[178] The hole was detected by scientists in 1985[179] and has tended to increase over the years of observation. A study by Eric Steig published in 2009 noted for the first time that the continent-wide average surface temperature trend of Antarctica is slightly positive at >0.05 °C (0.09 °F) per decade from 1957 to 2006. Sand and silts were laid down in what is now the Ellsworth, Horlick and Pensacola Mountains. However, there is some evidence of antarctic marine glaciation during the Cretaceous period.[65]. NOTE: 1) The information regarding Antarctica on this page is re-published from the 2020 World Fact Book of the United States Central Intelligence Agency and other sources. East Antarctica is geologically varied, dating from the Precambrian era, with some rocks formed more than 3 billion years ago. [64] It was during this era that Gondwana began to break up. Large animals such as some cetaceans and birds make the round trip annually. [109][110], Several countries claim sovereignty in certain regions. Scientists from the USA make up the largest single group, but citizens of 19 other countries were also resident on the world's most southerly continent in 2008. Geologists tend to study plate tectonics, meteorites from outer space, and resources from the breakup of the supercontinent Gondwana. The name Antarctica is the romanised version of the Greek compound word ἀνταρκτική (antarktiké), feminine of ἀνταρκτικός (antarktikós),[9] meaning "opposite to the Arctic", "opposite to the north". The areas shown as Australia's and New Zealand's claims were British territory until they were handed over following the countries' independence. For more: 0808 120 2333, quarkexpeditions.com Meet the people who call Antarctica home The introduction of alien plants or animals can bring a criminal penalty, as can the extraction of any indigenous species. [118] In 1988, the Convention on the Regulation of Antarctic Mineral Resources (CRAMRA) was adopted. [119] The following year, however, Australia and France announced that they would not ratify the convention, rendering it dead for all intents and purposes. Emilio Marcos Palma was the first person born south of the 60th parallel south, which is the continental limit. Australia currently claims the largest area. [160][161][162] However, increased ice outflow has been suggested in some regions. Temperatures reach a minimum of between −80 °C (−112 °F) and −89.2 °C (−128.6 °F) in the interior in winter and reach a maximum of between 5 °C (41 °F) and 15 °C (59 °F) near the coast in summer. Mount Erebus and Mount Terror are named after two ships from his expedition: HMS Erebus and Terror. [103], About 300 million years ago Permian forests started to cover the continent, and tundra vegetation survived as late as 15 million years ago,[104] but the climate of present-day Antarctica does not allow extensive vegetation to form. Minor eruptions are frequent, and lava flow has been observed in recent years. [173][174] According to NASA, the most widespread Antarctic surface melting of the past 30 years occurred in 2005, when an area of ice comparable in size to California briefly melted and refroze; this may have resulted from temperatures rising to as high as 5 °C (41 °F). [156], A single 2015 study by H. Jay Zwally et al. This ice is formed from the ocean water and floats in the same water and thus does not contribute to rise in sea level. Around 23 Ma, the Drake Passage opened between Antarctica and South America, resulting in the Antarctic Circumpolar Current that completely isolated the continent. Glaciologists in Antarctica are concerned with the study of the history and dynamics of floating ice, seasonal snow, glaciers, and ice sheets. [68] The ice began to spread, replacing the forests that until then had covered the continent. According to various organisations (the National Science Foundation,[23] NASA,[24] the University of California, San Diego,[25] the Russian State Museum of the Arctic and Antarctic,[26] among others),[27][28] ships captained by three men sighted Antarctica or its ice shelf in 1820: Fabian Gottlieb von Bellingshausen (a captain in the Imperial Russian Navy), Edward Bransfield (a captain in the Royal Navy), and Nathaniel Palmer (a sealer from Stonington, Connecticut). Hawaii is politically part of North America, but geographically it is not part of any continent. [7] The temperature in Antarctica has reached −89.2 °C (−128.6 °F) (or even −94.7 °C (−135.8 °F) as measured from space[8]), though the average for the third quarter (the coldest part of the year) is −63 °C (−81 °F). As a result, the diversity of plant life is very low and limited in distribution. The orbital distance contributes to a colder Antarctic winter (and a warmer Antarctic summer) but the first two effects have more impact. While a few of these countries have mutually recognised each other's claims,[111] the validity of these claims is not recognised universally.