Brief communication: Supraglacial debris-cover changes in the Caucasus Mountains

Abstract. Debris cover on glaciers can significantly alter melt, and hence, glacier mass balance and runoff. Debris coverage typically increases with shrinking glaciers. Here, we present data on debris cover and its changes for 559 glaciers located in different regions of the Greater Caucasus mountains based on 1986, 2000 and 2014 Landsat and SPOT images. Over this time period, the total glacier area decreased from 691.5 km2 to 590.0 km2 (0.52 % yr−1). Thereby, the debris covered area increased from ~ 11 to ~ 24 % on the northern, and from ~ 4 to 10 % on the southern macro-slope between 1986 and 2014. Overall, we found 18 % debris cover for the year 2014. With the glacier shrinkage, debris-covered area and the number of debris-covered glaciers increased as a function of elevation, slope, aspect, glacier morphological type, Little Ice Age moraines, and lithology.