Coldest seawater

Last updated: March 28, 2020 at 4:13 am

Seawater with an average salinity of 35 ppt (parts per thousand) freezes at -1.94°C (28.5°F). The coldest seawater ever recorded at −2.6 °C (27.3 °F) was found in a stream under an Antarctic glacier.

“Sea ice covers about 7% of the Earth’s surface and about 12% of the world’s oceans. Much of the world’s sea ice is enclosed within the polar ice packs in the Earth’s polar regions: the Arctic ice pack of the Arctic Ocean and the Antarctic ice pack of the Southern Ocean.”¹

The record for the coldest salt water, which is not from a marine environment, is listed separately.
Sylte, Gudrun Urd (24 May 2010). Den aller kaldaste havstraumen.
¹ Sea ice. (2018, January 4). In Wikipedia, The Free Encyclopedia. Retrieved 17:29, January 5, 2018, from

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