Tom Wigley , the SAR, and the dawn of Earth System Modeling

1. Tom Wigley, the SAR, and the dawn of Earth System Modeling Dave Schimel With thanks to the 1995 IPCC Carbon Cycle Lead Author Team

2. The motivation for the ‘95 writing team approach The ultimate objective of this Convention and any related legal instruments that the Conference of the Parties may adopt is to achieve, in accordance with the relevant provisions of the Convention, stabilization of greenhouse gas concentrations in the atmosphere at a level that would prevent dangerous anthropogenic interference with the climate system

3. Climate to Concentrations to Emissions For a given CO2 concentration profile leading to stabilization, what anthropogenic emissions are implied? Develop historical-to-future concentration profiles. Provide these to modelers. Compute, using inverse methods, emissions consistent with the concetration profiles.

4. Proto-Earth System Modeling in the SAR • Emissions to concentrations required coupled atmosphere-ocean-land biosphere models.. • Developing concentration profiles required collaboration between geophysicists, energy sector experts and applied mathematicians. • Linking fossil fuel emissions of CO2 to radiative forcing by assumed relationships to other GHGs and aerosols required linked industrial ecology and chemistry-climate models. • GHG concentrations to climate required coupled carbon-climate and climate-sea level models. Thus, for the SAR, most of the linkages we think of as essential to ESMs were in play…

5. The Group… • Tom Wigley • Ian Enting • DominqueRaynaud • Diogenes Alves • Martin Heimann • UliSiegenthaler And (Technical Paper 3) • Michael Grubb • FortunatJoos • Robert Kauffman • Richard Moss • WanderaOgana * Plus many contributing authors and modelers

6. Results-scientific background

7. The Concentration Profiles

8. Emissions leading to stabilization

9. Future allowable emissions relative to “today’s” emissions..

10. Sensitivity to the Land Biosphere Effect on allowable emissions Effect on concentrations

11. Relationship between stabilization levels and carbon budgets-

12. KOALA (Key Ocean-Atmosphere-Land Assessments) • KOALA: Key Ocean-Atmosphere-Land Assessments. The working title of this document • Appendix A-H of KOALA required pp 66-124…. • Koala: Australian marsupial with a six-foot long appendix.

13. “New” scenarios development process: parallel vs. sequential approach (AR5, proposed) Figure from Moss et al., 2008 IGBP IPO 25-27 February, 2009 Stockholm, Sweden

14. Tom’s contributions to coupled GHG-climate modeling • Work in interdisciplinary science and at the science-policy interface of the first order of importance – there is no question in global change more important than understanding the emission-concentration-climate linkages • The actual numbers: the understanding of reductions in emissions relative to today’s derive from the SAR and have not changed greatly • The understanding of the value to society of maintaining the ocean and biotic reservoirs

15. A Portfolio of Actions “that policy makers could consider… to implement low cost and/or cost-effective measures.” • Implementing energy efficiency measures including the removal of institutional barriers to energy efficiency improvements; • Phasing out existing distortionary policies and practices that increase greenhouse gas emissions, such as some subsidies and regulations, non-internalization of environmental costs, and distortions in transport pricing; • Implementing cost-effective fuel switching measures from more to less carbon-intensive fuels and to carbon-free fuels such as renewables; • Implementing measures to enhance sinks or reservoirs of greenhouses gases such as improving forest management and land-use practices; • Implementing measures and developing new techniques for reducing methane, nitrous oxide and other greenhouse gas emissions; • Encouraging forms of international cooperation to limit greenhouse gas emissions, such as implementing coordinated carbon/energy taxes, activities implemented jointly, and tradeable quotas; • Promoting the development and implementation of national and international energy efficiency standards; • Planning and implementing measures to adapt to the consequences of climate change; • Undertaking research aimed at better understanding the causes and impacts of climate change and facilitating more effective adaptation to it; • Conducting technological research aimed at minimizing emissions of greenhouse gases from continued use of fossil fuels and developing commercial non-fossil energy sources; • Developing improved institutional mechanisms, such as improved insurance arrangements, to share the risks of damages due to climate change; • Promoting voluntary actions to reduce greenhouse gas emissions; • Promoting education and training, implementing information and advisory measures for sustainable development and consumption patterns that will facilitate climate change mitigation and adaptation. From: Technical Paper 3: Stabilization of greenhouse gases: physical, biological and socio-economic implications

16. Conclusions • Stabilizing emissions does not lead to stabilized concentrations. • Stabilization at 2xCO2 or lower requires lowering emissions to small fractions of today’s by mid-century. • The response of the biospheric and ocean carbon cycle significantly modulates the effect of emission mitigation on climate. • Understanding and managing the carbon system requires even deeper integration of biology, chemistry, economics, technology and geophysics than has occurred over the past decade.