Wilkins Sound is a
seaway in
Antarctica
Antarctica () is Earth's southernmost and least-populated continent. Situated almost entirely south of the Antarctic Circle and surrounded by the Southern Ocean, it contains the geographic South Pole. Antarctica is the fifth-largest contine ...
that is largely occupied by the Wilkins Ice Shelf. It is located on the southwest side of the
Antarctic Peninsula
The Antarctic Peninsula, known as O'Higgins Land in Chile and Tierra de San Martín in Argentina, and originally as Graham Land in the United Kingdom and the Palmer Peninsula in the United States, is the northernmost part of mainland Antarctic ...
between the concave western coastline of
Alexander Island
Alexander Island, which is also known as Alexander I Island, Alexander I Land, Alexander Land, Alexander I Archipelago, and Zemlja Alexandra I, is the largest island of Antarctica. It lies in the Bellingshausen Sea west of Palmer Land, Antarc ...
and the shores of
Charcot Island
Charcot Island or Charcot Land is an island administered under the Antarctic Treaty System, long and wide, which is ice covered except for prominent mountains overlooking the north coast. Charcot Island lies within the Bellingshausen Sea, wes ...
and
Latady Island farther to the west.
Its northern portion was first seen and roughly mapped in 1910 by the
French Antarctic Expedition
The French Antarctic Expedition is any of several French expeditions in Antarctica.
First expedition
In 1772, Yves-Joseph de Kerguelen-Trémarec and the naturalist Jean Guillaume Bruguière sailed to the Antarctic region in search of the fable ...
under
Jean-Baptiste Charcot
Jean-Baptiste-Étienne-Auguste Charcot (15 July 1867 – 16 September 1936), born in Neuilly-sur-Seine, was a French scientist, medical doctor and polar scientist. His father was the neurologist Jean-Martin Charcot (1825–1893).
Life
Jean-Ba ...
and was observed from the air in 1929 by Sir
Hubert Wilkins
Sir George Hubert Wilkins MC & Bar (31 October 188830 November 1958), commonly referred to as Captain Wilkins, was an Australian polar explorer, ornithologist, pilot, soldier, geographer and photographer. He was awarded the Military Cross afte ...
. The configuration of the sound was determined in 1940 on exploratory flights by the
US Antarctic Service
The United States Antarctic Program (or USAP; formerly known as the United States Antarctic Research Program or USARP and the United States Antarctic Service or USAS) is an organization of the United States government which has presence in the A ...
(USAS). It was named by the USAS for Sir
Hubert Wilkins
Sir George Hubert Wilkins MC & Bar (31 October 188830 November 1958), commonly referred to as Captain Wilkins, was an Australian polar explorer, ornithologist, pilot, soldier, geographer and photographer. He was awarded the Military Cross afte ...
, who in 1929 first proved "Charcot Land" to be an island (see
Charcot Island
Charcot Island or Charcot Land is an island administered under the Antarctic Treaty System, long and wide, which is ice covered except for prominent mountains overlooking the north coast. Charcot Island lies within the Bellingshausen Sea, wes ...
) and thereby indirectly discovered this feature. The existence of Latady Island at the southwest side of the sound was determined in 1960 by D.J.H. Searle of
Falkland Islands Dependencies Survey
The British Antarctic Survey (BAS) is the United Kingdom's national polar research institute. It has a dual purpose, to conduct polar science, enabling better understanding of global issues, and to provide an active presence in the Antarctic on ...
(FIDS) by examination of air photos taken by the
Ronne Antarctic Research Expedition
The Ronne Antarctic Research Expedition (RARE) was an expedition from 1947–1948 which researched the area surrounding the head of the Weddell Sea in Antarctica.
Background
Finn Ronne led the RARE which was the final privately sponsored exp ...
(RARE), 1947–48.
On 5 April 2009 the thin bridge of ice to the Wilkins Ice Shelf off the coast of Antarctica splintered, and scientists expect it could cause the collapse of the Shelf. There are reports the shelf has exploded into hundreds of small
iceberg
An iceberg is a piece of freshwater ice more than 15 m long that has broken off a glacier or an ice shelf and is floating freely in open (salt) water. Smaller chunks of floating glacially-derived ice are called "growlers" or "bergy bits". The ...
s.
David Vaughan of the
British Antarctic Survey
The British Antarctic Survey (BAS) is the United Kingdom's national polar research institute. It has a dual purpose, to conduct polar science, enabling better understanding of global issues, and to provide an active presence in the Antarctic on ...
has attributed these events to
global warming
In common usage, climate change describes global warming—the ongoing increase in global average temperature—and its effects on Earth's climate system. Climate change in a broader sense also includes previous long-term changes to E ...
.
