Map of the Arctic, with the Arctic Circle in blue and the 10°C July mean isotherm in red
The Arctic Circle marks the southernmost latitude at which, on the December solstice, the shortest day of the year in the northern hemisphere, the sun will not rise all day, and on the June solstice, the longest day of the year in the northern hemisphere, the sun will not set. These phenomena are referred to as polar night and midnight sun respectively, and the further north one progresses, the more pronounced these effects become. For example, in the Russian port city of Murmansk, three degrees above the Arctic Circle, the sun does not rise for 40 successive days in midwinter.[1][2][3]
The position of the Arctic Circle is not fixed and currently runs 66°33′49.3″ north of the Equator.[4] Its latitude depends on the Earth's axial tilt, which fluctuates within a margin of more than 2° over a 41,000-year period, owing to tidal forces resulting from the orbit of the Moon.[5] Consequently, the Arctic Circle is currently drifting northwards at a speed of about 14.5 m (48 ft) per year.
Relationship of Earth's axial tilt (ε) to the tropical and polar circles
The Arctic Circle is the southernmost latitude in the Northern Hemisphere at which the center of the sun can remain continuously above or below the horizon for twenty-four hours; as a result, at least once each year at any location within the Arctic Circle the center of the sun is visible at local midnight, and at least once the center is not visible at local noon.[8]
Directly on the Arctic Circle these events occur, in principle, exactly once per year: at the June and Decembersolstices, respectively. However, because of atmospheric refraction and mirages, and also 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 minutes (′) (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.
At night, bright aurora borealis are a fairly common sight in the Arctic Circle. The picture of the northern lights in Rovaniemi.
Human habitation
Cylindrical projection showing the Arctic Circle in red
The largest communities north of the Arctic Circle are situated in Russia, Norway, and Sweden: Murmansk (population 295,374) and Norilsk (178,018) in Russia; Tromsø (75,638) in Norway, Vorkuta (58,133) in Russia, Bodø (52,357), and Harstad (24,703) in Norway; and Kiruna, Sweden (22,841). Rovaniemi (62,667) in Finland is the largest settlement in the immediate vicinity of the Arctic Circle, lying 6 km (4 mi) south of the line. Salekhard (51,186) in Russia is the only city in the world located directly on the Arctic Circle.[9]
In contrast, the largest North American community north of the Arctic Circle, Sisimiut (Greenland), has approximately 5,000 inhabitants. In the United States, Utqiaġvik, Alaska is the largest settlement north of the Arctic Circle with about 4,000 inhabitants. The largest such community in Canada is Inuvik in The Northwest Territories, with 3,137 people living there.
The Arctic Circle is roughly 16,000 km (9,900 mi) in circumference.[10] The area north of the Circle is about 20,000,000 km2 (7,700,000 sq mi) and covers roughly 4% of Earth's surface.[11]
The climate north of the Arctic Circle is generally cold, but the coastal areas of Norway have a generally mild climate as a result of the Gulf Stream, which makes the ports of northern Norway and northwest Russia ice-free all year long. In the interior, summers can be quite warm, while winters are extremely cold. For example, summer temperatures in Norilsk, Russia will sometimes reach as high as 30 °C (86 °F), while the winter temperatures frequently fall below −50 °C (−58 °F).
Sites along the Arctic Circle
Starting at the prime meridian and heading eastwards, the Arctic Circle passes through:
^"40 days without the sun. How? Polar Night begins in Murmansk". Auroravillage.info. 3 December 2018. Retrieved 24 March 2022.
^Burn, Chris. The Polar Night(PDF). The Aurora Research Institute. Retrieved 28 September 2015.
^NB: This refers to the true geometric center which actually appears higher in the sky because of refraction by the atmosphere.
^"Obliquity of the Ecliptic (Eps Mean)". Neoprogrammics.com. Retrieved 13 May 2014.
