2. Question 1 Who are these guys??? a)Two Cornell Trustees b)Professional Engineering College Grad Students c)The Mythbusters d)David Skorton and Hunter Rawlings

3. Question 2 What does this have to do with State of the Planet ??

4. Answer….. Today’s Lecture: Infamous Climate Change Myths BUSTED! Or….. How to dazzle your climate change skeptic friends with science

5. Myth 1 There’s not enough Carbon Dioxide in the atmosphere to matter.

6. The Truth But….Size doesn’t matter! Nitrogen Oxygen Argon CO 2

7. Carbon Dioxide

8. 4.3 µm

9. Carbon Dioxide

10. 15 µm

11. Water Vapor

13. Absorbed Energy is Trapped

14. Without an Atmosphere 2. 2. Earth absorbs sunlight and Radiates it as “heat” 4. Remaining “heat” lost to space Earth receives 240 Wm -2 from sun. Earth must lose 240 Wm -2 to space. E =  T 4 240 = 5.7x10 -8 T 4 T = -18ºC = 0°F

15. With an Atmosphere 2. 2. Earth absorbs sunlight and Radiates it as “heat” 4. Remaining “heat” lost to space Earth receives 168 Wm -2 from sun. Earth also receives 222 Wm -2 from the atmosphere. E =  T 4 168 + 222 = 5.7x10 -8 T 4 T = 15ºC = 59°F

16. Doubling Carbon Dioxide 2. 2. Earth absorbs sunlight and Radiates it as “heat” Atmosphere absorbs 4 Wm -2 more radiation Changes: 1)Amount of radiation received from atmosphere 2)Temperature Can Compute:  T = 0.3  F + feedbacks 1.2°C = 0.3 x 4 Wm -2 Less loss More absorbed and returned Temperature increase Little Effect

17. Myth 2 Water vapor is a more important GHG than Carbon Dioxide

18. The Earth’s Climate System

19. Components of the System Interact CO 2 increases Earth warms Evaporation Increases Atmospheric Water Vapor Increases Positive Feedback

20. Components of the System Interact CO 2 increases Earth warms Ice Melts Less Solar Energy Reflected (more than 240 W m -2 received) Positive Feedback

21. Components of the System Interact CO 2 increases Earth warms More Evaporation More Clouds Positive Feedback Clouds Trap Terrestrial Radiation Clouds Reflect Solar Radiation Earth Cools Negative Feedback

22. Myth 3 Carbon Dioxide will be removed from the atmosphere naturally

23. Carbon Cycle 7 100 90 2 0.1

24. Climate Carbon Feedback

25. Feedbacks Drive Ice Ages Slight Orbital Changes Decrease Solar Received N.H. Cools More Ice N.H. Cools more CO 2 Declines Earth Cools

26. Why does CO 2 decline when it’s cold? Which drink is flat? a)b)

27. Myth 1 Revisited Ice Age Not an Ice Age

28. Or a Different movie Dinosaurs No Dinosaurs

29. Myth 5 You can’t get tomorrow’s weather right, you expect me to believe your prediction for 100 years from now? A.K.A. Climate models are inaccurate

30. WEATHER ≠ CLIMATE

31. Typical Climate Model

32. Scale Matters

33. Model Validation & Attribution

34. A Question Choose the best day to swim in Cayuga Lake a) Memorial Day 5/31 Air Temperature 85° b) Labor Day 9/4 Air Temperature 85°

35. Features of the Climate System  Different components have different response times More on this laterMore on this later  Internal Forcings Things like El NinoThings like El Nino

36. Myth 6 There is time to avoid negative global warming impacts

37. Current Impacts will persist for centuries Magnitude of Response

38. Myth 7 Ah…but what about Ithaca and all those other stations Michael Crichton showed us

39. Ithaca Summer Temperature +1.5°F -2.8°F

41. What are the chances? 124 years 0.8% chance for a record 1/124

42. What are the chances? 8 years (1997-2004) 8x0.008 = 6.4% Chance of a record

43. What are the chances? All 12 months 0.64 12 = 0.00000000000047%

44. Myth 8 The problem is so big, it doesn’t matter what we do

45. Wedges

46. Wedges  Increased efficiency Electric, Transportation, Heating (3 possible wedges)Electric, Transportation, Heating (3 possible wedges) 1 wedge = 60 mpg cars1 wedge = 60 mpg cars  Switch from coal to natural gas (2 possible wedges, heat and electric) 1 wedge = 1,400 large coal plant to gas1 wedge = 1,400 large coal plant to gas  Carbon capture and storage 2 possible wedges, electric and hydrogen) 1 wedge = 800 coal plants 1 wedge = 800 coal plants 1 wedge = 3500 million tons/year stored 1 wedge = 3500 million tons/year stored  Nuclear or hydrogen (2 possible wedges, electric or hydrogen) 1 wedge = doubling of reactors 1 wedge = doubling of reactors

47. Wedges  Wind or hydrogen (2 wedges electric or hydrogen) 1 wedge = area the size of Germany 2 million windmills 1 wedge = area the size of Germany 2 million windmills  Solar electricity (1 wedge) 1 wedge = NJ size area 1 wedge = NJ size area  Biofuels (1 wedge) 1 wedge = 1/6 of present cropland 1 wedge = 1/6 of present cropland  Natural sinks (1 wedge) Halt deforestation and double rate of forest planting Halt deforestation and double rate of forest planting

48. Myth 9 Adaptation will not be required if we choose to mitigate climate change