Inequality in Natural Hazard Exposure and Social Vulnerability in the Global South

Abstract

Insights about inequalities in natural hazard exposure and social vulnerability are important for improving disaster risk management and climate justice. However, in the natural hazard literature, the social vulnerability of and impacts on people are poorly reported or comprehensively understood. This is among one of the first studies, quantifying inequalities in natural hazard exposure depending on social vulnerability for several countries of the Global South, three hazard types, and two social vulnerability approximation datasets. We used the CLImate AD-Aptation (CLIMADA) platform to calculate whether socially vulnerable communities are more exposed to tropical cyclones, river floods, or wildfires than less socially vulnerable communities within a country. Therefore, we established the Inequality Coefficient, analogous to the well-known Gini Coefficient. We found that for the majority of the 93 countries from the Global South, socially vulnerable communities are more exposed to wildfire and less exposed to river floods compared with less socially vulnerable communities. For tropical cyclones, we observed no tendency across all countries. In general, and for all three hazard types, the extent of inequalities varies greatly across countries. In the case studies of Vietnam and Cambodia, we observed that mainly the socially less vulnerable communities live near rivers in cities and are more exposed to river floods. In contrast, wildfires primarily affect socially vulnerable communities living in rural areas. Another important finding is that the magnitude of inequalities strongly depends on the data used to approximate social vulnerability. This emphasizes the need to improve the quality, resolution, coverage, and validation of data to approximate social vulnerability. Despite the high uncertainty of the magnitude of inequalities, we could quantify and compare the inequalities of several countries. Thus, we highlighted countries and areas within countries where inequality in natural hazard exposure depending on social vulnerability is high. The method used could be applied to examine inequalities on a global level, inequalities between countries, or inequalities on a local level within cities. This is an important basis for monitoring sustainable development goals and for disaster risk reduction. In addition, the Inequality Coefficient can be used to compare how inequalities will change in the future with the increasing frequency and magnitude of extreme events due to climate change. This contributes to a fact-based climate justice discussion and enables statements about who carries the natural hazard risk.