presented in this study can help one to assess the role of clouds in the Arctic climate system.
Sebastian Becker, André Ehrlich, Michael Schäfer, and Manfred Wendisch
Atmos. Chem. Phys., 23, 7015–7031, https://doi.org/10.5194/acp-23-7015-2023, https://doi.org/10.5194/acp-23-7015-2023, 2023
Short summary
Short summary
This study analyses the variability of the warming or cooling effect of clouds on the Arctic surface. Therefore, aircraft radiation measurements were performed over sea ice and open ocean during three seasonally different campaigns. It is found that clouds cool the open-ocean surface most strongly in summer. Over sea ice, clouds warm the surface in spring but have a neutral effect in summer. Due to the variable sea ice extent, clouds warm the surface during spring but cool it during late summer.
Samira Atabakhsh, Laurent Poulain, Gang Chen, Francesco Canonaco, André S. H. Prévôt, Mira Pöhlker, Alfred Wiedensohler, and Hartmut Herrmann
Atmos. Chem. Phys., 23, 6963–6988, https://doi.org/10.5194/acp-23-6963-2023, https://doi.org/10.5194/acp-23-6963-2023, 2023
Short summary
Short summary
The study focuses on the aerosol chemical variations found in the rural-background station of Melpitz based on ACSM and MAAP measurements. Source apportionment on both organic aerosol (OA) and black carbon (eBC) was performed, and source seasonality was also linked to air mass trajectories. Overall, three anthropogenic sources were identified in OA and eBC plus two additional aged OA. Our results demonstrate the influence of transported coal-combustion-related OA even during summer time.
Kevin C. H. Sze, Heike Wex, Markus Hartmann, Henrik Skov, Andreas Massling, Diego Villanueva, and Frank Stratmann
Atmos. Chem. Phys., 23, 4741–4761, https://doi.org/10.5194/acp-23-4741-2023, https://doi.org/10.5194/acp-23-4741-2023, 2023
Short summary
Short summary
Ice-nucleating particles (INPs) play an important role in cloud formation and thus in our climate. But little is known about the abundance and properties of INPs, especially in the Arctic, where the temperature increases almost 4 times as fast as that of the rest of the globe. We observe higher INP concentrations and more biological INPs in summer than in winter, likely from local sources. We also provide three equations for estimating INP concentrations in models at different times of the year.
Dmitry G. Chechin, Christof Lüpkes, Jörg Hartmann, André Ehrlich, and Manfred Wendisch
Atmos. Chem. Phys., 23, 4685–4707, https://doi.org/10.5194/acp-23-4685-2023, https://doi.org/10.5194/acp-23-4685-2023, 2023
Short summary
Short summary
Clouds represent a very important component of the Arctic climate system, as they strongly reduce the amount of heat lost to space from the sea ice surface. Properties of clouds, as well as their persistence, strongly depend on the complex interaction of such small-scale properties as phase transitions, radiative transfer and turbulence. In this study we use airborne observations to learn more about the effect of clouds and radiative cooling on turbulence in comparison with other factors.
André Ehrlich, Martin Zöger, Andreas Giez, Vladyslav Nenakhov, Christian Mallaun, Rolf Maser, Timo Röschenthaler, Anna E. Luebke, Kevin Wolf, Bjorn Stevens, and Manfred Wendisch
Atmos. Meas. Tech., 16, 1563–1581, https://doi.org/10.5194/amt-16-1563-2023, https://doi.org/10.5194/amt-16-1563-2023, 2023
Short summary
Short summary
Measurements of the broadband radiative energy budget from aircraft are needed to study the effect of clouds, aerosol particles, and surface conditions on the Earth's energy budget. However, the moving aircraft introduces challenges to the instrument performance and post-processing of the data. This study introduces a new radiometer package, outlines a greatly simplifying method to correct thermal offsets, and provides exemplary measurements of solar and thermal–infrared irradiance.
Chuan-Yao Lin, Wan-Chin Chen, Yi-Yun Chien, Charles C. K. Chou, Chian-Yi Liu, Helmut Ziereis, Hans Schlager, Eric Förster, Florian Obersteiner, Ovid O. Krüger, Bruna A. Holanda, Mira L. Pöhlker, Katharina Kaiser, Johannes Schneider, Birger Bohn, Klaus Pfeilsticker, Benjamin Weyland, Maria Dolores Andrés Hernández, and John P. Burrows
Atmos. Chem. Phys., 23, 2627–2647, https://doi.org/10.5194/acp-23-2627-2023, https://doi.org/10.5194/acp-23-2627-2023, 2023
Short summary
Short summary
During the EMeRGe campaign in Asia, atmospheric pollutants were measured on board the HALO aircraft. The WRF-Chem model was employed to evaluate the biomass burning (BB) plume transported from Indochina and its impact on the downstream areas. The combination of BB aerosol enhancement with cloud water resulted in a reduction in incoming shortwave radiation at the surface in southern China and the East China Sea, which potentially has significant regional climate implications.
Adelaide Dinoi, Daniel Gulli, Kay Weinhold, Ivano Ammoscato, Claudia R. Calidonna, Alfred Wiedensohler, and Daniele Contini
Atmos. Chem. Phys., 23, 2167–2181, https://doi.org/10.5194/acp-23-2167-2023, https://doi.org/10.5194/acp-23-2167-2023, 2023
Short summary
Short summary
In this study, particle number size distribution analysis was performed with the purpose of characterizing new particle formation (NPF) events occurring in two areas of southern Italy over 5 years of measurements. The identification of NPF events produced different results in terms of frequency and seasonality. Some of the main variables involved in the process, the local atmospheric conditions in which the events occurred, and the role of the air masses were discussed and compared.
Haley M. Royer, Mira L. Pöhlker, Ovid Krüger, Edmund Blades, Peter Sealy, Nurun Nahar Lata, Zezhen Cheng, Swarup China, Andrew P. Ault, Patricia K. Quinn, Paquita Zuidema, Christopher Pöhlker, Ulrich Pöschl, Meinrat Andreae, and Cassandra J. Gaston
Atmos. Chem. Phys., 23, 981–998, https://doi.org/10.5194/acp-23-981-2023, https://doi.org/10.5194/acp-23-981-2023, 2023
Short summary
Short summary
This paper presents atmospheric particle chemical composition and measurements of aerosol water uptake properties collected at Ragged Point, Barbados, during the winter of 2020. The result of this study indicates the importance of small African smoke particles for cloud droplet formation in the tropical North Atlantic and highlights the large spatial and temporal pervasiveness of smoke over the Atlantic Ocean.
Yunfan Liu, Hang Su, Siwen Wang, Chao Wei, Wei Tao, Mira L. Pöhlker, Christopher Pöhlker, Bruna A. Holanda, Ovid O. Krüger, Thorsten Hoffmann, Manfred Wendisch, Paulo Artaxo, Ulrich Pöschl, Meinrat O. Andreae, and Yafang Cheng
Atmos. Chem. Phys., 23, 251–272, https://doi.org/10.5194/acp-23-251-2023, https://doi.org/10.5194/acp-23-251-2023, 2023
Short summary
Short summary
The origins of the abundant cloud condensation nuclei (CCN) in the upper troposphere (UT) of the Amazon remain unclear. With model developments of new secondary organic aerosol schemes and constrained by observation, we show that strong aerosol nucleation and condensation in the UT is triggered by biogenic organics, and organic condensation is key for UT CCN production. This UT CCN-producing mechanism may prevail over broader vegetation canopies and deserves emphasis in aerosol–climate feedback.
Matthew Boyer, Diego Aliaga, Jakob Boyd Pernov, Hélène Angot, Lauriane L. J. Quéléver, Lubna Dada, Benjamin Heutte, Manuel Dall'Osto, David C. S. Beddows, Zoé Brasseur, Ivo Beck, Silvia Bucci, Marina Duetsch, Andreas Stohl, Tiia Laurila, Eija Asmi, Andreas Massling, Daniel Charles Thomas, Jakob Klenø Nøjgaard, Tak Chan, Sangeeta Sharma, Peter Tunved, Radovan Krejci, Hans Christen Hansson, Federico Bianchi, Katrianne Lehtipalo, Alfred Wiedensohler, Kay Weinhold, Markku Kulmala, Tuukka Petäjä, Mikko Sipilä, Julia Schmale, and Tuija Jokinen
Atmos. Chem. Phys., 23, 389–415, https://doi.org/10.5194/acp-23-389-2023, https://doi.org/10.5194/acp-23-389-2023, 2023
Short summary
Short summary
The Arctic is a unique environment that is warming faster than other locations on Earth. We evaluate measurements of aerosol particles, which can influence climate, over the central Arctic Ocean for a full year and compare the data to land-based measurement stations across the Arctic. Our measurements show that the central Arctic has similarities to but also distinct differences from the stations further south. We note that this may change as the Arctic warms and sea ice continues to decline.
