Summing Up Emissions Reduction Pledges: The State of the Art

April 13, 2010 by Elizabeth Sawin

Judging from the  well-attended  side-event on the first day of last week’s UNFCCC session there appears to be growing momentum to  assess the question: is it adding up? Is the collective benefit of the pledges enough to deliver our goals for protecting the climate?

Panelists representing five groups of analysts and modelers (including Climate Interactive) who have been working to estimate the collective benefit of the emissions pledges associated with the Copenhagen Accord gathered to describe not only what they are finding, but also some of the biggest challenges they are encountering.

What the groups are finding won’t be surprising to followers of Climate Interactive and the Climate Scoreboard: there’s a gap. Current pledges do not create a trajectory either in the near-term (2020) or the long-term consistent with limiting temperature increase to 2°C (3.6°F) as called for in the Copenhagen Accord and certainly not 1.5°C (2.7°C) as called for by hundreds of developing countries. The slide reproduced here, shows the assessments of that gap from the different groups. The details of each study differ, but the overall message, as panelist Niklas Hoehne from EcoFys articulated most clearly, is clear: a gap remains.

Knowing that the gap exists is discouraging, of course, but there is hope to be found in the fact that this kind of analysis is happening at all, let alone from five different groups, and in the fact that the UNFCCC parties themselves are calling for exactly this kind of information to steer their deliberations.

The panelists also discussed some of the biggest challenges they are finding in adding up the pledges:

  1. Lack of clarity and consistency in the formulation of the pledges. Which gases do they refer to? What assumptions are made about land-use changes? How are offsets being considered? When a pledge is relative to a ‘business as usual’ framework, how is that BAU emissions trajectory specified? Parties to the UNFCCC could help a lot by agreeing to and sticking with a common, clear, and complete formula for reporting pledges.

  2. Challenges in assessing comparability of effort. Indicating how much “effort”  a given country’s pledge represents is not simple to assess, and formulations for doing so differ, but some sense of how sincere a country’s effort might be is a question that many, from civil society advocates to parties themselves, want to understand.

  3. How to best represent long-term outcomes of current policy choices? Making long-term estimates of impacts of current policy choices on greenhouse gas concentrations or temperature requires making assumptions about countries’ emissions beyond commitment periods and there is not one obvious future to choose. If emissions fall to 2020 will they continue to fall, level out, or even rebound and begin to rise thereafter? Sharing policy insights about the long-term might be challenging, but, if all policy attention focuses only on the short-term, there is the danger of optimizing policy decisions to meet 2020 targets without laying the ground-work - from research and development, to infrastructure build-out, to behavior change - that will enable emissions to continue to fall as much as needed past 2020.

This last topic in particular has caught the eye of the Climate Interactive team, because the field of system dynamics is full of examples where limiting the dynamic view to the short term obscured critical insights about the behavior of the system - a topic for a future post.