During this week, part of California has been devastating by a high number of fires. In particular the area burnt down is the Ventura County, extending the south part of the state.
The RGB image below has been captured on 05 December 2017 by Sentinel-2B and shows the area affected by the fires.
In this case, as often happen, the fires have been maintained by dry winds. For this specific event, Santa Ana winds in combination also with dry vegetation made the situation worse.
The image below is a zoom of the previous image using a different composite of Sentinel-2 bands. For this image the Swir/Nir/Red band (12, 8A, 4) have been used.
The SWIR spectral regions provide indeed high burned-unburned discrimination. It is possible to observe that the dark red highlights the regions where the fires have been already passed, whereas the bright red represents the areas where the fires are still active.
Data: • Sentinel-2 level C-1 products downloaded from the Sentinel Scientific Data Hub: https://scihub.copernicus.eu/dhus/#/home