Yuan Wang, Silvia Henning, Laurent Poulain, Chunsong Lu, Frank Stratmann, Yuying Wang, Shengjie Niu, Mira L. Pöhlker, Hartmut Herrmann, and Alfred Wiedensohler
Atmos. Chem. Phys., 22, 15943–15962, https://doi.org/10.5194/acp-22-15943-2022, https://doi.org/10.5194/acp-22-15943-2022, 2022
Short summary
Short summary
Aerosol particle activation affects cloud, precipitation, radiation, and thus the global climate. Its long-term measurements are important but still scarce. In this study, more than 4 years of measurements at a central European station were analyzed. The overall characteristics and seasonal changes of aerosol particle activation are summarized. The power-law fit between particle hygroscopicity factor and diameter was recommended for predicting cloud
condensation nuclei number concentration.
Baseerat Romshoo, Mira Pöhlker, Alfred Wiedensohler, Sascha Pfeifer, Jorge Saturno, Andreas Nowak, Krzysztof Ciupek, Paul Quincey, Konstantina Vasilatou, Michaela N. Ess, Maria Gini, Konstantinos Eleftheriadis, Chris Robins, François Gaie-Levrel, and Thomas Müller
Atmos. Meas. Tech., 15, 6965–6989, https://doi.org/10.5194/amt-15-6965-2022, https://doi.org/10.5194/amt-15-6965-2022, 2022
Short summary
Short summary
Black carbon (BC) is often assumed to be spherically shaped, causing uncertainties in its optical properties when modelled. This study investigates different modelling techniques for the optical properties of BC by comparing them to laboratory measurements. We provide experimental support for emphasizing the use of appropriate size representation (polydisperse size method) and morphological representation (aggregate morphology) for optical modelling and parameterization scheme development of BC.
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
Short summary
Short summary
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.
Xianda Gong, Martin Radenz, Heike Wex, Patric Seifert, Farnoush Ataei, Silvia Henning, Holger Baars, Boris Barja, Albert Ansmann, and Frank Stratmann
Atmos. Chem. Phys., 22, 10505–10525, https://doi.org/10.5194/acp-22-10505-2022, https://doi.org/10.5194/acp-22-10505-2022, 2022
Short summary
Short summary
The sources of ice-nucleating particles (INPs) are poorly understood in the Southern Hemisphere (SH). We studied INPs in the boundary layer in the southern Patagonia region. No seasonal cycle of INP concentrations was observed. The majority of INPs are biogenic particles, likely from local continental sources. The INP concentrations are higher when strong precipitation occurs. While previous studies focused on marine INP sources in SH, we point out the importance of continental sources of INPs.
Christian Tatzelt, Silvia Henning, André Welti, Andrea Baccarini, Markus Hartmann, Martin Gysel-Beer, Manuela van Pinxteren, Robin L. Modini, Julia Schmale, and Frank Stratmann
Atmos. Chem. Phys., 22, 9721–9745, https://doi.org/10.5194/acp-22-9721-2022, https://doi.org/10.5194/acp-22-9721-2022, 2022
Short summary
Short summary
We present the abundance and origin of cloud-relevant aerosol particles in the preindustral-like conditions of the Southern Ocean (SO) during austral summer. Cloud condensation nuclei (CCN) and ice-nucleating particles (INP) were measured during a circum-Antarctic scientific cruise with in situ instrumentation and offline filter measurements, respectively. Transport processes were found to play an equally important role as local sources for both the CCN and INP population of the SO.
Alexander D. Harrison, Daniel O'Sullivan, Michael P. Adams, Grace C. E. Porter, Edmund Blades, Cherise Brathwaite, Rebecca Chewitt-Lucas, Cassandra Gaston, Rachel Hawker, Ovid O. Krüger, Leslie Neve, Mira L. Pöhlker, Christopher Pöhlker, Ulrich Pöschl, Alberto Sanchez-Marroquin, Andrea Sealy, Peter Sealy, Mark D. Tarn, Shanice Whitehall, James B. McQuaid, Kenneth S. Carslaw, Joseph M. Prospero, and Benjamin J. Murray
Atmos. Chem. Phys., 22, 9663–9680, https://doi.org/10.5194/acp-22-9663-2022, https://doi.org/10.5194/acp-22-9663-2022, 2022
Short summary
Short summary
The formation of ice in clouds fundamentally alters cloud properties; hence it is important we understand the special aerosol particles that can nucleate ice when immersed in supercooled cloud droplets. In this paper we show that African desert dust that has travelled across the Atlantic to the Caribbean nucleates ice much less well than we might have expected.
Zezhen Cheng, Megan Morgenstern, Bo Zhang, Matthew Fraund, Nurun Nahar Lata, Rhenton Brimberry, Matthew A. Marcus, Lynn Mazzoleni, Paulo Fialho, Silvia Henning, Birgit Wehner, Claudio Mazzoleni, and Swarup China
Atmos. Chem. Phys., 22, 9033–9057, https://doi.org/10.5194/acp-22-9033-2022, https://doi.org/10.5194/acp-22-9033-2022, 2022
Short summary
Short summary
We observed a high abundance of liquid and internally mixed particles in samples collected in the North Atlantic free troposphere during summer. We also found several solid and semisolid particles for different emission sources and transport patterns. Our results suggest that considering the mixing state, emission source, and transport patterns of particles is necessary to estimate their phase state in the free troposphere, which is critical for predicting their effects on climate.
Jakub L. Nowak, Robert Grosz, Wiebke Frey, Dennis Niedermeier, Jędrzej Mijas, Szymon P. Malinowski, Linda Ort, Silvio Schmalfuß, Frank Stratmann, Jens Voigtländer, and Tadeusz Stacewicz
Atmos. Meas. Tech., 15, 4075–4089, https://doi.org/10.5194/amt-15-4075-2022, https://doi.org/10.5194/amt-15-4075-2022, 2022
Short summary
Short summary
A high-resolution infrared hygrometer (FIRH) was adapted to measure humidity and its rapid fluctuations in turbulence inside a moist-air wind tunnel LACIS-T where two air streams of different temperature and humidity are mixed. The measurement was achieved from outside the tunnel through its glass windows and provided an agreement with a reference dew-point hygrometer placed inside. The characterization of humidity complements previous investigations of velocity and temperature fields.
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
Short summary
Short summary
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 %.
Simon Kirschler, Christiane Voigt, Bruce Anderson, Ramon Campos Braga, Gao Chen, Andrea F. Corral, Ewan Crosbie, Hossein Dadashazar, Richard A. Ferrare, Valerian Hahn, Johannes Hendricks, Stefan Kaufmann, Richard Moore, Mira L. Pöhlker, Claire Robinson, Amy J. Scarino, Dominik Schollmayer, Michael A. Shook, K. Lee Thornhill, Edward Winstead, Luke D. Ziemba, and Armin Sorooshian
Atmos. Chem. Phys., 22, 8299–8319, https://doi.org/10.5194/acp-22-8299-2022, https://doi.org/10.5194/acp-22-8299-2022, 2022
Short summary
Short summary
In this study we show that the vertical velocity dominantly impacts the cloud droplet number concentration (NC) of low-level clouds over the western North Atlantic in the winter and summer season, while the cloud condensation nuclei concentration, aerosol size distribution and chemical composition impact NC within a season. The observational data presented in this study can evaluate and improve the representation of aerosol–cloud interactions for a wide range of conditions.
Ajit Ahlawat, Kay Weinhold, Jesus Marval, Paolo Tronville, Ari Leskinen, Mika Komppula, Holger Gerwig, Lars Gerling, Stephan Weber, Rikke Bramming Jørgensen, Thomas Nørregaard Jensen, Marouane Merizak, Ulrich Vogt, Carla Ribalta, Mar Viana, Andre Schmitz, Maria Chiesa, Giacomo Gerosa, Lothar Keck, Markus Pesch, Gerhard Steiner, Thomas Krinke, Torsten Tritscher, Wolfram Birmili, and Alfred Wiedensohler
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2022-155, https://doi.org/10.5194/amt-2022-155, 2022
Revised manuscript not accepted
Short summary
Short summary
Measurements of ultrafine particles must be done with quality-assured instruments. The performance of portable instruments such as NanoScan SMPS, and GRIMM Mini WRAS spectrometer measuring the particle number size distribution in the range from 10 to 200 nm were investigated. The influence of different aerosol types and maintenance activities on these instruments were explored. The results show that these portable instruments are suitable for mobile UFP measurements for source identification.
Sebastian Becker, André Ehrlich, Evelyn Jäkel, Tim Carlsen, Michael Schäfer, and Manfred Wendisch
Atmos. Meas. Tech., 15, 2939–2953, https://doi.org/10.5194/amt-15-2939-2022, https://doi.org/10.5194/amt-15-2939-2022, 2022
Short summary
Short summary
Airborne radiation measurements are used to characterize the solar directional reflection of a mixture of Arctic sea ice and open-ocean surfaces in the transition zone between both surface types. The mixture reveals reflection properties of both surface types. It is shown that the directional reflection of the mixture can be reconstructed from the directional reflection of the individual surfaces, accounting for the special conditions present in the transition zone.
