ภาวะเค็ม

thumb|upright=1.3|right|Annual mean sea surface salinity for the World Ocean. Data from the [[World Ocean Atlas 2009.]] thumb|upright|right|International Association for the Physical Sciences of the Oceans (IAPSO) standard seawater. Salinity () is the saltiness or amount of salt dissolved in a body of water, called saline water (see also soil salinity). It is usually measured in g/L or g/kg (grams of salt per liter/kilogram of water; the latter is dimensionless and equal to ‰).