PART IV: FUTURE RESEARCH NEEDS 



26. The actual role of infragravity long wave energy in surf and swash 

 sediment transport is just now being addressed in observational studies. 

 Their existence and importance have been proven. Theoretical scenarios of 

 long wave generation and propagation through longshore currents and over dif- 

 ferent topographies remain to be tested in the field. Concrete answers to 

 very serious problems are needed. For instance, do infragravity motions move 

 sandbars? Do structures (i.e., breakwaters) that are built to damp and/or 

 reflect incident wind wave energy, damp or amplify infragravity energy? Is 

 infragravity energy important shoreward of breakwaters, within harbors? The 

 answers are limited by the data. 



27. Unfortunately (but understandably), researches are acutely inter- 

 ested in the dynamics of the nearshore during storm conditions when measure- 

 ments are most difficult. Recently, a series of experiments held at the 



US Army Corps of Engineers Field Research Facility (FRF) at Duck, NC (Duck-82, 

 October 1982; Duck-85, October 1985; and SUPERDUCK, October 1986), have 

 striven in part to observe nearshore dynamics under such hostile conditions. 

 The latest of the Duck experiments, SUPERDUCK, holds tremendous promise with 

 its bathymetry, infragravity, and wind wave regimes well monitored. But all 

 of these experiments are short in duration, typically only a few weeks in 

 length. Researchers consider themselves lucky to catch one storm event during 

 such efforts and unbelievably fortunate to have a well-defined morphological 

 feature develop while instruments are in place. 



28. A potentially invaluable next effort that would contribute greatly 

 to the understanding of nearshore dynamics would be a long-term observational 

 study of some of the pertinent variables. Such a study would lend insight 

 into the behavior of the nearshore through storm events and help to answer 

 questions such as, "how big is big" and "how typical is typical." A couple of 

 years ago, a long-term observational study of the nearshore would have been a 

 logistic impossibility. Such a study would need to monitor bathymetry (mor- 

 phology), incident swell and wind wave climatology, infragravity wave content, 

 and shoreline variance over months and hopefully years. However, times have 

 changed and in place today at the FRF is a daily data acquisition facility 

 that is presently monitoring most of these variables. So, the pieces are 



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