77-640: The Antarctic ( / æ n ˈ t ɑːr t ɪ k / or / æ n ˈ t ɑːr k t ɪ k / , American English also / æ n t ˈ ɑːr t ɪ k / or / æ n t ˈ ɑːr k t ɪ k / ; commonly / æ ˈ n ɑːr t ɪ k / ) is a polar region around Earth 's South Pole , opposite the Arctic region around the North Pole . The Antarctic comprises the continent of Antarctica , the Kerguelen Plateau , and other island territories located on
154-589: A few recent surveys, the non-arthropod invertebrate fauna of Heard Island remain poorly known. Beetles and flies dominate Heard Island's known insect fauna, which comprises up to 21 species of ectoparasite (associated with birds and seals) and up to 13 free-living species. Approximately half of the free-living insects are habitat-specific, while the remainder are generalists found in a variety of habitats, being associated with either supralittoral or intertidal zones, Poa cookii and Pringlea antiscorbutica stands, bryophytes , lichen-covered rocks, exposed rock faces or
231-580: A maximum elevation of 2,745 metres (9,006 ft) at Mawson Peak , the historically active volcanic summit of Big Ben, to which the average ascent from shore is steeper than that for any island of comparable size or larger; only seven smaller islands are steeper . A July 2000 satellite image from the University of Hawaii 's Institute of Geophysics and Planetology (HIGP) Thermal Alert Team showed an active 2-kilometre-long (1.2 mi) and 50- to 90-metre-wide (164–295 ft) lava flow trending south-west from
308-434: A number of algal species are recorded from there. At least 100 species of terrestrial algae are known from Heard Island, commonly in permanently moist and ephemeral habitats. Forests of the giant Antarctic kelp Durvillaea antarctica occur at a number of sites around Heard Island and at least 17 other species of seaweed are known, with more to be added following the identification of recent collections. Low seaweed diversity
385-498: A number of small wetland sites scattered around its coastal perimeter, including areas of wetland vegetation, lagoons or lagoon complexes, rocky shores and sandy shores, including the Elephant Spit . Many of these wetland areas are separated by active glaciers. There are also several short glacier-fed streams and glacial pools. Some wetland areas have been recorded on McDonald Island but, due to substantial volcanic activity since
462-467: A place called Oil Barrel Point. From 1855 to 1882 a number of American sealers spent a year or more on the island, living in appalling conditions in dark smelly huts, also at Oil Barrel Point. At its peak the community consisted of 200 people. By 1880, sealers had wiped out most of the seal population and then left the island. In all, the islands furnished more than 100,000 barrels of elephant seal oil during this period. A number of wrecks have occurred in
539-496: Is 1.13 square kilometres ( 7 ⁄ 16 sq mi). There is a small group of islets and rocks about 10 km ( 5 + 1 ⁄ 2 nmi) north of Heard Island, consisting of Shag Islet, Sail Rock, Morgan Island and Black Rock. They total about 1.1 square kilometres ( 7 ⁄ 16 sq mi) in area. Mawson Peak and McDonald Island are the only two active volcanoes in Australian territory. Mawson Peak
616-401: Is a complex ecosystem, especially along Antarctica's coastal zones. Coastal upwelling provides abundant nutrients that feed krill , a type of marine Crustacea , which in turn feed a complex of living creatures from penguins to blue whales . Heard Island and McDonald Islands The Territory of Heard Island and McDonald Islands ( HIMI ; ISO 3166 region code: HMD, HM, 334; )
693-541: Is also one of the highest Australian mountains (higher than Mount Kosciuszko ). It is surpassed by Dome Argus , Mount McClintock and Mount Menzies in the Australian Antarctic Territory , a territorial claim unrecognised by most other countries, meaning that Mawson Peak is the highest mountain over which Australia has true sovereignty . Mawson Peak has erupted several times in the last decade and as recently as May 2023. An earlier eruption
770-675: Is an Australian external territory comprising a volcanic group of mostly barren Antarctic islands, about two-thirds of the way from Madagascar to Antarctica . The group's overall land area is 372 km (144 sq mi) and it has 101.9 km (63 mi) of coastline. Discovered in the mid-19th century, the islands lie on the Kerguelen Plateau in the Indian Ocean and have been an Australian territory since 1947. Heard Island and McDonald Islands contain Australia's only two active volcanoes . The summit of one, Mawson Peak ,
