It may be called to the user's mind that these results refer 

 to pure "wind sea" which is under the influence of a steady wind. 

 In practical wave forecasts, intervening "dead sea" or swell has 

 to be taken into account, if necessary. It may be mentioned in 

 this connection, that the estimates of the decay of the waves require 

 a consideration of the turbulent state of the sea surface layers. 

 For similar conditions with respect to air resistance, the decay of 

 the waves (including swell) is different depending on whether these 

 waves travel through a calm region of the ocean with a smooth sea 

 surface or whether they have to cross storm areas where heavily 

 breaking wind-generated seas and a considerable state of turbulence 

 are to be expected. 



is to be expected that the results of this report will not be 

 changed essentially by taking this slightly changed empirical 

 relationship between the steepness and the ages of the waves, 

 but the discontinuities at about p = I/3 may disappear (see 

 the remarks on page 79). In the following report on methods of 

 practical wave forecasting, this slightly changed empirical 

 relationship can be taken into account, 



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