The Arctic (; ) is the polar region of Earth that surrounds the North Pole, lying north of the Arctic Circle. The Arctic region, from the IERS Reference Meridian travelling east, consists of parts of northern Norway (Nordland, Troms, Finnmark, Svalbard and Jan Mayen), northernmost Sweden (Västerbotten, Norrbotten and Lappland), northern Finland (North Ostrobothnia, Kainuu and Lappi), Russia (Murmansk, Siberia, Nenets Okrug, Novaya Zemlya), the United States (Alaska), Canada (Yukon, Northwest Territories, Nunavut), Danish Realm (Greenland), and northern Iceland (Grímsey and Kolbeinsey), along with the Arctic Ocean and adjacent seas.
Land within the Arctic region has seasonally varying snow and ice cover, with predominantly treeless permafrost under the tundra. Arctic seas contain seasonal sea ice in many places.
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. Life in the Arctic includes zooplankton and phytoplankton, fish and marine mammals, birds, land animals, plants, and human societies. Arctic land is bordered by the subarctic.
Definition and etymology The word Arctic comes from the Greek word arktikos "near the Bear, northern" and from the word arktos meaning "bear," named for either the constellation known as Ursa Major, the "Great Bear", which is prominent in the northern portion of the celestial sphere, or the constellation Ursa Minor, the "Little Bear", which contains the celestial north pole (currently very near Polaris, the current north Pole Star, or North Star).
There are several definitions of what area is contained within the Arctic. The area can be defined as north of the Arctic Circle (about 66° 34'N), the approximate southern limit of the midnight sun and the polar night. Another definition of the Arctic, which is popular with ecologists, is the region in the Northern Hemisphere where the average temperature for the warmest month (July) is below ; the northernmost tree line roughly follows the isotherm at the boundary of this region.
Climate
The climate of the Arctic region is characterized by cold winters and cool summers. Its precipitation mostly comes in the form of snow and is low, with most of the area receiving less than . High winds often stir up snow, creating the illusion of continuous snowfall. Average winter temperatures can go as low as , and the coldest recorded temperature is approximately . Coastal Arctic climates are moderated by oceanic influences, having generally warmer temperatures and heavier snowfalls than the colder and drier interior areas. The Arctic is affected by current global warming, leading to climate change in the Arctic, including Arctic sea ice decline, diminished ice in the Greenland ice sheet, and Arctic methane emissions as the permafrost thaws. The melting of Greenland's ice sheet is linked to polar amplification.
Due to the poleward migration of the planet's isotherms (about per decade during the past 30 years as a consequence of global warming), the Arctic region (as defined by tree line and temperature) is currently shrinking. Perhaps the most alarming result of this is Arctic sea ice shrinkage. There is a large variance in predictions of Arctic sea ice loss, with models showing near-complete to complete loss in September from 2035 to sometime around 2067.
Flora and fauna
Arctic life is characterized by adaptation to short growing seasons with long periods of sunlight, and cold, dark, snow-covered winter conditions, with soil depth constrained by permafrost. In the Arctic Circle, up to 24 hours of daylight is experienced at the summer solstice in June and up to 24 hours of darkness during the winter solstice in December which has an important impact on the ecology of the region.
Plants
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. An example of a dwarf shrub is the bearberry. 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 in height; sedges, mosses and lichens can form thick layers. In the coldest parts of the Arctic, much of the ground is bare; non-vascular plants such as lichens and mosses predominate, along with a few scattered grasses and forbs (like the Arctic poppy).
Animals
Herbivores on the tundra include the Arctic hare, lemming, muskox, and reindeer (caribou). They are preyed on by the snowy owl, Arctic fox, grizzly bear, and Arctic wolf. The polar bear is also a predator, though it prefers to hunt for marine life from the ice. There are also many birds (some 200 species breed in the Arctic) and marine species endemic to the colder regions. Other terrestrial animals include wolverines, moose, Dall sheep, ermines, and Arctic ground squirrels. Marine mammals include seals, walruses, and several species of cetacean—baleen whales and also narwhals, orcas, and belugas.
Natural resources
There are copious natural resources in the Arctic (oil, gas, minerals, freshwater, fish, and, if the subarctic is included, forest) to which modern technology and the economic opening up of Russia have given significant new opportunities. The interest in the tourism industry is also on the increase.
The Arctic contains some 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 breeding grounds of the animals that are characteristic of the region. The Arctic also holds 1/5 of the Earth's water supply.
