Arunachal loses 110 Glaciers in 32 years

A recent study has revealed that the eastern Himalayas in Arunachal Pradesh have lost 110 glaciers over a span of 32 years (1988-2020).

Key Findings of the Study

• The study, conducted by researchers from Nagaland University and Cotton University, used remote sensing and GIS technology to track glacier boundaries.
• The number of glaciers in Arunachal Pradesh decreased from 756 to 646 during the study period.
• The total glacial cover shrank from 585.23 sq. km to 309.85 sq. km, a loss of more than 47%.
• Most glaciers are located at an elevation of 4,500–4,800 metres, are north-facing, and lie on slopes of 15°–35°.
• This rapid glacial loss has exposed bedrock and created glacial lakes, raising the risk of glacial lake outburst floods (GLOFs).

Enroll now for UPSC Online Course

What is Glacial Retreat?

• Glacial retreat refers to the process where glaciers shrink as their ice melts faster than new snow accumulates. 
• It is a key indicator of global climate change and is occurring at an alarming rate worldwide, especially in high-altitude regions like the Himalayas.

Causes of Glacial Retreat

• Climate Change: Rising global temperatures lead to increased ice melting, surpassing snow accumulation.
• Changes in Precipitation Patterns: Erratic snowfall and reduced winter precipitation slow down glacial growth.
• Black Carbon Deposition: Pollutants from human activities settle on glaciers, absorbing more heat and accelerating melting.
• Geological Factors: Slope, altitude, and rock type influence how glaciers respond to warming.

Himalayas under threat

• The Himalayas, often called the ‘Third Pole’, hold the largest collection of glaciers outside the polar regions. 
  • These glaciers are a crucial freshwater source for over 1.3 billion people in downstream regions.
• Climate studies show that the Himalayas have witnessed a temperature rise of 1.6°C over the past century. 
• The eastern Himalayas, in particular, are warming at a rate higher than the global average, with temperatures increasing by 0.1° to 0.8°C per decade. 
• By the end of the century, the region could see a 5-6°C temperature rise and 20-30% more precipitation.

Check Out UPSC Modules From PW Store

Impact of Glacial Retreat

• Freshwater Crisis: The retreating glaciers will severely affect water availability and distribution, impacting agriculture and drinking water supplies.
• Increased GLOF Risk: The formation of glacial lakes increases the chances of catastrophic floods, as seen in the 2023 Sikkim disaster that killed at least 55 people and destroyed a 1,200 MW hydropower project.
• Ecosystem Disruptions: Changes in temperature and precipitation patterns could destabilize ecosystems and impact biodiversity.

Ready to boost your UPSC 2025 preparation? Join PW’s UPSC online courses today!