This paper presents a five-year global simulation of HYCOM, the HYbrid Coordinate Ocean Model, thatsimultaneously resolves the eddying general circulation, barotropic tides, and baroclinic tides with 32layers in the vertical direction and 1/12.5 (equatorial) horizontal grid spacing. A parameterized topographicwave drag is inserted into the model and tuned so that the surface tidal elevations are of comparableaccuracy to those in optimally tuned forward tide models used in previous studies. The modelcaptures 93% of the open-ocean sea-surface height variance of the eight largest tidal constituents, asrecorded by a standard set of 102 pelagic tide gauges spread around the World Ocean. In order to minimizethe impact of the wave drag on non-tidal motions, the model utilizes a running 25-h average toapproximately separate tidal and non-tidal components of the near-bottom flow. In contrast to earlierhigh-resolution global baroclinic tide simulations, which utilized tidal forcing only, the simulation presentedhere has a horizontally non-uniform stratification, supported by the wind- and buoyancy forcing.The horizontally varying stratification affects the baroclinic tides in high latitudes to first order. The magnitudeof the internal tide perturbations to sea surface elevation amplitude and phase in a large box surroundingHawai’i is quite similar to that observed in satellite altimeter data, although the exact locationsof peaks and troughs in the modeled perturbations differ from those in the observed perturbations.
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