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Subsidence in the Samoan Islands increased dramatically after the M8. 1 2009 Samoa-Tonga earthquake. In addition to dramatic coastline changes, continued subsidence has also increased the frequency of coastal flooding and risk of saltwater intrusion, coastal erosion, and infrastructure damage. Developing effective resilience measures requires quantifying the extent of these changes and forecasting the rate of ongoing subsidence on the Islands of Tutuila, American Samoa and Upolu, Samoa. Here, we present results using a multi-sensor approach to tracking coastal changes and subsidence in the Samoan Islands. With a combination of multi-frequency interferometric synthetic aperture radar (InSAR) at C-and L-bands, satellite altimetry, tide gauge, and GPS/GNSS measurements, we identify areas across the islands where changing coastlines are most exacerbated by subsidence. We also highlight how …