Annual behavior of Angstrom exponent of the aerosol absorption coefficients in the visible wavelength range upon the results of measurements at the aerosol station of IAO SB RAS

The seasonal and inter-annual variability of the monthly average values of the Angstrom exponent of aerosol absorption in the wavelength range 460-630 nm is studied based on the results of measurements of the aerosol absorption coefficients of the dry matter of submicron aerosol at the aerosol station of IAO SB RAS in 2010-2017 in the nearground air layer. For each year and for the entire period, the range of the Angstrom parameter variations, features of its average annual behavior and inter-annual dynamics are analyzed. It is revealed that the annual variability of the monthly average values of the parameter is characterized by minimum values of ∼1.0 ÷ 1.4 in winter and their increase up to 1.8 ÷ 2.4 in the warm period of year. It is shown that increase of the Angstrom exponent is caused mainly by the effect of smokes from Siberian forest fires, as well as vegetation fires in the spring and autumn seasons.