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81-488: On 1 January 2006 the municipality had 7,487 inhabitants. The total area is 50.81 km, giving a population density of 147 inhabitants per km. The municipality consists of the following districts : Malèves-Sainte-Marie-Wastines, Orbais, Thorembais-les-Béguines, and Thorembais-Saint-Trond. In Roman times, Perwez was on the Roman road from Bavay to Cologne. This resulted in three tumuli which are no longer visible today. In 1977

162-543: A râperie , linked to a central sugar factory. The râperie was a very significant enterprise, which had 175 employees. It extracted juice from sugar beet, which was then sent by pipeline to the Wanze Sugar Factory . It was located on the Avenue de Rosaraie and closed down in 1959. Some remaining buildings are now used by a high-end restaurant. During World War II Perwez suffered from an accidental disaster. On 13 May 1940,

243-519: A French ammunition storage or mine in the center of town was hit and exploded. There were 33 casualties. The French then ignited other mines, leading to much destruction. On 6 September 1944 Perwez was liberated by the American 2nd Armored Division . There are several protected sights in Perwez. West of Thorembais-Saint-Trond there are three natural reserves:. This Walloon Brabant location article

324-410: A Russian expedition led by Fabian Gottlieb von Bellingshausen and Mikhail Lazarev . The decades that followed saw further exploration by French, American, and British expeditions. The first confirmed landing was by a Norwegian team in 1895. In the early 20th century, there were a few expeditions into the interior of the continent. British explorers Robert Falcon Scott and Ernest Shackleton were

405-569: A fast pace. Cities with high population densities are, by some, considered to be overpopulated, though this will depend on factors like quality of housing and infrastructure and access to resources. Very densely populated cities are mostly in Asia (particularly Southeast Asia ); Africa's Lagos , Kinshasa , and Cairo ; South America's Bogotá , Lima , and São Paulo ; and Mexico City and Saint Petersburg also fall into this category. City population and especially area are, however, heavily dependent on

486-517: A few blue-ice areas , the wind and sublimation remove more snow than is accumulated by precipitation. In the dry valleys, the same effect occurs over a rock base, leading to a barren and desiccated landscape. Antarctica is colder than the Arctic region, as much of Antarctica is over 3,000 m (9,800 ft) above sea level, where air temperatures are colder. The relative warmth of the Arctic Ocean

567-538: A high urbanization level, with an economically specialized city population drawing also on rural resources outside the area, illustrating the difference between high population density and overpopulation . Deserts have very limited potential for growing crops as there is not enough rain to support them. Thus, their population density is generally low. However, some cities in the Middle East, such as Dubai , have been increasing in population and infrastructure growth at

648-401: A little less than the land area of Puerto Rico , 8,868 square kilometres (3,424 sq mi). Although the arithmetic density is the most common way of measuring population density, several other methods have been developed to provide alternative measures of population density over a specific area. Antarctica Antarctica ( / æ n ˈ t ɑːr k t ɪ k ə / )

729-511: A mild climate. West Antarctica was partially in the Northern Hemisphere , and during the time, large amounts of sandstones , limestones , and shales were deposited. East Antarctica was at the equator, where seafloor invertebrates and trilobites flourished in the tropical seas. By the start of the Devonian period (416  Ma ), Gondwana was in more southern latitudes, and the climate

810-457: A native bacterial community within the subterranean water body of Lake Vostok . The existence of life there is thought to strengthen the argument for the possibility of life on Jupiter 's moon Europa , which may have water beneath its water-ice crust. There exists a community of extremophile bacteria in the highly alkaline waters of Lake Untersee . The prevalence of highly resilient creatures in such inhospitable areas could further bolster

891-665: A number of mountain ranges in the region, the most prominent being the Ellsworth Mountains. The presence of the West Antarctic Rift System has resulted in volcanism along the border between West and East Antarctica, as well as the creation of the Transantarctic Mountains. East Antarctica is geologically varied. Its formation began during the Archean Eon (4,000 Ma–2,500 Ma), and stopped during

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972-519: A tomb with several Roman artefacts was discovered near the farm of Long Pont. In Medieval times, Perwez often suffered from its position near the border between the Duchy of Brabant and the Prince-Bishopric of Liège . Perwez developed around its church and its castle, which was demolished somewhat before 1870. The main source of wealth for Perwez was its market, which relied on agricultural products. In

