Social vulnerability to seismic-tsunami hazards in district Gwadar, Balochistan, Pakistan

Abstract

Social vulnerability illuminates differences in human capacity to prepare for, respond to, and recover from disasters. It varies over space and time and among social groups, largely due to variations in socioeconomic and demographic features. The Makran Subduction Zone is one of the known active seismic sources that can generate devastating shaking and tsunami disasters in District Gwadar, Pakistan, such as a large earthquake of moment magnitude 8.1 in 1945. This study presents the first social vulnerability index study for District Gwadar in relation to imminent earthquake-tsunami hazards and shows how SoVI concepts and indicators are adopted. SoVI follows a place-based framework that was originally adopted in developing social vulnerability index for the USA. To assess social vulnerability to earthquakes and tsunamis in Gwadar, we evaluate a social vulnerability index at village level. Using a principal component analysis, 16 village-level indicators are condensed to five factors that explain 64.2% of the variance in the data. Although different factors contribute to the social vulnerability in each village, the overall results confirm the social and economic disparities among villages and reflect differential vulnerability to natural hazards at local to regional scales. Finally, a map of social vulnerability index is compared with seismic-tsunami hazard maps to identify the communities living in risky zones. The approaches and results presented in this study will help emergency managers to identify community sub-groups that are more susceptible to disaster risks and to develop effective risk reduction strategies that are tailored to local conditions.