Coastal Vulnerability and Risk Parameters

The natural environment is unequivocally the life support for all human systems. Far for being a luxury available only to those who can afford it, successful environmental management will increasingly become the basis for the success or failure of the economics and social systems of entire countries. In the last two decades, concern has been expressed about possible effects of climate change in coastal areas. By the year 2100 the rate of global sea level rise may increase to over 10mm/year (pessimistic scenario), which would represent a sevenfold increase over present rates. The Coastal Vulnerability Index (CVI) is used to map the relative vulnerability of the western Pelleponese in Greece for a coastal length of about 50 Km. Along this coastline, ecological sensitive areas, Ramsar forests, drained coastal lakes, very important lagoons, riparian forests, magnificent beaches etc., form a coastal area which has to be carefully monitored and protected due to the accelerating sea level rise. Geomorphology, regional coastal slope, rate of relative sea level rise, shoreline erosion and accretion rates, mean tidal range and mean significant wave height are the physical contributors to the CVI calculation which highlights the regions where the effects of sea level rise might be the greatest. Each CVI is computed along a thousand of cross sections on 1/5000 digitized maps along the studied shoreline and all available and proposed formulas to calculate the CVI are used for comparison reasons. Using percentiles specially designed for Greece, the coastline is grouped to low, moderate, high and very high vulnerability from the effects of the rising sea level. In particular coastal areas where the CVI reaches very high numbers, digitized maps of 1/500 scale are used to cross-examine, validate and justify the high vulnerability of the coastal area. In an age of rising sea level, the CVI has become a necessary and important tool for locating the vulnerable areas with high degree of confidence.