Sunday, September 29, 2013

My problems with the IPCC report

Below I will sketch two aspects of the IPCC's work which I find troubling. One relates to some interesting discussions on the thread The coming crisis of climate science which are worth pursuing in light of the two recent IPCC documents (Press release and Headlines document) reprinted here on Klimazwiebel. The other relates to the way the issue is presented by the IPCC.

Both the IPCC press release and the Headlines frame the climate issue exclusively as one of CO2 emissions. In so doing, other forcings are neglected and the message for policy makers is to perform a frontal attack on CO2 emissions (to create the ‘political will’ for such an enterprise, so to speak). This message has now been issued several times, with an inbuilt drama (the prospects get gloomier from assessment report to assessment report) but there is no effective policy outcome. There is no global agreement on the cards, and no national policies which radically cut CO2 emissions. CO2 emissions are rising and rising.

Assuming that the full text of all working groups in the new report will dedicate attention to non-CO2 drivers and other policy options, this will not get the same attention as the WG1 Summary for policy makers. This framing (or this construction) of the problem by the press release and 'headlines' will prime the political leaders and the mass media in a specific way. Is most unhelpful for practical political purposes.

While it is wise to (1) address the long term challenge of rising CO2, societies need to find ways to (2) cope with climate change (because we are committed to some change even if we stopped emitting today), and to (3) address non-CO2 climate forcings. The first strategy means technological innovation, the second adaptation, and the third exploiting co-benefits and applying pragmatic solutions for which regulations exist (mainly to do with air quality and protecting the natural environment). More about this can be found in the Hartwell Papers (here and here).

Now, on to the second problem. This is about presentation, or spin. As nature, and climate, do not speak to us 'through the IPCC', but are constructed by the IPCC in specific ways which select and emphasize specific aspects and neglect or attenuate others, we should pay careful attention to what is said, what is not said, and how it is said.

As Roger Pielke Jr. remarked, it is a good sign that the IPCC has abandoned the claim that tropical storms are getting more frequent and more violent (there is no such evidence, and Roger says 'Kudos to the IPCC for getting this right'). However, what is missing from the IPCC communications is an honest assessment of its previous statement, which it obviously thinks no longer tenable.

Generally, it would have been a good idea to compare the major messages from the 2007 report with those of the 2013 report and say where changes in assessment were made and why. The IPCC shuns such an exercise, and at its peril. The reason why it doesn't want to do this arguably (here I am offering a speculation) has to do with the desire to be perceived as sober, consistent, even infallible. Giving hints at a lack of confidence, the IPCC seems to assume, could provoke critical questions from the audience (and the heavy use of the word ‘confidence’ in the Summary for Policy Makers indicates that the IPCC wants to hammer home this exact point, that it has confidence…). But such a move gives rise to suspicion in the first place, as most of the interested audience can check for themselves what was said and how it was said last time, and if there are discrepancies between the two. So in reality this strategy is bound to backfire.

A very early example is the issue of climate sensitivity (which is now back at the centre of some commentators’ attention). As van der Sluijs et al have argued back in 1998, 'the consensus-estimate of 1.5°C to 4.5°C for climate sensitivity has remained unchanged for two decades. Nevertheless, during these years climate scientific knowledge and analysis have changed dramatically.'

One explanation offered by the authors is the following: ‘Advisory scientists also may have felt a need to create and maintain a robust scientific basis for policy action, which in our case means a consistent range of climate sensitivities. In may studies of science for policy, this has been seen as the prerequisite for maintaining support and credibility from all the actors and social worlds involved.’

In this case we have in fact seen a deviation from this range (upwards), only to now let it settle again in ‘safe terrain’. But the desire to present scientific statements in an authoritative manner while they are based on second guessing the audience of policy makers and the impact such statements make, is not helping the cause.


Pekka Pirilä said...

The AR5 SPM contains one table where comparisons with AR4 and SREX are presented. It's the Table SPM.1.

The text contains also other comparisons with AR4.

plazamoyua said...


When it is assumed that the CO2 content of the atmosphere is doubled and statistical thermal equilibrium is achieved, the more realistic of the modeling efforts predict a global surface warming of between 2°C and 3.5°C, with greater increases at high latitudes. This range reflects both uncertainties in physical understanding and inaccuracies arising from the need to reduce the mathematical problem to one that can be handled by even the fastest available lectronic computers.

2013, and a hell of a lot of money and computer power later:

Equilibrium climate sensitivity is likely in the range 1.5°C to 4.5°C

If this is a trend, with three more decades of science, and "some" more money and computing power, we will have something like 1.0ºC - 5ºC

Yes, I am joking. But something doesn't smell very good. Particularly, when you try to ask for the math behind the 95% - 100% probability figure.

But there is something bothering me more than such more or less funny details. Maybe someone here may tell me. Is about oceans. The idea that "the sea ate the warming".

Is it true that the measured heat going into the sea is in the ballpark of 0,5 W/m>2? I understand it may not be the best of measures, but that seems to be what they have. Is it over 90% of the heat into the system? The IPCC AR5, according to their figure SPM.5, has a total radiative forcing of around 2.3 W/m^2. How is it that 0,5 W/m^2 is a "huge" ammount, and not a "not enough" ammount? I must be missing something, but have no clue.

