Numerical Simulation Of Influence Of Drop Size Distribution Variation On Cloud And Precipitation

Using the 1AP 3-D hailstorm numerical model, we analyze influence of variation on rainfall amount, hail fallout amount, dynamical process of cloud, microphysical process, mechanism of hail suppression with seeding, and seeding outcome. Besides, we use those study outcomes and bring forward some advice about using and improving model.We simulate a hailstorm occurred in Nanjing county and analyze influence of raindrop, ice crystal, graupel size distribution on outcome of model. The results show that it has no effect on cloud development and cloud structure, when form factors of raindrop, ice crystal, graupel size distribution (r, i, g) vary respectively, r variation has a bigger effect on rainfall amount and hail fallout amount, a, variation has a smaller effect on rainfall amount and hail fallout amount. g variation has a smaller effect on rainfall amount, but has a bigger effect on hail fallout. When r, i, g vary with height at the same time, effect on rainfall amount and hail fallout amount are all bigger, especially, hail fallout amount.Another hailstorm occurred in Xunyi county, Shanxi province on July 9. 1999 is also simulated. By contrasting two different hailstorms in Nanjing and Xunyi county, we analyze the effect of i variation on nature cloud and precipitation, then we analyze the effect of i variation on mechanism of hail suppression with seeding and seeding outcome in two seeding experiments with Agl. The main results show that i variation in two hailstorms has different effect on surface rainfall, surface hail fallout, rainfall intensity, hail fallout intensity. In two hailstorm, i variation has no effect on formation mechanism of particles in cloud, but i variation has different effect on microphysical processes in cloud. After seeding, in two hailstorm i variation has no effect on mechanism of hail suppression with seeding, but has different effect on seeding outcome.