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Learning Resources
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Arctic SEAsons
Overview
This lesson was written for the 2012 Arctic Ocean Ecosystem Workshop and was inspired by the research work
conducted off the coast of Barrow, Alaska by researchers Steve Okonnen and Patricia Yager with PolarTREC
teachers Lollie Garay and Chantelle Rose. Students will
engage in a series of exercises to investigate seasonal
change in the Arctic ecosystem based on authentic
data. As researcher Patricia Yager notes, “In order to
understand change over long time spans, you need to
understand shorter time spans. The most fundamental
controls on life in the ocean are the physical properties
of water”.
Materials
• 1/4” inch graph paper
• Arctic SEAsons student data
sheet
• colored pencils
• transparency master
• blank T-S plot
• Station data sets (11 pages)
• Assessment document
• Assessment data graphs
• images
Objectives
Students will investigate seasonal oceanographic
change in the Arctic ecosystem by graphing and analyzing real data.
Lesson Preparation
• Students should have an understanding of density
through classroom discussions and hands-on inquiry
based labs. Refer to the PolarTREC website for Density
labs, for example:
http://www.polartrec.com/resources/lesson/sinkingfeeling-density-currents-lab
http://www.polartrec.com/resources/lesson/naturesdensity-column
http://www.polartrec.com/resources/lesson/sea-iceimpact
• Students should have an understanding of how to
graph data, set up plots and differentiate between
independent and dependent variables.
• Students and teachers should be aware that oceanographers create depth profiles from their data. Depth
will be plotted on the vertical axis, even though it is the
independent variable.
• When checking student graphs, it is helpful to have a
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Arctic SEAsons
Learning Resources
“master graph” on a transparency. That can be laid over the student graphs to check for
accuracy.
• It may be helpful for students to have an understanding of contour maps or bathymetry to
complete the T-S plot.
• This data was collected as a part of three separate research expeditions conducted by
Stephen Okonnen, University of Alaska Fairbanks in collaboration with Carin Ashjian, Woods
Hole Oceanographic Institution and Patricia Yager, University of Georgia at Athens.
Procedure
1. Have a discussion about seasonality in the Arctic. Seasonality is everything in the Arctic
due to the extreme changes that occur with each season.
2. Show students images of seasons in your local community as well as a summer image and
winter image of the Arctic. Compare and contrast. Discuss the causes for seasonality.
3. Discuss the interconnectedness between seasonality and biology. Biology is tightly coupled to seasonality.
4. The main biological link between density and biology in the ocean is stratification. Phytoplankton needs light. Stratification keeps the phytoplankton near the surface.
5. Show images of the Annika Maria, Healy and ground-based CTD deployment as the sources for the collected data.
6. Distribute student data sheets and graph paper.
7. Read over instructions to ensure students understand the task.
8. Explain that students will be plotting four data sets on four separate graphs. Each graph
will have two lines – one for winter data and one for summer data. These should be plotted
in different colors.
9. Review the vocabulary terms thermocline, halocline and pycnocline. Students will label
these on their graphs.
10. After the data is plotted, students will answer reflective analysis questions.
11. Students will be assessed based on completion of a Post Activity Assessment. This will include a graph of new data to analyze and reflect upon.
Extension
www.polartrec.com
http://arcticnitro.org
Assessment
1. Students will self-evaluate their graphs using the transparency master graph.
2. Teacher will assess the reflective questions using a rubric of their choice.
3. Post Activity Assessment will be given providing the opportunity for students to apply their
learning to a new situation.
Credits
PolarTREC teachers Lollie Garay and Chantelle Rose and Scientists Dr. Stephen Okonnen
and Dr. Patricia Yager. Credit should be given to the research expeditions from which the
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Arctic SEAsons
Learning Resources
data was obtained. Dr. Patricia Yager’s 2010-2012 ArcticNITRO project and Dr. Okonnen/ Dr.
