The sound speed calculations made by the EK80 for salt water are based on the international standard algorithm, often known as the UNESCO algorithm. This algorithm uses
pressure rather than depth, and the EK80 thus provides a conversion from the depth value provided to pressure.
For more information about the algorithm, see the source documents:
|
1 |
C-T. Chen and F.J. Millero, Speed of sound in seawater at high pressures (1977) Journal of the Acoustic Society of America, Volume 62, Issue 5, pages 1129 to 1135 |
|
2 |
N.P. Fofonoff and R.C. Millard Jr. Algorithms for computation of fundamental properties of seawater (1983), UNESCO technical papers in marine science. No. 44, Division of Marine Sciences. UNESCO, Place de Fontenoy, 75700
Paris. |
|
3 |
G.S.K. Wong and S Zhu, Speed of sound in seawater as a function of salinity, temperature and pressure (1995) Journal of the Acoustic Society of America, Volume 97, Issue 3, pages 1732 to 1736 |
Some websites provide these algorithms online, and may also include interactive versions. One example is: