Geology 110: Earth and Space Science
Chapter 17 (Global Change)
Homework
SELF-REFLECTION AND COMPREHENSION SURVEYS
Checkpoint 17.1, p. 490
#1: Which of the following statements is the best analogy?
a) An umbrella is to rain as the stratosphere is to solar radiation.
b) An umbrella is to rain as the stratosphere is to ultraviolet radiation.
c) An umbrella is to rain as the stratospheric ozone is to solar radiation.
d) An umbrella is to rain as the stratospheric ozone is to ultraviolet radiation.
Checkpoint 17.2, p. 491
#2: Which of the following concept maps best represents the sequence of transformations
associated with the formation and destruction of ozone in the stratosphere? Explain the
reasoning behind your choice.
Answer:
Checkpoint 17.3, p. 492
#3: The following graph represents the variation of ozone thickness over 4 cities: Darwin,
Australia, 12º S; Melbourne, Australia, 37º S; San Francisco, U.S.A., 37º N; London,
U.K., 55º N). Explain which city goes with each of the 4 plots. Then sketch an estimated
plot for the city where you live.
46
Checkpoint 17.4, p. 492
#4: Reductions in ozone concentrations involve all aspects of the Earth system. UV
radiation that interacts with ozone comes from the exosphere (the Sun). There is a
potential effect on the biosphere, and the hydrosphere, atmosphere, and geosphere all
have roles to play. Develop a concept map that illustrates the characteristics of ozone and
includes references to different components of the Earth system.
Checkpoint 17.5, p. 493
#5: Examine Figure 17.6. Describe the correlation between the minimum ozone
concentrations and the size of the “hole” in the ozone over Antarctica.
Checkpoint 17.6, p. 493
#6: How would a scientist tell the difference between ozone loss due to chlorine from
CFCs and loss due to chlorine from a volcanic eruption?
Checkpoint 17.7, p. 494
#7: Students in a college Earth science class were asked to concisely describe the
relationship between CFCs and ozone destruction on an exam. Analyze the following 4
47
students’ responses below and rank them from best to worst. Justify your answer choices.
Finally, write your own answer to the question in the space below.
A. CFCs are manufactured gases that destroy the ozone layer and produce oxygen.
B. Chlorine forms from the disintegration of manufactured gases. The chlorine reacts
with ozone molecules to form 2 gases that cannot block incoming UV radiation.
C. Oxygen molecules are broken down by UV radiation to free oxygen atoms that
combine with chlorine monoxide to form new oxygen molecules and free chlorine.
Chlorine helps break down CFCs with UV radiation.
D. UV radiation breaks apart complex manufactured chlorofluorocarbons into its
constituent atoms, including chlorine. Chlorine destroys ozone molecules as it cycles
through a pair of reactions that produce free oxygen molecules.
Response:
Why?
Checkpoint 17.8, p. 494
#8: Given the natural variations in climate that we discussed in the Chapter 16, some
people argue that governments acted too hastily to ban the use of CFCs just 7 years after
the ozone hole had been identified. Summarize 3 arguments for and 3 arguments against
the ban on CFCs.
Checkpoint 17.9, p. 496
#9: What is the difference between the greenhouse effect and global warming?
Checkpoint 17.10, p. 497
#10: Carbon is stored in carbon reservoirs, or sinks, just as water is stored in a reservoir
behind a dam. The carbon is released from these reservoirs and ultimately ends up in
another reservoir. Complete the following table to identify how carbon is stored and
released from each component of the Earth system.
Sink/Source
Carbon is stored when...
48
Carbon is released when...
Atmosphere
Biosphere
Hydrosphere
Geosphere
Checkpoint 17.11, p. 497
#11: Use the concept map provided here to illustrate the natural global carbon cycle by
showing how carbon is transferred among the components of the Earth system.
A CO2 captured in air bubbles in breaking waves
B
C
D
E Carbonate extracted from ocean for shells
F
G
H
I
J
K Plants release CO2 during decay
L
49
Checkpoint 17.12, p. 501
#12: Review the following 3 scenarios described below and discuss the implications for
global greenhouse gas emissions. Then complete the graph provided here to show how
global carbon emissions would change over the century for each scenario. We are more
interested in the trends than the absolute values you identify for each scenario.
Scenario A: Global population peaks around 9 billion in 2050 and declines thereafter.
New technologies are rapidly introduced, and economic disparities between
regions are substantially reduced. Fossil fuels continue to supply most of Earth’s
energy.
Scenario B: Global population continues to increase throughout the twenty-first century
(11 billion by 2050). Disparities in economic growth of regions persist, and
technological change occurs slowly. The energy supply changes from fossil fuels
toward alternative energy sources.
Scenario C: Global population peaks at around 9 billion in 2050 and declines thereafter.
Economies rapidly become service- and information-oriented, income disparities
decrease, and energy technologies that do not rely on fossil fuels are introduced.
