南海灾害性土台风统计分析

THE STATISTICAL ANALYSE TO THE LOCAL HARMFUL TYPHOON OF SOUTH CHINA SEA

根据台风年鉴资料统计分析了南海热带气旋(指在南海海域生成的热带气旋、又称南海灾害性土台风、下面简称TC),TC数量逐年逐月变化较大,除3月没有TC出现外,其余月份均有TC出现,年生成最多的TC为11个,最少的为1个,年平均6.2个,月生成最多的TC为5个,最少的为零个。TC登陆最多的是8月,12月至翌年4月没有TC登陆中国大陆,登陆范围主要在汕头至海南岛之间。TC的持久期一般均在4～7天,最长亦有19天。南海上生成的TC只有15%能够加强为台风,均集中在水深超过150米的海域。南海是TC发生频繁、数量较多的海域。

The yearbooks of typhoon are used to statistically analyze tropical cyclones in the South China Sea (Tropical cyclones of South China Sea here mean those formed in South China Sea, to be abbreviated as TC in the following text).TC quantity changes greatly month by month and year by year. Except for March, TC appears in all the other months. There are 11 TCs forming at most and 1 TC at least annually. There are five TCs at most and zero at least in terms of monthly formation. The time TC makes the most landfall is August, and from December to the following April no TC lands in China mainland. Landfalls mainly occur between Shantou and Hainan Island. TC lasts for 4-7 days generally and 19 days for the longest duration. About 15% of the TCs in the South China Sea intensify into typhoons, and all of them concentrate in the sea area where the depth of water is over 150 meters. The South China Sea is the area where TC happens frequently and also has a fairly large number.