Modeling Post-2012 Climate Policy Scenarios

Modeling Post-2012 Climate Policy Scenarios Interim Results Elliot Diringer, Director of International Strategies Pew Center on Global Climate Change Leon Clarke, Kate Calvin, Marshall Wise, Jae Edmonds Joint Global Change Research Institute, Pacific Northwest National Laboratory/Battelle Memorial Institute

Objectives To visualize alternative forms of a multi-track climate framework integrating different types of mitigation commitments To assess their: Environmental effectiveness: Produce near/mediumterm effort consistent with 450-600 ppmv CO 2? Economic efficiency: Relative to a idealized case of full global cap+trade Fairness: Achieve a reasonable distribution of costs? Scenarios are illustrative not proposals Real value is in insights, not numbers

The Model O bj ECTS-MiniCAM Model developed and run by Joint Global Change Research Institute, Battelle/UMD Partial equilibrium; Energy-Agriculture-Economy Explicit energy technologies, regional specifications End-use sectors: buildings, industry, transportation Supply sectors: fossil-fuels, biomass (traditional and modern), electricity, hydrogen, synthetic fuels Integrated agriculture and land use model CO 2 only 13 Regions Runs from 1990 to 2095 in 15-year time steps

Overview of MiniCAM

Regions in the Model The regions: Australia/New Zealand Canada Europe Former Soviet Union Japan United States Africa China India Latin America Middle East South Korea (Rest of) South & East Asia

Developing the Scenarios Policies in scenarios reflect: What countries already doing (or discussing) Specific domestic policies, specific sectors targeted The world of commitment types Being discussed in the UNFCCC and beyond Action/Commitment Types: Targets Economy wide targets Policy-based commitments National-level sectoral targets, efficiency standards International sectoral agreements Sector-specific targets or standards applied across regions Funds for adaptation and technology

Differentiation within Scenarios Regional differentiation taking into account: Regional emissions contexts Fuel mix Energy and GHG intensity and efficiency Economic indicators GDP, GDP/capita Mitigation costs, cost as share of GDP Emissions projections Reference case Efficient 450, 550, 650 ppmv stabilization scenarios Differentiation is illustrative, not formulaic

Emissions Trading Mix of approaches: Full trading (initially or over time) Policy crediting Intra-sectoral trading Different combinations of the above

Overview of Scenarios Baseline scenarios Reference case: business as usual pathway Based on CCSP MiniCAM Scenario (updated for 2008) Efficient stabilization pathways to 450, 550, & 650 ppmv CO 2 Six policy scenarios 1A 550: Targets + limited policy commitments 1A 450: Targets + limited policy commitments 1B 450: Targets + broader policy commitments 2 450: Targets + sectoral agreements 3 550: Targets + policy commitments + sectoral agreements 3 450: Targets + policy commitments + sectoral agreements It is assumed that world moves to a global trading regime after 2050, however The focus here is on the near-term A theme of this research is that eventually there needs to be a move to broad coverage.

Scenario 1: Targets + Policies Developed Regions Absolute economy-wide targets Policy crediting Full emissions trading Developing Regions Policy-Based Commitments Absolute economy-wide targets 2005 2050

Scenario 1A 550: Targets and Policies I Australia/New Zealand, Canada, Europe, Former Soviet Union, Japan, United States Electricity Transportation Industry Buildings Economy-Wide Carbon Constraint CO2 emissions relative to 2005 (85%, 73%, 60%) Africa China India Korea Latin America Middle East Southeast Asia Africa, China, India, Korea, Latin America, Middle East, Southeast Asia Power Sector Carbon Intensity Relative to 2005 (NA, 70%, 50%) Power Sector Carbon Intensity Relative to 2005 (70%, 50%, 35%) Power Sector Carbon Intensity Relative to 2005 (70%, 50%, 35%) Power Sector Carbon Intensity Relative to 2005 (70%, 50%, 35%) Power Sector Carbon Intensity Relative to 2005 (NA, 70%, 50%) Power Sector Carbon Intensity Relative to 2005 (70%, 50%, 35%) Power Sector Carbon Intensity Relative to 2005 (70%, 50%, 35%) (5%, 7.5%, 10%) (20%, 45%, 75%) (NA, 5%, 7.5%) (NA, 20%, 45%) (5%, 7.5%, 10%) (20%, 45%, 75%) (5%, 7.5%, 10%) (20%, 45%, 75%) (20%, 45%, 75%) (NA, 5%, 7.5%) (NA, 20%, 45%) Crediting % of emissions reductions sold to developed world (50%, 25%, 0%) Industry Carbon Constraint Reduction from BAU (NA, 50%, 80%) Industry Carbon Constraint Reduction from BAU (30%, 50%, 80%)

