Coastal transgression and regression from 1980 to 2020 and shoreline forecasting for 2030 and 2040, using DSAS along the southern coastal tip of Peninsular India

Abstract

This study explains the multi-decadal shoreline changes along the coast of Kanyakumari from 1980 to 2020. The shorelines are extracted from the Landsat images to estimate the shoreline dynamics and future predictions using Digital Shoreline Analysis System (DSAS). By the estimation of End Point Rate (EPR) and Linear Regression Rate (LRR), it is quantified that the maximum erosion is 5.01 m/yr (EPR) and 6.13 m/yr (LRR) consistently with the maximum accretion of 3.77 m/yr (EPR) and 3.11 m/yr (LRR) along the entire coastal stretch of 77 km. The future shoreline predicted using the Kalman filter forecasted that Inayam, Periyakattuthurai and Kodimunai are highly prone to erosion with a shift of 170 m, 157 m and 145 m by 2030 and 194 m, 182 m and 165 m by 2040 towards the land. Also, the western coast is highly prone to erosion and it is predicted that certain villages are prone to loss of economy and livelihood. The outcome of this study may guide the coastal researchers to understand the evolution and decision-makers to evolve with alternative sustainable management plans in the future.