Double-Diffusive Convection
Authors
Radko, Timour
Subjects
Advisors
Date of Issue
2008
Date
Publisher
WHOI
Language
Abstract
Even in systems with a negative vertical density gradient, instability is possible if the density is controlled by two components (e.g. temperature T and salinity S) that diffuse at different rates [24]. In the oceans, temperature diffuses approximately 100 times faster than salt, and so many regions of the ocean are potential candidates for so-called “double-diffusive instability”. Doubly-diffusive effects were observed by several authors before Stern [24] explained the physical mechanism responsible. Jevons [4] and Ekman [1] had previously observed instability at the interface between temperature stratified water and an overlying layer of denser fluid, but neither recognised the significance of double-diffusion. Later, Stommel et al. [28] showed that a “perpetual salt fountain” can arise when a tube is inserted vertically through the interface between a layer of warm, salty water overlying cold, fresh water. The fountain persists until the system becomes well mixed. This experiment has recently been realised on an industrial scale [29]. There are two forms of double-diffusive instability, referred to as “salt fingers” and “diffusive convection”.
Type
Conference Paper
Description
The article of record as published may be found at https://darchive.mblwhoilibrary.org/handle/1912/2803
Series/Report No
Department
Oceanography
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NPS Report Number
Sponsors
Funding was provided by the National Science Foundation under grant OCE-0325296 and by the Office of Naval Research, Processes and Prediction Division, Physical Oceanography Program under grant N00014-07-10776
Funder
Format
Citation
Radko, Timour. Double-diffusive convection. 2008 Program of Study: Perspectives and Challenges in GFD, WHOI-2009-02.
Distribution Statement
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This publication is a work of the U.S. Government as defined in Title 17, United States Code, Section 101. Copyright protection is not available for this work in the United States.