All-season regressions of standardized smoothed AMO indices on SSTs for the winter 1900–fall 1999 period. Regressions for the models are calculated for each ensemble member separately and then an average is computed for each model. Red/blue shading denotes positive/negative SST anomalies; contour interval is 0.1 K. The indices are constructed by first calculating a spatial average of SST anomalies over the (5°–75°W, 0°–60°N) region and then detrended, using the least squares method. The indices are finally smoothed by applying a 1-2-1 binomial filter 50 times and normalized by using their standard deviation. Regressions are shown after 5 applications of smth9 in the GRADS plotting software. Bottom Panel Observed HadISST smoothed AMO index and other four model-derived smoothed AMO indices which have the highest correlations, R, with the observed index: GFDL-CM3, Ensemble 5 (R = 0.75), UKMO-HADCM3, Ensemble 4 (R = 0.56), ECHAM6/MPI-ESM-LR, Ensemble 3 (R = 0.01) and CCSM4 Ensemble 4 (R = 0.29). The correlation range for the different ensembles within each model is shown adjacent to the model’s name