Assessment of the integrated coastal vulnerability index of Ghana toward future coastal infrastructure investment plans

Abstract

Coastal vulnerability assessments are increasingly more important to investigate the exposure of coastal areas to coastal hazards. In recent decades, climate-induced sea-level rise (SLR) and human anthropogenic impacts are exacerbating the frequency and intensity of coastal hazards like storms, coastal erosion and flooding worldwide making coastal vulnerability assessments and coastal adaptation planning a priority. In Ghana, the assessment of the coastal vulnerability index (CVI) during the past decade has been infrequent, site-specific, and not complementary to provide the complete state of national coastal vulnerability during the past decade. This creates uncertainty, with limited information for coastal adaptation planning. To close this gap, we integrated three social variables with six fundamental physical variables to develop an integrated coastal vulnerability index (ICVI) for the coast of Ghana using the analytical hierarchical process (AHP). The ICVI results indicate that 6 coastal districts (18.18%) have very high vulnerability, 10 (30.30%) have high vulnerability, 8(24.24%) have moderate vulnerability, 6(18.18%) have low vulnerability, and 3 (9.09%) have very low coastal vulnerability. Overall, 72% of the coast exhibit moderate to very high coastal vulnerability. The results are significant to update the state of coastal vulnerability and help coastal planners to revise the short, medium, and long-term coastal adaptation policies along the coast of Ghana.