12:24 pm - December 14th 2009
So, at last, the Mail on Sunday has waded into the furore surrounding the hacked CRU emails with a special investigation, bringing out its big guns, David Rose, who is highly regarded as a journalist and has a solid track record in serious reporting and investigations, to write up the story.
For all his well-deserved reputation as a serious journalist, Rose, it must be said, also has previous form for being taken in by sources he believed to be reliable at the time but which then proved to have been feeding him disinformation. In this case the disinformation in question related to alleged links between Saddam Hussein and Al Qaeda, which Rose fell for hook, line and sinker. To his credit Rose did eventually come clean and admit to having been duped, expressing his regrets in very strong and, in regards to the role of some of his sources.
The point I’m making here is that even a very good journalist is only ever going to be as good as his sources, and in the case of Rose’s investigation his choice of sources are letting him down very badly indeed.
Misquoting Roger Pielke Jr.
In the article Roger Pielke Jr is presented by Rose as a credible (i.e. non-skeptical) climate scientist who fully accepts the reality of anthropogenic global warming and a strong advocate for action who has, nevertheless, been highly critical of the scientists at the centre of this issue:
Pielke’s verdict on the scandal is damning.
‘These emails open up the possibility that big scientific questions we’ve regarded as settled may need another look.
‘They reveal that some of these scientists saw themselves not as neutral investigators but as warriors engaged in battle with the so-called sceptics.
‘They have lost a lot of credibility and as far as their being leading spokespeople on this issue of huge public importance, there is no going back.’
Pielke may well stand by his opinions of the scientists but, as he disclosed on his own blog within hours of the article’s publication, not by the suggestion that any of the big scientific questions relating to AGW may need to be re-examined.
I just saw your story in the Daily Mail and a small correction is needed. You quote me as saying:
“These emails open up the possibility that big scientific questions we’ve regarded as settled may need another look.”
What I said was:
“While these emails open up the possibility that some scientific questions we’ve regarded as settled may need another look, time will tell and the implications for science are not the most important aspect of the emails.”
The point was that while I am agnostic about the implications for science, leaving that to others, I am certain that the emails have broader implications for the credibility and legitimacy of certain quarters of climate science. Based on what I’ve seen, I do not believe that any “big scientific questions” are implicated by the emails.
So, what Pielke actually suggested was that while the CRU emails raise, for him, questions about the credibility of paleoclimatology, which provides only a small part of the evidence for climate change, he’s content that this does not challenge the credibility of AGW theory as a whole, which is what the misquote implies. Pielke, as you can see if you follow the link, has asked for a correction, to which Rose has responded by indicating that he’s forwarded that request to the ‘appropriate editor’ at the Mail.
Whether he gets his correction or not, given that this is a Mail we’re talking about, could be another matter entirely – it hasn’t happened yet.
Dishonesty in the Southern Hemisphere
Later in the article, after noting, correctly, that climate scientists have to make adjustments to proxy data from sources such as tree rings and ice cores to correct for anomalies that would distort their findings, Rose adds the following:
But can we trust the way such ‘adjustments’ are made?
Last week, an article posted on a popular climate sceptic website analysed the data from the past 130 years in Darwin, Australia.
This suggested that average temperatures had risen there by about two degrees Celsius. However, the raw data had been ‘adjusted’ in a series of abrupt upward steps by exactly the same amount: without the adjustment, the Darwin temperature record would have stayed level.
The ‘popular climate sceptic website’ is, in this case, that of Anthony Watts, the TV weatherman who famously responded to a video by Peter Sinclair that debunked his claim that the NOAA’s US Surface Station record was unreliable, not by acknowledging that he was in error but by firing off claims of copyright infringement to You Tube in an effort to suppress the video. As questions about scientific effects are central to the debate surrounding the CRU emails, its well worth remembering that deniers like Watts routinely behave as if they those same standards do not apply to their own ‘research’.
The claims relating to the Darwin temperature record were made by Willis Eschenbach, who deploys a ‘trick’ of his own to make the warming trend in the data relating to Darwin ‘disappear’, the same trick used a couple of weeks earlier by a ‘sceptic’ group calling itself the New Zealand Climate Change Coalition, that of treating data from different weather stations as if they were from the same site.
