The Underwater World An Acoustician's Point of View

Guest speakers: Francine Desharnais

November 25, 1996 7:00 PM

Location: KC Irving Chemestry Centre, Room 128, University of Prince Edward Island

Francine Desharnais has worked at the Defense Research Establishment Atlantic (Dartmouth, Nova Scotia), and at the SACLANT Undersea Research Centre (NATO) in Italy. She is now a member of the Ocean Acoustics Group at DREA

The acoustic wave is a powerful tool to probe the underwater world. While light gets absorbed rather quickly in he ocean, sound can propagate over impressive distances. Sound can be used passively to listen to the diverse inhabitants fo the sea - from the small snapping shrimp adn the large marine mammals, to the ships and vessels crusing around the world seas. Or sound can interrogate the oceans actively to locate objects - the principal of sonar.

The November 1996 general meeting's focus was on ocean acoustics. Francine Desharnais delivered a talk on various aspects of undewater acoustics. She explained some of the differences between various types of sonar and discussed the phenomenon of sound channels. Ms. Desharnais explained how the Heard experiment, a study of the temperature of the oceans using acoustical techniques, had been shut down due to animal activism. She also touched on her work with acoustic transducers.