Synthetic Aperture Radar Interferometry for Disaster Monitoring of Harbor Facilities

In this paper, we present experimental results of the disaster monitoring of harbor facilities using spaceborne synthetic aperture radar interferometry (InSAR). The Advanced Land Observing Satellite-2 (ALOS-2 or DAICHI-2), operated by the Japan Aerospace Exploration Agency (JAXA), carries the Phased Array type L-band Synthetic Aperture Radar-2 (PALSAR-2). PALSAR-2 can observe disaster areas day and night, in any weather, at a resolution of approximately 3 m. ALOS-2 PALSAR-2 has been used to measure large-scale ground deformation e.g., after earthquakes and volcanic eruptions. However, its robustness for smaller targets, such as harbor facilities, has not yet been substantiated. Here, we measured the uplift of a breakwater model made of concrete armor units, and confirmed the sensor accuracy to be better than 2 cm standard deviation. We also analyzed the damage to the Nagata and Suma ports in Kobe city, Hyogo prefecture, Japan hit by the 11th Typhoon in 2014, and detected the damaged area using interferometric coherence analysis.