Vol. 21, issue 06, article # 3

Abstract:

The influence of the Tomsk city on the chemical and disperse composition of surface atmospheric aerosols has been estimated by means of carrying out several continuous measurement campaigns at two different sites. One of the sites was located at the rural area (Kireevsk village, 60 km west of Tomsk), and another one - at the eastern suburb of the city. In conditions of predominant zonal westerlies, air masses first passed through the rural site, then Tomsk, and finally reached the suburban measurement site. It is shown that the determining factors in formation of aerosol field over a moderate city are the prehistory of air masses and the activity of erosion processes in summer. The influence of the direct anthropogenic urban emissions on the mesoscale variability of atmospheric aerosol is insignificant. On the whole, dispersion aerosol composition changes slightly except for the increase in the number density in the city. However, a significant transformation occurs in the structure of element and ion distribution over particles of different dispersities: additional concentration peaks for fine (d < 0.5 µm) and coarse (d > 10 µm) particles of heavy metals were found; peaks in distribution of ions and elements of natural origin tend to the region of coarse particles.