Decadal climate predictions with the ECMWF coupled system

In this study we present results of decadal climate hindcasts over the period 1960-2000 carried out with the ECMWF coupled system IFS/Nemo in which both atmosphere and ocean are initialised to bring the state of the coupled model close to the observed state. The ocean conditions have been produced with NEMOVAR, a multivariate 3D-Var data assimilation method. The atmosphere and land surface initialization was from the ERA-40 and ERA-Interim reanalysis. The skill of the model in reproducing the observed coupled teleconnection patterns and the leading modes of interannual variability in the atmosphere is evaluated. An assessment of the extent to which near-surface air temperature is are skilfully predicted in the forecast range from one to ten years is shown as well.