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WII.^ WAVES MD SWELL 

 PRINCIPLES Il\' FCRECASTIN 

 Table of Contents 



INTRODUCTIOK .... 



SURFACE WAVES IK WATER . ' 



General discussion 



Waves of very sjual] height 



Deep-water v;aveo of .aoderate and great height 



Interference of waves; short-crested waves; white caps 



E-LPIRICAL Kl\fOWLEDaE OF WIND WA^/SS .A1\;D SWELL 



Measurements of waves and swell 

 Gotiiparison of lEeasured and computed values 

 Ejnpirical relationships hetvveen vdnd and waves 



GROWTH OF WIIJD WASTES 



DECAY OF WAVES 



Waves advancing into i-egions cP calia 

 Effect of following or opposing winds 



Distance Trom which observed swell co'iies; travel tiLQe; 

 velocity of wind which produced the swell 



THE STATE OF THE SEA 



F0REGA3TIIJG OF WAVES FOR SHORT FETCHES 



FORECASTING OF SWELL 



Determination of v/ind, fetch, and duration 



Wind direction 



Wind velocity 



Fetch 



Duration of wind 

 Determination of highest wind v/aves 

 Determination of the swell 



V/av8s advancing through regions of calm 



Following or opposing winds 



Effect of follov/ing or cpnosing winds 

 Remarks on forecast 

 Example 



FORECASTING OF THE STATE OF THE SEA 



APPENDIX: WAYE3 ENTERING SHALLOW WATER: BREAI^RS -^^D SURF 



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