Abstract
Numerical wave hindcasting from surface winds provides an important source of information for wave energy resource assessment and climate research. We utilized the third-generation ocean and coastal wave models, WAVEWATCH III and SWAN (Simulating WAves Nearshore), in a system of nested grids to provide high-resolution wave parameters around the islands of Oahu, Maui, Kauai, and Hawai‘i from 1979 to 2013. The wind forcing includes the Climate Forecast System Reanalysis (CFSR) for the globe and downscaled winds by the Weather Research and Forecasting (WRF) model around the Hawaiian Islands. Measurements from 14 buoys provide validation of the hindcast across the Hawai‘i region. The hindcast reproduces the wave climate, statistical distributions, and episodic events recorded at both offshore and nearshore buoys. After validation, the sea state and wave power parameters are compiled at six sites around the islands. Two of the sites are located within the US Navy Wave Energy Test Site (WETS) offshore of the Marine Corps Base in Kaneohe, Oahu. One is collocated with a Waverider buoy at 81 m water depth, where tests will be conducted and the other at a shallower depth of 58 m is a potential site. The other 4 are potential sites at Kilauea, Pauwela, Upolu, and South Point at the north shore of Kauai, the north shore of Maui, and the north and south shores of Hawai‘i Island, respectively. The results show year-round wave activities with significant increases of wave power from the summer to the winter months accompanied by a transition from the wind waves to swells. At WETS, the analysis shows 60% of the energy resources come from conditions with significant wave height above 2 m that occur less than 25% of the time during 1979 to 2013. The diversified and persistent wave activities make WETS and the other five potential sites suitable for testing and development of wave energy convertors.