Principles of terrestrial ecosystem ecology.pdf

30 2. Earth’s Climate System
60
N. Pacific Drift
30
Kuroshio
C.
30
0 0
30
60
Latitude
90
West Wind Drift
180
90 Longitude 180
90
latitudes is balanced by the upwelling of deep
water on the eastern margins of ocean basins
at lower latitudes, where along-shore surface
currents are deflected offshore by Coriolis
forces and easterly trade winds. Net poleward
movement of warm surface waters balances
the movement of cold deep water toward the
equator. Because thermohaline circulation con-
90
Humboldt C.
Gulf Stream
0
North Atlantic Drift
Figure 2.9. Major surface ocean currents. Warm currents are shown by solid arrows and cold currents by
dashed arrows. (Redrawn from Essentials of Meteorology: An Invitation to the Atmosphere, 2nd edition,
by C. Ahrens © 1998, by permission of Brooks/Cole, an imprint of the Wadsworth Group, a division of
Thomson Learning; Ahrens 1998.)
Benguela C.
0
trols latitudinal heat transport, changes in its
strength have significant effects on climate. In
addition, it transfers carbon to depth, where it
remains for centuries (see Chapter 15).
Oceans, with their high heat capacity, heat up
and cool down much less rapidly than does land
and thus have a moderating influence on the
climate of adjacent land. Wintertime tempera-
Cold salty
deep current
90
90
60
30
60
Warm shallow
current
Figure 2.10. Circulation patterns of deep and surface waters among the major ocean basins.