Observations of high speed deep currents in the northern Gulf of Mexico

Recent measurements in water depths of 2000 m in the vicinity of the Sigsbe e Escarpment, south of New Orleans, show the presence of recurring high spe ed current episodes, some of which had velocities greater than 85 cm/s only 10 m above the local bottom. In the Gulf of Mexico, currents above about 1 000 m are not locally coupled with the relatively depth-independent current s in the deeper layers. Topographic Rossby waves, with periods of approxima tely 10 to 14 days, appear to control the dynamics of the lower water-colum n.