Dynamics of Sophiysky glacier (South-Eastern Altay): the late glacial maximum - XX century

Abstract

Altai mountain glaciers are the important indicators of climate variations in the inner part of Eurasia. Analysis of stadia moraines quantity will allow to find out long period temperature and precipitation fluctuations during Late Pleistocene-Holocene if the sufficient number of absolute dates is available. Our researches show the importance of the local oroclimatic conditions for correct estimation of the long-term climate cycles. These conditions have the strong influence on timing, quantity and amplitude of glacier advances. The authors consider the accepted scheme of eight synchronous glacier retreats with 1850-year rhythm inapplicable to Altai glaciers. Now we can study only short period climate fluctuations, juxtaposing them with the modern dynamic of glacier retreats, it is possible due to the permanent monitoring and historical and meteorological data available. The article presents also the Sophysky glacier's retreat velocity data in 20 century. Both historical information and monitoring data were used for this purpose. These monitoring data were obtained during the field researches held by joint Russian-Belgian scientific group in 1997-2000 years. Radiocarbon data have allowed to estimate more precisely the duration of Little Ice Age in Altai. According to this data LIA began in 13^th century but not in 16 ^th as it was considered earlier.