Numerical Simulation on the Rainout-Removal of Sulfur Dioxide and Acidification of Precipitation from Stratiform Clouds

The rainout-removal of SO2 and the acidification of precipitation from stratiform clouds are simulated using a one-dimensional, time-dependent model, parameterized microphysically in which dissolution and dissociation of gaseous SO2 and H2O2, and oxidation reaction in aqueous phase are taken into account. The effects of dynamic fac-tors, including updraft flow and turbulent transport, and the concentration of gaseous SO2 and H2O2 being transported into the clouds on pH value of the precipitation, the conversion rate S(IV)－S (VI) and the wet deposition rate of SO2 are discussed.