Wilkins Ice Shelf
The Wilkins Ice Shelf is a rectangular
ice shelf
An ice shelf is a large floating platform of ice that forms where a glacier or ice sheet flows down to a coastline and onto the ocean surface. Ice shelves are only found in Antarctica, Greenland, Northern Canada, and the Russian Arctic. The b ...
about long and wide (). This feature occupies the central part of Wilkins Sound, from which it takes its name. The name was proposed by the
UK Antarctic Place-Names Committee
The UK Antarctic Place-Names Committee (or UK-APC) is a United Kingdom government committee, part of the Foreign and Commonwealth Office, responsible for recommending names of geographical locations within the British Antarctic Territory (BAT) and ...
(UK-APC) in 1971.
Breakup and collapse events
In 1993, Professor David Vaughan of the
British Antarctic Survey
The British Antarctic Survey (BAS) is the United Kingdom's national polar research institute. It has a dual purpose, to conduct polar science, enabling better understanding of global issues, and to provide an active presence in the Antarctic on ...
(BAS) predicted that the northern part of the Wilkins ice shelf was likely to be lost within 30 years if climate warming on the Peninsula were to continue at the same rate.
A study by the
National Academy of Sciences
The National Academy of Sciences (NAS) is a United States nonprofit, non-governmental organization. NAS is part of the National Academies of Sciences, Engineering, and Medicine, along with the National Academy of Engineering (NAE) and the Nati ...
in 2002 stated, "Because air temperatures are statistically increasing along the
Antarctic Peninsula
The Antarctic Peninsula, known as O'Higgins Land in Chile and Tierra de San Martín in Argentina, and originally as Graham Land in the United Kingdom and the Palmer Peninsula in the United States, is the northernmost part of mainland Antarctic ...
region, the presence of glacial
meltwater
Meltwater is water released by the melting of snow or ice, including glacial ice, tabular icebergs and ice shelves over oceans. Meltwater is often found in the ablation zone of glaciers, where the rate of snow cover is reducing. Meltwater can be ...
is likely to become more prevalent in these surface waters and continue to play an ever-increasing role in driving this fragile ecosystem." In 2008 David Vaughan conceded his predictions had been too conservative and that events on the ground were moving quicker than he anticipated.
On 25 March 2008 a chunk of the Wilkins ice shelf disintegrated, putting an even larger portion of the glacial ice shelf at risk.
[Associated Press, "Western Antarctic Ice Chunk Collapses"](_blank)
/ref> Scientists were surprised when they discovered the rest of the ice shelf is beginning to break away from the continent. What is left of the Wilkins ice shelf is now connected by only a narrow beam of ice. At the end of May 2008, another break-off further reduced the width of the connecting ice strip from . This second smaller event, with about of ice separating, was the first documented break-up that occurred in winter.
The Wilkins Ice Shelf is not connected to inland glaciers in the same way as the Larsen B Ice Shelf
The Larsen Ice Shelf is a long ice shelf in the northwest part of the Weddell Sea, extending along the east coast of the Antarctic Peninsula from Cape Longing to Smith Peninsula. It is named after Captain Carl Anton Larsen, the master of the N ...
was and will therefore have a negligible effect on sea level rise
Globally, sea levels are rising due to human-caused climate change. Between 1901 and 2018, the globally averaged sea level rose by , or 1–2 mm per year on average.IPCC, 2019Summary for Policymakers InIPCC Special Report on the Ocean and Cry ...
.
On 29 November 2008, the European Space Agency
, owners =
, headquarters = Paris, Île-de-France, France
, coordinates =
, spaceport = Guiana Space Centre
, seal = File:ESA emblem seal.png
, seal_size = 130px
, image = Views in the Main Control Room (1205 ...
(ESA) announced that the Wilkins Ice Shelf has lost around so far in 2008. A satellite image captured 26 November 2008 shows new rifts on the ice shelf that make it dangerously close to breaking away from the strip of ice—and the islands to which it is connected, the ESA said.
On 20 January 2009, Reuters
Reuters ( ) is a news agency owned by Thomson Reuters Corporation. It employs around 2,500 journalists and 600 photojournalists in about 200 locations worldwide. Reuters is one of the largest news agencies in the world.
The agency was estab ...
reported that the ice shelf could collapse into the ocean within "weeks or months". The shelf was then only held up by a very thin strip of ice (varying from 2 km to 500 meters at the narrowest), which made it very vulnerable to cracks and fissures. If the strip were to break, it would release the ice shelf, which now has the area of the state of Connecticut
Connecticut () is the southernmost state in the New England region of the Northeastern United States. It is bordered by Rhode Island to the east, Massachusetts to the north, New York to the west, and Long Island Sound to the south. Its cap ...
