Variability of the Tropical Ocean Surface Temperatures at Decadal–Multidecadal Timescales. Part I: The Atlantic Ocean

Abstract

Abstract Gridded time series from the Global Ocean Surface Temperature Atlas were analyzed with a variety of techniques to identify spatial structures and oscillation periods of the tropical Atlantic sea surface temperature (SST) variations at decadal timescales, and to develop physical interpretations of statistical patterns of decadal SST variations. Each time series was 110 yr (1882–1991) long. The tropical Atlantic SST variations were compared with decadal variations in a 74-yr-long (1912–85) north Nordeste Brazil rainfall time series and a 106-yr-long (1886–1991) tropical Atlantic cyclone activity index time series. The tropical Atlantic SST variations were also compared with decadal variations in the extratropical Atlantic SST. Multiyear to multidecadal variations in the cross-equatorial dipole pattern identified as a dominant empirical pattern of the tropical Atlantic SST variations in earlier and present studies are shown to be variations in the approximately north–south gradient of SST anomalies....