1053-573: Is Earth 's southernmost and least-populated continent . Situated almost entirely south of the Antarctic Circle and surrounded by the Southern Ocean (also known as the Antarctic Ocean ), it contains the geographic South Pole . Antarctica is the fifth-largest continent, being about 40% larger than Europe , and has an area of 14,200,000 km (5,500,000 sq mi). Most of Antarctica

1134-631: Is 1–3 cm (0.39–1.18 in). From the end of the Neoproterozoic era to the Cretaceous , Antarctica was part of the supercontinent Gondwana . Modern Antarctica was formed as Gondwana gradually broke apart beginning around 183 Ma. For a large proportion of the Phanerozoic , Antarctica had a tropical or temperate climate , and it was covered in forests. During the Cambrian period , Gondwana had

1215-533: Is a stub . You can help Misplaced Pages by expanding it . Population density Population density (in agriculture : standing stock or plant density ) is a measurement of population per unit land area. It is mostly applied to humans , but sometimes to other living organisms too. It is a key geographical term. Population density is population divided by total land area , sometimes including seas and oceans, as appropriate. Low densities may cause an extinction vortex and further reduce fertility. This

1296-533: Is almost 18,000 km (11,200 mi) long: as of 1983 , of the four coastal types, 44% of the coast is floating ice in the form of an ice shelf , 38% consists of ice walls that rest on rock, 13% is ice streams or the edge of glaciers, and the remaining 5% is exposed rock. The lakes that lie at the base of the continental ice sheet occur mainly in the McMurdo Dry Valleys or various oases . Lake Vostok , discovered beneath Russia's Vostok Station ,

1377-471: Is being revealed by techniques such as remote sensing , ground-penetrating radar , and satellite imagery . Geologically, West Antarctica closely resembles the South American Andes . The Antarctic Peninsula was formed by geologic uplift and the transformation of sea bed sediments into metamorphic rocks . West Antarctica was formed by the merging of several continental plates , which created

1458-478: Is called the Allee effect after the scientist who identified it. Examples of the causes of reduced fertility in low population densities are: Population density is the number of people per unit of area, usually transcribed as "per square kilometer" or square mile, and which may include or exclude, for example, areas of water or glaciers. Commonly this is calculated for a county , city , country , another territory or

1539-449: Is caused by the emission of chlorofluorocarbons and halons into the atmosphere, which causes ozone to break down into other gases. The extreme cold conditions of Antarctica allow polar stratospheric clouds to form. The clouds act as catalysts for chemical reactions, which eventually lead to the destruction of ozone. The 1987 Montreal Protocol has restricted the emissions of ozone-depleting substances. The ozone hole above Antarctica

1620-629: Is covered by the Antarctic ice sheet , with an average thickness of 1.9 km (1.2 mi). Antarctica is, on average, the coldest, driest, and windiest of the continents, and it has the highest average elevation . It is mainly a polar desert , with annual precipitation of over 200 mm (8 in) along the coast and far less inland. About 70% of the world's freshwater reserves are frozen in Antarctica, which, if melted, would raise global sea levels by almost 60 metres (200 ft). Antarctica holds

1701-631: Is divided into West Antarctica and East Antarctica by the Transantarctic Mountains , which stretch from Victoria Land to the Ross Sea . The vast majority of Antarctica is covered by the Antarctic ice sheet , which averages 1.9 km (1.2 mi) in thickness. The ice sheet extends to all but a few oases , which, with the exception of the McMurdo Dry Valleys, are located in coastal areas. Several Antarctic ice streams flow to one of

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1782-463: Is evidence of a large number of volcanoes under the ice, which could pose a risk to the ice sheet if activity levels were to rise. The ice dome known as Dome Argus in East Antarctica is the highest Antarctic ice feature, at 4,091 metres (13,422 ft). It is one of the world's coldest and driest places—temperatures there may reach as low as −90 °C (−130 °F), and the annual precipitation

1863-408: Is expected to add about 11 cm (5 in) to global sea level rise . Marine ice sheet instability may cause West Antarctica to contribute tens of centimeters more if it is triggered before 2100. With higher warming, instability would be much more likely, and could double global, 21st-century sea-level rise. The fresh, 1100-1500 billion tons (GT) per year of meltwater from the ice dilutes

