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Himalayan Glacial Lakes Expand by 10.81% in 13 Years, Pose Flood Risks
Context:
The Himalayan region has seen an increase in the area of glacial lakes and other water bodies, growing by 10.81% between 2011 and 2024.
- This expansion raises concerns about the risk of floods caused by the bursting of these lakes. Such floods occur when the natural barriers of the lakes break, releasing large volumes of water.
- A report by the Central Water Commission (CWC) has highlighted this alarming trend.
Key Findings from the Report
- Increase in Lake Area: Due to climate change, the total area of glacial lakes and water bodies in the Himalayan region has increased from 533,401 hectares in 2011 to 591,108 hectares in 2024.
- Impact on Rivers: This expansion could significantly affect the water flow in major rivers like the Ganga, Brahmaputra, and Indus.
Growing Threat of GLOFs
- Increased Frequency of Events: Data from the International Centre for Integrated Mountain Development (ICIMOD) shows over 70% of the 700 recorded GLOF events since 1833 occurred in the past 50 years.
- The highest number of GLOF incidents occurred in 1980 (15 events), followed by 2015 (13 events).
- Other notable years include 1973, 1974, 2002, and 2010, each with 10 incidents.
- Triggers for GLOFs: ICIMOD identifies mass movements (avalanches and landslides) as the primary trigger for 54% of GLOF events.
- Extreme rainfall accounted for 18% of the incidents.
Human and Environmental Impact:
- Since 1833, GLOFs have caused over 7,000 fatalities in the Hindu Kush Himalayan region.
- These events threaten lives, infrastructure, and ecosystems downstream.
Threats to Neighboring Countries: The report also highlights the potential risks to neighboring countries like Bhutan, Nepal, and China, which share river systems originating in the Himalayas.
- It recommends collaborative efforts with these countries to monitor, share data, and plan for potential floods. Suggestions include:
- Early Warning Systems: Developing and implementing early warning mechanisms.
- Disaster Management Plans: Enhancing disaster response strategies.
- Community Awareness: Promoting awareness initiatives to safeguard vulnerable populations.
- Glacial Retreat and Lake Expansion: The primary reason for the expansion of these lakes is the rapid melting of glaciers, driven by rising temperatures.
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- This change poses risks to:
- Communities living in lower areas.
- Infrastructure and biodiversity.
- Wildlife in the region.
- The retreat of glaciers and the growth of lakes are clear indicators of climate change. The CWC is developing advanced technologies to identify and mitigate risks effectively.
Importance of Monitoring: The CWC emphasises the critical need to monitor these lakes closely.
- Advanced satellite technologies, such as Sentinel-1 Synthetic Aperture Radar (SAR) and Sentinel-2 Multispectral Imagery, are being used to detect changes in lake sizes with 10-meter accuracy, even under cloudy conditions.
- These technologies can provide timely warnings to mitigate disasters.
NGT’s Intervention: The National Green Tribunal (NGT) has taken suo moto cognisance of the issue, issuing notices to the central government and other relevant bodies.
- Growth of Glacial Lakes: The NGT noted a 33.7% increase in the surface area of glacial lakes in India between 2011 and 2024.
- High-Risk Lakes Identified: Sixty-seven lakes have shown over 40% surface expansion and are classified as high-risk for Glacial Lake Outburst Floods (GLOFs).
- These lakes are primarily located in Ladakh, Himachal Pradesh, Uttarakhand, Sikkim, and Arunachal Pradesh.
Potential Hazards and Recommendations: The NGT has highlighted the risk of sudden floods caused by the bursting of these lakes, which could devastate communities, infrastructure, and biodiversity. Recommendations include:
- Enhanced Monitoring: Increasing surveillance of glacial lakes.
- Flood Management Strategies: Improving flood management and early warning systems.
- Legal Compliance: Addressing violations under biodiversity, water pollution, and environmental protection laws.
- Government Accountability: The NGT has issued notices to the Ministry of Environment, Forest and Climate Change, the Director of the GB Pant Himalayan Institute, and the Central Pollution Control Board. These bodies are required to respond by March 10, ahead of the next hearing.
