An assessment of spatio-temporal pattern of urban earthquake vulnerability using GIS: a study on Dhaka City

Abstract

This study portrays spatial and temporal vulnerability associated with seismic events for an urban area. It describes the vulnerability of a potentially earthquake-prone area for different time periods. The study assesses changes in earthquake vulnerability in relation to the changing distribution of human population over space with time. It has resulted with vulnerability maps showing vulnerability at working and non-working hours for the study area. The study has performed with a complex methodology linking a set of spatial and non-spatial database onto Geographic Information System environment and then analyzed to derive the study outcome on equal area hexagonal grid. In the outcome, the vulnerability has been presented in five different vulnerability scales ranging from Low to Extremely High. Occupational and residing density of population over available space has been used in computing urban vulnerability. Finally, the study has come up with a combined vulnerability map showing Very High vulnerable areas to earthquake damage throughout a day. As a whole, the study can potentially contribute in effective disaster risk management to minimize losses and thereby improving urban sustainability through the knowledge of spatial and temporal vulnerability.