Relative wave height 



(after Munk, 1949) 



Figure 2-16. Functions M and N in solitary wave theory. 



Total energy in a solitary wave is about evenly divided between kinetic 

 and potential energy. Total wave energy per unit crest width is 



8 



E =3-^ PgH^'^ d3/2 



(2-70) 



and the pressure beneath a solitary wave depends on the local fluid velocity, 

 as does the pressure under a cnoidal wave; however, it may be approximated by 



P = pg(y„ - y) 



(2-71) 



Equation (2-71) is identical to that used to approximate the pressure beneath 

 a cnoidal wave. 



As a solitary wave moves into shoaling water it eventually becomes unsta- 

 ble and breaks. McCowan (1891) assumed that a solitary wave breaks when the 



2-58 



