Global Climate Change Teaching Unit August 31, 2005

Global Climate Change Teaching Unit – August 31, 2005

By Mike Frost, KaukaunaHigh School

Title:

The Carbon Cycle, Elevated Carbon Dioxide Levels, and Low to No Carbon

Emitting Energy Alternatives.

Integrated / Infused:

Carbon dioxide emissions and renewable energy will beinfused with a unit on Photosynthesis.

Goal:

The following unit is designed to incorporate the effects of human fossil fuel

energy consumption and associated elevated carbon dioxide emissions with

photosynthesis. The unit is broken into 3 sections:

Understanding photosynthesis and the carbon cycle.
The effects of anthropogenic activities on global carbon dioxide levels.
Alternative low or no carbon dioxide emitting energy sources

Grade Level:

Ninth and tenth grade life science and biology students

Unit Rationale:

Photosynthesis is an extremely important concept for students to learn. It is also important that students understand that photosynthesis is not a process that occurs without other complicated interactions within a given ecosystem. I have organized a unit that will allow students to learn and understand the relationship between photosynthesis, the carbon cycle, fossil fuels, elevated global carbon dioxide levels, global warming, and the need for energy sources that reduce carbon dioxide emissions. I have also included some ideas in section 3 to compare and contrast the similarities between plants and photovoltaic (PV) cells in regards to converting sunlight to electrons. Plants use electrons created by solar energy to drive complex chemical reactions where PV cells can use electrons to create electricity by creating a flow of electrons.

Day 1-5: Section One-Understanding Photosynthesis and the Carbon Cycle

Objectives:

Students will learn the process of photosynthesis.
Students will understand that photosynthesis is an important part of the carbon cycle.

Wisconsin Standards:

A.12.3 Give examples that show* how partial systems*, models*, and explanations* are used to give quick and reasonable solutions that are accurate enough for basic needs.

C.12.3 Evaluate* the data collected during an investigation*, critique the data- collection procedures and results, and suggest ways to make any needed improvements

C.12.4 During investigations*, choose the best data-collection procedures and materials available, use them competently, and calculate the degree of precision of the resulting data

F.12.9 Using the science themes*, investigate* energy* systems* (related to food chains) to show* how energy is stored in food (plants and animals) and how energy is released by digestion and metabolism

F.12.10 Understand* the impact of energy* on organisms in living systems*

Sources:

I currently use Glencoe’s “Biology, Living systems” to teach photosynthesis. The

following outline is used to teach a 5-day unit from chapter 6.

Biology Living Systems. 1996.Raymond F. Oram. Mcmillan and

McGraw-Hill, Westerville, OH.

CHAPTER 6 AGENDA

1. READ Text, Chapter 6, pages 142 – 146. Do Understanding

Concepts 1 – 6, page 164 and Applying Concepts 12 – 15.

2. Begin discussion of Chapter 6 Energy for Cells – ATP. Read Lab. Ex.

13: Cell Energy.

Complete discussion of ATP and ADP. Begin power point program on Photosynthesis. DoLab. Ex. 13. Do the Analysis for homework.

Begin discussion of Photosynthesis. READ pages 152 – 161 and do Understanding Concepts 7 – 11, pages 164 –165. READ Lab Ex. 15: Influencing the Rate of Photosynthesis.

DoLab Ex. 15. Do the Analysis for homework. READ pages 147-151.

6. Go over Chapter 6 assignments. DUE .

7. Review for Chapter 6 test. STUDY.

8. TEST on Chapter 6. Test Date .

Vocabulary List

Absorption spectrum

ADP

ATP

Carotenoid

Dark reactions

Electron Transport Chain (ETC)

Grana

Light reactions

Stroma

Visible spectrum

Wavelength

Assessment: standard Chapter test will be used to assess student knowledge for the unit on photosynthesis.

Section Two

The effects of anthropogenic activities on global carbon dioxide levels.

Objectives:

Students will understand that plants are important “Carbon Sinks” in reducing atmospheric Carbon dioxide levels.
Understand what human activities emit carbon dioxide.
Describe the effect of elevated atmospheric carbon dioxide levels on plant growth.

Wisconsin Standards:

B.12.17Explain the concept of exported/imported pollution;* e.g., smokestacks, watersheds, and weather systems

B.12.20Debate the risks of producing pollutants

Sources:

1. Karnosky, D.F., D.R. Zak, K.S. Pregitzer, C.S. Awmack, J.G. Bockheim, R.E. Dickson, G.R. Hendrey, G.E. Host, J.S. King, B.J. Kopper, E.L. Kruger, M.E. Kubiske, R.L. Lindroth, W.J. Mattson, E.P. McDonald, A. Noormets, E. Oksanen, W.F.J. Parsons, K.E. Percy, G.K. Podila, D.E. Riemenschneider, P. Sharma, R.C. Thakur, A. Sober, J. Sober, W.S. Jones, S. Anttonen, E. Vapaavuori, B. Mankovska, W.E. Heilman, and J.G. Isebrands. 2003. Tropospheric O3 moderates responses of temperate hardwood forests to elevated CO2: A synthesis of molecular to ecosystem results from the Aspen FACE project. Functional Ecology 17:289-304. PDF

2. Karnosky, D.F. 2003. Impacts of elevated CO2 on forest trees and forest ecosystems: Knowledge gaps. Environment International 29:161-169.