M. Dolores Andrés Hernández, Andreas Hilboll, Helmut Ziereis, Eric Förster, Ovid O. Krüger, Katharina Kaiser, Johannes Schneider, Francesca Barnaba, Mihalis Vrekoussis, Jörg Schmidt, Heidi Huntrieser, Anne-Marlene Blechschmidt, Midhun George, Vladyslav Nenakhov, Theresa Harlass, Bruna A. Holanda, Jennifer Wolf, Lisa Eirenschmalz, Marc Krebsbach, Mira L. Pöhlker, Anna B. Kalisz Hedegaard, Linlu Mei, Klaus Pfeilsticker, Yangzhuoran Liu, Ralf Koppmann, Hans Schlager, Birger Bohn, Ulrich Schumann, Andreas Richter, Benjamin Schreiner, Daniel Sauer, Robert Baumann, Mariano Mertens, Patrick Jöckel, Markus Kilian, Greta Stratmann, Christopher Pöhlker, Monica Campanelli, Marco Pandolfi, Michael Sicard, José L. Gómez-Amo, Manuel Pujadas, Katja Bigge, Flora Kluge, Anja Schwarz, Nikos Daskalakis, David Walter, Andreas Zahn, Ulrich Pöschl, Harald Bönisch, Stephan Borrmann, Ulrich Platt, and John P. Burrows
Atmos. Chem. Phys., 22, 5877–5924, https://doi.org/10.5194/acp-22-5877-2022, https://doi.org/10.5194/acp-22-5877-2022, 2022
Short summary
Short summary
EMeRGe provides a unique set of in situ and remote sensing airborne measurements of trace gases and aerosol particles along selected flight routes in the lower troposphere over Europe. The interpretation uses also complementary collocated ground-based and satellite measurements. The collected data help to improve the current understanding of the complex spatial distribution of trace gases and aerosol particles resulting from mixing, transport, and transformation of pollution plumes over Europe.
Manuela van Pinxteren, Tiera-Brandy Robinson, Sebastian Zeppenfeld, Xianda Gong, Enno Bahlmann, Khanneh Wadinga Fomba, Nadja Triesch, Frank Stratmann, Oliver Wurl, Anja Engel, Heike Wex, and Hartmut Herrmann
Atmos. Chem. Phys., 22, 5725–5742, https://doi.org/10.5194/acp-22-5725-2022, https://doi.org/10.5194/acp-22-5725-2022, 2022
Short summary
Short summary
A class of marine particles (transparent exopolymer particles, TEPs) that is ubiquitously found in the world oceans was measured for the first time in ambient marine aerosol particles and marine cloud waters in the tropical Atlantic Ocean. TEPs are likely to have good properties for influencing clouds. We show that TEPs are transferred from the ocean to the marine atmosphere via sea-spray formation and our results suggest that they can also form directly in aerosol particles and in cloud water.
Kristina Glojek, Griša Močnik, Honey Dawn C. Alas, Andrea Cuesta-Mosquera, Luka Drinovec, Asta Gregorič, Matej Ogrin, Kay Weinhold, Irena Ježek, Thomas Müller, Martin Rigler, Maja Remškar, Dominik van Pinxteren, Hartmut Herrmann, Martina Ristorini, Maik Merkel, Miha Markelj, and Alfred Wiedensohler
Atmos. Chem. Phys., 22, 5577–5601, https://doi.org/10.5194/acp-22-5577-2022, https://doi.org/10.5194/acp-22-5577-2022, 2022
Short summary
Short summary
A pilot study to determine the emissions of wood burning under
real-world laboratoryconditions was conducted. We found that measured black carbon (eBC) and particulate matter (PM) in rural shallow terrain depressions with residential wood burning could be much greater than predicted by models. The exceeding levels are a cause for concern since similar conditions can be expected in numerous hilly and mountainous regions across Europe, where approximately 20 % of the total population lives.
Xianda Gong, Heike Wex, Thomas Müller, Silvia Henning, Jens Voigtländer, Alfred Wiedensohler, and Frank Stratmann
Atmos. Chem. Phys., 22, 5175–5194, https://doi.org/10.5194/acp-22-5175-2022, https://doi.org/10.5194/acp-22-5175-2022, 2022
Short summary
Short summary
We conducted 10 yr measurements to characterize the atmospheric aerosol at Cabo Verde. An unsupervised machine learning algorithm, K-means, was implemented to study the aerosol types. Cloud condensation nuclei number concentrations during dust periods were 2.5 times higher than marine periods. The long-term data sets, together with the aerosol classification, can be used as a basis to improve understanding of annual cycles of aerosol, and aerosol-cloud interactions in the North Atlantic.
Janosch Michaelis, Amelie U. Schmitt, Christof Lüpkes, Jörg Hartmann, Gerit Birnbaum, and Timo Vihma
Earth Syst. Sci. Data, 14, 1621–1637, https://doi.org/10.5194/essd-14-1621-2022, https://doi.org/10.5194/essd-14-1621-2022, 2022
Short summary
Short summary
A major goal of the Springtime Atmospheric Boundary Layer Experiment (STABLE) aircraft campaign was to observe atmospheric conditions during marine cold-air outbreaks (MCAOs) originating from the sea-ice-covered Arctic ocean. Quality-controlled measurements of several meteorological variables collected during 15 vertical aircraft profiles and by 22 dropsondes are presented. The comprehensive data set may be used for validating model results to improve the understanding of future trends in MCAOs.
Michael Schäfer, Kevin Wolf, André Ehrlich, Christoph Hallbauer, Evelyn Jäkel, Friedhelm Jansen, Anna Elizabeth Luebke, Joshua Müller, Jakob Thoböll, Timo Röschenthaler, Bjorn Stevens, and Manfred Wendisch
Atmos. Meas. Tech., 15, 1491–1509, https://doi.org/10.5194/amt-15-1491-2022, https://doi.org/10.5194/amt-15-1491-2022, 2022
Short summary
Short summary
The new airborne thermal infrared imager VELOX is introduced. It measures two-dimensional fields of spectral thermal infrared radiance or brightness temperature within the large atmospheric window. The technical specifications as well as necessary calibration and correction procedures are presented. Example measurements from the first field deployment are analysed with respect to cloud coverage and cloud top altitude.
Marco A. Franco, Florian Ditas, Leslie A. Kremper, Luiz A. T. Machado, Meinrat O. Andreae, Alessandro Araújo, Henrique M. J. Barbosa, Joel F. de Brito, Samara Carbone, Bruna A. Holanda, Fernando G. Morais, Janaína P. Nascimento, Mira L. Pöhlker, Luciana V. Rizzo, Marta Sá, Jorge Saturno, David Walter, Stefan Wolff, Ulrich Pöschl, Paulo Artaxo, and Christopher Pöhlker
Atmos. Chem. Phys., 22, 3469–3492, https://doi.org/10.5194/acp-22-3469-2022, https://doi.org/10.5194/acp-22-3469-2022, 2022
Short summary
Short summary
In Central Amazonia, new particle formation in the planetary boundary layer is rare. Instead, there is the appearance of sub-50 nm aerosols with diameters larger than about 20 nm that eventually grow to cloud condensation nuclei size range. Here, 254 growth events were characterized which have higher predominance in the wet season. About 70 % of them showed direct relation to convective downdrafts, while 30 % occurred partly under clear-sky conditions, evidencing still unknown particle sources.
Anna E. Luebke, André Ehrlich, Michael Schäfer, Kevin Wolf, and Manfred Wendisch
Atmos. Chem. Phys., 22, 2727–2744, https://doi.org/10.5194/acp-22-2727-2022, https://doi.org/10.5194/acp-22-2727-2022, 2022
Short summary
Short summary
A combination of aircraft and satellite observations is used to show how the characteristics of tropical shallow clouds interact with incoming and outgoing energy. A complete depiction of these clouds is challenging to obtain, but such data are useful for understanding how models can correctly represent them. The amount of cloud is found to be the most important factor, while other cloud characteristics become increasingly impactful when more cloud is present.
Rupert Holzinger, Oliver Eppers, Kouji Adachi, Heiko Bozem, Markus Hartmann, Andreas Herber, Makoto Koike, Dylan B. Millet, Nobuhiro Moteki, Sho Ohata, Frank Stratmann, and Atsushi Yoshida
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2022-95, https://doi.org/10.5194/acp-2022-95, 2022
Revised manuscript not accepted
Short summary
Short summary
In spring 2018 the research aircraft Polar 5 conducted flights in the Arctic atmosphere. The flight operation was from Station Nord in Greenland, 1700 km north of the Arctic Circle (81°43'N, 17°47'W). Using a mass spectrometer we measured more than 100 organic compounds in the air. We found a clear signature of natural organic compounds that are transported from forests to the high Arctic. These compounds have the potential to change the cloud cover and energy budget of the Arctic region.
