Spatial Distribution of Potential Sources of Carbonaceous Aerosols in Central Siberia

Abstract

We present the results of trajectory analysis of long-term measurements of organic (OC) and elemental (EC) carbon in aerosols sampled on quartz filters at an altitude of 300 m at ZOTTO station. The EC and OC concentrations were determined by the thermo-optical method. The resulted time series were supplemented with the HYSPLIT backward trajectories, and CWT and PSCF functions were calculated on a grid of 150 × 250 cells, which covered the geographical area of 30° × 20° centered at Zotino. These functions characterize the intensity of potential sources of carbon-containing aerosols in a cell. The results make it possible to identify the regions with the strongest organic and elemental carbon emissions and to estimate the seasonal variability of these emissions. In particular, in summer, the main sources of OC and EC are located to the east of Zotino, in the Podkamennaya Tunguska River region, and are most likely associated with wildfires. In cold seasons, most sources of carbonaceous aerosols are in the southwestern part of the geographical region under study, where large cities are located and the bulk of the population is concentrated. The regression analysis of CWT functions of organic and elemental carbon is shown to enable determining the dominant type of carbonaceous aerosol sources in some cases. Our results can be used for estimation of aerosol radiative forcing in Siberia.