Factors to Consider Brainstorming:

What are some effects of elevated atmospheric carbon dioxide?

Describe and explain the FACE project and have students hypothesize what trends have occurred in tree growth
List possible sources of carbon dioxide

Background Knowledge:

Atmospheric carbon dioxide levels increased from 315 ppm in 1955 to 370 ppm today (2005). Long-term observations of lake ice, tree leaf out, and tree growth (AspenFACE Home Page) have established a strong correlation between elevated carbon dioxide levels with global warming and increased photosynthetic rates in plants. The following activity is designed to look for long-term growth rate changes in trees by measuring the thickness of spaces using a tree core sample that is extracted with an increment borer. Students will collect data and create a scatter plot with a best-fit line and look for long-term trends in the thickness of the early wood (space). Students will then compare their data with measured atmospheric carbon dioxide levels form the Mauna Loa observatory.

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Materials:

Increment Borer
Ruler in mm
Graph paper
Pencil
Clip board
Tree Identification Guide
Flexible Tape Measure
Computer Lab with Internet Access
Water in Squeeze Bottle (rings and spaces are easier to see when moist)

Day 6

Select and identify a tree that is approximately 50 years or older.
Measure the circumference of the tree and record the data on the graph paper.
Calculate the amount of carbon you contribute to the atmosphere using a carbon calculator found on the following web site.

Calculate the amount of carbon dioxide that is stored in a tree and record the data on the graph paper. Use the tree carbon calculator on the following web site. Tree Carbon Calculator

Day 7

Use the increment borer to extract a core sample.
Place the tree core sample on the graph paper, mark each late wood ring (dark lines), and age the rings starting at the present year and working backwards. If the rings and spaces are difficult to see, use the squeeze bottle to apply water to the tree core sample
Write the correct year next to each one of the tree rings that have been marked on the graph paper. Start at the most recent year and work backwards.
Replace the tree core sample.

9. Measure the distance between rings in millimeters and

record the data on the graph paper next to the

corresponding year.

Day 8

10. Create a scatter plot with a trend line using Microsoft

Excel.

11. Compare your trend line with atmospheric carbon dioxide

levels from the Mauna Loa observatory. Use the following

web site to locate the data.

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12. Compare the tree growth trend line with moisture and

temperature trend lines from the National Climate Data

Center web site.

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13. Summarize your interpretation of the data and clearly state possible reasons

for unexpected variations in tree growth (approximately one-half page).

Conclusion:

There may or may not be a correlation trend between current elevated carbon dioxide levels and tree early wood growth. There are a tremendous number of variables like ozone, moisture, temperature, length of growing season, etc. that play a role in the growth rate of trees. Currently, carbon dioxide levels may not be elevated enough to increase the growth rate of trees. At the current rate at which atmospheric carbon dioxide levels are increasing, trees may noticeably accelerate their rate of growth. The question then becomes what will be the ecological impact? Will ecosystems and economies benefit from trees that have accelerated growth rates or will there be consequences such as decreased wood density and the loss of ecosystem biodiversity? Looking at core samples for increased tree growth rates in response to elevated atmospheric carbon dioxide is meant to be a long-term study. It may be one more parameter to look at as Carbon dioxide levels continue to exponentially increase.

Section Three

Alternative Low or No Carbon Dioxide Emitting Energy Sources.

Objectives:

1. Understand how a photovoltaic(PV) cell can create

electricity from solar energy.

2. Calculate that best angle for maximum power output from

a PV cell

3. Determine what would be the most efficient use for PV

cells to reduce carbon dioxide emissions.