1944-569: Is predicted to slowly disappear; by the 2060s, levels of ozone are expected to have returned to values last recorded in the 1980s. The ozone depletion can cause a cooling of around 6 °C (11 °F) in the stratosphere . The cooling strengthens the polar vortex and so prevents the outflow of the cold air near the South Pole, which in turn cools the continental mass of the East Antarctic ice sheet. The peripheral areas of Antarctica, especially

2025-518: Is taken into account, then human population density is 53/km (140/sq mi). This includes all continental and island land area, including Antarctica . However, if Antarctica is excluded, then population density rises to over 58 per square kilometre (150/sq mi). The European Commission's Joint Research Centre (JRC) has developed a suite of (open and free) data and tools named the Global Human Settlement Layer (GHSL) to improve

2106-441: Is the largest subglacial lake globally and one of the largest lakes in the world. It was once believed that the lake had been sealed off for millions of years, but scientists now estimate its water is replaced by the slow melting and freezing of ice caps every 13,000 years. During the summer, the ice at the edges of the lakes can melt, and liquid moats temporarily form. Antarctica has both saline and freshwater lakes. Antarctica

2187-500: Is transferred through the Arctic sea ice and moderates temperatures in the Arctic region. East Antarctica is colder than its western counterpart because of its higher elevation. Weather fronts rarely penetrate far into the continent, leaving the centre cold and dry, with moderate wind speeds. Heavy snowfalls are common on the coastal portion of Antarctica, where snowfalls of up to 1.22 m (48 in) in 48 hours have been recorded. At

2268-472: The Antarctic Circle (one of the five major circles of latitude that mark maps of the world), Antarctica is surrounded by the Southern Ocean . Rivers exist in Antarctica; the longest is the Onyx . Antarctica covers more than 14.2 million km (5,500,000 sq mi), almost double the area of Australia, making it the fifth-largest continent, and comparable to the surface area of Pluto . Its coastline

2349-641: The Beardmore Glacier by Frank Wild on the Nimrod Expedition in 1907, and low-grade coal is known to exist across many parts of the Transantarctic Mountains. The Prince Charles Mountains contain deposits of iron ore . There are oil and natural gas fields in the Ross Sea. Antarctica is the coldest, windiest, and driest of Earth's continents. Near the coast, the temperature can exceed 10 °C in summer and fall to below −40 °C in winter. Over

2430-622: The Cretaceous period (146–66 Ma), though southern beech trees ( Nothofagus ) became prominent towards the end of the Cretaceous. Ammonites were common in the seas around Antarctica, and dinosaurs were also present, though only a few Antarctic dinosaur genera ( Cryolophosaurus and Glacialisaurus , from the Early Jurassic Hanson Formation of the Transantarctic Mountains, and Antarctopelta , Trinisaura , Morrosaurus and Imperobator from Late Cretaceous of

2511-662: The Early Triassic . The Antarctic Peninsula began to form during the Jurassic period ( 206 to 146 million years ago ). Africa separated from Antarctica in the Jurassic around 160 Ma, followed by the Indian subcontinent in the early Cretaceous (about 125 Ma). Ginkgo trees, conifers, Bennettitales , horsetails , ferns and cycads were plentiful during the time. In West Antarctica, coniferous forests dominated throughout

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2592-519: 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. Scientists have studied

2673-420: The crust-like lichen Buellia frigida , has been used as a model organism in astrobiology research. The same features can be observed in algae and cyanobacteria , suggesting that they are adaptations to the conditions prevailing in Antarctica. This has led to speculation that life on Mars might have been similar to Antarctic fungi, such as Cryomyces antarcticus and Cryomyces minteri . Some of

2754-494: The entire world . The world's population is around 8,000,000,000 and the Earth 's total area (including land and water) is 510,000,000 km (200,000,000 sq mi). Therefore, the worldwide human population density is approximately 8,000,000,000 ÷ 510,000,000 = 16/km (41/sq mi). However, if only the Earth's land area of 150,000,000 km (58,000,000 sq mi)

2835-591: The modern era (1500-1800) Perwez got a cloth hall and a wheats exchange halle aux grains . In 1511 it got an annual October market. In 1577 troops paid by the rebellious States General camped near Perwez. During the Franco-Dutch War many houses and harvests were destroyed. The subsequent Nine Years' War was utterly ruinous for Perwez. During the 19th century Perwez saw quite some industrialization based on agriculture. In 1870 there were two watermills , two windmills , two tanneries , three breweries and

