Welcome to 4 th Quarter Chapter 13 Global Atmosphere.

Welcome to 4th QuarterChapter 13

Global Atmosphere

Announcements

• Grades

• Hours? 1st half, 4th quarter hours due April 16th

• TV - Environmental Documentaries ONLY!

• Science Nights and Seminar are good!

• T-SHIRT $$$$, please!!

Science Nights• March 29th – Westwood View

• April 10th - T.A. Edison (KCK)

• April 12th – Fiske (KCK)

• April 21st - Earth Fair @ SME

• April 28th - - SMSD R&D Forum

Chapter 13 Notebook1. Concept Review 20

2. Comparison Chart (notes) 15

3. Carbon Footprint 10

4. Global Warming Survival Guide 15

5. Video – The Signs and the Science 20

TOTAL 80

Global Atm. Comparison ChartCompare Climate Change to Ozone

depletionFor each, notes on the following..1. What gases are involved?2. How does the effect work?3. What are the possible consequences?4. How do we fix it?5. How are we doing?

Ozone depletion – global warming

• CFCs, Freon, chlorine

• CFCs move to the stratosphere and release chlorine atoms

• The chlorine atoms destroy ozone molecules

• Catalytic, 100,000 times per chlorine

• CO2, Methane, water vapor, nitrous oxides

• Sunlight warms the earth and bounces off as infrared.

• These gases trap infrared.

• Greenhouse effect is good, just to much of a good thing.

Consequences

• More UV gets through• Skin cancer, cataracts• Amphibian populations• Phytoplankton• Crop yields

• Disruption of weather• More droughts/floods• Crop yields• Ecosystem destruction,

(especially polar)• Sea level rise• Tropical diseases

Repair

• Stop production of CFCs• Wait 50 years

• Reduce carbon emissions from fossil fuels

• Sequester carbon• Cap and trade

Progress

• Montreal• But the CFCs are still on

their way. 50 year problem

• Kyoto• Not much progress

because of economic fears.

Ozone Depletion• Ozone is a pollutant at ground level but a

U.V. filter in the stratosphere.

• Ozone is formed in the stratosphere when high-energy ultraviolet radiation splits oxygen molecules.

• Ozone absorbs UVb. (biologically active)– UVa is harmless, UVc is deadly

Problem:• In the 1930s, the invention of CFCs allowed for

cheap refrigeration, and later, air conditioning.• Other uses added over the years• In 1970s, it was discovered that CFCs were

lowering the average concentration of Ozone in the stratosphere.– CFCs take 10-20 years to make it into the

stratosphere.• Can react with ozone for up to 120 years.

Sources of CFCs• Aerosols (spray cans)

• Foams (Styrofoam)

• Solvents (carbon tetra chloride)

• Air conditioning and refrigeration.

We no longer produce many CFCs

• CFC production has been phased out.

• Montreal Protocol in the name of the international agreement.

• The CFCs of the 80s are still there, as is the hole.

• (and the CFCs of the 90s are still on their way)

The ozone hole• Ozone depletion occurs most at the poles

where the “hole” forms

• Extends to the upper latitudes around the poles as it breaks up in the spring.

Mechanism of the Problem• In the stratosphere, UV radiation breaks

down CFC molecules, releasing atomic chlorine. A free Chlorine atom reacts with an ozone molecule, converting it from O3 to O2.

• One chlorine might destroy 100,000 ozone molecules

Ultraviolet light hits a chlorofluorocarbon (CFC) molecule, such as CFCl3, breakingoff a chlorine atom and leaving CFCl2.

UV radiation

Sun

Once free, the chlorine atom is off to attack another ozone moleculeand begin the cycle again.

A free oxygen atom pulls the oxygen atom off the chlorine monoxide molecule to form O2.

The chlorine atom and the oxygen atom join to form a chlorine monoxide molecule (ClO).

The chlorine atom attacksan ozone (O3) molecule, pulling an oxygen atom off it and leaving an oxygen molecule (O2).

Cl

Cl

ClC

F

Cl

Cl

OO

Cl

OO

O

Cl

O

OO

ClO

O

Summary of ReactionsCCl3F + UV Cl + CCl2FCl + O3 ClO + O2

Cl + O Cl + O2

Repeated many times

Dangers of Ozone Depletion• Skin Cancer, cataracts, weaken immune

response

• Crop Damage, reduced yields

• Destruction of plankton (and the aquatic food chain)

• Other wildlife, especially amphibians

Greenhouse Effect• Greenhouse gases allow sunlight to penetrate

the atmosphere.• Absorbed by earth’s surface.• Reradiated as infrared energy (heat).

– Absorbed by gases.

• This warming of the atmosphere keeps the earth from freezing solid every night.

• The issue is too much of a change, too fast.

– 100 million years of carbon released in a hundred.