@ReinerGrundmann said...


thanks for your comment. I have seen the table (which is colour coded but needs guesswork, hopefully will be better in the final publication) but there is an important footnote at the bottom which contains caveats as regards the possibility of direct comparisons between AR4 and 5:

'The direct comparison of assessment findings between reports is difficult. For some climate variables, different aspects have been assessed, and the revised guidance note on uncertainties has been used for the SREX and AR5. The availability of new information, improved scientific understanding, continued analyses of data and models, and specific differences in methodologies applied in the assessed studies, all contribute to revised assessment findings.'

Would you say that the press releases are doing a good job at saying where the new report differs from the last?

Would you say the SPM does a good job at explaining where the new report differs from the last?

Leonard Weinstein said...

There still is no reasonable support to the claim: "(2) cope with climate change (because we are committed to some change even if we stopped emitting today)"
While increasing CO2 is likely largely due to human activity, the finite fossil fuel limitations and eventual increasing nuclear or other source of "clean" power (possibly LENR) would limit the increase. The only clear effect of increasing CO2 has been improved greening of the Earth. No temperature rise is clearly shown to be mainly due to human activity, although it is very likely a portion of the local variation is likely due to human activity. The stalling and projected dropping of temperature in the next several decades give lie to the "problem", with a small but general advantage to small levels of warming. Since we are likely approaching the end of the Holocene, and expect a cooling trend, the warming may in fact be the only thing that is saving us (cold is MUCH worse that warm). I suggest do nothing until the real facts are sorted out. Quit crying wolf, since one may come and we may be pushing in the wrong direction.

Pekka Pirilä said...

I don't think that the SPM is really good for anything. It's too brief for explaining anything clearly. Whatever is written there is often misunderstood and misused. It's more an indication of what the delegates can agree upon than a proper presentation of the scientific content of the full report.

The TS has been much better in giving an overview of the scientific content. We'll see soon, how true that is for AR5 WG1.

plazamoyua said...

- The direct comparison of assessment findings between reports is difficult. For some climate variables, different aspects have been assessed

2007 (by heart):

More than half of the warming is very likely caused by the increase of greenhouse gases.


It is extremely likely that human influence has been the dominant cause of the observed warming.

So, is it more likely in IPCC 2013 that greenhouse gases caused more than half of the warming? I couldn't tell. I would say less likely, but, who knows?

@ReinerGrundmann said...

Pekka -5

Yes, of course, but who reads the technical summaries? The 'Headline' document is supposed to be used for, well, headlines. And the SPM is for policy-makers, co-written by policy makers. Would it not be an alternative to have a scientific report (without government participation) which then is communicated in appropriate ways?

Hans von Storch said...

Reiner, we try just that with our BACC efforts. Governments consider our report on the Baltic Sea Region through HELCOM.

Pekka Pirilä said...

February 2011 I wrote a post The impossible task of IPCC. Writing a SPM that's balanced, understandable, and covers all requirements is surely even less possible. Getting government representatives agree on that doesn't make the task any easier.

plazamoyua said...

Pekka, the big problem I see is why should the government's representatives "negotiate" the advice the governments are going to receive. Sounds crazy.

Pekka Pirilä said...


Negotiating on the SPM may be seen also as a step in making governments more knowledgeable of the content of the report. Agreeing on SPM is also a (weak) commitment of the governments to the its conclusions.

The individual declarations that refer to SPM deviate often (usually?) so much from the compromise text that they are just on more layer on top of the full report, TS, and SPM. This extra layer has strong colors given by those who mix it.

plazamoyua said...

Hmmm, I am not sure, Pekka. One thing would be a list of clear questions by the governments, to be answered by the scientists. But this negotiation, line by line, word by word, by those who are supposed to be advised, I don't get the reasoning behind it.

lucia said...

I haven't confirmed numerical values. But it is the case that if quantified in Joules, accumulated heat in the ocean will overwhelm that in the atmosphere. It's not entirely clear how this should be interpreted. For example: if one increased the current through an incandescent lightbulb filament and monitored the amount of heat in joules accumulated in (a) the filament itself, (b) the gas inside the bulb and (c) glass casing holding the air,

the heat accumulated in the glass casing (particularly if the glass casing is thick and is not fully transparent), might be larger than accumulated by the gas inside the bulb or the filament. Nevertheless, the temperature of the filament would likely be more important if one is trying to estimate the lifespan of the filament.

As far as I can tell the main advantage to monitoring OHC is that the system has greater capacitance and averaging involves features of climate that span a large volume rather than a thin layer so we see less noise.

The disadvantage to comparing OHC to observations is that the IPCC hasn't been publishing OHC projections and the OHC observations come out slowly. Moreover we don't have a long history of good OHC measurements at depth. Given the current tendency to explain the haitus in terms of OHC warming it would have been nice for the IPCC to put together OHC projections. But I think the explanations may have come to late to motivate anyone to put together any such projections. In the meantime, people will certainly continue to compare observations to projections.

plazamoyua said...

Thanks a lot, Lucia.

