Moraine-Dammed Lakes in Himachal Pradesh and the Trans Himalayan Region of Tibet

• Glacial Retreat: Rapid reduction in glacier sizes due to changing weather patterns has led to an increase in moraine-dammed lakes in Himachal Pradesh and the Trans Himalayan Region of Tibet.
• Potential Threat: These lakes pose a significant risk to human life and infrastructure downstream if they burst, leading to potential disasters.

Key Findings:

• Satluj River Catchment Area:
  • The number of glacial lakes increased from 562 in 2019 to 1,048 in 2023, according to satellite data analyzed by the Centre on Climate Change of the Himachal Pradesh Council for Science Technology-Environment (HIMCOSTE).
  • The study area covers the catchment area of the Satluj basin, from Jhakri to the Mansarovar Lake in Tibet, where the river originates.
• Lake Distribution by Size (2023):
  • Small Lakes: 900 lakes, each less than 5 hectares in size.
  • Medium Lakes: 89 lakes, each between 5 to 10 hectares.
  • Large Lakes: 59 lakes, each larger than 10 hectares.

Climate Impact:

• Increase in Small Lakes: The rise in the number of smaller lakes (<5 hectares) indicates significant climate warming effects, especially in the higher Himalayan region.
  • Reasons: Swift melting of glaciers and reduced snowfall during winter are contributing factors.
• Regional Analysis:
  • Tibetan Himalayan Region (Upper Satluj Basin): Higher susceptibility to glacial lake formations compared to Spiti and Lower Satluj basins.
  • Temperature Rise: Average temperatures in high-altitude areas are rising faster than in lower areas, contributing to the formation of more lakes in the upper regions.

Downstream Risks:

• Potential Disasters:
  • The rise in glacial lakes could be disastrous if they burst due to increased water volume, calving of adjoining glaciers, or avalanches of snow/rocks.
  • Impact: Depending on the outburst’s volume, velocity, and spread, the resulting floods could threaten habitations and infrastructure downstream.

Important Points for UPSC:

• Focus on the impact of climate change on glacial retreat and the formation of moraine-dammed lakes.
• Understand the geographical distribution and potential risks associated with the increase in glacial lakes, especially in the Satluj river catchment area.
• Be aware of the implications for disaster management and the need for monitoring and mitigation strategies in the Himalayan region.

MCQs with answer and Explanations 

1. Which of the following regions has seen a significant increase in the number of moraine-dammed lakes due to rapid glacial retreat?

A) Western Ghats

B) Eastern Himalayas

C) Himachal Pradesh and the Trans Himalayan Region of Tibet

D) Nilgiri Hills

Answer: C) Himachal Pradesh and the Trans Himalayan Region of Tibet

Explanation: The rapid reduction in glacier sizes in Himachal Pradesh and the Trans Himalayan Region of Tibet has led to a significant increase in the number of moraine-dammed lakes, posing a potential threat to downstream areas.

2. According to recent satellite data, how many glacial lakes were identified in the Satluj River catchment area in 2023?

A) 562

B) 900

C) 1,048

D) 2,048

Answer: C) 1,048

Explanation: The number of glacial lakes in the Satluj river catchment area almost doubled from 562 in 2019 to 1,048 in 2023, as revealed by satellite data.

3. Which size category of glacial lakes has seen a notable increase, indicating significant climate warming effects in the higher Himalayan region?

A) Lakes smaller than 5 hectares

B) Lakes between 5 and 10 hectares

C) Lakes larger than 10 hectares

D) Lakes larger than 20 hectares

Answer: A) Lakes smaller than 5 hectares

Explanation: The increase in the number of small lakes (less than 5 hectares) indicates that climate warming effects are more significant in the higher Himalayan region.

4. Which part of the Satluj basin is more susceptible to the formation of glacial lakes, according to the study?

A) Lower Satluj basin

B) Spiti basin

C) Upper Satluj basin (Tibetan Himalayan Region)

D) All regions equally

Answer: C) Upper Satluj basin (Tibetan Himalayan Region)

Explanation: The study indicates that the Upper Satluj basin, particularly in the Tibetan Himalayan Region, is more susceptible to the formation of glacial lakes compared to the Spiti and Lower Satluj basins.

5. What is one of the main dangers posed by the increase in glacial lakes in Himachal Pradesh and the Trans Himalayan Region of Tibet?

A) Water scarcity

B) Increased agricultural productivity

C) Potential outburst floods

D) Earthquakes

Answer: C) Potential outburst floods

Explanation: The increase in glacial lakes can be dangerous if these lakes burst, leading to outburst floods that can threaten downstream habitations and infrastructure.

UPSC Mains questions

1. “The rise in moraine-dammed lakes in the higher Himalayan region poses significant risks to downstream populations and infrastructure.” Discuss in the context of recent studies highlighting climate change impacts in Himachal Pradesh and the Trans Himalayan Region of Tibet.

2. Examine the implications of the increasing number of glacial lakes in the Satluj river catchment area for disaster management and planning in the region. What steps should be taken to mitigate potential hazards associated with glacial lake outburst floods (GLOFs)?

3. Critically analyze the role of climate change in the formation of moraine-dammed lakes in the Himalayas. How does this phenomenon reflect broader environmental challenges in high-altitude regions?

4. Discuss the significance of satellite-based monitoring in understanding the formation and risks associated with glacial lakes in the Himalayan region. How can this data be utilized to enhance early warning systems and disaster preparedness?

5. “The rapid melting of glaciers and the formation of small glacial lakes in the Trans Himalayan Region indicate a greater climate change impact in higher altitudes.” Evaluate this statement with reference to recent climatic trends and their implications for the environment and local communities.