Why in news?

The recent floods along the Trishuli River in Nepal have put the Himalayas' melting glaciers back in focus.

But the damage from a warming Himalaya is not only sudden disasters. It is also a slow economic drain as glaciers retreat, water supplies grow unreliable and rivers that sustain agriculture, industry, cities and hydropower change course.

A new report puts a number on this dependence: more than one-fifth of India's GDP is underpinned by the Himalayas.

What’s in Today’s Article?

• The Report
• The 21.5 Per Cent Figure
• Why Glaciers Matter to the Economy?
• Understanding "Peak Water"
• The Himalayas as a Disaster Hotspot
• The Black Carbon Connection
• The Brick Kiln Solution
• Beyond Brick Kilns

The Report

• The report, "A Resilient Himalaya: Protecting a Region at Risk and Securing Future Prosperity", was compiled by the global consultancy Systemiq in partnership with the Integrated Mountain Initiative.
• It was supported by the International Centre for Integrated Mountain Development (ICIMOD), Nepal, and the GB Pant National Institute of Himalayan Environment, Uttarakhand.

The 21.5 Per Cent Figure

• The report estimates that Rs 64.8 lakh crore, or 21.5 per cent of India's FY24 GDP, depends on the Himalayas. This does not mean glacier melt would erase 21.5 per cent of GDP.
• The figure measures economic activity traceable to Himalayan water, not projected climate damage.
• It was calculated in three layers:
  • Direct: Gross State Domestic Product of Himalayan states.
  • Indirect: Downstream agriculture, manufacturing, hydropower and services that rely on Himalayan-fed rivers and groundwater recharge (rain-fed production excluded).
  • Induced: Supply-chain effects (such as tractors sold from southern states to the Indo-Gangetic Plains) and wage-spending effects (money spent on food and services).

Why Glaciers Matter to the Economy?

• Glaciers act as natural water stores. They hold water as ice and release meltwater into rivers, especially during the dry season.
• The Himalayas feed the Indus, Ganga and Brahmaputra river systems, which support:
  • Wheat and rice cultivation across the Indo-Gangetic plain
  • Tea in Assam and Bengal
  • Hydropower in the Northeast
  • Pilgrimage economies in downstream towns
• The Gangotri glacier, for instance, is the primary source of the Bhagirathi, which becomes the Ganga.

Understanding "Peak Water"

• As warming accelerates melting, glaciers release extra water into rivers. But this cannot continue forever. Himalayan river basins are expected to reach "Peak Water" around the middle of this century.
• This is the point at which glacier meltwater reaches its maximum. After that, flows begin to decline as the ice reserve shrinks.
• On current trajectories, the Hindu Kush Himalaya could lose up to 80 per cent of its present glacier volume by 2100.

The Himalayas as a Disaster Hotspot

• The Himalayas account for 18 per cent of India's land area but around 35 per cent of its disasters. Disasters trigger a damaging cycle:
  • Food and water insecurity
  • Disrupted supply chains
  • Displacement of people
  • Rising macroeconomic and sovereign-debt pressures
  • Reconstruction spending that leaves less money for future resilience

The Black Carbon Connection

• While much of the damage stems from global warming, the report identifies a local source of emissions India can control quickly: black carbon, the soot produced by incomplete combustion.
• Key findings:
  • Recent modelling attributes about one-third of Himalayan glacier mass loss to South Asian black carbon.
  • Industry, primarily brick kilns, contributes 32–42 per cent of South Asian anthropogenic black carbon deposition across the region.
  • Cutting kiln emissions tackles local air pollution and glacier melt through the same plume.
• When black carbon settles on snow, it darkens the surface. The snow then absorbs more sunlight instead of reflecting it.
• As per the reports, this "snow darkening" effect alone adds about 40 watts per square metre of surface heating across the Himalaya in spring.

The Brick Kiln Solution

• The report proposes a targeted fund to modernise brickmaking by upgrading viable kilns, retiring the worst-performing ones and reducing demand for fired bricks.
• Zigzag kiln technology, which burns fuel more efficiently, cuts black carbon and particulate emissions by roughly 70 per cent and fuel use by 20–30 per cent.
• But adoption is uneven:
  • Punjab and Haryana have completed the switch to zigzag kilns.
  • Uttar Pradesh, India's largest brick producer, is at only 56 per cent.
  • The rest of India still runs on traditional technology.

Beyond Brick Kilns

• Experts caution that kilns are not the whole story.
• Real progress requires tackling kilns, cookstoves, transport and crop-residue burning together, coordinated at the airshed scale rather than kiln by kiln or city by city.

Conclusion

The Himalayas are both a water tower and a disaster hotspot for India, underpinning over a fifth of its GDP. With "peak water" approaching mid-century and glacier loss of up to 80 per cent possible by 2100, the threat is structural.

While global warming needs global action, black carbon from brick kilns is a lever India can pull now, with immediate gains for both air quality and glacier health.