Geospatial observations of topographical control over the glacier retreat, Miyar basin, Western Himalaya, India

Abstract

Himalayan glaciers show large spatial variation in glacial retreat and mass loss due to their unique climate setting, altitude and topography. Large variability of glacier response to climate in this region may be due to various factors such as climatic (precipitation, temperature, humidity, wind, etc.) and non-climatic (topography and debris cover). In this study, an attempt has been made to understand the role of topographical parameters and debris cover for glacier recession in Miyar basin, Western Himalaya. Miyar basin is one of the major contributors of water discharge to Indus basin, which has significant population dependent upon the glacier runoff. A total of 29 glaciers covering an area of ~ 227 km^-2 were studied. The glacier retreat for the period 1989–2014 was estimated using the satellite data of Landsat series (TM, ETM and OLI). Topographical features such as size, aspect, slope and debris cover were extracted from the Landsat Operational Imager scene and ASTER GDEM V2 data. These glaciers were classified based on flow direction, area covered, slope and debris coverage. Observations revealed almost 9 ± 0.7 km^-2 recessions in glacier area (4%) for studied glaciers of Miyar basin during 1989–2014. Within the Miyar basin glaciers with large size, having a steep slope with high debris cover and northward aspect showed low retreat than glaciers of small size, gentle slope and low debris cover with southward aspect.