Articles | Volume 26, issue 5
https://doi.org/10.5194/acp-26-3697-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/acp-26-3697-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
16 Mar 2026
Research article |
| 16 Mar 2026
| 16 Mar 2026
Cloud condensation nuclei phenomenology: predictions based on aerosol chemical and optical properties
Andalusian Institute for Earth System Research, IISTA-CEAMA, University of Granada, Junta de Andalucía, Granada, 18006, Spain
Department of Applied Physics, University of Granada, Granada 18071, Spain
Juan Andrés Casquero-Vera
Andalusian Institute for Earth System Research, IISTA-CEAMA, University of Granada, Junta de Andalucía, Granada, 18006, Spain
Department of Applied Physics, University of Granada, Granada 18071, Spain
Elisabeth Andrews
University of Colorado, CIRES, Boulder, 80309, USA
NOAA, Global Monitoring Laboratory, Boulder, 80305, USA
Andrea Casans
Andalusian Institute for Earth System Research, IISTA-CEAMA, University of Granada, Junta de Andalucía, Granada, 18006, Spain
Department of Applied Physics, University of Granada, Granada 18071, Spain
Gerardo Carrillo-Cardenas
Department Atmospheric Sciences, University of Utah, Salt Lake City, UT 84112, USA
Anna Gannet Hallar
Department Atmospheric Sciences, University of Utah, Salt Lake City, UT 84112, USA
Andalusian Institute for Earth System Research, IISTA-CEAMA, University of Granada, Junta de Andalucía, Granada, 18006, Spain
Department of Applied Physics, University of Granada, Granada 18071, Spain
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.
Erin K. Boedicker, Andre Bergeron, Gerardo Carrillo-Cardenas, Dominik Kulakowski, John Rogan, Elisabeth Andrews, and A. Gannet Hallar
Atmos. Chem. Phys., 26, 6593–6610, https://doi.org/10.5194/acp-26-6593-2026, https://doi.org/10.5194/acp-26-6593-2026, 2026
Short summary
Short summary
We present analysis of long-term aerosol measurements from two sites in Colorado. In this work, we characterize seasonal trends of aerosol optical properties for both sites and perform trend analysis to investigate changes in sources over time. We show that there is a significant increase in the influence of extreme events like smoke and dust, and explore the relationship between optical properties to identify aerosol types and temporal patterns at the two sites.
Larissa Lacher, A. Gannet Hallar, Ian B. McCubbin, Joey Bail, Karl D. Froyd, Justin Jacquot, Xiaoli Shen, Christopher Rapp, Ottmar Möhler, and Daniel Cziczo
Atmos. Chem. Phys., 26, 6703–6726, https://doi.org/10.5194/acp-26-6703-2026, https://doi.org/10.5194/acp-26-6703-2026, 2026
Short summary
Short summary
We observe a trend of increasing ice-nucleating particle (INP) concentration in spring in the Rocky Mountains, related to regional dust emissions that may intensify with climate change. Additionally, super-micrometer particles were found as the most important contributors to the INP population. This finding was partly enabled by a novel setup of the Portable Ice Nucleation Experiment (PINE), coupled with a pumped-counterflow virtual impactor allowing for direct analysis of INP properties.
Elena Bazo, Olga Ruiz-Galera, Lucas Alados-Arboledas, Alexander Böhmländer, Kristina Höhler, Najin Kim, Larissa Lacher, Ottmar Möhler, Frascisco José Olmo, German Perez Fogwill, Ana A. Piedehierro, Nsikanabasi Silas Umo, André Welti, Gloria Titos, and Alberto Cazorla
Atmos. Meas. Tech., 19, 2695–2713, https://doi.org/10.5194/amt-19-2695-2026, https://doi.org/10.5194/amt-19-2695-2026, 2026
Short summary
Short summary
We evaluated different methods to obtain the ice nucleating particle (INP) concentration from ambient filters using GRAINS (GRAnada Ice Nuclei Spectrometer), the INP spectrometer at the Andalusian ObseRvatory of the Atmosphere (AGORA). We first characterized GRAINS and compared it to other INP devices. Then, we sampled polycarbonate and quartz filters for three months and tested three different particle extraction methods, finding general good agreement but that the INP concentration is systematically higher when using quartz filters.
Ross James Herbert, Larissa Lacher, Alexander Böhmländer, Mark D. Tarn, Antione Canzi, Aidan Pantoya, Evelyn Freney, Kristina Höhler, Pia Bogert, Celine Planche, Ping Tian, Michael Adams, Sarah Barr, David Brus, Nicole Büttner, Martin Daily, Konstantinos Doulgeris, Konstantinos Eleftheridadis, Grant Forster, Romy Fösig, Dimitrios Georgakopoulos, Maria Gini, A. Gannett Hallar, Radovan Krejci, Elke Ludewig, Mauro Mazzola, Ian B. McCubbin, Tuukka Petäjä, Joseph Robinson, Franziska Vogel, Paul Zieger, Stephen R. Arnold, Kenneth S. Carslaw, Naruki Hiranuma, Ottmar Möhler, and Benjamin J. Murray
Earth Syst. Sci. Data Discuss., https://doi.org/10.5194/essd-2026-41, https://doi.org/10.5194/essd-2026-41, 2026
Revised manuscript under review for ESSD
Short summary
Short summary
Ice formation in sub-zero clouds is influenced by airborne particles called ice-nucleating particles (INPs), whose concentrations vary substantially over short time and spatial scales. To assess the role of INPs in our climate, a comprehensive and consistent global dataset is essential. Our GloPINE model-ready dataset is a major step in this direction, comprising 36,000 measurements made using a single instrument design (PINE) over 70,000 hours of operation at 20 northern hemisphere sites.
Alexander Garber, Zhaoxia Pu, and Anna Gannet Hallar
EGUsphere, https://doi.org/10.5194/egusphere-2025-6413, https://doi.org/10.5194/egusphere-2025-6413, 2026
Short summary
Short summary
This study examines how Saharan dust aerosols influenced the evolution of Tropical Storm Hermine (2022) using WRF-Chem simulations and NASA CPEX-CV observations. Results show that dust radiative effects weakened and disrupted storm organization, while reanalysis data underestimated dust concentrations. The findings highlight the importance of accurately representing aerosols to improve tropical cyclone simulations and hazard prediction.
Sami D. Harni, Lasse Johansson, Jarkko V. Niemi, Ville Silvonen, Juan Andrés Casquero-Vera, Anu Kousa, Krista Luoma, Viet Le, David Brus, Konstantinos Doulgeris, Topi Rönkkö, Hanna E. Manninen, Tuukka Petäjä, and Hilkka Timonen
Atmos. Chem. Phys., 25, 18719–18738, https://doi.org/10.5194/acp-25-18719-2025, https://doi.org/10.5194/acp-25-18719-2025, 2025
Short summary
Short summary
A three-month-long measurement campaign was conducted at Espoo, Finland, in spring 2023. The measurement campaign studied the effect of the noise barrier on pollutant concentration gradients on the side of a major highway. The studied pollutants included PM10, PM2.5, lung deposited surface area (LDSA), particle number concentration (PNC), NO2, and black carbon (BC). The noise barrier was found to be effective in reducing, especially the concentration of particulate pollutants.
Christopher N. Rapp, Gerardo Carrillo-Cardenas, Sining Niu, Yue Zhang, Fred J. Brechtel, A. Gannet Hallar, and Daniel J. Cziczo
EGUsphere, https://doi.org/10.5194/egusphere-2025-4222, https://doi.org/10.5194/egusphere-2025-4222, 2025
Short summary
Short summary
Particles within aerosol vary in both size and concentration and is termed a particle size distribution (PSD). Aerosol particles are rarely distributed such that only one similar group of particles (mode) exists. In reality, the PSD is often the sum of multiple individual modes. This work introduces an accessible tool used to decompose complex PSDs so each mode can be characterized and used to infer important properties relevant to health and climate such as formation processes and composition.
Tyler R. Elgiar, Loknath Dhar, Lynne Gratz, A. Gannet Hallar, Rainer Volkamer, and Seth N. Lyman
Atmos. Chem. Phys., 25, 16387–16399, https://doi.org/10.5194/acp-25-16387-2025, https://doi.org/10.5194/acp-25-16387-2025, 2025
Short summary
Short summary
We compare verified atmospheric mercury measurements against output from the GEOS-Chem photochemical transport model. We show the model is unable to reproduce measured atmospheric oxidized mercury concentrations, even in several cases where oxidation rates in the model are enhanced.
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
Atmos. Meas. Tech., 18, 3073–3093, https://doi.org/10.5194/amt-18-3073-2025, https://doi.org/10.5194/amt-18-3073-2025, 2025
Short summary
Short summary
We have used absorption from a photothermal interferometer and scattering measurements to evaluate the most deployed filter photometers used to measure absorption for 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 (Multiangle Absorption Photometer), usually used as a pseudo-reference instrument, had 47 % higher absorption values than our reference measurements.
Elena Bazo, Daniel Pérez-Ramírez, Antonio Valenzuela, J. Vanderlei Martins, Gloria Titos, Alberto Cazorla, Fernando Rejano, Diego Patrón, Arlett Díaz-Zurita, Francisco José García-Izquierdo, David Fuertes, Lucas Alados-Arboledas, and Francisco José Olmo
Atmos. Chem. Phys., 25, 6325–6352, https://doi.org/10.5194/acp-25-6325-2025, https://doi.org/10.5194/acp-25-6325-2025, 2025
Short summary
Short summary
This works analyzes the aerosol scattering phase function for transported Saharan dust to the city of Granada – located in southwestern Europe. We use the novel technique polar imaging nephelometry that helps to determine the phase functions using a CMOS camera. The capability of measuring with polarized light helps to infer new properties about the mixture of Saharan dust particles with those of anthropogenic origin.
