Context

• The National Green Tribunal (NGT) has taken suo motu cognizance of a news report which stated that glacial lakes have increased by about 10.81% in the last 13 years due to rising temperatures.

Formation of Glacial Lakes

• Glacial Retreat: As glaciers melt and retreat, they leave behind depressions in the landscape.
• Water Accumulation: Meltwater from the glacier fills these depressions, forming lakes.
• Moraine Dams: Sometimes, glacial debris, known as moraine, can form natural dams, trapping water and creating larger lakes.

The Impact of Glacial Lakes

Positive Impacts:

• Water Resource: Glacial lakes can serve as important water sources, particularly in regions with water scarcity.
• Biodiversity: These lakes can support unique ecosystems, providing habitats for various aquatic species.
• Tourism: The scenic beauty of glacial lakes can attract tourists, boosting local economies.

Negative Impacts:

• Glacial Lake Outburst Floods (GLOFs): As glaciers retreat, they can form unstable moraine dams. If these dams breach, they can release massive amounts of water, causing devastating floods downstream.
• Climate Change Acceleration: Darker water bodies like glacial lakes absorb more solar radiation, leading to increased melting of surrounding ice and snow, further accelerating climate change.
• Infrastructure Damage: GLOFs can damage infrastructure, including roads, bridges, and power plants, causing significant economic loss.
• Loss of Life: In extreme cases, GLOFs can lead to loss of life and displacement of communities.

examples

• Lake Louise, Canada: A stunningly beautiful lake nestled in the Canadian Rockies.
• Lake Tahoe, USA: A large freshwater lake located in the Sierra Nevada mountains.
• The Great Lakes of North America: Formed by glacial activity during the last Ice Age.