Seawatter or saut watter is watter frae a sea or ocean. On average, seawatter in the warld's oceans haes a salinity o aboot 3.5% (35 g/L, or 599 mM). This means that ivery kilogram (aboot ane litre bi vollum) o seawatter has approximately 35 gram (1.2 oz) o dissolved sauts (predominantly sodium (Na+
) an chloride (Cl−
) ions). Average density at the surface is 1.025 g/ml. Seawatter is denser nor baith fresh watter an shire watter (density 1.0 g/ml @ 4 °C (39 °F)) acause the dissolved sauts add mass withoot contributing significantly tae the vollum. The freezing pynt o seawatter decreases as saut concentration increases. At teepical salinity it freezes at aboot −2 °C (28 °F). The cauldest seawatter iver recordit (in a liquid state) wis in 2010, in a stream unner an Antarctic glacier, an meisured −2.6 °C (27.3 °F).
- "U.S. Office of Naval Research Ocean, Water: Temperature". Archived frae the original on 12 December 2007. Retrieved 6 December 2013.
- Sylte, Gudrun Urd (24 Mey 2010). "Den aller kaldaste havstraumen". forskning.no (in Norse). Archived frae the original on 6 Mairch 2012. Retrieved 24 Mey 2010.