Gulf Stream Eddies in the Western North Atlantic.

The results of 60 thermal structure studies of the Gulf Stream system from Cape Hatteras to 60 W between November 1969 and May 1973 are described. During this period sixteen Gulf Stream eddies were studied for periods of up to 8 months. The data indicated that both cyclonic and anticyclonic Gulf Stream eddies are an integral part of the thermal structure of the area, forming eastward of 70 W from unstable Gulf Stream meanders. Eddy sizes increase with eastward formation and once separated from the Gulf Stream maintain thermal and velocity structure efficiently. Cyclonic eddies were observed to translate either westward in a spiraling path or on a more direct path to the southwest. Westward moving eddies coalesced with the Gulf Stream within five months. Cyclonic eddies not influenced by the Gulf Stream slowly subsided in Sargasso Water losing surface identity and drifting out of the survey area. Anticyclonic eddies translate westward along the seaward edge of the Continental Slope.