Vulnerability of south east coastal villages of India on sea level rise

Abstract

Sea level rise is one of the evident ill effects of climate change. As per the fifth assessment report of IPCC the rate of sea level rise has increased in recent years as compared to the previous years. The rapid rise in sea level can have devastating effects on the densely populated coastal areas, mainly by way of inundation of low lying habitats. Inundation of highly populated coastal areas exposes the location to coastal hazards and increases the risk to both life and belongings of people at the location. Therefore, identification of vulnerable areas becomes necessary for coastal zone management. The present study maps the Low Elevation Coastal Zones (LECZ) of Andhra Pradesh and Tamil Nadu and estimates the vulnerability of each coastal village based on population and elevation. The coastal villages with high percentage of low elevation zones and high population density are the most vulnerable areas and a vulnerability index is formulated as a product of these two variables. Landforms along Andhra Pradesh and Tamil Nadu coast include low lying alluvial plains, bays, tidal mudflats, creeks, ridges, bars, spits, mangrove swamps, marshes, and lagoons, which are subject to sea level rise. Maps for the study were produced using ArcGIS 10. The boundary maps were collected from the DataMeet project and the elevation data from ETOPO1. Population density data were collected from the NASA Socioeconomic Data and Applications Center (SEDAC). Increase in water level leads to higher rates of erosion that result in beach loss, enhancing the vulnerability of the coastal area to hazards. The analysis shows that Losari Gutlapadu and Sadayankuppam are the most vulnerable villages in Andhra Pradesh and Tamil Nadu respectively. Mapping of the vulnerable areas act as advisories and can help the state governments to develop mitigation strategies.