通过对2000—2008年更高空间分辨率的南海海面温度(SST)的卫星遥感数据进行经验正交函数(EOF)分析,着重研究21世纪以来整个南海海域SST年际变化的时空变异,并探讨了其与南海海面风场和海面高度的关系,以及期间南海发生的两次负异常事件的特点和成因。SST年际变化的第一模态表现为全海盆同相变化,年际振荡主要发生在深海海盆区,最大的振荡中心出现在吕宋海峡西部和中南半岛东南海区;第二模态呈东西反向的分布特征,异常中心位于吕宋海峡以西区域。结果还表明,南海SST年际变化与经向海面风有密切关系:SST第一模态滞后经向海面风第一模态3个月,最大相关系数为0.74;而SST第二模态和经向海面风第二模态同步时相关系数达到最大,为0.71;SST的第二模态和南海海面高度异常年际变化以及热带太平洋Nio3.4指数和南方涛动指数也有较好的相关,具有大尺度的特征。
Using 9 years(2000—2008) of the high resolution satellite data,the studiy shows the interannual variability of sea surface temperature in the South China Sea,and its relations with the sea surface wind and sea surface height and the characteristics of two cold anomaly events during the study period are discussed.The first EOF mode of the interannual variability of the SST represented the basin scale in-phase change and the interannual oscillation mainly occurred in the deep basin with the oscillation center in the area west of the Luzon Strait and southeast of the Indochina.The results also show that the interannual variability of the SST in the South China Sea is closely associated with the meridional sea level wind: the first mode of SST is obviously correlated with the first mode of sea level wind at 3 month lag,with a correlation coefficient of 0.74;while the second EOF mode of the SST and meridional sea lavel wind is also highly correlated with each other with a correlation coefficient of 0.71.In addition,the second SST EOF mode is clearly correlated with the sea surface height anomaly and also the Nio3.4 index and Southern Oscillation index,showing large scale characteristics.