Articles | Volume 18, issue 16
https://doi.org/10.5194/amt-18-3959-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/amt-18-3959-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
25 Aug 2025
Research article |
| 25 Aug 2025
| 25 Aug 2025
A novel aerosol filter sampler for measuring the vertical distribution of ice-nucleating particles via fixed-wing uncrewed aerial vehicles
Alexander Böhmländer
Institute of Meteorology and Climate Research, Karlsruhe Institute of Technology, Karlsruhe, Germany
Larissa Lacher
Institute of Meteorology and Climate Research, Karlsruhe Institute of Technology, Karlsruhe, Germany
David Brus
Atmospheric Composition Research, Finnish Meteorological Institute, Helsinki, Finland
Konstantinos-Matthaios Doulgeris
Atmospheric Composition Research, Finnish Meteorological Institute, Helsinki, Finland
Zoé Brasseur
Institute for Atmospheric and Earth System Research/Physics, Faculty of Science, University of Helsinki, Helsinki, Finland
Matthew Boyer
Institute for Atmospheric and Earth System Research/Physics, Faculty of Science, University of Helsinki, Helsinki, Finland
Joel Kuula
Atmospheric Composition Research, Finnish Meteorological Institute, Helsinki, Finland
Thomas Leisner
Institute of Meteorology and Climate Research, Karlsruhe Institute of Technology, Karlsruhe, Germany
Institute of Meteorology and Climate Research, Karlsruhe Institute of Technology, Karlsruhe, Germany
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Atmos. Meas. Tech., 18, 5321–5348, https://doi.org/10.5194/amt-18-5321-2025, https://doi.org/10.5194/amt-18-5321-2025, 2025
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Water vapor is a strong greenhouse gas, and accurate measurements of its concentration in the upper atmosphere (~8–25 km altitude) are crucial for reliable climate predictions. We investigated the performance of four airborne hygrometers, deployed on aircraft or stratospheric balloon platforms and based on different techniques, in a climate simulation chamber. The results demonstrate the high accuracy and reliability of the involved sensors for atmospheric monitoring and research applications.
David Brus, Viet Le, Joel Kuula, and Konstantinos Doulgeris
Earth Syst. Sci. Data, 17, 5209–5219, https://doi.org/10.5194/essd-17-5209-2025, https://doi.org/10.5194/essd-17-5209-2025, 2025
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This paper provides datasets collected as part of the Pallas Cloud Experiment campaign in northern Finland during autumn of 2022. We provide an overview of a custom-built drone backpack for air quality and atmospheric state variable measurements carried on top of a consumer-grade drone (DJI Mavic 2 Pro). Moreover, we describe the flight strategies and provide an overview of the datasets obtained, including a description of the measurements against a reference for data validation.
Jürgen Gratzl, Alexander Böhmländer, Sanna Pätsi, Clara-E. Pogner, Markus Gorfer, David Brus, Konstantinos Matthaios Doulgeris, Florian Wieland, Eija Asmi, Annika Saarto, Ottmar Möhler, Dominik Stolzenburg, and Hinrich Grothe
Atmos. Chem. Phys., 25, 12007–12035, https://doi.org/10.5194/acp-25-12007-2025, https://doi.org/10.5194/acp-25-12007-2025, 2025
Short summary
Short summary
We studied particles in the air over 1 year in the Finnish sub-Arctic to understand how biological particles affect ice formation in clouds. We found that fungal spores are the main contributors to ice formation at warmer temperatures. These particles are released locally and vary with the weather. Our results also show that we know very little about which fungi can form ice in the atmosphere, highlighting a major gap in our understanding of how nature influences weather and climate.
Larissa Lacher, A. Gannet Hallar, Ian B. McCubbin, Joey Bail, Karl D. Froyd, Justin Jacquot, Xiaoli Shen, Christopher Rapp, Ottmar Möhler, and Daniel Cziczo
EGUsphere, https://doi.org/10.5194/egusphere-2025-4492, https://doi.org/10.5194/egusphere-2025-4492, 2025
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We observe a trend of increasing ice-nucleating particle (INP) concentration in spring in the Rocky Mountains, related to regional dust emissions that may intensify with climate change. Additionally, super-micrometer particles were found as the most important contributors to the INP population. This finding was partly enabled by a novel setup of the Portable Ice Nucleation Experiment (PINE), coupled with a pumped-counterflow virtual impactor allowing for direct analysis of INP properties.
Jürgen Gratzl, David Brus, Konstantinos Doulgeris, Alexander Böhmländer, Ottmar Möhler, and Hinrich Grothe
Earth Syst. Sci. Data, 17, 3975–3985, https://doi.org/10.5194/essd-17-3975-2025, https://doi.org/10.5194/essd-17-3975-2025, 2025
Short summary
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Near-real time monitoring of airborne biological particles like fungal spores or pollen grains is of great interest for two main reasons: to improve atmospheric allergen forecasts and to deepen the understanding of how bio-aerosols influence cloud formation. Here, we measured fluorescent bio-aerosols in the Finnish sub-Arctic with a high time resolution. A data set that might improve our understanding of biosphere–cloud interactions and the dynamics of bio-aerosols in the atmosphere.
Jessica Girdwood, David Brus, Konstantinos-Matthaios Doulgeris, and Alexander Böhmländer
Earth Syst. Sci. Data Discuss., https://doi.org/10.5194/essd-2025-257, https://doi.org/10.5194/essd-2025-257, 2025
Revised manuscript accepted for ESSD
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In-situ data of cloud microphysics is essential for targeted studies of cloud processes, validating remote sensing, and both assessing and improving the accuracy of weather and climate models. In this work we adopt a novel technique using a small uncrewed aircraft (SUA) and a bespoke sensor to produce vertical profiles of cloud microphysical parameters. The data are publicly available from https://zenodo.org/records/14756233.
John Backman, Krista Luoma, Henri Servomaa, Ville Vakkari, and David Brus
Earth Syst. Sci. Data Discuss., https://doi.org/10.5194/essd-2025-284, https://doi.org/10.5194/essd-2025-284, 2025
Preprint under review for ESSD
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This work describes the in-situ aerosol measurements at the Arctic Sammaltunturi measurement station in Pallas in northern Finland. This data paper describes the instruments and the data post processing of key aerosol particle measurements that are relevant for cloud properties. Data reported here are part of the Pallas Cloud Experiment in 2022 (PaCE2022).
Kimmo Teinilä, Sanna Saarikoski, Henna Lintusaari, Teemu Lepistö, Petteri Marjanen, Minna Aurela, Heidi Hellén, Toni Tykkä, Markus Lampimäki, Janne Lampilahti, Luis Barreira, Timo Mäkelä, Leena Kangas, Juha Hatakka, Sami Harni, Joel Kuula, Jarkko V. Niemi, Harri Portin, Jaakko Yli-Ojanperä, Ville Niemelä, Milja Jäppi, Katrianne Lehtipalo, Joonas Vanhanen, Liisa Pirjola, Hanna E. Manninen, Tuukka Petäjä, Topi Rönkkö, and Hilkka Timonen
Atmos. Chem. Phys., 25, 4907–4928, https://doi.org/10.5194/acp-25-4907-2025, https://doi.org/10.5194/acp-25-4907-2025, 2025
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Physical and chemical properties of particulate matter and concentrations of trace gases were measured in a street canyon in Helsinki, Finland, and an urban background site in January–February 2022 to investigate the effect of wintertime conditions on pollutants. State-of-the-art instruments and a mobile laboratory were used, and the measurement data were analysed further with modelling tools like positive matrix factorization and the Pollution Detection Algorithm.
