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arXiv · 1406.5928

Identify the diapycnical eddy diffusivities by salt fingers and turbulence with vertical microstructure measurements

Liang Sun
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Abstract

Diapycnical eddy diffusivities are formulated from physical relations according to a simple fact that the different formulas are identical for the same parameter. It is found that the dispassion ratio \Gamma is a crucial parameter. When it is above a critical value (about 0.2), the flow is salt finger type; otherwise, it is turbulence. All the density ratio $R_\rho=1/(1-\Gamma^2)$, eddy flux ratio $\gamma=1/(1+\Gamma)$, and eddy diffusivity ratio $R_k=1-\Gamma$ are simply dependent on the dispassion ratio gamma \Gamma. We apply these relations to the measurement data in the western tropical Atlantic Ocean. The effective diapycnal diffusivity is $0.96*10^{-4} m^2/s$ that agrees quite well with the observation from 0.8 to $0.9*10^{-4} m^2/s$ by tracer.

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Liang Sun. 2014-06-23. Identify the diapycnical eddy diffusivities by salt fingers and turbulence with vertical microstructure measurements. https://arxiv.org/abs/1406.5928

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