In the Mediterranean Sea, you're never far from a coast. This, and the very complex shape of those coasts make the currents there quite complicated (and its scheme is still in debate). Coastal dedicated data thus can help a better knowledge of the Mediterranean.  In the Gulf of Lion, South of France, a current, the Liguro-provencal current, usually follows the continental shelf from Marseille to Cataluña. However, when winds blow northwards, the current can intrude on the shelf. 

Classical altimetry data do not fully track such intrusions, because the data are usually removed from "open-ocean" dedicated datasets since they are less reliable too close to the coast. However, research is ongoing, and new datasets provided in order to fill this gap as best as possible. 

Saral enables to get closer to the coasts, due to the use of the Ka band. And, in the future, SWOT should get a much finer picture of such areas.