Viet Le, Konstantinos Matthaios Doulgeris, Mika Komppula, John Backman, Gholamhossein Bagheri, Eberhard Bodenschatz, and David Brus
Earth Syst. Sci. Data Discuss., https://doi.org/10.5194/essd-2025-148, https://doi.org/10.5194/essd-2025-148, 2025
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This manuscript presents datasets collected during the Pallas Cloud Experiment in northern Finland during the autumn of 2022. We provide an overview of the payload that measured meteorological, cloud, and aerosol properties, and was deployed on tethered balloon systems across 21 flights. Additionally, we describe the datasets obtained, including details of the instruments on the payload.
Juho Karhu, Tommi Mikkonen, Joel Kuula, Aki Virkkula, Erkki Ikonen, Markku Vainio, Hilkka Timonen, and Tuomas Hieta
Aerosol Research, 3, 113–124, https://doi.org/10.5194/ar-3-113-2025, https://doi.org/10.5194/ar-3-113-2025, 2025
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We present a new photoacoustic instrument for simultaneous measurement of aerosol light absorption at multiple wavelengths. High performance is reached by using an optically read cantilever microphone, which allows for highly sensitive absorption measurements at a compact size. Performance in field conditions is demonstrated with black carbon monitoring at an air quality measurement station, where our results agree well with reference instruments deployed at the site.
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
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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.
Feng Jiang, Harald Saathoff, Uzoamaka Ezenobi, Junwei Song, Hengheng Zhang, Linyu Gao, and Thomas Leisner
Atmos. Chem. Phys., 25, 1917–1930, https://doi.org/10.5194/acp-25-1917-2025, https://doi.org/10.5194/acp-25-1917-2025, 2025
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The chemical composition of brown carbon in the particle and gas phase was determined by mass spectrometry. BrC in the gas phase was mainly controlled by secondary formation and particle-to-gas partitioning. BrC in the particle phase was mainly from secondary formation. This work helps to get a better understanding of diurnal variations and the sources of brown carbon aerosol at a rural location in central Europe.
Paul J. DeMott, Jessica A. Mirrielees, Sarah Suda Petters, Daniel J. Cziczo, Markus D. Petters, Heinz G. Bingemer, Thomas C. J. Hill, Karl Froyd, Sarvesh Garimella, A. Gannet Hallar, Ezra J. T. Levin, Ian B. McCubbin, Anne E. Perring, Christopher N. Rapp, Thea Schiebel, Jann Schrod, Kaitlyn J. Suski, Daniel Weber, Martin J. Wolf, Maria Zawadowicz, Jake Zenker, Ottmar Möhler, and Sarah D. Brooks
Atmos. Meas. Tech., 18, 639–672, https://doi.org/10.5194/amt-18-639-2025, https://doi.org/10.5194/amt-18-639-2025, 2025
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The Fifth International Ice Nucleation Workshop Phase 3 (FIN-03) compared the ambient atmospheric performance of ice-nucleating particle (INP) measuring systems and explored general methods for discerning atmospheric INP compositions. Mirroring laboratory results, INP concentrations agreed within 5–10 factors. Measurements of total aerosol properties and investigations of INP compositions supported a dominant role of soil and plant organic aerosol elements as INPs during the study.
Joel Kuula, Juho Karhu, Tommi Mikkonen, Patrick Grahn, Aki Virkkula, Hilkka Timonen, Tuomas Hieta, and Markku Vainio
Aerosol Research, 3, 1–13, https://doi.org/10.5194/ar-3-1-2025, https://doi.org/10.5194/ar-3-1-2025, 2025
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We developed a new method to measure how particles absorb light as they change in size, which is critical for understanding their climate impact. Our approach uses a sensitive instrument that measures light absorption directly from particles in real time. By pairing this with a device that sorts particles by size, we achieved accurate size-resolved measurements. Our findings closely match theoretical models, offering a promising tool for future research into how particles influence climate.
Junwei Song, Georgios I. Gkatzelis, Ralf Tillmann, Nicolas Brüggemann, Thomas Leisner, and Harald Saathoff
Atmos. Chem. Phys., 24, 13199–13217, https://doi.org/10.5194/acp-24-13199-2024, https://doi.org/10.5194/acp-24-13199-2024, 2024
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Biogenic volatile organic compounds (BVOCs) and organic aerosol (OA) particles were measured online in a stressed spruce-dominated forest. OA was mainly attributed to the monoterpene oxidation products. The mixing ratios of BVOCs were higher than the values previously measured in other temperate forests. The results demonstrate that BVOCs are influenced not only by meteorology and biogenic emissions but also by local anthropogenic emissions and subsequent chemical transformation processes.
Matthew Boyer, Diego Aliaga, Lauriane L. J. Quéléver, Silvia Bucci, Hélène Angot, Lubna Dada, Benjamin Heutte, Lisa Beck, Marina Duetsch, Andreas Stohl, Ivo Beck, Tiia Laurila, Nina Sarnela, Roseline C. Thakur, Branka Miljevic, Markku Kulmala, Tuukka Petäjä, Mikko Sipilä, Julia Schmale, and Tuija Jokinen
Atmos. Chem. Phys., 24, 12595–12621, https://doi.org/10.5194/acp-24-12595-2024, https://doi.org/10.5194/acp-24-12595-2024, 2024
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We analyze the seasonal cycle and sources of gases that are relevant for the formation of aerosol particles in the central Arctic. Since theses gases can form new particles, they can influence Arctic climate. We show that the sources of these gases are associated with changes in the Arctic environment during the year, especially with respect to sea ice. Therefore, the concentration of these gases will likely change in the future as the Arctic continues to warm.
Franziska Vogel, Michael P. Adams, Larissa Lacher, Polly B. Foster, Grace C. E. Porter, Barbara Bertozzi, Kristina Höhler, Julia Schneider, Tobias Schorr, Nsikanabasi S. Umo, Jens Nadolny, Zoé Brasseur, Paavo Heikkilä, Erik S. Thomson, Nicole Büttner, Martin I. Daily, Romy Fösig, Alexander D. Harrison, Jorma Keskinen, Ulrike Proske, Jonathan Duplissy, Markku Kulmala, Tuukka Petäjä, Ottmar Möhler, and Benjamin J. Murray
Atmos. Chem. Phys., 24, 11737–11757, https://doi.org/10.5194/acp-24-11737-2024, https://doi.org/10.5194/acp-24-11737-2024, 2024
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Primary ice formation in clouds strongly influences their properties; hence, it is important to understand the sources of ice-nucleating particles (INPs) and their variability. We present 2 months of INP measurements in a Finnish boreal forest using a new semi-autonomous INP counting device based on gas expansion. These results show strong variability in INP concentrations, and we present a case that the INPs we observe are, at least some of the time, of biological origin.
