North Pole
The North Pole, also known as the Geographic North Pole or Terrestrial North Pole, is (subject to the caveats explained below) defined as the point in the Northern Hemisphere where the Earth's axis of rotationmeets its surface. It should not be confused with the North Magnetic Pole.
The North Pole is the northernmost point on the Earth, lying diametrically opposite the South Pole. It defines geodetic latitude 90° North, as well as the direction of true north. At the North Pole all directions point south; all lines of longitude converge there, so its longitude can be defined as any degree value. Along tight latitude circles, counterclockwise is east and clockwise is west.
While the South Pole lies on a continental land mass, the North Pole is located in the middle of the Arctic Ocean amid waters that are almost permanently covered with constantly shifting sea ice. This makes it impractical to construct a permanent station at the North Pole (unlike the South Pole). However, the Soviet Union, and later Russia, constructed a number of manned drifting stations on a generally annual basis since 1937, some of which have passed over or very close to the Pole. Since 2002, the Russians have also annually established a base, Barneo, close to the Pole. This operates for a few weeks during early spring. Studies in the 2000s predicted that the North Pole may become seasonally ice-free because of Arctic ice shrinkage, with timescales varying from 2016[1][2] to the late 21st century or later.
The sea depth at the North Pole has been measured at 4,261 m (13,980 ft) by the Russian Mir submersible in 2007[3] and at 4,087 m (13,410 ft) by USS Nautilus in 1958.[4][5] The nearest land is usually said to beKaffeklubben Island, off the northern coast of Greenland about 700 km (430 mi) away, though some perhaps non-permanent gravel banks lie slightly closer. The nearest permanently inhabited place is Alert in theQikiqtaaluk Region, Nunavut, Canada, which is located 817 km (508 mi) from the Pole.
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Precise definition[edit]
See also: Polar motion
The Earth's axis of rotation – and hence the position of the North Pole – was commonly believed to be fixed (relative to the surface of the Earth) until, in the 18th century, the mathematician Leonhard Euler predicted that the axis might "wobble" slightly. Around the beginning of the 20th century astronomers noticed a small apparent "variation of latitude," as determined for a fixed point on Earth from the observation of stars. Part of this variation could be attributed to a wandering of the Pole across the Earth's surface, by a range of a few metres. The wandering has several periodic components and an irregular component. The component with a period of about 435 days is identified with the 8 month wandering predicted by Euler and is now called the Chandler wobble after its discoverer. The exact point of intersection of the Earth's axis and the Earth's surface, at any given moment, is called the "instantaneous pole", but because of the "wobble" this cannot be used as a definition of a fixed North Pole (or South Pole) when metre-scale precision is required.
It is desirable to tie the system of Earth coordinates (latitude, longitude, and elevations or orography) to fixed landforms. Of course, given plate tectonics and isostasy, there is no system in which all geographic features are fixed. Yet the International Earth Rotation and Reference Systems Service and the International Astronomical Union have defined a framework called the International Terrestrial Reference System.
Exploration[edit]
Pre-1900[edit]
As early as the 16th century, many eminent people correctly believed that the North Pole was in a sea, which in the 19th century was called the Polynya or Open Polar Sea.[6] It was therefore hoped that passage could be found through ice floes at favorable times of the year. Several expeditions set out to find the way, generally with whaling ships, already commonly used in the cold northern latitudes.
One of the earliest expeditions to set out with the explicit intention of reaching the North Pole was that of British naval officer William Edward Parry, who in 1827 reached latitude 82°45′ North. In 1871 the Polaris expedition, a US attempt on the Pole led by Charles Francis Hall, ended in disaster. Another British Royal Navy attempt on the pole, part of the British Arctic Expedition, by Commander Albert H. Markham reached a then-record 83°20'26" North in May 1876 before turning back. An 1879–1881 expedition commanded by US naval officer George W. DeLong ended tragically when their ship, the USS Jeanette, was crushed by ice. Over half the crew, including DeLong, were lost.
