Impacts of Potential Sea-Level Rise on Tidal Dynamics in Khor Abdullah and Khor Al-Zubair, Northwest of Arabian Gulf

Abstract

According to recent studies, sea-level rise (SLR) not only increases the coastal flooding probability but also may change the characteristics of tidal systems in coastal waterbodies. To investigate such changes in Khor Abdulla and Khor Al-Zubair, a two-dimensional depth-averaged model was applied. The calibration and validation were performed through the comparison of model results with measurements of water level and flow velocities in particular sites within model domain. SLR scenarios of 0.25, 0.5, 0.75, and 1 m were simulated. The simulation results indicate that the response of the principal tidal constituents was spatially nonuniform and exhibited a nonlinearity with SLR scenarios. However, the M2 amplitude decreases in most locations with SLR, with the most reduction occur in the upper reaches of the study area, while S2 and N2 amplitudes display a slight increase in a most sites along KA and KZ. Similarly, the amplitudes of K1 and O1 experience to a notable decrease in most locations when sea level rises. Additionally, there is a reduction in constituents’ phases with SLR scenarios. The decrement in constituents’ phases indicates that these waves will arrive earlier when sea level rises due to the nature of tidal wave propagation and their dependency on the water depth. Furthermore, the magnitude of the tidal currents also displays a spatially irregular response to SLR with a noticeable shift in the time of peak flood and ebb current velocities in many locations, while the direction of the currents remains unchanged at most sites of the study area.