Articles | Volume 19, issue 5
https://doi.org/10.5194/amt-19-1611-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/amt-19-1611-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
04 Mar 2026
Research article |
| 04 Mar 2026
| 04 Mar 2026
Hygroscopic enhancement of suburban aerosol light scattering measured using a single-nephelometer system in Central Europe
Institute of Chemical Process Fundamentals of the Czech Academy of Sciences, Prague, 16500, Czech Republic
Global Change Research Institute of the Czech Academy of Sciences, Brno, 60300, Czech Republic
RECETOX, Faculty of Science, Masaryk University, Brno, 61137, Czech Republic
Jakub Ondráček
Institute of Chemical Process Fundamentals of the Czech Academy of Sciences, Prague, 16500, Czech Republic
Naděžda Zíková
Institute of Chemical Process Fundamentals of the Czech Academy of Sciences, Prague, 16500, Czech Republic
Petr Roztočil
Institute of Chemical Process Fundamentals of the Czech Academy of Sciences, Prague, 16500, Czech Republic
Petr Vodička
Institute of Chemical Process Fundamentals of the Czech Academy of Sciences, Prague, 16500, Czech Republic
Roman Prokeš
Global Change Research Institute of the Czech Academy of Sciences, Brno, 60300, Czech Republic
RECETOX, Faculty of Science, Masaryk University, Brno, 61137, Czech Republic
Ivan Holoubek
Global Change Research Institute of the Czech Academy of Sciences, Brno, 60300, Czech Republic
RECETOX, Faculty of Science, Masaryk University, Brno, 61137, Czech Republic
deceased
Vladimír Ždímal
Institute of Chemical Process Fundamentals of the Czech Academy of Sciences, Prague, 16500, Czech Republic
Related authors
No articles found.
Aino Ovaska, Daniel Holmberg, Elio Rauth, Mansour Alghamdi, Paulo Artaxo, Eija Asmi, John Backman, Benjamin Bergmans, Matthew Boyer, Liezl Bredenkamp, Maurizio Busetto, Delano Campos De Oliveira, Juan Andrés Casquero-Vera, Darius Ceburnis, Tak Chan, Tommy Chan, Sebastien Conil, Daniele Contini, Suzanne Crumeyrolle, Valentin Duflot, Kostas Eleftheriadis, Johan Esveld, Ekaterina Ezhova, Markus Fiebig, Shahzad Gani, Olga Garmash, Francisco Gómez-Moreno, Roy M. Harrison, Andras Hoffer, Rakesh Hooda, Antti Hyvärinen, Tareq Hussein, Jorma Joutsensaari, Nikos Kalivitis, Heinz Kaminski, Jutta Kesti, Radovan Krejci, Adam Kristensson, Chongai Kuang, Markku Kulmala, Lauri Laakso, Ari Leskinen, Heikki Lihavainen, Andreas Massling, Maik Merkel, Steffen Noe, Jakub Ondracek, Noemí Perez, Jean-Eudes Petit, Tuukka Petäjä, Michael Pikridas, Christopher Pöhlker, Mira Pöhlker, Jean-Philippe Putaud, Ximeng Qi, Cristina Reche, Sergio Rodríguez, Petr Roztocil, Jean Sciare, Karine Sellegri, Dongjie Shang, Ashish Singh, Mikko Sipilä, Henrik Skov, Mar Sorribas, Tamanna Subba, Junying Sun, Peter Tunved, Ville Vakkari, Pieter G. Van Zyl, Aki Virkkula, Jens Voigtländer, Kay Weinhold, Alfred Wiedensohler, Hee-Jung Yoo, Putian Zhou, Kai Puolamäki, Tuomo Nieminen, Veli-Matti Kerminen, Victoria A. Sinclair, and Pauli Paasonen
Earth Syst. Sci. Data Discuss., https://doi.org/10.5194/essd-2026-415, https://doi.org/10.5194/essd-2026-415, 2026
Preprint under review for ESSD
Short summary
Short summary
All clouds form around aerosol particles, and their abundance influences cloud properties. In turn, clouds affect climate by changing how energy moves through the atmosphere, making them important for climate change. To better understand these interactions, we need accurate information on how many aerosol particles are in the atmosphere. Therefore, we have developed a new 21-year global dataset of particle concentrations relevant for cloud formation.
Shubhi Arora, Laurent Poulain, Radek Lhotka, Petr Vodička, Saliou Mbengue, Petra Pokorná, Jaroslav Schwarz, Naděžda Zíková, Jakub Ondráček, Vladimír Ždímal, and Hartmut Herrmann
EGUsphere, https://doi.org/10.5194/egusphere-2026-2028, https://doi.org/10.5194/egusphere-2026-2028, 2026
This preprint is open for discussion and under review for Atmospheric Measurement Techniques (AMT).
Short summary
Short summary
Accurate air pollution data is essential for effective policy, yet this study shows that common measurement methods can disagree under real-world conditions. Across three European sites, results matched in summer but diverged in winter, especially during combustion related pollution. The findings identify when measurements are reliable and provide practical guidance to improve monitoring, ensuring more robust data for air quality regulation and public health protection.
Herbert G. Hartl, Janne Lampilahti, Rima Baalbaki, Lauri Ahonen, Tommy Chan, Tinghang Zhang, Joonas Vanhanen, Joonas Purén, Gerhard Steiner, Sebastian Schmitt, Torsten Tritscher, Amine Koched, Manuel Granzin, Petr Roztocil, Silja Häme, Tuukka Petäjä, and Katrianne Lehtipalo
Aerosol Research, 4, 133–152, https://doi.org/10.5194/ar-4-133-2026, https://doi.org/10.5194/ar-4-133-2026, 2026
Short summary
Short summary
Small airborne particles influence how clouds form and how they affect the climate. Our study compared eight different instruments that measure the size distributions of these particles to understand the instruments' strengths and weaknesses. We found that some systems are more accurate, whereas others are more sensitive at tiny sizes. These results will help to improve future monitoring of air quality and climate processes.
