Earth's polar regions are the areas of the globe surrounding the
poles also known as
frigid zones. The
North Pole and
South Pole being the centers, these regions are dominated by the
polar ice caps, resting respectively on the
Arctic Ocean and the continent of
Antarctica. Polar
sea ice is currently diminishing, possibly as a result of
anthropogenic global warming.
[citation needed]The Arctic has numerous definitions, including the region north of the Arctic Circle (66-33N), or the region north of 60 degrees north latitude, or the region from the North Pole south to the timberline.
The Antarctic is usually defined as south of 60 degrees south latitude, or the continent of Antarctica. The 1959 Antarctic Treaty uses the former definition.
Polar regions receive less intensive solar radiation because the sun's energy arrives at an oblique angle, spreading over a larger area, and also travels a longer distance through the Earth's atmosphere in which it may be absorbed, scattered or reflected, which is the same thing that causes winters to be colder than the rest of the year in temperate areas.
