Wind-Driven Currents on the West Florida Shelf

Abstract

Dep. Oceanogr., Florida State Univ., Tallahassee, FL 32306, USA J (Journal-Article) M (Marine) Three weeks of current-meter, wind and sea-level data off Cedar Key, Florida are analyzed. Currents and sea level are found to be coherent with alongshore wind stress in the "synoptic: band ( similar to 0.05-0.25 cycle per day) and to lag it by approximately half a day. Little coherence is found with cross-shelf wind stress. At the inshore mooring (22 m depth) currents are nearly barotropic for these winter 1978 data. The dominant momentum balance in the alongshore direction is between wind and bottom stress. The offshore frictional length scale (Csanady, 1978) is estimated to be 75-100 km, which implies a seaward extent to a depth of about 30 m. At the offshore mooring (44 m depth) there is vertical shear between the currents at 9 and 39 m. The upper cross-shelf component, which is large relative to that at the inshore mooring, is consiste...