Hemispheric University

Universidad Austral

Research Project Title

Offered Collaboration Project on “Climate Change”: Extreme precipitation events in South America

Research Project Description

The distribution of rainfall and its occurrence in South America is strongly determined by the low level (tropospheric) atmospheric circulation and by the presence of the Andes mountain range.


The humid air that comes from the Atlantic Ocean enters the continent in northern Brazil and continues westward over the Amazon basin and the eastern Andes.


The understanding of tectonic influence to force climate and surface processes is closely related to the knowledge of orography and the development of mountain belts and their distribution. The Andes region has an asymmetric distribution of rainfall due to the altitudes of the mountain range. Precipitation mechanisms in turn affect its erosion. Extreme rain is one of the main factors that control the hydrological cycle of South America, causing landslides and flash floods along the eastern side of the Andes. Floods in the Amazon due to river overflow are related to rainfall anomalies, as well as when the rain occurs. The direction of low level atmospheric air drives the emergence of these extreme situations.


The relief of the mountain range and its relationship with orographic rain can result in different landscapes, where the average rainfall in geological time scale is one of the key factors in the development of the Andes Mountains. In addition, this precipitation can produce spatial correlations between rapid tectonic elevation and heavy rainfall, even in the absence of erosive influence. In the case of the Andes mountain range, the extremely asymmetric distribution of rainfall due to high topography strongly affects erosion and sediment deposition.


A key concept regarding the interactions between orography and climatic interactions is based on the idea that, in a region with similar geological conditions, humid weather produces a slower erosion than in dry conditions. Severe socioeconomic effects are present throughout the Andes, as a result of downstream flooding and landslides caused by heavy rainfall.


A study and identification of the main temporal space patterns of extreme precipitation in South America and their relationship with the phases of the ENSO (El Niño Southern Oscillation) climatic phenomenon are proposed based on the analysis of: 1) water vapor data obtained by different constellations of satellites during the last decades and 2) the corresponding data of reanalysis of climate monitoring and atmospheric parameters on a global scale.

Research Project Academic Contact

Alejandro De La Torre, Director