Observations of a Tropical Instability Vortex^*

Abstract

An upper-ocean vortex associated with tropical instabilities was observed during fall 1990 at 140W in the shear region between the Pacific South Equatorial Current and the North Equatorial Counter current. The velocity and thermohaline structures of the vortex were mapped in three dimensions using hydrography, acoustic Doppler current measurements, drifters, and satellite infrared images.