Streamflow of Russian Rivers under Current and Forecasted Climate Changes: A Review of Publications. 1. Assessment of Changes in the Water Regime of Russian Rivers by Observation Data

Publications on changes in river water regime in Russia under the conditions of current climate changes are reviewed. Most recent generalizations of such publications are presented in Roshydromet evaluation reports. The publication of these basic studies followed by many studies improving the conclusions of national reports. The objective of this review is to generalize the current concepts regarding the effect of climate changes in Russian Federation territory on the mean annual and maximal river runoff, primarily, based on most recent publications and the authors’ own studies. New maps, developed by the authors, are given to characterize variations of the annual and maximal runoff, including the dates of the disturbance of the stationary character of the series based on data up to 2019. Considerable attention is paid to statistical analysis of the revealed changes. The annual runoff on the average for the Russian territory is shown to tend to increase in the recent decades because of an increase in the moistening of the territory. However, the changes in the majority of the analyzed basins are statistically insignificant. The average annual runoff of rivers into the Arctic seas from the territory of Siberia and Far East has also slightly increased. Changes in the maximal runoff are more pronounced and differently directed.