Kajal Julaha, Vladimír Ždímal, Saliou Mbengue, David Brus, and Naděžda Zíková
Atmos. Chem. Phys., 25, 17933–17951, https://doi.org/10.5194/acp-25-17933-2025, https://doi.org/10.5194/acp-25-17933-2025, 2025
Short summary
Short summary
This study used drones for vertical profiling of black carbon and particle number at rural and urban sites in Czechia. With aerosol drying, drone measurements matched with fixed instruments; without drying, black carbon was significantly overestimated. Rural profiles were more stratified in winter, while urban summer profiles were well-mixed. These findings can help improve air-quality monitoring and policies by capturing vertical pollution structures that ground stations cannot resolve.
Aino Ovaska, Elio Rauth, Daniel Holmberg, Paulo Artaxo, John Backman, Benjamin Bergmans, Don Collins, Marco Aurélio Franco, Shahzad Gani, Roy M. Harrison, Rakesh K. Hooda, Tareq Hussein, Antti-Pekka Hyvärinen, Kerneels Jaars, Adam Kristensson, Markku Kulmala, Lauri Laakso, Ari Laaksonen, Nikolaos Mihalopoulos, Colin O'Dowd, Jakub Ondracek, Tuukka Petäjä, Kristina Plauškaitė, Mira Pöhlker, Ximeng Qi, Peter Tunved, Ville Vakkari, Alfred Wiedensohler, Kai Puolamäki, Tuomo Nieminen, Veli-Matti Kerminen, Victoria A. Sinclair, and Pauli Paasonen
Aerosol Research, 3, 589–618, https://doi.org/10.5194/ar-3-589-2025, https://doi.org/10.5194/ar-3-589-2025, 2025
Short summary
Short summary
We trained machine learning models to estimate the number of aerosol particles large enough to form clouds and generated daily estimates for the entire globe. The models performed well in many continental regions but struggled in remote and marine areas. Still, this approach offers a way to quantify these particles in areas that lack direct measurements, helping us understand their influence on clouds and climate on a global scale.
Laurence C. Windell, Saliou Mbengue, Petra Pokorná, Jaroslav Schwarz, André S. H. Prévôt, Manousos I. Manousakas, Stefanos Papagiannis, Jakub Ondráček, Roman Prokeš, and Vladimir Ždímal
Atmos. Meas. Tech., 18, 7021–7038, https://doi.org/10.5194/amt-18-7021-2025, https://doi.org/10.5194/amt-18-7021-2025, 2025
Short summary
Short summary
In this work, we compare the two most widely used online XRF monitors for ambient elemental analysis, the Xact625i and PX-375. We found strong correlations between the online instruments and the reference method (better so for the Xact625i), while in terms of absolute concentrations, some elements were over- and underestimated. Overall, we determined both instruments can be used as powerful tools to produce high-time resolution elemental data for use in air quality monitoring.
Lukáš Bartík, Peter Huszár, Jan Peiker, Jan Karlický, Ondřej Vlček, and Petr Vodička
Atmos. Chem. Phys., 25, 15301–15328, https://doi.org/10.5194/acp-25-15301-2025, https://doi.org/10.5194/acp-25-15301-2025, 2025
Short summary
Short summary
This study investigates how to better understand and predict organic aerosols, which are tiny particles in the air that can affect our health and climate. By using advanced computer models, we examined the impact of different emissions and environmental conditions on these aerosols in Central Europe. Our findings show that including specific emissions significantly improved the accuracy of our predictions.
Hanna Wiedenhaus, Roland Schrödner, Ralf Wolke, Marie L. Luttkus, Shubhi Arora, Laurent Poulain, Radek Lhotka, Petr Vodička, Jaroslav Schwarz, Petra Pokorna, Jakub Ondráček, Vladimir Ždímal, Hartmut Herrmann, and Ina Tegen
Atmos. Chem. Phys., 25, 12893–12922, https://doi.org/10.5194/acp-25-12893-2025, https://doi.org/10.5194/acp-25-12893-2025, 2025
Short summary
Short summary
This study examines winter air quality in central Europe, focusing on the impact of domestic heating. Using a chemical transport model and measurements, it was found that the model underestimated organic particle concentrations. This was due to an underestimation of gases from domestic heating that form secondary organic particles. Improving the model by increasing these emissions and the particle formation led to better results, demonstrating the important role of heating emissions in winter.
Petr Vodička, Kimitaka Kawamura, Bhagawati Kunwar, Lin Huang, Dhananjay Kumar, Md. Mozammel Haque, Ambarish Pokhrel, Sangeeta Sharma, and Leonard Barrie
Atmos. Chem. Phys., 25, 10215–10228, https://doi.org/10.5194/acp-25-10215-2025, https://doi.org/10.5194/acp-25-10215-2025, 2025
Short summary
Short summary
Carbonate carbon (CC) is not negligible in Arctic total suspended particles (TSPs). If not considered, CC biases the contribution of elemental and organic carbon. CC content in TSPs was strongly reflected in the δ13C values of total carbon (TC). The carbon contribution from CaCO3 supports the strong dependence of CC and δ13C on Ca. Finally, two hypothetical CC sources were identified based on the analysis of air mass back trajectories: dust resuspension and marine microorganisms.
Teemu Lepistö, Henna Lintusaari, Laura Salo, Ville Silvonen, Luis M. F. Barreira, Jussi Hoivala, Lassi Markkula, Jarkko V. Niemi, Jakub Ondracek, Kimmo Teinilä, Hanna E. Manninen, Sanna Saarikoski, Hilkka Timonen, Miikka Dal Maso, and Topi Rönkkö
Aerosol Research, 2, 271–289, https://doi.org/10.5194/ar-2-271-2024, https://doi.org/10.5194/ar-2-271-2024, 2024
Short summary
Short summary
The performances of different particle lung-deposited surface area (LDSAal) measurement methods (Partector, ELPI+, SMPS/DMPS) were compared in ambient conditions. As LDSAal is a health-relevant metric and rather easy to utilise in air quality monitoring, it is crucial to know how the different methods agree, as there are clear differences in their operation. In all, a comparison of different methods can be complicated; still, the methods agree rather well in terms of local pollution (< 400 nm).
