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46-492: There are two main types of polynyas: coastal polynyas, which can be found year-round near the Antarctic and Arctic coasts and are mainly created by strong winds pushing the ice away from the coast, and mid-sea or open-ocean polynyas, which may be found more sporadically in the middle of ice pack in certain locations, especially around Antarctica. These locations are generally preconditioned by certain oceanic dynamics. One of

92-470: A frozen world. This provides food for Arctic cod , a species that plays a critical role in supporting the entire ecosystem. Large concentrations of marine mammals , from walrus to seals and polar bears , feed at the ice edge until spring break-up. The same habitat provides vital feeding grounds for millions of seabirds, including an estimated two-thirds of the world population of little auk (dovekie) and thick-billed murres . This region has been home to

138-526: A large amount of brine rejection into the surface waters; this salty water then sinks. It is an open question as to whether the polynyas of the Arctic can produce enough dense water to form a major portion of the dense water required to drive the thermohaline circulation . Mid-sea polynyas are formed when specific atmospheric conditions occur over preconditioned oceanographic areas. Such atmospheric conditions should favor ice drift in opposite directions to open

184-693: A polar ecosystem warming twice as fast as the rest of the world. The North Water Polynya (Pikialasorsuaq/Saqvaaq) is closely connected to Lancaster Sound ( Inuktitut ᑕᓪᓗᕈᑎᐅᑉ ᑕᕆᐅᖓ Tallurutiup Tariunga ) and the Baffin Bay by a powerful system of ocean currents that directly affect the region's climate and biology. In a sense, the NOW polynya is a result of the merging of three smaller polynya's Smith Sound, Lady Ann Strait , and Lancaster Sound . The West Greenland Current follows that country's coastline and moves warm and salty Atlantic water north, reaching all

230-412: A polynya. The presence of open water in an otherwise ice-covered area can result in a localized marine algal bloom , also referred to as a polynya bloom. While algal communities are often found under sea ice , as evidenced by ice algae , the rate of phytoplankton growth is substantially higher in the open water of a polynya. The primary drivers of polynya blooms are sunlight and nutrients. Specifically,

276-433: A result of containing more phytoplankton than the surrounding water. Therefore, due to the role of primary producers as the foundation of the marine food web , polynyas are a critical food source for a variety of organisms such as fish, birds, and marine mammals. Listed below are several examples of the importance of polynyas to polar communities. Polynyas have also supported human populations throughout history. For example,

322-470: A socially inclusive approach to meeting area-based conservation and Marine Protected Area targets." An Indigenous Peoples' Organization membership and voting category was also added at that congress. The only present protection is a 1983 promise by Denmark and Canada to develop "further bilateral cooperation in respect of the protection of the marine environment of the waters lying between Canada and Greenland and of its living resources..." In April 2016,

368-750: A special Pikialaorsuaq Commission led by the Inuit Circumpolar Council began collecting input of residents in the High Arctic communities of Canada and Greenland on future protections of the North Water Polynya. In April 2017 a Canadian report entitled “A new Shared Arctic Leadership Model” by Mary Simon recommended that Canada accept the Pikialasorsuaq Commission's recommendation for the creation of an Inuit-led management plan and monitoring process for

414-799: Is a polar region around Earth 's South Pole , opposite the Arctic region around the North Pole . The Antarctic comprises the continent of Antarctica , the Kerguelen Plateau , and other island territories located on 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

460-455: Is a polynya (area of year-round open water surrounded by sea ice ) that lies between Greenland and Canada in northern Baffin Bay . The world's largest Arctic polynya at about 85,000 km (33,000 sq mi), it creates a warm microclimate that provides a refuge for narwhal , beluga , walrus , and bowhead whales to feed and rest. While thin ice forms in some areas, the polynya

506-599: 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

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552-546: Is credited to the Spaniard Gabriel de Castilla , who reported seeing distant southern snow-capped mountains in 1603. The first Antarctic land discovered was the island of South Georgia , visited by the English merchant Anthony de la Roché in 1675. Although such myths and speculation about a Terra Australis ("Southern Land") date back to antiquity, the first confirmed sighting of the continent of Antarctica