Resources:

KEEP Activity Guide

KEEP Publications

Wisconsin K-12 Energy Education Program (KEEP)

PV Shingles solar shingle

Re-Energy.ca - Solar Electricity - Build Your Own Solar Car

Wisconsin Standards:

B.12.3 Evaluate the stability and sustainability* of ecosystems* in response to changes* in environmental conditions (see SC Life and Environmental Science)

B.12.9Evaluate ways in which technology has expanded our ability to alter

the environment and its capacity to support humans and other living

organisms

D.12.1 Identify a variety of approaches to environmental issues,* evaluate the consequences of each, and select and defend a position

D.12.2Evaluate reasons for participation or nonparticipation in an environmental activity in the home, school, or community

E.12.3 Take action in regard to environmental issues* in the home, school, or communities

Background:

Use the lesson “The Miracle of Solar Cells” from the KEEP Energy Activity Guide to teach students how a photovoltaic cell uses solar energy to create electricity (pages D124 – D133). After students have learned the basic chemical and mechanical properties of PV cells, it is then easy to compare and contrast the similarities of photosynthetic plants ability to capture solar energy and create electrons to that of a PV cell. Discussion topics for comparison could include color of PV cells compared to green plants (why are plants green and not black), how electrons are created in each system, and how PV cells and photosynthetic plants utilize the electrons, etc.

Day 9

Use the lesson “The Miracle of Solar Cells” from the KEEP Energy Activity Guide to teach students how a photovoltaic cell uses solar energy to create electricity (pages D124 – D133).

Day 10 and 11

Follow the directions for building a solar car (Re-Energy.ca - Solar Electricity - Build Your Own Solar Car). I modified the activity by using solar shingles instead of PV cells. (See the Web link PV Shingles solar shingle) I feel students could see and understand how photovoltaic technology could be incorporated into home construction.

Conclusion:

Students will see and understand that sufficient energy can be captured from the sun without the need for fossil fuels. Fossil fuel emissions emit a tremendous amount of carbon dioxide into the atmosphere along with many other pollutants. The global carbon dioxide levels have increased exponentially since 1955 and if the world population does not find alternative low or no carbon dioxide emission fuel sources the impact on the global climate will have severe implications for future generations.

Assessment:

Student assessment will be conducted by a lab write with several short discussion questions. The lab report format and grading rubric are written below.

Name______

Hr.______

Date_______

Dendrology

Lab Write Up

1. Write two hypotheses for this lab in regards to the information below. Each

hypothesis must contain a relationship and prediction.

What effect will elevated carbon dioxide levels have on the

growth rate of trees?

B. How will elevated carbon dioxide levels effect the growth rate of

hardwood and softwood trees?

2. Define global warming and list three sources of anthropogenic carbon dioxide

emissions.

3. How may global warming effect the growth rate of trees?

4. How may elevated carbon dioxide levels effect the growth rate of trees?

5. What season/ seasons is there the greatest increase in temperature and how

does the data influence your answer to question 3?

6. Write an introduction for this lab. The introduction must contain the following

information…

(Use a separate sheet of paper)

a. Background information (what do you know about carbon dioxide

levels)

- reasons for elevated carbon dioxide levels

-global impacts of elevated carbon dioxide levels

- future implications if carbon dioxide levels continue

to increase

Why was the lab/study done?

What is going to be done?

The hypothesis clearly stated

7. What data would be used to compare the results to, to see if the trend in the

growth rate of trees has changed in response to elevated carbon dioxide

levels?

8. Graph the results in Excel using a scatter plot and trend line.

(Print your results and attach)

9. What other variables could be a factor for the variances in tree growth rates?

10. Write a conclusion to this lab based on your hypothesis, results, statistical

analysis, and knowledge of global climate change due to elevated carbon

dioxide levels.

Grading Rubric:

WRITING A LAB REPORTTOTAL POINT VALUE IS 50 Pts.

(One section at a time)

TITLE (5pts.)

Does the title answer the following questions in the fewest possible words?

1. What is happening

2. To whom

3. Where

4. WhyPoints Earned____

INTRODUCTION (10pts.)

Does the introduction answer the following questions?

Why did the author undertake the study
What is the known background information
What is going to be done
Is the hypothesis clearly stated Points Earned____

MATERIALS AND METHODS (5pts.)

The materials and methods section must contain relevant information that describes when and where the experiment took place.The author must also explain the process in which the experiment was conducted. The finished product should be as easy to follow as a recipe for chocolate chip cookies. Make sure to avoid creating lists when writing the materials needed for the lab.

Points Earned____

RESULTS (5pts.)

The results must contain the data in a summarized form. The results must be free of interpretation. You must resist the temptation to explain the data or reach a conclusion. Points Earned____

DISCUSSION or Answering Discussion Questions(10pts.)

The discussion must contain the following information.

Reach conclusions about the hypothesis
Identify sources of error
Speculate upon the broader meaning…how does your research tie in with other areas of science or life.
Make suggestions for further research
Suggest improvements
Is your hypothesis supported, explain why or why not

Points Earned____

CONCLUSION (5pts.)

The conclusion must restate the hypothesis and summarize the lab report. Points Earned____

APPENDICES (10pts.)

Every lab report must contain appendices that are referred to within the written text of the report. A data table and graph are examples of two basic appendices. Points Earned____

Total points____