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Circumpolar Coastal Human Population Distribution Ca
Circumpolar may refer to: * Antarctic region ** Antarctic Circle ** the Antarctic Circumpolar Current ** Subantarctic ** List of Antarctic and subantarctic islands ** Antarctic Convergence ** Antarctic Circumpolar Wave ** Antarctic Ocean * Arctic region ** Arctic Circle ** Subarctic ** Circumpolar peoples ** Arctic Cooperation and Politics ** Arctic Ocean ** List of islands in the Arctic Ocean * Circumpolar constellation, a constellation that never rises or sets from the perspective of a given latitude on Earth ** Circumpolar star, a star that never rises or sets from the perspective of a given latitude on Earth * Polar front in meteorology * circumpolar navigation, a global circumnavigation which traverses both poles See also * Circumpolar distribution A circumpolar distribution is any range of a taxon that occurs over a wide range of longitudes but only at high latitudes; such a range therefore extends all the way around either the North Pole or the South Pole. Taxa that a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antarctic Circle
The Antarctic Circle is the most southerly of the five major circles of latitude that mark maps of Earth. The region south of this circle is known as the Antarctic, and the zone immediately to the north is called the Southern Temperate Zone. South of the Antarctic Circle, the Sun is above the horizon for 24 continuous hours at least once per year (and therefore visible at midnight) and the centre of the Sun (ignoring refraction) is below the horizon for 24 continuous hours at least once per year (and therefore not visible at noon); this is also true within the equivalent polar circle in the Northern Hemisphere, the Arctic Circle. The position of the Antarctic Circle is not fixed and currently runs south of the Equator. This figure may be slightly inaccurate because it does not allow for the effects of astronomical nutation, which can be up to 10″. Its latitude depends on the Earth's axial tilt, which fluctuates within a margin of more than 2° over a 41,000-year period, due ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arctic Cooperation And Politics
Arctic cooperation and politics are partially coordinated via the Arctic Council, composed of the eight Arctic nations: the United States, Canada, Iceland, Norway, Sweden, Finland, Russia, and Denmark with Greenland and the Faroe Islands. The dominant governmental power in Arctic policy resides within the executive offices, legislative bodies, and implementing agencies of the eight Arctic nations, and to a lesser extent other nations, such as United Kingdom, Germany, European Union and China. NGOs and academia play a large part in Arctic policy. Also important are intergovernmental bodies such as the United Nations (especially as relates to the Law of the Sea Treaty) and NATO. Though Arctic policy priorities differ, every Arctic nation is concerned about sovereignty and defense, resource development, shipping routes, and environmental protection. Though several boundary and resource disputes in the Arctic remain unsolved, there is remarkable conformity of stated policy directives a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Circumnavigation
Circumnavigation is the complete navigation around an entire island, continent, or astronomical object, astronomical body (e.g. a planet or natural satellite, moon). This article focuses on the circumnavigation of Earth. The first recorded circumnavigation of the Earth was the Magellan's circumnavigation, Magellan–Elcano expedition, which sailed from Sanlucar de Barrameda, Spain in 1519 and returned in 1522, after crossing the Atlantic Ocean, Atlantic, Pacific Ocean, Pacific, and Indian Ocean, Indian oceans. Since the rise of commercial aviation in the late 20th century, circumnavigating Earth is straightforward, usually taking days instead of years. Today, the challenge of circumnavigating Earth has shifted towards human and technological endurance, speed, and List of circumnavigations#Miscellaneous, less conventional methods. Etymology The word ''circumnavigation'' is a noun formed from the verb ''circumnavigate'', from the past participle of the Latin verb '':wikt:circumnav ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polar Front
In meteorology, the polar front is the weather front boundary between the polar cell and the Ferrel cell around the 60° latitude, near the polar regions, in both hemisphere. At this boundary a sharp gradient in temperature occurs between these two air masses, each at very different temperatures. The polar front arises as a result of cold polar air meeting warm tropical air. It is a stationary front as the air masses are not moving against each other and stays stable. Off the coast of eastern North America, especially in winter, there is a sharp temperature gradient between the snow-covered land and the warm offshore currents. The polar front theory says that mid-latitude extratropical cyclones form on boundaries between warm and cold air. In winter, the polar front shifts towards the Equator, whereas high pressure systems dominate more in the summer. See also * Polar vortex * Horse latitudes The horse latitudes are the latitudes about 30 degrees north and sou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Circumpolar Star
A circumpolar star is a star that, as viewed from a given latitude on Earth, never sets below the horizon due to its apparent proximity to one of the celestial poles. Circumpolar stars are therefore visible from said location toward the nearest pole for the entire night on every night of the year (and would be continuously visible throughout the day too, were they not overwhelmed by the Sun's glare). Others are called ''seasonal'' stars. All circumpolar stars lie within a circumpolar circle whose size is determined by the observer's latitude. Specifically, the angular measure of the radius of this circle equals the observer's latitude. The closer the observer is to the North or South Pole, the larger the circumpolar circle is. Before the definition of the Arctic was formalized as the region north of the Arctic Circle which experiences the Midnight sun, it more broadly meant those places where the 'bear' constellations (Ursa Major, the Great Bear, and Ursa Minor, the Little Bear ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Circumpolar Constellation
