Home – Home – Jornals – Geography and Natural Resources 2022 number 4

We suggest a method of assessing the presence of groups of years with low, medium and high discharges in the flow of major rivers in Asian Russia for a particular observing period. The river discharge was associated with a particular group of discharge by using its average long-term value. The years with discharges smaller than 0.95 or larger than 1.05 of its average long-term value were referred to low or high discharge rivers, respectively. The years with medium discharge included the values of discharge which varied from 0.95 to 1.05 of the average long-term value. It was found that the discharges of the eight major rivers of Asian Russia (Ob, Yenisei, Lena, Yana, Indigirka, Kolyma, Amur and Kamchatka) relatively often include groups of rivers with different discharges: low, medium and high. Most often the length of these groups varies from two to five years. However, the runoff of the Amur river showed groups of low and high discharges with a length of 10 years. The discharge of the Indigirka river showed one group with a length of nine years. The proportion of groups with a length of one year, which are not included in groups of years of different discharges, with respect to the total number of years made up: Ob - 23,5 %, Yenisei - 45, Lena - 43, Yana - 28,8, Indigirka - 26,7, Kolyma - 30,2, Amur - 38,7, and Kamchatka - 36,1 %. The probability change of years with a particular discharge for other discharges was assessed. It is established that in the runoff of the rivers of Asian Russia the probabilities for years with low and high discharges only to persist are the highest.