847-519: Is best developed on coastal areas at elevations below 250 m. Bryophytes (mosses and liverworts) contribute substantially to the overall biodiversity of Heard Island, with 43 mosses and 19 liverworts being recorded, often occupying habitats unsuitable for vascular plants, such as cliff faces. Bryophytes are present in most of the major vegetation communities including several soil and moss-inhabiting species. A 1980 survey of McDonald Island found lower diversity than that on Heard Island; four mosses and
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#1732757376646924-597: Is commonly accepted to have occurred in 1820 by the Russian expedition of Fabian Gottlieb von Bellingshausen and Mikhail Lazarev on Vostok and Mirny . The Australian James Kerguelen Robinson (1859–1914) was the first human born in the Antarctic, on board the sealing ship Offley in the Gulf of Morbihan (Royal Sound then), Kerguelen Island on 11 March 1859. The first human born and raised on an Antarctic island
1001-546: Is credited to the Spaniard Gabriel de Castilla , who reported seeing distant southern snow-capped mountains in 1603. The first Antarctic land discovered was the island of South Georgia , visited by the English merchant Anthony de la Roché in 1675. Although such myths and speculation about a Terra Australis ("Southern Land") date back to antiquity, the first confirmed sighting of the continent of Antarctica
1078-434: Is due to the island's isolation from other land masses, unsuitable beach habitat, constant abrasion by waves, tides and small stones, and the extension of glaciers into the sea in many areas. Heard Island has a range of terrestrial environments in which vegetation occurs. Seven general vegetation communities are currently recognised, although vegetation composition is considered more of a continuum than discrete units: One of
1155-536: Is high. This is due to the combination of low species diversity and climatic amelioration. During the 2003/04 summer a new plant species, Cotula plumosa , was recorded. Only one small specimen was found growing on a coastal river terrace that had experienced substantial development and expansion of vegetation over the past decade. The species has a circumantarctic distribution and occurs on many subantarctic islands. 71 species of lichens have been recorded from Heard Island and they are common on exposed rock, dominating
1232-800: Is higher than any mountain in all other Australian states, territories or claimed territories , except Dome Argus , Mount McClintock and Mount Menzies in the Australian Antarctic Territory . This Antarctic territory is a land claim unrecognised by most other countries, meaning that Mawson Peak is the highest mountain over which Australia has true sovereignty . The islands are among the most remote places on Earth : They are located about 4,100 kilometres (2,200 nautical miles) southwest of Perth , 3,850 km (2,080 nmi) southwest of Cape Leeuwin , Australia, 4,200 km (2,300 nmi) southeast of South Africa , 3,830 km (2,070 nmi) southeast of Madagascar , 1,630 km (880 nmi) north of Antarctica, and 450 km (240 nmi) southeast of
1309-608: Is in the order of 1,300 to 1,900 mm (51.2 to 74.8 in); rain or snow falls on about 3 out of 4 days. According to the Australian Bureau of Meteorology , Heard Island (Atlas Cove) receives an average of 96.8 snowy days annually. Meteorological records at Heard Island are incomplete. The islands are part of the Southern Indian Ocean Islands tundra ecoregion that includes several subantarctic islands. In this cold climate, plant life
1386-523: Is mainly limited to grasses, lichens, and mosses . Low plant diversity reflects the islands' isolation, small size, severe climate, the short, cool growing season and, for Heard Island, substantial permanent ice cover. The main environmental determinants of vegetation on subantarctic islands are wind exposure, water availability, parent soil composition, salt spray exposure, nutrient availability, disturbance by trampling (from seabirds and seals) and, possibly, altitude. At Heard Island, exposure to salt spray and
1463-842: Is sufficient precipitation to form permanent ice , short and still cold summers, and extreme variations in daylight hours, with twenty-four hours of daylight in summer, and complete darkness at mid-winter . There are many settlements in Earth's north polar region. Countries with claims to Arctic regions are: the United States ( Alaska ), Canada ( Yukon , the Northwest Territories and Nunavut ), Denmark ( Greenland ), Norway , Finland , Sweden , Iceland , and Russia . Arctic circumpolar populations, though small, often share more in common with each other than with other populations within their national boundaries. As such,
