Geoscience Reference
In-Depth Information
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Figure 8.4 Annual percent oxygen saturation in the (a) Atlantic along 34.5°N,
and (b) Pacific along 180°W. Contour intervals are 20% and the vertical axis is
in m. Data from the National Oceanographic Data Center World Atlas (2005).
surface at very high latitudes, but how do the upper and lower layers of the
ocean interact in the rest of the ocean? What processes lead to vertical motion
and mixing across the ocean's layers?
One large-scale vertical mixing process is known as
Ekman pumping
. As
discussed in section 8.1, surface currents within each ocean basin form anticy-
clonic gyres and the associated Ekman transport mounds water into the central
