The Arctic is the northernmost region of the Earth. Centering on the North Pole, the region includes the Arctic Ocean, the northernmost sections of North America and Eurasia, and the numerous islands and archipelagoes that fringe the northern coasts of these two continents. The region thus encompasses all of Greenland (a Danish terrtory) and all the northern parts of Canada, Alaska (U.S.), Russia, Finland, Sweden, and Norway. The major islands are those of the Canadian Archipelago (including Baffin, Banks, Ellesmere, Victoria, Sverdrup, Parry, Prince of Wales, and Axel Hieberg); the Norwegian island group of Svalbard (including Spitsbergen); and Franz Josef Land, Novaya Zemlya, and the New Siberian Islands, all of which are part of Russia. Whether Iceland is placed within, or excluded from, the Arctic depends on the criteria used to define the southern limit of the region.
The southern limit of the Arctic region is most commonly placed at the Arctic Circle (lat. 66 degrees 30' N); because of the way the Earth spins around the Sun on a tilted axis of rotation, this is also the southernmost limit of the midnight Sun, or 24-hour summer day. Some experts, however, regard the tree line (the southern edge of the TUNDRA and the northern limit of tree growth) as the edge of the Arctic. Others place the edge of the region along the 10 degrees C (50 degrees F) isotherm (a line connecting points of equal temperature) for the warmest month of the year, or along the - 4 degrees C (25 degrees F) annual isotherm.
The name Arctic is derived from the Greek word arktos meaning "bear," and is a reference to the constellation Ursa Major, or Great Bear, which appears prominently in the northern sky.
The Arctic, unlike Antarctica, is mostly free of snow and ice cover in the summer months. Glaciers are common throughout the archipelagoes, but the only permanent ice sheet, that of Greenland, is about one-eighth the size of the Antarctic ice sheet. In the Arctic snow is subject to melting and evaporation rnore than in Antarctica, and thus ice buildup is less, The region's long, cold winters do produce an all-year layer of drifting ice, 7 m (16-23 ft) thick, on the central (and some coastal) areas of the Arctic ocean. This ice covers a larger area in winter than in summer, but open water exists even in the winter months.
PERMAFROST, or permanently frozen ground, occurs in all Arctic lands and commonly extends to a depth hundreds of meters below the surface. In Siberia permafrost reaches depths greater than 1,500 m (5,000 ft), although in northern Alaska the maximum depth is about 600 m (2,000 ft). The permafrost prevents or impedes drainage. In warmer areas a shallow layer may thaw in summer, and the meltwater will form vast marshy areas and myriad lakes that dot the coastal plains. Such areas afford nesting sites for migratory birds.
At one time or another during the Pleistocene Epoch (2,000,000 to 10,000 years ago), rnost of the Arctic was covered by ice sheets, although some areas such as northern Alaska and parts of Siberia appear to have escaped glaciation. Glaciation dissected the existing mountain ranges, but the Arctic was a region of low average elevation before the Pleistocene Epoch began.
The continental fringes bordering the Arctic Ocean in both North America and Eurasia are generally low-lying. Four of the world's major rivers--the Mackenzie in North America and the Lena, Ob, and Yenisei in Eurasia--flow north to the Arctic ocean through the northern continental plains.
By contrast, many of the Arctic islands are relatively rugged, and low mountains rise precipitously from the sea. In the Canadian Archipelago the mountains range in height from about 2,000 m (6,600 ft) in the eastern islands of Baffin, Devon, Ellesmere, and Axel-Heiberg-- which are the four islands where the principal glaciers of the archipelago are found-- to only a few hundred meters above sea level in the westem islands. This highest point of the archipelago is Barbeau Peak, which rises 2,604 m (8,544 ft) on Ellesmere Island.
Greenland, located to the east of the Canadian Archipelago, is also rugged, rising to a high point of 3,700 m (12,139 ft) at Mount Gunnbjorn on the east coast. Approximately 80 percent of Greenland is covered by ice.
In Eurasia the most westerly of the Arctic islands is Svalbard, located to the north of Norway. Svalbard includes several groups of islands lying between 74 degrees and 81 degrees north latitude, with a total area of about 62,050 sq km (23,958 sq mi); it rises to a high point of 1,717 m (5,633 ft) In Newtontoppen on West Spitsbergen. More than half of all Svalbard is buried under glaciers. Franz Josef Land, located east-northeast of Svalbard, is an archipelago lying between 80 degrees and 82 degrees north latitude, with a total ares of about 16,090 sq km (6,212 sq mi), about 85 percent of which is under ice. Novaya Zemlya, off the coast of Russia, has an area of about 82,621 sq km (31,900 sq mi), one-fourth of which is ice-covered; Sedova, which rises to 1,591 m (5,220 ft), is the highest point.
