Read the draft summary for policymakers of the most important climate science report of the year, on the challenge of holding global warming to 1.5C

By Megan Darby

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What are the impacts of 1.5C global warming, compared to 2C? What would it take to limit temperature rise to that level? What are the trade-offs with sustainable development goals?

These are the questions to be addressed by the Intergovernmental Panel on Climate Change (IPCC) in a special report due to be finalised in September 2018.

Climate Home News has obtained a draft of the summary for policymakers, which sifts through the peer-reviewed literature for answers.

The draft report, which was publicly available on the US federal register over the past month, is open to review by experts and governments until 25 February on the IPCC website. Relevant studies published in journals by 15 May may be included in the final version and modify its conclusions.

After media reports on the summary in January, the IPCC released a statement.

Draft reports are provided to reviewers as working documents. They are not intended for public distribution, and must not be quoted or cited for the following reasons: – Firstly, the text can change substantially between the Second Order Draft and the final version once the report’s authors have carefully considered every individual government and expert review comment. For instance, the First Order Draft of this report received 12,895 comments from nearly 500 expert reviewers. Like any work in progress, it is important to respect the authors and give them the time and space to finish writing before making the work public. – Secondly, the Second Order Draft is based on scientific literature published or submitted for publication before 1 November 2017. Newly published scientific evidence highlighted by reviewers can still be taken into account between the Second Order Draft and the final version of the report, as long as it is accepted for publication in a journal before 15 May 2018. Drafts of the report are, therefore, collective works in progress that do not necessarily represent the IPCC’s final assessment of the state of knowledge. The IPCC is committed to an open, robust and transparent assessment process. In each stage of review, the Working Groups actively seek the collaboration of researchers and practitioners across a broad range of expertise. As with the normal practice of peer review, this process is designed to make the report more accurate, comprehensive and objective.

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IPCC special report on 1.5C – draft summary for policymakers by Megan Darby on Scribd