3D Numerical Modelling of Shallow and Deep Water Currents in the Persian Gulf

A 3D current and water level forecasting system is developed for the whole Persian Gulf in this study, in order to offer a reasonable response for the needs to provide a better understanding of coastal and gulf-scale hydrodynamic processes in this important body of water. There are a couple of research attempts published during the past decades on the hydrodynamics and circulation of the Persian Gulf; however, most of them were concentrated on the coastal and relatively shallow water areas and presented reasonable results. Hence, this study aims to improve model performance in deep water areas while the accuracy of tidal and wind-driven current parameters in shallow water results is acceptable. The most important driving forces, including tides and surface winds, are taken into consideration in simulations, in order to provide relatively accurate estimations of hydrodynamic parameters in the Persian Gulf.     For water level and current three-dimensional simulations, FVCOM numerical open-source model is applied and run for some time periods in which field observations are available for both current specifications and water levels in the Persian Gulf. The open boundary data are adopted from OTPS global model and the input wind field data are applied from WRF wind modeling over the whole body of water. The model results were calibrated for a number of parameters selected in an extensive sensitivity analysis program and optimum values are selected for the under-study parameters. A comprehensive set of field measurements is collected, whose main objective is to provide sufficient and reliable input data for current simulations in the Persian Gulf in both deep and shallow areas. The collected survey parameters are mainly focused on: vertical profiling of current speed and direction; mid‐depth current speed and direction measurements; tidal (water level) measurements; and wind measurements. The data covers a wide range of spatial distribution in the Persian Gulf, including near-shore and offshore areas as well as a wide range of water depth values.     In this study, the obtained water level and current model results are verified against collected field observations, both in shallow and deep water areas and near-shore and offshore regions. Consequently, the optimum settings for obtaining accurate model results in both shallow and deep water areas are reported. The results of this research are of great help to understand the hydrodynamics of the Persian Gulf and provide a basis for more accurate estimations of forecasted current and water level parameters over the study area.