Prediction of tsunami inundation zone using gis spatial modelling for coastal region (Gaza strip - case study)

Gaza Strip is very crowded compared with its size with a majority of the population located near the shore which make them very vulnerable to tsunami risk. GIS-based multi-criteria decision analysis and spatial modelling are utilized to combine different types of data, both spatial and non-spatial data to be processed into tsunami exposure area information and to identify the most vulnerable locations to tsunami disaster. Modelling of the inundation was carried out with mathematical calculations developed by Berryman (2006). By modeling the tsunami with a worst-case scenario of wave height of 20 meters. Multiple geographical factors such as topographic height and slope, topographic connection to tsunami direction, coastline proximity, and coastal form are used in the study. Expert knowledge is also included using the Analytic Hierarchy Process (AHP) to develop a weighting system for the geographical variables. Tsunami risk assessment is carried out by developing a Composite Index in the form of a Total Vulnerability Index (TVI) which is a combination of the Physical Vulnerability Index (PVI), Social Vulnerability Index (SVI) and Economic Vulnerability Index (EVI). The results are used to determine new assembly points based on the Sentinel 2A imagery and to determine the most effective evacuation route by using network analyst. Tsunami arrival and evacuation time was calculated and finally, tsunami waves generated by wind was investigated for 3 scenarios using Delft 3D.