China drought tied to pollution

Air pollution in China’s industrial east appears to have significantly reduced light rainfall over the last 50 years, raising the possibility that cutting pollution could ease a severe drought in the region, according to a study released Saturday.

Light rain -- anything from a drizzle to 0.4 of an inch in a day -- is also crucial for agriculture, as opposed to heavy rain, which triggers floods that can wash away crops.

Researchers from the U.S. Department of Energy’s Pacific Northwest National Laboratory found that the number of days of light rainfall in eastern China decreased by 23% from 1956 to 2005 because of air pollution.

“Besides the health effects, acid rain and other problems that pollution creates, this work suggests that reducing air pollution might help ease the drought in north China,” lead researcher Yun Qian said.

China suffers from an uneven distribution of its water resources. Weather patterns create an arid north and flood-prone south, costing the government tens of millions of dollars in lost productivity each year. Parts of China’s wheat-growing northern regions are currently suffering their worst drought in five decades.

The study could also help further the understanding of how aerosols -- tiny air particles caused naturally and by human activities such as burning fossil fuels -- affect the formation of rain clouds, researchers said. The study was published in the Journal of Geophysical Research.