502 Lesson 4

LESS

ON 4 Responding to Climate Change

TODAY MOST PEOPLE AGREE that climate change is occurring, and that we need to do something about it. How do we meet this chal-lenge? There are specific things that people and nations can do to address global warming.

Use and Production of Electricity Ways of reducing the production of greenhouse gases include

conserving electricity and finding new ways to produce electricity.

We can respond to climate change in two basic ways—adaptation and mitigation. One approach, adaptation, involves protecting people from the effects of global warming. For example, residents of the Maldives have built a sea wall around the nation’s capital to protect roads and buildings from storms.

FIGURE 16 An Adaptation Strategy A sea wall is being constructed to protect seaside property from rising sea levels in Sydney, Australia.

• List ways to reduce greenhouse gases related to the use and generation of electricity.

• Describe some of the ways of reducing greenhouse gases related to transportation.

• Describe other strategies for reducing greenhouse gases.

• Explain how nations are working together to try to address climate change.

Reading Strategy How can you save electricity in your home? Write down what you know. Then, as you read the lesson, write additional ways that you and your family can conserve electricity.

Vocabulary carbon footprint, carbon tax, carbon offset, carbon sequestration, Kyoto Protocol

Guiding Question: How can we respond to climate change?

FOCUS Make a three-column table on the board. Label the columns Individuals, Corporations, and Governments, respectively. Give stu-dents several moments to discuss how these groups might respond to climate change. Record students’ re-sponses in the table. Have them add to the table as they read the lesson.

GUIDING QUESTION

16.4 LESSON PLAN PREVIEWInquiry Students research local electricity generation. Real World Students explore ways to reduce the consump-tion of fossil fuels for transpora-tion.Differentiated Instruction Advanced students form a supported opinion about the Kyoto Protocol.

16.4 RESOURCESLesson 16.4 Worksheets • Lesson 16.4 Assessment • Chapter 16 Overview Presentation

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Mitigation consists of reducing greenhouse gas emissions. By doing this, we will lessen the severity of future climate change. Mitigation includes strategies such as improving energy efficiency and preventing deforestation. We need to pursue both adaptation and mitigation. How-ever, in the long term, mitigation is more important because it addresses the causes of global warming. Each of us should be trying to reduce our carbon footprints. A carbon footprint is the amount of carbon dioxide emissions for which an individual or group is responsible.

A major mitigation strategy addresses how we use and produce electricity. Electricity generation is the largest source of U.S. greenhouse gases. Fossil fuel combustion generates about 70 percent of the electric-ity in the United States. There are ways to reduce the amount of green-house gases released during the generation of electricity. First, we need to encourage energy efficiency and conservation. In addition, we need to switch to energy sources that are cleaner and renewable.

Efficiency and Conservation Efficiency consists of using energy effectively—that is, accomplishing a job using as little energy as possible. Conservation consists of reducing energy use.

▶ Efficiency New technologies, such as high-efficiency light bulbs and appliances, provide more effective ways to use electricity. The U.S. Environmental Protection Agency (EPA) offers technological solutions through its Energy Star Program. This program rates household appliances, lights, windows, fans, office equipment, and heating and cooling systems by their energy efficiency. For instance, ratings indicate that by replacing stan-dard light bulbs with compact fluorescent bulbs, you can reduce energy use for lighting by about 75 percent. In addition, certain kinds of appliances, such as air conditioners and refrigerators, must have an EnergyGuide label similar to the one shown in Figure 17. EnergyGuide labels give consumers information about the energy efficiency of these appliances.

▶ Conservation In addition, individual people can make lifestyle choices that reduce the use of electrical appliances and other devices. Here are just a few things that you and other people can do:•  Turn off lights, computers, and televisions when not in use.•  Wash only full loads in dishwashers and clothes washers.•  Unplug appliances that you seldom use, such as food processors.•  Unplug cell-phone chargers once the phone is charged.•  Don’t keep the refrigerator door open. Remove food quickly.•  Use a microwave oven, rather than a conventional oven, to heat food.

ReadingCheckpoint

What is the largest source of U.S. greenhouse gases?

Alternate Sources of Electricity Energy sources that produce electricity without using fossil fuels are another way to reduce greenhouse gases. For example, nuclear power comes from reactions that take place within atoms. Solar power uses energy from the sun. Wind power depends on wind to make electricity, and hydroelectric power uses the movement of water. Geothermal power makes use of heat trapped underground. These energy sources do not give off greenhouse gases.

FIGURE 17 EnergyGuide An EnergyGuide label gives consumers an estimate of how much it costs to run an appliance for a year. If the label has the Energy Star logo, the appliance uses less energy than typical models of the appliance.

