Related topics: sea ice · climate change · ice · climate · global warming

Researchers confirm that narwhals and belugas can interbreed

A team of University of Copenhagen researchers has compiled the first and only evidence that narwhals and beluga whales can breed successfully. DNA and stable isotope analysis of an anomalous skull from the Natural History ...

100-year-old physics model replicates modern Arctic ice melt

The Arctic is melting faster than we thought it would. In fact, Arctic ice extent is at a record low. When that happens—when a natural system behaves differently than scientists expect—it's time to take another look at ...

Why Cry for the Cryosphere?

The headline is actually a sentence that comes toward the end of Vanishing Ice, a new book that answers the question in encyclopedic detail. For those unfamiliar with the term, the cryosphere is the earth's natural ice ...

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Arctic

The 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.

This text uses material from Wikipedia, licensed under CC BY-SA