(already completed..change?)
Checkpoint 17.13, p. 503
#13: Where would you expect to see the most significant cooling effects due to aerosols?
Explain your answer choice.
a) Near the Poles
c) Between 30-60º N latitudes
b) Around the equator
d) Between 30-60º S latitudes
50
Checkpoint 17.14, p. 503
#14: Explain how Milankovitch cycles can be described in Chapter 16 in terms of a
climate forcing.
Checkpoint 17.15, p. 504
#15: Add labels and arrows to the following diagram to illustrate forcings and feedback
mechanisms for Earth’s climate system. Add elements to the figure as needed.
Checkpoint 17.16, p. 505
#16: Explain why computer climate models are really “Earth system” models.
Checkpoint 17.17, p. 506
#17: Identify 3 things a private citizen could do to reduce the amount of greenhouse gases
produced on his or her behalf.
Checkpoint 17.18, p. 508
#18: Use Figures 17.18, 17.19, 17.20, and the Venn diagram provided here to compare
the predicted climate changes in North America with those in South America by 2100.
Identify at least 12 items.
51
North America
South
America
1. Greatest temperatures rise in northern sections of continents
2.
3.
4.
5. Greatest temperature increase in presently warmest locations
6.
7.
8.
9.
10.
11.
12. Sea level increases more along west coasts
Checkpoint 17.19, p. 508
#19: During a homework assignment, some students provide the following descriptions
of global warming. Review the definitions and rank them in order of accuracy. (1 = most
accurate; 5 = least accurate). Describe the criteria you used to rank the definitions. (For
example, why are definitions you rank 1 and 2 better than those you rank 3 and 4?)
__Global warming is the gradual warming of Earth due to the greenhouse effect.
__Global warming is a gradual, long-term increase in the temperature of Earth due to an
increase in the concentration of trace atmospheric gases such as carbon dioxide that
absorb heat from Earth’s surface.
__Global warming occurs when the temperature of the Earth slowly increases because a
layer of chemicals in the atmosphere absorbs more heat than normal.
__Global warming is the result of the ozone layer in the atmosphere becoming thinner
due to certain chemicals we use. This causes more solar radiation to reach Earth’s
surface, leading to higher average temperatures.
__Global warming is the warming of climate over many years as a result of natural
phenomena, such as volcanic eruptions, that trap heat close to Earth’s surface.
52
Criteria used?:
Checkpoint 17.20, p. 508
#20: In this section, we discussed 6 possible effects of warmer temperatures on nations
and people. Consider the climate where you live. Write 1 sentence explaining specifically
how each of the possible effects may impact people living there 100 years from now.
Place your sentences in order from the most negative impact to least negative (or
positive) impact.
Checkpoint 17.21, p. 509
#21: Suppose the Kyoto Protocol had been adopted and successfully implemented by the
entire global community starting in 1998. Explain how those changes might have
impacted the CO2 data displayed in Figure 17.10.
Checkpoint 17.22, p. 510
#22: Does cutting your grass and trimming your trees ultimately add carbon, reduce
carbon, or have no impact on carbon in the atmosphere and why (or why not)?
Checkpoint 17.23, p. 510
#23: Explain how the comment “Earth can take care of itself” in the context of global
warming relates to the concept of “deep time” discussed in Chapter 8, “geologic time.”
Checkpoint 17.24, p. 510
#24: What are some of the potential actions that could be taken to diminish the impact of
global warming? Different groups of people have different perspectives on this issue. For
some, solutions that would avert global warming may not be in their best interest.
1. List actions each of the following interest groups could take to reduce global warming.
i.
A major oil company
ii. A utility that burns coal to generate electricity
iii. A large car manufacturing company
iv. A company that manufactures wind turbines and solar energy panels
v. An international insurance company
vi. The Maldives, a small island nation with an average elevation of ~1 meter
53
vii. A heavily populated developing nation (e.g., China, India)
viii. A heavily populated developed nation with a high standard of living (e.g., United
States)
ix. A family of four in the United States with two vehicles.
Some interest groups are essentially powerless to do anything themselves and must rely
on the actions of others. Consider the first 2 questions below and evaluate the answer for
each group.
2. What would be the impact of global warming on each group?
3. How does the activity of each group impact future global warming?
Choose any 3 of the groups and answer these 2 questions for each group you choose.
4. If applicable, what steps could the group take to diminish the group’s impact on global
warming?
5. What incentives would encourage the group to change its habits to reduce its
contribution to future warming?
Global Change Concept Map
#25: Complete the following concept map to evaluate your understanding of the
interactions among the Earth system and global change. Label as many interactions as
you can, using information from this chapter.
A
B
C
D
E
F
G
H
I
Solar radiation warms Earth
Cold Antarctica cools overlying atmosphere; volcanic eruptions produce chlorine
54
J
K
L
Power companies release greenhouse gases from burning coal; Du Pont
manufactured CFCs
55