122. Gourlay (1985) identified four different kinds of profile response 

 related to dominant breaker type. The dimensionless fall speed (sediment 

 mobility parameter) was decisive for describing both profile response and 

 profile geometry (Hughes and Chiu 1981). The effect of beach permeability was 

 discussed with respect to wave setup and berm height. 



123. Sallenger, Holman, and Birkemeier (1985) observed the rapid 

 response of a natural beach profile at Duck, North Carolina, to changing wave 

 conditions. Both offshore and onshore bar movement occurred at much higher 

 speeds than expected, and the ratio between trough and crest depth was 

 approximately constant during offshore bar movement but varied during onshore 

 movement. Since bars appeared to be located well within the surf zone, they 

 concluded that wave breaking was not directly responsible for bar movement. 



124. In a numerical model developed by Stive and Battjes (1985), 

 offshore sand transport was assumed to occur through the undertow and as bed 

 load only. They verified the model against laboratory measurements of profile 

 evolution produced by random waves. Stive (1987) extended the model to 

 include effects of asymmetry in the velocity field from the waves in accord- 

 ance with the transport relations of Bailard (1982). 



125. Verhagen (1985) developed a probabilistic technique for estimating 

 the risk of breakthrough of dunes during storm surge and wave action. A main 

 part of this technique was the use of a model to calculate expected dune 

 erosion during a storm (Vellinga 1983) modified by statistical distributions 

 of the factors influencing dune erosion (van de Graaff 1983, Visser 1983). 



126. Wood and Weishar (1985) made profile surveys at monthly intervals 

 on the east shore of (tideless) Lake Michigan. They found a strong temporal 

 correlation between berm undulation and the annual lake -level variation. 



127. Kriebel, Dally, and Dean (1986) studied beach recovery after storm 

 events both during laboratory and field conditions, noting the rapid process 

 of berm formation. They could not find evidence for breakpoint bars moving 

 onshore and welding onto the beach face during the recovery process; instead, 

 the berm was built from material originating farther inshore. Beach recovery 

 following the 1985 Hurricane Elena was also discussed by Kriebel (1987), who 

 concluded that the presence of a seawall did not significantly affect the 

 process of beach recovery at the site. 



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