THE STRUCTURE AND PROPAGATION OF A GULF-STREAM FRONTAL EDDY ALONG THENORTH-CAROLINA SHELF BREAK

The Frontal Eddy Dynamics (FRED) experiment, conducted offshore North Carolina between Cape Fear and Cape Hatteras, included a multiplatform intensive survey phase in May 1987. The intensive phase data set incl udes satellite infrared imagery, aircraft- and shipboard-deployed expe ndable bathythermographs, moored current meters and thermistors, and s atellite-tracked drifting buoys. These observations are used to examin e the structure and propagation of Eddy Abbott, the most extensively s urveyed frontal eddy in this study. The analysis includes the use of a frontal eddy feature model to calculate the surface circulation and p ropagation characteristics of Eddy Abbott's cold dome from the buoy tr ajectories. The observations and analyses presented are unique in that Eddy Abbott is the first Gulf Stream frontal eddy seeded with trackin g buoys to be followed beyond Cape Hatteras. Previously, frontal eddie s were assumed to be sheared apart as they approached the confining to pography of Cape Hatteras, leaving the near surface nutrient rich wate rs of the cold dome stranded on the North Carolina shelf. The in situ tracking data provided by the buoys indicate that rather than being st randed, Eddy Abbott's cold dome accelerates, propagating out of the So uth Atlantic Bight beyond Cape Hatteras.