# calc_sound_speed

echopype.utils.uwa. calc_sound_speed temperature=27 salinity=35 pressure=10 formula_source='Mackenzie'

Calculate sound speed in [m/s].

Parameters

- temperature: num

  temperature [deg C]

- salinity: num

  salinity [PSU, part per thousand]

- pressure: num

  pressure [dbars]

- formula_source: str, {“Mackenzie”, “AZFP”}

  Source of formula used to calculate sound speed. “Mackenzie” (default) uses the formula from Mackenzie 1981 (see Notes below) as implemented in `arlpy` package. “AZFP” uses the formula supplied in the AZFP Matlab code.

Returns

- Sound speed [m/s] for each input temperature value.

Notes

Mackenzie KV (1981) Nine‐term equation for sound speed in the oceans. The Journal of the Acoustical Society of America, 70(3), 807–812. https://doi.org/10.1121/1.386920 The ranges of validity encompass the following: temperature −2 to 30 °C, salinity 30 to 40 ppt, and depth 0 to 8000 m.