华北盛夏台风低压暴雨的能量分析

THE ENERGETIC ANALYSIS Of THE TYPHOON LOW PRESSURE AND ITS TORRENTIAL RAIN IN SUMMER NORTH CHINA

利用辐散风和旋转风动能平衡方程，分析了1996年8月3日至5日由浙江沿海登陆北上的台风与西风带系统相互作用产生的暴雨过程．计算并分析了暴雨增幅时台风低压扰动区域内平均的动能收支和转换特征，揭示了台风低压维持的机制及其与外围暴雨增幅之间的关系，得到的结论可供制作北上台风及其暴雨预报时参考。

Dure to the influence of the typhoon 9608 and its low pressure, there is torrential rain inNorth China from 3rd to 5th Ang. 1996, the torrential rain depends on the high energy andvapour the typhoon low pressure provibes. Using the halance equation of kinetic energy for the divergent wind and the rotational wind, calculation is made of the arca-averaged energetic budgetsand conversions over the region of the typhoon low pressure during the amplification of the torrential rain in order to indicate the maintaining mechanism of the typhoon low pressure and the relationship between the typhoon low pressure and its outside enhancing torrential rain. The following are the results: (1) The vertical total kinetic energy from surface to 100hPa of the typhoonlow pressure region is growing during the amplification of the torrential rain, it helps maintainthe typhoon low pressure. The growth of the total kinetic energy mainly comes from the rotational wind energy. (2) In the horizontal flux of the vertical total layers of the trosposphere, HF,convergence is shown, it is divergence in the upper trosposheric (300hPa- 100hPa) layer butcovergence in the low layer (800hPa-1000hPa). The kinetic energy generation term G is positive in every larer of the trospospher, showing thatthe pressure field powering (especially in lowlayer) is the source of energy for maintaining the typhoon low pressure. The vertical total of thedissipotion term R is-21.05W/m2, showing that there is the dissipetion of large-scale kinetic energy to maintain the cummulus convection of the typhoon low pressure. The convergence of thehorizontal flux and the generation of the kinetic energy make the typhoon low pressure decreaseless and helps maintain the torrential enhancement.