Predictions of ENSO with a coupled atmosphere-ocean general circulation model

Predictions of ENSO are described by using a coupled atmosphere-ocean gener al circulation model. The initial conditions are created by forcing the cou pled system using SST anomalies in the tropical Pacific at the background o f the coupled model climatology. A series of 24-month hindcasts for the per iod from November 1981 to December 1997 are carried out to validate the per formance of the coupled system. Correlations of SST anomalies in the Nino3 region exceed 0.54 up to 15 months in advance and the rms errors are less t han 0.9 degreesC. The system is more skillful in predicting SST anomalies i n the 1980s and less in the 1990s. The model skills are also seasonal-depen dent, which are lower for the predictions starting from late autumn to wint er and higher for those from spring to autumn in a year-time forecast lengt h. The prediction, beginning from March, persists 8 months long with the co rrelation skill exceeding 0.6, which is important in predictions of summer rainfall in China. The predictions are succesful in many aspects for the 19 97-2000 ENSO events.