WRF和MM5模式对辽宁暴雨模拟的对比分析

Comparative Analysis of Heavy Rainfall Simulations with Two Mesoscale Models in Liaoning Province

用近年开发的新一代中尺度预报模式WRF（Weather Research Forecast）和已被广泛应用的MM5模式分别模拟研究了2002年8月3～4日发生在辽宁的一次区域性暴雨过程。模拟结果显示WRF模式能够比较成功地反映出导致暴雨发生的高低空环流背景和暴雨的分布状况；WRF和MM5模拟结果的对比分析表明：由于WRF的动力框架具有一定的优越性使得模式结果得到改善，在前处理和所选物理过程相同的情况下，WRF模式对能够代表本次暴雨过程中中尺度天气系统的高度场、风场、散度场、水汽通量场以及垂直速度场等物理量的模拟效果要好于MM5。高空形势场的影响使WRF模拟的降水落区和强度更接近实况。

By means of the new generation numerical forecast model WRF （Weather Research Forecast） and MM5 used widely, a simulation study is conducted on a heavy rainfall process occurred on 3 to 4 August 2002 in Liaoning Province. The results indicate that WRF can rather successfully reflect the circumfluence background in the upper or lower level which induced the rainfall and the rainfall distribution. The comparative analysis of the simulation results made by means of WRF and MM5 shows that owing to the superiority of the WRF＇s dynamic framwork, WRF has better ability to simulate the mesoscale weather system in this heavy rainfall process than MM5 does under the condition of the same physical processes and same pre-processing; the area and intensity of the simulated precipitation by WRF is closer to the fact.