Abstracts for the 5th International GAME Conf.

3-5 October 2001

Aichi Trade Center

Nagoya Japan

MONITORING OF THERMAL STATE OF SOILS IN CENTRAL YAKUTIA

Skryabin Pavel Nickolaevich (1), Varlamov Stepan Prokopievich (1), Skachkov Yuri Borisovich (1)

The thermal state of soils is a controlling factor in the stability of landscapes and the development of cryogenic processes. In order to understand the dynamics of ground thermal regime under the influence of global climate warming and human activities, long-term monitoring studies have been carried out since 1981 in five physiographic regions of Central Yakutia. Continuous observations cover 10 terrain types and over 80 stow types . The integrated research program employs landscape, microclimatic, thermophysical, and hydrothermal techniques. In Central Yakutia, a significant climate warming has been detected after the mid 1960s. For the period 1965-1980, the air temperature trend was +0.064degC/yr, whereas in 1981-1998, it was +0.101degC/yr. Our investigations allowed quantitative estimation of long-term changes in the thermal regime of the layer of annual heat exchange both in disturbed and undisturbed areas. Neither increasing trend in the depth of seasonal thawing nor significant warming of ground was detected in undisturbed landscapes. The trend of mean annual ground temperature at the base of the active layer varies among undisturbed landscapes from low positive (0.011c0.029degC/yr) to negative (-0.013c-0.060degC/yr) values. All land-use practices exert influence of varying type and magnitude on the landscapes. After small-scale anthropogenic impacts, the landscapes are capable of restoring their basic characteristics. Subject to larger-scale impacts the original landscape environment does not recover and the thermal regime in the upper permafrost changes profoundly. Our data show that ground temperature at the base of the active layer increases by 0.5-3.8degC after fires, clear-cutting, removal of the surface cover, resulting in the development of detrimental cryogenic processes.

Submittal Information

Name : Date :
    Skryabin Pavel Nickolaevich
    17-Jul-01-12:36:58
Organization : Theme :
    Melnikov Permafrost Institute, Siberian Branch, Russian Academy of Sciences
    Theme 2
Address : Presentation :
    Permafrost Institute, Yakutsk-10, Russia 677010
    Poster or oral
Country : Abstract ID :
    Russia
    T2SPN17Jul01123658
Phone : Fax :
    NA
    (4112) 444476
E-mail :
    skachkov@mpi.ysn.ru