Arid Diagonal

Map showing Köppens climate classification for South America. The arid diagonal can be seen in the form of the almost contiguous zone of BWh and BWk climate (red and pink on this map) running from Ecuador to Southern Patagonia.

The Arid Diagonal (Spanish: diagonal árida/arreica) is a contiguous zone of arid and semi-arid climate that traverses South America from coastal Peru in the Northwest to Argentine Patagonia in the Southeast, including large swathes of Bolivia and Chile.[1] The Arid Diagonal encompasses a number of deserts, for example Sechura, Atacama, Monte and the Patagonian Desert.

The Arid Diagonal acts to isolate the temperate and subtropical forests of Chile and southern Argentina from other forests of South America.[2] Together with the Quaternary glaciations in the Southern Andes, the diagonal has controlled the distribution of vegetation throughout Chile and Argentina.[3]

The concept of a South American Arid Diagonal was first coined by French geographer Emmanuel de Martonne in his 1935 work Problème des régions arides Sud-Américaines.[4] However, few works dealing with the Arid Diagonal mention this foundational text.[4] The original Arid Diagonal of de Martonne went from Antofagasta in northern Chile to the northern coast of Argentine Patagonia.[4] However, other authors like Margarita González Loyarte (1995) later extended it to the coast of northern Peru.[4]

  1. ^ Bruniard, Enrique D. (1982). "La diagonal árida Argentina: un límite climático real". Revista Geográfica (in Spanish): 5–20.
  2. ^ Villagrán, Carolina; Hinojosa, Luis Felipe (1997). "Historia de los bosques del sur de Sudamérica, II: Análisis fitogeográfico". Revista Chilena de Historia Natural (in Spanish). 70: 241–267.
  3. ^ Cite error: The named reference VillagranHinojosa2005 was invoked but never defined (see the help page).
  4. ^ a b c d Abraham, Elena María; Rodríguez, María Daniela; Rubio, María Clara; Guida-Johnson, Bárbara; Gomez, Laura; Rubio, Cecilia (2020-01-08). "Disentangling the concept of "South American Arid Diagonal"". Journal of Arid Environments. 175: 104089. Bibcode:2020JArEn.175j4089A. doi:10.1016/j.jaridenv.2019.104089. S2CID 213655544.