Jean-Philippe Putaud, Enrico Pisoni, Alexander Mangold, Christoph Hueglin, Jean Sciare, Michael Pikridas, Chrysanthos Savvides, Jakub Ondracek, Saliou Mbengue, Alfred Wiedensohler, Kay Weinhold, Maik Merkel, Laurent Poulain, Dominik van Pinxteren, Hartmut Herrmann, Andreas Massling, Claus Nordstroem, Andrés Alastuey, Cristina Reche, Noemí Pérez, Sonia Castillo, Mar Sorribas, Jose Antonio Adame, Tuukka Petaja, Katrianne Lehtipalo, Jarkko Niemi, Véronique Riffault, Joel F. de Brito, Augustin Colette, Olivier Favez, Jean-Eudes Petit, Valérie Gros, Maria I. Gini, Stergios Vratolis, Konstantinos Eleftheriadis, Evangelia Diapouli, Hugo Denier van der Gon, Karl Espen Yttri, and Wenche Aas
Atmos. Chem. Phys., 23, 10145–10161, https://doi.org/10.5194/acp-23-10145-2023, https://doi.org/10.5194/acp-23-10145-2023, 2023
Short summary
Short summary
Many European people are still exposed to levels of air pollution that can affect their health. COVID-19 lockdowns in 2020 were used to assess the impact of the reduction in human mobility on air pollution across Europe by comparing measurement data with values that would be expected if no lockdown had occurred. We show that lockdown measures did not lead to consistent decreases in the concentrations of fine particulate matter suspended in the air, and we investigate why.
Jonas Elm, Aladár Czitrovszky, Andreas Held, Annele Virtanen, Astrid Kiendler-Scharr, Benjamin J. Murray, Daniel McCluskey, Daniele Contini, David Broday, Eirini Goudeli, Hilkka Timonen, Joan Rosell-Llompart, Jose L. Castillo, Evangelia Diapouli, Mar Viana, Maria E. Messing, Markku Kulmala, Naděžda Zíková, and Sebastian H. Schmitt
Aerosol Research, 1, 13–16, https://doi.org/10.5194/ar-1-13-2023, https://doi.org/10.5194/ar-1-13-2023, 2023
Petra Pokorná, Naděžda Zíková, Petr Vodička, Radek Lhotka, Saliou Mbengue, Adéla Holubová Šmejkalová, Véronique Riffault, Jakub Ondráček, Jaroslav Schwarz, and Vladimír Ždímal
Atmos. Chem. Phys., 22, 5829–5858, https://doi.org/10.5194/acp-22-5829-2022, https://doi.org/10.5194/acp-22-5829-2022, 2022
Short summary
Short summary
By examining individual episodes of high mass and number concentrations, we show that the seasonality in the physicochemical properties of aerosol particles was caused by the sources' diversity and was related to the different air masses and meteorology. We also confirmed the relation between particle size and age that is reflected in oxidation state and shape (difference in densities; effective vs. material). The results have general validity and thus transcend the study regional character.
Clémence Rose, Martine Collaud Coen, Elisabeth Andrews, Yong Lin, Isaline Bossert, Cathrine Lund Myhre, Thomas Tuch, Alfred Wiedensohler, Markus Fiebig, Pasi Aalto, Andrés Alastuey, Elisabeth Alonso-Blanco, Marcos Andrade, Begoña Artíñano, Todor Arsov, Urs Baltensperger, Susanne Bastian, Olaf Bath, Johan Paul Beukes, Benjamin T. Brem, Nicolas Bukowiecki, Juan Andrés Casquero-Vera, Sébastien Conil, Konstantinos Eleftheriadis, Olivier Favez, Harald Flentje, Maria I. Gini, Francisco Javier Gómez-Moreno, Martin Gysel-Beer, Anna Gannet Hallar, Ivo Kalapov, Nikos Kalivitis, Anne Kasper-Giebl, Melita Keywood, Jeong Eun Kim, Sang-Woo Kim, Adam Kristensson, Markku Kulmala, Heikki Lihavainen, Neng-Huei Lin, Hassan Lyamani, Angela Marinoni, Sebastiao Martins Dos Santos, Olga L. Mayol-Bracero, Frank Meinhardt, Maik Merkel, Jean-Marc Metzger, Nikolaos Mihalopoulos, Jakub Ondracek, Marco Pandolfi, Noemi Pérez, Tuukka Petäjä, Jean-Eudes Petit, David Picard, Jean-Marc Pichon, Veronique Pont, Jean-Philippe Putaud, Fabienne Reisen, Karine Sellegri, Sangeeta Sharma, Gerhard Schauer, Patrick Sheridan, James Patrick Sherman, Andreas Schwerin, Ralf Sohmer, Mar Sorribas, Junying Sun, Pierre Tulet, Ville Vakkari, Pieter Gideon van Zyl, Fernando Velarde, Paolo Villani, Stergios Vratolis, Zdenek Wagner, Sheng-Hsiang Wang, Kay Weinhold, Rolf Weller, Margarita Yela, Vladimir Zdimal, and Paolo Laj
Atmos. Chem. Phys., 21, 17185–17223, https://doi.org/10.5194/acp-21-17185-2021, https://doi.org/10.5194/acp-21-17185-2021, 2021
Short summary
Short summary
Aerosol particles are a complex component of the atmospheric system the effects of which are among the most uncertain in climate change projections. Using data collected at 62 stations, this study provides the most up-to-date picture of the spatial distribution of particle number concentration and size distribution worldwide, with the aim of contributing to better representation of aerosols and their interactions with clouds in models and, therefore, better evaluation of their impact on climate.
Cited articles
Alduchov, O. A. and Eskridge, R. E.: Magnus-Tetens formula, Asheville, 21 pp., https://doi.org/10.2172/548871, 1997.
