Eddies in marine science

1. Overview and Summary of Eddy Science.- 1.1 Eddy Currents in the Ocean.- 1.1.1 Observing the Eddies.- 1.1.2 Modeling the Eddies.- 1.2 Status of Eddy Science.- 1.2.1 Distribution and Generation.- 1.2.2 Physics.- 1.2.3 Role in the General Circulation.- 1.3 Influences of Eddies.- 1.3.1 Scientific Processes and Practical Consequences.- 1.3.2 Dispersion and Mixing.- 1.3.3 Description and Prediction.- 1.4 Evolution and Outlook.- 1.4.1 A Time of Transition.- 1.4.2 A Decade of Eddy Research.- 1.4.3 Eddies in Marine Science.- Regional Kinematics, Dynamics, and Statistics.- 2. Gulf Stream Rings.- 2.1 Introduction.- 2.2 History.- 2.3 Cold-Core Rings.- 2.3.1 Formation.- 2.3.2 Structure and Velocity.- 2.3.3 Distribution and number.- 2.3.4 Movement.- 2.3.5 Interaction and Coalescence with Gulf Stream.- 2.3.6 Decay.- 2.4 Warm-Core Rings.- 2.5 Gulf of Mexico Rings.- 2.6 Eastern Rings.- 2.7 Current Rings from Other Currents.- 3. Western North Atlantic Interior.- 3.1 Introduction.- 3.2 Observations.- 3.2.1 Spectrum and Time Scales.- 3.2.2 Spatial Scales.- 3.2.3 Kinetic and Potential Energy.- 3.3 Other Data.- 3.4 Some Simple Conclusions.- 4. The Western North Atlantic - A Lagrangian Viewpoint.- 4.1 Introduction.- 4.2 The Data Base.- 4.3 The Mean Field.- 4.3.1 The Lagrangian View.- 4.3.2 The Equivalent Eulerian View, and the Eddy Kinetic Energy Distribution.- 4.4 Mixing and Dispersion.- 4.5 Topographic Influences.- 4.6 The Eastward Flow in the Subtropical Gyre.- 4.7 Discrete Eddies.- 4.8 The Path of the Gulf Stream.- 4.9 Concluding Remarks.- 5. The Local Dynamics of Eddies in the Western North Atlantic.- 5.1 Introduction.- 5.2 Scientific Objectives.- 5.2.1 Dynamical Balances.- 5.2.2 Synoptic Structures.- 5.2.3 Geostrophic Fine Scales.- 5.2.4 Surface Layer Mesoscale Eddies.- 5.2.5 The General Circulation.- 5.3 The Experiment.- 5.4 The Phenomena.- 5.5 Summary.- 6. Gulf Stream Variability.- 6.1 Introduction.- 6.2 The Gulf Stream Path.- 6.3 Current Structure and Transport.- 6.4 Water Masses.- 6.5 Dynamics.- 6.6 Summary.- 7. The Northeast Atlantic Ocean.- 7.1 Introduction.- 7.2 General Oceanographic Conditions and Mean Circulation..- 7.3 Data Sources.- 7.3.1 Hydrographic Data.- 7.4 XBT Observations.- 7.5 Direct Observation of Currents.- 7.6 Satellite Observations.- 7.7 Surveys of Individual Eddies.- 7.8 Summary.- 8. Eddy Structure of the North Pacific Ocean.- 8.1 Introduction.- 8.2 Coastal Regions.- 8.3 Mid-Latitude Open Ocean.- 8.4 Tropical Region.- 8.5 Direct Current Measurements.- 9. Subpolar Gyres and the Arctic Ocean.- 9.1 Introduction.- 9.2 The Arctic Ocean.- 9.3 Labrador Sea and Northwestern Atlantic.- 9.4 The Norwegian and Greenland Seas and Their Overflows.- 9.5 The Northeast North Pacific and Bering Sea.- 9.6 Summary.- 10. Tropical Equatorial Regions.- 10.1 Latitudinal Changes of Mesoscale Processes.- 10.2 Eddy-Resolving Arrays in the Tropics.- 10.3 Mesoscale Features in Sections.- 10.4 Mesoscale Energy in the Tropics.- 11. Eddies in the Indian Ocean.- 11.1 Introduction.- 11.2 Kinetic Energy of the Seasonal Circulation.- 11.3 Arabian Sea.- 11.4 Somali Current.- 11.5 Bay of Bengal.- 11.6 Equatorial Zone.- 11.7 South Equatorial Current.- 11.8 Deep Currents in the Indian Ocean.- 11.9 Significance of Indian Ocean Eddies.