Unfolding the Spatial Inequality of Neighborhood-Level Social Vulnerability to Flood Hazards During Urbanization in China: Nanjing as a Case Study

Progressive global change and rapid urbanization have intensified the vulnerability of cities, especially megacities, to extreme climatic events and disasters. Urban areas, whether well planned or poorly developed, face new and complex challenges in terms of emergency management. To address these challenges, we present an integrated methodology for quantifying social vulnerability at a fine spatial resolution by combining and utilizing open data from various web sources, which enables precise measurement and makes such analyses more accessible for regions facing data availability challenges. Neighborhood social vulnerability is divided into two spatially distinct components: one focuses on internal neighborhood attributes, which shape the sensitivity of neighborhoods to natural hazards, and the other emphasizes the spatial accessibility of neighborhoods to urban public services, representing neighborhood adaptability. By examining these two components, we reveal significant spatial inequalities in both sensitivity and adaptability, highlighting the presence of “uneven development” between urban centers and peri-urban areas. These findings help with the integration of social vulnerability reduction into urban planning and governance, thereby promoting resilient development and the ability to effectively respond to multifaceted disaster risks.