whereas for a constant wave height, an increase in wave steepness (decrease in 

 wave period) moved the bar shoreward. He noted that bars developed in the 

 laboratory experiments were shorter and more peaked than bars in the field and 

 attributed this difference to variability in the wave climate on natural 

 beaches . 



28. King and Williams (1949), in work also connected with the war 

 effort, distinguished between bars generated on nontidal beaches and bars 

 occurring on beaches with a marked tidal variation (called ridge and runnel 

 systems by them) . They assumed that nonbreaking waves moved sand shoreward 

 and broken waves moved sand seaward. Field observations from the Mediter- 

 ranean confirmed the main ideas of this conceptualization. In laboratory 

 experiments the cross -shore transport rate was measured with traps, showing a 

 maximum transport rate located around the break point. Furthermore, the term 

 "breakpoint bar" was introduced, whereas berm formations were denoted as 

 "swash bars." The slope of the berm was related to the wavelength, where a 

 longer wave period produced a more gentle slope. King and Williams hypothe- 

 sized that ridge and runnel systems were not created by breaking waves but 

 were a result of swash processes. 



29. Johnson (1949) gave an often cited review of scale effects in 

 movable bed modeling and referenced the criterion for distinguishing ordinary 

 and storm profiles discovered by Waters (1939). 



30. Shepard (1950) made profile surveys along the pier at Scripps 

 Institution of Oceanography, La Jolla, California, in 1937 and 1938, and 

 discussed the origin of troughs. He suggested that the combination of 

 plunging breakers and longshore currents was the primary cause. He also 

 showed that the trough and crest depths depended on breaker height. Large 

 bars formed somewhat seaward of the plunge point of the larger breakers , and 

 the ratios for the trough- to -crest depth were smaller than those found by 

 Keulegan (1948) in laboratory experiments. Shepard (1950) also observed the 

 time scale of beach profile response to the incident wave climate and conclud- 

 ed that the profile change was better related to the existing wave height than 

 to the greatest wave height from the preceding 5 days. 



31. Bascom (1951) studied the slope of the foreshore along the Pacific 

 coast and attempted to relate it to grain size. A larger grain size implied a 



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