海南岛一次特大暴雨过程的成因分析

Analysis of a Rainstorm Process Happened in Hainan Island

利用NCEP 0.5°×0.5°全球再分析资料和中尺度自动站雨量观测,雷达资料等,综合分析2010年10月海南岛秋季一次特大暴雨过程,并对相关物理量场进行诊断分析。结果表明:此次暴雨是高空低槽、低层东风急流和低压环流共同影响所造成的,持久的东风急流为暴雨区提供了充沛的水汽和能量,水汽通量散度等物理量所揭示出的强水汽辐合中心与强降水中心具有很好的对应关系,辐合越强,暴雨的量级越大。回波的"列车效应"使降水增幅,持续时间长。

Based on 0.5 0.5 Ncep reanalysis data Of 2010, conventional meteorological data, auto station data and Doppler radar echo, the influences of circulation background on Autumn rainstorm in Hainan Island in 2010 are synthetically analyzed, and the physical characteristics are also diagnosed. The result shows that： 1） The rainstorm is resulted by High-altitude low slot, low easterly jet, and low pressure circulation. Lasting low easterly jet provide abundant moisture and energy, the physical quantities as divergence of moisture show the better correspondence between the heavy rainfall center and moisture convergence center. The stronger the convergence the greater the rainstorm magnitude. Doppler ＂train effect＂ increase precipitation, maintain a prolonged precipitation.