Aerosols and the darkening of the Himalayan glaciers
In the Himalayas, the impact of black carbon on melting snowpack and glaciers may be equal to that of CO2. Warmer air resulting from the presence of black carbon in South and East Asia over the Himalayas contributes to a warming of approximately 0.6 °C. A summer aerosol sampling on a glacier saddle of Mt. Everest (Qomolangma) in 2003 showed industrially induced sulfate from South Asia may cross over the highly elevated Himalaya. This indicated BC in South Asia could also have the same transport mode. And such kind of signal might have been detected in at a BC monitoring site in the hinterland of Tibet. Snow sampling and measurement suggested BC deposited in some Himalayan glaciers may reduce the surface albedo by 0.01-0.02. BC record based on a shallow ice core drilled from the East Rongbuk glacier showed a dramatic increasing trend of BC concentrations in the ice stratigraphy since the 1990s, and simulated average radiative forcing caused by BC was nearly 2 W m−2 in 2002. This large warming trend is the proposed causal factor for the accelerating retreat of Himalayan glaciers, which threatens fresh water supplies and food security in China and India. A general darkening trend in the mid-Himalaya glaciers revealed by MODIS data since 2000 could be partially attributed to black carbon and light absorbing impurities like dust in the springtime.
——Wikipedia & NASA
——Wikipedia & NASA