Intensity of permafrost processes in Central Yakutia landscapes
Fedorov, Alexander (1)
(1) no
This paper illustrates the peculiarities of permafrost processes manifestation in various landscapes during the intense GAME observations in Central Yakutia. Observation results that were achieved at the Spasskaya Pad station within the frameworks of the GAME-SIBERIA project and at Permafrost Institute stations are used in this paper.
Earlier we analyzed retrospective scheme of evolution of air temperature, precipitations, soil temperature and active layer thickness (Federov, 2001). Period of intense observations
within the frameworks of the GAME-SIBERIA project (1996-2000) coincided with considerable increase of average annual air temperature (deviation for +1,30C). Other climate characteristics had also changed.
Data of permafrost temperature change in various landscapes are given in this paper. In present time at the territory of Central Yakutia we can observe the increase of permafrost temperature, as well as its decrease. Temperature decrease, alone with some other factors, connected with vegetation regeneration - antropogenic successions. Such
areas are rather big due to forest fires and cuttings. The rules of permafrost successions evolution in Central Yakutia has been found out. Their total duration is 130 years. Spatial model of permafrost landscapes, which helps to estimate the succession influence on thermal
regime of permafrost, has been worked out. It also allows creating retrospective and prediction models of permafrost.
Influence of permafrost conditions change on soil moisture regime of active layer has been estimated. Spatial and temporal models of water reserves of active layer during the intense GAME observations at the vicinity of Spasskaya Pad station have been created.
Special attention has been pointed to the study of protective layer of permafrost landscapes. Decreasing and destruction of the layer are very important for dynamics of permafrost. Data of field observations of surface subsidence on various sites of Permafrost Institute in
Central Yakutia in thermokarst evolution are given in the paper. Process activation in thermokarst depression and especially at the flat areas of woodless territories in inter-alases that had no thermokarst earlier has been noted.
This indicates that the period of GAME-SIBERIA observations coincided with the period of cryoecological stress in Central Yakutia landscapes. Data that were obtained by GAME-SIBERIA will create a basis for the study of formation of critical situations in permafrost landscapes and for criteria determination of permafrost stability.
Submittal Information
Name :
Date :
Fedorov, Alexander
30-Jul-04-09:29:32
Organization :
Theme :
Permafrost Institute
Theme 1
Address :
Presentation :
Merzlotnaya,1, Permafrost Institute, Yakutsk, 677010