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107-1018: McMurdo Station is an American Antarctic research station on the southern tip of Ross Island , which is in the New Zealand –claimed Ross Dependency on the shore of McMurdo Sound in Antarctica. It is operated by the United States through the United States Antarctic Program (USAP), a branch of the National Science Foundation . The station is the largest community in Antarctica, capable of supporting up to 1,500 residents, and serves as one of three year-round United States Antarctic science facilities. All personnel and cargo going to or coming from Amundsen–Scott South Pole Station first pass through McMurdo. McMurdo Station continues to operate as

214-736: A Department of the Army Approved Qualitative Materiel Development Objective for Nuclear Power Plants, dated 7 January 1965, these objectives were stated for the program: The AEC ultimately concluded that the probability of achieving the objectives of the Army Nuclear Power Program in a timely manner and at a reasonable cost was not high enough to justify continued funding of its portion of projects to develop small, stationary, and mobile reactors. Cutbacks in military funding for long-range research and development because of

321-410: 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

428-527: 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

535-469: A few months had its signal received as far as the US east coast. AFAN had changed frequencies several times in subsequent years. The station continued broadcasting on shortwave into the 1980s when it dropped shortwave while continuing FM transmission. For a time, McMurdo had Antarctica's only television station, AFAN-TV, running vintage programs provided by the military. Broadcasts started on November 9, 1973, with

642-417: A few times every year, often as early as May, and sometimes even as early as April, and very rarely above 0 °C. The highest temperature ever recorded at McMurdo was 10.8 °C on December 21, 1987. There is enough snowmelt in summer that a few species of moss and lichen can grow. Starting in 1963, McMurdo played host to one of the only two shortwave broadcast stations in Antarctica. From sign-on to 1971,

749-525: 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

856-470: A mix of US programs and interviews with visitors and scientists, as well as a daily news and weather service. The station's equipment was susceptible to "electronic burping" from the diesel generators that provide electricity in the outpost. The station was profiled in a 1975 article in TV Guide magazine, where the station broadcast in the summer months, known by staff as "the season" (November to February),

963-457: 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

1070-701: 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

1177-521: A part of it". Army Nuclear Power Program There was interest in the possible application of nuclear power to land-based military needs as early as 1952. A memo from the Secretary of Defense , dated 10 February 1954, assigned the Army the responsibility for "developing nuclear power plants to supply heat and electricity at remote and relatively inaccessible military installations." The Secretary of

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1284-485: A polar ice cap climate ( Köppen EF ). However, in the warmest months (December and January) the monthly average high temperature may occasionally rise above freezing. The place is protected from cold waves from the interior of Antarctica by the Transantarctic Mountains , so temperatures below −40° are rare, compared to more exposed places like Neumayer Station , which usually gets those temperatures

1391-476: A proprietary, non-replaceable part critical to battery storage reduced the power generation of the turbines by 66% by 2019. Between 1962 and 1963, 28 Arcas sounding rockets were launched from McMurdo Station. McMurdo Station stands about two miles (3 km) from Scott Base , the New Zealand science station, and all of Ross Island lies within a sector claimed by New Zealand. Criticism has been leveled at

1498-501: A rally. As of 2007, McMurdo Station was Antarctica's largest community and a functional, modern-day science station, including a harbor , three airfields (two seasonal), a heliport and more than 100 buildings, including the Albert P. Crary Science and Engineering Center . The station is also home to the continent's two ATMs , both provided by Wells Fargo Bank . The work done at McMurdo Station primarily focuses on science , but most of

1605-655: 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

1712-463: Is about 45 cm × 60 cm (18 in × 24 in) in size, and is secured to a large vertical rock halfway up the west side of Observation Hill , at the former site of the PM-3A nuclear power reactor at McMurdo Station. The inscription details the achievements of Antarctica's first nuclear power plant. It has been designated a Historic Site or Monument (HSM 85), following a proposal by

1819-542: 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 ,

1926-480: 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

2033-449: 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

2140-635: 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

2247-470: 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

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2354-408: 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

2461-582: 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

2568-441: 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

2675-504: 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

2782-588: The Antarctic Treaty System (ATS), opened for signature on December 1, 1959, and officially entered into force on June 23, 1961. The first scientific diving protocols were established before 1960 and the first diving operations were documented in November 1961. On March 3, 1962, the U.S. Navy activated the PM-3A nuclear power plant at the station. The unit was prefabricated in modules to facilitate transport and assembly. Engineers designed

