【作者】 崔茂常； 莫军； 乔方利；

【Author】 Cui Maochang, Mo Jun, Qiao Fangli (Institute of Oceanology, Chinese Academy of Sciences,Qingdao 266071 China; Key Laboratory of Marine Science and Numerical modeling of SOA, Qingdao 266061 China)

【机构】 中国科学院海洋研究所； 国家海洋局海洋环境科学和数值模拟重点实验室；

【摘要】 采用典型相关分析方法研究了热带太平洋、印度洋海面水温与相关大气环流的变异规律,结果表明:在季节时间尺度下,中部型El Nino事件发生时热带印度洋海温变化呈现相反的趋势,东部海温降低、西北、中南部海温升高;东部型El Nino事件发生时热带印度洋海温普遍升高,尤以马达加斯加岛北偏东海域为甚;在年际时间尺度下,亚洲大陆高压增强、阿留申低压加深南移,触发El Nino事件,热带印度洋海温东降西升。反之触发La Nino事件,热带印度洋海温东升西降;在年代际时间尺度下,热带太平洋、印度洋海气系统的变异含有两个基本模态。其一是亚洲大陆高压增强、阿留申低压加深南移使得热带中、东太平洋海温大面积升高并向副热带太平洋扩展,热带印度洋海温以马达加斯加岛周边及东北海域为中心普遍升高。然后海气变异逐渐逆转。其二是亚洲大陆高压增强、阿留申低压滞留原地甚至消失, 热带中太平洋和温带北太平洋海温略降,其它海域水温微升。热带印度洋海温南升北降,升温尤以马达加斯加岛东南海域为甚。反之亦然。除冬季亚洲大陆高压增强和阿留申低压加深南移可能触发El Nino事件外,全球变暖的线性递增趋势对于El Nino事件的发生也有一定影响。更多还原

【Abstract】 Canonical correlation analysis (CCA) is adopted in the present paper to stud-y the SST variability in the tropical Pacific, Indian Ocean and related air circulation and the results show that: on the seasonal time scale, the SST variations appear contrarily in the tropical Pacific and Indian Ocean. During El Nino years, the anomalous SST decreases in the east but increases in the northwest and south-middle of the tropical Indian Ocean, specially in east of Madagascar Island. And vice versa during La Nina years. On the yearly time scale, when Asian continent high increases and Aleutian low decreases shifting southeastward, both of them trigger the El Nino events. Contrarily, the La Nina events take place. On decadal time scale, there are two basic modes of air-sea system over the tropical Pacific and Indian Ocean. Firstly, when the Asian continent high increases and Aleutian low decreases shifting southeastward, the anomalous SST increases in the middle and east of the tropical Pacific, extending to the subtropical regions, and so in most of the tropical Indian Ocean, specially in northeast of Madagascar Island and nearby. And vice versa.Secondly, when the Asian continent high increases and Aleutian low remains fixed or even disappears, the anomalous SST decreases slightly in middle of the tropical Pacific and the temperate northern Pacific but increases weakly in other regions:the anomalous SST increases in the south but decreases in the north of the tropical Indian Ocean, the SST increases more obviously in southeast of Madagascar Island. And vice versa. The linear trends of global warming seems to play a certain role for El Nino onset except the Asian continent high increasing and Aleutian low decreasing and shifting southeastward.更多还原