Aidan D. Pantoya, Stephanie R. Simonsen, Elisabeth Andrews, Ross Burgener, Christopher J. Cox, Gijs de Boer, Bryan D. Thomas, and Naruki Hiranuma
Aerosol Research, 3, 253–270, https://doi.org/10.5194/ar-3-253-2025, https://doi.org/10.5194/ar-3-253-2025, 2025
Short summary
Short summary
We present continuous ice-nucleating particle data that were measured in the Alaskan Arctic from October 2021 to December 2023. We found a greater efficiency in the arctic immersion freezing during fall compared to those found previously at two mid-latitude sites, together with profound freezing efficiencies in spring, presumably due to arctic haze events. Our study will be useful for improving atmospheric models to simulate cloud feedback and determine their impact on the global radiative energy budget.
Paul J. DeMott, Jessica A. Mirrielees, Sarah Suda Petters, Daniel J. Cziczo, Markus D. Petters, Heinz G. Bingemer, Thomas C. J. Hill, Karl Froyd, Sarvesh Garimella, A. Gannet Hallar, Ezra J. T. Levin, Ian B. McCubbin, Anne E. Perring, Christopher N. Rapp, Thea Schiebel, Jann Schrod, Kaitlyn J. Suski, Daniel Weber, Martin J. Wolf, Maria Zawadowicz, Jake Zenker, Ottmar Möhler, and Sarah D. Brooks
Atmos. Meas. Tech., 18, 639–672, https://doi.org/10.5194/amt-18-639-2025, https://doi.org/10.5194/amt-18-639-2025, 2025
Short summary
Short summary
The Fifth International Ice Nucleation Workshop Phase 3 (FIN-03) compared the ambient atmospheric performance of ice-nucleating particle (INP) measuring systems and explored general methods for discerning atmospheric INP compositions. Mirroring laboratory results, INP concentrations agreed within 5–10 factors. Measurements of total aerosol properties and investigations of INP compositions supported a dominant role of soil and plant organic aerosol elements as INPs during the study.
Fernando Rejano, Andrea Casans, Marta Via, Juan Andrés Casquero-Vera, Sonia Castillo, Hassan Lyamani, Alberto Cazorla, Elisabeth Andrews, Daniel Pérez-Ramírez, Andrés Alastuey, Francisco Javier Gómez-Moreno, Lucas Alados-Arboledas, Francisco José Olmo, and Gloria Titos
Atmos. Chem. Phys., 24, 13865–13888, https://doi.org/10.5194/acp-24-13865-2024, https://doi.org/10.5194/acp-24-13865-2024, 2024
Short summary
Short summary
This study provides valuable insights to improve cloud condensation nuclei (CCN) estimations at a high-altitude remote site which is influenced by nearby urban pollution. Understanding the factors that affect CCN estimations is essential to improve the CCN data coverage worldwide and assess aerosol–cloud interactions on a global scale. This is crucial for improving climate models, since aerosol–cloud interactions are the most important source of uncertainty in climate projections.
Eleanor J. Derry, Tyler R. Elgiar, Taylor Y. Wilmot, Nicholas W. Hoch, Noah S. Hirshorn, Peter Weiss-Penzias, Christopher F. Lee, John C. Lin, A. Gannet Hallar, Rainer Volkamer, Seth N. Lyman, and Lynne E. Gratz
Atmos. Chem. Phys., 24, 9615–9643, https://doi.org/10.5194/acp-24-9615-2024, https://doi.org/10.5194/acp-24-9615-2024, 2024
Short summary
Short summary
Mercury (Hg) is a globally distributed neurotoxic pollutant. Atmospheric deposition is the main source of Hg in ecosystems. However, measurement biases hinder understanding of the origins and abundance of the more bioavailable oxidized form. We used an improved, calibrated measurement system to study air mass composition and transport of atmospheric Hg at a remote mountaintop site in the central US. Oxidized Hg originated upwind in the low to middle free troposphere under clean, dry conditions.
Wenyue Wang, Klemens Hocke, Leonardo Nania, Alberto Cazorla, Gloria Titos, Renaud Matthey, Lucas Alados-Arboledas, Agustín Millares, and Francisco Navas-Guzmán
Atmos. Chem. Phys., 24, 1571–1585, https://doi.org/10.5194/acp-24-1571-2024, https://doi.org/10.5194/acp-24-1571-2024, 2024
Short summary
Short summary
The south-central interior of Andalusia experiences complex precipitation patterns as a result of the semi-arid Mediterranean climate and the influence of Saharan dust. This study monitored the inter-relations between aerosols, clouds, meteorological variables, and precipitation systems using ground-based remote sensing and in situ instruments.
Juan Andrés Casquero-Vera, Daniel Pérez-Ramírez, Hassan Lyamani, Fernando Rejano, Andrea Casans, Gloria Titos, Francisco José Olmo, Lubna Dada, Simo Hakala, Tareq Hussein, Katrianne Lehtipalo, Pauli Paasonen, Antti Hyvärinen, Noemí Pérez, Xavier Querol, Sergio Rodríguez, Nikos Kalivitis, Yenny González, Mansour A. Alghamdi, Veli-Matti Kerminen, Andrés Alastuey, Tuukka Petäjä, and Lucas Alados-Arboledas
Atmos. Chem. Phys., 23, 15795–15814, https://doi.org/10.5194/acp-23-15795-2023, https://doi.org/10.5194/acp-23-15795-2023, 2023
Short summary
Short summary
Here we present the first study of the effect of mineral dust on the inhibition/promotion of new particle formation (NPF) events in different dust-influenced areas. Unexpectedly, we show that the occurrence of NPF events is highly frequent during mineral dust outbreaks, occurring even during extreme dust outbreaks. We also show that the occurrence of NPF events during mineral dust outbreaks significantly affects the potential cloud condensation nuclei budget.
Alessandro Bigi, Giorgio Veratti, Elisabeth Andrews, Martine Collaud Coen, Lorenzo Guerrieri, Vera Bernardoni, Dario Massabò, Luca Ferrero, Sergio Teggi, and Grazia Ghermandi
Atmos. Chem. Phys., 23, 14841–14869, https://doi.org/10.5194/acp-23-14841-2023, https://doi.org/10.5194/acp-23-14841-2023, 2023
Short summary
Short summary
Atmospheric particles include compounds that play a key role in the greenhouse effect and air toxicity. Concurrent observations of these compounds by multiple instruments are presented, following deployment within an urban environment in the Po Valley, one of Europe's pollution hotspots. The study compares these data, highlighting the impact of ground emissions, mainly vehicular traffic and biomass burning, on the absorption of sun radiation and, ultimately, on climate change and air quality.
Erin K. Boedicker, Elisabeth Andrews, Patrick J. Sheridan, and Patricia K. Quinn
Atmos. Chem. Phys., 23, 9525–9547, https://doi.org/10.5194/acp-23-9525-2023, https://doi.org/10.5194/acp-23-9525-2023, 2023
Short summary
Short summary
We present 15 years of measurements from a marine site on the northern California coast and characterize the seasonal trends of aerosol ion composition and optical properties at the site. We investigate the relationship between the chemical and optical properties and show that they both support similar seasonal variations in aerosol sources at the site. Additionally, we show through comparisons to other marine aerosol observations that the site is representative of a clean marine environment.
Daniel A. Jaffe, Colleen Miller, Katie Thompson, Brandon Finley, Manna Nelson, James Ouimette, and Elisabeth Andrews
Atmos. Meas. Tech., 16, 1311–1322, https://doi.org/10.5194/amt-16-1311-2023, https://doi.org/10.5194/amt-16-1311-2023, 2023
Short summary
Short summary
PurpleAir sensors (PASs) are low-cost tools to measure fine particulate matter (PM) concentrations. However, the raw PAS data have significant biases, so the sensors must be corrected. We analyzed data from numerous sites and found that the standard correction to the PAS Purple Air data is accurate in urban pollution events and smoke events but leads to a 6-fold underestimate in the PM2.5 concentrations in dust events. We propose a new correction algorithm to address this problem.
Noah S. Hirshorn, Lauren M. Zuromski, Christopher Rapp, Ian McCubbin, Gerardo Carrillo-Cardenas, Fangqun Yu, and A. Gannet Hallar
Atmos. Chem. Phys., 22, 15909–15924, https://doi.org/10.5194/acp-22-15909-2022, https://doi.org/10.5194/acp-22-15909-2022, 2022
Short summary
Short summary
New particle formation (NPF) is a source of atmospheric aerosol number concentration that can impact climate by growing to larger sizes and under proper conditions form cloud condensation nuclei (CCN). Using novel methods, we find that at Storm Peak Laboratory, a remote, mountaintop site in Colorado, NPF is observed to enhance CCN concentrations in the spring by a factor of 1.54 and in the winter by a factor of 1.36 which can occur on a regional scale having important climate implications.
Anna L. Hodshire, Ezra J. T. Levin, A. Gannet Hallar, Christopher N. Rapp, Dan R. Gilchrist, Ian McCubbin, and Gavin R. McMeeking
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2022-216, https://doi.org/10.5194/amt-2022-216, 2022
Publication in AMT not foreseen
Short summary
Short summary
The new Continuous Flow Diffusion Chamber-Ice Activation Spectrometer collected 4 months of ice nucleating particle (INP) measurements at a 5-minute resolution at the mountainside Storm Peak Laboratory. Most long-term INP measurements are at a time resolution of a day or longer: our instrument is a promising advance towards high-resolution long-term INP measurements. We observe higher peak INP concentrations than previous mountain studies, possibly due to the higher time resolution of our data.
Libby Koolik, Michael Roesch, Carmen Dameto de Espana, Christopher Nathan Rapp, Lesly J. Franco Deloya, Chuanyang Shen, A. Gannet Hallar, Ian B. McCubbin, and Daniel J. Cziczo
Atmos. Meas. Tech., 15, 3213–3222, https://doi.org/10.5194/amt-15-3213-2022, https://doi.org/10.5194/amt-15-3213-2022, 2022
Short summary
Short summary
A new inlet for studying the small particles, droplets, and ice crystals that constitute mixed-phase clouds has been constructed and is described here. This new inlet was tested in the laboratory. We present the performance of the new inlet to demonstrate its capability of separating ice, droplets, and small particles.
