热带西南印度洋上升流区季节和年际变化研究及与印太系统海气相互作用  

The study of upwelling seasonal and interannual variability and its interaction between air and sea in the southwest tropical Indian Ocean

作　　者：蔡怡[1] 凌铁军[1] 张志华[1] 陈幸荣[1] 

机构地区：[1]国家海洋环境预报中心,北京100081

出　　处：《海洋学报》2012年第6期42-49,共8页

基　　金："973"项目"南大洋-印度洋海气过程对东亚及全球气候变化的影响";自然科学基金"用海洋非-boussinesq近似耦合模式研究全球变暖对海平面及相关物理量的影响"资助

摘　　要：用59年Ishii再分析温度资料,讨论了热带西南印度洋(SWTIO)上升流区的季节和年际变化以及与上升流区有关的温度距平的变化,同时分析了其与热带印太海气系统的关系,结果显示SWTIO上升流在南半球冬、夏季比较强,春季最弱。它的范围在5°～1°S,在东西向从50°E可以伸展到90°E。该上升流区的变化与温跃层的温度距平有密切的关系,并存在明显的5a振荡周期。SWTIO上升流区温度距平的5a周期振荡是由热带东印度洋温度距平在最大垂直温度距平曲面(MTAL)上向西沿着11.5°～6.5°S传播过来的,它与热带太平洋的温度距平传播方式不同。SWTIO上升流是热带印太海气系统的一个重要组成部分,印度洋偶极子超前SWTIO上升流区温度变化5个月,最大相关系数达到0.57,NINO3区指数超前SWTIO上升流区指数2个月达到0.49。当热带印太区域的大气风场改变,影响热带太平洋和印度洋表层SSTA,出现ENSO和DI-POLE,进一步向西传播到SWTIO次表层,导致SWTIO上升流区出现改变。Based on the ocean temperature reanalysis data of Ishii etc,this paper discusses the seasonal and interannual variability of upwelling region in southwestern tropical India Ocean（SWTIO） ,the temperature anomalies related to the upwelling region, and the relationship between the variations and tropical India and Pacific Ocean air-sea system. The study shows that the upwelling in SWTIO is the strongest in summer and winter and weakest in spring in the southern hemisphere. The scope extends 5°- 10°S from north to south and 50°-90°E from west to east. The variations of the upwelling region are closely related to the temperature anomalies on the thermocline and there is an outstanding 5 a oscillation cycle. The oscillation propagates along the path of 11.5°- 6.5os to the west on the vertical maximum temperature anomaly level （MTAL） from eastern tropical India Ocean. The propagation is different from the temperature anomalies propagation in tropical Pacific Ocean. The SWTIO upwelling is an important component of the air-sea in- teraction system of India-Pacific Ocean. The India Ocean DIPOLE index is 5 months ahead of the tempera- ture changes of the SWTIO upwelling region and the maximum correlation coefficient reaches 0.57. The NINO3 SST index is 2 months ahead of the temperature changes of the SWTIO upwelling region and the correlation coefficient reaches 0.49. The changes of wind field above tropical Indian-Pacific Ocean impact the changes of SSTA on the surface of tropical Pacific and India Ocean,leading to the cycle of ENSO and DIPOLE and further triggering the changes in the upwelling region of SWTIO.

关 键 词：热带西南印度洋上升流 印度洋偶极子 太平洋ENSO 印太海气系统 

分 类 号：P724[天文地球—海洋科学] P732.6