Climate Change Impact on Design Waves Using Climate Models

The significant wave height, Hs, with a return period of 100 years or the design wave height is traditionally evaluated on the basis of historical observations or simulated wave data. This work examines what can happen if the same is done on the basis of projected or futuristic wave data at a series of coastal locations along the country’s coastline. The design waves were derived at each location n on the basis of numerically simulated wave heights over two time slices of past and future. The wave model was forced by the CanESM2 regional climate model (RCM) run for a moderate warming scenario. The simulated daily values of Hs were fitted to the Generalized Pareto Distribution using the peak-over-threshold (POT) scheme, and 100-year Hs was derived separately for past and projected data at each site. The comparison of design Hs values derived as per projected data with those obtained from the historical data generally showed rise in the design Hs at most of the locations with some exceptions. The western coastal sites showed higher change than the eastern ones.