Nopphawan Tamkuan
Graduate School of Sciences and Technology for Innovation, Yamaguchi University,
2-16-1, Tokiwadai, Ube, Yamaguchi 755-8611, Japan
Masahiko Nagai
Graduate School of Sciences and Technology for Innovation, Yamaguchi University,
2-16-1, Tokiwadai, Ube, Yamaguchi 755-8611, Japan
The powerful earthquakes occurred in Kumamoto at the highest magnitude 7.3 hitting this prefecture on April 16, 2016 at 01.25 A.M. local time. This study proposed a method to utilize Sentinel-1A images to detect earthquake damaged areas. There were two images being used. One was before-earthquake images (on March 3, 2016 and March, 27 2016) and another was an after-earthquake image (on April 20, 2016). The method operated on interferometric coherence of sentinel-1A image. In order to estimate the damaged areas, the coherence change between the before-earthquake and during-earthquake pairs were processed. The damage map was produced by concerning into different classes comprised of the urban damaged areas, none and less damaged of the urban areas, and non-urban areas. This approach was compared with the ground-truth data, which provides high overall accuracy at 88% (kappa coefficient is 0.82). Consequently, Sentinel-1A could contribute the insightful geospatial information of the earthquake situation and support the disaster management.
Keywords
Damage Assessment, Sentinel-1A, Interferometric Coherence, Kumamoto Earthquake
Full Article available at https://dx.doi.org/10.20319/mijst.2019.51.2335