CHANGES IN SURFACE CLIMATE (AIR TEMPERATURE AND PRECIPITATION) IN RUSSIA IN THE 21ST CENTURY

The changes in the main climate variables that determine the atmospheric hydrological cycle and the hydrological regime of land (surface air temperature and precipitation) are considered for the first decades of the 21st century, as well as in comparison with the most significant changes during the 20th century. Regional changes in seasonal climate statistics were estimated using monthly CLIMATE data, and the ones for significant intraseasonal anomalies were evaluated using daily SYNOP data; both data was taken from the archives of the station data of the regular climate monitoring of the Russian Federation, which is carried out at Izrael Institute of Global Climate and Ecology. For the joint consideration of climate change and the hydrological regime of land on a regional scale, the climatic parameters were averaged over the catchment areas of largest rivers, and the catchments of the great Siberian rivers were additionally divided into the northern and southern parts. For numerical assessment of the changes, the regional averages for 2000-2011 and 2012-2023 were compared. It has been shown that in general, the Russian Federation and the considered catchments experience a temperature rise continuing the warming of the last decades of the 20th century. The annual precipitation on the territory of the Russian Federation is increasing at an average rate of 1.9% of the normal per decade (or 9.1 mm per decade). The fastest growth is observed in the spring season, which accounts for a half of the increase in annual precipitation. The features of the North Caucasus region are considered, and it is found that the summer precipitation in the region is decreasing against the background of a rapid increase in both average temperature and seasonal duration of heat waves: the proposed interpretation of this phenomenon links it with the changes in the large-scale circulation and surface temperature of the North Atlantic.