Mass balance of Chhota Shigri glacier using dual-polarized C band SAR data

Abstract

The Chhota Shigri glacier of the Himalaya has been monitored by dual-polarized Synthetic Aperture Radar (SAR) data to estimate mass balance for four consecutive years, 2012–2015. A liner decision rule based classification model has been developed previously and is employed to identify glacial zones throughout the ablation and accumulation periods to study transition of the zones and their temporal changes. Equilibrium Line Altitudes (ELAs) and mass balances of the glacier for the four years are calculated using the SAR derived classified outputs. The mass balance figures are − 0.65, − 0.59, − 0.25 and − 0.03 m water equivalent (w.e.) for the years 2012–2015, which are close to the previously reported mass balance figures. The work mainly demonstrates the application of the linear decision rule based classification model to study the transient glacial zones throughout the year and the use of the classified outputs to determine ELAs and mass balances of the glaciers. Optical remote sensing data are also used for comparison and showed a good match with the SAR data derived results. The SAR data based methodology is independent of glacier location and season of study; therefore, less user intervention is required, which makes the procedure more robust and objective.