ANSWERS

Reading Checkpoint The genera-tion of electricity

100%Gas14%Movingcar

62%Engine heatloss, friction,ine�ciencies

17%Idling

5%Drive train

friction andine�ciencies

2%Running

accessories:water pump,stereo, etc.

Make A Difference

Make A Difference

504 Lesson 4

Transportation By choosing more efficient cars, driving less, and using public

transportation, people can reduce greenhouse gas emissions.

Transportation is the second largest source of U.S. greenhouse gas emis-sions. The average American family makes 10 trips by car each day. Unfortunately, the typical automobile is not very efficient. More than 85 percent of the fuel does something other than move the car down the road, as shown in Figure 18. Automobiles powered by gasoline may always remain somewhat inefficient. However, there are steps we can take to reduce the release of greenhouse gases produced by transportation.

Vehicle Technology The technology exists to make cars and trucks more fuel-efficient than they are now. Vehicles in the United States are generally not as fuel-efficient as they are in many other nations. It will probably take both government regulation and consumer demand to improve fuel efficiency in the United States. As gasoline prices rise, people will demand more fuel-efficient cars.

There are now alternatives to cars that burn only gasoline. For example, hybrid vehicles combine electric motors and gasoline-powered engines. Researchers are investigating alternative fuels such as com-pressed natural gas. In addition, scientists are working on developing motor vehicles with hydrogen fuel cells that use oxygen and hydrogen. These fuel cells produce only water as a waste product.

Driving Less and Using Public Transportation People can reduce their dependence on cars. For example, some people are choosing to live closer to their workplaces or to work from home. In addition, students can bike or walk to school or to complete their everyday activities.

Still other people use mass transportation, such as buses and subways. According to one study, increasing our use of public transportation may be the most effective strategy for saving energy and reducing pollution. Public transportation in the United States already reduces gasoline use. If people use public transportation more, the United States could signifi-cantly reduce its contribution to climate change. Unfortunately, many communities lack good public transportation.

FIGURE 18 Energy Loss in a Car Most cars are inefficient. Notice that, in a typical car, only 14 percent of the energy from fuel is used to move the car.

You and your family may be needlessly spending $100 a year if you keep electronic devices, such as computers and CD players, plugged in all the time. As long as they’re plugged in, electronic devices use a little bit of electric-ity, even when they haven’t been turned on. So unplug that com-puter or TV!

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Other Approaches to Reducing Greenhouse Gases

Greenhouse gas emissions can also be reduced through improved agriculture and forestry, cap-and-trade policies, carbon taxes, carbon offsets, and carbon sequestration.

In addressing global climate change, it is important to improve efficiency and conservation in generating electricity and using motor vehicles. But governments, industries, scientists, and individual citizens are also exploring other strategies to reduce greenhouse gas emissions.

Agriculture and Forestry Soil and forests absorb carbon dioxide. Careful farming practices, such as the prevention of erosion, help pre-serve soil’s ability to hold carbon. In addition, agricultural scientists have developed techniques to reduce the greenhouse gases that come from sources such as rice cultivation, livestock, and manure. In forestry, new trees planted to replace those that have been cut down (Figure 19) take in carbon dioxide and help prevent soil erosion.

Cap-and-Trade Some industries are better than others in reduc-ing greenhouse gas emissions. In a cap-and-trade program, a govern-ment puts a limit (cap) on the amount of greenhouse gases that can be released by specific industries and power plants. Industries that release less greenhouse gas than they are allowed can sell their leftover allow-ances to industries that are less efficient. Suppose, for example, a factory is allowed to release 100 units of carbon dioxide. However, it only releases 75 units. The factory can sell the leftover 25 units to a factory that is having difficulty reducing its emissions as much as is required. Cap-and-trade programs work well only if the caps are progres-sively lowered.

Carbon Tax Many scientists and policy makers think that cap-and-trade programs are ineffective. A carbon tax is an alternative. A carbon tax is a fee that a government charges polluters for each unit of greenhouse gases they emit. This gives polluters a financial incentive to reduce their emissions. Several European nations have established carbon taxes. However, the downside of a carbon tax is that most pol-luters simply pass the cost along to con-sumers by charging higher prices for the goods and services they sell.

ReadingCheckpoint

How does preventing ero-sion help limit greenhouse gas emissions?

FIGURE 19 Replacing Lost Trees Trees take in carbon dioxide, so replacing lost trees prevents some carbon dioxide from entering the atmosphere.

ANSWERS

Reading Checkpoint Soil absorbs carbon dioxide. Preventing erosion, therefore, limits greenhouse gas emissions.

506 Lesson 4

Carbon Offsets A carbon offset is a voluntary payment made when one industry or person, instead of reducing its own greenhouse gas emissions, pays another group or person to do so. Suppose, for example, a person is taking an airplane trip. The airplane passenger finds out how much greenhouse gas the plane will release during the trip and determines one passenger’s share of the total emissions. The passenger might pay a carbon-offset organization to plant trees that will take in enough carbon dioxide to compensate for those emissions.