598-459: Is kept open by wind, tides and an ice bridge on its northern edge. Named the "North Water" by 19th century whalers who relied on it for spring passage, this polynya is one of the most biologically productive marine areas in the Arctic Ocean . Polynyas are often compared to oases as their open waters allow for an unusually early spring plankton bloom and an open water wintering area in

644-428: Is low on the islands: studies have theorized that 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

690-491: Is managed through an international commission headquartered in Hobart , Australia, by an efficient system of annual fishing quotas, licenses, and international inspectors on the fishing vessels, as well as satellite surveillance. The islands situated between 60°S latitude parallel to the south and the Antarctic Convergence to the north and their respective 200-nautical-mile (370 km) exclusive economic zones fall under

736-763: Is no permanent country in Antarctica . As defined by the Antarctic Treaty System , the Antarctic region is everything south of the 60°S latitude . The Treaty area covers Antarctica and 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

782-722: Is set to expire in 35 years. ) To protect 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

828-496: The Antarctic Convergence , a zone approximately 32 to 48 km (20 to 30 mi) wide and varying in latitude seasonally. The region covers some 20 percent of the Southern Hemisphere , of which 5.5 percent (14 million km ) 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 ,

874-440: The Antarctic realm is one of eight biogeographic realms on Earth's land surface. Climate change in Antarctica is particularly important because the melting of the Antarctic ice sheet has a high potential to add to 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

920-500: The North Water Polynya , the largest and most biologically productive Arctic polynya, serves as a critical source of food in an otherwise barren region, enabling the existence of high-latitude human communities in the region for thousands of years. It may have served as a stepping stone for the original settlers of Greenland as they traversed through what is now northern Canada 4500 years ago. There are also indications that

966-400: The Southern Ocean . It plays a major role in the global overturning circulation. Coastal polynyas (latent heat polynyas) are a source of AABW as brine rejection during the formation of sea ice at these polynyas increases the salinity of the seawater, which then sinks down to the ocean bottom as AABW. Antarctic polynyas form when ice masses diverge from the coast and move away in the direction of

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1012-483: The 15th and 19th centuries, European whalers arrived and hunted bowhead whales to the brink of extinction. Since 1867 the North Water ecosystem has been a favourite study site for Western scientists trying to unlock the oceanographic and biological secrets of Arctic polynyas. Researchers have also conducted intensive studies on the region's response to global climate change because of its mid-Arctic latitude amidst

1058-540: The Convergence and thus outside the Antarctic region. A variety of animals live in Antarctica for at least some of 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

1104-720: The Inuit of Greenland (Avannaata) rely on the abundance of marine life in North Water for their food, clothing, shelter, and essential cultural and economic well-being. There is evidence that the North Water was visited by the Vikings in southern Greenland in the 13th century. It wasn't until 1616 that the Discovery , captained by Robert Bylot and piloted by William Baffin , sailed into this region, naming its landmarks such as Sir Thomas Smith's Bay (now Smith Sound) and Lancaster Sound after those who financed their expeditions. Between

1150-402: The North Water Polynya has aided Thule , Inuit , Norse , and western explorers throughout history. Today, the North Water Polynya enables the existence of Greenland's northernmost towns, such as Qaanaaq , Qeqertat , Savissivik and Siorapaluk . When submarines of the U.S. Navy made expeditions to the North Pole in the 1950s and 1960s, there was significant concern about surfacing through

1196-562: 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

1242-523: The cold waters of the Southern Ocean collide with the warmer waters of the north, forming a natural border to the region. Because the Convergence changes seasonally, the Convention for 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

1288-916: 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 North Water Polynya The North Water Polynya (NOW), or Pikialasorsuaq to Inuit in Greenland and Sarvarjuaq to Inuit in Canada,

1334-496: 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

1380-752: 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

1426-409: The ice pack. Polar cyclones are a typical atmospheric trigger for the occurrence of mid-sea polynyas as the cyclonic winds push the ice in opposite directions away from the cyclone center. Also, cold fronts, where two opposite flows in direction are found, are ideal for creating a mid-sea polynya. Antarctic bottom water (AABW) is the dense water with high salinity that exists in the abyssal layer of

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1472-523: The lack of sea ice allows light, a necessary component for photosynthesis , to penetrate deeper into the water and enable elevated phytoplankton growth compared to the surrounding ice-covered waters. Furthermore, polynya formation is typically associated with upwelling , a process that transports nutrient-rich water from the ocean bottom towards the surface. This influx of nutrients coupled with increased light levels often results in polynya blooms. In general, polynyas tend to be more biologically productive as

