Variability of rainfall in Suriname and the relation with ENSO-SST and TA-SST

摘要

Spatial correlations in the annual rainfall anomalies are analyzed usingprinciple component analyses (PCA). Cross correlation analysis andcomposites are used to measure the influence of sea surface temperaturesanomalies (SSTAs) in the tropical Atlantic and tropical Pacific Ocean withthe seasonal rainfall in Suriname. The spatial and time variability inrainfall is mainly determined by the meridional movement of theInter-tropical Convergence Zone (ITCZ). Rainfall anomalies tend to occurfairly uniformly over the whole country. In December-January (short wetseason), there is a lagged correlation with the SSTAs in the Pacific region(c_lag3Nino1+2=-0.63). The strongest correlation between theMarch-May rainfall (beginning long wet season) and the Pacific SSTAs isfound with a correlation coefficient of c_kNino1+2=0.59 at lag1 month. The June-August rainfall (end part of long wet season) shows thehighest correlation with SSTAs in the TSA region and is about c=-0.52 forlag 0. In the September-November long dry season there is also a laggedcorrelation with the TSA SSTAs of about c_lag3=0.66. The differentcorrelations and predictors can be used for seasonal rainfall predictions.