Another climate splash in the Mail on Sunday

David Rose has a big splash in the Mail on Sunday, covering a leaked version of the Summary for Policymakers, Nic Lewis's report on the Met Office model and taking a well-aimed potshot at Bob Ward to boot.

They recognise the global warming ‘pause’ first reported by The Mail on Sunday last year is real – and concede that their computer models did not predict it. But they cannot explain why world average temperatures have not shown any statistically significant increase since 1997.

Update on Sep 15, 2013 by Bishop Hill

The Met Office has issued a holding response to the Mail article. Significantly, no mention is made of Nic Lewis's criticisms of their model.

Comments

[HaroldW]

entropic man: "The confidence limits include anything from a rise of 0.1C in the last decade, through stasis to a 0.1C cooling."
Ah, then you accept that the multi-model mean of AR4, predicting 0.2C/decade (actually about 10% higher if my memory serves, which it often doesn't), is effectively disproven. Even more so the models at the high end of that grouping, such as HadGEM2.

[entropic man]

"Ah, then you accept that the multi-model mean of AR4, predicting 0.2C/decade (actually about 10% higher if my memory serves, which it often doesn't), is effectively disproven. Even more so the models at the high end of that grouping, such as HadGEM2.

Sep 16, 2013 at 5:05 PM | HaroldW"

Current annual means are close to the lower bound of the AR4 model predictions' 95% confidence range. Once the 95% confidence limits of the annual and model means no longer overlap, then I would accept the model predictions as disproven. That will take about another 0.1C of divergence.

If the current trend in annual mean temperatures continues that will be around 2017/18.

I'm not inclined to jump to conclusions. Wre'll know then which of us was right.

[HaroldW]

entropic man -
You are being too conservative by waiting until the two confidence ranges fail to overlap. I commend to you Lucia's analysis of AR4 predictions vs. observations, especially the final section entitled "So can you learn anything from short trends?"

[Rob Burton]

Sep 16, 2013 at 1:08 PM | entropic man

Surely everyone who has read Bishop Hill for more than a few minutes would know Don Keiller's academic qualifications. If you're not sure you could always try a search engine such as Google. As an aside, I studied postgrad climate science at Reading Meteorology department and think the CAGW CO2 hypothesis is useless.

[Richard Betts]

David Rose

In your Mail on Sunday article, your fourth paragraph says:

Yet the leaked report makes the extraordinary concession that the world has been warming at only just over half the rate claimed by the IPCC in its last assessment, published in 2007.

Please could you clarify the numbers you used for the rate at which "the world has been warming", in AR4 and the draft AR5?

Thanks!

Richard

[diogenes]

...just wondering what entropic man has to gain by his strenuous defence of crap science? Is he paid by Big Oil?

[entropic man]

HaroldW

I am conservative. You used the word " disproved" and for that you need to reach 95% confidence or 5% confidence. I regard Lucia's analysis as lacking rigour. She accepts or discards trends over timescales and standard deviations I see as statistically insufficient.

Rob Burton

I am familiar with Dr. Keiller from past papers, though I had not made the connection between the biochemist and the climate campaigner until today.

For family reasons I remain incognito. It seems unsporting to Google other people when they can't Google me. All they'd get anyway is a retired science teacher with no public profile and no publications apart from a couple of letters in the Daily Telegraph and New Scientist.

I'm interested that you regard CO2 as not a climate driver. Perhaps Bishop Hill will lift his ban on radiative physics and let us discuss the evidence further sometime.

[entropic man]

diogenes

In old age many skills become "use it or lose it".

Debating science here helps keep my mind active, and I enjoy it. As Rhoda points out, there's probably a bit of the pdagogue still left within.

Would anyone be daft enough to pay me? I think not.

[diogenes]

smiles at entropic man --

it seems that your ravings keep a few people here amused

[HaroldW]

entropic man:
"I regard Lucia's analysis as lacking rigour. She accepts or discards trends over timescales and standard deviations I see as statistically insufficient."

