Arctic

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For the ships, see MV Arctic, SS Arctic, USS Arctic. For other uses, see Arctic (disambiguation)
Location of the Arctic
Artificially coloured topographical map of the Arctic region
MODIS image of the Arctic

The Arctic (/ˈɑrktɪk/ or /ˈɑrtɪk/) is a polar region located at the northernmost part of the Earth. The Arctic consists of the Arctic Ocean and parts of Canada, Russia, the United States (Alaska), Denmark (Greenland), Norway, Sweden, Finland, and Iceland. The Arctic region consists of a vast ocean with a seasonally varying ice cover, surrounded by treeless permafrost. The area can be defined as north of the Arctic Circle (66° 33'N), the approximate limit of the midnight sun and the polar night. Alternatively, it can be defined as the region where the average temperature for the warmest month (July) is below 10 °C (50 °F); the northernmost tree line roughly follows the isotherm at the boundary of this region.[1][2]

Socially and politically, the Arctic region includes the northern territories of the eight Arctic states, although by natural science definitions much of this territory is considered subarctic. The Arctic region is a unique area among Earth's ecosystems. The cultures in the region and the Arctic indigenous peoples have adapted to its cold and extreme conditions. In recent years the extent of the sea ice has declined.[3][4] Life in the Arctic includes organisms living in the ice,[5] zooplankton and phytoplankton, fish and marine mammals, birds, land animals, plants and human societies.

Etymology[edit]

The word Arctic comes from the Greek ἀρκτικός (arktikos), "near the Bear, northern"[6] and that from the word ἄρκτος (arktos), meaning bear.[7] The name refers either to the constellation Ursa Major, the "Great Bear", which is prominent in the northern portion of the celestial sphere, or to the constellation Ursa Minor, the "Little Bear", which contains Polaris, the Pole Star, also known as the North Star.[8]

Climate[edit]

Main article: Climate of the Arctic

The Arctic's climate is characterized by cold winters and cool summers. Precipitation mostly comes in the form of snow. The Arctic's annual precipitation is low, with most of the area receiving less than 50 cm (20 in). High winds often stir up snow, creating the illusion of continuous snowfall. Average winter temperatures can be as low as −40 °C (−40 °F), and the coldest recorded temperature is approximately −68 °C (−90 °F). Coastal Arctic climates are moderated by oceanic influences, having generally warmer temperatures and heavier snowfalls than the colder and drier interior areas. The Arctic is affected by current global warming, leading to Arctic sea ice shrinkage and Arctic methane release.

Due to the poleward migration of the planet's isotherms (about 35 mi (56 km) per decade during the past 30 years as a consequence of global warming), the Arctic region (as defined by tree line and temperature) is currently shrinking.[9] Perhaps the most spectacular result of Arctic shrinkage is sea ice loss. There is a large variance in predictions of Arctic sea ice loss, with models showing near-complete to complete loss in September from 2040 to some time well beyond 2100. About half of the analyzed models show near-complete to complete sea ice loss in September by the year 2100.[3]

Flora and fauna[edit]

Plants[edit]

Arctic vegetation is composed of plants such as dwarf shrubs, graminoids, herbs, lichens and mosses, which all grow relatively close to the ground, forming tundra. As one moves northward, the amount of warmth available for plant growth decreases considerably. In the northernmost areas, plants are at their metabolic limits, and small differences in the total amount of summer warmth make large differences in the amount of energy available for maintenance, growth and reproduction. Colder summer temperatures cause the size, abundance, productivity and variety of plants to decrease. Trees cannot grow in the Arctic, but in its warmest parts, shrubs are common and can reach 2 m (6 ft 7 in) in height; sedges, mosses and lichens can form thick layers. In the coldest parts of the Arctic, much of the ground is bare; non-vascular plants such as lichens and mosses predominate, along with a few scattered grasses and forbs (like the arctic poppy).

Animals[edit]

Herbivores on the tundra include the Arctic hare, lemming, muskox, and caribou. They are preyed on by the Snowy owl, Arctic fox and wolf. The polar bear is also a predator, though it prefers to hunt for marine life from the ice. There are also many birds and marine species endemic to the colder regions. Other land animals include wolverines, ermines, and Arctic ground squirrels. Marine mammals include seals, walrus, and several species of cetaceanbaleen whales and also narwhals, killer whales and belugas.

Natural resources[edit]

The Arctic includes sizable natural resources (oil, gas, minerals, fresh water, fish and if the subarctic is included, forest) to which modern technology and the economic opening up of Russia have given significant new opportunities. The interest of the tourism industry is also on the increase.

