We study the composition of near-surface aerosol in the center of Moscow and in its suburb (near Zvenigorod - west of Moscow) in the period 25.03-03.05.2020. The concentrations of different aerosol size-fractions, as well as the concentrations and enrichment factors of a number of chemical elements of different genesis, their correlations and particle size distributions are managed, in addition to source emissions, by long-range atmospheric transport of air masses and meteorological parameters. During the observation period, both points were in the similar meteorological and synoptic conditions, which caused high correlations of mass concentrations of different aerosol fractions between the city and the suburb. In the last days of March, the regional atmospheric transport of smoke and dust aerosols from neighboring areas with multiple biomass fires created a sharp increase in the total aerosol content and its chemical element concentrations in the air both in the city (the daily MPC value for PM10 particles was exceeded) and in the suburb. The first estimates of the spring rates of removing aerosols of different sizes and individual chemical elements from the atmosphere with air humidity increase were made for Moscow region. The conditions forming the composition of near-surface atmospheric aerosol in megapolis and in its suburb are discussed.
|