Articles | Volume 16, issue 15
https://doi.org/10.5194/amt-16-3653-2023
© Author(s) 2023. 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-16-3653-2023
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
08 Aug 2023
Research article |
| 08 Aug 2023
| 08 Aug 2023
Concept, absolute calibration, and validation of a new benchtop laser imaging polar nephelometer
Alireza Moallemi
Laboratory of Atmospheric Chemistry, Paul Scherrer Institute (PSI), 5232 Villigen, Switzerland
now at: Extreme Environments Research Lab (EPFL), School of Architecture, Civil and Environmental Engineering, EPFL, Sion, Switzerland
Robin L. Modini
Laboratory of Atmospheric Chemistry, Paul Scherrer Institute (PSI), 5232 Villigen, Switzerland
Benjamin T. Brem
Laboratory of Atmospheric Chemistry, Paul Scherrer Institute (PSI), 5232 Villigen, Switzerland
Barbara Bertozzi
Laboratory of Atmospheric Chemistry, Paul Scherrer Institute (PSI), 5232 Villigen, Switzerland
Philippe Giaccari
Micos Engineering GmbH, 8600 Dübendorf, Switzerland
Laboratory of Atmospheric Chemistry, Paul Scherrer Institute (PSI), 5232 Villigen, Switzerland
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Lubna Dada, Benjamin T. Brem, Lidia-Marta Amarandi-Netedu, Martine Collaud Coen, Nikolaos Evangeliou, Christoph Hueglin, Nora Nowak, Robin Modini, Martin Steinbacher, and Martin Gysel-Beer
Aerosol Research, 3, 315–336, https://doi.org/10.5194/ar-3-315-2025, https://doi.org/10.5194/ar-3-315-2025, 2025
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We investigated the sources of ultrafine particles (UFPs) in Payerne, Switzerland, highlighting the significant role of secondary processes in elevating UFP concentrations to levels comparable to urban areas. As the first study in rural midland Switzerland to analyze new particle formation events and secondary contributions, it offers key insights for air quality regulation and the role of agriculture in Switzerland and central Europe.
Tiantian Wang, Jun Zhang, Houssni Lamkaddam, Kun Li, Ka Yuen Cheung, Lisa Kattner, Erlend Gammelsæter, Michael Bauer, Zachary C. J. Decker, Deepika Bhattu, Rujin Huang, Rob L. Modini, Jay G. Slowik, Imad El Haddad, Andre S. H. Prevot, and David M. Bell
Atmos. Chem. Phys., 25, 2707–2724, https://doi.org/10.5194/acp-25-2707-2025, https://doi.org/10.5194/acp-25-2707-2025, 2025
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Our study analyzes real-time emissions of organic vapors from solid fuel combustion. Using the mass spectrometer, we tested various fuels, finding higher emission factors for organic vapors from wood burning. Intermediate-volatility organic compounds constituted a significant fraction of emissions in solid fuel combustion. Statistical tests identified unique potential markers. Our insights benefit air quality, climate, and health, aiding accurate emission assessments.
Imad El Haddad, Danielle Vienneau, Kaspar R. Daellenbach, Robin Modini, Jay G. Slowik, Abhishek Upadhyay, Petros N. Vasilakos, David Bell, Kees de Hoogh, and Andre S. H. Prevot
Atmos. Chem. Phys., 24, 11981–12011, https://doi.org/10.5194/acp-24-11981-2024, https://doi.org/10.5194/acp-24-11981-2024, 2024
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This opinion paper explores how advances in aerosol science inform our understanding of the health impacts of outdoor particulate pollution. We advocate for a shift in the way we target PM pollution, focusing on the most harmful anthropogenic emissions. We highlight key observations, modelling developments, and emission measurements needed to achieve this shift.
Valeria Mardoñez-Balderrama, Griša Močnik, Marco Pandolfi, Robin L. Modini, Fernando Velarde, Laura Renzi, Angela Marinoni, Jean-Luc Jaffrezo, Isabel Moreno R., Diego Aliaga, Federico Bianchi, Claudia Mohr, Martin Gysel-Beer, Patrick Ginot, Radovan Krejci, Alfred Wiedensohler, Gaëlle Uzu, Marcos Andrade, and Paolo Laj
Atmos. Chem. Phys., 24, 12055–12077, https://doi.org/10.5194/acp-24-12055-2024, https://doi.org/10.5194/acp-24-12055-2024, 2024
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Levels of black carbon (BC) are scarcely reported in the Southern Hemisphere, especially in high-altitude conditions. This study provides insight into the concentration level, variability, and optical properties of BC in La Paz and El Alto and at the Chacaltaya Global Atmosphere Watch Station. Two methods of source apportionment of absorption were tested and compared showing traffic as the main contributor to absorption in the urban area, in addition to biomass and open waste burning.
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.
Timothy A. Sipkens, Joel C. Corbin, Brett Smith, Stéphanie Gagné, Prem Lobo, Benjamin T. Brem, Mark P. Johnson, and Gregory J. Smallwood
Atmos. Meas. Tech., 17, 4291–4302, https://doi.org/10.5194/amt-17-4291-2024, https://doi.org/10.5194/amt-17-4291-2024, 2024
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Carbonaceous particles, such as soot, contribute to climate forcing, air pollution, and human health impacts. Thermal–optical analysis is a calibration standard used to measure these particles, but significant differences have been observed in the measurements across identical instruments. We report on the reproducibility of these measurements for aircraft emissions, which range from 8.0 % of the nominal value for organic carbon to 17 % for elemental carbon.
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.
Christina Spitieri, Maria Gini, Martin Gysel-Beer, and Konstantinos Eleftheriadis
Atmos. Chem. Phys., 23, 235–249, https://doi.org/10.5194/acp-23-235-2023, https://doi.org/10.5194/acp-23-235-2023, 2023
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The paper provides insights into the hygroscopic properties and state of mixing of atmospheric aerosol through 1 year of measurements of key microphysical parameters in the suburbs of the most densely populated city of Greece, Athens, in the eastern Mediterranean, which is considered an important climate change hotspot. The results can be used for the prediction of cloud condensation nuclei and quantification of the influence of ambient relative humidity on light scattering by aerosol particles.
Alireza Moallemi, Rob L. Modini, Tatyana Lapyonok, Anton Lopatin, David Fuertes, Oleg Dubovik, Philippe Giaccari, and Martin Gysel-Beer
Atmos. Meas. Tech., 15, 5619–5642, https://doi.org/10.5194/amt-15-5619-2022, https://doi.org/10.5194/amt-15-5619-2022, 2022
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Aerosol properties (size distributions, refractive indices) can be retrieved from in situ, angularly resolved light scattering measurements performed with polar nephelometers. We apply an established framework to assess the aerosol property retrieval potential for different instrument configurations, target applications, and assumed prior knowledge. We also demonstrate how a reductive greedy algorithm can be used to determine the optimal placements of the angular sensors in a polar nephelometer.
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
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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.
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.
Cyril Brunner, Benjamin T. Brem, Martine Collaud Coen, Franz Conen, Martin Steinbacher, Martin Gysel-Beer, and Zamin A. Kanji
Atmos. Chem. Phys., 22, 7557–7573, https://doi.org/10.5194/acp-22-7557-2022, https://doi.org/10.5194/acp-22-7557-2022, 2022
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Microscopic particles called ice-nucleating particles (INPs) are essential for ice crystals to form in clouds. INPs are a tiny proportion of atmospheric aerosol, and their abundance is poorly constrained. We study how the concentration of INPs changes diurnally and seasonally at a mountaintop station in central Europe. Unsurprisingly, a diurnal cycle is only found when considering air masses that have had lower-altitude ground contact. The highest INP concentrations occur in spring.
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.
Dalrin Ampritta Amaladhasan, Claudia Heyn, Christopher R. Hoyle, Imad El Haddad, Miriam Elser, Simone M. Pieber, Jay G. Slowik, Antonio Amorim, Jonathan Duplissy, Sebastian Ehrhart, Vladimir Makhmutov, Ugo Molteni, Matti Rissanen, Yuri Stozhkov, Robert Wagner, Armin Hansel, Jasper Kirkby, Neil M. Donahue, Rainer Volkamer, Urs Baltensperger, Martin Gysel-Beer, and Andreas Zuend
Atmos. Chem. Phys., 22, 215–244, https://doi.org/10.5194/acp-22-215-2022, https://doi.org/10.5194/acp-22-215-2022, 2022
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We use a combination of models for gas-phase chemical reactions and equilibrium gas–particle partitioning of isoprene-derived secondary organic aerosols (SOAs) informed by dark ozonolysis experiments conducted in the CLOUD chamber. Our predictions cover high to low relative humidities (RHs) and quantify how SOA mass yields are enhanced at high RH as well as the impact of inorganic seeds of distinct hygroscopicities and acidities on the coupled partitioning of water and semi-volatile organics.
Cyril Brunner, Benjamin T. Brem, Martine Collaud Coen, Franz Conen, Maxime Hervo, Stephan Henne, Martin Steinbacher, Martin Gysel-Beer, and Zamin A. Kanji
Atmos. Chem. Phys., 21, 18029–18053, https://doi.org/10.5194/acp-21-18029-2021, https://doi.org/10.5194/acp-21-18029-2021, 2021
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Special microscopic particles called ice-nucleating particles (INPs) are essential for ice crystals to form in the atmosphere. INPs are sparse and their atmospheric concentration and properties are not well understood. Mineral dust particles make up a significant fraction of INPs but how much remains unknown. Here, we address this knowledge gap by studying periods when mineral particles are present in large quantities at a mountaintop station in central Europe.
Gian Lieberherr, Kevin Auderset, Bertrand Calpini, Bernard Clot, Benoît Crouzy, Martin Gysel-Beer, Thomas Konzelmann, José Manzano, Andrea Mihajlovic, Alireza Moallemi, David O'Connor, Branko Sikoparija, Eric Sauvageat, Fiona Tummon, and Konstantina Vasilatou
Atmos. Meas. Tech., 14, 7693–7706, https://doi.org/10.5194/amt-14-7693-2021, https://doi.org/10.5194/amt-14-7693-2021, 2021
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Today there is no standard procedure to validate bioaerosol and pollen monitors. Three instruments were tested, focusing on detecting particles of different sizes. Only one instrument was able to detect the smallest particles (0.5 µm Ø), whereas the others performed best at the largest tested particles (10 µm Ø). These results are the first step towards a standardised validation procedure. The need for a reference counting method for larger particles (pollen grains: 10–200 µm Ø) was emphasised.
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
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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
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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.
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.
Sebastian Düsing, Albert Ansmann, Holger Baars, Joel C. Corbin, Cyrielle Denjean, Martin Gysel-Beer, Thomas Müller, Laurent Poulain, Holger Siebert, Gerald Spindler, Thomas Tuch, Birgit Wehner, and Alfred Wiedensohler
Atmos. Chem. Phys., 21, 16745–16773, https://doi.org/10.5194/acp-21-16745-2021, https://doi.org/10.5194/acp-21-16745-2021, 2021
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The work deals with optical properties of aerosol particles in dried and atmospheric states. Based on two measurement campaigns in the rural background of central Europe, different measurement approaches were compared with each other, such as modeling based on Mie theory and direct in situ or remote sensing measurements. Among others, it was shown that the aerosol extinction-to-backscatter ratio is relative humidity dependent, and refinement with respect to the model input parameters is needed.
