The characteristics and mechanisms of internal tide dissipation near the bottom of a continental slope areinvestigated by combining high-precision temperature observations with the two-dimensional MITgcm(Massachusetts Institute of Technology General Circulation Model). The fine structure of the temperature field and estimated turbulent dissipation show that bottom-intensifiedturbulent mixing is closely related to temperature fronts with a diurnal period. The mixing peaks particularly in the transitional zones between downslope advection of warmer water and upslope advection of colder water, where turbulent dissipation rates and vertical eddy diffusivities frequently reach their maximum values. Numerical simulations reproduce the observed temperature variability and dissipation characteristics, suggesting that these temperature fronts and associated near-bottom enhancements of turbulent dissipation are primarily generated by the interaction of incident diurnal internal tides with the slope topography. Analysis of the Richardson number field reveals that shear-unstable regions occupy only 18.6% of the domain but account for approximately 67% of the total dissipation, with mean dissipation rates one order higher than those in stable regions. Furthermore, dynamic differences between the upslope and downslope phases of the internal tide induce spatially asymmetric distributions of turbulent dissipation, with critical-supercritical slopes acting as particularly efficient energy sinks during the downslope phase. These results indicate that shear instability generated by nonlinear interactions between internal tides and the continental slope are the dominant mechanism driving localized intense turbulent mixing.
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