Spatiotemporal variability of atmospheric humidification in the territory of Buryatia during the vegetation period

The article gives an assessment of the changes in the moisture regime of Buryatia. There is an increase in the aridity of the climate of the territory. Using Selyaninov’s hydrothermal coefficient (HTC) as a criterion for atmospheric droughts we have analyzed its trends and components for the vegetation period of 1969-2019. An analysis of the HTC dynamics shows that since 2002 dry weather conditions have become more frequent. It has been revealed that the temperature regime of Buryatia with cold and little snow winters, as well as hot summers, results in the formation of arid zones on 40% of the area. Atmospheric drought is possible in any month of the vegetation period. Low snow cover and its early melting (50-60 days before the start of the vegetation period) deprive the soil of moisture, so dry conditions can be observed already in spring. At the beginning of the vegetation period, very strong aridity is observed in about 50% of cases. Droughts in Buryatia are caused not only by the absence of effective precipitation and low moisture reserves in the soil in spring, but also be the high air temperatures. During severe droughts the average monthly air temperature is 1.5-2 times higher than the average long-term values.