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ABSTRACT ACKNOWLEDGEMENTS CHAPTER 1 INTRODUCTION 1.1 Background 1.1.1 Ocean Surface Wave 1.1.2 Wave-Ice Interactions 1.1.3 Wave-Current Interactions 1.2 Objectives 1.3 Outline CHAPTER 2 PERFORMANCES OF VISCOELASTIC MODELS FOR OCEAN WAVE DISSIPATION IN ICE-COVERED REGIONS 2.1 Introduction 2.2 Methodology 2.2.1 Spectral Wave Model and Wave Dissipation in Ice 2.2.2 Wave Model Setup 2.2.3 Model Forcing 2.2.4 Wind and Wave Observations 2.3 Model Validations 2.3.1 Wind Forcing 2.3.2 Significant Wave Height 2.3.3 Peak Wave Period 2.4 Results 2.4.1 Determination of Ice Rheological Parameters 2.4.2 Comparisons of Two Viscoelastic Models for Wave Dissipation 2.4.3 Effects of Wave Scattering on Wave Propagations 2.5 Discussion 2.6 Conclusions CHAPTER 3 DEPENDENCES OF DRAG COEFFICIENT ON WIND SPEED AND WAVE STATE 3.1 Introduction 3.2 Drag Coefficient at the Sea Surface 3.3 Observational Data 3.3.1 FETCH 3.3.2 GOTEX 3.3.3 Grand Banks Experiment 3.3.4 HEXMAX 3.3 . J North Sea Experiment 3.3.6 RASEX 3.3.7 SWADE 3.3.8 WAVES 3.4 Analyses of Observational Wind Stress and Wave Data 3.4.1 Wind-speed-dependent Drag Coefficient 3.4.2 Wave-dependent Drag Coefficient 3.4.3 A New Parameterization of the Drag Coefficient 3.4.4 Assessment of Existing and New Parameterizations 3.5 Wave Simulations Using Different Drag Coefficient Parameterizations 3.5.1 Spectral Wave Model and Setup 3.5.2 Model Forcing 3.5.3 Wind and Wave Observations 3.5.4 Wave Model Results 3.6 Discussion and Conclusions CHAPTER 4 PERFORMANCES OF WAVE BREAKING PARAME-TERIZATIONS IN THE SPECTRAL WAVE MODEL 4.1 Introduction 4.2 Model Description and Depth-induced Wave Breaking Parameterizations 4.2.1 Spectral Wave Model 4.2.2 Existing Parameterizations for Depth-induced Wave Breaking 4.2.3 A New Parameterization for Depth-induced Wave Breaking 4.3 Observational Data and Methodology 4.3.1 Laboratory and Field Observations 4.3.2 Wave Model Setup 4.4 Results and Discussion 4.4.1 Performances of Six Existing Parameterizations 4.4.2 Effect of Bottom Slope and Normalized Water Depth 4.4.3 Calibration and Validation of the New Parameterization 4.5 Conclusions CHAPTER 5 WAVE-CURRENT INTERACTIONS DURING HURRI- CANES EARL AND IGOR 5.1 Introduction 5.2 The Coupled Wave-Circulation Model 5.2.1 Ocean Wave Model 5.2.2 Ocean Circulation Model 5.2.3 Model Configurations 5.3 Observational Data 5.4 Hurricanes Earl and Igor 5.5 Effects of Currents on Waves 5.5.1 Significant Wave Height 5.5.2 Peak Wave Period 5.5.3 Wave Spectra 5.5.4 Maximum Significant Wave Height 5.6 Effects of Waves on Circulations 5.6.1 Sea Level 5.6.2 Sea Surface Current 5.6.3 Sea Surface Salinity 5.6.4 Sea Surface Temperature 5.6.5 Vertical Structure of Temperature 5.7 Summary and Conclusions CHAPTER 6 CONCLUSIONS 6.1 Main Results and Their Significance 6.2 Future Work APPENDIX A STATISTICS FOR MODEL COMPARISONS APPENDIX B DEPENDENCES OF WAVE DISSIPATION ON ICE AND WAVE PROPERTIES BIBLIOGRAPHY