Weddell Sea
Weddell Sea | |
---|---|
Location | Southern Ocean |
Coordinates | 73°S 45°W / 73°S 45°W |
Type | Sea |
Basin countries | Argentine Antarctica, British Antarctic Territory, partially within the Antarctic Chilean Territory. |
Surface area | 2,800,000 km2 (1,081,100 sq mi) |
Average depth | 500 m (1,640 ft) |
Max. depth | 5,148 m (16,890 ft) |
Frozen | partially |
The Weddell Sea is part of the
The sea is contained within the two overlapping Antarctic territorial claims of Argentine Antarctica, the British Antarctic Territory, and also resides partially within the Antarctic Chilean Territory. At its widest the sea is around 2,000 kilometres (1,200 mi) across, and its area is around 2.8 million square kilometres (1.1×10 6 sq mi).[1]
Various ice shelves, including the Filchner-Ronne Ice Shelf, fringe the Weddell sea. Some of the ice shelves on the east side of the
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 relatively peaceful, predictable, and safe."[4] 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.
Etymology
The sea is named after the Scottish sailor
The Weddell Sea is an important area of deep water mass formation through
History
In 1823, British sailor James Weddell discovered the Weddell Sea.
The Antarctic Sound is named after the expedition ship of Otto Nordenskiöld. The sound that separates the tip of the Antarctic Peninsula from Dundee Island is also referred to as "Iceberg Alley", because of the huge icebergs that are often seen here. Snowhill Island, located east of the Antarctic Peninsula is almost completely snow-capped, hence its name. The Swedish Antarctic Expedition under Otto Nordenskiöld built a cabin on the island in 1902, where Nordenskiöld and three members of the expedition had to spend two winters.
In 1915, Ernest Shackleton's ship, Endurance, got trapped and was crushed by ice in this sea. After 15 months on the pack-ice Shackleton and his men managed to reach Elephant Island and safely returned home.[6] In March 2022, it was announced that the well-preserved wreck of the Endurance had been discovered four miles (6.4 km) from its anticipated location, at a depth of 3,008 metres (9,869 ft).[7]
Geology
As with other neighboring parts of Antarctica, the Weddell Sea shares a common geological history with southernmost
Oceanography
The Weddell Sea is one of few locations in the
Circulation in the western Weddell Sea is dominated by a northward flowing current. This northward current is the western section of a primarily wind-driven, cyclonic gyre called the Weddell Gyre. This northward flow serves as the primary force of departure of water from the Weddell Sea, a major site of ocean water modification and deep water formation, to the remainder of the World Ocean. The Weddell Gyre is a cold, low salinity surface layer separated by a thin, weak pycnocline from a thick layer of relatively warm and salty water referred to as Weddell Deep Water (WDW), and a cold bottom layer.[12]
Circulation in the Weddell Sea has proven difficult to quantify. Geopotential surface heights above the 1000 dB level, computed using historical data, show only very weak surface currents. Similar computations carried out using more closely spaced data also showed small currents. Closure of the gyre circulation was assumed to be driven by
Thus, in addition to a wind-driven gyre component of the boundary current, a deeper circulation whose dynamics and transports reflect an input of dense water in the southern and southwestern Weddell Sea are expected. Available data does not lend to the quantification of the volume transports associated with this western boundary region, or to the determination of deep convective circulation along the western boundary.[12]
Climate
The predominance of strong surface winds parallel to the narrow and tall mountain range of the Antarctic Peninsula is a remarkable feature of weather and climate in the area of the western Weddell Sea. The winds carry cold air toward lower latitudes and turn into southwesterlies farther north.
These winds are of interest not only because of their effect on the temperature regime east of the peninsula but also because they force the drift of ice northeastward into the South Atlantic Ocean as the last branch of the clockwise circulation in the lower layers of the atmosphere along the coasts of the Weddell Sea. The sharp contrast between the wind, temperature, and ice conditions of the two sides of the Antarctic Peninsula has been well known for many years.[13]
Strong surface winds directed equatorward along the east side of the Antarctic Peninsula can appear in two different types of synoptic-meteorological situations: an intense cyclone over the central Weddell Sea, a broad east to west flow of stable cold air in the lowest 500-to-1000-metre layer of the atmosphere over the central and/or southern Weddell Sea toward the peninsula. These conditions lead to cold air piling up on the east edge of the mountains. This process leads to the formation of a high-pressure ridge over the peninsula (mainly east of the peak) and, therefore, a deflection of the originally westward current of air to the right, along the mountain wall.[13]
Ecology
The Weddell Sea is abundant with whales and seals. Characteristic fauna of the sea include the
The Adélie penguin is the dominant penguin species in this remote area because of their adaptation to the harsh environment. A colony of more than 100,000 pairs of Adélies can be found on volcanic Paulet Island.
Around 1997, the northernmost emperor penguin colony was discovered just south of Snowhill Island in the Weddell Sea. As the Weddell Sea is often clogged with heavy pack-ice, strong ice-class vessels equipped with helicopters are required to reach this colony.[6]
In 2021,
In February 2021 the Alfred Wegener Institute for Polar and Marine Research with RV Polarstern, a colony of approximately 60 million Jonah's icefish was found to inhabit an area in the Weddell Sea. It is estimated that the colony covers around 240 square kilometers, with an average of one nest per every three square meters.[15][16]
Seabed features
References
Notes
- ^ "Weddell Sea". Encyclopædia Britannica.
- ^ Retreat of glaciers since 1850 § Antarctica
- .
- ^ Henry 1950.
- ^ Smith 2004, p. 38.
- ^ a b "Weddell Sea – Highlights". Oceanwide Expeditions.
- ^ "Endurance is Found" (Press release). Endurance22.org. Retrieved 14 March 2022.
- ^ .
- ^ ISBN 9783319230603.
- S2CID 221779070.
- ^ Beckmann, Hellmer & Timmermann 1999.
- ^ a b Muench, Gordon & 1995.
- ^ a b Schwerdtfeger 1979.
- ISSN 2296-7745.
- ^ Katie Hunt (13 January 2022). "A colony of 60 million fish with transparent blood has been discovered in Antarctica". CNN. Retrieved 2022-01-13.
- PMID 35030328.
Bibliography
- Beckmann, A.; et al. (1999). "A numerical model of the Weddell Sea: Large-scale circulation and water mass distrib Polarstern Knollution". J. Geophys. Res. 104 (C10): 23375–23391. .
- Henry, T. R. (1950), The White Continent: The Story of Antarctica, New York: Sloane, OCLC 487172
- Muench, R. D.; et al. (1995). "Circulation and transport of water along the western Weddell Sea margin" (PDF). J. Geophys. Res. 100 (C9): 18503–18515. .
- Smith, M. (2004), Sir James Wordie, Polar Crusader: Exploring the Arctic and Antarctic, Birlinn, ISBN 9781841582924
- Schwerdtfeger, W. (1979). "Meteorological aspects of the drift of ice from the Weddell Sea toward the mid-latitude westerlies". J. Geophys. Res. 84 (C10): 6321–6328. .
External links
- Media related to Weddell Sea at Wikimedia Commons
- Foraminifera of the Weddell Sea bottom, an image gallery of hundreds of specimens of deep-sea Foraminifera from depths around 4,400 metres