Coastal area impact and vulnerability assessment: a morphodynamic modeller's point of view

Long-term (> 10 years) prediction of morphological behaviour in the coastal zone in response to both direct and indirect human interference and projected climatic change is an increasingly important issue in coastal management. As our recognition of the possible impacts increases, so does the need for more comprehensive model-based approaches to better assess long term impacts and plan precautionary interventions. Such models need to be integrated embracing both the morphological subsystem and the ecological subsystem, and their interactions in the coastal zone.By explicitly considering the "need for integration between different disciplines", this paper briefly describes possible approaches to modelling long-term dynamics of coastal morphology, particularly the modelling of coastal evolution in the typical situation: limited data and limited process knowledge, and further complicated by the variability of the coastal space cover and coastal space use. It is argued that progress in long-term modelling of coastal morphology will be further stimulated by adopting a conceptual framework which can embrace all the data, information, knowledge and experience concerning the coastal system of interest, whatever form they have. The objective can be accomplished by using a top-down modelling conceptual approach which helps to formalise knowledge and experience concerning the coastal area and integrate all the available data, information and models, including qualitative understanding. Qualitative modelling, which defines tendencies of evolution, offers an important tool for this goal. The overall approach lends itself to being structured into a model-based Decision Support System (DSS), coupled with Geographic Information System (GIS) technology which represent the state-of-the-art of decision support tools in the environmental fiel