Arctic - North Pole
The Arctic is the region around the Earth's North Pole, opposite the Antarctic region around the South Pole. The Arctic includes the Arctic Ocean (which overlies the North Pole) and parts of Canada, Greenland (a territory of Denmark), Russia, the United States (Alaska), Iceland, Norway, Sweden and Finland.
The word Arctic comes from the Greek (arktikos), "near the Bear, arctic, northern" and that from the word (arktos), which means bear. The name refers to the constellation Ursa Major, the "Great Bear", which is prominent in the northern portion of the celestial sphere.
There are many definitions of the Arctic region. The boundary is generally considered to be north of the Arctic Circle (66 degrees 33 minutes N), which is the approximate limit of the midnight sun and the polar night. Other definitions are based on climate and ecology, such as the 10 degrees C (50 degrees F) July isotherm, which roughly corresponds to the tree line in most of the Arctic. Socially and politically, the Arctic region includes the northern territories of the eight Arctic states, including Sapmi, although by natural science definitions much of this territory is considered subarctic.
The Arctic region consists of a vast ice-covered ocean (which is sometimes considered to be a northern arm of the Atlantic Ocean) surrounded by treeless permafrost. In recent years the extent of the sea ice has declined. Life in the Arctic includes organisms living in the ice, zooplankton and phytoplankton, fish and marine mammals, birds, land animals, plants, and human societies.
The Arctic region is a unique area among Earth's ecosystems. The cultures in the region and the Arctic indigenous peoples have adapted to its cold and extreme conditions.
If the region is defined by the isotherm, then Arctic shrinkage is currently taking place due to global warming. The Arctic is projected to be free of sea ice as early as 2013, although other estimates exist.
This ice loss is linked to loss of permafrost and clathrates, which contain large quantities of methane. Many scientists believe this will cause a catastrophic Arctic methane release, potentially leading to runaway climate change. This rapid climate feedback process may be unstoppable unless geoengineering is used. Arctic geoengineering may be employed specifically to preserve ice cover.
Arctic vegetation is composed of plants such as dwarf shrubs, graminoids, herbs, lichens and mosses, which all grow relatively close to the ground, forming tundra. As one moves northward, the amount of warmth available for plant growth decreases considerably. In the northernmost areas, plants are at their metabolic limits, and small differences in the total amount of summer warmth make large differences in the amount of energy available for maintenance, growth and reproduction. Colder summer temperatures cause the size, abundance, productivity and variety of plants to decrease. Trees cannot grow in the Arctic, but in its warmest parts, shrubs are common and can reach 2 m (6 ft 7 in) in height; sedges, mosses and lichens can form thick layers. In the coldest parts of the Arctic, much of the ground is bare; nonvascular plants such as lichens and mosses predominate, along with a few scattered grasses and forbs (like the Arctic poppy).
Herbivores on the Tundra include the Arctic hare, lemming, muskox, and caribou. They are preyed on by the Arctic fox and wolf. The polar bear is also a predator, though it prefers to hunt for marine life from the ice. There are also many birds and marine species endemic to the colder regions. Other land animals include wolverines, ermines, and arctic ground squirrels. Marine mammals include seals, walrus, and several species of cetacean - baleen whales and also narwhals, killer whales and belugas.
The Arctic includes sizable natural resources (oil, gas, minerals, forest - if the subarctic is included - and fish) to which modern technology and the economic opening up of Russia have given significant new opportunities. The interest of the tourism industry is also on the increase.
The Arctic is one of the last and most extensive continuous wilderness areas in the world, and its significance in preserving biodiversity and genotypes is considerable. The increasing presence of humans fragments vital habitats. The Arctic is particularly susceptible to the abrasion of groundcover and to the disturbance of the rare reproduction places of the animals that are characteristic to the region. The Artctic also holds 1/5 of the Earth water supply.
During the Cretaceous, the Arctic still had seasonal snows, though only a light dusting and not enough to permanently hinder plant growth.[citation needed] Animals such as Chasmosaurus, Hypacrosaurus, Troodon, and Edmontosaurus may have all migrated north to take advantage of the summer growing season, and migrated south to warmer climes when the winter came. A similar situation may also have been found amongst dinosaurs that lived in Antarctic regions, such as Muttaburrasaurus of Australia.
