Arctic, the northernmost area of the earth, centered on the North Pole. The arctic regions are not coextensive with the area enclosed by the Arctic Circle (lat. 66°30′N) but are usually defined by the irregular and shifting 50°C (10°C) July isotherm that closely corresponds to the northern limit of tree growth and that varies both N and S of the Arctic Circle. The regions therefore include the Arctic Ocean; the northern reaches of Canada, Alaska, Russia, Norway, and the Atlantic Ocean; Svalbard; most of Iceland; Greenland; and the Bering Sea.
The Columbia Electronic Encyclopedia, 6th ed. Copyright © 2012, Columbia University Press. All rights reserved.
Sections in this article:
- History of Exploration
- Natural Resources
- Flora and Fauna
See more Encyclopedia articles on: Arctic Physical Geography