Interdecadal modulation of PDO on the impact of ENSO on the east Asian winter monsoon

The interdecadal modulation of the Pacific Decadal Oscillation (PDO) upon the impact of the El Nino-Southern Oscillation (ENSO) on the east Asian winter monsoon (EAWM) is investigated. When the PDO is in its high phase, there is no robust relationship between ENSO and EAWM on the interannual timescale. When the PDO is in its low phase, ENSO exerts strong impact on the EAWM, with robust and significant low-level temperature changes occurring over east Asia. The contrast in ENSO's influence between the two phases of the PDO is quite remarkable, which urges that the phase of the PDO should be taken into account in the ENSO-based prediction of wintertime climate over east Asia. This modulation may be accounted for by the change in the low-latitude Pacific-east Asian teleconnection and in the response of midlatitude geopotential height to ENSO over Northwest Pacific. Citation: Wang, L., W. Chen, and R. Huang (2008), Interdecadal modulation of PDO on te impact of ENSO on the east Asian winter monsoon, Geophys. Res. Lett., 35, L20702, doi: 10.1029/2008GL035287.