Rapid Underwater Ocean Measurements Using Brillouin Scattering

A method is proposed to measure the speed of sound in the sea as a function of depth using a laser. A pulsed laser beam will be projected into the sea and the Brillouin scattered returning radiation will be analysed. The depths will be determined by the time delay between the outgoing and return light, and the speed of sound by the wavelength spread between the components of the Brillouin scattered light. These measurements can be made with great rapidity and accuracy.