(about 14,000 km²). Satellite evidence from 2 April 2009 led ESA analysts to conclude that the collapse of the strip (which would result in a partial break-away from the Antarctic Peninsula) was "imminent". Pursuant to this determination, ESA's Envisat
Envisat ("Environmental Satellite") is a large inactive Earth-observing satellite which is still in orbit and now considered space debris. Operated by the European Space Agency (ESA), it was the world's largest civilian Earth observation satell ...
satellite is observing the area on a daily basis. The satellite acquisitions are updated automatically to monitor the developments immediately as they occur. Additionally NASA
The National Aeronautics and Space Administration (NASA ) is an independent agency of the US federal government responsible for the civil space program, aeronautics research, and space research.
NASA was established in 1958, succeeding t ...
's Terra
Terra may often refer to:
* Terra (mythology), primeval Roman goddess
* An alternate name for planet Earth, as well as the Latin name for the planet
Terra may also refer to: Geography Astronomy
* Terra (satellite), a multi-national NASA scienti ...
and Aqua
Aqua is the Latin word for water. It is used in many words which relate to water, such as aquatic life. In English, it may also refer to:
Arts
* Aqua (color), a greenish-blue color
Business
* Aqua (skyscraper), an 82-story residential skysc ...
satellites overfly the area several times a day and some of the images acquired are also available.
On 5 April 2009, the ice bridge
An ice bridge is a frozen natural structure formed over seas, bays, rivers or lake surfaces. They facilitate migration of animals or people over a water body that was previously uncrossable by terrestrial animals, including humans. The most sig ...
connecting part of the ice shelf to Charcot Island
Charcot Island or Charcot Land is an island administered under the Antarctic Treaty System, long and wide, which is ice covered except for prominent mountains overlooking the north coast. Charcot Island lies within the Bellingshausen Sea, wes ...
collapsed. The break occurred at the thinnest point in the bridge and was the first in any of the sections that connect it to the mainland. While only a section has broken away, some scientists predicted that another large section of the Wilkins Ice Shelf was only days away from completely breaking off. The shelf remains connected to Latady Island, although it has been stated that this connection "looks set to collapse" as well. The breakaway is seen as firm evidence of the ongoing effects of warming. Temperatures in this region of Antarctica have risen by 2.5 degrees Celsius since the 1950s.[ Some scientists believe that the collapse of the weakened ice was triggered by increased wave action due to the current relative absence of sea ice, however, a prominent glaciologist, Doug MacAyeal, has said the trigger for the original break-up in March 2008 was likely the much longer wavelengths of ocean swells created by distant storms.
If the entire shelf, which is approximately the size of ]Jamaica
Jamaica (; ) is an island country situated in the Caribbean Sea. Spanning in area, it is the third-largest island of the Greater Antilles and the Caribbean (after Cuba and Hispaniola). Jamaica lies about south of Cuba, and west of His ...
(10,991 km2, 4,244 sq mi),[ does completely break away from land it would be the largest one to do so, thus far.][ In the month of April 2009 alone, approximately 700 square kilometers (about 270.3 square miles) has broken off Wilkins Sound since the collapse of the ice bridge.
The disintegration of the fringe of the ice shelf, weakened by previous breakups, has continued in March 2013.]
Image:Wilkins Ice Bridge Collapse (1).jpg, The Wilkins ice bridge still intact.
Image:Wilkins Ice Bridge Collapse (2).jpg, The ice bridge is gone, replaced by chunks of ice.
See also
*Bellingshausen Sea
The Bellingshausen Sea is an area along the west side of the Antarctic Peninsula between 57°18'W and 102°20'W, west of Alexander Island, east of Cape Flying Fish on Thurston Island, and south of Peter I Island (there the southern ''Vostokkyste ...
*George VI Sound
George VI Sound or Canal Jorge VI or Canal Presidente Sarmiento or Canal Seaver or King George VI Sound or King George the Sixth Sound is a major bay/ fault depression, 300 miles (483 km) long and mainly covered by a permanent ice shelf. It ...
*Larsen Ice Shelf
The Larsen Ice Shelf is a long ice shelf in the northwest part of the Weddell Sea, extending along the east coast of the Antarctic Peninsula from Cape Longing to Smith Peninsula. It is named after Captain Carl Anton Larsen, the master of the No ...
*List of Antarctic ice shelves
This is a list of Antarctic ice shelves.
Ice shelves are attached to a large portion of the Antarctic coastline. Their total area is 1,541,700 km2. Names are also listed in the Scientific Committee on Antarctic Research, Gazetteer. The ...
*Rothschild Island
Rothschild Island is a black rugged island long, mainly ice-covered but surmounted by prominent peaks of Desko Mountains in Antarctica, west of the north part of Alexander Island in the north entrance to Wilkins Sound.
History
The island was ...
Notes
{{coord, 70, 15, S, 73, 00, W, type:waterbody_scale:2000000, display=title
Sounds of Antarctica
Bodies of water of Alexander Island