1540-604: Is the surface area of the Antarctica continent itself. All of the land and ice shelves south of 60°S latitude are administered under the Antarctic Treaty System . Biogeographically , the Antarctic realm is one of eight biogeographic realms on Earth's land surface. Climate change in Antarctica is particularly important because the melting of the Antarctic ice sheet has a high potential to add to
1617-594: The Antarctic Convergence now absent from the Heard Island flora may colonise the island if climate change produces more favourable conditions. Some plant species are spreading and modifying the structure and composition of communities, some of which are also increasing in distribution. It is likely that further changes will occur, and possibly at an accelerated rate. Changes in population numbers of seal and seabird species are also expected to affect
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#17327573766461694-624: The Antarctic Plate or south of the Antarctic Convergence . The Antarctic region includes the ice shelves , waters, and all the island territories in the Southern Ocean situated south of the Antarctic Convergence , a zone approximately 32 to 48 km (20 to 30 mi) wide and varying in latitude seasonally. The region covers some 20 percent of the Southern Hemisphere , of which 5.5 percent (14 million km)
1771-600: The Antarctic fur seal and the subantarctic fur seal . Leopard seals visit regularly in winter to haul-out though they do not breed on the islands. Crabeater , Ross and Weddell seals are occasional visitors. Heard Island and the McDonald Islands are free from introduced predators and provide crucial breeding habitat in the middle of the vast Southern Ocean for a range of birds. The surrounding waters are important feeding areas for birds and some scavenging species also derive sustenance from their cohabitants on
1848-485: The Heard shag . Although not a true seabird, the Heard Island subspecies of the black-faced sheathbill also breeds on the island. Both the shag and the sheathbill are endemic to Heard Island. A further 28 seabird species are recorded as either non-breeding visitors or have been noted during 'at-sea surveys' of the islands. All recorded breeding species, other than the Heard Island sheathbill, are listed marine species under
1925-508: The Kerguelen Islands (part of French Southern and Antarctic Lands ). The islands, which are uninhabited, can be reached only by sea, which from Australia takes two weeks in the vessels normally used to access them. Neither island cluster had recorded visitors until the mid-1850s. An American sailor, John Heard, on the ship Oriental , sighted Heard Island on 25 November 1853, en route from Boston to Melbourne . He reported
2002-728: The Patanela expedition). The second ascent was made by five members of the Heard Island Expedition 1983 (sometimes referred to as the Anaconda expedition). A helicopter landing was made at the summit by an ANARE team on 21 December 1986. An Australian Army team was successful in making the third ascent in 2000. In 1991, the islands were the location for the Heard Island feasibility test , an experiment in very long-distance transmission of low frequency sound through
2079-745: The archipelagos of the Balleny Islands , Peter I Island , Scott Island , the South Orkney Islands , and the South Shetland Islands . However, this area does not include the Antarctic Convergence , a transition zone where the cold waters of the Southern Ocean collide with the warmer waters of the north, forming a natural border to the region. Because the Convergence changes seasonally, the Convention for
2156-527: The frigid zones or polar zones , of Earth are Earth's polar ice caps , the regions of the planet that surround its geographical poles (the North and South Poles ), lying within the polar circles . These high latitudes are dominated by floating sea ice covering much of the Arctic Ocean in the north, and by the Antarctic ice sheet on the continent of Antarctica and the Southern Ocean in
2233-609: The Antarctic Convergence area, while the Isla Grande de Tierra del Fuego , Falkland Islands , Isla de los Estados , Hornos Island with Cape Horn , Diego Ramírez Islands , Campbell Island , Macquarie Island , Amsterdam and Saint Paul Islands, Crozet Islands , Prince Edward Islands , Gough Island , and Tristan da Cunha group remain north of the Convergence and thus outside the Antarctic region. A variety of animals live in Antarctica for at least some of
