storm event. Artificial beach nourishment was carried out during the storm to 

 prevent beach recession, and the event involved some of the highest loss rates 

 recorded. 



148. Seymour and Castel (1988) evaluated a number of cross -shore models 

 (the concept of a model taken in a very general sense), focusing on their 

 possibility of predicting transport direction. Of the models studied, the one 

 proposed by Hattori and Kawamata (1981) proved to have the highest predictive 

 capability when applying it to three different field sites. Most models were 

 not considered successful at predicting transport direction. 



149. Fenaish, Overton, and Fisher (1988) and Overton and Fisher (1988) 

 studied dune erosion induced by swash action and developed a numerical model 

 based on laboratory and field measurements. The amount of dune erosion during 

 an event was linearly related to the summation of the impact force from the 

 individual swashes. 



150. Sunamura (in press) gave a comprehensive summary of beach profile 

 morphology presenting quantitative relationships for many of the geometric 

 parameters of the beach profile. Laboratory data were mainly used to derive 

 the predictive equations. Furthermore, a descriptive model of three-dimen- 

 sional beach change was proposed consisting of eight topographic stages 

 delineated by a dimensionless quantity (breaking wave height squared to the 

 product of gravitational acceleration, median grain size, and wave period 

 squared) . 



Synthesis of Previous Work 



151. This section summarizes findings from previous work of particular 

 relevance to this study. The role of breaking waves in bar formation was 

 pointed out in pioneering field studies by Lehmann (1884), Hartnack (1924), 

 Evans (1940), King and Williams (1949), and Shepard (1950). Numerous early 

 laboratory investigations also showed that breaking waves were a main cause of 

 bar genesis, e.g.. Waters (1939), Keulegan (1948), Rector (1954), and Saville 

 (1957). Wave breaking generates turbulent motion and provides the necessary 

 mechanism for suspending and keeping sediment in suspension, thus mobilizing 

 the grains for transport by mean currents. The importance of transport as 



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