HEAT-TRANSPORT BY MESOSCALE EDDIES IN AN OCEAN CIRCULATION MODEL

The role of mesoscale eddies in the poleward heat transport in the oce an is investigated; in particular, the compensation of poleward eddy h eat transport by an eddy-induced mean meridional circulation is examin ed. A multilayer isopycnic primitive equation model of an idealized we stern North Atlantic is presented to test whether compensation also oc curs within an isopycnic model and when the poleward eddy heat transpo rt becomes comparable to the mean transport. Also, in this model confi guration compensation of the poleward eddy heat transport arises. It i s brought about by a westward eddy heat transport in the midlatitude j et, which results in a pressure drop across the basin and consequently in a modified mean meridional overturning. This compensation is discu ssed;within the framework of wave-mean flow interaction. It is demonst rated that compensation results from eddy-mean flow interaction when t he diabatic forcing is sufficiently weak; rings are recaptured before their SST anomaly is modified significantly; When the time scale of SS T anomalies is smaller than the lifetime of mesoscale rings, it is hyp othesized that the non-heat transport character of eddies breaks down.