Deep ADCP Velocity Measurements in the Gulf Stream

Abstract

This paper presents observations of the velocity structure from two transects across a Gulf Stream meander near 37°N, 68°W. Data were collected with a vessel-mounted 75-kHz acoustic Doppler current profiler (ADCP) to a depth of about 700 m. The transducer of this ADCP is protected by a 70-min-thick low-density polyethylene window. The paths of the transcends were chosen based on satellite images collected a few days prior to the transects. The velocity measurements were found to be consistent with the satellite images and with concurrent CTD (conductivity, temperature, and depth) measurements made during the first transect. The maximum speeds observed near the surface were about 2.1 m s?1, and currents at the 600-m depth were as high as 1 m s?1.