Glacial lake outburst: Why they are a big threat for the Himalayas
According to the National Disaster Management Authority (NDMA), 189 glacial lakes in the Indian Himalayas are considered high risk, with most located in the Central and Eastern Himalayas.
Damage reported in Dharali market area due to flash floods triggered by a cloudburst at Kheer Gad area of Uttarkashi district, Uttarakhand. (PTI)
Speaking about the frequency of GLOFs, Ashim Sattar, Assistant Professor at IIT Bhubaneswar, said, 'There is no frequency of it, as till now we have three major GLOF events.''We do not have the trend of increasing or decreasing frequency of such outbursts. And also, there is not enough data on long-term frequency. Whatever is available doesn't give distinct frequency data.'WHY HAVE THEY BECOME A THREAT IN THE HIMALAYAS?The Indian Space Research Organisation (ISRO) had earlier released a report on the expanding glaciers in the Himalayan region. The report revealed that many glacial lakes have rapidly expanded in the region.It mentioned that, out of 2,431 glacial lakes larger than 10 hectares, 676 have expanded significantly, with 130 of these located in India.'Smaller lakes, even the supraglacial lakes, are causing big disasters. That is a matter of concern,' said Ashim. Steep topography, high seismic activity, and increasing global warming have intensified the severity of GLOFs in the Himalayan region, along with heavy rainfall, snowmelt, landslides, and rockfalls.Human interventions, such as infrastructure development near glacial lakes, can also trigger an outburst. For example, the Chamoli GLOF disaster of 2021 was linked to hydroelectric projects in the area.HOW TO PREVENT SUCH OUTBURSTS?Preventing disasters from GLOFs requires proper monitoring before an event occurs. India has installed early monitoring systems at Sikkim's Shakho Chho Glacial Lake.Monitoring glacial lake outbursts in time can help prevent downstream disasters. Glacial lakes in India are tracked using satellite images. 'To reduce this risk of damage to infrastructure and communities, early warning systems can be an option, so that people will have enough time to evacuate,' said Ashim.advertisement'They have been monitored by satellite data to see how they are changing over time. But monitoring would not solve the problem of disasters.'The topography of the Himalayas makes monitoring difficult. 'High regions are difficult to monitor, but satellite images can help us,' Ashim expressed hope. WHAT NEEDS TO BE DONE?The threat of GLOFs could loom larger in the coming years due to a warming climate.This calls for a comprehensive risk management strategy, the utilisation of technology to install early monitoring devices in the region, collaboration on transboundary data, and sustainable infrastructure planning.- Ends
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Download the News18 App to stay updated! tags : climate change Himalayas monsoon rain Uttarakhand Uttarkashi view comments Location : New Delhi, India, India First Published: August 07, 2025, 08:00 IST News india Uttarkashi Is A Wake-Up Call: Experts Warn Climate Crisis Is Making Disasters Alarmingly Frequent Disclaimer: Comments reflect users' views, not News18's. Please keep discussions respectful and constructive. Abusive, defamatory, or illegal comments will be removed. News18 may disable any comment at its discretion. By posting, you agree to our Terms of Use and Privacy Policy.
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