Highlighting the geographical and economic importance of the Hindukush-Himalayan region, outline the changes in the critical geographical features and the consequence it will have.

The Hindukush-Himalayan region consists of the central Asian and south Asian alpine regions. It plays a very important role in the geography and economy of the region:

• It is the third largest source of fresh water in form of glaciers, after the Arctic and Antarctica. Also called the third pole for the same reason.
• It plays an important role in increasing the albedo of the earth because white snow reflects most of the sunlight. Hence, it helps in reducing the temperature.
• The glaciers and ice caps of these mountains provide water to countries of South Asia including Nepal, India, Pakistan, Bhutan, Bangladesh, etc.
• It helps in sustaining the agrarian economy and drinking water needs.
• These mountains act as barriers against cold polar winds from the north, hence, helping in maintaining the tropical climate.
• Governs the climate of the Indian subcontinent.
• It is one of the biodiversity hotspots of the world.
• Important for hydroelectric power generation.
• Important for tourism economy.

However, the critical geographical features are undergoing rapid changes:

• Increased global warming. These are the fastest melting permanent ice caps, estimated to completely melt by 2050.
• Deposition of black carbon (soot) from the burning of fossil fuels leads to a decrease in the albedo. Hence more heat is absorbed and this becomes a domino effect.
• Biodiversity loss due to human population pressure, deforestation, etc.

Consequences:

• Himalayan rivers are the lifeline of the agrarian economy and food security of the region. Drying up of rivers due to the melting of glaciers will have catastrophic consequences.
• It will further deteriorate the problem of drinking water shortage.
• The rise in sea level and submergence of islands and coastal areas.
• Effects of biodiversity loss on food chain and ecology.
• Loss of livelihood of those engaged in tourism.
• Glacial outburst floods and extreme climatic conditions.
• Flooding and sedimentation in rivers.