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All IPCC definitions taken from Climate Change 2007: The Physical Science Basis. Working Group I Contribution to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Annex I, Glossary, pp. 941-954. Cambridge University Press.

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Time to change how the IPCC reports?

Posted on 16 October 2013 by Kevin Trenberth

This is a re-post from The Conversation

This week, the Intergovernmental Panel on Climate Change (IPCC) released the outcomes from Working Group I (WG-I) of the Fifth Assessment Report on the physical climate change. The IPCC has issued four previous assessments, in 1990, 1995, 2001 and 2007. Should there be another one in 2019? Or should IPCC reports evolve along with its findings and the state of the climate?

A case can be made that the IPCC should declare success and do things differently in future. There are some aspects of the IPCC process that should be retained, but the burden on the climate community in endlessly producing unfunded reports is too much. More importantly, society’s needs have changed.

What does the IPCC do?

The role of the IPCC is to provide policy-relevant but not policy-prescriptive scientific advice to policy makers and the general public. Each new IPCC report reviews all the published literature over the previous five to seven years. It assesses the state of knowledge, while trying to reconcile disparate claims, resolve discrepancies and document uncertainties.

In 1995, the IPCC first raised headlines when it said “The balance of evidence suggests a discernible human influence on global climate”. Its findings were an important input to the Kyoto Protocol.

The third assessment reported “there is new and stronger evidence that most of the warming observed over the last 50 years is attributable to human activities”. The fourth report in 2007 stated that “warming of the climate system is unequivocal” and it is “very likely” due to human activities.

Later in 2007, the IPCC won the Nobel Peace Prize, jointly with Al Gore Jr, “for their efforts to build up and disseminate greater knowledge about man-made climate change, and to lay the foundations for the measures that are needed to counteract such change”.

Two major reviews are carried out in producing the report. The first is by experts and the second includes governments. Climate “sceptics” can and do participate, some as authors. All comments are responded to in writing and result in many changes in the report. The process is overseen by two or more review editors for each chapter.

United Nations rules require a unanimous consensus to be sought. Negotiations occur over wording to ensure accuracy, balance, clarity of message, and relevance to understanding and policy. The strength is that it is a consensus report but the process also makes it a conservative report. The rationale is that the scientists determine what can be said, but the governments determine how it can best be said.

However, the IPCC format has always created certain difficulties. Huge numbers of scientists are involved, but their contributions are voluntary. It has been difficult for information to flow between groups. The effort is huge, cumbersome and burdensome.

We need more up-to-date information

Given the findings, a key question is: what should be done about them?

It is not the role of IPCC to decide, but it is the role of IPCC to lay out the options and likely consequences. There is now an imperative to recognise that climate change is with us and we must plan for it in every way possible. The climate of the past is simply no longer a good guide to that in the future.

We need to develop climate services in the broadest sense to provide a continuous stream of information on how the climate is changing, why it is changing, what the expectations are on various time horizons, and how best to plan for the future climate. It is no longer pragmatic to wait for six years or so for another report.

Because of the importance and costs associated with climate variability and climate change, many of the topics need to be assessed continually. It no longer makes sense for the activities of Working Group 1 (which assesses the physical scientific aspects of the climate system and climate change) and those of Working Group 2 (which looks at impacts, adaptation and options for coping with climate change) to be separated.

I am tempted to say the reports should become routine and operationalized, except there is nothing routine about dealing with the variety of challenges facing us. Accordingly, there must be an ongoing strong research component on how to continually improve the tools and information, even as products are developed and disseminated through extensive outreach efforts.

Time for reports to evolve

There are already some aspects of IPCC reports that have become routine through the “State of the Climate” reports published mid-year by the Bulletin of the American Meteorological Society. The 2012 report came out in August 2013 and contained 238 pages. It lacks the rigour and review of the IPCC reports but has been an excellent step in the right direction. In addition, many nations have their own annual reports.

Other aspects must be picked up by climate services, perhaps through the World Meteorological Organization initiative “Global Framework on Climate Services”. The goal is to establish a comprehensive climate information system that includes observations and monitoring, product dissemination, research, modelling and applications, and user services.

The IPCC already issues special reports on “hot topics” as well as technical reports that often cut across different working groups. This is a way for the IPCC to continue to play a major role and not lose the procedures developed.

There is a continuing need to be responsive to governments but with targeted reports. Perhaps a model is the reports put out by the National Research Council in the United States? These are rigorous reviewed reports assembled by panels of experts, and customised to the task at hand, often at the request of Congress or the government agencies. They are deliberative but not locked to a particular timetable.

The service the IPCC offers in giving an overview of climate science has been invaluable. In the past, it has also been highly effective. But as climate change moves more rapidly, and as our response has to move more rapidly to keep up, the IPCC may have to find a new way to keep us informed.

Read more IPCC analysis here, and see debunkings of common IPCC-related myths here.

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Comments 1 to 10:

  1. With the greatest respect for Kevin Trenberth, I disagree.  The IPCC provides an impartial, conservative benchmark on the state of climate science.  As a consequence, its reports have a substantial impact in convincing the general society of the reality, and danger of climate change.  It is for that reason the denier movement expends so much energy in attacking the IPCC.  If the IPCC substantially changes its mission, that will be portrayed by deniers as a concession of defeat in its current mission, a portrayal that will resonate with the public.  Therefore such a move would be a backward step in attempts to get global policy settings that will adequately tackle climate change.

