ИСТИНА

In recent decades, the validity of the concept assuming the stationary character of long-term variations of meteorological and hydrological characteristics raises doubts because of the increasing instability of climate processes. The current climate changes have already caused considerable changes in the water regime and formation conditions of water resources in a number of large regions. The new situation requires a revaluation of the renewable water resources (natural resources of groundwater and surface water) because of changes in climate characteristics, which affect the formation of water balance elements in river basins. Regional estimates along with the analysis of water resources distribution in European Russia (ER) show the space and time dynamics of the surface and subsurface components of river runoff, taking into account the current features of their formation under the effect of changing climate. The work was based on up-to-date scientific and methodological principles of statistical processing and examining the time distribution of the mean annual, dry-season, and minimal water resources and their space distribution over river basins and the constituent entities of the Russian Federation. The problems solved in the study by specialists of Water Problems Institute (Russian Academy of Sciences) and Lomonosov Moscow State University are as follows: general regularities and features of water resources formation were established; the distributions of specific water availability characteristics for territories and population were evaluated; the absolute and specific amounts of water resources for river basins, federal districts, and RF constituent entities were calculated, as required for the rational use and protection of water resources.