BENGALURU: An ongoing study by glaciologists has sounded an alert about at least 858 ‘hanging glaciers’ across the 2,500km-long Himalayan range in India, posing a serious threat to lives and properties of millions living in hamlets, villages and towns located downhill in the mountainous region.
Hanging glaciers are small and steep and are found on mountain slopes and cliff edges. They are extremely unstable and vulnerable to climate change.
Experts said the havoc created by them when they break is bigger because of the volume of water and ice stored in them. Glaciologists raised the alert for a catastrophe especially in summer, as melting is faster and loss of life and property can be higher because locals and tourists are present in larger numbers in the region. Elevated warming in the Himalayas has intensified this hazard, the experts have pointed out.
Data collated in the study by experts from the Bengaluru-based Divecha Centre for Climate Change (DCCC) over the last two years has revealed that, so far, of the 858 hanging glaciers found and assessed, 99 are in the Yamuna basin, 219 in the Alaknanda basin, 261 in the Bhagirathi basin and 279 in the Kali basin. The cumulative water stored in the glaciers is 3,236 gigatonnes.
Geologists assessing threat of glacier melting
The Indus basin glaciers carry 2,103 cubic km of water; Ganga basin glaciers, 596 cubic km and Brahmaputra basin glaciers, 897 cubic km.
Glacier expert Dr Anil V Kulkarni, distinguished visiting scientist at DCCC under the Centre for Atmospheric and Oceanic Sciences, Indian Institute of Science, told The New Sunday Express that the extent of damage caused by a melting-and-breaking hanging glacier cannot be precisely tabulated as it depends on the size of the glacier, the season in which the incident occurs and the number of people in the region at that point of time.
Localised effects also impact hanging glaciers apart from the degradation of permafrost (ground including soil, rock, or sediment that remains frozen at or below zero degree Celsius).
“This is one area we need to immediately understand to ensure the safety of the vulnerable communities. But lack of adequate infrastructure and manpower is making it difficult,” he said. Glaciologists, however, have said models are being developed now to understand which portions of ice form and melt first, to primarily assess the nature of threat due to melting hanging glaciers.
A grim reminder of the catastrophic impact of hanging glaciers is the November 7 disaster in Rishi Ganga Valley in which 72 people died and at least 200 were reported missing. Dr Kulkarni said the data from the study is being collated using satellite images and physical verification of hanging glaciers at accessible locations, before being listed out.
To address the threat from hanging glaciers, officials from the National Disaster Management Authority (NDMA), Ministry of Water Resources, Ministry of Earth Science and scientists from IISc recently held a meeting in which a series of suggestions was listed. During the meeting, an immediate alert was sounded over a hanging glacier in the Badrinath region.
Sources privy to the minutes of the meeting told TNSE that stress was laid on an immediate need to think beyond traditional methods and convert hazard, vulnerability and risk assessment into high mountain regulation zones to regulate developmental activities. They also pointed to the increasing cryogenic changes taking place in the Himalayan region, and stressed the need for preparing a cryosphere change impact assessment report.
