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

2aAO11. Decadal variability in acoustic thermometers interpreted with ocean models.

John Spiesberger

Mark Keller

Dept. of Meteorol. and the Appl. Res. Lab., 512 Walker Bldg., Penn State Univ., University Park, PA 16802

Mark Johnson

Univ. Alaska---Fairbanks, Fairbanks, AK 99775-1080

Harley Hurlburt

Naval Res. Lab., Stennis Space Center, Bay St. Louis, MS 39522

James O'Brien

Florida State Univ., Tallahassee, FL 32306

Travel times of acoustic signals were measured between the bottom-mounted Kaneohe source near Oahu and seven SOSUS stations at 3000--4000-km distance during 1983--1989. The Naval Research Laboratory hydrodynamic eddy resolving model yields changes in travel time whose standard deviations are consistent with the data. The model predicts that between 1981--1993, Rossby waves modify travel times by one second. Mesoscale eddies modify travel times little compared to Rossby waves. The largest Rossby waves are descendants of El Nino. Travel times changes are sensitive indicators of predictable features in the Naval Research Laboratory model. [Work supported by the Strategic Environmental Research and Development Program, managed by the Advanced Research Projects Agency.]