1. Climate Change: The Move to Action (AOSS 480 // NRE 480) Richard B. Rood Cell: 301-526-8572 2525 Space Research Building (North Campus) rbrood@umich.edu http://aoss.engin.umich.edu/people/rbrood Winter 2014 January 28, 2014

2. Class News Ctools site: AOSS_SNRE_480_001_W14AOSS_SNRE_480_001_W14 News / New Book –MacKenzie Funk, who took this class on 2012, published the book Windfall: The Booming Business of Global Warming. Good interview on Fresh Air 20140128. In Windfall: The Booming Business of Global Warming, journalist McKenzie Funk looks into how some entrepreneurs and even some nations stand to benefit from a changing climate.Windfall: The Booming Business of Global Warming Fresh Air 20140128 Politics of Dismissal Entry Model Uncertainty Description

3. This lecture: Projects Back to the past –Why is the past important? –How do we investigate the past? –Observation and model-based science –Radiative balance of the Earth Things that absorb energy Things that reflect energy

4. Course Project Reflective of workplace … –“Complex Problems with no Known Solutions.” Groups of individuals with varied expertise Responsive to “news” –Relationship of news to science Project will provide recommendations, a strategy for addressing the complex problem. –What are first steps? –What do we need to look out for as these steps are taken? Monitor progress // briefing during the course Presentation at end of course Ideally: –Imagine that I am the proverbial decision maker and I have a problem –You provide me with a set or a portfolio of knowledge-based scenarios weighing different decisions –Usually, some sort of analysis and position paper

5. Use of climate information Research on the use of climate knowledge states that for successful projects, for example: –Co-development / Co-generation –Trust –Narratives –Scale Spatial Temporal Lemos and Morehouse, 2005

6. Projects Broad subjects and teams defined Meeting 1 with Rood –Now to early March: Project vision and goals Meeting 2 with Rood –Mid to late March: Progress report, refinement of goals if needed Class review –Short, informal presentation, external review and possible coordination Oral Presentation: April 10 and 12 Final written report: April 25

7. Scientific Method and Earth’s Climate We will first break the scientific investigation down into pieces. –Theory … Draw a Picture –Observations –Prediction –Attribution –Impacts We will look at the links of climate change to the other parts of the problem. –There is not a simple “solution;” we will not solve this problem and walk away from it. –We will be required to manage the climate We will define ways forward.

8. Potential Projects Emissions from agriculture Communications –Alaska and climate change Heat and cold and human health Fracking: What does it really mean for climate change? Evaluation of adaptation tools

9. This lecture: Back to the past –Why is the past important? –How do we investigate the past? –Observation and model-based science –Radiative balance of the Earth Things that absorb energy Things that reflect energy

10. Temperature and Carbon Dioxide (CO2): The last 350,000 years 350,000 years of Surface Temperature and Carbon Dioxide (CO 2 ) at Vostok, Antarctica, from bubbles of air trapped in ice cores  During this period, temperature and CO 2 are closely related to each other  Times of low temperature have glaciers, ice ages (CO 2 <~ 200 ppm)  Times of high temperature associated with CO 2 of < 300 ppm This has been extended back to > 700,000 years

11. From the Ice Core Data: Questions? We see a relationship between carbon dioxide (CO 2 ) and Temperature (T) –What is the cause and effect? –Why do we bounce between these two regimes? –Dynamic equilibrium? Are these oscillations forced in some way by an external force? –Are there other parameters or attributes which are correlated with this behavior? What is different from the stock market, where “past behavior does not indicate future performance?”

12. Thinking about these figures and ice ages Correlations Cause and effect Scientific method

13. Let’s Look at the past 1000 years We have more sources of observations. We have better observations. We have public records and literature and natural history.

14. Let’s look at just the last 1000 years Surface temperature and CO 2 data from the past 1000 years. Temperature is a northern hemisphere average. Temperature from several types of measurements are consistent in temporal behavior.  Medieval warm period  “Little ice age”  Temperature starts to follow CO 2 as CO 2 increases beyond approximately 300 ppm, the value seen in the previous graph as the upper range of variability in the past 350,000 years.

