Use of ALOS/PALSAR imagery for monitoring areas damaged due to recent natural disasters

Synthetic aperture radar (SAR) has the remarkable ability to examine the Earth's surface, regardless of weather or sunlight conditions. A SAR-based remote sensing system can assess the damage to areas affected by large-scale disasters at an early stage. This can aid in recovery planning. On May 27, 2006 an earthquake struck Yogyakarta, Central Java, Indonesia, causing human suffering and severe building damage. PALSAR (Phased Array Type L-band Synthetic Aperture Radar) onboard the Japanese ALOS (Advanced Land Observing Satellite) imaged the affected areas on the morning following the earthquake. The European satellite, Envisat, also imaged a wider area of central Java two days after the event. This paper applies a damage detection technique based on three time-series images from the SAR dataset covering the Mid Java earthquake. From a macroscopic point of view, the estimated damage distribution closely matched damage assessment derived from high-resolution satellite images and field surveys.