Anderson, T. L. and Ogren, J. A.: Determining Aerosol Radiative Properties Using the TSI 3563 Integrating Nephelometer, Aerosol Sci. Tech., 29, 57–69, https://doi.org/10.1080/02786829808965551, 1998.
Anderson, T. L., Covert, D. S., Marshall, S., Laucks, M. L., Charlson, R. J., Waggoner, A. P., Ogren, J. A., Caldow, R., Holm, R. L., Quant, F. R., Sem, G. J., Wiendensholer, A., Ahlquist, N. A., and Bates, T. S.: Performance Characteristics of a High-Sensitivity, Three-Wavelength, Total Scatter/Backscatter Nephelometer, J. Atmos. Ocean. Tech., 13, 967–986, https://doi.org/10.1175/1520-0426(1996)013<0967:PCOAHS>2.0.CO;2, 1996.
Andrews, E., Sheridan, P. J., Fiebig, M., McComiskey, A., Ogren, J. A., Arnott, P., Covert, D., Elleman, R., Gasparini, R., Collins, D., Jonsson, H., Schmid, B., and Wang, J.: Comparison of methods for deriving aerosol asymmetry parameter, J. Geophys. Res.-Atmos., 111, D05S04, https://doi.org/10.1029/2004JD005734, 2006.
Andrews, E., Zieger, P., Titos, G., and Burgos, M.: Evaluation and improvement of the parameterization of aerosol hygroscopicity in global climate models using in-situ surface measurements, Final Report, https://doi.org/10.2172/1706478, 2021.
Aswini, A. R., Hegde, P., Nair, P. R., and Aryasree, S.: Seasonal changes in carbonaceous aerosols over a tropical coastal location in response to meteorological processes, Sci. Total Environ., 656, 1261–1279, https://doi.org/10.1016/J.SCITOTENV.2018.11.366, 2019.
Bauer, J. J., Yu, X.-Y., Cary, R., Laulainen, N., and Berkowitz, C.: Characterization of the sunset semi-continuous carbon aerosol analyzer, J. Air Waste Manage., 59, 826–833, https://doi.org/10.3155/1047-3289.59.7.826, 2009.
Boucher, O.: Atmospheric Aerosols, in: Atmospheric Aerosols, Springer Netherlands, Dordrecht, 9–24, https://doi.org/10.1007/978-94-017-9649-1_2, 2015.
Burgos, M. A., Andrews, E., Titos, G., Alados-Arboledas, L., Baltensperger, U., Day, D., Jefferson, A., Kalivitis, N., Mihalopoulos, N., Sherman, J., Sun, J., Weingartner, E., and Zieger, P.: A global view on the effect of water uptake on aerosol particle light scattering, Sci. Data, 6, 1–19, https://doi.org/10.1038/s41597-019-0158-7, 2019.
Burgos, M. A., Andrews, E., Titos, G., Benedetti, A., Bian, H., Buchard, V., Curci, G., Kipling, Z., Kirkevåg, A., Kokkola, H., Laakso, A., Letertre-Danczak, J., Lund, M. T., Matsui, H., Myhre, G., Randles, C., Schulz, M., van Noije, T., Zhang, K., Alados-Arboledas, L., Baltensperger, U., Jefferson, A., Sherman, J., Sun, J., Weingartner, E., and Zieger, P.: A global model–measurement evaluation of particle light scattering coefficients at elevated relative humidity, Atmos. Chem. Phys., 20, 10231–10258, https://doi.org/10.5194/acp-20-10231-2020, 2020.
Cappa, C. D., Kolesar, K. R., Zhang, X., Atkinson, D. B., Pekour, M. S., Zaveri, R. A., Zelenyuk, A., and Zhang, Q.: Understanding the optical properties of ambient sub- and supermicron particulate matter: results from the CARES 2010 field study in northern California, Atmos. Chem. Phys., 16, 6511–6535, https://doi.org/10.5194/acp-16-6511-2016, 2016.
Carrico, C. M., Kus, P., Rood, M. J., Quinn, P. K., Bates, T. S., Carrico, C., Kus, P., Rood, M. J., Quinn, P. K., and Bates, T. S.: Mixtures of pollution, dust, sea salt, and volcanic aerosol during ACE-Asia: Radiative properties as a function of relative humidity, J. Geophys. Res.-Atmos., 108, 8650, https://doi.org/10.1029/2003JD003405, 2003.
Carslaw, K. S., Gordon, H., Hamilton, D. S., Johnson, J. S., Regayre, L. A., Yoshioka, M., and Pringle, K. J.: Aerosols in the Pre-industrial Atmosphere, Curr. Clim. Chang. Reports, 31, 1–15, https://doi.org/10.1007/S40641-017-0061-2, 2017.
Cavalli, F., Viana, M., Yttri, K. E., Genberg, J., and Putaud, J.-P.: Toward a standardised thermal-optical protocol for measuring atmospheric organic and elemental carbon: the EUSAAR protocol, Atmos. Meas. Tech., 3, 79–89, https://doi.org/10.5194/amt-3-79-2010, 2010.
Cazorla, A., Bahadur, R., Suski, K. J., Cahill, J. F., Chand, D., Schmid, B., Ramanathan, V., and Prather, K. A.: Relating aerosol absorption due to soot, organic carbon, and dust to emission sources determined from in-situ chemical measurements, Atmos. Chem. Phys., 13, 9337–9350, https://doi.org/10.5194/acp-13-9337-2013, 2013.
Chan, M. N., Choi, M. Y., Ng, N. L., and Chan, C. K.: Hygroscopicity of water-soluble organic compounds in atmospheric aerosols: Amino acids and biomass burning derived organic species, Environ. Sci. Technol., 39, 1555–1562, https://doi.org/10.1021/ES049584L, 2005.
Czech statistical office: Population and Housing Census, https://geodata.csu.gov.cz/as/atlas/?xmax=2194777.485518976&ymax=6694180.788553198&xmin=1255519.2819509797&ymin=6135884.7339584185&wkid=102100 (last access: 13 December 2024), 2024.