Aki Virkkula, Henrik Grythe, John Backman, Tuukka Petäjä, Maurizio Busetto, Christian Lanconelli, Angelo Lupi, Silvia Becagli, Rita Traversi, Mirko Severi, Vito Vitale, Patrick Sheridan, and Elisabeth Andrews
Atmos. Chem. Phys., 22, 5033–5069, https://doi.org/10.5194/acp-22-5033-2022, https://doi.org/10.5194/acp-22-5033-2022, 2022
Short summary
Short summary
Optical properties of surface aerosols at Dome C, Antarctica, in 2007–2013 and their potential source areas are presented. The equivalent black carbon (eBC) mass concentrations were compared with eBC measured at three other Antarctic sites: the South Pole (SPO) and two coastal sites, Neumayer and Syowa. Transport analysis suggests that South American BC emissions are the largest contributor to eBC at Dome C.
Julia Schmale, Sangeeta Sharma, Stefano Decesari, Jakob Pernov, Andreas Massling, Hans-Christen Hansson, Knut von Salzen, Henrik Skov, Elisabeth Andrews, Patricia K. Quinn, Lucia M. Upchurch, Konstantinos Eleftheriadis, Rita Traversi, Stefania Gilardoni, Mauro Mazzola, James Laing, and Philip Hopke
Atmos. Chem. Phys., 22, 3067–3096, https://doi.org/10.5194/acp-22-3067-2022, https://doi.org/10.5194/acp-22-3067-2022, 2022
Short summary
Short summary
Long-term data sets of Arctic aerosol properties from 10 stations across the Arctic provide evidence that anthropogenic influence on the Arctic atmospheric chemical composition has declined in winter, a season which is typically dominated by mid-latitude emissions. The number of significant trends in summer is smaller than in winter, and overall the pattern is ambiguous with some significant positive and negative trends. This reflects the mixed influence of natural and anthropogenic emissions.
James R. Ouimette, William C. Malm, Bret A. Schichtel, Patrick J. Sheridan, Elisabeth Andrews, John A. Ogren, and W. Patrick Arnott
Atmos. Meas. Tech., 15, 655–676, https://doi.org/10.5194/amt-15-655-2022, https://doi.org/10.5194/amt-15-655-2022, 2022
Short summary
Short summary
We show that the low-cost PurpleAir sensor can be characterized as a cell-reciprocal nephelometer. At two very different locations (Mauna Loa Observatory in Hawaii and the Table Mountain rural site in Colorado), the PurpleAir measurements are highly correlated with the submicrometer aerosol scattering coefficient measured by a research-grade integrating nephelometer. These results imply that, with care, PurpleAir data may be used to evaluate climate and air quality models.
Anna L. Hodshire, Ezra J. T. Levin, A. Gannet Hallar, Christopher N. Rapp, Dan R. Gilchrist, Ian McCubbin, and Gavin R. McMeeking
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2022-29, https://doi.org/10.5194/acp-2022-29, 2022
Preprint withdrawn
Short summary
Short summary
The new Continuous Flow Diffusion Chamber-Ice Activation Spectrometer collected 4 months of ice nucleating particle (INP) measurements at a 5-minute resolution at the mountainside Storm Peak Laboratory. Most long-term INP measurements are at a time resolution of a day or longer: our instrument is a promising advance towards high-resolution long-term INP measurements. We observe higher peak INP concentrations than previous mountain studies, possibly due to the higher time resolution of our data.
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.
Sho Ohata, Tatsuhiro Mori, Yutaka Kondo, Sangeeta Sharma, Antti Hyvärinen, Elisabeth Andrews, Peter Tunved, Eija Asmi, John Backman, Henri Servomaa, Daniel Veber, Konstantinos Eleftheriadis, Stergios Vratolis, Radovan Krejci, Paul Zieger, Makoto Koike, Yugo Kanaya, Atsushi Yoshida, Nobuhiro Moteki, Yongjing Zhao, Yutaka Tobo, Junji Matsushita, and Naga Oshima
Atmos. Meas. Tech., 14, 6723–6748, https://doi.org/10.5194/amt-14-6723-2021, https://doi.org/10.5194/amt-14-6723-2021, 2021
Short summary
Short summary
Reliable values of mass absorption cross sections (MACs) of black carbon (BC) are required to determine mass concentrations of BC at Arctic sites using different types of filter-based absorption photometers. We successfully estimated MAC values for these instruments through comparison with independent measurements of BC by a continuous soot monitoring system called COSMOS. These MAC values are consistent with each other and applicable to study spatial and temporal variation in BC in the Arctic.
Gloria Titos, María A. Burgos, Paul Zieger, Lucas Alados-Arboledas, Urs Baltensperger, Anne Jefferson, James Sherman, Ernest Weingartner, Bas Henzing, Krista Luoma, Colin O'Dowd, Alfred Wiedensohler, and Elisabeth Andrews
Atmos. Chem. Phys., 21, 13031–13050, https://doi.org/10.5194/acp-21-13031-2021, https://doi.org/10.5194/acp-21-13031-2021, 2021
Short summary
Short summary
This paper investigates the impact of water uptake on aerosol optical properties, in particular the aerosol light-scattering coefficient. Although in situ measurements are performed at low relative humidity (typically at
RH < 40 %), to address the climatic impact of aerosol particles it is necessary to take into account the effect that water uptake may have on the aerosol optical properties.
Daniel Pérez-Ramírez, David N. Whiteman, Igor Veselovskii, Richard Ferrare, Gloria Titos, María José Granados-Muñoz, Guadalupe Sánchez-Hernández, and Francisco Navas-Guzmán
Atmos. Chem. Phys., 21, 12021–12048, https://doi.org/10.5194/acp-21-12021-2021, https://doi.org/10.5194/acp-21-12021-2021, 2021
Short summary
Short summary
This paper shows how aerosol hygroscopicity enhances the vertical profile of aerosol backscattering and extinction. The study is possible thanks to the large set of remote sensing instruments and focuses on the the Baltimore–Washington DC metropolitan area during hot and humid summer days with very relevant anthropogenic emission aerosol sources. The results illustrate how the combination of aerosol emissions and meteorological conditions ultimately alters the aerosol radiative forcing.
Cited articles
Aklilu, Y. A., Mozurkewich, M., Prenni, A. J., Kreidenweis, S. M., Alfarra, M. R., Allan, J. D., Anlauf, K., Brook, J., Leaitch, W. R., Sharma, S., Boudries, H., and Worsnop, D. R.: Hygroscopicity of particles at two rural, urban influenced sites during Pacific 2001: Comparison with estimates of water uptake from particle composition, Atmos. Environ., 40, 2650–2661, https://doi.org/10.1016/j.atmosenv.2005.11.063, 2006. a
Almeida, G. P., Brito, J., Morales, C. A., Andrade, M. F., and Artaxo, P.: Measured and modelled cloud condensation nuclei (CCN) concentration in São Paulo, Brazil: the importance of aerosol size-resolved chemical composition on CCN concentration prediction, Atmos. Chem. Phys., 14, 7559–7572, https://doi.org/10.5194/acp-14-7559-2014, 2014. a
Anderson, N., Strader, R., and Davidson, C.: Airborne reduced nitrogen: ammonia emissions from agriculture and other sources, Environ. Int., 29, 277–286, https://doi.org/10.1016/S0160-4120(02)00186-1, 2003. a
Andreae, M. O.: Correlation between cloud condensation nuclei concentration and aerosol optical thickness in remote and polluted regions, Atmos. Chem. Phys., 9, 543–556, https://doi.org/10.5194/acp-9-543-2009, 2009. a
Andrews, E., Zabala, I., Carrillo-Cardenas, G., Titos, G., Casquero-Vera, J. A., and Hallar, A. G.: Harmonized aerosol size distribution, cloud condensation nuclei, chemistry and optical properties at 10 sites, Sci. Data, 12, https://doi.org/10.1038/s41597-025-04931-y, 2025a. a, b, c, d, e, f, g, h, i, j, k, l, m, n, o, p
Andrews, E., Zabala, I., Carrillo-Cardenas, G., Titos, G., Casquero-Vera, J. A., and Hallar, A. G.: Harmonized aerosol size distribution, cloud condensation nuclei, chemistry and optical properties at 12 sites, figshare [data set], https://doi.org/10.6084/m9.figshare.27913806.v1, 2025b. a, b, c, d, e