Scenario 1A 450: Targets and Policies I Australia/New Zealand, Canada, Europe, Former Soviet Union, Japan, United States Electricity Transportation Industry Buildings Economy-Wide Carbon Constraint CO2 emissions relative to 2005 (80%, 50%) Africa China India Korea Latin America Middle East Southeast Asia Africa, China, India, Korea, Latin America, Middle East, Southeast Asia Power Sector Carbon Intensity Relative to 2005 (NA, 70%) Power Sector Carbon Intensity Relative to 2005 (70%, 33%) Power Sector Carbon Intensity Relative to 2005 (70%, 33%) Power Sector Carbon Intensity Relative to 2005 (70%, 33%) Power Sector Carbon Intensity Relative to 2005 (NA, 70%) Power Sector Carbon Intensity Relative to 2005 (70%, 33%) Power Sector Carbon Intensity Relative to 2005 (70%, 33%) (5%, 11%) (20%, 68%) (NA, 5%) (NA, 20%) (5%, 11%) (20%, 68%) (5%, 11%) (20%, 68%) (20%, 68%) (NA, 5%) (NA, 20%) Crediting % of emissions reductions sold to developed world (50%, 25%) Industry Carbon Constraint Reduction from BAU (NA, 30%) Industry Carbon Constraint Reduction from BAU (30%, 67%)

Scenario 1B 450: Targets and Policies II Australia/New Zealand, Canada, Europe, Former Soviet Union, Japan, United States Electricity Transportation Industry Buildings Economy-Wide Carbon Constraint CO2 emissions relative to 2005 (80%, 50%, 20%) Africa China India Korea Latin America Middle East Southeast Asia Africa, China, India, Korea, Latin America, Middle East, Southeast Asia Power Sector Carbon Intensity Relative to 2005 (NA, 70%, 25%) Power Sector Carbon Intensity Relative to 2005 (70%, 50%, 18%) Power Sector Carbon Intensity Relative to 2005 (70%, 50%, 18%) Power Sector Carbon Intensity Relative to 2005 (70%, 50%, 18%) Power Sector Carbon Intensity Relative to 2005 (NA, 70%, 25%) Power Sector Carbon Intensity Relative to 2005 (70%, 50%, 18%) Power Sector Carbon Intensity Relative to 2005 (70%, 50%, 18%) (NA, NA, 10%) (NA, NA, 40%) (5%, 7.5%, 20%) (20%, 45%, 150%) (NA, 5%, 15%) (NA, 20%, 90%) (5%, 7.5%, 20%) (20%, 45%, 150%) (5%, 7.5%, 20%) (20%, 45%, 150%) (20%, 45%, 150%) (NA, 5%, 15%) (NA, 20%, 90%) Crediting % of emissions reductions sold to developed world (50%, 25%, 0%) Industry Carbon Constraint Reduction from BAU (NA, NA, 65%) Industry Carbon Constraint Reduction from BAU (NA, 30%, 75%) Industry Carbon Constraint Reduction from BAU (NA, 30%, 75%) Industry Carbon Constraint Reduction from BAU (30%, 50%, 90%) Industry Carbon Constraint Reduction from BAU (NA, 30%, 75%) Industry Carbon Constraint Reduction from BAU (NA, 30%, 75%) Industry Carbon Constraint Reduction from BAU (NA, 30%, 75%) Building Energy Efficiency Constraint Increase over 2005 (NA, 20%, 80%) Building Energy Efficiency Constraint Increase over 2005 (NA, NA, 80%) Building Energy Efficiency Constraint Increase over 2005 (20%, 40%, 100%) Building Energy Efficiency Constraint Increase over 2005 (NA, 20%, 80%) Building Energy Efficiency Constraint Increase over 2005 (NA, 20%, 80%) Building Energy Efficiency Constraint Increase over 2005 (NA, 20%, 80%)

Scenario 2: Targets and Sectoral Agreements Developed Regions Absolute economy-wide targets Sectoral agreements Funding commitments Emissions trading within sectors, across regions Full emissions trading Developing Regions Policy-Based Commitments 2050 Absolute economy-wide targets

