Remote sensing in support of tsunami mitigation planning in the Mediterranean

Remote sensing has emerged as a powerful tool for mitigation planning and post-crisis assessment in various natural hazards. The development of advanced remote sensing technologies has improved mapping capabilities and expanded areas of application. The most significant improvement is the commercialization of very high spatial resolution satellite data. Here, remote sensing data and methods were used to support the development of tsunami inundation maps for the City of Rhodes, Greece, as well as to help ground truthing modeling results. Information about the topography was derived using both satellite and aerial images. ASTER (Advanced Spaceborn Thermal Emission and Reflection Radiometer) stereo images were used to provide a Digital Elevation Model (DEM) for the whole island, whereas aerial imagery was used to derive a high resolution DEM for the Northern part where the city of Rhodes is located. These DEMs were used to orthorectify multispectral ASTER and Ikonos images, respectively. Land cover/use was extracted for the coastal area of Rhodes using both ASTER and Ikonos images. The latter was also used to extract the shoreline and information about the main buildings. The DEMs and the shoreline were used in the numerical computations of inundation, whereas the orthorectified products were used to validate the resulting inundation estimates on the ground. Finally, contour lines which extracted from the high resolution DEM along the inundation lines revealed the topographic controls on tsunami inundation.