Study of a mesoscale anticyclonic eddy in the western part of the Gulf of Lion

► We study an observed eddy structure in the western part of the Gulf of Lion during the Latex08 cruise. ► We use ADCP, XBT, SST data and Lagrangian drifters to investigate the observed eddy. ► This coastal mesoscale anticyclonic eddy is elliptic in shape, and baroclinic, limited vertically to the thermocline. ► The coastal eddy can interact with the large scale circulation. ► We propose some mechanisms of eddy generation.