Scenario 2 450: Targets and Sectoral Agreements Australia/New Zealand, Canada, Europe, Former Soviet Union, Japan, United States Electricity Transportation Industry Buildings Economy-Wide Carbon Constraint CO2 emissions relative to 2005 (80%, 50%, 20%) Africa China India Korea Latin America Middle East Southeast Asia CCS Subsidy Percent of incremental cost (100%, 75%, 50%) Low Carbon Portfolio Standard Percent of electricity (35%, 50%, 90%) (5%, 7.5%, 25%) (20%, 45%, 188%) Industry Carbon Constraint Reduction from BAU (NA, 30%, 80%) Building Energy Efficiency Constraint Increase over 2005 (20%, 40%, 125%) ADAPTATION FUND Fund United States, Canada, Europe, Japan, Australia/New Zealand, Former Soviet Union Contribute annually 0.25% value of emission allowances *Will be modeled in Phase II

Scenario 3: Targets + Policies + Sectoral Developed Regions Absolute economy-wide targets Sectoral agreements Funding commitments Emissions trading within sector, across regions Full emissions trading Developing Regions Sectoral agreements Policy-Based Commitments Economy-wide absolute targets 2005 2050

Scenario 3 550: Targets + Policies + Sectoral Australia/New Zealand, Canada, Europe, Former Soviet Union, Japan, United States Electricity Transportation Industry Buildings Economy-Wide Carbon Constraint CO2 emissions relative to 2005 (85%, 73%, 60%) Africa China India Korea Latin America Middle East Southeast Asia Adaptation Fund Power Sector Carbon Intensity Relative to 2005 (70%, 50%, 35%) United States, Canada, Europe, Japan, Australia/New Zealand, Former Soviet Union (NA, NA, 5%) (NA, NA, 20%) (5%, 7.5%, 10%) (20%, 45%, 75%) (NA, 5%, 7.5%) (NA, 20%, 45%) (5%, 7.5%, 10%) (20%, 45%, 75%) (5%, 7.5%, 10%) (20%, 45%, 75%) (20%, 45%, 75%) (NA, 5%, 7.5%) (NA, 20%, 45%) Fund Industry Carbon Constraint Reduction from BAU (NA, 30%, 50%) Contribute annually 0.25% value of emission allowances Building Energy Efficiency Constraint Increase over 2005 (NA, 20%, 40%) Building Energy Efficiency Constraint Increase over 2005 (NA, NA, 20%) Building Energy Efficiency Constraint Increase over 2005 (20%, 40%, 50%) Building Energy Efficiency Constraint Increase over 2005 (NA, 20%, 40%) Building Energy Efficiency Constraint Increase over 2005 (NA, 20%, 40%) Building Energy Efficiency Constraint Increase over 2005 (NA, 20%, 40%)

Scenario 3 450: Targets + Policies + Sectoral Australia/New Zealand, Canada, Europe, Former Soviet Union, Japan, United States Electricity Transportation Industry Buildings Economy-Wide Carbon Constraint CO2 emissions relative to 2005 (80%, 50%, 20%) Africa China India Korea Latin America Middle East Southeast Asia Adaptation Fund Power Sector Carbon Intensity Relative to 2005 (70%, 45%, 16%) United States, Canada, Europe, Japan, Australia/New Zealand, Former Soviet Union (NA, NA, 11%) (NA, NA, 45%) (5%, 7.5%, 23%) (20%, 50%, 169%) (NA, 5%, 17%) (NA, 20%, 101%) (5%, 7.5%, 23%) (20%, 50%, 169%) (5%, 7.5%, 23%) (20%, 50%, 169%) (20%, 50%, 169%) (NA, 5%, 17%) (NA, 20%, 101%) Fund Industry Carbon Constraint Reduction from BAU (NA, 38%, 78%) Contribute annually 0.25% value of emission allowances Building Energy Efficiency Constraint Increase over 2005 (NA, 20%, 101%) Building Energy Efficiency Constraint Increase over 2005 (NA, NA, 45%) Building Energy Efficiency Constraint Increase over 2005 (20%, 45%, 113%) Building Energy Efficiency Constraint Increase over 2005 (NA, 20%, 101%) Building Energy Efficiency Constraint Increase over 2005 (NA, 20%, 101%) Building Energy Efficiency Constraint Increase over 2005 (NA, 20%, 101%)

