A Modelling and Mitigation Strategy for the Impact of the Tsunami Disaster at Tamban Beach, Malang Regency, using a Geographic Information System

Abstract

Tsunami events are caused by a series of waves resulted from sudden changes in the water column, seismicactivities such as the eruption of underwater volcanoes,landslides on cliffs above or below the sea, andfalling asteroids. The Meteorology, Climatology, and eophysics Agency released a warning of a potentialearthquake in the southern part of Java Island, including the Malang Regency, with a magnitude of 8.7 onthe Richter’s scale. It means that a tsunami with amaximum inundation height of up to 22 meters coulddestroy Tamban Beach. The objectives of this study were1)to examine the spatial aspect of Tamban Beachand its relevance to the ecological aspect as well as thetime aspect related to the estimation,2) to formulatea strategy to save the community, and 3) to estimate the impact of the damage to cover and land use. Themethods used were a scoring technique and an overlay analysis using a Geographic Information System(GIS), with parameters including the distance to the coast and river from the sea, slope, elevation, land use,tsunami run-up prediction, and inundation model. The Partial Least Squares (PLS) method was used todetermine the relationship between the level of vulnerability of an area to the tsunami disaster with variousassessments and efforts to mitigate the disaster. The results showed that most of the coastal areas of TambanBeach had a moderate level of vulnerability, except for the residential areas that had a high level ofvulnerability. A tsunami mitigation strategy was significantly influenced by the area’s level of vulnerabilityto a disaster and the assessment of disaster management efforts.