Wind Stress Direction and the Alongshore Pressure Gradient in the Middle Atlantic Bight

Abstract

We find that the alongshore transport in winter calculated using a circulation model based on Ekman and geostrophic dynamics (Csanady, 1976) for a shelf region similar to the Middle Atlantic Bight is sensitive both to the alongshore component of the wind stress and the alongshore pressure gradient. If the total alongshore transport in the region remains uniform along the shelf at −2.5 × 105 m3 s−1 (positive poleward) as indicated by current meter measurements, our calculations show that the alongshore pressure gradient must decrease from 1 × 10−3 Pa m−1 off Montauk Point to zero south of Cape Henry, as a consequence of the change in orientation of shelf to wind stress.