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.]