Chapter 5: The circulation of the Oceans
The Ocean - correct answer Have high heat capacity. So, slight differences in
incoming solar radiation from place to place have little impact on surface
temperature of ocean (lateral temperature and density differ slightly).
The Ocean - correct answer Therefore, the ocean does not circulate as a direct
response to surface heating.
Wind Stress - correct answer Wind over ocean causes friction at surface --> wind-
drift currents (force of wind acting on surface).
Convergence - correct answer Water piles up (or converges) in the middle of the
gyre. This happens because of wind-driven surface-ocean currents, Earth's rotation,
and ultimately, friction. Downwelling
Divergence - correct answer Divergence can occur at the ocean surface when two
ocean currents split. Upwelling will occur at that location.
The southeast trades produce the westward-flowing South Equatorial Current and
the net Ekman Transport is to the left of the wind flow, toward the South (hence,
divergence occurs near the equator.
Important areas of divergence: off the southwest coast of North America and the
West Coast of North America due to easterly winds and southward-moving currents.
Important areas of divergence: off the west coast of South America and Southern
Africa. Where northward-moving currents have same effects.
Upwelling - correct answer The rising of cooler water to the surface to replace warm,
divergent surface water. It is rich in nutrients, and brings them to the surface.
