Verification and Improvement of the Capability of ENSEMBLES to Predict
the Winter Arctic Oscillation
Abstract
The winter Arctic Oscillation (AO) is important for understanding the
Northern Hemisphere climate variability and predictability. However,
ENSEMBLES models produce inconsistent predictions when applied to the
interannual variability of the 1962–2006 winter AO. In this study, the
interannual increment of the winter AO index (DY_AOI) during 1962–2006
is first improved by a dynamical‐statistical model with two predictors:
the preceding autumn Arctic sea ice and the concurrent winter
ENSEMBLES‐predicted sea surface temperature over the North Pacific.
Next, the improved final AOI is obtained by adding the improved DY_AOI
to the preceding observed AOI. Because the interannual increment
approach can amplify prediction signals and takes advantage from the
previous observed AOI, this method shows promise for significantly
improving the interannual variability prediction capabilities of the
winter AO during 1962–2006 in the ENSEMBLES models. Therefore, this
study offers important insights for AO predictions, even other climate
variables predictions.