INVESTIGATING THE CHANGES IN EXTERNE RAINFALL SERIES RECORDED IN AN URBANISED AREA

Investigation and quantity changes in the rainfall regime of the metropolitan area of Palermo (Sicilia) characterised by increasing strong urbanisation. Rainfall data has been made with eight rain gauges. A preliminary analysis made on the annual total rainfall depths showed a global reduction of total annual rainfall. The analysis with two different trends in the extreme rainfall series has been performed by estimating the maximum rainfall depth corresponding to a fixed return period. The analysis of all series indicates a global reduction of rainfall intensities both for internal and external series.