'97% consensus' apparently doesn't exist at the IPCC

Consensus? What Consensus? You’d think they’d be able to agree on this most important number. They did for AR4.

nobest-estimate-sensitivity[1]

That footnote is on page 11 – h/t to Barry Woods. Directly above it is the statement on climate sensitivity

IPCC_ECS_AR5_SPM

Yet, they are 95% certain.

Read it here: Summary for Policymakers (PDF)

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September 27, 2013 12:10 pm

it would seem that their is an interesting debate within climate science between modellors at the high end of the IPCC range (4.5C) vs those other climate scientists at the lower end of the range (1.5C)

September 27, 2013 12:12 pm

thus – No Consensus on the Consensus any more?
previously their was a 3C consensus value given

Rick
September 27, 2013 12:13 pm

Orwellain

Latitude
September 27, 2013 12:14 pm

ok….so they did address the computer games fail

milodonharlani
September 27, 2013 12:14 pm

The high confidence consensus is that there is a lack of agreement on the values.

milodonharlani
September 27, 2013 12:22 pm

Summary of the Summary from AR6, finding ECS to lie in the range of 1to 2 degrees C:

Jimbo
September 27, 2013 12:31 pm

Hi Anthony,
Just a small point.
On the September 23, 2013 you posted Access: The “leaked” IPCC AR5 draft Summary for Policymakers
I noticed (here) the word “predictions” mentioned once.

The global mean surface temperature change for the period 2016–2035 will likely be in the range of 0.4°C to 1.0°C for the set of RCPs. This is based on an assessment of observationally-constrained projections and predictions initialized with observations (medium confidence).
http://wattsupwiththat.files.wordpress.com/2013/09/wg1ar5-spm_fd_final-1.pdf

The paragraph has changed on the AR5 report and the word has dissappeared. My comment was sarky, that the IPCC just couldn’t resist in making predictions (according to Trenberth they never have).

Jimbo
September 27, 2013 12:32 pm

Should be: disappeared

Geof Maskens
September 27, 2013 12:59 pm

As the projected admitted ‘dangerous’ warming approaches zero, the IPCC confidence level approaches 100%. I think I can guess where this is heading – but how long this will take, I have no idea.

Lil Fella from OZ
September 27, 2013 1:07 pm

Yes, the consensus does exist. It was another fabrication by desperate people to push their own barrow!

DC Cowboy
Editor
September 27, 2013 1:14 pm

I remember Mann in 2010 showing how they had ‘nailed’ the sensitivity at 3C.

DC Cowboy
Editor
September 27, 2013 1:16 pm

“assessment of observationally-constrained projections and predictions ”
What’s the difference between a ‘projection’ and a ‘prediction’?

September 27, 2013 1:23 pm

dccowboy:
At September 27, 2013 at 1:16 pm you ask

“assessment of observationally-constrained projections and predictions ”

What’s the difference between a ‘projection’ and a ‘prediction’?

The IPCC makes projections based on scenarios of future greenhouse gas emissions. And the IPCC defines its projection with highest confidence to be its prediction.
Richard

Svend Ferdinandsen
September 27, 2013 1:36 pm

They could get 99% concensus if the range is between 0 to 6K. So why all the fuzz.
I only wonder how they could be more confident in the models when they make the range wider.
Or is it like a weather forecast that forecasts any kind og weather to be sure.

September 27, 2013 1:48 pm

Barry Woods says at September 27, 2013 at 12:10 pm

it would seem that their is an interesting debate within climate science between modellors at the high end of the IPCC range (4.5C) vs those other climate scientists at the lower end of the range (1.5C)

1.5C from the baseline of 1851-1900. Not from now.
That means the lowest range that is scientifically mainstream is 0.8C this century compared with 0.7C last century… in other words no discernible impact from CO2 emissions at all.
Extreme scepticism is now mainstream science.
So the lukewarm scepticism that seems so prevalent round here must be the next establishment.

September 27, 2013 2:03 pm

i know, from the baseline, so just possibly another 0.6C for a doubling of CO2, plus feedbacks, isn’t too scary!

Louis
September 27, 2013 3:00 pm

Lack of global warming is causing the once solid IPCC consensus to thaw very rapidly. If this keeps up, the sea of unemployment may soon overflow its shores with the addition of climate scientists.

