ENSO背景下南海海表温度异常的跷跷板模态  

The Sea Surface Temperature Seesaw Pattern in South China Sea During ENSO

作　　者：刘雪[1] 林霄沛[1] 

机构地区：[1]中国海洋大学海洋环境学院,山东青岛266100

出　　处：《中国海洋大学学报（自然科学版）》2013年第12期1-6,共6页Periodical of Ocean University of China

基　　金：国家自然科学基金重点项目(40930844)资助

摘　　要：基于多种海洋气象数据,对南海海表温度距平在ENSO背景下的年际变化特征进行了分析。发现南海海表温度距平具有明显的东北-西南反向变化的跷跷板模态:在厄尔尼诺年,南海西南部以越南南部沿岸为中心有明显的升温现象,东北部特别是吕宋海峡附近有明显的降温现象,拉尼娜年份相反。分析南海海表面的净热通量收支,发现除北部较浅的沿岸海外,其对海表温度升高起抑制作用。研究显示,南海海表温度异常的跷跷板模态主要与海洋动力结构变化相关。在厄尔尼诺年,南海西南部正的风应力旋度减弱,Ekman抽吸减弱,冷水上涌减少,导致温度升高;而东北部,则可能是由于低温的吕宋贯通流增强导致的温度降低。Based on various ocean and atmosphere products, the interannual variability of the sea surface temperature （SST） in South China Sea （SCS） during E1 Nino-Southern Oscillation （ENSO） is studied. There is a seesaw pattern over the southeast and northwest of SCS, which is especially robust in winter. During E1 Nino, the SST in the southwest （especially near the south of Vietnam） increases while the SST in the northeast （especially near the Luzon Strait and Taiwan Strait） decreases, vice versa during La Nina. Further analysis shows that the formation mechanism of this seesaw pattern is associated with the ocean dynamics, with heat flux acting to damp SST except on the northern boundary of SCS. In the southern SCS, the reduced cyclonic wind stress curl causes the weakened Ekman pumping, which results in local warming, and the warming center, which is located in the cold tongue area near the south of Vietnam, is associated with the decreased western boundary current because of the weakened northeast wind stress. In the northeastern SCS, the cooling is attributed to the increased transport of the Luzon Strait during EI Ni- no.

关 键 词：ENSO 南海 海表温度 跷跷板模态 热通量 季风 海洋动力 

分 类 号：P731.31[天文地球—海洋科学]