Download 1 Global Climate Change as a Theme for Teaching Science Lambert

Global Climate Change as a Theme for Teaching Science
Lambert, J., & Lindgren, J. Presented at the National Science Teacher
Association Conference, Baltimore, MD, 2010. http://www.coe.fau.edu/faculty/lambert/ For the past three years we have been gathering data about the knowledge and
attitudes of our preservice and inservice elementary education students regarding global
climate change (GCC), an interdisciplinary and pertinent topic for the present time in our
history. The research literature has shown that many K-12 students hold misconceptions
regarding the greenhouse effect and global warming, two conceptions essential to
understanding GCC (Mason & Santi, 1998; Rye, Rubba, & Wiesenmayer, 1997). Choi, Niyogi,
Shepardson, and Charusombat (2010) identified common alternative conceptions related to
GCC that included students confusing weather and climate; not understanding the greenhouse
effect, nor the type and source of radiation involved; and thinking that GCC is caused by holes
in the ozone layer and pollution, Students might also understand the greenhouse effect as an
environmental problem rather than a natural phenomenon (Myers & Stanisstreet, 2004).
Considering the research findings about student ideas and alternative conceptions
regarding GCC, it is important that their teachers understand the fundamental science
underlying GCC. Understanding the natural and human-induced factors affecting climate, the
potential consequences, and ways to mitigate and adapt to GCC seem especially relevant.
However, the research literature indicated that teachers’ understandings of GCC were similar to
that of K-12 students. Both inservice teachers (practicing teachers) and preservice teachers
expressed alternative conceptions such as the holes in the ozone layer causing global warming.
In one study, Summers et al. (2000) interviewed 12 elementary teachers and found only one
teacher understood the enhanced greenhouse effect as a cause of global warming. Michail,
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Stamou, and Stamou (2006) studied the environmental science knowledge of 155 elementary
school teachers and found gaps concerning acid rain, ozone depletion, and the greenhouse
effect. Papadimitriou (2004) examined climate change alternative conceptions and
misunderstandings of 172 Greek preservice elementary teachers and found the following: i.e.
confusing weather with climate; incorrectly relating climate change to environmental pollution
and acid rain; and incorrectly relating climate change to ozone layer depletion.
Our Research
As we examined our own elementary education students, both graduate and
undergraduate, we found similar misconceptions, misunderstandings and lack of knowledge of
the science behind GCC. This led to the recognition of the need for valid and reliable
assessments of the basic understandings teachers and students might have in regards to GCC
and their attitudes regarding such. We felt that increasing teachers’ knowledge about complex
climate issues was important, and saw a need for instruments that would measure and
consequently aid in the development of effective instructional programs. Our research focuses
on developing and piloting two instruments that measure elementary methods students’
(preservice and practicing teachers’) knowledge and attitudes about GCC at the beginning and
end of a science methods course, as well as developing and implementing an instructional
intervention.
Our Students and the Course
The majority of our subjects in our investigations are our undergraduate students, who are
primarily female, under the age of 27, with roughly 30% being Hispanic, African American or
Asian. Most have taken only two science courses in the biological and earth sciences. Another
smaller group consists of graduate students in a graduate elementary science methods class.
These students often are teaching at the present time while they work towards a Masters
degree.
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Curriculum and instructional materials were developed for the elementary methods
courses and included a 25-page study guide focused on understanding the science regarding
weather and GCC (available at http://www.coe.fau.edu/faculty/lambert/). The study guide was
not designed to present the content of a semester long course on GCC, but to provide teachers
with the content that a typical middle school Earth science teacher would need to understand
GCC. Some of the content in the guide includes photosynthesis and respiration, the greenhouse
effect, the reason for the seasons, the water cycle, the carbon cycle, the rock cycle, and heat
transfer. The study guide is sequenced in a way that helps students first develop an
understanding of the atmospheric composition and factors that affect weather and climate
(e.g. latitude and the seasons, heat transfer, the electromagnetic spectrum, water cycle, air
pressure and winds, ocean currents, and El Niño-Southern Oscillation). The guide explains the
greenhouse effect and how an enhanced greenhouse effect and GCC are related, followed
by the methods used to study past climates, the natural and human-induced causes, the
probable impacts, and suggestions for mitigation and adaptation. Class sessions focus on the
material in the guide and on power points that focus on visuals and graphs that aid in
understanding the issues and content. We also incorporate hands-on lessons and investigations
related to GCCE concepts. See Appendix A for examples of lessons and investigations.