Vaios Moschos, Martin Gysel-Beer, Robin L. Modini, Joel C. Corbin, Dario Massabò, Camilla Costa, Silvia G. Danelli, Athanasia Vlachou, Kaspar R. Daellenbach, Sönke Szidat, Paolo Prati, André S. H. Prévôt, Urs Baltensperger, and Imad El Haddad
Atmos. Chem. Phys., 21, 12809–12833, https://doi.org/10.5194/acp-21-12809-2021, https://doi.org/10.5194/acp-21-12809-2021, 2021
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This study provides a holistic approach to studying the spectrally resolved light absorption by atmospheric brown carbon (BrC) and black carbon using long time series of daily samples from filter-based measurements. The obtained results provide (1) a better understanding of the aerosol absorption profile and its dependence on BrC and on lensing from less absorbing coatings and (2) an estimation of the most important absorbers at typical European locations.
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.
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.
Rosaria E. Pileci, Robin L. Modini, Michele Bertò, Jinfeng Yuan, Joel C. Corbin, Angela Marinoni, Bas Henzing, Marcel M. Moerman, Jean P. Putaud, Gerald Spindler, Birgit Wehner, Thomas Müller, Thomas Tuch, Arianna Trentini, Marco Zanatta, Urs Baltensperger, and Martin Gysel-Beer
Atmos. Meas. Tech., 14, 1379–1403, https://doi.org/10.5194/amt-14-1379-2021, https://doi.org/10.5194/amt-14-1379-2021, 2021
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Black carbon (BC), which is an important constituent of atmospheric aerosols, remains difficult to quantify due to various limitations of available methods. This study provides an extensive comparison of co-located field measurements, applying two methods based on different principles. It was shown that both methods indeed quantify the same aerosol property – BC mass concentration. The level of agreement that can be expected was quantified, and some reasons for discrepancy were identified.
Nikolaos Evangeliou, Stephen M. Platt, Sabine Eckhardt, Cathrine Lund Myhre, Paolo Laj, Lucas Alados-Arboledas, John Backman, Benjamin T. Brem, Markus Fiebig, Harald Flentje, Angela Marinoni, Marco Pandolfi, Jesus Yus-Dìez, Natalia Prats, Jean P. Putaud, Karine Sellegri, Mar Sorribas, Konstantinos Eleftheriadis, Stergios Vratolis, Alfred Wiedensohler, and Andreas Stohl
Atmos. Chem. Phys., 21, 2675–2692, https://doi.org/10.5194/acp-21-2675-2021, https://doi.org/10.5194/acp-21-2675-2021, 2021
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Following the transmission of SARS-CoV-2 to Europe, social distancing rules were introduced to prevent further spread. We investigate the impacts of the European lockdowns on black carbon (BC) emissions by means of in situ observations and inverse modelling. BC emissions declined by 23 kt in Europe during the lockdowns as compared with previous years and by 11 % as compared to the period prior to lockdowns. Residential combustion prevailed in Eastern Europe, as confirmed by remote sensing data.
Rob L. Modini, Joel C. Corbin, Benjamin T. Brem, Martin Irwin, Michele Bertò, Rosaria E. Pileci, Prodromos Fetfatzis, Kostas Eleftheriadis, Bas Henzing, Marcel M. Moerman, Fengshan Liu, Thomas Müller, and Martin Gysel-Beer
Atmos. Meas. Tech., 14, 819–851, https://doi.org/10.5194/amt-14-819-2021, https://doi.org/10.5194/amt-14-819-2021, 2021
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Extinction-minus-scattering is an important method for measuring aerosol light absorption, but its application in the field presents a number of challenges. A recently developed instrument based on this method – the CAPS PMssa – has the potential to overcome some of these challenges. We present a compilation of theory, lab measurements, and field examples to characterize this instrument and show the conditions under which it can deliver reliable absorption measurements for atmospheric aerosols.
Jinfeng Yuan, Robin Lewis Modini, Marco Zanatta, Andreas B. Herber, Thomas Müller, Birgit Wehner, Laurent Poulain, Thomas Tuch, Urs Baltensperger, and Martin Gysel-Beer
Atmos. Chem. Phys., 21, 635–655, https://doi.org/10.5194/acp-21-635-2021, https://doi.org/10.5194/acp-21-635-2021, 2021
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Black carbon (BC) aerosols contribute substantially to climate warming due to their unique light absorption capabilities. We performed field measurements at a central European background site in winter and found that variability in the absorption efficiency of BC particles is driven mainly by their internal mixing state. Our results suggest that, at this site, knowing the BC mixing state is sufficient to describe BC light absorption enhancements due to the lensing effect in good approximation.
Dimitri Osmont, Sandra Brugger, Anina Gilgen, Helga Weber, Michael Sigl, Robin L. Modini, Christoph Schwörer, Willy Tinner, Stefan Wunderle, and Margit Schwikowski
The Cryosphere, 14, 3731–3745, https://doi.org/10.5194/tc-14-3731-2020, https://doi.org/10.5194/tc-14-3731-2020, 2020
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In this interdisciplinary case study, we were able to link biomass burning emissions from the June 2017 wildfires in Portugal to their deposition in the snowpack at Jungfraujoch, Swiss Alps. We analysed black carbon and charcoal in the snowpack, calculated backward trajectories, and monitored the fire evolution by remote sensing. Such case studies help to understand the representativity of biomass burning records in ice cores and how biomass burning tracers are archived in the snowpack.
Leighton A. Regayre, Julia Schmale, Jill S. Johnson, Christian Tatzelt, Andrea Baccarini, Silvia Henning, Masaru Yoshioka, Frank Stratmann, Martin Gysel-Beer, Daniel P. Grosvenor, and Ken S. Carslaw
Atmos. Chem. Phys., 20, 10063–10072, https://doi.org/10.5194/acp-20-10063-2020, https://doi.org/10.5194/acp-20-10063-2020, 2020
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The amount of energy reflected back into space because of man-made particles is highly uncertain. Processes related to naturally occurring particles cause most of the uncertainty, but these processes are poorly constrained by present-day measurements. We show that measurements over the Southern Ocean, far from pollution sources, efficiently reduce climate model uncertainties. Our results pave the way to designing experiments and measurement campaigns that reduce this uncertainty even further.
Paolo Laj, Alessandro Bigi, Clémence Rose, Elisabeth Andrews, Cathrine Lund Myhre, Martine Collaud Coen, Yong Lin, Alfred Wiedensohler, Michael Schulz, John A. Ogren, Markus Fiebig, Jonas Gliß, Augustin Mortier, Marco Pandolfi, Tuukka Petäja, Sang-Woo Kim, Wenche Aas, Jean-Philippe Putaud, Olga Mayol-Bracero, Melita Keywood, Lorenzo Labrador, Pasi Aalto, Erik Ahlberg, Lucas Alados Arboledas, Andrés Alastuey, Marcos Andrade, Begoña Artíñano, Stina Ausmeel, Todor Arsov, Eija Asmi, John Backman, Urs Baltensperger, Susanne Bastian, Olaf Bath, Johan Paul Beukes, Benjamin T. Brem, Nicolas Bukowiecki, Sébastien Conil, Cedric Couret, Derek Day, Wan Dayantolis, Anna Degorska, Konstantinos Eleftheriadis, Prodromos Fetfatzis, Olivier Favez, Harald Flentje, Maria I. Gini, Asta Gregorič, Martin Gysel-Beer, A. Gannet Hallar, Jenny Hand, Andras Hoffer, Christoph Hueglin, Rakesh K. Hooda, Antti Hyvärinen, Ivo Kalapov, Nikos Kalivitis, Anne Kasper-Giebl, Jeong Eun Kim, Giorgos Kouvarakis, Irena Kranjc, Radovan Krejci, Markku Kulmala, Casper Labuschagne, Hae-Jung Lee, Heikki Lihavainen, Neng-Huei Lin, Gunter Löschau, Krista Luoma, Angela Marinoni, Sebastiao Martins Dos Santos, Frank Meinhardt, Maik Merkel, Jean-Marc Metzger, Nikolaos Mihalopoulos, Nhat Anh Nguyen, Jakub Ondracek, Noemi Pérez, Maria Rita Perrone, Jean-Eudes Petit, David Picard, Jean-Marc Pichon, Veronique Pont, Natalia Prats, Anthony Prenni, Fabienne Reisen, Salvatore Romano, Karine Sellegri, Sangeeta Sharma, Gerhard Schauer, Patrick Sheridan, James Patrick Sherman, Maik Schütze, Andreas Schwerin, Ralf Sohmer, Mar Sorribas, Martin Steinbacher, Junying Sun, Gloria Titos, Barbara Toczko, Thomas Tuch, Pierre Tulet, Peter Tunved, Ville Vakkari, Fernando Velarde, Patricio Velasquez, Paolo Villani, Sterios Vratolis, Sheng-Hsiang Wang, Kay Weinhold, Rolf Weller, Margarita Yela, Jesus Yus-Diez, Vladimir Zdimal, Paul Zieger, and Nadezda Zikova
Atmos. Meas. Tech., 13, 4353–4392, https://doi.org/10.5194/amt-13-4353-2020, https://doi.org/10.5194/amt-13-4353-2020, 2020
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The paper establishes the fiducial reference of the GAW aerosol network providing the fully characterized value chain to the provision of four climate-relevant aerosol properties from ground-based sites. Data from almost 90 stations worldwide are reported for a reference year, 2017, providing a unique and very robust view of the variability of these variables worldwide. Current gaps in the GAW network are analysed and requirements for the Global Climate Monitoring System are proposed.
Martine Collaud Coen, Elisabeth Andrews, Andrés Alastuey, Todor Petkov Arsov, John Backman, Benjamin T. Brem, Nicolas Bukowiecki, Cédric Couret, Konstantinos Eleftheriadis, Harald Flentje, Markus Fiebig, Martin Gysel-Beer, Jenny L. Hand, András Hoffer, Rakesh Hooda, Christoph Hueglin, Warren Joubert, Melita Keywood, Jeong Eun Kim, Sang-Woo Kim, Casper Labuschagne, Neng-Huei Lin, Yong Lin, Cathrine Lund Myhre, Krista Luoma, Hassan Lyamani, Angela Marinoni, Olga L. Mayol-Bracero, Nikos Mihalopoulos, Marco Pandolfi, Natalia Prats, Anthony J. Prenni, Jean-Philippe Putaud, Ludwig Ries, Fabienne Reisen, Karine Sellegri, Sangeeta Sharma, Patrick Sheridan, James Patrick Sherman, Junying Sun, Gloria Titos, Elvis Torres, Thomas Tuch, Rolf Weller, Alfred Wiedensohler, Paul Zieger, and Paolo Laj
Atmos. Chem. Phys., 20, 8867–8908, https://doi.org/10.5194/acp-20-8867-2020, https://doi.org/10.5194/acp-20-8867-2020, 2020
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Long-term trends of aerosol radiative properties (52 stations) prove that aerosol load has significantly decreased over the last 20 years. Scattering trends are negative in Europe (EU) and North America (NA), not ss in Asia, and show a mix of positive and negative trends at polar stations. Absorption has mainly negative trends. The single scattering albedo has positive trends in Asia and eastern EU and negative in western EU and NA, leading to a global positive median trend of 0.02 % per year.
