Arctic
hideThe Arctic (pronounced /ˈɑrktɪk/ or /ˈɑrtɪk/) 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 αρκτικός (arktikos), "near the Bear, arctic, northern" and that from the word άρκτος (arktos), which means bear. The name refers either to the constellation Ursa Major, the "Great Bear", which is prominent in the northern portion of the celestial sphere, or to the constellation Ursa Minor, the "Little Bear", which contains Polaris, the Pole Star, also known as the North Star.[citation needed]
The Arctic region can be defined as the area north of the Arctic Circle (66° 33’N), which is the approximate limit of the midnight sun and the polar night. Alternatively, it can be defined as the region where the average temperature for the warmest month (July) is below 10 °C (50 °F); the northernmost tree line roughly follows the isotherm at the boundary of this region. 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.
Due to the poleward migration of the planet's isotherms (about 35 miles 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 spectacular result of Arctic shrinkage is sea ice loss. There is a large variance in predictions of Arctic sea ice loss, with models showing near-complete to complete loss in September from 2040 to some time well beyond 2100. About half of the analyzed models show near-complete to complete sea ice loss in September by the year 2100.
For more information about Arctic, read the full article at
Wikipedia.
This text uses material from Wikipedia and is available under the GNU Free Documentation License.
News tagged with arctic
Cuts in greenhouse gas emissions would save Arctic ice, reduce sea level rise
Space & Earth / Earth Sciences
Apr 14, 2009 |
4.6 / 5 (88) |
15
The threat of global warming can still be greatly diminished if nations cut emissions of heat-trapping greenhouse gases by 70 percent this century, according to a new analysis. While global temperatures would ...
Climate trouble may be bubbling up in far north
Aug 30, 2009 |
4.7 / 5 (77) |
27
(AP) -- Only a squawk from a sandhill crane broke the Arctic silence - and a low gurgle of bubbles, a watery whisper of trouble repeated in countless spots around the polar world.
New Arctic satellite data shows Arctic literally on thin ice
Space & Earth / Earth Sciences
Apr 06, 2009 |
4.5 / 5 (79) |
43
The latest data from NASA and the University of Colorado at Boulder's National Snow and Ice Data Center show the continuation of a decade-long trend of shrinking sea ice extent in the Arctic, including new ...
Global warming impacting Greenlanders' daily lives
Jul 09, 2009 |
4.5 / 5 (76) |
21
From his trawler that motors along the Nuuk fjord, fisherman Johannes Heilmann has watched helplessly in recent years as climate change takes its toll on Greenland.
Increasing Antarctic sea ice extent linked to the ozone hole
Space & Earth / Earth Sciences
Apr 21, 2009 |
4.4 / 5 (70) |
12
Increased growth in Antarctic sea ice during the past 30 years is a result of changing weather patterns caused by the ozone hole according to new research published this week (Thurs 23 April 2009).
New NASA Satellite Survey Reveals Dramatic Arctic Sea Ice Thinning
Space & Earth / Earth Sciences
Jul 07, 2009 |
4.7 / 5 (65) |
6
(PhysOrg.com) -- Arctic sea ice thinned dramatically between the winters of 2004 and 2008, with thin seasonal ice replacing thick older ice as the dominant type for the first time on record. The new results, ...
Ice-free Arctic Ocean possible in 30 years, not 90 as previously estimated
Space & Earth / Earth Sciences
Apr 02, 2009 |
4.4 / 5 (62) |
20
(PhysOrg.com) -- A nearly ice-free Arctic Ocean in the summer may happen three times sooner than scientists have estimated. New research says the Arctic might lose most of its ice cover in summer in as few ...
Arctic at warmest levels in 2,000 years or more
Space & Earth / Earth Sciences
Sep 03, 2009 |
4.3 / 5 (64) |
25
Arctic temperatures in the 1990s reached their warmest level of any decade in at least 2,000 years, new research indicates. The study, which incorporates geologic records and computer simulations, provides ...
Tipping elements remain a 'hot' issue
Space & Earth / Earth Sciences
Aug 24, 2009 |
4.5 / 5 (55) |
7
(PhysOrg.com) -- Research published by climate scientists at the University of East Anglia (UEA) has been named one of the most highly-cited in its field in the last two years.
Less ice in the Arctic Ocean 6000-7000 years ago
Space & Earth / Earth Sciences
Oct 20, 2008 |
4.7 / 5 (46) |
15
Recent mapping of a number of raised beach ridges on the north coast of Greenland suggests that the ice cover in the Arctic Ocean was greatly reduced some 6000-7000 years ago. The Arctic Ocean may have been periodically ice ...
Arctic ice on the verge of another all-time low
Space & Earth / Earth Sciences
Aug 28, 2008 |
3.6 / 5 (54) |
123
Following last summer's record minimum ice cover in the Arctic, current observations from ESA's Envisat satellite suggest that the extent of polar sea-ice may again shrink to a level very close to that of ...
British team trek to North Pole to measure sea ice
Space & Earth / Earth Sciences
Mar 01, 2009 |
4.7 / 5 (36) |
3
Three British explorers have set out on a 90-day skiing expedition to the North Pole, measuring sea ice thickness the whole way to find out exactly how fast it is disappearing, according to the Catlin Arctic ...
Scientists issue warning on future of central Arctic
Apr 17, 2009 |
4.2 / 5 (35) |
12
(PhysOrg.com) -- Scientists have warned that world leaders are in a race against time to make key decisions about the future of international co-operation in the Arctic.
Mystery mechanism drove global warming 55 million years ago
Space & Earth / Earth Sciences
Jul 13, 2009 |
4.3 / 5 (25) |
24
A runaway spurt of global warming 55 million years ago turned Earth into a hothouse but how this happened remains worryingly unclear, scientists said on Monday.
Arctic sea ice hits second-lowest extent, likely lowest volume
Space & Earth / Earth Sciences
Oct 02, 2008 |
2.8 / 5 (32) |
78
Arctic sea ice extent during the 2008 melt season dropped to the second-lowest level since satellite measurements began in 1979, reaching the lowest point in its annual cycle of melt and growth on Sept. 14, ...