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
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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.
Xiaoli Shen, David M. Bell, Hugh Coe, Naruki Hiranuma, Fabian Mahrt, Nicholas A. Marsden, Claudia Mohr, Daniel M. Murphy, Harald Saathoff, Johannes Schneider, Jacqueline Wilson, Maria A. Zawadowicz, Alla Zelenyuk, Paul J. DeMott, Ottmar Möhler, and Daniel J. Cziczo
Atmos. Chem. Phys., 24, 10869–10891, https://doi.org/10.5194/acp-24-10869-2024, https://doi.org/10.5194/acp-24-10869-2024, 2024
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Single-particle mass spectrometry (SPMS) is commonly used to measure the chemical composition and mixing state of aerosol particles. Intercomparison of SPMS instruments was conducted. All instruments reported similar size ranges and common spectral features. The instrument-specific detection efficiency was found to be more dependent on particle size than type. All differentiated secondary organic aerosol, soot, and soil dust but had difficulties differentiating among minerals and dusts.
Hengheng Zhang, Wei Huang, Xiaoli Shen, Ramakrishna Ramisetty, Junwei Song, Olga Kiseleva, Christopher Claus Holst, Basit Khan, Thomas Leisner, and Harald Saathoff
Atmos. Chem. Phys., 24, 10617–10637, https://doi.org/10.5194/acp-24-10617-2024, https://doi.org/10.5194/acp-24-10617-2024, 2024
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Our study unravels how stagnant winter conditions elevate aerosol levels in Stuttgart. Cloud cover at night plays a pivotal role, impacting morning air quality. Validating a key model, our findings aid accurate air quality predictions, crucial for effective pollution mitigation in urban areas.
Kunfeng Gao, Franziska Vogel, Romanos Foskinis, Stergios Vratolis, Maria I. Gini, Konstantinos Granakis, Anne-Claire Billault-Roux, Paraskevi Georgakaki, Olga Zografou, Prodromos Fetfatzis, Alexis Berne, Alexandros Papayannis, Konstantinos Eleftheridadis, Ottmar Möhler, and Athanasios Nenes
Atmos. Chem. Phys., 24, 9939–9974, https://doi.org/10.5194/acp-24-9939-2024, https://doi.org/10.5194/acp-24-9939-2024, 2024
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Ice nucleating particle (INP) concentrations are required for correct predictions of clouds and precipitation in a changing climate, but they are poorly constrained in climate models. We unravel source contributions to INPs in the eastern Mediterranean and find that biological particles are important, regardless of their origin. The parameterizations developed exhibit superior performance and enable models to consider biological-particle effects on INPs.
Junwei Song, Harald Saathoff, Feng Jiang, Linyu Gao, Hengheng Zhang, and Thomas Leisner
Atmos. Chem. Phys., 24, 6699–6717, https://doi.org/10.5194/acp-24-6699-2024, https://doi.org/10.5194/acp-24-6699-2024, 2024
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This study presents concurrent online measurements of organic gas and particles (VOCs and OA) at a forested site in summer. Both VOCs and OA were largely contributed by oxygenated organic compounds. Semi-volatile oxygenated OA and organic nitrate formed from monoterpenes and sesquiterpenes contributed significantly to nighttime particle growth. The results help us to understand the causes of nighttime particle growth regularly observed in summer in central European rural forested environments.
Hengheng Zhang, Christian Rolf, Ralf Tillmann, Christian Wesolek, Frank Gunther Wienhold, Thomas Leisner, and Harald Saathoff
Aerosol Research, 2, 135–151, https://doi.org/10.5194/ar-2-135-2024, https://doi.org/10.5194/ar-2-135-2024, 2024
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Our study employs advanced tools, including scanning lidar, balloons, and UAVs, to explore aerosol particles in the atmosphere. The scanning lidar offers distinctive near-ground-level insights, enriching our comprehension of aerosol distribution from ground level to the free troposphere. This research provides valuable data for comparing remote sensing and in situ aerosol measurements, advancing our understanding of aerosol impacts on radiative transfer, clouds, and air quality.
Patrick Grahn and Joel Kuula
EGUsphere, https://doi.org/10.5194/egusphere-2024-1242, https://doi.org/10.5194/egusphere-2024-1242, 2024
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A three-dimensional finite-element based method was used to calculate inertial deposition loss of aerosol particles in flow systems. The method was validated by comparing to known results published in literature. Loss in a geometrically complicated aerosol measurement instrument was calculated and compared to measurements. The method pinpoints the physical locations where particles are lost, which is helpful for improving the performance of aerosol instruments.
Elise K. Wilbourn, Larissa Lacher, Carlos Guerrero, Hemanth S. K. Vepuri, Kristina Höhler, Jens Nadolny, Aidan D. Pantoya, Ottmar Möhler, and Naruki Hiranuma
Atmos. Chem. Phys., 24, 5433–5456, https://doi.org/10.5194/acp-24-5433-2024, https://doi.org/10.5194/acp-24-5433-2024, 2024
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Ambient ice particles were measured at terrestrial and temperate marine sites. Ice particles were more abundant in the former site, while the fraction of ice particles relative to total ambient particles, representing atmospheric ice nucleation efficiency, was higher in the latter site. Ice nucleation parameterizations were developed as a function of examined freezing temperatures from two sites for our study periods (autumn).
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
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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.
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
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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.
Feng Jiang, Kyla Siemens, Claudia Linke, Yanxia Li, Yiwei Gong, Thomas Leisner, Alexander Laskin, and Harald Saathoff
Atmos. Chem. Phys., 24, 2639–2649, https://doi.org/10.5194/acp-24-2639-2024, https://doi.org/10.5194/acp-24-2639-2024, 2024
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We investigated the optical properties, chemical composition, and formation mechanisms of secondary organic aerosol (SOA) and brown carbon (BrC) from the oxidation of indole with and without NO2 in the Aerosol Interaction and Dynamics in the Atmosphere (AIDA) simulation chamber. This work is one of the very few to link the optical properties and chemical composition of indole SOA with and without NO2 by simulation chamber experiments.
Yiwei Gong, Feng Jiang, Yanxia Li, Thomas Leisner, and Harald Saathoff
Atmos. Chem. Phys., 24, 167–184, https://doi.org/10.5194/acp-24-167-2024, https://doi.org/10.5194/acp-24-167-2024, 2024
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This study investigates the role of the important atmospheric reactive intermediates in the formation of dimers and aerosol in monoterpene ozonolysis at different temperatures. Through conducting a series of chamber experiments and utilizing chemical kinetic and aerosol dynamic models, the SOA formation processes are better described, especially for colder regions. The results can be used to improve the chemical mechanism modeling of monoterpenes and SOA parameterization in transport models.
