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Dispersion of tracers in the deep ocean

Published online by Cambridge University Press:  20 April 2006

Ronald Smith
Ronald Smith
Affiliation:
Department of Applied Mathematics and Theoretical Physics, University of Cambridge
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Abstract

Exact solutions are used to contrast the behaviour of vertical dye streaks and of point discharge in the deep ocean. After a few inertial periods the growth of the contaminant cloud in both cases can be modelled by a diffusion equation with slowly varying coefficients. However, the apparent long-term diffusivity for the dye streak can be as much as three times as large as the horizontal diffusivity for the point discharge, depending upon the precise time of release. This anomalously large rate of spreading for the dye streak can persist for several weeks until sufficient time has elapsed for vertical diffusion over the vertical lengthscale of the dominant inertial- frequency waves.

Type
Research Article
Information
Journal of Fluid Mechanics , Volume 123 , October 1982 , pp. 131 - 142
Copyright
© 1982 Cambridge University Press

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