In context of the significance of the Himalayan mountain system for South Asia, explain the factors responsible for melting of glaciers and its impact on the region.

The South Asian Himalayan system is critical for the survival of India, Pakistan, Bangladesh, Nepal and Bhutan.

Factors responsible for glacier melting:

• Global warming has led to increase in average temperature of Earth by over 1^oC since pre-industrial times.
• This change has been more pronounced in Himalayan region.
• Air pollution has also contributed to melting, e.g. deposition of black and brown carbon reduces albedo of glaciers. This increases heat absorbed.

Impact on the region:

• Perennial nature of key rivers like Ganga, Brahmaputra and Indus is threatened.
• This affects viability of agriculture and hydropower generation.
• Increased risk of floods due to accelerated melting of glacial ice. States like Uttarakhand and Himachal Pradesh are vulnerable.
• Glacial lake outburst floods are possible in Uttarakhand and Sikkim. These natural disasters endanger life and property of citizens.
• Risk of disputes over transboundary Himalayan rivers, owing to reduced water flow, e.g. between India and Pakistan over Indus and its tributaries.

Loss of access to water and natural disaster risks make human development difficult. Therefore, climate change mitigation is required to preserve glaciers.