Mohit Singh, Stephanie Helen Jones, Alexei Kiselev, Denis Duft, and Thomas Leisner
Atmos. Meas. Tech., 16, 5205–5215, https://doi.org/10.5194/amt-16-5205-2023, https://doi.org/10.5194/amt-16-5205-2023, 2023
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We introduce a novel method for simultaneous measurement of the viscosity and surface tension of metastable liquids. Our approach is based on the phase analysis of excited shape oscillations in levitated droplets. It is applicable to a wide range of atmospheric conditions and can monitor changes in real time. The technique holds great promise for investigating the effect of atmospheric processing on the viscosity and surface tension of solution droplets in equilibrium with water vapour.
Albert Ansmann, Kevin Ohneiser, Ronny Engelmann, Martin Radenz, Hannes Griesche, Julian Hofer, Dietrich Althausen, Jessie M. Creamean, Matthew C. Boyer, Daniel A. Knopf, Sandro Dahlke, Marion Maturilli, Henriette Gebauer, Johannes Bühl, Cristofer Jimenez, Patric Seifert, and Ulla Wandinger
Atmos. Chem. Phys., 23, 12821–12849, https://doi.org/10.5194/acp-23-12821-2023, https://doi.org/10.5194/acp-23-12821-2023, 2023
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The 1-year MOSAiC (2019–2020) expedition with the German ice breaker Polarstern was the largest polar field campaign ever conducted. The Polarstern, with our lidar aboard, drifted with the pack ice north of 85° N for more than 7 months (October 2019 to mid-May 2020). We measured the full annual cycle of aerosol conditions in terms of aerosol optical and cloud-process-relevant properties. We observed a strong contrast between polluted winter and clean summer aerosol conditions.
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
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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.
Joschka Pfeifer, Naser G. A. Mahfouz, Benjamin C. Schulze, Serge Mathot, Dominik Stolzenburg, Rima Baalbaki, Zoé Brasseur, Lucia Caudillo, Lubna Dada, Manuel Granzin, Xu-Cheng He, Houssni Lamkaddam, Brandon Lopez, Vladimir Makhmutov, Ruby Marten, Bernhard Mentler, Tatjana Müller, Antti Onnela, Maxim Philippov, Ana A. Piedehierro, Birte Rörup, Meredith Schervish, Ping Tian, Nsikanabasi S. Umo, Dongyu S. Wang, Mingyi Wang, Stefan K. Weber, André Welti, Yusheng Wu, Marcel Zauner-Wieczorek, Antonio Amorim, Imad El Haddad, Markku Kulmala, Katrianne Lehtipalo, Tuukka Petäjä, António Tomé, Sander Mirme, Hanna E. Manninen, Neil M. Donahue, Richard C. Flagan, Andreas Kürten, Joachim Curtius, and Jasper Kirkby
Atmos. Chem. Phys., 23, 6703–6718, https://doi.org/10.5194/acp-23-6703-2023, https://doi.org/10.5194/acp-23-6703-2023, 2023
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Attachment rate coefficients between ions and charged aerosol particles determine their lifetimes and may also influence cloud dynamics and aerosol processing. Here we present novel experiments that measure ion–aerosol attachment rate coefficients for multiply charged aerosol particles under atmospheric conditions in the CERN CLOUD chamber. Our results provide experimental discrimination between various theoretical models.
Robert Wagner, Alexander D. James, Victoria L. Frankland, Ottmar Möhler, Benjamin J. Murray, John M. C. Plane, Harald Saathoff, Ralf Weigel, and Martin Schnaiter
Atmos. Chem. Phys., 23, 6789–6811, https://doi.org/10.5194/acp-23-6789-2023, https://doi.org/10.5194/acp-23-6789-2023, 2023
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Polar stratospheric clouds (PSCs) play an important role in the depletion of stratospheric ozone. They can consist of different chemical species, including crystalline nitric acid hydrates. We found that mineral dust or meteoric ablation material can efficiently catalyse the formation of a specific phase of nitric acid dihydrate crystals. We determined predominant particle shapes and infrared optical properties of these crystals, which are important inputs for remote sensing detection of PSCs.
Lucía Caudillo, Mihnea Surdu, Brandon Lopez, Mingyi Wang, Markus Thoma, Steffen Bräkling, Angela Buchholz, Mario Simon, Andrea C. Wagner, Tatjana Müller, Manuel Granzin, Martin Heinritzi, Antonio Amorim, David M. Bell, Zoé Brasseur, Lubna Dada, Jonathan Duplissy, Henning Finkenzeller, Xu-Cheng He, Houssni Lamkaddam, Naser G. A. Mahfouz, Vladimir Makhmutov, Hanna E. Manninen, Guillaume Marie, Ruby Marten, Roy L. Mauldin, Bernhard Mentler, Antti Onnela, Tuukka Petäjä, Joschka Pfeifer, Maxim Philippov, Ana A. Piedehierro, Birte Rörup, Wiebke Scholz, Jiali Shen, Dominik Stolzenburg, Christian Tauber, Ping Tian, António Tomé, Nsikanabasi Silas Umo, Dongyu S. Wang, Yonghong Wang, Stefan K. Weber, André Welti, Marcel Zauner-Wieczorek, Urs Baltensperger, Richard C. Flagan, Armin Hansel, Jasper Kirkby, Markku Kulmala, Katrianne Lehtipalo, Douglas R. Worsnop, Imad El Haddad, Neil M. Donahue, Alexander L. Vogel, Andreas Kürten, and Joachim Curtius
Atmos. Chem. Phys., 23, 6613–6631, https://doi.org/10.5194/acp-23-6613-2023, https://doi.org/10.5194/acp-23-6613-2023, 2023
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In this study, we present an intercomparison of four different techniques for measuring the chemical composition of nanoparticles. The intercomparison was performed based on the observed chemical composition, calculated volatility, and analysis of the thermograms. We found that the methods generally agree on the most important compounds that are found in the nanoparticles. However, they do see different parts of the organic spectrum. We suggest potential explanations for these differences.
Kara D. Lamb, Jerry Y. Harrington, Benjamin W. Clouser, Elisabeth J. Moyer, Laszlo Sarkozy, Volker Ebert, Ottmar Möhler, and Harald Saathoff
Atmos. Chem. Phys., 23, 6043–6064, https://doi.org/10.5194/acp-23-6043-2023, https://doi.org/10.5194/acp-23-6043-2023, 2023
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This study investigates how ice grows directly from vapor in cirrus clouds by comparing observations of populations of ice crystals growing in a cloud chamber against models developed in the context of single-crystal laboratory studies. We demonstrate that previous discrepancies between different experimental measurements do not necessarily point to different physical interpretations but are rather due to assumptions that were made in terms of how experiments were modeled in previous studies.
Konstantinos Matthaios Doulgeris, Ville Vakkari, Ewan J. O'Connor, Veli-Matti Kerminen, Heikki Lihavainen, and David Brus
Atmos. Chem. Phys., 23, 2483–2498, https://doi.org/10.5194/acp-23-2483-2023, https://doi.org/10.5194/acp-23-2483-2023, 2023
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We investigated how different long-range-transported air masses can affect the microphysical properties of low-level clouds in a clean subarctic environment. A connection was revealed. Higher values of cloud droplet number concentrations were related to continental air masses, whereas the lowest values of number concentrations were related to marine air masses. These were characterized by larger cloud droplets. Clouds in all regions were sensitive to increases in cloud number concentration.
