Climate and Biodiversity - Environmental Science - page 80

Arctic
Circle

Tropic of
Cancer

C

cu

urrent

South equatorial current

al

at

Tropic of
Capricorn

win d drif t

West w

Antarctic
Circle

Polar (ice) Highland Warm ocean current

Subarctic (snow) Cool temperate River

Warm temperate Dry Tropical Major upwelling zones Cold ocean current

Active Figure 5-2 Natural capital: generalized map of the earth's current climate zones, showing the major
contributing ocean currents and drifts. See an animation based on this figure and take a short quiz on the
concept.

Watch the formation of six giant convection cells and learn
more about how they affect climates at Environmental
ScienceNow.

60 ° N

Cold deserts

Westerlies

Forests

30 ° N

Northeast trades Hot deserts

Effects of Ocean Currents and Winds
on Regional Climates
Ocean currents and winds influence climate by
redistributing heat received from the sun from one
place to another.
Ocean currents also have a major effect on the climate
of different regions. The oceans absorb heat from the
air circulation patterns just described, with the bulk of
this heat being absorbed near the warm tropical areas.
This heat and differences in water density create warm
and cold ocean currents (Figure 5-2). These currents
tend to flow clockwise between the continents in the
northern hemisphere and counterclockwise in the
southern hemisphere (Figure 5-2). Driven by winds
and the earth's rotation, they redistribute heat received
from the sun from one place to another, thereby influ-

Forests

0 °

Equator

Southeast trades Hot deserts

30 ° S

Forests

Westerlies

Cold deserts 60 ° S

Figure 5-3 Natural capital: the earth's rotation deflects the
movement of the air over different parts of the earth, creating
global patterns of prevailing winds.