Anna A. Shestakova, Dmitry G. Chechin, Christof Lüpkes, Jörg Hartmann, and Marion Maturilli
Atmos. Chem. Phys., 22, 1529–1548, https://doi.org/10.5194/acp-22-1529-2022, https://doi.org/10.5194/acp-22-1529-2022, 2022
Short summary
Short summary
This article presents a comprehensive analysis of the easterly orographic wind episode which occurred over Svalbard on 30–31 May 2017. This wind caused a significant temperature rise on the lee side of the mountains and greatly intensified the snowmelt. This episode was investigated on the basis of measurements collected during the ACLOUD/PASCAL field campaigns with the help of numerical modeling.
Luiz A. T. Machado, Marco A. Franco, Leslie A. Kremper, Florian Ditas, Meinrat O. Andreae, Paulo Artaxo, Micael A. Cecchini, Bruna A. Holanda, Mira L. Pöhlker, Ivan Saraiva, Stefan Wolff, Ulrich Pöschl, and Christopher Pöhlker
Atmos. Chem. Phys., 21, 18065–18086, https://doi.org/10.5194/acp-21-18065-2021, https://doi.org/10.5194/acp-21-18065-2021, 2021
Short summary
Short summary
Several studies evaluate aerosol–cloud interactions, but only a few attempted to describe how clouds modify aerosol properties. This study evaluates the effect of weather events on the particle size distribution at the ATTO, combining remote sensing and in situ data. Ultrafine, Aitken and accumulation particles modes have different behaviors for the diurnal cycle and for rainfall events. This study opens up new scientific questions that need to be pursued in detail in new field campaigns.
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
Short summary
Short summary
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.
Heike Konow, Florian Ewald, Geet George, Marek Jacob, Marcus Klingebiel, Tobias Kölling, Anna E. Luebke, Theresa Mieslinger, Veronika Pörtge, Jule Radtke, Michael Schäfer, Hauke Schulz, Raphaela Vogel, Martin Wirth, Sandrine Bony, Susanne Crewell, André Ehrlich, Linda Forster, Andreas Giez, Felix Gödde, Silke Groß, Manuel Gutleben, Martin Hagen, Lutz Hirsch, Friedhelm Jansen, Theresa Lang, Bernhard Mayer, Mario Mech, Marc Prange, Sabrina Schnitt, Jessica Vial, Andreas Walbröl, Manfred Wendisch, Kevin Wolf, Tobias Zinner, Martin Zöger, Felix Ament, and Bjorn Stevens
Earth Syst. Sci. Data, 13, 5545–5563, https://doi.org/10.5194/essd-13-5545-2021, https://doi.org/10.5194/essd-13-5545-2021, 2021
Short summary
Short summary
The German research aircraft HALO took part in the research campaign EUREC4A in January and February 2020. The focus area was the tropical Atlantic east of the island of Barbados. We describe the characteristics of the 15 research flights, provide auxiliary information, derive combined cloud mask products from all instruments that observe clouds on board the aircraft, and provide code examples that help new users of the data to get started.
Sebastian Landwehr, Michele Volpi, F. Alexander Haumann, Charlotte M. Robinson, Iris Thurnherr, Valerio Ferracci, Andrea Baccarini, Jenny Thomas, Irina Gorodetskaya, Christian Tatzelt, Silvia Henning, Rob L. Modini, Heather J. Forrer, Yajuan Lin, Nicolas Cassar, Rafel Simó, Christel Hassler, Alireza Moallemi, Sarah E. Fawcett, Neil Harris, Ruth Airs, Marzieh H. Derkani, Alberto Alberello, Alessandro Toffoli, Gang Chen, Pablo Rodríguez-Ros, Marina Zamanillo, Pau Cortés-Greus, Lei Xue, Conor G. Bolas, Katherine C. Leonard, Fernando Perez-Cruz, David Walton, and Julia Schmale
Earth Syst. Dynam., 12, 1295–1369, https://doi.org/10.5194/esd-12-1295-2021, https://doi.org/10.5194/esd-12-1295-2021, 2021
Short summary
Short summary
The Antarctic Circumnavigation Expedition surveyed a large number of variables describing the dynamic state of ocean and atmosphere, freshwater cycle, atmospheric chemistry, ocean biogeochemistry, and microbiology in the Southern Ocean. To reduce the dimensionality of the dataset, we apply a sparse principal component analysis and identify temporal patterns from diurnal to seasonal cycles, as well as geographical gradients and
hotspotsof interaction. Code and data are open access.
Clémence Rose, Martine Collaud Coen, Elisabeth Andrews, Yong Lin, Isaline Bossert, Cathrine Lund Myhre, Thomas Tuch, Alfred Wiedensohler, Markus Fiebig, Pasi Aalto, Andrés Alastuey, Elisabeth Alonso-Blanco, Marcos Andrade, Begoña Artíñano, Todor Arsov, Urs Baltensperger, Susanne Bastian, Olaf Bath, Johan Paul Beukes, Benjamin T. Brem, Nicolas Bukowiecki, Juan Andrés Casquero-Vera, Sébastien Conil, Konstantinos Eleftheriadis, Olivier Favez, Harald Flentje, Maria I. Gini, Francisco Javier Gómez-Moreno, Martin Gysel-Beer, Anna Gannet Hallar, Ivo Kalapov, Nikos Kalivitis, Anne Kasper-Giebl, Melita Keywood, Jeong Eun Kim, Sang-Woo Kim, Adam Kristensson, Markku Kulmala, Heikki Lihavainen, Neng-Huei Lin, Hassan Lyamani, Angela Marinoni, Sebastiao Martins Dos Santos, Olga L. Mayol-Bracero, Frank Meinhardt, Maik Merkel, Jean-Marc Metzger, Nikolaos Mihalopoulos, Jakub Ondracek, Marco Pandolfi, Noemi Pérez, Tuukka Petäjä, Jean-Eudes Petit, David Picard, Jean-Marc Pichon, Veronique Pont, Jean-Philippe Putaud, Fabienne Reisen, Karine Sellegri, Sangeeta Sharma, Gerhard Schauer, Patrick Sheridan, James Patrick Sherman, Andreas Schwerin, Ralf Sohmer, Mar Sorribas, Junying Sun, Pierre Tulet, Ville Vakkari, Pieter Gideon van Zyl, Fernando Velarde, Paolo Villani, Stergios Vratolis, Zdenek Wagner, Sheng-Hsiang Wang, Kay Weinhold, Rolf Weller, Margarita Yela, Vladimir Zdimal, and Paolo Laj
Atmos. Chem. Phys., 21, 17185–17223, https://doi.org/10.5194/acp-21-17185-2021, https://doi.org/10.5194/acp-21-17185-2021, 2021
Short summary
Short summary
Aerosol particles are a complex component of the atmospheric system the effects of which are among the most uncertain in climate change projections. Using data collected at 62 stations, this study provides the most up-to-date picture of the spatial distribution of particle number concentration and size distribution worldwide, with the aim of contributing to better representation of aerosols and their interactions with clouds in models and, therefore, better evaluation of their impact on climate.