15. Let’s look at just the last 1000 years Surface temperature and CO 2 data from the past 1000 years. Temperature is a northern hemisphere average. Temperature from several types of measurements are consistent in temporal behavior. Note that on this scale, with more time resolution, that the fluctuations in temperature and the fluctuations in CO 2 do not match as obviously as in the long, 350,000 year, record. What is the cause of the temperature variability? Can we identify mechanisms, cause and effect? How? {

16. What do we see from the past 1000 years On shorter time scales the CO 2 and T are not as cleanly related. Periods on noted warmth and coolness are separated by changes in average temperature of only 0.5 F. Changes of average temperature on this scale seem to matter to people. –Regional changes, extremes? Recent changes in both T and CO 2 are unprecedented in the past several hundred thousands of years. –And the last 10,000 years, which is when humans have thrived in the way that we have thrived.

17. Why do we need to understand these bumps and wiggles?

18. How do we investigate these bumps and wiggles?

19. Conservation (continuity) principle M today = M yesterday + I - E Let’s get some money and buy stuff. Income Expense Energy from the Sun Energy emitted by Earth (proportional to T) Earth at a certain temperature, T

20. Balancing the Budget Today’s Money = Yesterday’s Money + Money I Get – Money I Spend Today’s CO 2 = Yesterday’s CO 2 + CO 2 I Get – CO 2 I Spend Today’s Energy = Yesterday’s Energy + Energy I Get – Energy I Spend

21. Some jargon, language Income is “production” is “source” Expense is “loss” is “sink” Exchange, transfer, transport all suggest that our “stuff” is moving around.

22. Point of View

23. Focus attention on the surface of the Earth

24. Simple earth 1

25. What do we do? We develop models based on the conservation of energy and mass and momentum, the fundamental ideas of classical physics. (Budget equations) We break things into pieces, deconstruct, reduce We determine the characteristics of production and loss energy (heat) from theory and observations of, for instance, the eruption of a major volcano and the temperature response as measured by the global observing system.

26. What changes energy at surface of the Earth? Natural Sun –Solar cycle Volcanoes –CO2 –Sulfuric acid droplets (aerosols) Greenhouse gases –Water, CO2 (biogeochemistry) Aerosols –Smoke –Dust –Water clouds Human or Anthropogenic Greenhouse gases Deforestation –Changes CO2 Emits Eliminates sink –Changes albedo (changes the color earth) Pollution (LA)

27. Let’s look at just the last 1000 years Surface temperature and CO 2 data from the past 1000 years. Temperature is a northern hemisphere average. Temperature from several types of measurements are consistent in temporal behavior.

28. Schematic of a model experiment.   Start model prediction Model prediction without forcing Model prediction with forcing Model prediction with forcing and source of internal variability Observations or “truth” E a t+  t = E a t +  t ( (P a – L a E a ) + (Tr a  oil + M a ) )

29. Studies like this are important Abrupt onset of the Little Ice Age triggered by volcanism and sustained by sea- ice/ocean feedbacks –Miller et al. 2012, Geophysical Research Letters Link from Journal PDF from NCAR Some commentary

30. Let’s focus on the balance of the energy at the Earth’s surface

31. Let’s build up this picture Follow the energy through the Earth’s climate. As we go into the climate we will see that energy is transferred around. –From out in space we could reduce it to just some effective temperature, but on Earth we have to worry about transfer of energy between thermal energy and motion of wind and water.

32. But the Earth’s surface temperature is observed to be, on average, about 15 C (~59 F). The sun-earth system (What is the balance at the surface of Earth?) SUN Earth Based on conservation of energy: If the Earth did NOT have an atmosphere, then, the temperature at the surface of the Earth would be about -18 C ( ~ 0 F). Welcome Back Radiative Balance. This is conservation of energy, which is present in electromagnetic radiation.

33. Building the Radiative Balance What happens to the energy coming from the Sun? Energy is coming from the sun. Two things can happen at the surface. In can be: Reflected Top of Atmosphere / Edge of Space Or Absorbed

34. Building the Radiative Balance What happens to the energy coming from the Sun? We also have the atmosphere. Like the surface, the atmosphere can: Top of Atmosphere / Edge of Space Reflect or Absorb

35. Building the Radiative Balance What happens to the energy coming from the Sun? In the atmosphere, there are clouds which : Top of Atmosphere / Edge of Space Reflect a lot Absorb some

36. Building the Radiative Balance What happens to the energy coming from the Sun? For convenience “hide” the sunbeam and reflected solar over in “RS” Top of Atmosphere / Edge of Space RS

37. Building the Radiative Balance What happens to the energy coming from the Sun? Consider only the energy that has been absorbed. What happens to it? Top of Atmosphere / Edge of Space RS

38. Building the Radiative Balance Conversion to terrestrial thermal energy. 1) It is converted from solar radiative energy to terrestrial thermal energy. (Like a transfer between accounts) Top of Atmosphere / Edge of Space RS

