The handling of salinity was one of the novelties in TEOS-10. It defines the relationship between Reference Salinity and Practical Salinity, Chlorinity or Absolute Salinity and accounts for the different chemical compositions by adding a regionally variable 𝛿 S A (see Figure). TEOS-10 is valid for Vienna Standard Mean Ocean Water which accounts for different hydrogen- and oxygen-isotope compositions in water which affects the triple point and therefore phase transitions of water.