Sep 17, 2008
The IPCC report: what the lead authors really think
In the final months of the Intergovernmental Panel on Climate Change’s Fourth Assessment reporting in 2007, the world’s three leading climate science agencies asked people directly and intimately involved with the report for their views on how the process had gone and some of the key issues it raised.
The three agencies in question: the Global Climate Observing System Programme (GCOS), the World Climate Research Programme (WCRP), and the International Geosphere-Biosphere Programme (IGBP) are the world co-ordinators of observations and research on climate change. They also held a workshop in Sydney in October 2007 on Learning from the IPCC Fourth Assessment Report, for which I drafted an outline of a workshop paper, based entirely on responses to the survey.
Here I want to go back and check whether the first glimpse we received of the "real gut feeling" of some of the IPCC authors and co-ordinators as they finished up the humungous task of completing the Fourth Assessment Report held steadfast throughout the Sydney meeting process and the subsequent re-writings of views and clarification – and sometimes perhaps cleaning up – of opinions. I have done this because I believe it is essential for the climate change research community to be transparent and honest about what it can and cannot deliver and how, if ever, current inadequacies can be resolved.
What follows is the text I drafted one year ago which itself came entirely from quotes from IPCC lead authors responding to a questionnaire sent out by GCOS-WCRP-IGBP. The full details of the questionnaire and the replies submitted, some of which came in after this draft was written, have since been restricted but an early summary can still be found. (See related links).
In this article I report what these eminent folks said – every bullet point comprises a reply submitted by an IPCC respondent in mid-2007 and the only editing has been to improve the English, clarify or spell out acronyms.
Urgent policy issues that climate change research must tackle
• Monitoring the trajectory of climate change to assess whether we are heading into a danger-zone and how fast/where.
• Examining policy-driven questions to learn to understand how others see the world and what scientists need to do to help resolve such non-science priorities.
• Rolling reassessment building on what works, discarding what is weaker and revisiting with governments and stakeholders their priority needs.
• Establishing metrics of transient change impacts to detect and monitor the most likely (best predicted) changes of importance for rapid adaptation response.
• Assisting in determining what adaptation measures are needed beyond current coping capacity.
• Providing pathway options to obtain thresholds like the 2°C limit goal of the European Union.
• Fuller understanding of the carbon cycle and stabilizing emissions levels of greenhouse gases.
• Increasing confidence in the relationship between stabilizing emissions and temperature rise.
Serious inadequacies in climate change prediction that are of real concern
• The rush to emphasize regional climate does not have a scientifically sound basis.
• Prioritize the models so that weaker ones do not confuse/dilute the signals.
• Until and unless major oscillations in the Earth System (El Nino-Southern Oscillation (ENSO), Pacific Decadal Oscillation (PDO), North Atlantic Oscillation (NAO) and Atlantic Multidecadal Oscillation (AMO) etc.) can be predicted to the extent that they are predictable, regional climate is not a well defined problem. It may never be. If that is the case then we should say so. It is not just the forecast but the confidence and uncertainty that are just as much a key.
• Climate models need to be exercised for weather prediction; there are necessary but not sufficient things that can best be tested in this framework, which is just beginning to be exploited.
• Energy budget is really worrisome; we should have had 20 years of ERBE [Earth Radiation Budget Experiment] type data by now- this would have told us about cloud feedback and climate sensitivity. I'm worried that we'll never have a reliable long-term measurement. This combined with accurate ocean heat uptake data would really help constrain the big-picture climate change outcome, and then we can work on the details.
• [Analyse] the response of models to a single transient 20th century forcing construction. The factors leading to the spread in the responses of models over the 20th century can then be better ascertained, with forcing separated out thus from the mix of the uncertainty factors. The Fourth Assessment Report missed doing this owing essentially to the timelines that were arranged.
• Adding complexity to models, when some basic elements are not working right (e.g. the hydrological cycle) is not sound science. A hierarchy of models can help in this regard.
Climate change research topics identified for immediate action
• Thorough understanding of the physics and dynamics of the Greenland and Antarctic ice sheets, with a view to predicting sea level rise within 20% for a specified change in climate over the ice sheets.
