8.2 Air Pollution and Climate

8.2 Air Pollution and Climate

4/25/23 Ms. Havu, Environmental Science

Open Ended

Why is carbon dioxide not considered a primary pollutant?

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8.2 Air Pollution and the Climate

Physical processes in the atmosphere transport,
concentrate, and disperse air pollutants.

Global warming, in which pollutants are altering the
earth’s energy budget, is the best-known case of
interaction between anthropogenic pollutants and
the atmosphere.

In this section we survey other important
climate-pollution interactions.

Multiple Choice

In global warming, pollutants are altering the Earth's...

• natural resources

• energy budget

• shape

• size

Multiple Choice

What does "anthropogenic" mean?

• Natural

• Human-made

• Animal-like

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Air Pollutants Travel the Globe

Air pollutants can travel far:

• Dust and fine aerosols can be carried great

distances by the wind.

• Pollution from the industrial belt between the

Great Lakes and the Ohio River Valley regularly
contaminates the Canadian Maritime Provinces
and sometimes can be traced as far as Ireland.

• Similarly, dust storms from China’s Gobi and

Takla Makan Deserts routinely close schools,
factories, and airports in Korea, Japan, and even
Seattle in the U.S.

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Dust Blowing From the Sahara

Dust from North Africa
regularly crosses the
Atlantic and contaminates
the air in Florida and the
Caribbean Islands.

This dust can carry
pathogens and is thought to
be the source of diseases
attacking Caribbean corals.

Image courtesy of Norman Kuring, SeaWiFS Project

Multiple Choice

Dust and aerosols can be carried great distances by...

• wind

• water

• animals

• sunlight

Multiple Choice

What states are most affected by dust and fine aerosols carried by winds from other countries?

• Florida

• Washington

• Florida and Washington

• Pennsylvania

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Carbon Dioxide and Halogens

Are Key Greenhouse Gases

CO2 concentrations in the atmosphere have been
steadily increasing due to human activities and are
now causing global climate change, but it is not alone
as a greenhouse gas. Five other greenhouse gases
are : methane, nitrous oxide, hydrofluorocarbons,
perfluorocarbons and sulfur hexafluoride.

These gases are far more potent greenhouse gases
per molecule than CO2 and since the recent Supreme
Court ruling, the EPA is charged with regulating
emissions of all these gases.

Multiple Choice

All of the following are greenhouse gases EXCEPT:

• Methane

• Nitrous oxide

• Carbon monoxide

• Hydro-fluorocarbon

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CFCs Also Destroy Ozone

in the Stratosphere

Chemical reactions of
atmospheric gases and
pollution produce the
phenomenon known as the
ozone hole.

Chlorine-based aerosols,
such as CFC’s and HCFC’s,
are the principal agents of
ozone depletion.

Excessive UV exposure
could cause cancer, reduce
agricultural production and
disrupt ecosystems.

NASA

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Greenhouse Gases

Multiple Choice

According to the graph, which pollutant has the HIGHEST effect on global warming per molecule?

• Methane

• Nitrous Oxide

• Carbon Dioxide

• HFC-23

Multiple Choice

According to the graph, which pollutant has the LEAST effect on global warming per molecule?

• Methane

• Nitrous Oxide

• Carbon Dioxide

• HFC-23

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CFC Control has Shown

Remarkable Success

In 1987 an international meeting in Montreal,
Canada, produced the Montreal Protocol, the first of
several major international agreements on phasing
out most uses of CFCs by 2000.

As evidence accumulated, showing that losses were
larger and more widespread than previously thought,
the deadline for the elimination of all CFCs was
moved up to 1996.

CFCs are now being removed from the atmosphere
more rapidly than they are being added.

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Success of the Montreal Protocol

Multiple Choice

What is the reason the Montreal Protocol was considered a success?

• CFC levels started to lower after 1986

• CFC levels increased after 1986

• CFC levels started to decrease after 1988

• CFC levels started to increase after 1988