Current Variability on a Narrow Shelf with Large Ambient Vorticity

this paper is the width of the shelf, which is well known to have an impact on the littoral circulation. In the Southern Atlantic Bight, for example, M 2 tidal amplitudes increase with the northward increase of the shelf width from Florida into Georgia, as noted by Redfield [1958]. In that study the shelf is wide, with the shelf break and the western boundary current being located well offshore. However, little appears to be known about the impact of strong adjacent currents on a narrow shelf, the topic of this paper. The continental shelf in the vicinity of Fort Lauderdale, Florida, is narrow and shallow, the shelf break being marked by the "Third Reef," a coral reef only 2.5 km offshore. Depths inside of the reef do not exceed 22 m (Figure 1), and the coastline is quite straight, stretching approximately in the north-south direction (Figure 2a). We analyze here how the circulation on and near the shelf is affected by the presence of the Florida Current (FC) with principally northward velocities exceeding 2 m s #1 at times (Figure 3b