There is a significant assignment, “The Climate Change Research Project,” that students
undertake and complete over a 4-6 week period. Students report the usefulness of completing
this assignment, and how it significantly increases their understanding of GCC, causes them to
reflect deeply about the issues, and relate the issues to their own lives.
We begin our instruction by having students view “An Inconvenient Truth”, the Al Gore
documentary regarding global warming. The film illustrates typical topics taught in a science
methods course (i.e., processes of science and the nature of science). Students analyze the
evidence Gore used to support his explanations of GCC in the film. Interestingly, most students
have not seen the film and are moved by the visuals and information presented in the film.
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During most viewings one could hear a pin drop as the film proceeds. The majority of students’
report increased or new interest in GCC as the result of watching the film, and many acquire the
DVD for home viewing and for repeat viewing. In a recent small intense summer class, only one
student out of 13 reported no increased interest in GCC as a result of watching the film, while
the other 12 found the documentary changed the way they viewed the world and the choices
they might make in their daily lives. They reported that they were deeply affected by the
content of the film.
Students answer questions about the science explained in the study guide and view an
updated 25-minute video segment, titled “New Thinking on the Climate Crisis,” (available at
www.ted.com). They review several websites from a carefully chosen list and discuss how they
would use these sites in their future teaching. Another question directs students to select a
country or a region of the world of particular interest and report on the conditions and problems
that the region is facing or will face due to GCC. This question requires them to use the
knowledge they have gained during climate sessions and apply it to a specific area or region of
special interest to them. At the end of the assignment and the climate sessions, students
participate in a focus group interview where they discuss their individual assignments.
The Assessment and Attitude Instruments
Two instruments have been developed to assess the knowledge of elementary methods
students regarding GCC and the science behind this issue. We call this instrument KGCC. It has
been designed to measure elementary methods students’ comprehension of the basic science
required to understand weather and climate phenomena as well as specific concepts related
to GCC. The instrument is based on the 25-page study guide. The KGCC assessment includes
four major constructs: 1) the greenhouse effect; 2) the carbon cycle; 3) causes of GCC; and 4)
consequences of GCC. (See Appendix A for sample items). Table 1 shows the 4 major constructs
and corresponding extended response items and multiple-choice item topics.
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Table 1. Relation of Items to Overall Knowledge of Global Climate Change
Construct
Construct Topic
Extended Response Items (26 – 35)
The Greenhouse
Effect
29. Explain Earth’s greenhouse effect. You
may also include a diagram with
labels.
30. What are the greenhouse gases?
The Carbon Cycle
33. Explain how the carbon cycle is
connected to global warming. You
may also include a diagram with
labels.
26. What are a few differences between
weather and climate?
27. What are a few reasons that Earth’s
climate naturally changes?
28. How do scientists study Earth’s past
climate (or) what evidence do they
use to determine past climates?
31. What do many scientists think is
causing the current warming trend?
32. What processes increase greenhouse
gases? What processes decrease
greenhouse gases?
Causes of GCC
Consequences of
GCC
34. How do the oceans affect climate on
Earth?
35. What are some potential impacts of
climate change?
Supporting Multiple-Choice Items (1-25)
Topic of Item
1. (Electromagnetic radiation)
2. (Sun’s energy)
3. (Composition of atmosphere)
4. (Difference between ozone layer and
greenhouse effect)
8. (Carbon cycle)
10. (Cellular respiration)
12. (Fossil fuels and sedimentary rocks)
9. (Photosynthesis)
10. (Cellular respiration)
11. (Role of phytoplankton)
13. (Cause of Seasons)
14. (Interpretation of seasons model)
15. (Interpretation of seasons model)
16. (Climate and angle of solar
radiation)
24. (Plate tectonics and past climates)
25. (Processes that release carbon
dioxide)
5. (Surface winds)
6. (Water cycle)
7. (Local winds)
17. (Ice and solar radiation)
18. (Coastal climate)
19. (Surface currents)
20. (Surface currents)
21. (Deep density currents)
22. (El Niño)
23. (Sea level and ice ages)
The second instrument was developed to measure elementary methods students’
attitudes toward science, the nature of science, and GCC and students’ views on the cause,
significance, and certainty of GCC. Our thought was that elementary students would develop
more positive attitudes toward science, greater interest in science, and increase their
confidence to learn science because of the many connections to the biological, physical and
earth sciences in the instructional material. This second assessment is a 25-item AGCC survey
divided into three constructs: 1) interest and confidence in learning science; 2) views on the
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nature of science; and 3) views on GCC. (See Appendix B for a sample of items on AGCC). A
statistical analysis found both instruments reliable.
