Dynamics of Interdecadal Variability in Coupled Ocean–Atmosphere Models

The interdecadal variability as simulated by coupled ocean-atmosphere models is reviewed. Emphasis is given to that class of interdecadal variability that arises from ocean-atmosphere interactions. The interdecadal variability simulated can be classified roughly into four classes: tropical interdecadal variability, interdecadal variability that involves both the Tropics and the extratropics as active regions, midlatitudinal interdecadal variability involving the wind-driven ocean gyres, and midlatitudinal interdecadal variability involving the thermohaline circulation. Several coupled models predict the existence of different interdecadal climate cycles, with periods ranging from approximately 10-50 yr. This implies some inherent predictability at decadal timescales, provided that these interdecadal cycles exist in the real climate system.