Limitations of Single-Basket Trading: Lessons from the Montreal Protocol for Climate Policy John S. Daniel National Oceanic and Atmospheric Administration Chemical Sciences Division Boulder, Colorado USA Implications of the particular control strategy to its success Limitations of Single-Basket Trading: Lessons from the Montreal Protocol for Climate Policy, Daniel, Solomon, Sanford, McFarland, Fuglestvedt, and Friedlingstein, Climatic Change, 2012 (online 2011).

Limitations of Single-Basket Trading: Lessons from the Montreal Protocol for Climate Policy John S. Daniel National Oceanic and Atmospheric Administration Chemical Sciences Division Boulder, Colorado USA Montreal Protocol Success A Lesson for Climate Policy Implications for HFC Policy Implications of the particular control strategy to its success Limitations of Single-Basket Trading: Lessons from the Montreal Protocol for Climate Policy, Daniel, Solomon, Sanford, McFarland, Fuglestvedt, and Friedlingstein, Climatic Change, 2012 (online 2011).

Montreal Protocol Multiple Basket Approach • Groups of gases controlled separately (e.g., CFCs, HCFCs, halons, etc.) Various groups diff phaseout schedules Reductions of Gases within a group could be traded with reductions of other gases in the same group

Montreal Protocol Multiple Basket Approach • Groups of gases controlled separately (e.g., CFCs, HCFCs, halons, etc.) • No “trading” among groups

Montreal Protocol Multiple Basket Approach • Groups of gases controlled separately (e.g., CFCs, HCFCs, halons, etc.) • No “trading” among groups • Highly successful Adapted from Velders et al, PNAS, 2007 No Protocol A Measure Of Success

Montreal Protocol Multiple Basket Approach • Groups of gases controlled separately (e.g., CFCs, HCFCs, halons, etc.) • No “trading” among groups • Highly successful • CFCs/HCFCs Illustration Adapted from Velders et al, PNAS, 2007 No Protocol I will use CFCs and HCFCs to explore the hypothetical impacts of a different control strategy – one where CFC and HCFC production could be traded A Measure Of Success

CFC/HCFC Contribution to O3 Depletion Obs - based Projections Do this with equiv eff strat chlorine or EESC, which is a metric that relates to the amount of chlorine and bromine available to destroy strat ozone Discuss curve ‘what if, when MP controls went into force, the ODP-weighted emission were kept identical to those used to generate this curve, but all emissions were traded to HCFC emissions, with no CFC emissions”

Impact of a Trade to HCFCs Maybe relate ss ODPs to time-dependent ODPs

Single-Basket Range of O3 Depletion Peak uncertainty Fast phaseout leads to not much spread in future possibilities

Kyoto Protocol Single Basket Approach PFCs CO2 CH4 N2O HFCs SF6

Kyoto Protocol Single Basket Approach PFCs CO2 CH4 N2O HFCs SF6 2010 Radiative Forcing

Kyoto Protocol Single Basket Approach PFCs CO2 CH4 N2O HFCs SF6 2010 Radiative Forcing

CO2/CH4 Impact on Climate (RCP4.5)

Impact of a Trade to All CH4 Emissions Trades begin in about 2040

Impact of a Trade to All CO2 Emissions

Ambiguity of Single Basket if the GWP-weighted emission level is prescribed for every year, depending on how trading occurs, the range of T increases by 2400 will be 2-4C, with the range continuing to expand

Implications for HFCs Velders et al, PNAS, 2009

Radiative Forcing Change Implications for HFCs Radiative Forcing Change from 2010 to 2050 (RCP8.5) 1.8 Velders et al, PNAS, 2009

Implications for HFCs This can all be avoided Velders, PNAS, 2009

Implications for HFCs This can all be avoided Potential Long-term penalty Velders, PNAS, 2009

N2O and Ozone Depletion Ravishankara et al., 2009

Conclusions The Montreal Protocol successfully implemented a multi-basket approach to deal with the international problem of stratospheric ozone depletion. A single-basket approach, as used in the Kyoto Protocol, can lead to some level of ambiguity in the climate impact of regulation. If regulation on some group of gases (e.g., HFCs) has the inadvertent affect of delaying CO2 regulation, this will have multi-century climate implications. Perhaps mention advantage of HFC phaseout in terms of avoiding future forcing – and in a multi-basket approach, you know what you will get Then point out issue 3