Ashjian’s Collaborative Research projects: Annual Observations of the Biological and Physical Marine Environment in the Chukchi and near shore Beaufort Seas near Barrow Alaska - a
Biophysical Component of the Arctic Observing Network; and A Winter Expedition to Explore
the Biological and Physical conditions of the Bering, Chukchi and Southern Beaufort Sea.
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Arctic SEAsons
Learning Resources
National Science Education Standards (NSES)
Content Standards, Grades 5-8
Content Standard A: Science As Inquiry
a.
Abilities necessary to do scientific inquiry
b.
Understandings about scientific inquiry
Content Standard B: Physical Science
a.
Properties and changes of properties in matter
Content Standards, Grades 9-12
Content Standard A: Science As Inquiry
a.
Abilities necessary to do scientific inquiry
b.
Understandings about scientific inquiry
Content Standard B: Physical Science
b.
Structure and properties of matter
f.
Interactions of energy and matter
Content Standard F: Science In Personal and Social Perspectives
f.
Science and technology in local, national, and global challenges
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Arctic SEAsons Student Data Sheet
Name ___________________________________________
The data sets being used were collected during oceanographic winter and summer
samplings in the Chukchi Sea.
Temperature versus Depth, Salinity versus Depth Graphs
1.
2.
3.
4.
5.
6.
7.
8.
9.
Look at data sets attached. Each set of data represents an important physical
property of water.
Because this is a depth profile, the vertical axis will be the independent variable.
Plot depth on the vertical axis. The dependent variable for each graph will be on
the horizontal axes. Label each axis with a label and unit and be sure to give your
graph a title.
Round temperature and salinity values to one decimal place.
You will plot each data set on a separate sheet of graph paper.
Plot the values every 5 meters beginning with 1 meter.
Plot the winter line with blue colored pencil and the summer line with red colored
pencil.
Once the points are plotted, connect them using a colored pencil. Each graph will
have a winter and summer data line
Identify the thermocline and halocline on your graph.
Compare your graph with the Master transparency.
Temperature-Salinity Plot
1.
2.
3.
4.
5.
Obtain blank T-S plot showing contours for density.
Find temperature and salinity values for 1 meter on the plot. Mark the point
where the lines intersect.
Repeat this for the same data points used earlier for the summer data.
Connect the lines with a red colored pencil.
Repeat the process for winter data and connect with a blue colored pencil.
Density Graph
1.
2.
3.
4.
5.
Estimate the density from the T-S plot for each pair of data
Create a Data Table using this information
Graph the data on a Depth profile graph with depth on the vertical axis and
density on the horizontal axis
Identify and label the pycnocline on the graph.
Relate this to something you know! Think about the layers of density in the
ocean. Think about the layers of density in a bottle of salad dressing. How would
you mix the layers in a bottle of salad dressing? Explain what you think mixes the
layers in the ocean.
Reflective Questions
1.
2.
3.
4.
What evidence do you have that seasonal change affects water properties? Be
sure to look at all three graphs
Explain the impact temperature and salinity have on density.
Infer some environmental factors that influence these changes.
Predict what the temperature, salinity and density graphs may look like for
October.
