Variation of Impact along the East Coast of Eastern Samar Due to Typhoon Haiyan in the Philippines

抄録

The east coast of eastern Samar in the Philippines faces to the Pacific Ocean and suffered significant damage due to storm waves caused by Typhoon Haiyan. The coast has various characteristic features such as fringing coral reef, varying beach slopes, pocket beaches and well-developed mangrove forest especially inside Matarinao bay. This paper aims to investigate how this characteristic coast was affected by the catastrophic typhoon event mainly through observations of satellite images. Various types of optical satellite images were utilized to capture the changes before and after the typhoon event. Comparisons of satellite observations and numerically computed wave height distributions along the coast clearly showed that the coast inside the bay was strongly protected by sand spit with fringing reefs and thus mangrove strip inside the bay was less damaged. It was also found that estimated penetration distance of wave runup on the beach showed certain correlation with the local width of fringing coral reefs.