EVALUATION OF LONG-TERM CHANGES IN RADIATION, CLOUDINESS, AND SURFACE-TEMPERATURE ON THE TERRITORY OF THE FORMER SOVIET-UNION

Regular measurements of solar radiation carried out in the network of actinometric stations of the former Soviet Union (FSU) have shown a de creasing tendency in the time series of direct and global solar radiat ion during last decades. A statistically significant decrease has been found in 60% of the time series of global radiation annual totals obt ained from 160 actinometric stations. Three large areas, where this de crease exceeded 2% per 10 years, were found (in the European part of t he FSU, in West Siberia, and in the Far East). As the main reason for changes in solar radiation, increased cloudiness and atmospheric turbi dity are considered. A more detailed analysis of long-term changes in radiation budget components obtained from two stations situated in rat her different conditions (Moscow Meteorological Observatory in a large town and Toravere Actinometric Station in a rural area) allows us to point out the influence of a large town as a source of air pollution o n the radiation transfer in the atmosphere, as well as on cloudiness a nd air temperature.