川渝冬季降水的年际变化及其与海温异常的关系

为了认识川渝冬季降水与海温之间的关系，利用川渝地区44个站点降水资料和海表温度资料并借助EOF分解、小波分析和相关分析等方法，讨论了川渝冬季年际降水变化特征及其与前期海温异常之间的关系。结果表明：川渝冬季年际降水空间分布主要有3个类型，EOFl型为川渝冬季降水的一致偏多（偏少），EOF2型为川渝西南部、东部降水偏少（偏多），而川渝地区西北部、中部降水偏多（偏少）；EOF3型为川渝西南部降水偏多（偏少），而东北部降水偏少（偏多）；EOF1型和EOF2型降水与前期海温的相关明显小于EOF3型并较为分散，EOF3型降水与前期夏季、秋季海温在热带中、东太平洋和印度洋中、北部呈现非常显著的正相关，对应ENSO特征非常明显。

Interannual Variations of Winter Precipitation in Chongqing and Sichuan regions and Their Relationship with the Sea Surface Temperature

In order to understand the relationship between winter precipitation in Chongqing and Sichuan regions and Sea Surface Temperature, by using the precipitation observations from 44 stations in Chongqing and Sichuan regions, Sea Surface Temperature and some methods, such as EOF, Wavelet Analysis and Correlation analysis, the inter-an- nual variations of winter precipitation in Chongqing and Sichuan regions and their relationship with Sea Surface Tem- perature has been discussed. The results are presented below： the principal modes of winter precipitation in Chongqing and Sichuan regions are in the first three EOFs patterns. The EOF1 pattern shows winter precipitation above normal （below normal） in all Chongqing and Sichuan regions. The EOF2 pattern shows precipitation below （above） normal in southwest and eastern of Chongqing and Sichuan regions, but above （below） normal in northwest and middle area. The EOF3 pattern shows precipitation above （blow） normal in southwest and below （above） normal in northeast regions. The significant correlation between precipitation and SST in EOF3 pattern is higher than that in EOF1 pattern or EOF2 pattern. It shows significant positive correlation between the EOF3 pattern precipitation and the pre-summer and autumn SST in the tropical central and eastern Pacific and the central and north Indian, the EN- SO characteristics are very obvious.