Result Analysis of Intensive Sounding Data Assimilation in GRAPES System

By using of the numerical model GRAPES and its 3D-VAR system,some contrast tests on the assimilation of intensive conventional sounding data have been researched based on two strong rainstorm occurred in Sichuan Province in 2011.The results show that both the average and maximum adjustment of all model variables increase with height.The analysis on the horizontal distribution of the innovation field of the two cases indicates that the influential area is limited to Sichuan Province in test B while the influential area in test C is the region of numerical integration.The distribution of innovation field in test D is similar to that in test C but with greater adjustment.In addition,compared to the Control test,test B,C and D all improve the precipitation forecast and test D is the best with forecast of both the precipitation region and intensity closer to reality.