General Oceanography
Name_________________
Geology 105
Expedition #19 Where the Water Goes!
See Due Date in Greensheet or in Module Area of Canvas
Expedition Objective:
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Learn about the connection between deep water circulation in the ocean and the
surface circulation and how both influence long-term climate change
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Remember to answer the questions below and take notes
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Required learning group discussion instructions at the end of this worksheet
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To begin, go to: http://oceansjsu.com/105d/exped_water/1.html
We will now look at the global conveyor belt, a combination of deep (thermohaline)
circulation and surface, wind-driven circulation that transports heat through the oceans
causing major climatic effects on a time-scale of decades, centuries and millennia.
1. Combining Surface Circulation with Deep Circulation - the Global Conveyor Belt
What influences and driving forces are behind circulation of the deep waters?
2. Influence of the Conveyor Belt
How does the global conveyor influence life on our planet?
3. Tracking Deep Ocean Current – Let’s Deploy Argo Floats
Describe three ways that you will use to track the flow of deep water
(thermohaline) circulation
a.
b.
c.
4. Let's Ride the Global Conveyor Belt
Using the methods described on the previous problem, let’s track the pattern of
deep and surface circulation.
Here you see a fourth method for tracking deep water movement, what property is
being used as a tracer in this example?
_______________________________________
You will return to the map on the following page throughout the remainder of the expedition
as you draw the flow of the ocean global conveyor belt on the next page.
Based on your research during the rest of the expedition, use the
map below and different colored pencils for warm surface currents (orange or
red) and the cold, salty deep currents (blue or purple) to track the flow with
arrows of the global conveyor belt through the global ocean.
Global Map
Why does the ocean have a high salinity in the North Atlantic?
Draw on the global map, the flow of the Gulf Stream into the north Atlantic and
into the Norwegian-Greenland Sea and also the flow of high salinity water out of the
Mediterranean Sea.
5. Mischief in the Norwegian-Greenland Sea
How might the sinking of North Atlantic Deep Water (NADW) in the NorwegianGreenland Sea influence the global climate?
Make a diagram of the flow of "warm, salty" water into the North Atlantic and the
sinking of cold, salty, oxygen-rich water in the Norwegian-Greenland Sea
Equator
0
meters
Greenland
Sea Surface
Seafloor
Water
Depth
4000
meters
Seafloor
If the ice mass in Greenland continues to melt (see audio clip), how might this
influence the salinity of the ocean water in the Norwegian-Greenland Sea, and how
might this influence the ability of surface water to sink, and thereby the global
conveyor belt?
6. Into the South Atlantic - remember to show the flow of water into the south
Atlantic on the global map from both the north and south
Use the diagram below to show how oxygen-rich deep water is provided to the south
Atlantic? Label the NADW and AABW water masses.
Antarctica
Sea Surface
Equator
Greenland
0
meters
Water
Depth
4000
meters
Seafloor
Surface
900
00
Latitude
90 0
7. Into the Indian Ocean - remember to show the flow of deep water into the Indian
Ocean on the global map
What happens to the deep water flow of the conveyor belt in the Indian Ocean?
8. Into the South Pacific - remember to continue your diagram on the global map
Describe what happens to the flow of the conveyor belt in the Pacific Ocean.
9. Into the North Pacific - remember to continue your diagram on the global map
Where does the global conveyor belt go after mixing with intermediate and shallow
water in the north Pacific?
10. Through the Philippines and Indonesia and into the Indian Ocean - continue on your
global page (I studied this portion of the conveyor as a portion of my doctoral
work)
11. Across the Indian Ocean - continue your global map
How do surface currents (see your surface circulation map in the previous expedition)
assist in the westward flow of the conveyor belt in the Indian Ocean?
12. Back into the Atlantic Ocean - continue your global map
How does the water of the conveyor belt make its way back into the north Atlantic
Ocean?
13. Global Ocean Conveyor Belt and CO2
Watch the animation and describe the flow of surface and deep waters through the
entire cycle.
14. As we gain more knowledge, simple models often become more complex.
Explain how recent work is leading to a modification of ideas on the southward flow of
deep water in the north Atlantic.
15. Ignoring the Science and Misinterpreting Scientific Results
Explain how recent work has been misinterpreted for political means, rather than
science. http://www.npr.org/templates/story/story.php?storyId=120668812
In addition to the NPR audio segment, watch the two videos on the webpage and
take notes, which discuss recent research on the ocean and measuring
increasing global sea surface temperatures over the past two decades:
https://youtu.be/hnyX32nkYBs
https://youtu.be/wKj3niV_xUk
Watch videos on Southern Ocean Research, both of which touch on the importance
of circulation in the Southern Ocean around Antarctica
https://youtu.be/0KUQKZuhCXU
https://youtu.be/8VMSF28J9H4
Required Learning Group Discussion
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After completing this expedition, go to your learning group discussion and then post
two multiple-choice questions, post one multiple-choice question on a method used to
study the thermohaline circulation or the global ocean conveyor belt and a second
multiple-choice question on the path followed by this circulation and its influence on
climate. each with 5 potential answers (a, b, c, d, and e; do not highlight the correct
answers to your questions.
Scoring on required posting will be based on the clarity (ability to communicate in
writing) and quality (scientific insight) of the posted questions and the listings of
potential answers.
Ambiguous questions or answers, or error in writing quality, will receive point
deductions – be clear and precise.
Do not repeat a question posted previously by another student in your learning
group, which will consist of 9-10 other students.
Students will then provide feedback on the clarity and quality of the questions
posted by the student immediately above their own posting in their assigned
discussion and then answer the questions.
First student to post in a learning group receives an extra 48 hours, after deadline,
to answer the posting of the last student to post in the group by the deadline.