Luke T. Cravigan, Marc D. Mallet, Petri Vaattovaara, Mike J. Harvey, Cliff S. Law, Robin L. Modini, Lynn M. Russell, Ed Stelcer, David D. Cohen, Greg Olsen, Karl Safi, Timothy J. Burrell, and Zoran Ristovski
Atmos. Chem. Phys., 20, 7955–7977, https://doi.org/10.5194/acp-20-7955-2020, https://doi.org/10.5194/acp-20-7955-2020, 2020
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Aerosol–cloud interactions in remote marine environments are poorly represented in atmospheric modelling, particularly over the Southern Hemisphere. This work reports in situ chamber observations of sea spray aerosol composition and water uptake during the Surface Ocean Aerosol Production (SOAP) voyage. Observations were compared with currently applied models for sea spray organic enrichment. The sea spray hygroscopicity was persistently high, even at high organic fractions.
Sebastian Landwehr, Iris Thurnherr, Nicolas Cassar, Martin Gysel-Beer, and Julia Schmale
Atmos. Meas. Tech., 13, 3487–3506, https://doi.org/10.5194/amt-13-3487-2020, https://doi.org/10.5194/amt-13-3487-2020, 2020
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Shipborne wind speed measurements are relevant for field studies of air–sea interaction processes. Distortion of the airflow by the ship’s structure can, however, lead to errors. We estimate the flow distortion bias by comparing the observations to ERA-5 reanalysis data. The underlying assumptions are that the bias depends only on the relative orientation of the ship to the wind direction and that the ERA-5 wind speeds are (on average) representative of the true wind speed.
Joel C. Corbin and Martin Gysel-Beer
Atmos. Chem. Phys., 19, 15673–15690, https://doi.org/10.5194/acp-19-15673-2019, https://doi.org/10.5194/acp-19-15673-2019, 2019
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We review the literature to refine the definition of "tar balls" (or tar particles). Then, using a marine-engine data set, we show that a standard SP2 can identify tar particles in two ways, as evaporating and non-incandescing (30 % of tar particles by number) or incandescing particles which scatter more light than soot at incandescence (70 % of tar particles by number). To our knowledge, no other technique can provide in situ, real-time evidence for the presence of tar particles in an aerosol.
George S. Fanourgakis, Maria Kanakidou, Athanasios Nenes, Susanne E. Bauer, Tommi Bergman, Ken S. Carslaw, Alf Grini, Douglas S. Hamilton, Jill S. Johnson, Vlassis A. Karydis, Alf Kirkevåg, John K. Kodros, Ulrike Lohmann, Gan Luo, Risto Makkonen, Hitoshi Matsui, David Neubauer, Jeffrey R. Pierce, Julia Schmale, Philip Stier, Kostas Tsigaridis, Twan van Noije, Hailong Wang, Duncan Watson-Parris, Daniel M. Westervelt, Yang Yang, Masaru Yoshioka, Nikos Daskalakis, Stefano Decesari, Martin Gysel-Beer, Nikos Kalivitis, Xiaohong Liu, Natalie M. Mahowald, Stelios Myriokefalitakis, Roland Schrödner, Maria Sfakianaki, Alexandra P. Tsimpidi, Mingxuan Wu, and Fangqun Yu
Atmos. Chem. Phys., 19, 8591–8617, https://doi.org/10.5194/acp-19-8591-2019, https://doi.org/10.5194/acp-19-8591-2019, 2019
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Effects of aerosols on clouds are important for climate studies but are among the largest uncertainties in climate projections. This study evaluates the skill of global models to simulate aerosol, cloud condensation nuclei (CCN) and cloud droplet number concentrations (CDNCs). Model results show reduced spread in CDNC compared to CCN due to the negative correlation between the sensitivities of CDNC to aerosol number concentration (air pollution) and updraft velocity (atmospheric dynamics).
Ghislain Motos, Julia Schmale, Joel C. Corbin, Rob. L. Modini, Nadine Karlen, Michele Bertò, Urs Baltensperger, and Martin Gysel-Beer
Atmos. Chem. Phys., 19, 3833–3855, https://doi.org/10.5194/acp-19-3833-2019, https://doi.org/10.5194/acp-19-3833-2019, 2019
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Atmospheric black carbon (BC) particles are strong light absorbers that contribute to global warming. In situ cloud measurements performed at a high-altitude site showed that cloud supersaturation mainly drives the activation of BC to cloud droplets. It was further shown how BC particle size and mixing state modulate this nucleation scavenging in agreement with simplified theoretical predictions. These findings can inform model simulations towards a better representation of the BC life cycle.
Ghislain Motos, Julia Schmale, Joel C. Corbin, Marco Zanatta, Urs Baltensperger, and Martin Gysel-Beer
Atmos. Chem. Phys., 19, 2183–2207, https://doi.org/10.5194/acp-19-2183-2019, https://doi.org/10.5194/acp-19-2183-2019, 2019
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Clouds form by condensation of water vapour on aerosol particles. We showed that black carbon, a subset of particles responsible for a climate warming due to their strong light absorption and known to be insoluble in water, were able to form droplets when the humidity of the air is very slightly over 100 %. This is made possible by their acquisition of a
coatingmade of hydrophilic material during atmospheric aging. The predictability of this process using theory was successfully tested.
Nivedita K. Kumar, Joel C. Corbin, Emily A. Bruns, Dario Massabó, Jay G. Slowik, Luka Drinovec, Griša Močnik, Paolo Prati, Athanasia Vlachou, Urs Baltensperger, Martin Gysel, Imad El-Haddad, and André S. H. Prévôt
Atmos. Chem. Phys., 18, 17843–17861, https://doi.org/10.5194/acp-18-17843-2018, https://doi.org/10.5194/acp-18-17843-2018, 2018
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It is clear that considerable uncertainties still exist in understanding the magnitude of aerosol absorption on a global scale and its contribution to global warming. This manuscript provides a comprehensive assessment of the optical absorption by organic aerosols (brown carbon) from residential wood combustion as a function of atmospheric aging.
Marco Zanatta, Paolo Laj, Martin Gysel, Urs Baltensperger, Stergios Vratolis, Konstantinos Eleftheriadis, Yutaka Kondo, Philippe Dubuisson, Victor Winiarek, Stelios Kazadzis, Peter Tunved, and Hans-Werner Jacobi
Atmos. Chem. Phys., 18, 14037–14057, https://doi.org/10.5194/acp-18-14037-2018, https://doi.org/10.5194/acp-18-14037-2018, 2018
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The research community aims to quantify the actual contribution of soot particles to the recent Arctic warming. We discovered that mixing of soot with other components might enhance its light absorption power by 50 %. The neglection of such amplification might lead to the underestimation of radiative forcing by 0.12 W m−2. Thus a better understanding of the optical properties of soot is a crucial step for an accurate quantification of the radiative impact of soot in the Arctic atmosphere.
Marco Pandolfi, Lucas Alados-Arboledas, Andrés Alastuey, Marcos Andrade, Christo Angelov, Begoña Artiñano, John Backman, Urs Baltensperger, Paolo Bonasoni, Nicolas Bukowiecki, Martine Collaud Coen, Sébastien Conil, Esther Coz, Vincent Crenn, Vadimas Dudoitis, Marina Ealo, Kostas Eleftheriadis, Olivier Favez, Prodromos Fetfatzis, Markus Fiebig, Harald Flentje, Patrick Ginot, Martin Gysel, Bas Henzing, Andras Hoffer, Adela Holubova Smejkalova, Ivo Kalapov, Nikos Kalivitis, Giorgos Kouvarakis, Adam Kristensson, Markku Kulmala, Heikki Lihavainen, Chris Lunder, Krista Luoma, Hassan Lyamani, Angela Marinoni, Nikos Mihalopoulos, Marcel Moerman, José Nicolas, Colin O'Dowd, Tuukka Petäjä, Jean-Eudes Petit, Jean Marc Pichon, Nina Prokopciuk, Jean-Philippe Putaud, Sergio Rodríguez, Jean Sciare, Karine Sellegri, Erik Swietlicki, Gloria Titos, Thomas Tuch, Peter Tunved, Vidmantas Ulevicius, Aditya Vaishya, Milan Vana, Aki Virkkula, Stergios Vratolis, Ernest Weingartner, Alfred Wiedensohler, and Paolo Laj
Atmos. Chem. Phys., 18, 7877–7911, https://doi.org/10.5194/acp-18-7877-2018, https://doi.org/10.5194/acp-18-7877-2018, 2018
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This investigation presents the variability in near-surface in situ aerosol particle light-scattering measurements obtained over the past decade at 28 measuring atmospheric observatories which are part of the ACTRIS Research Infrastructure, and most of them belong to the GAW network. This paper provides a comprehensive picture of the spatial and temporal variability of aerosol particles optical properties in Europe.
Julia Schmale, Silvia Henning, Stefano Decesari, Bas Henzing, Helmi Keskinen, Karine Sellegri, Jurgita Ovadnevaite, Mira L. Pöhlker, Joel Brito, Aikaterini Bougiatioti, Adam Kristensson, Nikos Kalivitis, Iasonas Stavroulas, Samara Carbone, Anne Jefferson, Minsu Park, Patrick Schlag, Yoko Iwamoto, Pasi Aalto, Mikko Äijälä, Nicolas Bukowiecki, Mikael Ehn, Göran Frank, Roman Fröhlich, Arnoud Frumau, Erik Herrmann, Hartmut Herrmann, Rupert Holzinger, Gerard Kos, Markku Kulmala, Nikolaos Mihalopoulos, Athanasios Nenes, Colin O'Dowd, Tuukka Petäjä, David Picard, Christopher Pöhlker, Ulrich Pöschl, Laurent Poulain, André Stephan Henry Prévôt, Erik Swietlicki, Meinrat O. Andreae, Paulo Artaxo, Alfred Wiedensohler, John Ogren, Atsushi Matsuki, Seong Soo Yum, Frank Stratmann, Urs Baltensperger, and Martin Gysel
Atmos. Chem. Phys., 18, 2853–2881, https://doi.org/10.5194/acp-18-2853-2018, https://doi.org/10.5194/acp-18-2853-2018, 2018
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Collocated long-term observations of cloud condensation nuclei (CCN) number concentrations, particle number size distributions and chemical composition from 12 sites are synthesized. Observations cover coastal environments, the Arctic, the Mediterranean, the boreal and rain forest, high alpine and continental background sites, and Monsoon-influenced areas. We interpret regional and seasonal variability. CCN concentrations are predicted with the κ–Köhler model and compared to the measurements.
Peter Zotter, Hanna Herich, Martin Gysel, Imad El-Haddad, Yanlin Zhang, Griša Močnik, Christoph Hüglin, Urs Baltensperger, Sönke Szidat, and André S. H. Prévôt
Atmos. Chem. Phys., 17, 4229–4249, https://doi.org/10.5194/acp-17-4229-2017, https://doi.org/10.5194/acp-17-4229-2017, 2017
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Most studies use a single Ångström exponent for wood burning (αWB) and traffic (αTR) emissions in the Aethalometer model, used for source apportionment of black carbon, derived from previous work. However, accurate determination of the α values is currently lacking. Comparing radiocarbon measurements (14C) with the Aehtalometer model, good agreement was found, indicating that the Aethalometer model reproduces reasonably well the 14C results using our best estimate of a single αWB and αTR.