• Simulation of the main modes of variability in each of the main oceans (e.g. ENSO and PDO in the Pacific, thermohaline circulation (THC), meridional overturning circulation (MOC) and AMO in the Atlantic, and monsoons in the Indian Ocean) is essential. Replicating relative changes over the past 50 years is essential and is an initial value problem for the oceans.
• Re-evaluation of the projections for sea-level rise, aiming for a consensus rather than a lot of publications criticizing the Fourth Assessment Report.
• Establishing the likelihood of Amazon die-back – carbon dioxide source instead of sink.
• Links between land use/cover change and greenhouse gas emissions.
• Bringing the carbon cycle models to a level comparable with the physical climate change models and fully incorporating them.
• Reducing climate sensitivity.
• Tackling the resolution problem properly (not easy!).
International organization issues, especially regarding the IPCC
• The IPCC was designed 20 years ago when the problem was less well-understood and political acceptance more fragile. We now need to focus more on solutions. Future IPCC reports must be more focused, shorter and timely. We absolutely need a complete re-think.
• The Fourth Assessment Report is rather weak at including the latest research and thereby is losing credibility in the science community. During the whole process it loses actuality [timeliness].
• Construct the Fifth Assessment Report on the Synthesis model, rather than the three separate disciplines in the Working Group model – it has had its run in my view – incredibly valuable but becoming a bit repetitive and may have little original to say other than "we told you so last time and mean it even more now!". This way people with very different understandings of science and policy problems and with very different world views would have time to work together to fashion real progress on interdisciplinary, policy-oriented questions from governments. The current Synthesis Report (SYR) is already very late in the game for such integrative understanding and thus is a difficult venue to accomplish interdisciplinary integration in the allotted time.
• Working Groups (WG) I and II ought to be rethought and perhaps combined with a different approach. WG III is involved in mitigation and is somewhat more separable except where effects of mitigation are sought and climate models have to be run to assess effects of "what if" scenarios.
• WGII is easily the weakest of the three reports. The reasons seem to be two-fold: (i) poor downscaling and (ii) the lack of a coherent methodology for impact study.
• Maintain ongoing interactions across the communities that populate the disciplinary working groups – like the core writing team of the Synthesis report at the moment – post-IPCC with a bit less stress to make a report and more time to learn from each other how to do integrative research to answer key questions like those posed above.
• Special reports on ice sheets and on the climate carbon-cycle feedback should be planned in 2-3 years, if not by IPCC then by someone else.
• Progress requires more attention to addressing basic model flaws. Without alleviating these, future IPCC assessments will look very similar each time. What a waste of resources...climate science will get what it deserves if it does not apply itself more to basics rather than what it is doing currently.
• Should have started the Synthesis Report team at least a year earlier while there was time for it to influence some of the Working Group reports.
Institutional/ infrastructure issues hamper climate change information delivery
• Problems identified, now we need to direct our science towards the "solutions".
• There is a strong need to promote merging of IGBP and WCRP and revitalizing the international framework for climate science.
• There are too many committees and working groups and way too much time spent on liaising between 'partners'.
• "Human-ware" is very much a depleted commodity, especially younger scientists having the urge and motivation to delve into climate problems. This rarely gets mentioned as a serious point.
• Simplify the international committee structure, reducing unnecessary overlap and complexity.
• Make the science of modelling more attractive to good young scientists. In part this requires less "publish or perish" management as model development is inevitably not a paper generator.
• More meetings to examine policy-driven questions with broader representations of disciplines, stakeholders and governments – not just to write and approve reports.
• Better interaction between modelling and climatological communities.
• Essential to involve the social and economic sciences more – need reliable cost estimates, need to develop adaptation options etc.
• Strategies for mainstreaming climate change adaptation to (sustainable) development.
• Attention to the simulation of "weather" by climate models, thus accounting simultaneously for the verification of the so-called "fast" and "slow" time-scale processes.
• More generally, much more is needed in coming to grips with real prediction as an initial value problem.
It seems to me, even one year later, that the urgency and forthrightness of many of these comments still hold and need to be shared, discussed and acted upon. Those that concern me most include the simple, but dastardly, statement that "until and unless major oscillations in the Earth System can be predicted to the extent that they are predictable, regional climate is not a well defined problem. It may never be. The rush to emphasize regional climate does not have a scientifically sound basis." This is underscored in another quote: "adding complexity to models, when some basic elements are not working right (e.g. the hydrological cycle) is not sound science." (The italics are mine.)
