H { Incident wave height, m (ft) 



H^ Energy-based, or zero-moment, estimate of significant wave height, 

 m(ft) 



H s Significant wave height for wind waves and swell, m (ft) 



Hs,ion g Significant wave height for long (infragravity) waves, m (ft) 



K r Reflection coefficient of a solid boundary 



K rcoasl Reflection coefficient of a solid boundary 



L Wavelength, m (ft) 



L p Wavelength for waves at peak frequency, m (ft) 



n Unit normal vector directed into the solid region 



N D Number of HARBD computational wave directions for spectral 

 approximation 



N p Number of major peaks in wind wave and swell spectrum 



N T Number of HARBD computational wave periods for spectral 

 approximation 



r Radial polar coordinate, m (ft) 



s Directional spreading parameter 



S(f) Spectral energy density function dependent only on frequency 



S(f, 6) Spectral energy density function dependent on frequency and direction 



S(f t ) Spectral energy density at frequency,^ 



T Wave period, sec 



T p Peak spectral wave period for wind waves and swell, sec 



T p ,u,„ g Peak spectral wave period for long (infragravity) waves, sec 



u,v Horizontal velocity components, m/sec (ft/sec) 



w k Weighting factor for it'th HARBD computational frequency 



12 



Appendix I Notation 