In her analysis, Lucia derives a standard deviation which is appropriate to the timescale being considered. A short timescale implies a large uncertainty and corresponding difficulty for the difference (between observation and prediction) to reach a level of 95% falsification. It is, in her opinion and mine, possible to make judgments over intervals shorter than (say) 30 years, if one includes such an adjustment. You are, of course, entitled to your assessment.

But consider this. If a measurement has two uncorrelated error sources, with respective standard deviations of sigma_1 and sigma_2, the standard deviation of the measurement is sqrt(sigma_1^2 + sigma_2^2). Not sigma_1 + sigma_2. Your approach effectively adds the deviations arithmetically rather than in root-sum-square fashion.

[entropic man]

HaroldW

It's too late at night for such thinking. I'll get back to you on that one.

[entropic man]

it seems that your ravings keep a few people here amused

Sep 16, 2013 at 10:34 PM | diogenes

It seems that the ravings here keep me amused.

[HaroldW]

Touché.

[richard verney]

"...If the current trend in annual mean temperatures continues that will be around 2017/18.

I'm not inclined to jump to conclusions. Wre'll know then which of us was right."

Sep 16, 2013 at 5:38 PM | entropic man
//////////////////

Even the Met Office are predicting no retrun to warming before 2017/18 so they are envisaging that the models will be falling out of the 95% conficence range.

Of course, we will not know for sure until 2017/18 but it is clear to most objective observers that the models do a very poor job at projecting reality.

[Martin A]

I think your second point disproves the premise in your first point. The Met Office's principle product is not "propaganda", it's science. Science should be critiqued and discussed in order for it to progress.
(...)
Sep 15, 2013 at 11:42 PM Richard Betts

"It’s now clear that man-made greenhouse gases are causing climate change. The rate of change began as significant, has become alarming and is simply unsustainable in the long-term."

Met Office Publication

[Manfred]

On a positive note, the Met Office let through a number of quite critical comments, including one from Nic Lewis.

http://metofficenews.wordpress.com/2013/09/15/met-office-in-the-mail-on-sunday/

That would be unthinkable at the German PIK, for instance. Or the homerpage of the EU commissioner Heedegard. Or the homepage of the BBC.

But the glorious British democratic spirit allows sometimes a culture of discussion still to slip through the newly erected iron curtains.

[Dolphinhead]

The Mail on Sunday have added a 'Clarification' to the original article

Clarification
An original version of this article sought to make the fairest updated comparison with the 0.2C warming rate stated by the IPCC in 2007.
It drew on the following sentence in the draft 2013 summary: ‘The rate of warming over the past 15 years… of 0.05C per decade is smaller than the trend since 1951, 0.12C per decade.’ This would represent a reduction in the rate of warming by a little under one half.
But critics argued that the 0.2C warming rate in the 2007 report relates only to the previous 15 years whereas the 0.12C figure in the forthcoming report relates to the half-century since 1951. They pointed out that the equivalent figure in the 2007 report was 0.13C.
This amended article compares the 0.05C per decade observed in the past 15 years with the 0.2C per decade observed in the period 1990-2005 and with the prediction that this rate per decade would continue for a further 20 years.

The title to the article now reads

World's top climate scientists confess: Global warming is just QUARTER what we thought - and computers got the effects of greenhouse gases wrong

[Richard Betts]

Somebody at the Mail on Sunday clearly has a very mischievous sense of humour!

[Dolphinhead]

Yes indeed Richard but you can't say you didn't have it coming.

[flaxdoctor]

It's even worse than we thought! (TM)

[@HG54]

[Apologies, I initially posted this in the wrong thread]

Last night the Mail changed the headline from "World's top climate scientists
confess: Global warming is just HALF what we thought ..." to "World's top
climate scientists confess: Global warming is just QUARTER what we thought
...".

