1. Greenhouse Effect and Global Warming

2. Greenhouse Effect
The atmosphere is transparent to incoming solar radiation (short wave, high energy), but opaque to outgoing terrestrial radiation(longer waves, lower energy).
Black body radiator = perfect absorber and emitter or energy; wavelength depends on the temperature of the body.
Albedo = measure of reflectivity. For example, snow has a high albedo and asphalt has a low albedo.

3. Energy Balance

4. Greenhouse Gases Carbon dioxide – CO2 Water vapor – H2O Methane – CH4
Nitrous oxide – N2O
Freons – CFCs (totally anthropogenic)

5. Current GHG Concentrations
Updated September 2001

6. Global Warming
An increase in global temperatures due to increases in the concentrations of greenhouse gases
Appears to be a direct relationship between CO2 concentrations and increases in global temperatures
Relationship between CO2 and global temperatures was first noted in 1896 by Svante Arrhenius
NOT CAUSED BY STRATOSPHERIC OZONE DEPLETION

7. Causes Combustion of fossil fuels Deforestation Fertilizers CFCs
Slash and burn techniques release CO2
Fewer trees, less photosynthesis
Fertilizers
CFCs
Methane

8. Atmospheric carbon dioxide (CO2) concentrations (1750 to present)
Preindustrial atmospheric CO2 concentrations were approximately 275 parts per million. Today concentrations are approximately 367 ppmv, an increase of over 30 percent.
Data Source: C.D. Keeling and T.P. Whorf, Atmospheric CO2 Concentrations (ppmv) derived from in situ air samples collected at Mauna Loa Observatory, Hawaii, Scripps Institute of Oceanography, August A. Neftel et al, Historical CO2 Record from the Siple Station Ice Core, Physics Institute, University of Bern, Switzerland, September See
Data Source: C.D. Keeling and T.P. Whorf, Atmospheric CO2 Concentrations (ppmv) derived from in situ air samples collected at Mauna Loa Observatory, Hawaii, Scripps Institute of Oceanography, August A. Neftel et al, Historical CO2 Record from the Siple Station Ice Core, Physics Institute, University of Bern, Switzerland, September See

9. Cumulative carbon emissions, 1950-1996
In terms of historical contributions to the atmospheric buildup of emissions, the industrialized countries like the US have contributed roughly 80 percent of the carbon dioxide buildup in the atmosphere to date. On a country-by-country basis, the comparisons between the rich and poor countries are even more stark. Since 1950, the US has emitted a cumulative total of roughly 50 billion tons of carbon, while China (4.5 times more populous) and India (3.5 times more populous) have emitted only 15 and 4 billion tons respectively.
Data Source: Marland et al, Carbon Dioxide Information Analysis Center.
Data Source: Marland et al, Carbon Dioxide Information Analysis Center.

10. Variations in the Earth’s surface temperature

11. FACTORS AFFECTING GLOBAL TEMPERATURES
Incr. carbon dioxide  incr. temperature
Deforestation  Incr. carbon dioxide  incr. temperature
Incr. ocean temperature  incr. land temperature
Incr. particulate matterincr. albedo decr. temp.

12. Impacts Rise in sea level Climatic shifts Shifts in agriculture
Thermal expansion of the oceans
Melting ice caps and glaciers
Climatic shifts
Shifts in agriculture
Increase in disease
Declines in biodiversity
Coral bleaching

13. Potential Impacts of Global Warming
Increased deaths from heat and disease
Disruption of food and water supplies
Spread of tropical diseases to temperate areas
Increased respiratory disease
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
More intense hurricanes, typhoons, tornadoes, and violent storms
Weather Extremes
Increased deaths
More environmental refugees
Increased migration
Human Population

14. Sea Level Projections

15. Reducing GH Emissions

16. Solutions

18. Global Agreements
IPCC – Intergovernmental Panel on Climate Change  UNEP
Rio de Janeiro  1992
Kyoto Protocol  1997
Ratified Nov. 2006
U.S. and Australia have not signed the treaty

19. U.S. Position Bush Sr. (1988 – 1992) Clinton (1992 – 2000)
Bush Jr. (2000 – 2008)