2889-605: 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

2996-499: 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 is covered by the Antarctic ice sheet , with an average thickness of 1.9 km (1.2 mi). Antarctica is, on average,

3103-662: 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

3210-641: 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

3317-723: The Department of Defense to obtain special nuclear material for use in defense utilization facilities. The focus of the Army Nuclear Power Program was on power production facilities while the Naval Reactors Program concentrated on nuclear propulsion for submarines and ships. On 9 April 1954 the Chief of Engineers established the US Army Engineer Reactors Group to perform the missions assigned by DA. Essentially, these missions were to: In

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3424-683: 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

3531-526: 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

3638-420: 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

3745-789: The gallery of photos in the next section. Sources for this data include the only known book on the ANPP, by Suid, and a DOE document. In 1961, after the SL-1 plant explosion, General Alvin Luedecke , the General Manager of the AEC, temporarily prevented the startup of the PM-2A until an interlock could be installed on the central control rod. While the interlock could be operated by personnel, General Luedecke would have to be notified first. The PM-2A

3852-535: 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

3959-637: 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

4066-790: 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

4173-423: 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

4280-529: 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

4387-679: The Army established the Army Nuclear Power Program and assigned it to the Corps of Engineers . The Atomic Energy Act of 1954 made the Atomic Energy Commission (AEC) responsible for R&D in the nuclear field, so that the ANPP then became a joint interagency 'activity' of the Department of the Army (DA) and the AEC. When the Atomic Energy Act was revised in 1954, Paragraph 91b authorized

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4494-674: 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

4601-701: The DOE document, the Suid book, and the Briefing Book. The Nuclear Power Plant Operator Course (NPPOC) was conducted at Ft. Belvoir. Applicants for the program were enlisted men who had to commit to serving a minimum of two years after completion of training. The requirements for admission to the NPPOC included aptitude test scores at least as stringent as those required for admission to Officer Candidate School. Over 1,000 Nuclear Power Plant operators were licensed between

4708-714: The End of the World reports on the life and culture of McMurdo Station from the point-of-view of residents. Anthony Powell's 2013 documentary Antarctica: A Year on Ice provides time-lapse photography of Antarctica intertwined with personal accounts from residents of McMurdo Station and of the adjacent Scott Base over the course of a year. An annual sealift by cargo ships as part of Operation Deep Freeze delivers 8 million U.S. gallons (6.6 million imperial gallons/42 million liters) of fuel and 11 million pounds (5 million kg) of supplies and equipment for McMurdo residents. The ships, operated by

4815-456: The IGY, it became the center for US scientific as well as logistical activities in Antarctica. The Antarctic Treaty , subsequently signed by over forty-five governments, regulates intergovernmental relations with respect to Antarctica and governs the conduct of daily life at McMurdo for United States Antarctic Program (USAP) participants. The Antarctic Treaty and related agreements, collectively called

4922-587: 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

5029-533: The U.S. Military Sealift Command , are crewed by civilian mariners. Cargo may range from mail, construction materials, trucks, tractors, dry and frozen food, to scientific instruments. U.S. Coast Guard icebreakers break a ship channel through ice-clogged McMurdo Sound in order for supply ships to reach Winter Quarters Bay at McMurdo. Additional supplies and personnel are flown into nearby Williams Field from Christchurch in New Zealand. With all months having an average temperature below freezing, McMurdo features

5136-510: The U.S. Navy Seabees , was initially designated Naval Air Facility McMurdo . On November 28, 1957, Admiral George J. Dufek visited McMurdo with a U.S. congressional delegation for a change-of-command ceremony. McMurdo Station was the center of United States logistical operations during the International Geophysical Year , an international scientific effort that lasted from July 1, 1957, to December 31, 1958. After

5243-591: The US. Voice communications within the station are conducted via VHF radio. Testing of the Starlink service began in September 2022, with a second terminal providing connectivity for the Allan Hills field camp brought in November 2022. The Starlink test ran from January to March of 2023, when it was shut off indefinitely to analyze test data. McMurdo has the world's most southerly harbor. A multitude of on- and off-road vehicles transport people and cargo around

