Earth’s Cryosphere, 2009, Vol. XIII, No. 2, p. 16-26

CHANGES IN THERMOKARST LAKE SIZE IN DIFFERENT REGIONS OF RUSSIA FOR THE LAST 30 YEARS

V.I. Kravtsova, A.G. Bystrova

Lomonosov Moscow State University, Faculty of Geography, Department of Cartography and Geoinformatis, 119992, Moscow, Vorobyovy Gory, Russia, vik@lakm.geogr.msu.su

The results of investigation of changes in thermokarst lake distribution in Russia have been presented. Investigations were based on comparison of space images, mainly from Landsat satellites, taken in the 1970s – the beginning of 1980s and in 2000s, with an interval of 20–30 years. The analysis of multitemporal images was made for 19 test sites on the Russian territory chosen in different geocryological and landscapes conditions. There were no changes on the most part of territory (11 test sites). At 3 test sites in the Northern geocryological zone (the Southern Yamal, left-bank of the Pur River, right-bank of the Yenisei River) the decrease of lake area resulted from erosion, and at the Yana–Indigirka lowland the both processes – discharge of lakes and filling of lake depressions with water – took place. In Central Yakutia a noticeable increase in lake areas (twice) was found. The increase in lake area and appearance of new small lakes occurred at 3 test sites in the Southern geocryological zone (Verhneangarsk and Barguzin depressions in Zabaikal’e, coast of the Uda River Bay in the Far East).

Key words: Thermokarst lakes, multitemporal satellite images, changes during 20–30 years.

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