1. Integrating Ethics into Graduate Training in the Environment Sciences Series Unit 6: Ethical issues implicit in cost- benefit analyses of climate management AUTHOR: KENNETH DAVIS Department of Meteorology Penn State University MODIFIED BY: SETH BAUM Department of Geography Penn State University With input from Klaus Keller and Nancy Tuana

2. –What value judgments are embedded in cost- benefit analyses of optimal climate management strategies? –Can we articulate the value judgments that are implicit in a given analysis framework? –Is there a valid case for “ethical uncertainty” in climate management cost-benefit analyses? –What, if any, are the implications for your research? –What are the implications for ethical use of the results of such cost-benefit analyses? 2 Questions for discussion

3. –Review governing equations and results from two important cost-benefit analyses Nordhaus, 1992 (“N 1992” for short) McInerny and Keller, 2007 (“MK 2007” for short) 3 Background

4. Governing Equations (N 1992) 4 Eqn. 2, N 1992 Eqn. 4, N 1992 Eqn. 1, N 1992 Eqn. 3, N 1992 Eqn. 13, N 1992

5. Governing Equations (MK 2007) 5 Eqn. 2, MK 2007 Eqn. 1, MK 2007 Constraint: Prob[MOC collapse] ≤ threshold - Thresholds: 1, 0.1, 0.05, 0.01 Sec. 5-6, MK 2007

6. Results: Abatement (N 1992) 6 Abatement Rate = Emissions under abatement Uncontrolled emissions Optimal Uncontrolled Emissions Stabilization Climate Stabilization

7. Results: GHG’s (N 1992) 7 Atmospheric greenhouse gas concentrations in tons C. Optimal Uncontrolled Emissions Stabilization Climate Stabilization

8. Results: Temperature (N 1992) 8 Optimal Uncontrolled Emissions Stabilization Climate Stabilization Global temperature increase (°C) relative to 1900.

9. Results: Carbon Tax (N 1992) 9 Optimal Uncontrolled Emissions Stabilization Climate Stabilization Global carbon tax rate in US $ per ton C. Note: $1000 per ton C = $2.66 per gallon.

10. Results: Economic Output (N 1992) 10 Optimal Uncontrolled Emissions Stabilization Climate Stabilization Geoengineering Difference in output = Output – Output with no abatement Note: Economic output measured in US $.

11. Results: Consumption (N 1992) 11 Note: Consumption measured in US $.

12. Uncertainty: MOC Damage (MK 2007) 12 Percent gross world product lost due to meridional overturning circulation (MOC) collapse N 1992: No MOC  0% GWP

13. Uncertainty: Climate Sensitivity (MK 2007) 13 Global temperature increase due to doubling of atmospheric CO 2 concentration N 1992: λ* = 3°C

14. Uncertainty: Population Growth (MK 2007) 14 Decadal decline in population growth rate N 1992: declines slowly, eventually stabilizing

15. Uncertainty: CO 2 :GWP Growth (MK 2007) 15 Decadal decline in rate of growth of CO 2 :GWP ratio N 1992: not specified

16. Results: Abatement (MK 2007) 16 Abatement Rate = Emissions under abatement Uncontrolled emissions

17. –What value judgments are embedded in cost- benefit analyses of optimal climate management strategies? 17 Questions for discussion

18. Governing Equations (N 1992) 18 Eqn. 2, N 1992 Eqn. 4, N 1992 Eqn. 1, N 1992 Eqn. 3, N 1992 Eqn. 13, N 1992

19. Governing Equations (MK 2007) 19 Eqn. 2, MK 2007 Eqn. 1, MK 2007 Constraint: Prob[MOC collapse] ≤ threshold - Thresholds: 1, 0.1, 0.05, 0.01 Sec. 5-6, MK 2007

20. –Can we articulate the value judgments that are implicit in a given analysis framework? Can we formulate valid alternative value systems that could be applied to the analysis framework? 20 Questions for discussion

21. –Is there a valid case for “ethical uncertainty” in optimal climate management cost-benefit analyses? If so, can this be evaluated in a quantitative fashion? If so, can we think of any past societal issues that provide an example of these “ethical uncertainties”? Do these shed any light on the current situation? 21 Questions for discussion

22. –What, if any, are the implications for your research? 22 Questions for discussion

23. –What are the implications for ethical use of the results of such cost-benefit analyses? How should climate scientists present their research results? –Is this limited to those who perform climate management studies? –Are Nordhaus 92 and McInerny and Keller 07 being ethically responsible? How should decision-makers use the results of cost- benefit analyses? Is there an ethical imperative to close the gap between scientific results and their sound application to policy? Who bears this responsibility? 23 Questions for discussion

24. Examples in the literature for further reading Tol 2001 Considers broader range of ethical frameworks Stern 2007 Landmark report commissioned by UK Government Baum 2007 Accessible discussion of ethical and modeling issues 24

25. Additional information Ethical guidelines in statistics, engineering, science (but not quantitative ethics): –ASA Ethical Guidelines for Statistical Practice, published by the American Statistical Association: http://www.tcnj.edu/~asaethic/asagui.html –The Online Ethics Center for Engineering and Science: http://onlineethics.org/index.html http://onlineethics.org/index.html Ethics of climate change –http://climateEthics.orghttp://climateEthics.org 25