Articles | Volume 23, issue 16
https://doi.org/10.5194/acp-23-9347-2023
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/acp-23-9347-2023
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
24 Aug 2023
Research article |
| 24 Aug 2023
| 24 Aug 2023
Effect of radiation interaction and aerosol processes on ventilation and aerosol concentrations in a real urban neighbourhood in Helsinki
Jani Strömberg
CORRESPONDING AUTHOR
Institute for Atmospheric and Earth System Research, Faculty of Science, University of Helsinki, Helsinki, Finland
Xiaoyu Li
Institute for Atmospheric and Earth System Research, Faculty of Science, University of Helsinki, Helsinki, Finland
Mona Kurppa
Kjeller Vindteknikk, Espoo, Finland
Heino Kuuluvainen
Aerosol Physics Laboratory, Physics Unit, Faculty of Engineering and Natural Sciences, Tampere University, Tampere, Finland
Liisa Pirjola
Institute for Atmospheric and Earth System Research, Faculty of Science, University of Helsinki, Helsinki, Finland
Department of Automotive and Mechanical Engineering, Metropolia University of Applied Sciences, Vantaa, Finland
Leena Järvi
Institute for Atmospheric and Earth System Research, Faculty of Science, University of Helsinki, Helsinki, Finland
Helsinki Institute of Sustainability Science, Faculty of Science, University of Helsinki, Helsinki, Finland
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Short summary
We conclude that with low wind speeds, solar radiation has a larger decreasing effect (53 %) on pollutant concentrations than aerosol processes (18 %). Additionally, our results showed that with solar radiation included, pollutant concentrations were closer to observations (−13 %) than with only aerosol processes (+98 %). This has implications when planning simulations under calm conditions such as in our case and when deciding whether or not simulations need to include these processes.
We conclude that with low wind speeds, solar radiation has a larger decreasing effect (53 %) on...
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