2010年10月海南岛一次特大暴雨过程数值模拟和诊断分析  

Numerical simulations and diagnostic analysis of an extraordinary rainstorm event in October 2010 over Hainan Island

作　　者：杨仁勇[1] 赵付竹[1] 陈有龙[1] 

机构地区：[1]海南省气象台,海口570203

出　　处：《暴雨灾害》2014年第3期255-263,共9页Torrential Rain and Disasters

基　　金：国家科技支撑课题(2013BAK05B03);国家自然科学基金项目(41365004);华南区域气象中心项目(GRMC2012M09)

摘　　要：使用WRF模式对2010年10月4—6日发生在海南岛的特大暴雨过程进行数值模拟和边界条件敏感性试验。敏感试验表明,使用0.5°′0.5°分辨率的GFS资料作为边界条件模拟效果最好。模拟结果表明,采用4 km水平格距试验模拟的强降雨中心(1200 mm)位置、量级与实况强中心(1084 mm)基本接近,模拟的48 h雨量在海南岛上呈东多西少的分布特点,与实况基本相符,但模拟的西部降雨较实况偏多。同时利用模拟结果对风场、水汽通量散度、假相当位温、低空急流和散度垂直通量等要素进行了诊断分析,结果表明在热带低压、冷空气和副热带高压的影响下,存在着强低空急流、强水汽辐合中心、大气对流不稳定结构及高低空配合较好的辐散辐合作用,使得本次过程上升运动异常强烈,从而产生特大暴雨。Numerical simulation and boundary condition sensitivity experiments on the extraordinary rainstorm over Hainan Island during October 4—6,2010 are simulated by the Weather and Research Forecast(WRF) model. The sensitivity experiments show that: using the highest resolution Global Forecast System(GFS) data as boundary condition can get the best simulation result. The simulation result from 4 km′4 km experiment shows: not only the center position of the heavy rainfall but also the rainfall value(1 200 mm) of the simulation is similar to the observation data(1 084mm); the distribution of 48 h accumulative rainfall amount is successfully simulated which shows the rainfall in east area is higher than in the west, but the rainfall of simulation in the west is higher than the observation rainfall. Based on the numerical simulation results, the diagnostic analysis of field such as wind, water vapor flux divergence, pseudo-equivalent potential temperature, low level jet, divergence vertical flux are also performed, the results show that: under effect of tropical depression, cold air and subtropical high,all the existing strong low-lever jet, strong vapor convergence center, atmospheric convective unstable structure, divergence and convergence with good cooperation of high and low levels had made the upward movement during this event unusually strong, which eventually led to occurring of extraordinary rainstorm.

关 键 词：热带低压 特大暴雨 数值模拟 敏感性试验 海南岛 

分 类 号：P458.121.1[天文地球—大气科学及气象学]