On the occasion of the French state visit to China on November 2, President Xi Jinping and President François Hollande released a joint statement on climate change, which lends strong support to a comprehensive mechanism in the Paris agreement to increase ambition over time and stay below the 2°C global temperature limit.
After the G7 declaration in June, the US-China joint statement and the conclusions of the meeting of 44 Heads of State and Leaders at the UN General Assembly in September, this new announcement once again “underscore(s) the importance of formulating 2050 national low-carbon development strategies”.
As demonstrated by the Deep Decarbonization Pathway Project, such long-term pathways are indispensable for ensuring that short-term actions are consistent with the transformations required to achieve deep decarbonization by mid-century. They are also instrumental for supporting stakeholder engagement with business, civil society, and other actors in each country. At the international level, they can help identify areas of cooperation, notably on R&D, and build trust in other countries’ commitments to reduce emissions. As a consequence, long-term pathways can help foster implementation and strengthen the ambition of country contributions to climate action over time.
The China-France joint statement adds two historic steps forward for an effective ambition mechanism in the Paris agreement. Indeed, they underline the importance of “an enhanced transparency system to build mutual trust and confidence and promote effective implementation” and of the inclusion of “provisions for Parties to formulate, communicate, implement and regularly update their nationally determined contributions. They support taking stock every five years and in a comprehensive manner of overall progress made towards reaching the agreed long-term goals. The results of this stocktake will inform Parties in regularly enhancing their actions in a nationally determined manner”.
These elements – transparency and regular cycles with an enhancing mechanism – are two key mechanisms to progressively bring action in line with the below 2C target. In this process of regular revision, developing deep decarbonization pathways can have two important functions. Firstly, it can improve the transparency and credibility of action, by showing the key concrete transformations that are required for countries to reach their climate actions. Secondly, they can provide the basis of each new contribution, ensuring that these contributions take into account the need for deep transformation in the long-term. The Paris Agreement can lay the basis for this mechanism of transparency and regular cycles, and deep decarbonization pathways developed at the national level can provide the motor.
 See notably the joint IDDRI-NCSC paper: Regular review and rounds of collective cction and national contributions in the 2015 climate agreement: a proposal