Permafrost

sites from late 1990’s to early 2000’s showed that permafrost is present in two contrasting
situations: wind-blown, thinly snow-covered terrain and thick blocky sediments covered with
late-lying snow. The former situation occurs in the summit areas of the Daisetsu Mountains and
Mt. Fuji, where thin snow cover permits deep frost penetration in winter. The latter involves
talus-derived rock glaciers in deglaciated cirques in the Japanese Alps and Hidaka Mountains,
where the permafrost is possibly preserved by both intensive cooling through matrix-free
boulders and the thermal insulation effect of thick snow cover lying until late summer. Intensive
cold air ventilation also allows perennial ground ice to develop in some block slopes and lava
tubes below the timberline, even where the mean annual air temperature is considerably above
0 °C. Above mountain permafrost are situated on far south of zonal boundary of Eurasian
continental permafrost and thus might degrade significantly due to climate change. Prediction
of this change needs more understanding of modern energy balance over permafrost and
thermal stability of permafrost.
Key words: Japanese mountain permafrost, rock glaciers, ventilation, wind-blown ground
182
Spatial Rules of Dynamics of Geocryological Conditions
in Mountainous Regions of Russian Asia
M.M.Shatz 1 , Zhang R.V. 2
(1. Shats Mark Mikhailovich, candidate of geological science, Leading scientist of Permafrost Institute
677010, Yakutsk, 10, Merzlotnaya st., 36, e-mail:shatz@mpi.ysn.ru; 2. Permafrost Institute, Director,
677010, Yakutsk, 10, Merzlotnaya st., 36, e-mail: zhanq@mpi.ysn.ru)
Abstract:Long-term geocryological researches in mountain systems of the Sayan and the Altai
let us draw a number of fundamental conclusions that serve as a basis for the main theses of the
paper.
1.A combination of various natural conditions in mountainous regions of the Altai and the
Sayan determines quite considerable distribution of seasonally and perennially frozen soils.
Perennially frozen soils occupy about 20% of the region and are found at the majority of
mountain geosystems.
2. Changes in nature of permafrost development, its thickness and temperature are mainly due to
two geographic patterns of altitudinal zonality and meridional sectors. At the same time an
increase of permafrost area and its thickness, as well as a decrease of its temperature, are not
of linear dependence. General tendency of increase in severity of geocryological conditions
depending on altitude and from west to east is of complex nature.
3. Specific combination of natural-permafrost parameters within a single geosystem of the region
allows making geocryological mapping.
4. Large-scale development of mountainous regions of the Altai and the Sayan, including
industrial, civil, transportation development and engineering, mineral resource industry etc.,
should be carried out taking into consideration permafrost conditions of the region.