Had Rose bothered to carry his investigations further that Watts’ site he might have found that the NZ CSC’s trick was rapidly debunked, while Essenbach’s attempt to pull out the same trick on the data from Darwin lasted less than 24 hours before it too was exposed as a fraud.
(UPDATE – even if Rose failed to scan a few independent blogs for responses to Eschenbach’s piece on the Darwin temperature record, he might have noticed this take down by The Economist).
The Divergence Problem and the Medieval Warm Period
The heart of Rose’s ‘investigation’ is a discussion of the contents of some of the CRU emails.
I’ve covered this already but to quickly recap, the divergence problem relates to the proxy data derived from tree rings which is used to reconstruct temperatures from the pre-industrial era, i.e. before the advent of reliable meteorological records and the quickest way to explain it is simply to show it to you using this graph:
The data in red comes from the instrumental record and shows the average global temperature since 1850 as derived from measurements taken by weather stations, while the data in blue shows the proxy record compiled from tree ring data by Keith Briffa, which is known as ‘Briffa 99′ and for each I’ve added polynomial trend lines so you can see exactly what’s going on.
As you can see, from around 1960 onwards, the two graphs diverge sharply – the instrumental record keeps rising, which is consistent with global warming, but the proxy record shows an apparent downward trend that much more pronounced than the upward trend on real temperatures. Something is clearly wrong with the proxy record from 1960 onwards as it clearly doesn’t show what we know to be actually happening, hence the divergence problem.
The core of the current controversy stems from the omission of the proxy data from 1960 onwards from the ‘hockey stick’ graph which appeared in the 2oo1 IPCC report and, more importantly, the failure of the IPCC to acknowledge that this data had been excluded. The graph that did appear in the report substituted the data from the instrumental record and omitted the proxy data from 1960 onwards, ensuring that the correct trend was shown but did not admit to the use of this ‘trick’. This is the ‘decline’ that the scientists refer to when they talk about ‘hiding the decline’ in the hacked emails.
If you look at what various skeptics and deniers are saying about this graph at the moment you’ll find three common claims being made.
First, some deniers claim that the proxy data shows that the global climate is actually cooling and its this that the scientists were deliberately hiding. This claim is complete bullshit.
The second claim is that the divergence problem, which has been extensively researched since it was discovered in the late 1990’s, somehow invalidates the entire hockey stick graph because it proves that the entire proxy reconstruction is in error.
The short answer to that claim is ‘no, it doesn’t’. It does raise some legitimate questions as to whether and what extent any of the confounding factors that are thought to contribute to the observable divergence problem in the post-1960 data may be present in the pre-industrial reconstruction, meaning that there is a need for much more research into those questions, but it remains the case that a series of reconstructions produced after MBH98/99 and Briffa 99 using different proxies all support the reconstructed temperature trends that were shown by both models for the pre-industrial period, all of which suggest that despite there being known, and acknowledged, methodological flaws in the compilation of these earlier reconstructions, the flaws did not unduly affect their outcome.
How warm was the Medieval Warm Period?
The third issue relates to one very specific part of the reconstruction, which is called the ‘Medieval Warm Period’ (MWP). This is period of seemingly natural warming in the Northern Hemisphere, and particularly in Northern Europe, the North Atlantic and North American, of around 300-400 years centred on the first century of the first millennium (1000-1100AD). It encompasses, amongst other things, the period during which we know that the Vikings embarked on several significant voyages of discovery, reaching Iceland, Greenland (which got its name, which seems incongruous today, during this period) and North America.
Amongst some sceptics, including McIntyre and McKitrick, the contention is that the natural warming that occurred during parts of the MWP was as pronounced as it is today, and that this disproves that the claim, made by climate scientists, that the current level of warming is unprecedented in recent human history (i.e. the last 1500-2000 years or so). This line of argument is reflected in Rose’s article in this passage:
For example, some suggest that the ‘medieval warm period’, the 350-year era that started around 1000, when red wine grapes flourished in southern England and the Vikings tilled now-frozen farms in Greenland, was considerably warmer than even 1998.
Of course, this is inconvenient to climate change believers because there were no cars or factories pumping out greenhouse gases in 1000AD – yet the Earth still warmed.
