A laboratory model of vertical ocean circulation driven by mixing
MetadataShow full item record
A model of deep ocean circulation driven by turbulent mixing is produced in a long, rectangular laboratory tank. The salinity difference is substituted for the thermal difference between tropical and polar regions. Freshwater gently flows in at the top of one end, dense water enters at the same rate at the top of the other end, and an overflow in the middle removes the same amount of surface water as is pumped in. Mixing is provided by a rod extending from top to bottom of the tank and traveling back and forth at constant speed with Reynolds numbers >500. A stratified upper layer (“thermocline”) deepens from the mixing and spreads across the entire tank. Simultaneously, a turbulent plume (“deep ocean overflow”) from a dense-water source descends through the layer and supplies bottom water, which spreads over the entire tank floor and rises into the upper layer to arrest the upper-layer deepening. Data are taken over a wide range of parameters and compared to scaling theory, energetic considerations, and simple models of turbulently mixed fluid. There is approximate agreement with a simple theory for Reynolds number >1000 in experiments with a tank depth less than the thermocline depth. A simple argument shows that mixing and plume potential energy flux rates are equal in magnitude, and it is suggested that the same is approximately true for the ocean.
Author Posting. © American Meteorological Society, 2008. 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 38 (2008): 1091-1106, doi:10.1175/2007JPO3805.1.
Suggested CitationArticle: Whitehead, John A., Wang, Wei, "A laboratory model of vertical ocean circulation driven by mixing", Journal of Physical Oceanography 38 (2008): 1091-1106, DOI:10.1175/2007JPO3805.1, https://hdl.handle.net/1912/4043
Showing items related by title, author, creator and subject.
Metrics of hurricane-ocean interaction : vertically-integrated or vertically-averaged ocean temperature? Price, James F. (Copernicus Publications on behalf of the European Geosciences Union, 2009-05-05)The ocean thermal field is often represented in hurricane-ocean interaction by a metric termed upper Ocean Heat Content (OHC), the vertical integral of ocean temperature in excess of 26°C. High values of OHC have proven ...
Thermohaline structure, ageostrophic vertical velocity fields and phytoplankton distribution and production in the northeast Atlantic subtropical front Mourino, Beatriz; Fernandez, Emilio; Alves, Mario (American Geophysical Union, 2004-04-21)Two oceanographic cruises were carried out in the Azores Current/Subtropical Front region in July 1997 and April 1999 to study the seasonal and mesoscale spatial variability in the relationship between the hydrodynamic ...
Young, William R. (Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 1981-08)This thesis consists of three loosely related theoretical studies. In chapters 1 - 3 the physical mechanisms which determine the three dimensional structure of the currents in the Sverdrup interior of a wind-driven gyre ...