Evaluating the Sensitivity of Tidal Dynamics to Spatial Variation of Bottom Friction Coefficient in the Hormuz Strait

In this research, a modified version of the 3D finite-element hydrostatic model QUODDY-4 is used to assessment of sensitivity of dynamics of the M2 semidiurnal tide to spatial variations of bottom roughness in the Hormuz Strait. This version differs from the original one, as it introduces a module providing calculation of the drag coefficient. Spatial variation of the drag coefficient is calculated using a hydrodynamic approach, which describes the relation between wave friction factor as well as other resistance characteristics and dimensionless parameters like surface Rossby number, Reynolds number for currents and relative inertial frequency. Comparing the results of numerical simulations with observed amplitude and phase values showed that, the model has a good accuracy in reproducing the tidal dynamics in the studied region. The results of this study indicate that the friction coefficient in the Hormuz Strait varies from 0.0006 to 0.004 and is less than its canonical value equal to 0.003, which is usually used in numerical models for tidal predictions. Spatial variation of friction coefficient calculated in this study can be used in numerical tidal predictions in the Hormuz Strait in aim to improve the predictions accuracy.