Rob L. Modini and Satoshi Takahama
Atmos. Meas. Tech., 9, 3337–3354, https://doi.org/10.5194/amt-9-3337-2016, https://doi.org/10.5194/amt-9-3337-2016, 2016
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Aerosol measurement techniques with high detection limits often result in poorly time-resolved measurements. We investigated sampling strategies and post-processing methods for constructing hourly resolved aerosol concentration time series from samples collected for 4 to 8 h. We show that this is an effective way to increase measurement time resolution, and that under realistic experimental conditions, simple methods can perform as well as more sophisticated methods.
Bernadette Rosati, Martin Gysel, Florian Rubach, Thomas F. Mentel, Brigitta Goger, Laurent Poulain, Patrick Schlag, Pasi Miettinen, Aki Pajunoja, Annele Virtanen, Henk Klein Baltink, J. S. Bas Henzing, Johannes Größ, Gian Paolo Gobbi, Alfred Wiedensohler, Astrid Kiendler-Scharr, Stefano Decesari, Maria Cristina Facchini, Ernest Weingartner, and Urs Baltensperger
Atmos. Chem. Phys., 16, 7295–7315, https://doi.org/10.5194/acp-16-7295-2016, https://doi.org/10.5194/acp-16-7295-2016, 2016
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This study presents PEGASOS project data from field campaigns in the Po Valley, Italy and the Netherlands. Vertical profiles of aerosol hygroscopicity and chemical composition were investigated with airborne measurements on board a Zeppelin NT airship. A special focus was on the evolution of different mixing layers within the PBL as a function of daytime. A closure study showed that variations in aerosol hygroscopicity can well be explained by the variations in chemical composition.
Bernadette Rosati, Erik Herrmann, Silvia Bucci, Federico Fierli, Francesco Cairo, Martin Gysel, Ralf Tillmann, Johannes Größ, Gian Paolo Gobbi, Luca Di Liberto, Guido Di Donfrancesco, Alfred Wiedensohler, Ernest Weingartner, Annele Virtanen, Thomas F. Mentel, and Urs Baltensperger
Atmos. Chem. Phys., 16, 4539–4554, https://doi.org/10.5194/acp-16-4539-2016, https://doi.org/10.5194/acp-16-4539-2016, 2016
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We present vertical profiles of aerosol optical properties, which were explored within the planetary boundary layer in a case study in 2012 in the Po Valley region. A comparison of in situ measurements recorded aboard a Zeppelin NT and ground-based remote-sensing data was performed yielding good agreement. Additionally, the role of ambient relative humidity for the aerosol particles' optical properties was investigated.
Christopher R. Hoyle, Clare S. Webster, Harald E. Rieder, Athanasios Nenes, Emanuel Hammer, Erik Herrmann, Martin Gysel, Nicolas Bukowiecki, Ernest Weingartner, Martin Steinbacher, and Urs Baltensperger
Atmos. Chem. Phys., 16, 4043–4061, https://doi.org/10.5194/acp-16-4043-2016, https://doi.org/10.5194/acp-16-4043-2016, 2016
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A simple statistical model to predict the number of aerosols which activate to form cloud droplets in warm clouds has been established, based on regression analysis of data from the high-altitude site Jungfraujoch. It is found that cloud droplet formation at the Jungfraujoch is predominantly controlled by the number concentration of aerosol particles. A statistical model based on only the number of particles larger than 80nm can explain 79 % of the observed variance in droplet numbers.
C. R. Hoyle, C. Fuchs, E. Järvinen, H. Saathoff, A. Dias, I. El Haddad, M. Gysel, S. C. Coburn, J. Tröstl, A.-K. Bernhammer, F. Bianchi, M. Breitenlechner, J. C. Corbin, J. Craven, N. M. Donahue, J. Duplissy, S. Ehrhart, C. Frege, H. Gordon, N. Höppel, M. Heinritzi, T. B. Kristensen, U. Molteni, L. Nichman, T. Pinterich, A. S. H. Prévôt, M. Simon, J. G. Slowik, G. Steiner, A. Tomé, A. L. Vogel, R. Volkamer, A. C. Wagner, R. Wagner, A. S. Wexler, C. Williamson, P. M. Winkler, C. Yan, A. Amorim, J. Dommen, J. Curtius, M. W. Gallagher, R. C. Flagan, A. Hansel, J. Kirkby, M. Kulmala, O. Möhler, F. Stratmann, D. R. Worsnop, and U. Baltensperger
Atmos. Chem. Phys., 16, 1693–1712, https://doi.org/10.5194/acp-16-1693-2016, https://doi.org/10.5194/acp-16-1693-2016, 2016
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A significant portion of sulphate, an important constituent of atmospheric aerosols, is formed via the aqueous phase oxidation of sulphur dioxide by ozone. The rate of this reaction has previously only been measured over a relatively small temperature range. Here, we use the state of the art CLOUD chamber at CERN to perform the first measurements of this reaction rate in super-cooled droplets, confirming that the existing extrapolation of the reaction rate to sub-zero temperatures is accurate.
M. Paramonov, V.-M. Kerminen, M. Gysel, P. P. Aalto, M. O. Andreae, E. Asmi, U. Baltensperger, A. Bougiatioti, D. Brus, G. P. Frank, N. Good, S. S. Gunthe, L. Hao, M. Irwin, A. Jaatinen, Z. Jurányi, S. M. King, A. Kortelainen, A. Kristensson, H. Lihavainen, M. Kulmala, U. Lohmann, S. T. Martin, G. McFiggans, N. Mihalopoulos, A. Nenes, C. D. O'Dowd, J. Ovadnevaite, T. Petäjä, U. Pöschl, G. C. Roberts, D. Rose, B. Svenningsson, E. Swietlicki, E. Weingartner, J. Whitehead, A. Wiedensohler, C. Wittbom, and B. Sierau
Atmos. Chem. Phys., 15, 12211–12229, https://doi.org/10.5194/acp-15-12211-2015, https://doi.org/10.5194/acp-15-12211-2015, 2015
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The research paper presents the first comprehensive overview of field measurements with the CCN Counter performed at a large number of locations around the world within the EUCAARI framework. The paper sheds light on the CCN number concentrations and activated fractions around the world and their dependence on the water vapour supersaturation ratio, the dependence of aerosol hygroscopicity on particle size, and seasonal and diurnal variation of CCN activation and hygroscopic properties.
R. Fröhlich, M. J. Cubison, J. G. Slowik, N. Bukowiecki, F. Canonaco, P. L. Croteau, M. Gysel, S. Henne, E. Herrmann, J. T. Jayne, M. Steinbacher, D. R. Worsnop, U. Baltensperger, and A. S. H. Prévôt
Atmos. Chem. Phys., 15, 11373–11398, https://doi.org/10.5194/acp-15-11373-2015, https://doi.org/10.5194/acp-15-11373-2015, 2015
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This manuscript presents the first long-term (14-month) and highly time-resolved (10 min) measurements of NR-PM1 aerosol chemical composition at a high-altitude site (JFJ, Switzerland, 3580m a.s.l.). The elevated location allowed the investigation of free tropospheric aerosol year round. Total and relative mass loadings, diurnal variations as well as seasonal variations are discussed together with geographical origin, organic aerosol sources and the influence of the planetary boundary layer.
H. M. Allen, D. C. Draper, B. R. Ayres, A. Ault, A. Bondy, S. Takahama, R. L. Modini, K. Baumann, E. Edgerton, C. Knote, A. Laskin, B. Wang, and J. L. Fry
Atmos. Chem. Phys., 15, 10669–10685, https://doi.org/10.5194/acp-15-10669-2015, https://doi.org/10.5194/acp-15-10669-2015, 2015
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We report ion chromatographic measurements of gas- and aerosol-phase inorganic species at the SOAS 2013 field study. Our particular focus is on inorganic nitrate aerosol formation via HNO3 uptake onto coarse-mode dust and sea salt particles, which we find to be the dominant source of episodic inorganic nitrate at this site, due to the high acidity of the particles preventing formation of NH4NO3. We calculate a production rate of inorganic nitrate aerosol.
P. Kupiszewski, E. Weingartner, P. Vochezer, M. Schnaiter, A. Bigi, M. Gysel, B. Rosati, E. Toprak, S. Mertes, and U. Baltensperger
Atmos. Meas. Tech., 8, 3087–3106, https://doi.org/10.5194/amt-8-3087-2015, https://doi.org/10.5194/amt-8-3087-2015, 2015
B. Rosati, G. Wehrle, M. Gysel, P. Zieger, U. Baltensperger, and E. Weingartner
Atmos. Meas. Tech., 8, 921–939, https://doi.org/10.5194/amt-8-921-2015, https://doi.org/10.5194/amt-8-921-2015, 2015
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Only few measurements focused on vertical profiles of aerosol hygroscopic and optical properties in airborne studies. For this purpose the white-light optical particle spectrometer (WHOPS) was developed. It allows a relatively fast measurement of the particles hygroscopicity, mixing state and index of refraction of particles in the optically relevant size range. This paper presents a detailed technical description and characterization of the WHOPS and first results from the field.
J. C. Schroder, S. J. Hanna, R. L. Modini, A. L. Corrigan, S. M. Kreidenwies, A. M. Macdonald, K. J. Noone, L. M. Russell, W. R. Leaitch, and A. K. Bertram
Atmos. Chem. Phys., 15, 1367–1383, https://doi.org/10.5194/acp-15-1367-2015, https://doi.org/10.5194/acp-15-1367-2015, 2015
D. B. Collins, D. F. Zhao, M. J. Ruppel, O. Laskina, J. R. Grandquist, R. L. Modini, M. D. Stokes, L. M. Russell, T. H. Bertram, V. H. Grassian, G. B. Deane, and K. A. Prather
Atmos. Meas. Tech., 7, 3667–3683, https://doi.org/10.5194/amt-7-3667-2014, https://doi.org/10.5194/amt-7-3667-2014, 2014
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Sea spray aerosol particles represent a system of relatively high chemical complexity. The chemical composition of sea spray aerosol particles was shown in this study to be directly determined by the method used to produce bubbles, which produce aerosol upon bursting at the sea surface. Using methods which deviate from natural breaking waves directly translated into differences in the measured particle sizes and the chemical mixing state of laboratory-generated sea spray aerosol particles.