2310-655: The Australian Environmental Protection and Biodiversity Act (1999, four are listed as threatened species and five are listed migratory species. Under the EPBC Act a recovery plan has been made for albatrosses and giant petrels, which calls for ongoing population monitoring of the species found at HIMI, and at the time of preparing this plan a draft recovery plan has also been made for the Heard Island cormorant (or shag) and Antarctic tern. The recorded populations of some seabird species found in
2387-619: The Conservation of Antarctic Marine Living Resources approximates the Convergence line by joining specified points along parallels of latitude and meridians of longitude . The implementation of the convention is managed through an international commission headquartered in Hobart , Australia, by an efficient system of annual fishing quotas, licenses, and international inspectors on the fishing vessels, as well as satellite surveillance. The islands situated between 60°S latitude parallel to
Antarctic - Misplaced Pages Continue
2464-457: The Earth's atmosphere in which it may be absorbed, scattered or reflected, which is the same thing that causes winters to be colder than the rest of the year except in tropical regions. The axial tilt of the Earth has the most effect on climate of the polar regions due to its latitude. However, since the polar regions are the farthest from the equator , they receive the weakest solar radiation and are therefore generally frigid year round due to
2541-558: The Ramsar Convention. Non-wetland vegetated parts of the islands also support penguin and other seabird colonies. The islands have an Antarctic climate, or Tundra climate ( ET ) under the Köppen climate classification, tempered by their maritime setting. The weather is marked by low seasonal and daily temperature ranges; persistent and generally low cloud cover; frequent precipitation and strong winds. Snowfall occurs throughout
2618-497: The Reserve have shown marked change. The king penguin population is the best studied seabird species on Heard Island and has shown a dramatic increase since first recorded in 1947/48, with the population doubling every five years or so for more than 50 years. A paper reviewing population data for the black-browed albatross between 1947 and 2000/01 suggested that the breeding population had increased to about three times that present in
2695-728: The South Georgia and the South Sandwich Islands Marine Protection Area created in 2012. The latter exceeds the surface area of another vast protected territory, the Greenland National Park 's 972,000 km (375,000 sq mi). (While the Ross Sea Marine Protection Area established in 2016 is still larger at 1.55 million km, its protection is set to expire in 35 years.) To protect
2772-556: The West Antarctic, the ocean has warmed by 1 °C (1.8 °F) since 1955. The fresh, 1100-1500 billion tons (GT) per year of meltwater from the ice dilutes the saline Antarctic bottom water , weakening the lower cell of the Southern Ocean overturning circulation (SOOC). According to some research, a full collapse of the SOOC may occur a between 1.7 °C (3.1 °F) and 3 °C (5.4 °F) of global warming, although
2849-675: The area, all Antarctic ships over 500 tonnes are subject to mandatory regulations under the Polar Code , adopted by the International Maritime Organization (in force since 1 January 2017). Climate change caused by greenhouse gas emissions from human activities occurs everywhere on Earth, and while Antarctica is less vulnerable to it than any other continent, climate change in Antarctica has been observed. Since 1959, there has been an average temperature increase of >0.05 °C/decade since 1957 across
2926-679: The callsigns VK0HI (the Anaconda expedition) and VK0JS and VK0NL (the Cheynes II expedition), with a further operation in January 1997 (VK0IR). The DXpedition in March 2016 (VK0EK) was organised by Cordell Expeditions, and made over 75,000 radio contacts. Mawson Peak, atop Big Ben, was first climbed on 25 January 1965 by five members of the Southern Indian Ocean Expedition to Heard Island (sometimes referred to as
3003-418: The coast. Relics that survive from that time include trypots, casks, hut ruins, graves and inscriptions. This caused the seal populations there to either become locally extinct or reduced to levels too low to exploit economically. Modern sealers visited from Cape Town in the 1920s. Since then the populations have generally increased and are protected. Seals breeding on Heard include the southern elephant seal ,
