Evaluation of Flooded Buildings by Multi-Temporal Interferometric Coherence Using L-Band SAR Satellite Data

In recent years, there have been many cases of disasters in which flooding damage occurs over a wide area and at the same time due to extreme weather. In the case of such disasters, it is necessary to quickly grasp the full extent of the disaster and implement effective disaster response. In this study, multi-temporal interferometric coherence were created using ALOS-2/PALSAR-2 images, focusing on the inundation disasters caused by heavy rains in July 2018 and East Japan typhoon in 2019. Fundamental investigations were conducted for extracting flooded buildings. As a result, the possibility of classifying flooded buildings based on the multi-temporal interferometric coherence value was suggested from the aggregation of the average values within polygons of flooded and non-flooded buildings. In addition, it was considered that the extraction of flooded buildings using multi-temporal interferometric coherence requires consideration of the angle formed by the building direction based on the observation direction.