^Berger, A. L. (1976). "Obliquity and Precession for the Last 5000000 Years". Astronomy and Astrophysics. 51 (1): 127–135. Bibcode:1976A&A....51..127B.
^Liddell, Henry; Scott, Robert. "Arktos". A Greek–English Lexicon. Perseus Digital Library.
^Burn, Chris. The Polar Night(PDF). The Aurora Research Institute. Retrieved 28 September 2015.
^Всеволод Липатов (26 April 2011). "Город на Полярном круге". ToGeo.ru (in Russian).
^Nuttall, Mark (2004). Encyclopedia of the Arctic Volumes 1, 2 and 3. Routledge. p. 115. ISBN978-1579584368.
^Marsh, William M.; Kaufman, Martin M. (2012). Physical Geography: Great Systems and Global Environments. Cambridge University Press. p. 24. ISBN978-0-521-76428-5.
External links
Wikimedia Commons has media related to Arctic Circle.
Look up arctic circle in Wiktionary, the free dictionary.
Terra Incognita: Exploration of the Canadian Arctic—Historical essay about early expeditions to the Canadian Arctic, illustrated with maps, photographs and drawings
arctic, circle, this, article, about, five, major, circles, latitude, other, uses, disambiguation, polar, circles, most, northerly, five, major, circles, latitude, shown, maps, earth, southern, equivalent, antarctic, circle, arctic, with, blue, july, mean, iso. This article is about one of the five major circles of latitude For other uses see Arctic Circle disambiguation The Arctic Circle is one of the two polar circles and the most northerly of the five major circles of latitude as shown on maps of Earth Its southern equivalent is the Antarctic Circle Map of the Arctic with the Arctic Circle in blue and the 10 C July mean isotherm in red The Arctic Circle marks the southernmost latitude at which on the December solstice the shortest day of the year in the northern hemisphere the sun will not rise all day and on the June solstice the longest day of the year in the northern hemisphere the sun will not set These phenomena are referred to as polar night and midnight sun respectively and the further north one progresses the more pronounced these effects become For example in the Russian port city of Murmansk three degrees above the Arctic Circle the sun does not rise for 40 successive days in midwinter 1 2 3 The position of the Arctic Circle is not fixed and currently runs 66 33 49 3 north of the Equator 4 Its latitude depends on the Earth s axial tilt which fluctuates within a margin of more than 2 over a 41 000 year period owing to tidal forces resulting from the orbit of the Moon 5 Consequently the Arctic Circle is currently drifting northwards at a speed of about 14 5 m 48 ft per year Contents 1 Etymology 2 Midnight sun and polar night 3 Human habitation 4 Geography 4 1 Climate 4 2 Sites along the Arctic Circle 5 Gallery 6 See also 7 References 8 External linksEtymology EditThe word arctic comes from the Greek word ἀrktikos arktikos near the Bear northern 6 and that from the word ἄrktos arktos bear 7 Midnight sun and polar night EditFurther information Midnight sun and Polar night Relationship of Earth s axial tilt e to the tropical and polar circles The Arctic Circle is the southernmost latitude in the Northern Hemisphere at which the center of the sun can remain continuously above or below the horizon for twenty four hours as a result at least once each year at any location within the Arctic Circle the center of the sun is visible at local midnight and at least once the center is not visible at local