The Intergovernmental Panel on Climate Change (IPCC) has since 1988 been producing the evidence base on the science, impacts and solutions to climate change. There have been many milestones along the way – producing conclusive evidence of the effect that society is having on the climate and a Nobel Prize amongst them. In March 2018, the IPCC passed another vital milestone – holding its first ever conference, the Cities and Climate Change Science Conference.

Held in Edmonton, Canada, CitiesIPCC (as it has affectionately become known) broke new ground in three important ways. First, in terms of how the IPCC functions. Rather than gathering existing research to review, CitiesIPCC has sought to develop an agenda and generate new thinking, work and action. Second, CitiesIPCC deliberately moves away from the convention within the IPCC of considering only peer-reviewed academic research as the basis for relevant knowledge by including experience and knowledge from practitioners and policy-makers, and explicitly to making space for under-represented voices of women, youth and indigenous communities. Third, and perhaps most obviously, the conference provided the first coherent attempt by the IPCC to consider the urban dimension of the climate change challenge. While there have been ‘urban’ chapters within the IPCC reports over the past two assessment periods, cities have never received so much prominence in the work of the international scientific community.

Despite their position as a new kid on the climate change and cities block, it did not take long for nature-based solutions to make their presence felt. In the first few lines of his opening address, the Chair of the IPCC, Hoesung Lee, raised nature-based solutions as a critical response to challenges of climate change mitigation and adaptation. Along with colleagues from the Universities of Newcastle and Melbourne, NATURVATION organised one of two panel sessions dedicated to exploring the role of nature-based solutions as an urban response to climate change. After a series of short papers, including by our colleagues Laszlo Pinter and Bettina Wanschura, break-out groups considered what forms of data and knowledge were needed to support the development of nature-based solutions, and how collaboration between researchers, practitioners and policy-makers could be fostered. This was a recurring theme in the panel organised by our sister project, Connecting Nature, and throughout the conference there was a strong emphasis on the need for new forms of knowledge co-production to underpin the next generation of climate change and cities research.

CitiesIPCC represents a real advance for the science and policy agenda on climate change and is producing a research agenda that many will follow with interest. Yet it is not without limitations. In the rush to gain the legitimacy that global assessment processes that IPCC confer, the cities agenda risks becoming too closely tied to a particular model of science which values physical science evidence and quantified social science. There is a danger that in seeking data and evidence for policy, key questions of politics, justice and inclusion will become side-lined. As we develop our research on nature-based solutions we must be able to make the case not only for the effectiveness of different interventions, but also about the wider issues of power, inequality and urban sustainable development they are/not able to address.

Harriet Bulkeley is a Professor in the Department of Geography, Durham University and Project Co-ordinator for NATURVATION.