Some tree-ring data eliminates the medieval warmth altogether, while others reflect it. In September 1999, Jones’s IPCC colleague Michael Mann of Penn State University in America – who is now also the subject of an official investigation –was working with Jones on the hockey stick. As they debated which data to use, they discussed a long tree-ring analysis carried out by Keith Briffa.
Briffa knew exactly why they wanted it, writing in an email on September 22: ‘I know there is pressure to present a nice tidy story as regards “apparent unprecedented warming in a thousand years or more”.’ But his conscience was troubled. ‘In reality the situation is not quite so simple – I believe that the recent warmth was probably matched about 1,000 years ago.’
The suggestion here is that scientists at the CRU may have been manipulating the proxy data, as much by omission as anything else, to minimise the apparent scale of the MWP as it appeared in, at least, Briffa’s proxy in an effort to lead people to the conclusion that scientists are concealing a crucial piece of evidence which would indicate that there is nothing particulaly unusual or unprecedented about current warming trends and they are, if natural in origin then, at least, within the scope of past trends which didn’t trigger a global climate catastrophe.
There are, however, two key facts about the evidence relating to the proxy data, the divergence problem and MWP that you won’t see cited on the websites of ‘skeptics’ like McIntyre and McKitrick in conjunction with their musings on the meaning of these emails.
One of these is that one of the possible implications of the divergence problem that is being heavily investigated at the moment is that some of the confounding factors that are thought to account for the anomalous decline in the post-1960 trend line would, if found to be active in the pre-industrial reconstructions, have the effect of causing scientists to over-estimate the degree of warming that occurred during the Medieval Warm Period. The MWP may not have been quite as warm as those skeptics who are relying on it to debunk AGW, or at least cloud the issues around it, think.
The second is that, at least some of the emails that are being put forward as being the most damaging evidence against the CRU researchers and other paleoclimatologists are anything up to ten years old, and both the science and its evidence base have moved on considerably in the intervening years, particularly in regards to understanding the scope and [lack of] significance of the MWP.
So what you won’t see are these two plots of global temperature patterns, one from the MWP, the other covering the period from 1998-2008.
As you can clearly see from the two plots, the MWP was not a global phenomenon. It was, in fact, localised on the North Atlantic and had very little impact on overall global temperatures, not least due to cooling in the Southern Hemisphere, unlike the current warming pattern which shows temperatures rising almost everywhere but for Eastern Pacific. As such, plots of raw data from exclusively Northern Hemisphere proxies, the data that McIntyre has been trying to obtain and would no doubt have presented as evidence against AGW theory, will not provide an accurate picture of global warming during the MWP because the warming trend was localised on one specific region.
Much of the chatter on ‘skeptic’ websites of late has focussed on putting interpretations on comments within the CRU emails which suggest a deliberate conspiracy to conceal or minimise evidence relating to the MWP. One email, in particular, makes a reference to the need to ‘contain’ the MWP, which deniers have interpreted as evidence that scientists have been attempting to make the temperature changes during that period appear small than they actually were as part of their global AGW conspiracy. i.e. that they we seeking to ‘contain’ the scale the warming that occurred during that period on the reconstruction graphs.
In reality, this comment refers to the need to ‘contain’ the MWP temporally – at the time the email was written, the available reconstructions stretched back only as far as 1000AD and, began, started during the Medieval Warm Period, making it impossible to see the full trend. The need to ‘contain’ the MWP, in this case, meant only the need to extend the scope of the reconstruction back further in time so that both the beginning and end of the MWP could be seen on the graph, it had nothing whatsoever to do with the scale of the warming evident during that period other than in the sense that it could not be fully assessed without a suitable reference point right at the very start of the period.
The Inconvenient Truth
All of the additional information I’ve provided here, in relation, to Rose’s article is sourced from the public domain and most of it, with the exception of Pielke’s complaint about being misquoted, was available to Rose before his article was published, if only he’d spent 10-15 minutes checking his sources using nothing more complicated than Google.
As a result his ‘special investigation’ fails to live up to its billing.
More to the point, it – like almost everything else published by the mainstream press since these emails emerged – completely ignores the central ethical dilemma that climate scientists working at the CRU have faced over the last ten years.
What do you do when faced with a barrage of requests for raw data when you know full well that the people making the requests will misuse that data, if its given to them, to fundamentally misrepresent your work and publish a false and entirely misleading picture of the evidence?
