Long-term strategies in the Paris Agreement create a need for extensive and streamlined modeling activities and scenarios development.
Long-term strategies, introduced in Article 4.19 of the Paris Agreement,1 are a key to aligning emissions reductions with the global goal of “well below 2°C.” These strategies are meant both to ensure that the regular revision of countries’ short-term emissions targets in Nationally Determined Contributions (NDCs) is consistent with the long-term climate objective, and to support identification of collective priorities for knowledge sharing and international cooperation in the stocktaking dialogues. The nonbinding nature of the long-term strategies should help catalyze the exchange between alternative visions of long-term, low-emissions development. Different sets of policies and measures can be compatible with the Paris objectives, depending on the assumptions about the future development of socioeconomic, technical, and political systems. As long as these assumptions are internally consistent, the alternative visions of the future can conform with options available to decision-makers. Creating a space to incentivize the elaboration of these alternative possible futures and to structure the dialogue among them can broaden the possibilities in an open-mindset approach. This is different from the NDC process, a formal, binding contribution by Parties to other countries that will involve political negotiations and is therefore less suited to an open and transparent dialogue beyond administration and high-level policymakers. The complementarity between NDCs and long-term strategies lies in the capacity to seize the opportunity created by the latter to explore dimensions that can inform the design of NDCs, like different options for ambitious mitigation and associated complex and politically sensitive issues, like the articulation with development objectives. The relevance of this approach in turn depends on the availability of research inputs that offer transformational visions of emissions drivers in different countries, taking into account their specific socioeconomic, technical, and political circumstances.