That's according to new NASA research published in the October issue of the American Meteorological Society s Journal of Climate. Heating and cooling of the Earth are influenced by cloud cover.
Clouds can act as a natural sun shield by reflecting light back into space.
But clouds can also coat the skies like a blanket, trapping warmth. Precisely how these competing attributes will change in response to a warmer atmosphere is not well understood. Anthony Del Genio of NASA s Goddard Institute for Space Studies in New York, analyzed three years of observations of low clouds over land, a type of cloud thought likely to contribute to future cooling. Some climate theories predict that a warmer atmosphere would evaporate more water, and this additional water vapor would form thicker clouds. However, Del Genio s research found that when air temperatures were higher, clouds were thinner and thus less capable of reflecting sunlight.