ATM S 111, Global Warming: Understanding the Forecast

1. ATM S 111, Global Warming: Understanding the Forecast Dargan M. W. Frierson Department of Atmospheric Sciences Day 17: 05/25/2010

2. Undergraduate Research Symposium • UW Undergrad Research Symposium was last Friday • 686 student presenters from all around campus • Departments from Aeronautics to Women’s Studies • Poster presentations & talks • Research opportunities are available in a variety of different departments • We encourage our best students to get involved in research projects! • I supervise 3 undergrads right now

3. Good News on Malaria • We discussed how climate change may lead to the spread of tropical diseases into new locations • New study from Oxford suggests that humans are stopping the spread of malaria faster than it is advancing due to climate change • And that further attention to prevention can likely stop much of the spread of this deadly disease • Related to the last lecture: • Impacts (& specifically attributing disasters already occurring to global warming) is most frequent scientific error of activists urging quick action • Such claims should be treated with skepticism

4. Assignments • Should have read “The Predicament” and “Political Solutions” p.278-305 • Read “Technological Solutions” p.306-332 for next time • HW due Friday at 11:59 PM • Turn in extra credit essays by Monday

5. Today: Solutions • First, the bad news • How much we will have to cut emissions to make a difference • Then, the good news • What changes we can make to get this done: we can fix it! • And many of the changes we’ll need to make will be beneficial in many other ways

6. Goals for Fixing the Problem One goal: minimize temperature increase But recall that some warming is locked in even if we keep CO2 concentrations exactly at today’s levels The yellow experiments assume concentrations are held constant at year 2000 values Temperatures still increase by 0.5o C (because the ocean takes time to warm)

7. How to Prevent Higher CO2 Concentrations Higher CO2 levels mean higher temperatures eventually: how to avoid? Emissions are increasing rapidly Is flattening out emissions enough?

8. Is Stabilizing Emissions Enough? • No! Flattening out CO2 emissions still leads to large increases in CO2concentrations • Imagining blowing air into a balloon: you have to stop blowing into it to stop it from getting bigger! • (The real system is a little less extreme than this, as the ocean can take up a small amount of emissions) Emissions Concentrations Flat emissions lead to concentrations that increase…

9. How To Stabilize Concentrations Stabilization at these concentrations….  …requires these cuts in emissions 

10. Paths to CO2 stabilization VI V IV To stabilize at 450 ppm… II I …drastic & immediate emissions cuts are necessary emissions today

11. 350 ppm? • James Hansen, NASA: scientist/activist • Brilliant scientist with many honors & awards (National Academy of Sciences, AMS Rossby Medal, Time Magazine’s Most Influential People, etc.) • Not hesitant to move into the activist role (e.g., was arrested during a mountaintop removal protest) • Was muzzled by Bush administration officials, went on 60 Minutes to whistleblow about this • “If humanity wishes to preserve a planet similarto that on which civilization developed and towhich life on Earth is adapted, paleoclimateevidence and ongoing climate change suggestthat CO2 will need to be reduced from itscurrent 385 ppm to at most 350 ppm.” 350!

12. 350 ppm? • 350.org: • Worldwide climate action group started by Bill McKibben (wrote The End of Nature, first major book on global warming)

13. Path to 350 ppm CO2concentration VI V IV II To stabilize at 350 ppm… I …emissions must plummet & we probably have to take some CO2 out of the atmosphere emissions today

14. Ways to Prevent Much More Warming • We’ll discuss ways to take CO2 out of the atmosphere later • By “scrubbing” from the air chemically, or by promoting photosynthesis • Laterwe’ll also discuss geoengineeringsolutions to cool the Earth even if CO2 levels are high • By blocking out the Sun • But let’s first discuss how to emit less CO2 • The good news: it is possible!

15. Alternative Energy Sources • We already have effective ways at generating CO2-free electricity! • Renewable energy: generated from natural sources such as solar, wind, tidal, geothermal, and hydroelectric • Nuclear is not renewable, but it also doesn’t emit CO2

16. U.S. Energy Sources U.S. energy sources (2007): • Oil 40%, • Coal 23%, • Natural gas 22%, • Nuclear 8%, • Renewables:7% Oil for transportation, coal for electricity (U.S. electricity sources: coal, nuclear and renewables dominate)

17. Useful Facts about CO2 • CO2 per unit energy emitted: • Coal emits 67% more CO2 than natural gas • Coal emits 30% more CO2 than oil • Coal is a ‘dirty fuel’ • U.S. CO2 emissions by energy sources (2007): • Oil 46%, • Coal 35%, • Gas 19%, • nuclear and renewables ~0%

19. 0.6 0.4 0.2 0 US Emissions 2006 Emissions of C (Gt) C 35% 46% Emissions of C (Gt) 19% (for reference: global emission is ~10 Gt C/yr) Source EPA #430-R-08-005 (April 2008)

20. In Washington we have Hydro Power • About 7% of the U.S. electricity comes from hydropower • 67% of Washington’s electricity • Extremely expensive to build new facilities • Possible extreme environmental damage to flooded area and fish migration • Not likely to see more dams built in the U.S.

