Video Clip – Online Data & Concentric Circles

1. Video Clip – Online Data & Concentric Circles

2. Climate Change Climate Change & Man Made Global Warming

3. Definitions Weather: atmospheric conditions, including temperature, precipitation, wind, and humidity, in a particular location over a short period of time, such as a day or a week Climate: the average of the weather in a region over a long period of time

4. Let’s Talk Energy Supply... • The SUN provides the earth with all its energy. • Warms the Earth • Used by plants (photosynthesis)

5. Components of the Earth’s Climate System • The Atmosphere – Layers of gas • Ozone in Stratosphere protects from the sun’s harmful UV rays. • The Hydrosphere – Water, Water Vapour, Ice • Absorbs the sun’s energy • Water Cycle • The Lithosphere – Earth’s Crust (Land) • Absorbs the sun’s energy

6. Atmosphere • We can only survive in the Troposphere • Air in the troposhere is 78% N2, 21% O2 and 1% other gases including Ar, CO2, He, H and O3

7. High-energy radiation from the Sun enters the atmosphere. Gases and clouds in the atmosphere trap some of the infrared radiation from Earth’s surface and radiate it back. This is the Greenhouse effect.

8. Greenhouse Effect Video

9. Greenhouse Gases • Any gas in the atmosphere that absorbs infrared radiation from the Earth • Most of the air in the atmosphere is made of N2 and O2 which do not absorb radiation from the surface of the Earth • Greenhouses gases include H2O, CO2, CH4, N2O, CFC’s and a few others • They are very low in concentration • It is their concentration in the atmosphere which determines how much energy they can absorb

10. The Greenhouse Effect

11. This heat warms Earth’s atmosphere an average of 33°C • Eventually, this heat dissipates to outer space • If there were no greenhouse gases Earth’s average temperature would be -19°C

12. Greenhouse Gases • Consist of less than 1% of the atmosphere • Produced “naturally” and by human activities

13. Enhanced Greenhouse Effect (Humans increasing the Greenhouse Effect) • Humans are increasing the concentrations of greenhouse gases but by how much???

14. Water Vapour • Part of the “natural” greenhouse effect -HUMAN ACTIVITIES DO NOT RELEASE SIGNIFICANT AMOUNTS OF WATER VAPOUR INTO THE ATMOSPHERE -remains on average for 9 days • Most abundant greenhouse gas • Water vapor constitutes Earth's most significant greenhouse gas, accounting for about 95% of Earth's greenhouse effect

15. The Important Greenhouse Gases (except water vapor)U.S. Department of Energy, (October, 2000)(1) The Important Greenhouse Gases (except water vapor)U.S. Department of Energy

16. Nitrous oxide • Produced when wood and fossil fuels are burned • Produced by chemical industry and released by bacteria from fertilizers • Trap 296 times better than carbon dioxide

17. Carbon Dioxide • Released when fossil fuels- coal, oil and natural gas- are burned • Removal and burning of forests, industrial processes such as the manufacture of cement, and the cultivation of soil

18. The Remaining 5% • The remaining 5% is shown below. These charts shows human influence on the remaining 5% of greenhouse gases

19. Anthropogenic (man-made) Contribution to the "GreenhouseEffect," expressed as % of Total (water vapor INCLUDED) Anthropogenic (man-made) Contribution to the "GreenhouseEffect," expressed as % of Total (water vapor INCLUDED)

20. In Summary • Water vapor, responsible for 95% of Earth's greenhouse effect, is 99.999% natural (some argue, 100%). Even if we wanted to we can do nothing to change this. • Anthropogenic (man-made) CO2 contributions cause only about 0.117% of Earth's greenhouse effect • Adding up all anthropogenic greenhouse sources, the total human contribution to the greenhouse effect is around 0.28%

21. Global Warming and the Carbon Cycle However there is a general idea out there that an increase in CO2 is directly responsible for Global Warming. Why?

22. CO2 and Temperature

23. Where is all the Carbon? • Inorganic Carbon • The Atmosphere • The Ocean • The Earth’s Crust • Organic Carbon • Bodies of Living Things • Fossil Fuels

24. Where is all the Carbon? Most of the worlds Carbon is held in Carbon Sinks which is a reservoir, such as an ocean or forest, that absorbs carbon dioxide from the atmosphere and stores the carbon in another form

25. Human Impact on the Carbon Cycle • Humans affect the carbon cycle by: • releasing carbon into the atmosphere faster than would normally occur (burning fossil fuels/wood) • Clearing away vegetation (cutting down forests)

26. Human Impact on the Carbon Cycle

27. The Carbon Dioxide Positive Feedback Loop • Oceans are large Carbon sinks. As temperatures increase, more ocean water evaporates releasing the Carbon into the atmosphere which further increases the temperature

28. CO2 and Temperature

29. Effects of Global Warming • The impacts of climate change are predicted to be serious and widespread: • more violent weather • Increases in global temperatures  melting glaciers • shifting patterns of rainfall and drought • the spread of tropical diseases like malaria • rapid increasing extinctions of plant and animal species.

30. A growing body of evidence indicates that humans now have a significant impact on climate by affecting the carbon cycle.

31. Evidence of Climate Change • Earth’s average temperature has generally increased from 1880 to 2006. • What else could account for this increase?

32. Has abrupt climate change happened before?

33. YES

34. Long-Term Cycles in Climate • Over the last 800,000 years or more, Earth’s climate has cycled between freezing ice ages and warmer interglacial periods • We experience an Ice Age approximately every 100,000 years

35. Expected changes - Negative • Rising Sea Levels due to melting polar ice caps  Increased flooding • Agriculture Impacts  Less rain = less crops • Ecosystems  Creating unsuitable habitats (melting ice and polar bears) • Altered temperature and precipitation  less snow, more rain • Increase disease-carrying organism populations  increased disease rates (West Nile, Malaria, etc.)

36. Expected changes - Positive • An increase in temperature will decrease heating costs (energy usage) which will decrease CO2 emissions • Less ice coverage in Great Lakes  longer shipping seasons • Increase rain  decrease drought