Climate Change: The Move to Action

1. Climate Change: The Move to Action(AOSS 480 // NRE 480) Special thanks to Jasper Kok for putting together information on emissions. Richard B. Rood Cell: 301-526-8572 2525 Space Research Building (North Campus) rbrood@umich.edu http://aoss.engin.umich.edu/people/rbrood Winter 2010 February 23, 2010

2. Class News • Ctools site: AOSS 480 001 W10 • On Line: 2008 Class • Reference list from course • Rood Blog Data Base • Assigned Reading (either one) • A Plan to Keep Carbon in Check • Stabilization Wedges

3. Make Up Class / Opportunity • Make up Class on March 8, Dana 1040, 5:00 – 7:30 PM, Joint with SNRE 580 • V. Ramanathan, Scripps, UC San Diego • Please consider this a regular class and make it a priority to attend. • Pencil onto calendar on April 6, Jim Hansen, time TBD.

4. Outline • Science summary • Evaluation / Validation • Assessment / IPCC • Carbon Dioxide Emissions

5. Figure TS.23

6. 1998 Climate Forcing (-2.7, -0.6) 2001 (-3.7, 0.0) Hansen et al: (1998) & (2001)

7. HERE IS YOUR BEST CHANCE AT COOLING Positive radiative forcing warms climateNegative radiative forcing cools climate ? from Joyce Penner

8. Land Use / Land Change Other Greenhouse Gases Aerosols Internal Variability Validation Consequences Feedbacks Air Quality “Abrupt” Climate Change Summary Points: Science Correlated Observations CO2 and Temperature Observed to be strongly related on long time scales (> 100 years) CO2 and Temperature not Observed to be strongly related on short time scales (< 10 years) Theory / Empirical Evidence CO2 and Water Vapor Hold Heat Near Surface Prediction Earth Will Warm Theory / Conservation Principle Mass and Energy Budgets  Concept of “Forcing” Observations CO2 is Increasing due to Burning Fossil Fuels

9. Practices in Climate Community: Assessment / IPCC • Peer Review • Assessment • IPCC Process

10. OBSERVATIONS THEORY EXPERIMENT Scientific Investigation Problem Solving Unification Integration Knowledge Generation Reduction Disciplinary

11. OBSERVATIONS THEORY EXPERIMENT Scientific Investigation Problem Solving Unification Integration Knowledge Generation Reduction Disciplinary Assessments Refereed Journals

12. Reviewers: • Anonymous • Recuses himself / herself if prejudiced • Authors Often: • Chooses amongst Editors • Recommends Reviewers • Provides names of Collaborators • Provides names of Competitors • Editors: • A volunteer from community • Approved by publisher • Professional society • Commercial publisher • Recuses hisself / herself if prejudiced Peer Review: Understanding Science Berkeley

13. Intergovernmental Panel on Climate Change (IPCC) (The assessment process) How is this information evaluated, integrated and transmitted to policymakers? Scientist-authors are nominated by governments to assess the state of the science Published in refereed literature IPCC CLIMATE REPORTS 2001 2007 What we know + uncertainty Draft documents are reviewed by experts who did NOT write the draft. // Open review as well • U.S. Climate Change Science Program • U.S. Global Change Research Program • Assessments • U.S. National Assessment Review by government officials // Final language // All agree National Academy of Sciences Study Process Draft revised

14. Note IPCC Report Process

15. A paper of interest • Daniel Farber: • Review of Climate Modeling Activities and why they should have legal standing.

