Discussion. 1a: Flooding and Overtopping

1.1 OST Foresight Report - a futures analysis of coastal flooding and erosion

I Townend & J Simm

1.2 Experience of the Indian Ocean Tsunami on the Sri Lankan coastS Hettiarachchi

1.3 New results on scale effects for wave overtopping at coastal structuresJ Geeraerts

Discussion to paper 1.1

Phil Barber (SMP) -The authors are congratulated on a substantial piece ofwork. What did the modelling team do to quantify uncertainty, and how were the cumulative effects of individual uncertainties assessed? Was there sufficient overlap between the four scenarios modelled to create the possibility of eliminating the changes reported?

Authors' reply. Uncertainty was quantified generally in the study by estimating upper and lower bounds as well as central estimates for all input parameters. Estimates were first made by the relevant expert in that field and were then adapted by the RASP team to suit parameters of the RASP model. Upper and lower bound estimates were made by experts for: