The Benthic Boundary Layer is a region close the ocean bottom with features distinct from the oceanic interior. Near the bottom the ocean is turbulent and the resultant mixing leads to a neutrally stratified bottom layer. Turbulent closure models have been applied to investigate how the structure of the Benthic Boundary Layer is affected by the flow and the stratification above the layer. / The object of the present research is to analyze how the benthic region affects the dynamics of the forcing flow. More specifically, a numerical model based on the level 2 1/2 closure scheme of Mellor and Yamada is developed to examine the decay of deep mesoscale eddy-like flows. / It is found that the decay of the flow occurs through conversion of kinetic to potential energy and through dissipation by bottom friction. The relative importance of both processes is expressed by the Rossby number (epsilon) = U/fR and by the stratification parameter s = N('2)H('2)/f('2)R('2) (where H is the total depth of the eddy, R the radius, U the velocity scale, N the Brunt-Vaiasala frequency, and f the Coriolis parameter). A larger Rossby number and stratification parameter lead to a larger conversion of kinetic to potential energy, but a smaller mechanical dissipation of the same energy. / Examination of the structure of the Benthic Boundary Layer indicates that a clear distinction should be made between the mixed layer, or the region neutrally stratified, and the Bottom Boundary Layer, or the region where most of the turbulent activity occurs. It is found that the structure of the Bottom Boundary Layer depends also on the magnitude of the flow above the benthic region, but the mixed layer depends also on the sign of the mesoscale activity. Under a cyclonic flow, the mixed layer is defined by vertical advection and it is usually much thicker than the Bottom Boundary Layer. The mixed layer of an anticyclonic flow is the result of both vertical advection and near bottom turbulence, and the ambiguity between the mixed layer and Bottom Boundary Layer is notably reduced. / Source: Dissertation Abstracts International, Volume: 46-06, Section: B, page: 1852. / Thesis (Ph.D.)--The Florida State University, 1985.
| Identifer | oai:union.ndltd.org:fsu.edu/oai:fsu.digital.flvc.org:fsu_75601 |
| Contributors | PEGGION, GERMANA., Florida State University |
| Source Sets | Florida State University |
| Detected Language | English |
| Type | Text |
| Format | 152 p. |
| Rights | On campus use only. |
| Relation | Dissertation Abstracts International |
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