Coastal vulnerability assessment along the coast of Kerala, India, based on physical, geological, and socio-economic parameters

Abstract

The increase in population and rapid economic development activities increase vulnerability along the coastal areas. Coastal zones are among the planet’s most dynamic regions and are susceptible to natural and anthropogenic hazards. To comprehend how risks and hazards are distributed spatially along the coast, coastal vulnerability assessment is crucial. This study aims at identifying the vulnerable zones along the coast of Kerala, India. For this, the coastal vulnerability index (CVI) is calculated by considering the physical, geological, and socio-economic parameters. The physical-geological parameters considered are nearshore bed slope, shoreline change rate, coastal elevation, tidal range, and continental shelf width. The socio-economic parameters include population density, road network, and land use/land cover. Analytical hierarchy process (AHP) is used for obtaining weights for physical-geological and socio-economic parameters. Coastal vulnerability results show that 82.40 km of the coastal stretch has a very high CVI value along the coast of Kerala, accounting for 13.87% of the total coastline. The most vulnerable stretches are along the coast of Kozhikode, Malappuram, Thrissur, Ernakulam, Alappuzha, and Trivandrum districts while Kasargod and Kannur districts have no coastal stretches with very high CVI. High population density, low nearshore bed slope, low coastal elevation, high erosion rates, built-up areas, and roads near to the coastline are some of the factors contributing to very high CVI in coastal districts of Kerala.