| Summary: | Since the Little Ice Age, the altitudinal and latitudinal range of the Earth's cryogenic formations has been steadily narrowing and expressed in a progressive reduction of the glaciosphere [1]. Subject to global climatic trends, the glaciation of the Altai (Russian, Mongolian, Chinese) has been in steady regression for a century and a half, and the glaciers of its main centres demonstrate a negative mass balance and decrease in the area occupied [2,3,4,5] . A characteristic element of landscapes of the Altai periglacial belt, as an area with actively shrinking glaciation, are complexes of polygenic and polymorphic lake water bodies, the number of which increases in proportion to the rate of glaciation reduction. The uneven distribution of lakes across the mountain-glacial basins of the Altai is dictated by their morphological features: most of the lake water bodies are confined to the gentle precipices of valley and car-valley glaciers with well-defined marginal moraine complexes, which act either as natural dams or provide conditions for the development of thermokarst limnogenesis. In basins dominated by glaciers of flat-top or slope type, there are no conditions for the formation of water bodies. A comparative analysis of the space survey materials from 1968 to 2020 shows that most of them were formed in the last half-century. Lakes of the deglaciation belt are represented by the following morphogenetic types: 1. Glacial lakes. Glacial lake basins are formed in the ablation zone of valley glaciers in thermoerosional or thermokarst depressions of the glacial terrain. This type of lakes belongs to ephemeral formations; he hydrographic characteristics of this type of lakes (water area, volume) change annually with a steady upward trend due to their thermal impact on the occupied depression and natural transformation of the glacial surface. When critical volumes are reached, after a short period of time, glacial lakes empty, with a more or less pronounced degree of catastrophism. 2. Moraine lakes are formed in ...
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