1. Regional and Global Atmospheric Changes
Chapter 21
Regional and Global Atmospheric Changes

2. Global Climate Change

3. Energy Balance and Planetary Temperature
Venus- surface temps hot enough to melt Pb
Mars – surface temps -> all water is frozen
Earth – climate in which life has evolved

4. Energy Balance and Planetary Temperature
All objects emit energy in the form of light
Wavelengths of emitted energy depend on the objects temperature
In order for a planet to remain at a constant average temperature, the total energy radiated from its surface (and atmosphere, if any) must equal the total energy absorbed from the sun.

5. Predicted Planetary Temperature
Not all incoming energy is absorbed by earth’s surface
Some is reflected by the atmosphere and surface
Ratio of reflected energy to incoming energy = albedo
White surface  100 % albedo
Black body  0 % albedo

6. Predicted Planetary Temperature
Predicted temps based on comparison of energy absorbed and energy emitted by a black body

7. Atmospheres and Planetary Temperature

8. Atmospheres and Planetary Temperature

9. Greenhouse Gases
“Is the mean temperature of the ground in any way influenced by the presence of heat- absorbing gases in the atmosphere?” —Svante Arrhenius, 1896

10. Greenhouse Gases Global Warming Potential It depends on 3 factors:
a measure of how much energy a greenhouse gas would add to atmospheric warming in a given time compared to CO2
It depends on 3 factors:
IR wavelengths absorbed
The strength of absorption
Lifetime in the atmosphere

11. Greenhouse Gases Global Warming Potential CO2 1 CH4 12 N2O 114
CCl2F
CHF
CH2FCF3 14 SF

12. Global Climate Change
The Causes of Global Climate Change

13. Global Climate Change The Causes of Global Climate Change
CO2 in the atmosphere

14. The Role of the Oceans
The earth’s average surface temp. has increased by ~ 1oC since the beginning of the 20th century.
From , the avg. temp. of the top 2000m of the ocean has increased 0.09oC

15. The Role of the Oceans Ocean Chemistry CO2(g) <==> CO2(aq)
CO2(aq) + H2O <==> HCO3–(aq) + H+(aq)
HCO3–(aq) <==> CO32–(aq) + H+(aq)
Addition of CO2, results in a decrease in pH

16. Ocean acidification due to increasing atmospheric carbon dioxide
30 Jun Carbon dioxide (CO2) emitted to the atmosphere by human activities is being absorbed by the oceans, making them more acidic (lowering the pH the measure of acidity).
Evidence indicates that emissions of carbon dioxide from human activities over the past 200 years have already led to a reduction in the average pH of surface seawater of 0.1 units and could fall by 0.5 units by the year This pH is probably lower than has been experienced for hundreds of millennia and, critically, at a rate of change probably 100 times greater than at any time over this period.
The report outlines our best understanding of the impacts of these chemical changes on the oceans. The impacts will be greater for some regions and ecosystems, and will be most severe for coral reefs and the Southern Ocean. The impacts of ocean acidification on other marine organisms and ecosystems are much less certain. We recommend a major international research effort be launched into this relatively new area of research.
We recommend that action needs to be taken now to reduce global emissions of CO2 from human activities to the atmosphere to avoid the risk of irreversible damage from ocean acidification.

17. 'Only 50 years left' for sea fish
Thursday, 2 November 2006
There will be virtually nothing left to fish
from the seas by the middle of the century
if current trends continue, according to a major
scientific study.
Stocks have collapsed in nearly one-third of sea fisheries, and the rate of decline is accelerating.
Catch records from the open sea give a picture of declining fish stocks.
In 2003, 29% of open sea fisheries were in a state of collapse, defined as a decline to less than 10% of their original yield.

18. Evidence of Climate Change
Temperature Increase
Many studies have shown that the earth’s temperature is increasing.
Includes measurements of land surface, sea surface, or a combo of both temperatures.

