Temporal evolution of shoreline changes from 1972 to 2020 along the coast between Pondicherry and Point Calimere, East Coast of Tamil Nadu, India

The aim of this study was to estimate the changes in shoreline evolution that have occurred between 1972 and 2020. The intervals of analysis were 1980, 1991, 2000, 2005, and 2020. The findings suggest that there were hotspots of erosion along the coasts of Gunduppalavadi, Thandavarayan, Kattur, and Rajamadam, while there was accretion along Cuddalore, Kothattai, Pudupattinam, and the eastern parts of Thiruppoondi. The study highlights that most of the regions from Portonova to Point Calimere are at risk from a sea level rise of 2 m, and almost all the coastal stretches are at risk from a sea level rise of 2 to 5 m. The results of the study show that the shoreline changes from 1972 to 2020 were estimated and represented as 29.84% stable, 66.74% as accretion, and 3.45% as erosion during 1980. For 1991, the nature of the coast shared 69.66% accretion and 30.34% stability. In 2000, the coast represented 35.73% stability, 62.76% accretion, and 1.51% erosion. The findings suggest that the behavioral change on the coast during 2005 was 54.80% stable, 19.31% accretion, and 25.90% erosion. In 2020, the percentage of stable, accretion, and erosion represented 56.76%, 28.88%, and 14.37%, respectively. The study provides important insights into the changes in shoreline evolution that have occurred over time and the potential risks associated with sea level rise.