Lably
Skip to content

Arctic

Polar region of the Earth's northern hemisphere

  • 13 min read
  • 10 chapters

Related on Lably

Through Polar regions and Earth

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 ἀρκτικός arktikos "near the Bear, northern" and from the word ἄρκτος 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 10 °C (50 °F); the northernmost tree line roughly follows the isotherm at the boundary of this region.

Sign in to keep reading

9 more chapters are free with a Lably account.

More in Continents and regions