An inertial model of the interaction of Ekman layers and planetary islands
MetadataShow full item record
KeywordBaroclinic flows; Large-scale motions; Nonlinear dynamics; Ocean circulation; Ocean dynamics; Topographic effects
An adiabatic, inertial, and quasigeostrophic model is used to discuss the interaction of surface Ekman transport with an island. The theory extends the recent work of Spall and Pedlosky to include an analytical and nonlinear model for the interaction. The presence of an island that interrupts a uniform Ekman layer transport raises interesting questions about the resulting circulation. The consequential upwelling around the island can lead to a local intake of fluid from the geostrophic region beneath the Ekman layer or to a more complex flow around the island in which the fluid entering the Ekman layer on one portion of the island's perimeter is replaced by a flow along the island's boundary from a downwelling region located elsewhere on the island. This becomes especially pertinent when the flow is quasigeostrophic and adiabatic. The oncoming geostrophic flow that balances the offshore Ekman flux is largely diverted around the island, and the Ekman flux is fed by a transfer of fluid from the western to the eastern side of the island. As opposed to the linear, dissipative model described earlier, this transfer takes place even in the absence of a topographic skirt around the island. The principal effect of topography in the inertial model is to introduce an asymmetry between the circulation on the northern and southern sides of the island. The quasigeostrophic model allows a simple solution to the model problem with topography and yet the resulting three-dimensional circulation is surprisingly complex with streamlines connecting each side of the island.
Author Posting. © American Meteorological Society, 2013. This article is posted here by permission of American Meteorological Society for personal use, not for redistribution. The definitive version was published in Journal of Physical Oceanography 43 (2013): 1398–1406, doi:10.1175/JPO-D-13-028.1.
Suggested CitationJournal of Physical Oceanography 43 (2013): 1398–1406
Showing items related by title, author, creator and subject.
The dynamic role of ridges in a β-plane channel : towards understanding the dynamics of large scale circulation in the Southern Ocean Wang, Liping (Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 1993-07)In this thesis, the dynamic role of bottom topography in a β-plane channel is systematically studied in both linear homogeneous and stratified layer models in the presence of either wind stress (Chapters 2, 3, 4, and 6) ...
Bio-physical models of oceanic population dynamics : 1994 summer study program in geophysical fluid dynamics Flierl, Glenn R.; Olson, Donald B. (Woods Hole Oceanographic Institution, 1997-11)Bio-Physical Models of Oceanic Population Dynamics was the central theme of the 1994 summer program in Geophysical Fluid Dynamics (GFD) at the Woods Hole Oceanographic Institution. This unusual topic brought together m ...
Liang, Xinfeng; Spall, Michael A.; Wunsch, Carl (John Wiley & Sons, 2017-10-27)Estimates of the global ocean vertical velocities (Eulerian, eddy-induced, and residual) from a dynamically consistent and data-constrained ocean state estimate are presented and analyzed. Conventional patterns of vertical ...