Visualizing Earth’s Radiative Balance:A Classroom “Jigsaw” Exploration of

Poleward Heat Transport

E. Christa FarmerHofstra University

Geology Department11 May 2012

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The Problem:• During my first

couple of years of teaching, I had trouble getting students to understand poleward heat transport

• Textbooks only tend to have diagrams like this:

2Fig. 1.4 Ocean Circulation, The Open University/Pergamon

Inspiration:

• At a 2005 NSF-sponsored workshop organized by Heather Macdonald, I learned about this:

Journal of Geoscience Education, v. 53, n. 1, January, 2005, p. 65-74

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Sawyer et al.’s “jigsaw” process:• Divide students into 4 groups (or multiples of 4 for larger classes)• Give each group a “data map”:

– Seismology– Volcanology– Geography– Geochronology

• Students answer questions about classifying tectonic plate boundaries, and reformulate their data onto different map

• Reorganize groups so that there is one student from each data group in each “plate group”

• Have students teach each other about their data• Have students consolidate their classifications into one system

involving all data • Compare classification systems: usually the “accepted” system will

develop

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5Image created by Dale Sawyer, Rice University (http://terra.rice.edu/plateboundary/)

One of the “data maps”:

6Image created by Dale Sawyer, Rice University (http://terra.rice.edu/plateboundary/)

MY idea:• Design a similar “jigsaw” exercise to help

students visualize poleward heat transport

• Utilize Earth Radiation Budget Experiment (ERBE) data and mapping capabilities provided by LDEO/IRI dataserver at http://iridl.ldeo.columbia.edu

• Publish an article about the exercise?? (Hasn’t happened yet!)

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The Maps:• Incoming Solar (Shortwave) Radiation• Absorbed Solar (Shortwave) Radiation• Outgoing Terrestrial (Longwave) Radiation

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(Bradley, 1999)

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Let’s try it! (…an abbreviated version)

• Look at the absorbed shortwave radiation data along 70°W longitude(this goes through where I am on Long Island)

• Using the color scale to identify the data values at each point, write down the values of the data at the following latitudes:80°N, 60°N, 40°N, 20°N, 0°N (equator)

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70°N

Write down values for 80°N, 60°N, 40°N, 20°N, 0°N (equator)

Part 2:

• Look at the outgoing longwave radiation data along 70°W longitude

• Using the color scale, write down the values of the data at the following latitudes:80°N, 60°N, 40°N, 20°N, 0°N (equator)

• Then, we will map the data!

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70°N

Write down values for 80°N, 60°N, 40°N, 20°N, 0°N (equator)

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Fill in the data

Plot the

values

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Notes:• You must set up the exercise by making sure students

first understand lat/lon, W/m2, how data come from satellites, and how to plot data

• Creating multiple graphs for different longitudes will emphasize the globality of the patterns

• Graphing can be done on chalkboard in small groups

• Analogies using bank accounts seem most accessible

• I don’t have any quantitative assessment of the effectiveness, but anecdotally it seems to help!

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Thanks!• For the full set of maps and student

instructions and instructor notes, please see: http://serc.carleton.edu/NAGTWorkshops/hurricanes/activities/28219.html

• Email me (GEOECF@Hofstra.edu) if you have any questions that I can’t answer now!

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