Hindcasting extreme events: The occurrence and expression of damaging floods and landslides in southern Italy

Extreme rainstorm events across the Mediterranean have caused significant loss of life and damage to property and livelihoods. Italy is particularly vulnerable to natural hazards with recent events such as the 1996 floods in Versilia and the 1998 mass-movement failures at Sarno causing the deaths of 174 people. We have analysed 50 years of rainfall records to hindcast extreme rainstorms that have affected the eastern Basilicata region of southern Italy. Historical and archive data of individual floods and landslides have been compared with their antecedent rainfall conditions in order to characterize the nature of events that cause damage to society and infrastructure. Analysis of extreme-event frequency shows a decreasing annual trend related to changes in regional climate conditions in the western and central Mediterranean driven by changes in the strength of the North Atlantic Oscillation. Land-degradation problems associated with floods and landslides are decreasing due to a drier winter climate coupled with improved hazard mitigation. Copyright (c) 2006 John Wiley & Sons, Ltd.