The Perspective piece, Ethical Choices behind Quantifications of Fair Contributions under the Paris Agreement, published in Nature Climate Change, comes as UN climate negotiators are expected to release new national plans for climate action ahead of climate negotiations this year in Glasgow, Scotland and defend them as “fair and ambitious”.

The piece evaluates a selection of recent effort-sharing studies to determine whether they are explicit about the ethical choices underlying their analysis or not. Reviewing sixteen studies that quantify equitable effort sharing between countries under the Paris Agreement, the authors find that nearly two thirds (ten studies) present themselves as neutral or value-free, despite being limited to a small and biased subset of ethical perspectives on effort-sharing that tend to favour wealthier countries.

In particular, “grandfathering” of emissions, where countries argue that their status as high emitters justifies continued high emissions, should not be included in equity assessments of global climate action. This is a key source of the systematic bias in favour of wealthier, higher emitting countries.

Other studies claim objectivity by averaging a spectrum of equity approaches, commonly choosing a subset that exclude important ethical concepts. For instance, when many analyses quantify a country’s capacity to allocate resources to a global climate effort, they routinely treat a dollar earned by a poor citizen as wholly equivalent to a dollar earned by a rich citizen.

One prominent assessment, the Climate Action Tracker (CAT), generates a “fair share” range of emissions allowances for each country that is widely used to assess countries’ mitigation ambition by media, academia, civil society and governments. The CAT method excludes a large number of studies for being statistical outliers, excluding whole categories of ethical positions.

The authors propose new guidelines that emphasize transparency in communicating the ethical underpinnings of assessments of climate action and for developing equity research that is policy relevant but not ethically neutral. The guidelines suggest that:

  • studies of equitable distribution of climate efforts should not claim value-neutrality
  • analysis needs to ensure that the losses of those who are potentially marginalized remain clearly visible, and
  • analytical work should aim to inform rather than supplant the political process.