The Weddell Sea is part of the Southern Ocean and contains the Weddell Gyre. Its land boundaries are defined by the bay formed from the coasts of Coats Land and the Antarctic Peninsula. The easternmost point is Cape Norvegia at Princess Martha Coast, Queen Maud Land. To the east of Cape Norvegia is the King Haakon VII Sea. Much of the southern part of the sea, up to Elephant Island, is permanent ice, the Filchner-Ronne Ice Shelf. The sea is contained within the two overlapping Antarctic territorial claims of Argentina, (Argentine Antarctica) and Britain (British Antarctic Territory), and also resides partially within the territorial claim of Chile (Antarctic Chilean Territory). At its widest the sea is around 2,000 km across, in area it is around 2.8 million km².
In his 1950 book The White Continent, historian Thomas R. Henry writes:
|The Weddell Sea is, according to the testimony of all who have sailed through its berg-filled waters, the most treacherous and dismal region on earth. The Ross Sea is the relatively peaceful, predictable, and safe.|
He continues for an entire chapter, relating myths of the green-haired merman sighted in the sea's icy waters, the inability of crews to navigate a path to the coast until 1949, and treacherous "flash freezes" that left ships, such as Ernest Shackleton's Endurance, at the mercy of the ice floes.
The sea is named after the Scottish sailor James Weddell, who entered the sea in 1823 and originally named it after King George IV; it was renamed in Weddell's honour in 1900. Also in 1823, the American sealing captain Benjamin Morrell claimed to have seen land some 10–12° east of the sea's actual eastern boundary. He called this New South Greenland, but its existence was disproved when the sea was more fully explored in the early 20th century. Weddell got as far south as 74°S; the furthest southern penetration since Weddell but before the modern era was made by the Scot William Speirs Bruce in 1903.
Various ice shelves, including the Filchner-Ronne Ice Shelf, fringe the Weddell sea. Some of the ice shelves on the east side of the Antarctic Peninsula, which used to extend roughly 3900 square miles (10,000 km²) over the Weddell Sea, had completely disappeared by 2002; see Retreat of glaciers since 1850#Antarctica. Whilst a dramatic event, the area that disappeared was far smaller than the total area of ice shelf that remains.
Characteristic fauna of the sea include the Weddell Seal.
The Weddell Sea has been deemed by scientists to have the clearest water of any sea. Dutch researchers from the German Alfred Wegener Institute, on finding a Secchi disc visible at a depth of 262 feet on October 13, 1986, ascertained that the clarity corresponded to that of distilled water.
The Weddell Sea is an important area of deep water mass formation through cabbeling, the main driving force of the thermohaline circulation. Deep water masses are also formed through cabbeling in the North Atlantic and are caused by differences in temperature and salinity of the water. In the Weddell sea this is brought about mainly by brine exclusion and wind cooling.
- Henry, Thomas R. (1950), The White Continent: The Story of Antarctica, New York Sloane
- Smith, Michael (2004), Sir James Wordie, Polar Crusader: Exploring the Arctic and Antarctic, Birlinn, ISBN 978-1-84158-292-4 – via Questia (subscription required)
- Foraminifera of the Weddell Sea bottom, an image gallery of hundreds of specimens of deep-sea Foraminifera from depths around 4400m.