By Bethan Davies (Lead Author, IPCC AR7, Chapter 2)
It is a hot and humid day in June 2026 – breaking many records, in fact, for the warmest June day in the UK on record. An apposite day, it seems, to finalise my first draft of my chapter section of the IPCC First Order Draft.
LAM1
It’s been a long haul, and I have never written anything quite like this report. We started in earnest in December 2025, when we met shortly before Christmas in a wintry Paris at Lead Author Meeting (LAM) 1. We were cloistered together in a hotel, with a conference venue on site, and the long days meant that this was pretty much all we saw of the Christmas decorations of Paris. At this hotel we met and got to know our chapter co-authors, and thrashed out a rough outline and structure for the IPCC Assessment Report 7 Zero Order Draft.
Upon checking in, we received our very own weighty hard copy of the IPCC Assessment Report (AR) 6 – just in case we weren’t quite daunted enough by the task ahead of us.
It was a challenge to do this. Not only do we have the 20-odd Lead Authors, three Coordinating Lead Authors and three early career Chapter Scientists in our own chapter, amongst whom we need to reach agreement, but authors in many other chapters. In previous reports, chapters were thematically organised, with cryosphere scientists for example mostly being in Chapter 9 of IPCC AR6. This time, the chapters are organised rather differently, and so the different components of the climate such as the cryosphere are split up amongst many chapters.
Meetings upon meetings
In practice, in Paris, this meant attending many meetings; palaeo meetings, where the role of palaeo science in the report was discussed; and also meetings focused in turn on the cryosphere, ocean and sea level. All our chapter authors were busy in ‘Break out groups’ (BOGS) all week, and then periodically reporting back to our chapter team.
Amongst all of this, we were busy getting to know each other, and working out how to work best as a team. We were working out each others’ areas of expertise, working out who would lead different sections and who would work across multiple sections, and who would lead various Cross Chapter Boxes (CCBs – the IPCC is full of acronyms). It was interesting to get to know such a diverse international group of people. Our chapter team has people from many different nationalities, but all are eminent experts in their fields. Some have worked on IPCC reports before, but most of us were new.
It was so important to come together and to do this in person. Working across so many groups would not be possible online. You can’t catch people quickly at coffee, or build an effective working relationship, online.
A highlight for me was our one night off when we explored Paris together, enjoyed hot wine at a Christmas market, and ate dinner together.
All credit goes to our capable and friendly Coordinating Lead Authors (CLAs) (centre in the photograph above), who led our little team of writers with calm efficiency, making sure we achieved our goals for the week.
Zero Order Draft
By the end of the week, we had a rough chapter outline, with detailed bullet points under each section heading and sub-section heading. We then went away and fleshed this out further over the next few weeks, adding in key references and details.
This final compiled “Zero Order Draft” (ZOD) was then submitted to TSU (Technical Support Unit), compiled, and then circulated to and reviewed by all authors (and a few invited former authors), who were all invited to comment on other chapters, and to raise points about omission, duplication or key ideas. This was an informal, internal review, not part of the formal IPCC review process.
LAM2
This brought us to the Spring, and to Lead Author Meeting (LAM) 2 in Santiago, Chile. By April 2026 we had had a chance to review the comments from colleagues on the ZOD, and were looking forward to getting started on the First Order Draft (the ‘FOD’).
Once again we were all cloistered in a hotel, with daily buses taking us to the venue. We were kindly hosted by Pontifica Universidad Catolica de Chile at one of their campuses.
This was another intense meeting, with long, busy days and no time to explore the city. We were again busy in cross-chapter meetings, break out groups and chapter meetings, to narrow down and put more detail into our chapter outline. We finalised the writing style, discussed the nuts and bolts of how to do an ‘assessment’, and as in LAM1, received many training sessions from the experienced Technical Support Unit (TSU, to whom we are ever indebted).
Again, for me, a highlight was our one evening of ‘chapter social time’, which involved a walk and a dinner together. It was great to carry on building relationships and getting to know each other on a more personal level.
I decided to make the meeting a little more exciting by losing my phone during the week – just to add some intensity!
By the end of the busy week, we were primed and ready to start writing the ‘First Order Draft’. We were devolved into mini teams, with different people leading particular sections. Other people are leading cross-chapter boxes, or getting involved in the Atlas, or contributing to many sections both within our chapter and other chapters. Our CLAs oversaw the process, guided the chapter team, and set the agendas.