Background on the Reference Scenario

The Reference Case: Growing Economies trillion 2000 U.S. $ MER billion 10 9 8 7 6 5 4 3 2 1 0 350 300 250 200 150 100 50 0 Population 2005 2020 2035 2050 2065 2080 2095 GDP 2005 2020 2035 2050 2065 2080 2095 USA Japan Former Soviet Union Europe Canada Australia_NZ Southeast Asia Middle East Latin America Korea India China Africa USA Japan Former Soviet Union Europe Canada Australia_NZ Southeast Asia Middle East Latin America Korea India China Africa The reference scenario envisions a growing global economy with an evolution in the distribution of economic activity.

Overview of Technology Assumptions Abundant fossil resources An eventual decline in conventional crude production accompanied by a gradual increase in production from unconventional sources Nuclear competitive with fossil electricity sources CCS available at reasonable cost with no limits on deployment in most regions Wind competitive in the near-term, solar later; limits on wind supply, and backup requirements for solar and wind on the grid Roughly 1% annual improvement in end use efficiency globally Technology assumptions from: Clarke, L., M.A. Wise, J.A. Edmonds, M. Placet, P. Kyle, K. Calvin, S. Kim, S. Smith. 2008. CO2 Emissions Mitigation and Technological Advance: An Updated Analysis of Advanced Technology Scenarios (Scenarios Updated January 2009). PNNL-18075 (December, 2008).. Available at http://www.pnl.gov/science/pdf/pnnl18075.pdf

Thinking About Pathways to 450 ppmv

Mitigation: A Long-Term Strategic Challenge Global Fossil Fuel Carbon Emissions Gigatons per Year - 20 15 10 5 Historical Emissions GTSP_750 GTSP_650 GTSP_550 GTSP_450 GTSP Reference Case 1850 1900 1950 2000 2050 2100 2150 2200 2250 2300 Fossil Fuel Carbon Emissions Historic & 2005 to 2100 1750-2005 GTSP Ref 750 ppm 650 ppm 550 ppm 450 ppm 300 GtC 1430 GtC 1200 GtC 1040 GtC 862 GtC 480 GtC Stabilizing CO 2 concentrations at any level means that global CO 2 emissions must peak and then decline forever.

Mitigation in 2005-2050 2050 is Just the Start 100% 80% 60% 40% 20% Emissions Mitigation 2005 to 2050 and 2050 to 2095 0% 2005 to 2050 2050 to 2095 750 ppm 650 ppm 550 ppm 450 ppm The bulk of emissions reductions will need to take place beyond 2050. The tighter the concentration, the greater emissions reductions in the near-term. Ultimately, achieving largescale future reductions will require that all countries and sectors participate in mitigation. These scenarios explore differing policy architectures on a transition toward a comprehensive long-term policy regime. From Edmonds, J., Wise, M., Dooley, J., Kim, S., Smith, S., Runci, P., Clarke, L., Malone, E., and Stokes, G., 2007, Global Energy Technology Strategy, Addressing Climate Change: Phase 2 Findings from an International Public- Private Sponsored Research Program, Battelle Memorial Institute.

We are considering transition measures through 2050 on the path to 450 ppmv stabilization. What is a reasonable transition emissions pathway through 2050? Global emissions consistent with fully-efficient pathways. Concentrations should be on a path to roughly 450 ppmv, and there should be some degree of economic balancing between near- and mid-term reductions Limited reliance on overshoot and negative emissions. A wide range of concentration levels are viable in the very long-term given the option for overshoot, particularly if bio&ccs is available. These scenarios will not be dramatically dependent on overshoot and/or negative emissions. A smooth transition to fuller coverage and market-based mechanisms after 2050. The distribution of emissions among sectors and regions in 2050 should not deviate dramatically from distribution in efficient solution. Global emissions through 2050 should roughly match efficient, long-term stabilization pathways.