Brian H
September 27, 2013 3:00 pm

My comment was sarky, that the IPCC just couldn’t resist in making predictions (according to Trenberth they never have).
Jimbo says:
September 27, 2013 at 12:32 pm
Should be: disappeared

and: snarky

Hot under the collar
September 27, 2013 3:13 pm

Do you think that was the smallest font size they could find for the footnote?

Jimbo
September 27, 2013 3:14 pm

No best estimate for equilibrium climate sensitivity can now be given because of a lack of agreement on values across assessed lines of evidence and studies.

After many years, the best super computers on the planet, the finest brains evaaaaaaah, a Nobel Prize, a flood of recent papers reducing climate sensitivity, and they can’t agree on a “best estimate…”. But they mention “best estimate” / “best estimates” SEVEN times for other climate indicators and fail on one of the most important “best estimates.”
Tomorrow’s average temperature in London is forecast to be between -5C and 48C with a best estimate between those temperatures we just gave you. The best estimate for the global mean temperature in 2100 is between 13C and 20C. I can’t fail my friends in my projections and scenarios. What a bloody joke.

jonny old boy
September 27, 2013 3:30 pm

Deniers !!! thats what the IPCC are…. they deny the meaning of the word “certain”…. you can not be 95% “certain” of something…. they are not “certain” skeptics , they are deniers.

Jimbo
September 27, 2013 3:40 pm

Are these people worried? They don’t sound it in public but in private they are terrified. And this was between 2005 and end of 2009! Four years later their confidence has INCREASED to 95% in the face of continued temperature standstill! This is how you know we are dealing with a con job.

Dr. Phil Jones – CRU emails – 5th July, 2005
The scientific community would come down on me in no uncertain terms if I said the world had cooled from 1998. OK it has but it is only 7 years of data and it isn’t statistically significant….”
—————————
Dr. Phil Jones – CRU emails – 7th May, 2009
‘Bottom line: the ‘no upward trend’ has to continue for a total of 15 years before we get worried.’
—————————
Dr. Kevin Trenberth – CRU emails – 12 Oct. 2009
“Well I have my own article on where the heck is global warming?…The fact is that we can’t account for the lack of warming at the moment, and it is a travesty that we can’t. The CERES data published in the August BAMS 09 supplement on 2008 shows there should be even more warming: but the data are surely wrong. Our observing system is inadequate.”

September 27, 2013 3:42 pm

While Roseanne Roseannadanna may have had the last word…I think Donald’s explanation is the best analogy to the state of climate science – https://www.youtube.com/watch?feature=player_detailpage&v=wr5C3nasFKA

Jimbo
September 27, 2013 3:43 pm

And they can’t give us a most likely figure on climate sensitivity. They can’t because there are two opposing forces. The scientific and the political.

Jquip
September 27, 2013 3:58 pm

dccowboy: What’s the difference between a ‘projection’ and a ‘prediction’?
Depends on the field of discussion. A projection can be a coordinate transformtation, as in geometry. eg. Projecting a solid onto a plane. A projection is also the case when you accuse of others *not* of what they are guilty of, but you are; common in partisan discussions. eg. An ideologue accusing an empiricist of being a ‘Science-denier’ It can also be a prediction of the future. eg. We predict that in 30 years Manhattan will be under water.

September 27, 2013 4:00 pm

The sensitivity issue and the failure of the IPCC to even try for a number means that the entire AR5 is a waste of paper.
A policy maker needs to be able to at least pretend that a “carbon tax” or “cap and trade” will have some impact – however minimal – on warming. Sensitivity is the lynch pin which connects the reduction of CO2 emissions to the reduction of temperature: but if the IPCC can’t come up with a number we sceptics can and will point this out and the reduction claim will collapse.
If I was a politician in charge of the climate file I would be livid.

Auto
September 27, 2013 4:01 pm

What’s to say?
Charlatans exit stage Left [Left – of course].
And hope the Police don’t have to battle through snow-storms to arrest you for an offence against humanity . . . . . .
The science was settled.
Ahhhhhhhhhhhhhhhhhhh Hahhhhhhhh!
Now it’s not.
And yet we still have the bird-choppers, the humungous taxes on non-renewable fuels,and DAFTIE POLITICOS seeking more of the same, whilst – as Willis has so starkly reminded us – increased energy prices are killing people

September 27, 2013 4:21 pm

IPCC did not agree on a value for climate sesitivity!