5350-534: The United States to the Antarctic Treaty Consultative Meeting . Facilities at the station include: Once a year around New Year's Day Icestock , the most southern music festival is organized, with performers being from the station and Scott Base . Antarctica Antarctica ( / æ n ˈ t ɑːr k t ɪ k ə / ) is Earth 's southernmost and least-populated continent . Situated almost entirely south of

5457-530: The Vietnam War led the AEC to phase out its support of the program in 1966. The costs of developing and producing compact nuclear power plants were so high that they could be justified only if the reactor had a unique capability and filled a clearly defined objective backed by DOD. After that, the Army's participation in nuclear power plant research and development efforts steadily declined and eventually stopped altogether. Eight plants were constructed. Due to

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5564-593: 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

5671-502: The area in 1841. The British explorer Robert Falcon Scott established a base camp close to this spot in 1902 and built a cabin there that was named Discovery Hut . It still stands as a historic monument near the water's edge on Hut Point at McMurdo Station. The volcanic rock of the site is the southernmost bare ground accessible by ship in the world. The United States officially opened its first station at McMurdo on February 16, 1956, as part of Operation Deep Freeze . The base, built by

5778-634: 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

5885-624: The base regarding its construction projects, particularly the McMurdo-(Amundsen-Scott) South Pole highway . McMurdo Station has attempted to improve environmental management and waste removal in order to adhere to the Protocol on Environmental Protection to the Antarctic Treaty , signed on October 4, 1991, which entered into force on January 14, 1998. This agreement prevents development and provides for

5992-416: 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

6099-451: The callsign was KMSA, from then on it was changed to WASA (W A ntarctic S upport A ctivities), later changing to AFAN in 1975. As KMSA, the station broadcast in the same building as the bowling alley, the barber shop and the retail store. A part of the vinyl collection reportedly came from Vietnam, believing to have been played by Adrian Cronauer 's show in Saigon. In a 1997 interview to The Antarctic Sun , Cronauer denied these claims and

6206-466: 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

6313-399: 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

6420-404: 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

6527-409: The components to weigh no more than 30,000 pounds (14,000 kg) each and to measure no more than 8 feet 8 inches (2.64 m) by 8 feet 8 inches (2.64 m) by 30 feet (9.1 m). A single core no larger than an oil drum served as the heart of the nuclear reactor . These size and weight restrictions aimed to allow delivery of the reactor in an LC-130 Hercules aircraft, but

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6634-426: The components were delivered by ship. The reactor generated 1.8 MW of electrical power and reportedly replaced the need for 1,500 US gallons (5,700 L) of oil daily. Engineers applied the reactor's power, for instance, in producing steam for the salt-water distillation plant. As a result of continuing safety issues (hairline cracks in the reactor and water leaks), the U.S. Army Nuclear Power Program decommissioned

6741-423: 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,

6848-599: 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

6955-496: 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

7062-402: 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,

7169-549: 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

7276-432: 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

7383-414: 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

7490-553: 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

7597-415: 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

7704-454: 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

7811-473: 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

7918-402: 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

8025-502: 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

8132-525: 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,

8239-519: 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

8346-476: The hub for American activities on the Antarctic continent. By road, McMurdo is 3 kilometres (1.9 mi) from New Zealand 's smaller Scott Base . The station takes its name from its geographic location on McMurdo Sound , named after Lieutenant Archibald McMurdo of British ship HMS  Terror . The Terror , commanded by Irish explorer Francis Crozier , along with expedition flagship Erebus under command of English Explorer James Clark Ross , first charted

8453-412: The ice from 1989 to 2006. A hyperbaric chamber is available for support of polar diving operations. McMurdo Station briefly gained global notice when an anti-war protest took place on February 15, 2003. During the rally, about 50 scientists and station personnel gathered to protest against the coming invasion of Iraq by the United States. McMurdo Station was the only Antarctic location to hold such

8560-553: 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

8667-467: 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

8774-814: 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,

8881-671: 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

8988-587: 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

9095-578: 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

9202-410: The only season where Antarctica was (at the time) open to aircraft. In the mid-90s, a cable network was installed. By 1998, shortly after the launch of new AFN television services the year before, the traditional AFN network was broadcast over cable channel 2 (the channel that would soon become AFN Prime), NewSports (the current AFN News and AFN Sports) was on channel 11 and Spectrum (current AFN Spectrum)

