Glacier surface velocities in the Jankar Chhu Watershed, western Himalaya, India: Study using Landsat time series data (1992–2020)
This datasets presents a spatial and temporal surface velocity analysis of 33 glaciers in the Jankar Chhu Watershed (JCW), western Himalaya. The surface velocity was computed using the Co-registration of Optically Sensed Images and Correlation (COSI-Corr) tool on the Landsat images spanning nearly three decades (1992–2020). Glaciers in the JCW exhibit three distinct spatial velocity patterns. The type-I glaciers show nearly stagnant (<5 m yrˉ1) debris-covered tongues but a maximum velocity of >60 m yrˉ1 in the debris-free accumulation area. The type-II glaciers exhibit active tongues (>50 m yrˉ1) yet have slow movement in the accumulation zone. The type-III glaciers show prolonged (<10 m yrˉ1) yet consistent movement throughout the flow line. Results show that the average surface velocity of studied glaciers was 11.10 ± 4.1 m yrˉ1 in 1992/93, which increased (by ∼43%) to 15.87 ± 2.4 m yrˉ1 in 2000/02 and further increased (by ∼59%) to 25.25 ± 1.5 m yrˉ1 in 2017/18. Glaciers show seasonal fluctuations in surface velocities with an apparent “summer speedup” of ∼19%–200% compared to the winter velocities. Inter-annual velocities show an increasing trend during the observation periods.
Steps to reproduce
Glacier surface velocities were derived using the COSI-Corr tool, an addin in ENVI software.