Common Metrics

Policy Goals and Frameworks

An EU Perspective

Frank McGovern,

4th April 2012, Bonn

Contents

• History of metrics and their use in the UNFCCC• The benefits of the Basket approach• What should a gas equivalent metrics do?• General principles on the characteristics of metrics• Dealing with problems in the design • Implications of changing metric• Conclusion

History of GWPs in the UNFCCC

Article 2. Objective: stabilisation of atmospheric greenhouse gas concentrations at a level that would prevent dangerous anthropogenic interference with the climate system

•Long lived greenhouse gases are the key challenge. •Process must facilitate actions on these gases.

History of GWPs in the UNFCCC

• Develop, periodically update, publish and make available to the Conference of national inventories of anthropogenic emissions by sources and removals by sinks of all greenhouse gases not controlled by the Montreal Protocol, using comparable methodologies to be agreed upon by the Conference of the Parties;

• Kyoto Protocol Article 3: Ensure that their aggregate anthropogenic carbon dioxide equivalent emissions of the greenhouse gases listed in Annex A.

• Carbon dioxide (C02)

• Methane (CH4)

• Nitrous oxide (N20)

• Hydrofluorocarbons (HFCs)

• Perfluorocarbons (PFCs)

• Sulphur hexafluoride (SF6)

The benefits of the basket approach

• Basket • Enables more policy options and flexibilities • Provides a economy wide signal• Targets the key gases • Avoids negotiations on targets for individual gases• Economically efficient overall

• Key Requirement • An agreed common metric to aggregate emissions

What should a gas equivalent metric do?

• Provide a robust scientific basis for quantifying and comparing the potential climate impacts of the basket of GHGs

• Provide a common view of the relative importance of emissions• Enable an agreed basis for target setting and tracking progress on

targets over defined periods.• Allow fungible trading of gases.• Avoids biases and perverse outcomes • Provide a fair basis for assessing equivalent effort.• Support achievement of global temperature goals

General principles on the characteristics

• Use for well mixed and evenly distributed gases, i.e., long life GHG• Unbiased over the basket of gases• Easy to understand and links with responsibility• Practical and stable• Based on objective physical properties  • Facilitate cost-effective abatement• Useable for achievement of the objectives and mechanisms of the

convention in an appropriate timeframe• Acceptable to the Parties

Dealing with problems in the design

IPCC recognised shortcomings of GWPs•Integration period result in different values

•Revisions are required based on changes in atmospheric concentrations

•Difficult to extend to short-lived radiative forcers

• Other metrics also have shortcomings

Implications of changing metricRequires understanding of •The differences between concepts and scientific basis •The advantages/disadvantages, assumptions, limitations and uncertainties involved•The impacts on mitigation actions, targets and the markets

Also requires consideration of •Time-scales for implementing changes of metrics

• E.g. The current metrics are used domestic legislation such as EU ETS and require certainty over defined operational periods

•Reworking and re-evaluation of inventories •Communications to key stakeholders and the public

Conclusions

GWP has been adopted and reconfirmed by Parties to UNFCCC for determination of GHG emissions

GWP has proven to be a robust and practical metric

Other metrics also have shortcomings and have not been subject to test through use under the UNFCCC

Changing metrics would require a major revision of assessment of emissions and has implications for policies, markets, target setting and monitoring progress

The EU supports the continued use of GWPs under the UNFCCC and looks forward to consideration of relevant material in the AR5

Acknowledgements

With thanks to: Myles Allen, Tina Christensen, Bill Collins,Jolene Cook,Laila Gohar, Anke Herold, Nick Howarth, Phillip O’Brien, Alex Lorenz , Malte Meinshausen, Keith Shine, Christiane Textor, David Warrilow.