2916-523: The ozone layer in the atmosphere above Antarctica since the 1970s. In 1985, British scientists, working on data they had gathered at Halley Research Station on the Brunt Ice Shelf , discovered a large area of low ozone concentration over Antarctica. The 'ozone hole' covers almost the whole continent and was at its largest in September 2006; the longest-lasting event occurred in 2020. The depletion

2997-614: The Antarctic Circle on 17 January 1773, in December 1773, and again in January 1774. Cook came within about 120 km (75 mi) of the Antarctic coast before retreating in the face of field ice in January 1773. In 1775, he called the existence of a polar continent "probable", and in another copy of his journal he wrote: "[I] firmly believe it and it's more than probable that we have seen

3078-759: The Antarctic Peninsula) have been described. During the early Paleogene , Antarctica remained connected to South America as well as to southeastern Australia. Fauna from the La Meseta Formation in the Antarctic Peninsula, dating to the Eocene , is very similar to equivalent South American faunas; with marsupials , xenarthrans , litoptern , and astrapotherian ungulates , as well as gondwanatheres and possibly meridiolestidans . Marsupials are thought to have dispersed into Australia via Antarctica by

3159-423: The Antarctic Peninsula, are then subjected to higher temperatures, which accelerate the melting of the ice. Models suggest that ozone depletion and the enhanced polar vortex effect may also account for the period of increasing sea ice extent, lasting from when observation started in the late 1970s until 2014. Since then, the coverage of Antarctic sea ice has decreased rapidly. Most species in Antarctica seem to be

3240-516: The Antarctic Peninsula: Deschampsia antarctica (Antarctic hair grass), Colobanthus quitensis (Antarctic pearlwort) and the non-native Poa annua (annual bluegrass). Of the 700 species of algae in Antarctica, around half are marine phytoplankton . Multicoloured snow algae are especially abundant in the coastal regions during the summer. Even sea ice can harbour unique ecological communities, as it expels all salt from

3321-646: The Cambrian Period. It is built on a craton of rock, which is the basis of the Precambrian Shield . On top of the base are coal and sandstones, limestones, and shales that were laid down during the Devonian and Jurassic periods to form the Transantarctic Mountains. In coastal areas such as the Shackleton Range and Victoria Land, some faulting has occurred. Coal was first recorded in Antarctica near

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3402-569: The South Pole the romanised Greek name polus antarcticus , from which derived the Old French pole antartike (modern pôle antarctique ) attested in 1270, and from there the Middle English pol antartik , found first in a treatise written by the English author Geoffrey Chaucer . Belief by Europeans in the existence of a Terra Australis —a vast continent in the far south of

3483-579: The West Antarctic, the ocean has warmed by 1 °C (1.8 °F) since 1955. The warming of the Southern Ocean around Antarctica has caused the weakening or collapse of ice shelves , which float just offshore of glaciers and stabilize them. Many coastal glaciers have been losing mass and retreating, causing net-annual ice loss across Antarctica, although the East Antarctic ice sheet continues to gain ice inland. By 2100, net ice loss from Antarctica

3564-628: The argument for extraterrestrial life in cold, methane -rich environments. The first international agreement to protect Antarctica's biodiversity was adopted in 1964. The overfishing of krill (an animal that plays a large role in the Antarctic ecosystem) led officials to enact regulations on fishing. The Convention for the Conservation of Antarctic Marine Living Resources , an international treaty that came into force in 1980, regulates fisheries, aiming to preserve ecological relationships. Despite these regulations, illegal fishing —particularly of

3645-416: The biodiversity in Antarctica is still at risk from human activities. Specially protected areas cover less than 2% of the area and provide better protection for animals with popular appeal than for less visible animals. There are more terrestrial protected areas than marine protected areas . Ecosystems are impacted by local and global threats, notably pollution , the invasion of non-native species , and

3726-572: The climate cooled, though flora remained. After deglaciation during the latter half of the Early Permian , the land became dominated by glossopterids (an extinct group of seed plants with no close living relatives), most prominently Glossopteris , a tree interpreted as growing in waterlogged soils, which formed extensive coal deposits. Other plants found in Antarctica during the Permian include Cordaitales , sphenopsids , ferns, and lycophytes . At

