Determination of the vulnerability and the coastal risk by the application of GIS tools and multicriteria methods

Abstract

A scientific consensus exists regarding the significant impact on the global climate, including changes in rainfall patterns and sea level rise, among others. Although the magnitudes of these changes still are not clear, the analyses of the vulnerability and risk along the littorals represent the first step to design an adaptation plan of the climate change. With this in mind, the selected study area was the District of Cartagena de Indias, Colombian Caribbean Coast. It is located in the coordinates 10°45’N-75°15’W and 10°10’N-75°45’W and its littoral has an approximate length of 370 km. A detailed evaluation of the vulnerability and the risk by erosion along  his littoral was carried out, considering physical, social, conservational and heritage aspects. The analysis was made by semiquantitative approximation method, applying relative indexes: geomorphologic unit, width, the slope and  ype of beach, degree of exhibition of the coasts to the waves, between others. Initially, the available information was of shoreline retreat, land uses, conservation and heritage. The results showed erosion rates bigger than 3 m year-1 in critical sectors (Playetas and Tierrabomba), between 1994 and 2011, and the land  se and local and regional economy were affected. 41% of coastline was classified with low and very low risk, 32.15% with moderate risk, whereas 13.69% and 13.27% had values of high and very high risk respectively.  nder climate change conditions, sea level rise and sediment imbalance, the coastal erosion along of the District of Cartagena de Indias will be intensified by the shoreline retreat in a short, medium and long term. The adaptation must be a priority strategy, to being considered  ith alternatives of relocation, sustainable protection and littoral zoning to human settlement, land uses and future applications.