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
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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.
Feng Jiang, Junwei Song, Jonas Bauer, Linyu Gao, Magdalena Vallon, Reiner Gebhardt, Thomas Leisner, Stefan Norra, and Harald Saathoff
Atmos. Chem. Phys., 22, 14971–14986, https://doi.org/10.5194/acp-22-14971-2022, https://doi.org/10.5194/acp-22-14971-2022, 2022
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We studied brown carbon aerosol during typical summer and winter periods in downtown Karlsruhe in southwestern Germany. The chromophore and chemical composition of brown carbon was determined by excitation–emission spectroscopy and mass spectrometry. The chromophore types and sources were substantially different in winter and summer. Humic-like chromophores of different degrees of oxidation dominated and were associated with molecules of different molecular weight and nitrogen content.
Outi Meinander, Pavla Dagsson-Waldhauserova, Pavel Amosov, Elena Aseyeva, Cliff Atkins, Alexander Baklanov, Clarissa Baldo, Sarah L. Barr, Barbara Barzycka, Liane G. Benning, Bojan Cvetkovic, Polina Enchilik, Denis Frolov, Santiago Gassó, Konrad Kandler, Nikolay Kasimov, Jan Kavan, James King, Tatyana Koroleva, Viktoria Krupskaya, Markku Kulmala, Monika Kusiak, Hanna K. Lappalainen, Michał Laska, Jerome Lasne, Marek Lewandowski, Bartłomiej Luks, James B. McQuaid, Beatrice Moroni, Benjamin Murray, Ottmar Möhler, Adam Nawrot, Slobodan Nickovic, Norman T. O’Neill, Goran Pejanovic, Olga Popovicheva, Keyvan Ranjbar, Manolis Romanias, Olga Samonova, Alberto Sanchez-Marroquin, Kerstin Schepanski, Ivan Semenkov, Anna Sharapova, Elena Shevnina, Zongbo Shi, Mikhail Sofiev, Frédéric Thevenet, Throstur Thorsteinsson, Mikhail Timofeev, Nsikanabasi Silas Umo, Andreas Uppstu, Darya Urupina, György Varga, Tomasz Werner, Olafur Arnalds, and Ana Vukovic Vimic
Atmos. Chem. Phys., 22, 11889–11930, https://doi.org/10.5194/acp-22-11889-2022, https://doi.org/10.5194/acp-22-11889-2022, 2022
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High-latitude dust (HLD) is a short-lived climate forcer, air pollutant, and nutrient source. Our results suggest a northern HLD belt at 50–58° N in Eurasia and 50–55° N in Canada and at >60° N in Eurasia and >58° N in Canada. Our addition to the previously identified global dust belt (GDB) provides crucially needed information on the extent of active HLD sources with both direct and indirect impacts on climate and environment in remote regions, which are often poorly understood and predicted.
Ivo Beck, Hélène Angot, Andrea Baccarini, Lubna Dada, Lauriane Quéléver, Tuija Jokinen, Tiia Laurila, Markus Lampimäki, Nicolas Bukowiecki, Matthew Boyer, Xianda Gong, Martin Gysel-Beer, Tuukka Petäjä, Jian Wang, and Julia Schmale
Atmos. Meas. Tech., 15, 4195–4224, https://doi.org/10.5194/amt-15-4195-2022, https://doi.org/10.5194/amt-15-4195-2022, 2022
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We present the pollution detection algorithm (PDA), a new method to identify local primary pollution in remote atmospheric aerosol and trace gas time series. The PDA identifies periods of contaminated data and relies only on the target dataset itself; i.e., it is independent of ancillary data such as meteorological variables. The parameters of all pollution identification steps are adjustable so that the PDA can be tuned to different locations and situations. It is available as open-access code.
Rachel Y.-W. Chang, Jonathan P. D. Abbatt, Matthew C. Boyer, Jai Prakash Chaubey, and Douglas B. Collins
Atmos. Chem. Phys., 22, 8059–8071, https://doi.org/10.5194/acp-22-8059-2022, https://doi.org/10.5194/acp-22-8059-2022, 2022
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During summer 2016, the ability of newly formed particles to turn into droplets was measured in the Canadian Arctic. Our observations suggest that these small particles were growing by the condensation of organic vapours likely coming from the surrounding open waters. These particles grew large enough that they could form cloud droplets and therefore affect the earth’s radiation budget. These results are relevant as the Arctic summer rapidly warms with climate change.
Fritz Waitz, Martin Schnaiter, Thomas Leisner, and Emma Järvinen
Atmos. Chem. Phys., 22, 7087–7103, https://doi.org/10.5194/acp-22-7087-2022, https://doi.org/10.5194/acp-22-7087-2022, 2022
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Riming, i.e., the accretion of small droplets on the surface of ice particles via collision, is one of the major uncertainties in model prediction of mixed-phase clouds. We discuss the occurrence (up to 50% of particles) and aging of rimed ice particles and show correlations of the occurrence and the degree of riming with ambient meteorological parameters using data gathered by the Particle Habit Imaging and Polar Scattering (PHIPS) probe during three airborne in situ field campaigns.
Linyu Gao, Junwei Song, Claudia Mohr, Wei Huang, Magdalena Vallon, Feng Jiang, Thomas Leisner, and Harald Saathoff
Atmos. Chem. Phys., 22, 6001–6020, https://doi.org/10.5194/acp-22-6001-2022, https://doi.org/10.5194/acp-22-6001-2022, 2022
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We study secondary organic aerosol (SOA) from β-caryophyllene (BCP) ozonolysis with and without nitrogen oxides over 213–313 K in the simulation chamber. The yields and the rate constants were determined at 243–313 K. Chemical compositions varied at different temperatures, indicating a strong impact on the BCP ozonolysis pathways. This work helps to better understand the SOA from BCP ozonolysis for conditions representative of the real atmosphere from the boundary layer to the upper troposphere.
Zoé Brasseur, Dimitri Castarède, Erik S. Thomson, Michael P. Adams, Saskia Drossaart van Dusseldorp, Paavo Heikkilä, Kimmo Korhonen, Janne Lampilahti, Mikhail Paramonov, Julia Schneider, Franziska Vogel, Yusheng Wu, Jonathan P. D. Abbatt, Nina S. Atanasova, Dennis H. Bamford, Barbara Bertozzi, Matthew Boyer, David Brus, Martin I. Daily, Romy Fösig, Ellen Gute, Alexander D. Harrison, Paula Hietala, Kristina Höhler, Zamin A. Kanji, Jorma Keskinen, Larissa Lacher, Markus Lampimäki, Janne Levula, Antti Manninen, Jens Nadolny, Maija Peltola, Grace C. E. Porter, Pyry Poutanen, Ulrike Proske, Tobias Schorr, Nsikanabasi Silas Umo, János Stenszky, Annele Virtanen, Dmitri Moisseev, Markku Kulmala, Benjamin J. Murray, Tuukka Petäjä, Ottmar Möhler, and Jonathan Duplissy
Atmos. Chem. Phys., 22, 5117–5145, https://doi.org/10.5194/acp-22-5117-2022, https://doi.org/10.5194/acp-22-5117-2022, 2022
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The present measurement report introduces the ice nucleation campaign organized in Hyytiälä, Finland, in 2018 (HyICE-2018). We provide an overview of the campaign settings, and we describe the measurement infrastructure and operating procedures used. In addition, we use results from ice nucleation instrument inter-comparison to show that the suite of these instruments deployed during the campaign reports consistent results.
