Coastal vulnerability assessment of the Kasaragod Coast in Kerala, West Coast of India

Abstract Coastal zones are transition zones between the land and sea, characterised by unique coastal ecosystems and natural resources, making them the focal point of human activities. Vulnerability assessments have been carried out along several coastal zones across the world. These assessments help coastal scientists, engineers, and policymakers prepare plans and devise mitigation measures to safeguard the environment and coastal population against climate change and coastal hazard impacts. The present study evaluates the vulnerability of the Kasaragod coast in Kerala, the west coast of India, due to sea-level rise. Eleven variables, viz. relative sea-level change, mean significant wave height, tidal range, geomorphology, shoreline change rate, regional elevation, coastal slope, population, road/railway networks, tourist sites and land use/land cover are considered in the estimation of the Coastal Vulnerability Index (CVI). The resulting CVI values were categorized into low, moderate, high and very high vulnerability classes. Based on this classification, 41.33% of the Kasaragod sub-district and 13.26% of the Hosdurg sub-district fall under the ‘very high’ vulnerability category. A significant decrease in vulnerability was observed along the Kasaragod sub-district when socioeconomic variables were excluded from the CVI calculation. However, in the Hosdurg sub-district exclusion of the socioeconomic variables led to increased vulnerability along the coast. The vulnerability maps developed in this study provide a crucial tool for identifying highly vulnerable coastal stretches and guiding effective strategies to safeguard the Kasaragod coast and its communities.