A general circulation model (GCM) sensitivity study was carried out to investigate the influence of global sea surface temperature (SST) on Sahel rainfall. This study was inspired by the model simulations of Sahel rainfall reported by scientists at the Hadley Center. The model was integrated from June through September with three different atmospheric initial conditions and four years (1950, 1958, 1983, and 1984) of SST. The simulated rainfall anomaly patterns bear little resemblance to the observed rainfall anomaly patterns; however, in three out of four cases (1950, 1983, 1984), the area-averaged simulated rainfall anomaly was consistent with the observations. The southward shift of the ITCZ in 1983 and 1984 was simulated as observed. However, the model's internal variability was rather large. This model failed to simulate the rainfall anomaly for 1958. Additional model experiments are needed to establish the role of SST variation in determining the Sahel rainfall variation.
Complete copies of this report are available from:
Center for Ocean-Land-Atmosphere Studies
last update: 21 May 1997
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