The Greenhouse Effect
A WebQuest for 9th Grade Mathematics
Designed by:
Lisa Whitmire
Introduction Task Process Websites Evaluation
The greenhouse effect refers to the warming of
Earth by the sun. The main culprit in
the greenhouse effect is carbon dioxide.
Carbon dioxide in the atmosphere works like the panes of glass on a
greenhouse. Glass is transparent to
visible light, allowing the sun’s rays to warm Earth’s surface. But when the surface gives off excess heat,
the hot air stays in the greenhouse, which continues to keep the air warm. Similarly, carbon dioxide in the atmosphere
absorbs the sun’s infrared rays, allowing some of the excess heat to stay in
the atmosphere rather than escaping into space. How much heat is retained depends on how much carbon dioxide is
in the air. Over the last 200 years,
the amount of carbon dioxide in our atmosphere has increased, raising Earth’s
average temperature. Some scientists
predict that if global warming continues and Earth’s average temperature goes
up an additional 
to 
F, we could see a marked increase in the number of weather-related
disasters like heat waves, droughts, floods, and hurricanes.
Without a heat-trapping blanket of naturally
occurring carbon dioxide, it is believed that Earth would have an average
surface temperature of 
C, instead of its current average, 
C. There is evidence
that Mars has little carbon dioxide in its atmosphere, and its temperature
never exceeds 
C. At the other
extreme, Venus, with lots of carbon dioxide, has an average temperature of 
C.
The changes in the levels of carbon dioxide on
Earth happened naturally until 200 years ago.
During the Industrial Revolution of the early 1800s, a new factor was
thrown into the equation. When wood and
fossil fuels like coal, oil, and natural gas are burned, carbon dioxide is
released in large quantities. Oceans
and vegetation absorb the gas. But due
to the widespread cutting of trees to produce goods in the 1900s, few remained
to soak up excess carbon dioxide. In 1920,
atmospheric carbon dioxide stood at about 280 parts per million (ppm). By 1996, it had risen to 356 ppm.
Two scales are used to measure temperature. The Celsius scale, part of the metric
system, was invented in 1741 by Swedish astronomer Anders Celsius
(1701-1744). The Celsius scale has the
freezing point of water at 
C and the boiling point of water at 
C. The scale most
frequently used in the United States is the Fahrenheit scale, invented in 1714
by German physicist Gabriel Daniel Fahrenheit (1686-1736). On the Fahrenheit scale, the boiling point
of water is 
F, and the freezing point is 
F.
For
more than a decade, scientists have warned that cars and factories spew so many
gases into the atmosphere that Earth could soon be affected by disastrous
climatic changes. The loss of rain
forests is reducing the number of trees to offset the large increases in carbon
dioxide in our atmosphere. The possible
consequences are so frightening that it makes sense to slow the buildup of
carbon dioxide through preventive measures, such as encouraging energy
conservation, developing alternatives to fossil fuels, and preventing the
destruction of the rain forests.
Introduction Task Process Websites Evaluation
You will use mathematics to
analyze aspects of the greenhouse effect and report your findings. As a scientist commissioned to explore the
greenhouse effect, you will conduct two experiments. The first experiment is a control experiment that will be
used to compare data with the second experiment, called the greenhouse
experiment.
Control
Experiment
1.
You will need the greenhouse
spreadsheet to record your findings.
2.
Groups 1 and 2 will set the thermometer 2 inches away from
the overhead. Groups 3 and 4 will set
the thermometer 3 inches away from the overhead. Groups 5 and 6 will set the thermometer 4 inches away from the
overhead. Groups 7 and 8 will set the
thermometer 5 inches away from the overhead.
Groups 9 and 10 will set the thermometer 6 inches away from the
overhead. Make sure the overhead is
turned off.
3.
Measure and record the temperature and the distance
between the thermometer and the overhead.
4.
Place the thermometer on the ruler and tape the
thermometer to the ruler. Place the
ruler on the overhead.
5.
Turn the overhead on and leave it on for five
minutes. Use a stopwatch to keep
accurate time.
6.
Record the new temperature and find the difference of the
temperatures.
Let the thermometer and
overhead cool to room temperature. You
will need to collect the data from the other groups to add the information to
the control experiment sheet.
Greenhouse Experiment
1.
You will need the greenhouse
spreadsheet to record your findings.
2.
Make sure that the thermometer has cooled to room
temperature. Then record the
temperature.
3.
Put the thermometer in a plastic bag and close the
bag. Make sure that the bulb of the
thermometer does not touch the bag.
Then place the thermometer the same distance from the overhead as you
did in the control experiment. Record
the distance between the thermometer and the overhead. Then turn the overhead on and leave it on
for five minutes.
4.
Record the new temperature. Then find the difference of the temperatures.
You
will need to collect the data from the other groups to add the information to
the greenhouse experiment chart
Introduction Task Process Websites Evaluation
Once you have collected the data for the
experiments, you will answer and follow the instructions for the following
questions. You will be analyzing the
data and writing a report to concerned citizens concerning the greenhouse
effect and global warming. There are
websites provided for you to access and explore this topic.
1.
Examine the data from the control experiment. Look for patterns and relationships in the
data. Analyze how the change in
temperature is related to distance.
Describe your analysis in writing.
Be sure to explain any patterns you see in the data.
2.
Examine the data from the greenhouse experiment. Look for patterns and relationships in the
data. Analyze how the change in
temperature is related to the distance.
