Nowadays Earth observation satellites, in particular Landsat, provide a valuable help to forest managers in postfire
operations; being the base of post-fire damage maps that enable to analyze fire impacts and to develop
vegetation recovery plans. Sentinel-2A MultiSpectral Instrument (MSI) records data in similar spectral wavelengths
that Landsat 8 Operational Land Imager (OLI), and has higher spatial and temporal resolutions. This
work compares two types of satellite-based maps for evaluating fire damage in a large wildfire (around 8000 ha)
located in Sierra de Gata (central-western Spain) on 6–11 August 2015. 1) burn severity maps based exclusively
on Landsat data; specifically, on differenced Normalized Burn Ratio (dNBR) and on its relative versions (Relative
dNBR, RdNBR, and Relativized Burn Ratio, RBR) and 2) burn severity maps based on the same indexes but
combining pre-fire data from Landsat 8 OLI with post-fire data from Sentinel-2A MSI data. Combination of both
Landsat and Sentinel-2 data might reduce the time elapsed since forest fire to the availability of an initial fire
damage map. Interpretation of ortho-photograph Pléiades 1 B data (1:10,000) provided us the ground reference
data to measure the accuracy of both burn severity maps. Results showed that Landsat based burn severity maps
presented an adequate assessment of the damage grade (κ statistic =0.80) and its spatial distribution in wildfire
emergency response. Further using both Landsat and Sentinel-2 MSI data the accuracy of burn severity maps,
though slightly lower (κ statistic =0.70) showed an adequate level for be used by forest managers
