The five main latitude regions of the Earth's surface comprise geographical zones, divided by the major circles of latitude. The differences between them relate to climate, and the behaviour of the Sun. They are as follows:
- The North Frigid Zone, north of the Arctic Circle
- The North Temperate Zone, between the Arctic Circle and the Tropic of Cancer
- The Torrid Zone, between the Tropical Circles
- The South Temperate Zone, between the Tropic of Capricorn and the Antarctic Circle
- The South Frigid Zone, south of the Antarctic Circle In the Torrid Zone, also known as the Tropics, the Sun is directly overhead at least once during the year. In the Northern Hemisphere, the overhead Sun moves north from the Equator until it reaches 23.5 degrees North (Tropic of Cancer) at the June solstice, after which it moves back south to the Equator. In the Southern Hemisphere, the overhead Sun moves south from the Equator until reaches 23.5 degrees South (Tropic of Capricorn) at the December solstice, after which it moves back north to the Equator. In the two Temperate Zones, consisting of the tepid latitudes, the Sun is never directly overhead, and the climate is mild, generally ranging from warm to cool. The four annual seasons, Spring, Summer, Autumn and Winter, occur in these areas. The two Frigid Zones, or polar regions, experience the midnight sun and the polar night for part of the year - at the edge of the zone there is one day at the winter solstice when the Sun does not rise or set for 24 hours, while in the centre of the zone (the pole), the day is literally one year long, with six months of daylight and six months of night. The Frigid Zones are the coldest parts of the earth, and are generally covered with ice and snow. The North Frigid Zone (the Arctic) includes the northern parts of Canada, Alaska, Greenland, Scandinavia, Russia, and the Arctic Ocean in between them. The South Frigid Zone (the Antarctic) is filled by the continent of Antarctica; the next closest significant land to this zone is the southern tip of Chile and Argentina, followed by the South Island of New Zealand and then Tasmania.