Cited articles
Allan, J. D., Williams, P. I., Najera, J., Whitehead, J. D., Flynn, M. J., Taylor, J. W., Liu, D., Darbyshire, E., Carpenter, L. J., Chance, R., Andrews, S. J., Hackenberg, S. C., and McFiggans, G.: Iodine observed in new particle formation events in the Arctic atmosphere during ACCACIA, Atmos. Chem. Phys., 15, 5599–5609, https://doi.org/10.5194/acp-15-5599-2015, 2015. a, b, c
Andreae, M. and Rosenfeld, D.: Aerosol–cloud–precipitation interactions. Part 1. The nature and sources of cloud-active aerosols, Earth-Sci. Rev., 89, 13–41, https://doi.org/10.1016/j.earscirev.2008.03.001, 2008. a
Asmi, E., Kondratyev, V., Brus, D., Laurila, T., Lihavainen, H., Backman, J., Vakkari, V., Aurela, M., Hatakka, J., Viisanen, Y., Uttal, T., Ivakhov, V., and Makshtas, A.: Aerosol size distribution seasonal characteristics measured in Tiksi, Russian Arctic, Atmos. Chem. Phys., 16, 1271–1287, https://doi.org/10.5194/acp-16-1271-2016, 2016. a
Atkinson, H. M., Huang, R.-J., Chance, R., Roscoe, H. K., Hughes, C., Davison, B., Schönhardt, A., Mahajan, A. S., Saiz-Lopez, A., Hoffmann, T., and Liss, P. S.: Iodine emissions from the sea ice of the Weddell Sea, Atmos. Chem. Phys., 12, 11229–11244, https://doi.org/10.5194/acp-12-11229-2012, 2012. a
Baccarini, A., Karlsson, L., Dommen, J., Duplessis, P., Vüllers, J., Brooks, I. M., Saiz-Lopez, A., Salter, M., Tjernström, M., Baltensperger, U., Zieger, P., and Schmale, J.: Frequent new particle formation over the high Arctic pack ice by enhanced iodine emissions, Nat. Commun., 11, 4924, https://doi.org/10.1038/s41467-020-18551-0, 2020. a, b, c
Beck, L. J., Sarnela, N., Junninen, H., Hoppe, C. J. M., Garmash, O., Bianchi, F., Riva, M., Rose, C., Peräkylä, O., Wimmer, D., Kausiala, O., Jokinen, T., Ahonen, L., Mikkilä, J., Hakala, J., He, X.-C., Kontkanen, J., Wolf, K. K. E., Cappelletti, D., Mazzola, M., Traversi, R., Petroselli, C., Viola, A. P., Vitale, V., Lange, R., Massling, A., Nøjgaard, J. K., Krejci, R., Karlsson, L., Zieger, P., Jang, S., Lee, K., Vakkari, V., Lampilahti, J., Thakur, R. C., Leino, K., Kangasluoma, J., Duplissy, E.-M., Siivola, E., Marbouti, M., Tham, Y. J., Saiz-Lopez, A., Petäjä, T., Ehn, M., Worsnop, D. R., Skov, H., Kulmala, M., Kerminen, V.-M., and Sipilä, M.: Differing mechanisms of new particle formation at two Arctic sites, Geophys. Res. Lett., 48, e2020GL091334, https://doi.org/10.1029/2020GL091334, 2021. a, b, c
Bigg, E. K. and Leck, C.: Cloud-active particles over the central Arctic Ocean, J. Geophys. Res.-Atmos., 106, 32155–32166, https://doi.org/10.1029/1999JD901152, 2001. a
Bintanja, R., van der Wiel, K., van der Linden, E. C., Reusen, J., Bogerd, L., Krikken, F., and Selten, F. M.: Strong future increases in Arctic precipitation variability linked to poleward moisture transport, Sci. Adv., 6, eaax6869, https://doi.org/10.1126/sciadv.aax6869, 2020. a
Box, J. E., Colgan, W. T., Christensen, T. R., Schmidt, N. M., Lund, M., Parmentier, F.-J. W., Brown, R., Bhatt, U. S., Euskirchen, E. S., Romanovsky, V. E., Walsh, J. E., Overland, J. E., Wang, M., Corell, R. W., Meier, W. N., Wouters, B., Mernild, S., Mård, J., Pawlak, J., and Olsen, M. S.: Key indicators of Arctic climate change: 1971–2017, Environ. Res. Lett., 14, 045010, https://doi.org/10.1088/1748-9326/aafc1b, 2019. a
Burkart, J., Willis, M. D., Bozem, H., Thomas, J. L., Law, K., Hoor, P., Aliabadi, A. A., Köllner, F., Schneider, J., Herber, A., Abbatt, J. P. D., and Leaitch, W. R.: Summertime observations of elevated levels of ultrafine particles in the high Arctic marine boundary layer, Atmos. Chem. Phys., 17, 5515–5535, https://doi.org/10.5194/acp-17-5515-2017, 2017. a, b, c, d
Carslaw, K., Lee, L., Reddington, C., Pringle, K., Rap, A., Forster, P., Mann, G., Spracklen, D., Woodhouse, M., Regayre, L., and Pierce, J.: Large contribution of natural aerosols to uncertainty in indirect forcing, Nature, 503, 67–71, https://doi.org/10.1038/nature12674, 2013. a
Clarke, A., Varner, J., Eisele, F., Mauldin, R., Tanner, D., and Litchy, M.: Particle production in the remote marine atmosphere: Cloud outflow and subsidence during ACE 1, J. Geophys. Res.-Atmos., 103, 16397–16409, https://doi.org/10.1029/97JD02987, 1998. a
Croft, B., Wentworth, G. R., Martin, R. V., Leaitch, W. R., Murphy, J. G., Murphy, B. N., Kodros, J. K., Abbatt, J. P., and Pierce, J. R.: Contribution of Arctic seabird-colony ammonia to atmospheric particles and cloud-albedo radiative effect, Nat. Commun., 7, 13444, https://doi.org/10.1038/ncomms13444, 2016. a
Cuevas, C. A., Maffezzoli, N., Corella, J. P., Spolaor, A., Vallelonga, P., Kjær, H. A., Simonsen, M., Winstrup, M., Vinther, B., Horvat, C., Fernandez, R. P., Kinnison, D., Lamarque, J.-F., Barbante, C., and Saiz-Lopez, A.: Rapid increase in atmospheric iodine levels in the North Atlantic since the mid-20th century, Nat. Commun., 9, 1452, https://doi.org/10.1038/s41467-018-03756-1, 2018. a, b
Dada, L., Angot, H., Beck, I., Baccarini, A., Quéléver, L. L., Boyer, M., Laurila, T., Brasseur, Z., Jozef, G., De Boer, G., Shupe, M. D., Henning, S., Bucci, S., Dütsch, M., Stohl, A., Petäjä, T., Daellenbach, K. R., Jokinen, T., and Schmale, J.: A central arctic extreme aerosol event triggered by a warm air-mass intrusion, Nat. Commun., 13, 5290, https://doi.org/10.1038/s41467-022-32872-2, 2022. a
Dall’Osto, M., Beddows, D., Tunved, P., Krejci, R., Ström, J., Hansson, H.-C., Yoon, Y., Park, K.-T., Becagli, S., Udisti, R., Onasch, T., O´Dowd, C. D., Simó, R., and Harrison, R. M.: Arctic sea ice melt leads to atmospheric new particle formation, Sci. Rep., 7, 3318, https://doi.org/10.1038/s41598-017-03328-1, 2017. a
Dall'Osto, M., Geels, C., Beddows, D., Boertmann, D., Lange, R., Nøjgaard, J., Harrison, R. M., Simo, R., Skov, H., and Massling, A.: Regions of open water and melting sea ice drive new particle formation in North East Greenland, Sci. Rep., 8, 6109, https://doi.org/10.1038/s41598-018-24426-8, 2018. a
Engvall, A.-C., Krejci, R., Ström, J., Minikin, A., Treffeisen, R., Stohl, A., and Herber, A.: In-situ airborne observations of the microphysical properties of the Arctic tropospheric aerosol during late spring and summer, Tellus B, 60, 392–404, https://doi.org/10.1111/j.1600-0889.2008.00348.x, 2008. a
E.U. Copernicus Marine Service Information (CMEMS): Global Ocean Colour (Copernicus-GlobColour), Bio-Geo-Chemical, L4 (monthly and interpolated) from Satellite Observations (1997–ongoing), Marine Data Store (MDS) [data set], https://doi.org/10.48670/moi-00281, 2025. a
Forster, P., Storelvmo, T., Armour, K., Collins, W., Dufresne, J.-L., Frame, D., Lunt, D. J., Mauritsen, T., Palmer, M. D., Watanabe, M., Wild, M., and Zhang, H.: The Earth's Energy Budget, Climate Feedbacks, and Climate Sensitivity, in: Climate Change 2021: The Physical Science Basis. Contribution of Working Group I to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change, edited by: Masson-Delmotte, V., Zhai, P., Pirani, A., Connors, S. L., Péan, C., Berger, S., Caud, N., Chen, Y., Goldfarb, L., Gomis, M. I., Huang, M., Leitzell, K., Lonnoy, E., Matthews, J. B. R., Maycock, T. K., Waterfield, T., Yelekçi, O., Yu, R., and Zhou, B., Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA, 923–1054, https://doi.org/10.1017/9781009157896.009, 2021. a, b
