Bishop Hill A sneak peek at the IPCC report
Aug 17, 2013 Climate: IPCC Reuters seems to have managed to get itself a peek at the IPCC report. Hard though it is to believe, things are worse than we thought.
Drafts seen by Reuters of the study by the U.N. panel of experts, due to be published next month, say it is at least 95 percent likely that human activities - chiefly the burning of fossil fuels - are the main cause of warming since the 1950s. That is up from at least 90 percent in the last report in 2007, 66 percent in 2001, and just over 50 in 1995, steadily squeezing out the arguments by a small minority of scientists that natural variations in the climate might be to blame. That shifts the debate onto the extent of temperature rises and the likely impacts, from manageable to catastrophic. Governments have agreed to work out an international deal by the end of 2015 to rein in rising emissions.
Reader Comments (76)
- I forgot to say the Dec 2012 Alister Doyle contains the phrase "The draft was shown on a climate change skeptic blog" ..surely he means on WUWT or on Donna's blogs when the AR5 memory sticks were leaked.
- Maybe we should have a new thread about AR5 pre-releases Sensitive information
- here's a Jul 20th 2013 piece from the Economist " A peek inside the next IPCC assessment"
It's not up to skeptics to come up with a debunk for pre-released reports. There is no need to judge stuff until it is fully published and all the facts are on the table, but we can stamp it with a
The activists standard technique is to plant a meme in the minds of journalists not educated in science.
- Red light warnings - Info is released straight the media instead of going through criticism in the standard peer review process *
- The report willl be big on "Scientists say" rather than actual "Science says", cos such journalists easily mix up Opinions with Validated Scientific Evidence.
(One you can take to the pub, the second you can take to the bank) ^^1
- The report will be big on emotion and pleadings for urgency, but low on real numbers.
- Within a month the activists will have moved on to the next scare story blowing a sigh of relief that they got away with another fib.
* That is a problem cos they'll be 1000 hyping headlines before the skeptics have done the full analysis & are trying to get the media to listen to them. The activists know the lie is done, as the media don't like to stop and go back and correct their stories.
^^1 I note in the 95% story they use the phrase "U.N. panel of experts .. say it is at least 95 percent likely that human activities ..are the main cause of warming "
.. see experts opinion rather actual science.
Hadcrut4 temperature trend since 1950 is 0.1 K/decade.
According to AR5 draft CO2 forcing since then increased by 1.2 Watts/m2, total forcing by 1.7 Watts/m2
CO2 contribution to warming is then 70% or only only 0.07 K/decade or 0.7K per century, well below even the recent low transient sensitivity estimates.
I would guess not to find this conclusion anywhere in the new report.
Do you suppose they are 95% confident of the cause of the fifteen year standstill?
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tomdesable
Why discuss rumours when with a little patience you can discuss the report itself? Think how silly you'll look if this is bullshit.
"Do you suppose they are 95% confident of the cause of the fifteen year standstill?"
kim
I doubt it. Losing the GLORY satellite meant that aerosol data has only been measurable from the ground. With increased aerosols from coal burning and volcanoes probably making a large contribution to the slowdown, that's a significant loss of information.
More "normal" weather.
http://www.bloomberg.com/news/2013-08-17/russian-regions-declare-emergency-amid-flood-seen-nation-s-worst.html
You seem slightly out of phase with your tuning knob, Entrophomme. The big boys are trying to blame the oceanic oscillations and the weak sun.
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Warming since the 1950s? I recall a period of cooling in the earlier global record, from about 1940 to 1975.
On WUWT just now, there is a reproduction of a graph that James Hansen showed to a Congress hearing some years ago, 1998 from memory, the one where they claimed they turned up the building's heaters.. There is, as remembered,, a most noticeable decline...
Then, the adjusters got to the data. GISS now shows an upward trend.
kim
Lots of choice here. Aerosols, increased vulcanism, weak solar cycles, ocean heat content changes, cloud, albedo changes, soot, disrupted jetstreams, wildfires, Arctic and Antarctic ice loss, ENSO, AMO, extreme weather and CO2 are all driving temperatures up or down simultaneously.
What we are seeing is the resultant of all these positive and negative effects. I doubt you'll get good answers on this until there has been opportunity to analyse the data in retrospect.
Geoff Sherrington
All the global temperature records; GISS, NCDC, Hadcrut and Berkeley show the same pattern. There is short term noise. On that is superimposed a roughly decadal solar cycle, a sixty year cycle which may be AMO and a long term warming trend of 0.6C/century.
If one group were fiddling their results it would show as divergent from the others, yet there's no significant difference between the four. Berkeley, in particular, was intended as an independant check on the other three. Starting from first principles, it was expected to debunk the rest and ended up in close agreement with them.
http://berkeleyearth.org/summary-of-findings
Richard Drake Aug 17, 2013 at 9:34 AM
Quite right. The authors of AR5 are in no sense experts. They’re gentlemen amateurs, appointed by governments to write a 3000 page opinion piece - unpaid - in their own time. They know nothing about the future temperature of the planet. They can’t predict the temperature increase in the next 87 years to the nearest five degrees, which is nearly ten times the increase over the past 87 years. They’re useless, by their own admission.In a sane world, Hegerl and her colleagues would be laughed out of the TV studio by an army of Andrew Neils. What will happen in reality come the publication of the report? Will Montford and Peiser be invited to debate with Hegerl and Bob Ward? That’s the important question.
Paul_K
"I know that a lot of people have been using it as such [ heat hiding in the oceans as a get out of jail card], but the truth is that the Otto et al study used the most aggressive (highest) estimates of ocean heat uptake possible - and they still found a TCR of 1.3 deg C and a modal value of ECS of around 2 deg C."