Severnaya Zemlya, an archipelago located north of central Siberia, has a total area of 36,713 sq km (14,175 sq mi), about half of which is covered with ice, and a high point of 965 m (3,166 ft) on Oktyabrskoy Revolyutsii Island. The New Siberian Isiands, located off the coast of eastern Siberia. have a total area of 37,555 sq km (14,500 sq mi), and, although the highest point is only 374 m (1,227 ft) above sea level, small glaciers are found in the northeastern islands.
The Arctic is the site of many valuable mineral deposits. Russia mines gold, tin, tungsten, diamonds, nickel, copper, and coal in the Arctic. Coal is mined in Svalbard, and iron ore is mined In northern Sweden. In 1968 vast oil and natural-gas deposits were found on the North Slope at PRUDHOE BAY, Alaska. Geologic exploration continues throughout the North American Arctic. Alaska's Arctic National Wildlife Refuge is believed to contain significant reserves of oil but is closed to drilling because of environmental concerns.
Climatically, the Arctic is a cold desert-- that is, it receives (with local exceptions) less than 250 mm (10 in) of precipitation annually. Indeed, some areas of the Arctic, such as Pealy Land in northern Greenland, are drier than the world's tropical deserts. Generally, precipitation ranges from 250 mm (10 in) in the southern regions to less than 125 mm (5 in) in the north. Most precipitation falls as snow (an annual average of about 300-600 mm/12-14 in) in the autumn and the early spring.
Arctic winters are long and cold, and summers are short and cool. The region receives minimal solar heat owing to the low angle at which the Sun's rays strike the Earth even during the long summer days; in winter the Sun does not rise above the horizon.
The Arctie Ocean, which receives relatively warm north-flowing currents from the Atlantic and Pacific, acts as a moderating influence, especially on the surrounding shores and islands. A temperature INVERSION exists over the region during much of the year, the result of relatively warm air coming into contact with a lower layer cooled by the ground. In summer, especially, this is associated with cloud cover and fog. Smog, probably from Eurasian industrial areas, has accumulated over parts of the Arctic; some scientists think such pollution will affect the climate. Thinning of the OZONE LAYER above the Arctic has also been observed.
The Greenland ice sheet and the Arctic Ocean maintain cold temperatures throughout the year, but the tundra-covered coastal fringes warm up each summer for a brief period. Minimum temperatures of - 70 degrees C (- 94 degrees F) are approached or reached in Greenland and have been recorded at Verkhoyansk, in Siberia; maximum temperatures of about - 5 degrees C (23 degrees F) to 2 degrees C (36 degrees F) are common on the ice sheet, and highs of 20 degrees -40 degrees C (70 degrees-100 degrees F) on land areas. The annual temperature range is greatest in parts of Slberia, approaching 100 C degrees (180 F degrees). Arctic winds are less prevalent and strong than those of Antarctica, but coasts are subject to cyclonic storms.
Robert F. Black
FLORA AND FAUNA
Despite the Arctic's harsh environment, the zone contains a varied plant and animal life. Cycles of overpopulation and food scarcity characterize Arctic ecology. Humans living in the Arctic have long had a stable relationship with their environrnent, but modern technology threatens this relationship.
Arctic plants have evolved many specialized adaptations for life on the windswept tundra, with its low precipitation and long, severe winters. Trees and shrubs that grow there are much smaller than related forms to the south, and their tissues are far more resistant to freezing and thawing. (The recent discovery of a fossil forest in the Canadian Arctic indicates that trees were more substantial in the past.) Arctic plants have short roots because of permafrost. Mosses and lichens are the most common plant life, the lichens helping to break down surface rocks into soil. During the brief summer grasses and attractive flowering plants appear, sometimes completing their entire life cycle within one month.
The buds of many Arctic plants grow just above or below the suface of the soil and are protected by plant parts remaining from former years. Only three species survive the winter in seed form. Because many kinds of asexual reproduction occur and self-pollination predominates, genetic variation is slight within Arctic plant species. The plants are dispersed by wind, water, and migratory animals.