Ted Carmichael
September 27, 2013 4:37 pm

Ah, now I understand. They had to lower the bottom end of the range, due to new publications and the flat temperature trend. They had to keep the high end of the range for political reasons and/or stubborn stalwarts. And since the *range* is now larger than the AR4, they probably felt forced to also increase their confidence … otherwise, they’d be going backwards. (Or rather, they would have to *admit* that they are going backwards.)
As Steve McIntyre said, it would be better if they just addressed these issues head on – cover the science and ignore the politics. But they are seemingly incapable of that. This won’t end well for the IPCC.

Jimbo
September 27, 2013 4:45 pm
Steve from Rockwood
September 27, 2013 4:58 pm

Barry Woods says:
September 27, 2013 at 12:10 pm
———————————–
it would seem that [there] is an interesting debate within climate science between modellors at the high end of the IPCC range (4.5C) vs those other climate scientists at the lower end of the range (1.5C)
===============================
I’m always confused at the low end, high end prediction. Is it the boundary of their errors assuming the same inputs but different model runs? Or is the low end if we stop burning fossil fuels and the high if we continue business as usual? Also 1.5 and 4.5 don’t mean much without a constraint such as over the next century starting in 2015, or from present to 2099 etc. Always enjoy your comments Barry.

Theo Goodwin
September 27, 2013 5:31 pm

This is an opportunity for skeptics. We must insist that any claim of consensus has to be about well formulated scientific statements rather than about vague statements such as “Earth is warming.” In this case, the IPCC has published the fact that there is no consensus about climate sensitivity.

u.k.(us)
September 27, 2013 6:26 pm

I still remember when R. Gates had the sensitivity thing all figured out.

Pippen Kool
September 27, 2013 7:12 pm

The disappointing thing for many of you is that climate scientists have moved past your 97% consenus hang up and are arguing about exactly how much humans are forcing warming, not if they are forcing warming. You just need to catch up a little, you are 5 years behind, if not 15.

CRS, DrPH
September 27, 2013 7:22 pm

…I just had a thought…as Anthony has shown, temperature readings are likely over-estimated due to urban heat island (UHI) effects, and poorly sited weather stations (near airport runways, air conditioning vents, cinderblock building etc.)
http://surfacestations.org/
…so, isn’t it likely that the pause in warming is actually a decline? To paraphrase Dr. Trenberth…our observing system is inadequate (to measure the decline).

Theo Goodwin
September 27, 2013 8:04 pm

PippenY Kool says:
September 27, 2013 at 7:12 pm
You must be new here. We have been discussing how much humans are contributing to warming for many years. What the scientists have not done is engage in empirical research into the matter of “forcings and feedbacks.” We have been discussing those questions for years. Willis Eschenbach has offered testable hypotheses. Bob Tisdale has become the world’s expert on the data associated with ENSO. The empirical work necessary to make sense of Trenberth’s “heat hidden in the deep oceans” is discussed often. I am fairly confident that mainstream climate scientists will never take up these matters because there is not one shred of empirical evidence that supports their claim that manmade warming will be harmful. Once again, they have nothing substantive to say about it in their report. When climate scientists move on it is because they need to change the topic.

Theo Goodwin
September 27, 2013 8:06 pm

CRS, DrPH says:
September 27, 2013 at 7:22 pm
Sounds good to me. Also, do not forget the fat fingers of Hansen and his minions “on the scale.”

Theo Goodwin
September 27, 2013 8:10 pm

Theo Goodwin says:
September 27, 2013 at 5:31 pm
Also, we must insist with the IAC and Judith Curry that the IPCC implement the IAC’s guidance that all statements of attribution must be traceable to the people, both pro and con, who created them.

September 27, 2013 8:15 pm

He’s said it before, and he ain’t quitting til everyone hears “It’s the feedbacks, stoopid”!

