AR - recent papers

Iberulite fall and formation mechanism during a Sahara dust event in Switzerland in February 2021

Tue, 13 Oct 2026 13:09:07 +0200

Iberulite fall and formation mechanism during a Sahara dust event in Switzerland in February 2021
Bernard Grobety, Philippe Favreau, Juanita Rausch, David Jaramillo-Vogel, Martin Steinbacher, and Christoph Neururer
Aerosol Research, 4, 485–500, https://doi.org/10.5194/ar-4-485-2026, 2026
The iberulite fall was, to our knowledge, the first reported in central Europe. What was special was that the fall was observed in situ and that the meteorological conditions during the fall are well known. The meteorology and the particle size distribution inside the iberulites strongly corroborate below-cloud scavenging as a probable formation mechanism. The discovery of further iberulites Saharan dust event (SDE) samples collected since suggests that iberulites are common but overlooked by other researchers.

Chemical Speciation and Source Apportionment of PM2.5 in Greek Urban and Suburban Areas: Insights from the PANACEA Initiative

Wed, 07 Oct 2026 13:09:07 +0200

Chemical Speciation and Source Apportionment of PM2.5 in Greek Urban and Suburban Areas: Insights from the PANACEA Initiative
Stefanos Papagiannis, Evangelia Diapouli, Vasiliki Vasilatou, Maria Gini, Konstantinos Kourtidis, Christos Kaltsonoudis, Maria Tsagkaraki, Georgios Grivas, Eleni Liakakou, Αikaterini Bougiatioti, Nikolaos Mihalopoulos, and Konstantinos Eleftheriadis
Aerosol Research Discuss., https://doi.org/10.5194/ar-2026-35,2026
Preprint under review for AR (discussion: open, 0 comments)
This study investigated fine particulate air pollution across five Greek cities to identify its primary sources. By chemically analyzing over 545 24-hour air filter samples, we mapped seasonal patterns and identified seven major emission sources. Marked differences show that while regional background pollution strongly affects PM2.5 levels, local activities, particularly winter wood burning for residential heating, remain a primary cause of urban air degradation in Greece.

Drivers governing the seasonality of new particle formation in the Arctic

Tue, 06 Oct 2026 13:09:07 +0200

Drivers governing the seasonality of new particle formation in the Arctic
Dominic Heslin-Rees, Peter Tunved, Diego Aliaga, Janne Lampilahti, Ilona Riipinen, Annica M. L. Ekman, Ki-Tae Park, Martina Mazzini, Stefania Gilardoni, Roseline Thakur, Kihong Park, Young Jun Yoon, Kitack Lee, Mikko Sipilä, Mauro Mazzola, and Radovan Krejci
Aerosol Research, 4, 457–483, https://doi.org/10.5194/ar-4-457-2026, 2026
New particles form in the atmosphere and can influence the climate. We studied Arctic new particle formation (NPF) from 2022 to 2024 at the Zeppelin Observatory, on Svalbard. NPF occurs from April to November, peaking in late spring as sunlight increases. Some particles measured on-site grow large enough to seed clouds. Sunlight and existing aerosol particles strongly impact the likelihood of NPF, which mainly originates from marine regions, particularly the Greenland Sea.

Dispersion normalisation method for improved long-term trend evaluation: heavy metals in ambient air in the Czech Republic, Central Europe (2010–2021)

Mon, 05 Oct 2026 13:09:07 +0200

Dispersion normalisation method for improved long-term trend evaluation: heavy metals in ambient air in the Czech Republic, Central Europe (2010–2021)
Adéla Holubová Šmejkalová, Radek Lhotka, Hana Škáchová, and Jan Pacner
Aerosol Research, 4, 441–456, https://doi.org/10.5194/ar-4-441-2026, 2026
This research examined whether legislative measures to reduce heavy metal pollution have been effective in the Czech Republic. We analysed 12 years of data from 16 monitoring stations and used a method that reduces the influence of changing weather. The results showed that this method is suitable for evaluating long-term trends and helps avoid errors in interpreting pollution levels affected by year-to-year weather differences.

A metrological calibration facility for particle number counters used in emission measurements

Fri, 25 Sep 2026 13:09:07 +0200

A metrological calibration facility for particle number counters used in emission measurements
Anza Waheed, Jorge Saturno, Arpit Malik, Johannes Rosahl, Sonja Pratzler, and Andreas Nowak
Aerosol Research Discuss., https://doi.org/10.5194/ar-2026-33,2026
Preprint under review for AR (discussion: open, 1 comment)
Vehicle exhaust contains ultrafine soot particles that can harm health and the environment. Particle number measurements are essential because these particles contribute little to particulate mass. PTB developed a calibration facility producing stable soot particles of defined sizes for testing particle counters. Instruments are compared with a reference linked to national standards. The facility improves measurement accuracy and comparability between laboratories and supporting authorities.