Contributing Authors
A major part of LAM2 was to identify areas where the chapter author team lacked expertise. There are, of course, many. We spent a lot of time coordinating with authors in other chapters, and asking particular people with the requisite expertise to serve as ‘Contributing Authors’ in our chapter. Many of us are also serving as Contributing Authors in other chapters. This helps to ensure continuity between chapters, to ensure that expertise is best used wherever needed, and avoid duplication or a confusing narrative.
Where we had no relevant expertise within the IPCC Working Group I author team, we considered external authors to invite as Contributing Authors, with a mind to balancing gender and nationality, but these are limited in number. We asked authors first who were nominated but not selected as IPCC authors, which was a new process for this year.
If you’re interested in serving as an IPCC Contributing Author, it therefore helps to be nominated! Nominations are submitted by government Focal Points, accredited observer organizations or IPCC Bureau members in the beginning of an IPCC cycle (see IPCC post and practical information here). More information on IPCC roles here.
Drafting the FOD
We all left Santiago tired, but excited, and ready for the next challenge – actually writing the report. This was a major, full-time job that personally occupied me fully, to the extent that I ignored all other tasks, between April and June. I was fortunate that my university had awarded me a research sabbatical that allowed me to concentrate on this important report. My section alone cites hundreds of peer reviewed papers, all of which (and many more!) were carefully read and considered. We reviewed the strength of the evidence, the degree of agreement amongst independent studies, and the changes since AR6.
Throughout this period, we had meetings, meetings, meetings, all online. Meetings with the CLAs to see progress in my section. Meetings with the Land Ice, Sea Ice, Sea Level, Permafrost or Snow authors in other chapters. Meetings with the Contributing Authors or Lead Authors contributing to my section. Meetings also often at inconvenient times, late at night or early in the morning, to account for the different time zones in which we are all working.
I’ve never written anything like this. I’ve written over 100 peer-reviewed publications, but this was different. The vast majority of my writing pieces are team efforts, but rarely such large and involved teams (to be honest, it is normally just a small group who do most of the work, even in big author teams). When writing a paper, or a book chapter, you rarely have to coordinate with authors in other chapters, or this is done by the book editor. Rarely is one part of the story in your section but one part in someone else’s chapter, meaning you have to ensure that the narrative is coherent. Like I said, an intense time.
I also do not feel that I have ever written anything so important. Something that hopefully will make people sit up and take notice. As I sit here in my hot house, on the warmest June day ever in the UK, I have to hope that people will pay attention.
Sometimes it is difficult to remain positive – reading our executive summary today, I could feel the frustration building. Climate change is affecting every part of our Earth system, and it’s not slowing down. People will die in this heat wave. I hope we can learn to adapt, and to change our ways collectively as a species, before too many more die.
Looking forward
Of course, it is not over. This is only the First Order Draft. Our hard working and talented chapter scientists tomorrow will compile all the individual section documents, collectively written by many people, into one master document, written by even more. That will be submitted to TSU and then reviewed internally by the IPCC internal author team. We’ll then get a chance to amend and update and edit it following those comments.
External review
Then the big review – the FOD will go out to expert review this summer. The weight of the IPCC report comes not from the authors, who play only the smallest of roles. It comes from the experts whose papers we cite, and the experts who carefully and in detail review what we have written. We are grateful to them for their expertise and their time. Expert colleagues should keep an eye out for the opening of the IPCC registration platform to apply as an external reviewer. The review will run from August 10th to October 2nd 2026, and people can register until late September to review the FOD.
We are expecting thousands of comments from the expert review process, which will take place over this summer. We’ll be dealing with them at LAM3 in November 2026, so that is something to look forward to. And then there will be a Second Order Draft, and another round of reviews. I know that everyone has put their heart and soul into this report, reading hundreds and hundreds of peer-reviewed papers, speaking to experts, and making sure every statement is carefully and strongly justified. Remember that none of us are getting paid for this work – and I have had to set aside any other research work for the last few months.
I have enjoyed writing this report, and meeting all these interesting people, and learning so much about different components of the climate system. My knowledge is better, and wider, than it was before I undertook this process. And I am glad that I have been a part of it.