| Dictionary, Encyclopedia and Thesaurus - The Free Dictionary 1,726,309,308 visitors served. |
|
Dictionary/ thesaurus | Medical dictionary | Legal dictionary | Financial dictionary | Acronyms | Idioms | Encyclopedia | Wikipedia encyclopedia | ? |
Arctic, the |
Also found in: Hutchinson | 0.02 sec. |
|
Arctic, the northernmost area of the earth, centered on the North Pole North Pole, northern end of the earth's axis, lat. 90°N. It is distinguished from the north magnetic pole . U.S. explorer Robert E. Peary is traditionally credited as being the first to reach (1909) the North Pole. In 1926, Richard E. ..... Click the link for more information. . The arctic regions are not coextensive with the area enclosed by the Arctic Circle Arctic Circle, imaginary circle on the surface of the earth at 66 1-2°N latitude, i.e., 23 1-2° south of the North Pole. It marks the northernmost point at which the sun can be seen at the winter solstice (about Dec. ..... Click the link for more information. (lat. 66°30'N) but are usually defined by the irregular and shifting 50°F; (10°C;) July isotherm that closely corresponds to the northern limit of tree growth and that varies both N and S of the Arctic Circle. The regions therefore include the Arctic Ocean Arctic Ocean, the smallest ocean, c.5,400,000 sq mi (13,986,000 sq km), located entirely within the Arctic Circle and occupying the region around the North Pole. ..... Click the link for more information. ; the northern reaches of Canada, Alaska, Russia, Norway, and the Atlantic Ocean; Svalbard Svalbard (sväl`bärd), archipelago (23,958 sq mi/62,051 sq km), island group (2005 est. pop. ..... Click the link for more information. ; most of Iceland; Greenland Greenland, Green. Kalaallit Nunaat, Dan. Grønland, the largest island in the world (2005 est. pop. 56,000), 836,109 sq mi (2,166,086 sq km), self-governing overseas administrative division of Denmark, lying largely within the Arctic Circle. ..... Click the link for more information. ; and the Bering Sea. GeologyIn the center of the Arctic is a large basin occupied by the Arctic Ocean. The basin is nearly surrounded by the ancient continental shields of North America, Europe, and Asia, with the geologically more recent lowland plains, low plateaus, and mountain chains between them. Surface features vary from low coastal plains (swampy in summer, especially at the mouths of such rivers as the Mackenzie, Lena, Yenisei, and Ob) to high ice plateaus and glaciated mountains. Tundras tundra (tŭn`drə), treeless plains of N North America and N Eurasia, lying principally along the Arctic Circle, on the coasts and ClimateThe climate of the Arctic, classified as polar, is characterized by long, cold winters and short, cool summers. Polar climate may be further subdivided into tundra climate (the warmest month of which has an average temperature below 50°F;/10°C; but above 32°F;/0°C;) and ice cap climate (all months average below 32°F;/0°C;, and there is a permanent snow cover). Precipitation, almost entirely in the form of snow, is very low, with the annual average precipitation for the regions less than 20 in. (51 cm). Persistent winds whip up fallen snow to create the illusion of constant snowfall. The climate is moderated by oceanic influences, with regions abutting the Atlantic and Pacific oceans having generally warmer temperatures and heavier snowfalls than the colder and drier interior areas. However, except along its fringe, the Arctic Ocean remains frozen throughout the year. Great seasonal changes in the length of days and nights are experienced N of the Arctic Circle, with variations that range from 24 hours of constant daylight ("midnight sun") or darkness at the Arctic Circle to six months of daylight or darkness at the North Pole. However, because of the low angle of the sun above the horizon, insolation is minimal throughout the regions, even during the prolonged daylight period. A famous occurrence in the arctic night sky is the aurora borealis aurora borealis (bôr'ēăl`ĭs) and aurora australis Flora and FaunaVegetation in the Arctic, limited to regions having a tundra climate, flourishes during the short spring and summer seasons. The tundra's restrictive environment for plant life increases northward, with dwarf trees giving way to grasses (mainly mosses, lichen, sedges, and some flowering plants), the ground coverage of which becomes widely scattered toward the permanent snow line. There are about 20 species of land animals in the Arctic, including the squirrel, wolf, fox, moose, caribou, reindeer, polar bear, musk ox, and about six species of aquatic mammals such as the walrus, seal, and whale. Most of the species are year-round inhabitants of the Arctic, migrating