Overview of the various models for ice ages in the recent past (3 MYBP to present) - Ice Ages and Interglacials: Measurements, Interpretation, and Models - page 218

rather, that the actual role is more subtle than the consensus would have you
believe.

8.6.1 Glacial-interglacial cycles: the consensus view

We begin discussion of the role of the oceans in climate change with the consensus
viewpoint. This viewpoint was originated by WB in the 1980s and 1990s (see
Broecker, 2002 and Alley, 2007).
Gerhard and Harrison (2001) discussed the role of the oceans in determining
long-term climate change. According to them:

''Oceans are the single greatest influence on the distribution of heat over the
surface of the earth, by virtue of their volume, ferality, and the specific heat of
water. The world's oceans serve as a means to absorb, transport, and release large
quantities of thermal energy, and this flux exerts a major control on global
climate. The Atlantic Ocean serves as an example of the phenomenon

...

.
The oceans are effective in absorbing and transporting extremely large quantities
of thermal energy (heat) and thereby exerting a major control on global climatic
patterns.'' 1

Ocean currents now form large gyres in each of the world oceans. These gyres
move equatorial waters to the poles. Although glaciation requires cold tempera-
tures that permit ice and snow to remain over summer seasons, it also requires
massive moisture in order to provide the snow and ice necessary for maintenance
of such conditions. Some authors claimed that the flow of atmospheric moisture to
polar regions is enhanced by the oceanic circulation system that brings enough
warm moist air to the polar region to generate Northern Hemisphere snowfall. 2
A continental landmass at one polar position might be a necessary condition for
establishment of continental glaciation and icehouse conditions.
In the consensus view, the world's thermohaline circulation system is claimed
to be driven by density contrasts that result from temperature and salinity
differences. The pole-to-pole deepwater component of today's thermohaline
circulation pattern is possible because of the current locations of continental land-
masses. 3 If the positions of the landmasses change, as is known to have occurred
in the geologic past, it is logical that thermohaline-controlled heat flux will be

1 Actually, as Figure 8.5 shows, the atmosphere transports a great deal more heat than the
oceans, particularly at higher latitudes. Thus, the claim that ''Oceans are the single greatest
influence on the distribution of heat over the surface of the earth'' is simply wrong.
2 However, according to C. Wunsch (pers. commun., December 2008), ''the ocean circulation
does not provide warm moist air—the atmosphere does.''
3 However, according to C. Wunsch (pers. commun., December 2008), ''The sinking of high
latitude water does not sustain the Gulf Stream. The Stream is a wind-driven feature and a
result of the torque exerted on the ocean by the wind. It would exist even in a constant density
fluid with zero convection.''