Assembling the IPCC’s mammoth climate change reports is challenging at the best of times. Doing it during the pandemic was much harder.
The most recent report from the Intergovernmental Panel on Climate Change (IPCC) – Climate Change 2022: Impacts, Adaptation and Vulnerability – released in late February, is the product of more than four years’ work from hundreds of scientists and bureaucrats. Assembling a report like this is ordinarily no small undertaking, but during COVID lockdowns, it’s a labour borne of late-night Zoom calls and painstaking revision.
The latest report pulls together more than 34,000 recent scientific studies on climate change, reviews them, assesses their scientific merit, and draws conclusions about where we are and where we are heading as climate change continues. It’s the Sixth Assessment Report (‘AR6’) and this particular release is from Working Group II, which looks at our vulnerability to climate change.
Initially, the 270 scientists and government delegations from around the world nominate which topics they would like to see covered in the report, after which a skeleton outline of the report is assembled by consensus.
From there, authors are recruited to the task. In assembling the authorship group, the IPCC considers representation of men, women, geographical spread, and expertise. A country that is a party to the United Nations Framework Convention on Climate Change is permitted to provide experts to contribute to a given chapter. Scientists self-nominate or are selected because of their experience. It is a prestigious role, and one with great responsibility – but one with huge demands.
Two co-chairs then take the lead in co-ordinating meetings and for check-ins for the report. The current report was chaired by Professor Hans-Otto Pörtner, a physiologist and marine biologist from the Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research in Germany, and urban biogeography specialist Professor Debra Roberts, from South Africa.
The Impacts, Adaptation and Vulnerability report consists of 18 chapters. The specialist authors assigned to a chapter coordinate their smaller group to assess the science and produce the text. Within each chapter group, a few people are assigned to check in with other chapter groups to make sure their section does not overlap, and complements the other chapters.
There are usually two ‘coordinating lead authors’ who take a leadership role in the process, while ‘lead authors’ do the bulk of the writing. ‘Contributing authors’ are called upon as necessary. They’re people with specific technical expertise who write a section on their area. Contributing authors don’t see the entire chapter – they just provide their input as requested.
“It’s very invigorating, very exciting to be involved in, doing an assessment,” says Professor Philip Boyd, a marine biogeochemist at the Institute for Marine and Antarctic Studies, University of Tasmania, and a lead author of the report’s chapter three. “The flip side of that is that obviously it’s working in a large group – it’s doing it by committee, which is never ideal.
“But it’s a very exhilarating sort of interface, because in Working Group II, we actually have this sort of interplay between the natural and the built environments, so you’re actually then learning a new lexicon during these meetings. You go to breakout sessions on behalf of your chapter and you’re hearing from social sciences, and other folks like that. So you get a different sort of lens to look at things.”
The authors are heavily engaged on the project for the full four-plus years it takes to produce the report, and given the timing COVID-19 has naturally resulted in some extra challenges in making this report.
Ordinarily, the authors meet in person several times to work on the report and overcome any sticking points. In the early part of the cycle Working Group II met in Durban, South Africa, Faro, Portugal and Kathmandu, Nepal – but in the final two years of the assessment cycle, international travel has not been possible for many countries. Instead, the group, like those in so many other industries, has had to learn to work remotely.
“We managed to have first three LAMs – lead author meetings – in person,” says Boyd. “And the contrast to the final (fourth) one – it was a two-week electronic meeting, which given all the different time zones and issues really was very challenging, even with us getting a bit better with video conferencing. That’s been challenging and it’s actually dragged out the AR6 cycle a bit longer.”
The final step in the assembly of the report is the hardest. The thousands of pages of the report are condensed into a Summary for Policymakers (SPM). The summary is created with the expectation that policymakers might not have a chance to read the full report, so it needs to be an accurate reflection of the underlying report. It also needs a clear connection – ‘line of sight’ – to the full report, so that policymakers can delve deeper into a topic if they need to.
Around 50 scientists from the initial group are co-opted to the summary group. Then, in an online meeting of authors and government delegations lasting two weeks, each sentence of the Summary for Policymakers is read out and agreed to by consensus. When consensus is reached, the chair bangs a gavel and the sentence is turned green to signify its acceptance.
“I wasn’t involved with [the summary group], but I think that was actually slightly easier this time,” says Boyd. “Typically, when they have that as an in-person event, everyone runs out of everything, you know – there’s no food left, there’s no water left. Everyone starts to get hangry – which is never a good sort of baseline to try and build consensus.
“At least when people were home, they could actually raid the fridge or get pizza in or whatever to keep them going, because typically these things go on for many hours.”
Fridge access notwithstanding, recreating the process of a live plenary over Zoom has significant challenges. There might be a split second between someone raising their hand for an objection and the gavel coming down. The split second might be a result of computer lag and so an IPCC legal officer needs to adjudicate on whether to hear the objection.
COVID has also made production of the report more difficult in the same way that COVID has challenged everyone. People becoming unwell or juggling caring responsibilities, or even professionals being pulled into COVID response teams, has pulled focus from production of the report.
Even through the ravages of COVID, climate change remains a growing problem, and the report team remained committed to the task. The process is a co-production between a large group of government and scientific experts. Through many rounds of iterations, the report has been questioned, commented on, reviewed and refined. More than 62,000 review comments were received, with a single chapter receiving as many as 8,000 comments in a review round, each of which must be addressed.
“It isn’t something on which you spend maybe an hour or two a week,” explains Boyd. “The biggest challenge is to try and keep things fresh. Sometimes, you’ll be working on a draft intensively and you’re at the stage where you can’t see the wood for the trees. And then suddenly you get dumped with all of these comments.
“Each of those comments has to be addressed in this ginormous spinnaker of a spreadsheet. If you’re really unlucky, personally, you might have to deal with 400 or 500 out of those 8,000 or 9,000 – because it just depends what parts of the chapter are seen as most contentious.”
Working Group I released its contribution to the Sixth Assessment Report on 9 August 2021. It assessed the scientific evidence for whether climate change is caused by humans (it is). Working Group III, looking at ways to prevent climate change from becoming worse, will release its report at the beginning of April.
Having worked on both the AR5 and AR6, Boyd’s not sure he’s got the time – given other international commitments – and stamina to do it all again.
“It’s a prestigious gig, and it’s also eye opening,” he says. “You look at things slightly differently after having been involved. And it’s also useful to disseminate that to some of the early career people coming up, to sort of explain that five years of their work might make it in the IPCC report as a phrase, or if they’re very lucky as a sentence. That’s because it’s an assessment and typically, we’ll look at thousands of pieces of literature.”
This article was published in partnership with 360info.org
Kathryn Bowen is Professor – Climate, Environment and Global Health, and deputy director, Melbourne Climate Futures at University of Melbourne. She is a lead author on chapter seven of the IPCC Sixth Assessment Report and a lead author on the Summary for Policymakers.