1. Climate Change: An Inter-disciplinary Approach to Problem Solving (CLIMATE 480 // NRE 480) Richard B. Rood Cell: 301-526-8572 2525 Space Research Building (North Campus) rbrood@umich.edu http://climate.engin.umich.edu/people/rbrood Winter 2016 March 17, 2016

2. Class Information and News Ctools site: CLIMATE_480_001_W16CLIMATE_480_001_W16 –Record of course Rood’s Class MediaWiki SiteClass MediaWiki Site –http://climateknowledge.org/classes/index.php/Climate_Change:_The_Move_to_Actionhttp://climateknowledge.org/classes/index.php/Climate_Change:_The_Move_to_Action A tumbler site to help me remember –http://openclimate.tumblr.com/http://openclimate.tumblr.com/ –http://openclimate.tumblr.com/tagged/COP-Parishttp://openclimate.tumblr.com/tagged/COP-Paris

3. Resources and Recommended Reading Socolow and Pacala, “Stabilization Wedges,” Scientific American, 2006 (link)link Other versions, additional reading –Pacala and Socolow, “Stabilization Wedges,” Science, 2004 (link)link –Socolow, “Wedges Reaffirmed,” Climate Central, 2011 (link)link –Blog at climateprogress (link)link

4. Wedges on the Web Carbon Mitigation Initiative @ Princeton UniversityCarbon Mitigation Initiative

5. Outline: Class 15, Winter 2016 Some Synthesis Mitigation Wedges Energy Futures Enormous number of background slides

6. Basic Constraints (e.g. Pielke, Jr) The need for technology to make solutions possible. Inequity of wealth, access to basic resources, desire for economic growth makes energy use an imperative Must go –From, we use too much energy, fossil fuels are cheap –To, we need more energy, fossil fuels are expensive

7. What is short-term and long-term? 25 years 50 years75 years100 years0 years ENERGY SECURITY ECONOMY CLIMATE CHANGE Pose that time scales for addressing climate change as a society are best defined by human dimensions. Length of infrastructure investment, accumulation of wealth over a lifetime,... LONG SHORT There are short-term issues important to climate change. Election time scales

9. Emissions Trajectories https://www.climateinteractive.org/tools/scoreboard/scoreboard-science-and-data/

10. Less people Smaller economy Increase efficiency Switch energy sources Population management Limit generation of wealth Do same or more with less energy Generate energy with less emissions Carbon emissions = C = P * GDP * TE * C ------ ---- ---- P GDP TE FactorLever Population GDP per person Energy intensity Carbon intensity Approach to Policy GDPTechnology P GDP/P TE/GDP C/TE What tools do we have to reduce emissions? From R. Pielke Jr. The Climate FixR. Pielke Jr. The Climate Fix

11. link

12. Mitigation Wedges “Practical” or “Possible” Response Space

13. From Lecture on International Policy “Avoid dangerous climate change” –Avoid 2°C (1.5°C) global average warming –Keep carbon dioxide ( + other greenhouse gases) to less than 450 ppm equivalent

14. World at 450 ppm CO 2 ? We get to emit a trillion tons of carbon to stay below 450 ppm CO 2

15. Trillion Tons: Carbon VisualsCarbon Visuals

16. Increase of Atmospheric Carbon Dioxide (CO 2 ) Data and more information

17. Past Emissions Princeton Carbon Mitigation Initiative

18. The Stabilization Triangle Princeton Carbon Mitigation Initiative

19. The Wedge Concept Princeton Carbon Mitigation Initiative

21. Stabilization (2006) Princeton Carbon Mitigation Initiative

22. CO 2 stabilization trajectory (2006) Stabilize at < 550 ppm. Pre-industrial: 275 ppm, current: ~400 ppm. Need 7 ‘wedges’ of prevented CO 2 emissions.

23. Princeton Carbon Mitigation Initiative (2011)

24. Where Do We Sit? Concept that we can take these actions to limit emissions. Growing population. Economic and development imperatives. Need for more energy. Technological development. Societal inertia.

