Battle lines drawn at IPCC plenary as timeline decision successfully delayed for the third time

The role of the Intergovernmental Panel on Climate Change (IPCC) in providing science input into the Paris Agreement and its critical five yearly Global Stocktake on progress towards meeting this Agreement’s 1.5°C limit and many other issues, is under challenge.

The first Global Stocktake that concluded in 2023 expressly invited the IPCC to “consider how best to align its work with the second and subsequent global stocktakes” and to “provide relevant and timely information for the next global stocktake”. There are now attempts to turn back the clock on this.

For the next IPCC assessment, its seventh (AR7), to have full input into the second Global Stocktake, its Working Group reports would need to be published before the end of the stocktake in 2028.

The consequences of a failure to align the IPCC AR7 outputs with the second Global Stocktake would be extremely serious, removing the IPCC from central formal consideration, and leaving open space for inputs that are not grounded in the robust IPCC assessment process and subject to consensus agreement from all governments. This would be a historic rupture in the role that the IPCC has played since 1990 and a major victory for fossil fuel interests who have long fought to weaken IPCC assessments for the climate change process.

Such an outcome would be very damaging to the Paris Agreement at what is likely to be a most critical moment. The second Global Stocktake will be assessing where countries have got to with their first round of commitments, how far they are away from the Paris Agreement’s 1.5°C limit and what needs to be done to close the gap.

These issues came to a head at the IPCC’s Sixty-Second Plenary, which concluded in Hangzhou, China on Saturday the 1st of March.

Whilst progress was made on agreeing the three Working Group outlines, the timing of when they would be completed was not agreed. The compromise reached as the session overran by more than a day means that the Working Groups can go forward and begin to recruit authors, but the timeline decision has been kicked down the road to the next plenary.

Why does the IPCC matter for the second Global Stocktake?

The first Global Stocktake concluded in 2023 at COP28 in the United Arab Emirates. Its findings of insufficient progress towards the goals of the Paris Agreement, in particular its 1.5°C limit, drew heavily on the ‘best available science’, which is synonymous with IPCC assessments. It helped provide the basis for the text in the stocktake outcome that countries should put forward 1.5°C aligned NDCs by COP30 in 2025.

It also paved the way for the energy package in the stocktake, notably paragraph 28 that spelt out new commitments to triple the installation of renewable energy by 2030, double energy efficiency, and transition away from fossil fuels (the first commitment on fossil fuels from a climate COP).

IPCC assessments have a history of providing the evidence-base for ambitious multilateral decisions. The IPCC First Assessment Report in 1990 helped to kick off the entire climate convention process. Its Fifth Assessment Report gave a major push to the adoption of the Paris Agreement in 2015.

It is no secret that many countries with fossil fuel interests fought unsuccessfully to keep the conclusions of the IPCC out of the first Global Stocktake. Despite this, progressive governments spanning developed and developing countries landed text in the first Global Stocktake to explicitly invite the IPCC to consider ensuring that its products would be ready for the second.

Since then, there has been a diplomatic battle over the timing of the conclusion of the Seventh Assessment so that it can provide input into the stocktake cycle (as future stocktakes will also be deprived of up to date science from the IPCC if the cycles aren’t aligned).

Timing is everything

Ahead of this plenary, the IPCC’s Bureau, led by Chair Prof. Jim Skea, tried to head off any surprises by coming to the meeting with a timeline proposal by the Co-chairs on behalf of each Working Group Bureau that would see all three Working Group reports approved in 2028, in time before the closure of the second Global Stocktake at COP33.

The previous two IPCC sessions, held in Istanbul and in Sofia in 2024, were supposed to have agreed a timeline, so this is now the third session in which this issue has failed to find an agreement.

In the Bureau’s proposal, the Working Group I report (WGI) on the physical science of climate change would just be ready in time for the mid-year climate negotiations in Bonn in June of 2028 – the likely deadline for the technical phase of second Global Stocktake, which is still being discussed under the UNFCCC. The second and third Working Groups (WGII and WGIII), focusing on impacts, risks and adaptation, and mitigation would not meet this mid-June deadline, but the proposed late June and July/August approval sessions could still allow for its consideration by negotiators, as a “critical input”, as long they were still published well-ahead of COP33.

The vast majority of governments in developed economies and in the developing world publicly supported this plan in statements ahead of, and during the plenary in China.

But a vocal few, namely India, Saudi Arabia and China, have been leading a forceful push back. They made their own proposal that would not allow Working Groups II and III to be published in time for the stocktake, and would even push Working Group III into 2029. This would mean that the best available science on solutions to address the climate crisis, on both adaptation and mitigation would not be available to draw on in the second Global Stocktake conclusions.

Experts from around the world at the AR7 Scoping meeting in December 2024, and governments, in their deliberations at IPCC-62, took great care in ensuring that the chapter outlines of Working Groups I, II, and III, which were agreed in Hangzhou, would be built on the latest scientific developments and reflective of national priorities and information needs.