3080-727: The conference were presented at the Antarctic Treaty states' meeting in Uruguay in May 2010. Because Antarctica surrounds the South Pole , it is theoretically located in all time zones . For practical purposes, time zones are usually based on territorial claims or the time zone of a station's owner country or supply base. 90°00′S 00°00′W / 90.000°S -0.000°E / -90.000; -0.000 Polar regions of Earth The polar regions , also called
3157-489: The continent, although it had been uneven. West Antarctica warmed by over 0.1 °C/decade from the 1950s to the 2000s, and the exposed Antarctic Peninsula has warmed by 3 °C (5.4 °F) since the mid-20th century. The colder, stabler East Antarctica had been experiencing cooling until the 2000s. Around Antarctica, the Southern Ocean has absorbed more oceanic heat than any other ocean, and has seen strong warming at depths below 2,000 m (6,600 ft). Around
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3234-583: The discovery one month later and had the island named after him. His wife Fidelia Heard provided the first written description and drawings of the island. William McDonald aboard the Samarang discovered the nearby McDonald Islands six weeks later, on 4 January 1854. No landing took place on the islands until March 1855, when sealers from the Corinthian , led by Erasmus Darwin Rogers , went ashore at
3311-461: The early 1950s and the late 1980s. Heard Island supports a relatively low number of terrestrial invertebrate species compared to other Southern Ocean islands, in parallel with the low species richness in the flora–that is, the island's isolation and limited ice-free area. Endemism is also generally low and the invertebrate fauna is exceptionally pristine with few, if any, (successful) human-induced introductions of alien species. Two species, including
3388-543: The earth's axial tilt of 23.5° not being enough to create a high maximum midday declination to sufficiently compensate the Sun's rays for the high latitude even in summer, except for relatively brief periods in peripheral areas near the polar circles. The large amount of ice and snow also reflects and weakens of what weak sunlight the polar regions receive further, contributing to the cold. Polar regions are characterized by extremely cold temperatures, heavy glaciation wherever there
3465-749: The full effects are expected to occur over multiple centuries; these include less precipitation in the Southern Hemisphere but more in the Northern Hemisphere , an eventual decline of fisheries in the Southern Ocean and a potential collapse of certain marine ecosystems . While many Antarctic species remain undiscovered, there are documented increases in Antarctic flora , and large fauna such as penguins are already having difficulty retaining suitable habitat. On ice-free land, permafrost thaws release greenhouse gases and formerly frozen pollution. The first recorded sighting of Antarctica
3542-407: The global sea level rise . Further, this melting also disrupts the flow of Southern Ocean overturning circulation , which would have significant effects on the local climate and marine ecosystem functioning.There is no permanent country in Antarctica . As defined by the Antarctic Treaty System , the Antarctic region is everything south of the 60°S latitude . The Treaty area covers Antarctica and
3619-451: The harsh climate was a major contributor towards species richness, but multiple correlations have been found with area, temperature, remoteness of islands, and food chain stability. For example, herbivorous insects are poor in number due to low plant richness, and likewise, indigenous bird numbers are related to insects, which are a major food source. The Antarctic hosts the world's largest protected area comprising 1.07 million km,
3696-433: The islands. The islands have been identified by BirdLife International as an Important Bird Area because they support very large numbers of nesting seabirds. Nineteen species of birds have been recorded as breeding on Heard Island and the McDonald Islands, although recent volcanic activity at the McDonald Islands in the last decade is likely to have reduced vegetated and un-vegetated nesting areas. Penguins are by far
