Sharing developed countries’ post-2012 greenhouse gas emission reductions based on comparable efforts

The Bali Action Plan as adopted under the United Nations Framework Convention on Climate Change (UNFCCC) in 2007, states that Annex I (developed) countries should reduce their greenhouse gas emissions, based on comparable efforts. Within this context, we have explored various comparable effort approaches (for example, equal marginal abatement costs for all countries) for reducing emissions by the year 2020 for individual countries and regions.

In all calculations, the total reduction for Annex I countries as a group is assumed to be 30% below 1990 levels. In the analysis, we compare the reduction targets as calculated from the different approaches with the emission reductions as pledged by these countries as part of the Copenhagen Accord, as drafted under the UNFCCC in 2009.

Our analysis indicates that the different elements in these calculations may cause a diversity in outcomes and that, therefore, individual countries may favour certain elements over others. These elements include:

  1. the choice of the approach itself (the same approach may produce very different outcomes for countries with diverging national circumstances, such as Canada and Russia);
  2. the reference year (such as 1990 or 2006 emissions, is very important for countries with an increase in emissions since 1990 (e.g. the United States, Canada) or for those that have lower emission levels (e.g. Russia, the Ukraine));
  3. rules on land use (these are important for countries with large forest areas).

It should be noted that the stringency of the individual countries’ reductions as pledged, differs substantially from the stringency of the reduction targets calculated from the effort-sharing approaches.

The current pledges by both the European Union and the United States, are lower than the reductions that would be obtained in the effort-sharing approaches for a 30% overall reduction in Annex I countries.


Michel G. J. den Elzen, Niklas Höhne, Markus M. Hagemann, Jasper van Vliet and Detlef P. van Vuuren


Publication title
Sharing developed countries’ post-2012 greenhouse gas emission reductions based on comparable efforts
Publication date
24 April 2010
Publication type
Mitigation and Adaptation Strategies for Global Change
Product number