Baroclinic vortices over a sloping bottom
LaCasce, Joseph H.
MetadataShow full item record
Nonlinear quasigeostrophic flows in two layers over a topographic slope are considered. The evolution depends on the size of two parameters which indicate the degree of nonlinearity at depth. The first measures the importance of relative vorticity advection and the second of stretching vorticity. Two types of isolated vortex are used to examine the parameter dependence. An initially barotropic vortex remains barotropic only when the first parameter is large, otherwise topographic waves dominate at depth. An Initially surface-trapped vortex larger than deformation scale is baroclinically unstable when the second is large, but is stabilized by the slope otherwise. Both parameters are also relevant to cascading geostrophic turbulence. If the stretching parameter is large, a "barotropic cascade" occurs at the deformation radius (Rhines, 1977) and the cascade "arrests" when the relative vorticity parameter is order unity. If small, layer coupling is hindered and the cascade is arrested at the deformation scale, with the flow dominated by isotropic surface vortices. In both cases, the distinction between vortices and waves is transparent when viewing potential vorticity. It is more difficult to identify waves and vortices from the streamfunction fields, because the waves are present in both layers.
Submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy at the Massachusetts Institute of Technology and the Woods Hole Oceanographic Institution September 1996
Suggested CitationThesis: LaCasce, Joseph H., "Baroclinic vortices over a sloping bottom", 1996-09, DOI:10.1575/1912/2457, https://hdl.handle.net/1912/2457
Showing items related by title, author, creator and subject.
McLellan, Tracy (Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 1976-05)Osteology and myology of the head of 21 species of macrourids and two closely related species are described. A general model of the mechanics of the macrourid head during feeding has been developed based on the ...
Rodenbusch, George (Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 1978-08)A linearized theory for the response of a circular pendulum spar in 2-dimensional waves and a uniform current is developed. The linear forces on the cylinder are predicted using an approximate potential flow theory for ...
White, Helen K. (Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 2006-02)To provide a new perspective on the fate of both natural organic matter and hydrophobic organic contaminants (HOCs) in marine sediments, we have investigated the relationship between radiocarbon (14C) age and the different ...