Freud, E., Krejci, R., Tunved, P., Leaitch, R., Nguyen, Q. T., Massling, A., Skov, H., and Barrie, L.: Pan-Arctic aerosol number size distributions: seasonality and transport patterns, Atmos. Chem. Phys., 17, 8101–8128, https://doi.org/10.5194/acp-17-8101-2017, 2017. a
Galí, M., Devred, E., Babin, M., and Levasseur, M.: Decadal increase in Arctic dimethylsulfide emission, P. Natl. Acad. Sci. USA, 116, 19311–19317, https://doi.org/10.1073/pnas.190437811, 2019. a
Gálvez, Ó., Baeza-Romero, M. T., Sanz, M., and Saiz-Lopez, A.: Photolysis of frozen iodate salts as a source of active iodine in the polar environment, Atmos. Chem. Phys., 16, 12703–12713, https://doi.org/10.5194/acp-16-12703-2016, 2016. a
Garrett, T. J., Hobbs, P. V., and Radke, L. F.: High Aitken nucleus concentrations above cloud tops in the Arctic, J. Atmos. Sci., 59, 779–783, https://doi.org/10.1175/1520-0469(2001)059<0779:HANCAC>2.0.CO;2, 2002. a, b
Gordon, H., Kirkby, J., Baltensperger, U., Bianchi, F., Breitenlechner, M., Curtius, J., Dias, A., Dommen, J., Donahue, N. M., Dunne, E. M., Duplissy, J., Ehrhart, S., Flagan, R. C., Frege, C., Fuchs, C., Hansel, A., Hoyle, C. R., Kulmala, M., Kürten, A., Lehtipalo, K., Makhmutov, V., Molteni, U., Rissanen, M. P., Stozkhov, Y., Tröstl, J., Tsagkogeorgas, G., Wagner, R., Williamson, C., Wimmer, D., Winkler, P. M., Yan, C., and Carslaw, K. S.: Causes and importance of new particle formation in the present-day and preindustrial atmospheres, J. Geophys. Res.-Atmos., 122, 8739–8760, https://doi.org/10.1002/2017JD026844, 2017. a, b
Hartmann, J., Gehrmann, M., Kohnert, K., Metzger, S., and Sachs, T.: New calibration procedures for airborne turbulence measurements and accuracy of the methane fluxes during the AirMeth campaigns, Atmos. Meas. Tech., 11, 4567–4581, https://doi.org/10.5194/amt-11-4567-2018, 2018. a
Hegg, D. A., Radke, L. F., and Hobbs, P. V.: Particle production associated with marine clouds, J. Geophys. Res.-Atmos., 95, 13917–13926, https://doi.org/10.1029/JD095iD09p13917, 1990. a
Hersbach, H., Bell, B., Berrisford, P., Hirahara, S., Horányi, A., Muñoz-Sabater, J., Nicolas, J., Peubey, C., Radu, R., Schepers, D., Simmons, A., Soci, C., Abdalla, S., Abellan, X., Balsamo, G., Bechtold, P., Biavati, G., Bidlot, J., Bonavita, M., De Chiara, G., Dahlgren,P., Dee, D., Diamantakis, M., Dragani, R., Flemming, J., Forbes, R., Fuentes, M., Geer, A., Haimberger, L., Healy, S., Hogan, R. J., Hólm, E., Janisková, M., Keeley, S., Laloyaux, P., Lopez, P., Lupu, C., Radnoti, G., de Rosnay, P., Rozum, I., Vamborg, F., Villaume, S., and Thépaut, J.-N.: The ERA5 global reanalysis, Q. J. Roy. Meteor. Soc., 146, 1999–2049, https://doi.org/10.1002/qj.3803, 2020. a
Heslin-Rees, D., Burgos, M., Hansson, H.-C., Krejci, R., Ström, J., Tunved, P., and Zieger, P.: From a polar to a marine environment: has the changing Arctic led to a shift in aerosol light scattering properties?, Atmos. Chem. Phys., 20, 13671–13686, https://doi.org/10.5194/acp-20-13671-2020, 2020. a
Hill, V. L. and Manley, S. L.: Release of reactive bromine and iodine from diatoms and its possible role in halogen transfer in polar and tropical oceans, Limnol. Oceanogr., 54, 812–822, https://doi.org/10.4319/lo.2009.54.3.0812, 2009. a
Igel, A. L., Ekman, A. M., Leck, C., Tjernström, M., Savre, J., and Sedlar, J.: The free troposphere as a potential source of arctic boundary layer aerosol particles, Geophys. Res. Lett., 44, 7053–7060, https://doi.org/10.1002/2017GL073808, 2017. a
Jurányi, Z., Stratmann, F., Herber, A., Wendisch, M., and Borrmann, S.: Master tracks in different resolutions during POLAR 6 campaign P6-247_BACSAM2_2024, PANGAEA [data set], https://doi.org/10.1594/PANGAEA.971763, 2024. a
Jurányi, Z., Lüpkes, C., Stratmann, F., Hartmann, J., Schaefer, J., Jörss, A.-M., Schulz, A., Wetzel, B., Simon, D., Gebhard, E., Stöhr, M., Hofmann, P., Kalmbach, D., Grawe, S., Wendisch, M., and Herber, A.: The T-Bird – a new aircraft-towed instrument platform to measure aerosol properties and turbulence close to the surface: introduction to the aerosol measurement system, Atmos. Meas. Tech., 18, 3477–3494, https://doi.org/10.5194/amt-18-3477-2025, 2025. a
Keil, A. and Wendisch, M.: Bursts of Aitken mode and ultrafine particles observed at the top of continental boundary layer clouds, J. Aerosol Sci., 32, 649–660, https://doi.org/10.1016/S0021-8502(00)00102-6, 2001. a
Kerminen, V.-M., Chen, X., Vakkari, V., Petäjä, T., Kulmala, M., and Bianchi, F.: Atmospheric new particle formation and growth: review of field observations, Environ. Res. Lett., 13, 103003, https://doi.org/10.1088/1748-9326/aadf3c, 2018. a, b
Khadir, T., Riipinen, I., Talvinen, S., Heslin-Rees, D., Pöhlker, C., Rizzo, L., Machado, L. A. T., Franco, M. A., Kremper, L. A., Artaxo, P., Petäjä, T., Kulmala, M., Tunved, P., Ekman, A. M. L., Krejci, R., and Virtanen, A.: Sink, Source or Something In-Between? Net Effects of Precipitation on Aerosol Particle Populations, Geophys. Res. Lett., 50, e2023GL104325, https://doi.org/10.1029/2023GL104325, 2023. a, b
Khosrawi, F., Ström, J., Minikin, A., and Krejci, R.: Particle formation in the Arctic free troposphere during the ASTAR 2004 campaign: a case study on the influence of vertical motion on the binary homogeneous nucleation of H2SO4/H2O, Atmos. Chem. Phys., 10, 1105–1120, https://doi.org/10.5194/acp-10-1105-2010, 2010. a, b, c, d
Kim, K., Yabushita, A., Okumura, M., Saiz-Lopez, A., Cuevas, C. A., Blaszczak-Boxe, C. S., Min, D. W., Yoon, H.-I., and Choi, W.: Production of molecular iodine and tri-iodide in the frozen solution of iodide: implication for polar atmosphere, Environ. Sci. Technol., 50, 1280–1287, https://doi.org/10.1021/acs.est.5b05148, 2016. a
Kirbus, B. and Wendisch, M.: Five-day backwards trajectories at one minute resolution along the flight tracks of the Polar 6 research aircraft during BACSAM II, PANGAEA [data set], https://doi.org/10.1594/PANGAEA.971694, 2024. a
Kulmala, M. and Kerminen, V.-M.: On the formation and growth of atmospheric nanoparticles, Atmos. Res., 90, 132–150, https://doi.org/10.1016/j.atmosres.2008.01.005, 2008. a
Kupiszewski, P., Leck, C., Tjernström, M., Sjogren, S., Sedlar, J., Graus, M., Müller, M., Brooks, B., Swietlicki, E., Norris, S., and Hansel, A.: Vertical profiling of aerosol particles and trace gases over the central Arctic Ocean during summer, Atmos. Chem. Phys., 13, 12405–12431, https://doi.org/10.5194/acp-13-12405-2013, 2013. a, b, c, d
Leaitch, W. R., Sharma, S., Huang, L., Toom-Sauntry, D., Chivulescu, A., Macdonald, A. M., von Salzen, K., Pierce, J. R., Bertram, A. K., Schroder, J. C., Shantz, N. C., Chang, R. Y., and Norman, A.-L.: Dimethyl sulfide control of the clean summertime Arctic aerosol and cloud, Elementa, 1, 000017, https://doi.org/10.12952/journal.elementa.000017, 2013. a, b
Leck, C. and Bigg, E. K.: Aerosol production over remote marine areas-A new route, Geophys. Res. Lett., 26, 3577–3580, https://doi.org/10.1029/1999GL010807, 1999. a
Lee, S.-H., Gordon, H., Yu, H., Lehtipalo, K., Haley, R., Li, Y., and Zhang, R.: New particle formation in the atmosphere: From molecular clusters to global climate, J. Geophys. Res.-Atmos., 124, 7098–7146, https://doi.org/10.1029/2018JD029356, 2019. a
Lonardi, M., Akansu, E. F., Ehrlich, A., Mazzola, M., Pilz, C., Shupe, M. D., Siebert, H., and Wendisch, M.: Tethered balloon-borne observations of thermal-infrared irradiance and cooling rate profiles in the Arctic atmospheric boundary layer, Atmos. Chem. Phys., 24, 1961–1978, https://doi.org/10.5194/acp-24-1961-2024, 2024. a
