Permafrost

educing were the reasons of more than 50 percent of extreme situations. Especially this
circumstance is important for the areas near the southern periphery of permafrost.
The Laboratory of the General Cryology of Institute of Natural Resources, Ecology and
Cryology of the Siberian Branch of the Russian Academy of Science developed the model of
Transbaikalia permafrost dynamics for the last 500000 years. The basic results include the
following:
We developed the complex approach to the definition of initial and boundary model
conditions;
We got the principal morphometric characteristics and worked out the maps of permafrost
distribution for different cold and warm past periods in Transbaikalia;
We found that the periods of degradation and forming of permafrost were repeatedly
proceeded in Pleistocene and Holocene times. The increasing and reduction oscillations of the
permafrost thickness had the similar intensity;
We got the evaluation of the lateral dynamics of the permafrost southern border in
Transbaikalia during Pleistocene and Holocene times;
We found that the most active degradation of permafrost under influence of global
warming is linked with the technogenesis.
Field researches as a whole confirm the above-mentioned results. Within last 100 years in
Southern Transbaikalia the permafrost bodies with thickness up to 20-30 m were completely
degraded. In the same time in the North of Transbaikalia the active layer depth were increased
to 20-30 % along with the destruction of glaciers and long-term icing bodies.
The executed researches showed a high importance of the combination of scientific and
applied research for maintaining the effective management in Subarctic areas in conditions of
global climate change.
Key words: Transbaikalia, pleistocene, climate change, permafrost degradation.
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Periglacial Lake Environments in Eastern Siberia
Diekmann, B. 1 , Andreev, A.A. 1 , Gerasimova, M. 2 , Lüpfert, H. 1 ,
Nazarova, L. 1 , Pestryakova, L. 2 , Popp, S. 1 , Siegert, C. 1 , Subetto, D.A. 3
(1.Alfred Wegener Institute for Polar and Marine Research, Research Station Potsdam, Potsdam, Germany,
2.Department of Ecology, Yakutsk State University, Yakutsk, Russia, 3 Institute of Limnology, Russian Academy
of Sciences, St. Petersburg, Russia)
Abstract: Research work during the last decades highlighted the role of the northern
high-latitude regions for global climate variability. The climatic influence arising from the vast
periglacial regions of eastern Eurasia is poorly understood. Those regions were only affected by
regional mountain glaciations, are covered by Taiga and Tundra vegetation and are
characterized by deep-reaching frozen ground. In particular, Yakutia in the northeastern part of
Eurasia represents one of Earth’s most extreme climate regions with semiarid continental
climate and coldest winter temperatures on the northern hemisphere. The landscape of Yakutia
is occupied by widespread lake districts. Lacustrine sediment records of these lakes provide the