Clarke, A. and Kapustin, V.: Hemispheric aerosol vertical profiles: Anthropogenic impacts on optical depth and cloud nuclei, Science, 329, 1488–1492, https://doi.org/10.1126/science.1188838, 2010.
Covert, D. S., Charlson, R. J., and Ahlquist, N. C.: A Study of the Relationship of Chemical Composition and Humidity to Light Scattering by Aerosols, J. Appl. Meteorol., 11, 968–976, https://doi.org/10.1175/1520-0450(1972)011<0968:asotro>2.0.co;2, 1972.
Dinar, E., Abo Riziq, A., Spindler, C., Erlick, C., Kiss, G., and Rudich, Y.: The complex refractive index of atmospheric and model humic-like substances (HULIS) retrieved by a cavity ring down aerosol spectrometer (CRD-AS), Faraday Discuss., 137, 279–295, https://doi.org/10.1039/B703111D, 2008.
Doherty, S. J.: A comparison and summary of aerosol optical properties as observed in situ from aircraft, ship, and land during ACE-Asia, J. Geophys. Res., 110, D04201, https://doi.org/10.1029/2004JD004964, 2005.
Donateo, A., Lo Feudo, T., Marinoni, A., Calidonna, C. R., Contini, D., and Bonasoni, P.: Long-term observations of aerosol optical properties at three GAW regional sites in the Central Mediterranean, Atmos. Res., 241, 104976, https://doi.org/10.1016/j.atmosres.2020.104976, 2020.
Draxler, R. R. and Hess, G. D.: An overview of the HYSPLIT_4 modelling system for trajectories, dispersion and deposition, Aust. Meteorol. Mag., 47, 295–308, https://doi.org/10.1071/ES98032, 1998.
Drinovec, L., Močnik, G., Zotter, P., Prévôt, A. S. H., Ruckstuhl, C., Coz, E., Rupakheti, M., Sciare, J., Müller, T., Wiedensohler, A., and Hansen, A. D. A.: The “dual-spot” Aethalometer: an improved measurement of aerosol black carbon with real-time loading compensation, Atmos. Meas. Tech., 8, 1965–1979, https://doi.org/10.5194/amt-8-1965-2015, 2015.
Fierz-Schmidhauser, R., Zieger, P., Gysel, M., Kammermann, L., DeCarlo, P. F., Baltensperger, U., and Weingartner, E.: Measured and predicted aerosol light scattering enhancement factors at the high alpine site Jungfraujoch, Atmos. Chem. Phys., 10, 2319–2333, https://doi.org/10.5194/acp-10-2319-2010, 2010.
Flemming, J., Benedetti, A., Inness, A., Engelen, R. J., Jones, L., Huijnen, V., Remy, S., Parrington, M., Suttie, M., Bozzo, A., Peuch, V.-H., Akritidis, D., and Katragkou, E.: The CAMS interim Reanalysis of Carbon Monoxide, Ozone and Aerosol for 2003–2015, Atmos. Chem. Phys., 17, 1945–1983, https://doi.org/10.5194/acp-17-1945-2017, 2017.
Foster, P., Storelvmo, T., Armour, K., Collins, W., Dufresne, J. L., Frame, D., Lunt, D. J., Mauritsen, T., Palmer, M. D., Watanabe, M., Wild, M., and Zhang, H.: The Earth's Energy Budget, Climate Feedbacks, and Climate Sensitivity, in: Climate Change 2021: The Physical Science Basis. Contribution of Working Group I to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change, Climate Change 2021 – The Physical Science Basis, Cambridge University Press, 923–1054, https://doi.org/10.1017/9781009157896.009, 2023.
Haywood, J. M. and Shine, K. P.: The effect of anthropogenic sulfate and soot aerosol on the clear sky planetary radiation budget, Geophys. Res. Lett., 22, 603–606, https://doi.org/10.1029/95GL00075, 1995.
Hegg, D. A., Covert, D. S., Rood, M. J., and Hobbs, P. V.: Measurements of aerosol optical properties in marine air, J. Geophys. Res.-Atmos., 101, 12893–12903, https://doi.org/10.1029/96JD00751, 1996.
Held, A., Zerrath, A., McKeon, U., Fehrenbach, T., Niessner, R., Plass-Dülmer, C., Kaminski, U., Berresheim, H., and Pöschl, U.: Aerosol size distributions measured in urban, rural and high-alpine air with an electrical low pressure impactor (ELPI), Atmos. Environ., 42, 8502–8512, https://doi.org/10.1016/j.atmosenv.2008.06.015, 2008.
Huang, W., Saathoff, H., Shen, X., Ramisetty, R., Leisner, T., and Mohr, C.: Seasonal characteristics of organic aerosol chemical composition and volatility in Stuttgart, Germany, Atmos. Chem. Phys., 19, 11687–11700, https://doi.org/10.5194/acp-19-11687-2019, 2019.
HYSPLIT model: https://www.ready.noaa.gov/HYSPLIT.php (last access: 13 June 2025).
IPCC: Climate Change 2021: The Physical Science Basis. Contribution of Working Group I to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change, edited by: Masson-Delmotte, V., Zhai, P., Pirani, A., Connors, S. L., Péan, C., Berger, S., Caus, N., Chen, Y., Goldfarb, L., Gomis, M. I., Huang, M., Leitzell, K., Lonnoy, E., Matthews, J. B. R., Maycock, T. K., Waterfield, T., Yelekçi, O., Yu, R., and Zhou, B., Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA, 3949 pp., https://doi.org/10.1017/9781009157896, 2023.
Kahn, R. A., Andrews, E., Brock, C. A., Chin, M., Feingold, G., Gettelman, A., Levy, R. C., Murphy, D. M., Nenes, A., Pierce, J. R., Popp, T., Redemann, J., Sayer, A. M., da Silva, A. M., Sogacheva, L., and Stier, P.: Reducing Aerosol Forcing Uncertainty by Combining Models With Satellite and Within-The-Atmosphere Observations: A Three-Way Street, Rev. Geophys., 61, https://doi.org/10.1029/2022RG000796, 2023.
