Regional and Global Atmospheric Changes

1. Chapter 21 Regional andGlobal AtmosphericChanges

4. Global Climate Change • Mean annual global temperature,1960–2003

5. Global Warming Slideshow • http://www.nwf.org/globalwarming/whatisglobalwarming/ Greenhouse gases absorb the suns energy, thereby allowing less heat to escape back to space, and 'trapping' it in the lower atmosphere. Many greenhouse gases occur naturally in the atmosphere, such as carbon dioxide, methane, water vapor, and nitrous oxide, while others are synthetic.

6. Global Climate Change • The Causes of Global Climate Change

7. Water Vapor is the most abundant greenhouse gas in the atmosphere. However, changes in its concentration is also considered to be a result of climate feedbacks related to the warming of the atmosphere rather than a direct result of industrialization. Concentrations of ozone have risen by around 30% since the pre-industrial era, and is now considered by the IPCC to be the third most important greenhouse gas after carbon dioxide and methane.

8. Global Climate Change • The Causes of Global Climate Change • CO2 in the atmosphere humankind has altered the natural carbon cycle by burning coal, oil, natural gas and wood and since the industrial revolution began in the mid 1700s, each of these activities has increased in scale and distribution.

10. Methane (CH4) is a greenhouse gas that remains in the atmosphere for approximately 9-15 years. Methane is over 20 times more effective in trapping heat in the atmosphere than carbon dioxide (CO2) over a 100-year period and is emitted from a variety of natural and human-influenced sources Methane is an extremely effective absorber of radiation, though its atmospheric concentration is less than CO2 and its lifetime in the atmosphere is brief (10-12 years), compared to some other greenhouse gases (such as CO2, N2O, CFCs).

12. Global Climate Change • The Causes of Global Climate Change • Enhanced Greenhouse Effect

13. The Intergovernmental Panel on Climate Change (IPCC) reports that the average surface temperature of the earth increased nearly1.4°F in the 20th century, due primarily to human caused global warming. • The IPCC projects a 3.2-7.2 degrees Fahrenheit in the 21st century, depending upon the extent to which global warming pollution is dramatically reduced.

14. On average, eleven of the past twelve years (1995–2006) rank among the twelve warmest years on record since 1850 • Don't Blame Sun for Global Warming, Study Says Brian Handwerkfor National Geographic News • September 13, 2006

15. National Geographic Article • "There has been an intuitive perception that the sun's variable degree of brightness—the coming and going of sunspots for instance—might have an impact on climate," Foukal said • sunspot-driven changes to the sun's power are simply too small to account for the climatic changes observed in historical data from the 17th century to the present, research suggests. • The difference in brightness between the high point of a sunspot cycle and its low point is less than 0.1 percent of the sun's total output.

16. Global Climate Change • Other Pollutants Cool the Atmosphere • Specifically, the aerosol effect • Caused by sulfur emissions

17. Global Climate Change • Developing Climate Models

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

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

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

21. The average sea level is expected to rise 7–23 inches before the end of this century, and perhaps as much as 31 inches over that time if the rate of ice melt from Greenland and Antarctica increases as some models predict.

22. Global Climate Change • Effects of Global Climate Change • Changes in Precipitation Patterns

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

24. Global Climate Change • Effects of Global Climate Change • Effects on Human Health

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

26. Global Climate Change • Effects of Global Climate Change • Climate Change May Cause - Disruption of the ocean conveyor belt (could induce “ice age” in Europe) http://news.nationalgeographic.com/news/2005/11/1130_051130_ice_age.html

27. Global Climate Change • International Implications of Global Climate Change • Highly Developed versus Developing Nations

28. Global Climate Change • International Implications of Global Climate Change • International Efforts to Reduce Greenhouse Gas Emissions - Kyoto Protocol (currently, not ratified by US)

29. Global Climate Change More greenhouse gases produced Greater impact on humans and natural environment • Specifics on How to Deal with Global Climate Change More serious climate change effects Less mitigation More adaptation required

30. Global Climate Change Less greenhouse gases produced Lesser impacts on humans and natural environment • Specifics on How to Deal with Global Climate Change Less serious climate change effects More mitigation Less adaptation required

31. Global Climate Change • Mitigation of Global Climate Change • Alternatives to fossil fuels • Sequestering Carbon in Trees • Carbon Management • Fertilizing the Ocean with Iron • http://www.ft.com/pp/bizcarbon

33. Global Climate Change • Adaptation to Global Climate Change • Coastal populations • move inland • construct levees • Adapt to shifting agricultural zones

34. Global Warning Video • http://www.leonardodicaprio.org/files/videos/globalwarning.html?q=whatsimportant/globalwarming_movie01.htm

35. Ozone Depletion in the Stratosphere Normal levels of ozone Reduced levels of ozone • Stratospheric ozone layer

37. Ozone Depletion in the Stratosphere • Ozone thinning

38. Ozone Depletion in the Stratosphere • The Causes of Ozone Depletion • Main problem: CFCs – • commonly called freons • Other chemicals: • Halons • Methyl bromide • Methyl chloroform • Carbon tetrachloride • Nitrous oxide

39. Ozone Depletion in the Stratosphere • The Effects of Ozone Depletion • Potentially, increased incidence of skin cancers Basal and Squamous Cell Carcinomas Malignant Melanoma

40. Ozone Depletion in the Stratosphere • Case-in-Point: Facilitating the Recovery of the Ozone Layer • Montreal Protocol stipulated a reduction in CFCs • At Montreal, the participants agreed to freeze production of CFCs at 1986 levels and to reduce production by 50% by 1999 • Smuggling CFCs remains a problem

41. Acid Deposition • AKA: Acid rain • In US, damage from acid deposition is estimated at $10 billion • http://www.5min.com/Video/Environmental-Issues-Acid-Rain-1354359

42. Acid Deposition • Measuring Acidity

43. Acid Deposition • How Acid Deposition Develops

44. Acid Deposition • The Effects of Acid Deposition • Acid Deposition and Forest Decline

45. Acid Lakes In the Adirondack region, acidic deposition has affected hundreds of lakes and thousands of miles of headwater streams. The diversity of life in these acidic waters has been greatly reduced. Fish populations have been lost, and loons and otters have moved to other lakes where they can find food

46. Acid Deposition

47. Acid Deposition • The Politics of Acid Deposition • Acid deposition not limited to locations where it originates. • IL, IN, MO, OH, PA, TN, WV produce 50 - 75% of acid deposition that contaminates New England and southeastern Canada

49. Acid Deposition • Facilitating Recovery from Acid Deposition • Reduction of emissions of sulfur dioxide and nitrogen oxides curbs acid deposition

50. Links Among Global Climate Change, Ozone Depletion, and Acid Deposition • Evidence has surfaced of combined effects of acid deposition, ozone depletion, and climate warming – synergistic effect • Climate Warming May Hurt Ozone Recovery