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Oceanography Learning Objectives and Study Questions
Chapter 7: Sverdrup and Kudela, 1st ed.
1. Sketch a cross section of an ocean basin that shows the salinity of water between 70°N and 70°S, and explain
why surface water has the low density near the equator, high density near 20-30° N and S, and high density
near the South Pole where sea ice is forming.
2. Sketch a graph that shows how the density of water varies with depth in typical mid-latitude ocean, and
identify the pycnocline on your graph.
3. Identify what time of year it is (summer or winter) in a mid-latitude ocean given a sketch of the shallow
thermocline and explain what factors contribute to the thermocline's observed shape.
4. Predict whether water will upwell or downwell in a region where: (1) surface currents are converging or
diverging; and (2) in a region where winds are sweeping onshore or offshore across a coastline.
5. Sketch the directions of suface currents and net transport in any part of the ocean between 60°N and 60°S
assuming that the winds driving the currents move as predicted by the planetary wind system model. Explain
why any given current flows in the direction it does with reference to the Coriolis effect and Ekman
transport.
6. Draw the direction of geostrophic flow on a map of an ocean basin between 0 and 60° N or S, and explain
why the water moves around the gyre as it does in response to gravity and the Coriolis effect.
7. Predict whether currents flowing along the eastern and western sides of an ocean basin will be stronger and
explain why.
8. Describe the conditions under which eddies form and what role they play in mixing water masses.
9. On map of Earth's oceans, locate major regions of downwelling, where surface waters sink into the deep
sea, and upwelling, where deep waters rise to the surface.
1. The most saline surface waters in an ocean basin typically occur _____.
A. astride the equator
B. between 20-30° N and S
C. at mid-latitudes 45° N and S
D. at high latitudes 60° N and S
E. over the deepest basins
2. Because of the combined effects of decreasing temperature and increasing salinity, the density of water
increases rapidly with depth across a region called the _____.
A. anticline
B. halocline
C. pycnocline
D. syncline
E. thermocline
3. Due to stirring by storms, the well-mixed layer at the top of a mid-latitude ocean is thickest during the
_____.
A. summer
B. fall
C. winter
D. spring
E. night
4. The sinking of cold, salty seawater formed below the seasonal sea ice that develops adjacent to Antarctica is
an excellent example of _____ circulation.
A. convergent
B. divergent
C. isopychnal
D. thermohaline
E. wind-driven
5. Zones of surface convergence are regions of _____.
A. exceptional productivity
B. downwelling
C. high salinity
D. low temperature
E. upwelling
6. Because of the shape of water density curves in T-S space, the mixing of two bodies of water with similar
densities but different temperatures and salinities always produces a mixture that is _____ than the original
water bodies.
A. cooler
B. denser
C. equally dense
D. less dense
E. warmer
7. Because of the Coriolis effect, the motion of surface water in the northern hemisphere is _____ the wind
direction.
A. parallel to
B. 45° to the left of
C. 90 ° to the left of
D. 45 ° to the right of
E. 90 ° to the right of
8. In the southern hemisphere, net or Ekman transport of water is _____ the wind direction.
A. parallel to
B. 45° to the left of
C. 90 ° to the left of
D. 45 ° to the right of
E. 90 ° to the right of
9. Because of the interactions of wind, the Coriolis effect, and gravity, surface currents _____ around gyres in
northern oceans.
A. flow clockwise
B. flow counterclockwise
C. flow erratically
D. reverse seasonally
E. change direction daily
10. Warm currents, like the Gulf Stream, flow towards the poles along the _____ sides of ocean basins.
A. shallow
B. deep
C. eastern
D. western
E. tectonically active
11. Because of Earth’s rotation and several related effects, currents are strongest on the _____ sides of ocean
basins.
A. eastern
B. western
C. northern
D. southern
E. deeper
12. Mixing occurs along the boundaries of water masses moving at different velocities due to the formation of
_____.
A. thermohaline circulation
B. gyres
C. Langmuir cells
D. eddies
E. Ekman transport
13. Due to seasonal wind patterns, the transport of water away from the Pacific Northwest coast in the summer
results in _____.
A. current reversals
B. downwelling
C. stronger waves
D. upwelling
E. weaker waves
14. Combined wind-driven and thermohaline circulation results in deep flow moving _____ through the Atlantic
Ocean basin.
A. northward
B. southward
C. eastward
D. westward
E. upward