Findings
Overall, elementary methods students increased in their knowledge of GCC science
after participating in the methods course. They developed more interest and confidence in
learning about GCC. In addition, the students completed the course with more positive views on
the nature of science and GCC. The students’ pre and post test scores overall increased by 30%,
a statistically significant increase. While most students could not explain the greenhouse effect
initially on the pretest, on the posttest some could partially explain the GHE and most identified
CO2 as a GHG. We found several levels of understanding in students’ responses.
Another component of the assessment probed students’ understanding of the causes of
GCC, focusing on the difference between weather and climate, how past climate is studied,
natural and human induced causes of GCC, and processes that increase and decrease
greenhouse gases. One surprising finding was some students’ confusion over weather and
climate even at the end of the course. Students might try to distinguish between weather and
climate as a local versus a regional characteristic, and most did not associate climate with
precipitation patterns, while some mentioned temperature. Another finding was that most
students did not have any ideas of how scientists study past climates before humans kept
records. The majority of students were able to identify at least one from proxy data. Further, most
students had no prior knowledge of natural causes of GCC while at the end of the course; just
over 50% of students had a partial understanding of natural causes. No students expressed a
complete understanding.
When asked what climate scientists think is causing the current warming trend, most
students could not this answer on the pretest, while most students received at least partial credit
on the posttest. There were a few alternative conceptions. First, some students thought, on the
pretest, that the warming trend was related to the ozone layer. A second alternative
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conception is related to the greenhouse effect. Approximately 10% of the students thought
greenhouse gases, such as carbon dioxide, are trapped in the atmosphere and hence causing
warming. A few said that carbon dioxide is trapped by infrared radiation – mixing up the
process.
When students were asked what processes increased and decreased greenhouse gases,
most could not list any processes on the pretest. On the post, most students had at least a partial
understanding of ways that greenhouse gases are increased and decreased. Several students
listed ways that humans could reduce the amount of greenhouse gases that were emitted
rather than actually reducing the concentration of greenhouse gases already in the
atmosphere.
Conclusions and Implications
We found our students also holding some of the same alternative conceptions identified
in the literature (i.e., confusing the kind and source of radiation involved in the greenhouse
effect, not being able to differentiate between the greenhouse effect and GCC or weather
and climate, and thinking the ozone layer is involved in GCC either by additional holes letting in
more radiation or by a build up of ozone preventing heat from exiting the atmosphere).
However, our students exhibited a few additional alternative conceptions even after instruction.
The most prevalent idea that appeared throughout student responses was that greenhouse
gases are trapped in the atmosphere instead of these gases actually being the “trappers” or
absorbers of infrared radiation. Also the DVD “An Inconvenient Truth,” appeared to cause some
students to take his explanation about the Keeling curve as literal, thinking that Earth takes one
giant breath each year.
With further analysis of the results, we will revise the multiple-choice content items and
extended response items on the KGCC assessment, and Likert-scale items on the AGCC attitude
survey items to increase reliability. Additional analysis of the extended responses will be drawn
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on to develop a multiple-choice version of these items for more widespread use. This will lead to
additional revision of the study guide and the instruction in the course. We see the need for
more work on the greenhouse effect, the carbon cycle, and air-sea interactions.
Given the short span of the intervention, the elementary methods students were able to
learn a number of specific concepts related to GCC and to develop attitudes more aligned
with the current scientific research. The majority of the elementary methods students typically
report limited knowledge of general science concepts and this is no less true for GCC. Much of
their understanding of GCC is gleaned from the media, which attempts to portray all views (and
biases) of an issue and not just the findings and investigations of climate scientists. Over the
semester, not only do the students significantly increase in knowledge of GCC, but they also
develop more interest in the issues and problems related to GCC.
Embedding an interdisciplinary theme, such as GCC, provides an opportunity to model
the processes and nature of science while also reviewing fundamental science concepts from
the earth, life and physical sciences. In order to develop effective teachers in this area, it is
important to determine the current level of knowledge teachers have in the content areas
associated with the GCC issue as well as, appropriate instructional interventions necessary to
ameliorate any knowledge shortfalls.
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References
Daskolia, M., Flogaitis, E., & Papageorgiou, E. (2006). Kindergarten teachers’ conceptual frame
on the ozone layer depletion. Exploring the associative meanings of a global
environmental issue. Journal of Science Education and Technology, 15(2), 168-178.