Joel Kuula, Hilkka Timonen, Jarkko V. Niemi, Hanna E. Manninen, Topi Rönkkö, Tareq Hussein, Pak Lun Fung, Sasu Tarkoma, Mikko Laakso, Erkka Saukko, Aino Ovaska, Markku Kulmala, Ari Karppinen, Lasse Johansson, and Tuukka Petäjä
Atmos. Chem. Phys., 22, 4801–4808, https://doi.org/10.5194/acp-22-4801-2022, https://doi.org/10.5194/acp-22-4801-2022, 2022
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Modern and up-to-date policies and air quality management strategies are instrumental in tackling global air pollution. As the European Union is preparing to revise Ambient Air Quality Directive 2008/50/EC, this paper initiates discussion on selected features of the directive that we believe would benefit from a reassessment. The scientific community has the most recent and deepest understanding of air pollution; thus, its contribution is essential.
Joseph Girdwood, Warren Stanley, Chris Stopford, and David Brus
Atmos. Meas. Tech., 15, 2061–2076, https://doi.org/10.5194/amt-15-2061-2022, https://doi.org/10.5194/amt-15-2061-2022, 2022
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UAVs have great potential to be used for airborne measurements of cloud and aerosol properties, which are of particular importance due to the largely uncharacterised nature of such phenomena. However, since UAVs are a new tool in atmospheric physics expensive platform validation and characterisation of UAV-instrument combinations needs to be performed. This paper presents an evaluation of a fixed-wing UAV in combination with an instrument that measures cloud droplet diameter.
Magdalena Vallon, Linyu Gao, Feng Jiang, Bianca Krumm, Jens Nadolny, Junwei Song, Thomas Leisner, and Harald Saathoff
Atmos. Meas. Tech., 15, 1795–1810, https://doi.org/10.5194/amt-15-1795-2022, https://doi.org/10.5194/amt-15-1795-2022, 2022
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A LED-based light source has been constructed for the AIDA simulation chamber at the Karlsruhe Institute of Technology. It allows aerosol formation and ageing studies under atmospherically relevant illumination intensities and spectral characteristics at temperatures from –90 °C to 30 °C with the possibility of changing the photon flux and irradiation spectrum at any point. The first results of photolysis experiments with 2,3-pentanedione, iron oxalate and a brown carbon component are shown.
Konstantinos Matthaios Doulgeris, Heikki Lihavainen, Anti-Pekka Hyvärinen, Veli-Matti Kerminen, and David Brus
Earth Syst. Sci. Data, 14, 637–649, https://doi.org/10.5194/essd-14-637-2022, https://doi.org/10.5194/essd-14-637-2022, 2022
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We produced and summarized data sets obtained from two cloud ground-based spectrometers (CAPS and FSSP-100 ground setups) during 8 years of Pallas Cloud Experiment campaigns conducted in autumn from 2004 until 2019 along with several meteorological variables. The campaigns took place in the Finnish sub-Arctic region in a clear environment in temperatures that were usually below zero. This data set provides a helpful contribution to cloud microphysics processes.
Pak Lun Fung, Martha A. Zaidan, Jarkko V. Niemi, Erkka Saukko, Hilkka Timonen, Anu Kousa, Joel Kuula, Topi Rönkkö, Ari Karppinen, Sasu Tarkoma, Markku Kulmala, Tuukka Petäjä, and Tareq Hussein
Atmos. Chem. Phys., 22, 1861–1882, https://doi.org/10.5194/acp-22-1861-2022, https://doi.org/10.5194/acp-22-1861-2022, 2022
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We developed an input-adaptive mixed-effects model, which was automatised to select the best combination of input variables, including up to three fixed effect variables and three time indictors as random effect variables. We tested the model to estimate lung-deposited surface area (LDSA), which correlates well with human health. The results show the inclusion of time indicators improved the sensitivity and the accuracy of the model so that it could serve as a network of virtual sensors.
Manuel Baumgartner, Christian Rolf, Jens-Uwe Grooß, Julia Schneider, Tobias Schorr, Ottmar Möhler, Peter Spichtinger, and Martina Krämer
Atmos. Chem. Phys., 22, 65–91, https://doi.org/10.5194/acp-22-65-2022, https://doi.org/10.5194/acp-22-65-2022, 2022
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An important mechanism for the appearance of ice particles in the upper troposphere at low temperatures is homogeneous nucleation. This process is commonly described by the
Koop line, predicting the humidity at freezing. However, laboratory measurements suggest that the freezing humidities are above the Koop line, motivating the present study to investigate the influence of different physical parameterizations on the homogeneous freezing with the help of a detailed numerical model.
Lucía Caudillo, Birte Rörup, Martin Heinritzi, Guillaume Marie, Mario Simon, Andrea C. Wagner, Tatjana Müller, Manuel Granzin, Antonio Amorim, Farnoush Ataei, Rima Baalbaki, Barbara Bertozzi, Zoé Brasseur, Randall Chiu, Biwu Chu, Lubna Dada, Jonathan Duplissy, Henning Finkenzeller, Loïc Gonzalez Carracedo, Xu-Cheng He, Victoria Hofbauer, Weimeng Kong, Houssni Lamkaddam, Chuan P. Lee, Brandon Lopez, Naser G. A. Mahfouz, Vladimir Makhmutov, Hanna E. Manninen, Ruby Marten, Dario Massabò, Roy L. Mauldin, Bernhard Mentler, Ugo Molteni, Antti Onnela, Joschka Pfeifer, Maxim Philippov, Ana A. Piedehierro, Meredith Schervish, Wiebke Scholz, Benjamin Schulze, Jiali Shen, Dominik Stolzenburg, Yuri Stozhkov, Mihnea Surdu, Christian Tauber, Yee Jun Tham, Ping Tian, António Tomé, Steffen Vogt, Mingyi Wang, Dongyu S. Wang, Stefan K. Weber, André Welti, Wang Yonghong, Wu Yusheng, Marcel Zauner-Wieczorek, Urs Baltensperger, Imad El Haddad, Richard C. Flagan, Armin Hansel, Kristina Höhler, Jasper Kirkby, Markku Kulmala, Katrianne Lehtipalo, Ottmar Möhler, Harald Saathoff, Rainer Volkamer, Paul M. Winkler, Neil M. Donahue, Andreas Kürten, and Joachim Curtius
Atmos. Chem. Phys., 21, 17099–17114, https://doi.org/10.5194/acp-21-17099-2021, https://doi.org/10.5194/acp-21-17099-2021, 2021
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We performed experiments in the CLOUD chamber at CERN at low temperatures to simulate new particle formation in the upper free troposphere (at −30 ºC and −50 ºC). We measured the particle and gas phase and found that most of the compounds present in the gas phase are detected as well in the particle phase. The major compounds in the particles are C8–10 and C18–20. Specifically, we showed that C5 and C15 compounds are detected in a mixed system with isoprene and α-pinene at −30 ºC, 20 % RH.
