Broadband ADCP measurements of the Connecticut River plume front

A broadband ADCP and CTD, mounted aboard a towed platform (TOAD), were used to characterize the front of the Connecticut River plume in Long Island Sound on April 5, 1994. The CTD was at /spl sim/0.75 m and the ADCP estimated velocities in 0.25 m intervals from 1.1 m to the bottom, /spl sim/10 m. Data were processed in 5-s intervals yielding backscatter and bottom-track-referenced absolute velocities. Five crossings of the front, two at near normal angles and three at oblique angles, are discussed. Surface convergence was measured at the front. Vertical velocity was measured on the sound side of the front. Scalar measurements (density and backscatter) indicated that the plume thickened near the front.