Dynamics of downwelling in an eddy-resolving convective basin
Spall, Michael A.
MetadataShow full item record
The mean downwelling in an eddy-resolving model of a convective basin is concentrated near the boundary where eddies are shed from the cyclonic boundary current into the interior. It is suggested that the buoyancy-forced downwelling in the Labrador Sea and the Lofoten Basin is similarly concentrated in analogous eddy formation regions along their eastern boundaries. Use of a transformed Eulerian mean depiction of the density transport reveals the central role eddy fluxes play in maintaining the adiabatic nature of the flow in a nonperiodic region where heat is lost from the boundary current. The vorticity balance in the downwelling region is primarily between stretching of planetary vorticity and eddy flux divergence of relative vorticity, although a narrow viscous boundary layer is ultimately important in closing the regional vorticity budget. This overall balance is similar in some ways to the diffusive–viscous balance represented in previous boundary layer theories, and suggests that the downwelling in convective basins may be properly represented in low-resolution climate models if eddy flux parameterizations are adiabatic, identify localized regions of eddy formations, and allow density to be transported far from the region of eddy formations.
Author Posting. © American Meteorological Society, 2010. 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 40 (2010): 2341–2347, doi:10.1175/2010JPO4465.1.
Showing items related by title, author, creator and subject.
Marchal, Olivier (2006-04-25)The 'Sandström theorem' as interpreted by Jeffreys (1925) is that in a flow maintained by a temperature difference, the pathline from the cold region to the warm region must lie below the return path. A formal demonstration ...
Malkus, Willem V. R.; Mellor, Florence K. (Woods Hole Oceanographic Institution, 1981-11)Reexploring convection and its various transitions to chaotic behavior were the central themes of GFD 1981. Our principal lecturer, Dr. Edward A. Spiegel, provided both a rich historical picture and stimulating hours at ...
The influence of convection on large-scale circulations : 1988 Summer Study Program in Geophysical Fluid Dynamics Flierl, Glenn R.; Goulart, Pamela J. (Woods Hole Oceanographic Institution, 1989-07)The topic for the 30th Geophysical Fluid Dynamics Summer Program was "The Influence of Convection on Large- Scale Motions." The principal lecturer, Kerry Emanual, presented the essential elements of dry convection, ...