应用GRAPES模式对贵州暴雨过程的模拟试验

Simulation Experiments on Heavy Rainfall Events in Guizhou with GRAPES Model

利用我国新一代数值预报模式GRAPES(Global/Regional Assimilation and Prediction Enhanced System),对2004年发生在贵州的3次强降水过程,即6月23—24日、7月17—18日和7月21—22日的暴雨过程进行了数值模拟,并与实况资料进行对比分析。模拟结果表明:GRAPES模式成功地模拟了这几次降水过程中的主要天气系统的位置和移动过程,如西南低涡的加强、较强的低空急流、低空气流辐合以及高空槽过境等,因此较好地模拟出暴雨的落区和分布特征。但对强降水的模拟与实况有一定差异,对局地暴雨的模拟偏小。模拟试验分析可见: GRAPES模式对贵州暴雨有预报能力,有较好的参考作用。

With the new generation numerical prediction model GRAPES （Global/Regional Assimilation and Prediction Enhanced System）, three typical heavy rainfall events happening respectively in Guizhou Province during June 23--24, July 17--18 and 21--22 of 2004 are numerically simulated, and the result is compared with observation data. The result shows：In all these processes, the movement of the major weather system is simulated by GRAPES model successfully, such as the strengthening of southwest vortex, low level jet, the convergence of low level jet and the passage of upper trough. GRAPES model can successfully simulate the distribution of precipitation. But unfortunately, there are some differences in heavy rainfall between the observations and simulations. The simulation values of the precipitation center less than the observations. From the numerical results, GRAPES model is proved to have good ability to simulate heavy rainfall in Guizhou, and to be of good reference.