21. Stabilizing atmospheric CO2 at ~ 500ppm • In 2004, Pacala and Socolow proposed a scheme to achieve this goal • Phase 1: No further increase in emissions until 2054, with energy production still increasing rapidly. Ramping up existing technologies to do this. • Phase 2: After 2054,rapid reductionsin global emissions. Final emissions of all GHGs must level off by ~2100 to ~ 1.5 Gt/yr, or ~20% of present global emissions.

22. Past Emissions Billion of Tons of Carbon Emitted per Year 14 (380) Historical emissions 7 (320) 0 2105 1955 2005 2055 Values in parentheses are ppm of CO2

23. Billion of Tons of Carbon Emitted per Year 14 Currently projected path = “ramp” Copenhagen Pledge Stabilization Triangle Interim Goal O Historical emissions 7 Flatpath 0 2105 1955 2005 2055 The Emission Stabilization Triangle (530) (380) (470) (320) Interim 2054 goal: stabilize emissions immediately (yet increase energy by ~70% in 2054) and invest in technology to have much more energy with reduced emissions after that Pacala and Socolow (2004)

24. 21 (830) Business As Usual GtC/yr (530) (750) 14 Ramp = Delay Stabilization triangle  850 ppm (380) Historical emissions (470) 7 Flat = Act Now  500 ppm (850) (850) (320) (500) (500) 1.5 (500) 2205 2155 1955 2005 2055 2105 Values in parentheses are ppm (1 ppm = 2.1 GtC). The Stabilization Triangle: settle for double(560) or triple(840) pre-industrial CO2? Or more??? Stabilizing at 500ppm requires the global emission be 1.5 Gt/yr by 2100 Pacala and Socolow (2004)

25. Billion of Tons of Carbon Emitted per Year 14 14 GtC/y Currently projected path Seven “wedges” O Historical emissions 7 GtC/y 7 Flatpath 0 2105 1955 2005 2055 Wedges How do we meet the increase in energy demand (projected to increase by 70% by 2050 and 200+% by 2100) without increasing emissions of CO2? Pacala and Socolow (2004)

26. What is a “Wedge”? 1 Gt C/yr Total = 25 Gigatons carbon 50 years • Cumulatively, a wedge redirects the flow of 25 Gt C in its first 50 years. A “wedge” is a strategy to reduce carbon emissions that grows in 50 years from zero to 1.0 GtC/yr. Pacala and Socolow (2004)

27. The Interim Goal is Within Reach • Reasons for optimism that global emissions in 2055 need not exceed today’s emissions: • The world today has a terribly inefficient energy system. • Carbon emissions have just begun to be priced. • Most of the 2055 physical plant is not yet built Pacala and Socolow (2004)

28. Fill the Stabilization Triangle with Seven Wedges There are 15 different options for this! Each challenging but feasible Energy Efficiency Methane Management Decarbonized Electricity 14 GtC/y Stabilization Decarbonized Fuels Triangle Forests & Soils 7 GtC/y 2004 2054 Fuel Displacement by Low-Carbon Electricity

29. Wind Electricity • Effort needed by 2055 for 1 wedge: • One million 2-MW windmills displacing coal power. • Today we have about 50,000 MW (1/40 of this) Prototype of 80 m tall Nordex2.5 MW wind turbine located in Grevenbroich, Germany (Danish Wind Industry Association) R. Socolow (per. comm.)

30. Electricity numbers • 100 Watts: relatively bright incandencentlightbulb(the non-efficient kind) • 1000 Watts: average household demand (averaged over the day) • 1 MW = 1 million Watts: average wind turbine (powers 1000 households) • 1 GW = 1 billion Watts: average coal/nuclear power plant (powers 1 million households)

31. Wind Electricity • One million 2-MW windmills displacing coal power. • Would require land space the size of Germany (but land below could be used for grazing, farmland, etc)Wind energy would only have to increase by 8% per year to achieve this (and recent increases have been 30% per year) Prototype of 80 m tall Nordex2.5 MW wind turbine located in Grevenbroich, Germany (Danish Wind Industry Association) R. Socolow (per. comm.)

32. Pholtovoltaic (solar) Power Effort Needed by 2055 for one wedge: 2000 GWpeak (700 times current capacity) 2 million hectares (about the size of New Jersey): roofs can be used though Would require 14% increase per year (we’re currently increasing at 30% per year) Graphics courtesy of DOE Photovoltaics Program

33. Effort needed by 2055 for 1 wedge: 700 GW displacing coal power (tripling current capacity). Nuclear Electricity Graphic courtesy of NRC R. Socolow (per. comm.)

34. Fuel Switching Effort needed by 2055 for 1 wedge: Substitute 1400 natural gas electric plants for an equal number of coal-fired facilities Photo by J.C. Willett (U.S. Geological Survey). One wedge requires an amount of natural gas equal to that used for all purposes today

35. Carbon Capture & Storage Effort needed for 1 wedge by 2055 Implement CCS at 800 GW coal electric plants Effort needed for 1 wedge each by 2055 Implement CCS at1600 GW natural gas electric plants Graphic courtesy of Alberta Geological Survey There are currently three storage projects that each inject 1 million tons of CO2 per year – by 2055 need 3500.

