Climate and Environmental Changes and its Impact on the Scythian Frozen Toms of the Altai Mountains, South Siberia, Russia.

Abstract:

Many components of the cryosphere, particularly glaciers and permafrost, react sensitively to climate changes. Climate projections for the 21st century suggest there could be pronounced warming and degradation of permafrost with a corresponding shift in landscape and ecosystem settings. Air and soil temperature data from Altai, Tien Shan, Tibet and Mongolian mountain regions show a significant rise in permafrost temperatures during the past 30-40 years. The geothermal observations and modelling indicate that in the mountains of central Asia are more favorable conditions for permafrost occurring and preservation exist inside of the blocky material (coarse debris) where the mean annual temperatures are usually 3-5°С colder than the mean annual air temperature (MAAT). It is a reason we have found archaeological artefacts inside of Scythian tombs (ca 2.5 K Years before present) partially in frozen state. The tomb's construction has a blocky heap up to 2 meters in height and 16-20 meters in diameter. But climate warming pushes us and historical artefacts to new environments. The most significant impact on permafrost thermal state were observed near the lower boundary of alpine permafrost, the region where the frozen ground is very sensitive to changes in the surface energy balance. In the high-mountain regions, the further near-surface permafrost degradation will probably accompany a transformation of the environmental conditions and may lead to slope instability and permafrost-related hazards such as landslides, active layer detachment, thermokarst, and mudflows as well as thawing of Scythian tombs frozen core. Our modeling result shows the frozen tombs located near the altitudinal lower boundary of permafrost distribution are most vulnerable to climate warming as well as the tombs with coarse debris layer less than 1.5-2 m in thick and less than 16-20 m in diameter.