The effect of savanna fires on SAR backscatter in northern Australia

This paper investigates the potential for utilizing multi-frequency, quad-polarized Synthetic Aperture Radar (SAR) for delineation of fire scars in the tropical savannas of northern Australia. Fire regimes and regional land management in the study area are contentious issues for the multiple stakeholders. Thus, the ability to accurately map fire scars and assess impacts on the mosaic of vegetation community types is crucial for effective landscape management. In this study identification of a fire sear resulting from a late dry season fire was assessed using TopSAR data. The assessment was achieved through comparison with optical datasets acquired both pre-burn and post-burn. By examining five representative vegetation communities, it was concluded that only C-band SAR data were affected sufficiently by fire in this environment to detect and map fire scars. Despite the intensity of the fire event, the resistance of vegetation communities to fire damage resulted in insignificant changes to the L- and P-band SAR data. Further investigation is required to determine if this behaviour can be exploited to improve the above-ground woody biomass mapping currently reliant on optical data.