Using Montreal Protocol to Protect the Climate Kristen N. Taddonio U.S. Environmental Protection Agency Stephen O. Andersen Co-Chair, Technology & Economic Assessment Panel

The Montreal Protocol is successfully protecting ozone > The Montreal Protocol has slowed and reversed the accumulation of ozone depleting substances (ODSs) in the stratosphere. (Effective stratospheric chlorine is the weighted sum of chlorine and bromine gases in the stratosphere.) UNEP/WMO Ozone Assessment, 2006

Transition from CFC to HCFC or HFC reduced greenhouse gas emissions ~10 time or more Example: Mobile air conditioning sector switched from CFC 12 (GWP 10,900 ODP 1) to HFC-134a (GWP 1,430 ODP 0) UNEP/WMO Ozone Assessment, 2006 (ODPs)(GWPs) CFC-11 = 1CO 2 = 1

G. Velders et al., PNAS, 2007 Montreal Protocol protection of climate Tan Line = Global CO2 emissions Green line = The CO2-equivalent of the ODS emissions that would have occurred if Molina and Rowland had not warned the world about CFCs. Note that the climate impact would have been greater than global CO2 emissions. Blue line = The CO2-equivalent of the ODS emissions that would have occurred without the Montreal Protocol. Black line = The CO2-equivalent of ODS emissions. Thanks to the Montreal Protocol, this is low. The Montreal Protocol has also achieved extraordinary greenhouse gas reductions

Climate benefits of the Montreal Protocol By phasing out ozone-depleting substances, the world has avoided the equivalent of 135 billion gigatons of carbon dioxide equivalent between the 1990 and 2010, equivalent to about 13% of accumulated emissions of CO2 from human activities. This effectively delayed climate change by 7 to 12 years. As of 2010, net GWP-weighted emissions reductions from ODSs are about 11 Gt CO2-eq yr. This is 5-6 times the reduction target of the first commitment period ( ) of the Kyoto Protocol (2 Gt CO2-eq yr). G. Velders et al., PNAS, 2007

However, larger than expected growth in use and emissions of HFCs and HCFCs threatens to overwhelm the climate benefits achieved by the Montreal Protocol.

The large contribution of projected HFC emissions to future climate forcing Based on the most recent trends, HFC emissions in 2050: 5.5–8.8 GtCO 2 -eq yr Equivalent to 9–19% of global CO 2 emissions, assuming business-as-usual Velders et al., PNAS (2009)

Article 5 Countries Leading the Way to Use Montreal Protocol to Further Protect the Climate The 2007 HCFC accelerated phaseout –Proposed by Article 5 countries –First time developing countries committed to a binding agreement to reduce greenhouse gas emissions. Decision XIX/6 (9.) “To encourage Parties to promote the selection of alternatives to HCFCs that minimize environmental impacts, in particular impacts on climate….” (2007) Requests to the TEAP –Evaluate alternatives to HCFCs –Environmentally sound management of ODS banks Proposals to move HFCs to Montreal Protocol

HCFC Phaseout: Unprecedented Climate Opportunity CFC, HCFC or HFC ApplicationLow-GWP Alternatives Domestic Refrigerators and FreezersHC-600a HC-600a & HC-290 blend Unsaturated HFCs (also called HFOs) Commercial RefrigerationHF-600a HC-290 Carbon dioxide Large Refrigeration SystemsAmmonia Carbon dioxide Hydrocarbons Air-cooled Air Conditioning & Heat Pumps HCFC-22 > R410a, R407c Hydrocarbons in systems with small refrigerant charge HFOs ChillersAmmonia Hydrocarbons Carbon Dioxide HFOs Mobile Air ConditioningHFO-1234yf Carbon Dioxide Polyurethane (PU) foamsHydrocarbons (except in spray foam) CO2 (water), Supercritical CO2 HFO-1234ze Alternative Insulation (glass fibre, rock fibre) XPS foamsCO2 Water TEAP Task Force Decision XX/8 Report, May 2009

Life-Cycle Climate Performance Key to Success No alternative is a “one-size-fits all” solution Energy efficiency must be taken into account Goal: highest LCCP, not just lowest GWP! –Example: Mobile Air Conditioning –Alternatives CO2, HFC-152a, HFC-1234yf Important for sectors to identify highest LCCP alternatives as phase-out proceeds

The Montreal Protocol has strong climate benefits, and can achieve even greater greenhouse gas reductions.

More Information TEAP Reports –“Environmentally Sound Management of Banks of Ozone-Depleting Substances” (June 2009) –“Assessment of Alternative to HCFCs and HFCs” (May 2009) –Available at: Guus J.M. Velders, Stephen O. Andersen, John S. Daniel, David W. Fahey, and Mack McFarland. “The importance of the Montreal Protocol in protecting climate.” Proceedings of the National Academy of Science (PNAS) March 20, 2007 vol. 104 no Guus J. M. Velders, David W. Fahey, John S. Daniel, Mack McFarland, and Stephen O. Andersen. “The large contribution of projected HFC emissions to future climate forcing” PNAS July 7, 2009 vol. 106 no Available on-line at:

More Information Kristen N. Taddonio Stephen O. Andersen