Chapter 20: Climate change
From 400,000 to 50,000 years ago, the carbon dioxide levels fluctuated between ___________.
180 and 280 ppm Submit
How much of the Sun's incoming radiation is scattered or reflected back to space before any heating effect is felt on Earth?
31%
The Vostok ice core curve shows CO2 concentrations over the last __________.
400,000 years
How much of the Sun's incoming radiation is absorbed by Earth's surface?
45%
Today, it takes about ______ Calories of energy to produce about 1 Calorie of food.
55
What has analysis of ice cores revealed about atmospheric greenhouse gas levels during the historic period?
A sudden rise in greenhouse gas levels coincides with the start of the Industrial Revolution. Submit
When looking at Earth's most at-risk land, what general pattern emerges?
Areas north and south of the Sahara Desert are very vulnerable to land degradation.
What would happen to Earth's atmospheric temperature if the amount of shortwave radiation reflected at Earth's surface increased significantly?
Atmospheric temperature would decrease.
What would happen to Earth's atmospheric temperature if the amount of incoming shortwave radiation from the Sun decreased and was less than the longwave radiation lost to space?
Atmospheric temperature would decrease. Submit
What would happen to Earth's atmospheric temperature if the amount of outgoing longwave radiation decreased so that it was less than incoming shortwave radiation from the Sun?
Atmospheric temperature would increase.
What would happen to Earth's atmospheric temperature if the amount of shortwave radiation reflected by clouds decreased significantly?
Atmospheric temperature would increase.
What would happen to Earth's atmospheric temperature if the amount of incoming shortwave radiation from the Sun was the same as the longwave radiation lost to space?
Atmospheric temperature would remain the same.
What is the primary cause of the nearly 20 percent increase in atmospheric carbon dioxide levels since the 1960s?
Burning of fossil fuels
The two main locations where ice cores are drilled are the Antarctic and __________ Ice Sheets.
Greenland
During peak usage, what happens to the cost of electricity?
It almost always increases.
What evidence is there that the O'Higgins Glacier is being affected by global warming?
It has retreated nine miles in the past 100 years because of melting. Submit
What happens to the energy that the ground absorbs in the form of visible sunlight?
It is returned upward in the form of infrared light.
On a cloudless day, what happens to most of the visible light headed toward Earth?
It reaches Earth's surface, where some is reflected and some is absorbed. Submit
How do the oceans contribute to maintaining a climate that is habitable for humans?
Oceans absorb large quantities of carbon dioxide from the atmosphere.
When does Cognito Farm use antibiotics on its cattle?
Only when they are sick.
Which of the following best describes the energy conversion sequence in the solar panel system described in the video?
Photons carrying energy from the sun chemically react with silicon crystals to generate a flow of electrons.
What is causing a decline in Antarctica's Chinstrap penguins?
Populations of the penguin's major food source are declining because of melting sea ice.
What impact will increased carbon dioxide absorption by the oceans have on coral reefs?
Reefs will degrade over time, ultimately resulting in large-scale mortality.
What impact would rising sea levels have on human migration?
Rising sea levels would cause enormous migration as people move inland away from affected areas.
How did the University of Florida help address the problem of global warming?
The athletic program reduced local energy consumption and planted trees.
If the greenhouse effect ceased to exist on Earth, which of the following would result?
The average surface temperature would drop to below the freezing temperature of water.
On a day with complete cloud cover, what happens to the visible light headed toward Earth?
The clouds reflect some of it back to space, and some still reaches the surface.
Which of the following is true about Venus?
The high abundance of greenhouse gases absorb most outgoing longwave radiation.
How will increases in atmospheric carbon dioxide levels affect oceans?
The oceans will become more acidic.
What would happen to the oxygen atoms in ozone if the ozone layer were completely destroyed by ultraviolet radiation?
The oxygen atoms would be bound together in pairs.
How does planting trees offset carbon generated by the University of Florida athletic program?
The planted trees will sequester carbon dioxide from the air as they grow.
Which of the following would indicate that a home is using solar power to generate electricity and is NOT using batteries?
There are solar panels on the roof and power lines going to the home.
Which of the following is true when comparing the Amundsen-Scott South Pole station and Barrow, Alaska CO2 concentration curves?
They show opposite seasonal curves.
Why are scientists doing research in an underwater lab in the Great Barrier Reef?
To replicate future carbon dioxide levels and measure the changes in coral reef productivity, mortality and health
How is ozone formed in the stratosphere?
Ultraviolet radiation breaks apart molecules made up of paired oxygen atoms. Individual oxygen atoms bond with paired oxygen molecules to form ozone.