Kang, H., Jung, C. H., Lee, B. Y., Krejci, R., Heslin-Rees, D., Aas, W., and Yoon, Y. J.: Aerosol hygroscopicity influenced by seasonal chemical composition variations in the Arctic region, J. Aerosol Sci., 186, 106551, https://doi.org/10.1016/j.jaerosci.2025.106551, 2025.
Kiehl, J. T. and Briegleb, B. P.: The Relative Roles of Sulfate Aerosols and Greenhouse Gases in Climate Forcing, Science, 260, 311–314, https://doi.org/10.1126/SCIENCE.260.5106.311, 1993.
Koop, T., Bookhold, J., Shiraiwa, M., and Pöschl, U.: Glass transition and phase state of organic compounds: dependency on molecular properties and implications for secondary organic aerosols in the atmosphere, Phys. Chem. Chem. Phys., 13, 19238–19255, https://doi.org/10.1039/C1CP22617G, 2011.
Kristensen, T. B., Wex, H., Nekat, B., Njgaard, J. K., Van Pinxteren, D., Lowenthal, D. H., Mazzoleni, L. R., Dieckmann, K., Bender Koch, C., Mentel, T. F., Herrmann, H., Gannet Hallar, A., Stratmann, F., and Bilde, M.: Hygroscopic growth and CCN activity of HULIS from different environments, J. Geophys. Res.-Atmos., 117, 22203, https://doi.org/10.1029/2012JD018249, 2012.
Liu, J. and Li, Z.: Significant Underestimation in the Optically Based Estimation of the Aerosol First Indirect Effect Induced by the Aerosol Swelling Effect, Geophys. Res. Lett., 45, 5690–5699, https://doi.org/10.1029/2018GL077679, 2018.
Liu, X. and Wang, J.: How important is organic aerosol hygroscopicity to aerosol indirect forcing?, https://doi.org/10.1088/1748-9326/5/4/044010, 2010.
Magee Scientific: User's manual for Aethalometer® Model AE33, 149, https://aerosolmageesci.com/products/aethalometer-ae33/ (last access: 10 June 2025) 2018.
Maskey, S., Chong, K. Y., Kim, G., Kim, J. S., Ali, A., and Park, K.: Effect of mixing structure on the hygroscopic behavior of ultrafine ammonium sulfate particles mixed with succinic acid and levoglucosan, Particuology, 13, 27–34, https://doi.org/10.1016/J.PARTIC.2013.08.004, 2014.
Massoli, P., Bates, T. S., Quinn, P. K., Lack, D. A., Baynard, T., Lerner, B. M., Tucker, S. C., Brioude, J., Stohl, A., and Williams, E. J.: Aerosol optical and hygroscopic properties during TexAQS-GoMACCS 2006 and their impact on aerosol direct radiative forcing, J. Geophys. Res.-Atmos., 114, 0–07, https://doi.org/10.1029/2008JD011604, 2009.
Mbengue, S., Zikova, N., Schwarz, J., Vodička, P., Šmejkalová, A. H., and Holoubek, I.: Mass absorption cross-section and absorption enhancement from long term black and elemental carbon measurements: A rural background station in Central Europe, Sci. Total Environ., 794, 1–14, https://doi.org/10.1016/j.scitotenv.2021.148365, 2021.
Müller, T. and Fiebig, M.: ACTRIS In Situ Aerosol: Guidelines for Manual QC of AE33 absorption photometer data, 9 pp., 2021.
Müller, T., Laborde, M., Kassell, G., and Wiedensohler, A.: Design and performance of a three-wavelength LED-based total scatter and backscatter integrating nephelometer, Atmos. Meas. Tech., 4, 1291–1303, https://doi.org/10.5194/amt-4-1291-2011, 2011.
Myhre, G., Shindell, D., Bréon, F.-M., Collins, W., Fuglestvedt, J., Huang, J., Koch, D., Lamarque, J.-F., Lee, D., Mendoza, B., Nakajima, T., Robock, A., Stephens, T., Takemura, T., and Zhang, H.: Anthropogenic and natural radiative forcing, in: Climate Change 2013 the Physical Science Basis: Working Group I Contribution to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change, vol. 9781107057, edited by: Stocker, T. F., Qin, D. G.-K. P., Tignor, M., Allen, S. K., Boschung, J., Nauels, A., Xia, Y., Bex, V., and Midgley, P. M., Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA, 659–740, https://doi.org/10.1017/CBO9781107415324.018, 2013.
Orozco, D., Beyersdorf, A. J., Ziemba, L. D., Berkoff, T., Zhang, Q., Delgado, R., Hennigan, C. J., Thornhill, K. L., Young, D. E., Parworth, C., Kim, H., and Hoff, R. M.: Hygrosopicity measurements of aerosol particles in the San Joaquin Valley, CA, Baltimore, MD, and Golden, CO, J. Geophys. Res.-Atmos., 121, 7344–7359, https://doi.org/10.1002/2015JD023971, 2016.
Pandolfi, M., Alados-Arboledas, L., Alastuey, A., Andrade, M., Angelov, C., Artiñano, B., Backman, J., Baltensperger, U., Bonasoni, P., Bukowiecki, N., Collaud Coen, M., Conil, S., Coz, E., Crenn, V., Dudoitis, V., Ealo, M., Eleftheriadis, K., Favez, O., Fetfatzis, P., Fiebig, M., Flentje, H., Ginot, P., Gysel, M., Henzing, B., Hoffer, A., Holubova Smejkalova, A., Kalapov, I., Kalivitis, N., Kouvarakis, G., Kristensson, A., Kulmala, M., Lihavainen, H., Lunder, C., Luoma, K., Lyamani, H., Marinoni, A., Mihalopoulos, N., Moerman, M., Nicolas, J., O'Dowd, C., Petäjä, T., Petit, J.-E., Pichon, J. M., Prokopciuk, N., Putaud, J.-P., Rodríguez, S., Sciare, J., Sellegri, K., Swietlicki, E., Titos, G., Tuch, T., Tunved, P., Ulevicius, V., Vaishya, A., Vana, M., Virkkula, A., Vratolis, S., Weingartner, E., Wiedensohler, A., and Laj, P.: A European aerosol phenomenology – 6: scattering properties of atmospheric aerosol particles from 28 ACTRIS sites, Atmos. Chem. Phys., 18, 7877–7911, https://doi.org/10.5194/acp-18-7877-2018, 2018.
