南印度洋偶极子的变化特征及其与ENSO的关系

利用近三十年逐月的OISST和ERSST资料、NCEP2表面风场等资料和数据分析了南印度洋偶极子的形成原因、结构特征.结果表明：南印度洋偶极子形态的年际SST异常出现在10-12月,有两个明显的冷暖中心,达到极值是在次年的2月份,然后在4-5月份消亡;南印度洋偶极子的形成主要是风场、潜热通量起作用,另外,短波辐射通量也对其有重要的影响;SIOD在北半球春冬季出现,达到盛期是在次年的二月份或三月份,超前ENSO9-10个月,且具有季节锁相特征,在70年代中期的年代际气候突变后,SIOD与ENSO的关系显著增强.

The Change Features of the Southern Indian Ocean Dipole and its Relationship with ENSO

Based on the monthly data of the OISST and ERSST from nearly 30 years, NCEP2 surface wind field data, the formation reasons of the southern Indian Ocean dipole and its structure features were analyzed. The results showed that the annual SST anomaly in the form of the southern Indian Ocean dipole appeared during l0 and 12 months, there are two obvious changes in temperature center, maxima is in the following year in February, and then die in April - May; The formation of the southern Indian Ocean dipole mainly affected by wind field, latent heat flux, in addition, the shortwave radiation flux also had important influence on it; SIOD appeared in the northern hemisphere during spring and winter, reached the height is in the following year in February or march, ENSO9-10 months in advance, and has the characteristics of seasonal phase lock, after the decadal climate mutation of the mid 70s, SIOD relationship with ENSO significantly had been enhanced