to the southern margins as winter approaches. Although generally of large numbers, some of the species, especially the fur-bearing ones, are in danger of extinction. A variety of fish is found in arctic seas, rivers, and lakes. The Arctic's bird population increases tremendously each spring with the arrival of migratory birds (see migration of animals migration of animals, movements of animals in large numbers from one place to another. In modern usage the term is usually restricted to regular, periodic movements of populations away from and back to their place of origin. Natural ResourcesIn parts of the Arctic are found a variety of natural resources, but many known reserves are not exploited because of their inaccessibility. The arctic region of Russia, the most developed of all the arctic regions, is a vast storehouse of mineral wealth, including deposits of nickel, copper, coal, gold, uranium, tungsten, and diamonds. The North American Arctic yields uranium, copper, nickel, iron, natural gas, and oil. The arctic region of Europe (including W Russia) benefits from good overland links with southern areas and ship routes that are open throughout the year. The arctic regions of Asian Russia and North America depend on isolated overland routes, summertime ship routes, and air transportation. Transportation of oil by pipeline from arctic Alaska was highly controversial in the early 1970s, with strong opposition from environmentalists. Because of the extreme conditions of the Arctic, the delicate balance of nature, and the slowness of natural repairs, the protection and preservation of the Arctic have been major goals of conservationists, who fear irreparable damage to the natural environment from local temperature increases, the widespread use of machinery, the interference with wildlife migration, and oil spills. PeopleThe Arctic is one of the world's most sparsely populated areas. Its inhabitants, basically of Mongolic stock, are thought to be descendants of a people who migrated northward from central Asia after the ice age and subsequently spread W into Europe and E into North America. The chief groups are now the Lapps of Europe; the Samoyedes Samoyedes or Samoyeds (both: săm`əyĕdz') Because of their common background and the general lack of contact with other peoples, arctic peoples have strikingly similar physical characteristics and cultures, especially in such things as clothing, tools, techniques, and social organization. The arctic peoples, once totally nomadic, are now largely sedentary or seminomadic. Hunting, fishing, reindeer herding, and indigenous arts and crafts are the chief activities. The arctic peoples are slowly being incorporated into the society of the country in which they are located. With the Arctic's increased economic and political role in world affairs, the regions have experienced an influx of personnel charged with building and maintaining such things as roads, mineral extraction sites, weather stations, and military installations. History of ExplorationMany parts of the Arctic were already settled by the Eskimos and other peoples of Mongolic stock when the first European explorers, the Norsemen or Vikings Vikings, Scandinavian warriors who raided the coasts of Europe and the British Isles from the 9th cent. to the 11th cent. During the Neolithic period the Scandinavians had lived in small autonomous communities as farmers, fishermen, and hunters. After 1815, British naval officers—including John Franklin Franklin, Sir John, 1786–1847, British explorer in N Canada whose disappearance caused a widespread search of the Arctic. Entering the navy in 1801, he fought in the battle of Trafalgar. Otto Sverdrup Sverdrup, Otto (ô`tō svĕr`dr Air exploration of the regions began with the tragic balloon attempt of S. A. Andrée Andrée, Salomon August (sä`l In 1937 and 1938 many field expeditions were sent out by British, Danish, Norwegian, Soviet, Canadian, and American groups to learn more about the Arctic. The Soviet group under Ivan Papinin wintered on an ice floe near the North Pole and drifted with the current for 274 days. Valuable hydrological, meteorological, and magnetic observations were made; by the time they were taken off the floe, the group had drifted 19° of latitude and 58° of longitude. Arctic drift was further explored (1937–40) by the Soviet icebreaker Sedov. Before World War II the USSR had established many meteorological and radio stations in the Arctic. Soviet activity in practical exploitation of resources also pointed the way to the development of arctic regions. Between 1940 and 1942 the Canadian vessel St. Roch made the first west-east journey through the Northwest Passage. In World War II, interest in transporting supplies gave rise to considerable study of arctic conditions. After the war interest in the Arctic was keen. The Canadian army in 1946 undertook a project that had as one of its objects the testing of new machines (notably the snowmobile) for use in developing the Arctic. There was also a strong impulse to develop Alaska and N Canada, but no consolidated effort, like that of the Soviets, to take the natives into partnership for a full-scale development of the regions. Since 1954 the United States and Russia have established a number of drifting observation stations on ice floes for the purpose of intensified scientific observations. In 1955, as part of joint U.S.