1. Introduction to Glacial Lakes

    - Glacial Lakes, formed through the process of glacier retreat and thinning, are bodies of water in the Himalayan region that have been rapidly escalating since the Industrial Revolution.

    - The categorization of these lakes is based on the method of their formation: Moraine-dammed, Ice-dammed, Erosion and other glacial lakes.

    - Of the known expanding lakes, most are Moraine-dammed, followed by Erosion, other types, and least being the Ice-dammed.

    - These lakes serve as crucial freshwater sources to the rivers in the Himalayas.

2. The 'Third Pole' and its Glacial Sensitivity

    - The Himalayan Mountains, known as the Third Pole due to their vast glaciers and snow cover, are considerably susceptible to global climate changes.

    - The implications of these changes extend beyond physical characteristics and bear profound societal impacts.

3. Associated Risks of Glacial Lakes

    - Glacial lakes pose significant threats, particularly in the form of Glacial Lake Outburst Floods (GLOFs), causing devastating impacts on downstream communities.

    - Such outbursts occur when massive meltwater volumes are released due to the collapse of natural dams made of moraine or ice, leading to catastrophic downstream flooding.

    - These collapses can be initiated due to various factors such as ice or rock avalanches, extreme weather events, and other environmental factors.

4. Monitoring of Glacial Lakes

    - Studying and monitoring the expansion and occurrences of these lakes pose challenges due to the impaired accessibility and rough terrain of the Himalayan region.

5. Recent Study Findings

    - ISRO’s long-term satellite imaginations covering the Indian Himalayan river basin's catchments from 1984 to 2023 depict significant changes in glacial lakes.

    - According to ISRO, out of the 2,431 lakes larger than 10 hectares identified in 2016-17, 676 have notably expanded since 1984.

6. Significance of Recent Study

    - Satellite remote sensing technology serves as a potent tool for inventory and monitoring due to its broad coverage and revisit capability.

    - Assessing long-term changes in glacial lakes is vital to understand glacier retreat rates, evaluate GLOF risks, and gain insights into climate change impacts.

    - The study also aids in formulating strategies for GLOF risk management and climate change adaptation in glacial environments by providing valuable insights into glacial lake dynamics.