39. Building the Radiative Balance Redistribution by atmosphere, ocean, etc. 2) It is redistributed by the atmosphere, ocean, land, ice, life. (Another transfer between accounts) Top of Atmosphere / Edge of Space RS

40. Building the Radiative Balance Terrestrial energy is converted/partitioned into three sorts SURFACE 3) Terrestrial energy ends up in three reservoirs (Yet another transfer ) Top of Atmosphere / Edge of Space ATMOSPHERE CLOUD RS WARM AIR (THERMALS) PHASE TRANSITION OF WATER (LATENT HEAT) RADIATIVE ENERGY (infrared) It takes heat to Turn ice to water And water to “steam;” that is, vapor

41. Building the Radiative Balance Which is transmitted from surface to atmosphere SURFACE 3) Terrestrial energy ends up in three reservoirs Top of Atmosphere / Edge of Space ATMOSPHERE CLOUD RS (THERMALS)(LATENT HEAT) (infrared) CLOUD

42. Building the Radiative Balance And then the infrared radiation gets complicated SURFACE Top of Atmosphere / Edge of Space ATMOSPHERE CLOUD RS (THERMALS)(LATENT HEAT) (infrared) CLOUD 1) Some goes straight to space 2) Some is absorbed by atmosphere and re-emitted downwards 3) Some is absorbed by clouds and re-emitted downwards 4) Some is absorbed by clouds and atmosphere and re-emitted upwards

43. Want to consider one more detail What happens if I make the blanket thicker?

44. Thinking about the greenhouse A thought experiment of a simple system. SURFACE Top of Atmosphere / Edge of Space ATMOSPHERE (infrared) 1)Let’s think JUST about the infrared radiation Forget about clouds for a while 2) More energy is held down here because of the atmosphere It is “warmer” 3) Less energy is up here because it is being held near the surface. It is “cooler”

45. Thinking about the greenhouse A thought experiment of a simple system. SURFACE Top of Atmosphere / Edge of Space ATMOSPHERE (infrared) T effective 1)Remember we had this old idea of a temperature the Earth would have with no atmosphere. This was ~0 F. Call it the effective temperature. Let’s imagine this at some atmospheric height. 2) Down here it is warmer than T effective T > T effective 3) Up here it is cooler than T effective T < T effective

46. Thinking about the greenhouse Why does it get cooler up high? SURFACE Top of Atmosphere / Edge of Space ATMOSPHERE (infrared) 1) If we add more atmosphere, make it thicker, then 2) The part coming down gets a little larger. It gets warmer still. 3) The part going to space gets a little smaller It gets cooler still. The real problem is complicated by clouds, ozone, ….

47. So what matters? Things that change reflection Things that change absorption Changes in the sun If something can transport energy DOWN from the surface. THIS IS WHAT WE ARE DOING

48. Radiation Balance Figure

49. Radiative Balance (Trenberth et al. 2009)Trenberth et al. 2009

50. This lecture: Projects Back to the past –Why is the past important? –How do we investigate the past? –Observation and model-based science –Radiative balance of the Earth Things that absorb energy Things that reflect energy

51. Iconic and Fundamental Figures

52. Scientific investigation of Earth’s climate SUN: ENERGY, HEATEARTH: ABSORBS ENERGY EARTH: EMITS ENERGY TO SPACE  BALANCE

53. Sun-Earth System in Balance The addition to the blanket is CO 2 SUNEARTH EARTH: EMITS ENERGY TO SPACE  BALANCE PLACE AN INSULATING BLANKET AROUND EARTH FOCUS ON WHAT IS HAPPENING AT THE SURFACE

54. Increase of Atmospheric Carbon Dioxide (CO 2 ) Data and more information Primary increase comes from burning fossil fuels – coal, oil, natural gas

55. Temperature and CO 2 : The last 1000 years Surface temperature and CO 2 data from the past 1000 years. Temperature is a northern hemisphere average. Temperature from several types of measurements are consistent in temporal behavior.  Medieval warm period  “Little ice age”  Temperature starts to follow CO 2 as CO 2 increases beyond approximately 300 ppm, the value seen in the previous graph as the upper range of variability in the past 350,000 years.

56. CLOUD-WORLD The Earth System ATMOSPHERE LAND OCEAN ICE (cryosphere) SUN

57. Radiation Balance Figure

58. Radiative Balance (Trenberth et al. 2009)Trenberth et al. 2009