The Arctic is one of the last and most extensive continuous wilderness areas in the world, and its significance in preserving biodiversity and genotypes is considerable. The increasing presence of humans fragments vital habitats. The Arctic is particularly susceptible to the abrasion of groundcover and to the disturbance of the rare reproduction places of the animals that are characteristic to the region. The Arctic also holds 1/5 of the Earth's water supply.[citation needed]

Paleo-history[edit]

During the Cretaceous, the Arctic still had seasonal snows, though only a light dusting and not enough to permanently hinder plant growth.[citation needed] Animals such as Chasmosaurus, Hypacrosaurus, Troodon, and Edmontosaurus may have all migrated north to take advantage of the summer growing season, and migrated south to warmer climes when the winter came. A similar situation may also have been found amongst dinosaurs that lived in Antarctic regions, such as Muttaburrasaurus of Australia.

Indigenous population[edit]

Main article: Arctic peoples

The earliest inhabitants of North America's central and eastern Arctic are referred to as the Arctic small tool tradition (AST) and existed c. 2500 BC. AST consisted of several Paleo-Eskimo cultures, including the Independence cultures and Pre-Dorset culture.[10][11] The Dorset culture (Inuktitut: Tuniit or Tunit) refers to the next inhabitants of central and eastern Arctic. The Dorset culture evolved because of technological and economic changes during the period of 1050–550 BC. With the exception of the Quebec/Labrador peninsula, the Dorset culture vanished around 1500 AD.[12] Supported by genetic testing, evidence shows that Dorset culture, known as the Sadlermiut, survived in Aivilik, Southampton and Coats Islands, until the beginning of the 20th century.[13]

Dorset/Thule culture transition dates around the 9th–10th centuries. Scientists theorize that there may have been cross-contact of the two cultures with sharing of technology, such as fashioning harpoon heads, or the Thule may have found Dorset remnants and adapted their ways with the predecessor culture.[14] Others believe the Thule displaced the Dorset. By 1300, the Inuit, present-day Arctic inhabitants and descendants of Thule culture, had settled in west Greenland, and moved into east Greenland over the following century. Over time, the Inuit have migrated throughout the Arctic regions of Canada, Greenland, Russia and the United States.[15]

Other Circumpolar North indigenous peoples include the Buryat, Chukchi, Evenks, Inupiat, Khanty, Koryaks, Nenets, Sami, Yukaghir, and Yupik, who still refer to themselves as Eskimo which means "snowshoe netters", not "raw meat eaters" as it is sometimes mistakenly translated.[16]

International cooperation and politics[edit]

Polar bears on the sea ice of the Arctic Ocean, near the North Pole. USS Honolulu pictured.

The eight Arctic nations (Canada, Denmark (Greenland & The Faroe Islands), Finland, Iceland, Norway, Sweden, Russia, and USA) are all members of the Arctic Council, as are organizations representing six indigenous populations. The Council operates on consensus basis, mostly dealing with environmental treaties and not addressing boundary or resource disputes.

Though Arctic policy priorities differ, every Arctic nation is concerned about sovereignty/defense, resource development, shipping routes, and environmental protection. Much work remains on regulatory agreements regarding shipping, tourism, and resource development in Arctic waters.[17]

Research in the Arctic has long been a collaborative international effort, evidenced perhaps most notably by the International Polar Year. The International Arctic Science Committee, hundreds of scientists and specialists of the Arctic Council, and the Barents Euro-Arctic Council are more examples of collaborative international Arctic research.

Territorial claims[edit]

No country owns the geographic North Pole or the region of the Arctic Ocean surrounding it. The surrounding Arctic states that border the Arctic Ocean — Canada, Denmark (via Greenland), Iceland, Norway, Russia, and the United States —are limited to a 200 nautical miles (370 km; 230 mi) economic zone around their coasts.

Upon ratification of the United Nations Convention on the Law of the Sea, a country has ten years to make claims to an extended continental shelf beyond its 200 nautical mile zone.[18] Due to this, Norway (which ratified the convention in 1996),[19] Russia (ratified in 1997),[19] Canada (ratified in 2003)[19] and Denmark (ratified in 2004)[19] launched projects to establish claims that certain sectors of the Arctic seabed should belong to their territories.