3773-782: The last landing was made in 1980, their present extent is unknown. The HIMI wetland is listed on the Directory of Important Wetlands in Australia and, in a recent analysis of Commonwealth-managed wetlands, was ranked highest for nomination under the Convention on Wetlands of International Importance Especially as Waterfowl Habitat (Ramsar Convention) as an internationally important wetland. Six wetland types have been identified from HIMI covering approximately 1860 ha: coastal 'pool complex' (237 ha); inland 'pool complex' (105 ha); vegetated seeps mostly on recent glaciated areas (18 ha); glacial lagoons (1103 ha); non-glacial lagoons (97ha); Elephant Spit (300 ha) plus some coastal areas. On Heard Island,
3850-500: The late 1940s, although a Convention for the Conservation of Antarctic Marine Living Resources CCAMLR) Working Group was cautious about the interpretation of the increasing trend given the disparate nature of the data, as discussed in the paper. The discovery of a large, previously unknown, colony of Heard shags in 2000/01 at Cape Pillar raised the known breeding population from 200 pairs to over 1000 pairs. The breeding population of southern giant petrels decreased by more than 50% between
3927-482: The major vegetation components. The vascular flora comprises the smallest number of species of any major subantarctic island group, reflecting its isolation, small ice-free area and severe climate. Twelve vascular species are known from Heard Island, of which five have also been recorded on McDonald Island. None of the vascular species are endemic, although Pringlea antiscorbutica , Colobanthus kerguelensis , and Poa kerguelensis occur only on subantarctic islands in
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#17327573766464004-458: The majority of these types suites are found below 150 m asl. The wetland vegetation occurs in the 'wet mixed herbfield' and 'coastal biotic vegetation' communities described above. The wetlands provide important breeding and feeding habitat for a number of Antarctic and subantarctic wetland animals. These include the southern elephant seal and macaroni , gentoo , king and eastern rockhopper penguins, considered to be wetland species under
4081-712: The most abundant birds on the islands, with four breeding species present, comprising king , gentoo , macaroni and eastern rockhopper penguins . The penguins mostly colonise the coastal tussock and grasslands of Heard Island, and have previously been recorded as occupying the flats and gullies on McDonald Island. Other seabirds recorded as breeding at Heard Island include three species of albatross ( wandering , black-browed and light-mantled albatrosses ), southern giant petrels , Cape petrels , four species of burrowing petrels ( Antarctic and Fulmar prions , common and South Georgia diving petrels ), Wilson's storm petrels , kelp gulls , subantarctic skuas , Antarctic terns and
4158-607: The most popular destinations being the Antarctic Peninsula area (especially the South Shetland Islands ) and South Georgia Island . In December 2009, the growth of tourism , with consequences for both the ecology and the safety of the travellers in its great and remote wilderness, was noted at a conference in New Zealand by experts from signatories to the Antarctic Treaty . The definitive results of
4235-459: The most rapidly changing physical settings in the subantarctic has been produced on Heard Island by a combination of rapid glacial recession and climate warming. The consequent increase in habitat available for plant colonisation, plus the coalescing of previously discrete ice-free areas, has led to marked changes in the vegetation of Heard Island in the last 20 years or so. Other species and vegetation communities found on subantarctic islands north of
4312-631: The northern polar region is diverse in human settlements and cultures. The southern polar region has no permanent human habitation as of now. McMurdo Station is the largest research station in Antarctica , run by the United States. Other notable stations include Palmer Station and Amundsen–Scott South Pole Station (United States), Esperanza Base and Marambio Base ( Argentina ), Scott Base ( New Zealand ), and Vostok Station (Russia). While there are no indigenous human cultures, there
4389-524: The ocean. The US Navy chartered vessels MV Cory Chouest and Amy Chouest were used to transmit signals which could be detected as far away as both ocean coasts of the US and Canada. Heard Island, by far the largest of the group, is a 368-square-kilometre (142 sq mi) mountainous island covered by 41 glaciers (the island is 80% covered with ice ) and dominated by the Big Ben massif . It has
