Assessment of the Future Changes in the Socio-Economic Vulnerability of China's Coastal Areas

China's coastal areas are under serious threat of continued sea-level rise, and sustainable coastal development is closely linked to changes in socio-economic vulnerability. To this end, based on the Intergovernmental Panel on Climate Change framework of shared socio-economic pathways (SSPs), this study constructed a system of indicators to assess the socio-economic vulnerability of China's coastal areas in 2030, 2050, and 2100 under low, medium, and high greenhouse gas emission scenarios (SSP1-2.6, SSP2-4.5, and SSP5-8.5, respectively). The results showed the following: (1) the vulnerability of China's coastal provinces, cities, and counties shows an upward trend (ranked SSP5-8.5 > SSP2-4.5 > SSP1-2.6), which is mainly attributed to a continued increase in the exposure of socio-economic systems to sea-level rise and differences in the age structure of the population within the study regions; and (2) areas with higher vulnerability are concentrated in economically developed coastal areas, such as the Bohai Bay Rim and the Yangtze River Delta, Jiangsu, and Pearl River Delta regions, owing to their high proportions of low-lying land, long coastlines, and dense residential areas associated with economic development. Based on these results, climate-resilient solutions are needed to improve socio-economic adaptations for ongoing climate change in China's coastal areas.