Spatio-Temporal Analysis of the Relationship between South American Precipitation Extremes and the El Niño Southern Oscillation

Understanding the spatial variability of precipitation extremes and their relationship to the El Nino Southern oscillation (ENSO) phenomenon is a valuable task since precipitation extremes are often related to natural disasters such as flooding. This study aims to evaluate and provide insight into the relationship between ENSO and the parameters of the extreme value distributions over South America for precipitation data between 1978-2004. The relationship between these values, as described by the global and local Moran I statistics, has been analysed against the Southern Oscillation Index (SOI), which is generally used as a mean sure of the intensity of ENSO at a given time. Through analysis, we are the first to show increased spatial dependence of the parameters of the extreme value distributions between regions during strong El Nino periods.