4466-527: The original areas and have expanded beyond them. Expeditioner boot traffic during the Australian Antarctic program expedition in 1987 may be at least partly responsible for the spread, but it is probably mainly due to dispersal by wind and the movement of seabirds and seals around the island. The potential for introducing plant species (including invasive species not previously found on subantarctic islands) by both natural and human-induced means
4543-409: The other two climatic and biometric belts of Earth, a tropics belt near the equator, and two middle latitude regions located between the tropics and polar regions . Polar regions receive less intense solar radiation than the other parts of Earth because the Sun's energy arrives at an oblique angle , spreading over a larger area, being less concentrated, and also travels a longer distance through
4620-459: The presence of breeding and moulting seabirds and seals is a particularly strong influence on vegetation composition and structure in coastal areas. Evidence from microfossil records indicates that ferns and woody plants were present on Heard Island during the Tertiary (a period with a cool and moist climate). Neither group of plants is present today, although potential Tertiary survivors include
4697-497: The south and the Antarctic Convergence to the north and their respective 200-nautical-mile (370 km) exclusive economic zones fall under the national jurisdiction of the countries that possess them: South Georgia and the South Sandwich Islands (United Kingdom), Bouvet Island (Norway), and Heard and McDonald Islands (Australia). Kerguelen Islands (France; also an EU Overseas territory) are situated in
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#17327573766464774-583: The south. The Arctic has various definitions, including the region north of the Arctic Circle (currently Epoch 2010 at 66°33'44" N), or just the region north of 60° north latitude, or the region from the North Pole south to the timberline . The Antarctic is usually defined simply as south of 60° south latitude, or the continent of Antarctica. The 1959 Antarctic Treaty uses the former definition. The two polar regions are distinguished from
4851-484: The southern Indian Ocean. The plants are typically subantarctic, but with a higher abundance of the cushion-forming Azorella selago than other subantarctic islands. Heard Island is the largest subantarctic island with no confirmed human-introduced plants. Areas available for plant colonisation on Heard Island are generally the result of retreating glaciers or new ice-free land created by lava flows. Today, substantial vegetation covers over 20 km of Heard Island, and
4928-467: The southernmost. In late 1977, Silvia Morella de Palma, who was then seven months pregnant, was airlifted to Esperanza Base , in order to complete her pregnancy in the base. The airlift was a part of the Argentine solutions to the sovereignty dispute over territory in Antarctica. Emilio was automatically granted Argentine citizenship by the government since his parents were both Argentine citizens, and he
5005-414: The summit of Big Ben. The much smaller and rocky McDonald Islands are located 44 kilometres (27 mi) to the west of Heard Island. They consist of McDonald Island (186 m or 610 ft high), Flat Island (55 m or 180 ft high) and Meyer Rock (170 m or 560 ft high). They total approximately 2.5 square kilometres ( 15 ⁄ 16 sq mi) in area, where McDonald Island
5082-693: The thrips Apterothrips apteris and the mite Tyrophagus putrescentiae are thought to be recent, possibly natural, introductions. An exotic species of earthworm Dendrodrilus rubidus was also collected in 1929 from a dump near Atlas Cove, and has recently been collected from a variety of habitats including wallows, streams and lakes on Heard Island. The arthropods of Heard Island are comparatively well known with 54 species of mite and tick , one spider and eight springtails recorded. A study over summer at Atlas Cove in 1987/88 showed overall densities of up to 60 000 individual springtails per square metre in soil under stands of Pringlea antiscorbutica . Despite
5159-435: The underside of rocks. There is a pronounced seasonality to the insect fauna, with densities in winter months dropping to a small percentage (between 0.75%) of the summer maximum. Distinct differences in relative abundances of species between habitats has also been shown, including a negative relationship between altitude and body size for Heard Island weevils. The fauna of the freshwater pools, lakes, streams and mires found in