Ansmann, A., Ohneiser, K., Engelmann, R., Radenz, M., Griesche, H., Hofer, J., Althausen, D., Creamean, J. M., Boyer, M. C., Knopf, D. A., Dahlke, S., Maturilli, M., Gebauer, H., Bühl, J., Jimenez, C., Seifert, P., and Wandinger, U.: Annual cycle of aerosol properties over the central Arctic during MOSAiC 2019–2020 – light-extinction, CCN, and INP levels from the boundary layer to the tropopause, Atmos. Chem. Phys., 23, 12821–12849, https://doi.org/10.5194/acp-23-12821-2023, 2023. a
Baltensperger, U., Gäggeler, H. W., Jost, D. T., Lugauer, M., Schwikowski, M., Weingartner, E., and Seibert, P.: Aerosol climatology at the high-alpine site Jungfraujoch, Switzerland, J. Geophys. Res.-Atmos., 102, 19707–19715, https://doi.org/10.1029/97JD00928, 1997. a
Barbaro, E., Feltracco, M., De Blasi, F., Turetta, C., Radaelli, M., Cairns, W., Cozzi, G., Mazzi, G., Casula, M., Gabrieli, J., Barbante, C., and Gambaro, A.: Chemical characterization of atmospheric aerosols at a high-altitude mountain site: a study of source apportionment, Atmos. Chem. Phys., 24, 2821–2835, https://doi.org/10.5194/acp-24-2821-2024, 2024. a
Barrie, L.: Arctic air pollution: An overview of current knowledge, Atmos. Environ., 20, 643–663, https://doi.org/10.1016/0004-6981(86)90180-0, 1986. a
Beck, I., Angot, H., Baccarini, A., Dada, L., Quéléver, L., Jokinen, T., Laurila, T., Lampimäki, M., Bukowiecki, N., Boyer, M., Gong, X., Gysel-Beer, M., Petäjä, T., Wang, J., and Schmale, J.: Automated identification of local contamination in remote atmospheric composition time series, Atmos. Meas. Tech., 15, 4195–4224, https://doi.org/10.5194/amt-15-4195-2022, 2022. a
Bergstrom, R. W., Pilewskie, P., Russell, P. B., Redemann, J., Bond, T. C., Quinn, P. K., and Sierau, B.: Spectral absorption properties of atmospheric aerosols, Atmos. Chem. Phys., 7, 5937–5943, https://doi.org/10.5194/acp-7-5937-2007, 2007. a
Bond, T. C., Anderson, T. L., and Campbell, D.: Calibration and Intercomparison of Filter-Based Measurements of Visible Light Absorption by Aerosols, Aerosol Sci. Technol., 30, 582–600, https://doi.org/10.1080/027868299304435, 1999. a
Bougiatioti, A., Fountoukis, C., Kalivitis, N., Pandis, S. N., Nenes, A., and Mihalopoulos, N.: Cloud condensation nuclei measurements in the marine boundary layer of the Eastern Mediterranean: CCN closure and droplet growth kinetics, Atmos. Chem. Phys., 9, 7053–7066, https://doi.org/10.5194/acp-9-7053-2009, 2009. a, b
Bougiatioti, A., Nenes, A., Fountoukis, C., Kalivitis, N., Pandis, S. N., and Mihalopoulos, N.: Size-resolved CCN distributions and activation kinetics of aged continental and marine aerosol, Atmos. Chem. Phys., 11, 8791–8808, https://doi.org/10.5194/acp-11-8791-2011, 2011. a
Boyer, M., Aliaga, D., Pernov, J. B., Angot, H., Quéléver, L. L. J., Dada, L., Heutte, B., Dall'Osto, M., Beddows, D. C. S., Brasseur, Z., Beck, I., Bucci, S., Duetsch, M., Stohl, A., Laurila, T., Asmi, E., Massling, A., Thomas, D. C., Nøjgaard, J. K., Chan, T., Sharma, S., Tunved, P., Krejci, R., Hansson, H. C., Bianchi, F., Lehtipalo, K., Wiedensohler, A., Weinhold, K., Kulmala, M., Petäjä, T., Sipilä, M., Schmale, J., and Jokinen, T.: A full year of aerosol size distribution data from the central Arctic under an extreme positive Arctic Oscillation: insights from the Multidisciplinary drifting Observatory for the Study of Arctic Climate (MOSAiC) expedition, Atmos. Chem. Phys., 23, 389–415, https://doi.org/10.5194/acp-23-389-2023, 2023. a
Breiman, L.: Random Forests, Mach. Learn., 45, 5–32, https://doi.org/10.1023/A:1010933404324, 2001. a, b, c, d
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, 157, https://doi.org/10.1038/s41597-019-0158-7, 2019. a
Cai, M., Huang, S., Liang, B., Sun, Q., Liu, L., Yuan, B., Shao, M., Hu, W., Chen, W., Song, Q., Li, W., Peng, Y., Wang, Z., Chen, D., Tan, H., Xu, H., Li, F., Deng, X., Deng, T., Sun, J., and Zhao, J.: Measurement report: Distinct size dependence and diurnal variation in organic aerosol hygroscopicity, volatility, and cloud condensation nuclei activity at a rural site in the Pearl River Delta (PRD) region, China, Atmos. Chem. Phys., 22, 8117–8136, https://doi.org/10.5194/acp-22-8117-2022, 2022. a
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. a
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. a
Che, H., Zhang, L., Segal-Rozenhaimer, M., Dang, C., Zuidema, P., and Sedlacek III, A. J.: Aerosol hygroscopicity over the South-East Atlantic Ocean during the biomass burning season – Part 2: Influence of sea salt and burning conditions on CCN hygroscopicity, Atmos. Chem. Phys., 25, 10987–11002, https://doi.org/10.5194/acp-25-10987-2025, 2025. a
Cohard, J., Pinty, J., and Bedos, C.: Extending Twomey's analytical estimate of nucleated cloud droplet concentrations from CCN spectra, J. Atmos. Sci., 55, 3348–3357, https://doi.org/10.1175/1520-0469(1998)055<3348:ETSAEO>2.0.CO;2, 1998. a
Collaud Coen, M., Weingartner, E., Nyeki, S., Cozic, J., Henning, S., Verheggen, B., Gehrig, R., and Baltensperger, U.: Long-term trend analysis of aerosol variables at the high-alpine site Jungfraujoch, J. Geophys. Res.-Atmos., 112, https://doi.org/10.1029/2006JD007995, 2007. a, b, c
Collaud Coen, M., Weingartner, E., Furger, M., Nyeki, S., Prévôt, A. S. H., Steinbacher, M., and Baltensperger, U.: Aerosol climatology and planetary boundary influence at the Jungfraujoch analyzed by synoptic weather types, Atmos. Chem. Phys., 11, 5931–5944, https://doi.org/10.5194/acp-11-5931-2011, 2011. a
Collaud Coen, M., Andrews, E., Aliaga, D., Andrade, M., Angelov, H., Bukowiecki, N., Ealo, M., Fialho, P., Flentje, H., Hallar, A. G., Hooda, R., Kalapov, I., Krejci, R., Lin, N.-H., Marinoni, A., Ming, J., Nguyen, N. A., Pandolfi, M., Pont, V., Ries, L., Rodríguez, S., Schauer, G., Sellegri, K., Sharma, S., Sun, J., Tunved, P., Velasquez, P., and Ruffieux, D.: Identification of topographic features influencing aerosol observations at high altitude stations, Atmos. Chem. Phys., 18, 12289–12313, https://doi.org/10.5194/acp-18-12289-2018, 2018. a
Cubison, M. J., Ervens, B., Feingold, G., Docherty, K. S., Ulbrich, I. M., Shields, L., Prather, K., Hering, S., and Jimenez, J. L.: The influence of chemical composition and mixing state of Los Angeles urban aerosol on CCN number and cloud properties, Atmos. Chem. Phys., 8, 5649–5667, https://doi.org/10.5194/acp-8-5649-2008, 2008. a
Cutler, A., Cutler, D. R., and Stevens, J. R.: Random Forests, in: Ensemble Machine Learning, edited by: Zhang, C. and Ma, Y., pp. 157–175, Springer, New York, https://doi.org/10.1007/978-1-4419-9326-7_5, 2012. a
Dada, L., Angot, H., Beck, I., Baccarini, A., Quéléver, L., Boyer, M., Laurila, T., Brasseur, Z., Jozef, G., de Boer, G., Shupe, M., Henning, S., Bucci, S., Dütsch, M., Stohl, A., Petäjä, T., Daellenbach, K., Jokinen, T., and Schmale, J.: A central arctic extreme aerosol event triggered by a warm air-mass intrusion, Nat. Commun., 13, https://doi.org/10.1038/s41467-022-32872-2, 2022. a
Deng, Y., Kagami, S., Ogawa, S., Kawana, K., Nakayama, T., Kubodera, R., Adachi, K., Hussein, T., Miyazaki, Y., and Mochida, M.: Hygroscopicity of Organic Aerosols and Their Contributions to CCN Concentrations Over a Midlatitude Forest in Japan, J. Geophys. Res.-Atmos., 123, https://doi.org/10.1029/2017JD027292, 2018. a
Deshmukh, S., Poulain, L., Wehner, B., Henning, S., Petit, J.-E., Fombelle, P., Favez, O., Herrmann, H., and Pöhlker, M.: External particle mixing influences hygroscopicity in a sub-urban area, Atmos. Chem. Phys., 25, 741–758, https://doi.org/10.5194/acp-25-741-2025, 2025. a
Duan, J., Chen, Y., Zhang, X., Wang, W., Zhong, S., Li, J., Lu, G., Fang, C., Guo, L., and Fu, P.: Influence of aerosol physicochemical properties on CCN activation during the Asian winter monsoon at the summit of Mt. Lu, China, Atmos. Environ., 296, https://doi.org/10.1016/j.atmosenv.2023.119592, 2023. a
Dusek, U., Frank, G. P., Curtius, J., Drewnick, F., Schneider, J., Kürten, A., Rose, D., Andreae, M. O., Borrmann, S., and Pöschl, U.: Enhanced organic mass fraction and decreased hygroscopicity of cloudcondensation nuclei (CCN) during new particle formation events, Geophys. Res. Lett., 37, https://doi.org/10.1029/2009GL040930, 2010. a
