UPPER-OCEAN INERTIAL CURRENTS FORCED BY A STRONG STORM .3. INTERACTION OF INERTIAL CURRENTS AND MESOSCALE EDDIES

The interaction of strong near-inertial frequency currents generated b y a storm with preexisting subinertial frequency currents is investiga ted. For 10 days after the storm, the near-inertial currents remain in the mixed layer and the subinertial currents are steady, so their int eraction is particularly simple. Linearized models predict that the fr equency of the near-inertial currents should be shifted by 1/2 zeta, w here zeta is the subinertial vorticity. This theory, combined with val ues of zeta estimated either from velocity measurements or from the vo rticity equation, produces frequency shifts in the inertial currents a t least five times larger than the confidence limits on the observatio ns. Possible explanations include the concentration of zeta in narrow frontal zones and nonlinear wave-wave interactions.