ASA 124th Meeting New Orleans 1992 October

3aAO12. Parametric models for acoustic convergence zone variations.

K. P. Bongiovanni

W. L. Siegmann

Rensselaer Polytechnic Inst., Troy, NY 12180

D. S. Ko

Inst. for Naval Oceanogr., Stennis Space Center, MS 39529

A model that is designed to provide feedback for assessment and improvement of ocean prediction models is presented. Typical prediction model temperature field output is assumed to be modeled statistically and parametrically. An objective is to relate resulting ocean environmental parameters to some natural acoustic metrics corresponding to measurable features of the received field. The approach uses a canonical sound-speed profile [J. C. Miller, J. Acoust. Soc. Am. 71, 859--862 (1982)] which has closed-form ray solutions in a range-independent medium. By incorporating the environmental parameters into the sound-speed profile and employing the ray geometry for a shallow acoustic source, expressions for convergence zone widths and ranges are developed. A sensitivity examination shows that thermocline scale is the dominant factor for convergence zone variabilities. Implications of the relationships for model assessment will be discussed. [Work supported by INO.]