There are multiple global emissions pathways to any long-term target Emissions (GtC/yr) 16 14 12 10 8 6 4 2 0 2000 2020 2040 2060 2080 2100 Reference 450 OS, 5%, Land Policy 450 OS, 5%, No Land Policy 450 OS, 5%, No Bio 450 OS, 5%, No CCS 450 Stab, 5%, Land Policy 450 Stab, 5%, No Land Policy, No Bio 450 Stab, 5%, No Land Policy, No Bio, No CCS CCSP Level 1 Fossil and Industrial emissions pathway depends on (1) discount rate, (2) overshoot versus stabilization, (3) emissions drivers (e.g., population, GDP), (4) technology (e.g., bio&ccs), (5) coverage (e.g., is terrestrial carbon priced)

The emissions pathway we will be choosing will roughly fit a 450 ppmv scenario 25 20 15 Reference: Annex 1 Reference: Non-Annex 1 Reference: Global 450: Annex 1 450: Non-Annex 1 450: Global Target Path: Global GtC/yr 10 5 0 1990 2005 2020 2035 2050 2065 2080 2095

Overview of Results

To Keep in Mind in Interpreting the Results In each scenario, important to distinguish between broad architecture and stringency of assumed policies Architecture: the mix of instruments (e.g., economy-wide caps) Stringency: the numbers (e.g., the specific cap levels) Equity and efficiency (cost-effectiveness) interact but are not the same It is feasible to have equitable distributions of costs that are not cost-effective and vice versa It is important to distinguish between costs with and without trading This analysis does not address the economic benefits of avoided climate impacts

CO 2 Concentrations through 2095 800 700 600 500 ppm 400 300 200 100 0 Reference Efficient 650 Efficient 550 Efficient 450 1A 550 1A 450 1B 450 2 450 3 550 3 450 2005 2020 2035 2050 2065 2080 2095

Annual CO 2 Emissions through 2095 GtC/yr 25 20 15 10 Reference Efficient 650 Efficient 550 Efficient 450 1A 550 1A 450 1B 450 2 450 3 550 3 450 5 0 2005 2020 2035 2050 2065 2080 2095

Annual CO 2 Emissions through 2050 18 16 14 12 Reference Efficient 650 Efficient 550 Efficient 450 1A 550 1A 450 1B 450 2 450 3 550 3 450 GtC/yr 10 8 6 4 2 0 2005 2020 2035 2050

Global Emissions and Costs: 2020 0.25% Costs (Fraction of GDP) 0.20% 0.15% 0.10% 0.05% 0.00% 0% 5% 10% 15% 20% 25% Efficient 650 Efficient 550 Efficient 450 1A 550 1A 450 1B 450 2 450 3 550 3 450 Emissions Reduction Note that different stringencies could lead to different efficiencies.

Global Emissions and Costs: 2035 0.70% Costs (Fraction of GDP) 0.60% 0.50% 0.40% 0.30% 0.20% 0.10% 0.00% 0% 10% 20% 30% 40% Emissions Reduction Efficient 650 Efficient 550 Efficient 450 1A 550 1A 450 1B 450 2 450 3 550 3 450

Global Emissions and Costs: 2050 4.00% Costs (Fraction of GDP) 3.50% 3.00% 2.50% 2.00% 1.50% 1.00% 0.50% 0.00% 0% 20% 40% 60% 80% Emissions Reduction Efficient 650 Efficient 550 Efficient 450 1A 550 1A 450 1B 450 2 450 3 550 3 450

The Effect of the Increasing Challenge Costs (Fraction of GDP) 4.00% 3.50% 3.00% 2.50% 2.00% 1.50% 1.00% Electric sector lowcarbon standard not eliminating freely-emitting coal. Coverage of policy commitments must apply to virtually all sectors in the developing regions. All sectors covered, including CO2- based sectoral policies. Efficient 650 Efficient 550 Efficient 450 1A 550 1A 450 1B 450 2 450 3 550 0.50% 3 450 0.00% Without expanded 0% 20% 40% 60% policy 80% coverage, limited coverage Emissions Reduction makes 2050 infeasible.

The Increasing Challenge The efficiency losses from the multi-track approaches explored in this analysis may be moderate in the near-term But over time, as the abatement burden increases, they become increasingly acute.