Goldie
September 27, 2013 8:28 pm

So the consensus is that we think that the current hiatus is caused 50:50 by reduction in forcings due to volcanism and the end of the last solar cycle, and internal decadal variability. BUT we have only low confidence that we can actually quantify the reductions in forcing and medium confidence that we can quantify the internal decidable variability. Hmmmm that sounds like a total thumb suck to me!

thingadonta
September 27, 2013 8:44 pm

The temperatures and climate are going in the opposite direction to the certainty and reports of the IPCC.
So using their own logic, when they state that the temperatures are going in the opposite direction to solar output, and then conclude that solar output can’t therefore be driving them, I conclude that temperatures and climate therefore can’t be driving the IPCC’s reports and certainty.
Must be something else, some kind of strongly positive bureaucratic feedback that they have failed to account for in their claim of certainty.

DavidA
September 27, 2013 10:23 pm

They don’t know what a best guess is. They can’t state with high certainty what the figure should be, but FFS, they can still make a best guess!

David Harrison
September 27, 2013 10:53 pm

It brings to mind the lines from the Hilaire Belloc poem “The Microbe”:
“Oh! Let us never, never doubt
What nobody is sure about!”

September 28, 2013 12:10 am

Sensitivity and response to forcing.
Summary to Policy Makers, page 11 “The net feedback from the combined effect of changes in water vapour, and differences between atmospheric and surface warming is extremely likely positive and therefore amplifies changes in climate. The net radiative feedback due to all cloudt ypes combined is likely positive. Uncertainty in the sign and magnitude of the cloud feedback isd
ue primarily to continuing uncertainty in the impact of warming on low clouds. {7.2}”

Clouds have a very strong influence on the whole. If their impact is not known the first sentence does not make any sense. Which means: we don’t actually know if it is positive or negative and by how much. Cloud coverage measurement are not very accurate and precise; how can models be better?
Summary to Policy Makers, page 12: “The transient climate response quantifies the response of the climate system to an increasing radiative forcing on a decadal to century timescale. It is defined as the change in global mean surface temperature at the time when the atmospheric CO2 concentration has doubled in a scenario of concentration increasing at 1% per year. The transient climate response is likely in the range of 1.0°C to 2.5°C (high confidence) and extremely unlikely greater than 3°C. {Box 12.2}.”
and page 20: “Limiting the warming caused by anthropogenic CO2 emissions alone with a probability of >33%, >50%, and >66% to less than 2°C since the period 1861–188022, will require cumulative CO2 emissions from all anthropogenic sources to stay between 0 and about 1560 GtC, 0 andabout 1210 GtC, and 0 and about 1000 GtC since that period respectively23. These upper amounts are reduced to about 880 GtC, 840 GtC, and 800 GtC respectively, when accounting for non-CO2 forcings as in RCP2.6. An amount of 531 [446 to 616] GtC, was already emitted by 2011. {12.5}
When all proved reserves of coal, oil and gaz (1715 Gigaton of Carbon) will have been burned then the CO2 concentration will reach approx. 925 ppm (my approximate calculation). There is a limit to CO2 induced warming. Nothing about this upper limit is provided in the summary.

Michele, Jürgen
September 28, 2013 12:59 am

Without additional comments … The „Last Climate Report of the IPCC” published in the “Wilhelmshavener Zeitung” (daily newspaper) on Saturday, Sept. 28, 2013 The last Climate report! [X]
Prof. Dr.-Ing. Juergen Michele Jade Hochschule Wilhelmshaven Friedrich-Paffrath-Straße 101 26389 Wilhelmshaven
Tel.: 04461 83043 E-Mail: juergen.michele@jade-hs.de Homepage: http://staff.fh-oow.de/michele/
Privat: Soestestr. 3 26419 Schortens ________________________________

rogerknights
September 28, 2013 1:05 am

Theo Goodwin says:
September 27, 2013 at 8:06 pm
CRS, DrPH says:
September 27, 2013 at 7:22 pm
Sounds good to me. Also, do not forget the fat fingers of Hansen and his minions “on the scale.”

Invisible THUMB!

See - owe to Rich
September 28, 2013 2:29 am

Steve from Rockwood says: I’m always confused at the low end, high end prediction. Is it the boundary of their errors assuming the same inputs but different model runs? Or is the low end if we stop burning fossil fuels and the high if we continue business as usual?

