Antarctic Peninsula
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The Antarctic Peninsula () is the northernmost part of the mainland of Antarctica, and almost the only part of that continent that extends outside the Antarctic Circle. It lies in the Western Hemisphere, facing South America. It extends from a line between Cape Adams (Weddell Sea) and a point on the mainland south of Eklund Islands, to Prime Head (63º13'S).
The first sighting of Antarctic Peninsula is contested but it apparently occurred in the 1820s. Agreement on this name by the US-ACAN and UK-APC in 1964 resolved a long-standing difference over the use of the American name "Palmer Peninsula" or the British name "Graham Land" for this feature. Graham Land is now that part of the Antarctic Peninsula northward of a line between Cape Jeremy and Cape Agassiz, whilst Palmer Land is the part southward of that line. In Chile, it is officially referred as O'Higgins Land, after the Chilean patriot and Antarctic visionary. The other Spanish countries call it "Península Antártica", among them is Argentina (though also calls it "Tierra de San Martín"), which has more bases and personnel there than any other nation.
The peninsula is highly mountainous, its highest peaks rising to approximately 2,800 metres (9,186 feet). These mountains are considered to be a continuation of the Andes of South America, with a submarine spine connecting the two. That is an argument used by Chile and Argentina for their territorial claims. The peninsula has a sharp elevation gradient, with glaciers flowing into the Larsen Ice Shelf, which experienced significant breakup in 2002.
Since the peninsula has the mildest climate in Antarctica, the highest concentration of research stations on the continent can be found there, or on the many nearby islands.
Hope Bay, at , is near to the northernmost extremity of the peninsula, which is Prime Head, at 63º13'S.
See also
- Argentine Antarctica
- Magallanes y la Antártica Chilena Region
- British Antarctic Territory
- Antarctic Treaty System
Study Shows Antarctic Glaciers Shrinking Thu Apr 21, 2005, By EMMA ROSS, AP Medical Writer, LONDON The first comprehensive survey of glaciers on the Antarctic peninsula has shown that the rivers of ice are shrinking, mostly because of warming of the local climate. It is unclear, however, whether the increased temperature causing the shrinkage is a natural regional effect or a result of human-influenced global warming, said the scientists who conducted the study, published this week in the journal Science. Researchers from the British Antarctic Survey and the U.S. Geological Survey analyzed more than 2,000 aerial photographs dating from 1940 and over 100 satellite images from the 1960s onwards. They calculated that 87 percent of the 244 glaciers going out to sea from the peninsula have retreated over the last 50 years and that the pace of shrinkage has accelerated over the last decade. Until now, scientists were uncertain whether the glaciers were growing or melting. "Fifty years ago, most of the glaciers we look at were slowly growing in length but since then this pattern has reversed. In the last five years the majority were actually shrinking rapidly," said the study's leader, Alison Cook of the British Antarctic Survey. "However, 32 glaciers go against the trend and are showing minor advance. Had we not studied such a large number of glaciers we may have missed the overall pattern." The Antarctic peninsula is a small segment of the Antarctic continent, located at the South Pole, and the behavior of the ice on the peninsula is not necessarily a reflection of what's going on elsewhere in Antarctica, said another of the investigators, David Vaughan of the British Antarctic Survey. Temperatures seem to be much warmer there than on the rest of the continent. Evidence from the main Antarctic ice sheet is mixed, with some areas of the continent showing shrinkage and others showing thickening. Ice shrinkage has also been documented in Alaska and the North Pole. Scientists worry about the melting of the ice sheets because the extra water may increase sea levels, which in turn could mean more flooding damage to coastal areas during storms. Sea levels have risen by 10 centimeters to 20 centimeters over the last 100 years and experts predict it could rise by a meter over the next 100 years. However, the study was not able to tell whether the shrinkage is having a meaningful impact on sea levels. It is also unclear whether changes in the larger ice sheet in Antarctica are contributing to sea level rise, Vaughan said. "This is another piece in the jigsaw that tells us how climate change is affecting the planet. It may not be a significant piece, but there's a million-piece jigsaw out there to be filled in ... and this is one piece in it," Vaughan said.
External links
- ["Of Ice and Men"] Account of a tourist visit to the Antarctic Peninsula by Roderick Eime
- [Biodiversity at Ardley Island, South Shetland archipelago, Antarctic Peninsula]
- [89 photos of the Antarctic Peninsula]
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