Teleconnections between El Nio/Southern Oscillation (ENSO)

North Atlantic Oscillation (NAO)

Indian Ocean Dipole (IOD) and Pacific Decadal Oscillation (PDO) and seasonal and annual precipitation regimes over the Pearl River basin have been analyzed based on the Rotated Empirical Orthogonal Functions decomposing the seasonal and annual precipitation into temporal and the associated spatial patterns. Furthermore

changes in the seasonal and annual occurrence and intensity of wet days linked to the ENSO

NAO

IOD and PDO indices have also been investigated to discover the influences of the climate indices on precipitation regimes. The results show that: ① ENSO and NAO are the leading driving factors for seasonal and annual precipitation variability over the Pearl River basin. The spring precipitation is positively related with NAO and PDO

and is negatively related with ENSO and IOD. The summer precipitation is negatively related with NAO. The autumn precipitation is positively related with ENSO and IOD. The winter precipitation is positively related with ENSO and NAO. And the annual precipitation is positively related with NAO and IOD. ② ENSO

NAO

IOD and PDO affect seasonal and annual precipitation mainly by changing the occurrence and intensity of wet days in the Pearl River basin

and this effect has seasonal differences.