OBSERVATIONS OF THE VERTICAL STRUCTURE OF THE OCEANIC BOUNDARY-LAYER

The vertical structure of the surface layer of the ocean is examined a t inertial and lower frequencies using observations made from the rese arch platform FLIP in the late winter of 1990. The analysis isolates t he shear supported by density gradients at the base of the mixed layer from that found within the layer. Near-inertial frequency shear varia bility is most energetic at the base of the shallow, well-mixed isothe rmal surface layer. At lower frequencies, significant shear is found w ithin the surface layer. The wind-driven transport is in good agreemen t with the Ekman transport and is divided almost equally between the s urface layer and a less well mixed layer just below. The vertical stru cture of the wind-driven flow within the surface mixed layer varies wi th frequency; it is slab-like near the inertial frequency but strongly sheared at the lowest frequencies.