Forecast of sulfur deposition in Japan for various energy supply and emission control scenarios

In order to contribute to the analysis and solution of regional scale envir onmental problems in East Asia, we developed a tool for the comprehensive a ssessment of alternative policy options to improve air quality. This tool p rojects the future regional energy supply, calculates the emission levels o f sulfur dioxide and estimates the geographical pattern of sulfur depositio n resulting from emissions. Sulfur deposition in Japan through 2030 was for ecasted for various energy supply and emission control scenarios using the analysis tool. Future sulfur depositions were calculated from the source-re ceptor matrix for 1995 and the growth rate of emission for the source subre gion. In the case of the current legislation scenario, anthropogenic SO2 em issions in East Asia would grow by 34 percent and sulfur deposition in Japa n would increase by approximately 20 percent between 1995 and 2030. This in crease in sulfur deposition over these 35 years is slightly less than the c ontribution from volcanic emission to sulfur deposition in Japan. In the ca se of the hypothetical dirty scenario for China, sulfur deposition in sever al grids which face the Sea of Japan would double by 2030.