Dissolved oxygen (DO) measurements in saline (sea)water

Most DO probes already compensate for temperature, but still need to correct the readings for salinity. To correct for salinity both the salinity as well as the temperature have to be measured at the same time as performing a DO measurement.
The YDOC data loggers are provided with up to 8 calculation channels, which can a/o be used to correct DO readings.
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The equation to compensate DO readings for salinity is as follows:
DO_C = :DO * exp(-1*:SAL*(0.017674+(-10.754+2140.7/:TEMPK)/:TEMPK)))
Where :DO is the measured dissolved oxygen in mg/l, :SAL is the salinity in g/kg brine and :TEMPK the water temperature in Kelvin. - The equation to express DO as a percent of saturation is:
DO% = (:DO_C/:DOSAT)*100
Where :DO_C is the compensated DO reading in mg/l and :DOSAT the dissolved oxygen saturation value in mg/l at the measured temperature and salinity. - The equation to calculate DO saturation in mg/l is:
DOSAT = exp(-139.34411+(1.575701E5+(-6.642308E7+(1.2438E10-8.621949E11/:TEMPK)/:TEMPK)/:TEMPK)/:TEMPK)*exp(-1*:SAL*(0.017674+(-10.754+2140.7/:TEMPK)/:TEMPK)))
Where :SAL is the measured salinity in g/kg brine and :TEMPK the water temperature in Kelvin.