How much do tides affect the circulation of the Mediterranean Sea? From local processes in the Strait of Gibraltar to basin-scale effects

The effects of tidal forcing on the exchange flow through the Strait of Gibraltar and the circulation in the near-field region are revisited with a regional numerical model. Also a basin-scale model run is conducted in a first attempt to assess the impact of these local processes on the Western Mediterranean thermohaline circulation. In the Strait of Gibraltar, tides are found to (1) increase the exchange flow volume transport, (2) modify the hydrological properties of Atlantic inflowing waters through the enhancement of mixing, and (3) facilitate the drainage of Mediterranean deep water. In the far-field, the model reveals that these local processes can favor deep convection in the Gulf of Lion. Some thoughts are provided offering possible explanations.