E. Hammer, M. Gysel, G. C. Roberts, T. Elias, J. Hofer, C. R. Hoyle, N. Bukowiecki, J.-C. Dupont, F. Burnet, U. Baltensperger, and E. Weingartner
Atmos. Chem. Phys., 14, 10517–10533, https://doi.org/10.5194/acp-14-10517-2014, https://doi.org/10.5194/acp-14-10517-2014, 2014
I. A. Wendl, J. A. Menking, R. Färber, M. Gysel, S. D. Kaspari, M. J. G. Laborde, and M. Schwikowski
Atmos. Meas. Tech., 7, 2667–2681, https://doi.org/10.5194/amt-7-2667-2014, https://doi.org/10.5194/amt-7-2667-2014, 2014
S. Kaspari, T. H. Painter, M. Gysel, S. M. Skiles, and M. Schwikowski
Atmos. Chem. Phys., 14, 8089–8103, https://doi.org/10.5194/acp-14-8089-2014, https://doi.org/10.5194/acp-14-8089-2014, 2014
F. Dahlkötter, M. Gysel, D. Sauer, A. Minikin, R. Baumann, P. Seifert, A. Ansmann, M. Fromm, C. Voigt, and B. Weinzierl
Atmos. Chem. Phys., 14, 6111–6137, https://doi.org/10.5194/acp-14-6111-2014, https://doi.org/10.5194/acp-14-6111-2014, 2014
J. C. Corbin, B. Sierau, M. Gysel, M. Laborde, A. Keller, J. Kim, A. Petzold, T. B. Onasch, U. Lohmann, and A. A. Mensah
Atmos. Chem. Phys., 14, 2591–2603, https://doi.org/10.5194/acp-14-2591-2014, https://doi.org/10.5194/acp-14-2591-2014, 2014
E. Hammer, N. Bukowiecki, M. Gysel, Z. Jurányi, C. R. Hoyle, R. Vogt, U. Baltensperger, and E. Weingartner
Atmos. Chem. Phys., 14, 1123–1139, https://doi.org/10.5194/acp-14-1123-2014, https://doi.org/10.5194/acp-14-1123-2014, 2014
D. Rose, S. S. Gunthe, Z. Jurányi, M. Gysel, G. P. Frank, J. Schneider, J. Curtius, and U. Pöschl
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acpd-13-32575-2013, https://doi.org/10.5194/acpd-13-32575-2013, 2013
Revised manuscript has not been submitted
A. Wonaschütz, M. Coggon, A. Sorooshian, R. Modini, A. A. Frossard, L. Ahlm, J. Mülmenstädt, G. C. Roberts, L. M. Russell, S. Dey, F. J. Brechtel, and J. H. Seinfeld
Atmos. Chem. Phys., 13, 9819–9835, https://doi.org/10.5194/acp-13-9819-2013, https://doi.org/10.5194/acp-13-9819-2013, 2013
Z. Jurányi, T. Tritscher, M. Gysel, M. Laborde, L. Gomes, G. Roberts, U. Baltensperger, and E. Weingartner
Atmos. Chem. Phys., 13, 6431–6446, https://doi.org/10.5194/acp-13-6431-2013, https://doi.org/10.5194/acp-13-6431-2013, 2013
M. Laborde, M. Crippa, T. Tritscher, Z. Jurányi, P. F. Decarlo, B. Temime-Roussel, N. Marchand, S. Eckhardt, A. Stohl, U. Baltensperger, A. S. H. Prévôt, E. Weingartner, and M. Gysel
Atmos. Chem. Phys., 13, 5831–5856, https://doi.org/10.5194/acp-13-5831-2013, https://doi.org/10.5194/acp-13-5831-2013, 2013
H. Keskinen, A. Virtanen, J. Joutsensaari, G. Tsagkogeorgas, J. Duplissy, S. Schobesberger, M. Gysel, F. Riccobono, J. G. Slowik, F. Bianchi, T. Yli-Juuti, K. Lehtipalo, L. Rondo, M. Breitenlechner, A. Kupc, J. Almeida, A. Amorim, E. M. Dunne, A. J. Downard, S. Ehrhart, A. Franchin, M.K. Kajos, J. Kirkby, A. Kürten, T. Nieminen, V. Makhmutov, S. Mathot, P. Miettinen, A. Onnela, T. Petäjä, A. Praplan, F. D. Santos, S. Schallhart, M. Sipilä, Y. Stozhkov, A. Tomé, P. Vaattovaara, D. Wimmer, A. Prevot, J. Dommen, N. M. Donahue, R.C. Flagan, E. Weingartner, Y. Viisanen, I. Riipinen, A. Hansel, J. Curtius, M. Kulmala, D. R. Worsnop, U. Baltensperger, H. Wex, F. Stratmann, and A. Laaksonen
Atmos. Chem. Phys., 13, 5587–5600, https://doi.org/10.5194/acp-13-5587-2013, https://doi.org/10.5194/acp-13-5587-2013, 2013
M. Frosch, M. Bilde, A. Nenes, A. P. Praplan, Z. Jurányi, J. Dommen, M. Gysel, E. Weingartner, and U. Baltensperger
Atmos. Chem. Phys., 13, 2283–2297, https://doi.org/10.5194/acp-13-2283-2013, https://doi.org/10.5194/acp-13-2283-2013, 2013
M. Laborde, M. Schnaiter, C. Linke, H. Saathoff, K.-H. Naumann, O. Möhler, S. Berlenz, U. Wagner, J. W. Taylor, D. Liu, M. Flynn, J. D. Allan, H. Coe, K. Heimerl, F. Dahlkötter, B. Weinzierl, A. G. Wollny, M. Zanatta, J. Cozic, P. Laj, R. Hitzenberger, J. P. Schwarz, and M. Gysel
Atmos. Meas. Tech., 5, 3077–3097, https://doi.org/10.5194/amt-5-3077-2012, https://doi.org/10.5194/amt-5-3077-2012, 2012
M. Gysel, M. Laborde, A. A. Mensah, J. C. Corbin, A. Keller, J. Kim, A. Petzold, and B. Sierau
Atmos. Meas. Tech., 5, 3099–3107, https://doi.org/10.5194/amt-5-3099-2012, https://doi.org/10.5194/amt-5-3099-2012, 2012
Related subject area
Subject: Aerosols | Technique: Laboratory Measurement | Topic: Instruments and Platforms
A comprehensive characterization of empirical parameterizations for OH exposure in the Aerodyne Potential Aerosol Mass Oxidation Flow Reactor (PAM-OFR)
The UNAM-MARine Aerosol Tank (UNAM-MARAT): an evaluation of the ice-nucleating abilities of seawater from the Gulf of Mexico and the Mexican Pacific
Characterization of the Newly Designed Wall-Free Particle Evaporator (WALL-E) for Online Measurements of Atmospheric Particles
Determining optimal sampling conditions in the TSI Nanometer Aerosol Sampler 3089
Characterization of filter photometer artefacts in soot and dust measurements – laboratory and ambient experiments using a traceably-calibrated aerosol absorption reference
A novel methodology for assessing the hygroscopicity of aerosol filter samples
Direct calibration using atmospheric particles and performance evaluation of Particle Size Magnifier (PSM) 2.0 for sub-10 nm particle measurements
The Coupling of a High-efficiency Aerosol Collector with Electrospray Ionisation/Orbitrap Mass Spectrometry as a novel tool for Real-time Chemical Characterisation of Fine and Ultrafine Particles
Merging holography, fluorescence, and machine learning for in situ continuous characterization and classification of airborne microplastics
Rapid quantitative analysis of semi-volatile organic compounds in indoor surface film using direct analysis in real time mass spectrometry: a case study on phthalates
Design and performance of the Cluster Ion Counter (CIC)
Design of Wide Particle Size Range Aerodynamic Inlet System with New Pre-focus Structure
Exploring non-soluble particles in hailstones through innovative confocal laser and scanning electron microscopy techniques
A comprehensive evaluation of enhanced temperature influence on gas and aerosol chemistry in the lamp-enclosed oxidation flow reactor (OFR) system
An oxidation flow reactor for simulating and accelerating secondary aerosol formation in aerosol liquid water and cloud droplets
Surface equilibrium vapor pressure of organic nanoparticles measured from the dynamic-aerosol-size electrical mobility spectrometer
Quality assurance and quality control of atmospheric organosulfates measured using hydrophilic interaction liquid chromatography (HILIC)
Micro-PINGUIN: microtiter-plate-based instrument for ice nucleation detection in gallium with an infrared camera
Characterization of the Vaporization Inlet for Aerosols (VIA) for online measurements of particulate highly oxygenated organic molecules (HOMs)
Development and characterization of a high-performance single-particle aerosol mass spectrometer (HP-SPAMS)
Characterization of the planar differential mobility analyzer (DMA P5): resolving power, transmission efficiency and its application to atmospheric relevant cluster measurements
Airborne bacteria viability and air quality: a protocol to quantitatively investigate the possible correlation by an atmospheric simulation chamber
The viscosity and surface tension of supercooled levitated droplets determined by excitation of shape oscillations
Acoustic levitation of pollen and visualisation of hygroscopic behaviour
A new smog chamber system for atmospheric multiphase chemistry study: design and characterization
Stability assessment of organic sulfur and organosulfate compounds in filter samples for quantification by Fourier- transform infrared spectroscopy
Design and evaluation of a thermal precipitation aerosol electrometer (TPAE)
An automated online field instrument to quantify the oxidative potential of aerosol particles via ascorbic acid oxidation
Online measurement of highly oxygenated compounds from organic aerosol
The AERosol and TRACe gas Collector (AERTRACC): an online-measurement-controlled sampler for source-resolved emission analysis
Quantitative chemical assay of nanogram-level particulate matter using aerosol mass spectrometry: characterization of particles collected from uncrewed atmospheric measurement platforms
An optimised organic carbon ∕ elemental carbon (OC ∕ EC) fraction separation method for radiocarbon source apportionment applied to low-loaded Arctic aerosol filters
Investigating the dependence of mineral dust depolarization on complex refractive index and size with a laboratory polarimeter at 180.0° lidar backscattering angle
Evaluation of a low-cost dryer for a low-cost optical particle counter
Effects of temperature and salinity on bubble-bursting aerosol formation simulated with a bubble-generating chamber
A new hot-stage microscopy technique for measuring temperature-dependent viscosities of aerosol particles and its application to farnesene secondary organic aerosol
Characterization of a modified printed optical particle spectrometer for high-frequency and high-precision laboratory and field measurements
Design and fabrication of an electrostatic precipitator for infrared spectroscopy
Combined application of online FIGAERO-CIMS and offline LC-Orbitrap mass spectrometry (MS) to characterize the chemical composition of secondary organic aerosol (SOA) in smog chamber studies
High-frequency gaseous and particulate chemical characterization using extractive electrospray ionization mass spectrometry (Dual-Phase-EESI-TOF)
An evaluation of the heat test for the ice-nucleating ability of minerals and biological material
Development, characterization, and application of an improved online reactive oxygen species analyzer based on the Monitor for AeRosols and Gases in ambient Air (MARGA)
Characterization of soot produced by the mini inverted soot generator with an atmospheric simulation chamber
LED-based solar simulator to study photochemistry over a wide temperature range in the large simulation chamber AIDA
Laboratory evaluation of the scattering matrix of ragweed, ash, birch and pine pollen towards pollen classification
Cloud condensation nuclei (CCN) activity analysis of low-hygroscopicity aerosols using the aerodynamic aerosol classifier (AAC)
Characterisation of the Manchester Aerosol Chamber facility
A study on the fragmentation of sulfuric acid and dimethylamine clusters inside an atmospheric pressure interface time-of-flight mass spectrometer
A semi-automated instrument for cellular oxidative potential evaluation (SCOPE) of water-soluble extracts of ambient particulate matter
Utilizing an electrical low-pressure impactor to indirectly probe water uptake via particle bounce measurements
Qianying Liu, Dan Dan Huang, Andrew T. Lambe, Shengrong Lou, Lulu Zeng, Yuhang Wu, Congyan Huang, Shikang Tao, Xi Cheng, Qi Chen, Ka In Hoi, Hongli Wang, Kai Meng Mok, Cheng Huang, and Yong Jie Li
Atmos. Meas. Tech., 18, 2509–2521, https://doi.org/10.5194/amt-18-2509-2025, https://doi.org/10.5194/amt-18-2509-2025, 2025
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We evaluate the applicability of empirical equations to estimate OH exposure (OHexp) in an oxidative flow reactor (OFR). The fitting parameters obtained within a narrow range of conditions can generally be extended to estimate the OHexp for wide ranges of conditions in the OFR, except for external OH reactivity, which requires new fitting. At least 20–30 data points from SO2 or CO decay with varying conditions are required to fit a set of empirical parameters that can accurately estimate OHexp.
