Abstract
The Center for Ocean-Land-Atmosphere Studies (COLA) has recently developed an anomaly coupled prediction system, using sophisticated dynamical ocean and atmosphere models, that produces skillful forecasts of the tropical Pacific sea surface temperature anomaly (SSTA) up to 1.5 years in advance. The details of this coupled prediction system are described by Kirtman et al. and a brief description of the overall skill of the 30 hindcast predictions was given in the March 1995 issue of this Bulletin. We have separately tested the ocean and atmosphere component models in order to evaluate their performance when forced by observed boundary conditions and improvements have been made that are also incorporated into the coupled prediction system. In order to better sample the annual cycle we have doubled the hindcast ensemble from the original 30 cases to 60 cases. Considering all 60 cases, the Nino 3 correlation remains above 0.6 for lead times of up to 12 months.