A circumpolar star is a star that, as viewed from a given latitude on Earth, never sets below the horizon due to its apparent proximity to one of the celestial poles. Circumpolar stars are therefore visible from said location toward the nearest pole for the entire night on every night of the year (and would be continuously visible throughout the day too, were they not overwhelmed by the Sun's glare). Others are called ''seasonal'' stars. All circumpolar stars lie within a circumpolar circle whose size is determined by the observer's latitude. Specifically, the angular measure of the radius of this circle equals the observer's latitude. The closer the observer is to the North or South Pole, the larger the circumpolar circle is. Before the definition of the Arctic was formalized as the region north of the Arctic Circle which experiences the Midnight sun, it more broadly meant those places where the 'bear' constellations (Ursa Major, the Great Bear, and Ursa Minor, the Little Bear) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of Islands In The Arctic Ocean
This islands of the Arctic Ocean can be classified by the country that controls the territory. Canada *Arctic Archipelago **Queen Elizabeth Islands ***Axel Heiberg Island ***Ellesmere Island ***Devon Island *** Melville Island **Baffin Island **Banks Island **Victoria Island *Hans Island (shared with Denmark) *Herschel Island (in the Beaufort Sea, part of the Yukon) Denmark *Aasiaat Archipelago *Clavering Island * Geographical Society Island *Kaffeklubben Island *Milne Land * Naresland *Qeqertarsuaq (Disko Island) *Shannon Island *Traill Island *Ymer Island *Hans Island (shared with Canada) Iceland * Bjarnarey * Drangey * Eldey * Engey * Flatey, Breiðafjörður * Flatey, Skjálfandi * Grímsey * Heimaey * Hrísey * Hvalbakur * Kolbeinsey * Málmey * Papey * Surtsey * Viðey * Vigur * Æðey Norway * Bear Island *Jan Mayen *Svalbard Archipelago: **Barentsøya *** Alekseevøya ***Kükenthaløya **Edgeøya ***Halvmåneøya ***Ryke Yseøyane ***Thousand Islands *** Zeiløyane ** ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arctic Ocean
The Arctic Ocean is the smallest and shallowest of the world's five major oceans. It spans an area of approximately and is known as the coldest of all the oceans. The International Hydrographic Organization (IHO) recognizes it as an ocean, although some oceanographers call it the Arctic Mediterranean Sea. It has been described approximately as an estuary of the Atlantic Ocean. It is also seen as the northernmost part of the all-encompassing World Ocean. The Arctic Ocean includes the North Pole region in the middle of the Northern Hemisphere and extends south to about 60°N. The Arctic Ocean is surrounded by Eurasia and North America, and the borders follow topographic features: the Bering Strait on the Pacific side and the Greenland Scotland Ridge on the Atlantic side. It is mostly covered by sea ice throughout the year and almost completely in winter. The Arctic Ocean's surface temperature and salinity vary seasonally as the ice cover melts and freezes; its salinity is t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Circumpolar Peoples
Circumpolar peoples and Arctic peoples are umbrella terms for the various Indigenous peoples of the Arctic. Prehistory The earliest inhabitants of North America's central and eastern Arctic are referred to as the Arctic small tool tradition (AST) and existed c. 2500 BC. AST consisted of several Paleo-Eskimo cultures, including the Independence cultures and Pre-Dorset culture.Gibbon, pp. 28–31 The Dorset culture (Inuktitut: ''Tuniit'' or ''Tunit'') refers to the next inhabitants of central and eastern Arctic. The Dorset culture evolved because of technological and economic changes during the period of 1050–550 BC. With the exception of the Quebec/Labrador peninsula, the Dorset culture vanished around 1500 AD. Dorset/Thule culture transition dates around the 9th–10th centuries. Scientists theorize that there may have been cross-contact of the two cultures with sharing of technology, such as fashioning harpoon heads, or the Thule may have found Dorset remnants and adapted the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antarctic Circumpolar Current
The Antarctic Circumpolar Current (ACC) is an ocean current that flows clockwise (as seen from the South Pole) from west to east around Antarctica. An alternative name for the ACC is the West Wind Drift. The ACC is the dominant circulation feature of the Southern Ocean and has a mean transport estimated at 100–150 Sverdrups (Sv, million m3/s), or possibly even higher, making it the largest ocean current. The current is circumpolar due to the lack of any landmass connecting with Antarctica and this keeps warm ocean waters away from Antarctica, enabling that continent to maintain its huge ice sheet. Associated with the Circumpolar Current is the Antarctic Convergence, where the cold Antarctic waters meet the warmer waters of the subantarctic, creating a zone of upwelling nutrients. These nurture high levels of phytoplankton with associated copepods and krill, and resultant foodchains supporting fish, whales, seals, penguins, albatrosses, and a wealth of other species. The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Subarctic
The subarctic zone is a region in the Northern Hemisphere immediately south of the true Arctic, north of humid continental regions and covering much of Alaska, Canada, Iceland, the north of Scandinavia, Siberia, and the Cairngorms. Generally, subarctic regions fall between 50°N and 70°N latitude, depending on local climates. Precipitation is usually low, and vegetation is characteristic of the taiga. Daylight at these latitudes is quite extreme between summer and winter due to its high latitude. Near the summer solstice for instance, subarctic regions can experience an all-night period of either civil, nautical, or astronomical twilight (or in the northern reaches full daylight), but without true night, since the sun never dips more than 18 degrees below the horizon. Noctilucent clouds are best observed within this range of latitude. Climate and soils Subarctic temperatures are above for at least one and at most three months of the year. Precipitation tends to be low du ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arctic Circle
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. 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. The position of the Arctic Circle is not fixed and currently runs north of the Equator. Its latitude depends on the Earth's axial tilt, which fluctuates within a margin of more than 2° over a 41,000-year period, o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
