ASA 129th Meeting - Washington, DC - 1995 May 30 .. Jun 06

1pAO9. Acoustic travel time biases caused by mesoscale eddy.

E. C. Shang

Y. Y. Wang

A. G. Voronovich

CIRES, Univ. of Colorado/NOAA/Environ. Technol. Lab., Boulder, CO 80303

Smaller scale fluctuations can be smooth-out by taking a long range propagation under linearized assumption. But the nonlinearity of the equations relating ocean perturbations to acoustic travel times leads to a bias if the problem is linearized about a range-independent reference state. The travel time t[sub RD] in the range-dependent channel differs from the travel time t[sub RA] through the range-averaged channel. In ray theoretical regime, a warm bias (t[sub RD]t[sub RA]) caused by mesoscale eddy in mode theory regime. [Work supported by ONR, ARPA, and NOAA.]