Ervens, B., Cubison, M., Andrews, E., Feingold, G., Ogren, J., Jimenez, J., DeCarlo, P., and Nenes, A.: Prediction of cloud condensation nucleus number concentration using measurements of aerosol size distributions and composition and light scattering enhancement due to humidity, J. Geophys. Res.-Atmos., 112, https://doi.org/10.1029/2006JD007426, 2007. a
Fanourgakis, G. S., Kanakidou, M., Nenes, A., Bauer, S. E., Bergman, T., Carslaw, K. S., Grini, A., Hamilton, D. S., Johnson, J. S., Karydis, V. A., Kirkevåg, A., Kodros, J. K., Lohmann, U., Luo, G., Makkonen, R., Matsui, H., Neubauer, D., Pierce, J. R., Schmale, J., Stier, P., Tsigaridis, K., van Noije, T., Wang, H., Watson-Parris, D., Westervelt, D. M., Yang, Y., Yoshioka, M., Daskalakis, N., Decesari, S., Gysel-Beer, M., Kalivitis, N., Liu, X., Mahowald, N. M., Myriokefalitakis, S., Schrödner, R., Sfakianaki, M., Tsimpidi, A. P., Wu, M., and Yu, F.: Evaluation of global simulations of aerosol particle and cloud condensation nuclei number, with implications for cloud droplet formation, Atmos. Chem. Phys., 19, 8591–8617, https://doi.org/10.5194/acp-19-8591-2019, 2019. a, b
Fast, J. D., Varble, A. C., Mei, F., Pekour, M., Tomlinson, J., Zelenyuk, A., Sedlacek III, A. J., Zawadowicz, M., and Emmons, L.: Large spatiotemporal variability in aerosol properties over central Argentina during the CACTI field campaign, Atmos. Chem. Phys., 24, 13477–13502, https://doi.org/10.5194/acp-24-13477-2024, 2024. a, b, c
Fröhlich, R., Cubison, M. J., Slowik, J. G., Bukowiecki, N., Canonaco, F., Croteau, P. L., Gysel, M., Henne, S., Herrmann, E., Jayne, J. T., Steinbacher, M., Worsnop, D. R., Baltensperger, U., and Prévôt, A. S. H.: Fourteen months of on-line measurements of the non-refractory submicron aerosol at the Jungfraujoch (3580 m a.s.l.) – chemical composition, origins and organic aerosol sources, Atmos. Chem. Phys., 15, 11373–11398, https://doi.org/10.5194/acp-15-11373-2015, 2015. a
Gallo, F., Uin, J., Springston, S., Wang, J., Zheng, G., Kuang, C., Wood, R., Azevedo, E. B., McComiskey, A., Mei, F., Theisen, A., Kyrouac, J., and Aiken, A. C.: Identifying a regional aerosol baseline in the eastern North Atlantic using collocated measurements and a mathematical algorithm to mask high-submicron-number-concentration aerosol events, Atmos. Chem. Phys., 20, 7553–7573, https://doi.org/10.5194/acp-20-7553-2020, 2020. a
Gallo, F., Uin, J., Sanchez, K. J., Moore, R. H., Wang, J., Wood, R., Mei, F., Flynn, C., Springston, S., Azevedo, E. B., Kuang, C., and Aiken, A. C.: Long-range transported continental aerosol in the eastern North Atlantic: three multiday event regimes influence cloud condensation nuclei, Atmos. Chem. Phys., 23, 4221–4246, https://doi.org/10.5194/acp-23-4221-2023, 2023. a
Ghan, S. J., Rissman, T. A., Elleman, R., Ferrare, R. A., Turner, D., Flynn, C., Wang, J., Ogren, J., Hudson, J., Jonsson, H. H., VanReken, T., Flagan, R. C., and Seinfeld, J. H.: Use of in situ cloud condensation nuclei, extinction, and aerosol size distribution measurements to test a method for retrieving cloud condensation nuclei profiles from surface measurements, J. Geophys. Res.-Atmos., 111, https://doi.org/10.1029/2004jd005752, 2006. a, b
Gibson, L. D., Levin, E. J. T., Emerson, E., Good, N., Hodshire, A., McMeeking, G., Patterson, K., Rainwater, B., Ramin, T., and Swanson, B.: Measurement report: An investigation of the spatiotemporal variability in aerosols in the mountainous terrain of the upper Colorado River basin using SAIL-Net, Atmos. Chem. Phys., 25, 2745–2762, https://doi.org/10.5194/acp-25-2745-2025, 2025. a, b, c
Grange, S. K., Carslaw, D. C., Lewis, A. C., Boleti, E., and Hueglin, C.: Random forest meteorological normalisation models for Swiss PM10 trend analysis, Atmos. Chem. Phys., 18, 6223–6239, https://doi.org/10.5194/acp-18-6223-2018, 2018. a
Gregorutti, B., Bertrand, M., and Saint-Pierre, P.: Correlation and variable importance in random forests, Stat. Comput., 27, 659–678, https://doi.org/10.1007/s11222-016-9646-1, 2017. a
Gunthe, S. S., King, S. M., Rose, D., Chen, Q., Roldin, P., Farmer, D. K., Jimenez, J. L., Artaxo, P., Andreae, M. O., Martin, S. T., and Pöschl, U.: Cloud condensation nuclei in pristine tropical rainforest air of Amazonia: size-resolved measurements and modeling of atmospheric aerosol composition and CCN activity, Atmos. Chem. Phys., 9, 7551–7575, https://doi.org/10.5194/acp-9-7551-2009, 2009. a
Gysel, M., Crosier, J., Topping, D. O., Whitehead, J. D., Bower, K. N., Cubison, M. J., Williams, P. I., Flynn, M. J., McFiggans, G. B., and Coe, H.: Closure study between chemical composition and hygroscopic growth of aerosol particles during TORCH2, Atmos. Chem. Phys., 7, 6131–6144, https://doi.org/10.5194/acp-7-6131-2007, 2007. a, b
Hallar, A. G., Chirokova, G., McCubbin, I., Painter, T. H., Wiedinmyer, C., and Dodson, C.: Atmospheric bioaerosols transported via dust storms in the western United States, Geophys. Res. Lett., 38, https://doi.org/10.1029/2011GL048166, 2011. a
Hallar, A. G., Petersen, R., Andrews, E., Michalsky, J., McCubbin, I. B., and Ogren, J. A.: Contributions of dust and biomass burning to aerosols at a Colorado mountain-top site, Atmos. Chem. Phys., 15, 13665–13679, https://doi.org/10.5194/acp-15-13665-2015, 2015. a
Hallar, A. G., McCubbin, I. B., Borys, R., Lowenthal, D. H., Wetzel, M., Hindman, E., Brooks, S. D., Steenburgh, W. J., Gratz, L., Hoch, S., Stephens, B., Horel, J. D., Molotch, N. P., Mace, G. G., Bailey, A., Pettersen, C., Andrews, E., Cziczo, D. J., and Garcia, M.: Storm Peak Laboratory: A Research and Training Facility for the Atmospheric Sciences, B. Am. Meteorol. Soc., 106, E1130–E1148, https://doi.org/10.1175/BAMS-D-24-0043.1, 2025. a
Hirshorn, N. S., Zuromski, L. M., Rapp, C., McCubbin, I., Carrillo-Cardenas, G., Yu, F., and Hallar, A. G.: Seasonal significance of new particle formation impacts on cloud condensation nuclei at a mountaintop location, Atmos. Chem. Phys., 22, 15909–15924, https://doi.org/10.5194/acp-22-15909-2022, 2022. a
IPCC: Intergovernmental Panel on Climate Change: Climate Change 2021: The Physical Science Basis, Cambridge University Press, https://doi.org/10.1017/9781009157896, 2021. a
Jaegle, L., Steinberger, A. L., Martin, R. V., and Chance, K.: Global partitioning of NOx sources using satellite observations: Relative roles of fossil fuel combustion, biomass burning and soil emissions, Faraday Discuss., 130, 407–423, https://doi.org/10.1039/B502128F, 2005. a
Jayachandran, V. N., Suresh Babu, S. N., Vaishya, A., Gogoi, M. M., Nair, V. S., Satheesh, S. K., and Krishna Moorthy, K.: Altitude profiles of cloud condensation nuclei characteristics across the Indo-Gangetic Plain prior to the onset of the Indian summer monsoon, Atmos. Chem. Phys., 20, 561–576, https://doi.org/10.5194/acp-20-561-2020, 2020. a
Jimenez, J. L., Canagaratna, M. R., Donahue, N. M., Prevot, A. S., Zhang, Q., Kroll, J. H., DeCarlo, P. F., Allan, J. D., Coe, H., Ng, N. L., Aiken, A. C., Docherty, K. S., Ulbrich, I. M., Grieshop, A. P., Robinson, A. L., Duplissy, J., Smith, J. D., Wilson, K. R., Lanz, V. A., Hueglin, C., Sun, Y. L., Tian, J., Laaksonen, A., Raatikainen, T., Rautiainen, J., Vaattovaara, P., Ehn, M., Kulmala, M., Tomlinson, J. M., Collins, D. R., Cubison, M. J., Dunlea, E. J., Huffman, J. A., Onasch, T. B., Alfarra, M. R., Williams, P. I., Bower, K., Kondo, Y., Schneider, J., Drewnick, F., Borrmann, S., Weimer, S., Demerjian, K., Salcedo, D., Cottrell, L., Griffin, R., Takami, A., Miyoshi, T., Hatakeyama, S., Shimono, A., Sun, J. Y., Zhang, Y. M., Dzepina, K., Kimmel, J. R., Sueper, D., Jayne, J. T., Herndon, S. C., Trimborn, A. M., Williams, L. R., Wood, E. C., Middlebrook, A. M., Kolb, C. E., Baltensperger, U., and Worsnop, D. R.: Evolution of organic aerosols in the atmosphere, Science, 11, 1525–1529, https://doi.org/10.1126/science.1180353, 2009. a
Jurányi, Z., Gysel, M., Weingartner, E., DeCarlo, P. F., Kammermann, L., and Baltensperger, U.: Measured and modelled cloud condensation nuclei number concentration at the high alpine site Jungfraujoch, Atmos. Chem. Phys., 10, 7891–7906, https://doi.org/10.5194/acp-10-7891-2010, 2010. a
Jurányi, Z., Gysel, M., Weingartner, E., Bukowiecki, N., Kammermann, L., and Baltensperger, U.: A 17 month climatology of the cloud condensation nuclei number concentration at the high alpine site Jungfraujoch, J. Geophys. Res.-Atmos., 10, 7891–7906, https://doi.org/10.1029/2010JD015199, 2011. a, b, c, d, e
Kang, M., Fu, P., Kawamura, K., Yang, F., Zhang, H., Zang, Z., Ren, H., Ren, L., Zhao, Y., Sun, Y., and Wang, Z.: Characterization of biogenic primary and secondary organic aerosols in the marine atmosphere over the East China Sea, Atmos. Chem. Phys., 18, 13947–13967, https://doi.org/10.5194/acp-18-13947-2018, 2018. a
Kirchstetter, T., Novakov, T., and Hobbs, P.: Evidence that the spectral dependence of light absorption by aerosols is affected by organic carbon, J. Geophys. Res.-Atmos., 109, https://doi.org/10.1029/2004JD004999, 2004. a, b
Kulkarni, G., Mei, F., Shilling, J. E., Wang, J., Pinto Reveggino, R., Flynn, C., Zelenyuk, A., and Fast, J.: Cloud Condensation Nuclei Closure Study Using Airborne Measurements Over the Southern Great Plains, J. Geophys. Res.-Atmos., 128, https://doi.org/10.1029/2022JD037964, 2023. a
Laj, P., Bigi, A., Rose, C., Andrews, E., Lund Myhre, C., Collaud Coen, M., Lin, Y., Wiedensohler, A., Schulz, M., Ogren, J. A., Fiebig, M., Gliß, J., Mortier, A., Pandolfi, M., Petäja, T., Kim, S.-W., Aas, W., Putaud, J.-P., Mayol-Bracero, O., Keywood, M., Labrador, L., Aalto, P., Ahlberg, E., Alados Arboledas, L., Alastuey, A., Andrade, M., Artíñano, B., Ausmeel, S., Arsov, T., Asmi, E., Backman, J., Baltensperger, U., Bastian, S., Bath, O., Beukes, J. P., Brem, B. T., Bukowiecki, N., Conil, S., Couret, C., Day, D., Dayantolis, W., Degorska, A., Eleftheriadis, K., Fetfatzis, P., Favez, O., Flentje, H., Gini, M. I., Gregorič, A., Gysel-Beer, M., Hallar, A. G., Hand, J., Hoffer, A., Hueglin, C., Hooda, R. K., Hyvärinen, A., Kalapov, I., Kalivitis, N., Kasper-Giebl, A., Kim, J. E., Kouvarakis, G., Kranjc, I., Krejci, R., Kulmala, M., Labuschagne, C., Lee, H.-J., Lihavainen, H., Lin, N.-H., Löschau, G., Luoma, K., Marinoni, A., Martins Dos Santos, S., Meinhardt, F., Merkel, M., Metzger, J.-M., Mihalopoulos, N., Nguyen, N. A., Ondracek, J., Pérez, N., Perrone, M. R., Petit, J.-E., Picard, D., Pichon, J.-M., Pont, V., Prats, N., Prenni, A., Reisen, F., Romano, S., Sellegri, K., Sharma, S., Schauer, G., Sheridan, P., Sherman, J. P., Schütze, M., Schwerin, A., Sohmer, R., Sorribas, M., Steinbacher, M., Sun, J., Titos, G., Toczko, B., Tuch, T., Tulet, P., Tunved, P., Vakkari, V., Velarde, F., Velasquez, P., Villani, P., Vratolis, S., Wang, S.-H., Weinhold, K., Weller, R., Yela, M., Yus-Diez, J., Zdimal, V., Zieger, P., and Zikova, N.: A global analysis of climate-relevant aerosol properties retrieved from the network of Global Atmosphere Watch (GAW) near-surface observatories, Atmos. Meas. Tech., 13, 4353–4392, https://doi.org/10.5194/amt-13-4353-2020, 2020. a
Lenhardt, E., Gao, L., Hostetler, C. A., Ferrare, R. A., Burton, S. P., Moore, R. H., Ziemba, L. D., Crosbie, E., Sorooshian, A., Soloff, C., and Redemann, J.: Aerosol effective radius governs the relationship between cloud condensation nuclei (CCN) concentration and aerosol backscatter, Atmos. Chem. Phys., 25, 13747–13768, https://doi.org/10.5194/acp-25-13747-2025, 2025. a
Liang, M., Tao, J., Ma, N., Kuang, Y., Zhang, Y., Wu, S., Jiang, X., He, Y., Chen, C., Yang, W., Zhou, Y., Cheng, P., Xu, W., Hong, J., Wang, Q., Zhao, C., Zhou, G., Sun, Y., Zhang, Q., Su, H., and Cheng, Y.: Prediction of CCN spectra parameters in the North China Plain using a random forest model, Atmos. Environ., 289, 119323, https://doi.org/10.1016/j.atmosenv.2022.119323, 2022. a, b
Lin, Y.-C., Yu, M., Xie, F., and Zhang, Y.: Anthropogenic Emission Sources of Sulfate Aerosols in Hangzhou, East China: Insights from Isotope Techniques with Consideration of Fractionation Effects between Gas-to-Particle Transformations, Environ. Sci. Technol., 56, https://doi.org/10.1021/acs.est.1c05823, 2022. a
Liu, J. and Li, Z.: Estimation of cloud condensation nuclei concentration from aerosol optical quantities: influential factors and uncertainties, Atmos. Chem. Phys., 14, 471–483, https://doi.org/10.5194/acp-14-471-2014, 2014. a, b
Mace, J., Matrosov, S., Shupe, M., Lawson, P., Hallar, G., McCubbin, I., Marchand, R., Orr, B., Coulter, R., Sedlacek, A., Avallone, L., and Long, C.: STORMVEX: The Storm Peak Lab Cloud Property Validation Experiment Science and Operations Plan, Tech. rep., DOE Office of Science Atmospheric Radiation Measurement (ARM) Program, https://doi.org/10.2172/989263, 2010. a
Martins, J. A., Gonçalves, F. L. T., Morales, C. A., Fisch, G. F., Pinheiro, F. G. M., Leal Júnior, J. B. V., Oliveira, C. J., Silva, E. M., Oliveira, J. C. P., Costa, A. A., and Silva Dias, M. A. F.: Cloud condensation nuclei from biomass burning during the Amazonian dry-to-wet transition season, Meteorol. Atmos. Phys., 104, 83–93, https://doi.org/10.1007/s00703-009-0019-6, 2009. a
Nair, A. A. and Yu, F.: Using machine learning to derive cloud condensation nuclei number concentrations from commonly available measurements, Atmos. Chem. Phys., 20, 12853–12869, https://doi.org/10.5194/acp-20-12853-2020, 2020. a, b
Nair, A., Yu, F., Campuzano-Jost, P., DeMott, P., Levin, E., Jimenez, J., Peischl, J., Pollack, I., Fredrickson, C., Beyersdorf, A., Nault, B., Park, M., Yum, S., Palm, B., Xu, L., Bourgeois, I., Anderson, B., Nenes, A., Ziemba, L., Moore, R., Lee, T., Park, T., Thompson, C., Flocke, F., Huey, L., Kim, M., and Peng, Q.: Machine Learning Uncovers Aerosol Size Information From Chemistry and Meteorology to Quantify Potential Cloud-Forming Particles, Geophys. Res. Lett., 48, https://doi.org/10.1029/2021GL094133, 2020. a
Parworth, C., Fast, J., Mei, F., Shippert, T., Sivaraman, C., Tilp, A., Watson, T., and Zhang, Q.: Long-term measurements of submicrometer aerosol chemistry at the Southern Great Plains (SGP) using an Aerosol Chemical Speciation Monitor (ACSM), Atmos. Environ., 106, 43–55, https://doi.org/10.1016/j.atmosenv.2015.01.060, 2015. a
Patel, P. N. and Jiang, J. H.: Cloud condensation nuclei characteristics at the Southern Great Plains site: role of particle size distribution and aerosol hygroscopicity, Environ. Res. Commun., 3, https://doi.org/10.1088/2515-7620/ac0e0b, 2021. a
Petters, M. D. and Kreidenweis, S. M.: A single parameter representation of hygroscopic growth and cloud condensation nucleus activity, Atmos. Chem. Phys., 7, 1961–1971, https://doi.org/10.5194/acp-7-1961-2007, 2007. a, b, c
Pringle, K. J., Tost, H., Pozzer, A., Pöschl, U., and Lelieveld, J.: Global distribution of the effective aerosol hygroscopicity parameter for CCN activation, Atmos. Chem. Phys., 10, 5241–5255, https://doi.org/10.5194/acp-10-5241-2010, 2010. a, b
Pöhlker, 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, https://doi.org/10.1038/s41467-023-41695-8, 2023. a
Pöhlker, M. L., Pöhlker, C., Ditas, F., Klimach, T., Hrabe de Angelis, I., Araújo, A., Brito, J., Carbone, S., Cheng, Y., Chi, X., Ditz, R., Gunthe, S. S., Kesselmeier, J., Könemann, T., Lavrič, J. V., Martin, S. T., Mikhailov, E., Moran-Zuloaga, D., Rose, D., Saturno, J., Su, H., Thalman, R., Walter, D., Wang, J., Wolff, S., Barbosa, H. M. J., Artaxo, P., Andreae, M. O., and Pöschl, U.: Long-term observations of cloud condensation nuclei in the Amazon rain forest – Part 1: Aerosol size distribution, hygroscopicity, and new model parametrizations for CCN prediction, Atmos. Chem. Phys., 16, 15709–15740, https://doi.org/10.5194/acp-16-15709-2016, 2016. a
