C-Band SAR Backscatter Evaluation of 2008 Gallipoli Forest Fire

The ability to quantify forest fire severity levels is of great importance for fire monitoring, management, and research. Optical observations have been found to be well suited to estimate the impact of fire on the forest canopy. In this letter, C-band VV polarization synthetic aperture radar (SAR) backscatter response to a forest fire was evaluated against burn severity estimated by the Landsat difference Normalized Burn Ratio (dNBR) products. It was observed that the difference between pre- and postfire backscatters (ratios in power) increased with the dNBR index. Temporal evaluation of backscatter change with respect to various pre- and postfire conditions showed a noticeable sensitivity on the state of a burned stand and its local fire impact levels in wet conditions but, to a lesser degree, in dry conditions. A SAR approach that combines pre- and postfire backscattering could be used to quantify the fire impacts if the effects induced by geometry, weather, and other human activities are accounted for in the analysis.