Preface
VII
the density field in the thermocline and is the starting point of a
synthesis of the theories of ventilation and recirculation.
The adiabatic theories of the thermocline are extended slightly
in Chapter 5 to include the effects of heating and cooling in the
gyres as represented by specified transformations of density within
the body of the ocean. Although this a priori specification of the
heating and cooling is a weakness of the theory, the resulting
buoyancy-driven circulations form an important complement to the
purely adiabatic motions of the theories of the previous two
chapters.
Chapter 6 describes the extension of the ventilated thermocline
theory to the equator where the fundamental dynamical approximation of geostrophic balance fails. The proper continuation of the
concept of thermocline theory to the equator both automatically
provides a theory for the equatorial undercurrent, one of the most
fascinating of oceanic phenomena, and emphasizes the inescapable
dynamic link between midlatitudes and the equatorial zone.
Chapter 7 treats the abyssal circulation of the ocean. This is a
fundamental and relatively underdeveloped area of research. The
classical theory of Stommel and Arons is reviewed, and two
particularly important extensions to their theory are provided. Both
the role of large-scale topography, manifested in the great oceanic
ridge and fault systems, and the role of stratification, which is
required to explain the observed layering of the abyssal circulation,
are taken up in simple models.
My interest in the general circulation of the oceans was
rekindled after my move to Woods Hole by the presence there of
the most creative researcher in oceanography I have ever known,
Henry Stommel. He exerted his influence on the field in many ways.
Foremost, of course, was the continuing fountain of ideas and
theories which flowed from an endlessly active and fruitful
intelligence. At the same time he constantly encouraged his
colleagues to follow his example as best they could and concentrate
on coming to grips with important problems in physical oceanography. He was inspiring to work with, and it was a joy and
privilege to be his colleague. Everywhere in physical oceanography
and thus everywhere in this book the positive and benevolent
influence of his ideas ought to be clear. His central vision was that
of physical oceanography as a "hard" science. Thus he was moved
to remind us (Future Prospects for Physical Oceanography, Science
1970, val. 168, pp. 1531-1537) that, "Most physical oceanographers
will agree that the chief concern of their field is to understand the
actual hydrodynamical mechanisms at work," and "The physical
scientist does not see the ocean as a source of wealth or as a jumble
of geographic curiosities. He sees it as a hydrodynamic phenom-
VII
the density field in the thermocline and is the starting point of a
synthesis of the theories of ventilation and recirculation.
The adiabatic theories of the thermocline are extended slightly
in Chapter 5 to include the effects of heating and cooling in the
gyres as represented by specified transformations of density within
the body of the ocean. Although this a priori specification of the
heating and cooling is a weakness of the theory, the resulting
buoyancy-driven circulations form an important complement to the
purely adiabatic motions of the theories of the previous two
chapters.
Chapter 6 describes the extension of the ventilated thermocline
theory to the equator where the fundamental dynamical approximation of geostrophic balance fails. The proper continuation of the
concept of thermocline theory to the equator both automatically
provides a theory for the equatorial undercurrent, one of the most
fascinating of oceanic phenomena, and emphasizes the inescapable
dynamic link between midlatitudes and the equatorial zone.
Chapter 7 treats the abyssal circulation of the ocean. This is a
fundamental and relatively underdeveloped area of research. The
classical theory of Stommel and Arons is reviewed, and two
particularly important extensions to their theory are provided. Both
the role of large-scale topography, manifested in the great oceanic
ridge and fault systems, and the role of stratification, which is
required to explain the observed layering of the abyssal circulation,
are taken up in simple models.
My interest in the general circulation of the oceans was
rekindled after my move to Woods Hole by the presence there of
the most creative researcher in oceanography I have ever known,
Henry Stommel. He exerted his influence on the field in many ways.
Foremost, of course, was the continuing fountain of ideas and
theories which flowed from an endlessly active and fruitful
intelligence. At the same time he constantly encouraged his
colleagues to follow his example as best they could and concentrate
on coming to grips with important problems in physical oceanography. He was inspiring to work with, and it was a joy and
privilege to be his colleague. Everywhere in physical oceanography
and thus everywhere in this book the positive and benevolent
influence of his ideas ought to be clear. His central vision was that
of physical oceanography as a "hard" science. Thus he was moved
to remind us (Future Prospects for Physical Oceanography, Science
1970, val. 168, pp. 1531-1537) that, "Most physical oceanographers
will agree that the chief concern of their field is to understand the
actual hydrodynamical mechanisms at work," and "The physical
scientist does not see the ocean as a source of wealth or as a jumble
of geographic curiosities. He sees it as a hydrodynamic phenom-