Describe your analysis in writing.
Be sure to explain any patterns you see in the data.
3.
Compare the two experiments. List the similarities and the differences in the data and explain
the factors that might cause them.
4.
Think about the design of the two experiments. How were they different: Why do you think they were designed the way
they were? How do they relate to the
greenhouse effect?
5.
What would the difference in temperature be between Earth
with carbon dioxide and Earth without carbon dioxide? Do you think life could exist on Earth without carbon dioxide? Explain.
6.
What is the difference in temperature between Mars and
Earth without carbon dioxide? Explain
what other factors contribute to the difference in temperature.
7.
What is the difference in temperature between Venus and
Mars? Explain what other factors
contribute to the difference in temperature.
8.
Make a chart that shows the three planets and their
temperatures with carbon dioxide in their atmospheres and with little or no
carbon dioxide. Assume that the
differences in the temperatures for the other planets would be the same as the
difference in Earth’s temperatures with carbon dioxide and without carbon
dioxide. Use the headings Planet, Temperature Without Carbon Dioxide,
Temperature With Carbon Dioxide, and
Distance From the Sun.
9.
Draw a conclusion about the relationship between the
distance from the sun and temperature of Venus and Earth with carbon dioxide.
10.
Draw a conclusion about the relationship between the
distance from the sun and temperature of Mars and Earth with carbon dioxide.
11.
How does the experiment explore the temperatures of the
planets? How are the relationships
similar and different?
12.
Predict what the temperature of Mars would be if it had
the same amount of carbon dioxide that Earth has. Explain your calculations.
13.
Make a chart that shows the changes in the levels of
carbon dioxide in our atmosphere.
Assume that the levels of carbon dioxide grow at a constant rate over
time (the same amount every year). Use
the headings Year, Amount of Carbon
Dioxide (ppm), and Change. Start the chart with 1920, and end with the
present year.
14.
Write a paragraph about the patterns you see in your
chart.
15.
Based on the relationships you found in the previous
question, determine how much carbon dioxide was in the atmosphere in 1800 and
1950. Explain how you found those
amounts.
16.
Predict the amounts of carbon dioxide that will be in the
atmosphere in the years 2000, 2020, 2050, and 3000. Explain how you made your predictions.
17.
Use the formula, F= 9/5C + 32, to convert the average
temperatures of Mars, Earth, and Venus from Celsius to Fahrenheit. How do the temperatures compare?
18.
The greenhouse effect may raise the average temperature of
Earth 8 F by the year 2050. What will
be the average temperature of Earth in degrees Celsius at that time?
19.
Change the formula for converting Celsius to Fahrenheit to
a formula for converting Fahrenheit to Celsius. (Hint: Solve the formula
in #17 for C).
20.
Some scientists predict that by the year 2050, Earth’s
atmosphere will contain between 500 and 700 ppm of carbon dioxide. Write a one-page paper explaining the
situation to a group of concerned citizens.
Consider some of the following questions to address in your paper.
·
What factors will cause this increase in carbon dioxide?
·
How different is this estimate from the amount of carbon dioxide
calculated earlier?
·
In your opinion, what will the approximate average temperature on
Earth be at that time?
·
What might occur if the temperature reaches that point? What are some of the dangers involved?
Introduction Task Process Websites Evaluation
Websites to locate information
http://seds.lpl.arizona.edu/nineplanets/nineplanets/nineplanets.html
http://www.epa.gov/globalwarming/
http://lwf.ncdc.noaa.gov/oa/climate/globalwarming.html
Introduction Task Process Websites Evaluation
Evaluation
|
|
Beginning 1 |
Developing 2 |
Accomplished 3 |
Exemplary 4 |
Score |
|
Mathematical Computations
|
Mathematical computations are incorrect. |
Mathematical computations are somewhat correct. |
Mathematical computations are mostly correct. |
All mathematical computations are correct. |
|
|
Written explanations
|
Written explanations are not satisfactory. |
Written explanations are satisfactory. |
Written explanations are effective. |
Written explanations are exemplary. |
|
|
Charts and Graphs
|
Charts, graph, and letter are not appropriate and sensible. |
Charts, graph, and letter are. |
Charts, graph, and letter are. |
Charts, graph, and letter are appropriate and sensible. |
|
|
Problem Solving Strategies
|
Does not use appropriate strategies to solve problems. |
Uses some appropriate strategies to solve problems. |
Mostly uses appropriate strategies to solve problems. |
Uses appropriate strategies to solve problems. |
|
|
Concepts |
Shows little or no understanding of the concepts of the greenhouse effect, global warming, data analysis, subtraction of rational numbers, equations, and formulas. |
Shows understanding of most of the concepts of the greenhouse effect, global warming, data analysis, subtraction of rational numbers, equations, and formulas. |
Shows understanding of the concepts of the greenhouse effect, global warming, data analysis, subtraction of rational numbers, equations, and formulas. |
Shows a thorough understanding of the concepts of the greenhouse effect, global warming, data analysis, subtraction of rational numbers, equations, and formulas. |
|
Introduction Task Process Websites Evaluation
Conclusion
I hope that you will
gain some understanding how mathematics can be used every day to analyze
data. Many scientists spend their day analyzing
the temperature on planet Earth and make calculations based on this information
like you did in this project.
Credits & References
Glencoe
Algebra I textbook.