23 Uttarakhand glaciers melting rapidly as temperatures rise, study finds

Twenty-three major glaciers in Uttarakhand are melting rapidly, with rising temperatures and the geographical characteristics of individual glaciers contributing to their retreat, according to a study by scientists at the Wadia Institute of Himalayan Geology.

The study, published in Discover Geoscience by Jyoti Kumari, Girish Chandra Kothiyari, Atul Kumar Patidar and Manish Mehta, examined historical records of 23 glaciers and assessed the factors behind their melting.

Among the glaciers studied, Khatling in Tehri was found to be retreating at 88 metres per year. Milam in Pithoragarh was melting at between 32 and 37.8 metres per year, while Ramani was retreating at 32 metres per year.

Gangotri showed a retreat rate of 22.02 metres per year over a 69-year record from 1935 to 2004. A separate six-year record showed a rate of 21.3 metres per year. Satopanth in Chamoli was retreating at 26.45 metres per year, while North Nanda Devi recorded a rate of 22 metres per year.

Pindari Glacier showed an increase in its retreat rate between the two periods studied. A 121-year record from 1845 to 1966 showed a retreat of 2,840 metres, or 23.4 metres per year. Between 2000 and 2018, it retreated 825.23 metres at an annual rate of 45.85 metres.

Other glaciers recorded retreat rates including Bandarpunch at 25.51 metres per year, Chorabari at 6.8 metres, Dokriani at 21 metres, Bhagirathi at 3.7 metres, Tipra at 14.41 metres and Dunagiri at 9 metres.

The researchers found that debris-covered glaciers generally melted at slower rates than clean-ice glaciers. Khatling, Milam, Gangotri, Satopanth, Ramani and Jaundhar were identified among the glaciers experiencing particularly rapid retreat.

The study attributed the broader changes to rising temperatures and climate change, while the shape, slope and debris cover of individual glaciers also influenced their retreat. Since 2000, the rate of melting has increased sharply.

Researchers also pointed to changing precipitation patterns. Rain is increasingly occurring at elevations of up to 4,000 metres where snow previously fell. Longer summers and declining winter snowfall are also affecting the accumulation and consolidation of snow.

Continued glacier loss could increase risks from glacial lake outburst floods, avalanches and debris flows. Himalayan glaciers also provide water for irrigation, drinking and hydropower, with major rivers including the Ganga, Yamuna, Brahmaputra, Indus and Alaknanda originating in the region.