Advances in Geosciences www.adv-geosci.net 1680-7340 1680-7359 22 4th EGU Alexander von Humboldt Conference "The Andes: Challenge for Geosciences" 2009 10.5194/adgeo-22-3-2009 http://www.adv-geosci.net/22/3/2009/ http://www.adv-geosci.net/22/3/2009/adgeo-22-3-2009.html http://www.adv-geosci.net/22/3/2009/adgeo-22-3-2009.pdf 3 11 2009-10-13 The Andes climate and weather R. D. Garreaud rgarreau@dgf.uchile.cl Department of Geophysics, Universidad de Chile, Santiago, Chile This paper documents the main features of the weather, climate and climate variability over Andes cordillera in South America on the basis of instrumental observations. We first provide a basic physical understanding of the mean annual cycle of the atmospheric circulation and precipitation and over the Andes and adjacent lowlands. 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