Fitting of the particle size distributions by lognormal functions in the frameworks of empirical classification of the “aerosol weather” types

Variability of the volume distribution functions in the submicron and coarse size ranges in each season and under four type of “aerosol weather”: «background», «Haze-S», «Smog» и «Smoke haze» is analyzed on the basis of the data on daily mean values of the number concentration of the near-ground atmospheric aerosol obtained by means of an optical counter at the Aerosol Monitoring Station of IAO SB RAS in 2000-2017. The analyzed data arrays were formed in the «σd–Р» coordinates, where σd is the scattering coefficient of the aerosol dry matter at the wavelength of λ = 0.51 μm), P is the ratio of the mass concentration of the absorbing substance to the mass concentration of submicron particles. The fitting of the particle volume distribution was carried out as a superposition of two broad lognormal distributions of submicron and coarse particles. The average values of the fitting parameters are presented for all seasons (winter, spring, summer, autumn) and all types of the aerosol weather.