On August 2, 2007, two Russian bathyscaphes, MIR-1 and MIR-2, for the first time in history descended to the Arctic seabed beneath the North Pole and placed there a Russian flag made of rust-proof titanium alloy. The mission was a scientific expedition, but the flag-placing during Arktika 2007, raised concerns of a race for control of the Arctic's vast petroleum resources.[20]

Foreign ministers and other officials representing Canada, Denmark, Norway, Russia, and the United States met in Ilulissat, Greenland on May 28, 2008 at the Arctic Ocean Conference and announced the Ilulissat Declaration,[21][22] blocking any "new comprehensive international legal regime to govern the Arctic Ocean," and pledging "the orderly settlement of any possible overlapping claims."[23]

As of 2012, Denmark is claiming the continental shelf between Greenland and the North Pole.[24] The Russian Federation is claiming a large swath of seabed along the Lomonosov Ridge but confined to its sector of the Arctic.

Exploration[edit]

Main article: Arctic exploration

Since 1937, the whole Arctic region has been extensively explored by Soviet and Russian manned drifting ice stations. Between 1937 and 1991, 88 international polar crews established and occupied scientific settlements on the drift ice and were carried thousands of kilometers by the ice flow.[25]

Pollution[edit]

Long-range pollution pathways to the Arctic

The Arctic is comparatively clean, although there are certain ecologically difficult localized pollution problems that present a serious threat to people's health living around these pollution sources. Due to the prevailing worldwide sea and air currents, the Arctic area is the fallout region for long-range transport pollutants, and in some places the concentrations exceed the levels of densely populated urban areas. An example of this is the phenomenon of Arctic haze, which is commonly blamed on long-range pollutants. Another example is with the bioaccumulation of PCB's (polychlorinated biphenyls) in Arctic wildlife and people.

Preservation[edit]

Main article: Save the Arctic

There have been many proposals to preserve the Arctic over the years. Most recently a group of stars at the Rio Earth Summit, on June 21, 2012, proposed protecting the Arctic, similar to the Antarctic protection. The initial focus of the campaign will be a UN resolution creating a global sanctuary around the pole, and a ban on oil drilling and unsustainable fishing in the Arctic.[26]

Climate change[edit]

Arctic sea ice coverage as of 2007 compared to 2005 and compared to 1979–2000 average
The development of Arctic sea ice area as measured with satellites.[27]
The development of Arctic sea ice volume as estimated by measurement corrected numerical simulation shows probability of total sea ice loss in summer for the near future.[28]

The Arctic is especially vulnerable to the effects of global warming, as has become apparent in the melting sea ice in recent years. Climate models predict much greater warming in the Arctic than the global average,[29] resulting in significant international attention to the region. In particular, there are concerns that Arctic shrinkage, a consequence of melting glaciers and other ice in Greenland, could soon contribute to a substantial rise in sea levels worldwide.[30] The climate models on which the IPCC report Nr.4 is based give a range of predictions of Arctic sea ice loss, showing near-complete to complete loss in September anywhere from 2040 to some time well beyond 2100. About half of the analyzed models show near-complete to complete sea ice loss in September by the year 2100.[3] More recently, the Catlin Arctic Survey concluded that summer ice loss would occur around 2029.[31][32] It has been apparent though since 2007, that those models grossly underestimate sea ice loss.[33]

As can be seen in the two plot at the right, since about 1995 to 2000, all three size numbers of the Arctic sea ice shield (extent, area and volume) are decreasing in an accelerated way. This downward movement is modulated by statistical variations, which lead to considerable media attention, when a new record has been reached.

Concerning melting records, 2012 was a productive year, thus corroborating the tendency of the past decade. This may have been furthered by a strong summer storm cyclone, a rare event in the Arctic, which spread the already very thin ice and caused mixing of the cold surface waters with deeper warmer water layers. According to the University of Bremen, in September 2011 the Arctic ice cap was smaller than ever recorded (the satellite measurements started in the 1970s).[34][35] Arctic ice is declining in area and thinning. Arctic temperatures have risen more than twice as fast as the global average over the past half century. The speed of change has shocked scientists. If current trends continue, a largely ice-free Arctic in the summer is likely within 30 years – up to 40 years earlier than was anticipated by the IPCC Fourth Assessment Report.[36]

As the volume of sea ice until recently could not be measured by remote sensing as easy as its extent, numerical models have been made to estimate the ice thickness field between known points, which then is summed up to yield ice volume. The resulting volume over time reveals a much stronger loss of ice than ice extent studies suggest.[28]

The current Arctic shrinkage is leading to fears of Arctic methane release.[37] Release of methane stored in permafrost could cause abrupt and severe global warming,[38] as methane is a potent greenhouse gas. On millennial time-scales, decomposition of methane hydrates in the Arctic seabed could also amplify global warming.[citation needed] Previous methane release events have been linked to the great dying, a mass extinction event at the boundary of the Permian and Triassic, and the Paleocene–Eocene Thermal Maximum, in which temperatures abruptly increased.

