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1. AGENCY USE ONLY (Leave blank) 



2. REPORT DATE 



July 1991 



3. REPORT TYPE AND DATES COVERED 



Final report 



4. TITLE AND SUBTITLE 



Wave Height Distributions in Multiple-Peaked Seas 



6. AUTHOR(S) 



Charles E. Long 



5. FUNDING NUMBERS 



Civil Works Research 

 Work Unit 32484 



7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) 



USAE Waterways Experiment Station 

 Coastal Engineering Research Center 

 3909 Halls Ferry Road 

 Vicksburg, MS 39180-6199 



8. PERFORMING ORGANIZATION 

 REPORT NUMBER 



Technical Report 

 CERC-91-7 



9. SPONSORING /MONITORING AGENCY NAME(S) AND ADDRESS(ES 



US Army Corps of Engineers 

 Washington, DC 20314-1000 



10. SPONSORING /MONITORING 

 AGENCY REPORT NUMBER 



11. SUPPLEMENTARY NOTES 



Available from National Technical Information Service, 5285 Port Royal 

 Road, Springfield, VA 22161 



12a. DISTRIBUTION /AVAILABILITY STATEMENT 



Approved for public release; distribution 

 unlimited 



12b. DISTRIBUTION CODE 



13. ABSTRACT (Maximum 200 words) 



Knowledge of distributions of heights of sea waves under realistic 

 oceanic conditions is critical to the successful design of coastal shore 

 protection projects. In this report, a simple examination is made of wave 

 height distributions in sea states characterized by energy spectra with 

 multiple peaks, i.e., having energy centered at two or more distinct 

 frequencies. Sea states with broad frequency spectra are also included 

 since such seas are composed of waves of diverse frequencies . These cases 

 violate the assumptions of unimodal, narrow spectra that are formally 

 required for the conventionally used Rayleigh distribution of wave heights 

 to apply. 



Reported here are tests of the Rayleigh and Modified Rayleigh wave 

 height distribution models. These models are compared with wave heights 



(Continued) 



U. SUBJECT TERMS 



Height distributions 

 Multimodal spectra 



Wave heights 

 Wind waves 



15. NUMBER OF PAGES 



63 



16. PRICE CODE 



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 OF REPORT 



UNCLASSIFIED 



18. SECURITY CLASSIFICATION 

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UNCLASSIFIED 



SECURITY CLASSIFICATION 

 OF ABSTRACT 



20. LIMITATION OF ABSTRACT 



NSN 7540-01-280-5500 



Standard Form 298 (Rev 2-89) 



Prescribed by ANSI Std Z39-18 

 298-102 



