Today News Online Service
Chandigarh, April 20
In the backdrop of glacial outbursts and extreme weather events expected to increase because of climatic changes, a study by the Indian Institute of Technology (IIT) has called for a satellite-based real-time monitoring of Himalayan glacial catchments that can improve understanding of flood risk in the region and help inform an early flood warning system to help mitigate disasters.
This should be the future strategy to reduce loss of human lives during glacial lake outburst floods (GLOF), the study by two professors at IIT Kanpur, with support from the Department of Science and Technology, suggests.
The study has been published this week in Science, a peer-reviewed academic journal of the American Association for the Advancement of Science.
Temperature and the number of extreme rainfall events are rising at an increased rate because of climate change.
The Himalayan region, also called the Earth’s Third Pole, is home to the largest ice mass outside of the planet’s polar regions. Glaciers in this region are melting at a faster rate, creating new lakes and expanding the existing ones.
In addition, rising temperatures and extreme precipitation events make this region increasingly prone to a variety of natural hazards, including devastating GLOFs.
GLOFs occur when either a natural dam containing a glacial lake bursts or when the lake’s level suddenly increases and overflows its banks, leading to catastrophic downstream destruction as happened in 2013 after an avalanche caused the glacial moraine holding back Chorabari lake in northern India to give way, releasing a sudden torrent of water, boulders, and debris down the river valley below, resulting in the deaths of more than 5,000 people.
With climate change, these events are likely to increase in frequency and magnitude throughout the Himalayas. However, the remote and challenging Himalayan terrain and the overall lack of cellular connectivity throughout the region has made the development of early flood warning systems virtually impossible.
The scientists have also pointed out that the surge of melt-water in mountain streams is most commonly caused by cloudbursts during the monsoon time frame.
However, the sudden surge of melt-water in Dhauli Ganga, a tributary of the Ganga, in February, which is a dry season, suggests that this time frame needs to be expanded.
The catastrophe in the upper Dhauli Ganga basin is linked to processes other than precipitation events, such as snow avalanches, rock landslides and other unidentified drivers, and therefore determining all of the potential major and minor drivers behind sudden surges of melt-water into headwater streams is vital for understanding the hazard profile of the region, the scientists said.
The IIT team suggested that efforts to help mitigate GLOF events in the future should include the creation of a network of satellite-based monitoring stations that could provide in situ and real-time data on GLOF risk.
The integration of monitoring devices with satellite networks will not only provide telemetry support in remote locations that lack complete cellular connectivity but will also provide greater connectivity in coverage in the cellular dead zones in extreme topographies such as valleys, cliffs, and steep slopes,” the study said.