Análisis espacial y temporal de las lluvias extremas en Catalunya. Modelización y clasificación objetiva

Abstract

The main objective of this thesis is the study of the extreme rainfall in Catalonia, its spatial and time organization showing the contribution of the different meteorological scales to the rain precipitation process, and to obtain the extreme rainfall spatial distribution over the Catalonian territory using objective analysis techniques. Relationship between the maximum rain intensities registered in Barcelona in the period 1927 - 2001, their duration and their frequency has been analyzed. A revision of the Intensity-Duration-Frequency (IDF) curves for Barcelona and their generalized equation have been obtained. The extraordinarily intense rainfall events registered by a Jardí gauge located in the Fabra Observatory of Barcelona between 1927 and 1992, and those registered between 1994 and 2001 by the urban pluviometric network supported by CLABSA in this city, have been characterized and objectively classified according to their meteorological scale. A rain intensity index reflecting the contribution to the origin of the rainfall events of local, mid and synoptic scale processes has been proposed and calculated. This index is very useful in order to objectively ponder the extreme and severe behaviors of the rainfall events in our zone. An objective analysis method has been applied to obtain the spatial distribution of the maximum daily rainfall in Catalonia, with return periods between 2 and 500 years and a resolution of 1 km x 1 km. The probable maximum precipitation (PMP) in 24 hours and its spatial distribution over Catalonia, with a resolution 1 km x 1 km, have been calculated using its statistical estimation method and objective spatial analysis techniques. The PMP in Barcelona for lower durations has been estimated also. KEY WORDS: Maximum rainfall rate, extreme rainfall, IDF curves, meteorological scales, maximum daily precipitation, extreme distributions, spatial rainfall distribution, objective analysis, probable maximum precipitation. "