24-August 2010 Station 22
71 37.2810 N 157 55.6840 W
z
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
T
3.90
3.89
3.89
3.88
3.87
3.79
3.66
3.54
3.52
3.60
3.69
3.77
3.88
3.99
3.98
3.87
3.79
3.85
3.88
3.59
3.14
2.61
1.92
1.25
0.33
-0.24
-0.56
-0.14
0.10
-0.00
-0.41
-0.50
-0.42
-0.33
-0.38
-0.42
-0.52
-0.65
-0.78
-0.92
-1.00
-1.09
-1.08
-1.01
-0.94
-0.95
24-November 2011 Station 61
71 37.32 N 157 55.91 W
S
29.65
29.65
29.65
29.65
29.66
29.67
29.71
29.76
29.82
29.87
29.91
29.98
30.02
30.05
30.04
30.10
30.17
30.26
30.24
30.21
30.31
30.38
30.55
30.63
30.88
31.11
31.35
31.55
31.58
31.63
31.70
31.80
31.87
31.87
31.95
31.98
32.04
32.09
32.17
32.22
32.26
32.30
32.34
32.36
32.36
32.38
sigma-t
23.54
23.54
23.54
23.54
23.55
23.57
23.61
23.66
23.71
23.74
23.77
23.81
23.84
23.86
23.85
23.90
23.96
24.03
24.01
24.02
24.13
24.23
24.41
24.51
24.76
24.97
25.18
25.32
25.34
25.39
25.46
25.54
25.60
25.59
25.66
25.68
25.73
25.78
25.85
25.90
25.94
25.96
26.00
26.01
26.02
26.03
chl
z
0.58
3
0.59
4
0.59
5
0.58
6
0.57
7
0.58
8
0.59
9
0.60
10
0.62
11
0.62
12
0.63
13
0.64
14
0.66
15
0.67
16
0.69
17
0.71
18
0.75
19
0.81
20
0.90
21
0.97
22
1.01
23
1.04
24
1.05
25
1.11
26
1.13
27
1.14
28
1.19
29
1.43
30
1.77
31
2.09
32
2.32
33
2.41
34
2.36
35
2.08
36
1.77
37
1.47
38
1.26
39
1.11
40
1.05
41
1.06
42
1.18
43
1.22
44
1.25
45
1.17
46
1.09
1.05
T
-1.75
-1.75
-1.75
-1.75
-1.75
-1.75
-1.75
-1.75
-1.75
-1.76
-1.76
-1.76
-1.76
-1.76
-1.76
-1.76
-1.76
-1.76
-1.75
-1.75
-1.75
-1.75
-1.74
-1.74
-1.74
-1.74
-1.73
-1.73
-1.73
-1.73
-1.73
-1.73
-1.73
-1.73
-1.73
-1.73
-1.69
-1.68
-1.68
-1.69
-1.69
-1.71
-1.72
-1.71
S
32.17
32.15
32.13
32.12
32.10
32.09
32.08
32.07
32.07
32.04
32.04
32.04
32.04
32.04
32.03
32.04
32.04
32.04
32.04
32.04
32.04
32.05
32.06
32.06
32.06
32.06
32.06
32.07
32.07
32.07
32.07
32.07
32.07
32.07
32.08
32.08
32.09
32.10
32.11
32.12
32.13
32.14
32.15
32.16
sigma-t
25.88
25.86
25.85
25.84
25.82
25.81
25.81
25.80
25.79
25.77
25.77
25.77
25.77
25.77
25.77
25.77
25.77
25.77
25.77
25.77
25.77
25.78
25.79
25.79
25.79
25.79
25.79
25.79
25.79
25.80
25.80
25.80
25.80
25.80
25.80
25.80
25.81
25.82
25.83
25.84
25.85
25.85
25.86
25.87
chl
0.06
0.05
0.06
0.06
0.05
0.05
0.06
0.05
0.05
0.05
0.05
0.06
0.05
0.06
0.05
0.05
0.06
0.05
0.05
0.06
0.05
0.06
0.07
0.07
0.06
0.06
0.06
0.06
0.06
0.06
0.06
0.07
0.06
0.06
0.06
0.06
0.06
0.06
0.06
0.07
0.06
0.06
0.06
0.06
Arctic SEAsons Post-Assessment
Name ___________________________________
The data provided for this activity was collected by Dr. Patricia Yager as a part of the
Arctic West Section (AWS) research expedition aboard the Polar Sea in the Chukchi Sea.
(Yager et al 2001)
1. Look at the data provided for Station 11. What do you think is occurring at Station 11?
Cite evidence.
2. What time of year would you expect to see these types of profiles? Explain why.