1. Climate Change Weather vs. Climate Earth’s energy supply
The atmosphere
Greenhouse gases
The greenhouse effect
Enhanced greenhouse effect
The role of the carbon cycle
Effects of global warming
Historic climate change
Climate proxies
What you can do

2. Weather vs. Climate
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

3. Air Convection Currents
Large convection air currents occur over the world because cool air is more dense than warm air.
These convection currents
can greatly affect the
weather in a given region.

4. Air Currents and Large Bodies of Water
During the summer, large bodies of water absorb a lot of heat
This will cause the climate to be more moderate in summer near the coast.
In winter, the water near the coast will slowly release this energy,
This will cause coastal areas to be less cold, in general, than inland areas in the winter.

5. Let’s Talk Energy Supply...
The SUN provides the earth with most of its energy.
Warms the Earth
Used by plants (photosynthesis) to produce carbohydrates (glucose)

6. 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)

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

8. The Ozone Layer
The Ozone (O3) Layer is located between the stratosphere and the troposphere and helps protect us from UV light from the sun.
Ozone depletion is caused by human-made compounds called chlorofluorocarbons (CFC’s)
Many CFCs have been widely used as refrigerants and propellants (in aerosol applications). Their manufacture has been phased out due to their harmful affects.

9. High-energy radiation from the Sun enters the atmosphere
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.

10. Infrared (long-wave) Radiation

11. The Greenhouse Effect

12. 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

13. Greenhouse Gases
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

14. The Greenhouse Effect

15. The Greenhouse Effect
The heat from the natural greenhouse effect warms Earth’s atmosphere an average of 33°C
Eventually, this heat dissipates to outer space
If there were no greenhouse effect, Earth’s average temperature would be -19°C

16. End of Day 1

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

18. Enhanced Greenhouse Effect (Human impact on the Greenhouse Effect)
Humans are increasing the concentrations of greenhouse gases but by how much???
What impact do we have?
What is the greenhouse effect?

19. Water Vapour (95% of Earth’s greenhouse effect)
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

20. The Important Greenhouse Gases (except water vapor) U. S
The Important Greenhouse Gases (except water vapor) U.S. Department of Energy
(all concentrations expressed in parts per billion)
Pre-industrial baseline
Natural additions
Man-made additions
Total Concentration (ppb)
Percent of Total
 Carbon Dioxide (CO2)
 288,000
68,520 
11,880
368,400 
99.438% 
 Methane (CH4)
 848
577 
320 
1,745 
0.471% 
 Nitrous Oxide (N2O)
 285
12 
15 
312 
0.084% 
 Misc. gases ( CFC's, etc.)
 25 0  2
27 
0.007% 
 Total
 289,158
69,109 
12,217 
370,484 
100.00% 
Think about it:
What is the most abundant gas?
Which gas do you think will have had the largest % increase (total) post industrial revolution?
Which has had the largest % increase (total) post industrial revolution?

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

22. Carbon Dioxide
Released when fossil fuels- coal, oil and natural gas- are burned
Increases due to the removal and burning of forests, industrial processes such as the manufacture of cement, and the cultivation of soil

23. The Remaining 5%
Water vapor accounts for about 95% of Earth's greenhouse effect
The remaining 5% is shown below. These charts shows human influence on the remaining 5% of greenhouse gases

24. Based on concentrations (ppb)
Anthropogenic (man-made) Contribution to the "Greenhouse Effect," expressed as % of Total (water vapor INCLUDED)
Based on concentrations (ppb)
 % of Greenhouse Effect
% Natural
% Man-made
 Water vapor
95.000% 
 94.999%
0.001% 
 Carbon Dioxide (CO2)
3.618% 
 3.502%
0.117% 
 Methane (CH4)
0.360% 
 0.294%
0.066% 
 Nitrous Oxide (N2O)
0.950% 
 0.903%
0.047% 
 Misc. gases ( CFC's, etc.)
0.072% 
 0.025%
 Total
100.00% 
 99.72
0.28% 

25. In Summary
 Water vapor which is responsible for 95% of Earth's greenhouse effect, is 99.999% natural. 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 gas sources, the total human contribution to the greenhouse effect is around 0.28% .

26. Global Warming and the Carbon Cycle
However the general consensus is that an increase in CO2 is directly responsible for Global Warming. Why?

27. CO2 and Temperature

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

29. 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 (H2CO3)

30. 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).

31. Human Impact on the Carbon Cycle

32. 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. This then repeats.

33. CO2 and Temperature

34. End of Day 2

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

36. Who Cares???

37. 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, increase in sea levels, flooding
Ecosystems  Creating unsuitable habitats (melting ice and polar bears)
Shifting patterns of rainfall and drought

38. 1928 South Cascade Glacier, Washington
A growing body of evidence indicates that humans now have a significant
impact on climate by affecting the carbon cycle.

39. Why? Look it up.
An increase in global temperature will create in increase in disease-carrying organism populations like certain types of mosquitoes which will lead to increased disease rates such as West Nile, Malaria, etc.).

40. Human Health
“Worldwide increases in the incidences of asthma, allergies, infectious and cardiovascular diseases will result from a variety of impacts of global climate change, including rising temperatures, worsening ozone levels in urban areas, and expansions of the ranges of communicable diseases as the planet heats up”

41. 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

42. Has abrupt climate change happened before?

43. YES

44. 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

45. Prehistoric Climate Changes
Climate proxies are preserved physical characteristics of the past that enable scientists to reconstruct historic climate conditions
Examples include:
Pollen records
Ice core samples
Marine corals
Fossils

46. What can you do? Make a List
Choose reusable products
Use less heat and air conditioning
Buy energy-efficient products
Drive less
Turn lights off
Buy local products
Plant a tree
Etc.