Influence of the modern climatic setting in the mountains of Central Asia on the state of glaciation, glacier runoff and glacial lake outbursts

Abstract

The climatic setting of Central Asia in the second half of the 20th century and in the first decade of the 21st century is characterized by a change of horizontal and vertical temperature gradients at the western periphery of the Central Asian Mountain system. The growth of summer air temperatures led to the decrease of mountain glaciations. In the last 45 years the glaciers in selected catchments of Gissar-Alay lost about 16% in area while the glaciers of the Pskem river catchment lost 27% in area. The river regimes, primarily the annual distribution of runoff react to the glacier decrease. The share of glacial runoff is over 25% in years with little precipitation, while it considerably decreases in years with abundant precipitation. One of the negative consequences of the glacier decrease is the formation of lakes in the periglacial area. The state of glacial lakes should be monitored, because they may pose outburst debris flow hazard.