Fig. 2. Contours of glaciers No. 139 (Magushkhara, 143c), No. 140 (Magushkhara, 143d), No. 141 (northern Magushkhara) and No. 142: a − according to the topographic map, b − according to the Landsat 7 ETM+ sensor image of August 31, 2010, c − according to the Landsat 8 OLI TIRS TIRS sensor image of September 5, 2015, d − according to the Landsat 8 OLI TIRS sensor image of September 11, 2020.