This includes global temperature and emissions pathways, impacts and risks at different levels of global warming including 1.5°C, adaptation and its barriers and limits, ample regional information including for vulnerable regions of LDCs and SIDS, finance for adaptation, loss and damage responses, and mitigation, global emissions reductions benchmarks, mitigation solutions across sectors, equity and justice, and an assessment of interventions such as solar radiation modification (SRM) including the risks of such dangerous technologies.

Failing to have Working Groups II and III inform the Global Stocktake would mean that this carefully assessed science, reflective of all countries’ priorities, would be lost to the second Global Stocktake conclusion.

Tactics for delay and a false narrative

The IPCC Bureau made it clear in the agenda for the plenary that the timeline issue would only be discussed once all Working Group outlines were dealt with to head off the possibility that there would be a tit for tat between areas of focus in the report and timeline outcomes.

Right from the outset of IPCC-62 there were stalling tactics deployed to try and slow progress through the agenda. Repeated interventions from ‘larger developing countries’ took up a disproportionate share of the discussion space, with the Bureau beginning to manage interventions from the second day of negotiations.

Despite the preplanning and communication, the plenary ran more than a day over time, and many smaller country delegations had left, including SIDS and LDCs leaving diminished to no capacity in the room to represent their views.

Another tactic was larger developing countries claiming to speak to the needs of all developing countries, but in fact contradicting the expressed wishes of a majority of climate-vulnerable developing nations. This not only happened on the timeline issue, but on content relating to loss and damage. Palau is quoted calling out this dynamic after India, Saudi Arabia and China kept pursuing tactics to oppose the quantification of losses and damages.

Attempts to undermine the policy relevance of IPCC assessments

In addition to the timeline issue, reflections of the plenary by both members of the Bureau in their personal capacities, and country representatives note the increasing political nature of efforts by some countries including some major fossil fuel exporters to systematically remove key framing words and concepts from the definition of the content of the assessment cycles.

Dr Diane Urge-Vorsatz, a Vice-Chair of the Bureau, and Working Group Co-chair for the sixth assessment cycle commented on LinkedIn:

“It is concerning that key words that formed the backbone of previous reports, assessments that were consistent and among the most used components of ARs cycle after cycle after cycle were not accepted to be included in the outlines.

Key scientific concepts, such as policies, exPostEvaluation, scenarios, pathways, infrastructure, national and subnational [policies], lockin, maladaptation, targets, goals, NDCs, fossil fuels, subsidies, cost of inaction, UNFCCC, Paris Agreement, trade, conflict, market-based [instruments], non-state actors, electrification, policy packages, acceleration, overshoot, environmental impacts, attribution, future emission trends, among others – have been questioned and either cut or replaced in many places, many of these key words do not appear any more in the outline of one WG.

Some words, like the Paris Agreement, acceleration, pathways, that form important parts of one working group’s agreed outline, were considered as too policy prescriptive in another working group and were excluded.”

From its inception, the IPCC has focused on being policy relevant and not policy prescriptive. That means that its assessments are designed to support policy and show what the implications are of the latest science impacts and policy/mitigation work, but not to say what should be done. But even this mandate has been contested.

Dr Sonia Seneviratne, who is a Vice-Chair of Working Group I also took to Linkedin to concur with her colleague:

"Is the IPCC becoming science prescriptive? I share the important concerns highlighted by Diana Urge-Vorsatz after the approval of the outlines of three working group reports of the IPCC AR7...

...The most concerning point is the fact that previously approved language did not make it in the #AR7 outlines. While this is less a concern in Working group I it is particularly the case in the Working group II and III outlines (e.g. no words on "lock-in", "maladaptation", and "fossil fuels"). The bullets are however only indicative (except for the titles) and the scientists are free to adapt their assessment based on the latest science...

...Regarding the IPCC AR7 timeline, it is disheartening to see that it could still not be approved by the IPCC plenary. As highlighted by the IPCC bureau, the proposed schedule is consistent with past practice AND would allow delivering all three working group reports in time for the global stocktake. Many vulnerable nations including small-island states part of the IPCC plenary have highlighted that this timely delivery would be critical for them. But they were no longer there at the end of the meeting because it ran late as usual and the smaller delegations typically need to leave on time, so they could not weigh in on the final decision. This loophole of extending the meeting past its deadline and then artificially limiting the participants to the decision process due to practical concerns/funding capabilities is highly problematic in a context where consensus decisions are required (i.e. 100% approval)."

This open airing of concerns is really exceptional for the participants of a technical body that has taken great care over decades to remain apolitical, in order to preserve multilateral consensus on climate science.

The focus on the timing of work has received unprecedented attention from governments this cycle, for what has previously been a rubber stamp exercise for the IPCC Bureau’s proposal.

There is still time to fix this, but it will take a concerted, high level effort from the world community to make sure that the IPCC science is not taken out of the Paris Agreement ambition cycle, and the second Global Stocktake in 2028.