О РЕЖИМАХ СНЕЖНОСТИ ЦЕНТРАЛЬНОЙ АЗИИ В 2001–2021 гг.

Abstract

The aim of the work is to study the patterns in long-term snow regime of highland pastures of the Inner Tien Shan. Methods: The daily Snow Depth FEWS NET scenes for Central Asia were used for monitoring of snow cover of four test sites. Three test sites were located on the plains of South Kazakhstan near Tien Shan mountains. The primary test site was a highland pasture in Inner Tian Shan mountains. This is the Aksai-Chatyrkul basin, with an area of about 2800 km2, located in the altitude range of 3200-3500 m above sea level, in Kyrgyzstan on the border with China.Time series of the average seasonal snow depth for each test site were formed, which meant the average snow depth from January 1 to March 31. Monitoring for 2001-2021 years was carried out. A first-order autocorrelation was calculated for each time series. Results: The analysis indicated that the snow cover depth of neighboring years are rather poorly related to each other for three test sites located on the plains of Southern Kazakhstan. In contrast to the S outh Kazakhstan plains, the highland Inner Tien Shan pasture was characterized by pronounced persistence ("long memory effect"). Conclusion: The highland Inner Tien Shan pasture are characterized by the presence of pronounced persistence in the long-term dynamics of the average snow depth in January-March. That is, it is more likely that after a many-snow year there will be a many-snow one, and after a low-snow year, respectively, a low-snow one. The probable cause of this phenomenon is the persistence in the long-term dynamics of the seasonal characteristics of the Siberian anticyclone, which affects the ability in the cold period to atmospheric transport of water vapors through the mountain ranges of the Northern and Western Tien Shan to the Inner Tien Shan. This pattern in the long-term dynamics of highland pasture snow depth in Inner Tien Shan can be useful for long-term planning of calendar dates of spring migration of livestock from winter plain pastures to highland summer pastures.