In April 1895 the Norwegian explorers Fridtjof Nansen and Hjalmar Johansen struck out for the Pole on skis after leaving Nansen's icebound ship Fram. The pair reached latitude 86°14′ North before they abandoned the attempt and turned southwards, eventually reaching Franz Josef Land.
In 1897 Swedish engineer Salomon August Andrée and two companions tried to reach the North Pole in the hydrogen balloon Örnen ("Eagle"), but came down 300 km (190 mi) north of Kvitøya, the northeasternmost part of the Svalbard archipelago. They trekked to Kvitøya but died there three months later. In 1930 the remains of this expedition were found by the Norwegian Bratvaag Expedition.
The Italian explorer Luigi Amedeo, Duke of the Abruzzi and Captain Umberto Cagni of the Italian Royal Navy (Regia Marina) sailed the converted whaler Stella Polare ("Pole Star") from Norway in 1899. On 11 March 1900 Cagni led a party over the ice and reached latitude 86° 34’ on 25 April, setting a new record by beating Nansen's result of 1895 by 35 to 40 km (22 to 25 mi). Cagni barely managed to return to the camp, remaining there until 23 June. On 16 August the Stella Polare left Rudolf Island heading south and the expedition returned to Norway.
1900–1940[edit]
The US explorer Frederick Cook claimed to have reached the North Pole on 21 April 1908 with two Inuit men, Ahwelah and Etukishook, but he was unable to produce convincing proof and his claim is not widely accepted.[8]
The conquest of the North Pole was for many years credited to US Navy engineer Robert Peary, who claimed to have reached the Pole on 6 April 1909, accompanied by Matthew Hensonand four Inuit men, Ootah, Seeglo, Egingwah, and Ooqueah. However, Peary's claim remains highly disputed and controversial. Those who accompanied Peary on the final stage of the journey were not trained in navigation, and thus could not independently confirm his navigational work, which some claim to have been particularly sloppy as he approached the Pole.
The distances and speeds that Peary claimed to have achieved once the last support party turned back seem incredible to many people, almost three times that which he had accomplished up to that point. Peary's account of a journey to the Pole and back while traveling along the direct line – the only strategy that is consistent with the time constraints that he was facing – is contradicted by Henson's account of tortuous detours to avoid pressure ridges and open leads.
The British explorer Wally Herbert, initially a supporter of Peary, researched Peary's records in 1989 and found that there were significant discrepancies in the explorer's navigational records. He concluded that Peary had not reached the Pole.[9] Support for Peary came again in 2005, however, when British explorer Tom Avery and four companions recreated the outward portion of Peary's journey with replica wooden sleds and Canadian Eskimo Dog teams, reaching the North Pole in 36 days, 22 hours – nearly five hours faster than Peary. However, Avery's fastest 5-day march was 90 nautical miles, significantly short of the 135 claimed by Peary. Avery writes on his web site that "The admiration and respect which I hold for Robert Peary, Matthew Henson and the four Inuit men who ventured North in 1909, has grown enormously since we set out from Cape Columbia. Having now seen for myself how he travelled across the pack ice, I am more convinced than ever that Peary did indeed discover the North Pole."[10]
Another rejection of Peary's claim arrived in 2009, when E. Myles Standish of the California Institute of Technology, an experienced referee of scientific claims, reported numerous allegedlacunae and inconsistencies.[11][unreliable source?]
The first claimed flight over the Pole was made on 9 May 1926 by US naval officer Richard E. Byrd and pilot Floyd Bennett in a Fokker tri-motor aircraft. Although verified at the time by a committee of the National Geographic Society, this claim has since been undermined[12] by the 1996 revelation that Byrd's long-hidden diary's solar sextant data (which the NGS never checked) consistently contradict his June 1926 report's parallel data by over 100 mi (160 km).[13] The secret report's alleged en-route solar sextant data were inadvertently so impossibly overprecise that he excised all these alleged raw solar observations out of the version of the report finally sent to geographical societies five months later (while the original version was hidden for 70 years), a realization first published in 2000 by the University of Cambridge after scrupulous refereeing.[14]
According to Standish, "Anyone who is acquainted with the facts and has any amount of logical reasoning can not avoid the conclusion that neither Cook, nor Peary, nor Byrd reached the North Pole; and they all knew it."[11][unreliable source?]