Larissa Lacher, Hans-Christian Clemen, Xiaoli Shen, Stephan Mertes, Martin Gysel-Beer, Alireza Moallemi, Martin Steinbacher, Stephan Henne, Harald Saathoff, Ottmar Möhler, Kristina Höhler, Thea Schiebel, Daniel Weber, Jann Schrod, Johannes Schneider, and Zamin A. Kanji
Atmos. Chem. Phys., 21, 16925–16953, https://doi.org/10.5194/acp-21-16925-2021, https://doi.org/10.5194/acp-21-16925-2021, 2021
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We investigate ice-nucleating particle properties at Jungfraujoch during the 2017 joint INUIT/CLACE field campaign, to improve the knowledge about those rare particles in a cloud-relevant environment. By quantifying ice-nucleating particles in parallel to single-particle mass spectrometry measurements, we find that mineral dust and aged sea spray particles are potential candidates for ice-nucleating particles. Our findings are supported by ice residual analysis and source region modeling.
Ulrich Platt, Thomas Wagner, Jonas Kuhn, and Thomas Leisner
Atmos. Meas. Tech., 14, 6867–6883, https://doi.org/10.5194/amt-14-6867-2021, https://doi.org/10.5194/amt-14-6867-2021, 2021
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Absorption spectroscopy of scattered sunlight is extremely useful for the analysis of atmospheric trace gas distributions. A central parameter for the achievable sensitivity of spectroscopic instruments is the light throughput, which can be enhanced in a number of ways. We present new ideas and considerations of how instruments could be optimized. Particular emphasis is on arrays of massively parallel instruments. Such arrays can reduce the size and weight of instruments by orders of magnitude.
Haoran Li, Ottmar Möhler, Tuukka Petäjä, and Dmitri Moisseev
Atmos. Chem. Phys., 21, 14671–14686, https://doi.org/10.5194/acp-21-14671-2021, https://doi.org/10.5194/acp-21-14671-2021, 2021
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In natural clouds, ice-nucleating particles are expected to be rare above –10 °C. In the current paper, we found that the formation of ice columns is frequent in stratiform clouds and is associated with increased precipitation intensity and liquid water path. In single-layer shallow clouds, the production of ice columns was attributed to secondary ice production, despite the rime-splintering process not being expected to take place in such clouds.
Julia Schneider, Kristina Höhler, Robert Wagner, Harald Saathoff, Martin Schnaiter, Tobias Schorr, Isabelle Steinke, Stefan Benz, Manuel Baumgartner, Christian Rolf, Martina Krämer, Thomas Leisner, and Ottmar Möhler
Atmos. Chem. Phys., 21, 14403–14425, https://doi.org/10.5194/acp-21-14403-2021, https://doi.org/10.5194/acp-21-14403-2021, 2021
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Homogeneous freezing is a relevant mechanism for the formation of cirrus clouds in the upper troposphere. Based on an extensive set of homogeneous freezing experiments at the AIDA chamber with aqueous sulfuric acid aerosol, we provide a new fit line for homogeneous freezing onset conditions of sulfuric acid aerosol focusing on cirrus temperatures. In the atmosphere, homogeneous freezing thresholds have important implications on the cirrus cloud occurrence and related cloud radiative effects.
Naruki Hiranuma, Brent W. Auvermann, Franco Belosi, Jack Bush, Kimberly M. Cory, Dimitrios G. Georgakopoulos, Kristina Höhler, Yidi Hou, Larissa Lacher, Harald Saathoff, Gianni Santachiara, Xiaoli Shen, Isabelle Steinke, Romy Ullrich, Nsikanabasi S. Umo, Hemanth S. K. Vepuri, Franziska Vogel, and Ottmar Möhler
Atmos. Chem. Phys., 21, 14215–14234, https://doi.org/10.5194/acp-21-14215-2021, https://doi.org/10.5194/acp-21-14215-2021, 2021
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We present laboratory and field studies showing that an open-lot livestock facility is a substantial source of atmospheric ice-nucleating particles (INPs). The ambient concentration of INPs from livestock facilities in Texas is very high. It is up to several thousand INPs per liter below –20 °C and may impact regional aerosol–cloud interactions. About 50% of feedlot INPs were supermicron in diameter. No notable amount of known ice-nucleating microorganisms was found in our feedlot samples.
Robert Wagner, Luisa Ickes, Allan K. Bertram, Nora Els, Elena Gorokhova, Ottmar Möhler, Benjamin J. Murray, Nsikanabasi Silas Umo, and Matthew E. Salter
Atmos. Chem. Phys., 21, 13903–13930, https://doi.org/10.5194/acp-21-13903-2021, https://doi.org/10.5194/acp-21-13903-2021, 2021
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Sea spray aerosol particles are a mixture of inorganic salts and organic matter from phytoplankton organisms. At low temperatures in the upper troposphere, both inorganic and organic constituents can induce the formation of ice crystals and thereby impact cloud properties and climate. In this study, we performed experiments in a cloud simulation chamber with particles produced from Arctic seawater samples to quantify the relative contribution of inorganic and organic species in ice formation.
Alexei A. Kiselev, Alice Keinert, Tilia Gaedeke, Thomas Leisner, Christoph Sutter, Elena Petrishcheva, and Rainer Abart
Atmos. Chem. Phys., 21, 11801–11814, https://doi.org/10.5194/acp-21-11801-2021, https://doi.org/10.5194/acp-21-11801-2021, 2021
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Alkali feldspar is the most abundant mineral in the Earth's crust and is often present in mineral dust aerosols that are responsible for the formation of rain and snow in clouds. However, the cloud droplets containing pure potassium-rich feldspar would not freeze unless cooled down to a very low temperature. Here we show that partly replacing potassium with sodium would induce fracturing of feldspar, exposing a crystalline surface that could initiate freezing at higher temperature.
Hengheng Zhang, Frank Wagner, Harald Saathoff, Heike Vogel, Gholam Ali Hoshyaripour, Vanessa Bachmann, Jochen Förstner, and Thomas Leisner
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2021-193, https://doi.org/10.5194/amt-2021-193, 2021
Revised manuscript not accepted
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The evolution and the properties of Saharan dust plume were characterized by LIDARs, a sun photometer, and a regional transport model. Comparison between LIDAR measurements, sun photometer and ICON-ART predictions shows a good agreement for dust arrival time, dust layer height, and dust structure but also that the model overestimates the backscatter coefficients by a factor of (2.2 ± 0.16) and underestimate aerosol optical depth by a factor of (1.5 ± 0.11).
