Total global emissions rose dramatically from 1850 to the 1960s, plateaued and then decreased after 1990, and then started rising again in 2000. Although the contribution from major emitters of the past -- North America and Europe -- has been declining since the 1970s, sulfur emissions are rising in much of the rest of the world. Especially noteworthy is China with its phenomenal growth. By 2005, China's share of sulfur emissions came in at 28 percent of the global total, up from about 2 percent in 1950.
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 in importance. They now constitute 10 percent of the global total. Although rising during the study's time frame, a recent international agreement referred to as MARPOL promises to dramatically reduce these emissions in future years.
"Emissions from international shipping have not gone unnoticed," said Smith.
Up and Coming
Although there is no central repository or process to keep this kind of information up-to-date, Smith reports that this data is being used by other researchers from climate modelers to social scientists. An earlier version of the data has already been used in models that are exploring possible futures of global climate, results that will be used in the next assessment by the Intergovernmental Panel on Climate Change (IPCC).
In addition, Smith is curious to see recent emissions data from China, the largest sulfur emitter in the world. "The most recent numbers in this study are from 2005, six years ago," said Smith. "Since this da
|Contact: Mary Beckman|
DOE/Pacific Northwest National Laboratory