Context:
According to a study, black carbon aerosols have had an indirect impact on the mass increase of Tibetan Plateau glaciers by altering the long-range transport of water vapor from the South Asian monsoon region.
Relevance:
GS III: Environment and Ecology
Dimensions of the Article:
- About Black Carbon (BC) aerosols
- Impact on glaciers melting
About Black Carbon (BC) aerosols
- Black Carbon (BC) aerosols, also known as soot, are tiny particles that are released into the atmosphere through incomplete combustion processes, both human (such as diesel engines) and natural (such as wildfires).
- BC absorbs visible and infrared radiation, which can cause the atmosphere to heat up and darken surfaces like snow and ice.
- These effects can have significant impacts on the climate and climate change, as well as negative effects on human health.
- Unlike long-lived greenhouse gases like carbon dioxide, BC only remains in the atmosphere for about 1-2 weeks, so its impacts tend to be more regional rather than global.
Deposition over Himalayas
- The area surrounding the Tibetan Plateau in South Asia has some of the highest levels of black carbon emissions in the world.
- Several studies have shown that black carbon aerosols from South Asia can be transported over the Himalayas to the inland region of the Tibetan Plateau.
Impact on glaciers melting
- Black carbon deposited on snow decreases the albedo, or the amount of solar radiation reflected, of the surface, which speeds up the melting of glaciers and snow cover.
- This changes the hydrological process and water resources in the region.
- Black carbon also heats up the middle and upper atmosphere, increasing the North-South temperature gradient.
- As a result, monsoon season precipitation in the central and southern Tibetan Plateau decreases, particularly in the southern region.
- This decrease in precipitation leads to a decrease in the mass gain of glaciers. From 2007 to 2016, the reduced mass gain due to decreased precipitation accounted for 11% of the average glacier mass loss on the Tibetan Plateau and 22.1% in the Himalayas.
-Source: Down to Earth