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  2. Tom@1,

    Some aspects of Kevin's suggestion are reasonable and should not be portaryed as "a concession of defeat in its (IPCC) current mission". BTW, deniers are and will be trying to downplay/denigrade inconvenient science no matter how presented.

    For example, here:

    It no longer makes sense for the activities of Working Group 1 (which assesses the physical scientific aspects of the climate system and climate change) and those of Working Group 2 (which looks at impacts, adaptation and options for coping with climate change) to be separated

    I tend to agree. There might be no point in analysing certain aspecte of climate science over and over because it's settle science. I think no one disputes that human CO2 emissons are causing warming (except lunatics), even policy makers-deniers like Tony Abbott acceptsa that, so WG1 report should be scaled down. However, the same Abbott denies that CTax/ETS is the effective market way to tackle the emission, so WG2/3 reports should be scaled up as they are needed now more than ever.

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  3. It seems incredible that we wil have to wait 6 years for the next IPCC Report, and this one is already out of date.

    Why not a shorter "State of the Global Climate" Report in 2 or 3 years? I agree that the emphasis should move to policy-based reports.

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  4. Since the IPCC sits in the net of UNEP, and since many of the UNEP reports deal with managing future change in general, perhaps it is time to consider incorporating a number of Earth and environment reports, including the IPCC one, into a more encompassing, multi-disciplinary five year report card on the state of the planet. Though I'll be honest the logistics would be mind-numbing. 

    This would allow the IPCC to continue a version of it's long-standing review of recent developments in climate change, in particular WG2, but in a context of how this fits in with all the other issues facing the planet and our stewardship of it. It might also divert some of the rabid politicisation of the suppoed 'debate' on climate, which has descended in many ways into a playground punch-up.

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  5. Fergus:

    As a matter of policy I think your idea is a very good one, in that incorporating IPCC reporting into wider UNEP policy documents is a useful (if time-consuming) process.

    I doubt, however, that it would do much to end unconstructive pseudo-debate or convince self-styled skeptics to lay down their rhetoric. The UN and its branch organizations are not, to my knowledge, well-received among the circles that self-styled climate skeptics appear to prefer.

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  6. Need a Ministry of Climate Information... one can see daily information that's important. 

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  7. You absolutely need to update AR5 figures 6.25 and 6.27. 

    6.25 -Compatible fossil fuel emissions simulated by the CMIP5 ESM models for the 4 RCP scenarios

    This figure needs to be updated to show a 2-sigma uncertainty.  A 68.2% uncertainty band is doing us all an incredible disservice.

    6.27 -Compatible fossil fuel emissions for the RCP4.5 scenario (with and without carbon cycle feedbacks)


    This figure needs to be updated to show 2-sigma uncertainty as well as RCP 8.5 scenarios.

    I understand why a 2-sigma uncertainty wasn't shown, because of the fat tails of carbon cycle feedbacks and equilibrium climate sensitivity uncertainties.

    The risk associated with the potential for a 2-sigma error are so great, it is vital that these uncdetainties are reflected in the AR5, even if the authority of the report may seem diminished.  This is a scientific exercise, not a political one.

    in other words.  would you propose that the designer of a nuclear power plant only use a 1-sigma uncertainty for the integrity of the reactor pressure vessel, so that her calculations appear to be very precise and authorative?  NO, of course you wouldn't.

    well, the RCP 8.5 ECS and climate cycle feedback uncertainties directly affect potential mitigation solutions.  If we don't take that into account then our hopes to adequately address them will fail.  With results that are many orders of magnitude worse than a total nuclear power plant meltdown.

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    Moderator Response:

    [JH] Is your request directed to the IPCC or SkS?  

  8. Is frequency of IPCC reports really the issue? How much have things really changed between AR4 and AR5? I've never had a sense that AR4 was very out of date or very far off the mark in the last few years. One of the things that I like about IPCC Assessment reports is that they're done properly. I've never read such an awesome synthesis of a complex subject anywhere else. I wouldn't mind seeing them done more often if they're going to be as good quality.

    More importantly, humanity ought to fund the IPCC properly, particularly if the IPCC is going to start producing more products, in more innovative ways (and, if needed, more often). I find it incredible that IPCC ARs, which are of such massive importance to the future well-being of our species (and many others) are written largely through voluntary efforts of already very busy scientists (although certain commentators will have us believe that climate science is just one big gravy train, I've never noticed science as being a particularly lucrative career, and I can imagine that the overall hourly rate is rather low, especially for those hundreds of experts who selflessly give up their time to work on IPCC assessment reports.)

    The IPCC could really help us prevent a whole of trouble in the future, so it ought to be much better funded.

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  9. Composer at #5; Yes, this is the elephant. The UN already hits the spectrum of politicised polemic in the USA (I don't think too many other countries have the same track record of disavowal). Such a process would simply draws cries of 'Lo the Antichrist rises' and similar nonsense. It would be changing one punchbag for another. But would it be a better means of providing a context for policy decisions?

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  10. The infrequent release of IPCC reports does not really bother me, with such a comprehensive and complex document it takes me a long time to read and understand it in any detail. 

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