For some years there has been concern that an enhanced Greenhouse Effect may affect the behaviour of the El Nino-Southern Oscillation, which may in turn influence Australian climate variations. The change in the Australian climate relationships appears to have two aspects, an increase in maximum temperatures, relative to rainfall and rainfall appearing to be higher, relative to the Southern Oscillation Index ( SOI), than was the case previously. Seasonal climate prediction for Australia is based largely on lagged statistical relationships between the SOI and rainfall. Since the simultaneous relationship between these variables may have changed, it seems likely that the lagged relationships used in prediction may also have changed. Care will be needed in the interpretation of seasonal forecasts developed on earlier data.
