Dimensional changes in the Kolahoi glacier from 1857 to 2014

This study assimilates data from historical records (1857-1961/84), survey of India topographic maps, and a series of multispectral satellite data (1962-2014) for analyzing the shrinkage and dimensional changes of the Kolahoi glacier, Jammu and Kashmir, between 1857 and 2014. The composite results show that the glacier has receded by ∼3423 m (21.8 m/year) in the past 157 years. The historical records reveal that the glacier retreated by >1609 m from 1857 to 1909, 800 m from 1912 to 1961, and 210 m from 1961 to 1984. From 1962 to 2014 (52 years), we observed a retreat of 1014 ± 64 m (19.5 ± 1.1 m/year). We noted a marked disparity in the retreat rates of primary snout (PS) and secondary snout (SS) which was found to be 19.5 ± 1.1 m/year for PS and 11.34 ± 1.1 m/year for SS. Further, our investigations reveal that the changes in the length are accompanied by considerable changes in the area. The area of the glacier reduced from 14.46 ± 0.34 km² (1962) to 11.28 ± 0.21 km² (2014) amounting an overall deglaciation of 3.18 ± 0.34 km² or 22.99 ± 2.3% in the past 52 years. Besides, the glacier has started degenerating at a much accelerated pace showing a deglaciation of 11.1 ± 1.9% and a recession rate of ~27.8 ± 3.2 m/year in just 14 years (2000-2014). These results warrant the detailed studies regarding various controlling factors, besides the climate change.