Experimental Investigation of the North Brazil Current Rings During Their Interaction with the Lesser Antilles

Interaction of the North Brazil Current Rings (NBCR) with the Lesser Antilles Arc and their penetration into the Caribbean Sea was investigated by laboratory experiments. Self-propagating cyclonic vortices were made with barotropic fluid by one of two methods: suction and electromagnetic. The parameters causing the reflection, destruction and penetration of the rings into the Caribbean Sea were as follows: The Rossby number associated with the vortex, the width of the strait between islands, the incidence angle with the barrier, and the velocity of translation and intensity of interaction with the barrier. The principal observations were made by lagrangian measurements, using particle image velocimetry. It is concluded that the formation of bigs rings within the Caribbean Sea can be attributed to the interaction of vestiges of the NBCR with the chain of islands at the Antilles.