Current dynamics of glaciers in the Tavan Bogd Mountains (Northwest Mongolia)

Current state and dynamics of main glaciers located on the eastern slopes of the Tavan Bogd Mountains in Mongolia are investigated on the basis of results obtained in 2013–2014 field observations as well as remote sensing data acquired from unmanned aerial vehicle and satellites. This study examined 39 glaciers with a debris-free glacier area of 68 km² in the Tsagaan-Gol River basin and 41 glaciers with an area of 31 km² in the Tsagaan-Us River basin in 2013. The total glacier area decreased approximately by 4.5 % (3.2 km²) in the Tsagaan-Gol basin and by 6.9 % (2.3 km²) in the Tsagaan-Us basin from 1989 to 2013. Kozlov Glacier was retreating at an average rate of 34 m/year between 2001 and 2014. Potanin Glacier was retreating slowly between 1989 and 2001 at an average rate of 5–10 m/year and more active between 2001 and 2014 at an average rate of 28 m/year. On the base of the 2005–2013 weather station data and equilibrium line altitude monitoring at the end of 2013 ablation season, we calculated different glaciological and climatic characteristics. Ablation–accumulation value amounts to 110 g/cm² at mean summer temperature on the equilibrium line of 1 °C. Mean annual amount of solid precipitation on the equilibrium line was estimated as 785 mm. We also revealed that Kara-Turek weather station located in the Russian Altai can be used as a representative for estimating climatic and glaciological characteristics of the Tavan Bogd Mountains.