Ocean Circulation Theory

The waters of the earth are gathered in shallow, irregular, interconnecting basins. Heated by the sun and driven by the wind, the oceans circulate endlessly. The general circulation of the ocean is the persistent pattern of this flow on the scale of the basins. It is the heart and soul of physical oceanography, and the explanation and prediction of the flow from the principles of fluid dynamics is the chief goal of the physical oceanographer. Along with the pattern of the motion, the associated fields of pressure, temperature, salinity, and density are also necessary components of a complete theory for the ocean circulation since they are dynamically linked to the motion of the oceans. The physical problem posed by the general circulation of the oceans is a difficult one both experimentally and theoretically. From the point of view of theoretical fluid mechanics the difficulty springs fundamentally from the recirculating character of the circulation. The fluid is gathered into a single, though highly contorted basin. An overview of the advances made in the last decade and a half in this field. Based on an advanced graduate level course, the book represents fundamental insights into the structure of the physical theory of the large-scale dynamics of the oceans. The author has maintained throughout a blend of analytical and numerical results so as to achieve as deep a physical understanding of the dynamics of the large-scale circulations as possible. The results of the theories are compared with observations and the success or inadequacies of the theories are highlighted. Topics of particular interest are: theory of the wind-driven circulation, the thermocline, the equatorial circulation and the abyssal circulation. Much of the material - previously scattered throughout the literature - has been collated here for the first time. This book describes the advances made in the last decade and a half in the theory of ocean circulation. Based on an advanced graduate level course it represents fundamental insights into the structure of the physical theory of the large-scale dynamics of the oceans. Topics of particular interest are: theory of the wind-driven circulation, the thermocline, the equatorial circulation and the abyssal circulation. The author has attempted throughout to blend analytical and numerical results to achieve as deep a physical understanding of the dynamics of the large-scale circulations as possible. The results of the theories are compared with observations and the success or inadequacies of the theories are highlighted Front Matter....Pages I-XI Sverdrup Theory....Pages 1-23 Homogeneous Models of the Ocean Circulation....Pages 25-92 Vertical Structure: Baroclinic Quasi-Geostrophic Models....Pages 93-170 Theory of the Ventilated Thermocline....Pages 171-275 Buoyancy Forced Circulation and Cross-Gyre Flow....Pages 277-320 Equatorial Dynamics of the Thermocline: The Equatorial Undercurrent....Pages 321-377 Abyssal Circulation....Pages 379-450 Back Matter....Pages 451-455 Pressure maps of the flow in the upper ocean, such as that shown in Fig. 1.1.1 (a, Stommel et al. 1978; b, Reid 1994) indicate a large-scale clockwise circulation in the subtropical North Atlantic, i.e., in the region south of 45°N but north of a few degrees of the equator.