The line for H^/L^ = 0.01 is simply followed to the left to the intersection with h/L^ = 

 0.0260. At this intersection, 



=^ = 0.0119 



Lo 



H = (0.0119) (1152) = 13,71 ft 

 a = 17° 



The second part of the example requires the breaking depth, height and angle. For this, the 

 H^/L^ = 0.01 curve intersects the breaking curve at: 



= 0.0190 



B 



therefore 



^B 



7^ = 0.0147 



Lo 



a^ = 17< 



therefore 



Hg = 0.0147(1152) = 16.9 ft 



hg = 0.0190(1152) = 21.9 ft 



Example 6-b 



Suppose that a wave is observed in transitional depths and it is desired to determine the 

 height at deep water ^ breaking, or any depth of interest. For this example, the values 

 of H/Lp and h/L^ are calculated from the observed wave height and period and water 

 depth. If the observed direction corresponds to one of the graphs available, then one 

 proceeds as before in Example 6-a. If the observed point is not in actordance with any of 

 the graphs available, then an interpolative procedure is required. As an example, consider 

 the following observed wave characteristics 



H = 20 ft 



h = 60 ft 



T = 12 sec 



a = 11" 



85 



