Vulnerability to sea level rise of an estuarine island in southern Brazil

This article presents a sea level rise vulnerability map built for Marinheiros Island, South Brazil, through specific routines for support decision in a Geographical Information System. A previous environmental diagnosis allowed the recognition of 5 vulnerability factors including physical, biotic and socio-economic variables. Each one was standardized to a continuous scale of values using the fuzzy approach, and later, analyzed together by multi-criterion evaluation module of the software to produce the final map. The most vulnerable areas are located at the northeast margins of the island as a result of the coincidence of several of the considered factors. In the remaining areas the vulnerability values decrease progressively from the margins to the center. Although the final result tends to be subjective because it is the decision maker what determines the criteria, the factors, the individual weighting and the decision rules, exercises of projection as performed in this work are very useful to explore certain alternatives and to insert sea level variable in the urban planning