Simulazione del comportamento di grandi incendi storici in ambiente mediterraneo mediante il simulatore FARSITE

Wildfires are a problem in the Mediterranean area, due to the weather characterized by hot and dry summers. In many fire regimes the link between number and size of fires shows how a small number of events is responsible for most of the area burned and most of the damage (both economic and environmental) frequently associated with loss of human lives. These kind of fires usually tend to occur under specific and relatively uncommon meteorological conditions, typically involving combinations of high temperature, low relative humidity, prolonged drought and strong winds. They display a fire behaviour pattern (like crowing and spotting) not observed in small fires. For this reason fighting them is very difficult.The aims of this thesis are: to analyse Sardinia fire regime in the period 2005-2012; to evaluate FARSITE simulator for the large fires observed in Sardinia; to quantify fire’s potential behaviour in relation with environmental condition observed during the wildfires and, finally, analyse environmental conditions effect on the behaviour and fire spread.The results evidenced that FARSITE gave good results for the past large fires that usually occur in extreme weather conditions, in days in which there were more ignitions at the same time and in different sites. We found a great range of fire behaviours, as rate of spread, fire line intensity and flame length varied with the fuel model types. Also important in fire behaviour was the variability in topography.