In today's PI meeting, the UMass group presented example images of regions affected by the recent landfall of Hurricane Ida near New Orleans. A change analysis of the Capella SAR images of a region around an oil refinery (see September 8 update) enabled the generation of a simple map of flooded areas (not shown here). Furthermore, a Capella SAR image of Grand Isle, LA, acquired on September 10, was compared to a Google Earth image from the time before the hurricane and a composite aerial photograph from NOAA survey flights between August 30 and September 1, after the hurricane. The buildings and other structures visible in the aerial photographs are resolved by the SAR as well. Furthermore, the SAR image reveals that the main road along the island, which was still covered by mud at the time of the NOAA flights, had been cleared by September 10.
While these examples show what kind of information can be derived from simple SAR intensity images, the temporal order of the aerial survey and the later SAR image acquisition is not representative of what we intend to achieve in this project. The capability of spaceborne SAR to acquire images independent of weather conditions and sunshine should usually allow us to acquire SAR images during or very soon after a hurricane's landfall, before optical images can be taken from aircraft, drones, or satellites.