Assessment of Variations in the Annual Sum of Active Temperatures and Total Precipitation during the Vegetation Period in Russia and Neighboring Countries

E. N. Popova, I. O. Popov, and S. M. Semenov

The long-term values are calculated for the annual sum of active temperatures in the surface air layer and for total precipitation during the vegetation period (May–September) in Russia and neighboring countries for two time periods: 1951–1970 and 1991–2010. The statistical procedures are used to demonstrate the reliability of differences in the values of these parameters for the analyzed time periods. The sum of active temperatures significantly increased almost on the whole territory of Russia except for some Arctic and Far East regions. The spatial variations in total precipitation during the vegetation period are obviously inhomogeneous.