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arXiv · 1410.1061

Drag coefficient for the air-sea exchange: foam impact in hurricane conditions

Ephim Golbraikh·Yuri M. Shtemler
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Abstract

A physical model is proposed for the estimation of the foam impact on the variation of the effective drag coefficient, C_d, with reference to the wind speed U10 in stormy and hurricane conditions. In the present model C_d is approximated by partitioning the sea surface into foam-covered and foam-free areas. Based on the available optical and radiometric measurements of the fractional foam coverage and the characteristic roughness of the sea-surface in the saturation limit of the foam coverage, the model yields the resulting dependence of C_d vs U10. This dependence is in fair agreement with that evaluated from field measurements of the vertical variation of the mean wind speed.

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Ephim Golbraikh, Yuri M. Shtemler. 2014-10-04. Drag coefficient for the air-sea exchange: foam impact in hurricane conditions. https://arxiv.org/abs/1410.1061

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