What can satellite surface velocity observations bring in the Mercator system that altimetry observations cannot?

Isabelle Mirouze1, Elisabeth Rémy2, Giovanni Ruggiero3, Mathieu Hamon2, Jean-Michel Lellouche2, Gérald Dibarboure4 and Yannice Faugere4, (1)Freelance consultant for Mercator Ocean International, Toulouse, France, (2)Mercator Ocean International, Toulouse, France, (3)Mercator Océan International, Toulouse, France, (4)CNES French National Center for Space Studies, Toulouse, France