The Arctic Ocean Tides
Previous tidal simulations for the Arctic Ocean were made using structured-grid finite-difference models. Highly referenced works are K&P [1993, 1994 and 1995] and Padman and Erofeeva [2004] (hereafter P&E). K&P developed a two-dimensional (2-D) (vertically-averaged) fully nonlinear barotropic Arctic tidal model with sea ice. With a uniform horizontal resolution of 13.89 km and proper parameterization of the bottom friction, this model provided a reasonable simulation of tidal elevation around the Arctic Ocean and described tidal effects in the sea ice cover. The 2-D assumption and horizontal resolution specified in the K&P model, however, limit its application to resolve the 3-D current features and complex tidal energy exchange between the Arctic and Atlantic Ocean through the Canadian Archipelago. P&E introduced a 2-D linear tidal model (AODIM-the Arctic Ocean Tide Inverse Model) to assimilate the tidal elevation in the Arctic Ocean by computing the inverse solution with all available tidal gauge data. With a horizontal resolution of 5 km, the inverse assimilated tidal elevation shows a better match with observations with smaller overall standard deviation errors. In addition to the 2-D limitation, the linear assumption used in P&E, however, makes this model incapable of resolving residual currents and tide-induced water transports in coastal regions where the interaction of tidal currents with topography is highly nonlinear. Although P&E‘s horizontal grid spacing is ~3 times smaller than that in K&P‘s model, it is still insufficient to resolve the complex geometry within the Canadian Archipelago.
To satisfy the need for an improved model for Arctic Ocean research, we have applied AO-FVCOM to simulate the tides in the barotropic and stratified ice-free Arctic Ocean including Baffin Bay and Hudson Bay/Strait, respectively. Geometrical flexibility of the AO-FVCOM grid allows us to construct meshes without restriction from the meridional convergence of latitude and longitude and any need for “grid rotation”. The singularity at the North Pole is removed by using a spherical-polar stereographic projection nested grid at the pole. The model evaluation was made by comparing it with observational data and presently available tidal models in the Arctic Ocean.
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Animation of Semidiurnal Tidal Elevation and Near-surface Tidal Currents The semidiurnal tides are relatively small in the deep Arctic basins and larger in the Hudson Strait/Bay, southern Baffin Bay, the Denmark Strait west of Iceland, and the White Sea. Numerous amphidromic points occur along (or near to) the coast, indicating that the semidiurnal tidal phases at two very close locations can differ significantly. The M2 tidal motion around Iceland and Spitsbergen Island are characterized by the clockwise round-island wave. Click the play button on the right to view the full size of the animation |
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Enlarged View of M2 Tidal Elevation and Near-surface Tidal Current in Canada Archipelago Click the play button on the right to view the full size of the animation |
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Animation of Diurnal Tidal Elevation and Near-Surface Tidal Currents Click the play button on the right to view the full size of the animation |
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Enlarged View of Diurnal Tidal Elevation and Near-surface Tidal Currents in Canadian Archipelago Click the play button on the right to view the full size of the animation |
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Enlarged View of Diurnal Tidal Elevation and Near-surface Tidal Currents in Baffin Bay Click the play button on the right to view the full size of the animation |
| Tidal Comparison Tables | |||
| M2 tide | S2 tide | O1 tide | K1 tide |