noon 8 Directly on the Arctic Circle these events occur in principle exactly once per year at the June and December solstices respectively However because of atmospheric refraction and mirages and also 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 minutes 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 At night bright aurora borealis are a fairly common sight in the Arctic Circle The picture of the northern lights in Rovaniemi Human habitation Edit Cylindrical projection showing the Arctic Circle in red Further information Circumpolar peoples The largest communities north of the Arctic Circle are situated in Russia Norway and Sweden Murmansk population 295 374 and Norilsk 178 018 in Russia Tromso 75 638 in Norway Vorkuta 58 133 in Russia Bodo 52 357 and Harstad 24 703 in Norway and Kiruna Sweden 22 841 Rovaniemi 62 667 in Finland is the largest settlement in the immediate vicinity of the Arctic Circle lying 6 km 4 mi south of the line Salekhard 51 186 in Russia is the only city in the world located directly on the Arctic Circle 9 In contrast the largest North American community north of the Arctic Circle Sisimiut Greenland has approximately 5 000 inhabitants In the United States Utqiaġvik Alaska is the largest settlement north of the Arctic Circle with about 4 000 inhabitants The largest such community in Canada is Inuvik in The Northwest Territories with 3 137 people living there Geography EditMap all coordinates using OpenStreetMap Download coordinates as KMLThe Arctic Circle is roughly 16 000 km 9 900 mi in circumference 10 The area north of the Circle is about 20 000 000 km2 7 700 000 sq mi and covers roughly 4 of Earth s surface 11 The Arctic Circle passes through the Arctic Ocean the Scandinavian Peninsula North Asia Northern America and Greenland The land within the Arctic Circle is divided among eight countries Norway Sweden Finland Russia the United States Alaska Canada Yukon Northwest Territories and Nunavut Denmark Greenland and Iceland where it passes through the small offshore island of Grimsey Climate Edit Further information Climate of the Arctic The climate north of the Arctic Circle is generally cold but the coastal areas of Norway have a generally mild climate as a result of the Gulf Stream which makes the ports of northern Norway and northwest Russia ice free all year long In the interior summers can be quite warm while winters are extremely cold For example summer temperatures in Norilsk Russia will sometimes reach as high as 30 C 86 F while the winter temperatures frequently fall below 50 C 58 F Sites along the Arctic Circle Edit Starting at the prime meridian and heading eastwards the Arctic Circle passes through Co ordinates Country territory or ocean Notes66 34 N 0 0 E 66 567 N 0 000 E 66 567 0 000 Prime Meridian Atlantic Ocean Norwegian Sea66 34 N 12 3 E 66 567 N 12 050 E 66 567 12 050 Nordland County Norway Norway Islands and skerries of Traena Nordland County66 34 N 12 18 E 66 567 N 12 300 E 66 567 12 300 Norwegian Sea Atlantic Ocean Traenfjorden Norwegian Sea66 34 N 12 29 E 66 567 N 12 483 E 66 567 12 483 Nordland County Norway Norway Islands and skerries of Nesoya Nordland County66 34 N 12 41 E 66 567 N 12 683 E 66 567 12 683 Norwegian Sea Atlantic Ocean Nesoyfjorden Norwegian Sea66 34 N 12 49 E 66 567 N 12 817 E 66 567 12 817 Nordland County Norway Norway Islands and skerries of Storseloya Nordland County66 34 N 12 52 E 66 567 N 12 