FEATURES OF GLACIATION IN THE NORTHERN BAIKAL AREA AT THE BEGINNING OF THE 21st CENTURY
M.D. Ananicheva1, A.A. Abramov2, Yu.M. Kononov1, I.A. Patrikeeva3, G.Yu. Pakin1
1Institute of Geography, RAS, Staromonetniy per. 29, Moscow, 119017, Russia
2Institute of Physico-Chemical and Biological Problems in Soil Science, RAS, Pushchino, Institutskaya str. 2, 142290, Russia
3Lomonosov Moscow State University, Leninskie Gory 1, Moscow, 119991, Russia
Keywords: Baikal, glacier, permafrost, satellite image, temperature, precipitation, dendrochronology, paleoreconstruction
Abstract
Glaciation of the northern Baikal region is associated with mountain ranges surrounding Lake Baikal. The underlying rocks are in the frozen state. The existing glaciers are remnants of a larger Pleistocene glaciation, and their area is subjected to continuous shrinking. The analysis of tree cores allowed us to reconstruct the climatic background of the glaciation changes in the recent past. A dendroclimatic curve is divided into two parts: the first part lasted until about 1860-1865, when the summer air temperature was almost always below the mean summer temperature for the entire considered period (~16 °С); the second part (until now) is characterized by higher (above-average) temperatures. During the field work, the current state of the regional glaciation was described for the areas of the Baikal, Barguzin, and Verkhneangarsk ranges. The areas of glaciation were determined from the Landsat 7 and Sentinel-2 satellite images for 2000 and 2021 and were controlled by orthophotoplans based on the UAV survey in August 2021. The maximum reduction of glaciated area over 21 years is generally typical for small forms of glaciation and reaches 10-30 % for the main glaciers. Data on temperature regime of air and rock surface along an altitudinal profile in the Verkhneangarsk Range were obtained for the first time.
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