Assessment of the Sensitivity of Salamina (Saronic Gulf) and Elafonissos (Lakonic Gulf) islands to Sea-level Rise

Karymbalis, E., Chalkias, C., Ferentinou, M., Chalkias, G., Magklara, M. 2014. Assessment of the Sensitivity of Salamina (Saronic Gulf) and Elafonissos (Lakonic Gulf) islands to Sea-level Rise. In: Green, A.N. and Cooper, J.A.G. (eds.), Proceedings 13th International Coastal Symposium (Durban, South Africa), Journal of Coastal Research, Special Issue No. 70, pp. 378–384, ISSN 0749-0208. This paper deals with the classification of the coasts of two Greek islands (Salamina and Elafonissos), according to the sensitivity to long-term sea-level rise by applying the Coastal Sensitivity Index (CSI). Salamina lies in the Saronic Gulf about 2 km off-coast from Piraeus (the port of Athens). The island has an area of 93.5 km2 while the total length of the coastline is 131.3 km. Elafonissos has an area of 19 km2 (coastline length: 30.4 km) and lies west of cape Maleas in the Lakonic Gulf (South-east Peloponnese). CSI calculation involves the physical variables of geomorphology, coastal slope, relative sea-level rise rate, shoreline change rate, mean tidal range and mean wave height, in a quantifiable manner. Every section of the coastline is assigned a risk ranking based on each variable, and the CSI is calculated as the square root of the product of the ranked variables divided by the total number of variables. CSI maps which were produced for the studied islands showed that Elafonissos is more susceptible to a future sea-level rise since an extensive length of its coast (16.7 km, corresponding to 54.5% of the entire coastline) is characterized as highly and very highly sensitive primarily due to the low topography and the presence of extensive sandy beaches. On the other hand only 2 km of Salaminas' shoreline, corresponding to 1.5% of the entire coast of the island, is of high sensitivity. Areas of high and very high CSI values host socio-economically important land uses (urban areas and recreational activities).