Wave Energy Resources in the Cape Verde Islands at the End of the 21st Century

The Cape Verde archipelago has potential for wave energy exploitation, but climate-change effects remain poorly understood. Future changes were assessed by comparing 1980–2005 and 2075–2100 using high-resolution Simulating WAves Nearshore (SWAN) simulations forced by winds from the Coordinated Regional Climate Downscaling Experiment for Africa and WAVEWATCH III spectral boundaries derived from EC-Earth under Representative Concentration Pathway 8.5 (RCP8.5). Validation against ESA Climate Change Initiative Sea State altimeter data indicated underestimation of monthly mean significant wave height (bias −0.19 m; root mean square error 0.41 m). Results show a marked seasonal cycle, with the largest wave heights, energy periods and wave power in winter and spring, and the highest resources in the northwestern and western sectors. Within this realization, mean wave power decreases by 6.8–7.8% at five reference points, with 95% confidence intervals excluding zero. Maximum mean wave power decreases from approximately 14.2 to 13.1 kW/m. Changes in upper-tail statistics and annual maxima are less consistent and generally indistinguishable from zero. The northern sector remains dominant, with mean direction changes below 2°. Sensitivity tests indicate greater effects of wave height and energy period uncertainty on absolute power than on the relative climate signal. Results are conditional on the selected modelling chain and high-emission scenario.