ASA 127th Meeting M.I.T. 1994 June 6-10

2pUW10. A global survey of the impact on acoustic propagation of deep water warm core ocean eddies.

David G. Browning

Raymond J. Christian

Linda S. Petitpas

Naval Undersea Warfare Ctr., New London Detachment, New London, CT 06320

Warm core eddies have been reported throughout the oceans of the world, usually associated with warm boundary currents such as the Gulf Stream. The physical characteristics and impact on acoustic propagation conditions were compared for various eddies at locations ranging from the East Greenland Current to the Tasman Sea. The eddies were found to have some common features such as a conical shape and increased sound speed. On the other hand, the acoustic impact was significantly determined by the sound-speed profile in the adjacent water to the eddy and this was found to vary greatly from site to site. In addition, seasonal secondary sound channels were formed across the eddies at some locations. In general, the greatest acoustic impact of a warm core eddy was for a shallow source and receiver configuration.