How does ultraviolet radiation cause ozone depletion?
Ultraviolet radiation breaks down CFC, a molecule containing chlorine. Chlorine then breaks one oxygen atom away from ozone, leaving behind a paired oxygen molecule.
In the climate system diagram, modeling results show that observed changes in temperature closely align with __________.
a combination of both natural and human effects
What is ozone?
a molecule made up of three oxygen atoms
The Moon has __________ because all energy is reradiated back to space.
a relatively low average surface temperature
What color smoke coming from a coal-fired power plant would indicate wasted fuel?
black
Cognito Farm avoids washing chicken carcasses with __________, which is done at many packing plants in the United States.
bleach
Many pollutants from coal-fired power plants are properly managed today. Which of the following is currently considered to be the biggest threat to the environment?
carbon dioxide
What is used at Cognito Farm to control fly larvae in the pasture?
chickens
The Neutral Gator program used methods that _____.
decreased production of carbon dioxide and reduced the amount of carbon dioxide already in the atmosphere
Fans attending University of Florida athletic events are responsible for providing carbon offsets for _____.
fossil fuels used to get fans to and from the stadium
Where is electricity made at a coal-fired power plant?
generator
The greenhouse effect raises Earth's surface temperature (from what it would be otherwise) because the infrared light radiated by Earth's surface __________.
is temporarily absorbed by greenhouse gases and then reemitted in random directions Submit
The dense atmosphere of Venus is ________, causing most incoming solar radiation to be _________.
light in color; reflected
How much of the Sun's ultraviolet radiation reaches Earth's surface?
little of the ultraviolet radiation Submit
The temperature range of the past 7,000 years was __________ the temperature range of the preceding 30,000 years.
more stable than
The University of Florida's athletic program became carbon neutral because it _____.
promoted programs that reduced fossil fuel use and sequestered carbon
Only some shortwave radiation from the Sun reaches Earth's surface. What is the leading cause of this radiation loss?
reflection by clouds Submit
If a home uses a large supply of solar panels to generate electricity, but has no battery system, surplus electricity that is produced is usually __________.
released into the power grid for others to use, generating a credit to the homeowner
The Sun emits __________ radiation, but it is radiated back off of planetary bodies as __________ radiation.
shortwave; longwave
All fossil fuels, including coal, are considered an indirect form of ____________ energy.
solar
Which of the following is a challenge to using solar-generated electricity in places not connected to a power grid?
the lack of efficient and inexpensive battery technology
The most recent spike of CO2 (over 280 ppm) in the atmosphere correlates to __________.
the onset of the Industrial Revolution
In addition to glacial ice, what other natural climate recorder is discussed in the SmartFigure?
tree rings
Select the statements that correctly describe global environmental change.
-Human activities are likely largely responsible for many of the changes that Earth is currently experiencing at the planetary scale. -Global environmental change refers to changes in any of Earth's systems, not just climate.
Which of the following are ways in which the climate system is affected by the biosphere?
-Trees take up carbon dioxide from the environment and release oxygen. -Methane, a greenhouse gas, is released from the digestive system of cattle. Submit
In a conversation with a friend, he expresses skepticism about global warning. When you inquire about his reasons, he responds by saying that the weather in that area has been the coolest he can remember. Using the information you have learned, what information could you offer to encourage your friend to reevaluate his position?
-Weather and climate are different. Cooler weather does not mean the global climate is also cooler. -"Global warming" means that the average global temperature is increasing. It doesn't mean that temperatures everywhere are hotter.
Your roommate, who has not studied climate, says, "I thought the greenhouse effect was a bad thing. Isn't it what's causing global warming?" Which of the following statements might you use to help your roommate understand the true nature of the greenhouse effect?
-When there are more greenhouse gases in the atmosphere, the greenhouse effect is stronger. -Some gases, like carbon dioxide and water vapor, "trap" the heat radiated by Earth, causing warming.
How is energy transferred from Earth's surface to Earth's atmosphere?
-through latent heat in water vapor -through the greenhouse effect -through convection -through conduction
Figure B1, below, illustrates the interconnectedness between environmental changes currently occurring and with human health.
1) The incidence of skin cancer has increased dramatically in parts of Australia where people are experiencing greater UV exposure as a result of [stratospheric ozone depletion]. 2) As the overall average temperature of Earth rises, changes in weather patterns can challenge human occupations (e.g., farming) and human health (e.g., insect-borne diseases). The term [climate change] describes this overall increase in temperature, as well as the effects of this increase. 3) In the Sahel region, south of the Sahara Desert in Africa, many nomads are losing their livelihoods and agricultural regions. The land has become essentially barren as a result of [desertification/land degradation]. 4) The cost and supply of produce from the drier western United States has fluctuated because of decline in water quantity resulting from [freshwater decline]. 5) Because of rising ocean temperature, the Great Barrier Reef off the coast of Australia is experiencing coral bleaching, which kills resources such as plants and fish populations. This ultimately leads to tremendous [biodiversity loss].
