Rainfall variability in Suriname and its relationship with the tropical Pacific ENSO SST anomalies and the Atlantic SST anomalies

Spatial correlations in the annual rainfall anomalies are analyzed using principal component analysis (PCA). Cross correlation analysis and composites are used to measure the influence of sea-surface temperature anomalies (SSTAs) in the tropical Atlantic (TA) and the tropical Pacific Ocean on the seasonal rainfall in Suriname. It is shown that the spatial and time variability in rainfall is mainly determined by the meridional movement of the inter-tropical convergence zone (ITCZ). The rainfall anomalies are fairly uniform over the whole country. The strongest correlation in the December-January rainfall (short wet season) at station Cultuurtuin is found to occur with the SSTAs in the Pacific region and is about c(k)(Nino) (1+2) = 0.59 at lag 1 month. In the March-May rainfall (beginning of the long wet season), there is a lagged correlation with the SSTAs in the Pacific region (C-lag (3) (Nino) (1+2) = 0.59). The June-August rainfall (end of the long wet season) shows the highest correlation with SSTAs in the TSA region and is about c = -0.52 for lag 0. In the September-November long dry season there is also a lagged correlation with the TSA SSTAs of about c(lag) (3) = 0.66. These different correlations and predictors can be used for seasonal rainfall predictions. Copyright (c) 2006 Royal Meteorological Society