Mauritsen, T., Sedlar, J., Tjernström, M., Leck, C., Martin, M., Shupe, M., Sjogren, S., Sierau, B., Persson, P. O. G., Brooks, I. M., and Swietlicki, E.: An Arctic CCN-limited cloud-aerosol regime, Atmos. Chem. Phys., 11, 165–173, https://doi.org/10.5194/acp-11-165-2011, 2011. a
McFarquhar, G. M. and Cober, S. G.: Single-scattering properties of mixed-phase Arctic clouds at solar wavelengths: Impacts on radiative transfer, J. Climate, 17, 3799–3813, https://doi.org/10.1175/1520-0442(2004)017<3799:SPOMAC>2.0.CO;2, 2004. a
Merikanto, J., Spracklen, D. V., Mann, G. W., Pickering, S. J., and Carslaw, K. S.: Impact of nucleation on global CCN, Atmos. Chem. Phys., 9, 8601–8616, https://doi.org/10.5194/acp-9-8601-2009, 2009. a
Moser, M., Voigt, C., Jurkat-Witschas, T., Hahn, V., Mioche, G., Jourdan, O., Dupuy, R., Gourbeyre, C., Schwarzenboeck, A., Lucke, J., Boose, Y., Mech, M., Borrmann, S., Ehrlich, A., Herber, A., Lüpkes, C., and Wendisch, M.: Microphysical and thermodynamic phase analyses of Arctic low-level clouds measured above the sea ice and the open ocean in spring and summer, Atmos. Chem. Phys., 23, 7257–7280, https://doi.org/10.5194/acp-23-7257-2023, 2023. a
Perry, K. D. and Hobbs, P. V.: Further evidence for particle nucleation in clear air adjacent to marine cumulus clouds, J. Geophys. Res.-Atmos., 99, 22803–22818, https://doi.org/10.1029/94JD01926, 1994. a
Pierce, J. R. and Adams, P. J.: Uncertainty in global CCN concentrations from uncertain aerosol nucleation and primary emission rates, Atmos. Chem. Phys., 9, 1339–1356, https://doi.org/10.5194/acp-9-1339-2009, 2009. a
Pilz, C., Cassano, J. J., de Boer, G., Kirbus, B., Lonardi, M., Pöhlker, M., Shupe, M. D., Siebert, H., Wendisch, M., and Wehner, B.: Tethered balloon measurements reveal enhanced aerosol occurrence aloft interacting with Arctic low-level clouds, Elementa, 12, https://doi.org/10.1525/elementa.2023.00120, 2024. a, b
Pohorsky, R., Guy, H., Brooks, I. M., Haberstock, L., Fauré, N., Zieger, P., Kojoj, J., Murto, S., Calmer, R., Heutte, B., Lonardi, M., Thomson, E. S., Tjernström, M., Creamean, J., Nenes, A., and Schmale, J.: Contribution of free tropospheric aerosols to Arctic low-level cloud droplets formation and longwave radiative forcing, Atmos. Chem. Phys., 26, 10331–10353, https://doi.org/10.5194/acp-26-10331-2026, 2026. a, b, c, d
Price, R., Baccarini, A., Schmale, J., Zieger, P., Brooks, I. M., Field, P., and Carslaw, K. S.: Late summer transition from a free-tropospheric to boundary layer source of Aitken mode aerosol in the high Arctic, Atmos. Chem. Phys., 23, 2927–2961, https://doi.org/10.5194/acp-23-2927-2023, 2023. a, b, c
Pruppacher, H. R. and Klett, J. D.: Microphysics of clouds and precipitation, https://doi.org/10.1007/978-0-306-48100-0, 2010. a
Raso, A. R. W., Custard, K. D., May, N. W., Tanner, D., Newburn, M. K., Walker, L., Moore, R. J., Huey, L. G., Alexander, L., Shepson, P. B., and Pratt, K. A.: Active molecular iodine photochemistry in the Arctic, P. Natl. Acad. Sci. USA, 114, 10053–10058, https://doi.org/10.1073/pnas.1702803114, 2017. a
Schmale, J. and Baccarini, A.: Progress in unraveling atmospheric new particle formation and growth across the Arctic, Geophys. Res. Lett., 48, e2021GL094198, https://doi.org/10.1029/2021GL094198, 2021. a
Schmale, J., Zieger, P., and Ekman, A. M.: Aerosols in current and future Arctic climate, Nat. Clim. Change, 11, 95–105, https://doi.org/10.1038/s41558-020-00969-5, 2021. a, b, c
Seinfeld, J. H. and Pandis, S. N.: Atmospheric chemistry and physics: from air pollution to climate change, John Wiley & Sons, ISBN 978-0-471-72018-8, 2006. a
Serreze, M. C. and Barry, R. G.: Processes and impacts of Arctic amplification: A research synthesis, Global Planet. Change, 77, 85–96, https://doi.org/10.1016/j.gloplacha.2011.03.004, 2011. a
Serreze, M. C. and Francis, J. A.: The Arctic amplification debate, Climatic Change, 76, 241–264, https://doi.org/10.1007/s10584-005-9017-y, 2006. a
Shupe, M. D., Persson, P. O. G., Brooks, I. M., Tjernström, M., Sedlar, J., Mauritsen, T., Sjogren, S., and Leck, C.: Cloud and boundary layer interactions over the Arctic sea ice in late summer, Atmos. Chem. Phys., 13, 9379–9399, https://doi.org/10.5194/acp-13-9379-2013, 2013. a
Simon, D. J., Schaefer, J., Hartmann, M., Weinhold, K., and Stratmann, F.: Airborne in-situ measurements of aerosol particle number size distributions during the BACSAM II campaign in April 2024, PANGAEA [data set], https://doi.org/10.1594/PANGAEA.993546, 2026. a
Sipilä, M., Sarnela, N., Jokinen, T., Henschel, H., Junninen, H., Kontkanen, J., Richters, S., Kangasluoma, J., Franchin, A., Peräkylä, O., Rissanen, M. P., Ehn, M., Vehkamäki, H., Kurtén, T., Berndt, T., Petäjä, T., Worsnop, D., Ceburnis, D., Kerminen, V.-M., Kulmala, M., and O’Dowd, C.: Molecular-scale evidence of aerosol particle formation via sequential addition of HIO3, Nature, 537, 532–534, https://doi.org/10.1038/nature19314, 2016. a, b
Sprenger, M. and Wernli, H.: The LAGRANTO Lagrangian analysis tool – version 2.0, Geosci. Model Dev., 8, 2569–2586, https://doi.org/10.5194/gmd-8-2569-2015, 2015. a
Stroeve, J., Holland, M. M., Meier, W., Scambos, T., and Serreze, M.: Arctic sea ice decline: Faster than forecast, Geophys. Res. Lett., 34, https://doi.org/10.1029/2007GL029703, 2007. a
von der Weiden, S.-L., Drewnick, F., and Borrmann, S.: Particle Loss Calculator – a new software tool for the assessment of the performance of aerosol inlet systems, Atmos. Meas. Tech., 2, 479–494, https://doi.org/10.5194/amt-2-479-2009, 2009. a
Wallace, J. M. and Hobbs, P. V.: Atmospheric Science: An Introductory Survey, vol. 92 of International Geophysics Series, Elsevier Academic Press, Amsterdam; Boston, 2nd Edn., ISBN 978-0-12-732951-2, 2006. a
Weber, R., Clarke, A., Litchy, M., Li, J., Kok, G., Schillawski, R., and McMurry, P.: Spurious aerosol measurements when sampling from aircraft in the vicinity of clouds, J. Geophys. Res.-Atmos., 103, 28337–28346, https://doi.org/10.1029/98JD02086, 1998. a
Weber, R., Chen, G., Davis, D., Mauldin III, R., Tanner, D., Eisele, F., Clarke, A., Thornton, D., and Bandy, A.: Measurements of enhanced H2SO4 and 3–4 nm particles near a frontal cloud during the First Aerosol Characterization Experiment (ACE 1), J. Geophys. Res.-Atmos., 106, 24107–24117, https://doi.org/10.1029/2000JD000109, 2001. a, b, c
Weber, R., Orsini, D., Wang, B., Scheuer, E., Talbot, R., Dibb, J. E., Seid, G., DeBell, L., Mauldin, R., Kosciuch, E., Cantrell, C., and Eisele, F.: Investigations into free tropospheric new particle formation in the central Canadian arctic during the winter/spring transition as part of TOPSE, J. Geophys. Res.-Atmos., 108, https://doi.org/10.1029/2002JD002239, 2003. a, b, c, d
Wehner, B., Werner, F., Ditas, F., Shaw, R. A., Kulmala, M., and Siebert, H.: Observations of new particle formation in enhanced UV irradiance zones near cumulus clouds, Atmos. Chem. Phys., 15, 11701–11711, https://doi.org/10.5194/acp-15-11701-2015, 2015. a, b
Wendisch, M., Brückner, M., Burrows, J., Crewell, S., Dethloff, K., Ebell, K., Lüpkes, C., Macke, A., Notholt, J., Quaas, J., Rinke, A., and Tegen, I.: Understanding causes and effects of rapid warming in the Arctic, Eos, https://doi.org/10.1029/2017EO064803, 2017. a