Dove, J. (1996). Student teacher understanding of the greenhouse effect, ozone layer depletion
and acid rain. Environmental Education Research, 2(1), 89-100.
Koulaidis, V., & Christidou, V. (1998). Models of students’ thinking concerning the greenhouse
effect and teaching implications. Science Education, 83(5), 559-576.
Mason, L., & Santi, M. (1998). Discussing the greenhouse effect: Children’s collaborative
discourse reasoning and conceptual change. Environmental Education Research, 4(1),
67-86.
Michail, S., Stamou, A. G., & Stamou, G. (2006). Greek primary school teachers’ understanding of
current environmental issues: An exploration of their environmental knowledge and
images of nature. Online at www.interscience.wiley.com, 244-259.
Mislevy, R. J. (1996) Test theory reconceived. Journal of Educational Measurement, 33, 379-416.
Papadimitriou, V. (2004). Prospective primary teachers’ understanding of climate change,
greenhouse effect, and ozone layer depletion. Journal of Science Education and
Technology, 13(2), 299-307.
Pellegrino, J.W. (2004). Complex learning environments. Connecting learning theory, instructional
design, and technology. In N.J. Seel & S. Dijkstra (Eds.) Curriculum, plans, and processes in
instructional design: International perspectives. Mahwah, NJ: Erlbaum Associates.
Rye, J. A., Rubba P. A., & Wiesenmayer, R. L. (1997). An investigation of middle school students’
alternative conceptions of global warming. International Journal of Science Education,
19, 527-551.
Summers, M, Kruger, C, Childs, A, & Mant, J. (2000). Primary school teachers’ understanding of
environmental issues: An interview study. Environmental Education Research, 6(4), 293312.
Wilson, M. (2005). Constructing Measures: An Item Response Modeling Approach. Lawrence
Erlbaum Associates, Inc. Mahwah, NJ.
Wilson M., & Bertenthal, M. W. (Eds.). (2005). Systems for State Science Assessment. Committee
on Test Design for K-12 Science Achievement, National Research Council. Washington,
DC: National Academy Press.
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Appendix A. Sample of Multiple Choice Items on Knowledge of GCC Instrument
Q2. The energy from the sun does all of the following EXCEPT _____.
a. drives density-driven currents in the atmosphere and oceans
b. provides a source of energy for the Earth’s water cycle
c. provides a source of energy for photosynthesis
d. provides a source of heat for the Earth’s interior
Q9. In addition to sunlight, which substances are needed by the leaf to carry out the process of
photosynthesis?
a. carbon dioxide and water
c. carbon dioxide and glucose
b. carbon dioxide and oxygen
d. glucose and oxygen
Q14. The diagram shows the Earth as viewed from space. The shaded area represents darkness.
Based on the diagram, which hemisphere would be having summer?
a. Eastern
c. Northern
b. Western
d. Southern
Q16. Climates near the Equator are generally warm with a small range of temperature variation
because this region _____.
a. Is usually closest to the Sun
b. Reflects the greatest amount of incoming solar radiation
c. Receives the most hours of daylight
d. Receives the most nearly perpendicular incoming solar radiation
Q17. Under the same conditions, which surface would reflect the greatest amount of solar
radiation?
a. an area of the ocean
b. an ice sheet
c. a rainforest
d. a parking lot
Q25. All of the following processes release carbon dioxide into the atmosphere EXCEPT _____.
a. Decomposition (decay) of organic matter
b. Burning of fossil fuels and forest fires
c. Photosynthesis by green plants on land and algae in water
d. Respiration by plants and animals
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Appendix B. Sample of Items on Attitude Instrument
Interest and Confidence in Science
2. I understand science concepts well enough to be effective in teaching elementary science.
3. I am interested in science.
Views on the Nature of Science
4. Today’s scientific knowledge is NOT subject to change.
7. Scientific evidence can be biased (misrepresented) in the way that it is interpreted or
reported.
11. Scientists can study things and events that happened in the past, even if no one was there to
make observations.
12. Disagreement among scientists is one weakness of science.
My Views on GCC
13. I really do NOT understand the cause of global warming.
15. Human activities are a major cause of the current warming trend.
16. The global warming over the past century, as well as weather extremes, reflects nothing
more than the climate system’s normal variability.
17. The current warming trend is occurring much faster than ever before seen in the geological
record.
19. We are already seeing signs of climate change.
20. There is a lot of disagreement among scientists on whether the planet is warming.
25. I think that potential impact of global warming is an urgent issue for the entire planet.
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