Express News Service
NEW DELHI: A cloudburst over Lhonak Lake in north Sikkim has triggered a flash flood in the Teesta River basin, killing at least eight people. Nearly 70 others, including 22 army personnel, are missing too. The Glacial Lake Outburst Flood (GLOF) has washed away Chungthang Teesta Urja Dam. Video footage of terrible destruction has gone viral on social media.
What is GLOF?
Glacial lakes are formed due to the melting of glaciers. When the water of glacial lakes breaches their boundaries causing the release of huge amounts of floods to nearby streams and rivers is known as the Glacial Lake Outburst Flood. The threat of GLOF has increased as global warming induces glaciers to retreat at a faster rate.
According to the Central Water Commission (CWC), there are 2028 glacial lakes and water bodies of size more than 10 Ha in the Himalayan region catchment which contribute to rivers flowing in India. Of these, 1,169 glacial lakes/water bodies are located in the elevation zone 4,000m above sea level. The Teesta basin in Sikkim Himalaya hosts numerous glacial lakes in the high-altitude glacierised region, including the largest and the fastest-growing south Lhonak Lake.
Environmentalists have estimated that over 200 glacial lakes are vulnerable to outbursts. Studies have shown that infrastructure like dams, many settlements and assets are exposed to GLOFs in the Teesta Valley.
“It indicates the need to conduct a full environmental impact assessment and potentially undertake GLOF risk mitigation measures,” said Ashim Sattar, Department of Geology and Environmental Geosciences, University of Dayton, USA. Sattar co-authored a paper in 2021 on the Future GLOF hazard of the South Lhonak Lake, Sikkim Himalaya.
Environmentalists have long sought attention to hundreds of remote glacial lakes on unsettled mountain valleys. “While these lakes are mainly located in remote and unsettled mountain valleys, far-reaching GLOF may damage assets up to tens of kilometres downstream,” Sattar said.
Why is it difficult to forecast cloudburst?
Cloudburst is a small-scale phenomenon that satellites cannot detect with precision. Mrutyunjay Mohapatra, Director General of Meteorology, IMD, explained the resolution of the Indian satellite is 4 sq m in the infra-red range, while cloudburst is a single cloud that may be 1 sq km or less
Global-warming effect
Global warming leads to the retreating of glaciers and the formation of glacial lakes which further breach their boundaries causing intense floods to nearby streams and rivers known as Glacial Lake Outburst Flooding (GLOF).
Environmentalists estimated that currently over 200 glacial lakes are vulnerable to outburst
NEW DELHI: A cloudburst over Lhonak Lake in north Sikkim has triggered a flash flood in the Teesta River basin, killing at least eight people. Nearly 70 others, including 22 army personnel, are missing too. The Glacial Lake Outburst Flood (GLOF) has washed away Chungthang Teesta Urja Dam. Video footage of terrible destruction has gone viral on social media.
What is GLOF?
Glacial lakes are formed due to the melting of glaciers. When the water of glacial lakes breaches their boundaries causing the release of huge amounts of floods to nearby streams and rivers is known as the Glacial Lake Outburst Flood. The threat of GLOF has increased as global warming induces glaciers to retreat at a faster rate.googletag.cmd.push(function() {googletag.display(‘div-gpt-ad-8052921-2’); });
According to the Central Water Commission (CWC), there are 2028 glacial lakes and water bodies of size more than 10 Ha in the Himalayan region catchment which contribute to rivers flowing in India. Of these, 1,169 glacial lakes/water bodies are located in the elevation zone 4,000m above sea level. The Teesta basin in Sikkim Himalaya hosts numerous glacial lakes in the high-altitude glacierised region, including the largest and the fastest-growing south Lhonak Lake.
Environmentalists have estimated that over 200 glacial lakes are vulnerable to outbursts. Studies have shown that infrastructure like dams, many settlements and assets are exposed to GLOFs in the Teesta Valley.
“It indicates the need to conduct a full environmental impact assessment and potentially undertake GLOF risk mitigation measures,” said Ashim Sattar, Department of Geology and Environmental Geosciences, University of Dayton, USA. Sattar co-authored a paper in 2021 on the Future GLOF hazard of the South Lhonak Lake, Sikkim Himalaya.
Environmentalists have long sought attention to hundreds of remote glacial lakes on unsettled mountain valleys. “While these lakes are mainly located in remote and unsettled mountain valleys, far-reaching GLOF may damage assets up to tens of kilometres downstream,” Sattar said.
Why is it difficult to forecast cloudburst?
Cloudburst is a small-scale phenomenon that satellites cannot detect with precision. Mrutyunjay Mohapatra, Director General of Meteorology, IMD, explained the resolution of the Indian satellite is 4 sq m in the infra-red range, while cloudburst is a single cloud that may be 1 sq km or less
Global-warming effect
Global warming leads to the retreating of glaciers and the formation of glacial lakes which further breach their boundaries causing intense floods to nearby streams and rivers known as Glacial Lake Outburst Flooding (GLOF).
Environmentalists estimated that currently over 200 glacial lakes are vulnerable to outburst
