Design of a susceptibility index for fire risk monitoring

In this letter, we present a new remote sensing fire susceptibility index (FSI) based on the physical concept of heat energy of preignition. This physical basis allows computations of ignition probabilities and comparisons of fire risk across ecoregions. The index has the flexibility to be localized to a vegetation type or ecoregion for improved performance. The computation of the index requires inputs of fuel temperature and fuel moisture content, both of which can be estimated using remote sensing techniques. While Moderate Resolution Imaging Spectrometer data for surface temperature are used as a proxy for fuel temperature, live fuel moisture is estimated by a linear regression technique utilizing the correlation between model-based live fuel moisture measurements at automated ground stations and the ratio of normalized difference vegetation index and surface temperature. FSIs are computed for the Georgia region during the spring and summer months of 2004 and validated with the well-tested fire potential index (FPI). Results show a good agreement between FSI and FPI. It suggests that FSI can be a good estimator of fire risk.