GIS-Based Approach to the Assessment of Coastal Vulnerability to Sea Level Rise: Case Study on the Eastern Mediterranean

Abstract

Accelerated Sea Level Rise (SLR) is usually regarded as the most certain consequence of global warming. SLR has serious physical impacts on coastal areas, mainly characterized by inundation risk and displacement of lowlands and wetlands. The increasing coastal inundation vulnerability may lead to substantial socio-economic losses such as the loss of coastal structures, damage to buildings and settlements, dislocation of the population, and the loss of the agricultural production. This study addresses the risk assessment of physical and economic impacts under different SLR scenarios and the analysis of the effects due to SLR (i.e. extended coastal inundation, coastal erosion on populations, land use, etc.). A degree of vulnerability analysis based on different criteria has been carried out to better locate which sectors are more vulnerable to the possible sea level rise (SLR). These criteria include geomorphology, slope (land topography), and sea-level rise (SLR). The aim of the present study is to assess the Coastal Vulnerability Index (CVI) incorporating main factors acting on the coastal area (erosion/accretion patterns, topography, subsidence and relative sea level rise). The output is to determine the coastal degree of vulnerability due to SLR. Another aim is to provide measurements of inundated area in relation to different sea-level changes. Possible consequences of sea-level rise and corresponding mitigations are also discussed. Topographic maps 1:50000 were used for the extraction of contour lines. Ground control points (GCP) were used for image orthorectification; contours are then employed to develop a high accuracy DTM which is for the risk assessment of inundated areas; Landsat and Ikonos Images at different time frames (from 1972 to 2005) are used to delineate the coastline development; land cover land use map, geomorphologic map, population density map, are all used for coastal vulnerability assessment. Results reveal that the Syrian coastal area is vulnerable to accelerated sea-level rise but not at the same level in all regions. KeywordsSea Level Rise; Coastal Vulnerability; DEM; GIS; Climate Change