Spatial heterogeneity of the integrated risks of urban heat stress and flooding strike

Clarifying the spatial heterogeneity of the multiple climate-related risks has increasingly become a prerequisite for urban risk management and sustainability. As the datasets become more detailed in social attribute's representation at the fine scale within-city level, in contrast to those at a coarse region level, there is a continuous need to examine the spatial heterogeneity of integrated risk assessment. In this study, we applied the hazard-exposure-vulnerability framework to investigate the spatial variations of the integrations of urban heat stress and flooding strikes at the street block scale within Shenzhen, China. The findings showed approximately 16.85 % of the built-up areas experienced a strong dual pressure of heat and flooding, mostly concentrated in the street blocks constructed before 1990. Another 19.84 % of built-up areas exhibited a high level of heat risk, concentrated in the northern urban areas that developed in the recent period. While 26.28 % demonstrated a high level of flooding risk, located in the old urbanized areas. Such spatial variations of integrated risks resulted from the spatial mismatched hotspots among hazard, exposure, and vulnerability. The spatial heterogeneity of the integrated risk assessment suggests differentiated strategies to reduce the maladaptation of urban heat stress and flooding strike. The findings present opportunities to prioritize the street blocks and develop the most sustainable solutions.