DETECTION OF CATASTROPHIC TSUMANI DEVASTATION IN JAPAN BY USING OPTICAL AND SAR DATA

摘要

The catastrophe of Tsunami disaster has occurred over the wide area in the eastern part of Japan by the earthquake (M9.0) on 11 March, 2011. At that time, we performed the urgent analysis of optical and SAR satellite data for the detection of the catastrophic damaged area by Tsunami devastation. First of all, acquiring MODIS, the wide range devastation was detected regarding the inundated area occurred by Tsunami along the coastline of Miyagi and Fukushima prefectures. The maximum elevation height in the inundated area was identified to be 4 to 5 m and the maximum distance from coastline was 5.0 to 5.5 km according to the results derived from MODIS data. AVNIR-2 images after the earthquake were used for monitoring the inundated area in paddy fields of the damaged area. The inundated areas were detected by means of the difference of ratio of visible and infrared bands derived from AVNIR-2 of before and after the disaster. On the other hand, the change detection of the inundated area was also detected by means of the classified images derived from PALSAR L-band and COSMO -SkyMed X-band high spatial resolution SAR data, and PRISM and EROS-B high spatial resolution optical data taken on multi-temporal observations before and after the disaster. In addition, we have developed 3D viewing system for geospatial visualizing of the damaged area using these satellite image data with digital elevation model. The 3D viewing system has the performance of geographic measurement regarding distance, elevation height, area calculation and cross section drawing including landscape viewing and image layer construction using a mobile personal computer with interactive operation. As the result, it was verified that a quick response for the disaster identification at the initial stage could be performed using optical and SAR satellite data with 3D viewing system.