3807-514: The colonial authorities in Sydney officially renamed the continent of New Holland to Australia, leaving the term "Terra Australis" unavailable as a reference to Antarctica. Over the following decades, geographers used phrases such as "the Antarctic Continent". They searched for a more poetic replacement, suggesting names such as Ultima and Antipodea . Antarctica was adopted in the 1890s, with

3888-497: The continent as a World Park . The Southern Ocean Whale Sanctuary was established in 1994 by the International Whaling Commission . It covers 50 million km (19 million sq mi) and completely surrounds the Antarctic continent. All commercial whaling is banned in the zone, though Japan has continued to hunt whales in the area, ostensibly for research purposes. Despite these protections,

3969-599: The continent's edge, strong katabatic winds off of the polar plateau often blow at storm force . During the summer, more solar radiation reaches the surface at the South Pole than at the equator because of the 24 hours of sunlight received there each day. 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

4050-496: 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

4131-402: The creation of small yet permanent polar ice caps. As CO 2 levels declined further the ice began to spread rapidly, replacing the forests that until then had covered Antarctica. Tundra ecosystems continued to exist on Antarctica until around 14-10 million years ago, when further cooling lead to their extermination. The geology of Antarctica, largely obscured by the continental ice sheet,

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4212-547: The definition of "urban area" used: densities are almost invariably higher for the center only than when suburban settlements and intervening rural areas are included, as in the agglomeration or metropolitan area (the latter sometimes including neighboring cities). In comparison, based on a world population of 8 billion, the world's inhabitants, if conceptualized as a loose crowd occupying just under 1 m (10 sq ft) per person (cf. Jacobs Method ), would occupy an area of 8,000 square kilometres (3,100 sq mi)

4293-549: The descendants of species that lived there millions of years ago. As such, they must have survived multiple glacial cycles . The species survived the periods of extremely cold climate in isolated warmer areas , such as those with geothermal heat or areas that remained ice-free throughout the colder climate. Invertebrate life of Antarctica includes species of microscopic mites such as Alaskozetes antarcticus , lice , nematodes , tardigrades , rotifers , krill and springtails . The few terrestrial invertebrates are limited to

4374-562: The early Eocene. Around 53 Ma, Australia- New Guinea separated from Antarctica, opening the Tasmanian Passage . The Drake Passage opened between Antarctica and South America around 30 Ma, resulting in the creation of the Antarctic Circumpolar Current that completely isolated the continent. Models of Antarctic geography suggest that this current, as well as a feedback loop caused by lowering CO 2 levels, caused

4455-479: The elevated inland, it can rise to about −30 °C in summer but fall below −80 °C in winter. The lowest natural air temperature ever recorded on Earth was −89.2 °C (−128.6 °F) at the Russian Vostok Station in Antarctica on 21 July 1983. A lower air temperature of −94.7 °C (−138.5 °F) was recorded in 2010 by satellite—however, it may have been influenced by ground temperatures and

4536-553: The end of that period. During the colder Neogene (17–2.5 Ma), a tundra ecosystem replaced the rainforests. The climate of present-day Antarctica does not allow extensive vegetation to form. A combination of freezing temperatures, poor soil quality , and a lack of moisture and sunlight inhibit plant growth, causing low species diversity and limited distribution. The flora largely consists of bryophytes (25 species of liverworts and 100 species of mosses ). There are three species of flowering plants , all of which are found in

4617-571: The end of the Permian, the climate became drier and hotter over much of Gondwana, and the glossopterid forest ecosystems collapsed, as part of the End-Permian mass extinction . There is no evidence of any tetrapods having lived in Antarctica during the Paleozoic. The continued warming dried out much of Gondwana. During the Triassic, Antarctica was dominated by seed ferns (pteridosperms) belonging to

4698-454: The first to reach the magnetic South Pole in 1909, and the geographic South Pole was first reached in 1911 by Norwegian explorer Roald Amundsen . Antarctica is governed by about 30 countries , all of which are parties of the 1959 Antarctic Treaty System . According to the terms of the treaty, military activity, mining, nuclear explosions , and nuclear waste disposal are all prohibited in Antarctica. Tourism , fishing and research are

