The IPCC’s priorities for the next six years: 1.5C, oceans, cities and food security

§ ‘In good time’

As in previous years, the next big IPCC report – the sixth assessment report (AR6) – will be released in three stages, the IPCC chair, Dr Hoesung Lee, confirmed today.

The three working groups – broadly covering the physical science, adaptation, and mitigation – will be published between 2020 and 2021. The synthesis report, which is meant to link all three working groups into one concise storyline, will be published in 2022.

Lee told a press conference in Nairobi this morning (see video below) the timing of the synthesis report is deliberate, so that it would be “in good time” for the global stocktake that nations will be undertaking in 2023, as agreed at COP21 in December.

The IPCC will also consider publishing its big reports every five years, rather than every six or seven. Youba Sokona, the IPCC vice-chair, said the panel was “very much in recognition” of the benefits of better aligning with the UNFCCC’s timeline for global stocktaking.

§ A focus on 1.5C

Out of a list of nearly 30 suggestions, the IPCC chose to do three special reports.

The first will be on the impacts of 1.5C warming – a late addition to the list and a specific “invitation” by the UNFCCC, after language about efforts “to pursue 1.5C” made it into the final text of the Paris Agreement. Lee told the press conference today:

The question of how to limit warming to 1.5C has been gaining a lot of media attention, especially its almost guaranteed reliance on ‘negative emissions’ technologies.

Nevertheless, the IPCC seemed reluctant this morning to speculate on what a special report on 1.5C might entail, what its main purpose will be, or how much new research will be required.

All Lee would give away was that the report would be produced “as early as possible” (aiming for 2018) and that a detailed outline will be fleshed out “in the coming months”.

But scientists have certainly been spurred into action, said Dr Debra Roberts, co-chair of Working Group Two, telling journalists the scientific community was “already mobilising”. Indeed, an international conference at Oxford University in September will see scientists, policymakers, businesses and civil society gather to discuss the challenge of meeting the 1.5C goal, a level of ambition which the organisers say “has caught the world by surprise”.

It’s worth noting, however, that by the time AR6 is published, the current pace of emissions will mean the IPCC’s carbon budget to stay below 1.5C will essentially have been exhausted, as the graphic below shows (Note: figures  based on 2014 emissions).

§ Oceans and cryosphere

Monaco put it one of the earliest requests for a special report on oceans, to “gather in a sole document all the scientific knowledge related to the role of the ocean in the climate system and climate change impacts”.

Before the meeting in Nairobi, the co-chairs of each working group commented on each of the proposed topics for special reports, to help the panel decide which was most urgently needed.

They acknowledged that while oceans, the cryosphere and sea level rise were covered in detail as separate issues in AR5, linking them more explicitly would help policymakers better understand extreme events and consequences of climate change for ecosystems.

The contributions of the oceans to mitigation were also “poorly addressed” in AR5, noted the co-chairs of working group two, adding that the “magnitude of the issue and overarching implications” should make the topic a priority for a special report.

There are critical thresholds in the cryosphere that could well be passed at 1.5C, says Prof Jonathan Bamber from the University of Bristol. He tells Carbon Brief:

§ Food security

The third topic chosen for a special report combines what the co-chair of working group one, Dr Valérie Masson-Delmotte, describes as “several land surface issues”.

IPCC decides to prepare 3 special reports for AR6 : 1.5°C (Paris agreement), oceans and cryosphere, and several land surface issues

— Val. Masson-Delmotte (@valmasdel) April 14, 2016

In the IPCC’s words, the special report will cover “desertification, land degradation, sustainable land management, food security, and greenhouse gas fluxes in terrestrial ecosystems.”

While the five topics are interrelated, it may be a challenge to address all of them adequately in one report, says Dr Andy Challinor, professor of climate impacts and lead author on the food security chapter in AR5. He tells Carbon Brief:

Here, greenhouse gas “fluxes” refers to the cycling of carbon between land, plants and the atmosphere. If an element takes up more carbon than it emits, it is known as a “carbon sink” and it acts to slow the pace of warming. The reverse is called a “carbon source”.

It’s likely that food security will play a key part in the special report on 1.5C, Challinor adds:

§ Cities

The IPCC highlighted cities as another priority topic. But rather than being the focus of a whole special report, climate impacts on cities and their “unique adaptation and mitigation challenges and opportunities” looks set to be a common thread throughout AR6.

Highlighting cities in this way is “hugely important”, says Dr David Satterthwaite, senior researcher at the International Institute for Environment and Development (IIED) and co-ordinating lead author of the urban adaptation chapter in AR5. He tells Carbon Brief:

The IPCC will hold a special conference on cities to better get to grips with the issue, Lee told today’s press conference. He also indicated that cities will be a special report for the AR7 cycle and that the IPCC will be updating the methodology for how countries report their greenhouse gas inventories, to be published in 2019.

§ Better communications

How to better communicate its findings to the outside world is a “very important” element of the IPCC’s work, Lee told the press conference this morning.

From now on, the IPCC will involve communications specialists from the start in a bid to improve the readability of the reports, especially the “summary for policymakers”, he said.

This resolution stems from a two-day meeting in Oslo in February on how the IPCC could make its findings clearer and more engaging for policymakers, the public and the media.

Other interesting outcomes from the meeting included the recommendation to publish the early drafts of the assessment reports when they are in review. (Previously, they have been available only to “expert reviewers” but tend to have leaked to the press anyway.)

There was also the suggestion for a page limit on the Summary for Policymaker’s and a gentle reminder that they need only focus on policy-relevant bits, not be a comprehensive summary of each chapter.

The report from the meeting also recognised that “the media landscape is changing rapidly” and contained the intriguing recommendation that the IPCC should “be nimble and responsive so that it uses the best technology when future reports appear”.

Plans to hold a workshop on the “science of science communication” is an opportunity for the IPCC to see how lessons from the psychology and social science literature can help with the challenges it faces, says Dr Adam Corner, research director at Climate Outreach. He tells Carbon Brief:

More details on how the IPCC intends to approach communications in the future will come when it submits its “updated” communications strategy at the next big meeting in December.

In the meantime, it does at least look hopeful that the IPCC will have the cash for some such activities. The IPCC’s budget for 2016 allocates just under £200,000 in 2016 for the continued communication of AR5, and a proposal for the same amount in 2017, 2018 and 2019.

If and how the money is spent remains to be seen, however. Other documents available on the IPCC’s website suggest about £110,000 budgeted for AR5 communications in 2015 went unspent.