热带气旋“浣熊”引发广东南部沿岸大暴雨分析

应用NCEP 1白1?的再分析资料、常规观测资料及地面加密观测资料分析2008年4月热带气旋“浣熊”引发的广东南部沿海地区大暴雨过程成因，结果表明：此次大暴雨过程是在南亚高压加强并向西北方向移动控制华南沿岸及南海北部，同时“副高”减弱东退的大尺度形势背景下发生的；南亚高压和“副高”之间存在“反向”而行的短期互动，而这种互动对大暴雨过程有重要影响；热带气旋向偏北方向移动过程中与高原东侧东移南下的槽在广东南部沿岸合并是引发大暴雨的重要天气系统；暴雨区上空存在对流不稳定，大陆冷高压东移出海过程大气边界层内回流弱冷空气是大暴雨过程不稳定能量释放的促发机制；大暴雨过程水汽源地是西太平洋和南海，来自西太平洋和南海的水汽在暴雨区上空辐合为大暴雨过程提供了充足水汽；大暴雨降落在热带气旋路径的右侧而不是热带气旋中心的四周，其原因是水汽和风场的辐合均发生在热带气旋路径的右侧，这是由热带气旋自身环流和大尺度环境气流共同决定的。

Analysis on Heavy Rainfall in Coastal Areas of Guangdong Province Caused by the Landfall Typhoon “Neoguri”

Based on NCEP/NCAR reanalysis data with the resolution of 1°×1° four times a day,conventional observation data,added surface observation data with higher spatial and temporal resolution,the atmospheric large scale circulation,water vapor condition and convective instability condition et al.related to the heavy rain(the daily precipitation amount over 100 mm) process induced by the typhoon "Neoguri" were analyzed in order to explore the cause of the heavy rain process.And the results show: the heavy rain process occurred under the atmospheric large-scale circulation background of South Asia High strengthening and moving from the southeast to the northwest,and West Pacific Subtropical High weakening and retreating from the west to the east.High-level(500 hpa) trough which moved to the southern coast areas of Guangdong from the east side of the Qinghai-Tibet Plateau was incorporated with the typhoon "Neoguri" in southern coastal areas of Guangdong,which are the important synoptic systems that caused the heavy rain.There were convective instability phenomena,wind and moisture convergence over the heavy rain area.The West Pacific Ocean and the South China Sea are the common water vapor source areas of the heavy rain process.The interactions of the typhoon "Neoguri" circulation itself and the southwest circulation of West Pacific subtropical High lead to that convergence of the wind and water vapor occurred in the right side areas of the typhoon "Neoguri" route,and which finally casused the heavy rain occurred in the right side areas of the typhoon "Neoguri" route.