Carbon offsets may seem like a great idea, but in practice it is often difficult to establish effective systems of exchange. At present, there are more potential buyers of carbon offsets than there are sellers. In addition, the offset may not accomplish what it is intended to do. Efforts are being made to create a reliable offset process. If these efforts succeed, then car-bon offsets could become an important way to deal with climate change.

Carbon Sequestration Scientists are investigating ways to remove carbon dioxide from power plant emissions. Carbon sequestration, or storage, consists of ways of storing this captured carbon. For example, the carbon might be stored underground. However, there is no guarantee that the carbon will not leak out. And some experts doubt that we will ever be able to capture and store enough carbon to make much difference in over-all release of carbon dioxide.

Cooperation Among Nations The Kyoto Protocol is an agreement among many nations to

reduce greenhouse gas emissions.

In 1992, many nations signed the United Nations Framework Convention on Climate Change (UNFCCC). This framework was a voluntary plan for reducing greenhouse gas emissions. By the late 1990s, however, it was clear that a voluntary approach was not likely to succeed. After watching the seas rise, developing nations, including the Maldives, helped begin an effort to create an international treaty to address the problem. This effort led to the Kyoto Protocol.

FIGURE 20 Carbon Offsets Airplane passengers can sometimes buy carbon offsets to compensate for their share of the greenhouse gases released by the airplane.

ANSWERS

Lesson 4 Assessment

1. Answers will vary, but should be well supported.

2. Sample answer: High gasoline prices; technology that makes smaller, fuel-efficient vehicles less expensive than larger vehicles

3. Sample answer: Our family might use a carbon offset to compensate for the greenhouse gas emis-sions released when we travel by airplane.

4. Sample answer: A major limitation of the Kyoto Protocol is that devel-oping nations are not required to reduce emissions.

5. Accept all reasonable answers. Some students may propose a treaty that limits allowable green-house gas emissions, rewards the development of technologies that limit greenhouse gas emissions, and contains penalties, such as fines, for noncompliance. Students may oppose any provision that weakens the treaty.

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41. Form an Opinion Which is more important in

addressing global climate change: conserving elec-tricity or finding new ways of producing it? Explain your answer.

2. Infer What factors are likely to make consumers in the United States prefer small, fuel-efficient cars to large vehicles?

3. Explain Describe an example of how you or your family might use a carbon offset.

4. Form an Opinion What is a major limitation of the Kyoto Protocol?

5. Explore the BIGQUESTION You have been appointed as the United States representative to an international conference that will replace the Kyoto Protocol. All nations recognize that the Kyoto Protocol was not fully effective, and most are committed to creating a stronger agreement. What type of agreement will you try to shape? Describe at least three components you would support and at least one you would oppose.

The Kyoto Protocol The Kyoto Protocol is an international agreement that seeks to limit green-house gas emissions. Unlike the UNFCCC, the Kyoto Protocol is binding, not voluntary. Nations that signed the treaty committed to reducing emis-sions of greenhouse gases to levels below those of 1990. The treaty took effect in 2005 after Russia became the 127th nation to ratify it.

The United States did not sign the Kyoto Pro-tocol. Some U.S. leaders called the treaty unfair because the Kyoto Protocol required developed nations to reduce emissions but did not require the same of developing nations, such as China and India. Supporters of the Kyoto Protocol said the different requirements were justified because industrialized nations created the current greenhouse gas problem. There-fore, developed nations, including the United States, should take the lead in solving it.

Looking Ahead Nations are now looking ahead to plan what will fol-low the Kyoto treaty. In December 2009, delegates from 192 nations met in Copenhagen, Denmark, to try to develop an international agreement to address climate change. However, no agreement had been reached by the last day of the conference. Then, leaders of several nations, includ-ing the United States, put together a last-minute agreement, called the Copenhagen Accord, that fell far short of most nations’ hopes. In the Copenhagen Accord, developed nations offered to pay billions of dollars to developing nations to help fund mitigation and adaptation strategies. Developed nations also agreed to set specific targets for emission reduc-tion by 2020.

The Copenhagen Accord was nonbinding. However, nations agreed to meet in the future to develop a binding agreement. More and more scientists and policymakers are saying that immediate action on climate change is necessary. Reducing greenhouse gases is one of the foremost challenges for the world.

FIGURE 21 Underwater Meeting On October 17, 2009, government officials in the Maldives held an underwater meeting. Infer The meeting took place shortly before the Copenhagen conference began. What message were the Maldives officials sending to the conference delegates?

ANSWERS

Figure 21 The likelihood that the Maldives will be underwater un-less greenhouse gas emissions are reduced