The period through 2020 is critical to increase ambition. The 2018 Facilitative Dialogue will play a key role. The IPCC Special Report on 1.5°C (expected September 2018) will provide important input. Before Paris, the scientific input of the First Periodical Review (FPR) and its Structured Expert Dialogue (SED) was critical.
The FPR concluded that the 2°C limit as a line of defence should be pushed lower. Additionally, the world is not on track to achieve this goal. In other words: meaningful mitigation measures must urgently be scaled up. In Paris, Parties used this input and took the important decision to strengthen the global goal to pursue efforts to limit warming to 1.5°C compared to preindustrial levels.
Periodic reviews and expert dialogues need to be repeated regularly under the Paris Agreement. We need to start with the Second Periodical Review (SPR) and its dialogue in 2017, or in May 2018 at the latest. A further session should be organised in October 2018 to summarise the content of IPCC Special Report on 1.5°C to inform the Facilitative Dialogue in 2018. Key questions here will be: What path do current NDCs put us on; and how far is that from achieving the Paris goals?
The SPR has to examine the adequacy of the long-term goal of the Convention and how far we are from achieving it. This should be in sync with the IPCC process for AR6. The SPR should finish its work in 2022 or 2023 so that it can inform the Global Stocktake in 2023 with the latest science.