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Oceanology

, Volume 50, Issue 2, pp 166–174 | Cite as

Horizontal convective water exchange above a sloping bottom: The mechanism of its formation and an analysis of its development

  • I. P. ChubarenkoEmail author
Marine Physics

Abstract

The mechanism of the formation of horizontal temperature/density gradients above underwater coastal slopes of natural basins due to heating/cooling from the surface is considered. It is shown that the time required for formation of the gradients is rather small (tens of minutes for a thermocline depth of tens of meters), but the development of the corresponding flows may not be accomplished even in a day long cycle. The time dependence of the horizontal water exchange between the shallow and deep areas is analytically treated. The spatial scale of the problem is the main parameter that defines the resulting quasi-stationary value of the flow rate. The joint analysis of the published field, laboratory, and numerical data of many authors in the range of the above-slope depths of 10−2 m < d < 3 × 102 m (dD, where D is the thickness of the upper thermally active layer of a basin) indicates that the relation between the value of the horizontal quasi-stationary volumetric flow rate and the local depth looks like Q = 0.00l3 × d 1.37 (R 2 = 0.96). The horizontal convective water exchange is shown to be generally two-layered, ageostrophic, and exhibits its maximum flow rate at the end of the slope. The inferences agree well with the field data and conclusions of other authors.

Keywords

Water Exchange Atlantic Meridional Overturning Circulation Slope Bottom Local Depth Horizontal Temperature Gradient 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Pleiades Publishing, Ltd. 2010

Authors and Affiliations

  1. 1.Atlantic Branch of P.P. Shirshov Institute of OceanologyRussian Academy of SciencesKaliningradRussia

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