42-463: The Nordenskiöld Base is a name used for the facilities shared by the Antarctic stations Wasa (Sweden) and Aboa (Finland). The name is in honors Otto Nordenskjöld , a Finnish-Swedish polar explorer who led the first Swedish Antarctic Expedition . 73°03′S 13°20′W / 73.050°S 13.333°W / -73.050; -13.333 This Princess Astrid Coast location article
84-495: A map, the circles of latitude may or may not be parallel, and their spacing may vary, depending on which projection is used to map the surface of the Earth onto a plane. On an equirectangular projection , centered on the equator, the circles of latitude are horizontal, parallel, and equally spaced. On other cylindrical and pseudocylindrical projections, the circles of latitude are horizontal and parallel, but may be spaced unevenly to give
126-542: Is a stub . You can help Misplaced Pages by expanding it . Antarctic 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
168-485: Is an abstract east – west small circle connecting all locations around Earth (ignoring elevation ) at a given latitude coordinate line . Circles of latitude are often called parallels because they are parallel to each other; that is, planes that contain any of these circles never intersect each other. A location's position along a circle of latitude is given by its longitude . Circles of latitude are unlike circles of longitude, which are all great circles with
210-585: 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
252-533: 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
294-505: Is drawn as a "line on a map", which was made in massive scale during the 1884 Berlin Conference , regarding huge parts of the African continent. North American nations and states have also mostly been created by straight lines, which are often parts of circles of latitudes. For instance, the northern border of Colorado is at 41° N while the southern border is at 37° N . Roughly half
336-516: Is equal to the Earth's axial tilt. By definition, the positions of the Tropic of Cancer , Tropic of Capricorn , Arctic Circle and Antarctic Circle all depend on the tilt of the Earth's axis relative to the plane of its orbit around the Sun (the "obliquity of the ecliptic"). If the Earth were "upright" (its axis at right angles to the orbital plane) there would be no Arctic, Antarctic, or Tropical circles: at
378-513: Is the longest circle of latitude and is the only circle of latitude which also is a great circle. As such, it is perpendicular to all meridians. There are 89 integral (whole degree ) circles of latitude between the Equator and the poles in each hemisphere , but these can be divided into more precise measurements of latitude, and are often represented as a decimal degree (e.g. 34.637° N) or with minutes and seconds (e.g. 22°14'26" S). On
420-704: The 60°S latitude . The Treaty area covers Antarctica and 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
462-589: The Mercator projection or on the Gall-Peters projection , a circle of latitude is perpendicular to all meridians . On the ellipsoid or on spherical projection, all circles of latitude are rhumb lines , except the Equator. The latitude of the circle is approximately the angle between the Equator and the circle, with the angle's vertex at Earth's centre. The Equator is at 0°, and the North Pole and South Pole are at 90° north and 90° south, respectively. The Equator
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#1732854834755504-591: The Southern Hemisphere , of which 5.5 percent (14 million km ) 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
546-648: 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
588-474: The Equator, mark the divisions between the five principal geographical zones . The equator is the circle that is equidistant from the North Pole and South Pole . It divides the Earth into the Northern Hemisphere and the Southern Hemisphere . Of the parallels or circles of latitude, it is the longest, and the only ' great circle ' (a circle on the surface of the Earth, centered on Earth's center). All
630-687: 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
672-599: The Tropical Circles are drifting towards the equator (and the Polar Circles towards the poles) by 15 m per year, and the area of the Tropics , defined astronomically, is decreasing by 1,100 km (420 sq mi) per year. (However, the tropical belt as defined based on atmospheric conditions is expanding due to global warming . ) The Earth's axial tilt has additional shorter-term variations due to nutation , of which
714-495: The Tropics and Polar Circles and also on the Equator. Short-term fluctuations over a matter of days do not directly affect the location of the extreme latitudes at which the Sun may appear directly overhead, or at which 24-hour day or night is possible, except when they actually occur at the time of the solstices. Rather, they cause a theoretical shifting of the parallels, that would occur if the given axis tilt were maintained throughout
756-551: 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
798-658: 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
840-522: The centre of Earth in the middle, as the circles of latitude get smaller as the distance from the Equator increases. Their length can be calculated by a common sine or cosine function. For example, the 60th parallel north or south is half as long as the Equator (disregarding Earth's minor flattening by 0.335%), stemming from cos ( 60 ∘ ) = 0.5 {\displaystyle \cos(60^{\circ })=0.5} . On
