Skip to content
Search the Discovery Encyclopedia
-
Geography
The polar regions
Earth has two polar regions, around the North and South Poles. They are mirror opposites. The Arctic is an ocean almost surrounded by land, and much of it is covered by floating sea ice. The Antarctic is a continent, Antarctica, covered by a thick ice sheet and surrounded by the Southern Ocean. Both are cold because the Sun's light reaches them weakly and, in winter, hardly at all.
-
Geography
Climate zones
Geographers sort the world's climates into a few big groups called climate zones: tropical, dry, temperate, continental and polar, plus cold highland climates on mountains. A zone depends mostly on temperature and rain, which decide what plants can grow. How much sunlight a place gets, how near it is to the ocean, how high it is and the winds all help decide its zone.