Dr. Wei-Cheng Wu

Coastal Ocean Modeling, Pacific Northwest National Laboratory

The U.S. West Coast and Alaska Coast consist of most of the U.S. wave energy resources. Wave resource characterization is an essential step for Wave Energy Converter (WEC) project siting and deployment. An accurate resource assessment requires long-term wave climate data with sufficient spatial coverage. This presentation provides an overview of a modeling effort on high-resolution, long-term wave hindcast for resource characterization in the U.S. Pacific regions. A modelling approach with nested WaveWatchIII (WW3) and unstructured-grid Simulating WAves Nearshore (SWAN) is presented. The SWAN domains cover the entire U.S. Exclusive Economic Zone (EEZ). The nearshore wave climate was simulated with SWAN at 300 m spatial resolution, driven by WW3 model output. The wave hindcasts were forced by NOAA’s global Climate Forecast System Reanalysis (CFSR) wind field at 0.5 degree spatial resolution and hourly interval. Model hindcasts cover a 32-year period from 1979 to 2010. Model configurations closely follow the International Electrotechnical Commission [IEC] Technical Specification. Model hindcasts of the six IEC recommended resource parameters were validated with extensive wave buoy data maintained by the National Data Buoy Center (NDBC) and the Coastal Data Information Program (CDIP). Model skills are assessed with a set of standard model performance metrics. The challenges of high spatial resolution simulations at regional scale, directional resolution around complex islands and high-perforce computing requirement are also addressed. The present study demonstrates that the multiscale nested-grid modeling approach with WW3 and SWAN can efficiently generate multi-decadal and high-resolution wave climate data to support accurate resource characterization at regional scales.