I agree that the highest observational estimate of ocean heat uptake was used in Otto et al 2013. However, for the record, that did not affect the TCR estimates at all, and it had the effect of increasing the ECS estimates compared to use of a lower ocean heat uptake estimate.
Also, all the TCR and ECS central estimates stated in Otto et al are medians (which equal the maximum likelihood estimates), not modes.
Reuters are out of order in citing the draft AR5 report before it has been finalised.
Firstly, the content may change between the draft and the final report, so citing the draft could lead to confusion. The statement they are referring to will probably be very carefully discussed in order to get it right before publication, and could be different to the version in the draft. Secondly, Reuters haven't given a direct quote, they seem to have just paraphrased, so they may not be conveying the meaning correctly. Thirdly, cherry-picking a phrase without the context of the rest of the report does not allow the reasons behind the statement to be checked.
The draft are clearly labelled "Do not cite, quote or distribute" on every page. One can only wonder why Reuters have explicitly gone against this request.
very good Richard -one can still hope the absolute stupidity of coming up with an uncomputed likelihood figure will be finally recognised and eliminated for good.
Now call me a cynic Richard but every politician under the sun knows this game, a leaked 'off the record' comment, precis, abstract etc and then when the leak is reported in the press, stand back, deny it and any responsibility and say it was only a draft, provisional, interim, untested.................
<,i>Testing the water, is hardly a new game, the UN is a political beast and the IPCC-AR5 ad infinitum - is primarily geo-politics and writ large, whatever anybody else says.
Entropic Man says:
"Lots of choice here. Aerosols, increased vulcanism, weak solar cycles, ocean heat content changes, cloud, albedo changes, soot, disrupted jetstreams, wildfires, Arctic and Antarctic ice loss, ENSO, AMO, extreme weather and CO2 are all driving temperatures up or down simultaneously."
Well, first off Entropic Man, I hardly think Spock and his vulcan buddies have anything to do with it. Second off, I'm pretty sure that CO2 levels have historically lagged temperatures, so I don't think they are driving temps. According to Wunsch, who I believe, temperatures drive CO2 levels, not the other way round. It gets hotter, oceans warm, they give off more CO2. I'm no scientist, but I've got that much memorized.
Live Long and Prosper dude.
Entropic Man says:
"Lots of choice here. Aerosols, increased vulcanism, weak solar cycles, ocean heat content changes, cloud, albedo changes, soot, disrupted jetstreams, wildfires, Arctic and Antarctic ice loss, ENSO, AMO, extreme weather and CO2 are all driving temperatures up or down simultaneously."
But don't worry - trust the models!
"Oh let us never, never doubt
What nobody is sure about" (Belloc)
So, Richard Betts, if the SPM comes up with just such a figure, what will we make of it? I kind of assume there is no scientific backing for stating a claim in such a way in the full report at whatever order of draft?
If there is, will some willing leaker just give us a sight of it?
Athelstan
The leak may well be for political reasons, but I very much doubt that it was from IPCC WG1 itself. It's more likely to be from a reviewer who wants to try to use it to support his/her own agenda. Very disappointing for confidentiality to be broken in this way.
Rhoda
If it's in the published SPM then you can be sure it's been thoroughly reviewed and debated to within an inch of its life :-)
omnologos
I don't see why likelihood statements are a bad thing. It's good to give an idea of levels of certainty / uncertainty. These can then be revised (either way) as more evidence becomes available.
Richard Betts points out: "It's good to give an idea of levels of certainty / uncertainty. These can then be revised (either way) as more evidence becomes available."
So if the level of certainty were to be shown to have increased to 95%, in the face of a very distinct flattening (or even falling off, some might say) of surface temperatures this century that nobody seems able to explain with any degree of certainty, then what ought one to conclude?
That they have developed an even greater understanding of the causes of 20th C warming without being able to explain what has been going on more recently?
And that they can say unequivocally how much heat has been going into (or out of) the ocean depths since 1950?
Hi matthu
Whatever the likelihood statement in the final report, the reasons behind it will be explained clearly. I'd encourage readers to look at the report itself and not just the headlines in the media.
Incidentally, the IPCC statement on the recent leak and Reuters article is here. They say:
Well, for the sake of moderate scientists everywhere, lert's hope they show a bit more humility.
tomdesabla
In the context of Milankocich cycles temperature drives CO2 in positive feedback loops which amplify the effect of the insolation change. That's why interglacials are 5C warmer than glacial periods, even though the insolation change is only enough for 1C of warming.
Thre have been a couple of natural occasions on which CO2 has led temperature, notably in the recovery from snowball earth episodes. We now have a third, in which CO2 stored up to 400 million years ago is being rapidly released. I see no reason why a CO2 led change will not produce the same positive feedback as a temperature led change.
Richard - I understand I have been around a few more blocks than you have. Perhaps schooling in the 1970s was very different, and we have learned a different set of mathematics.
In the one I am familiar with, a figure like "95%" is always derived from some computation. Why not 93.4%, or 96.7%? Why not 15.4%?
If we wanted to say "very likely", we said "very likely". And if we wanted to shoot out some guesswork, we wouldn't be professionals.
omnologos
Estimating quantitative likelihoods is just the standard Bayesian approach.
Have you read Nate Silver's book 'The Signal and the Noise'? He makes a very good case for making quantitative estimates of probability in all sorts of forecasts, including baseball betting, poker and weather forecasting. (Incidentally, Mike Mann didn't like his climate chapter - admittedly it was somewhat oversimplified, but I think it still makes interesting reading.)