Scattering of the Low-Mode Internal Tide at the Line Islands Ridge

Maha Haji, S.M., 2015
Thomas Peacock, Advisor

The scattering of low-mode internal tides by ocean-floor topography is extensively studied through analytical models and field observations at the Line Islands Ridge (LIR). An existing Green function method is utilized to examine the generation of and scattering of a mode-1 internal tide at realistic transects of the LIR to determine the relative high mode energy flux due to generated and scattered internal tides at the realistic transects.

A method of determining the modal content of an internal wave field is advanced to account for arbitrary stratification and rotation as well as image loss common to oceanographic studies. Its performance is compared to the existing regression method to determine the modal content of internal tides. The results from this comparison are used to inform the analysis of the field observations.

This thesis concludes by examining the modal content of the LIR as determined from measurements taken during the 150-day EXperiment on Internal Tide Scattering (EXITS) NSF field study. The data from three moorings equipped with moored profilers is analyzed to determine the modal content of the southward propagating internal tide before and after it encounters the ridge for evidence of topographic scattering.