A couple of days ago one of Hot Topic’s denialist commenters triumphantly waved a UK Sunday Times article claiming that the IPCC had erred not only in relation to the likely rate of melting of Himalayan glaciers but also in linking global warming to an increase in the number and severity of natural disasters.
I had a quick look at the IPCC report referred to and responded by pointing out that the section pointed to by the Sunday Times wasn’t about the frequency of extreme events but about their costs.
I think the matter is worth longer treatment than I gave it there, because it is an example of shocking carelessness, if not deliberate misrepresentation, passing itself off as responsible journalism on climate change. The Sunday Times article was written by Jonathan Leake, their science and environment editor.
We’ve caught the IPCC at it again, he virtually proclaims. The IPCC has based its claims that natural disasters are increasing as a result of global warming on an unpublished report that had not been subjected to routine scientific scrutiny. On this slender basis developing nations have demanded compensation from rich nations and Ed Miliband, Barack Obama and Gordon Brown have been led into exaggerated statements.
It was news to me that the whole question of the frequency of severe events rested on a single report, and it rapidly becomes apparent in Leake’s report that he is confused (I hope not disingenuous). Here is what he writes:
“The new controversy also goes back to the IPCC’s 2007 report in which a separate section warned that the world had ‘suffered rapidly rising costs due to extreme weather-related events since the 1970s’.
“It suggested a part of this increase was due to global warming and cited the unpublished report, saying: ‘One study has found that while the dominant signal remains that of the significant increases in the values of exposure at risk, once losses are normalised for exposure, there still remains an underlying rising trend.’”
Costs? Losses? This must surely be from Working Group II of the IPCC which deals with the impacts of climate change, not from Working Group I which deals with the physical science. And so it proved. The study he talks about is by Robert Muir-Wood, of the London consultancy Risk Management Solutions. It is referred to in a short section on economic and insurance losses, part of a longer section on disasters and hazards. The inference that this paper is the basis of the IPCC’s findings on the frequency and severity of natural disasters is simply ridiculous. Here is what the IPCC says of Muir-Woods paper:
“A global catalogue of catastrophe losses was constructed (MuirWood et al., 2006), normalised to account for changes that have resulted from variations in wealth and the number and value of properties located in the path of the catastrophes, using the method of Landsea et al. (1999). The global survey was considered largely comprehensive from 1970 to 2005 for countries and regions (Australia, Canada, Europe, Japan, South Korea, the USA, Caribbean, Central America, China, India and the Philippines) that had centralised catastrophe loss information and included a broad range of peril types: tropical cyclone, extratropical cyclone, thunderstorm, hailstorm, wildfire and flood, and that spanned high- and low-latitude areas.
“Once the data were normalised, a small statistically significant trend was found for an increase in annual catastrophe loss since 1970 of 2% per year (see Supplementary Material Figure SM1.1). However, for a number of regions, such as Australia and India, normalised losses show a statistically significant reduction since 1970. The significance of the upward trend is influenced by the losses in the USA and the Caribbean in 2004 and 2005 and is arguably biased by the relative wealth of the USA, particularly relative to India.”
A restrained statement, I’d have thought, and certainly staying firmly within the topic of costs, not using the Muir-Wood paper as a basis for evidence on the wider question of increased frequency of severe events. There are statements in many places in the IPCC report about changes in extremes and disasters, and it is absurd to treat this one section and this one paper as the basis of what it has to say. How on earth does a journalist carrying the responsibility for science and environment on a major newspaper not know that? I was pleased to see the IPCC issue a statement on Monday firmly refuting the Sunday Times article as misleading and baseless. The first point their statement makes is:
“[The Sunday Times article] incorrectly assumes that a brief section on trends in economic losses from climate-related disasters is everything the IPCC Fourth Assessment Report (2007) has to say about changes in extremes and disasters. In fact, the Fourth Assessment Report reaches many important conclusions, at many locations in the report, about the role of climate change in extreme events. The assessment addresses both observations of past changes and projections of future changes in sectors ranging from heat waves and precipitation to wildfires. Each of these is a careful assessment of the available evidence, with a thorough consideration of the confidence with which each conclusion can be drawn.”
