After a decade of decline, worldwide sulfur emissions increased between 2000 and 2005, driven by growth in developing economies, a U.S. study says.

A collaborative study by the U.S. Department of Energy's Pacific Northwest National Laboratory in Richland, Wash., and the University of Maryland, found that manmade sulfur dioxide emissions by the historically large emitters — Europe and the United States — showed a decline, but levels began to rise again in 2000 due largely to international shipping and a growing Chinese economy, a PNNL release said Monday.

"Sulfur dioxide is an important component of the atmosphere," says lead author Steven Smith of the Joint Global Change Research Institute in College Park, Md. "It changes the radiative balance of the earth by influencing the amount of the sun's energy that warms the globe. We need to understand how much sulfur dioxide is emitted, and when and where it is emitted. This study will help us do that."

The Industrial Revolution brought widespread combustion activities that spew sulfur into the atmosphere, with the potential to acidify rain, soil and lakes, and it can counteract some of the warming effect of carbon dioxide, making it an important component of the environment to understand, researchers said.

Much of the recent increase in levels can be laid at the door of China and its phenomenal growth, they said.

By 2005, China's share of sulfur emissions accounted for 28 percent of the global total, up from just 2 percent in 1950, they reported.

The international shipping industry generally uses a lower quality, higher sulfur content fuel than other transportation modes, and emissions from this activity have been growing, the study found, now making up 10 percent of the global total.

Share This Article With Planet Earth