STRESS ON THE MEDITERRANEAN OUTFLOW PLUME .2. TURBULENT DISSIPATION AND SHEAR MEASUREMENTS

Bottom and interfacial stresses on the Mediterranean outflow plume are estimated using vertical profiles of turbulent dissipation and veloci ty collected in the Gulf of Cadiz. Turbulent dissipation is high throu ghout the plume, with a local minimum often present near the plume nos e (depth of maximum downstream velocity). Bottom stresses are estimate d by applying a log-layer model to the dissipation measurements. The d issipation measurements are also divided by plume-scale vertical shear from the horizontal velocity profiles to construct profiles of stress within the plume. The mean stress estimates in the bottom layer agree well with those calculated in the log layer from the dissipation meas urements alone. The bottom-layer means are slightly larger than those of the interfacial layer. The maximum stresses in each layer are uncer tain, since they depend on the ill-defined shape of the stress profile s within the plume. Dissipation-derived stress estimates in the log la yer and those from dissipation measurements combined with the plume-sc ale vertical shear of horizontal velocity are roughly one-third the ma gnitude of those made in the log layer from velocity measurements and those made in the interfacial layer from the residuals of bulk mass an d volume budgets (Part I). Possible reasons for this discrepancy are a dvanced.