(A convenient summary of what Working Group I has to say may be seen in their Frequently Asked Questions section . The question ‘Has there been a change in extreme events?’ is responded to on p.107, and the question ‘Can Individual Extreme Events be Explained by Greenhouse Warming?’ on p.119. Both answers are restrained and cautious.)
But even on the matter of trends in economic losses and disasters the Sunday Times has grossly misrepresented the IPCC, as Monday’s IPCC refutation adds:
“The second problem with the article in the Sunday Times is its baseless attack on the section of the report on trends in economic losses from disasters. This section of the IPCC report is a balanced treatment of a complicated and important issue. It clearly makes the point that one study detected an increase in economic losses, corrected for values at risk, but that other studies have not detected such a trend. The tone is balanced, and the section contains many important qualifiers. In writing, reviewing, and editing this section, IPCC procedures were carefully followed to produce the policy-relevant assessment that is the IPCC mandate.”
The full section is here on p.110 if you want to check the veracity of that judgement.
The Sunday Times article is simply untrue. It is lazy, sloppy journalism at best, deliberate misinformation at worst. It has been taken up trumphantly by the denialist world and reported widely and uncritically by other newspapers. I hope the paper is ashamed of what it has achieved, but I fear it will be rejoicing at the attention it has gained.
Leake needs to be watched. In a TimesOnline piece dated 29/11/2009, “Climate Change Data Dumped”, he misrepresented background information from UEA CRU’s data availability page as comments made by UEA scientists in response to the the email file theft.
The background info was at least three months older than that event.
This,as readers will remember, was part of a smear campaign that UEA CRU had “confessed/admitted” to “losing/destroying” “raw/original” data. 90% of contridiots still believe this.
Was interested to see Pielker Jr’s response at http://rogerpielkejr.blogspot.com/2010/01/ipcc-statement-on-trends-in-disaster.html
Simon, I tried to follow Roger Pielke’s typically opaque post. I disagree completely with his assertion that the Sunday Times article is not about the general theme of extremes. That is what the article is mostly about, as is quite clear from its opening paragraph:
“THE United Nations climate science panel faces new controversy for wrongly linking global warming to an increase in the number and severity of natural disasters such as hurricanes and floods.”
It gets tangled with Pielke’s major concern about the costs of disasters, and Pielke has a longstanding grievance over the IPCC handling of this question. Bob Ward’s article on the matter in Tuesday’s Guardian sheds more light for me than I could elicit from Pielke’s blog.
Ward’s conclusion: ” What is clear is that it would be wrong to think of this as another mistake by climate researchers. In fact it looks more like a blatant attempt to dig up an old academic row in order to create the impression of an IPCC under siege.”
I’m left wondering whether Leake’s ill-considered Sunday Times article was sparked by Pielke.
Yes the Bob Ward article is of interest.
What I don’t understand is Ward’s claim that the Muir-Wood’s paper he quotes (and the descendant of the paper used by the IPCC in making its claims) somehow implies that Piekle’s claim is wrong. Ward implies that Muir-Wood et al somehow presents peer reviewed evidence of an association between climate warming and increased costs
But the condensed summary of Muir-Wood’s paper (viewable free at Google books) ends “We find insufficient evidence to claim a statistical relationship between global temperature increases and normalised catastrophe losses.”
This seems to me to be what Piekle was saying, and appears to be at odds with the IPCC report in respect of this paper’s earlier unpeer reviewed incarnation.
By the time you get to the penultimate couple of paragraphs of Ward’s piece you suddenly realise that he knows he’s been pulling a fast one. Until I looked at the primary sources I sort of couldn’t work out why he was suddenly talking about “The absence of a ‘statistically significant’ trend … ” (nor for that matter why the term was in quotes – is there another kind of trend he could be referring to in this kind of science?).
