The influence of bottom topography on long Rossby wave propagation in the South Pacific Ocean

This study examines the long wavelength, westward propagating, baroclinic Rossby wave signal from 10 years of sea level anomalies in the South Pacific Ocean. Whereas enhanced sea surface height (SSH)variability in the southwest Pacific is largely attributed to mesoscale eddy activity, previous studies have noted a region of enhanced SSH of long wavelength in the southeast Pacific suggestive of topographically trapped Rossby waves. Energy variability from Radon Transform analysis of the Rossby wave signal suggests that there is interaction with bathymetric features throughout the entire South Pacific Ocean. Variability in the energy of the westward propagating signal suggests topographic steering. Interaction with ridges influences the speed and meridional extent of the variability.