GLACIAL LAKE OUTBURST FLOODS (GLOFs)

Current Context : Recent flash floods in Nepal’s Lende River have highlighted the rising dangers of Glacial Lake Outburst Floods (GLOFs) in the Himalayan region.

 ABOUT GLOFs (GLACIAL LAKE OUTBURST FLOODS)

Definition: A GLOF is the sudden release of water from a glacial lake formed due to melting glaciers. Example: South Lhonak GLOF in 2023 in Sikkim

Types of Glacial Lakes

1. Supraglacial Lakes:

• Formed on top of glaciers
• Melt rapidly during summer
  2. Moraine-Dammed Lakes:
• Formed at the toe of glaciers
• Held by loose rocks or ice; more prone to sudden outbursts

WHY GLOFs ARE INCREASING IN INDIA ?

• Main Triggers:
  • Around two-thirds of GLOFs are caused by ice avalanches or landslides
  • Others are due to:
    • Weak moraine dams (e.g., Chorabari GLOF in 2013, Uttarakhand)
    • Earthquakes
  • Climate Change Effects:
  • 2023 and 2024 were the hottest years globally
  • Higher temperatures = Faster glacier melting = More lake formation
  • Monitoring Challenges:
  • 7,500 lakes lie above 4,500 metres
  • Tough terrain and short summer windows make them hard to track