Burned areas detection and Fire Weather Index. A study case in NW Italy

The study was carried out in NW-Italy and focused on the detection of burned areas and the evaluation of the fire danger. The first aim was to extract the areas affected by fire in a semiautomatic way from Landsat images; the second one to evaluate the use of the Fire Weather Index (FWI) for defining the fire danger, as the weather factors influence a lot the fire, mainly their ignition and propagation. Automatic Burned Area Detection Software (ABAMS) was used for the detection and the best indexes to be utilized in its two phases were chosen. The burned areas and the FWI daily data were studied considering a period of four years. The U Mann-Whitney analysis was applied to verify the relationships between burned areas and weather indexes. The results seem to show that the FWI and the Drought Code (DC) can explain well the fires event and their extension. A first definition of the indexes thresholds that could be used to discriminate among classes of danger was made. The study highlights the connection of fires frequency and extension with the weather conditions, confirming that these factors, combined in a meteorological index, can be useful to estimate the fire danger