The use of wave propagation and reduced complexity inundation models and metamodels for coastal flood risk assessment

To estimate coastal risk it is necessary to integrate the joint probability density function, including extremes, of the sea condition variables over a function that defines the consequences, typically economic damage. The use of M onte C arlo methods is common practice to undertake this integration; however, it can introduce a high computational burden for use in practical applications. Hence, a simplifying assumption of full dependence between the sea condition variables is often made. This paper describes a method that overcomes this simplifying assumption through the use of two techniques. A hybrid emulator of the simulating waves nearshore model is used to increase the computational efficiency associated with the wave transformations. In addition, a computationally efficient dynamic inundation model has been incorporated to further reduce the computational burden. To demonstrate the system, it has been applied to an urban coastal area located in northern S pain.