Salinity measurements are valuable to marine oceanographers as they are one of the best proxies for ‘finger-printing’ a water mass. Salinity provides valuable insights as to whether the world’s oceans are becoming fresher or saltier as the climate changes. Monitoring salinity is also important to aquaculture industries as salinity levels can indicate how fresh marine waters have become after rain events.

Salinity measurements are performed on a Guildline 8400 Autosal. This instrument measures conductivity, which is then converted to salinity in units of Practical Salinity Units (PSU). All instruments are calibrated yearly by CSIRO’s Calibration Lab and are calibrated by the analyst prior to each analytical run.

Concentration range; 0.005 – 42.0 Practical Salinity Unit (PSU).

Measurement uncertainty; 0.001 PSU.

An OSIL certified reference material for conductivity is run with every analytical run.


The ‘Salinity Room’. This small room within the Hydrochemistry laboraory is temperature controlled (constant 24 degrees C) for the most stable and accurate analysis possible.