Apart from concerns regarding the detrimental effects of warming in the Arctic, some potential opportunities have gained attention. The melting of the ice is making the Northwest Passage, the shipping routes through the northernmost latitudes, more navigable, raising the possibility that the Arctic region will become a prime trade route.[39] In addition, it is believed that the Arctic seabed may contain substantial oil fields which may become accessible if the ice covering them melts.[40] These factors have led to recent international debates as to which nations can claim sovereignty or ownership over the waters of the Arctic.[41][42][43][44]

The National Oceanic and Atmospheric Administration's Arctic Report Card[45] presents annually updated, peer-reviewed information on recent observations of environmental conditions in the Arctic relative to historical records.

Eidsfjord in Vesterålen, Norway is 250 km (160 mi) inside the Arctic Circle, but the comparatively temperate Norwegian sea gives a mean annual temperature of 4 °C (39 °F) and a three-month summer above 10°C.[46]

Arctic waters[edit]

Arctic lands[edit]

Geographic DesignationNational AffiliationDesignation
AlaskaUnited StatesState
Aleutian IslandsUnited StatesAlaskan Archipelago
Arkhangelsk OblastRussiaFederal subject
Canadian Arctic ArchipelagoCanadaCanadian Archipelago
Diomede Island (Big)RussiaIsland
Diomede Island (Little)United StatesIsland
FinnmarkNorwayCounty
Franz Josef LandRussiaFederal subject archipelago
GreenlandDenmarkAutonomous country
GrímseyIcelandIsland
Jan MayenNorwayIsland
LaplandFinlandRegion
LaplandSwedenProvince
New Siberian IslandsRussiaArchipelago
NordlandNorwayCounty
NorrbottenSwedenProvince
Northwest TerritoriesCanadaTerritory
Novaya ZemlyaRussiaFederal subject archipelago
NunavikCanadaNorthern part of Quebec
NunavutCanadaTerritory
Russian Arctic islandsRussiaIslands
SápmiNorway, Sweden, Finland, RussiaFennoscandia region
Sakha RepublicRussiaFederal subject
Severnaya ZemlyaRussiaFederal subject archipelago
SiberiaRussiaRegion
SvalbardNorwayGovernor of Svalbard archipelago
TromsNorwayCounty
YukonCanadaTerritory
Wrangel IslandRussiaZapovednik (nature reserve)


See also[edit]

References[edit]