- 12. The South Pacific Including the East Australian Current.- 12.1 Introduction: The Subtropical South Pacific.- 12.2 Observations: The Tasman Sea.- 12.2.1 The East Australian Current.- 12.2.2 The Tasman Front.- 12.3 Theories.- 12.3.1 A Line Vortex and a Wall.- 12.3.2 A Free Inertial Jet.- 12.3.3 Baroclinic Instability of a Western Boundary Flow..- 12.4 The Significance of Eddies.- 12.4.1 Physical Significance.- 12.4.2 Biological Significance.- 12.5 Future Research.- 12.5.1 The Mid-Ocean.- 12.5.2 The East Australian Current.- 13. Eddies in the Southern Indian Ocean and Agulhas Current.- 13.1 Introduction.- 13.2 South Eastern Indian Ocean.- 13.2.1 Vicinity of the South Equatorial Current.- 13.2.2 West of Australia.- 13.2.3 Vicinity of the Subtropical Convergence.- 13.3 South Western Indian Ocean.- 13.3.1 Eddies South of Madagascar.- 13.3.2 Larger Southwestern Indian Ocean.- 13.3.3 Adjacent to the Agulhas Current.- 13.3.4 The Agulhas Retroflection Area.- 13.3.5 The Vicinity of the Agulhas Plateau.- 13.4 Discussion.- 14. The Southern Ocean.- 14.1 Introduction.- 14.2 Observations of Eddies in the Southern Ocean.- 14.3 Eddy Generation and Decay.- 14.4 Effects Eddies and Implications for Models the Southern Ocean.- 15. Global Summaries and Intercomparisons: Flow Statistics from Long-Term Current Meter Moorings.- 15.1 Introduction.- 15.2 Global Kinetic Energy Estimates from Shift-Drift Analysis.- 15.3 The North Atlantic.- 15.3.1 Introduction.- 15.3.2 Ocean-Scale Patterns of Kinetic Energy.- 15.3.3 A Transect of the Western Basin.- 15.3.4 A Transect of the Eastern Basin.- 15.4 The North Pacific.- 15.4.1 The Kuroshio.- 15.4.2 Western Pacific.- 15.4.3 East-Central Pacific.- 15.4.4 Central and Eastern Tropical Pacific.- 15.5 The Equatorial Zone.- 15.6 South Atlantic.- 15.7 High Latitudes.- 15.7.1 The Antartic Circompolar Current.- 15.7.2 Weddell Sea.- 15.7.3 The West Spitsbergen Current.- 15.7.4 Arctic Ocean.- 15.8 Summary.- 15.8.1 Horizontal Distribution of Eddy Kinetic Energy at Midlatitudes.- 15.8.2 Vertical Structure of the Eddy Field at Midlatitudes.- 15.8.3 Vertical Eddy Structure in Ice-Covered Seas.- 15.8.4 Eddy Time Scales at Midlatitudes.- 15.8.5 Eddy Time Scales in the Equatorial Zone.- 15.8.6 Relationship of KE to KM Worldwide.- 16. Global Summary: Review of Eddy Phenomena as expressed in Temperature Measurements.- 16.1 Introduction.- 16.2 Standard Deviation of Temperature.- 16.3 The North and Equatorial Atlantic.- 16.4 The North and Equatorial Pacific.- 16.5 Discussion.- Models.- 17. Eddy-Resolving Numerical Models of Large-Scale Ocean Circulation.- 17.1 Introduction.- 17.2 Review of EGCM Results.- 17.2.1 What Processes Account for the Presence of Mesoscale Variability?.- 17.2.2 Do Mesoscale Phenomena Play a Fundamental Role in the Character and Dynamics of the Time-Mean Circulation?.- 17.2.3 Where the Effects of Mesoscale Circulations Are Important, Can They Be Parametrized in Terms of Mean-Field Quantities?.- 17.2.4 How Do the Answers to Questions About the Role of Mesoscale Eddies Change as the Model Physical Processes Change?.- 17.3 Comparisons with Observations.- 17.4 Unsolved Problems and Future Prospects.- 18. Periodic and Regional Models.- 18.1 Introduction.- 18.2 Two-Dimensional Turbulence.