A Study of the Influence of Atmospheric Aerosol Sources on the COVID-19 Contamination Cases Using Meteorological and Extinction Data

Abstract

Background: Even if the people density, habits and displacements probably represent the most important causes of the SARS-Cov-2 virus propagation, the role of the atmospheric aerosol needs to be investigated. Therefore, we aimed to study if the aerosol properties related to the different sources and meteorological conditions we can observe in urbanized areas can have an influence on in the atmospheric transport of the SARS-Cov-2 virus. This study focuses on the lockdown period to reduce the differences in the social behavior.Methods: We have investigated the contamination cases of four specific geographic areas, two in France and two in Italy, located in both continental and coastal areas with regard to the meteorological conditions and the corresponding air mass properties. To this end, we used a survey of meteorological conditions and aerosol properties via both the optical depth (AOD) and Angstrom exponent retrievals for these locations during March 2020. Results: The results show that the analysis of aerosol ground-based data can be of interest to assess a virus survey. In particular, our data show that moderate to strong onshore winds occurring in coastal regions, which allow large sea-spray production episodes deal with smaller COVID-19 contamination rates. One possible reason is the coagulation of SARS-Cov-2 particles with hygroscopic salty sea-spray aerosols that would tend to inhibit its viral infectivity in environments with high relative humidity via possible reaction with NaCl. Conclusions: In this paper, we hypothesize that marine atmosphere conditions tend to decrease virus infectivity. In contrast, the atmospheric transport of the SARS-Cov-2 can be favored by its coagulation with anthropogenic aerosols, which protects the virus particle from ambient humidity and preserves its infectivity.