Changes of the Abramov Glacier (Alay Ridge) from 1850 to 2014

Abstract

The purpose of this study was to determine the nature and rate of changes of the Abramov glacier over the period from 1850 to 2014. The glacier is located on the Alay Ridge in Kyrgyzstan. Its borders were estimated by means of interpretation and analysis of space images from the satellites Landsat-2, 5, 7, 8, KH-4А and KH-9 (program Corona), Geoеye-1 together with aerial photographs and topographical maps, and with addition of results of the field survey of the glacier’s tongue by GPS instruments. As a result, we could find that the longstanding degradation of the glacier continued over the whole period under investigation, and against the background of that there were periods of relative stabilization of the front of the tongue as well as the periods of the glacier advances of different duration and intensity. In 1850, the total area of the glacier accounted for 26.4 km2, but by 2014 it reduced by 3.65 km2, or 13.8%, and became equal to 22.75 km2. Thus, annual reduction of the glacier area was equal approximately to 0.02 km2 per a year, and its length decreased by almost 2950 m, i.e., the glacier contracted, on the average, by 18 m per a year. It should be noted that changes of the glacier area were similar during both the initial and final periods of observations, and it means that no intensification of anthropogenic impact upon the glacier was observed. Obviously, this fact is indicative of the prevalence of natural factors in the change of the glacier, expressed in irregular duration of cyclic changes.