16. Consider, esp., CO2 emissions • Focus on energy • Different ways to make the accounting

17. Context: Energy and Climate Change • Consumption // Population // Energy ENERGY POPULATION CLIMATE CHANGE SOCIETAL SUCCESS CONSUMPTION

18. What are the mechanisms for production and loss of CO2?

19. Current and past energy use • Current and past energy use • CO2 emissions: where do they come from? • Current sources of energy • Emissions from economic sectors • Energy consumption by end use • External costs to energy use (besides climate change)

20. Context: Growth

21. Key references and websites • Energy Information Administration (EIA) http://www.eia.doe.gov/ keeps track of (inter)national energy use and future trends. • The ‘wedge’ paper: “A plan to keep carbon in check” by Socolow and Pacala, Scientific American, 2006. (link) • This is an influential policy-oriented paper on how to reform energy sector while still achieving economic growth

22. Current and past energy use • Current and past energy use • CO2 emissions: where do they come from? • Current sources of energy • Emissions from economic sectors • Energy consumption by end use • External costs to energy use (besides climate change)

23. World Carbon Emissions • CO2 emissions arise from: • Cement production (~5 %) • Deforestation (~20 %) • Fossil fuel use (~75 %) 75%

24. CO2 source: Cement Production • Cement is produced from limestone, which is mostly calcite (CaCO3). • For production of cement: CaCO3 CaO + CO2 • Production of cement emits CO2 for two reasons: • CO2 emitted directly • Production process takes place at high temperatures only (> 1000 ºC) which requires a lot of energy. • Accounts for ~5 % of CO2 emissions worldwide

25. CO2 source: Deforestation • Massive deforestation occurred • In developed nations during Industrial Revolution (driven by need for cheap energy) • In developing (tropical) nations right now, mostly in response to demand for cropland, pastures, and wood. • When forests are cut down, CO2 is released from: • Carbon in trees, plants, etc. (conversion to wood products preserves only small fraction) • Carbon in the soil (roots, humus) • Forests absorb “excess” CO2, since elevated CO2 stimulates growth • Removal of forests removes this natural buffer against climate change

26. CO2 source: Deforestation • Deforestation is thus an important part of climate change: • It accounts for ~20 % of current CO2 emissions • It accounted for ~35 % of total CO2 emissions since preindustrial times. GtC Compare to 590 GtC in the preindustrial atmosphere

27. CO2 source: Fossil Fuel Use • Sharp increase (16-fold!) in world energy consumption over past century • Why did this occur?

28. Context: Energy and Climate Change • Consumption // Population // Energy ENERGY POPULATION CLIMATE CHANGE SOCIETAL SUCCESS CONSUMPTION

29. Energy and Economic Success The Bottomless Well: Huber and Mills (2005)

30. So why has energy consumption increased so much? • GDP/capita is considered the “societal success” • Energy use increases have been driven by growth in population and GDP/capita. Energy use = (population)*(GDP/Person) *(energy/unit GDP)

31. Energy and population • Strong population increase since pre-industrial times! http://www.j-bradford-delong.net/TCEH/1998_Draft/World_GDP/Estimating_World_GDP.html Energy use = (population)*(GDP/Person) *(energy/unit GDP)

32. World GDP/capita • Also strong growth in GDP/capita! http://www.j-bradford-delong.net/TCEH/1998_Draft/World_GDP/Estimating_World_GDP.html Energy use = (population)*(GDP/Person) *(energy/unit GDP)

33. Energy and GDP Energy use per capita and per dollar GDP in U.S. (index, 1980 = 1) • Energy/unit GDP decreases as societies become more developed  shift from manufacturing to services (root cause of Michigan’s economic trouble) • But total energy use per capita does not decrease. EIA Annual Energy Outlook, 2008 Energy use = (population)*(GDP/Person) *(energy/unit GDP)

34. So why has energy consumption increased so much? • Main drivers of rapid increase in energy consumption have been increases in population and GDP/capita • This is why climate change problem is so difficult: • We can’t affect population (possible, but politically incorrect…) • Reducing GDP to combat climate change is also not feasible • But reduction in energy per unit GDP occurs with shift to knowledge-based economy (developed world now). • Still, reduction in world energy use not realistic. • To reduce CO2 emissions, need to drastically lower CO2 emitted per unit energy, especially since we want economy to keep growing. Energy use = (population)*(GDP/Person)*(energy/unit GDP)

35. Current and past energy use • Current and past energy use • CO2 emissions: where do they come from? • Current sources of energy • Emissions from economic sectors • Energy consumption by end use • External costs to energy use (besides climate change)

