Time-lapse Acoustic Imaging of Oceanic Fronts and Eddies

Seismic reflection surveying is used to generate acoustic images of the water column where acoustic impedance contrasts are produced by variations in temperature and, to some extent, salinity. In this way, two- and three-dimensional images of thermohaline circulation can be generated. Critically, these images have equal vertical and horizontal resolutions of order 10 m. Here, I present results from a two-dimensional seismic survey from the Bellingshausen Sea of the Southern Ocean and a three-dimensional seismic survey from the Brazil-Falkland Confluence located offshore Uruguay. These observations reveal a sub-mesoscale warm-core eddy field and deep-reaching front. The analysis of these data have significant implications for ice shelf melting and frontal dynamics.