Prior to the Paris Agreement, much research focussed on holding warming to 2 °C above pre-industrial levels. With the inclusion of an aspiration to limit warming to 1.5 °C in the Agreement's text, and a 2018 deadline for an IPCC special report on the subject, the academic community is having to coordinate to modify the focus of the research agenda.
To be included in the IPCC's special report, research must be submitted for publication by October 2017 and accepted by April 2018. As such, we hope to be regularly updating our dedicated 'Targeting 1.5 °C' Collection (www.nature.com/1.5Ctarget) over the coming months.
With this timeframe in mind, researchers gathered at a special conference on the 1.5 °C goal at the end of September, hosted by Oxford University's Environmental Change Institute. It was clear that reservations remained about the achievability of the goal. Nonetheless, there was a sense that scientists have a duty to try and answer policymakers' questions. Over the course of the conference, a few key themes emerged.
There was some disagreement on the precise point at which the world may blow a carbon budget commensurate with the 1.5 °C goal. Nonetheless, it's clear that time is running out for the deep decarbonization that will be necessary if policymakers are to stand a chance of fulfilling their aspirations. That likely requires some fundamental lifestyle changes; an idea that many governments have so far found difficult to sell. There were also concerns that the emissions reductions required to put the world on a path to 1.5 °C rather than 2 °C could potentially obstruct efforts on related social goals, such as alleviating poverty or encouraging sustainable development. Exploring how an additional 0.5 °C of warming could impact vulnerable countries, compared to the impacts of mitigating this, remains a research priority. This may have to be achieved through modifications to current models, with the IPCC's timetable constraining researchers' ability to conduct entirely new research.
The 1.5 °C goal — and the idea of producing a dedicated IPCC report on the topic — continues to be controversial. But the research community is mobilizing to try to provide a solid scientific foundation for policy discussions around this ambitious aspiration.