A Bottom-Up, Non-Cooperative Approach to Climate Change Control: Assessment and Comparison of Nationally Determined Contributions (NDCs)

International negotiations on climate change control are moving away from a global cooperative agreement (at least from the ambition to achieve it) to adopt a bottom-up framework composed of unilateral pledges of domestic measures and policies. This shift from cooperative to voluntary actions to control GHG emissions already started in Copenhagen at COP 15 in 2007 and became a platform formally adopted by a large number of countries in Paris at COP 21. The new architecture calls for a mechanism to review the nationally determined contributions (NDCs) of the various signatories and assess their adequacy. Most importantly, countries’ voluntary pledges need to be compared to assess the fairness, and not only the effectiveness, of the resulting outcome. This assessment is crucial to support future, more ambitious, commitments to reduce GHG emissions. It is therefore important to identify criteria and quantitative indicators to assess and compare the NDCs.