M. Fernanda Córdoba, Rachel Chang, Harry Alvarez-Ospina, Aramis Olivos-Ortiz, Graciela B. Raga, Daniel Rosas-Ramírez, Guadalupe Campos, Isabel Márquez, Telma Castro, and Luis A. Ladino
Atmos. Meas. Tech., 18, 2463–2479, https://doi.org/10.5194/amt-18-2463-2025, https://doi.org/10.5194/amt-18-2463-2025, 2025
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The present study shows the development of the UNAM-MARine Aerosol Tank (UNAM-MARAT), a device that simulates wave breaking to generate marine aerosol particles. The portable and automatic tank is able to generate particle concentrations as high as 2000 cm-3, covering a wide range of sizes, similar to those found in the ambient marine boundary layer. The sea spray aerosol generated from three natural seawater samples was found to act as ice-nucleating particles (INPs) via immersion freezing.
Linyu Gao, Imad Zgheib, Evangelos Stergiou, Cecilie Carstens, Félix Sari Doré, Michel Dupanloup, Frederic Bourgain, Sebastien Perrier, and Matthieu Riva
EGUsphere, https://doi.org/10.5194/egusphere-2025-1072, https://doi.org/10.5194/egusphere-2025-1072, 2025
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In this work, we introduce WALL-E, a newly designed Wall-Free Particle Evaporator that enables real-time, online aerosol analysis while minimizing wall interactions and fragmentation, offering a more accurate and efficient approach to studying aerosol properties. WALL-E provides molecular-level insights into aerosol composition, quantification, and volatility distributions.
Behnaz Alinaghipour, Sadegh Niazi, Robert Groth, Branka Miljevic, and Zoran Ristovski
Atmos. Meas. Tech., 18, 1063–1071, https://doi.org/10.5194/amt-18-1063-2025, https://doi.org/10.5194/amt-18-1063-2025, 2025
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Airborne particles are crucial in environmental and health studies, requiring precise sampling for accurate characterisation. Our study examines the optimal sampling time for the TSI Nanometer Aerosol Sampler 3089 at different input concentrations. Aerosols from low-, medium-, and high-concentration environments were sampled over 1, 3, and 6 h. A linear relationship was observed using a regression model between the deposition densities and the product of input concentration and sampling time.
Jesús Yus-Díez, Luka Drinovec, Lucas Alados-Arboledas, Gloria Titos, Elena Bazo, Andrea Casans, Diego Patrón, Xavier Querol, Adolfo Gonzalez-Romero, Carlos Perez García-Pando, and Griša Močnik
EGUsphere, https://doi.org/10.5194/egusphere-2024-3995, https://doi.org/10.5194/egusphere-2024-3995, 2025
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We have used absorption from a photo-thermal interferometer and scattering measurements, to evaluate the most deployed filter photometers used to measure absorption at monitoring networks. We used soot and dust-dominated aerosol samples in both laboratory and ambient settings. Our results indicated that one of these filter photometers, the MAAP, usually used as a pseudo-reference instrument, had 47 % higher absorption values than our reference measurements.
Nagendra Raparthi, Anthony S. Wexler, and Ann M. Dillner
Atmos. Meas. Tech., 18, 603–618, https://doi.org/10.5194/amt-18-603-2025, https://doi.org/10.5194/amt-18-603-2025, 2025
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Quantifying the composition-dependent hygroscopicity of aerosol particles is essential for advancing our understanding of atmospheric processes. Existing methods do not integrate chemical composition with hygroscopicity. We developed a novel method to assess the water uptake of particles sampled on aerosol filters at relative humidity levels up to 97 % and link it with their composition. This approach allows for the separation of total water uptake into inorganic and organic components.
Yiliang Liu, Arttu Yli-Kujala, Fabian Schmidt-Ott, Sebastian Holm, Lauri Ahonen, Tommy Chan, Joonas Enroth, Joonas Vanhanen, Runlong Cai, Tuukka Petäjä, Markku Kulmala, Yang Chen, and Juha Kangasluoma
Atmos. Meas. Tech., 18, 431–442, https://doi.org/10.5194/amt-18-431-2025, https://doi.org/10.5194/amt-18-431-2025, 2025
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Accurate measurement of nanoparticles is crucial for understanding their impact on new particle formation and climate change. In this study, we calibrated the Particle Size Magnifier version 2.0 (PSM 2.0), using both laboratory-generated and atmospheric particles. Some differences were observed in the calibration results, with direct calibration using atmospheric particles enhancing measurement accuracy.
Yik-Sze Lau, Zoran Ristovski, and Branka Miljevic
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2024-192, https://doi.org/10.5194/amt-2024-192, 2025
Revised manuscript accepted for AMT
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The chemical properties of aerosols in the atmosphere significantly influence their impact on global climate and human health. The current study constructed an instrumental system (HEAC/ESI-Orbitrap-MS) for the real-time chemical analysis of aerosol samples. The combined system successfully identified over three hundred chemical compounds in aerosol samples in real-time, showing the robustness of the technique for the chemical characterisation of aerosols under atmospheric relevant conditions.
Nicholas D. Beres, Julia Burkart, Elias Graf, Yanick Zeder, Lea Ann Dailey, and Bernadett Weinzierl
Atmos. Meas. Tech., 17, 6945–6964, https://doi.org/10.5194/amt-17-6945-2024, https://doi.org/10.5194/amt-17-6945-2024, 2024
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We tested a method to identify airborne microplastics (MPs), merging imaging, fluorescence, and machine learning of single particles. We examined whether combining imaging and fluorescence data enhances classification accuracy compared to using each method separately and tested these methods with other particle types. The tested MPs have distinct fluorescence, and a combined imaging and fluorescence method improves their detection, making meaningful progress in monitoring MPs in the atmosphere.
Ying Zhou, Longkun He, Jiang Tan, Jiang Zhou, and Yingjun Liu
Atmos. Meas. Tech., 17, 6415–6423, https://doi.org/10.5194/amt-17-6415-2024, https://doi.org/10.5194/amt-17-6415-2024, 2024
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We present a sensitive DART-MS/MS method for the fast and accurate quantification of semi-volatile organic compounds (SVOCs) in organic films without the need for pre-treatment. This method offers greatly improved repeatability in the absence of internal standards. By utilizing MS/MS analysis, the separation of isomeric components within films becomes possible. These developments increase the feasibility of the DART-MS approach for studying the dynamics of SVOCs in indoor surface films.
Sander Mirme, Rima Balbaaki, Hanna Elina Manninen, Paap Koemets, Eva Sommer, Birte Rörup, Yusheng Wu, Joao Almeida, Sebastian Ehrhart, Stefan Karl Weber, Joschka Pfeifer, Juha Kangasluoma, Markku Kulmala, and Jasper Kirkby
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2024-138, https://doi.org/10.5194/amt-2024-138, 2024
Revised manuscript accepted for AMT
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The manuscript describes the design and performance of the Cluster Ion Counter (CIC, Airel OÜ), a device which simultaneously measures the number concentrations of positively- and negatively-charged ions and particles below 5 nm mobility diameter. The presented measurements and operational experience demonstrate that the CIC provides precise and robust long-term measurements of small ion concentrations of both polarities, with low noise, fast time response and excellent reliability.
Junhong Huang, Lei Li, Xue Li, Zhengxu Huang, and Zhi Cheng
EGUsphere, https://doi.org/10.5194/egusphere-2024-2577, https://doi.org/10.5194/egusphere-2024-2577, 2024
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We developed an aerodynamic sampling system that extends the PM2.5 lens transmission range to 10 µm. This approach reduces the beam incidence angle and narrows the beam width compared to earlier designs. Using PSL balls, we confirmed the injection system's high transmission performance. Tests with standard dust sample showed consistency with APS results. This study presents a new design framework that enhances transmission range and efficiency while supporting instrument miniaturization.
Anthony C. Bernal Ayala, Angela K. Rowe, Lucia E. Arena, William O. Nachlas, and Maria L. Asar
Atmos. Meas. Tech., 17, 5561–5579, https://doi.org/10.5194/amt-17-5561-2024, https://doi.org/10.5194/amt-17-5561-2024, 2024
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Hail is a challenging weather phenomenon to forecast due to an incomplete understanding of hailstone formation. Microscopy temperature limitations required previous studies to melt hail for analysis. This paper introduces a unique technique using a plastic cover to preserve particles in their location within the hailstone without melting. Therefore, CLSM and SEM–EDS microscopes can be used to determine individual particle sizes and their chemical composition related to hail-formation processes.
Tianle Pan, Andrew T. Lambe, Weiwei Hu, Yicong He, Minghao Hu, Huaishan Zhou, Xinming Wang, Qingqing Hu, Hui Chen, Yue Zhao, Yuanlong Huang, Doug R. Worsnop, Zhe Peng, Melissa A. Morris, Douglas A. Day, Pedro Campuzano-Jost, Jose-Luis Jimenez, and Shantanu H. Jathar
Atmos. Meas. Tech., 17, 4915–4939, https://doi.org/10.5194/amt-17-4915-2024, https://doi.org/10.5194/amt-17-4915-2024, 2024
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This study systematically characterizes the temperature enhancement in the lamp-enclosed oxidation flow reactor (OFR). The enhancement varied multiple dimensional factors, emphasizing the complexity of temperature inside of OFR. The effects of temperature on the flow field and gas- or particle-phase reaction inside OFR were also evaluated with experiments and model simulations. Finally, multiple mitigation strategies were demonstrated to minimize this temperature increase.
Ningjin Xu, Chen Le, David R. Cocker, Kunpeng Chen, Ying-Hsuan Lin, and Don R. Collins
Atmos. Meas. Tech., 17, 4227–4243, https://doi.org/10.5194/amt-17-4227-2024, https://doi.org/10.5194/amt-17-4227-2024, 2024
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A flow-through reactor was developed that exposes known mixtures of gases or ambient air to very high concentrations of the oxidants that are responsible for much of the chemistry that takes place in the atmosphere. Like other reactors of its type, it is primarily used to study the formation of particulate matter from the oxidation of common gases. Unlike other reactors of its type, it can simulate the chemical reactions that occur in liquid water that is present in particles or cloud droplets.
Ella Häkkinen, Huan Yang, Runlong Cai, and Juha Kangasluoma
Atmos. Meas. Tech., 17, 4211–4225, https://doi.org/10.5194/amt-17-4211-2024, https://doi.org/10.5194/amt-17-4211-2024, 2024
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We report measurements of evaporation kinetics and surface equilibrium vapor pressures for various laboratory-generated organic nanoparticles using the dynamic-aerosol-size electrical mobility spectrometer (DEMS), a recent advancement in aerosol process characterization. Our findings align well with literature values, demonstrating DEMS's effectiveness. We suggest future improvements to DEMS and anticipate its potential for probing aerosol-related kinetic processes with unknown mechanisms.
Ping Liu, Xiang Ding, Bo-Xuan Li, Yu-Qing Zhang, Daniel J. Bryant, and Xin-Ming Wang
Atmos. Meas. Tech., 17, 3067–3079, https://doi.org/10.5194/amt-17-3067-2024, https://doi.org/10.5194/amt-17-3067-2024, 2024
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In this paper, we further optimize the measurement of atmospheric organosulfates by hydrophilic interaction liquid chromatography (HILIC), offering an improved method for quantifying and speciating atmospheric organosulfates. These efforts will contribute to a deeper understanding of secondary organic aerosol precursors, formation mechanisms, and the contribution of organosulfate to atmospheric aerosols, ultimately guiding research in the field of air pollution prevention and control.
