In this Sentinel-1 radar image, red dots represent points where the ground was moving away from the satellite at a rate of more than 70 millimeters per year. Green dots show stable ground in the surrounding area. (Credit: Contains modified Copernicus Sentinel data (2015“17), processed by Norut)
On May 20, 2017, more than a million tons of dirt and rock buried part of California's Highway 1 along the Pacific coastline in the state's Big Sur region. In addition to cutting off the route, the landslide added some 12 acres of land to the shoreline.
The European Space Agency (ESA) Sentinel-1's radar shows that the ground that slid down the mountain was moving in the two years before the landslide. The radar data were processed using Small Baseline Subset interferometry (SBAS), a technique that can detect and monitor movements over wide areas with high sensitivity.
