海气系统异常与广东夏季旱涝的关系

利用广东境内分布较均匀的15个测站的降水资料,分析了热带东太平洋地区的海温和南海海温的变化对广东夏季(5～8月,下同)降水的影响,旱(涝)年的前期和同期的大气环流差异,以及广东夏季降水的周期性。结果表明,在ENSO年广东偏涝,而在ENSO次年则偏旱;热带东太平洋年平均△SST与广东夏季降水存在显著的反相关关系;旱年的前期(当年的2～3月)南海海温较涝年偏低;亚洲主要大气环流系统的位置和强度的变化趋势在旱年和涝年的前冬以及同期几乎是相反的;广东夏季降水存在准2～3年、6～7年、34年和11年振荡周期。

The Relationship between the Anomalies of Sea--Air System and the Drough/Flood in Guangdong during Summer Season

Using the rainfall data observed in 15 stations in Guangdong Province, this paper analyzed the variation of the sea surface temperature (SST) over the tr- opical eastern pacific and the South China Sea and its effects on the rainfall in Guangdong during summer and found that there are obvious differences in the general circulation during drough summer and flood summer and their prev- ious winters. The variation periodicity of the rainfall was also analyzed. The results show that (1) there is more rainfall in Guangdong during the summer of ENSO year, but less in the next year, (2) the variation of rainfall of Guangd- ong is out-of-phase with that of the annual anomaly of SST over the tropical eastern pacific, (3) the SST for February and March over the South China Sea is lower in the drough summer year than in the flood summer year, and (4) the major oscillation periods of rainfall in Guangdong are 2-to 3-year, 6-to 7- year, 34-year and 11-year.