The first consistent, verified, and scientifically convincing attainment of the Pole was on 12 May 1926, by Norwegian explorer Roald Amundsen and his US sponsor Lincoln Ellsworth from the airship Norge.[15] Norge, though Norwegian-owned, was designed and piloted by the Italian Umberto Nobile. The flight started from Svalbard in Norway, and crossed the Arctic Ocean to Alaska. Nobile, with several scientists and crew from the Norge, overflew the Pole a second time on 24 May 1928, in the airship Italia. The Italia crashed on its return from the Pole, with the loss of half the crew.
In May 1937 the world's first North Pole ice station, North Pole-1, was established by Soviet scientists by air 20 kilometres (13 mi) from the North Pole. The expedition members: oceanographer Pyotr Shirshov, meteorologistYevgeny Fyodorov, radio operator Ernst Krenkel, and the leader Ivan Papanin[16] conducted scientific research at the station for the next nine months. By 19 February 1938, when the group was picked up by the ice breakersTaimyr and Murman, their station had drifted 2850 km to the eastern coast of Greenland.[17][18]
1940–2000[edit]
In May 1945 an RAF Lancaster of the Aries expedition became the first Commonwealth aircraft to overfly the North Geographic and North Magnetic Poles. The plane was piloted by David Cecil McKinley of the Royal Air Force. It carried an 11-man crew, with Kenneth C. Maclure of the Royal Canadian Air Force in charge of all scientific observations. In 2006, Maclure was honoured with a spot in Canada's Aviation Hall of Fame.[19]
Discounting Peary's disputed claim, the first men to set foot at the North Pole were a Soviet party[20] including geophysicists Mikhail Ostrekin and Pavel Senko, oceanographers Mikhail Somov and Pavel Gordienko,[21] and other scientists and flight crew (24 people in total)[22] of Aleksandr Kuznetsov's Sever-2 expedition (March–May 1948).[23] It was organized by the Chief Directorate of the Northern Sea Route.[24] The party flew on three planes (pilots Ivan Cherevichnyy, Vitaly Maslennikov and Ilya Kotov) from Kotelny Island to the North Pole and landed there at 4:44pm (Moscow Time, UTC+04:00) on 23 April 1948.[25] They established a temporary camp and for the next two days conducted scientific observations. On 26 April the expedition flew back to the continent.
Next year, on 9 May 1949,[26] two other Soviet scientists (Vitali Volovich and Andrei Medvedev)[27] became the first people to parachute onto the North Pole.[28] They jumped from a Douglas C-47 Skytrain, registered CCCP H-369.[29]
On 3 May 1952, U.S. Air Force Lieutenant Colonel Joseph O. Fletcher and Lieutenant William Pershing Benedict, along with scientist Albert P. Crary, landed a modified Douglas C-47 Skytrain at the North Pole. Some Western sources considered this to be the first landing at the Pole[30] until the Soviet landings became widely known.
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The United States Navy submarine USS Nautilus (SSN-571) crossed the North Pole on 3 August 1958. On 17 March 1959 USS Skate (SSN-578) surfaced at the Pole, breaking through the ice above it, becoming the first naval vessel to do so.[31]
Setting aside Peary's claim, the first confirmed surface conquest of the North Pole was that of Ralph Plaisted, Walt Pederson, Gerry Pitzl and Jean Luc Bombardier, who traveled over the ice by snowmobile and arrived on 19 April 1968. The United States Air Force independently confirmed their position.
