Abstract
The impact of SST anomalies on the dynamical long-range forecast of monthly mean fields in the early summer of 1983, which was studied by Tokioka et al. (1987; TYC 87), is examined again. The shortcomings in the results of TYC 87 are eliminated by including SST anomalies over the Indian Ocean, using a modified Arakawa-Schubert cumulus parameterization and using the 15 layer model.
In the tropics, anomaly correlation coefficients are high both in the first and the second month in the present study, while they are low in the second month in TYC 87. The model simulates the intraseasonal variation in the tropics. The forecast skill in mid-latitudes for the second month is higher than that of TYC 87 both in the Northern and Southern Hemispheres.
The results of the present study are encouraging for the dynamical long-range forecast of monthly mean fields beyond one month with the use of real SST and a good model.
