Map of the Coastal Vulnerability Index (C.V.I.) for the U. S. Gulf Coast. The C.V.I. shows the relative vulnerability of the coast to the changes due to the future rise in sea-level. Areas along the coast are assigned a ranking from low to very high risk, based on the analysis of physical variables that contribute to coastal change. (Source: http://pubs.usgs.gov/of/2000/of00-179/).