Field validation of a semi-spherical Lagrangian drifter

We present the design and field validation for the performance of a Semi-sp herical Lagrangian Drifter (SELD). The SELD is a low-cost, low-technology, home-made alternative to much more expensive commercial Lagrangian drifters . An analysis of the SELD configuration shows that its drag area ratio is a s good as TRISTAR and holey-sock drifters. Field results in a situation of near solid rotation within an oceanic vortex confirm that SELD and holey-so ck drifters have an almost identical behavior.