Chemical composition of indoor and outdoor particles in a building near an international airport: Influence of local and long-range transported air pollution

Tue, 22 Sep 2026 13:09:07 +0200

Chemical composition of indoor and outdoor particles in a building near an international airport: Influence of local and long-range transported air pollution
Sami D. Harni, Delun Li, Ville Silvonen, Laura Salo, Teemu Lepistö, Toni Tykkä, Mohamed Elsayed, Luis Barreira, Sanna Saarikoski, Ilpo Kulmala, Jarkko V. Niemi, Heidi Hellén, Arto Säämänen, Topi Rönkkö, and Hilkka Timonen
Aerosol Research Discuss., https://doi.org/10.5194/ar-2026-32,2026
Preprint under review for AR (discussion: open, 2 comments)
In this study, indoor and outdoor pollutant concentrations were measured in a mechanically ventilated building in the immediate vicinity of a busy international airport. The measurement period included a strong long-range transport event. Clear differences in indoor outdoor ratios were observed between different pollutants and between normal and long-range transport periods. This study highlights the significance of a intake filtration system in indoor pollutant concentration management.

Look-up tables for complex refractive index correction of particle sizes measured by common research-grade optical particle counters

Wed, 16 Sep 2026 13:09:07 +0200

Look-up tables for complex refractive index correction of particle sizes measured by common research-grade optical particle counters
Paola Formenti and Claudia Di Biagio
Aerosol Research, 4, 429–440, https://doi.org/10.5194/ar-4-429-2026, 2026
This study improves the accuracy of optical particle counters (OPCs), instruments used to measure airborne particles important for air quality and climate research. Because OPC measurements depend not only on particle size but also on composition and shape, results can be uncertain. The paper provides a standardized database of correction factors for five commercial OPCs, helping researchers produce more reliable and consistent aerosol measurements across a wide range of atmospheric conditions.

Complex refractive indices of flame soot from different combustion conditions retrieved using Mie and RDG-FA theories: a simulation chamber study

Wed, 16 Sep 2026 13:09:07 +0200

Complex refractive indices of flame soot from different combustion conditions retrieved using Mie and RDG-FA theories: a simulation chamber study
Johannes Heuser, Claudia Di Biagio, Jérôme Yon, Mathieu Cazaunau, Antonin Bergé, Edouard Pangui, Marco Zanatta, Laura Renzi, Angela Marinoni, Chenjie Yu, Servanne Chevaillier, Daniel Ferry, Michel Maillé, Paola Formenti, Benedicte Picquet-Varrault, and Jean-François Doussin
Aerosol Research Discuss., https://doi.org/10.5194/ar-2026-31,2026
Preprint under review for AR (discussion: open, 0 comments)
We retrieve refractive indices of laboratory-generated soot from measured particle properties using Mie and RDG-FA optical calculations, and quantify uncertainties via Monte Carlo simulations. The inferred refractive indices strongly depend on the theory employed, highlighting the need for consistency between optical theory and refractive index. Mie retrievals are sensitive to coagulation and size growth, while RDG-FA retrievals depend strongly on the uncertainty of assumed particle morphology.

Coral reef exposure increases aerosol and cloud condensation nuclei over the Great Barrier Reef

Wed, 09 Sep 2026 13:09:07 +0200

Coral reef exposure increases aerosol and cloud condensation nuclei over the Great Barrier Reef
Juha Sulo, Magdalena Okuljar, Joel Alroe, Zijun Li, Eva Johanna Horchler, Luke Cravigan, Branka Miljevic, Luke Harrison, Daniel Harrison, and Zoran Ristovski
Aerosol Research, 4, 413–427, https://doi.org/10.5194/ar-4-413-2026, 2026
The Great Barrier Reef is the world’s largest coral reef system, and the air above it plays a role in cloud formation. Using direct measurements taken over several years, this study shows that although the reef has low aerosol concentrations, air that passes directly over coral reefs contains more very small particles, providing the first direct evidence that reefs add particles to the atmosphere. These locally produced particles make a measurable contribution to cloud formation over the reef.

