Features of Diurnal Variability of Ultrafine Aerosol in the Air of the Baikal Coastal Zone and Arid Zone of Mongolia

The results of an experimental study of ultrafine aerosol characteristics in the Baikal region and the Gobi Desert are described. The comparative analysis of the dispersion composition of atmospheric aerosol in different climate conditions is carried out. It is ascertained that the total content of ultrafine aerosol in the atmosphere of the Gobi Desert is significantly lower than in the Baikal atmosphere and soil aerosols prevail. In the Lake Baikal region, nanometer-size aerosols are also present, mainly of anthropogenic and organic origin; two peaks are observable in the diurnal variations in the total number concentration of aerosols in the afternoon and evening. In the morning and afternoon, the number of nucleation-mode particles increases due to intensification of breeze circulation, which promotes transport of anthropogenic impurities from the lake and activation of photochemical reactions.