Steve, the low end and high end refer to the equilibrium climate sensitivity to a doubling of CO2. By this measure, it doesn’t matter how long it takes to reach that doubling. A low emissions scenario might mean we only get half a doubling, ever, whereas business-as-usual looks set to take us to 800ppm in about 200 years – assuming that all the present rate of increase is down to us, about which I believe there is some scepticism. Doubling from a pre-industrial of 280ppm to 560ppm would take us 80 years at current rates.
Rich.

DaveS
September 28, 2013 2:39 am

The prize for the most imaginative use of the phrase ‘improved understanding’ goes to… the IPCC.

Jimbo
September 28, 2013 4:08 am

Will Skeptical Science update their page in light of the ‘consensus’ on climate sensitivity being between 1.5c and 4.5c? I mean Cook et. al. did manufacture the ‘consensus’ after all.

A study led by Stefan Rahmstorf concluded “many vastly improved models have been developed by a number of climate research centers around the world. Current state-of-the-art climate models span a range of 2.6–4.1°C, most clustering around 3°C” (Rahmstorf 2008). Several studies have put the lower bound of climate sensitivity at about 1.5°C,on the other hand, several others have found that a sensitivity higher than 4.5°C can’t be ruled out.
A 2008 study led by James Hansen found that climate sensitivity to “fast feedback processes” is 3°C, but when accounting for longer-term feedbacks (such as ice sheet disintegration, vegetation migration, and greenhouse gas release from soils, tundra or ocean), if atmospheric CO2 remains at the doubled level, the sensitivity increases to 6°C based on paleoclimatic (historical climate) data…….
As you can see, the various methodologies are generally consistent with the range of 2-4.5°C, with few methods leaving the possibility of lower values, but several unable to rule out higher values………
http://www.skepticalscience.com/climate-sensitivity-advanced.htm

Vic Mather
September 28, 2013 4:49 am

I love your site and how you challenge
The climate change “consensus” crowd
I was diagnosed with cancer and have also now become disillusioned with
Conventional chemotherapy..here too
We have oncologists all subscribing to
Traditional dogma that chemotherapy
Is the preferred treatment for cancer
But I am a skeptic..I did an Internet search and found that chelation therapy
With vitamins could actually cure cancer: that’s something that modern so called medicine doesn’t want you to know
“Peer reviewed scientific literature” is really nothing but a conspiracy to protect those in power…keep up the good posts!

Andy
September 28, 2013 5:26 am

Presumably we can expect renewed attempts by the IPCC to try and get full UN syle immunity from prosecution for themselves as their edifice continues to crumble in the face of nature not doing what they project/predict. Reality certainly sucks for them ; )

Steve from Rockwood
September 28, 2013 5:57 am

. Thanks. I guess I owe you.

Richard M
September 28, 2013 10:57 am

CRS, DrPH says:
September 27, 2013 at 7:22 pm
…I just had a thought…as Anthony has shown, temperature readings are likely over-estimated due to urban heat island (UHI) effects, and poorly sited weather stations (near airport runways, air conditioning vents, cinderblock building etc.)
http://surfacestations.org/
…so, isn’t it likely that the pause in warming is actually a decline? To paraphrase Dr. Trenberth…our observing system is inadequate (to measure the decline).

I think the divergence between land based data sets like GISS and satellites is due to the continuing problem of UHI, etc. that is one reason that satellite data is the only reasonable data. Naturally, the IPCC used only the surface data because, without this contamination, there would be no warming at all..

starzmom
September 28, 2013 6:24 pm

The lack of consensus on equilibrium climate sensitivity reflects an improved understanding??? Is that the same as saying “we agree we don’t have a clue what is happening”?

Andy Wilkins
September 29, 2013 9:31 am

Dear Pippen Kool,
If everyone here at WUWT was 15 years behind the times (as you claim), then none of us would be aware of the 15 years long hiatus in warming.
However, ALL of us are aware of the flat-lined temps, so I’d say we’re all bang up to date knowledge-wise.
Are you aware of the rather inconvenient (for alarmists) lack of warming? Because if you’re not, then you really are 15 years behind the times.

more soylent green!
September 29, 2013 10:51 am

I have extremely high confidence they don’t know what they’re talking about.

Taphonomic
September 29, 2013 1:07 pm

Last night I saw upon the stair
Some global warming that wasn’t there
It wasn’t there again today
Oh, how I wish it’d go away