ensuring that the shapes found in this first, simple examination apply, as 

 hypothesized, to all directional distributions. Whole spectra then need to be 

 described in terms of these shapes and the resulting patterns examined for 

 common structure. Observed spectra need to be related to the forcing and 

 transformation mechanisms active at the present site. Further studies need to 

 be performed to see how variability in parameters relating to directional 

 spread affects other guidance regarding sea state description. These include 

 wave height distribution models, correlation of frequency- spectral structure 

 with directional structure, and models of the evolution of high-energy 

 (stormy) seas. 



264. The present results simply make it clear that such studies are 

 needed. The laboratory studies of Vincent and Briggs (1989) and Kaihatu and 

 Briggs (in preparation) demonstrated the importance of seas with directional 

 spread in shallow, bounded environments typical of Corps projects. The 

 present field studies show that such seas are normal. This introduces a new 

 and more realistic dimension in describing processes affecting coastal 

 engineering design. Results presented here are an initial foray in trying to 

 understand and quantify these processes. 



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