Observing internal tides using ocean gliders
Observation of internal waves and internal tides using autonomous ocean gliders is problematic because gliders travel through the water at speeds similar to the waves themselves. Gliders are commonly used to repeatedly occupy short hydrographic sections, but this often results in aliasing with internal tides and so contaminating the dataset with unresolvable signals. I will discuss two recent glider missions over the European shelf slope, both designed to measure the internal tide by repeatedly diving around a single station (or series of stations). During the first mission, in the Faroe-Shetland Channel, the glider data was combined with data from a moored ADCP allowing direct calculation of internal tide energy fluxes. The second mission, in Whittard Canyon, was possibly the first use of a glider within a submarine canyon and measured internal tides as high as 160 m.