100 



200 



300 



Fetch, X, in kilometers 



Fig. 23, '/Vave age, 6" /v, as a function of fetch x and 

 duration (hours) after a wind of v = 16 ra/sec 

 started to blow over an undistiirbed water surface. 



By interference of the 3 -wave and the p(l)-wave, characteristic 

 variations in wave height and period occur in complex wave motion, 

 but the form of these interference phenomena is only temporary if 

 the wind continues to blow over longer fetches, because the relative 

 dimensions of the dominating waves will be changed with further 

 development of the sea. 



If the fetch is as long as x = 472 km, the "long wave" with 



116 



