Tropical Climate Prediction: A Progress Report, 1985–90

Abstract

Climate-prediction research in the 1980s has shown particular promise for methods based on (a) general circulation and statistics, and (b) numerical modeling. Empirically based methods of predicting seasonal rainfall anomalies have been presented for India, Java, Kenya, Sahel, and Northeast Brazil. For some of these regions, about half of the interannual rainfall variability can be predicted from antecedent departures in the large-scale circulation. River discharge in northern South America, as well as atlantic tropical storm activity have proven highly predictable on empirical grounds. Numerical modeling has been used to advantage for the prediction of El Niño. Numerical modeling efforts are underway, directed to the forecasting of Sahel rainfall anomalies. Remarkable progress has been made towards the empirical prediction of food- grain production. A sound diagnostic understanding is crucial for the development of both empirical and numerical prediction methods. Among the most important tasks pending are the maintenance and timely processing of reliable, continuously functioning conventional raingauge networks; documentation of methods and verification of forecasts; and enhancement of contacts with the prospective users of climate prediction.