Acoustic measurements of internal wave rms displacement and rms horizontal current off Bermuda in late 1983

We use acoustic pulse travel times to measure rms internal wave currents and depth‐ and time‐dependent rms internal wave displacements west of Bermuda in August and September 1983. Displacement energy levels at depth ≲ 200 m are close to the standard Garrett‐Munk (GM) level, while displacement energy levels in the depth range 600–900 m are about one‐half GM. These levels are constant in time to ∼30% over the 6 week data period. Current energy levels in the depth range 600–900 m are nearly 5 times higher than would be inferred from a GM model scaled to the observed displacements, probably indicating that near‐inertial motions were much stronger than in a GM spectrum. These measurements are consistent with other in situ observations, if a general picture is formed of WKBJ‐scaling violation of about a factor of 2 for displacements, and a strong non‐GM inertial peak in horizontal current spectra.