and 50, 100, 200, or 500 ft* if working in American customary units. GENESIS 

 requires no cross -shore grid spacing. The coordinate system and grid are 

 established early in the project, as all geographic information (shoreline 

 positions; locations of structures, beach fills, and river mouths; bathymetry; 

 wave input; etc.) must be referenced to the same coordinate system and datum 

 and this information may be prepared by different individuals. 



TREND OF OFFSHORE BOTTOM CONTOURS 



DISTANCE ALONGSHORE 



LONGSHORE 

 GRID SPACING 



Figure 5. Model coordinate system 



60. Discussion of input data requirements will center on Table 2 (see 

 also, Tanaka 1988). This table can also be used at the start of project 

 planning as a checklist for needed data. Only a small portion of the data 

 listed are used directly by GENESIS. The minimal information required is: 



a. Shoreline position. 



b . Waves . 



A table of factors for converting non-SI units of measurement to SI 

 (metric) units is presented on page 8. 



34 



