Breaking and Dissipation of Ocean Surface Waves

Cover......Page 1
BREAKING AND DISSIPATION OF OCEAN SURFACE WAVES......Page 2
Title......Page 4
Copyright......Page 5
Preface......Page 8
1 Introduction......Page 16
1.1 Wave breaking: the process that controls wave energy dissipation......Page 17
1.2 Concept of wave breaking......Page 19
2 Definitions for wave breaking......Page 27
2.1 Breaking onset......Page 28
2.2 Breaking in progress......Page 29
2.3 Residual breaking......Page 33
2.4 Classification of wave-breaking phases......Page 34
2.5 Breaking probability (frequency of occurrence)......Page 37
2.6 Dispersion relationship......Page 42
2.7 Breaking severity......Page 43
2.8 Types of breaking waves: plunging, spilling and micro-breaking......Page 55
2.9 Criteria for breaking onset......Page 57
2.10 Radiative transfer equation......Page 62
3 Detection and measurement of wave breaking......Page 64
3.1 Early observations of wave breaking, and measurements of whitecap coverage of ocean surface......Page 65
3.2 Traditional means (visual observations)......Page 74
3.3 Contact measurements......Page 78
3.4 Laboratory measurements in deterministic wave fields......Page 84
3.5 Acoustic methods......Page 89
3.6 Remote sensing (radar, optical and infrared techniques)......Page 108
3.7 Analytical methods of detecting breaking events in surface elevation records......Page 113
3.8 Statistical methods for quantifying breaking probability and dissipation......Page 127
4 Fully nonlinear analytical theories for surface waves and numerical simulations of wave breaking......Page 133
4.1 Free surface at the wave breaking......Page 135
4.1.1 Simulating the evolution of nonlinear waves to breaking......Page 139
4.1.2 Simulation of the breaking onset......Page 149
4.1.3 Influence of wind and initial steepness......Page 151
4.2 Lagrangian nonlinear models......Page 154
5 Wave-breaking probability......Page 157
5.1 Initially monochromatic waves......Page 158
5.1.1 Evolution of nonlinear waves to breaking......Page 163
5.1.2 Measurement of the breaking onset; limiting steepness at breaking......Page 165
5.1.3 Laboratory investigation of wind influence......Page 176
5.1.4 Distance to the breaking......Page 180
5.2 Wave-breaking threshold......Page 183
5.3 Spectral waves......Page 190
5.3.1 Breaking probability of dominant waves......Page 191
5.3.2 Breaking probability of small-scale waves......Page 197
5.3.3 Breaking in directional wave fields......Page 214
5.3.4 Wind-forcing effects, and breaking threshold in terms of wind speed......Page 222
6 Wave-breaking severity......Page 234
6.1 Loss of energy by an initially monochromatic steep wave......Page 235
6.2 Dependence of the breaking severity on wave field spectral properties......Page 242
7 Energy dissipation across the wave spectrum......Page 247
7.1 Theories of breaking dissipation......Page 248
7.1.1 Probability, quasi-saturated and whitecap models......Page 249
7.1.2 Kinetic-dynamic model......Page 252
7.2 Simulating the wave dissipation in phase-resolvent models......Page 253
7.3 Measurements of the wave dissipation of spectral waves......Page 261
7.3.1 Laboratory measurements......Page 262
7.3.2 Difference in the spectral distribution of dissipation due to different types of breaking mechanisms......Page 265
7.3.3 Field measurements......Page 267
7.3.4 Cumulative effect......Page 278
7.3.5 Whitecapping dissipation at extreme wind forcing......Page 280
7.3.6 Directional distribution of the whitecapping dissipation......Page 284
7.4 Whitecapping dissipation functions in spectral models for wave forecasting......Page 287
7.5 Non-breaking spectral dissipation......Page 310
8 Non-dissipative effects of breaking on the wave field......Page 337
8.1 Spectral peak downshift due to wave breaking......Page 338
8.2 Role of wave breaking in maintaining the level of the spectrum tail......Page 342
8.3 Wind-input enhancement due to wave breaking......Page 348
9.1 Atmospheric boundary layer......Page 365
9.1.1 Sea-drag dependence on wave breaking......Page 367
9.1.2 Generation of spray......Page 375
9.1.3 Boundary layer at extreme breaking......Page 386
9.2 Upper-ocean mixing......Page 390
9.2.1 Transfer of energy and momentum from the wind to the ocean......Page 391
9.2.2 Generation of turbulence......Page 399
9.2.3 Injecting the bubbles; gas exchange across the surface......Page 411
10 Conclusions. What else do we need to know about wave breaking?......Page 420
References......Page 10
Index......Page 441