Short-period variations in microphysical characteristics of aerosol nanoparticles in the dry steppe zone of southern Russia in summer
D.P. Gubanova, O.G. Chkhetiani, L.O. Maksimenkov
A.M. Obukhov Institute of Atmospheric Physics Russian Academy of Sciences, Moscow, Russia
Keywords: atmosphere, dry steppe zone, south of Russia, aerosol, nanoparticles, nucleation mode, Aitken mode, transient subfraction, counting concentration, daily variation, particle size distribution, meteorological parameters
Abstract
The first results of summer field observations of the microphysical characteristics of ultrafine aerosol particles in the near-surface layer of the atmosphere in the dry steppe zone of southern Russia in 2021 and 2022 are considered. Taking into account the synoptic and meteorological conditions, the daily changes in concentration and size distribution of ultrafine aerosols, as well as their short-term variability are studied. The constant presence of Aitken particles is established at any time of the day and under any meteorological conditions. Minimal concentrations of nucleation particles and Aitken particles are detected at night and in the early morning. The highest rate of generation of nucleation particles is typical for the morning hours, when photochemical processes are activated, thus causing the morning maxima of concentrations of nucleation and Aitken particles. During the night hours, an increase in the concentration of transient subfraction particles is observed. The features of the short-period variability of ultrafine aerosols in the dry steppe zone of southern Russia are discussed taking into account the general pattern of daily aerosol generation dynamics and subsequent particle growth in the atmosphere, as well as by comparing with the results of observations of ultrafine aerosols in some other regions of the world.
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