Arctic animal life is more familiarly represented by the polar bear, which roams the snow and ice, and the caribou, which migrates in vast herds across the tundra in search of food. The migratory routes of caribou in North America have been disrupted by oil-pipeline construction, The caribou and the reindeer of northem Europe and Asia, once considered different species, are now classified as one. Besides caribou and polar bears, large Arctic land mammals include other bears and musk- oxen. Among the several small Arctic land mammals are rodent such as voles and lemmings; weasels such as ermines, martins, and sables; foxes; squirrels; and hares.
Arctic sea mammals such as the narwhal, walrus, seal, and sea lion usually migrate, but fish such as cod, salmon, and char are found in Arctic waters and below the ice cap throughout the year. Insects and other invertebrate species inhabit milder regions of the zone. Generally, the adult insect forms stay below the snow in winter, but their eggs and pupae can survive below the surface. The high GLYCEROL content of some adult insects enables them to withstand extreme cold without freezing. The absence of predatory reptiles, together with the long summer days and the abundance of insects, makes the tundra an ideal breeding place for ground-nesting birds. These include many kinds of waterfowl, sandpipers, plovers, and some hawks, ptarmigans, cranes, owls, larks, and finches.
As the Arctic winter approaches, all herbivorous mammals and many carnivores acquire fat reserves. The caribou has a prominent layer of back fat extending from shoulders to rump and often equal to one-sixth of the body weight. Besides acting as an energy reserve, the fat serves as excellent insulation. The hair seals and walrus, lacking a dense coat of furl, are equipped with a thick blubber layer, as are the Arctic whales. In addition to fat, the larger land mammals have thick coats of fur. The musk-ox's body is covered with a deep, dense wool called quivut-- the most valuable raw fiber in the world-- over which lie long, coarse guard hairs. A dominant characteristic of most Arctic animals is their white color, the degree of which is related to the winter climate in a given region. Some animals are white the year round, such as the polar bear and snowy owl, and others alternate with a darker summer color, such as the Arctic fox. The color helps conceal both predator and prey in winter. It was formerly believed to reduce the loss of body heat, but experiments apparently have disproved this.
R. R. Riewe
The harsh Arctic environment supports a sparse but varied population. In North America the principal Arctic inhabitants are the small numbers of miners, technicians, and government workers who come north for short periods of service and a far larger number of ESKIMO, or, as they prefer to be called, Inuit.
The Eskimos a people of Mongoloid origin, are believed to have lived in the Arctic since their first migration from Asia at least 10,000 years ago. Although traditionally dependent on hunting seals, walruses, whales, and migrating caribou, many Eskimo now live in government camps and are employed in mining and other nontraditional activities.
The principal inhabitants of the European Arctic are the LAPPS, a people of Finno-Ugrian origin, who now occupy the northern parts of Norway, Sweden, Finland, and northwestern Russia, collectively referred to as Lapland. Once primarily nomadic reindeer hunters inland and fishernen along the coast, the Lapps have in recent years turned to reindeer herding and breeding and to farming and other sedentary activities as the wild reindeer have declined in number.
The Arctic reaches of central and northeastern Russia are occupied by numerous ethnic groups, including a small number of Eskimo, CHUKCHI, SAMOYED, and YAKUT.
The recorded history of the Arctic lands dates from the early 9th century when, according to Icelandic sagas, Irish monks were living in Iceland. In about 850, Norsemen settled in Iceland. The first reported sighting of Greenland was by Gunnbjorn UIfsson, but the credit for actual exploration of the island goes to ERIC THE RED, who visited the western coast about 982 and, in about 986, set up a colony in the southwestern part of the island that survived for several centuries. Spitsbergen was discovered in 1194 and was used as a base by Norsemen who explored eastward as far as the island Novaya Zemlya.
In the 15th and 16th centuries, in their search for a northern sea toute to China, explorers rediscovered many of the Arctic islands. Martin FROBISHER, who commanded the first (1576) of numerous British expeditions charged with finding a NORTHWEST PASSAGE, discovered in the course of his voyages Frobisher Bay in southern Baffin Island and accurately mapped for the first time parts of Greenland and the Canadian Archipelago.