882-727: 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 Circle of latitude A circle of latitude or line of latitude on Earth
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#1732854834755924-573: The continent of Antarctica , the Kerguelen Plateau , and other island territories located on 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
966-496: 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
1008-603: The fishing vessels, as well as satellite surveillance. The islands situated between 60°S latitude parallel to 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
1050-675: 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
1092-453: 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 ,
1134-502: The horizon for 24 hours (at the December and June Solstices respectively). The latitude of the polar circles is equal to 90° minus the Earth's axial tilt . The Tropic of Cancer and Tropic of Capricorn mark the northernmost and southernmost latitudes at which the Sun may be seen directly overhead at the June solstice and December solstice respectively. The latitude of the tropical circles
1176-526: The length of the border between the United States and Canada follows 49° N . There are five major circles of latitude, listed below from north to south. The position of the Equator is fixed (90 degrees from Earth's axis of rotation) but the latitudes of the other circles depend on the tilt of this axis relative to the plane of Earth's orbit, and so are not perfectly fixed. The values below are for 22 November 2024: These circles of latitude, excluding
1218-399: The main term, with a period of 18.6 years, has an amplitude of 9.2″ (corresponding to almost 300 m north and south). There are many smaller terms, resulting in varying daily shifts of some metres in any direction. Finally, the Earth's rotational axis is not exactly fixed in the Earth, but undergoes small fluctuations (on the order of 15 m) called polar motion , which have a small effect on
1260-627: The map useful characteristics. For instance, on a Mercator projection the circles of latitude are more widely spaced near the poles to preserve local scales and shapes, while on a Gall–Peters projection the circles of latitude are spaced more closely near the poles so that comparisons of area will be accurate. On most non-cylindrical and non-pseudocylindrical projections, the circles of latitude are neither straight nor parallel. Arcs of circles of latitude are sometimes used as boundaries between countries or regions where distinctive natural borders are lacking (such as in deserts), or when an artificial border
1302-433: The mean value of the tilt was 23° 26′ 21.406″ (according to IAU 2006, theory P03), the corresponding value being 23° 26′ 10.633" at noon of January 1st 2023 AD. The main long-term cycle causes the axial tilt to fluctuate between about 22.1° and 24.5° with a period of 41,000 years. Currently, the average value of the tilt is decreasing by about 0.468″ per year. As a result (approximately, and on average),
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1344-420: The melting of the Antarctic ice sheet has a high potential to add to 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
1386-584: 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
1428-481: The northern hemisphere because astronomic latitude can be roughly measured (to within a few tens of metres) by sighting the North Star . Normally the circles of latitude are defined at zero elevation . Elevation has an effect on a location with respect to the plane formed by a circle of latitude. Since (in the geodetic system ) altitude and depth are determined by the normal to the Earth's surface, locations sharing
1470-608: The other parallels are smaller and centered only on Earth's axis. The Arctic Circle is the southernmost latitude in the Northern Hemisphere at which the Sun can remain continuously above or below the horizon for 24 hours (at the June and December solstices respectively). Similarly, the Antarctic Circle marks the northernmost latitude in the Southern Hemisphere at which the Sun can remain continuously above or below
1512-485: The poles the Sun would always circle along the horizon, and at the equator the Sun would always rise due east, pass directly overhead, and set due west. The positions of the Tropical and Polar Circles are not fixed because the axial tilt changes slowly – a complex motion determined by the superimposition of many different cycles (some of which are described below) with short to very long periods. At noon of January 1st 2000 AD,
1554-624: The region. Because the Convergence changes seasonally, the Convention for 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
1596-462: 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
1638-413: 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
1680-445: The year. These circles of latitude can be defined on other planets with axial inclinations relative to their orbital planes. Objects such as Pluto with tilt angles greater than 45 degrees will have the tropic circles closer to the poles and the polar circles closer to the equator. A number of sub-national and international borders were intended to be defined by, or are approximated by, parallels. Parallels make convenient borders in
1722-636: 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
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1764-449: 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,
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