So enjoy the commentary from the Comms Director of a research institute but treat with care.
I haven’t looked closely at this whole issue but found http://www.gfdl.noaa.gov/bibliography/related_files/jms0701.pdf worth a read – even though I imagine things have moved on a bit.
http://www.timesonline.co.uk/tol/news/environment/article7003622.ece
C3Po, we have already had the timesonline article drawn to our attention by Mikh on this thread. You can see an exchange of comments there.
But why was the Muir-Wood statement published as an authoritative contribution to WG2 – although it was not peer-reviewed (which might not matter except that the IPCC has repeatedly insisted that it won’t touch anything not so blessed) and clearly wrong?
Australis, the following extract is taken from an IPCC fact sheet on the preparation of reports. It makes it quite clear that authors are not restricted to peer-reviewed literature.
“The authors will work on the basis of peer reviewed and internationally available literature, including manuscripts that can be made available for IPCC review and selected non-peer reviewed literature. Source, quality and validity of non-peer reviewed literature, such as private sector information need to be critically assessed by the authors and copies will have to be made available to reviewers who request them. Disparate views for which there is significant scientific or technical support should be clearly identified in IPCC reports, together with relevant arguments. Expert meetings and workshops may be used to support the preparation of a report.”
I can’t see anything in the IPCC section discussing economic and insurance losses which contravenes these guidelines. Can you?
No, you seem to be right. This guideline allows all IPCC authors to use any material from any source they have “assessed” – ie there are no prescribed standards at all.
This leads to the organisation having no accountability, and the author being personally responsible, for the choice of the incorrect Muir-Woods material.
Australis, you’re hard to please. First you say that the paper not being peer reviewed might not matter, then you affirm that its not being peer reviewed means that the organisation has no accountability.
You continue to insist that Muir-Woods paper was clearly wrong. The paper was published in 2008 (after the IPCC report was prepared) and from what I can make out from the condensed summary the writers had decided that the normalising relative to per capita wealth in the US meant that they had insufficient evidence to claim a statistical relationship between global temperature increase and normalised catastrophe losses. Whether that was a retraction from their original paper or not I don’t know, and haven’t the time or energy to pursue.
But in any case the IPCC statement quoted in my post seems to me to be open to this possibility when it says of the original paper: “The significance of the upward trend is influenced by the losses in the USA and the Caribbean in 2004 and 2005 and is arguably biased by the relative wealth of the USA, particularly relative to India.”
I see nothing here to suggest any grievous error in this section of the IPCC report.
Bryan – I thought the lack of peer review did matter, and should have taken the M-W paper out of consideration. I was surprised (and a little shocked) when you pointed out that there are no prescribed standards for any of the documents relied upon by IPCC authors.
I think I agree with your interpretation. The level of insurance losses is the best available measure of “extreme weather events” because they are fully documented and quantified and expressed in comparable (monetary) terms. But if relativity is to be measured over time or space, some statistical adjustments are almost inevitably required. In this case, after adjustments, there was no story.
But the IPCC author thought there was a story, and used the unpublished paper to make a point – presumably one that coincided with his/her worldview.
Australis, I don’t think you can infer that there are no prescribed standards for the documents cited by the IPCC authors. This sentence hardly invites them to choose whatever they want: “Source, quality and validity of non-peer reviewed literature, such as private sector information need to be critically assessed by the authors and copies will have to be made available to reviewers who request them.”
Your assumption that the Muir-Woods paper was chosen because the authors thought there was a story and used the paper because it coincided with their worldview doesn’t show much respect for the authors. If you want to know who they were for this chapter of the report you can see them here on the opening page – all ten of them from nine different countries, with three review editors from three more countries. My understanding is that the Muir-Woods paper was cited because it was the only one that looked at the global catalogue of catastrophes. The Pielke papers cited which normalised losses were for the US only. It seems to me quite reasonable that the authors should include the paper’s findings for this reason, and as I’ve already pointed out they hardly embraced it enthusiastically as proving a point they had decided beforehand they wanted to make.