1. 6.1.1 Global Warming

2. Global Warming & Greenhouse Gases

4. Greenhouse Effect Constant temperature:
incoming solar energy = outgoing solar energy
Greenhouse gases found in the troposphere absorb some of the infrared radiation (heat) radiated by the earth’s surface.
Gas molecules vibrate more  heat

5. Temperature and Carbon Dioxide Concentration.

6. Greenhouse Gases** Water Vapor (varies) Carbon Dioxide (50%)
Methane (16%)
Nitrous Oxide (6%)
CFCs (20%)
Ozone (8%)
Miller p.449

7. Water Vapor Most abundant natural greenhouse gas.
Contributes to heating of the ocean surface and the lower atmosphere.
Higher temps = more evaporation = rising of water vapor = more warming.

8. Carbon Dioxide (CO2) Present naturally (0.037%).
Increased since Industrial Revolution
Combustion of fossil fuels (coal, natural gas & petroleum).
For every kg of fossil fuels burned 3kg is released.
Deforestation
Fewer forests = less absorption of CO2.

9. Methane (CH4)
More effective (30x) absorber of long wave radiation than CO2.
Sources
Landfills
Agriculture: intestines of cattle and sheep
Wetlands, swamps, bogs
Coal mines and natural gas
Is being added to the atmosphere faster than it can be broken down.
Increase correlates with population increase.

10. Nitrous Oxide (N2O) Agriculture Source
Consequence of anaerobic dentrification processes
Fertilizing land
Industrial source: High temperature combustion of fossil fuels.

11. CFC’s and other Halocarbons
Concerns:
Live long and contribute to warming and greenhouse effect
Also deplete ozone
Absorb 10,000 times more radiation than CO2
Sources:
Foam
Cleaners
Aerosol sprays
Coolants for refrigeration and air conditioning

14. Consequences

15. Melting Ice Caps

17. Spread of human disease:

18. global conveyor belt

19. **

20. Island Inundation

21. Habitats are becoming compromised

22. Methane bubbles trapped in lake ice in early autumn Credit: Katey Walter; courtesy of Nature

23. The Debate

24. Ways to Reduce Greenhouse Gas Emissions
1. Do not burn fossil fuels:
Use renewable energy sources:
Wind power
Solar power
Geothermal energy
Alternatives don’t emit greenhouse gases.

25. 2. Replanting Forests.
3. Recycling and reuse.

26. 4. Legislation: Stricter transportation laws
Carbon Tax
Carpool & HOV lanes (High Occupancy Vehicles)
Use Mass transit
High-mileage standards

27. Sea Level and Coastal Areas
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

28. Action CO2 Reduction Drive fuel-efficient car, walk, bike,
car pool, and use
mass transit
Use energy-efficient
windows
refrigerator
Insulate walls
and ceilings
Reduce garbage
by recycling
and reuse
Caulk and
weatherstrip
windows and doors
Insulate hot water
heater
Use compact
fluorescent bulbs
Set water heater
at no higher than
(120° F)
Wash laundry in
warm or cold water
Use low-flow
shower head
9 kg (20 lbs)
per gallon of
gasoline saved
Up to 4,500 kg
(10,000 lbs) per year
Up to 1,400 kg
(3,000 lbs) per year
Up to 900 kg
(2,000 lbs) per year
450 kg (1,000 lbs)
for 25% less
garbage per year
Up to 450 kg
(1,000 lbs) per year
230 kg (500 lbs)
per year per bulb
for each 6° C
(10° F) reduction
Up to 230 kg
(500 lbs) per year
for 2 loads a week
Up to 140 kg
(300 lbs) per year