The Inuit are the descendants of what anthropologists call the Thule culture, a nomadic people who emerged from western Alaska around 1000 CE and spread eastwards across the Arctic, displacing the related Dorset culture (in Inuktitut, the Tuniit). Inuit legends speak of the Tuniit as "giants", people who were taller and stronger than the Inuit, but who were easily scared off and retreated from the advancing Inuit. Researchers believe that the Dorset culture lacked dogs, boats and other technologies that gave the expanding Inuit society a large advantage over them. By 1300, the Inuit had settled west Greenland, and finally moved into east Greenland over the following century.
The Tuniit survived in Aivilik, Southampton and Coats Islands, until the beginning of the 20th century. They were known as Sadlermiut (Sallirmiut in the modern spelling). Their population had been ravaged by diseases brought by contact with Europeans, and the last of them fell in a flu epidemic caught from a passing whaler in 1902. The area has since been resettled by Inuit. Genetic research suggests that there was little or no intermarriage between the Tuniit and the Inuit over the thousand years of contact in the Canadian Arctic.
The Arctic region is a focus of international political interest. International Arctic cooperation got underway on a broad scale well over ten years ago. The International Arctic Science Committee (IASC), hundreds of scientists and specialists of the Arctic Council, the Barents Euro-Arctic Council and its regional cooperation have compiled high quality information on the Arctic.
No country owns the North Pole or the region of the Arctic Ocean surrounding it. The surrounding Arctic states, the United States, Canada, Russia, Norway and Denmark (via Greenland), are limited to a 370 kilometre (200 nautical mile) economic zone around their coasts.
Upon ratification of the United Nations Convention on the Law of the Sea, a country has ten years to make claims to extend its 200 mile zone. Due to this, Norway (ratified the convention in 1996), Russia (ratified in 1997), Canada (ratified in 2003) and Denmark (ratified in 2004) launched projects to establish claims that certain Arctic sectors should belong to their territories.
On August 2, 2007, two Russian bathyscaphes, MIR-1 and MIR-2, for the first time in history descended to the Arctic seabed beneath the North Pole and placed there a Russian flag made of rust-proof titanium alloy. The mission was a scientific expedition, but the flag-placing raised concerns of a race for control of the Arctic's vast petroleum resources.
Foreign Ministers and other officials representing Canada, Denmark, Norway, Russia, and the United States met in Ilulissat, Greenland on May 28, 2008 at the Arctic Ocean Conference and announced the Ilulissat Declaration.
The Arctic is comparatively clean, although there are certain ecologically difficult localized pollution problems that present a serious threat to people's health living around these pollution sources. Due to the prevailing worldwide sea and air currents, the Arctic area is the fallout region for long-range transport pollutants, and in some places the concentrations exceed the levels of densely populated urban areas. An example of this is the phenomenon of Arctic haze, which is commonly blamed on long-range pollutants. Another example is with the bioaccumulation of PCB's (polychlorinated biphenyls) in Arctic wildlife and people.
The Arctic is especially vulnerable to the effects of global warming as has become apparent in the melting sea ice in recent years. Climate models predict much greater warming in the Arctic than global average. This fact has garnered significant international attention to the region. In particular, there are concerns that Arctic shrinkage, a consequence of melting glaciers and other ice in Greenland, could soon contribute to a substantial rise in sea levels worldwide.
A recent study by a research group at Naval Postgraduate School, Monterey, California working with members of NASA and the Institute of Oceanology at the Polish Academy of Sciences estimate that the Arctic sea could be ice-free in the summer as soon as 2013.
The Arctic sea ice melted at an unprecedented rate, well ahead of the estimates generated by climate models, in 2007.
In September 2008, the extent of the summer Arctic ice cap was at a near-record low, only 9 percent greater than the record low in 2007, and 33.6 percent below the average extent of sea ice from 1979 to 2000.