What is the correct, ethical, answer to that question?
And if we’re going to make a big deal of the apparent ethical shortcomings of the CRU scientists, then should we not also apply those same standards to their critics, most of whom have already been caught out for publishing misleading claims?
'Unity' is a regular contributor to Liberal Conspiracy. He also blogs at Ministry of Truth.
· Other posts by Unity
Story Filed Under: Blog ,Environment ,Media ,Science
Sorry, the comment form is closed at this time.
Reactions: Twitter, blogs
- Liberal Conspiracy
@libcon New Post – The Inconvenient Truth about David Rose's 'Special Investigation' – http://bit.ly/6E6UzC
- Sunder Katwala
Unity with some sense on climate graphs > @libcon Inconvenient Truth about Mail on Sunday 'Special Investigation' http://bit.ly/6E6UzC
- sunny hundal
- Matt Lodder
On media coverage of climate science. RT via Liberal Conspiracy http://bit.ly/6E6UzC
- Mark Taylor
Shared item: The Inconvenient Truth about David Rose’s ‘Special Investigation’: So, at last, the Ma.. http://tinyurl.com/yegaplr
- Claire Spencer
A million times WOW at this excellent @libcon post 'The Inconvenient Truth about David Rose’s ‘Special Investigation’' http://bit.ly/7r5Yk0
- ben goldacre
The Inconvenient Truth about David Rose’s "Special Investigation": Unity was also ace on @NadineDorriesMP http://bit.ly/5EfnOJ
- Adrian Sevitz ?
I love the detail this article goes into on the Q's raised by the CRU emails on climate change. http://bit.ly/5EfnOJ
- sunny hundal
Greenies! [@christineottery @adamvaughan_uk @TheGreenParty @CarolineLucas] You may be interested in this: http://bit.ly/7r5Yk0
RT @sevitzdotcom: I love the detail this article goes into on the Q's raised by the CRU emails on climate change. http://bit.ly/5EfnOJ
- Christine Ottery
- Paula Thomas
RT @bengoldacre: The Inconvenient Truth abt David Rose’s "Special Investigation": Unity was also a1 on @NadineDorriesMP http://bit.ly/5EfnOJ
- Bren Tierney
@mmfa re 'Climategate' if you've not yet seen this, it's required reading http://www.liberalconspiracy.org/2009/12/14/9845/
- Brendan Meachen
On media coverage of climate science. RT via Liberal Conspiracy http://bit.ly/6E6UzC (via @mattlodder)
- john rickards
I'm half cut so I can't remember who I'm RTing, but this is terribly good fun as an ex-environmental engineer: http://is.gd/5nlKt
- The Daily Quail
Not just any ordinary Mail article either, but the one that's roundly demolished here: http://bit.ly/7zqJi8
- Ian G. Stimpson
If you are not yet bored of the climate debate here is IMHO a calm, rational, balanced overview of the recent issues http://bit.ly/7r5Yk0
- brittany hughes
Liberal Conspiracy » The Inconvenient Truth about David Rose's …: When they do so, they have to show thei.. http://bit.ly/875VgQ
- Chris Rowan
Good overview of CRU e-mail palava. Yes I know, but this one has some nice figs (via @hypocentre) http://bit.ly/7r5Yk0
- Mary Beith
RT @Allochthonous: Good overview of CRU e-mail palava. Yes I know, but this one has some nice figs (via @hypocentre) http://bit.ly/7r5Yk0
- Chris Townsend
Liberal Conspiracy » The Inconvenient Truth about David Rose’s ‘Special Investigation’: http://bit.ly/71q5bm via @addthis
- Zone5 » Checkmate for the Climate Change Deniers
[...] Brilliant debunking of the leaked emails by Unity here. [...]
- john wyke
the kerfuffle about the climate change email malarky well explained… http://icio.us/wsk34k
- Moon Howler
RT @hypocentre If you're not yet bored of the climate debate here is a rational overview of the recent issues http://bit.ly/7r5Yk0
- Disneyland Paris: marks out of ten from a six-year-old | Donald's Archive 2.0
[...] can tell us all sorts of things. They can be very complicated. Or they can be simple. But they are best when in the raw. So, here, uneditorialised, unedited, in [...]
Sorry, the comment form is closed at this time.