Wellem BARENTS, a Dutch navigator for whom the Barents Sea is named, searched for a NORTHEAST PASSAGE in 1596-97. His expedition rediscovered Spitsbergen and wintered on Novaya Zemlya, the first European explorers to survive the hardships of an Artic winter. Henry HUDSON led the first expedition to survive the winter (1610-11) in Hudson Bay
In 1671, Friedrich Martens, a German surgeon, wrote an account of the landscape and natural history of Spitsbergen that was the standard reference work on the islands until William Scoresby, Jr.'s famous Account of the Arctic Regions was published in 1820.
Exploration of the Russian Arctic occurred during the conquest of Siberia beginning In the 17th century. Between 1728 and 1741, Vitus BERING, a Dane in Russian service, became the first to sail through the strait between Asia and North Arnerica that now bears his name.
The 19th century saw a renewed interest in Arctic exploration. In 1818, Sir William Edward PARRY and Sir John Ross retraced the 1615-16 voyage of William BAFFlN and opened up an extensive area of Baffin Bay to whaling interests. In 1831, Sir James Clark ROSS, a nephew of John Ross, became the first man to reach the north magnetic pole.
In 1847, Sir John FRANKLIN became the first man to find a sea passage through the North American Arctic, but it was blocked by ice and unnavigable. Franklin's ship was caught in ice between Victoria and King William islands. After his death the members of his party set out on foot, and all perished. Relief expeditions sent out to find or learn the fate of the missing Franklin party brought much new knowledge of the region. on one such expedition, Sir Robert McClure made the first traverse (1853) of a route by foot and boat that, if not icebound, would have realized the British dream of a Northwest Passage. Richard Collinson discovered another sea route, but it, too, was icebound and unnavigable. Interest in the Eurasian Arctic was similarly renewed in the 19th century, and in 1878-79, Adolf Erik Nordenskjold successfully navigated the Northeast Passage for the first time.
Toward the end of the 19th century international polar conferences In 1879 and 1880 advanced the idea of international cooperation in conducting systematic meteorologic and magnetic observations in the Arctic. Starting in 1882, observation stations were set up by several countries, including the United States, Norway, Sweden, Denmark, Russia, Great Britain, Germany, and Austria.
In 1888, Fridtjof NANSEN, Otto Sverdrup, and others became the first people known to have crossed Greenland. In 1893, Nansen and Sverdrup sailed the Fram into the Arctic Ocean pack ice off the New Siberian Islands and allowed the ship, frozen into the ice, to drift for three years across the ocean. The scientific observations completed during this drift set new standards for oceanographic and Arctic research. Nansen left the icebound Fram in 1895 and, with Hjalmar Johansen, traveled northward by dogsled and kayak in an unsuccessful effort to reach the North Pole. They set a new record for northward exploration by reaching 86 degrees 14' north latitude.
Much scientific work and the conquest of the North Pole in vanous ways has been accomplished in the 20th century. Vilhjalmur STEFANSSON explored many parts of the Arctic in the early part of the century, and Knud RAMUSSEN's 1921-24 studies of American Eskimo are recorded in his famous book, Across Artic America (1927). The Gjoa, under the command of Roald AMUNDSEN, became the first ship to successfully navigate the Northwest Passage; later, in the Maud (1918-20), Amundsen also navigated the Northeast Passage.
Many nations have expressed interest in the Arctic's resources, and the United States and Russia maintain a strong military presence in this strategic region. The Inuit (Eskimo People's) Circumpolar Conference, founded in 1980 following an initial (1977) meeting at Barrow, Alaska, has worked to formulate an Arctic policy on oil development, military maneuvers, and weapons testing that will preserve the Inuit way of life. U.S. concern for the preservation of the Arctic environment led to the passage of the controversial Alaska Lands Bill in 1980. In addition, the Arctic Research and Policy Act of 1984 was designed to promote scientific research and to coordinate policy in the Arctic region.
Robert F. Black
Bibliography: Fisher, David, Across the Top of the World (1992); Graf, Miller, Artic Journeys: A History of Exploration for the Northwest Passage (1921) Holland, Clive, ed., Arctic Exploration and Development (1993); Lynge, Finn, Arctic Wars, Animal Rights, Endangered Peoples (1992); Peary, R. E., The North Pole (1910; repr. 1968); Ray, G. C., and McCormick-Ray, M. G., Wildlife of the Polar Regions (1981); Vaughn, Richard, The Arctic in History (1994); Young, Oran, Arctic Politics (1992); Young, Steven B., To the Arctic; An Introduction to the Far Northern World (1989).
1996 Grolier Electronic Publishing. All Rights Reserved.