Seasonal to decadal prediction of the winter North Atlantic Oscillation: Emerging capability and future prospects

Abstract

European and North American winter weather is dominated by year-to-year variations in the North Atlantic Oscillation (NAO) which controls the direction and speed of the prevailing winds. An ability to forecast the time-averaged NAO months to years ahead would be of great societal benefit, but current operational seasonal forecasts show little skill. However, there are several elements of the climate system that potentially influence the NAO and may therefore provide predictability for the NAO. We review these potential sources of skill, present emerging evidence that the NAO may be usefully predictable (with correlations exceeding 0.6) on seasonal time-scales, and discuss prospects for improving skill and extending predictions to multi-year time-scales.