26. Energy Futures

27. Energy Decarbonization Tools:1. Efficiency Gains The low-hanging fruit Essentially three kinds: –End-use electricity efficiency (fluorescent bulbs instead of incandescent bulbs, buildings / insulation) –Energy generation efficiency (coal plant operating at 60 % efficiency instead of current 40 %) –Transportation efficiency (60 mpg instead of 30 mpg) Efficiency gains are generally cheap mitigation options But will only get so far before cutting into primary energy used for economic activity

28. McKinsey 2007: Large

29. McKinsey 2007

30. Energy Decarbonization Tools: 2. Renewable energy Hydro-power –Already widely used - not much potential for expansion Wind –Abundant and competitive Solar –Photovoltaic (PV) –Concentrating solar

31. Energy Decarbonization Tools: 2a. Wind A promising renewable energy source Supplies ~1 % of world electricity, ~0.3 % in US Is cost-effective against coal and natural gas Is undergoing very rapid growth Wind energy cost in $/kWh

32. Advantages: –Wind energy is relatively mature technology and is cost effective –Can be utilized at all scales Large wind farms On small agricultural farms –Total theoretical potential of wind energy on land/near shore is 5x current energy consumption  Large potential for expansion Energy Decarbonization Tools: 2a. Wind

33. Disadvantages: –Dependent on Production Tax Credits provided by congress (~2 cents/kWh) to be competitive –Horizon pollution and NIMBY siting problems –Birds…(though this is often over-stated – about 1-2 birds per turbine per year) –Wind is intermittent. It can therefore not make up a large fraction of base load (unless effective energy storage) Energy Decarbonization Tools: 2a. Wind

34. Energy Decarbonization Tools: 2b. Solar Essentially three kinds: 1.Solar heat –Water is heated directly by sunlight –Used cost-effectively on small scale in houses 2.Solar photovoltaic (PV) –Uses photo-electric effect (Einstein!) to produce electricity –Supplies ~0.04 % of world energy use 3.Solar concentrated –Use large mirrors to focus sunlight on steam turbine or very efficient PV panels –More cost-effective than just PV

35. Energy Decarbonization Tools: 2b. Solar Advantages: –Enormous theoretical potential –Applicable at various scales (individual houses to solar plants) –Solar heating can be cost effective –Economy of scale and/or breakthroughs might reduce costs of PV and solar concentrated Disadvantages –Expense: But likely more than cost competitive by 2020. –Intermittent – can not make up large portion of base load (except with storage capability) –Covers land with solar panels

36. Energy Decarbonization Tools: 3. Carbon Capture and Sequestration (CCS) Main idea: –Burn fossil fuels for electricity/hydrogen production –Capture CO 2 –‘Sequester’ it in geological formation, oil/gas field, or ocean floor This principle is immensely important for future CO 2 mitigation –Fossil fuels are abundant and cheap –Renewable energy generally not mature enough to replace fossil fuels –Coal-fired power plants with CCS could provide low-carbon energy at competitive costs

37. CCS: Carbon Capture Both conventional and modern types of coal-fired power plants can be adapted for CCS Conventional coal-fired power plant: –Burn coal in air (much like the old days) –Exhaust gas is ~15 % CO 2 (rest is mostly nitrogen and water vapor) –Exhaust gas flows over chemicals that selectively absorb CO 2 (‘amines’) –The amines are heated to ~150 ºC to give up the CO 2 and produce a (nearly) pure CO 2 gas that can be sequestered. Modern coal-fired power plant: –Coal is burned with pure oxygen in a gasification chamber to produce hydrogen and CO 2 –The CO 2 is filtered out and the hydrogen is burned for electricity

38. CCS: Sequestration 1.Depleted oil/gas reservoirs (can even be used to enhance oil/gas recovery – reduces costs) 2.Deep saline (brine) formations – these are porous media in which CO 2 can be stored and dissolve in the salty water 3.Use for coal-bed methane recovery (one of those ‘unconventional’ fossil fuels) 4.Ocean floor (very controversial!)  CO 2 can be sequestered at ~1 km underground, here pressure is high enough to liquify CO 2, which helps prevent it from leaking  Several options for sequestering CO 2:

39. CCS: economics CCS could become cost-effective with future carbon legislation

40. Energy Decarbonization Tools: 4. Biofuels Initially hailed as a sustainable substitute for oil Can help reduce oil imports and improve national security –In US, this is probably main motivation for recent push (“addicted to oil”, Bush’s 2006 State of the Union) Two main kinds of biofuels: 1.First generation: Produced by converting sugar in corn, sugar beets, etc., into ethanol (alcohol) 2.Second generation: Produced through “cellulosic conversion” of biomass into sugar, then sugar into ethanol Climate change impact of different biofuels is very different

