A Study on the predictability of seasonal temperature in South Africa

Abstract

An analysis of the variability and predictability of seasonal temperature over South Africa is conducted. Possible relationships between global scale sea-surface temperature fields and seasonal temperature over South Africa are sought by means of a statistical technique namely singular value decomposition. Associations between sea-surface temperature and seasonal temperature over South Africa are evident and in particular, associations between El Nino I Southern Oscillation related signals from the oceans and seasonal temperature over the eastern half of the country. Also, a long-term warming trend in the ocean temperatures have important influences on the temperature variability over South Africa. In this study canonical correlation analysis is used to construct a forecast scheme for the prediction of seasonal temperature over South Africa at different lead times. Evolutionary patterns in the ocean temperature field are used as predictors. Categorical seasonal temperatures are predicted and evaluated for an independent test period to verify the skill and therefore usefulness of such predictions.