Salinity

![Annual mean sea surface salinity for the World Ocean. Data from the World Ocean Atlas 2009.[1]](/uploads/202501/21/WOA09_sea-surf_SAL_AYool2405.png)


Salinity is the saltiness or dissolved salt content of a body of water (see also soil salinity). Salinity is an important factor in determining many aspects of the chemistry of natural waters and of biological processes within it, and is a thermodynamic state variable that, along with temperature and pressure, governs physical characteristics like the density and heat capacity of the water.