There are other, more organizational but still very pertinent views such as: "future IPCC reports must be more focused, shorter and timely"; "human-ware is very much a depleted commodity"; and "the Fourth Assessment Report is rather weak at including the latest research and thereby is losing credibility in the science community." Finally there is a cry from the heart – remember these quotes all come from IPCC lead authors, the guys at the coal face if we still dare cut coal – which says, "there are too many committees and working groups and way too much time spent talking!"
Did the final workshop outputs genuinely deliver these messages as clearly as they are stated here? Did we say "the IPCC was designed 20 years ago ... we absolutely need a complete re-think" and "we need more time to learn from each other how to do integrative research to answer key questions"? My personal view is that we did not. Perhaps due to the natural desire to tone down criticism in written documents and perhaps because some of us wonder what else can be said – e.g. WGI is "becoming a bit repetitive and may have little original to say other than 'we told you so last time and mean it even more now!'" Also there is real reluctance to state too baldly the magnitude of the challenges to be overcome before climate change research can deliver relevant results.
In some places there is an (unhealthy?) fear of mis- (or out of context) quoting by global warming "deniers". We are hesitant to stress comments such as "the Fourth Assessment Report missed doing this owing essentially to the timelines that were arranged." Another interesting example of this fear is that the original suggestion was to entitle the Sydney workshop, "What did the IPCC get wrong?" This proposal was quickly squashed in the corridors of the World Meteorological Organisation lest the anti-greenhouse lobby picked it up and repeated it as criticism of the IPCC.
Climate change research entered a new and different regime with the publication of the IPCC Fourth Assessment Report. There is no longer any question about "whether" human activities are changing the climate; instead research must tackle the urgent questions of: "how fast?"; "with what impacts?'; and "what responses are needed?" Climate change researchers cannot hide behind the need to improve models and observations any longer. Answers are now being demanded faster than, and at higher resolutions than, research can deliver.
It is clear that climate change will remain a risk management problem for the foreseeable future. However, the more we can constrain distribution functions of important process variables or outcomes like climate sensitivity or damages, the better will be humanity’s chances of adaptation. The cleverer we are in the design of relevant and deliverable climate change results, the sooner we constrain the potential for some really "dangerous" outcomes that cannot currently be ruled out at less than a 10% chance. One essential ingredient is transparency in communication. I hope that this article goes some way to ensure this.
• For those interested in finding out more, there are reports on the workshop in the reference list below (WMO, 2008 and Bojinski, S and Doherty S, 2008). And right now the final touches are being made to the full report of the responses – we hope it will be published next year (Doherty et al., 2009).
Bojinski, S., and Doherty S., 2008, Developing Strategies for Future Climate Change Science, Eos Trans. AGU, 89(11), 109
Doherty, S. J, Bojinski, S., Henderson-Sellers, A., Noone K., Goodrich, D., Bindoff, N. L., Church, J., Hibbard, K.A., Karl, T. R., Kajfez-Bogataj, L., Lynch, A.H., Mason, P.J., Parker, D.E., Prentice, C., Ramaswamy, V., Saunders, R.W., Simmons, A.J., Stafford Smith, M., Steffen, K., Stocker, T. F., Thorne, P. W., Trenberth, K., Verstraete, M.M., Zwiers, F.W., 2009, Lessons learned from IPCC: developments needed to understand and predict climate change for adaptation, 2008. Bulletin of American Meteorological Society, in press.
"IPCC Fourth Assessment Report", 2007, The contents of the reports of Working Groups 1, 2 and 3 and the Synthesis report are accessible from http://www.ipcc.ch/
WMO, 2008, Future Climate Change Research and Observations: GCOS, WCRP and IGBP Learning from the IPCC Fourth Assessment Report, Workshop and Survey Report, GCOS-117, WCRP-127, IGBP Report No. 58, World Meteorological Organization, (WMO/TD No. 1418), January 2008, Geneva, 68pp, see here.
About the author
Ann Henderson-Sellers holds an Australian Research Council Professorial Fellowship in the Climate Risk CORE of Macquarie University. Until 2007 she was the Director of the World Climate Research Programme based in Geneva at the headquarters of the World Meteorological Organisation.