Perrone, M. R., Romano, S., Genga, A., and Paladini, F.: Integration of optical and chemical parameters to improve the particulate matter characterization, Atmos. Res., 205, 93–106, https://doi.org/10.1016/j.atmosres.2018.02.015, 2018.
Pilat, M. J. and Charlson, R. J.: Theoretical and optical stud- ies of humidity effects on the size distribution of a hygroscopic aerosol, J. Rech. Atmosphériques, 2, 165–170, 1966.
Pöhlker, M. L., Pöhlker, C., Quaas, J., Mülmenstädt, J., Pozzer, A., Andreae, M. O., Artaxo, P., Block, K., Coe, H., Ervens, B., Gallimore, P., Gaston, C. J., Gunthe, S. S., Henning, S., Herrmann, H., Krüger, O. O., McFiggans, G., Poulain, L., Raj, S. S., Reyes-Villegas, E., Royer, H. M., Walter, D., Wang, Y., and Pöschl, U.: Global organic and inorganic aerosol hygroscopicity and its effect on radiative forcing, Nat. Commun., 14, 6139, https://doi.org/10.1038/s41467-023-41695-8, 2023.
Ray, A., Bhowmik, M., Hazra, A., and Pandithurai, G.: The influence of aerosol hygroscopicity on clouds and precipitation over Western Ghats, India, Q. J. Roy. Meteor. Soc., 150, 1473–1488, https://doi.org/10.1002/QJ.4654, 2024.
Ren, R., Li, Z., Yan, P., Wang, Y., Wu, H., Cribb, M., Wang, W., Jin, X., Li, Y., and Zhang, D.: Measurement report: The effect of aerosol chemical composition on light scattering due to the hygroscopic swelling effect, Atmos. Chem. Phys., 21, 9977–9994, https://doi.org/10.5194/acp-21-9977-2021, 2021.
Savadkoohi, M., Pandolfi, M., Favez, O., Putaud, J. P., Eleftheriadis, K., Fiebig, M., Hopke, P. K., Laj, P., Wiedensohler, A., Alados-Arboledas, L., Bastian, S., Chazeau, B., María, Á. C., Colombi, C., Costabile, F., Green, D. C., Hueglin, C., Liakakou, E., Luoma, K., Listrani, S., Mihalopoulos, N., Marchand, N., Močnik, G., Niemi, J. V., Ondráček, J., Petit, J. E., Rattigan, O. V., Reche, C., Timonen, H., Titos, G., Tremper, A. H., Vratolis, S., Vodička, P., Funes, E. Y., Zíková, N., Harrison, R. M., Petäjä, T., Alastuey, A., and Querol, X.: Recommendations for reporting equivalent black carbon (eBC) mass concentrations based on long-term pan-European in-situ observations, Environ. Int., 185, 108553, https://doi.org/10.1016/J.ENVINT.2024.108553, 2024.
Savadkoohi, M., Gherras, M., Favez, O., Petit, J. E., Rovira, J., Chen, G. I., Via, M., Platt, S., Aurela, M., Chazeau, B., de Brito, J. F., Riffault, V., Eleftheriadis, K., Flentje, H., Gysel-Beer, M., Hueglin, C., Rigler, M., Gregorič, A., Ivančič, M., Keernik, H., Maasikmets, M., Liakakou, E., Stavroulas, I., Luoma, K., Marchand, N., Mihalopoulos, N., Petäjä, T., Prevot, A. S. H., Daellenbach, K. R., Vodička, P., Timonen, H., Tobler, A., Vasilescu, J., Dandocsi, A., Mbengue, S., Vratolis, S., Zografou, O., Chauvigné, A., Hopke, P. K., Querol, X., Alastuey, A., and Pandolfi, M.: Addressing the advantages and limitations of using Aethalometer data to determine the optimal absorption Ångström exponents (AAEs) values for eBC source apportionment, Atmos. Environ., 349, https://doi.org/10.1016/j.atmosenv.2025.121121, 2025.
Seinfeld, J. H. and Pandis, S. N.: Atmospheric chemistry and physics, 2nd edn., John Wiley & Sons, Ltd, New Jersey, 1203 pp., https://doi.org/10.1007/978-3-662-04540-4_16, 2006.
Shen, Y., Zhi, G., Zhang, Y., Jin, W., Kong, Y., Li, Z., and Zhang, H.: An investigative review of the expanded capabilities of thermal/optical techniques for measuring carbonaceous aerosols and beyond, Environ. Pollut., 364, 125363, https://doi.org/10.1016/J.ENVPOL.2024.125363, 2025.
Song, M., Liu, P. F., Hanna, S. J., Zaveri, R. A., Potter, K., You, Y., Martin, S. T., and Bertram, A. K.: Relative humidity-dependent viscosity of secondary organic material from toluene photo-oxidation and possible implications for organic particulate matter over megacities, Atmos. Chem. Phys., 16, 8817–8830, https://doi.org/10.5194/acp-16-8817-2016, 2016.
Stein, A. F., Draxler, R. R., Rolph, G. D., Stunder, B. J. B., Cohen, M. D., and Ngan, F.: NOAA's HYSPLIT atmospheric transport and dispersion modeling system, B. Am. Meteorol. Soc., 96, 2059–2077, https://doi.org/10.1175/BAMS-D-14-00110.1, 2015.
Suchánková, L.: “Humidified single-nephelometer set-up system datasets”, Mendeley Data [data set], V1, https://doi.org/10.17632/8ds98t2f3x.1, 2025.
