Wintertime Northern Hemisphere response to the Pacific Decadal Oscillation in WACCM

The Pacific Decadal Oscillation (PDO) is defined as the leading mode of sea surface temperature variability in the North Pacific (20˚-60˚N, 110˚E-100˚W) when carrying out a principle component analysis. In both observations and in WACCM, the PDO shows marked variability at decadal to multi-decadal timescales. The positive PDO phase is characterized by warm sea surface temperature (SST) anomalies over the northeastern Pacific and west coast of the United States with alternate cold anomalies over the central North Pacific. The phase of the PDO has been shown to influence tropospheric precipitation, temperature, sea-level pressure, and height patterns. Here, we show the PDO in WACCM and its influence on the wintertime northern hemisphere troposphere and stratosphere. Results suggest a weaker polar vortex in the positive PDO phase, which may have implications for decadal prediction.