Unstructured Mesh Generation for WaveWatch III: Global and Regional Applications

The Environmental Modeling Center's Coupled Modeling System provides the essential foundation for operational forecast systems at NOAA. WaveWatch III (WW3) is a third generation spectral wave model which is used in several center’s applications to forecast wave conditions globally and regionally. WW3’s capabilities have recently expanded to include running on unstructured meshes. Several packages can generate these meshes, including OceanMesh2D, Gmsh, and JIGSAW. This project investigates the reproducibility of various mesh generation techniques for wave modeling by employing a series of multiple regression models on a high-performance computing platform and post-processing the results to evaluate the performance of each modification in mesh refinement. A key aspect of this research is the creation of meshes specifically designed for regional modeling, which require high-fidelity mesh nearshore to accurately capture complex physical processes. These criteria include the proximity to the coastline, the gradient of the coastal bathymetry, and the number of waves that need to be accurately resolved. Furthermore, this project explores the potential advantages of renumbering nodes within the generated mesh, a technique aimed at enhancing computational efficiency and possibly reducing the computation times.Through a comprehensive series of experiments and comparative analyses, this approach aspires to establish the best practices for mesh generation in regional wave modeling. By doing so, it aims to substantially improve the operational capability and accuracy of wave forecasting models.