The current Arctic shrinkage is leading to widespread fears of a potentially catastrophic Arctic methane release. Release of methane stored in clathrates and permafrost could have a devastating effect on the Earth's atmosphere and could cause abrupt and severe global warming, as methane is a potent greenhouse gas. Similar methane release events have been linked to the great dying (a mass extinction event) and the Paleocene-Eocene thermal maximum (an abrupt climate change event). This process of Arctic methane release may cause positive feedback effects which rapidly accelerate global warming, due to the clathrate gun effect.
Apart from concerns regarding the detrimental effects of warming in the Arctic, some potential opportunities have gained attention as well. However, it should be noted that these advantages are minor compared to the risk of runaway global warming. The melting of the ice is making the so-called Northwest passage, the shipping routes through the northern-most latitudes, more navigable, raising the possibility that the Arctic region will become a prime trade route.
In addition, it is believed that the Arctic seabed may contain substantial oil fields which may become accessible if the ice covering them melts. These factors have led to recent international debates as to which nations can claim sovereignty or ownership over the waters of the Arctic.
NOAA's Arctic Report Card presents annually-updated, peer-reviewed information on recent observations of environmental conditions in the Arctic relative to historical records. In 2008, there continues to be widespread and, in some cases, dramatic evidence of an overall warming of the Arctic system.
Wikipedia References and Links
The pole is located in the Arctic Ocean. Classically (19th century) this pole was exactly where people believed the pole of rotation met the Earth's surface, but soon astronomers noticed a small apparent variation of latitude as determined for a fixed point on Earth by observing stars.
This variation had a period of about 435 days and the periodic part of it is now called the Chandler wobble after its discoverer. It is desirable to tie the system of Earth coordinates (latitude, longitude, and elevations or orography) to fixed landforms.
Of course, given continental drift and the rising and falling of land due to volcanos, erosion and so on, 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 that does an admirable job.
The North pole of this system now defines geographic North and it does not quite coincide with the rotation axis. Also see polar motion.
On the basis of the sector principle, Canada claims its sovereignty to extend all the way to the Geographic North Pole. There is no land at this location, which is usually covered by sea ice.
The theory under which Canada has claimed sovereignty to the North Pole is controversial as there is in fact 770 km of ocean between the pole and Canada's northernmost land point, and several nations, most notably the United States, have challenged the notion that the North Pole does not lie in international waters.
Magnetic North is the place to which all magnetic compasses point, although since the pole marked "N" on a bar magnet points north, and only opposite magnetic poles are attracted to each other, the Earth's magnetic north is actually a south magnetic pole.
The orientation of magnetic fields of planets can flip over, an event which is called a geomagnetic reversal. The Earth's poles have done this repeatedly throughout history, and 500,000 years ago, the south magnetic pole was at the South Pole. It is thought that this occurs when the circulation of liquid nickel/iron in the Earth's outer core is disrupted and then reestablishes itself in the opposite direction. It is not known what causes these disruptions.
Proof of this can be seen at mid-ocean ridges where tectonic plates move apart, and the sea bed is filled in with magma. As the magma comes out of the mantle, the magnetic particles in it are attracted slightly to the North Pole, and when the poles switch, so does the direction in which the metallic elements face. Therefore, on the sea bed, parallel bands of alternating magnetic fields are found.
The first expedition to reach this pole was led by James Clark Ross, who found it at Cape Adelaide on the Boothia Peninsula on June 1, 1831. Roald Amundsen found Magnetic North in a slightly different location in 1903. The third observation of Magnetic North was by Canadian government scientists Paul Serson and Jack Clark, of the Dominion Astrophysical Observatory, who found the pole at Allen Lake on Prince of Wales Island.
The Canadian government has made several measurements since, which show that Magnetic North is continually moving northwest.
If it maintains its present speed and direction it will reach Siberia in about 50 years, but it is expected to veer from its present course and slow down.This movement is on top of a daily or diurnal variation in which Magnetic North describes a rough ellipse, with a maximum deviation of 80 km from its mean position. This effect is due to disturbances of the geomagnetic field by the sun.
A line drawn from one magnetic pole to the other does not go through the centre of the Earth; it actually misses it by about 530 km.The angular difference between Magnetic North and true North varies with location, and is called the magnetic declination.
The Geomagnetic poles are the places where the axis of this dipole intersects the Earth's surface. Because the dipole approximation is far from a perfect fit to the Earth's magnetic field, the magnetic field is not quite vertical at the geomagnetic poles.
