Glacial Lake Outburst Flood (GLOF)

Glacial Lake Outburst Flood (GLOF) : Recently, India has launched a national programme to monitor and mitigate Glacial Lake Outburst Flood (GLOF) risks by focusing on 195 high-risk lakes in the Himalayan region amid rising climate-induced disasters.

• Key Highlights : NDMA has shifted from post-disaster response to proactive risk reduction through its Committee on Disaster Risk Reduction (CoDRR).

o Programme likely to scale up after the 16th Finance Commission (FY2027–FY2031) recommendations.

o Objectives of the Programme : Hazard assessment of each at-risk glacial lake.

- Installation of Automated Weather and Water Stations (AWWS) for real-time monitoring.

- Deployment of Early Warning Systems (EWS) downstream.

- Mitigation infrastructure, including water drawdown systems & retention structures.

- Community engagement for awareness and involvement in risk mitigation.

• About GLOF: Disaster events caused by the sudden release of water from glacial lakes.

o This abrupt discharge often leads to catastrophic flooding in downstream areas.

o Glacial Lakes: Formed when melting glaciers leave behind depressions filled with meltwater.

- These lakes may occur: In front of glaciers (proglacial), On top of glaciers (supraglacial), Or beneath glaciers (subglacial).

- They are typically dammed by unstable ice, loose sediment, or moraine (rock and debris).

• How Do Glacial Lakes Become Hazardous: As glaciers recede due to climate change, these lakes expand in size.

o Larger lakes under unstable conditions pose higher risks of bursting.

o If the natural dam fails, a massive volume of water can rush downhill, causing destructive floods.