Characterising the Semidiurnal Tide of the Coral and Tasman Seas

Abstract: 

The spatial structure of the semidiurnal internal tide in the Coral and Tasman Seas is characterised using observational data from expendable bathythermographs, Argo floats and unmanned autonomous gliders. Using a combination of observational platforms provides 170,000 individual profiles, giving a broad spatial extent overlaid with areas of high spatial and temporal resolution. An internal tide signal is observed in all data, supporting previous studies indicating internal tides are ubiquitous throughout the ocean. Amplitudes were generally below 5 m along the Australian coastline, with larger amplitudes, up to 20 m, observed close to steep, critical topography. Detailed analysis of individual regions allows the mechanisms responsible for internal tide generation to be isolated, with these ranging from local generation over topography to remote generation on distant ridges. The final quality controlled estimate of the spatial structure represents a significant addition to the observational record of internal tides in the region.