The Thermosalinograph or TSG is an measuring instrument mounted near the water intake of ships to continuously measure sea surface temperature and conductivity while the ship is in motion.
[1] Various programs have been developed to assist in the collection and analysis of data from a TSG.
The data can be used to calculate salinity, density, sound velocity within the water, and other parameters.
NOAA fleet Ship of Opportunity Program (SOOP) Global Ocean Observing System (GOOS) GOSUD Global Ocean Surface Underway Data (http://www.gosud.org) The thermosalinograph uses a conductivity cell to measure conductivity, which can then be translated into a value of salinity.
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