4779-468: The first use of the name being attributed to the Scottish cartographer John George Bartholomew . Antarctica has also been known by the moniker Great White South , after which British photographer Herbert Ponting named one of his books on Antarctic photography, possibly as a counterpart to the epithet Great White North for Canada . Positioned asymmetrically around the South Pole and largely south of

4860-402: The gap of 12,000 km (7,456 mi). Large animals such as some cetaceans and birds make the round trip annually. Smaller forms of life, such as sea cucumbers and free-swimming snails , are also found in both polar oceans. Factors that may aid in their distribution include temperature differences between the deep ocean at the poles and the equator of no more than 5 °C (9 °F) and

4941-494: The genus Dicroidium , which grew as trees. Other associated Triassic flora included ginkgophytes , cycadophytes , conifers , and sphenopsids. Tetrapods first appeared in Antarctica during the early Triassic , with the earliest known fossils found in the Fremouw Formation of the Transantarctic Mountains. Synapsids (also known as "mammal-like reptiles") included species such as Lystrosaurus , and were common during

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5022-520: The globe to balance the northern lands of Europe, Asia, and North Africa—had existed as an intellectual concept since classical antiquity . The belief in such a land lasted until the European discovery of Australia . During the early 19th century, explorer Matthew Flinders doubted the existence of a detached continent south of Australia (then called New Holland ) and thus advocated for the "Terra Australis" name to be used for Australia instead. In 1824,

5103-569: The highly prized Patagonian toothfish which is marketed as Chilean sea bass in the U.S.—remains a problem. In analogy to the 1980 treaty on sustainable fishing , countries led by New Zealand and the United States negotiated a treaty on mining. This Convention on the Regulation of Antarctic Mineral Resource Activities was adopted in 1988. After a strong campaign from environmental organisations, first Australia and then France decided not to ratify

5184-536: The islands of the Kerguelen Plateau , the earliest of which formed around 40 Ma . Vinson Massif , in the Ellsworth Mountains , is the highest peak in Antarctica at 4,892 m (16,050 ft). Mount Erebus on Ross Island is the world's southernmost active volcano and erupts around 10 times each day. Ash from eruptions has been found 300 kilometres (190 mi) from the volcanic crater . There

5265-467: The main human activities in and around Antarctica. During the summer months, about 5,000 people reside at research stations , a figure that drops to around 1,000 in the winter. Despite the continent's remoteness, human activity has a significant effect on it via pollution , ozone depletion , and climate change . The melting of the potentially unstable West Antarctic ice sheet causes the most uncertainty in century-scale projections of sea level rise , and

5346-814: The major current systems or marine conveyor belts which are able to transport eggs and larva . About 1,150 species of fungi have been recorded in the Antarctic region, of which about 750 are non- lichen -forming. Some of the species, having evolved under extreme conditions, have colonised structural cavities within porous rocks and have contributed to shaping the rock formations of the McMurdo Dry Valleys and surrounding mountain ridges. The simplified morphology of such fungi, along with their similar biological structures , metabolism systems capable of remaining active at very low temperatures, and reduced life cycles, make them well suited to such environments. Their thick-walled and strongly melanised cells make them resistant to UV radiation. An Antarctic endemic species,

5427-653: The many Antarctic ice shelves , a process described by ice-sheet dynamics . East Antarctica comprises Coats Land , Queen Maud Land , Enderby Land , Mac . Robertson Land , Wilkes Land , and Victoria Land. All but a small portion of the region lies within the Eastern Hemisphere . East Antarctica is largely covered by the East Antarctic Ice Sheet . There are numerous islands surrounding Antarctica, most of which are volcanic and very young by geological standards. The most prominent exceptions to this are

5508-573: The north'). Antarcticus is derived from the Greek ἀντι- ('anti-') and ἀρκτικός ('of the Bear ', 'northern'). The Greek philosopher Aristotle wrote in Meteorology about an "Antarctic region" in c.  350 BCE . The Greek geographer Marinus of Tyre reportedly used the name in his world map from the second century CE, now lost. The Roman authors Gaius Julius Hyginus and Apuleius used for

5589-564: The ocean around Antarctica, including some that normally reside in the Arctic. The emperor penguin is the only penguin that breeds during the winter in Antarctica; it and the Adélie penguin breed farther south than any other penguin. A Census of Marine Life by some 500 researchers during the International Polar Year was released in 2010. The research found that more than 235 marine organisms live in both polar regions, having bridged