- 18.3 The Effects of ?.- 18.4 Mean Flow Generation by Localized Forcing.- 18.5 Turbulent Cascades in a Stratified Fluid.- 18.6 Scattering by Topography.- 18.7 Regional Models and Non-Local Effects.- 18.8 Comparison with Observations.- 18.9 Conclusions and Future Directions.- Effects and Applications.- 19. Eddies in Relation to Climate.- 19.1 Introduction.- 19.2 Heat Flux Carried by Eddies.- 19.3 Indirect Effects of Eddies on the Heat Balance.- 20. Eddies and Coastal Interactions.- 20.1 Introduction.- 20.2 Theoretical Considerations.- 20.2.1 Stratification, P-Effect.- 20.2.2 Abrupt Topography: Scattering and Reflection.- 20.2.3 Refractive Effects.- 20.2.4 Bottom Friction.- 20.2.5 Longshore Currents.- 20.2.6 Generating Mechanisms and Initial Value Problems.- 20.3 Observations and Analysis.- 20.3.1 The New England Continental Rise.- 20.3.2 The East Australian Shelf.- 20.3.3 The Southeastern Coast of the U.S.- 20.3.4 The West Florida Shelf.- 20.3.5 The Scotian Shelf.- 20.4 Anatomy of a Warm-Core Ring Interaction with the Continental Margin.- 20.4.1 Low-Frequency Current Data, Summer 1976.- 20.4.2 Offshore Forcing.- 20.4.3 Analysis and Interpretation.- 20.5 Conclusions.- 21. Eddy-Induced Dispersion and Mixing.- 21.1 Introduction.- 21.2 Two-Dimensional Dispersal in the Mid-Ocean.- 21.3 Streakiness.- 21.4 Particle Motions.- 21.5 Gyre-Scale Dispersal Effects.- 21.6 Tracer Evidence for Dispersal Processes.- 22. Eddies and Biological Processes.- 22.1 Introduction.- 22.2 Frontal Eddies.- 22.2.1 Formation.- 22.2.2 Air-Sea Interaction Within a Ring.- 22.2.3 Horizontal Exchanges Between the Ring and Its Surroundings.- 22.2.4 Horizontal Exchange of Plankton Between a Ring and Its Surrounding Water.- 22.3 Mid-Ocean Eddies.- 22.3.1 Biological Processes in a Single Eddy.- 22.3.2 Spatial Spectrum.- 22.4 Observational Data.- 22.4.1 Scripps Transects.- 22.4.2 Gulf Stream Ring Structures.- 22.4.3 East Australian Current Rings.- 22.4.4 Incidental Observations.- 22.5 Sampling Procedures.- 22.6 Conclusions.- 23. Eddies and Acoustics.- 23.1 Introduction.- 23.2 Dynamic Ocean.- 23.3 Sound Propagation in a Range-Dependent Environment.- 23.3.1 Geometrical Acoustics.- 23.3.2 Normal Modes.- 23.3.3 The Parabolic Approximation.- 23.4 Analytical and Numerical Studies of Sound Propagation Through Eddies.- 23.5 Acoustic Measurements in Eddies.- 23.6 Acoustic Eddy Monitoring.- 23.7 Conclusions.- 24. Instruments and Methods.- 24.1 Introduction.- 24.2 Moored Instrumentation.- 24.2.1 Moorings.- 24.2.2 Fixed Depth Moored Current Meters.- 24.3 Moored Profiling Current Meters.- 24.4 Temperature Recorders.- 24.5 Other Moored Instrumentation.- 24.6 Drifting Instruments.- 24.6.1 Surface Drifters.- 24.6.2 Deep Drifters.- 24.6.3 Problems and Interpretations.- 24.7 Profiling Instruments.- 24.7.1 Temperature and Salinity Instruments.- 24.7.2 Nansen Bottles.- 24.7.3 CTD and STD.- 24.8 Expendable Bathythermographs.- 24.9 Current Profilers.- 24.9.1 Electromagnetic Velocity Profiler.- 24.9.2 The White Horse.- 24.9.3 Schmitz-Richardson Profiler.- 24.9.4 Other Velocity Profilers.- 24.9.5 Calibration and Intercomparison.- 24.10 Remote and Inverse Techniques.- 24.10.1 Satellite and Airborne Measurements.- 24.10.2 Tomography.- 24.11 Intercomparison Between Instrument Types.- References.