Assess the human and environmental vulnerability for coastal hazard by using a multi-criteria decision analysis

This study provides an integrated approach using geographical information system (GIS) based on a multi-criteria approach (MCDA) to assess coastal vulnerability, resulting from human activity, population density, erosion, and climate change-induced sea level rise. A coastal vulnerability index (CVI) for erosion and floods was calculated and mapped (∼24 km in length; ∼400 m in width, and 11.47 km² in surface) for the lagoon barrier of Nador located on the Mediterranean coast of Morocco. Results suggest that 54% (∼13 km) of the shoreline is moderately vulnerable, while 42% (∼10 km) is highly vulnerable and only 4% (1 km) present a low vulnerability. The vulnerability map of the socio-economic activities indicates that most wetlands and forest areas 83% (∼31 ha) and 50% (∼440 ha) respectively, present low vulnerability. 52% percent of artificial areas (∼23 ha), 73% of agricultural land (∼128 ha), and 41% of natural areas (∼363 ha) present moderate vulnerability. However, the level of vulnerability of the remaining artificial and agricultural areas classifies from high to very high. The north-western sector was classified as the most vulnerable area, characterized by an erosion (−0.6 m/yr to−1.20 m/yr) for 70% of this area, while the south-eastern part shows a low to moderate vulnerability marked by an erosion (−0.1 m/yr to −1m/yr) for 40% of this area. Coastal vulnerability maps have potential as decision tools to prepare and respond to sea level rise, and identify exposed coastal zones, as such contributing to national climate action and disaster risk reduction sustainable development goals (goals 13 and 11, respectively).