5670-424: The record for the lowest measured temperature on Earth , −89.2 °C (−128.6 °F). The coastal regions can reach temperatures over 10 °C (50 °F) in the summer. Native species of animals include mites , nematodes , penguins , seals and tardigrades . Where vegetation occurs, it is mostly in the form of lichen or moss . The ice shelves of Antarctica were probably first seen in 1820, during

5751-526: 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 the full effects are expected to occur over multiple centuries; these include less precipitation in the Southern Hemisphere but more in

5832-476: The same melting also affects the Southern Ocean overturning circulation , which can eventually lead to significant impacts on the Southern Hemisphere climate and Southern Ocean productivity. The name given to the continent originates from the word antarctic , which comes from Middle French antartique or antarctique ('opposite to the Arctic ') and, in turn, the Latin antarcticus ('opposite to

5913-545: The science for policy support to the European Commission Directorate Generals and Services and as support to the United Nations system. Several of the most densely populated territories in the world are city-states , microstates and urban dependencies . In fact, 95% of the world's population is concentrated on just 10% of the world's land. These territories have a relatively small area and

5994-406: The species of fungi, which are apparently endemic to Antarctica, live in bird dung, and have evolved so they can grow inside extremely cold dung, but can also pass through the intestines of warm-blooded animals. Throughout its history, Antarctica has seen a wide variety of plant life. In the Cretaceous , it was dominated by a fern- conifer ecosystem, which changed into a temperate rainforest by

6075-683: The sub-Antarctic islands. The flightless midge Belgica antarctica , the largest purely terrestrial animal in Antarctica, reaches 6 mm ( 1 ⁄ 4  in) in size. Antarctic krill , which congregates in large schools , is the keystone species of the ecosystem of the Southern Ocean, being an important food organism for whales, seals, leopard seals , fur seals, squid , icefish , and many bird species, such as penguins and albatrosses . Some species of marine animals exist and rely, directly or indirectly, on phytoplankton . Antarctic sea life includes penguins , blue whales , orcas , colossal squids and fur seals . The Antarctic fur seal

6156-572: The treaty. Instead, countries adopted the Protocol on Environmental Protection to the Antarctic Treaty (the Madrid Protocol), which entered into force in 1998. The Madrid Protocol bans all mining, designating the continent as a "natural reserve devoted to peace and science". The pressure group Greenpeace established a base on Ross Island from 1987 to 1992 as part of its attempt to establish

6237-464: The various effects of climate change . Early world maps, like the 1513 Piri Reis map , feature the hypothetical continent Terra Australis . Much larger than and unrelated to Antarctica, Terra Australis was a landmass that classical scholars presumed necessary to balance the known lands in the northern hemisphere. Captain James Cook 's ships, HMS  Resolution and Adventure , crossed

6318-412: The water when it freezes, which accumulates into pockets of brine that also harbour dormant microorganisms. When the ice begins to melt, brine pockets expand and can combine to form brine channels, and the algae inside the pockets can reawaken and thrive until the next freeze. Bacteria have also been found as deep as 800 m (0.50 mi) under the ice. It is thought to be likely that there exists

6399-517: Was cooler, though fossils of land plants are known from then. Sand and silts were laid down in what is now the Ellsworth, Horlick , and Pensacola Mountains . Antarctica became glaciated during the Late Paleozoic icehouse beginning at the end of the Devonian period (360 Ma), though glaciation would substantially increase during the late Carboniferous . It drifted closer to the South Pole, and

6480-472: Was not recorded at a height of 2 m (7 ft) above the surface as required for official air temperature records. Antarctica is a polar desert with little precipitation ; the continent receives an average equivalent to about 150 mm (6 in) of water per year, mostly in the form of snow. The interior is dryer and receives less than 50 mm (2 in) per year, whereas the coastal regions typically receive more than 200 mm (8 in). In

6561-496: Was very heavily hunted in the 18th and 19th centuries for its pelt by seal hunters from the United States and the United Kingdom. Leopard seals are apex predators in the Antarctic ecosystem and migrate across the Southern Ocean in search of food. There are approximately 40 bird species that breed on or close to Antarctica, including species of petrels , penguins , cormorants , and gulls . Various other bird species visit

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