Subsurface currents off Cape Hatteras

Abstract

In October 1962, direct current measurements at depths of 800 m to 2500 m beneath the zone of swiftest surface currents near Cape Hatteras revealed a subsurface flow to the south. Analyses of temperature-salinity and dissolved oxygen distributions indicate that the immediate source of the southward flowing water was the region east of Cape Hatteras between the Gulf Stream and the Continental Slope. These measurements seem to affirm that continuity exists between the deep westward flow observed in the Slope Water Region by Volkmann and the southward flow east of Cape Romain, near 33°N, reported by Swallow and Worthington. The geostrophic volume transport of the southward flow was between 4 million and 12 million m 3/sec. The surface of zero axial velocity was at a depth of about 500 m at the left side of the region of swift surface current (inshore), and deepened rapidly in the offshore direction.