Wintertime northern hemisphere response in the stratosphere to the Pacific Decadal Oscillation using the Whole Atmosphere Community Climate Model

A 200-yr preindustrial control simulation that includes fully interactive chemistry, ocean and sea ice, constant solar forcing, and greenhouse gases fixed to 1850 levels is analyzed. Based on principal component analysis, the PDO spatial pattern, frequency, and amplitude agree well with the observed PDO over the period 1900-2014.

Consistent with previous studies, the positive phase of the PDO is marked by a strengthened Aleutian low and a wave train of geopotential height anomalies reminiscent of the Pacific-North American pattern in the troposphere. In addition to a tropospheric signal, a zonal-mean warming of about 2 K in the northern polar stratosphere and a zonal-mean zonal wind decrease of about 4 m s-1 in the PDO positive phase are found.