The locations of true vertical field orientation are the magnetic poles, and these are about 30 degrees of longitude away from the geomagnetic poles.
Like the Magnetic North Pole, the geomagnetic north pole is a south magnetic pole, because it attracts the north pole of a bar magnet.
It is the center of the region in the magnetosphere in which the Aurora Borealis can be seen. Its present location is 78 degrees 30' North, 69 degrees West, near Qaanaaq in Greenland, however it is now drifting away from North America and toward Siberia. The first voyage to this pole was by David Hempleman-Adams in 1992.
Northern Pole of Inaccessibility
Defining North Poles in astronomy
Astronomers define the north "geographic" pole of a planet or other object in the solar system by the planetary pole that is in the same ecliptic hemisphere as the Earth's north pole. More accurately, The north pole is that pole of rotation that lies on the north side of the invariable plane of the solar system.
This means some objects will have directions of rotation opposite the "normal" (i.e., not counter-clockwise as seen from above the north pole). Another frequently used definition uses the right-hand rule to define the north pole: it is then the pole around which the object rotates counterclockwise.
When using the first definition (the IAU's), an object's axial tilt will always be 90 degrees or less, but its rotation period may be negative (retrograde rotation); when using the second definition, axial tilts may be greater than 90 degrees but rotation periods will always be positive.
For the magnetic poles, their names are decided upon by the direction that their field lines emerge or enter the planet's crust. If they enter the same way as they do for Earth at the north pole, we call this the planet's north magnetic pole.
Some bodies in the solar system, including Saturn's moon Hyperion and the asteroid 4179 Toutatis, lack a stable geographic north pole. They rotate chaotically because of their irregular shape and gravitational influences from nearby planets and moons, and as a result the instantaneous pole wanders over their surface, and may vanish altogether for brief periods (when the object comes to a complete standstill with respect to the distant stars).
The projection of a planet's north geographic pole onto the celestial sphere gives its north celestial pole.In the particular (but frequent) case of synchronous satellites, four more poles can be defined. They are the near, far, leading, and trailing poles. Take Io for example; this moon of Jupiter rotates synchronously, so its orientation with respect to Jupiter stays constant.
There will be a single, unmoving point of its surface where Jupiter is at the zenith, exactly overhead - this is the near pole, also called the sub- or pro-Jovian point. At the antipode of this point is the far pole, where Jupiter lies at the nadir; it is also called the anti-Jovian point.
There will also be a single unmoving point which is furthest along Io's orbit (best defined as the point most removed from the plane formed by the north-south and near-far axes, on the leading side) - this is the leading pole. At its antipode lies the trailing pole. Io can thus be divided into north and south hemispheres, into pro- and anti-Jovian hemispheres, and into leading and trailing hemispheres.
Note that these poles are mean poles because the points are not, strictly speaking, unmoving: there is constant jiggling about the mean orientation, because Io's orbit is slightly eccentric and the gravity of the other moons disturbs it regularly.
Day and Night
During the summer months, the North Pole experiences twenty-four hours of daylight daily but during the winter months the North Pole experiences twenty-four hours of darkness daily. Sunrise and sunset do not occur in a twenty-four hour cycle. At the north pole, sunrise begins at the Vernal equinox taking three months for the sun to reach its highest point at the summer solstice when sunset begins, taking three months to reach sunset at the Autumnal equinox. A similar effect can be observed at the South Pole, with a six month difference. This day/night effect is in stark contrast to what is observed at the Equator.
This effect is caused by a combination of the Earth's axial tilt and its rotation around the sun. The direction and angle of axial tilt of the Earth remains fairly constant (on a yearly basis) in its plane of rotation around the sun. Hence during the summer, the North Pole is always facing the sun's rays but during the winter, it always faces away from the sun.
Territorial Claims to the North Pole (Arctic)
In 1925, based upon the Sector Principle, Canada became the first country to extend its boundaries northward to the North Pole, at least on paper, between 60 degrees W and 141 degrees W longitude, a claim that is not universally recognized. In addition, Canada claims the water between its Arctic Islands as internal waters. The claim is not recognized by the United States, which argues the Northwest Passage is an international waterway, despite its minimal usage for shipping. Denmark (Greenland), Russia and Norway have made similar claims, which are also opposed by the United States and by the European Union.
