Home – Home – Jornals – Geography and Natural Resources 2022 number 1

The synchronism and asynchrony of variations in the annual runoff of 18 major rivers (153 pairs of the rivers) in the Asian part of Russia were estimated by the new original methodology. The methodology is based on taking into account three groups of water discharges of the rivers (years of low, moderate and high water discharges) and on the numeric rating of the runoff in the years being compared. The runoff of the rivers is assigned to a particular group of water discharge by using its mean value over many years. The years in which the runoff was less than 0.95 of its mean value over many years were assigned to the years of low water discharge, and the years with the runoff larger than 1.05 were assigned to the years with high water discharge. The years with moderate water discharge included the values of the runoff in the interval 0.95-1.05 of the multiannual mean value. The runoff of the years with low, moderate and high water discharge was identified by number 1, 2 and 3, respectively. A comparison of water discharges was made for all 153 pairs of river basins for the correlative periods of observation under investigation. The years with identical water discharges (1 - 1, 2 - 2, 3 - 3) were assigned number 1; the years with opposite water discharges (1 - 3, 3 - 1) were characterized by number -1, and the years with adjacent water discharges (1 - 2, 2 - 1, 2 - 3, 3 - 2) were identified by number 0.5. For each pair of the rivers we estimated the numeric sum expressed in fractions of the total period of observation: the parameter of synchronism (asynchrony) of variations in the runoff. For 18 pairs of river basins the values of the parameter of synchronism were equal or exceeded 0.5. For these pairs of the rivers it was determined that the contribution from the years of low, high and a moderate discharges to the synchronism averaged 45.1 %, 36.3 and 10.7 %, respectively. The years with adjacent discharges showed an increase in the synchronism parameter by 29.2 %, whereas the years with opposite discharges decreased the synchronism by 21.3 %. The synchronism was also assessed by using the method of correlation.