Aerosols such as black carbon and dust particles seem to have a greater effect on the Tibetan Plateau's snow than does anthropogenic climate change.

Yun Qian of the Pacific Northwest National Laboratory in Richland, Washington, and his colleagues simulated the impact of carbon dioxide and aerosols on the snowpack using a global climate model. They found that the deposition of black carbon on snow increases the surface air temperature by an average of 1° C across the plateau because it boosts the absorption of sunlight. From April to July, black carbon is up to four times more effective at melting snowpack per degree of warming it induces than is air warming from increased atmospheric carbon dioxide.

Aerosols have a larger effect on the Tibetan Plateau (pictured) than on any other snow-covered region in the world, producing earlier snowmelt and affecting monsoon trends, the authors report.

Credit: TAO IMAGES/ALAMY

Atmos. Chem. Phys. 11, 1929–1948 (2011)