印度洋—太平洋暖池季节变化及其相应的大气环流形式

Seasonal Variations of the Indo-Pacific Warm Pool and the Corresponding Atmospheric Circulation Forms

首先通过对英国大气科学数据中心海表面温度资料和Levitus随深度变化的海温资料的分析,给出了印度洋—太平洋暖池季节变化的详细描述。另外,利用NCEP/NCAR再分析大气资料中的风场数据,采取将水平风场分量分解为无辐散分量和无旋分量的方法,分析了相应于暖池季节变化的大气环流形式。得到了这样的结论:第一,印度洋—太平洋暖池的位置随季节变化南北移动;暖池面积在北半球的5月和9月达到两个极大值;无论就海表面温度还是深度而言,该暖池分别存在一或两个强度中心。第二,尽管印度洋—太平洋暖池中间被南亚大陆所间隔,但是暖池上空对流层大气运动对于暖池的季节变化却是作为一个整体响应的。

Firstly, the seasonal variations of the Indo-Pacific warm pool are investigated in this paper using the sea surface temperature data set of the BADC and the Levitus subsurface temperature data. Secondly, we studied the corresponding atmospheric circulation forms using the monthly winds from the NCAR/NCEP Re-Analysis Data Set with the method of dividing the horizontal velocity of wind into a non-divergent part plus an irrotational part. It shows that （ 1 ） the location of the Indo-Pacific warm pool shifts with season. The area of the warm pool reaches its maximum in boreal May and September. There are one or two centers for the warm pool. （ 2 ） The atmospheric cell over the warm pool responses to the seasonal variations of Indo-Pacific warm pool as a whole, although the southern Asia land exists between the Indian Ocean and the west Pacific Ocean.