the dlmensionless sediment fall speed H/wT , in which H is the local wave 

 height, w is the sand fall speed, and T is the wave period. 



200. For an equilibrium profile developed during a storm, during which 

 a bar normally forms in the vicinity of the break point. Equation 1 is 

 expected to apply only to the portion of the surf zone shoreward of the bar, 

 where strong turbulence is present and energy dissipation is related to the 

 breaking wave height and water volume. If wave reformation occurs, several 

 areas along the profile may exist in which profile change is controlled by 

 energy dissipation per unit volume, and the profile in these areas is expected 

 to be well approximated by Equation 1. 



Criteria for Distinguishing Profile Response 



201. If a beach profile is not in equilibrium with the waves incident 

 upon it, sand will be redistributed as the beach adjusts toward equilibrium 

 shape. Depending on the wave conditions, existing profile shape, and sand 

 properties, the cross -shore sand transport rate will be predominantly directed 

 either offshore or onshore. Offshore transport results in erosion on the 

 upper part of the profile and formation of a notable bar at the break 

 point(s), whereas onshore transport leads to accretion of sand on the 

 foreshore and berm buildup. These two types of profile response forming two 

 distinctly different beach shapes are commonly known as bar/berm profiles 

 (other descriptions are: winter/summer profile, storm/normal profile, 

 erosional/accretionary profile, bar/step profile, bar/nonbarred profile, dis- 

 sipative/ref lective profile) . 



202. Criteria to distinguish bar and berm profiles have been developed 

 by various authors, and Table 3 gives a summary of several criteria developed 

 for distinguishing beach erosion and accretion or bar/berm profile response 

 which will be discussed below. Note that the criteria of Rector (1954), Dean 

 (1973), and Hattori and Kawamata (1981) originally referred to the direction 

 of cross -shore transport. 



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