ON THE EXISTENCE OF AN EL NINO-TYPE PHENOMENON IN THE BENGUELA SYSTEM.

Although there have been several warm and cool periods in the Benguela region off southwestern Africa, only two events which approximate to an El Nino-type situation have occurred, viz in 1963 and in 1984. Although long time series in the Benguela are few, historic records indicate that in March 1950 the 27 degree C isotherm in the eastern Atlantic lay 600 km further south than normal, while there is evidence that a major El Nino-like event occurred here between February and August 1934, with sea temperatures 2-3 degree C above the long term average from March to July 1934. Conditions were clearly anomalous in low latitudes in the Atlantic in 1934 and 1963, while there was a major perturbation in the equatorial Atlantic in 1984. This strongly suggests a nonlocal cause of the Benguela anomalies. It is suggested that there is a South Atlantic equivalent of the Pacific El Nino, but that in the Benguela region these events are less pronounced and less frequent. Their causal mechanism may also be different. The effect of these events on the southern Benguela is minimal.