Paleontology During the Cretaceous period, the Arctic still had seasonal snows, though only a light dusting and not enough to permanently hinder plant growth. Animals such as the 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 winter came. A similar situation may also have been found amongst dinosaurs that lived in Antarctic regions, such as the Muttaburrasaurus of Australia.
However, others claim that dinosaurs lived year-round at very high latitudes, such as near the Colville River, which is now at about 70° N but at the time (70 million years ago) was 10° further north.
Indigenous population
The earliest inhabitants of North America's central and eastern Arctic are referred to as the Arctic small tool tradition (AST) and existed . AST consisted of several Paleo-Eskimo cultures, including the Independence cultures and Pre-Dorset cultures. in The Dorset culture (Inuktitut: Tuniit or Tunit) refers to the next inhabitants of central and eastern Arctic. The Dorset culture emerged across the North American Arctic through a gradual process of cultural and technological adaptation to changing environmental conditions and resource availability between 1050 and 500 BCE. With the exception of the Quebec / Labrador peninsula, the Dorset culture vanished around 1500 CE. in Supported by genetic testing, evidence shows that descendants of the Dorset culture, known as the Sadlermiut, survived in Aivilik, Southampton and Coats Islands, until the beginning of the 20th century.
The Dorset / Thule culture transition dates around the ninth–10th centuries CE. Scientists theorize that there may have been cross-contact between the two cultures with the sharing of technology, such as fashioning harpoon heads, or the Thule may have found Dorset remnants and adapted their ways with the predecessor culture. in The evidence suggested that Inuit descend from the Birnirk of Siberia, through the Thule culture expanded into northern Canada and Greenland, where they genetically and culturally completely replaced the Indigenous Dorset people sometime after 1300 CE. The question of why the Dorset disappeared so completely has led some to suggest that Thule invaders wiped out the Dorset people in "an example of prehistoric genocide."
By 1300 CE, the Inuit, present-day Arctic inhabitants and descendants of Thule culture, had settled in west Greenland and moved into east Greenland over the following century (Inughuit, Kalaallit and Tunumiit are modern Greenlandic Inuit groups descended from Thule). Over time, the Inuit have migrated throughout the Arctic regions of Eastern Russia, the United States, Canada, and Greenland.
Other Circumpolar North indigenous peoples include the Chukchi, Evenks, Iñupiat, Khanty, Koryaks, Nenets, Sámi, Yukaghir, Gwichʼin, and Yupik.
International cooperation and politics
The eight Arctic nations (Canada, Kingdom of Denmark [Greenland & The Faroe Islands], Finland, Iceland, Norway, Sweden, Russia, and US) are all members of the Arctic Council, as are organizations representing six indigenous populations (The Aleut International Association, Arctic Athabaskan Council, Gwich'in Council International, Inuit Circumpolar Council, Russian Association of Indigenous Peoples of the North, and Saami Council). The council operates on a consensus basis, mostly dealing with environmental treaties and not addressing boundary or resource disputes.
Though Arctic policy priorities differ, every Arctic nation is concerned about sovereignty/defense, resource development, shipping routes, and environmental protection. Much work remains on regulatory agreements regarding shipping, tourism, and resource development in Arctic waters. Arctic shipping is subject to some regulatory control through the International Code for Ships Operating in Polar Waters, adopted by the International Maritime Organization on 1 January 2017 and applies to all ships in Arctic waters over 500 tonnes.
Research in the Arctic has long been a collaborative international effort, evidenced by the International Polar Year. The International Arctic Science Committee, hundreds of scientists and specialists of the Arctic Council, and the Barents Euro-Arctic Council are more examples of collaborative international Arctic research.
Territorial claims
While there are several ongoing territorial claims in the Arctic, no country owns the geographic North Pole or the region of the Arctic Ocean surrounding it. The surrounding six Arctic states that border the Arctic Ocean—Canada, the Kingdom of Denmark (with Greenland), Iceland, Norway, Russia, and the United States—are limited to a exclusive economic zone (EEZ) off their coasts. Two Arctic states (Finland and Sweden) do not have direct access to the Arctic Ocean.
Upon ratification of the United Nations Convention on the Law of the Sea, a country has ten years to make claims to an extended continental shelf beyond its 200 nautical mile zone. Due to this, Norway (which ratified the convention in 1996), Russia (ratified in 1997), Canada (ratified in 2003) and the Kingdom of Denmark (ratified in 2004) launched projects to establish claims that certain sectors of the Arctic seabed should belong to their territories.