On the left side of the eye, the oceanic mixed layer cooled nearly 3 degrees C and deepened to at least 65m in response to Dennis. Both turbulent entrainment and downwelling contributed to the increased mixed layer depth. Vertical speeds within this layer were 6.5 cm/s (rms) at the peak of the storm with peak speeds of 20 cm/s. Kinetic energy dissipation rates within the mixed layer were approximately 1e-5 W/kg and both these and the vertical velocity appear to scale with the wind stress. The float trajectories were dominated by large eddies which repeatedly crossed the entire mixed layer in a regular pattern, cooling at the surface and then carrying this heat into the bulk of the layer. The surface cooling, roughly 1000 W/m^2, accounted for only a small part of the net cooling of the mixed layer, roughly 5000 W/m^2. Most of the cooling was due to cold water entrained from below.
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