Part 5 

 WAVE FORECASTS 



Introduction 



Operation SWOP came into being as a result of the establishment by 

 ONR of a research project to be organized for the purpose of determining 

 the two dimensional energy spectrum of a fully developed sea. One of the 

 unsolved problems in present wave theory is that of the directional spec- 

 trum for a given sea condition. Since a vital part of the Pier son, Neumann, 

 and James forecasting method [195 5], now being published by the Hydro- 

 graphic Office, is based on accurate knowledge of the directional spectrum, 

 the project is one of considerable importance and interest. The presently 

 assximed distribution of energy moving in the various directions in a fetch 

 area is only approximated and the subject of considerable controversy. 

 It is hoped that the successful conclusion of Operation SWOP will provide 

 the desired information and result in improving the accuracy of our present 

 wave forecasting techjiiques. 



The Division of Oceanography of the U. S. Navy Hydrographic Office 

 has participated in the project, both in selecting the site at which the oper- 

 ation was accomplished and in providing the wave forecasting service which 

 made possible the aerial-photography under the required conditions. 



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