I understand now I was wrong, and I am dealing with the "why". I'll get it eventually.

I see in An update on Earth's energy balance in light of the latest global observations (Graeme Stephens and a lot) some interesting data. They give the imbalance for the models. But quite different TOA budget and surface budget in the models. In the observations is impossible to say because the uncertainty is huge.

For the models, 0.9 at surface, and 2.2 at TOA, as mean imbalance in W/m^2.

Observed, 0,6 +/- 17 (no typo) at surface, and 0.6 +/- 0.4 at TOA.

Image here;

So, the discrepancy of something around 0.5 W/m^2 with the models is not as big as I thought. It is not "worse than we thought", though. On the contrary. And, apparently my error was comparing surface with TOA, or something so.

Thank you.

Anonymous said...

The "Klimazwiebel Litmus Test" in action!

On german TV (Nano) somebody asked if it is a good or a bad thing when the global heat disappears in the abyss... Guess what?

Some years ago some scientists told us that much of the heat had already disappeared and would come back, amplifying global warming (it is 5 past 12).

It is worse than we thougt and more confident than ever? Litmus test failed?!

I bought the new c't magazine and couldn't believe my eyes. IPCC over several pages and the models correpond 99,99% to reality. Only the dumb will doubt!

We have october the first not april.

Yeah, the skeptics have won.

Please tell me that this time it's a joke, where is the hidden camera?

By the way, what would happen if we would "radically cut CO2 emissions"? Where are the models?

Imho there is absolutely no will to discuss this matter in a down to earth and effective way.


Roger said...

Hi Reiner - Your comment on the need to properly assess non-CO2 human climate forcings is insightful. The 2013 WG1 IPCC report does not do this even close to adequately in the individual chapters.

For how I recommend such an assessment be completed, please see

National Research Council, 2005: Radiative forcing of climate change: Expanding the concept and addressing uncertainties. Committee on Radiative Forcing Effects on Climate Change, Climate Research Committee, Board on Atmospheric Sciences and Climate, Division on Earth and Life Studies, The National Academies Press, Washington, D.C., 208 pp

Roger said...

In the NRC 2005 report, for example, it was written that

"Several types of forcings—most notably aerosols, land-use and land-cover change, and modifications to biogeochemistry—impact the climate system in nonradiative ways, in particular by modifying the hydrological cycle and vegetation dynamics. Aerosols exert a forcing on the hydrological cycle by modifying cloud condensation nuclei, ice nuclei, precipitation efficiency, and the ratio between solar direct and diffuse radiation received. Other nonradiative forcings modify the biological components of the climate system by changing the fluxes of trace gases and heat between vegetation, soils, and the atmosphere and by modifying the amount and types of vegetation. No metrics for quantifying such nonradiative forcings have been accepted. Nonradiative forcings have eventual radiative impacts, so one option would be to quantify these radiative impacts. However, this approach may not convey appropriately the impacts of nonradiative forcings on societally relevant climate variables such as precipitation or ecosystem function."


Regional variations in radiative forcing may have important regional and global climatic implications that are not resolved by the concept of global mean radiative forcing. Tropospheric aerosols and landscape changes have particularly heterogeneous forcings. To date, there have been only limited studies of regional radiative forcing and response. Indeed, it is not clear how best to diagnose a regional forcing and response in the observational record; regional forcings can lead to global climate responses, while global forcings can be associated with regional climate responses. Regional diabatic heating can also cause atmospheric teleconnections that influence regional climate thousands of kilometers away from the point of forcing. Improving societally relevant projections of regional climate impacts will require a better understanding of the magnitudes of regional forcings and the associated climate responses.

The IPCC has failed yet again to address these climate issues.

@ReinerGrundmann said...

Thanks for your comments, Roger. Does this not mean that the IPCC violates its own mission of providing policy-relevant, yet policy-neutral advice?

Anonymous said...

Sorry for asking again:

By the way, what would happen if we would "radically cut CO2 emissions"? Where are the models?

(Imho there is absolutely no will to discuss this matter in a down to earth and effective way.)

I meant to ask what will happen to global economics?

What will happen to people who are unable to buy energy? How will they farm the land?

I've just watched Teleakademie on sunday. First picture (from the Bildzeitung):


Kommentar des Professors:

ENDLICH ist der Klimawandel in der Mitte der Gesellschaft angekommen .... blah blah blahh ... Atomkraft ist endgültig böse und out... blah blah blahh ....

Sorry I had to switch to another channel. If this is what our children learn, I'm very disappointed. After the years of "Aufklärung" these are the years of "Disinformation".

For god's sake, how can you seriously want to fight global warming with green energy and disregard atomic energy. Imo this is pure dishonesty.

Why do we talk on this blog about correlation by pure luck if it's dishonesty. Why talk about the character of physical laws or theories about what-I-don't-know if it's dishonesty. All this funky social science stuff cannot make us believe that there isn't something wrong with climate science, the IPCC or whoever.

Science has to deal with facts, not with luck. And the facts look bad actually.

Underdetermination is not the culprit. We doubters have to see this shit everyday on TV in magazines (c't Magazin) etc. etc. etc. Sorry