The Advanced Rapid Imaging and Analysis (ARIA) team at NASA's Jet Propulsion Laboratory in Pasadena, California, and Caltech, also in Pasadena, created this Damage Proxy Map (DPM) depicting areas in Northern California that are likely damaged (shown by red and yellow pixels) as a result of wildfires. The map is derived from synthetic aperture radar (SAR) images from the Copernicus Sentinel-1 satellites, operated by the European Space Agency (ESA). The images were taken before (Sep. 27, 2017 7PM) and after (Oct. 9, 2017 7PM, both Pacific Time) the onset of the fires.
The map covers an area of 250 by 170 kilometers, shown by the large red polygon. Each pixel measures about 30 meters across. The color variation from yellow to red indicates increasingly more significant ground surface change. Preliminary validation was done by comparing to optical satellite imagery by the DigitalGlobe. This damage proxy map should be used as guidance to identify damaged areas, and may be less reliable over vegetated areas. Sentinel-1 data were accessed through the Copernicus Open Access Hub. The image contains modified Copernicus Sentinel data (2017), processed by ESA and analyzed by the NASA-JPL/Caltech ARIA team. This research was carried out at JPL under a contract with NASA.