The Changes in Russian Winter Snow Accumulation during 1936–83 and Its Spatial Patterns

Abstract

Winter snow depth observations from 119 Russian stations during the years 1936?83 are selected. These irregularly spaced station data are then interpolated into 220 regular grids of 2° lat ? 5.24° long that cover a region of 50°?70°N, 30°?140°E. The spatial variation patterns of the annual Russian winter snow accumulation during the period of 1936?83 are identified by using principal components analyses. Statistically significant trends in major snow depth variation patterns are detected. A method is constructed to estimate the spatial distributions of the total amount of snow depth change based on the significant trends of component scores during the period of 1936?83. The study found that snow depth has increased over most of northern Russia and decreased over most of southern Russia during the study period. Exceptions are found in northern European Russia, where a slight decrease in snow depth has occurred and in southern west Siberia where the snow depth has increased. The total amount of snow depth increase more than compensates for the total amount of decrease in Russia. The most significant snow increase regions are found in the northern Ural Mountains (about 60°?70°N and 50°?70°E) and northern central Siberia (60°?70°N and 110°?130°E). The most significant snow decrease is found on the southern Ural Mountains (50°?55°N, 55°?65°E). An increase of 4.7% per decade in the snow depth is estimated in northern Russia (north of 60°N), which is fairly consistent with the amount of snowfall increase estimated in northern Canada in previous studies. The total snow depth change in the study region for the period of 1936?83 is estimated to be equivalent to 43.23 km3 of water. The study suggests that the winter snow depth increase in polar continents might be a circumpolar phenomena.