In this paper we present some results of the summer expedition in 1994 undertaken to study the dynamics of diurnal variations of the atmospheric aerosol concentration. The measurements are being conducted simultaneously at three points of Novosibirsk region. Comparison of the measurement data at different points of Novosibirsk region allows one to draw the conclusion on the dynamics of natural diurnal cycles and their anthropogenic distortions. Comparison of the summer measurements with those in other seasons reveals seasonal variations in the atmospheric aerosol concentration.