Spatial and temporal changes in social vulnerability to natural hazards: a case study for China counties

Enhancing disaster risk governance is crucial for improving the ability to cope with and adapt to the impacts of climate change. China experiences a diverse range of natural disasters distributed widely across the country. The evolving demographic, socio-economic, and geographic landscape requires heightened attention as it significantly shapes the extent and dynamics of regional vulnerability to natural hazards. This study aims to evaluate the spatial and temporal changes of social vulnerability in China based on data at the county level in the years of 2000, 2010 and 2020. The Social Vulnerability Index (SVI) was constructed by adopting nine demographic and socio-economic variables drawn from the variables in the US CDC SVI framework using Principal Component Analysis. Both economic development and demographic factors played important roles in determining the patterns of spatial distribution of SVI over the period. Result of spatial data analysis reveals distinctive and stable spatial heterogeneity of social vulnerability across counties. Furthermore, we applied the SVI with real-world impact data to validate the effectiveness and relevance of the constructed index. Using drought risk as an illustrative example, the research also assessed the applicability of the SVI in evaluating drought risks in China, considering hazard, exposure, and vulnerability. Public and private decision-makers can use the constructed SVI to identify hot spots and population subgroups that are most vulnerable to natural hazards to inform and facilitate adequate risk prevention and management at the national and local levels.