On 6 April 1969, Wally Herbert and companions Allan Gill, Roy Koerner and Kenneth Hedges of the British Trans-Arctic Expedition became the first men to reach the North Pole on foot (albeit with the aid of dog teams andairdrops). They continued on to complete the first surface crossing of the Arctic Ocean – and by its longest axis, Barrow, Alaska to Svalbard – a feat that has never been repeated.[32][33] Because of suggestions (later proven false) of Plaisted's use of air transport, some sources classify Herbert's expedition as the first confirmed to reach the North Pole over the ice surface by any means.[33][34] In the 1980s, Plaisted's pilots Weldy Phipps and Ken Lee signed affidavits asserting that no such airlift was provided.[35] It is also said that Herbert was the first person to reach the pole of inaccessibility.[36]
On 17 August 1977, the Soviet nuclear-powered icebreaker Arktika completed the first surface vessel journey to the North Pole.
In 1982 Ranulph Fiennes and Charles R. Burton became the first people to cross the Arctic Ocean in a single season. They departed from Cape Crozier, Ellesmere Island, on 17 February 1982 and arrived at the geographic North Pole on 10 April 1982. They travelled on foot and snowmobile. From the Pole, they travelled towards Svalbard but, due to the unstable nature of the ice, ended their crossing at the ice edge after drifting south on an ice floe for 99 days. They were eventually able to walk to their expedition ship MV Benjamin Bowring and boarded it on 4 August 1982 at position 80:31N 00:59W. As a result of this journey, which formed a section of the three-year Transglobe Expedition 1979–1982, Fiennes and Burton became the first people to complete a circumnavigation of the world via both North and South Poles, by surface travel alone. This achievement remains unchallenged to this day.
In 1985, Sir Edmund Hillary (the first man to stand on the summit of Mount Everest) and Neil Armstrong (the first man to stand on the moon) landed at the North Pole in a small twin-engined ski plane.[37] Hillary thus became the first man to stand at both poles and on the summit of Everest.
In 1986, Will Steger, with seven teammates, became the first to be confirmed as reaching the Pole by dogsled and without resupply.
On 6 May 1986, USS Archerfish (SSN 678), USS Ray (SSN 653) and USS Hawkbill (SSN 666) surfaced at the North Pole, the first tri-submarine surfacing at the North Pole.
On 21 April 1987, Shinji Kazama of Japan became the first person to reach the North Pole on a motorcycle.[38][39]
On 18 May 1987, USS Billfish (SSN 676), USS Sea Devil (SSN 664) and HMS Superb (S 109) surfaced at the North Pole, the first international surfacing at the North Pole.
In 1988, a 13-man strong team (9 Soviets, 4 Canadians) skied across the arctic from Siberia to northern Canada. One of the Canadians, Richard Weber became the first person to reach the Pole from both sides of the Arctic Ocean.
On 4 May 1990, Børge Ousland and Erling Kagge became the first explorers ever to reach the North Pole unsupported, after a 58-day ski trek from Ellesmere Island in Canada, a distance of 800 km.[40]
On 7 September 1991, the German research vessel Polarstern and the Swedish icebreaker Oden reached the North Pole as the first conventional powered vessels.[41] Both scientific parties and crew took oceanographic and geological samples and had a commontug of war and a football game on an ice floe. Polarstern again reached the pole exactly 10 years later[42] with the Healy.
In 1998, 1999, and 2000 Lada Niva Marshs (special very large wheeled versions made by BRONTO, Lada/Vaz's experimental product division) were driven to the North Pole.[43][44] The 1998 expedition was dropped by parachute and completed the track to the North Pole. The 2000 expedition departed from a Russian research base around 114 km from the Pole and claimed an average speed of 20–15 km/h in an average temperature of −30 degrees.
21st century[edit]
In recent years, journeys to the North Pole by air (landing by helicopter or on a runway prepared on the ice) or by icebreaker have become relatively routine, and are even available to small groups of tourists through adventure holiday companies. Parachute jumps have frequently been made onto the North Pole in recent years. The temporary seasonal Russian camp of Barneo has been established by air a short distance from the Pole annually since 2002, and caters for scientific researchers as well as tourist parties. Trips from the camp to the Pole itself may be arranged overland or by helicopter.