867 E 66 567 12 867 Norwegian Sea Atlantic Ocean Kvaroyfjorden Norwegian Sea66 34 N 12 57 E 66 567 N 12 950 E 66 567 12 950 Nordland County Norway Norway Islands and skerries of Rangsundoya Nordland County including Vikingen Island66 34 N 13 3 E 66 567 N 13 050 E 66 567 13 050 Norwegian Sea Atlantic Ocean Vaerangfjorden Norwegian Sea66 34 N 13 12 E 66 567 N 13 200 E 66 567 13 200 Nordland County Norway Norway Nordland County66 34 N 15 33 E 66 567 N 15 550 E 66 567 15 550 Norrbotten County Sweden Sweden Norrbotten County Provinces of Lapland and Norrbotten 66 34 N 23 51 E 66 567 N 23 850 E 66 567 23 850 Lapland Province Finland Finland Lapland Region crosses Rovaniemi Airport66 34 N 29 28 E 66 567 N 29 467 E 66 567 29 467 Karelia Russia Russia Republic of Karelia66 34 N 31 36 E 66 567 N 31 600 E 66 567 31 600 Murmansk Russia Murmansk Oblast66 34 N 32 37 E 66 567 N 32 617 E 66 567 32 617 Karelia Russia Republic of Karelia66 34 N 33 10 E 66 567 N 33 167 E 66 567 33 167 Murmansk Russia Grand Island Murmansk Oblast66 34 N 33 25 E 66 567 N 33 417 E 66 567 33 417 Kandalaksha Gulf White Sea Arctic Ocean Kandalaksha Gulf White Sea Barents Sea66 34 N 34 28 E 66 567 N 34 467 E 66 567 34 467 Murmansk Oblast Russia Russia Kola Peninsula Murmansk Oblast 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 Arctic Ocean Kandalaksha Gulf White Sea Barents Sea66 34 N 35 0 E 66 567 N 35 000 E 66 567 35 000 Murmansk Oblast Kola Peninsula Russia Russia Kola Peninsula Murmansk Oblast66 34 N 40 42 E 66 567 N 40 700 E 66 567 40 700 White Sea Arctic Ocean White Sea Barents Sea66 34 N 44 23 E 66 567 N 44 383 E 66 567 44 383 Nenets Autonomous Okrug Russia Russia Nenets Autonomous Okrug66 34 N 50 51 E 66 567 N 50 850 E 66 567 50 850 Komi Republic Russia Komi Republic66 34 N 63 48 E 66 567 N 63 800 E 66 567 63 800 Yamalo Nenets Autonomous Okrug Russia Yamalo Nenets Autonomous Okrug66 34 N 71 5 E 66 567 N 71 083 E 66 567 71 083 Gulf of Ob Arctic Ocean Gulf of Ob Kara Sea66 34 N 72 27 E 66 567 N 72 450 E 66 567 72 450 Yamalo Nenets Autonomous Okrug Russia Russia Yamalo Nenets Autonomous Okrug66 34 N 83 3 E 66 567 N 83 050 E 66 567 83 050 Krasnoyarsk Krai Russia Krasnoyarsk Krai66 34 N 106 18 E 66 567 N 106 300 E 66 567 106 300 Sakha Republic Russia Yukaghir Highlands Sakha Republic66 34 N 158 38 E 66 567 N 158 633 E 66 567 158 633 Chukotka Autonomous Okrug Russia Anadyr Highlands and Chukotka Mountains Chukotka Autonomous Okrug66 34 N 171 1 W 66 567 N 171 017 W 66 567 171 017 Chukchi Sea Arctic Ocean Arctic Ocean Chukchi Sea66 34 N 164 38 W 66 567 N 164 633 W 66 567 164 633 Seward Peninsula Alaska United States United States Seward Peninsula Alaska66 34 N 163 44 W 66 567 N 163 733 W 66 567 163 733 Kotzebue Sound Arctic Ocean Arctic Ocean Kotzebue Sound Chukchi Sea66 34 N 161 56 W 66 567 N 161 933 W 66 567 161 933 Alaska United States United States Alaska passing through Selawik Lake66 34 N 141 0 W 66 567 N 141 000 W 66 567 141 000 Yukon Canada Canada Yukon66 34 N 133 36 W 66 567 N 133 600 W 66 567 133 600 Northwest Territories Canada Northwest Territories passing through Great Bear Lake66 34 N 115 56 W 66 567 N 115 933 W 66 567 115 933 Nunavut Canada Nunavut66 34 N 82 59 W 66 567 N 82 983 W 66 567 82 983 Foxe Basin Hudson Bay Arctic Ocean Foxe Basin66 34 N 73 25 W 66 567 N 73 417 W 66 567 73 417 Baffin Island Nunavut Canada Canada Nunavut Baffin Island passing through Nettilling Lake and Auyuittuq National