Context: A new research by World Bank (WB) is released recently titled “Glaciers of the Himalayas, Climate Change, Black Carbon and Regional Resilience”.
Key highlights of the research

• The research covers the Himalaya, Karakoram and Hindu Kush (HKHK) mountain ranges, where glaciers are melting faster than the global average ice mass.
• The rate of retreat of HKHK glaciers is estimated to be 0.3 metres per year in the west to 1.0 metre per year in the east. BC adds to the impact of climate change.
• The glaciers in the HKHK mountains contain estimated ice reserves of 163 cubic kilometres, of which almost 80% feeds the Indus, the Ganges and the Brahmaputra.
• Black carbon (BC) deposits produced by human activity which accelerate the pace of glacier and snow melt in the Himalayan region can be sharply reduced through new, currently feasible policies by an additional 50% from current level.
• Full implementation of current policies to mitigate BC can achieve a 23% reduction.
• Policy measures to cut BC emissions are enhancing fuel efficiency standards for vehicles, phasing out diesel vehicles and promoting electric vehicles, accelerating the use of liquefied petroleum gas for cooking and through clean cookstove programmes, as well as upgrading brick kiln technologies.

Deposits of BC act in two ways hastening the pace of glacier melt

• By decreasing surface reflectance of sunlight
• By raising air temperature
• Industry [primarily brick kilns] and residential burning of solid fuel together account for 45–66% of regional anthropogenic [man-made] BC deposition, followed by on-road diesel fuels (7–18%) and open burning (less than 3% in all seasons)” in the region.

What is Black Carbon?

• Black carbon, or soot, is part of fine particulate air pollution (PM2.5) and contributes to climate change.
• Black carbon is formed by the incomplete combustion of fossil fuels, wood and other fuels.
• Complete combustion would turn all carbon in the fuel into carbon dioxide (CO2), but combustion is never complete and CO2, carbon monoxide, volatile organic compounds, and organic carbon and black carbon particles are all formed in the process.
• The complex mixture of particulate matter resulting from incomplete combustion is often referred to as soot.
• Black carbon is a short-lived climate pollutant with a lifetime of only days to weeks after release in the atmosphere.
• During this short period of time, black carbon can have significant direct and indirect impacts on the climate, the cryosphere (snow and ice), agriculture and human health.
• Black carbon is always co-emitted with other particles and gases, some of which have a cooling effect on the climate.