Michael P. Adams, Nina S. Atanasova, Svetlana Sofieva, Janne Ravantti, Aino Heikkinen, Zoé Brasseur, Jonathan Duplissy, Dennis H. Bamford, and Benjamin J. Murray
Biogeosciences, 18, 4431–4444, https://doi.org/10.5194/bg-18-4431-2021, https://doi.org/10.5194/bg-18-4431-2021, 2021
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The formation of ice in clouds is critically important for the planet's climate. Hence, we need to know which aerosol types nucleate ice and how effectively they do so. Here we show that virus particles, with a range of architectures, nucleate ice when immersed in supercooled water. However, we also show that they only make a minor contribution to the ice-nucleating particle population in the terrestrial atmosphere, but we cannot rule them out as being important in the marine environment.
Barbara Bertozzi, Robert Wagner, Junwei Song, Kristina Höhler, Joschka Pfeifer, Harald Saathoff, Thomas Leisner, and Ottmar Möhler
Atmos. Chem. Phys., 21, 10779–10798, https://doi.org/10.5194/acp-21-10779-2021, https://doi.org/10.5194/acp-21-10779-2021, 2021
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Internally mixed particles composed of sulfate and organics are among the most abundant aerosol types. Their ice nucleation (IN) ability influences the formation of cirrus and, thus, the climate. We show that the presence of a thin organic coating suppresses the heterogeneous IN ability of crystalline ammonium sulfate particles. However, the IN ability of the same particle can substantially change if subjected to atmospheric processing, mainly due to differences in the resulting morphology.
David Brus, Jani Gustafsson, Osku Kemppinen, Gijs de Boer, and Anne Hirsikko
Earth Syst. Sci. Data, 13, 2909–2922, https://doi.org/10.5194/essd-13-2909-2021, https://doi.org/10.5194/essd-13-2909-2021, 2021
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This publication summarizes measurements collected and datasets generated by the Finnish Meteorological Institute and Kansas State University teams during the LAPSE-RATE campaign that took place in San Luis Valley, Colorado, during summer 2018. We provide an overview of the rotorcraft and offer insights into the payloads that were used. We describe the teams’ scientific goals, flight strategies, and the datasets, including a description of the measurement validation techniques applied.
Fritz Waitz, Martin Schnaiter, Thomas Leisner, and Emma Järvinen
Atmos. Meas. Tech., 14, 3049–3070, https://doi.org/10.5194/amt-14-3049-2021, https://doi.org/10.5194/amt-14-3049-2021, 2021
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A major challenge in the observations of mixed-phase clouds remains the phase discrimination and sizing of cloud droplets and ice crystals, especially for particles with diameters smaller than 0.1 mm. Here, we present a new method to derive the phase and size of single cloud particles using their angular-light-scattering information. Comparisons with other in situ instruments in three case studies show good agreement.
Julia Schneider, Kristina Höhler, Paavo Heikkilä, Jorma Keskinen, Barbara Bertozzi, Pia Bogert, Tobias Schorr, Nsikanabasi Silas Umo, Franziska Vogel, Zoé Brasseur, Yusheng Wu, Simo Hakala, Jonathan Duplissy, Dmitri Moisseev, Markku Kulmala, Michael P. Adams, Benjamin J. Murray, Kimmo Korhonen, Liqing Hao, Erik S. Thomson, Dimitri Castarède, Thomas Leisner, Tuukka Petäjä, and Ottmar Möhler
Atmos. Chem. Phys., 21, 3899–3918, https://doi.org/10.5194/acp-21-3899-2021, https://doi.org/10.5194/acp-21-3899-2021, 2021
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By triggering the formation of ice crystals, ice-nucleating particles (INP) strongly influence cloud formation. Continuous, long-term measurements are needed to characterize the atmospheric INP variability. Here, a first long-term time series of INP spectra measured in the boreal forest for more than 1 year is presented, showing a clear seasonal cycle. It is shown that the seasonal dependency of INP concentrations and prevalent INP types is driven by the abundance of biogenic aerosol.
Robert Wagner, Baptiste Testa, Michael Höpfner, Alexei Kiselev, Ottmar Möhler, Harald Saathoff, Jörn Ungermann, and Thomas Leisner
Atmos. Meas. Tech., 14, 1977–1991, https://doi.org/10.5194/amt-14-1977-2021, https://doi.org/10.5194/amt-14-1977-2021, 2021
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During the Asian summer monsoon period, air pollutants are transported from layers near the ground to high altitudes of 13 to 18 km in the atmosphere. Infrared measurements have shown that particles composed of solid ammonium nitrate are a major part of these pollutants. To enable the quantitative analysis of the infrared spectra, we have determined for the first time accurate optical constants of ammonium nitrate for the low-temperature conditions of the upper atmosphere.
Sami D. Seppälä, Joel Kuula, Antti-Pekka Hyvärinen, Sanna Saarikoski, Topi Rönkkö, Jorma Keskinen, Jukka-Pekka Jalkanen, and Hilkka Timonen
Atmos. Chem. Phys., 21, 3215–3234, https://doi.org/10.5194/acp-21-3215-2021, https://doi.org/10.5194/acp-21-3215-2021, 2021
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The effects of fuel sulfur content restrictions implemented by the International Maritime Organization in the Baltic Sea (in July 2010 and January 2015) on the particle properties of ship exhaust plumes and ambient aerosol were studied. The restrictions reduced the particle number concentrations and median particle size in plumes and number concentrations in ambient aerosol. These changes may improve human health in coastal areas and decrease the cooling effect of exhaust emissions from ships.
Ottmar Möhler, Michael Adams, Larissa Lacher, Franziska Vogel, Jens Nadolny, Romy Ullrich, Cristian Boffo, Tatjana Pfeuffer, Achim Hobl, Maximilian Weiß, Hemanth S. K. Vepuri, Naruki Hiranuma, and Benjamin J. Murray
Atmos. Meas. Tech., 14, 1143–1166, https://doi.org/10.5194/amt-14-1143-2021, https://doi.org/10.5194/amt-14-1143-2021, 2021
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The Earth's climate is influenced by clouds, which are impacted by ice-nucleating particles (INPs), a minor fraction of atmospheric aerosols. INPs induce ice formation in clouds and thus often initiate precipitation formation. The Portable Ice Nucleation Experiment (PINE) is the first fully automated instrument to study cloud ice formation and to obtain long-term records of INPs. This is a timely development, and the capabilities it offers for research and atmospheric monitoring are significant.
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Short summary
Clouds and aerosol are important for weather and climate. Typically, pure water cloud droplets stay liquid until around −35 °C, unless they come into contact with ice-nucleating particles (INPs). INPs are a rare subset of aerosol particles. Using uncrewed aerial vehicles (UAVs), it is possible to collect aerosol particles and analyse their ice-nucleating ability. This study describes the test and validation of a sampling set-up that can be used to collect aerosol particles onto a filter.
Clouds and aerosol are important for weather and climate. Typically, pure water cloud droplets...
