Water level regime of lake Baikal: current state and perspectives in the new conditions of regulation

The paper deals with some aspects of main problems of water level regulation of Lake Baikal. The analysis of water level changes for the entire period of instrumental observations for the period of 1900-2019 was carried out. A long low-water period in the basin of Lake Baikal established an endurance record in the entire history of observations. It began in the mid 90s of the last century. The situation of extraordinary low water level period in the lake basin in 2014-2015 years is discussed. A statistically significant trend of decreasing rainfall and increasing air temperature is revealed. Atmospheric precipitation affects the long-term fluctuations in the river run-off to a greater extent than the other elements of the water balance. An analysis of the inflow of water into Lake Baikal is performed. It is found that the water level of the lake almost directly depends on the water content of the Selenga River. The minimal runoff in dry periods, as well as the annual run-off, tends to decrease. It is a continuous series of low run-off, which provided the negative trend in the minimal run-off. As a result, the inflow of water into Lake Baikal in recent years was a record minimum. The problems of legal regulating the water level of Lake Baikal are discussed.