Blog Post

Comparing Emissions Mitigation Efforts on the International Stage: Evaluating Metrics

Jul 10, 2015 | William A. Pizer

The success of international climate change policy going forward depends on the ability to measure and compare both commitments and subsequent actions across a large number of countries. Policymakers and negotiators from around the world will need to understand how the mitigation efforts of their peers stack up in order to ensure comparable effort across the board to meet mitigation goals.

Toward this end, the international community will require a well-designed framework for evaluating comparability of effort across nations to provide the foundation for a successful pledge and review regime. As my colleague Joe Aldy and I spell out in a recent article for Resources magazine, ideal metrics would ultimately be defined by the following principles:

  • Comprehensive. A metric should characterize the entire effort actively undertaken by a country to achieve its mitigation commitment—and exclude non-policy drivers of climate outcomes.
  • Measurable and replicable. To enhance credibility and facilitate transparency, a metric should consistently and accurately calculate effort based on publicly available information.
  • Universal: Climate change is a global challenge—metrics should be accessible and functional for as wide a range of countries as possible.

We take this work a step further in a new RFF discussion paper, with Keigo Akimoto from Japan’s Research Institute of Innovative Technology for the Earth, and propose a framework for evaluating six types of mitigation effort metrics. Included in this framework is a template for organizing metrics for both the examination of future targets (including INDCs) and the review of ongoing actions. Metrics that are relatively easy to observe and measure—such as total emissions or emissions prices—can be far removed from the concept of effort itself (and related policy action), requiring us to look further. But more helpful effort-based metrics, such as emissions reductions, are without question harder to measure and require the use of modeling tools that may result in divergent estimates.

In our new paper, we use a modeling tool developed at the Research Institute of Innovative Technology for the Earth to generate preliminary effort assessments for post-2020 mitigation contributions that have been proposed by a number of the world’s largest economies, including China, the European Union, Russia, and the United States.* We also outline sources of uncertainty in our country-by-country evaluation and discuss how researchers and policymakers can facilitate the adoption of transparent and successful metrics.

For more insight into these opportunities as well as a complete breakdown of our results, read the full paper.


*At the time this paper was written, China had not yet made its late-June INDC announcement. The relevant calculations in the paper are based on China’s November 2014 announcement.