This function calculates salinity from measurements of conductivity, temperature, and sea pressure, using the TEOS-10 GSW function
gsw_SP_from_C. The result is added to the
data field in the RSK structure, and the channel metadata records are updated (
units in channels). It requires an RSK structure that contains conductivity, temperature, and pressure data as well as the TEOS-10 toolbox.
If there is already a salinity channel present, the function replaces the values with a new calculation of salinity.
If sea pressure is not present, this function calculates it with the default atmospheric pressure, usually 10.1325 dbar. We suggest using
RSKderiveseapressure before this function for a customizable atmospheric pressure.