Double-Diffusive Recipes. Part I: Large-Scale Dynamics of Thermohaline Staircases
The article of record as published may be found at http://dx.doi.org/10.1175/JPO-D-13-0155.1 Three-dimensional dynamics of thermohaline staircases are investigated using a series of basin-scale staircase-resolving numerical simulations. The computational domain and forcing fields are chosen to refle...
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ftnavalpschool:oai:calhoun.nps.edu:10945/42132 2024-06-09T07:48:14+00:00 Double-Diffusive Recipes. Part I: Large-Scale Dynamics of Thermohaline Staircases Radko, T. Butlers, A. Flanagan, J.D. Campin, J.-M. Oceanography 2014-05 application/pdf https://hdl.handle.net/10945/42132 unknown Journal of Physical Oceanography, Volume 44, pp. 1269-1284, May 2014. https://hdl.handle.net/10945/42132 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. Article 2014 ftnavalpschool 2024-05-15T00:32:04Z The article of record as published may be found at http://dx.doi.org/10.1175/JPO-D-13-0155.1 Three-dimensional dynamics of thermohaline staircases are investigated using a series of basin-scale staircase-resolving numerical simulations. The computational domain and forcing fields are chosen to reflect the size and structure of the North Atlantic subtropical thermocline. Salt-finger transport is parameterized using the flux-gradient formulation based on a suite of recent direct numerical simulations. Analysis of the spontaneous generation of thermohaline staircases suggests that thermohaline layering is a product of the gamma instability, associated with the variation of the flux ratio g with the density ratio Rr. After their formation, numerical staircases undergo a series of merging events, which systematically increase the size of layers. Ultimately, the system evolves into a steady equilibrium state with pronounced layers 20–50m thick. The size of the region occupied by thermohaline staircases is controlled by the competition between turbulent mixing and double diffusion. Assuming, in accordance with observations, that staircases form when the density ratio is less than the critical value of Rcr ’1:7, the authors arrive at an indirect estimate of the characteristic turbulent diffusivity in the subtropical thermocline. Article in Journal/Newspaper North Atlantic Naval Postgraduate School: Calhoun |
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Naval Postgraduate School: Calhoun |
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ftnavalpschool |
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description |
The article of record as published may be found at http://dx.doi.org/10.1175/JPO-D-13-0155.1 Three-dimensional dynamics of thermohaline staircases are investigated using a series of basin-scale staircase-resolving numerical simulations. The computational domain and forcing fields are chosen to reflect the size and structure of the North Atlantic subtropical thermocline. Salt-finger transport is parameterized using the flux-gradient formulation based on a suite of recent direct numerical simulations. Analysis of the spontaneous generation of thermohaline staircases suggests that thermohaline layering is a product of the gamma instability, associated with the variation of the flux ratio g with the density ratio Rr. After their formation, numerical staircases undergo a series of merging events, which systematically increase the size of layers. Ultimately, the system evolves into a steady equilibrium state with pronounced layers 20–50m thick. The size of the region occupied by thermohaline staircases is controlled by the competition between turbulent mixing and double diffusion. Assuming, in accordance with observations, that staircases form when the density ratio is less than the critical value of Rcr ’1:7, the authors arrive at an indirect estimate of the characteristic turbulent diffusivity in the subtropical thermocline. |
author2 |
Oceanography |
format |
Article in Journal/Newspaper |
author |
Radko, T. Butlers, A. Flanagan, J.D. Campin, J.-M. |
spellingShingle |
Radko, T. Butlers, A. Flanagan, J.D. Campin, J.-M. Double-Diffusive Recipes. Part I: Large-Scale Dynamics of Thermohaline Staircases |
author_facet |
Radko, T. Butlers, A. Flanagan, J.D. Campin, J.-M. |
author_sort |
Radko, T. |
title |
Double-Diffusive Recipes. Part I: Large-Scale Dynamics of Thermohaline Staircases |
title_short |
Double-Diffusive Recipes. Part I: Large-Scale Dynamics of Thermohaline Staircases |
title_full |
Double-Diffusive Recipes. Part I: Large-Scale Dynamics of Thermohaline Staircases |
title_fullStr |
Double-Diffusive Recipes. Part I: Large-Scale Dynamics of Thermohaline Staircases |
title_full_unstemmed |
Double-Diffusive Recipes. Part I: Large-Scale Dynamics of Thermohaline Staircases |
title_sort |
double-diffusive recipes. part i: large-scale dynamics of thermohaline staircases |
publishDate |
2014 |
url |
https://hdl.handle.net/10945/42132 |
genre |
North Atlantic |
genre_facet |
North Atlantic |
op_relation |
Journal of Physical Oceanography, Volume 44, pp. 1269-1284, May 2014. https://hdl.handle.net/10945/42132 |
op_rights |
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. |
_version_ |
1801379868544335872 |