Laboratory Studies of Density Increase on Shelves

• Main Author: Whitehead, John A.
• Other Authors: WOODS HOLE OCEANOGRAPHIC INSTITUTION MA
• Format: Text
• Language: English
• Published: 2001
• Subjects: Physical and Dynamic Oceanography; *DENSITY; *LABORATORY TESTS; *OCEAN BASINS; *BUOYANCY; *FLUID MECHANICS; VELOCITY; STEADY STATE; RATIOS; INTERACTIONS; LAYERS; WATER; RATES; EQUILIBRIUM(GENERAL); REGIONS; SURFACES; FRESH WATER; WIND DIRECTION; THINNESS; BEHAVIOR; FLOW; PLUMES; FLUID DYNAMICS; ROTATION; FRICTION; STRATIFICATION; WATER MASSES; BASINS(GEOGRAPHIC); HYSTERESIS; WAVES; COLLAPSE; EDDY CURRENTS; SEA ICE; VORTEX GENERATORS; STEADY FLOW; SALT WATER; FROUDE NUMBER; SHELF BASIN; CONTINENTAL SHELF; Arctic; Sea ice
• Online Access: http://www.dtic.mil/docs/citations/ADA398444; http://oai.dtic.mil/oai/oai?&verb=getRecord&metadataPrefix=html&identifier=ADA398444

Four laboratory experiments and theories were developed. All have application to the Shelf Basin interaction region and elsewhere. Experiments had a plume of salt water flowing down a slope in a rotating basin filled with fresh water. Results collapse to a diagram showing that the ratio of flow speed to wave speed (Froude number) is the main criterion for waves. Mixing substantially increases with rotation rate. Second, a theory describes the effects of density stratification on the sinking of dense water. A thin surface layer of fresher water (arctic halocline) produces multiple equilibrium behavior when cooled from above. Friction from sea ice enhances hysteresis. Exploratory experiments were started. Third, free surface flows over obstacles in a channel were analyzed and observed. Some parameters allow two steady flow states. An intermediate state is discovered. Fourth, vortex generation is produced in a current of dense water descending a slope and encountering obstacles. Experiments produce the geometry of the Chukehi Sea shelf. Eddy formation exists for select parameters. All experiments indicate that ocean dynamics in the Shelf-Basin Interactions region is complex, with eddy formation, uneven mixing, and sudden water mass formation typical. --Original contains color plates: All DTIC reproductions will be in black and white.