Extreme wave value analysis under uncertainty of climate change scenarios off Iberian Peninsula coast

Abstract

Extreme wave value analysis under uncertainty scenarios was developed to estimate wave climate characteristics at 17 stations in southwestern European coast off the Iberian Peninsula. A comprehensive wave dataset downscaled with the Wave Watch III (WWIII) model by Meteogalicia under MarRisk Project was used considering results of models from the Coupled Model Intercomparison Project 5 (CMIP5). Descriptive statistics for significant wave height (Hs), peak wave period (Tp), and mean and peak wave direction were performed for historical data (1960−2005), and for projected data in two twenty-year time periods under two Representative Concentration Pathway (RCP) scenarios (2026−2045 and 2081−2100). Hs and Tp extreme values for the study area were obtained using the Gumbel, Fréchet and Weibull probability distributions for the 10-, 50-, and 100-year return period. Obtained results showed that: historical Hs values decrease from North to South and are higher than those calculated in any of the RCPs future scenarios; mean Tp values appear to be constant in all stations; and means for peak and mean direction have higher frequency of occurrence in Q4 (270°−360°). This study also allowed the computation of Hs and Tp values for 100-year return period, which can be used as design criteria for structural analyses in maritime works