Quinn, P., Charlson, R., and Bates, T.: Simultaneous observations of ammonia in the atmosphere and ocean, Nature, 335, 336–338, https://doi.org/10.1038/335336a0, 1988. a
Quinn, P., Bates, T., Coffman, D., J.E., J., and Upchurch, L.: Climate roles of nonsea salt sulfate and sea spray aerosol in the atmospheric marine boundary layer: Highlights of 40 years of PMEL research., Oceanography, 36, 168–174, https://doi.org/10.5670/oceanog.2023.202, 2023. a
Rejano, F., Casans, A., Via, M., Casquero-Vera, J. A., Castillo, S., Lyamani, H., Cazorla, A., Andrews, E., Pérez-Ramírez, D., Alastuey, A., Gómez-Moreno, F. J., Alados-Arboledas, L., Olmo, F. J., and Titos, G.: Activation properties of aerosol particles as cloud condensation nuclei at urban and high-altitude remote sites in southern Europe, Sci. Total Environ., 762, https://doi.org/10.1016/j.scitotenv.2020.143100, 2021. a, b, c, d, e, f
Rejano, F., Casans, A., Via, M., Casquero-Vera, J. A., Castillo, S., Lyamani, H., Cazorla, A., Andrews, E., Pérez-Ramírez, D., Alastuey, A., Gómez-Moreno, F. J., Alados-Arboledas, L., Olmo, F. J., and Titos, G.: CCN estimations at a high-altitude remote site: role of organic aerosol variability and hygroscopicity, Atmos. Chem. Phys., 24, 13865–13888, https://doi.org/10.5194/acp-24-13865-2024, 2024. a, b, c, d, e, f, g, h
Ren, J., Zhang, F., Wang, Y., Collins, D., Fan, X., Jin, X., Xu, W., Sun, Y., Cribb, M., and Li, Z.: Using different assumptions of aerosol mixing state and chemical composition to predict CCN concentrations based on field measurements in urban Beijing, Atmos. Chem. Phys., 18, 6907–6921, https://doi.org/10.5194/acp-18-6907-2018, 2018. a
Rizzo, L. V., Artaxo, P., Müller, T., Wiedensohler, A., Paixão, M., Cirino, G. G., Arana, A., Swietlicki, E., Roldin, P., Fors, E. O., Wiedemann, K. T., Leal, L. S. M., and Kulmala, M.: Long term measurements of aerosol optical properties at a primary forest site in Amazonia, Atmos. Chem. Phys., 13, 2391–2413, https://doi.org/10.5194/acp-13-2391-2013, 2013. a, b
Rose, C., Collaud Coen, M., Andrews, E., Lin, Y., Bossert, I., Lund Myhre, C., Tuch, T., Wiedensohler, A., Fiebig, M., Aalto, P., Alastuey, A., Alonso-Blanco, E., Andrade, M., Artíñano, B., Arsov, T., Baltensperger, U., Bastian, S., Bath, O., Beukes, J. P., Brem, B. T., Bukowiecki, N., Casquero-Vera, J. A., Conil, S., Eleftheriadis, K., Favez, O., Flentje, H., Gini, M. I., Gómez-Moreno, F. J., Gysel-Beer, M., Hallar, A. G., Kalapov, I., Kalivitis, N., Kasper-Giebl, A., Keywood, M., Kim, J. E., Kim, S.-W., Kristensson, A., Kulmala, M., Lihavainen, H., Lin, N.-H., Lyamani, H., Marinoni, A., Martins Dos Santos, S., Mayol-Bracero, O. L., Meinhardt, F., Merkel, M., Metzger, J.-M., Mihalopoulos, N., Ondracek, J., Pandolfi, M., Pérez, N., Petäjä, T., Petit, J.-E., Picard, D., Pichon, J.-M., Pont, V., Putaud, J.-P., Reisen, F., Sellegri, K., Sharma, S., Schauer, G., Sheridan, P., Sherman, J. P., Schwerin, A., Sohmer, R., Sorribas, M., Sun, J., Tulet, P., Vakkari, V., van Zyl, P. G., Velarde, F., Villani, P., Vratolis, S., Wagner, Z., Wang, S.-H., Weinhold, K., Weller, R., Yela, M., Zdimal, V., and Laj, P.: Seasonality of the particle number concentration and size distribution: a global analysis retrieved from the network of Global Atmosphere Watch (GAW) near-surface observatories, Atmos. Chem. Phys., 21, 17185–17223, https://doi.org/10.5194/acp-21-17185-2021, 2021. a
Rose, D., Nowak, A., Achtert, P., Wiedensohler, A., Hu, M., Shao, M., Zhang, Y., Andreae, M. O., and Pöschl, U.: Cloud condensation nuclei in polluted air and biomass burning smoke near the mega-city Guangzhou, China – Part 1: Size-resolved measurements and implications for the modeling of aerosol particle hygroscopicity and CCN activity, Atmos. Chem. Phys., 10, 3365–3383, https://doi.org/10.5194/acp-10-3365-2010, 2010. a
Schmale, J., Henning, S., Henzing, B., Keskinen, H., Sellegri, K., Ovadnevaite, J., Bougiatioti, A., Kalivitis, N., Stavroulas, I., Jefferson, A., Park, M., Schlag, P., Kristensson, A., Iwamoto, Y., Pringle, K., Reddington, C., Aalto, P., Äijälä, M., Baltensperger, U., Bialek, J., Birmili, W., Bukowiecki, N., Ehn, M., Fjæraa, A. M., Fiebig, M., Frank, G., Fröhlich, R., Frumau, A., Furuya, M., Hammer, E., Heikkinen, L., Herrmann, E., Holzinger, R., Hyono, H., Kanakidou, M., Kiendler-Scharr, A., Kinouchi, K., Kos, G., Kulmala, M., Mihalopoulos, N., Motos, G., Nenes, A., O'Dowd, C., Paramonov, M., Petäjä, T., Picard, D., Poulain, L., Prévôt, A. S. H., Slowik, J., Sonntag, A., Swietlicki, E., Svenningsson, B., Tsurumaru, H., Wiedensohler, A., Wittbom, C., Ogren, J. A., Matsuki, A., Yum, S. S., Myhre, C. L., Carslaw, K., Stratmann, F., and Gysel, M.: Collocated observations of cloud condensation nuclei, particle size distributions, and chemical composition, Sci. Data, 4, https://doi.org/10.1038/sdata.2017.3, 2017. a, b, c
Schmale, J., Henning, S., Decesari, S., Henzing, B., Keskinen, H., Sellegri, K., Ovadnevaite, J., Pöhlker, M. L., Brito, J., Bougiatioti, A., Kristensson, A., Kalivitis, N., Stavroulas, I., Carbone, S., Jefferson, A., Park, M., Schlag, P., Iwamoto, Y., Aalto, P., Äijälä, M., Bukowiecki, N., Ehn, M., Frank, G., Fröhlich, R., Frumau, A., Herrmann, E., Herrmann, H., Holzinger, R., Kos, G., Kulmala, M., Mihalopoulos, N., Nenes, A., O'Dowd, C., Petäjä, T., Picard, D., Pöhlker, C., Pöschl, U., Poulain, L., Prévôt, A. S. H., Swietlicki, E., Andreae, M. O., Artaxo, P., Wiedensohler, A., Ogren, J., Matsuki, A., Yum, S. S., Stratmann, F., Baltensperger, U., and Gysel, M.: Long-term cloud condensation nuclei number concentration, particle number size distribution and chemical composition measurements at regionally representative observatories, Atmos. Chem. Phys., 18, 2853–2881, https://doi.org/10.5194/acp-18-2853-2018, 2018. a, b, c, d, e, f, g, h, i, j, k, l, m
Schmeisser, L., Backman, J., Ogren, J. A., Andrews, E., Asmi, E., Starkweather, S., Uttal, T., Fiebig, M., Sharma, S., Eleftheriadis, K., Vratolis, S., Bergin, M., Tunved, P., and Jefferson, A.: Seasonality of aerosol optical properties in the Arctic, Atmos. Chem. Phys., 18, 11599–11622, https://doi.org/10.5194/acp-18-11599-2018, 2018. a
Seinfeld, J. H. and Pandis, S. N.: Atmospheric Chemistry and Physics: From Air Pollution to Climate Change, John Wiley & Sons, New York, NY, USA, ISBN 9780471178156, 1998. a
Seinfeld, J. H., Bretherton, C., Carslaw, K. S., Coe, H., DeMott, P. J., Dunlea, E. J., Feingold, G., Ghan, S., Guenther, A. B., Kahn, R., Kraucunas, I., Kreidenweis, S. M., Molina, M. J., Nenes, A., Penner, J. E., Prather, K. A., Ramanathan, V., Ramaswamy, V., Rasch, P. J., Ravishankara, A. R., Rosenfeld, D., Stephens, G., , and Wood, R.: Improving our fundamental understanding of the role of aerosol−cloud interactions in the climate system, P. Natl. Acad. Sci. USA, 113, 5781–5790, https://doi.org/10.1073/pnas.1514043113, 2016. a
Shen, Y., Virkkula, A., Ding, A., Luoma, K., Keskinen, H., Aalto, P. P., Chi, X., Qi, X., Nie, W., Huang, X., Petäjä, T., Kulmala, M., and Kerminen, V.-M.: Estimating cloud condensation nuclei number concentrations using aerosol optical properties: role of particle number size distribution and parameterization, Atmos. Chem. Phys., 19, 15483–15502, https://doi.org/10.5194/acp-19-15483-2019, 2019. a, b, c, d, e, f, g
Sherman, J. P., Sheridan, P. J., Ogren, J. A., Andrews, E., Hageman, D., Schmeisser, L., Jefferson, A., and Sharma, S.: A multi-year study of lower tropospheric aerosol variability and systematic relationships from four North American regions, Atmos. Chem. Phys., 15, 12487–12517, https://doi.org/10.5194/acp-15-12487-2015, 2015. a
Shinozuka, Y., Clarke, A. D., DeCarlo, P. F., Jimenez, J. L., Dunlea, E. J., Roberts, G. C., Tomlinson, J. M., Collins, D. R., Howell, S. G., Kapustin, V. N., McNaughton, C. S., and Zhou, J.: Aerosol optical properties relevant to regional remote sensing of CCN activity and links to their organic mass fraction: airborne observations over Central Mexico and the US West Coast during MILAGRO/INTEX-B, Atmos. Chem. Phys., 9, 6727–6742, https://doi.org/10.5194/acp-9-6727-2009, 2009. a, b
