Decay of a Near-Inertial Wave

Abstract

The decay of a downward propagating near-inertial wave was observed over four days. During this short period, the energy of the near-inertial wave decreased by 70%. The shear layers produced by the wave were regions of enhanced turbulent dissipation rates. The authors estimate that 44% of the observed change in the near-inertial energy was lost to turbulence. Estimates of the wave energy lost at the survey site due to the wave propagating out of the region were smaller. Energy lost by horizontal advection of the wave out of the survey region was more difficult to estimate; the horizontal extent of the near-inertial energy was unknown. Advection could account for more than half of the observed energy lost. However, the authors did not detect the near-inertial wave during a 40 km?40 km ADCP survey after completing the six-day station.