Internal tide impact measured by acoustic tomography experiment

Abstract

The INTIMATE (internal tide impact measured by acoustic tomography experiment) project is devoted to the study of internal tides by use of acoustic tomography schemes. The first exploratory experiment was carried out in June 1996 on the continental shelf off the coast of Portugal using a towed broadband acoustic source (500–800 Hz) and a four-hydrophone vertical array. Acoustic data were collected for 5 days, including legs where the source ship was moving and legs with the ship on station. Intensive environmental surveys (XBT, CDT, bottom and hull-mounted ADCP, thermistor chain, bathymetry, geoacoustic characteristics of the sediments) were also conducted. The purpose of the presentation is to give the preliminary results of acoustic data processing and to evaluate the impact of internal tides on the acoustic propagation in a shallow water environment. Future works will deal with inversions in terms of sound speed and geoacoustic parameter estimation. [Work supported by SHOM-IH-UAL. The hydrophones array was provided by the SACLANT Undersea Research Center, La Spezia, Italy.]