How just is the low-carbon transition in coastal areas? Development of a composite vulnerability index for coastal low-carbon transition

The transition toward a carbon-neutral society requires social and economic sacrifices in certain regions, and the vulnerability of specific areas to low-carbon transitions may be particularly pronounced in coastal regions. This study focuses on the development and application of a composite vulnerability index that can assess climate justice in coastal areas from a low-carbon transition perspective. Facilitated by the developed indices, this study, focuses on investigating regional disparities stemming from the transition and exploring various policy options for alleviating the resulting burdens or damages associated with these inequalities. The initial step in developing indicators involved creating a scoping diagram to define the scope of vulnerability and to identify specific indicators for coastal low-carbon transition vulnerability. Subsequently, based on the parameters, dimensions, and measurement factors presented in the diagram, composite vulnerability indices were formulated. In the process of calculating the vulnerability index, weights were assigned to the indicators at both quantitative and qualitative levels, reflecting vulnerability factors and dimensions. Finally, the Coastal LowCarbon Transition Vulnerability Index (CLCTVI) was established for three sectors: marine fisheries, carbon sink, and energy development. The CLCTVI was then applied to coastal regions in South Korea, and its regional and sectoral patterns were analyzed using basic statistics, scatter plots, parallel coordinate plots, and the geodetector method. The findings of this study highlight the following key points: the degree of vulnerability in coastal areas to lowcarbon transitions varies across regions; the main factors contributing to high or low vulnerability in low-carbon transitions differ for each sector; only a few regions are simultaneously vulnerable across all sectors. In particular, various interactive effects among factors were identified in each sector, underscoring the need for considering the interactions among factors alongside dominant factors for sector-specific vulnerabilities in policy support for regions exhibiting low-carbon transition vulnerabilities. This study showcases how CLCTVI can effectively capture interregional disparities resulting from low-carbon transitions in coastal areas, thus providing insight to decision-makers regarding previously unaddressed regional disparities associated with low-carbon transitions.