System analysis of weather fire danger in predicting large fires in Siberian forests

The prediction results of large-scale forest fire development are given for Siberia. To evaluate the fire risks, the Canadian Forest Fire Weather Index System (CFFWIS) and the Russian moisture indices (MI1 and MI2) were compared on the basis of the data of a network of meteorological stations as input weather parameters. Parameters of active fires were detected daily from the NOAA satellite data for the period of 1996–2008. To determine the length of the fire danger season, the snow cover fractions from Terra/MODIS data (2001–2008) were used. The features of fire development on territories with different types of flammable fuel are considered. The statistical analysis of the areas and number of fires typical of each vegetation class is made with the use of the GLC2000 vegetation map. A positive correlation (∼0.45, p < 0.05) between the cumulative area of local fires and the MI1 and Canadian BUI and DMC indices is revealed. The Canadian ISI and FWI indices describe best the diurnal dynamics of fire areas. The above correlations are higher (∼0.62, p < 0.05) when we select the fires larger than 2000–10000 ha in size for the forested areas. Other cases point to the lack of a linear relation between the fire area and the values of all indices, because the fire spread depends on many natural and anthropogenic factors.