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 including the Commonwealth of Dominica, that are likely damaged (shown by red and yellow pixels) as a result of Hurricane Maria (a Category 5 storm at landfall in Dominica on Sept. 18, 2017). 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 (March 27, 2017) and after (Sept. 23, 2017) the landfall of the storm.
The map covers the area within the large red polygon, which measures 53 by 106 miles (85 by 170 kilometers). Each pixel measures about 98 feet (30 meters) across. The color variation from yellow to red indicates increasingly more significant ground surface change. Preliminary validation was done by comparing the data to a crowdsourced map by Clemson Center for Geospatial Technologies and optical satellite imagery feom 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.