-Canadian defense, construction was begun on a c.3,000-mi (4,830-km) radar network (the Distant Early Warning line, commonly called the DEW line) stretching from Alaska to Greenland. As older radar stations were replaced and new ones built, a more sophisticated surveillance system developed. In 1993 the system, now stretching from NW Alaska to the coast of Newfoundland, was renamed the North Warning System. With the continuing development of northern regions (e.g., Alaska, N Canada, and Russia), the Arctic has assumed greater importance in the world. During the International Geophysical Year (1957–58) more than 300 arctic stations were established by the northern countries interested in the arctic regions. Atomic-powered submarines have been used for penetrating the Arctic. In 1958 the Nautilus, a U.S. navy atomic-powered submarine, became the first ship to cross the North Pole undersea. Two years later the Skate set out on a similar voyage and became the first to surface at the Pole. In 1977 the Soviet nuclear icebreaker Arktika reached the North Pole, the first surface ship to do so. In the 1960s the Arctic became the scene of an intense search for mineral and power resources. The discovery of oil on the Alaska North Slope (1968) and on Canada's Ellesmere Island (1972) led to a great effort to find new oil fields along the edges of the continents. In the summer of 1969 the SS Manhattan, a specially designed oil tanker with ice breaker and oceanographic research vessel features, successfully sailed from Philadelphia to Alaska by way of the Northwest Passage in the first attempt to bring commercial shipping into the region. In 1971 the Arctic Ice Dynamics Joint Experiment (AIDJEX) began an international effort to study over a period of years arctic pack ice and its effect on world climate. In 1986 a seasonal "hole" in the ozone layer above the Arctic was discovered, showing some similarities to a larger depletion of ozone over the southern polar region; depletion of the ozone layer ozone layer or ozonosphere, region of the stratosphere containing relatively high concentrations of ozone , located at altitudes of 12–30 mi (19–48 km) above the earth's surface. BibliographyClassic narratives of arctic exploration include F. Nansen, In Northern Mists (tr. 1911); R. E. Amundsen, The North West Passage (tr., 2 vol., 1908); R. E. Peary, The North Pole (1910, repr. 1969); V. Stefansson, My Life with the Eskimo (1913) and The Friendly Arctic (1921). For history and geography, see L. P. Kirwan, A History of Polar Exploration (1960); R. Thorén, Picture Atlas of the Arctic (1969); L. H. Neatby, Conquest of the Last Frontier (1966) and Discovery in Russian and Siberian Waters (1973); L. Rey et al., ed., Unveiling the Arctic (1984); F. Bruemmer and W. E. Taylor, The Arctic World (1987); R. McCormick, Voyages of Discovery in the Antarctic and Arctic Seas (1990); F. Fleming, Barrow's Boys (1998) and Ninety Degrees North: The Quest for the North Pole (2002); C. Officer and J. Page, A Fabulous Kingdom: The Exploration of the Arctic (2001). How to thank TFD for its existence? Tell a friend about us, add a link to this page, add the site to iGoogle, or visit webmaster's page for free fun content. |
|
| ? Mentioned in | ? References in periodicals archive | ||
|---|---|---|---|
| Emerging from the work of hundreds of scientists and incorporating indigenous knowledge about conditions in the Arctic, the ACIA paints a sobering picture of the effect of present and expected global warming on Arctic peoples and ecosystems. The plan is to collect data that can help scientists understand the geology of the Arctic, the effects of pollution on Arctic ecosystems, and the ways the Arctic affects the rest of the world. As they moved through the Arctic, the Russian teams launched balloons carrying meteorological instruments. |
| Encyclopedia |
| Free Tools: |
For surfers:
Free toolbar & extensions |
Word of the Day |
Help
For webmasters: Free content | Linking | Lookup box | Double-click lookup | Partner with us |
|---|