Wendisch, M., Brückner, M., Crewell, S., Ehrlich, A., Notholt, J., Lüpkes, C., Macke, A., Burrows, J. P., Rinke, A., Quaas, J., Maturilli, M., Schemann, V., Shupe, M. D., Akansu, E. F., Barrientos-Velasco, C., Bärfuss, K., Blechschmidt, A.-M., Block, K., Bougoudis, I., Bozem, H., Böckmann, C., Bracher, A., Bresson, H., Bretschneider, L., Buschmann, M., Chechin, D. G., Chylik, J., Dahlke, S., Deneke, H., Dethloff, K., Donth, T., Dorn, W., Dupuy, R., Ebell, K., Egerer, U., Engelmann, R., Eppers, O., Gerdes, R., Gierens, R., Gorodetskaya, I. V., Gottschalk, M., Griesche, H., Gryanik, V. M., Handorf, D., Harm-Altstädter, B., Hartmann, J., Hartmann, M., Heinold, B., Herber, A., Herrmann, H., Heygster, G., Höschel, I., Hofmann, Z., Hölemann, J., Hünerbein, A., Jafariserajehlou, S., Jäkel, E., Jacobi, C., Janout, M., Jansen, F., Jourdan, O., Jurányi, Z., Kalesse-Los, H., Kanzow, T., Käthner, R., Kliesch, L. L., Klingebiel, M., Knudsen, E. M., Kovács, T., Körtke, W., Krampe, D., Kretzschmar, J., Kreyling, D., Kulla, B., Kunkel, D., Lampert, A., Lauer, M., Lelli, L., von Lerber, A., Linke, O., Löhnert, U., Lonardi, M., Losa, S. N., Losch, M., Maahn, M., Mech, M., Mei, L., Mertes, S., Metzner, E., Mewes, D., Michaelis, J., Mioche, G., Moser, M., Nakoudi, K., Neggers, R., Neuber, R., Nomokonova, T., Oelker, J., Papakonstantinou-Presvelou, I., Pätzold, F., Pefanis, V., Pohl, C., van Pinxteren, M., Radovan, A., Rhein, M., Rex, M., Richter, A., Risse, N., Ritter, C., Rostosky, P., Rozanov, V. V., Donoso, E. R., Garfias, P. S., Salzmann, M., Schacht, J., Schäfer, M., Schneider, J., Schnierstein, N., Seifert, P., Seo, S., Siebert, H., Soppa, M. A., Spreen, G., Stachlewska, I. S., Stapf, J., Stratmann, F., Tegen, I., Viceto, C., Voigt, C., Vountas, M., Walbröl, A., Walter, M., Wehner, B., Wex, H., Willmes, S., Zanatta, M., and Zeppenfeld, S.: Atmospheric and surface processes, and feedback mechanisms determining Arctic amplification: A review of first results and prospects of the (𝒜𝒞)3 project, B. Am. Meteorol. Soc., 104, E208–E242, https://doi.org/10.1175/BAMS-D-21-0218.1, 2023. a, b, c, d
Wendisch, M., Crewell, S., Ehrlich, A., Herber, A., Kirbus, B., Lüpkes, C., Mech, M., Abel, S. J., Akansu, E. F., Ament, F., Aubry, C., Becker, S., Borrmann, S., Bozem, H., Brückner, M., Clemen, H.-C., Dahlke, S., Dekoutsidis, G., Delanoë, J., De La Torre Castro, E., Dorff, H., Dupuy, R., Eppers, O., Ewald, F., George, G., Gorodetskaya, I. V., Grawe, S., Groß, S., Hartmann, J., Henning, S., Hirsch, L., Jäkel, E., Joppe, P., Jourdan, O., Jurányi, Z., Karalis, M., Kellermann, M., Klingebiel, M., Lonardi, M., Lucke, J., Luebke, A. E., Maahn, M., Maherndl, N., Maturilli, M., Mayer, B., Mayer, J., Mertes, S., Michaelis, J., Michalkov, M., Mioche, G., Moser, M., Müller, H., Neggers, R., Ori, D., Paul, D., Paulus, F. M., Pilz, C., Pithan, F., Pöhlker, M., Pörtge, V., Ringel, M., Risse, N., Roberts, G. C., Rosenburg, S., Röttenbacher, J., Rückert, J., Schäfer, M., Schaefer, J., Schemann, V., Schirmacher, I., Schmidt, J., Schmidt, S., Schneider, J., Schnitt, S., Schwarz, A., Siebert, H., Sodemann, H., Sperzel, T., Spreen, G., Stevens, B., Stratmann, F., Svensson, G., Tatzelt, C., Tuch, T., Vihma, T., Voigt, C., Volkmer, L., Walbröl, A., Weber, A., Wehner, B., Wetzel, B., Wirth, M., and Zinner, T.: Overview: quasi-Lagrangian observations of Arctic air mass transformations – introduction and initial results of the HALO-(AC)3 aircraft campaign, Atmos. Chem. Phys., 24, 8865–8892, https://doi.org/10.5194/acp-24-8865-2024, 2024. a, b
Wendisch, M., Kirbus, B., Ori, D., Shupe, M. D., Crewell, S., Sodemann, H., and Schemann, V.: Observed and modeled Arctic airmass transformations during warm air intrusions and cold air outbreaks, Atmos. Chem. Phys., 25, 15047–15076, https://doi.org/10.5194/acp-25-15047-2025, 2025. a
Wesche, C., Steinhage, D., and Nixdorf, U.: Polar aircraft Polar5 and Polar6 operated by the Alfred Wegener institute, J. Large-Scale Res. Facil., 2, A87–A87, https://doi.org/10.17815/jlsrf-2-153, 2016. a, b
Wiedensohler, A., Covert, D. S., Swietlicki, E., Aalto, P., Heintzenberg, J., and Leck, C.: Occurrence of an ultrafine particle mode less than 20 nm in diameter in the marine boundary layer during Arctic summer and autumn, Tellus B, 48, 213–222, https://doi.org/10.3402/tellusb.v48i2.15887, 1996. a
Wiedensohler, A., Birmili, W., Nowak, A., Sonntag, A., Weinhold, K., Merkel, M., Wehner, B., Tuch, T., Pfeifer, S., Fiebig, M., Fjäraa, A. M., Asmi, E., Sellegri, K., Depuy, R., Venzac, H., Villani, P., Laj, P., Aalto, P., Ogren, J. A., Swietlicki, E., Williams, P., Roldin, P., Quincey, P., Hüglin, C., Fierz-Schmidhauser, R., Gysel, M., Weingartner, E., Riccobono, F., Santos, S., Grüning, C., Faloon, K., Beddows, D., Harrison, R., Monahan, C., Jennings, S. G., O'Dowd, C. D., Marinoni, A., Horn, H.-G., Keck, L., Jiang, J., Scheckman, J., McMurry, P. H., Deng, Z., Zhao, C. S., Moerman, M., Henzing, B., de Leeuw, G., Löschau, G., and Bastian, S.: Mobility particle size spectrometers: harmonization of technical standards and data structure to facilitate high quality long-term observations of atmospheric particle number size distributions, Atmos. Meas. Tech., 5, 657–685, https://doi.org/10.5194/amt-5-657-2012, 2012. a, b
Wiedensohler, A., Wiesner, A., Weinhold, K., Birmili, W., Hermann, M., Merkel, M., Müller, T., Pfeifer, S., Schmidt, A., Tuch, T., Velarde, F., Quincey, P., Seeger, S., and Nowak, A.: Mobility particle size spectrometers: Calibration procedures and measurement uncertainties, Aerosol Sci. Tech., 52, 146–164, https://doi.org/10.1080/02786826.2017.1387229, 2018. a, b
Willis, M. D., Burkart, J., Thomas, J. L., Köllner, F., Schneider, J., Bozem, H., Hoor, P. M., Aliabadi, A. A., Schulz, H., Herber, A. B., Leaitch, W. R., and Abbatt, J. P. D.: Growth of nucleation mode particles in the summertime Arctic: a case study, Atmos. Chem. Phys., 16, 7663–7679, https://doi.org/10.5194/acp-16-7663-2016, 2016. a, b, c
Willis, M. D., Köllner, F., Burkart, J., Bozem, H., Thomas, J. L., Schneider, J., Aliabadi, A. A., Hoor, P. M., Schulz, H., Herber, A. B., Leaitch, W. R., and Abbatt, J. P. D.: Evidence for marine biogenic influence on summertime Arctic aerosol, Geophys. Res. Lett., 44, 6460–6470, https://doi.org/10.1002/2017GL073359, 2017. a, b, c
Willis, M. D., Leaitch, W. R., and Abbatt, J. P.: Processes controlling the composition and abundance of Arctic aerosol, Rev. Geophys., 56, 621–671, https://doi.org/10.1029/2018RG000602, 2018. a, b, c
Wood, R.: Stratocumulus clouds, Mon. Weather Rev., 140, 2373–2423, https://doi.org/10.1175/MWR-D-11-00121.1, 2012. a
Short summary
We investigate the occurrence of newly formed, nanometer-sized aerosol particles in the Arctic atmosphere by analyzing size-resolved particle measurements conducted aboard a research aircraft in April 2024. Vertically-resolved studies on such small particles have remained scarce. We frequently detected newly formed particles at altitudes of up to 4 km. These particles were associated with air mass transport from southern latitudes, the occurrence of clouds, as well as the presence of sea ice.
We investigate the occurrence of newly formed, nanometer-sized aerosol particles in the Arctic...
Altmetrics
Final-revised paper
Preprint