Atmospheric new particle formation enhanced by tricarboxylic acids

Mon, 07 Sep 2026 13:09:07 +0200

Atmospheric new particle formation enhanced by tricarboxylic acids
Astrid Nørskov Pedersen, Yosef Knattrup, and Jonas Elm
Aerosol Research, 4, 397–411, https://doi.org/10.5194/ar-4-397-2026, 2026
We investigated the new particle formation (NPF) potential of three atmospherically relevant oxygenated organic molecules (OOMs) using high-level computational methods. Cluster thermodynamics and formation rates were evaluated for systems containing sulfuric acid and various nitrogen bases. All three OOMs enhanced cluster formation, with dimethylamine-containing clusters showing the greatest effect. Pinyl diaterpenylic ester formed the most stable clusters due to its molecular flexibility.

Challenges in measuring sticky biogenic ice-nucleating macromolecules

Fri, 04 Sep 2026 13:09:07 +0200

Challenges in measuring sticky biogenic ice-nucleating macromolecules
Joseph Robinson, Martin I. Daily, Polly B. Foster, Jack P. Macklin, James B. McQuaid, Mark D. Tarn, and Benjamin J. Murray
Aerosol Research, 4, 373–396, https://doi.org/10.5194/ar-4-373-2026, 2026
Ice formation in many clouds is initiated by airborne particles, which are often measured by collecting them on a filter and washing them into water for analysis. Using controlled laboratory experiments, we show that some of these particles adhere strongly to the filter and are not recovered. As a result, this common method can underestimate how many ice-forming particles are present in the atmosphere.

Measurement-Model Closure of Sub-20 nm Particle Charge Fractions under Varying Trace Gas Composition

Tue, 04 Aug 2026 13:09:07 +0200

Measurement-Model Closure of Sub-20 nm Particle Charge Fractions under Varying Trace Gas Composition
Fabian Schmidt-Ott, Robert Nishida, Sebastian Schmitt, Jason Olfert, George Biskos, and Juha Kangasluoma
Aerosol Research Discuss., https://doi.org/10.5194/ar-2026-29,2026
Preprint under review for AR (discussion: final response, 2 comments)
Typical MPSS measurements rely on bipolar diffusion charging, where the steady-state particle charge distribution depends on charger ion properties. By simultaneously measuring ion properties and particle charge fractions, we show that Hoppel&Frick theory accurately describes charging of sub-20 nm particles. By introducing siloxanes via outgassing from conductive silicone tubing, we further show that ion properties, and thus particle charge distributions, are sensitive to trace-gas composition.

Contributions of Fine and Coarse Particles to Light Absorption at an Urban Traffic Site during Street Dust Season

Fri, 24 Jul 2026 13:09:07 +0200

Contributions of Fine and Coarse Particles to Light Absorption at an Urban Traffic Site during Street Dust Season
Luis M. F. Barreira, Delun Li, Jussi Hoivala, Minna Aurela, Aki Virkkula, Jarkko V. Niemi, Hanna E. Manninen, Topi Rönkkö, Hilkka Timonen, and Sanna Saarikoski
Aerosol Research Discuss., https://doi.org/10.5194/ar-2026-28,2026
Revised manuscript under review for AR (discussion: final response, 3 comments)
Urban street canyon measurements during spring showed that submicron particles (PM1) dominated light absorption and black carbon from traffic exhaust, while coarse particles (PM2.5–PM10) became important during dust resuspension events. Size-resolved optical and chemical analyses revealed strong source-dependency, with coarse fractions influencing absorption metrics and source apportionment, especially during street dust events, which highlighted the importance of selected particle size cut-off.

Assessment of cabin filtration efficiency: contribution to an on-road methodology

Tue, 21 Jul 2026 13:09:07 +0200

Assessment of cabin filtration efficiency: contribution to an on-road methodology
Ambre Delater, Sébastien Fable, Brice Berthelot, Cécile Raventos, Jessica Queron, Isabelle Coll, and Olivier Le Bihan
Aerosol Research Discuss., https://doi.org/10.5194/ar-2026-25,2026
Preprint under review for AR (discussion: final response, 2 comments)
Currently, the performance of automotive cabin filtration systems is assessed in laboratories, but this does not take into account all real-world parameters, such as weather conditions. To complement these studies, we evaluated the performance of two cabin filters in a moving SUV in Paris. This protocol was applied to 2 different filters, revealing differences in their filtration performance. This protocol could help researchers to understand the mechanisms of aerosol filtration in cars.