5236-491: The vascular plant Pringlea antiscorbutica and six moss species. Volcanic activity has altered the distribution and abundance of the vegetation. The vascular flora covers a range of environments and, although only six species are currently widespread, glacial retreat and the consequent connection of previously separate ice-free areas is providing opportunities for further distribution of vegetation into adjacent areas. Low-growing herbaceous flowering plants and bryophytes are
5313-659: The vegetation by changing nutrient availability and disturbance through trampling. One plant species on Heard Island, Poa annua , a cosmopolitan grass native to Europe, was possibly introduced by humans, though is more likely to have arrived naturally, probably by skuas from the Kerguelen Islands where it is widespread. It was initially recorded in 1987 in two deglaciated areas of Heard Island not previously exposed to human visitors, while being absent from known sites of past human habitation. Since 1987 Poa annua populations have increased in density and abundance within
5390-454: The vegetation in some areas. As with plants, a 1980 survey of McDonald Island found lower diversity there, with just eight lichen species and a number of non-lichenized fungi recorded. The main indigenous animals are insects along with large populations of ocean-going seabirds , seals and penguins . Sealing at Heard Island lasted from 1855 to 1910, during which time 67 sealing vessels are recorded visiting, nine of which were wrecked off
5467-500: The vicinity of the islands. There is also a discarded building left from John Heard's sealing station that is situated near Atlas Cove. The islands were formally claimed by the United Kingdom in 1910 and transferred to Australia on 26 December 1947. The transfer was confirmed in letters exchanged on 19 December 1950. The archipelago became a World Heritage Site in 1997. The first recorded aircraft landing on McDonald Island
5544-410: The year, including: Most of the Antarctica continent is permanently covered by ice and snow, leaving less than 1 percent of the land exposed. There are only two species of flowering plant, Antarctic hair grass and Antarctic pearlwort , but a range of mosses , liverworts , lichens and macrofungi . Biodiversity among terrestrial flora and fauna is low on the islands: studies have theorized that
5621-585: The year. Monthly average temperatures at Atlas Cove (at the northwestern end of Heard Island) range from 0.0 to 4.2 °C (32.0 to 39.6 °F), with an average daily range of 3.7 to 5.2 °C (38.7 to 41.4 °F) in summer and −0.8 to 0.3 °C (30.6 to 32.5 °F) in winter. The winds are predominantly westerly and persistently strong. At Atlas Cove, monthly average wind speeds range between around 26 and 33.5 km/h (16.2 and 20.8 mph). Gusts in excess of 180 km/h (110 mph) have been recorded. Annual precipitation at sea level on Heard Island
5698-659: Was Solveig Gunbjørg Jacobsen born on 8 October 1913 in Grytviken , South Georgia. Emilio Marcos Palma (born 7 January 1978) is an Argentine man who was the first documented person born on the continent of Antarctica at the Esperanza Base . His father, Captain Jorge Palma, was head of the Argentine Army detachment at the base. While ten people have been born in Antarctica since, Palma's birthplace remains
5775-448: Was born in the claimed Argentine Antarctica . Palma can be considered to be the first native Antarctican. The Antarctic region had no indigenous population when first discovered, and its present inhabitants comprise a few thousand transient scientific and other personnel working on tours of duty at the several dozen research stations maintained by various countries. However, the region is visited by more than 40,000 tourists annually,
5852-474: Was filmed on 2 February 2016. The volcano on McDonald Island, after being dormant for 75,000 years, became active in 1992 and has erupted several times since, the most recently in 2005. Heard Island and the McDonald Islands have no ports or harbours; ships must anchor offshore. The coastline is 101.9 km (63.3 mi) in extent, and a 12 nmi (22 km) territorial sea and 200 nmi (370 km) exclusive fishing zone are claimed. Heard Island has
5929-426: Was made by Australian scientists Grahame Budd and Hugh Thelander on 12 February 1971, using a helicopter. There were at least five private expeditions to Heard Island between 1965 and 2000. Several amateur radio operators have visited Heard, often associated with scientific expeditions. The first activity there was in 1947 by Alan Campbell-Drury. Two amateur radio DXpeditions to the island took place in 1983 using
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