Assessing global-scale coastal vulnerability and identifying the dominant contributors

Coastal environments are among the most valuable and dynamic regions on Earth, supporting diverse ecosystems, high biological productivity, and socioeconomic activities. However, these coastal regions are increasingly exposed to hazards such as coastal flooding and erosion. The risks caused by these hazards depend not only on the level of hazards but also on the vulnerability of the exposed coastal environments. Therefore, in prioritizing the adaptation efforts, it is important to have a robust understanding of the coastal vulnerability to flooding and erosion. The Coastal Vulnerability Index (CVI) is the most widely used approach for assessing coastal vulnerability, integrating multiple geophysical indicators into a single relative measure of vulnerability. While CVI assessments have been extensively applied at local and regional scales, methodological differences and limited data availability have constrained the development of consistent global-scale analysis, which is important for informing the macro-scale decisions. By employing currently available global datasets together with the widely used Coastal Vulnerability Index (CVI) approach, this study assesses present-day coastal vulnerability at the global scale and analyses the vulnerabilities at country, IPCC AR6 region level and for different coastal typologies. Further, contribution of each indicator to the CVI is calculated to understand the dominant indicators in CVI.