New data on the glaciers of the Koryak Highlands: assessment of the state using satellite images and field studies
As a result of deciphering the Sentinel-2 images (2018 and 2019), 189 glaciers were discovered in the Koryak Highlands. The reduction in glacier areas in comparison with the USSR Glacier Inventory (late 1960s) varies widely from 20 to 74%. The error of glacier size determent from space images was estimated basing on ground-based survey of glaciers from a drone (UAV) during the expedition in September 2020. Contemporary glaciers of the Highlands are mainly corrie glaciers of the northern, NE and NW aspects. The change of equilibrium line altitude in the glacier groups within the river basins, identified in the Glacier Inventory for this area, vary from a minimum rise of several tens of meters to maximum values of 400-500 m. Spatial patterns of trends in mean summer and annual temperatures, total precipitation and precipitation for the cold period from 1966 to 2019 were compiled: the values of temperature trends increase towards the Kamchatka Peninsula, and precipitation trends - from the continent to the coastal zone. The obtained ratios of these trends with the degree of glacial groups reduction makes it possible to link the trends of the regional climate with the glacial systems’ change that is the basis for predicting the reduction of glaciers for a period of several decades.