Arctic Circle

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World map showing the Arctic Circle in red.
Map of the Arctic with the Arctic Circle in blue.

The Arctic Circle is one of the five major circles of latitude that mark maps of the Earth. In 2012, it is the parallel of latitude that runs 66° 33′ 44″ (or 66.5622°) [1] north of the Equator.

The region north of this circle is known as the Arctic, and the zone just to the south is called the Northern Temperate Zone. The equivalent polar circle in the Southern Hemisphere is called the Antarctic Circle.

The Arctic Circle is the southernmost latitude in the Northern Hemisphere at which the sun can remain continuously above or below the horizon for 24 hours (at the June solstice and December solstice respectively). North of the Arctic Circle, the sun is above the horizon for 24 continuous hours at least once per year (and therefore visible at midnight) and below the horizon for 24 continuous hours at least once per year. On the Arctic Circle those events occur, in principle, exactly once per year, at the June and December solstices, respectively. However, in practice, because of atmospheric refraction and mirages, and because the sun appears as a disk and not a point, part of the midnight sun may be seen on the night of the northern summer solstice up to about 50 (90 km (56 mi)) south of the Arctic Circle; similarly, on the day of the northern winter solstice, part of the sun may be seen up to about 50′ north of the Arctic Circle. That is true at sea level; those limits increase with elevation above sea level, although in mountainous regions there is often no direct view of the true horizon.

The position of the Arctic Circle is not fixed. It directly depends on the Earth's axial tilt, which fluctuates within a margin of 2° over a 40,000-year period,[2] notably due to tidal forces resulting from the orbit of the Moon. The Arctic Circle is currently drifting northwards at a speed of about 15 m (49 ft) per year; see Circle of latitude for more information.


Geography[edit]

Relatively few people live north of the Arctic Circle due to the severe climate. Areas have been settled for thousands of years by indigenous peoples. Tens of thousands of years ago, waves of people migrated from eastern Siberia across the Bering Strait into North America and gradually eastward to settle. Much later, in the historic period, there has been migration into some Arctic areas by Europeans and other immigrants.

The three largest communities north of the Arctic Circle are situated in Russia and Norway: Murmansk (population 307,257), Norilsk (175,365), and Tromsø (71,295).

Rovaniemi (in Finland), which lies slightly south of the line, has a population of approximately 60,000, and is the largest settlement in the immediate vicinity of the Arctic Circle. Among the people of the Arctic, the Norwegians have the easiest climate, with most ports in North Norway remaining ice-free all the year as a result of the Gulf Stream. Tromsø (in Norway) has about 71,000 inhabitants and Bodø 49,000.

In contrast, the largest North American community north of the Circle, Sisimiut (Greenland), has approximately 5,000 inhabitants. Of the Canadian and United States Arctic communities, Barrow, Alaska is the largest settlement with circa 4,000 inhabitants.

The Arctic Circle passes through the Arctic Ocean, the Scandinavian Peninsula, North Asia, Northern America and Greenland. The land on the Arctic Circle is divided among eight countries: Norway, Sweden, Finland, Russia, the United States (Alaska), Canada, Denmark (Greenland), and Iceland (where it passes through the small offshore island of Grímsey).

The area north of the Arctic Circle is about 20,000,000 km2 (7,700,000 sq mi) and covers 4% of the Earth.[3]

Starting at the Prime Meridian and heading eastwards, the Arctic Circle passes through:

