a
b
c
d
Fig. 18. Contours of glacier No. 198: a − according to the topographic map, b − according to the image of the Landsat 7 ETM+ sensor of August 31, 2010, c − according to the image of the Landsat 8 OLI TIRS sensor of September 5, 2015, d − according to the image of the Landsat 8 OLI TIRS sensor of September 11, 2020.
