Analysis on the Spatial and Temporal Distribution of the PDO and Its Relationship with ENSO

Using the 2°×2° ERSSTv3 b data (1900 ~ 2013) that from the national climate data center, the spatial and temporal distribution of the Pacific Decadal Oscillation (PDO) was analyzed by using EOF analysis, wavelet analysis, MannKendall method and cumulative departure method. The results show that there is 48 years variation period about the PDO Index.During the 48 years period, a “cold-warm”phase appears alternately, with the “cold” (“warm”) knee points were found around 1925 and 1975 (around 1941 and 1995), respectively. The North Pacific SST is symmetrically distributed around 40°N in the south-north direction. The high value areas distribute from the west coast of North America-Mexico peninsula stretching north to Alaska. The small value areas appear in the north of the Hawaiian Islands and the east of the Japan islands. The correlation coefficient between the PDO Index and the Nino3. 4 Index is 0. 43, which revealed a significant positive correlation. In addition, the corresponding average rate between the PDO Index and the Nino3. 4 Index in abnormal years is 51. 42%.