state of the Sea Wave Height Meters 



2 OolO - 0,70 



3 0„20 - lolO 

 U 0o40 - 1,50 



5 0,60-2,00 



6 1,10 - 2,30 



7 1,60 - 3,10 



If only 70 to 90 per cent of all observed cases are taken into con- 

 sideration observations from lightship KEB^MRNBELT would fall into the 

 following scheme: 



State of the Sea Wave Height Meters 



1 0,10 - 0,20 



2 0,20 - 0,40 



3 0,40 - 0,60 



4 0,60 - Oo90 



5 0,90 - 1,40 



6 1,40 - 1,90 



7 1,90 - 2,40 



8 2,40 - 2,80 



The mean values of these ranges approximately correspond to the 

 arithmetic mean value obtained from all wave heights reported from this 

 lightship (table 2), 



c , Representation of wave dimensions associated with different 

 states of the sea in three separate regions , - Subsequent diagrams 

 (figures 27-30) represent the relationship between wave height and 

 lengths where wave lengths were calculated from the counted wave fre- 

 quencies. Each dot represents an observation and the adjacent numbers 

 denote the estimated state of the sea, TfJhere two numbers were given 

 in the observation data, e,go5 state of sea 2-3^ the mean value (2,5) 

 is shown. 



Figure 27 represents a plot of the results of a series of ob- 

 servations made during the period 9 January to 6 April 1937, from light- 

 ship B0RKU>,Ot[FF stationed in 25 meters of water in western North Sea, 

 For tranquil states of the sea no values are plotted because observers 

 reported that reliable estimates of wave frequencies could not be made. 

 The most turbulent states of the sea did not occur during this period. 

 Entries vary from 2 to 6 of the Douglas Sea Scale, The graph indicates 

 that in general the more turbulent states of the sea occur more fre- 

 quently with increasing wave dimensions but that considerable overlapp- 

 ing of ranges of wave dimensions associated with particular states of 

 the sea is encountered. The ratios between wave height and wave length 

 (wave steepness) scatter considerably from 1:12 to 1:55 and in 20 per- 

 cent of all observations the ratio is less than 1:20. 



10 



