1. It’s Gettin’ Hot in Here!

2. Key Points Greenhouse Gases-Review Global Warming CO2 Trends
Impacts of Greenhouse Gases
Reducing Greenhouse Gases
Global Cooling
The Carbon Cycle

3. Greenhouses Gases Review
Carbon Dioxide-
Man-made: burning of fossil fuels and deforestation
Natural: respiration and decomposition
Methane
Man-made: agriculture, livestock and polar ice melting
Natural: swamps and animal digestion
Tropospheric Ozone (not the ozone layer)
Man-made: Chemical reaction with N2O, VOC’s and Ultra violet light (from burning of fossil fuels)
Natural: tiny amounts released by plants and soil

4. Greenhouse Gases Review
Water Vapor
Caused by increased evaporation as temperatures rise
Nitrous Oxide
Man-made: synthetic fertilizers, transportation, industry (nitric acid production)
Natural: bacteria in soils, the ocean
Hydroflourocarbons
Man-made: created to replace CFC’s, found in refrigerants, aerosols, fire extinguishers
No natural source of hydrocarbons

5. GLOBAL WARMING What is global warming?
An increase in average global temperature
Carbon Dioxide:
Can stay in the atmosphere for more than 100 years.
Air contains 30% more CO2 than in 1700’s
Levels rising about .4% per year

6. Carbon Dioxide Trends
Carbon Dioxide Levels have been increasing steadily over the past 45 years
Over past 400,000 years: As CO2 increases, temperature increases and as CO2 decreases , temperature decreases.
What kind of relationship is this?

7. Impacts of Increasing Greenhouse Gases in the Atmosphere
Earth’s temperature will rise
Human health can be affected.
Good effects
Bad effects
Sea level will rise
Shores lines will erode
Flooding of the shores
Harm living things (other than humans)

9. Reducing Greenhouse Gases
Recycle
Decrease use of electricity
Alternative energy sources
Automobiles-use less often, carpool, fuel efficient, walk when possible, ride bikes when possible, electric cars.
Decrease deforestation
What else can we do?

10. Climate Change is not just about warming the climate!
Cooling the climate is also called climate change
What events can change the climate and make it cooler?

11. Natural Ways of Changing Climate and making it COOLER GLOBAL COOLING
Volcanic Eruptions
Meteorite Impacts
Changes in how much sunlight reaches the Earth

12. The Carbon Cycle All living things are made of carbon.
When carbon is in the atmosphere, it is attached to oxygen as CO2.
Plants use CO2 and sunlight to make food, and the carbon becomes part of the plant.
Plants either get eaten and the carbon transfers to the new organism, or they die and can become fossil fuels over millions of years.

13. The Carbon Cycle
When humans burn fossil fuels, they become CO2 back up in the atmosphere again.
Excess CO2 gets absorbed by the ocean.
This can negatively impact the ocean ecosystem if too much CO2 is absorbed.
When humans cut down trees (deforestation), they are no longer able to absorb CO2 from the atmosphere.