Hydrodynamics of the Strait of Gibraltar : A Review of Numerical Advances
The Strait of Gibraltar is a natural laboratory for studying high-resolution ocean dynamics, where stratified exchange flows, hydraulic controls, and tidal forcing interact in a highly nonlinear system. Over the past two decades, a combination of advanced numerical modeling and observational campaigns has provided key insights into the fundamental physics of this critical gateway between the Atlantic and Mediterranean.
This talk will review major advances in our understanding of Gibraltar dynamics, focusing on the interplay between mean exchange flows, tidal forcing, and their broader climatic implications. The transition between submaximal and maximal exchange regimes, controlled at Camarinal Sill and Tarifa Narrows, has been extensively studied through both two-layer and three-layer hydraulic theories. The role of tides in enhancing mixing and modulating interfacial layer properties has been highlighted by both observational and numerical studies, revealing the impact of semidiurnal tidal forcing in generating internal bores and modifying water mass characteristics. The large-scale influence of Gibraltar dynamics extends beyond the strait itself, shaping the Mediterranean thermohaline circulation and affecting deep water formation processes. Climate-driven variations in Mediterranean stratification and salinity could further alter the exchange regime, with significant consequences for basin-scale circulation.
Advancements in numerical modeling have played a crucial role in refining our understanding of these processes. High-resolution σ-coordinate and z-level models, two-way nested grid techniques, and recent nonhydrostatic approaches have significantly improved the representation of fine-scale processes such as internal wave generation and mixing. These developments are particularly relevant for the MOIRAI (Multiscale Ocean Models and Information for Climate Risk Assessment and Impact Mitigation) project, which integrates high-resolution ocean modeling into the broader framework of Destination Earth (DE) and the European Digital Twin of the Ocean (DTO). The Strait of Gibraltar serves as a key benchmark for validating new modeling approaches that will ultimately contribute to a more accurate representation of Mediterranean-Atlantic connectivity in climate simulations.
By synthesizing these results, this talk will highlight both the current state of knowledge and the open questions that need to be addressed to advance our predictive capabilities in a changing climate.
Contact Eletta Negretti for more information or to schedule a discussion with the seminar speaker.