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Title: Marginal Instability and the Efficiency of Ocean Mixing
The mixing efficiency of stratified turbulence in geophysical fluids has been the subject of considerable controversy. A simple parameterization, devised decades ago when empirical knowledge was scarce, has held up remarkably well. The parameterization rests on the assumption that the flux coefficient Γ has the uniform value 0.2. This note provides a physical explanation for Γ = 0.2 in terms of the “marginal instability” property of forced stratified shear flows, and also sketches a path toward improving on that simple picture by examining cases where it fails.  more » « less
Award ID(s):
1830071 1355768 1851520
Author(s) / Creator(s):
Date Published:
Journal Name:
Journal of physical oceanography
Page Range / eLocation ID:
Medium: X
Sponsoring Org:
National Science Foundation
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