River Terek Glacial Basin Degradation Dynamics on the Background of Current Climate Change

Abstract

In Georgia, on the ridge of the Greater Caucasus, there are well-developed, rather high glaciers. The study of glaciers has gained more importance since the second half of the twentieth century due to the negative impact of current climate change, which has led to significant and rapid degradation of glaciers, exacerbating natural disasters of glacial origin. Due to the degradation of glaciers in the country, a change in the water balance and degradation of landscapes, an increase in the level of the Black Sea, and the growth of the natural disasters frequency and intensity of glacial origin are having a place. This poses a serious threat to the sustainable development of the country and, therefore, the study of glaciers has become a priority in the research program of Georgia. Using satellite remote sensing, GIS technologies, glacial catalogue, field ground observations and expert knowledge, the negative impact of modern climate change was revealed and, as a consequence, the dynamics of degradation of glaciers in the glacial basins of East Georgia was studied in detail. In this article, the dynamics of the degradation of glaciers in the glacial basins of River Terek is overviewed. For this purpose, a comparison is made of the state of glaciers (area and number) for three time periods. The initial state is taken to be the state of glaciers in this basin at the time of the finish of the glaciers researches (1960). The data gathered were published in several editions of the glacier catalogue. Subsequent states - middle (2015) and final (2020) are determined using high-resolution satellites. Technological and methodological research proved to be effective for studying the dynamics of glacier degradation based on innovative high-resolution satellite remote sensing since the best practices were used in conjunction with the methods developed by the authors. A comparison of these conditions showed that the area and number of glaciers are greatly decreasing due to climate change. It should be noted that the dynamics of glacier degradation is nonlinear, which makes the melting of glaciers in the second period more intense than in the first. This conclusion also confirms one of the main theses of the 6th IPCC report that the main problem is not climate change, but its speed.