GEOSPATIAL MODEL OF PHYSICAL AND SOCIAL VULNERABILITY FOR TSUNAMI RISK ANALYSIS

Abstract

Tsunami risk assessment is required to support preparedness activities and effective disaster
reduction. In this study, the analysis of physical and social vulnerability for tsunami risk assessment was
applied for tsunami mitigation activities in coastal areas. The analysis was applied in the southern coastal
area of East Java, Indonesia. The application of Geographical Information System (GIS) was used to capture,
store, manipulate, analyze, manage, and visualize geographic data used for tsunami risk analysis. GIS makes
possible in integrating a complex layer of the geographic phenomenon and the parameter of tsunami
vulnerability. In this case, the spatial overlay of physical and social vulnerability was done using spatial
multi-criteria approach. Physical vulnerability parameters analyzed in this study were elevation, slope, land
use, and distance from the coast. While the social vulnerability parameters include the number of population,
age distribution, number of women, and people with disabilities. The results described the visualization of
possible damage and loss areas that may result from a tsunami attack. The analysis illustrated that the most
vulnerable areas of the tsunami were areas with low elevation, very sloping slopes, areas that close enough to
the coastline and the land use type of residential class. The areas with high vulnerability class also illustrated
by social vulnerability parameters especially population density. The estimates of affected areas due to
tsunamis can help the decision-makers in mitigating the possible consequences of tsunamis, managing the
emergency response related to the tsunami disaster, and developing plans for recovery and reconstruction
after the tsunami event.