From NDC to national long-term low greenhouse gas emission development strategies compatible with a 2 °C target

Given the lack of collective ambition resulting from the Nationally Determined Contributions (NDCs) to the objective of the Paris Agreement, countries must submit revised and more ambitious NDCs. Countries are invited to formulate longterm low greenhouse gas emission development strategies that should be designed within the context of other development goals and co-benefits. This article addresses the issues related to the evaluation of national trajectories developed in a cooperative framework aiming at collectively reaching 2°C and based on the integration of development priorities and co-benefits into national trajectories. The national decarbonization trajectories discussed in this article were developed as part of the Deep Decarbonization Pathway Project (DDPP) by the 16 major GHG emitting countries. These 16 bottom-up decarbonization strategies are implemented in the POLES model, a partial equilibrium model of the global energy sector, which is an appropriate tool to provide a harmonized contextual framework for assessing these trajectories. The results make it possible to evaluate the gap between, on the one hand, national DDPP trajectories and NDCs and, on the other hand, national DDPP trajectories and a scenario resulting from a minimization of abatement costs. They allow to feed a discussion on the development of NDCs and the move away from national trajectories of trajectories minimizing the overall reduction cost and produced with integrated assessment models.