The document discusses the composition and layers of Earth's atmosphere from space-based observations. It notes that early astronauts were struck by the atmosphere's thin, fragile appearance from orbit and how it forms a habitable barrier around the planet. The document also outlines the evolution of the atmosphere over geological time and factors like oxygen levels, and examines current issues like air pollution and the greenhouse effect.

2. “ We live in an ocean of the element, air.” - Torricelli Earth from space, Apollo 13 Air and Atmosphere

3. Earth-rise over moon “It was so ironic, after spending all that money to get to the moon, the most impressive sight was our own Earth in the vast blackness of space. It was the only color we could see in the universe and was a gorgeous, moving sight.” -Edward Anders, Apollo 8, 1968 Moon is dead - it has no atmosphere.

4. Earth’s atmosphere seen from Earth orbit “For the first time in my life I saw the horizon as a curved line. It was accentuated by a thin seam of dark blue light- our atmosphere. Obviously this was not the ocean of air I had been told so many times in my life. I was terrified by its fragile appearance. - Ulf Merbold, West German astronaut on Columbia, 1983

6. Air composition table

7. A graph of temperature altitude vs. temperature shows that the Earth’s atmosphere has four definite layers (with three boundary lines = . . pauses)

8. Altitude vs. temp

9. Layers of the Atmosphere & their uses

10. Altitude vs. T and altitude vs. P

11. Atmosphere as concentric spheres around the earth

13. Smog p.113

14. London smog, 1952 Sulfur dioxide

15. Mexico city brown photochemical smog Normal conditions: Warm air rises “ Temperature inversion” Warmer air above prevents the cooler, dirtier air from rising. This keeps air pollutants from rising or escaping.

16. China has 16 of the 20 most polluted cities in the world, due to overpopulation and coal burning. This is Zunyi.

17. Atmospheres of Stars & Planets

18. Harold Urey’s Hypothesis: All new planets should have an atmosphere of methane, ammonia, water, and hydrogen (H 2 )

19. Chemical Evolution of the Planetary Atmospheres

20. Follow-up to Urey’s Hypothesis: The Miller-Urey Experiment

21. Stanley Miller with Tesla coil to supply spark to methane, ammonia, water, and hydrogen. Experiment performed at University of Chicago, 1953 Result of this experiment: He detected amino acids (up to 15) of the twenty found in life, “the building blocks of proteins”.

22. Red beds and BIF (Banded Iron Formations) contain minerals that would react with present level of oxygen. That is evidence that they were deposited when the atmosphere contained much less oxygen than the present concentration.

23. Graph of the History of the Earth’s Atmosphere Evolution of fermentation, photosynthesis, and respiration 1 2

24. Berkner-Marshall Model 1 -> 1 2 2 -> Cambrian explosion Life emerges from ocean Origin of life 2 1

25.  Years Before Present (in millions of years) PAL 1 2 1 2 “ Middle life” Era “ Recent Life” Era “ Early Life” Era

26. Sun

27. Sun and Coronal Holes Seen by UV

28. The sun sends a full range of electromagnetic radiation (from gamma & X-rays to radio waves) which hits the Earth

29. Chlorofluorocarbons (CFCs, Freons®) and related compounds

30. CFCs: Too good to be true

31. Industrial and formerly home-refrigeration systems In 1930s, these were kept on the back porch; too dangerous to have inside any house.

32. Chapman cycle

33. CFC Problem

34. Table of CFCs, HCFCs, etc. CFCs and some possible replacements

35. CFC, HCFC, HFC use in Sweden

36. Energy distribution of EM radiation from sun Absorption by ozone

37. Three forms of oxygen in our atmosphere Name Formula Structure Oxygen atom O O Oxygen molecule O 2 O = O Ozone molecule O 3

38. Temperature plot vs. altitude of the atmosphere shows the location of the ozone layer Tropospheric ozone is at the lowest 3 km.

39. Ozone remover: good buy? Or goodbye?

40. Carbon dioxide & Future Climate

41. Carbon dioxide concentration (in parts per million) measured at Mauna Loa, Big Island, Hawaii

42. “ Keeling graph” 1958 to 2010 The increase in concentration of carbon dioxide as measured at Mauna Loa Observatory, Hawaii (as of 2010). Plotted here as monthly average values so the graph shows the annual variation of growing seasons (Summer) and seasons with less plant growth (Winter).

43. Keeling graph, 1958 – 2009

44. Ice Core from Antarctic drilling

45. Bubbles in Antarctic ice

46. Greenhouse effect explained

47. Greenhouse (Hothouse) flowers A Greenhouse lets in light and heat and the glass deters convection, so the greenhouse becomes hot. The atmospheric greenhouse effect is different.

48. Graph of global temperature with years

49. Temp. increase has followed carbon dioxide increase

50. The Greenhouse Gases

51. Greenhouse effect -> Global warming

52. The moon’s average distance from the sun is the same as the Earth’s. The average temperature on the Moon is below the freezing point of water. If the Earth had no atmosphere and no greenhouse effect, the Earth would be as cold as the moon.

53. Mercury Mercury has no atmosphere, so ancient craters are not much weathered, similar to the moon. Most non-experts would have a difficult time distinguishing between pictures of the moon and pictures of Mercury.

54. The terrestrial planets and their surfaces

55. Melting of Arctic ice

56. Greenland ice, 1992, 2002, & 2005

57. Predicted temp. increase

58. Coastal flooding predicted from global warming

59. Lands that will be flooded plus many island countries will be under water

60. Stronger more powerful storms predicted as global warming makes more humidity to drive hurricanes and tornados.

61. Hurricane Katrina Jan. 22, 2007

62. Agreement & Disagreement (skeptics)

63. Four environmental problems Read this table carefully as it is commonly used to make exam questions .

64. Greek & Latin roots for air on Blackboard under “ Course Documents”