From seeding to detachment: leveraging deep learning to quantify the transport of tyre wear microplastics in a wind tunnel

Mon, 20 Jul 2026 13:09:07 +0200

From seeding to detachment: leveraging deep learning to quantify the transport of tyre wear microplastics in a wind tunnel
Bashir Olasunkanmi Ayinde, Wolfgang Babel, Johannes Olesch, Daniel Wagner, Seema Agarwal, Christian Laforsch, Julian Brehm, Anke Nölscher, and Christoph Karl Thomas
Aerosol Research, 4, 345–372, https://doi.org/10.5194/ar-4-345-2026, 2026
The dynamics of how tyre wear particles behave prior to their entrainment are still poorly understood. In wind tunnel experiments, the particle detachment from an idealized glass substrate was monitored. For particle sizes above 80 μm, smaller and more rounded particles were mobilized by wind shear first, whereas larger and more angular particles require stronger wind shear, highlighting strong surface adhesion and particle morphology as the major factors influencing microplastic detachment.

Size distribution and particle morphology of analytes dried through the evaporative light scattering detector – Part 1

Wed, 15 Jul 2026 13:09:07 +0200

Size distribution and particle morphology of analytes dried through the evaporative light scattering detector – Part 1
Frederick Bertani, Joshua Hassim, and Simone Hochgreb
Aerosol Research, 4, 311–323, https://doi.org/10.5194/ar-4-311-2026, 2026
This paper presents the very first measurements of droplet and particle sizes and concentrations through the parts of an elastic light scatter detector. Measurements were made using two instruments, phase Doppler particle anemometry and an aerodynamic aerosol classifier, to resolve the size distribution of volatile particles upstream and dried particles downstream. The final measurements are used in a companion paper comparison with simulations.

Simulation of aerosol transport, evaporation and scattering in the Evaporative Light Scattering Detector – Part 2

Wed, 15 Jul 2026 13:09:07 +0200

Simulation of aerosol transport, evaporation and scattering in the Evaporative Light Scattering Detector – Part 2
Frederick Bertani, Joshua Hassim, and Simone Hochgreb
Aerosol Research, 4, 325–344, https://doi.org/10.5194/ar-4-325-2026, 2026
The paper presents a model for the atomization and evaporation of a stream of solvents containing less volatile analytes through a system, designed to detect the final dried particles using elastic scatter, called elastic light scatter detector. The results of simulations of the total particle concentrations, as well as the final light scattered signals, are compared to experiments for validation. This is the first set of simulations of this detection device.

Exploring ice nucleation particle concentrations in a boreal environment: limits of machine-learning-assisted variable screening

Thu, 09 Jul 2026 13:09:07 +0200

Exploring ice nucleation particle concentrations in a boreal environment: limits of machine-learning-assisted variable screening
Yusheng Wu, Zoé Brasseur, Dimitri Castarède, Paavo Heikkilä, Jorma Keskinen, Ottmar Möhler, Markku Kulmala, Tuukka Petäjä, Erik S. Thomson, and Jonathan Duplissy
Aerosol Research, 4, 293–309, https://doi.org/10.5194/ar-4-293-2026, 2026
Clouds in cold regions affect climate and precipitation, but their behavior depends on rare airborne particles that help ice form. We measured these particles over several months in a Finnish forest and compared them with many environmental observations. We found that ice formation in winter was largely unpredictable, while in spring and summer it was more strongly linked to particle amount and composition. This shows that local conditions are needed to better represent clouds in climate models.

Soot growth by monodisperse particle dynamics coupled with computational fluid dynamics

Mon, 06 Jul 2026 13:09:07 +0200

Soot growth by monodisperse particle dynamics coupled with computational fluid dynamics
Arash Fakharnezhad, Joseph D. Berry, and Eirini Goudeli
Aerosol Research, 4, 279–291, https://doi.org/10.5194/ar-4-279-2026, 2026
A computationally efficient monodisperse particle dynamics–computational fluid dynamics simulation is developed to predict soot particle growth in flames without use of reaction kinetic models. The proposed model is in good agreement with soot volume fraction and mobility size measurements, demonstrating a level of accuracy comparable to that of sectional models. This model can be readily used for design applications of engines and industrial burners.

Nascent titanium-/silicon-containing particle formation in corona-discharge-assisted combustion

Wed, 01 Jul 2026 13:09:07 +0200

Nascent titanium-/silicon-containing particle formation in corona-discharge-assisted combustion
Chanakya Bagya Ramesh, Frank Daoru Han, and Yang Wang
Aerosol Research, 4, 265–277, https://doi.org/10.5194/ar-4-265-2026, 2026
We have attempted for the first time to elucidate the mechanism of inorganic particle formation and growth in sub-10 nm size. Results show that by introducing corona discharge into a flame, based on precursor concentration, we can either promote or suppress particle formation and growth. This can help better understand the effect of plasmas on combustion synthesis of nanoparticles.