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Technical Guides - Speed of Sound in Sea-Water

Revision History

This guide provides current information and equations for calculating the speed of sound in sea-water as a function of temperature, salinity and pressure (or depth).


Contents

  • Two simplified equations are those derived by Mackenzie and Coppens

  • UNESCO equation: Chen and Millero: The international standard algorithm, recalculated following the adoption of the International Temperature scale of 1990.

  • Del Grosso's equation: Preferred to the UNESCO equation by some researchers, also recalculated following the adoption of the International Temperature scale of 1990.


Also available:

  • Pressure or Depth: Converting from pressure to depth or from depth to pressure.

  • Uncertainties: Advice on the accuracy and precision of the various equations.

  • References: Up-to-date list of references on sound speed in sea-water.


For further information, contact Justin Ablitt