36. Coal-based Synfuels with CCS* *Carbon capture and storage • Effort needed for 1 wedge by 2055 • Capture and storage of the CO2 byproduct at plants producing 30 million barrels per day of coal-based synfuels • Assumption: half of C originally in the coal is available for capture, half goes into synfuels. Graphics courtesy of DOE Office of Fossil Energy Result: Coal-based synfuels have no worse CO2 emissions than petroleum fuels, instead of doubled emissions. Need ~1000 times today’s capacity R. Socolow (per. comm.)

37. Lots of potential for increased efficiency in USexample electricity production and use

38. Efficient Use of Electricity power industry buildings Effort needed by 2055 for 1 wedge: Use best efficiency practices in all residential & commercial buildings 25% - 50% reduction in expected 2055 electricity use in commercial and residential buildings Changing all light bulbs to CFL would be 1/3 of a wedge! R. Socolow (per. comm.)

39. Efficient Generation of Electricity Effort needed by 2055 for 1 wedge: Improve the efficiency of coal power plants from 40% to 60%, and double efficiency from which we take fossil fuels from the ground. power R. Socolow (per. comm.)

40. Efficient Use of Fuel Effort needed by 2055 for 1 wedge: Decrease the number of miles driven per car: 5,000 instead of 10,000 miles per year. Effort needed by 2055 for 1more wedge: Double fuel efficiency of cars: 60 mpg instead of 30 mpg.

41. Biofuels Effort needed by 2055 for 1 wedge: 2 billion 60 mpge cars running on biofuels instead of gasoline and diesel. To produce these biofuels: 250 million hectares of high-yield (15 t/ha) crops, one sixth of world cropland. Challenge: To find ecologically responsible ways to grow biomass for power and fuel on hundreds of millions of hectares. Usina Santa Elisa mill in Sertaozinho, Brazil (http://www.nrel.gov/data/pix/searchpix.cgi?getrec=5691971&display_type=verbose&search_reverse=1_

42. Natural Sinks Eliminate tropical deforestation OR Plant new forests over an area the size of the continental U.S. OR Use conservation tillage on all cropland (1600 Mha) Conservation tillage is currently practiced on less than 10% of global cropland Photos courtesy of NREL, SUNY Stonybrook, United Nations FAO

43. Do wedge strategies get used up? • Is the second wedge easier or harder to achieve than the first? • Are the first million two-megawatt wind turbines more expensive or cheaper than the second million two-megawatt wind turbines? • The first million will be built at the more favorable sites. • But the second million will benefit from the learning acquired building the first million. • The question generalizes to almost all the wedge strategies: • Geological storage capacity for CO2, land for biomass, river valleys for hydropower, uranium ore for nuclear power, semiconductor materials for photovoltaic collectors.

44. Summary: What’s appealing about wedges? • The stabilization triangle • Does not concede doubling CO2 is inevitable • Shortens the time frame to within business horizons • The wedge • Decomposes a heroic challenge (the Stabilization Triangle) into a limited set of monumental tasks • Establishes a unit of action that permits quantitative discussion of cost, pace, risk, trade-offs, etc • The wedge strategy • Does not change the fact there are winners (alternative energies) and losers (coal and oil become more expensive sources of energy), but brings many options to the table

45. Alternative Energies • Let’s discuss some alternative energies in more detail • Wind • Solar • Nuclear • Geothermal • Then we’ll discuss a bit about biofuels and hydrogen fuel cells for transportation…

46. Wind Power

47. How is Wind Power Generated? wind blows past a turbine (like a propeller) turbine is turned --> energy power produced is proportional to (wind velocity) 3 example: average wind speed = 5 m/s case 1: range of 4 to 6 m/s average power ~ 1/2*43 + 1/2*63 = 140 units case 2: range of 1 to 9 m/s average power ~ 1/2*13 + 1/2*93 = 365 units

48. Wild Horse Wind Farm Location – 18 miles east of Ellensburg, Kittitas County; 127 miles southeast of Seattle Land area – 9,000 acres Start-up – December 2006 Turbines – 127 Power output – 229 MW at peak capacity; 642,000 MWh annual output (est.), enough to meet the total power needs of about 55,000 households 1 MW peak capacity needed for 1 WalMart storeor 250 houses

49. Winds – must be at least 9 mph, peak capacity reached at 30 mph Produce electricity ¾ of the time at Wild Horse Turbines - 351 feet tall from the ground to the tip of a vertical rotor blade; 223 tons total weight Tower foundation – buried 25 to 32 feet (depending on bedrock depth) in up to 260 cubic yards of concrete; Generators –each produces up to 1.8 MW of power

50. Capacity – peak power capability if winds are optimal (wind), river flow is optimal (hydro), coal is burning constantly, etc. Still ignoring waste heat. Wild Horse wind farm averages 33% Coal 80% Hydropower at 50% Which power source can be most easily varied to meet demand? What does this mean? Hydropower by varying sluice gates (water input to turbine) Coal plant stays fired most of the time while often some hydropower capacity is reserved for high demand periods