ANTHROPOGENIC CLIMATE CHANGE IN RUSSIA IN THE TWENTY-FIRST CENTURY: AN ENSEMBLE OF CLIMATE MODEL PROJECTIONS

摘要

Due to the large extent of Russia and adjacent territories, the current climate of this region is noted for its wide diversity. Additionally, a number of studies have shown a strong sensitivity of the regional climate system to atmospheric GHG concentration increases. Therefore, an assessment of possible changes in the climate of Russia in the 21st century has an important theoretical and practical value. In this study, an assessment of the climate change in major watersheds of Russia has been made for the first time using the ensemble of comprehensive AOGCMs for the A2 and B2 IPCC emission scenarios, (see also [4]). Analysis shows that the climate warming and associated precipitation increase in the watersheds of Russia in the 21st century are much greater than the corresponding global values, particularly in winter. In spite of the summer precipitation increase, drier conditions are expected to occur in a larger part of Russia than at present. This is most pronounced in southern and western watersheds and is caused by earlier snowmelt and increased evaporation from the land surface. The climate warming is associated with marked changes in the hydrological regime of the land surface, affected by cryospheric processes. In the watersheds of European Russia and southwestern Siberia, the winter snow accumulation decreases. As a result, spring runoff maxima decrease and occur earlier. In the watersheds of central and eastern Siberia, the winter snow accumulation increases, and the spring runoff maxima also increase due to increased snowmelt. Therefore, the probability of severe spring floods in this part of Russia increases.