calculation in Seawater
use the calculator below, enter the values of
water temperature , salinity and
depth . When a
calculation button is pushed, the
values for the sound speed in seawater are displayed on a screen. The
four alternatives are derived using algorithms from the sources
(1)The Equation of Mackenzie Mackenzie, K.V. "Nine-term Equation
for Sound Speed in the Oceans", J. Acoust. Soc. Am. 70 (1981), 807-812.
(2)The Equation of Coppens A.B. Coppens, Simple equations for the
speed of sound in Neptunian waters (1981) J. Acoust. Soc. Am. 69(3), pp
(3)The Equation of Del Grosso
"A New Equation for the speed of sound in Natural Waters", J. Acoust.
Soc. Am. 56#4 (1974).
Equation of UNESCO (Chen and Millero) Chen and Millero, "The Sound Speed in Seawater", J. Acoust. Soc. Am. 62 (1977),
The UNESCO equation is true for
the oceanographers' standard ocean, defined as an ideal medium with a
temperature of 0 degrees Celsius and salinity of 35 parts per thousand.
Parthiot (1998) give a table of corrections which are needed when
the standard formula is applied to specific oceans and seas. The
equation and interactive version do not apply any corrections.
calculation of the speed of sound
profile of the depth direction.
A CSV file for STD is necessary for the
sample files are prepared.
When T,S,D value is input into the
following columns, sound speed in
seawater by each equation is calculated.
north and the south latitude are not distinguished. When you do not have a
value, input 45.
per thousand )
Please describe reference site (http://www.tsuchiya2.org/) when you
use the result of the calculation by this site.