Corina Wieber, Mads Rosenhøj Jeppesen, Kai Finster, Claus Melvad, and Tina Šantl-Temkiv
Atmos. Meas. Tech., 17, 2707–2719, https://doi.org/10.5194/amt-17-2707-2024, https://doi.org/10.5194/amt-17-2707-2024, 2024
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We developed a novel instrument to determine the quality and number of biological and non-biological particles, with respect to their ice-promoting capacity as a function of temperature. The measurement uncertainty was determined, and the instrument produced reliable results. Further, repeated measurements of the same suspension showed that the instrument had high reproducibility.
Jian Zhao, Valter Mickwitz, Yuanyuan Luo, Ella Häkkinen, Frans Graeffe, Jiangyi Zhang, Hilkka Timonen, Manjula Canagaratna, Jordan E. Krechmer, Qi Zhang, Markku Kulmala, Juha Kangasluoma, Douglas Worsnop, and Mikael Ehn
Atmos. Meas. Tech., 17, 1527–1543, https://doi.org/10.5194/amt-17-1527-2024, https://doi.org/10.5194/amt-17-1527-2024, 2024
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Organic aerosol constitutes a significant portion of atmospheric fine particles but is less characterized due to its vast number of constituents. Recently, we developed a system for online measurements of particle-phase highly oxygenated organic molecules (HOMs). In this work, we systematically characterized the system, developed a new unit to enhance its performance, and demonstrated the essential role of thermograms in inferring volatility and quantifying HOMs in organic aerosols.
Xubing Du, Qinhui Xie, Qing Huang, Xuan Li, Junlin Yang, Zhihui Hou, Jingjing Wang, Xue Li, Zhen Zhou, Zhengxu Huang, Wei Gao, and Lei Li
Atmos. Meas. Tech., 17, 1037–1050, https://doi.org/10.5194/amt-17-1037-2024, https://doi.org/10.5194/amt-17-1037-2024, 2024
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Currently, the limitations of single-particle mass spectrometry detection capabilities render it not yet well suited for analyzing complex aerosol components in low-concentration environments. In this study, a new high-performance single-particle aerosol mass spectrometer (HP-SPAMS) is developed to enhance instrument performance regarding the number of detected particles, transmission efficiency, resolution, and sensitivity, which will help in aerosol science.
Zhengning Xu, Jian Gao, Zhuanghao Xu, Michel Attoui, Xiangyu Pei, Mario Amo-González, Kewei Zhang, and Zhibin Wang
Atmos. Meas. Tech., 16, 5995–6006, https://doi.org/10.5194/amt-16-5995-2023, https://doi.org/10.5194/amt-16-5995-2023, 2023
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Planar differential mobility analyzers (DMAs) have higher ion transmission efficiency and sizing resolution compared to cylindrical DMAs and are more suitable for use with mass spectrometers (MSs). Performance of the latest planar DMA (P5) was characterized. Sizing resolution and ion transmission efficiency were 5–16 times and ∼10 times higher than cylindrical DMAs. Sulfuric acid clusters were measured by DMA(P5)-MSs. This technique can be applied for natural products and biomolecule analysis.
Virginia Vernocchi, Elena Abd El, Marco Brunoldi, Silvia Giulia Danelli, Elena Gatta, Tommaso Isolabella, Federico Mazzei, Franco Parodi, Paolo Prati, and Dario Massabò
Atmos. Meas. Tech., 16, 5479–5493, https://doi.org/10.5194/amt-16-5479-2023, https://doi.org/10.5194/amt-16-5479-2023, 2023
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Bioaerosol are airborne particles or droplets that contain living organisms or biological materials, such as bacteria, viruses, fungi, pollen, or other organic matter. The study of the relationship between bioaerosol viability and air quality or meteorological conditions is an open field, and running experiments of the bioareosol viability in an atmospheric simulation chamber gives the possibility to set up well-defined conditions to evaluate the interaction between bioaerosol and pollutants.
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.
Sophie A. Mills, Adam Milsom, Christian Pfrang, A. Rob MacKenzie, and Francis D. Pope
Atmos. Meas. Tech., 16, 4885–4898, https://doi.org/10.5194/amt-16-4885-2023, https://doi.org/10.5194/amt-16-4885-2023, 2023
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Pollen grains are important components of the atmosphere and have the potential to impact upon cloud processes via their ability to help in the formation of rain droplets. This study investigates the hygroscopicity of two different pollen species using an acoustic levitator. Pollen grains are levitated, and their response to changes in relative humidity is investigated. A key advantage of this method is that it is possible study pollen shape under varying environmental conditions.
Taomou Zong, Zhijun Wu, Junrui Wang, Kai Bi, Wenxu Fang, Yanrong Yang, Xuena Yu, Zhier Bao, Xiangxinyue Meng, Yuheng Zhang, Song Guo, Yang Chen, Chunshan Liu, Yue Zhang, Shao-Meng Li, and Min Hu
Atmos. Meas. Tech., 16, 3679–3692, https://doi.org/10.5194/amt-16-3679-2023, https://doi.org/10.5194/amt-16-3679-2023, 2023
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This study developed and characterized an indoor chamber system (AIR) to simulate atmospheric multiphase chemistry processes. The AIR chamber can accurately control temperature and relative humidity (RH) over a broad range and simulate diurnal variation of ambient atmospheric RH. The aerosol generation unit can generate organic-coating seed particles with different phase states. The AIR chamber demonstrates high-quality performance in simulating secondary aerosol formation.
Marife B. Anunciado, Miranda De Boskey, Laura Haines, Katarina Lindskog, Tracy Dombek, Satoshi Takahama, and Ann M. Dillner
Atmos. Meas. Tech., 16, 3515–3529, https://doi.org/10.5194/amt-16-3515-2023, https://doi.org/10.5194/amt-16-3515-2023, 2023
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Organic sulfur compounds are used to identify sources and atmospheric processing of aerosol. Our paper evaluates the potential of using a non-destructive measurement technique to measure organic sulfur compounds in filter samples by assessing their chemical stability over time. Some were stable, but some evaporated or changed chemically. Future work includes evaluating the stability and potential interference of multiple organic sulfur compounds in laboratory mixtures and ambient aerosol.
Shipeng Kang, Tongzhu Yu, Yixin Yang, Jiguang Wang, Huaqiao Gui, Jianguo Liu, and Da-Ren Chen
Atmos. Meas. Tech., 16, 3245–3255, https://doi.org/10.5194/amt-16-3245-2023, https://doi.org/10.5194/amt-16-3245-2023, 2023
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A new aerosol electrometer, the thermal precipitation aerosol electrometer (TPAE), was designed for particles in sizes less than 300 nm, and its prototype performance was experimentally evaluated. The TPAE combines the thermal precipitator in the disk-to-disk configuration with a microcurrent measurement circuit board (i.e., pre-amplifier) for measuring the current carried by collected particles. Our performance study shows that the TPAE performance is consistent with the reference.
Battist Utinger, Steven John Campbell, Nicolas Bukowiecki, Alexandre Barth, Benjamin Gfeller, Ray Freshwater, Hans-Rudolf Rüegg, and Markus Kalberer
Atmos. Meas. Tech., 16, 2641–2654, https://doi.org/10.5194/amt-16-2641-2023, https://doi.org/10.5194/amt-16-2641-2023, 2023
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Exposure to atmospheric aerosols can lead to adverse health effect, but particle components responsible for this are unknown. Redox-active compounds, some with very short lifetimes, are considered to be a toxic class of compounds in particles. We developed the first online field instrument to quantify short-lived and stable redox-active compounds with a physiological assay based on ascorbic acid and a high time resolution and detection limits to allow measurements at unpolluted locations.
Ella Häkkinen, Jian Zhao, Frans Graeffe, Nicolas Fauré, Jordan E. Krechmer, Douglas Worsnop, Hilkka Timonen, Mikael Ehn, and Juha Kangasluoma
Atmos. Meas. Tech., 16, 1705–1721, https://doi.org/10.5194/amt-16-1705-2023, https://doi.org/10.5194/amt-16-1705-2023, 2023
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Highly oxygenated compounds contribute to the formation and growth of atmospheric organic aerosol and thus impact the global climate. Knowledge of their transformations and fate after condensing into the particle phase has been limited by the lack of suitable detection techniques. Here, we present an online method for measuring highly oxygenated compounds from organic aerosol. We evaluate the performance of the method and demonstrate that the method is applicable to different organic species.
Julia Pikmann, Lasse Moormann, Frank Drewnick, and Stephan Borrmann
Atmos. Meas. Tech., 16, 1323–1341, https://doi.org/10.5194/amt-16-1323-2023, https://doi.org/10.5194/amt-16-1323-2023, 2023
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Aerosols measured in complex environments are usually a mixture of emissions from different sources. To characterize sources individually, we developed a sampling system for particles and organic trace gases which is coupled to real-time data of physical and chemical aerosol properties, gas concentrations, and meteorological variables. Using suitable sampling conditions for individual aerosols which are compared with the real-time data the desired aerosols are sampled separately from each other.
Christopher R. Niedek, Fan Mei, Maria A. Zawadowicz, Zihua Zhu, Beat Schmid, and Qi Zhang
Atmos. Meas. Tech., 16, 955–968, https://doi.org/10.5194/amt-16-955-2023, https://doi.org/10.5194/amt-16-955-2023, 2023
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This novel micronebulization aerosol mass spectrometry (MS) technique requires a low sample volume (10 μL) and can quantify nanogram levels of organic and inorganic particulate matter (PM) components when used with 34SO4. This technique was successfully applied to PM samples collected from uncrewed atmospheric measurement platforms and provided chemical information that agrees well with real-time data from a co-located aerosol chemical speciation monitor and offline data from secondary ion MS.
Martin Rauber, Gary Salazar, Karl Espen Yttri, and Sönke Szidat
Atmos. Meas. Tech., 16, 825–844, https://doi.org/10.5194/amt-16-825-2023, https://doi.org/10.5194/amt-16-825-2023, 2023
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Carbon-containing aerosols from ambient air are analysed for radioactive isotope radiocarbon to determine the contribution from fossil-fuel emissions. Light-absorbing soot-like aerosols are isolated by water extraction and thermal separation. This separation is affected by artefacts, for which we developed a new correction method. The investigation of aerosols from the Arctic shows that our approach works well for such samples, where many artefacts are expected.
Alain Miffre, Danaël Cholleton, Clément Noël, and Patrick Rairoux
Atmos. Meas. Tech., 16, 403–417, https://doi.org/10.5194/amt-16-403-2023, https://doi.org/10.5194/amt-16-403-2023, 2023
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The depolarization ratio of hematite, silica, Arizona and Asian dust is evaluated in a lab with a π-polarimeter operating at lidar 180 ° and at (355, 532) nm wavelengths. The hematite depolarization equals (10±1) % at 355 nm for coarser particles, while that of silica is (33±1) %. This huge difference is explained by accounting for the high imaginary part of the hematite complex refractive index, thus revealing the key role played by light absorption in mineral dust lidar depolarization.
Miriam Chacón-Mateos, Bernd Laquai, Ulrich Vogt, and Cosima Stubenrauch
Atmos. Meas. Tech., 15, 7395–7410, https://doi.org/10.5194/amt-15-7395-2022, https://doi.org/10.5194/amt-15-7395-2022, 2022
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The study evaluates a low-cost dryer to avoid the negative effect of hygroscopic growth and fog droplets in the particulate matter (PM) concentrations of sensors. The results show a reduction in the overestimation of the PM but also an underestimation compared to reference devices. Special care is needed when designing a dryer as high temperatures change the sampled air by evaporating the most volatile particulate species. Low-cost dryers are very promising for different sensor applications.
Svetlana Sofieva, Eija Asmi, Nina S. Atanasova, Aino E. Heikkinen, Emeline Vidal, Jonathan Duplissy, Martin Romantschuk, Rostislav Kouznetsov, Jaakko Kukkonen, Dennis H. Bamford, Antti-Pekka Hyvärinen, and Mikhail Sofiev
Atmos. Meas. Tech., 15, 6201–6219, https://doi.org/10.5194/amt-15-6201-2022, https://doi.org/10.5194/amt-15-6201-2022, 2022
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A new bubble-generating glass chamber design with an extensive set of aerosol production experiments is presented to re-evaluate bubble-bursting-mediated aerosol production as a function of water parameters: bubbling air flow, water salinity, and temperature. Our main findings suggest modest dependence of aerosol production on the water salinity and a strong dependence on temperature below ~ 10 °C.
Kristian J. Kiland, Kevin L. Marroquin, Natalie R. Smith, Shaun Xu, Sergey A. Nizkorodov, and Allan K. Bertram
Atmos. Meas. Tech., 15, 5545–5561, https://doi.org/10.5194/amt-15-5545-2022, https://doi.org/10.5194/amt-15-5545-2022, 2022
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Information on the viscosity of secondary organic aerosols is needed when making air quality, climate, and atmospheric chemistry predictions. Viscosity depends on temperature, so we developed a new method for measuring the temperature-dependent viscosity of small samples. As an application of the method, we measured the viscosity of farnesene secondary organic aerosol at different temperatures.
Sabin Kasparoglu, Mohammad Maksimul Islam, Nicholas Meskhidze, and Markus D. Petters
Atmos. Meas. Tech., 15, 5007–5018, https://doi.org/10.5194/amt-15-5007-2022, https://doi.org/10.5194/amt-15-5007-2022, 2022
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A modified version of a Handix Scientific printed optical particle spectrometer is introduced. The paper presents characterization experiments, including concentration, size, and time responses. Integration of an external multichannel analyzer card removes counting limitations of the original instrument. It is shown that the high-resolution light-scattering amplitude data can be used to sense particle-phase transitions.
Nikunj Dudani and Satoshi Takahama
Atmos. Meas. Tech., 15, 4693–4707, https://doi.org/10.5194/amt-15-4693-2022, https://doi.org/10.5194/amt-15-4693-2022, 2022
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We designed and fabricated an aerosol collector with high collection efficiency that enables quantitative infrared spectroscopy analysis. By collecting particles on optical windows, typical substrate interferences are eliminated. New methods for fabricating aerosol devices using 3D printing with post-treatment to reduce the time and cost of prototyping are described.
Mao Du, Aristeidis Voliotis, Yunqi Shao, Yu Wang, Thomas J. Bannan, Kelly L. Pereira, Jacqueline F. Hamilton, Carl J. Percival, M. Rami Alfarra, and Gordon McFiggans
Atmos. Meas. Tech., 15, 4385–4406, https://doi.org/10.5194/amt-15-4385-2022, https://doi.org/10.5194/amt-15-4385-2022, 2022
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Atmospheric chemistry plays a key role in the understanding of aerosol formation and air pollution. We designed chamber experiments for the characterization of secondary organic aerosol (SOA) from a biogenic precursor with inorganic seed. Our results highlight the advantages of a combination of online FIGAERO-CIMS and offline LC-Orbitrap MS analytical techniques to characterize the chemical composition of SOA in chamber studies.
Chuan Ping Lee, Mihnea Surdu, David M. Bell, Josef Dommen, Mao Xiao, Xueqin Zhou, Andrea Baccarini, Stamatios Giannoukos, Günther Wehrle, Pascal André Schneider, Andre S. H. Prevot, Jay G. Slowik, Houssni Lamkaddam, Dongyu Wang, Urs Baltensperger, and Imad El Haddad
Atmos. Meas. Tech., 15, 3747–3760, https://doi.org/10.5194/amt-15-3747-2022, https://doi.org/10.5194/amt-15-3747-2022, 2022
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Real-time detection of both the gas and particle phase is needed to elucidate the sources and chemical reaction pathways of organic vapors and particulate matter. The Dual-EESI was developed to measure gas- and particle-phase species to provide new insights into aerosol sources or formation mechanisms. After characterizing the relative gas and particle response factors of EESI via organic aerosol uptake experiments, the Dual-EESI is more sensitive toward gas-phase analyes.
Martin I. Daily, Mark D. Tarn, Thomas F. Whale, and Benjamin J. Murray
Atmos. Meas. Tech., 15, 2635–2665, https://doi.org/10.5194/amt-15-2635-2022, https://doi.org/10.5194/amt-15-2635-2022, 2022
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Mineral dust and particles of biological origin are important types of ice-nucleating particles (INPs) that can trigger ice formation of supercooled cloud droplets. Heat treatments are used to detect the presence of biological INPs in samples collected from the environment as the activity of mineral INPs is assumed unchanged, although not fully assessed. We show that the ice-nucleating ability of some minerals can change after heating and discuss how INP heat tests should be interpreted.
Jiyan Wu, Chi Yang, Chunyan Zhang, Fang Cao, Aiping Wu, and Yanlin Zhang
Atmos. Meas. Tech., 15, 2623–2633, https://doi.org/10.5194/amt-15-2623-2022, https://doi.org/10.5194/amt-15-2623-2022, 2022
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We introduced an online method to simultaneously determine the content of inorganic salt ions and reactive oxygen species (ROS) in PM2.5 hour by hour. We verified the accuracy and precision of the instrument. And we got the daily changes in ROS and the main sources that affect ROS. This breakthrough enables the quantitative assessment of atmospheric particulate matter ROS at the diurnal scale, providing an effective tool to study sources and environmental impacts of ROS.
Virginia Vernocchi, Marco Brunoldi, Silvia G. Danelli, Franco Parodi, Paolo Prati, and Dario Massabò
Atmos. Meas. Tech., 15, 2159–2175, https://doi.org/10.5194/amt-15-2159-2022, https://doi.org/10.5194/amt-15-2159-2022, 2022
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The performance of a mini inverted soot generator was investigated at a simulation chamber facility by studying the soot generated by ethylene and propane combustion, together with the number, size, optical properties, and EC / OC concentrations. Mass absorption coefficients and Ångström absorption exponents are compatible with the literature, with some differences. The characterization of MISG soot particles is fundamental to design and perform experiments in atmospheric simulation chambers.
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.
Danaël Cholleton, Émilie Bialic, Antoine Dumas, Pascal Kaluzny, Patrick Rairoux, and Alain Miffre
Atmos. Meas. Tech., 15, 1021–1032, https://doi.org/10.5194/amt-15-1021-2022, https://doi.org/10.5194/amt-15-1021-2022, 2022
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While pollen impacts public health and the Earth’s climate, the identification of each pollen taxon remains challenging. In this context, a laboratory evaluation of the polarimetric light-scattering characteristics of ragweed, ash, birch and pine pollen, when embedded in ambient air, is here performed at two wavelengths. Interestingly, the achieved precision of the retrieved scattering matrix elements allows unequivocal light scattering characteristics of each studied taxon to be identified.
Kanishk Gohil and Akua A. Asa-Awuku
Atmos. Meas. Tech., 15, 1007–1019, https://doi.org/10.5194/amt-15-1007-2022, https://doi.org/10.5194/amt-15-1007-2022, 2022
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This work develops a methodology and software to study and analyze the cloud-droplet-forming ability of aerosols with an aerodynamic aerosol classifier (AAC). This work quantifies the uncertainties in size-resolved measurements and subsequent uncertainties propagated to cloud droplet parameterizations. Lastly, we present the best practices for AAC cloud droplet measurement.
Yunqi Shao, Yu Wang, Mao Du, Aristeidis Voliotis, M. Rami Alfarra, Simon P. O'Meara, S. Fiona Turner, and Gordon McFiggans
Atmos. Meas. Tech., 15, 539–559, https://doi.org/10.5194/amt-15-539-2022, https://doi.org/10.5194/amt-15-539-2022, 2022
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A comprehensive description and characterisation of the Manchester Aerosol Chamber (MAC) was conducted. The MAC has good temperature and relative humidity homogeneity, fast mixing times, and comparable losses of gases and particles with other chambers. The MAC's bespoke control system allows improved duty cycles and repeatable experiments. Moreover, the effect of contamination on performance was also investigated. It is highly recommended to regularly track the chamber's performance.
Dina Alfaouri, Monica Passananti, Tommaso Zanca, Lauri Ahonen, Juha Kangasluoma, Jakub Kubečka, Nanna Myllys, and Hanna Vehkamäki
Atmos. Meas. Tech., 15, 11–19, https://doi.org/10.5194/amt-15-11-2022, https://doi.org/10.5194/amt-15-11-2022, 2022
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To study what is happening in the atmosphere, it is important to be able to measure the molecules and clusters present in it. In our work, we studied an artifact that happens inside a mass spectrometer, in particular the fragmentation of clusters. We were able to quantify the fragmentation and retrieve the correct concentration and composition of the clusters using our dual (experimental and theoretical) approach.
Sudheer Salana, Yixiang Wang, Joseph V. Puthussery, and Vishal Verma
Atmos. Meas. Tech., 14, 7579–7593, https://doi.org/10.5194/amt-14-7579-2021, https://doi.org/10.5194/amt-14-7579-2021, 2021
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Oxidative potential (OP) of particulate matter (PM) is an important indicator of PM toxicity. However, no automated instrument has ever been developed to provide a rapid high-throughput analysis of cell-based OP measurements. Here, we developed a semi-automated instrument, the first of its kind, for measuring oxidative potential using rat alveolar cells. We also developed a dataset on the intrinsic cellular OP of several compounds commonly known to be present in ambient PM.
Kevin B. Fischer and Giuseppe A. Petrucci
Atmos. Meas. Tech., 14, 7565–7577, https://doi.org/10.5194/amt-14-7565-2021, https://doi.org/10.5194/amt-14-7565-2021, 2021
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The viscosity of organic particles in atmospheric aerosol is sometimes correlated to bounce factor. It is generally accepted that more viscous particles will be more likely to bounce following acceleration toward and impaction on a surface. We demonstrate that use of multi-stage low-pressure impactors for this purpose may result in measurement artifacts that depend on chemical composition, particle size, and changing relative humidity. A hypothesis for the observed effect is presented.
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Short summary
Polarimetric data, i.e., the angular and polarization dependence of light scattering by aerosols, contain ample information on optical and microphysical properties. Retrieval of these properties is a central approach in aerosol remote sensing. We present a description, calibration, validation, and a first application of a new benchtop polar nephelometer, which provides in situ polarimetric measurements of an aerosol. Such data facilitate agreement between retrieval results and independent data.
Polarimetric data, i.e., the angular and polarization dependence of light scattering by...
