鲁中山区地形对山东省一次暴雨影响的敏感性数值模拟试验

NUMERICAL SENSITIVITY SIMULATION OF THE TOPOGRAPHIC EFFECTS ON HEAVY PRECIPITATION IN SHANGDONG PROVINCE

利用PSU/NCAR MM5V3中尺度数值模式进行了鲁中山区地形对一次台风暴雨的数值模拟敏感性试验,结果分析表明:鲁中山区地形作用对山东省暴雨有重要影响,迎风坡可引起低层气流和水汽的辐合上升运动增强,降水量增加,但偏北气流在迎风坡的水汽辐合不明显,降水量影响不大;山顶引起低层辐合上升运动减弱,辐散下沉运动增强,降水量减小;背风坡引起低层气流和水汽的辐合上升运动增强,降水量增加。

The heavy precipitation event is simulated by the PSU/NCAR mesoscale model （MM5） in the mountain area of Shandong province. It is found that the topography of Shandong province has significant effects on the intensity of the heavy rain area. On the windward side, the divergence and moisture divergence at low level is reduced by the terrain lifting effect, and the precipitation was increased. And the divergence at the top of the mountain is increased, which leads to increase the downward vertical velocity, and reduce the precipitation. At the same time, on the leeward side, the precipitation is decreased by the reduction of the divergence.