Soot(烟灰) and Snow: a Hot Combination
【*】New research from NASA scientists suggests emissions (释放) of black soot alter the way sunlight reflects off snow.
According to a computer simulation(模拟), black soot may be responsible for 25 percent of observed global warming over
the past century.
【*】Soot in areas with snow and ice may play an important role in climate change. Also, if snow and ice covered areas begin melting, the warming effect increases, as the soot becomes more concentrated on the snow surface. This provides a positive feedback, as glaciers and ice sheet smelt, they tend to get even dirtier,"said Dr.James Hansen, a researcher at NASA's
Goddard Institute for Space Studies, New York.
【*】Hansen found soot's effect on snow albedo(反照率)( solar energy reflected back to space), which may be contributing
to trends toward early springs in the Northern Hemisphere, such as thinning Arctic sea ice, melting glaciers and permafrost(永冻层). Soot also is believed to play a role in changes in the atmosphere above the oceans and land.
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Soot's Role in Climate Changes Above Oceans and Land
Observations of Warming in the Northern Hemisphere
Explanation of Increased Warming Effect Caused by Soot
Black Soot in Snow and Icy Areas Leading to Climate Change
Black Soot Contributing to Global Warming
Greenhouse Gases as the Main Factor of Global Warming
