t =8,6 hoiirs. But for the development of fully arisen storm 

 waves, fetches of x > 1000 km are necessary. Thus, example 4 (Table 

 10) shows that at v = 20 m/sec (about 8 to 9 Beaufort) the minimum 

 fetch for the generation of complex sea is x = 1050 km or nearly 

 600 nautical miles; at v = 24 m/sec (example 5) x^ = l800 km or 

 about 1000 nautical miles. 



These computed fetches are in agreement with the statements of 

 experienced wave and sea observers (V. Cornish, Graf von Larisch). 

 V. Cornish estimates the minimum fetch for the generation of fully 

 arisen "storm waves" to be about 600 to 1000 nautical miles (see 

 H. Thorade [22], page 293). If the wind blows constantly, the du- 

 ration t for developing these storm waves would be at v = 20 m/sec, 



t =1.5 days (t_ = 35*6 hours); and at v = 24 m/sec, it would take 

 mm ' ' 



t^ = 2.2 days (t^^^ = 51.8 hours). 



Furthermore, the examples represented in Table 10 show that 

 the development of complex sea after the generation of flilly arisen 

 p -waves continues relatively quickly. It has already been stated 

 in Chapter I that the observations at sea indicate a rapid develop- 

 ment of longer waves at the rough sea surface when the fetches ex- 

 ceed certain minimum stretches. Under these conditions character- 

 istic interference patterns of complex wave motion emerged as the 

 striking features of the sea. 



To get an idea of the results of the theoretical computation, 

 conditions at a constant wind velocity of v = l6 m/sec are considered 

 in more detail. The application of the presented graphs and tables 

 leads to the following characteristics of complex sea generation 

 at this wind velocity: The first dominating wave (p -wave) appears 



111 



