Ground motion by city › Pennsylvania
Satellite radar (NASA OPERA / Sentinel-1 InSAR) has measured vertical ground motion across Pennsylvania since 2016. The fastest-sinking Pennsylvania city we measure is Philadelphia at -17.9 mm/yr. 1 of the 1 Pennsylvania cities we cover are measurably sinking. Pick a city, or check any address.
SibFly reads NASA OPERA DISP-S1 (processed Copernicus Sentinel-1 radar) at a 30-meter grid and fits the multi-year trend at each cell. It is measured movement, not a model — a screening estimate from space, not an engineering survey. Developers and AI agents can pull the same data from the API.