Global Emissions and Costs: 2095 1.00% Costs (Fraction of GDP) 0.90% 0.80% 0.70% 0.60% 0.50% 0.40% 0.30% 0.20% 0.10% 0.00% 0% 20% 40% 60% 80% 100% Emissions Reduction Efficient 650 Efficient 550 Efficient 450 1A 550 1A 450 1B 450 2 450 3 550 3 450

14.0 12.0 10.0 8.0 6.0 4.0 2.0 0.0 Industry Buildings Transport Electricity Reference Efficient 650 Efficient 550 Efficient 450 1A 550 3 550 1A 450 GtC/yr 1B 450 2 450 3 450 Sectoral Emissions: 2035 Idealized stabilization scenarios

Sectoral Emissions: 2050 18.0 16.0 14.0 12.0 10.0 8.0 6.0 4.0 2.0 0.0 Reference Efficient 650 Efficient 550 Efficient 450 1A 550 3 550 1A 450 1B 450 GtC/yr 2 450 3 450 Industry Buildings Transport Electricity Idealized stabilization scenarios

0.0% -5.0% -10.0% -15.0% -20.0% -25.0% -30.0% -35.0% -40.0% Efficient 450-45.0% -50.0% USA Japan Korea Middle East Canada Australia_NZ Europe Latin America Southeast Asia Former Soviet Union China Africa Abatement Relative to Reference India Abatement by Region: 2035 With trading, emissions reductions are completed where they are least costly.

0.0% -0.2% -0.4% -0.6% -0.8% -1.0% Efficient 450-1.2% Europe Japan USA Canada Korea Australia_NZ Latin America Southeast Asia Middle East China India Africa Abatement Cost Relative to GDP Former Soviet Union Abatement Cost by Region: 2035 With trading, emissions reductions are completed where they are least costly.

Abatement by Region: 2035 Abatement Relative to Reference 0.0% -10.0% -20.0% -30.0% -40.0% -50.0% -60.0% Sorted by the distribution of abatement in 1A 450 Efficient 450 1A 450 1B 450 Africa Middle East Latin America Southeast Asia India China Korea Policy approaches or sectoral approaches can lead to a different distribution of emissions reductions. Japan USA Europe Canada Former Soviet Union Australia_NZ

Abatement by Region: 2035 Abatement Relative to Reference 0.0% -10.0% -20.0% -30.0% -40.0% -50.0% -60.0% -70.0% Sorted by the distribution of abatement in 3 450 Efficient 450 2 450 3 450 Middle East Africa India Southeast Asia Latin America China Korea Policy approaches or sectoral approaches can lead to a different distribution of emissions reductions. Former Soviet Union Japan Europe USA Canada Australia_NZ

0.5% 0.0% -0.5% -1.0% -1.5% -2.0% India China Africa Southeast Asia Latin America Middle East Japan Korea USA Europe Cost Relative to GDP Canada Australia_NZ Former Soviet Union Regional Cost Distribution: 2035 Scenario 1B 450 Abatement Cost w/o Trading Financial Flows from Trading Abatement Cost +/- Trading Trading redistributes costs.

CCS Deployment Fund 0.20 EJ/yr 100 90 80 70 60 50 40 30 20 10 0 Global Electricity Production, CCS Fund Recipients: 2035 Reference Efficient 450 Efficient 550 Efficient 650 1A 550 1A 450 1B 450 2 450 3 550 3 450 geothermal solar wind hydro nuclear biomass coal w/ ccs coal gas w/ ccs gas oil w/ ccs oil Trillion U.S. 2000$ 0.15 0.10 0.05 2 450 CCS fund increases CCS fund in recipient nations; lowers cost of electricity, reducing impact on total demand 0.00 2005 2020 2035 2050

Adaptation/Technology Funds Billion U.S. 2000$ 2.5 2.0 1.5 1.0 0.5 2 450 3 550 3 450 0.0 2005 2020 2035 2050

Summary Ultimately, all sectors and regions must participate in emissions mitigation to achieve stabilization These scenarios have explored near- and mid-term policy architectures in the context of long-term stabilization A range of architectures could lead to emissions reductions in the near- and mid-term that are consistent with long-term stabilization at levels at roughly 450 ppmv But a transition toward broad coverage will be required toward mid-century to contain costs. The greater the overlap and intersections between policy approaches, the more difficult to predict the outcome Deviations from full trading will reduce the absolute economic efficiency of any architecture; the degree of deviation depends on the mechanisms included in the architecture for trading A variety of trading mechanisms can be used to redistribute costs among regions

Concluding Thoughts Effectiveness A range of policy mixes can produce a near/mediumterm effort consistent with long-term stabilization Fairness A range of policy mixes can produce a reasonable distribution of cost Efficiency A transition to full global trading and coverage is key to economic efficiency in the long term In the nearer term, can we tolerate some trade-off of efficiency to achieve the broad participation needed to put countries on track toward the long-term objective?

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