0100,000200,000300,000400,000500,000600,000Age (yr BP)

300

500

400

600

180

200

220

240

260

280

Tem

p. in

F°

CO

2 C

on

centratio

n

Today’s CO2 Concentration

Projected Concentration After 50 More Years of Unrestricted Fossil Fuel BurningProjected Concentration After 50 More Years of Unrestricted Fossil Fuel Burning

CO

2 [

pp

mv]

Year

0

1850 1875 1900 1925 1950 1975 2000 2025 2050 2075 2100

0.5

1.0

1.5

2.0

2.5

3.0

3.5

4.0

4.5

5.0

5.5

6.0C

han

ge

in

te

mp

era

ture

(ºC

)

Greenhouse Effect

• Carbon Dioxide (70%)– Fossil fuel burning, land clearing.

• Chlorofluorocarbons (1%)– Refrigerants, cleaning solvents, propellants.

• Methane (10%)– Breakdown of organic material by anaerobic means.

• Nitrous Oxide (19%)– Biomass burning—Breakdown of nitrogen-rich

products.

Consequences of Global Warming

• Rising Sea Level– Beach and coastal wetland erosion.

• Disruption of Water Cycle– Navigation, Hydropower, Water Supply,

Recreation, Flood Control

• Worsening Health Effects– Expansion of tropical diseases

Consequences of Global Warming

• Changing Forests– Geographic distributions of vegetation.

• Challenges to Agriculture– Increased CO2 concentration likely to increase crop yields

in some areas and decrease yields in other areas.– Pest range expansion could increase vulnerability.

• Predictions based on computer models.

• Disruption of ecosystems – phenology

• Insects adapt and hatch earlier, birds, especially migratory ones, don’t.

• 3 species of penguins.

• The perm. resident is adapting and increasing.

• The 2 species that migrate to Antarctica to mate are declining.

• Increased deaths from heat and disease

• Disruption of food and water supplies

• Spread of tropical diseases to temperate areas

• Increased respiratory disease and pollen allergies

• Increased water pollution from coastal flooding

Human Health

• Rising sea levels• Flooding of low-lying islands

and coastal cities• Flooding of coastal estuaries,

wetlands, and coral reefs• Beach erosion• Disruption of coastal

fisheries• Contamination of coastal

aquifiers with salt water

Sea Level and Coastal Areas

• Changes in forest composition and locations

• Disappearance of some forests

• Increased fires from drying

• Loss of wildlife habitat and species

Forests

• Changes in water supply

• Decreased water quality

• Increased drought

• Increased flooding

Water Resources

• Shifts in food-growing areas

• Changes in crop yields

• Increased irrigation demands

• Increased pests, crop diseases, and weeds in warmer areas

Agriculture

• Extinction of some plant and animal species

• Loss of habitats

• Disruption of aquatic life

Biodiversity

• Prolonged heat waves and droughts

• Increased flooding from more frequent, intense, and heavy rainfall in some areas

Weather Extremes

• Increased deaths

• More environmental refugees

• Increased migration

Human Population

Addressing Climate Change

• Reduce Greenhouse Gas emissions.

• Improve energy efficiency.

• Increase amount of carbon dioxide removed from the atmosphere. (plants/sequestering)

• Use Bio-fuels instead of fossil fuels

• Halt deforestation

U.S. Emissions

0

0.5

1

1.5

2

2.5

3

1970 1990 2010 2030 2050

GtC

1.8

After Pacala and Socolow, 2004; ARI CarBen3 SpreadsheetAfter Pacala and Socolow, 2004; ARI CarBen3 Spreadsheet

2.6

Business as Usual

U.S. Stabilization

0

0.5

1

1.5

2

2.5

3

1970 1990 2010 2030 2050

GtC

2.6Electricity end-useefficiency

Other end-useefficiency

Passenger vehicleefficiency

Other transportefficiency

Renewables

CCS and Supplyefficiency

1.8

0.9


Arctic Sea Ice 1979

Arctic Sea Ice 2005

1932 1988

Boulder Glacier

• Glacier National Park

Photos: George Grant, Glacier National Archive; Jerry DeSanto, national Park Service

Before 1980

1983

1985

1989

1993

1996

1999

2001

Wastage ofColumbia Glacier

Alaska

Meier and Dyurgerov, Science, 297, 2002Aerial photo taken 1996

Rhone Glacier

Source: the Cheer Guild

Photo: AFP/Getty Images

Source: Yann ForgetSource: Yann Forget

U.S. Stabilization

0

0.5

1

1.5

2

2.5

3

1970 1990 2010 2030 2050

GtC

2.6Electricity end-useefficiency

Other end-useefficiency

Passenger vehicleefficiency

Other transportefficiency

Renewables

CCS and Supplyefficiency

1.8

0.9


Welcome to 4 th Quarter Chapter 13 Global Atmosphere.

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Transcript of Welcome to 4 th Quarter Chapter 13 Global Atmosphere.