CONTENTS 



Page 



CONVERSION FACTORS, U.S. CUSTOMARY TO METRIC (SI) 7 



SYMBOLS AND DEFINITIONS 8 



I INTRODUCTION 11 



1 . Hypotheses 11 



2 . General U 



II LITERATURE REVIEW 14 



1. Spectra 14 



2 . Wave Groups 18 



III FIELD WAVE DATA 20 



IV ANALYSIS PROCEDURES 27 



1 . Data Editing 27 



2— Component Frequencies, Amplitudes, and Phases 27 



3. Wave Groups 37 



V RESULTS 40 



1 . Component Amplitudes and Phases 40 



2 . Wave Groups 51 



VI INTERPRETATION 59 



VII SUMMARY 70 



LITERATURE CITED 73 



APPENDIX 



A BACKGROUND DISCUSSION OF MULTIPLE REGRESSION SCREENING (MRS) TECHNIQUE 79 



B TIME SERIES PLOTS FOR FIELD DATA AND RECOMBINED MRS CONSTITUENTS 83 



C DESCRIPTION OF COMPUTER ROUTINE FOR IDENTIFYING MAJOR PEAKS AND VALLEYS IN AN 



IRREGULAR SIGNAL 94 



D PLOTS OF PHASE VERSUS FREQUENCY FROM MRS ANALYSIS 97 



E PLOTS OF MAJOR PEAKS AND VALLEYS IN LOCAL VARIANCE TIME SERIES 105 



TABLES 



1 Location and recording information for wave gages 21 



2 Constituents used in creating artificial record 36 



3 Summary of MRS analysis from three field sites 41 



4 Grouping parameter at three field sites 52 



5 Autocorrelations between wave heights at three field sites.....' 52 



6 Autocorrelations between wave periods at three field sites 53 



7 Autocorrelations between amplitudes at three field sites 53 



8 Frequency spacing between prominent constituents from MRS analysis 63 



FIGURES 



1 Wave gage location map. South Haven, Michigan 21 



2 Wave gage location map, Columbia Light, Washington 22 



3 Wave gage location map. South Pass, Louisiana 22 



4 Time history of significant wave height and peak spectral period. South Haven 23 