The first attempt at underwater exploration of the North Pole was made on 22 April 1998 by Russian firefighter and diver Andrei Rozhkov with the support of the Diving Club of Moscow State University, but ended in fatality. The next attempted dive at the North Pole was organized the next year by the same diving club, and ended in success on 24 April 1999. The divers were Michael Wolff (Austria), Brett Cormick (UK), and Bob Wass (USA).[45]
In 2005, the United States Navy submarine USS Charlotte (SSN-766) surfaced through 155 cm (61 in) of ice at the North Pole and spent 18 hours there.[46]
In July 2007, British endurance swimmer Lewis Gordon Pugh completed a 1 km (0.62 mi) swim at the North Pole. His feat, undertaken to highlight the effects of global warming, took place in clear water that had opened up between the ice floes.[47] His later attempt to paddle a kayak to the North Pole in late 2008, following the erroneous prediction of clear water to the Pole, was stymied when his expedition found itself stuck in thick ice after only three days. The expedition was then abandoned.
By September 2007 the North Pole had been visited 66 times by different surface ships: 54 times by Soviet and Russian icebreakers, 4 times by Swedish Oden, 3 times by German Polarstern, 3 times by USCGC Healy and USCGC Polar Sea, and once by CCGSLouis S. St-Laurent and by Swedish Vidar Viking.[48]
2007 descent to the North Pole seabed[edit]
Main article: Arktika 2007
On 2 August 2007, a Russian scientific expedition Arktika 2007 made the first ever manned descent to the ocean floor at the North Pole, to a depth of 4.3 km (2.7 mi), as part of the research programme in support of Russia's2001 extended continental shelf claim to a large swathe of the Arctic Ocean floor. The descent took place in two MIR submersibles and was led by Soviet and Russian polar explorer Artur Chilingarov. In a symbolic act of visitation, the Russian flag was placed on the ocean floor exactly at the Pole.[49][50][51]
The expedition was the latest in a series of efforts intended to give Russia a dominant influence in the Arctic according to the New York Times.[52] The warming Arctic climate and summer shrinkage of the iced area has attracted the attention of many countries, such as China and the United States, toward the top of the world, where resources and shipping routes may soon be exploitable.[53]
MLAE 2009 Expedition[edit]
In 2009, the Russian Marine Live-Ice Automobile Expedition—MLAE 2009 (Vasily Elagin as a leader, and a team of Sergey Larin, Afanasy Makovnev, Vladimir Obikhod, Alexey Ushakov, Alexey Shkrabkin, and Nikolay Nikulshin) reached the North Pole on two custom-built 6 x 6 low-pressure-tire ATVs—Yemelya 1 and Yemelya 2—designed by Vasily Elagin, a known Russian mountain climber, explorer, and engineer. The vehicles reached the North Pole on 26 April 2009, 17:30 (Moscow time). The expedition was supported by the Russian Geographical Society.[54] The Russian Book of Records recognized it as the first successful vehicle trip to the Geographical North Pole.
