ABSTRACT
Changes in the atmospheric composition during different periods of 2020 in Moscow which were associated with the COVID-19 pandemic preventing measures as well as corresponding pollutant emission reduction, are investigated. Surface concentrations of nitrogen dioxide (NO2), carbon monoxide (CO), ozone (O3), aerosol fraction (PM10), and meteorological parameters during different periods of 2020 were compared with similar data for the previous five years. The analysis of ground-based measurements, as well as of high-resolution satellite distributions of CO and NO2 indicated that the concentration of major pollutants and its spatial distribution in the Moscow region were significantly affected by both restrictive measures and abnormal meteorological conditions in 2020.
ABSTRACT
The paper studies variability in mass concentration and elemental composition of near-surface aerosol in Moscow in March-April 2020. During the study period, noticeable fluctuations in concentration of surface aerosol caused by atypical synoptic and meteorological conditions were revealed. Sharp increase in PM10 particle concentration (March 25-29, April 13) is associated with anticyclonic activity and advection of air containing combustion aerosols from the areas with biomass fires. In April as a whole, anomalously low values of aerosol particle concentrations were recorded in comparison with the long-term average. The prevailing dry Arctic air masses significantly decreased the atmospheric aerosol pollution. The decrease of anthropogenic load during COVID-19 non-proliferation actions affected on daily variations of the surface aerosol, smoothing out its typical daily maximal concentration values. Results of spring experiment at the IAP RAS showed good agreement with the data of the Obuchi nearest station of State Budgetary Institution "Mosecomonitoring". We analyzed geochemical spectrum of chemical elements in aerosol and its variability under different synoptic and weather conditions in Moscow. Possible sources and sinks of aerosols are discussed taking into account both abnormal weather conditions and decreased anthropogenic load during a lockdown period in the spring of 2020.