A series of 28 one year hindcast experiments, four each year for the years 1986-1992, were carried out with a coupled ocean-atmosphere general circulation model. The ocean component of the prediction model has a nearly global domain. The coupled model does not employ anomaly coupling or empirical statistical corrections. Initial conditions for the ocean were obtained from an ocean data assimilation system that uses measurements of subsurface ocean temperature as well as surface forcing. The problems of climate drift and initial shock were dealt with by using anomaly initial conditions for the ocean. The anomaly initial conditions were generated by adding the anomalies of the assimilated fields from the assimilation climatology to the coupled model climatology. The hindcasts show considerable skill in the equatorial Pacific. The results of the hindcast experiments are compared to results of a comparable set of experiments performed with another coupled prediction system that uses a Pacific basin domain for the ocean, anomaly coupling and empirical statistical corrections, and no subsurface ocean initial data. The two systems are found to have comparable levels of performance.
Complete copies of this report are available from:
Center for Ocean-Land-Atmosphere Studies
last update: 1 July 1996
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