Climate

The Earth is divided into five climatic zones: two Frigid Zones, two Temperate Zones and one Torrid Zone.

These zones have precise astronomical definitions based on the angle of tilt of the Earth's axis (23°) relative to the plane of the Earth's orbit.

Coldest are the North and South Frigid Zones, lying between the poles and the Arctic and Antarctic Circles (each of which is at an angle of 23° to the Earth's axis).

Between the Frigid Zones and the Tropics of Cancer and Capricorn (each of which is at an angle of 23° to the plane of the equa¬tor) are the Temperate Zones.

The hottest region, lying between the Tropics, on both sides of the equator, is the Torrid Zone.