1518-856: The most famous mid-sea polynyas is the Weddell Polynya , also known as the Maud Rise Polynya, which occurs in the Lazarev Sea over the Maud Rise seamount. It was first spotted in September 1973 and persisted through multiple winters (1974–1976), and recently recurred in September 2017. Coastal polynyas are formed through two main processes: Latent heat polynyas are regions of high ice production and therefore are possible sites of dense water production in both polar regions . The high ice production rates within these polynyas leads to

1564-607: The most popular destinations being the Antarctic Peninsula area (especially the South Shetland Islands ) and South Georgia Island . In December 2009, the growth of tourism , with consequences for both the ecology and the safety of the travellers in its great and remote wilderness, was noted at a conference in New Zealand by experts from signatories to the Antarctic Treaty . The definitive results of

1610-843: 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 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

1656-678: The northernmost human settlements in the world for at least 5,000 years, through the Dorset and Thule cultural migrations. Present-day Inuit communities in Canada (Nunavut) and Avanersuaq (Greenland) rely on the polynya's concentration of marine mammals to sustain their traditional way of life. The North Water is home to the northernmost self-sufficient human settlements in the world, and borders three Qikiqtani Inuit communities in Canada: Arctic Bay , Pond Inlet and Grise Fiord . These Inuit communities in Canada (Nunavut), along with

1702-467: The southernmost. In late 1977, Silvia Morella de Palma, who was then seven months pregnant, was airlifted to Esperanza Base , in order to complete her pregnancy in the base. The airlift was a part of the Argentine solutions to the sovereignty dispute over territory in Antarctica. Emilio was automatically granted Argentine citizenship by the government since his parents were both Argentine citizens, and he

1748-623: The thick pack ice of the Arctic Ocean. In 1962, both the USS Skate and USS Seadragon surfaced within the same large polynya near the North Pole for the first polar rendezvous of the U.S. Atlantic Fleet and the U.S. Pacific Fleet . 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 / )

1794-483: The waters of the North Water polynya have not been given any formal protection. In 1982 the western waters in Lancaster Sound were listed as one of the greatest 188 natural areas in the world, and one of the only sites in the Arctic to get this recognition. Two sites within Lancaster Sound were chosen as the top 219 "The World's Greatest Natural Areas" by international work groups that met from 1980 to 1982. Of

1840-595: The way to the North Water Polynya. An upwelling of warmer water in this polynya helps keep it partially ice-free throughout the year, even when the ocean directly north and south is frozen. Another arm of the West Greenland Current reaches into Lancaster Sound, delivering Atlantic waters into the Arctic Ocean and contributing to that area's rich ecology. The lands adjacent to the North Water have been recognized internationally for their importance. In 1974 Denmark created Northeast Greenland National Park ,

1886-633: The wind, creating an exposed area of sea water which subsequently freezes over, with brine rejection, to form another mass of ice. Some polynyas, such as the North Water Polynya between Canada and Greenland , occur seasonally at the same time and place each year. Because animals can adapt their life strategies to this regularity, these types of polynyas are of special ecological research significance. In winter, marine mammals such as walruses , narwhals , and belugas that do not migrate south remain there. Polar bears are known to be able to swim as far as 65 kilometres (35 nautical miles) across open waters of

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1932-588: The world quality Nearctic sites listed, 31 years later only the two Lancaster Sound sites have not achieved national or provincial protection (nor any IUCN category Level I-VI of protection). There are presently no World Heritage Sites above the 73rd parallel north . At the 2012 IUCN Conservation Congress in Korea a resolution was passed calling on the International Union for Conservation of Nature (IUCN) to "promote Locally Managed Marine Areas as

1978-407: The world's largest national park in northeast Greenland. In 1977 it was designated an international biosphere reserve . Likewise, Canada created Canada's second largest national park, Quttinirpaaq in 1988 on the adjacent Ellesmere Island . Twelve percent of the world's land is protected, but only 1.6 percent of the global ocean area is protected. In a time of increasing Arctic industrial activity

2024-766: The world's largest protected area comprising 1.07 million km , 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

2070-661: 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

2116-449: 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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