Introducing sub-seasonal spatial and temporal resolution to winter climate prediction

Abstract

The dominant Northern Hemisphere winter mode of variability is characterized by a same-signed sea level pressure anomaly at high latitudes with an opposite-signed anomaly stretching across mid-latitudes. The surface temperature pattern associated with this mode is a same-signed temperature anomaly across the major continents and an opposite-signed anomaly across the major oceans. We demonstrate that this temperature pattern is mostly an artifact of multi-year averaging, which results in the super positioning of two distinctive patterns. Separation of the two patterns allows for more accurate seasonal predictions and introduces a spatial and temporal resolution in forecasts previously not possible.