[1]. As you might imagine, Antarctica has a very small population.Around The most common rocks in West Antarctica are andesite and rhyolite volcanics formed during the Jurassic period. Charles Wilkes, and a separate French expedition under Jules Dumont d'Urville. On 18 December 2012, the British Foreign and Commonwealth Office named a previously unnamed area Queen Elizabeth Land in tribute to Queen Elizabeth II's Diamond Jubilee. The Argentine, British and Chilean claims all overlap, and have caused friction. [126], Other countries participating as members of the Antarctic Treaty have a territorial interest in Antarctica, but the provisions of the Treaty do not allow them to make their claims while it is in force. [citation needed] Several Antarctic ice streams, which account for about 10% of the ice sheet, flow to one of the many Antarctic ice shelves: see ice-sheet dynamics. Because of this, and the presence of scientists from other countries around the world, Antarctica has a very cosmopolitan population. During clear days in summer, more solar radiation reaches the surface at the South Pole than at the equator because of the 24 hours of sunlight each day at the Pole. If life is discovered in Lake Vostok, it would strengthen the argument for the possibility of life on Europa. Those features can also be observed in algae and cyanobacteria, suggesting that these are adaptations to the conditions prevailing in Antarctica. In West Antarctica, coniferous forests dominated through the entire Cretaceous period (146–66 Ma), though southern beech became more prominent towards the end of this period. With the ban of CFCs in the Montreal Protocol of 1989, climate projections indicate that the ozone layer will return to 1980 levels between 2050 and 2070. None. [85], Emilio Marcos Palma was the first person born south of the 60th parallel south, the first born on the Antarctic mainland, and the only living human to be the first born on any continent. Glaciation began at the end of the Devonian period (360 Ma), as Gondwana became centred on the South Pole and the climate cooled, though flora remained. [105] Growth is restricted to a few weeks in the summer. Concerns have been raised that disruption of ice shelves may result in increased glacial outflow from the continental ice mass.[153]. This means that it is a very cold continent where water is mostly in the form of ice. [93] Invertebrate life includes microscopic mites like the Alaskozetes antarcticus, lice, nematodes, tardigrades, rotifers, krill and springtails. [72] However, new techniques such as remote sensing, ground-penetrating radar and satellite imagery have begun to reveal the structures beneath the ice. With 14 million square kilometers (5.4 million square miles) of area, it's the 5th largest continent. All attempted crossings, with no kites or resupplies, that have tried to go from the true continental edges, where the ice meets the sea, have failed due to the great distance that needs to be covered. In the 7 continent model in fact, it is not always clear where to place Russia. [69] It was first recorded near the Beardmore Glacier by Frank Wild on the Nimrod Expedition, and now low-grade coal is known across many parts of the Transantarctic Mountains. Military personnel or equipment are permitted only for scientific research or other peaceful purposes. [95] The snow petrel is one of only three birds that breed exclusively in Antarctica. Africa separated from Antarctica in the Jurassic, around 160 Ma, followed by the Indian subcontinent in the early Cretaceous (about 125 Ma). The wildlife of Antarctica are extremophiles, having to adapt to the dryness, low temperatures, and high exposure common in Antarctica.The extreme weather of the interior contrasts to the relatively mild conditions on the Antarctic Peninsula and the subantarctic islands, which have warmer temperatures and more liquid water.Much of the ocean around the mainland is covered by sea ice. Due to its location at the South Pole, Antarctica receives relatively little solar radiation except along the southern summer.
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