Understanding and addressing social vulnerability is central to building sustainable and resilient cities, particularly in rapidly urbanizing coastal regions where inequality, infrastructure deficits, and environmental risks converge. This study maps the spatial distribution of social vulnerability in Greater Chennai, India, through a geospatial framework that enhances the spatial relevance of census indicators. A land use/land cover (LULC) map derived from Sentinel-2A imagery using Random Forest classification was used to isolate residential and mixed-residential areas, enabling disaggregation of ward-level census indicators only to inhabited extents. This refinement improves spatial accuracy and captures intra-ward variations that are often obscured in conventional assessments. Vulnerability was assessed using housing quality, access to basic facilities, and key socio-economic variables, with weights derived through the Analytic Hierarchy Process (AHP). Results indicate that 62.5% of the city’s wards fall within high or very high vulnerability, concentrated in North and Central Chennai, coastal belts, and informal settlements. Certain wards, typically considered less exposed, were identified as having comparatively higher vulnerability when census indicators were redistributed to inhabited areas. These zones combine high population density, ageing infrastructure, and limited access to sanitation and drainage, intensifying disaster sensitivity. The framework, being low-cost and reproducible, offers a scalable tool for supporting strategic and comparative urban planning, disaster preparedness, and long-term sustainability in hazard-prone megacities.
Manoharan et al. (Wed,) studied this question.