Slowing the Great Himalayan Glacier Melt

Curbing Air Pollution remains the Key to battling this growing global threat

By Tandin Wangchuk

Black carbon deposits originating from factories, cooking and vehicles are compounding the effects of climate change to speed up the melting of the Himalayan glaciers.

Further, more aggressively curbing black carbon emissions can slow glacier melt and improve the security of water resources in the region. These are according to a new World Bank report.

Current policies in place to reduce black carbon emissions – through enhancing fuel-efficiency standards, phasing out diesel vehicles and promoting electric cars – while laudable, will still reduce black carbon deposits by only 23 percent, not enough to prevent an acceleration of water releases from glacier melt in the region.

However, new economically and technically feasible policies are within reach to contain glacier melt at current levels.

For example, improving the efficiency of brick kilns, which account for roughly half of black carbon emissions, would reduce melt-accelerating deposits, and modest up-front investments that would quickly pay off are available.

Cleaner cookstoves and cleaner fuels are another key way to reduce black carbon emissions. Incentivizing households to switch from biomass or coal to liquefied petroleum gas (LPG), and, in the long run, to solar energy could achieve this.

“Recent devastating flash floods attributed to a collapsing glacier in the Himalayas were a sobering reminder of the sometimes disastrous effects of climate change and the dangers we have to protect against,” said Hartwig Schafer, World Bank Vice President for South Asia.

“As glaciers shrink, the lives and livelihoods of many people downstream are affected by changes in the water supply. We can slow glacier melt by collectively acting to curb the black carbon deposits that are speeding the thinning of the ice. Regional cooperation to protect these resources will pay important dividends for the health and well-being of the people in the region,” he said.

The mountain ranges of the Himalayas, the Hindu Kush, and the Karakoram span 2,400 kilometers across six nations and contain 60,000 km² of ice – storing more water than anywhere besides the Arctic and Antarctic.

Melting glaciers and loss of seasonal snow pose significant risks not just to the people who live at their foot but to the stability of water resources in the South Asia region more broadly. The impacts will only get worse unless greater efforts are made to curb black carbon deposits that are accelerating melting.

More than 750 million people depend on the glacier- and snow-fed Indus, Ganges, and Brahmaputra rivers for freshwater, and changes in the volume and timing of flows will have important economic and social implications. By 2050, from 1.5 billion to 1.7 billion people in South Asia are projected to be vulnerable to water scarcity.

Glaciers of the Himalayas finds that in addition to changing temperatures and precipitation patterns, black carbon deposits – air-borne particles generated by incomplete combustion from brick kilns, diesel exhaust, and the burning of biomass – are accelerating glacier and snow melt in these ranges. Business-as-usual practices would further speed glacier melt, with harmful implications for the health and well-being of people in the region.

Finally, countries in South Asia must work together to manage hydropower resources, an important source for the region’s clean energy needs and a generator of energy trade and security. Unstable water flow from glacier melt and more variable precipitation underscore the need to stabilize availability over the longer term to make hydropower more viable.

Fully addressing the challenges associated with the melting glaciers of the Himalayas is a transboundary task that goes beyond the scope of a single country’s policymakers. Regional cooperation will be necessary to create joint adaptation strategies. A first step could be sharing information about the evolving state of glaciers and risks associated with it.

“Water resource management policies must evolve because the trends we are observing point to a different and more challenging future,” said MuthukumaraMani, lead economist in the World Bank’s South Asia region and a lead author of the report. “Success will require an active and agile cooperation between researchers and policymakers so both groups can continue to learn about the problems at hand.”

Research for the report received support from the South Asia Water Initiative, a trust fund supported by the United Kingdom’s Foreign, Commonwealth and Development Office, Australia’s Department of Foreign Affairs, and Norway.

Experts say that the recent glacial lake disaster in Utterkhand, India underscores the fragility of the Himalayan mountains where the lives of millions are being altered by climate change.

A 2019 report by the International Centre for Integrated Mountain Development found that even if the world was to meet its most ambitious climate change goals, rising temperatures would melt a third of the Himalayan glaciers away by the end of the century.

Himalayan glaciers are melting twice as fast since 2000 as they were in the 25 years before due to human-caused climate change, a 2019 paper published in the journal Science Advances found.

Whether this particular disaster was caused by climate change is not known. But climate change can increase landslides and avalanches.

As glaciers melt due to warming, valleys that were earlier crammed with ice open up, creating space for landslides to move into. In other places, steep mountainous slopes may be partially “glued” together by ice frozen tightly inside its crevices.

Development plans need to “go along with the environment” and not against it, said Anjal Prakash, a professor at the Indian School of Business who has contributed to research into the impacts of climate change in the Himalayas for the Intergovernmental Panel on Climate Change.

“Climate change is here and now. It is not something that is going to happen later on.”

Bhutan has a total of 700 glaciers according to the 2018 Bhutan Glacier Inventory released by the National Center for Hydrology and Meteorology (NCHM), recently. The new study says the glaciers cover an area of about 630 square kilometres or 1.64% of the country’s total land area.

Thorthormi glacier in Lunana is one of the 341 glaciers in the Punatsang Chhu basin. The Punatshang Chhu basin consists of three sub-basins namely Pho Chhu, Mo Chhu and Dang Chhu sub-basin.

As per the study, Dang Chhu sub-basin has no glacier contributing to the river system, but the other two combined has the highest number of glaciers in Bhutan.

The other river basins are Wang Chu basin, which consists of Thim Chhu, Pa Chhu, and Haa Chhu, and Manas Basin consisting of Drangme Chhu, Mangde Chhu, Kuri Chhu, and Chamkhar Chhu sub-basins.

Among the three river basins, Wang Chhu basin has the lowest number of glaciers at 47. The Manas Chhu basin has 312 glaciers. The largest glacier, which is almost 16 kilometres long, lies at the base of Gangkar Phuensum in the Mangde Chhu sub-basin.

 However, figures maintained by the Glacier Area Mapping for Discharge in High Asia Mountains (GAMDAM) in 2015 and International Center for Integrated Mountain Development(ICIMOD) in 2014 vary.

The current study by the NCHM saw a significant decrease both in terms of number and area size of glaciers in the country.

 The study attributed such variation in number and area size to the inclusion of snow cover on steep slopes as separate glaciers, the inclusion of seasonal snow-covered lakes as glaciers, and use of improved satellite images by the previous reports.