Model Description
WAVEWATCH III® (Tolman 1997, 1999a, 2009) is a third generation wave model developed at NOAA/NCEP in the spirit of the WAM model (WAMDIG 1988, Komen et al. 1994). It is a further development of the model WAVEWATCH, as developed at Delft University of Technology (Tolman 1989, 1991a) and WAVEWATCH II, developed at NASA, Goddard Space Flight Center (e.g., Tolman 1992). WAVEWATCH III®, however, differs from its predecessors in many important points such as the governing equations, the model structure, the numerical methods and the physical parameterizations. Furthermore, with model version 3.14, WAVEWATCH III® is evolving from a wave model into a wave modeling framework, which allows for easy development of additional physical and numerical approaches to wave modeling.
WAVEWATCH III® solves the random phase spectral action density balance equation for wavenumber-direction spectra. The implicit assumption of this equation is that properties of medium (water depth and current) as well as the wave field itself vary on time and space scales that are much larger than the variation scales of a single wave. With version 3.14 some source term options for extremely shallow water (surf zone) have been included, as well as wetting and drying of grid points. Whereas the surf-zone physics implemented so far are still fairly rudimentary, it does imply that the wave model can now be applied to arbitrary shallow water.
Model Development
The model is subject to continuous development. The following new features are presently being incorporated in WAVEWATCH III® at NCEP and by our partners, or are considered for incorporation in the future.
- Unifying Cartesian and spherical grid approaches, and expanding to curvilinear grids (NRL Stennis).
- Unstructured grid options (developed at SHOM, method of Aron Roland).
- Relocatable grids in mosaic approach (NCEP).
- Alternative propagation schemes (second order scheme from MetOffice).
- Expanded list of output parameters, particularly for model coupling.
- ESMF wrapper to facilitate model coupling (NRL Stennis),
- Alternative source term parameterizations (many from NOPP projects and others).
- New GSE alleviation (NCEP).
- Quasi-steady model integration compatable with SWAN approach (NCEP).
