Map of the Atacama Desert: the area most commonly defined as Atacama is in yellow. In orange are the outlying arid areas of the southern Chala, Altiplano, Puna de Atacama, and Norte Chico. The vertical extent of the satellite photo is approximately 2,600 km, encompassing the desert and surrounding regions.
The Atacama Desert (Spanish: Desierto de Atacama) is a desert plateau located on the Pacific coast of South America, in the north of Chile. Stretching over a 1,600-kilometre-long (1,000-mile) strip of land west of the Andes Mountains, it covers an area of 105,000 km2 (41,000 sq mi),[2] which increases to 128,000 km2 (49,000 sq mi) if the barren lower slopes of the Andes are included.[3]
The Atacama Desert is the driest nonpolar desert in the world, and the second driest overall, behind some specific spots within the McMurdo Dry Valleys.[4][5][6][7] It is the only true desert to receive less precipitation than polar deserts, and the largest fog desert in the world. The area has been used as an experimentation site for Mars expedition simulations due to its similarities to the Martian environment.
The constant temperature inversion caused by the cool north-flowing Humboldt ocean current and the strong Pacific anticyclone contribute to the extreme aridity of the desert.[8] The most arid region of the Atacama Desert is situated between two mountain chains, the Andes and the Chilean Coast Range, which are high enough to prevent moisture advection from either the Pacific or the Atlantic Ocean, creating a two-sided rain shadow effect.[9]
^Eric Dinerstein, David Olson, et al. (2017). An Ecoregion-Based Approach to Protecting Half the Terrestrial Realm, BioScience, Volume 67, Issue 6, June 2017, Pages 534–545; Supplemental material 2 table S1b. [1]
^Rundel, P.W.; Villagra, P.E.; et al. (2007). "Arid and Semi-Arid Ecosystems". In Veblen, Thomas T.; Young, Kenneth R.; Orme, Anthony R. (eds.). Physical Geography of South America. Oxford University Press. pp. 158–183.