History of Earth

• Earth formed ~4.6 billion years ago

• Originally very hot

• Sun’s energy output only 70% of present

• Liquid water present ~4.3 billion years

Earth’s Atmospheric Gases

Nitrogen (N2)

Oxygen (O2)

Water (H2O)

Carbon Dioxide (CO2)

Methane (CH4)

Non-Greenhouse

Gases99%

GreenhouseGases

1%

Global Warming

• Global warming is when the earth heats up (the temperature rises).

• It happens when greenhouse gases (carbon dioxide, water vapor, nitrous oxide, and methane) trap heat and light from the sun in the earth’s atmosphere, which increases the temperature.

Global Warming - Examples

1914 2004

Greenhouse EffectSun

• The greenhouse effect is when the temperature goes up, on Earth, since the sun’s heat and light energy is trapped in the earth’s atmosphere.

• While the heat from the sun enters our atmosphere, the heat has trouble leaving back out our atmosphere

Greenhouse Effect

Greenhouse Gases

Water

Carbon dioxide Sulfur hexafluorideNitrous oxide

Methane

CO2 | NH4 | N20

Control on Greenhouse Gases

Small changes really add up

Replace your old refrigerator with a new Energy Star: Annual savings: $90; 700 pounds CO2

Set your thermostat down a few degrees in the winterAnnual savings: $135; 1400 pounds CO2

Wash clothes in cold water onlyAnnual savings: $70; 500 pounds CO2

Drive JUST 10 fewer miles per weekAnnual savings: $80; 520 pounds CO2

Reduce your garbage by 10% through greater recycling or reduced packagingAnnual savings: 1200 pounds CO2

Replacing just 1 incandescent light bulb with 1 compact florescent bulb saves about 150 pounds of carbon dioxide per year!

Our take-home message…Save the WORLD its your home

No single technology will stop global warming, but there is a silver bullet: a cap on carbon that will launch all these solutions into the mainstream