Arid regions of the Western United States as mapped in 1893
Aridity is the condition of geographical regions which make up approximately 43% of total global available land area, characterized by low annual precipitation, increased temperatures, and limited water availability.[1][2][3][4] These areas tend to fall upon degraded soils, and their health and functioning are key necessities of regulating ecosystems’ atmospheric components.[5][3]
The distribution of aridity at any time is largely the result of the general circulation of theatmosphere. The latter does change significantly over time throughclimate change. For example, temperature increase by 1.5–2.1 percent across theNile Basin over the next 30–40 years could change the region fromsemi-arid to arid, significantly reducing the land usable foragriculture. In addition, changes in land use can increase demands on soil water and thereby increase aridity.[6]
A December 2024 report from theUNCCD concluded that more than three-quarters of the Earth's land "has become permanently dryer in recent decades", that "drier climates now affecting vast regions across the globe will not return to how they were", and that a quarter of the global population lives in expanding drylands.[7]
^Dunkerley, David, (2020),The Ecohydrology of Desert Environments: What Makes it Distinctive?, Encyclopedia of the World's Biomes,Elsevier, Pages 23-35, ISBN 9780128160978,https://doi.org/10.1016/B978-0-12-409548-9.11803-22.
^FAO. Elaboración de un Programa Mundial Sobre Agricultura Sostenible en Zonas Áridas en Colaboración con el Marco Mundial Sobre la Escasez de Agua en la Agricultura en un Clima Cambiante.http://www.fao.org/3/nd412es/nd412es.pdf
^abPerez-Aguilar, L. Y., Plata-Rocha, W., Monjardin-Armenta, S. A., Franco-Ochoa, C., & Zambrano-Medina, Y. G. (2021). The Identification and Classification of Arid Zones through Multicriteria Evaluation and Geographic Information Systems—Case Study: Arid Regions of Northwest Mexico.ISPRS International Journal of Geo-Information,10(11), 720.https://doi.org/10.3390/ijgi10110720
^Quichimbo, E.A.; Singer, M.B.; Cuthbert, M.O. Characterising Groundwater-Surface Water Interactions in Idealised Ephemeral Stream Systems.Hydrol. Process. 2020,34, 3792–3806.https://doi.org/10.1002/hyp.13847
Griffiths, J. F. (1985) 'Climatology', Chapter 2 inHandbook of Applied Meteorology, Edited by David D. Houghton, John Wiley and Sons,ISBN0-471-08404-2.
Durrenberger, R. W. (1987) 'Arid Climates', article inThe Encyclopedia of Climatology, p. 92–101, Edited by J. E. Oliver and R. W. Fairbridge, Van Nostrand Reinhold Company, New York,ISBN0-87933-009-0.
Stadler, S. J (1987) 'Aridity Indexes', article inThe Encyclopedia of Climatology, p. 102–107, Edited by J. E. Oliver and R. W. Fairbridge, Van Nostrand Reinhold Company, New York,ISBN0-87933-009-0.
