2

Variability in seasonal forecast skill of Northern Hemisphere winters over the twentieth century

Seasonal hindcast experiments, using prescribed sea surface temperatures (SSTs), are analyzed for Northern Hemisphere winters from 1900 to 2010. Ensemble mean Pacific/North American index (PNA) skill varies dramatically, dropping toward zero during …

Atmospheric seasonal forecasts of the twentieth century: multi-decadal variability in predictive skill of the winter North Atlantic Oscillation (NAO) and their potential value for extreme event attribution

Based on skill estimates from hindcasts made over the last couple of decades, recent studies have suggested that considerable success has been achieved in forecasting winter climate anomalies over the Euro-Atlantic area using current-generation …

The Gulf Stream influence on wintertime North Atlantic jet variability

In this article we investigate the influence of the Gulf Stream sea-surface temperature (SST) front on the North Atlantic eddy-driven jet and its variability, by analysing the NCEP-CFSR dataset and a pair of AGCM simulations forced with realistic and …

The signature of low-frequency oceanic forcing in the Atlantic Multidecadal Oscillation

The Atlantic Multidecadal Oscillation (AMO) significantly influences the climate of the surrounding continents and has previously been attributed to variations in the Atlantic Meridional Overturning Circulation. Recently, however, similar …

The influence of the Gulf Stream on wintertime European blocking

Wintertime blocking is responsible for extended periods of anomalously cold and dry weather over Europe. In this study, the influence of the Gulf Stream sea surface temperature (SST) front on wintertime European blocking is investigated using a …

The response of the Pacific storm track and atmospheric circulation to Kuroshio Extension variability

An index of the Kuroshio Extension front strength is produced using a maximum covariance analysis between sea-surface temperature (SST) and sea-surface height (SSH) gradient observations, and composites of the atmospheric state are presented during …

The emergence of zonal ocean jets under large-scale stochastic wind forcing

The response of a two-layer quasigeostrophic ocean model to basin scale stochastic wind forcing is investigated. As found in many previous studies, long Rossby waves are excited at the eastern boundary of the square model basin and the waves are …