Vulnerability Analysis of Sea Level Rise (SLR) on a Micro-tidal Coast: A Case Study of Nagapattinam Coast

Abstract

The IPCC sixth assessment report shows that the world will probably reach or exceed 1.5 degrees C (2.7 degrees F) of warming within just the next two decades and the oceans will rise between 10 and 30 inches (26–77 cm) by 2100 (Globally). The report highlights that the sea levels in South Asia could rise by 0.4 m in the low emissions scenario, about 0.5 m in the current pledges scenario, and 0.7 m in the high emissions scenario. Sea levels rise (SLR) has been rapidly increasing, with devastating effects on coastal habitats farther inland, it can cause destructive erosion, wetland flooding, aquifer and agricultural soil contamination with salt, and lost habitat for fish, birds, and plants. Studies by Indian scientists reveal that the trends of sea level rise are estimated to be 1.3 mm/year along the Indian coasts during the past 40–50 years (Unnikrishnan et al., Curr Sci 90(3), 2006). Also, impacts of storm surges, tsunamis, coastal floods, and coastal erosion in the low-lying coastal area cause gradual loss of coastal land. In the present study, the impact of sea level rise on the sandy coast of the Nagapattinam sector is assessed to understand the devastation incurred in both physical and socioeconomic aspects. In the analysis, it is further noted that the exposed vulnerable sectors to sea level rise are increasing with changing climate. The quantitative SLR impact assessment method suggested in the study forms the basic framework for coastal planners in disaster mitigation and building a climate-resilient community.