Suchánková, L., Crumeyrolle, S., Bourrianne, E., Prokeš, R., Holoubek, I., Ždímal, V., and Chiapello, I.: An insight into recent PM1 aerosol light scattering properties and particle number concentration variabilities at the suburban site ATOLL in Northern France, Sci. Total Environ., 959, 178190, https://doi.org/10.1016/J.SCITOTENV.2024.178190, 2025.
Tang, J., Li, J., Mo, Y., Safaei Khorram, M., Chen, Y., Tang, J., Zhang, Y., Song, J., and Zhang, G.: Light absorption and emissions inventory of humic-like substances from simulated rainforest biomass burning in Southeast Asia, Environ. Pollut., 262, https://doi.org/10.1016/J.ENVPOL.2020.114266, 2020.
Thomsen, D., Iversen, E. M., Skønager, J. T., Luo, Y., Li, L., Roldin, P., Priestley, M., Pedersen, H. B., Hallquist, M., Ehn, M., Bilde, M., and Glasius, M.: The effect of temperature and relative humidity on secondary organic aerosol formation from ozonolysis of Δ3-carene, Environ. Sci. Atmos., 4, 88–103, https://doi.org/10.1039/D3EA00128H, 2024.
Titos, G., Lyamani, H., Cazorla, A., Sorribas, M., Foyo-Moreno, I., Wiedensohler, A., and Alados-Arboledas, L.: Study of the relative humidity dependence of aerosol light-scattering in southern Spain, Tellus B, 66, 24536, https://doi.org/10.3402/tellusb.v66.24536, 2014.
Titos, G., Cazorla, A., Zieger, P., Andrews, E., Lyamani, H., Granados-Muñoz, M. J., Olmo, F. J., and Alados-Arboledas, L.: Effect of hygroscopic growth on the aerosol light-scattering coefficient: A review of measurements, techniques and error sources, Atmos. Environ., 141, 494–507, https://doi.org/10.1016/j.atmosenv.2016.07.021, 2016.
Titos, G., Burgos, M. A., Zieger, P., Alados-Arboledas, L., Baltensperger, U., Jefferson, A., Sherman, J., Weingartner, E., Henzing, B., Luoma, K., O'Dowd, C., Wiedensohler, A., and Andrews, E.: A global study of hygroscopicity-driven light-scattering enhancement in the context of other in situ aerosol optical properties, Atmos. Chem. Phys., 21, 13031–13050, https://doi.org/10.5194/acp-21-13031-2021, 2021.
Toll, V., Christensen, M., Quaas, J., and Bellouin, N.: Weak average liquid-cloud-water response to anthropogenic aerosols, Nature, 572, 51–55, https://doi.org/10.1038/s41586-019-1423-9, 2019.
Vodička, P., Schwarz, J., and Ždímal, V.: Analysis of one year's OC/EC data at a Prague suburban site with 2-h time resolution, Atmos. Environ., 77, 865–872, https://doi.org/10.1016/j.atmosenv.2013.06.013, 2013.
Vodička, P., Schwarz, J., Cusack, M., and Ždímal, V.: Detailed comparison of OC/EC aerosol at an urban and a rural Czech background site during summer and winter, Sci. Total Environ., 518–519, 424–433, https://doi.org/10.1016/j.scitotenv.2015.03.029, 2015.
Watson-Parris, D. and Smith, C. J.: Large uncertainty in future warming due to aerosol forcing, Nat. Clim. Change, 12, 1111–1113, https://doi.org/10.1038/s41558-022-01516-0, 2022.
Williams, A. I. L., Stier, P., Dagan, G., and Watson-Parris, D.: Strong control of effective radiative forcing by the spatial pattern of absorbing aerosol, Nat. Clim. Change, 12, 735–742, https://doi.org/10.1038/s41558-022-01415-4, 2022.
Wiscombie, W. J. and Grams, G. W.: Backscattered fraction in two-stream approximations, J. Atmos. Sci., 33, 2440–2451, https://doi.org/10.1175/1520-0469(1976)033<2440:tbfits>2.0.co;2, 1976.
WMO/GAW: WMO/GAW Aerosol Measurement Procedures, Guidelines and Recommendations (2nd Edition) | Climate & Clean Air Coalition, Genewa, 103 pp., ISBN 978-92-63-11177-7, 2016.
Wu, T. and Boor, B. E.: Urban aerosol size distributions: a global perspective, Atmos. Chem. Phys., 21, 8883–8914, https://doi.org/10.5194/acp-21-8883-2021, 2021.
Zhang, J., Chen, Y. S., Gryspeerdt, E., Yamaguchi, T., and Feingold, G.: Radiative forcing from the 2020 shipping fuel regulation is large but hard to detect, Commun. Earth Environ., 61, 1–11, https://doi.org/10.1038/s43247-024-01911-9, 2025.
Zieger, P., Fierz-Schmidhauser, R., Poulain, L., Müller, T., Birmili, W., Spindler, G., Wiedensohler, A., Baltensperger, U., and Weingartner, E.: Influence of water uptake on the aerosol particle light scattering coefficients of the Central European aerosol, Tellus B, 66, https://doi.org/10.3402/TELLUSB.V66.22716, 2014.
Zieger, P., Aalto, P. P., Aaltonen, V., Äijälä, M., Backman, J., Hong, J., Komppula, M., Krejci, R., Laborde, M., Lampilahti, J., de Leeuw, G., Pfüller, A., Rosati, B., Tesche, M., Tunved, P., Väänänen, R., and Petäjä, T.: Low hygroscopic scattering enhancement of boreal aerosol and the implications for a columnar optical closure study, Atmos. Chem. Phys., 15, 7247–7267, https://doi.org/10.5194/acp-15-7247-2015, 2015.
Short summary
In this work, we show how aerosol particles in city air change their ability to scatter light when exposed to humidity, which affects the climate. Using a simpler tool, we found that in Prague's suburbs, these particles showed only a small change in light scattering, likely due to carbon-rich pollution that effectively absorbs light. Our method helps to reduce certain types of measurement uncertainty and helps fill gaps in urban climate data.
In this work, we show how aerosol particles in city air change their ability to scatter light...
