Global and regional anthropogenic sulfur dioxide emissions
We present a new inventory of global sulfur dioxide emissions from anthropogenic activities for the years 1980–2000. Emissions were estimated in 11 world regions using country-level emissions inventories and regional fossil fuel sulfur content information. Estimated global emissions in 1990 are 72 TgS with an estimated uncertainty of ±8% due to random errors with additional systematic errors that suggest that true emissions may be higher than this central value. We estimate that 56% of 1990 world emissions are from coal, 24% from oil, 15% from industrial processes and 3% from biomass burning. When our results are compared with other studies, they are similar at the global-mean level, but show marked differences at the regional level. Globally, emissions have been roughly constant from 1980 to the present. However, a significant shift has occurred in the spatial distribution of emissions. While 60% of global emissions in 1980 were from around the North Atlantic basin, this region contributed less than 40% of the global total by 1995 and will contribute even less in the future. Currently, based on our estimates, the centrally planned Asia (CPA) region, dominated by China, is the largest contributor to global sulfur dioxide emissions. A gridded data set for 1990 emissions is also produced, including a consistent seasonal cycle and a stratification of emissions into low and elevated releases. Implications for climate modeling and detection studies are discussed.