Statistical Analysis of Extreme Events of Precipitation in Central and South Continental Chile

Abstract

In this paper the spatial distribution of extreme precipitation risk between the fifth and eleventh regions of the Chilean mainland is studied. In order to achieve that, probable maximum values of daily precipitation for different return periods are calculated, analyzing the maximum amounts of rainfall in 24 hours in 46 rainfall stations with records between 1980 and 2010. The methodological approach has been the adjustment of the data by means of different probability laws, especially Gumbel Max and Weibull, and the calculation of maximum values and returns periods. The results show a large spatial variability of maximum precipitations, the highest ones being located in the Andean foothills, decreasing gradually to pass the Intermediate depression and increasing again in the Costa range. The highest estimated daily precipitation occur at Valparaíso, Maule and Bío-Bío regions, with values equal to or greater than 200 mm in 50 years.