摘要: A Eulerian sulfur deposition model is used to study the distributions of sulfur pollutants in East Asia, in which important physical and chemical processes such as transport, diffusion, dry and wet deposition, vertical transportation in cumulus cloud, gas phase chemistry, aqueous phase chemistry and heterogeneous aerosol chemistry are included. Two cases, the periods of 1987.07.02 GMT00-1987-07-03 GMT00(case 1) and 1989-04-20-GMT00-1989-04-21 GMT00(case 2), are studied and the distributions of SO₂ and SO₄^2- in East Asia are shown. It is revealed that the patterns of distributions of SO₂ and SO₄^2- are different under different meteorological conditions. In the upper layer, the concentrations of SO₂ and SO₄^2- are 0.4-1.0 μg/m³ and 0.2-0.5 μg/m³, 4.0-10.0 μg/m³ and 2.0-6.0 μg/m³ in the middle layer. In the surface layer, the levels of SO₂ range from 4.0 to 30.0 μg/m³ and from 2.0 to 8.0 μg/m³ for SO₄^2-. Distributions of SO_x are controlled by emissions in the surface layer, while in the upper layer it is mainly affected by precipitation. The distributions of SO_x show the interaction of emissions, winds and precipitation in the middle layer.