Established 35 years ago, the Intergovernmental Panel on Climate Change (IPCC) is today a leading scientific authority on climate change, and its conclusions have inspired much action and activism on the issue. It is generally expected that the IPCC will educate and convince people about the reality of climate change and the need for urgent action. Yet the way the organisation works reveals that it is less a case of educating or convincing than it is starting a dialogue on the socioeconomic implications of the climate crisis. At times, this turns out to be a dialogue of the deaf and shows that a consensus on science does not necessarily improve decision-making.

The past few years have seen an unprecedented campaign by scientists and civil society organisations to firmly place climate on the political agenda. In August 2021, Swiss citizen Guillermo Fernandez began a hunger strike after reading the IPCC’s conclusions. He demanded that the Swiss government receive an in-depth briefing on climate change and biodiversity loss – a demand that was eventually met. In June 2022, scientists from the IPCC and the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES) said that they would be willing to give French members of parliament a crash course on climate change and biodiversity loss. Installed in a tent just a short walk from the National Assembly, the scientists took turns to speak over three days and met over 150 MPs — some 27 per cent of the lower chamber. Over the same period, The Ecological Awakening collective put up spoof fast-food adverts in train and metro stations announcing “On the menu tonight: IPCC report!”.

When I started my PhD in 2013, the context was very different. A few years earlier, in 2009, the IPCC was under fire from critics after they discovered mistakes in its fourth assessment report. The most glaring one warned of the possible disappearance of Himalayan glaciers by 2035. The year given was wrong — the result of a typo in one of the documents cited by the IPCC — and should have read 2350. These errors emerged at a time when climatologists were already in a tricky situation, having been falsely accused of exaggerating the degree of global warming in the so-called Climategate affair. Such was the controversy that in 2010 the IPCC decided to undertake root and branch reform of its procedures to re-establish its authority and regain the public’s trust.

Of course, the IPCC’s authority was not built overnight and has been questioned on numerous occasions. The IPCC’s success as the interface between science and society is the result of a long process punctuated by controversies and hard-learnt lessons, which I describe in GIEC. La voix du climat (IPCC: the Climate’s Voice), published by Presses de Sciences Po in 2022. The organisation’s history shows just how interconnected science and climate policy is. It also shows that the challenges the IPCC has faced have less to do with a lack of information and more to do with disagreements over how to interpret scientific findings and turn them into policy.

Success against the odds

The creation of the IPCC in 1988 was highly politicised: on one side were scientists, who believed there was enough evidence to establish an international convention on the climate; on the other was the United States, who opposed this idea, proposing instead that agreement first be reached on “the facts”. Fearing the economic impact of potential greenhouse gas emissions regulation, the United States — the biggest emitter at the time — agreed to the creation of the IPCC but sought to maintain its control over the matter by insisting the IPCC be intergovernmental, in other words, governed by its member states. The organisation’s work would underpin the United Nations Framework Convention on Climate Change (UNFCCC) in 1992 and serve as the basis for the Conference of the Parties’ (COP) activities.

Being both scientific and intergovernmental in nature, the IPCC quickly became a one-of-a-kind organisation. As a “boundary organisation”, it institutionalises dialogue between scientists and representatives of the world’s nations on one of the most technical issues of our time. It also enables both communities, which in reality comprise multiple viewpoints and interests, to coordinate with one another. IPCC meetings provide an opportunity for different scientific communities to marry their different approaches, interdisciplinarity lying at the heart of its three working groups: Working Group I on the physical science basis of climate change; Working Group II on climate change impacts, adaptation, and vulnerability; and Working Group III on mitigation of climate change. They also provide a space for governments to agree on the state of knowledge on climate change, its consequences, and solutions for tackling it. Once a consensus has been reached, it is hard to challenge in international arenas such as the UNFCCC.

The challenges the IPCC has faced have less to do with a lack of information, and more to do with disagreements over how to interpret scientific findings and turn them into policy.

But this dialogue between different scientific and political communities is not straightforward. Firstly, because it requires striking a balance between different viewpoints, which is difficult in practice. For example, the IPCC has long been dominated by the natural sciences, favouring a scientific and technical definition of climate change. Climatologists believed it was crucial to convince people of the reality of climate change by remaining clear and informative in the hope that, once convinced, decision-makers would turn this knowledge into action. Having been criticised for “depoliticising” the climate, the IPCC has tried to involve social scientists more and better integrate socioeconomic, political, and ethical analyses of the climate crisis, which are essential for understanding climate (in)action. For the social sciences, the problem is less the lack of information on climate change than it is the path dependencies that hamper the transition towards a low-carbon society and the powerful vested interests who stand to lose from us kicking our addiction to fossil fuels.