19. Evidence of Climate Change

20. Evidence of Climate Change

21. Evidence of climate Change

22. Evidence of Climate Change
Changes in precipitation

23. Evidence of Climate Change

24. Evidence of Climate Change

25. Evidence of Climate Change

26. Evidence of Climate Change
Melting Glaciers (Qori Kalis Glacier, Peru)
2004
1978

27. Evidence of Climate Change
Grinnell Glacier, Glacier Nat'l Park, 1940
Grinnell Glacier, Glacier Nat'l Park, 2006
Source: NOAA
Melting Glaciers

28. Evidence of Climate Change

29. McCall Glacier, Alaska, 1958 and 2003

30. Evidence of Climate Change
Melting Land Ice (Greenland)

31. Evidence of Climate Change
Melting Sea Ice
Artic Sea ice has decreased rapidly in the last 3 decades
2012
1980

33. Evidence of Climate Change
Effects of melting sea ice
Loss of albedo  increased absorption of energy (positive feedback)
Decrease in salinity  potential disruption in ocean circulation patterns

34. Evidence of Climate Change
Increase in Sea levels
Thermal expansion
Melting glaciers and land ice

35. Evidence of Climate Change

36. Evidence of Climate Change

37. Evidence of Climate Change
Wildfires
Increases in temperature results in increased evaporation/transpiration and changes in precipitation patterns
As of August 21, 2012

38. Evidence of Climate Change
Increase in frequency and severity of droughts

39. Evidence of Climate Change
Storm severity and frequency

42. Evidence of Climate Change
Changes In Biomes

43. Evidence of Climate Change
Effects on agriculture

44. Evidence of Climate Change
Effects on agriculture

45. Evidence of Climate Change
Changes in Biodiversity
Shifting biomes (up mountain slopes and further north/south)
Die-offs (coral, fish)
Extinctions
Life cycles
Physiology
migration

46. By a wide margin, 2012 was the United States’ warmest year on record (NOAA)

47. By a wide margin, 2012 was the United States’ warmest year on record (NOAA)
“2012 marked the warmest year on record for the contiguous United States with the year consisting of a record warm spring, second warmest summer, fourth warmest winter and a warmer-than-average autumn. The average temperature for 2012 was 55.3°F, 3.3°F above the 20th century average, and 1.0°F above 1998, the previous warmest year.” “The average precipitation total for the contiguous U.S. for 2012 was inches, 2.57 inches below average, making it the 15th driest year on record for the nation.”

48. By a wide margin, 2012 was the United States’ warmest year on record (NOAA)
“The U.S. Climate Extremes Index indicated that 2012 was the second most extreme year on record for the nation. The index, which evaluates extremes in temperature and precipitation, as well as landfalling tropical cyclones, was nearly twice the average value and second only to To date, 2012 has seen 11 disasters that have reached the $1 billion threshold in losses, to include Sandy, Isaac, and tornado outbreaks experienced in the Great Plains, Texas and Southeast/Ohio Valley.”

50. Global Climate Change The Causes of Global Climate Change
Enhanced Greenhouse Effect

51. Global Climate Change Effects of Global Climate Change
Melting Ice and Rising Sea Levels
1957
1998

52. Global Climate Change Effects of Global Climate Change
Melting Ice and Rising Sea Levels

53. Global Climate Change Effects of Global Climate Change
Melting Ice and Rising Sea Levels
Melting permafrost

54. Global Climate Change Effects of Global Climate Change
Changes in Precipitation Patterns

55. Global Climate Change Effects of Global Climate Change
Effects on Organisms
Present range of beech trees
Predicted range after climate change

56. Global Climate Change Effects of Global Climate Change
Effects on Human Health

57. Global Climate Change Effects of Global Climate Change
Effects on Agriculture
- Current farmlands could be rendered unusable
- Location of crop types could be shifted

58. Global Climate Change Effects of Global Climate Change
Global Climate Change May Cause Unforeseen Events
- Disruption of the ocean conveyor belt
(could induce “ice age” in Europe)

59. What can we do?

60. What can we do? CO2 concentrations: 275 ppm – pre-industrial period
392 ppm – current levels
350 ppm – goal estimated by Hansen et. al. as safe upper limit

61. What can we do? Reduce usage of fossil fuels (coal, oil, natural gas).
Electricity Generation in the US
Use alternative energy sources
Improve energy efficiency

62. Alternative Energy Sources
Solar power
Wind
Tidal/Wave
Nuclear
Hydro-power

63. Improving Energy Efficiency
Improving fuel economy for cars, buses, and trucks.
Electric vehicles
Increasing use of public transportation
Energy efficient appliances
Energy efficient homes/schools/businesses

64. Geo- engineering Sequester carbon in trees.
Fertilize the ocean with iron
Releasing aerosol particles to the atmosphere

65. Adaptation Move farms to more suitable geographic regions????
Build flood protection (seawalls, levee’s, etc.)
Relocation of coastal residents
Development of alternative water sources (desalinization)

66. Government Action
Kyoto Protocol – United Nations Framework Convention on Climate Change
Signed by 192 countries
Signed, but not ratified by the US
Binding CO2 reductions for developed countries.
No limits set for developing countries