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Arid regions of the Western United States as mapped in 1893 1893 Arid regions of the western united states.jpg
Arid regions of the Western United States as mapped in 1893

A region is arid when it severely lacks available water, to the extent of hindering or preventing the growth and development of plant and animal life. Regions with arid climates tend to lack vegetation and are called xeric or desertic. Most arid climates straddle the Equator; these regions include parts of Africa, Asia, South America, North America, and Australia.


Change over time

The distribution of aridity at any time is largely the result of the general circulation of the atmosphere. The latter does change significantly over time through climate change. For example, temperature increase by 1.5–2.1 percent across the Nile Basin over the next 30–40 years could change the region from semi-arid to arid, significantly reducing the land usable for agriculture. In addition, changes in land use can increase demands on soil water and thereby increase aridity. [1]

See also

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  1. United States Geological Survey (May 24, 2017). "Increasing Aridity and Land-use Overlap Have Potential to Cause Social and Economic Conflict in Dryland Areas" . Retrieved July 29, 2022.