Temporal variability of atmospheric aerosol optical depth over European territory of Russia according to data of the ground-based and satellite observations: tendency of aerosol "enlightenment"

The results of studies of atmospheric aerosol over the territory of Russia are of great interest from the point of view of ecological and climatic problems. The paper presents the results of spatial and temporal variability of Aerosol Optical Depth (AOD) over the European territory of the Russian Federation in the period 1999 – 2016 yy. The assessments were carried out using the original AOD extraction method based on ground-based observations of the Russian actinometric network, and also on the satellite observations of MODIS. The general regularities of spatial variations in the aerosol optical depth over Russia are revealed: a monotonic decrease from the southwest to the northeast with localized areas having different aerosol loads due to the global and regional factors of their formation. The AOT increase in spring and summer is associated with a seasonal increase in temperature and humidity and with changes in the underlying surface. "Purification" of the atmosphere from aerosol is caused by the absence of large volcanic eruptions and by industrial "calm" conditions during the last decade. Negative tendencies are less pronounced in the fall than in spring and summer. To compare the atmospheric AOT values obtained from the MODIS, AERONET and GMS data, we have compiled a combined archive of daily AOT values synchronized in pairs for the 3 types of observations (GMS, MODIS and AERONET): "Aerosol optical thickness of the atmosphere by satellite and ground observations ". The data of the comparison of terrestrial and satellite data for AOD are presented only in averaged form and need further consideration.