reducing air pollution

reducing air pollution from fossil fuels

There are two basic types of strategies for reducing pollution from fossil fuels: 1. Use less fossil fuel to begin with. 2. When fossil fuels must be used, prevent the pollution from entering the air.

using less fossil fuel

We can reduce our use of fossil fuels in several ways: Conserve fossil fuels. For example, turning out lights when we arent using them saves electricity. Why does this help? A lot of the electricity we use comes from coal-burning power plants. Use fossil fuels more efficiently. For example, driving a fuel-efficient car lets you go farther on each gallon of gas. This can add up to a big savings in fossil fuel use. Change to alternative energy sources that produce little or no air pollution. For example, hybrid cars run on electricity that would be wasted during braking. These cars use gas only as a backup fuel. As a result, they produce just 10 percent of the air pollution produced by cars that run only on gas. Cars that run on hydrogen and produce no pollution at all have also been developed (see Figure 22.14).

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preventing ozone loss and global warming

The problems of ozone loss and global warming were unknown in 1970. When they were discovered, worldwide efforts were made to reduce CFCs and carbon dioxide emissions.

keeping pollutants out of the air

Some of the pollutants from fossil fuels can be filtered out of exhaust before it is released into the air. Other pollutants can be changed to harmless compounds before they are released. Two widely used technologies are scrubbers and catalytic converters. Scrubbers are used in factories and power plants. They remove particulates and waste gases from exhaust before it is released to the air. You can see how a scrubber works in Figure 22.15. Catalytic converters are used on motor vehicles. They break down pollutants in exhaust to non-toxic com- pounds. For example, they change nitrogen oxides to harmless nitrogen and oxygen gasses.

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controlling global warming

The Kyoto Protocol is another worldwide agreement on air pollution. It was passed in 1997. The Protocol focuses on controlling greenhouse gas emissions. Its aim is to control global warming. Carbon dioxide is the main greenhouse gas causing global warming. There are several possible ways to reduce carbon dioxide emissions. They include cap-and-trade systems, carbon taxes, and carbon sequestration In a cap-and-trade system, each nation is given a cap, or upper limit, on carbon dioxide emissions. If a nation needs to go over its cap, it can trade with another nation that is below its cap. Figure 22.16 shows how this works. Carbon taxes are taxes placed on gasoline and other products that produce carbon dioxide. The taxes encourage people to use less fossil fuel, which reduces carbon dioxide emissions. Carbon sequestration is any way of removing carbon dioxide from the atmosphere and storing it in another form. Carbon is sequestered naturally by forests. Trees take in carbon dioxide for photosynthesis. Artificial methods of sequestering carbon underground are being researched. The Kyoto Protocol has not been as successful as the Montreal Protocol. One reason is that the worlds biggest producer of greenhouse gases, the U.S., did not sign the Kyoto Protocol. Of the nations that signed it, few are

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protecting the ozone layer

The Montreal Protocol is a worldwide agreement on air pollution. It focuses on CFCs. It was signed by many countries in 1987. It controls almost 100 chemicals that can damage the ozone layer. Its aim is to return the ozone layer to its normal state. The Montreal Protocol has been effective in controlling CFCs. By 1995, few CFCs were still being used. But the ozone hole kept growing for several years after that because of the CFCs already in the atmosphere. It peaked in 2006. Since then, it has been somewhat smaller.

instructional diagrams

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questions

Pollutants regulated by the Clean Air Act include

a. CFCs.

b. carbon dioxide.

-->  c. carbon monoxide.

d. all of the above

A carbon tax

a. encourages people to reduce carbon emissions

b. encourages conservation

c. charges money for carbon emissions

-->  d. all of the above

Air pollutants that destroy ozone high in the atmosphere are regulated by the

a. Clean Air Act.

b. Kyoto Protocol.

-->  c. Montreal Protocol.

d. none of the above

A car that runs on gasoline and electric power is

a. a combustible engine vehicle

-->  b. a hybrid vehicle

c. an electric vehicle

d. a diesel vehicle

In a cap-and-trade system, each nation is given a cap on emissions of

a. CFCs.

-->  b. carbon dioxide.

c. nitrogen oxides.

d. all air pollutants.

