华南近海台风突然增强的初秋季节锁相  

Seasonal lock of rapidly intensifying typhoons over the South China offshore in early fall

作　　者：陆波[1] 钱维宏[1] 

机构地区：[1]北京大学大气海洋科学系,北京100871

出　　处：《地球物理学报》2012年第5期1523-1531,共9页Chinese Journal of Geophysics

基　　金：国家自然科学基金项目(40975039)资助

摘　　要：使用美国台风联合中心(JTWC)的最佳路径资料对近50年(1961—2010年)海南岛至台湾岛之间的华南近海台风路径和强度做统计分析,得到台风增强的季节锁相时段.经过大气变量的物理分解,海陆分布热力强迫的季节风场揭示出:盛夏时节,东亚副热带季风槽位于沿江江南,华南近海盛行西南季风;中秋时节,东亚副热带季风槽南退到南海中部,对华南近海台风的增强没有影响;在夏末秋初的转换季节,东亚副热带季风槽正好位于华南近海,有些台风进入华南近海季风槽中就有可能增强,形成所谓的季节锁相.The best track data from Joint Typhoon Warning Center （JTWC） was used to analyze the tracks and strengths of typhoons over the South China offshore （SCO） between Hainan and Taiwan islands during 1961 to 2010 and find the seasonal lock of the rapid intensified typhoons. After the physical decomposition of atmospheric variables, seasonal winds forced by land-sea heating variations have revealed that （1） during mid-summer the subtropical monsoon trough is located along the Yangtze Rive and its southern basin, which results in a southwesterly monsoon flow prevailing over the SCO; （2） during fall the subtropical monsoon trough shifts to the middle South China Sea, and it cannot change the intensification of typhoon and （3） in early fall the subtropical monsoon trough is in the SCO, so that some of typhoons would be very likely to intensify rapidly once they enter this region.

关 键 词：近海台风 初秋 季节锁相 南海 突然增强 物理分解 

分 类 号：P457.8[天文地球—大气科学及气象学]