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Frontogenesis in gravity-driven flows with non-uniform density gradients

Published online by Cambridge University Press:  26 April 2006

Anthony Kay
Affiliation:
Department of Mathematical Sciences, Loughborough University of Technology, Loughborough, Leicestershire, LE11 3TU, UK

Abstract

A horizontal density gradient may be steepened to form a front if the horizontal flow which it drives is convergent. This convergence may be caused by an initial nonlinearity in the density gradient (as described by Simpson & Linden 1989). A quadratic density profile is analysed to illustrate the mechanism, and it is shown how the flow and the density profile interact to intensify and concentrate the front near a horizontal boundary. Linear and curved density profiles in a container of finite length are also studied: the most favourable location for frontogenesis is found to be where the flow emerges into a region of significant curvature after passing through a maximum of the density gradient.

Type
Research Article
Copyright
© 1992 Cambridge University Press

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