Dynamics of Intracontinental Glaciers of Siberia and East Asia since the Little Ice Age

We present results from a 10-year study of the local features of mountain glacier dynamics in Central Asia—from the latitudes of the middle taiga of Cisbaikalia and Transbaikalia, through the mountains of the steppe zone of Mongolian Altai and the desert zone of China to the cold deserts of the Himalayas. Multitemporal satellite images were interpreted, making it possible to obtain quantitative information on changes in the area and length of glaciers in key areas of the studied mountain territories. These data are linked to climatic parameters, absolute altitude, permafrost, morphology and tectonics of the mountain ridges, and anthropogenic impact. The study revealed a general trend: the retreat of glaciers starting in the 1970s, with an increase in the average annual air temperature in the Northern Hemisphere by 1.4‒1.6°С. Accelerated glacier melting and a reduction in glacier length were observed from 1990 to 2020, when the most significant warming occurred. The following years with above-average temperatures are highlighted: 1990, 1995, 1997, 2002, 2005, 2005, 2007, 2008, 2011, 2012, 2016, 2019, and 2020. This period also witnessed an increase in the area and length of some glaciers studied in 2013‒2015 and in 2021 associated with abnormal winter precipitation in 2012, 2013, and 2020. It was found that in the mountains in the south of Eastern Siberia, the aforementioned years showed a slowdown in the reduction of the area of glaciers, an increase of the number of perennial snow patches, and an increase in the frequency of snow avalanches. It has been revealed that the glaciers in Siberia, Mongolian Altai, and the Altyn-Tag Range retreated from the terminal moraines of the Little Ice Age by an average of 500 m; on the Karlyktag Range, 800‒900 m; and in the Himalayas (Langtang area), from 1 to 4.5 km.