近50年华南沿海SST热事件变化的时空特征

Spatial and temporal variations of high sea-surface temperature events during 1960?2009 in the coastal waters off South China

根据华南沿海10个海洋站1960—2009年实测海表温度(SST)资料统计分析了近50年华南沿海SST热事件时空变化特点,得出如下结论:华南沿海SST热事件主要出现在6—8月份,SST热事件出现的频率以北部湾东北部海域最高,粤东沿海最低;导致SST热事件海区差异的原因是上升流及热带气旋存在海区差异;受全球气候变暖的影响,华南沿海年均SST有上升趋势,近50年来气候变化可划分为冷、暖两个时期,其相对暖期SST热事件的年频数、累计天数、每次SST热事件持续天数较相对冷期均有增加趋势。

Based on the observed sea-surface temperature（SST） data from 10 ocean observation stations in the coastal region off South China（CRSC） from 1960 to 2009,the authors analyzed the variation characteristics of the high-SST events over the 50 year record.The results show that the high-SST events mostly happened during June to August,and most often in the northeast of the Beibu Gulf and least in the coastal waters off eastern Guangdong Province;the regional difference of high-SST events was caused by regional differences of upwelling and tropic cyclone,with yearly-averaged SST showing a rising trend under global warming.The past 50 years can be divided into two periods of relatively warm and cold.The yearly frequency and the number of days in all of the high-SST events in the relatively warm period and the lasting time of every high-SST event both showed rising trends compared with the relatively cold period.