Laboratory experiments on the interaction of a buoyant coastal current with a canyon : application to the East Greenland Current
MetadataShow full item record
This paper presents a set of laboratory experiments focused on how a buoyant coastal current flowing over a sloping bottom interacts with a canyon and what controls the separation, if any, of the current from the upstream canyon bend. The results show that the separation of a buoyant coastal current depends on the current width W relative to the radius of curvature of the bathymetry ρc. The flow moved across the mouth of the canyon (i.e., separated) for W/ρc > 1, in agreement with previous results. The present study extends previous work by examining both slope-controlled and surface-trapped currents, and using a geometry specific to investigating buoyant current–canyon interaction. The authors find that, although bottom friction is important in setting the position of the buoyant front, the separation process driven by the inertia of the flow could overcome even the strongest bathymetric influence. Application of the laboratory results to the East Greenland Current (EGC), an Arctic-origin buoyant current that is observed to flow in two branches south of Denmark Strait, suggests that the path of the EGC is influenced by the large canyons cutting across the shelf, as the range of W/ρc in the ocean spans those observed in the laboratory. What causes the formation of a two-branched EGC structure downstream of the Kangerdlugssuaq Canyon (68°N, 32°W) is still unclear, but potential mechanisms are discussed.
Author Posting. © American Meteorological Society, 2009. 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 39 (2009): 1258-1271, doi:10.1175/2008JPO4028.1.
Showing items related by title, author, creator and subject.
Sutherland, David A.; Pickart, Robert S. (2008-03-12)The subtidal circulation of the southeast Greenland shelf is described using a set of high-resolution hydrographic and velocity transects occupied in summer 2004. The main feature is the East Greenland Coastal Current ...
Shcherbina, Andrey Y.; Gawarkiewicz, Glen G. (American Geophysical Union, 2008-10-18)The combined effect of cooling and wind-driven buoyancy flux (WDBF) on a buoyant coastal current east of Cape Cod is investigated using observations and process-oriented numerical modeling. Theoretical considerations show ...
A coastal current in winter : autonomous underwater vehicle observations of the coastal current east of Cape Cod Shcherbina, Andrey Y.; Gawarkiewicz, Glen G. (American Geophysical Union, 2008-07-28)Evolution of the coastal current structure on the shallow continental shelf east of Cape Cod was studied using autonomous underwater vehicle (AUV) surveys and moored observations during the winters of 2005 and 2006. A ...