forces and overtopping, etc.). hydrodynamic modeling, and field data collec- 

 tion are needed. Hughes (1989) describes such an integrated, multi-tool ap- 

 proach. 



Table 2 

 Data Required for Shoreline Change Modeling 



Type of Data 

 Shoreline position 



Offshore waves 



Beach profiles 

 and bathymetry 



Structures and 

 other engineering 

 activities 



Regional transport 

 Regional geology 



Tide 



Extreme events 



Other 



Comments 



Shoreline position at regularly spaced intervals along- 

 shore by which the historic trend of beach change can 

 be determined. 



Time series or statistical summaries of offshore wave 

 height, period, and direction. 



Profiles to determine the average shape of the offshore 

 beach. Bathymetry for transforming offshore wave data 

 to values in the nearshore. 



Location, configuration, and construction schedule of 

 engineering structures (groins, jetties, detached 

 breakwaters, harbor and port breakwaters, seawalls, 

 etc.). Structure porosity, reflection, and transmis- 

 sion. Location, volume, and schedule of beach fills, 

 dredging, and sand mining. Sand bypassing rates at 

 jetties and breakwaters. 



Sediment budget; identification of littoral cells; 

 location and functioning of inlets; river discharges; 

 wind-blown sand. 



Sources and sinks of sediment; sedimentary structure; 

 grain size distribution (ambient and of beach fill); 

 regional trends in shorelin movement; subsidence; sea 

 level change. 



Tidal range; tidal datum. 



Large storms (waves, surge, beach erosion, failure of 

 structures, etc.); inlet migration, opening, or 

 closing; earthquakes. 



Wave shadowing by large land masses; strong coastal 

 currents; ice; water runoff. 



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