Shinozuka, Y., Clarke, A. D., Nenes, A., Jefferson, A., Wood, R., McNaughton, C. S., Ström, J., Tunved, P., Redemann, J., Thornhill, K. L., Moore, R. H., Lathem, T. L., Lin, J. J., and Yoon, Y. J.: The relationship between cloud condensation nuclei (CCN) concentration and light extinction of dried particles: indications of underlying aerosol processes and implications for satellite-based CCN estimates, Atmos. Chem. Phys., 15, 7585–7604, https://doi.org/10.5194/acp-15-7585-2015, 2015. a, b, c
Shupe, M. D., Rex, M., Blomquist, B., Persson, P. O. G., Schmale, J., Uttal, T., Althausen, D., Angot, H., Archer, S., Bariteau, L., Beck, I., Bilberry, J., Bucci, S., Buck, C., Boyer, M., Brasseur, Z., Brooks, I. M., Calmer, R., Cassano, J., Castro, V., Chu, D., Costa, D., Cox, C. J., Creamean, J., Crewell, S., Dahlke, S., Damm, E., de Boer, G., Deckelmann, H., Dethloff, K., Dütsch, M., Ebell, K., Ehrlich, A., Ellis, J., Engelmann, R., Fong, A. A., Frey, M. M., Gallagher, M. R., Ganzeveld, L., Gradinger, R., Graeser, J., Greenamyer, V., Griesche, H., Griffiths, S., Hamilton, J., Heinemann, G., Helmig, D., Herber, A., Heuzé, C., Hofer, J., Houchens, T., Howard, D., Inoue, J., Jacobi, H.-W., Jaiser, R., Jokinen, T., Jourdan, O., Jozef, G., King, W., Kirchgaessner, A., Klingebiel, M., Krassovski, M., Krumpen, T., Lampert, A., Landing, W., Laurila, T., Lawrence, D., Lonardi, M., Loose, B., Lüpkes, C., Maahn, M., Macke, A., Maslowski, W., Marsay, C., Maturilli, M., Mech, M., Morris, S., Moser, M., Nicolaus, M., Ortega, P., Osborn, J., Pätzold, F., Perovich, D. K., Petäjä, T., Pilz, C., Pirazzini, R., Posman, K., Powers, H., Pratt, K. A., Preußer, A., Quéléver, L., Radenz, M., Rabe, B., Rinke, A., Sachs, T., Schulz, A., Siebert, H., Silva, T., Solomon, A., Sommerfeld, A., Spreen, G., Stephens, M., Stohl, A., Svensson, G., Uin, J., Viegas, J., Voigt, C., von der Gathen, P., Wehner, B., Welker, J. M., Wendisch, M., Werner, M., Xie, Z., and Yue, F.: Overview of the MOSAiC expedition: Atmosphere, Elementa: Science of the Anthropocene, 10, https://doi.org/10.1525/elementa.2021.00060, 00060, 2022. a
Sutton, M., Dragosits, U., Tang, Y., and Fowler, D.: Ammonia emissions from non-agricultural sources in the UK, Atmos. Environ., 34, 855–869, https://doi.org/10.1016/S1352-2310(99)00362-3, 2000. a
Tao, J., Zhao, C., Kuang, Y., Zhao, G., Shen, C., Yu, Y., Bian, Y., and Xu, W.: A new method for calculating number concentrations of cloud condensation nuclei based on measurements of a three-wavelength humidified nephelometer system, Atmos. Meas. Tech., 11, 895–906, https://doi.org/10.5194/amt-11-895-2018, 2018. a
Twomey, S.: he nuclei of natural cloud formation part II: The supersaturation in natural clouds and the variation of cloud droplet concentration, Geofisica Pura e Applicata, 43, 243–249, https://doi.org/10.1007/BF01993560, 1959. a, b
Vaishya, A., Jennings, S. G., and O'Dowd, C.: Seasonal Variation of the Aerosol Light Scattering Coefficient in Marine Air of the Northeast Atlantic, Adv. Meteorol., 2011, 170490, https://doi.org/10.1155/2011/170490, 2011. a
Varble, A., Nesbitt, S., Salio, P., Avila, E., Borque, P., DeMott, P., McFarquhar, G., van den Heever, S., Zipser, E., Gochis, D., Houze, R., Jensen, M., Kollias, P., Kreidenweis, S., Leung, R., Rasmussen, K., Romps, D., and Williams, C.: Cloud, Aerosol, and Complex Terrain Interactions (CACTI) Field Campaign Report, Tech. rep., DOE Office of Science Atmospheric Radiation Measurement (ARM) Program, https://www.arm.gov/publications/programdocs/doe-sc-arm-19-028.pdf (last access: 19 August 2025), 2019. a
Vié, B., Pinty, J.-P., Berthet, S., and Leriche, M.: LIMA (v1.0): A quasi two-moment microphysical scheme driven by a multimodal population of cloud condensation and ice freezing nuclei, Geosci. Model Dev., 9, 567–586, https://doi.org/10.5194/gmd-9-567-2016, 2016. a
Vogelmann, A. M., McFarquhar, G. M., Ogren, J. A., Turner, D. D., Comstock, J. M., Feingold, G., Long, C. N., Jonsson, H. H., Bucholtz, A., Collins, D. R., Diskin, G. S., Gerber, H., Lawson, R. P., Woods, R. K., Andrews, E., Yang, H.-J., Chiu, J. C., Hartsock, D., Hubbe, J. M., Lo, C., Marshak, A., Monroe, J. W., McFarlane, S. A., Schmid, B., Tomlinson, J. M., and Toto, T.: RACORO Extended-Term Aircraft Observations of Boundary Layer Clouds, B. Am. Meteorol. Soc., 93, 861–878, https://doi.org/10.1175/BAMS-D-11-00189.1, 2012. a
Wang, J., Cubison, M. J., Aiken, A. C., Jimenez, J. L., and Collins, D. R.: The importance of aerosol mixing state and size-resolved composition on CCN concentration and the variation of the importance with atmospheric aging of aerosols, Atmos. Chem. Phys., 10, 7267–7283, https://doi.org/10.5194/acp-10-7267-2010, 2010. a, b
Wang, N., Wang, Y., Lu, C., Zhu, B., Yan, X., Sun, Y., Xu, J., Zhang, J., and Shen, Z.: Interpretable ensemble learning unveils main aerosol optical properties in predicting cloud condensation nuclei number concentration, npj Clim. Atmos. Sci., 8, https://doi.org/10.1038/s41612-025-01181-y, 2025a. a, b
Wang, Y., Zhang, R., Wang, N., Xu, J., Zhang, J., Cui, C., Lu, C., Zhu, B., Sun, Y., and Zhu, Y.: The Role of Relative Humidity in Estimating Cloud Condensation Nuclei Number Concentration Through Aerosol Optical Data: Mechanisms and Parameterization Strategies, Geophys. Res. Lett., 25, https://doi.org/10.1029/2024GL112734, 2025b. a, b, c
Watson, T. B.: Aerosol Chemical Speciation Monitor (ACSM) Instrument Handbook, Tech. Rep. DOE/SC-ARM-TR-196, U.S. Department of Energy, Brookhaven National Laboratory, https://www.osti.gov/servlets/purl/1375336 (last access: 8 July 2025), 2017. a
Wilbourn, E. K., Lacher, L., Guerrero, C., Vepuri, H. S. K., Höhler, K., Nadolny, J., Pantoya, A. D., Möhler, O., and Hiranuma, N.: Measurement report: A comparison of ground-level ice-nucleating-particle abundance and aerosol properties during autumn at contrasting marine and terrestrial locations, Atmos. Chem. Phys., 24, 5433–5456, https://doi.org/10.5194/acp-24-5433-2024, 2024. a
Wilson, T. W., Ladino, L. A., Alpert, P. A., Breckels, M. N., Brooks, I. M., Browse, J., Burrows, S. M., Carslaw, K. S., Huffman, J. A., Judd, C., Kilthau, W. P., Mason, R. H., McFiggans, G., Miller, L. A., Nájera, J. J., Polishchuk, E., Rae, S., Schiller, C. L., Si, M., Vergara Temprado, J., Whale, T. F., Wong, J. P. S., Wurl, O., Yakobi-Hancock, J. D., Abbatt, J. P. D., Aller, J. Y., Bertram, A. K., Knopf, D. A., and Murray, B. J.: A marine biogenic source of atmospheric ice-nucleating particles, Nature, 525, 234–238, https://doi.org/10.1038/nature14986, 2015. a
Wu, Z. J., Zheng, J., Shang, D. J., Du, Z. F., Wu, Y. S., Zeng, L. M., Wiedensohler, A., and Hu, M.: Particle hygroscopicity and its link to chemical composition in the urban atmosphere of Beijing, China, during summertime, Atmos. Chem. Phys., 16, 1123–1138, https://doi.org/10.5194/acp-16-1123-2016, 2016. a
Zhou, S., Guo, F., Chao, C.-Y., Yoon, S., Alvarez, S. L., Shrestha, S., Flynn, J. H. I., Usenko, S., Sheesley, R. J., and Griffin, R. J.: Marine Submicron Aerosols from the Gulf of Mexico: Polluted and Acidic with Rapid Production of Sulfate and Organosulfates, Environ. Sci. Technol., 57, 5149–5159, https://doi.org/10.1021/acs.est.2c05469, 2023. a
Short summary
This study presents a comprehensive analysis of cloud condensation nuclei (CCN) phenomenology across nine observatories in diverse environments. We evaluate CCN prediction methods based on aerosol chemical composition and optical properties, including empirical and machine learning approaches. While simplified chemical schemes provide first-order estimates, incorporating optical data substantially improves CCN prediction accuracy in regions without direct measurements.
This study presents a comprehensive analysis of cloud condensation nuclei (CCN) phenomenology...
Altmetrics
Final-revised paper
Preprint