Coastal Hydrodynamics and Circulation Exchange Between the Arabian Gulf and the Sea of Oman

The Arabian Gulf (Persian Gulf) and the Gulf of Oman are two basins, physically linked but comprising different hydrodynamic features. The shape of the basins, the weather, and the exchange through the Strait of Hormuz all affect circulation in the system. This review synthesizes current knowledge of hydrodynamic processes leading to water circulation in both basins, including wind forcing, density-driven exchange, tidal dynamics, and mesoscale changes. The Arabian Gulf has shallow depths, intense evaporation, and limited exchange, which promote hypersaline conditions, long residence times, and greater sensitivity to environmental stress. In comparison, the Gulf of Oman has a deeper, more exposed system, governed by monsoon-driven circulation, upwelling, and mesoscale processes. The present review highlights how various hydrodynamic regimes influence stratification, changes in temperature and salinity, and exchange processes, with direct impacts on nutrient transfer, oxygen delivery, and ecosystem dynamics. An important control point, the Strait of Hormuz, connects the Arabian Gulf and the Gulf of Oman. This review also stresses the importance of observational data and modeling capacity, as well as their limitations, for subsurface processes and connections across scales. It also provides an inclusive assessment of hydrodynamics and water circulation in the two basins. Moreover, it underscores the need for coordinated observational and modeling approaches to improve understanding and enhance management of these globally sensitive aquatic systems.