The paper says

"This amended article compares the 0.05C per decade observed in the past 15
years with the 0.2C per decade observed in the period 1990-2005 and with the
prediction that this rate per decade would continue for a further 20 years."

http://dailym.ai/1aS4roS

[Richard Betts]

Dolphinhead

Actually, I find the revised article less irritating than the original, even though I disagree with the new headline even more, because David Rose has removed a factual error.

I still disagree with his interpretation of the numbers that he is now quoting - I don't think short timescales tell us much about the real rate of anthropogenic climate change - but this is now in the realms of opinion instead of misrepresentation of facts.

The thing that caused me to object was not his actual conclusion, but how he arrived at it.

[Dolphinhead]

Richard Betts

"I don't think short timescales tell us much about the real rate of anthropogenic climate change"

Which period should we look at then to detect the fingerprint of ACC?

Moreover I would argue that a lack of warming for a period of some 15+ years does tell us a great deal about the climate and by extension about ACC. it is a factor that has to be taken into account. It impacts on what you guys call 'climate sensitivity'. It tells us what is happening in the real world as opposed to the imaginary world of the MO computer models.

If we are to believe the MO's predictions/forecasts/projections for the next 5 years, we will have a period of some 20+ years of no warming. If the MO stands by its forecast are you saying that 20 years tells us nothing about the climate?

Any reasonable person would conclude the models and those promoting the models are wrong. You can argue all day whether they are wrong by half or a quarter or whatever but they are wrong. And the real point here Richard, as you know, is the harm that has been done to the businesses and people of our country as a result of the MO's misplaced confidence in these models of dubious value.

In spite of the many pleas for the MO to change its ways it seems that it wants to continue to live in the make believe world of its models rather than the real world.

[entropic man]

Dolphinhead

Unfortunately the "reasonable person " you refer to does not seem to understand satistics.

[Dave Salt]

entropic man (Sep 18, 2013 at 6:14 PM) you say "Unfortunately the "reasonable person " you refer to does not seem to understand satistics", which I suppose implies that climate scientists do... well, 97% of them, anyway :-)

[entropic man]

David Salt

They know enough not to try and predict long term trends from too few years of noisy data.

Over and over again sceptics make this mistake. "No warming for 15 years" is a favourite. There is year-on-year stochastic variation of about +/- 0.1C in the temperature record. To pick a long term trend out of the noise needs a number of years of data. At latter 20th century warming rates this needed 20 years of data to reach 95% confidence in the trend.

Post 2002, which is the inflection point I usually use, we have a decade's data and the noise level still obscures the recent trend. The statistics are good enough that we can say that there is no more than a 5% probability of more than 0.1C warming or no more than a 5% probability that cooling exceeded 0.1C. Anything between is possible.

I always find it ironic that so many sceptics deride the quality of climate science while demonstrating such low standards themselves. I have read "no warming for 15 years" more times than I can count, but not once has anyone given confidence limits to go wih it.

[Dave Salt]

entropic man (Sep 18, 2013 at 11:47 PM), you mix-up a number of issues when trying to make your point.

Yes, taking 2002 as your 'inflection' point strengthens your case for too short a data set but is somewhat arbitrary: I'm sure a case could be made for taking 2000 or even 1998 (http://www.woodfortrees.org/plot/hadcrut4gl), which supports "no warming for 15 year" statements but, admittedly, doesn't reach your required level of confidence. More interestingly, moving back the start date for the so-called 'pause' also shortens the late-20th Century warming phase, especially if you judge the 'inflection' point for its start as being 1980 or even 1982.

I guess all I'm saying is that arguing over 'statistical confidence' is a very tricky subject in this respect and that both sides are guilty of cherry-picking data to support their argument... now, remind me again, just how do the IPCC justify their 'level of confidence' that recent warming is predominantly anthropogenic
(http://www.ipcc.ch/pdf/supporting-material/uncertainty-guidance-note.pdf)?