Catalytic converters

-->  a. break pollutants into non-toxic compounds

b. only work for particulates

c. reduce pollutants to zero

d. all of these

Removing carbon from the atmosphere is known as

-->  a. carbon sequestration

b. carbon stealing

c. unpolluting

d. carbon burying

Carbon taxes are meant to

a. encourage people to use less fossil fuel.

b. reduce carbon dioxide emissions.

c. control greenhouse gases.

-->  d. all of the above

Ways of reducing air pollution include

a. changing pollutants in exhaust to harmless gases.

b. removing pollutants from exhaust before it is released.

c. using fossil fuels more efficiently.

-->  d. all of the above

Nations benefit from developing emission reducing technologies in

a. trade-and-spend

b. spend-and-reduce

-->  c. cap-and-trade

d. cap-and-reduce

One purpose of catalytic converters is to

a. reduce the use of fossil fuels.

b. remove particulates from exhaust.

-->  c. break down pollutants to safe compounds.

d. convert gas-burning cars to hybrid vehicles.

Scrubbers are used in

a. motor vehicles.

b. power plants.

c. factories.

-->  d. two of the above

Since the passage of the Clean Air Act, emissions of the six major pollutants have decreased by 50%.

-->  a. true

b. false

Removing particles from emissions is a difficult process.

-->  a. true

b. false

Destruction by ozone creates the ozone hole.

a. true

-->  b. false

Efforts to reduce greenhouse gas emissions have been successful.

a. true

-->  b. false

Without the Montreal Protocol, skin cancer cases in the U.S. would have been higher.

-->  a. true

b. false

The Clean Air Act was passed in order to reduce global warming.

a. true

-->  b. false

Because of the Clean Air Act, air pollution has been eliminated completely.

a. true

-->  b. false

Pollution by ozone was reduced at least 50 percent by the Montreal Protocol.

a. true

-->  b. false

Hydrogen cars produce about 10 percent of the air pollution of gas-burning cars.

a. true

-->  b. false

Some scrubbers use steam to remove pollutants from exhaust.

-->  a. true

b. false

The Kyoto Protocol has been more successful than the Montreal Protocol.

a. true

-->  b. false

The size of the hole in the ozone layer has gotten somewhat smaller since 2006.

-->  a. true

b. false

Cap-and-trade systems were developed to reduce the use of CFCs.

a. true

-->  b. false

Carbon is sequestered naturally by forests.

-->  a. true

b. false

The worlds greatest producer of greenhouse gases is the U.S.

-->  a. true

b. false

worldwide agreement on air pollution that focuses on CFCs

a. scrubber

b. catalytic converter

c. cap-and-trade

d. carbon sequestration

-->  e. Montreal Protocol

f. Kyoto Protocol

g. Clean Air Act

device that changes pollutants in exhaust gases to non-toxic compounds

a. scrubber

-->  b. catalytic converter

c. cap-and-trade

d. carbon sequestration

e. Montreal Protocol

f. Kyoto Protocol

g. Clean Air Act

worldwide agreement on air pollution that focuses on greenhouse gases

a. scrubber

b. catalytic converter

c. cap-and-trade

d. carbon sequestration

e. Montreal Protocol

-->  f. Kyoto Protocol

g. Clean Air Act

device that filters pollutants from exhaust gases

-->  a. scrubber

b. catalytic converter

c. cap-and-trade

d. carbon sequestration

e. Montreal Protocol

f. Kyoto Protocol

g. Clean Air Act

U.S. law that regulates six major air pollutants

a. scrubber

b. catalytic converter

c. cap-and-trade

d. carbon sequestration

e. Montreal Protocol

f. Kyoto Protocol

-->  g. Clean Air Act

removing carbon dioxide from the atmosphere and storing it in another form

a. scrubber

b. catalytic converter

c. cap-and-trade

-->  d. carbon sequestration

e. Montreal Protocol

f. Kyoto Protocol

g. Clean Air Act

system of limits and allowances on carbon dioxide emissions that can be exchanged between nations

a. scrubber

b. catalytic converter

-->  c. cap-and-trade

d. carbon sequestration

e. Montreal Protocol

f. Kyoto Protocol

g. Clean Air Act

diagram questions

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