Scosh^k.d - Scosh^k d + 9 



C^ = 4 (19) 



8sinh k^d 



3(8cosh^k d + 1) 

 I = - 



64sinh k,d 



(20) 



and 



^3 = ^ (^" 



Refraction is described by Snail's law 



o 

 and the refraction coefficient 



/cos a 



C = / ^ 



R ' cosa 



(22) 



(23) 



where a = angle of wave with shoreline. Also, when refraction is included 

 the deepwater wave height in the above expressions should be replaced by 

 its unrefracted value. 



Finally, the point of breaking is determined by a modified form of 

 the empirical breaking criterion (eq. 8) . To adapt the formula to waves 

 approaching at an oblique angle, the bottom slope and deepwater wave 

 height are replaced by S cosa^ and Hq (cosao/cosab) ' , respectively. 

 The breaking criterion is then obtained by 



H /"H '\ ~ ' 



"b _ _, „l/7 1/7 ( o\ .^.. 



^=0.76S cos a^[j-J (24) 



^ = K^ 0.76 cos^/^ a^ 



/ H \ -1/4 -1/4 



\ o / 



K (25) 



Rewriting equation (25) using H^/H^ = KsK-^, where K5 is the shoaling co- 

 efficient yields 



K ^ = 0.76 (— 4J "^ '^ cos'^/^ a cos^^^^^ au (26) 



Equation (26) gives the form of the breaking criterion used in this study. 



28 



