Summary: | Interannual-to-interdecadal ocean-atmosphere interaction in midlatitudes is studied using an idealized coupled model consisting of eddy-resolving two-layer quasigeostrophic oceanic and atmospheric components with a simple diagnostic oceanic mixed layer. The model solutions exhibit structure and variability resembling many aspects of the climate over the North Atlantic. The atmospheric climatology is characterized by a zonally-modulated climatological jet. The single basin oceanic climatology consists of a midlatitude double jet, representing the Gulf Stream and Labrador currents, which are parts of the subtropical and subpolar gyres respectively. The leading mode of the atmospheric low-frequency variability consists predominantly of meridional displacements of the zonal jet, with a local maximum over the ocean. This mode is found not to be affected by oceanic coupling. Its variability is shown to determine the structure of the sea surface temperature variability both regionally near t.
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