Arid
（重定向自Aridness）
A region is arid when it is characterized by a severe lack of available water, to the extent of hindering or preventing the growth and development of plant and animal life. Environments subject to arid climates tend to lack vegetation and are called xeric or desertic. Most "arid" climates surround the equator; these places include most of Africa and parts of South America, Central America and Australia.