9309-483: The plant in 1972. Conventional diesel generators replaced the nuclear power station, with several 500 kilowatts (670 hp) diesel generators in a central powerhouse providing electric power. A conventionally fueled water-desalination plant provided fresh water. Three Enercon E-33 (330 kW each) wind turbines were deployed in 2009 to power McMurdo and New Zealand's Scott Base, reducing diesel consumption by 11% or 463,000 liters per year. The subsequent failure of

9416-425: The protection of the Antarctic environment through five specific annexes on marine pollution , fauna and flora , environmental impact assessments , waste management , and protected areas . It prohibits all activities relating to mineral resources except scientific ones. A new waste-treatment facility was built at McMurdo in 2003. Scientific diving operations continue with 10,859 dives having been conducted under

9523-424: 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

9630-643: The requirement for a small physical size, all these reactors other than the MH-1A used highly enriched uranium ( HEU ). The MH-1A had more space to work with, and more weight-carrying capacity, so this was a low-enrichment reactor; i.e., larger and heavier. The MH-1A was briefly considered for use in Vietnam, but the idea of anything nuclear in Vietnam was quickly rejected by the State Department. The plants are listed in order of their initial criticality. See

9737-464: The residents (approximately 1,000 in the summer and around 250 in the winter) are not scientists, but station personnel who provide support for operations, logistics, information technology, construction, and maintenance. Scientists and other personnel at McMurdo are participants in the USAP, which coordinates research and operational support in the region. Werner Herzog 's 2007 documentary Encounters at

9844-539: 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

9951-480: 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

10058-406: 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

10165-667: The station area, including Ivan the Terra Bus (a pun on Ivan the Terrible ). There is a road from McMurdo to the New Zealand Scott Base and South Pole, the South Pole Traverse . McMurdo station is serviced seasonally from Christchurch Airport about 3,920 kilometres (2,440 mi) away by air, with C-17 Globemaster and Lockheed LC-130 , by three airports: The Richard E. Byrd Historic Monument

10272-683: 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

10379-470: 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

10486-470: 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

10593-470: The vinyl collection was apparently destroyed. The station—AFAN McMurdo—initially operated on AM 600 and had a power of 50 W, but by 1974, it transmitted with a power of 1 kilowatt on the shortwave frequency of 6,012 kHz and became a target for shortwave radio listening to hobbyists around the world because of its rarity. The station was picked up by DX for the first time in New Zealand in July 1974, and within

10700-412: 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

10807-475: Was also used to investigate neutron embrittlement in carbon steel. This plant was shut down 1963–1964. However despite the reactor's successes, Project Iceworm was never fielded and Camp Century was later abandoned. Key to the codes: Of the eight built, six produced operationally useful power for an extended period. Many of the designs were based on United States Naval reactors , which were proven compact reactor designs. References for this list include

10914-529: 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

11021-454: Was erected at McMurdo in 1965. It includes a bronze bust on black marble , 150 cm × 60 cm (5 ft × 2 ft) square, on a wooden platform, bearing inscriptions describing the polar exploration achievements of Richard E. Byrd . It has been designated a Historic Site or Monument (HSM 54), following a proposal by the United States to the Antarctic Treaty Consultative Meeting . The bronze Nuclear Power Plant Plaque

11128-472: 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

11235-561: Was on channel 13. McMurdo Station receives both Internet and voice communications by satellite communications via the Optus D1 satellite and relayed to Sydney, Australia. A satellite dish at Black Island provides 20 Mbit/s Internet connectivity and voice communications. Voice communications are tied into the United States Antarctic Program headquarters in Centennial, Colorado , providing inbound and outbound calls to McMurdo from

11342-524: Was the only reactor besides SL-1 that had a central control rod that could startup the reactor on its own. We gave explicit instructions on the 8th of January that this reactor, which was shut down at the time, would not be started until we had reviewed the situation. It was necessary for us to issue instructions to modify mechanisms of the PM-2A so that no single rod could be raised to a point where criticality could automatically occur. PM-2A successfully powered Camp Century for three years. The pressure vessel

11449-503: 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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