New Delhi: More than 27 per cent of glacial lakes identified in the Himalayas have expanded significantly since 1984 and 130 of them are in India, the ISR said on Monday.
In a statement, the space agency said long-term satellite images covering catchments of Indian Himalayan river basins from 1984 to 2023 indicate significant changes in glacial lakes.
"Of the 2,431 lakes larger than 10 hectares identified during 2016-17, 67 glacial lakes have expanded significantly since 1984," it said.
The Indian Space Research Organization (ISRO) said that out of 676 lakes, 601 have more than doubled in expansion, while 10 lakes have expanded by 1.5 to two times and 65 lakes by 1.5 times.
It states that of the 676 lakes, 130 are located within India, of which 65, seven and 5 are located in the Indus, Ganges and Brahmaputra river basins respectively.Altitude-based analysis revealed that 314 lakes are located in the 4,000–5,000 m range and 296 lakes are located above 5,000 m.
Glacial lakes are classified into four broad categories based on the process of their formation – moraine-dammed (water dammed by moraines), ice-impounded (water dammed by ice), erosional (dammed water in depressions formed by erosion), Other glacial lakes lakes
Of the 676 extant lakes, the majority are moraine-dammed (307), followed by erosion (265), other (96), and ice-dammed (eight) glacial lakes.
ISRO highlighted long-term changes in the Ghepang Ghat glacial lake (in the Indus Basin), located at an altitude of 4,068 meters in Himachal Pradesh, showing a 17 per cent increase in size from 36.49 hectares to 101.30 hectares between 1988 and 2022. The increase is approximately 1.96 hectares per year.
In October, at least 40 people were killed and 76 missing after incessant rains in Sikkim caused the South Lonak Lake – a glacial lake located at an altitude of 17,000 feet in the state's northwest – to burst.The Himalayas, often called the Third Pole because of their vast glaciers and snow cover, are highly sensitive to changes in the global climate – both in terms of their physical characteristics and their social impacts.
Research conducted around the world has consistently shown that glaciers around the world are experiencing unprecedented rates of retreat and thinning due to human-caused climate change.
This withdrawal leads to the formation of new lakes and expansion of existing lakes in the Himalayan region. These bodies of water formed by the melting of glaciers are known as glacial lakes and play an important role as a source of freshwater for rivers in the Himalayan region.
However, they also pose significant risks such as glacial lake outburst floods (GLOFs), which can have devastating consequences for downstream communities.GLOFs occur when glacial lakes release large amounts of meltwater due to the failure of natural dams, such as moraines or ice dams, resulting in sudden and severe flooding. These dam failures can be caused by a variety of factors, including snow or rock avalanches, extreme weather events, and other environmental factors.
Monitoring and studying the occurrence and expansion of glacial lakes in the Himalayan region is challenging due to the inaccessible and rugged terrain.
Satellite remote sensing technology proves to be an excellent tool for reconnaissance and monitoring due to its wide coverage and observability. ISRO said it is important to assess long-term changes in glacial lakes to understand the rate of melting of glaciers, assess GLOF risks and gain information about the impacts of climate change.
In a statement, the space agency said long-term satellite images covering catchments of Indian Himalayan river basins from 1984 to 2023 indicate significant changes in glacial lakes.
"Of the 2,431 lakes larger than 10 hectares identified during 2016-17, 67 glacial lakes have expanded significantly since 1984," it said.
The Indian Space Research Organization (ISRO) said that out of 676 lakes, 601 have more than doubled in expansion, while 10 lakes have expanded by 1.5 to two times and 65 lakes by 1.5 times.
It states that of the 676 lakes, 130 are located within India, of which 65, seven and 5 are located in the Indus, Ganges and Brahmaputra river basins respectively.Altitude-based analysis revealed that 314 lakes are located in the 4,000–5,000 m range and 296 lakes are located above 5,000 m.
Glacial lakes are classified into four broad categories based on the process of their formation – moraine-dammed (water dammed by moraines), ice-impounded (water dammed by ice), erosional (dammed water in depressions formed by erosion), Other glacial lakes lakes
Of the 676 extant lakes, the majority are moraine-dammed (307), followed by erosion (265), other (96), and ice-dammed (eight) glacial lakes.
ISRO highlighted long-term changes in the Ghepang Ghat glacial lake (in the Indus Basin), located at an altitude of 4,068 meters in Himachal Pradesh, showing a 17 per cent increase in size from 36.49 hectares to 101.30 hectares between 1988 and 2022. The increase is approximately 1.96 hectares per year.
In October, at least 40 people were killed and 76 missing after incessant rains in Sikkim caused the South Lonak Lake – a glacial lake located at an altitude of 17,000 feet in the state's northwest – to burst.The Himalayas, often called the Third Pole because of their vast glaciers and snow cover, are highly sensitive to changes in the global climate – both in terms of their physical characteristics and their social impacts.
Research conducted around the world has consistently shown that glaciers around the world are experiencing unprecedented rates of retreat and thinning due to human-caused climate change.
This withdrawal leads to the formation of new lakes and expansion of existing lakes in the Himalayan region. These bodies of water formed by the melting of glaciers are known as glacial lakes and play an important role as a source of freshwater for rivers in the Himalayan region.
However, they also pose significant risks such as glacial lake outburst floods (GLOFs), which can have devastating consequences for downstream communities.GLOFs occur when glacial lakes release large amounts of meltwater due to the failure of natural dams, such as moraines or ice dams, resulting in sudden and severe flooding. These dam failures can be caused by a variety of factors, including snow or rock avalanches, extreme weather events, and other environmental factors.
Monitoring and studying the occurrence and expansion of glacial lakes in the Himalayan region is challenging due to the inaccessible and rugged terrain.
Satellite remote sensing technology proves to be an excellent tool for reconnaissance and monitoring due to its wide coverage and observability. ISRO said it is important to assess long-term changes in glacial lakes to understand the rate of melting of glaciers, assess GLOF risks and gain information about the impacts of climate change.