36. In what forms do we consume energy? • Fossil fuels: • Coal • Oil • Natural gas • Other: • Nuclear • Hydro • Renewables (mostly biomass) • ‘Hydrogen’ Pacala and Socolow, Science, 2004

37. Current sources of energy: Fossil fuels

38. Energy sources: Coal • Emits most CO2 per unit energy of all fossil fuels • Accounts for ~29% of world CO2 emissions • Used mostly for electricity and for home heating (especially in developing nations) • Coal burning emits significant amounts of sulfur, nitrogen and particulate matter • Proven reserves are almost endless (~250 years)

39. Coal is major source of air pollution • Coal emits sulfur and smoke particulates • “Great London smog” of 1952 led to thousands of casualties. • Caused by cold inversion layer  pollutants didn’t disperse + Londoners burned large amounts of coal for heating • Demonstrated impact of pollutants and played role in passage of “Clean Air Acts” in the US and Western Europe

40. Coal use in the US • After “Great London smog” of 1952, decrease in residential coal use • Use of coal for electricity has been growing consistently because coal is cheap and abundant, and combustion technology is readily available Coal use by sector in US EIA Annual Energy Review, 2006

41. Energy sources: Oil • Emits ~75 % of coal CO2 emissions per unit energy. • Accounts for ~30 % of world CO2 emissions. • Dominates transportation (cars), but also used for home/building heating • Proven reserves are ~40 years of conventional oil. After that, another ~100 years of unconventional oil (tar sands etc.) • U.S. dependency on imported oil is a major national security concern

42. Energy sources: Natural gas • Least polluting of the fossil fuels: emits ‘only’ ~60 % of coal CO2 per unit energy • Accounted for ~16% of world CO2 emissions • Used for electricity generation and home heating (same as coal) • Proven reserves are another ~65 years

43. Trend of fossil fuel use • In ‘business-as-usual’ fossil fuels will continue to dominate world energy • Currently rapid increase of coal use, globally. International Energy Outlook, EIA, 2007

44. Reserves of fossil fuels • We won’t be running out of fossil fuels anytime soon! • ‘Unconventional’ includes oil sands, oil shale, coalbed methane, etc.. • Unconventional fossil fuels cost more energy/effort to mine Source: World Energy Assessment, 2004

45. Current sources of energy: nuclear and renewables

46. Energy sources: Nuclear • Accounts for ~6 % of world energy consumption and ~ 19 % of US electricity generation • Used only for electricity generation • No CO2 emissions from plant operating, but some from uranium mining (~10 - 20 % of coal emissions per kWh) • Concerns about nuclear waste storage and nuclear weapons proliferation • Hardly growing in most of developed world. Nuclear share of electricity generation in U.S. Nuclear power plant licenses issued in U.S. Chernobyl EIA Annual Energy Review, 2006

47. Energy sources: Renewables Renewable energy as share of total energy in U.S., 2006 • Mostly from biomass (wood), hydro power, and biofuels. • Contribution from other renewables (geothermal, solar, wind, tides) are small. EIA Annual Energy Review, 2006

48. Energy ‘sources’: Hydrogen • Hydrogen as a fuel is often misunderstood: • Hydrogen is NOT a source of energy! • It’s merely an energy carrier, much like electricity • Hydrogen is produced by electrolyzing water:  This requires electricity • Hydrogen burns cleanly • Hydrogen’s significance is that: • It can be produced using renewable energy, which would displace fossil fuel. • Emissions are easier to mitigate, because they occur at a central location rather than individual cars. • In the absence of policies including cost of climate change, hydrogen would be generated using cheap coal-generated electricity

49. Current and past energy use • Current and past energy use • CO2 emissions: where do they come from? • Current sources of energy • Emissions from economic sectors • Energy consumption by end use • External costs to energy use (besides climate change)

50. Emissions from economic sectors • Industrial: creating products from raw materials (mining, cement, agriculture) • Commercial: stores, municipalities, etc. • Transportation: cars, planes, ships US energy use by sector EIA Annual Energy Review, 2006