Park sign location 66 34 N 61 24 W 66 567 N 61 400 W 66 567 61 400 Davis Strait Atlantic Ocean Atlantic Ocean Davis Strait66 34 N 53 16 W 66 567 N 53 267 W 66 567 53 267 Greenland Greenland passing through Kangerlussuaq Fjord and Schweizerland66 34 N 34 9 W 66 567 N 34 150 W 66 567 34 150 Denmark Strait Atlantic Ocean Atlantic Ocean Denmark Strait66 34 N 26 18 W 66 567 N 26 300 W 66 567 26 300 Greenland Sea Greenland Sea66 34 N 18 1 W 66 567 N 18 017 W 66 567 18 017 Grimsey Iceland Iceland Island of Grimsey66 34 N 17 59 W 66 567 N 17 983 W 66 567 17 983 Greenland Sea Atlantic Ocean Atlantic Ocean Greenland Sea66 34 N 12 32 W 66 567 N 12 533 W 66 567 12 533 Norwegian Sea Norwegian SeaGallery Edit Polcirkeln portal in Gallivare Sweden Arctic Circle line in Rovaniemi Finland c 1865 Arctic Circle monument in Salekhard Russia A sign along the Dalton Highway marking the location of the Arctic Circle in Alaska Aurora Borealis above Arctic Circle sign along the Dempster Highway in Yukon at 66 33 55 N 136 18 26 W 66 56528 N 136 30722 W 66 56528 136 30722 Arctic Circle sign Northern Polar Circle Globe on Vikingen island marking the Arctic Circle in Norway Arctic Circle sign by the Inland Line railway Sweden The white borderline of the Arctic Circle at the Santa Claus Village in Rovaniemi Finland Arctic Circle sign in the Republic of Karelia Russia Arctic Circle sign by the Yamalo Nenets Autonomous Okrug Russia A sign in the Sakha Republic Yakutia Russia Arctic Circle marker on island of Grimsey in IcelandSee also Edit60th parallel north Antarctic Circle Arctic cooperation and politics Arctic haze Circumpolar star Equator Scott Polar Research Institute Territorial claims in the Arctic Tropic of Cancer Tropic of CapricornReferences Edit 40 days without the sun How Polar Night begins in Murmansk Auroravillage info 3 December 2018 Retrieved 24 March 2022 Burn Chris The Polar Night PDF The Aurora Research Institute Retrieved 28 September 2015 NB This refers to the true geometric center which actually appears higher in the sky because of refraction by the atmosphere Obliquity of the Ecliptic Eps Mean Neoprogrammics com Retrieved 13 May 2014 Berger A L 1976 Obliquity and Precession for the Last 5000000 Years Astronomy and Astrophysics 51 1 127 135 Bibcode 1976A amp A 51 127B Liddell Henry Scott Robert Arktikos A Greek English Lexicon Perseus Digital Library Liddell Henry Scott Robert Arktos A Greek English Lexicon Perseus Digital Library Burn Chris The Polar Night PDF The Aurora Research Institute Retrieved 28 September 2015 Vsevolod Lipatov 26 April 2011 Gorod na Polyarnom kruge ToGeo ru in Russian Nuttall Mark 2004 Encyclopedia of the Arctic Volumes 1 2 and 3 Routledge p 115 ISBN 978 1579584368 Marsh William M Kaufman Martin M 2012 Physical Geography Great Systems and Global Environments Cambridge University Press p 24 ISBN 978 0 521 76428 5 External links Edit Wikimedia Commons has media related to Arctic Circle Look up arctic circle in Wiktionary the free dictionary Terra Incognita Exploration of the Canadian Arctic Historical essay about early expeditions to the Canadian Arctic illustrated with maps photographs and drawings Temporal Epoch Calculations c 2006 by James Q Jacobs Download Epoch v2009 xls modify D4 Useful constants See Obliquity of the ecliptic Retrieved from https en wikipedia org w index php title Arctic Circle amp oldid 1128443445, wikipedia, wiki, book, books, library,
