An Estimation of Dry Deposition of Sulfur Compounds in Japan

Abstract

Dry deposition velocities for sulfur dioxide and particulate sulfate over the terrestrial and nearby oceanic regions in Japan are computed. Surface roughness scale lengths and residences for sulfur uptake are estimated from consideration of land use characteristics and the biological status of vegetation for warm season conditions. Average deposition velocities and deposition rates for sulfur for 80 km mesh grid cells are presented. Estimated deposition velocities are 0.41 cm/s for sulfur dioxide and 0.21 cm/s for sulfate. Total sulfur deposition in Japan is about 0.30 TgS/0.5 y, this value is almost equal to the wet deposition of sulfate for this season. Dry deposition of sulfate is relatively small, sulfur dioxide is found to contribute most of the total dry deposition of sulfur compounds in our country.
This method has the virtue of being able to predict long term deposition patterns using the climatological and environmental data for use in studies of regional air pollution in East Asia.