COLLEGE PARK, Md. -- A new analysis of sulfur emissions appearing in the journal Atmospheric Chemistry and Physics shows that after declining for a decade, worldwide emissions rose again in 2000 due largely to international shipping and a growing Chinese economy. An accurate read on sulfur emissions will help researchers predict future changes in climate and determine present day effects on the atmosphere, health and the environment.
"Sulfur dioxide is an important component of the atmosphere. 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," said lead author Steven Smith of the Joint Global Change Research Institutein College Park, Md., a collaboration between the Department of Energy's Pacific Northwest National Laboratory in Richland, Wash., and the University of Maryland.
Unlike similar studies, the new analysis also provides an estimate of how accurate this study's emissions tally is. Referred to as "uncertainty," the accuracy estimate arises from difficulties inherent in tracking sulfur. This study estimates that actual emissions for recent decades lie within 10 percent of the average global emissions reported by Smith and his colleagues. Regional values could potentially be off by a much higher degree -- up to 30 percent in China, for example.
"The regional uncertainty can be moderately high, but the global numbers are much more accurate," Smith said. "Understanding the uncertainty will help us determine how sensitive the earth's atmosphere and land are to changes in sulfur content."
The Industrial Age ushered in widespread combustion activities that spew sulfur into the atmosphere. Sulfur dioxide has the potential to acidify rain, soil and lakes, and it can counteract some of the warmi
|Contact: Mary Beckman|
DOE/Pacific Northwest National Laboratory