For a number of large river basins of the European Russia (total area 1, 88 million km2), the analysis of average annual river flow, precipitation, evaporation, potential evaporation, runoff coefficient, and aridity index for 3 periods was carried out: 1945–1977, 1978–2002, 2003–2015. It was found that on average the second period, compared with the first, is characterized by high precipitation

Abstract

For a number of large river basins of the European Russia (total area 1, 88 million km2), the analysis of average annual river flow, precipitation, evaporation, potential evaporation, runoff coefficient, and aridity index for 3 periods was carried out: 1945–1977, 1978–2002, 2003–2015. It was found that on average the second period, compared with the first, is characterized by high precipitation (+4,3 %), evapotranspiration (+3,2 %), river flow (+6,1 %), runoff coefficient (+1,8 %). The potential evapotranspiration is almost not increased (+0.09%), resulting in a increase in the aridity index (+4,2 %). The third period is characterized by high values of the basic water balance characteristics in comparison with the first period, but smaller in comparison with the second. A positive anomaly of precipitation (+2,4 %) and potential evapotranspiration (+5,8 %), have led that the third period, unlike the second, was more arid than the first (index of aridity -3,2 %).