Estimating the role of SST in atmospheric surface wind variability over the tropical Atlantic and Pacific

AbstractThe influence of sea-surface temperature (SST) on interannual surface wind variability in the tropical Atlantic and Pacific is estimated using sensitivity experiments with the SINTEX-F GCM and the ensemble spread in a 9-member control simulation. Two additional estimates are derived for both SINTEX-F and the ERA-Interim reanalysis using regression analysis and singular value decomposition. All methods yield quite consistent estimates of the fraction of surface wind variability that is determined by SST and therefore potentially predictable. In the equatorial Atlantic, analysis suggests that for the period 1982-2014 approximately 2/3 of surface zonal wind variability in boreal spring and early summer is potentially predictable, while 1/3 is due to noise. Of the predictable component, up to about 35% may be driven from outside the tropical Atlantic, suggesting an important role for remote forcing and a diminished one for local feedbacks. In the northern tropical Atlantic, only 30% of boreal winter v...