MLAE 2013 Expedition[edit]
On 1 March 2013, the Russian Marine Live-Ice Automobile Expedition — MLAE 2013 (Vasily Elagin as a leader, and a team of Andrey Vankov, Sergey Isayev, Nikolay Kozlov, Afanasy Makovnev, Vladimir Obikhod, and Alexey Shkrabkin) on two custom-built 6 x 6 low-pressure-tire ATVs—Yemelya 3 and Yemelya 4—started from Golomyanny Island (the Severnaya Zemlya Archipelago) to the North Pole across drifting ice of the Arctic Ocean. The vehicles reached the Pole on 6 April and then continued to the Canadian coast. The coast was reached on 30 April 2013 (83°08N, 075°59W), and on 5 May 2013, the expedition finished in Resolute Bay, NU. The way between the Russian borderland (Machtovyi Island of the Severnaya Zemlya Archipelago, 80°15N, 097°27E) and the Canadian coast (83°08N, 075°59W) took 55 days; it was ~2300 km across drifting ice and about 4000 km in total. The expedition was totally self-dependent and used no external supplies. The expedition was supported by the Russian Geographical Society.[54]
Day and night[edit]
The sun at the North Pole is continuously above the horizon during the summer and continuously below the horizon during the winter. Sunrise is just before the March equinox (around 20 March); the sun then takes three months to reach its highest point of near 23½° elevation at the summer solstice (around 21 June), after which time it begins to sink, reaching sunset just after the September equinox (around 23 September). When the sun is visible in the polar sky, it appears to move in a horizontal circle above the horizon. This circle gradually rises from near the horizon just after the vernal equinox to its maximum elevation (in degrees) above the horizon at summer solstice and then sinks back toward the horizon before sinking below it at the autumnal equinox.
A civil twilight period of about two weeks occurs before sunrise and after sunset, a nautical twilight period of about five weeks occurs before sunrise and after sunset and an astronomical twilight period of about seven weeks occurs before sunrise and after sunset.
These effects are caused by a combination of the Earth's axial tilt and its revolution around the sun. The direction of the Earth's axial tilt, as well as its angle relative to the plane of the Earth's orbit around the sun, remains very nearly constant over the course of a year (both change very slowly over long time periods). At northern midsummer the North Pole is facing towards the sun to its maximum extent. As the year progresses and the Earth moves around the sun, the North Pole gradually turns away from the sun until at midwinter it is facing away from the Sun to its maximum extent. A similar sequence is observed at the South Pole, with a six-month time difference.
Time[edit]
In most places on Earth, local time is determined by longitude, such that the time of day is more-or-less synchronised to the position of the sun in the sky (for example, at midday the sun is roughly at its highest). This line of reasoning fails at the North Pole, where the sun rises and sets only once per year, and all lines of longitude, and hence all time zones, converge. There is no permanent human presence at the North Pole and no particular time zone has been assigned. Polar expeditions may use any time zone that is convenient, such as Greenwich Mean Time, or the time zone of the country from which they departed.
Climate[edit]
Main article: Climate of the Arctic
See also: Climate change in the Arctic
The North Pole is substantially warmer than the South Pole because it lies at sea level in the middle of an ocean (which acts as a reservoir of heat), rather than at altitude on a continental land mass.
Winter temperatures at the North Pole can range from about −50 to −13 °C (−58 to 9 °F), averaging around −31 °C (−24 °F).A However, a freak storm caused the temperature to reach 0.7 °C (33 °F) for a time at aWorld Meteorological Organization buoy, located at 87.45°N, on December 30, 2015. It was estimated that the temperature at the North Pole was between 30 and 35 °F (−1 and 2 °C) during the storm.[55] Summer temperatures (June, July, and August) average around the freezing point (0 °C (32 °F)). The highest temperature yet recorded is 13 °C (55 °F),[56] much warmer than the South Pole's record high of only −12.3 °C (9.9 °F).[57]
The sea ice at the North Pole is typically around 2 to 3 m (6 ft 7 in to 9 ft 10 in) thick,[58] although ice thickness, its spatial extent, and the fraction of open water within the ice pack can vary rapidly and profoundly in response to weather and climate.[59] Studies have shown that the average ice thickness has decreased in recent years.[60] It is likely that global warming has contributed to this, but it is not possible to attribute the recent abrupt decrease in thickness entirely to the observed warming in the Arctic.[61] Reports have also predicted that within a few decades the Arctic Ocean will be entirely free of ice in the summer.[62] This may have significant commercial implications; see "Territorial Claims," below.
The retreat of the Arctic sea ice will accelerate global warming, as less ice cover reflects less solar radiation, and may have serious climate implications by contributing to Arctic cyclone generation.[63]
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