太行山地形对“96.8”暴雨影响的数值试验研究

Simulation Study of Taihang Mountain Terrain Effects on Heavy Rain in August 1996

利用ＭＭ４模式，设计了４种模式地形方案，讨论了太行山地形对“９６．８”暴雨降水量的贡献；并利用垂直运动和水汽通量等物理量，探讨了太行山地形对本次暴雨过程增幅作用的机制。结果显示，太行山地形对本次暴雨过程的降水中心强度及位置有显著影响，具有６０％增幅作用。太行山地形对垂直运动及水汽辐合也都具有增幅作用。模式地形越真实，预报结果越好，地形越高。

With application of four designed simulation schemes,effects of the Taihang mountain terrain on heavy rain in August 1996 was explored by MM4 model,and the mechanism of the increasing precipitation in terms of some elements such as perpendicular motion,vapor flux etc.was discussed.The results show that the terrain affects obviously the intensity and location of precipitation cell,increases rainfall by 60%,and favors the upward current and vapor convergence.It is proved that the closer active terrain is,the better the model forecast will be and the higher terrain is,the more obvious precipitation enhancement effect will be.