As reported in The Guardian, no major countries actually have commitments compatible with the 1.5 – 2.0 ˚C maximum target in the Paris Agreement: “When taken as benchmark by other countries, the NDCs of India, the EU, the USA and China lead to 2.6 °C, 3.2 °C, 4 °C and over 5.1 °C warmings, respectively.” Canada is among the very worst: “We find that the NDCs of Canada, China and Russia are less ambitious than their CBDR-RC hybrid allocations even under the least ambitious global emissions scenario available, with 5.1 °C of warming in 2100”.
From the beginning people have been skeptical about how serious countries are about the warming targets in the Paris Agreement, with the most optimistic believing that the agreement would be a first step toward gradually adopting compatible targets.
The Nature Communications paper is also quite interesting in its discussion of global equity and climate change, arguing that: “While not all countries use indicators that favour their equity argument in their communication, a common definition of equity is unlikely to be adopted since countries generally tend to support interpretations of distributive justice that best serve their self-interest and justify their negotiating positions”.