Otherwise, until 1999, the North Pole and Arctic Ocean had been generally considered international territory. However, as the polar ice has begun to recede at a rate higher than expected (see global warming), several countries have made moves to claim, or to enforce pre-existing claims to, the waters or seabed at the Pole. Russia made its first claim in 2001, claiming Lomonosov Ridge, an underwater mountain ridge underneath the Pole, as a natural extension of Siberia. This claim was contested by Norway, Canada, the United States and Denmark in 2004. The Danish autonomous province of Greenland has the nearest coastline to the North Pole, and Denmark argues the Lomonosov Ridge is in fact an extension of Greenland.
The potential value of the North Pole and the area around resides not so much in shipping but in the possibility that lucrative petroleum and natural gas reserves exist below the sea floor. Such reserves are known to exist under the Beaufort Sea, and further exploration elsewhere in the Arctic might become more feasible if global warming opens up the Northwest Passage as a regular channel of international shipping and commerce, particularly if Canada is not able to enforce her claim to it.
Magnetic north is determined by the earth's magnetic field and is not the same as true (or geographic) north. The location of the magnetic north pole changes slowly over time, but it is currently northwest of Hudson Bay in northern Canada (approximately 700 km [450 mi] from the true north pole). Maps are based on the geographic north pole because it does not change over time, so north is always at the top of a quadrangle map. However, if you were walk a straight line following the direction your compass needle indicates as north, you would find that you didn't go from south to north on the map.
How far your path varied from true north depends on where you started from; the angle between a straight north-south line and the line you walked is the magnetic declination in the area you were walking. Magnetic declination has been measured throughout the U.S. and can be corrected for on your compass.
The line of zero declination runs from magnetic north through Lake Superior and across the western panhandle of Florida. Along this line, true north is the same as magnetic north. If you are working west of the line of zero declination, your compass will give a reading that is east of true north. Conversely, if you are working east of the line of zero declination, your compass reading will be west of true north. The exact amount that you need to adjust the declination on your compass to reconcile magnetic north to true north is given in the map legend to the left of the map scale.
Missing 'Ice Arches' Contributed to 2007 Arctic Ice Loss Science Daily - February 23, 2010
Same Species, Polar Opposites: The Mystery of Identical Creatures Found in both Arctic and Antarctic Waters Scientific American - February 23, 2010
Trees invading warming Arctic will cause warming over entire region, study shows PhysOrg - January 12, 2010
Record Migration: Small Birds Travel 50,000 Miles Live Science - January 12, 2010
Portions of Arctic coastline eroding, no end in sight, says new study PhysOrg - December 14, 2009
Time-Lapse Photos Show Dramatic Erosion of Alaska/Arctic Coastline Live Science - December 14, 2009
"Alien" Jellyfish Found in Arctic Deep National Geographic - December 12, 2009
A final warning from the Arctic New Scientist - November 24, 2009
Arctic Now Warmest in 2000 Years, Researchers Say Epoch Times - September 3, 2009
Strange jellies of the icy depths BBC - September 1, 2009
Red-Purple Jellyfish
Arctic climate under greenhouse conditions in the Late Cretaceous PhysOrg - July 9, 2009
Ancient Creatures Survived Arctic Winters Live Science - June 5, 2009
53 million-year-old high Arctic mammals wintered in darkness PhysOrg - June 1, 2009
Dinosaurs Lived in the Arctic Live Science - April 26, 2009
Arctic team: 'London, we have a problem' BBC - April 9, 2009
Arctic Ice Got Smaller, Thinner, Younger This Winter National Geographic - April 6, 2009
Odd, Identical Species Found at Both Poles National Geographic - February 15, 2009
Ice oceans 'are not poles apart' BBC - February 15, 2009
At least 235 marine species are living in both polar regions, despite being 12,000km apart, a census has found.
