Abstract: We present a thorough Lagrangian analysis of the statistics of surface velocities in the Gulf of Guinea, based on more than twenty years of drifter data. After subtracting the mean Eulerian velocity field and normalizing by the local standard deviation, we compute the probability density functions (PDFs) of the zonal and meridional components of the relative velocities. The distributions obtained display systematic deviations from normality, with heavy tails and moderate asymmetry, suggesting the influence of intermittent energetic events, probably related to mesoscale eddy activity. The analysis of Lagrangian autocovariance functions highlights anisotropy in the integration times, with longer persistence in the zonal direction, in line with the dynamics of equatorial currents. Finally, segmenting trajectories into 10-day segments confirms the robustness of these statistical signatures at the meso scale, supporting the hypothesis of a dynamics dominated by non-Gaussian coherent structures.
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