  1. ^ "arctic." Dictionary.com Unabridged (v 1.1). Random House, Inc. Retrieved on May 2, 2009.
  2. ^ Addison, Kenneth (2002). Fundamentals of the physical environment. Routledge. p. 482. ISBN 0-415-23293-7. 
  3. ^ a b c Serreze, Mc; Holland, Mm; Stroeve, J (Mar 2007). "Perspectives on the Arctic's shrinking sea-ice cover". Science 315 (5818): 1533–6. Bibcode:2007Sci...315.1533S. doi:10.1126/science.1139426. PMID 17363664. 
  4. ^ "Global Sea Ice Extent and Concentration: What sensors on satellites are telling us about sea ice." National Snow and Ice Data Center. Retrieved May 1, 2009.
  5. ^ Christopher Krembs and Jody Deming. "Organisms that thrive in Arctic sea ice." National Oceanic and Atmospheric Administration. November 18, 2006.
  6. ^ Henry George Liddell and Robert Scott. "Arktikos." A Greek-English Lexicon. Perseus Digital Library.
  7. ^ Henry George Liddell and Robert Scott. "Arktos." A Greek-English Lexicon. Perseus Digital Library.
  8. ^ "The Great Bear Constellation Ursa Major". Archived from the original on 30 November 2010. Retrieved 2010-11-10. 
  9. ^ Hansen, Jim (October 19, 2006). "The Planet in Peril – Part I". Yale Center for the Study of Globalization. 
  10. ^ Hoffecker, John F. (2005). A prehistory of the north: human settlement of the higher latitudes. Rutgers University Press. p. 130. ISBN 0-8135-3469-0. 
  11. ^ Gibbon, pp. 28–31
  12. ^ Gibbon, pp. 216–217
  13. ^ McGhee, Robert (2005). The last imaginary place: a human history of the Arctic world (Digitized October 7, 2008 ed.). Oxford University Press. p. 55. ISBN 0-19-518368-1. 
  14. ^ Gibbon, p. 218
  15. ^ "First Nations Culture Areas Index". the Canadian Museum of Civilization. 
  16. ^ "Arctic Peoples". British Museum. 
  17. ^ Berkman, Paul (2014-06-23). "Stability and Peace in the Arctic Ocean through Science Diplomacy". Science & Diplomacy 3 (2). 
  18. ^ "United Nations Convention on the Law of the Sea (Annex 2, Article 4)". Archived from the original on 16 July 2007. Retrieved 2007-07-26. 
  19. ^ a b c d "Chronological lists of ratifications of, accessions and successions to the Convention and the related Agreements". United Nations Division for Ocean Affairs and the Law of the Sea. April 22, 2009. Archived from the original on 14 April 2009. Retrieved April 30, 2009. 
  20. ^ Shamil Midkhatovich Yenikeyeff and Timothy Fenton Krysiek. The Battle for the Next Energy Frontier: The Russian Polar Expedition and the Future of Arctic Hydrocarbons. Oxford Institute for Energy Studies, August 2007.
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  23. ^ Boswell, Randy (2008-05-28). "Conference could mark start of Arctic power struggle". canada.com. Retrieved 2008-06-06. 
  24. ^ http://www.nrk.no/nyheter/verden/1.8261208 "Danskenes påstand er at Grønlands kontinentalsokkel strekker seg helt til Nordpolen, som derfor bør være dansk."
  25. ^ "North Pole drifting stations (1930s–1980s)". Woods Hole Oceanographic Institution. Retrieved April 30, 2009. 
  26. ^ Stars launch campaign to save the Arctic. Greenpeace (2012-06-21).
  27. ^ Fetterer, F., K. Knowles, W. Meier, and M. Savoie. 2002, updated 2009. Sea Ice Index. Boulder, Colorado USA: National Snow and Ice Data Center. Digital media.
  28. ^ a b Zhang, Jinlun and D.A. Rothrock (2003). "Modeling global sea ice with a thickness and enthalpy distribution model in generalized curvilinear coordinates". Mon. Wea. Rev. 131 (5): 681–697. Bibcode:2003MWRv..131..845Z. doi:10.1175/1520-0493(2003)131<0845:MGSIWA>2.0.CO;2. 
  29. ^ Impacts of a warming Arctic: Arctic Climate Impact Assessment. Cambridge, UK: Cambridge University Press. February 2005. doi:10.2277/0521617782. ISBN 0-521-61778-2. 
  30. ^ Grinberg, Emanuella. "Ice melting across globe at accelerating rate, NASA says." CNN. December 17, 2008.
  31. ^ "Catlin Arctic Survey – Science and Expedition Summary". Catlin Arctic Survey. 
  32. ^ Richard A. Kerr (28 September 2012). "Ice-Free Arctic Sea May be Years, Not Decades, Away". Science 337: 1591. Bibcode:2012Sci...337.1591K. doi:10.1126/science.337.6102.1591. 
  33. ^ Stroeve et al., "Arctic sea ice decline: Faster than forecast", GEOPHYSICAL RESEARCH LETTERS, VOL. 34, L09501, doi: 10.1029/2007GL029703, 2007
  34. ^ "Arctic Sea Ice News and Analysis". NSIDC. 2011-09-13. 
  35. ^ "Report: Arctic sea ice coverage second lowest on record". Reuters. 2011-09-13. 
  36. ^ Vidal, John (2011-09-11). "Arctic sea ice is melting at its fastest pace in almost 40 years". The Guardian. Archived from the original on 2012-08-24. 
  37. ^ Lenton, T. M.; Held, H.; Kriegler, E.; Hall, J. W.; Lucht, W.; Rahmstorf, S.; Schellnhuber, H. J. (2008). "Inaugural Article: Tipping elements in the Earth's climate system". Proceedings of the National Academy of Sciences 105 (6): 1786. doi:10.1073/pnas.0705414105.  edit
  38. ^ "Abrupt Climate Change Focus Of U.S. National Laboratories". Science Daily. 2008-09-23. 
  39. ^ "Will ice melt open fabled Northwest Passage?" CNN. August 29, 2002.
  40. ^ Demos, Telis. "The great Arctic Circle oil rush." CNN. August 8, 2007.
  41. ^ Shaw, Rob. "New patrol ships will reassert northern sovereignty: PM". Victoria Times Colonist. July 9, 2007.
  42. ^ Halpin, Tony. "Russia stakes its claim on North Pole in underwater search for oil". Times Online. July 28, 2007.
  43. ^ "Arctic melt stuns scientists". CBS News. 2007-10-09. 
  44. ^ "Conference could mark start of Arctic power struggle". Canada.com. 2008-05-28. 
  45. ^ Arctic Report Card. Arctic.noaa.gov. Retrieved on 2011-10-18.
  46. ^ Stokmarknes in Vesterålen 1961–1990 average. Retro.met.no (2008-01-28). Retrieved on 2011-10-18.

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