Ch. 8.2 Air Pollution and Solutions

Essential Question:

How Do People use Earth’s Resource?

What Causes Outdoor and Indoor Air Pollution?

What Causes damage to the Ozone Layer?

How can Air Pollution be Reduced?

Pgs. 260-269

Land, Air, and Water ResourcesMs. De Los Rios

7th Grade

Vocabulary1. Emissions- are pollutants released into the air.

2. Photochemical smog- is thick brownish haze formed when certain gases in the air react with sunlight.

3. Ozone- a form of oxygen that has 3 oxygen atoms in each molecule instead of the usual 2 (toxic to organisms where it forms near Earth’s surface.)

4. Temperature inversion- a layer of warm air prevents rising air from escaping.

5. Acid rain- precipitation that is more acidic than normal because of air pollution.

6. Radon- is a colorless odorless gas that is radioactive.

7. Ozone layer- the layer of the upper atmosphere about 30 km above Earth’s surface

8. Chlorofluorocarbon- (CFC) human made gases containing chlorine and flourine that are the main cause of ozone depletion.

What Causes Outdoor and indoor Pollution? Pg. 261

Outdoor Air Pollution

You can’t see it, taste it, or smell it, but you are surround it by it! What is it?

AIR

• ____ is a mixture of gases that cycle between living things and the atmosphere.

• Emissions are pollutants released into the air.

A large source of emissions resulting in air pollution outdoors comes from motor vehicles such as cars and

trucks. • In addition, factories, power plants, and

natural sources (methane from cows) cause air pollution. r. last p

Smog pg. 262

Photochemical smog is a thick, brownish haze formed when certain gases in the air react with sunlight.

It can cause:

breathing problems

eye and throat irritation

The major sources of smog are the gases emitted by cars & trucks

• These gases react in the sunlight and produce ozone, a toxic form of

oxygen.• Ozone can cause:

Lung inf. & damage the body’s defenses against infections.

Smog pg. 262

Temperature inversion- a layer of warm air prevents rising air from escaping.

During Temperature inversion, a layer

of warm air prevents the rising air from

escaping. The polluted air is trapped

and held close to Earth’s surface. The

smog becomes concentrated and

dangerous.

Figure 2

Acid Rain pg. 263

Precipitation that is more acidic than normal because of air pollution is called

acid rain.

Acid rain damages plants, waterways, and metals and stones.

Acid rain can also take form of:

Snow, sleet, or fog

A.R. is caused by:

Power plants & factories that burn coal and oil that produce nitrogen oxides and sulfur oxides when they are burned.

r. Pg 263

Apply iT!!!!

Fig. 3In the text underline the

cause of acid rain.

Indoor Air PollutionIndoor air pollution has many

sources.

Air Pollution and Solutions pg. 264

Even indoor air can be polluted. Some substances that cause indoor air pollution, such as dust and pet hair, bother only those people who are sensitive to them. Other indoor air pollutants, such as toxic chemicals, can affect anyone. Radon is a colorless, odorless gas that is radioactive.

Assess your Und.

Fig. 4Circle the sources of indoor

air pollution in this room.

Ozone CycleThe ozone cycle prevents harmful ultraviolet

radiation from reaching Earth’s surface.

The ozone layer is a layer of the upper atmosphere about 30 kilometers above Earth’s surface. It protects people from the effects of too much ultraviolet radiation. (protects people from sunburn, eye disease, & skin cancer)

Ozone is a pollutant (r. p. 2/3)

Ozone is constantly being made and destroyed as part of the ozone cycle. Each time the cycle occurs, UV energy

Is absorbed!

Read Fig. 5

Fig. 5 Air Pollution and Solutions pg. 265

Cycle begins here

What Causes Damage to the Ozone Layer? pg. 265

• The amount of ozone in the ozone layer is decreasing, creating an ozone hole. Scientists determined that the major cause of the ozone hole is a group of gases called chlorofluorocarbons, CFCs.

• Chlorofluorocarbon- (CFC) human made gases containing chlorine and flourine that are the main cause of ozone depletion. Sprays, a/c, household products contain CFCs. Most uses of CFCs were banned in 2000.

Ozone and Ultraviolet Radiation

The amount of ozone in the atmosphere and the amount of UV radiation reaching Earth

are linked.

1.Label which curve represents ozone and which represents UV radiation?

2. Explain the graph in your own words. ____________________________________________________________________________________

Fig. 7 266 Air Pollution and Solutions pg. 266

What’s Being Done pg. 267

• Ban on CFCs products 2000

• Some products are still allowed

• CFC molecules remain in the atmosphere

• Scientist predict that ban will allow the ozone layer to gradually

recover

• Researcher have develop ways to make products without using CFCs

• The substitutes that were developed, are less harmful than CFCs

How Air Pollution Can be Reduced?

The key to reducing air pollution is to control emissions.

• Factories and vehicles use devices and systems to reduce emissions.

• Individuals can reduce air pollution by using electricity and motor vehicles less.

Figure 8

Where Does an Apple Really Come From?

Many things in our everyday lives, even where food comes from, can contribute to air pollution.

Fig. 9 Air Pollution and Solutions pg. 269

Air Pollution and Solutions pg. 269

Analyze Costs and BenefitsWhat are the pros and cons of buying apples that were grown

locally instead of those grown in another country?

Assess your Und.

I know the key to reducing air pollution is_____________________________________________________________________________________