Unit 5 – Migrations, Seafloor Features, and Ocean Circulation
Study Guide
This unit is composed of three parts. Complete the following study guide as assigned by Ms. Pitt. Please
answer in FULL sentences with diagrams when necessary on a separate piece of paper. This will serve as a
review and study guide for your upcoming test.
Test date: ___________
Objectives
Migration of Marine Animals
a. To identify the 3 types of tags used to monitor marine animal migrations.
b. To understand how satellites are used to monitor migrations.
c. To recognize the importance of monitoring marine animal migrations to our world.
Seafloor Features
a. Bathymetry - identify the geographical features found on the seafloor bottom.
Ocean Circulation
a. To understand the role that the oceans play in the climate of our planet.
b. To build a picture of the internal, layered structure of the world’s oceans based on the interactions of
solutions with different densities (controlled by temperature and salinity).
c. To explain the deep horizontal and vertical oceanic circulation - global conveyor belt.
d. To understand how the Coriolis Effect affects the many different types of currents in the world's oceans.
Part 1: Migrations in the Sea
Migrating Animals
1. Why do animals migrate? In response to their environment to search for food and to give birth.
2. How do scientists identify large marine mammals to distinguish individuals? By distinct markings on
their body.
3. Describe the migration pattern of the humpback whale. One example is along the east coast of US from
Nova Scotia to Carribbean. They head north during summer to feed, and south during winter to breed.
4. What is a baleen? Broom-like plates found in the mouths of some whales used to filter tiny organisms.
5. Describe the migration pattern of the gray whale. One example is along the west coast of US. They
head up to the Bering Sea during the summer to feed and down to the Baja peninsula to feed.
6. In general, why do whales migrate to warmer waters? Why to colder waters? Warmer to breed, colder to
feed.
7. Compare the migration distances of gray whales to humpback whales. Gray whales travel much further
on average.
8. Describe the physical characteristics of the leatherback turtle. Large animal, soft shell, big flippers.
9. Describe the reproduction patterns of the leatherback turtle. Lay
eggs every 2-3 years.
10. What is the black-footed albatross? Large migratory bird that soars
on currents and fly all around the Pacific.
11. What is a Sooty Shearwater? Type of migratory bird that is tracked
by satellites.
Satellites and Tracking
12. What is the Signals of Spring? Classroom project initiated by
NASA sponsorship in 2000 to afford educators and students to use
various types of Earth imagery to explain movement of animals.
13. What is an uplink? Transmitting signal sent up to a satellite.
Downlink? Transmitting signal sent down from a satellite to a
ground station.
14. What is the difference between a natural and artificial satellite? Look it up.
15. Differentiate between a polar and a geostationary satellite. Look it up.
16. Describe the difference in data collection of a polar satellite vs. a geostationary satellite. Polar satellites
orbit the Earth in 100 minutes, does this 14 X per day. Collects data from Earth’s surface like
volcanoes, polar ice, bodies of water, etc. Geostationary satellites record Earth images more often than
polar so scientists can view images with more frequency. Also, can collect data over an entire
hemisphere. Tracks weather systems.
17. What is a SPOT? What types of animals are they used for? Used with animals that breathe at surface.
18. What is a Pop-up Archival tag? What type of animals are they used for? Used with animals that do not
come to the surface often.
19. What is a SRDL? What type of animals are they used for? Large marine animals that dive to great
depths.
20. What are remote sensing satellites used for? Records radiation reflected from Earth’s surface 24 hours a
day and transmits large quantities of digital data to receivers on Earth.
21. What does a pixel represent? Shorted from the worlds picture and element, one data point that
represents a portion of Earth’s surface.
22. What was recently discovered about the movement of great white sharks in San Francisco? They travel
into San Francisco bay.
Part 2: Bathymetry – Seafloor Features
23. What type of technology do scientists use to study the seafloor? Now scientists use SONAR, but
previously they used a variety of basic tools to find various depths like plumblines
which was more similar to the method we used when doing our models.
24. Define the following terms. Also, be able to label each structure on a seafloor diagram. Look up
definitions in Lesson 6 (p. 101)
a. continental shelf
f. continental slope
b. abyssal plain
g. trench
c. mid-ocean ridge
h. seamount
d. guyot
i. abyssal hills
e. rift
j. mid-ocean ridge
Part 3: Ocean Circulation
Deep Ocean Circulation
25. What mostly affects ocean layers? density
26. What controls the density of ocean surface water? Temperature and salinity
27. What are the 3 zones of the stratified ocean? Upper (mixed or surface) layer (0-500 FEET or ), middle
layer (up to 500 METERS), bottom layer (depth depends on area of the ocean)
28. What is a pycnocline? At what range in depths is the
pycnocline? Be able to draw the profile. Rapid change in
density at about 150-500 meters
29. What is a thermocline? At what range in depths is the
thermocline? Be able to draw the profile. Rapid change in
temp at about 150-500 meters
30. What is a halocline? At what range in depths is the
halocline? Be able to draw the profile. Rapid change in
salinity at about 150-500 meters
31. What is the difference between a stable and unstable column of water? Stable column has layering where
most dense water is beneath less dense water. Unstable would be inverted.
32. What are the two types of currents and what affects them? Surface – wind and Coriolis effect. Deep -
density
33. Distinguish between isopycnal, isothermal, and isohaline water columns. Isopycnal – same density
throughout, isothermal – same temp throughout, isohaline – same salinity throughout
34. Explain the Global conveyor belt - thermohaline circulation. Deep water forms in North Atlantic as cold,
salty water sinks and moves to Indian then Pacific Ocean where water rises and warms and travels back
to Indian then Atlantic.
35. Differentiate between upwelling and downwelling
zones. Upwelling occurs at divergence zones (water
moving away from each other) and brings crucial
nutrients from the depths to the surface.
Downwelling is the opposite.
36. Explain what a surface convergence is. Does this
result in upwelling or downwelling? Look it up.
37. Explain what a surface divergence is. Does this
result in upwelling or downwelling? Look it up.
Surface Currents
38. Circle the correct direction. Due to the Coriolis
Effect water is deflected (right or left) of the driving
wind in the Northern Hemisphere and (right or left)
of the driving wind in the Southern Hemisphere.
39. Explain the Ekman Spiral (figure 9.2 might be helpful.) Surface water gets pulled by winds on the top at
a but Coriolis Effect pulls at a 90 degree angle to the wind. Basically resulting in the water moving
halfway between where the wind is pulling at the Coriolis Effect (45 deg) and has a slinky effect on the
layers beneath it. Pulls a layer beneath it at a 45, and so on and so forth as depth increases.
40. Over the depth of the spiral, the net flow of water moves at what angle to the wind? 45
41. Explain a gyre. Which way does a gyre spin in the Northern and Southern
Hemisphere? Major spirals of ocean circling currents.
42. How is the speed of currents measured? knots
43. Explain the phenomenon of western intensification. Due to the CE, left side of
gyres is stronger and narrower.
44. Define an eddie and explain what causes them. Swirls that break off a current in
the opposite direction.