What two trends are commonly seen in modern monthly CO2 concentration charts?
1) an up-and-down seasonal trend, and 2) overall increasing CO2 levels through time
Complete the following sentences, to explore the factors that influence global climate change.
1. Although their concentration in the atmosphere is lower than carbon dioxide, [trace gases] absorb Earth's outgoing radiation and cause warming of the troposphere. 2. When a component of the climate system is altered, the possible responses are known as [climate] feedback mechanisms. 3. Effects that reinforce the initial climate system change are called [positive]-feedback mechanisms. 4. Because they reflect sunlight back into space, [aerosols] have a net cooling effect on the climate system. 5. Effects that produce the opposite results from the initial climate change are referred to as [negative]- feedback mechanisms.
Match the names of the five principal climate groups in the Köppen classification to their descriptions.
1. In a [humid tropical] climate, there is no winter, and the average temperature each month is above 18°C (64°F). 2. The [dry] climate is characterized by a constant deficiency of water because more moisture is lost to evaporation than is gained through precipitation. 3. A coldest month with a temperature below 18°C (64°F) but above -3°C (27°F) is characteristic of a [humid middle-latitude (mild winter)] climate. 4. To be considered a [humid middle-latitude (severe winter)] climate, the coldest month would have an average temperature below -3°C (27°F) and above 10°C (50°F) in the warmest month. 5. In [polar] climates, the warmest month has a mean temperature at or below 10°C (50°F).
On average, how far do agricultural products travel from farm to plate in the United States?
1400 miles Submit
It has been estimated that confined animal feeding operations contribute to about _____ of world carbon dioxide emissions.
15%
The following labels describe six interactions that occur within Earth's climate system. The accompanying figure shows and lists in the boxes different components interacting within Earth's climate system. Match each label with its corresponding change or interaction.
Change in amount of ice-covered land= Glacier melt as temps. increase Changes in amount and type of cloud cover= Rising warm air causes water to condense Changes in atmospheric composition= A volcanic eruption releases gas into the atmosphere Changes in solar imputs= Seasonal variations change the angle of the sunlight reaching Earth's surface Human influences= Slash and burn techniques are used to create new agricultural fields Ocean-agricultural interaction= Warm, tropical oceans add warmth and moisture to the overlying atmosphere.
How might global warming affect cities that rely on glacial runoff for their water supply?
Cities may face long-term water shortages as the amount of water generated by glacial melt will decline as glaciers shrink.
In the solar panel system presented in the video, which of the following was necessary to generate usable electrical current for a home?
DC power had to be converted to AC.
Determine whether the following examples are either nature- or human-induced causes of global environmental change.
naturally-induced global change: -The Hawaiian Islands sit on the Pacific Plate, which is gradually moving in a northeast direction. The Islands formed as the plate moved over a 'hot-spot' on Earth, resulting in volcanic activity that created new land that became Hawaii. Therefore, each island further north in the chain is progressively older, and the newest and largest island is the Big Island, which currently is an active volcano. -In 1883, the Krakatau volcano in Indonesia erupted and emitted so much ash that sunlight could not reach Earth's surface, resulting in much colder winters for the four years following the eruption. -An earthquake strikes in the western Pacific Ocean, which triggers a strong tsunami that hits the coast of Japan a few hours after the earthquake. The tsunami uproots trees, destroys villages, and floods buildings and ecosystems. human-induced global change: -In Brazil, large swaths of the Amazon rainforest have been cut down in order to plant soybean farms. This has resulted in decreased biodiversity in the region due to loss of forest habitat, as well as increased global carbon emissions since carbon is released from the soil when forests are removed. -Globally, cities are expanding into surrounding ecosystems that were vegetated prior to becoming urban. This has created "urban heat islands," where cities are warmer than surrounding vegetated areas due to the fact that impervious surfaces absorb and retain more heat than the natural surfaces they replace. -Due to dams along the Colorado River, the river delta in Mexico on the Sea of Cortez is now dry. When water stopped flowing into the delta, habitats dried up and wildlife, such as coyotes and rattlesnakes, disappeared.
What is another name for the ozone layer?
ozonosphere
CO2 levels drop during spring and summer months because __________.
photosynthetic organisms are absorbing CO2