Co-ordinatesCountry, territory or seaNotes
66°34′N 000°00′E / 66.567°N 0.000°E / 66.567; 0.000 (Prime Meridian) Arctic OceanNorwegian Sea
66°34′N 12°48′E / 66.567°N 12.800°E / 66.567; 12.800 (Nordland County, Norway) NorwayNordland County
66°34′N 15°31′E / 66.567°N 15.517°E / 66.567; 15.517 (Norrbotten County, Sweden) SwedenNorrbotten County
66°34′N 23°51′E / 66.567°N 23.850°E / 66.567; 23.850 (Lapland Province, Finland) FinlandLapland Region
66°34′N 29°28′E / 66.567°N 29.467°E / 66.567; 29.467 (Karelia, Russia) RussiaRepublic of Karelia
Murmansk Oblast — from 66°34′N 31°36′E / 66.567°N 31.600°E / 66.567; 31.600 (Murmansk, Russia)
Republic of Karelia — from 66°34′N 32°37′E / 66.567°N 32.617°E / 66.567; 32.617 (Karelia, Russia)
Murmansk Oblast (Grand Island) — from 66°34′N 33°10′E / 66.567°N 33.167°E / 66.567; 33.167 (Murmansk, Russia)
66°34′N 33°25′E / 66.567°N 33.417°E / 66.567; 33.417 (Kandalaksha Gulf, White Sea)White SeaKandalaksha Gulf
66°34′N 34°28′E / 66.567°N 34.467°E / 66.567; 34.467 (Murmansk Oblast, Russia) RussiaMurmansk Oblast (Kola Peninsula) — for about 7 km (4.3 mi)
66°34′N 34°38′E / 66.567°N 34.633°E / 66.567; 34.633 (Kandalaksha Gulf, White Sea)White SeaKandalaksha Gulf
66°34′N 35°0′E / 66.567°N 35.000°E / 66.567; 35.000 (Murmansk Oblast, Kola Peninsula, Russia) RussiaMurmansk Oblast (Kola Peninsula)
66°34′N 40°42′E / 66.567°N 40.700°E / 66.567; 40.700 (White Sea)White Sea
66°34′N 44°23′E / 66.567°N 44.383°E / 66.567; 44.383 (Nenets Autonomous Okrug, Russia) RussiaNenets Autonomous Okrug
Komi Republic — from 66°34′N 50°51′E / 66.567°N 50.850°E / 66.567; 50.850 (Komi Republic, Russia)
Yamalo-Nenets Autonomous Okrug — from 66°34′N 63°48′E / 66.567°N 63.800°E / 66.567; 63.800 (Yamalo-Nenets Autonomous Okrug, Russia)
66°34′N 71°5′E / 66.567°N 71.083°E / 66.567; 71.083 (Gulf of Ob)Gulf of Ob
66°34′N 72°27′E / 66.567°N 72.450°E / 66.567; 72.450 (Yamalo-Nenets Autonomous Okrug, Russia) RussiaYamalo-Nenets Autonomous Okrug
Krasnoyarsk Krai — from 66°34′N 83°3′E / 66.567°N 83.050°E / 66.567; 83.050 (Krasnoyarsk Krai, Russia)
Sakha Republic — from 66°34′N 106°18′E / 66.567°N 106.300°E / 66.567; 106.300 (Sakha Republic, Russia)
Chukotka Autonomous Okrug — from 66°34′N 158°38′E / 66.567°N 158.633°E / 66.567; 158.633 (Chukotka Autonomous Okrug, Russia)
66°34′N 171°1′W / 66.567°N 171.017°W / 66.567; -171.017 (Chukchi Sea, Arctic Ocean)Arctic OceanChukchi Sea
66°34′N 164°38′W / 66.567°N 164.633°W / 66.567; -164.633 (Seward Peninsula, Alaska, United States) United StatesAlaska (Seward Peninsula)
66°34′N 163°44′W / 66.567°N 163.733°W / 66.567; -163.733 (Kotzebue Sound, Arctic Ocean)Arctic OceanKotzebue Sound
66°34′N 161°56′W / 66.567°N 161.933°W / 66.567; -161.933 (Alaska, United States) United StatesAlaska — passing through Selawik Lake
66°34′N 141°0′W / 66.567°N 141.000°W / 66.567; -141.000 (Yukon, Canada) CanadaYukon
Northwest Territories — from 66°34′N 133°36′W / 66.567°N 133.600°W / 66.567; -133.600 (Northwest Territories, Canada), passing through the Great Bear Lake
Nunavut — from 66°34′N 115°56′W / 66.567°N 115.933°W / 66.567; -115.933 (Nunavut, Canada)
66°34′N 82°59′W / 66.567°N 82.983°W / 66.567; -82.983 (Foxe Basin, Hudson Bay)Hudson BayFoxe Basin
66°34′N 73°25′W / 66.567°N 73.417°W / 66.567; -73.417 (Baffin Island, Nunavut, Canada) CanadaNunavut (Baffin Island), passing through Nettilling Lake
66°34′N 61°24′W / 66.567°N 61.400°W / 66.567; -61.400 (Davis Strait, Atlantic Ocean)Atlantic OceanDavis Strait
66°34′N 53°16′W / 66.567°N 53.267°W / 66.567; -53.267 (Greenland) Greenland
66°34′N 34°9′W / 66.567°N 34.150°W / 66.567; -34.150 (Denmark Strait, Atlantic Ocean)Atlantic OceanDenmark Strait
Greenland Sea — from 66°34′N 26°18′W / 66.567°N 26.300°W / 66.567; -26.300 (Greenland Sea)
66°34′N 18°1′W / 66.567°N 18.017°W / 66.567; -18.017 (Grímsey, Iceland) IcelandIsland of Grímsey
66°34′N 17°59′W / 66.567°N 17.983°W / 66.567; -17.983 (Greenland Sea, Atlantic Ocean)Atlantic OceanGreenland Sea
Norwegian Sea — from 66°34′N 12°32′W / 66.567°N 12.533°W / 66.567; -12.533 (Norwegian Sea)
A sign along the Dalton Highway marking the location of the Arctic Circle in Alaska.
Arctic Circle line in Rovaniemi, Finland
Aurora Borealis above Arctic Circle sign along the Dempster Highway in Yukon, Canada
A sign on the Vikingen island marking the Arctic Circle in Norway
The Arctic Circle on Grímsey in Iceland

See also[edit]

References[edit]

  1. ^ obliquity of the ecliptic (Eps Mean)
  2. ^ Arctic Circle
  3. ^ William M. Marsh; Martin M. Kaufman (2012). Physical Geography: Great Systems and Global Environments. Cambridge University Press. p. 24. ISBN 978-0-521-76428-5. 

External links[edit]