Changes in the River Runoff of a Small Freeze-out River in the Continuous Permafrost Zone of Central Yakutia and Its Causes

Against the background of an increase in air temperature by 0.58°C/10 years and the absence of precipitation growth, the annual runoff of a small freeze-out river in the continuous permafrost zone statistically significantly grows by 1.9 mm/10 years, and the runoff coefficient increases by 0.9%/10 years. This is due to a shift in the river freezing to later dates and in the runoff onset to earlier ones, an increase in the runoff period, and a transition of a part of precipitation from solid into liquid one. Divergent changes in ground temperature and thaw depth indicate the absence of permafrost influence on the runoff increase. The identified patterns may be representative of numerous freeze-out rivers in the Lena and Vilyuy interfluve region.