Regional changes in air temperature and precipitation in the valleys of the middle reaches of the Lena river

Abstract

Currently, about 45% of the population of the Republic of Sakha (Yakutia) lives in the valley of the middle reaches of the Lena River. The effects of climate change to varying degrees can have both negative and positive impacts on the lives of these people. The purpose of this article: to identify the features of changes in air temperature and precipitation regime in the study area. The paper uses methods of statistical analysis and scientific generalization. Meteorological series of three stations located in the valley of the middle reaches of the Lena River – Namtsy, Yakutsk and Pokrovsk – were analyzed. The air temperature is taken for the period 1961-2024, which covers the old base period 1961-1990 and the current climatic norm 1991-2020. The series of atmospheric precipitation were analyzed for the period 1966-2024. To simplify the task, the period from May to September was taken for the warm period, and the period from October to April for the cold period. Statistically significant trends in annual air temperature were revealed, the rate of change in Pokrovsk is 0.4 ° C/10 years, in Yakutsk and Namtsy 0.6 ° C/10 years. The sums of the daily temperatures of the warm period increased significantly. Analysis of precipitation did not find statistically significant trends; graphical visualization of their dynamics provides insight into significant year-to-year variability. At all stations since 2014, there has been a decrease in the amount of precipitation of the warm period, and in the last 5 years – an increase in the amount of precipitation of the cold period. The results obtained can be used when adopting plans for regional adaptation measures in the Republic of Sakha (Yakutia), in particular, for its central, most populated part.