Bill’s heating up and chilling out in the “Deserts” episode.
About 20% of the Earth is a desert. Deserts are places that get very little precipitation (rain or snow) each year, and that makes them extremely dry. Deserts cover big areas of land. The biggest desert, the Sahara, extends from North Africa to Southwest Asia and is 13 times the size of Texas. Some parts of the Sahara get as little as 2 millimeters (0.08 inches) of water a year.
Since water is scarce, animals that live in deserts have ways to find, save, and use very little of this precious liquid. Camels store fat in their humps. When they burn the fat for energy, the make water for their bodies. Cacti have wide and shallow roots so that when it does rain, they drink up as much water as possible.
Not all deserts are dry, dusty, and hot. The Antarctic is also a desert. It may be cold, but, just like the Sahara, the Antarctic doesn’t get very much precipitation.
Science is never dry with Bill Nye the Science Guy.