41. Biofuels – First Generation In US, mainly corn-based ethanol –Heavily subsidized by federal government to reduce oil dependence (~$1.90/gallon) Effect on climate change is negative: –Energy used in production is comparable to energy content –Significant amounts of N 2 O (a potent GHG) can be produced through fertilizer use –Often, more carbon would be sequestered by letting crop land lie fallow –Raises food prices  Tropical deforestation, which releases more carbon than saved from fuel production over > 30-year period Source: Fargione et al., Science, 2008

42. Biofuels – Second Generation Produced from plants containing cellulose –Cellulosic conversion to sugar is very difficult and expensive (cows have 4 stomach compartments for a reason…) Second generation biofuels are better for climate change: –Similar amount of carbon sequestered as fallow cropland –But, competition with food could still lead to tropical deforestation and net release of carbon US 1 st generation biofuel US 2 nd generation biofuel

43. Biofuels – do they help or hurt? In general, biofuels that compete with food will not contribute to mitigating climate change –Direct link between food demand/prices and tropical deforestation Production of first generation biofuels (directly from food such as corn) is not a solution to climate change and should be avoided! Production of second generation biofuels (from biomass) is only helpful if it doesn’t compete with food production (so not grown on cropland) –Second generation biofuels from marginal farmland or agricultural waste could play important role, but is currently not cost-effective –Could play an important role in mitigating transportation emissions if breakthroughs in cellulosic conversion are made

44. Water Energy Intersection Both energy and water are critical resources Many areas already suffer water stress –note Africa, India, China, where greatest population growth is projected to occur Projected to become worse with increasing population, pollution, and climate change –Dry areas are generally projected to become drier. Must address energy challenge without exacerbating water scarcity

45. Some Biofuel References Searchinger, Ethanol and Greenhouse gases, 2008Searchinger, Ethanol and Greenhouse gases, 2008 Tilman, Biofuels and Food and Energy and Environment, 2009Tilman, Biofuels and Food and Energy and Environment, 2009 Fargione, Biofuels and Land Use, 2008 Royal Society, Biofuels, 2008 DOE, Energy and Water Use, 2006

50. Energy Summary (1) Energy is far more important to policy makers than climate change –Energy Security –Existing versus Potential Futures Interface of Climate, Economics and Policy –Standard of living –Employment

51. Energy Summary (2) Energy is highly controversial amongst climate scientists worried about mitigation –Role of nuclear energy Jim Hansen and nuclear energy Rocky Mountain Institute Union of Concerned Scientists Nathan Lewis Summary –Coal with sequestration –Nuclear with breeder reactors –Solar with technology development

52. Summary: Class 15, Winter 2016 Mitigation: Limiting the warming is possible. –Behavior and practice –Technology and economics –Personal-scale action matter Energy systems –Transition to cleaner energy in developed world –Growth of energy production and consumption in developing world is dominated by fossil fuels –Efficiency remains the easiest and most cost effective way to make a difference

53. Outline: Class 15, Winter 2016 Some Synthesis Mitigation Wedges Energy Futures Enormous number of background slides

54. Slides to Support Analysis

55. Energy Figures from Mark Barteau

56. http://news.cnet.com/8301-11128_3-20006361-54.html Land requirements for different energy sources

57. International Energy Agency, World Energy Outlook 2012

63. Water Scarcity etc. from Nancy Love

64. http://www.un.org/waterforlifedecade/scarcity.shtml The world will experience increased water stress and scarcity. Projections are particularly dire in low or emerging economies and the Western US. By 2025, 2/3 of the world population will be under conditions of water stress.

65. http://www.zaragoza.es/ciudad/medioambiente/onu/en/detallePer_Onu?id=71 Water stress refers to the availability of water

66. http://www.zaragoza.es/ciudad/medioambiente/onu/en/detallePer_Onu?id=71 Water scarcity refers to water availability AND water access

67. http://www.unep.org/dewa/vitalwater/article155.html

68. http://www.unep.org/dewa/vitalwater/article28.html

70. Climate Analysis: Rood

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

72. 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

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

74. 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.

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

76. Radiation Balance Figure

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

78. Hansen et al: (1998) & (2001) (-2.7, -0.6) (-3.7, 0.0) 1998 2001 Climate Forcing