From principles to practice: Use of fairness and ambition considerations in nationally determined contributions

Abstract

According to the Paris Agreement, climate action must be based on equity. Countries had to submit their second Nationally Determined Contributions (NDCs) by 2025, including arguments on how the Party considers that its NDC is fair and ambitious in light of its national circumstances. This study analyses the information provided by countries in the Fairness and Ambition section of their first NDCs, focusing on the use of principles and indicators supported by international environmental law. Countries are mapped according to historical emissions per capita and GDP per capita, grouping them as Developed Countries, Developing Countries, or Least Developed Countries/Small Island Developing States. The analysis reveals that countries with the least historical responsibility and economic capacity rely most on those principles and indicators. Most countries tend to select principles favorable to their positions while avoiding those that would justify stronger mitigation efforts. Notably, developed countries generally do not base their fairness arguments on those internationally recognized principles. To enhance the robustness and comparability of arguments in NDCs, authors suggest that countries consistently report using principles aligned with international environmental law and, if possible, provide standardized indicators