Haze Over China May Be Deflecting Sun’s Rays

China’s skies have darkened over the last 50 years, possibly due to haze from a ninefold increase in fossil fuel emissions, according to researchers from the U.S. Department of Energy.

The researchers, writing in this month’s edition of Geophysical Research Letters, found that the amount of solar radiation measured at more than 500 stations in China fell from 1954 to 2001 despite a decrease in cloud cover.

“The pollution [that] resulted from human activity may have created a haze which absorbs and deflects the sun’s rays,” said the study’s lead author, Yun Qian of the Energy department’s Pacific Northwest National Laboratory in Washington state.

The researchers found the amount of sunlight hitting the ground had fallen by 3.7 watts per square yard in each of the last five decades.