Temporal analysis (1940 2010) of rainfall aggressiveness in the Iberian Peninsula basins L. García-Barrón 1* , J.M. Camarillo 2 , J. Morales 3 , A. Sousa 3 1 Departamento de Física Aplicada II, Universidad de Sevilla, 41012 Sevilla, Spain 2 Departamento de Geografía Física, Universidad de Sevilla, 41004 Sevilla, Spain 3 Departamento de Biología Vegetal y Ecología, Universidad de Sevilla, 41012 Sevilla, Spain ABSTRACT Rainfall aggressiveness causes environmental impacts and it is related to several natural hazards. Therefore, this parameter has been chosen as an environmental indicator. The present study is based on the monthly estimated rainfall using the Precipitation Runoff Integrated Model (SIMPA) for each Spanish hydrographic basin from 1940 to 2010. The main aim is to analyse temporal irregularity of rainfall aggressiveness in large geographic areas and to extract spatio-temporal patterns. For each year the rainfall aggressiveness was calculated using the Modified Fournier Index (I FM ) and Oliver´s Index of Precipitation Concentration (I PC ). The temporal variability of the annual series of these indices was analysed for each zone delimited. The results obtained made it possible to characterize the rainfall aggressiveness in the Iberian Peninsula and to determine its evolution over the past decades. They also reveal that the general pattern of the rainfall aggressiveness is determined by the dual effect of latitude (north south) and longitude (east west) as a result of the different maritime influences of the Atlantic and the Mediterranean watersheds. *Revised Manuscript with no changes marked Click here to view linked References