A GIS based coastal management system for climate change associated flood risk assessment on the east coast of England

Abstract

To assess the implications of sea level rise along the English east coast, the Arc-Info GIS package was used to determine coastal vulnerability to flooding. Results from oceanographic and climatic research were combined with data on sea defences, elevation values, and patterns of landuse. A risk assessment model was developed to estimate flood return periods according to different climate change scenarios for the years 2050 and 2100. Flood risks were modelled as a function of the height and condition of sea defences, land elevations, and subsidence rates. The ‘house equivalent’ concept was used to estimate damage costs of flood events in a future climate-changed environment. For the year 2100 the model predicts significant increases in flood damage costs. However, the results indicate the considerable uncertainty associated with sea level rise predictions. Our findings may potentially be of both academic and practical interest, but will be of little practical significance to coastal managers and planners if they cannot use them. To illustrate how this might be facilitated, their incorporation into an easy to use prototype Decision Support System (DSS) is outlined. The development of such systems is possibly the next major challenge for the application of GIS technologies to the coastal zone.