Articles | Volume 19, issue 10
https://doi.org/10.5194/amt-19-3427-2026
© 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-19-3427-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
A methodological framework for evaluating real-time bioaerosol classification algorithms
Marie-Pierre Meurville
CORRESPONDING AUTHOR
MeteoSwiss, Chemin de l'aérologie 1, 1530 Payerne, Switzerland
Bernard Clot
MeteoSwiss, Chemin de l'aérologie 1, 1530 Payerne, Switzerland
Sophie Erb
MeteoSwiss, Chemin de l'aérologie 1, 1530 Payerne, Switzerland
Environmental Remote Sensing Laboratory (LTE), École Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
Maria Lbadaoui-Darvas
MeteoSwiss, Chemin de l'aérologie 1, 1530 Payerne, Switzerland
Laboratory of Atmospheric Processes and their Impacts, School of Architecture, Civil & Environmental Engineering, École Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
Fiona Tummon
MeteoSwiss, Chemin de l'aérologie 1, 1530 Payerne, Switzerland
Gian-Duri Lieberherr
CORRESPONDING AUTHOR
MeteoSwiss, Chemin de l'aérologie 1, 1530 Payerne, Switzerland
Benoît Crouzy
CORRESPONDING AUTHOR
MeteoSwiss, Chemin de l'aérologie 1, 1530 Payerne, Switzerland
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Marilena Gidarakou, Alexandros Papayannis, Kunfeng Gao, Panagiotis Gidarakos, Benoît Crouzy, Romanos Foskinis, Sophie Erb, Benjamin T. Brem, Cuiqi Zhang, Gian Lieberherr, Martine Collaud Coen, Branko Sikoparija, Zamin A. Kanji, Bernard Clot, Bertrand Calpini, Eugenia Giagka, and Athanasios Nenes
Atmos. Chem. Phys., 26, 923–945, https://doi.org/10.5194/acp-26-923-2026, https://doi.org/10.5194/acp-26-923-2026, 2026
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Vertical profiles of pollen and biomass burning particles were obtained at a semi-rural site at the MeteoSwiss station near Payerne (Switzerland) using a novel multi-channel elastic-fluorescence lidar system combined with in situ measurements during the spring 2023 wildfires and pollination season during the PERICLES (PayernE lidaR and Insitu detection of fluorescent bioaerosol and dust partiCLES and their cloud impacts) campaign.
Sophie Erb, Elias Graf, Yanick Zeder, Simone Lionetti, Alexis Berne, Bernard Clot, Gian Lieberherr, Fiona Tummon, Pascal Wullschleger, and Benoît Crouzy
Atmos. Meas. Tech., 17, 441–451, https://doi.org/10.5194/amt-17-441-2024, https://doi.org/10.5194/amt-17-441-2024, 2024
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In this study, we focus on an automatic bioaerosol measurement instrument and investigate the impact of using its fluorescence measurement for pollen identification. The fluorescence signal is used together with a pair of images from the same instrument to identify single pollen grains via neural networks. We test whether considering fluorescence as a supplementary input improves the pollen identification performance by comparing three different neural networks.
Mária Lbadaoui-Darvas, Ari Laaksonen, and Athanasios Nenes
Atmos. Chem. Phys., 23, 10057–10074, https://doi.org/10.5194/acp-23-10057-2023, https://doi.org/10.5194/acp-23-10057-2023, 2023
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Heterogeneous ice nucleation is the main ice formation mechanism in clouds. The mechanism of different freezing modes is to date unknown, which results in large model biases. Experiments do not allow for direct observation of ice nucleation at its native resolution. This work uses first principles molecular simulations to determine the mechanism of the least-understood ice nucleation mode and link it to adsorption through a novel modeling framework that unites ice and droplet formation.
Gian Lieberherr, Kevin Auderset, Bertrand Calpini, Bernard Clot, Benoît Crouzy, Martin Gysel-Beer, Thomas Konzelmann, José Manzano, Andrea Mihajlovic, Alireza Moallemi, David O'Connor, Branko Sikoparija, Eric Sauvageat, Fiona Tummon, and Konstantina Vasilatou
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Today there is no standard procedure to validate bioaerosol and pollen monitors. Three instruments were tested, focusing on detecting particles of different sizes. Only one instrument was able to detect the smallest particles (0.5 µm Ø), whereas the others performed best at the largest tested particles (10 µm Ø). These results are the first step towards a standardised validation procedure. The need for a reference counting method for larger particles (pollen grains: 10–200 µm Ø) was emphasised.
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Atmos. Chem. Phys., 21, 17687–17714, https://doi.org/10.5194/acp-21-17687-2021, https://doi.org/10.5194/acp-21-17687-2021, 2021
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Aerosol–cloud interactions constitute the most uncertain contribution to climate change. The uptake kinetics of water by aerosol is a central process of cloud droplet formation, yet its molecular-scale mechanism is unknown. We use molecular simulations to study this process for phase-separated organic particles. Our results explain the increased cloud condensation activity of such particles and can be generalized over various compositions, thus possibly serving as a basis for future models.
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Short summary
Our method evaluates how well automatic devices can classify pollen and other airborne particles in real time. Our goal is to compare different classification systems and understand their strengths and weaknesses. By developing this evaluation process, we aim to enhance the accuracy of bioaerosol forecasts. This research is essential for improving public health and helping people manage allergies more effectively.
Our method evaluates how well automatic devices can classify pollen and other airborne particles...