Coherent ray propagation through a Gulf Stream Ring

Coherent ray‐tracing techniques were applied to describe acoustic propagation through a Gulf Stream Ring 320 km in diameter as measured in 1973. Rays were traced from a fixed source to a fixed receiver 445 km distant incorporating the profile variations of the Ring which had a forward movement of 4 km a day. This anomaly shifted the deep sound channel axis about 400 m and also decreased the minimum sound velocity. These profile variations caused significant changes in the arrival pattern of the ray types and number of cycles. A time history is presented of the relationships between the received signal variations and the passage of the Ring including the effects of the changes in multipath structure.