TIME RANGE 



HOURS 



(ONE 



STORM) 



_■ Q 



<LUW 

 CC DC CC 

 UJ OW 



> Z& 



?2 



w 



MONTHS 

 (SEASON) 



YEARS 



1-5 



5-10 



10-20 



PROFILE CHANGE | 



(SBEACH) 



3-D 



MULTI-CONTOUR 

 LINE 











SHORELINE 

 (GENESIS) 







_i 

 < 



o 



1- 

 >• 

 _i 

 < 



z 

 < 







I— 



x o 



H m 2 



O O 2 



c H =i 



x m 2 



c/) D m 



BEACH CHANGE PREDICTION MODELS 



CLASSIFICATION BY SPATIAL AND TEMPORAL SCALES 



Figure 3. Comparison of beach change models 



Analytical models of shoreline change 



29. Analytical models are closed-form mathematical solutions of a 

 simplified differential equation for shoreline change. Because of the many 

 idealizations needed to obtain a closed -form solution, particularly the 

 requirement of constant waves in space and time, analytical models are too 

 crude for use in planning or design, except possibly in the preliminary stage 

 of project scoping. Analytical solutions serve mainly as a means to identify 

 characteristic trends in shoreline change through time and to investigate 

 basic dependencies of the change on the incident waves and the initial and 

 boundary conditions. Larson, Hanson, and Kraus (1987) have given a comprehen- 

 sive survey of more than 25 new and previously derived analytical solutions of 

 the shoreline change equation. 



21 



