Shoreline Change Numerical Model 
Background 
81. The introduction of numerical models of shoreline change to applied 
coastal engineering research and practice began in the mid-1970's in England 
(Price, Tomlinson, and Willis 1973; Willis and Price 1975; Motyka and Willis 
1975) and Japan (Sasaki 1975, Sasaki and Sakuramoto 1978) and, later, in the 
United States (e.g., Perlin and Dean 1979). Although CE has sponsored devel- 
opment of numerical models of shoreline evolution (Le Mehaute and Soldate 
1980, Perlin and Dean 1983), this technology has had limited use in District 
and Division projects. 
82. GENESIS. The numerical modeling effort for this project was 
jointly carried out with ongoing shoreline change model development activities 
performed by research work units at CERC. This allowed considerably more 
resources to be applied than were available for the project alone. As prog- 
ress was made, the Sea Bright to Ocean Township modeling task became a 
detailed case study using the recently completed shoreline evolution suite of 
models called "GENESIS," for GENEralized model for SImulating Shoreline change 
(Hanson 1987, Hanson and Kraus in preparation). It is anticipated that 
GENESIS will be released for Corps-wide use in 1989. 
83. GENESIS is an integrated set of computer programs developed to cal- 
culate wave refraction and diffraction under simplified conditions, breaking 
wave height and direction, longshore sediment transport rate, and shoreline 
change. A wide range of boundary conditions, numbers and types of coastal 
structures, beachfill locations and volumes, and other common situations 
influencing shoreline change can be simulated with relatively moderate levels 
of operator effort. Input of wave conditions from an external source (as from 
data or another computer program such as RCPWAVE as in the present project) is 
also possible. 
One-line model 
84. The shoreline change model portion of GENESIS is classified as a 
"one-line" model. In one-line model theory it is assumed that beach contours 
remain parallel over the course of the simulation period. Therefore, one line 
or contour, conveniently taken as the shoreline, can be used to characterize 
beach plan-shape change. GENESIS was developed from site-specific one-line 
models that have successfully described long-term shoreline change measured at 
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