Just like their epistemic diversity, the geographic diversity of IPCC experts has also long been lacking, with scientists generally hailing from developed countries or affiliated with institutions based in these countries, especially the United States and the United Kingdom. Despite efforts made by the organisation to increase their participation (these asymmetries being structural and existing outside of the IPCC), academics from the Global South only represent a third of contributors to the Sixth Assessment Report. This means that their viewpoints are less well reflected in the reports. For example, it was not until the IPCC’s Third Assessment Report (2001) that, at the urging of scientists from the Global South, the organisation seriously addressed the question of adapting to climate change, a key issue for countries in the developing world, who are hit hardest. Experts from the Global South have also criticised the IPCC for not placing enough emphasis on equity and climate justice.

The dialogue between different scientific and political communities becomes even trickier when it comes to the main conclusions of the IPCC assessments. While IPCC reports run into thousands of pages, their political summaries — the famous Summaries for Policymakers — only number 30 odd pages. This summarisation and translation process inevitably involves making choices, simplifying statements, and agreeing on the most “relevant” conclusions for decision-makers. This exercise has always been controversial because each author or delegate has their own idea of what is important to communicate to policymakers.

The idea that a consensus could return discussions to a rational basis is illusory — in the end, politics always rears its head again, even at the IPCC.

Some want to focus on the most robust conclusions, while others believe it is more important to communicate the extent of (un)certainty on issues such as low-probability and high-impact extreme events. On the question of climate change mitigation, some want to prioritise incremental changes and cheap technical solutions, while others believe that more radical solutions are necessary. Producing Summaries for Policymakers is therefore a delicate exercise in diplomacy that must allow a compromise to be found between a myriad of voices. It’s a matter of offering a “balanced” assessment of the different views of the climate crisis and the different interests of IPCC member states, from the most sceptical to the most convinced.

Overall, the IPCC’s conclusions are the result of a summarisation and negotiation process and reflect different dynamics and viewpoints. Its legitimacy does not so much lie in its ability to convince as it does in facilitating dialogue between different stakeholders based on a process seen to be credible, legitimate and reflective of everybody’s interests. The IPCC’s deliberations are therefore political, because climate change is an intrinsically (geo)political problem. The idea that a consensus could return discussions to a rational basis is illusory — in the end, politics always rears its head again, even at the IPCC.

That said, there’s very little sign of politics in its final reports, because finding universal agreement often means decontextualising and depoliticising the climate issue. Reaching a consensus frequently involves smoothing the edges and avoiding thorny subjects. Summaries generally report the degree of increase in atmospheric greenhouse gas concentrations caused by human activities, as well as the increase in the frequency of impacts around the world. They also remind us that we are not on track to limit warming to 1.5°C, or even 2°C.

Nevertheless, they end on an optimistic note by outlining the many tools available. Report after report, press conference after press conference, this message becomes more and more strident, but changes very little. Damning as it may be, the message is politically inoffensive because it deals in generalities that neither upset nor blame anyone. Rather, it justifies the continuation of negotiations.

The new challenges facing the IPCC

The IPCC has never really been about convincing or educating governments on the reality of climate change, but debating the socioeconomic implications of this reality for collective action. What are presented as matters of fact become matters of concern, dissected from every angle by the organisation’s authors and delegates. Although the reality of climate change is rarely questioned these days, how it should be tackled is increasingly controversial, especially in deliberations within Working Groups II and III.

Damning as it may be, the IPCC’s message is politically inoffensive because it deals in generalities that neither upset nor blame anyone. Rather, it justifies the continuation of negotiations.

The more debate shifts towards assessing adaptation and mitigation policies, the more the IPCC’s structure and workings will become obsolete. Because climate science and policy are ever more polycentric, the IPCC must open up to new groups of stakeholders, not just scientific experts and delegates from UNFCCC parties. Many observers are calling for better representation of civil society, industry professionals, local authorities, indigenous communities, ordinary citizens, women and young people. As a result, the IPCC will have to rethink its role in climate governance.

Since its creation, the organisation has presented itself as neutral with the mantra “policy-relevant and yet policy-neutral, never policy-prescriptive”. But by limiting the debate to scientific experts and States only, and by depoliticising the issue of the climate, it helps maintain the status quo and ends up sending a political message that is powerful yet untenable in the current context: the climate crisis can keep being managed by a technocratic elite.

Today, ahead of the seventh assessment cycle, simply informing is no longer enough. Neither is satisfying the demands of every government. To escape the straightjacket of depoliticising and dehumanising multilateralism, the IPCC (not just its authors but delegates too) could collaborate more with civil society organisations that support its work. This could create space for new forms of action. In 2022, for example, Scientist Rebellion — an offshoot of Extinction Rebellion — leaked a draft of the Working Group III Summary for Policymakers, fearing that its contents would be watered down once submitted to governments for approval. There have also been instances of authors threatening to abandon the process, going on strikes or calling out the behaviour of certain states — practices that are strongly discouraged today, if not banned outright.

The IPCC’s authority has historically rested on its ability to provide a space for negotiation between its member states. Perhaps the time has come to establish a wider dialogue and forge new alliances?