Small-scale turbulent diffusion is numerically simulated in relation to its time variability dependent on tidal current. From time series of 3D (3-dimensional) velocity and temperature measured at the depth of 2000 m, main constituents of internal tides are extracted. Wavenumbers of eddies, the scale of which is O (102) m, are determined by Taylor’s frozen eddy hypothesis with time-varying tidal speed taken as advection velocity. Large eddy simulation was applied to generate turbulence numerically by forcing the measured low-wavenumber components in the computational domain. The result shows that the energy dissipation rate varies in time, ranging from O (10−11) to O (10−7) m2 s−3. These values of energy dissipation correspond with vertical diffusivity of 10−6 to 10−4 m2 s−1 in this area, with temporal average value of 6.9 × 10−5 m2 s−1.

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