Same Species Found at Both Ends of Earth Live Science - February 15, 2009
Arctic melt 20 years ahead of climate models New Scientist - December 19, 2008
Arctic ice thickness 'plummets' BBC - October 28, 2008
New Thinking on When the Arctic Froze Live Science - October 1, 2008
Arctic Ice in "Death Spiral," Is Near Record Low National Geographic - September 17, 2008
Arctic Map shows dispute hotspots BBC - August 6, 2008
Canadian Arctic sheds ice chunk BBC - July 30, 2008 A large chunk of an Arctic ice shelf has broken free of the northern Canadian coast, scientists say.
Boiling Hot Water Found in Frigid Arctic Sea Live Science - July 24, 2008
U.S. Study: Arctic Loaded with Oil and Gas Live Science - July 24, 2008
Distant Wildfires Cause Arctic Cooling Discovery - July 22, 2008
North Pole May Be Ice Free for First Time This Summer National Geographic - June 21, 2008
Thin Ice: The Arctic Meltdown Explained Live Science - June 28, 2008
Volcanoes erupting beneath Arctic ice MSNBC - June 28, 2008
Arctic Volcanoes Found Active at Unprecedented Depths National Geographic - June 27, 2008
Ice diary: Science in the fast-changing Arctic BBC - June 27, 2008
Vast cracks appear in Arctic ice BBC - May 23, 2008
Ward Hunt Ice Shelf, Largest In Northern Hemisphere, Has Fractured Into Three Main Pieces Science Daily - April 17, 2008
Mysterious "Rain on Snow" Events Tracked in Arctic National Geographic - March 4, 2008
Svalbard's giant cold store Guardian - February 26, 2008
Arctic Seed Vault Opens National Geographic - February 26, 2008
Svalbard Global Seed Vault: Seed-Protecting "Doomsday" Vault Opens National Geographic - February 26, 2008
Giant "Sea Monster" Fossil Discovered in Arctic - National Geographic - February 27, 2008
The 150-million-year-old creature was first discovered in 2006 on Spitsbergen, part of
Norway's Svalbard archipelago, in a polar wasteland littered with fossilized sea reptiles.
Sea reptile is biggest on record BBC - February 27, 2008
A fossilized "sea monster" unearthed on an Arctic island is the largest
marine reptile known to science, Norwegian scientists have announced.
The 150 million-year-old specimen was found on Spitspergen,
in the Arctic island chain of Svalbard, in 2006.
Rich life emerges from nature's freezer BBC - December 27, 2007
Tiny channels in the Arctic ice support creatures that
play a crucial role in climate-affected ecosystems.
McCall melt links the Arctic eras BBC - December 26, 2007
The dramatic springtime collapse of surface ozone in the Arctic has been documented by scientists BBC - December 14, 2007
Arctic summers ice-free 'by 2013' BBC - December 12, 2007
Arctic Sea Ice Gone in Summer Within Five Years? National Geographic - December 12, 2007
Arctic muds reveal sea ice record BBC - October 15, 2007
Russia's Arctic Claim Backed By Rocks, Officials Say National Geographic - September 21, 2007
Ice withdrawal 'shatters record' BBC - September 21, 2007
Warming 'opens Northwest Passage' BBC - September 14, 2007
Vast ice island trapped in Arctic BBC - September 1, 2007
Arctic sea ice set to hit new low BBC - August 13, 2007
Mysterious Clouds Creeping Out of the Arctic Live Science - June 29, 2007
Arctic spring's 'rapid advance' BBC - June 19, 2007
Arctic ice no barrier for plants BBC - June 15, 2007
Surprise New Arctic Inhabitants: Trees Live Science - March 9, 2007
Deep Sea, Arctic May Hold World's Largest Fuel Supply, Experts Say National Geographic - March 7, 2007
'Monster' fossil find in Arctic BBC - October 5, 2006
"treasure trove" of fossils belonging to giant sea reptiles
that roamed the seas at the time of the dinosaurs.
'Drastic' shrinkage in Arctic ice BBC - September 14, 2006
Arctic's tropical past uncovered BBC - May 31, 2006
Fifty-five million years ago the North Pole was an ice-free
zone with tropical temperatures, according to research.
'Noah's Ark' in Arctic region to be built to protect world's crop seeds from disaster News in Science - May 31, 2006
Mysterious Arctic skull raises questions about what animals once roamed North CNews - June 1, 2006
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