An automatic weather station being installed on Butler Island, Antarctica
The belief that man is warming the Earth’s climate via greenhouse gas emissions is supported by evidence showing a modest increase in global temperatures over recent decades. But what is the scale of these increases, and are they in any way abnormal? To find out, we need an accurate record over a long period. This is where the University of East Anglia’s Climatic Research Unit (CRU) comes in, and why the “climategate” scandal over its leaked emails matters so much.
The CRU is one of the world’s leading climatic research bodies. Its scientists, along with the Met Office’s Hadley Centre, build and maintain the world’s temperature record. This may sound easy, especially as the figures they produce always seem precise: in 2007 the Intergovernmental Panel on Climate Change put warming over the past 100 years at exactly 0.74°C. But tracking such tiny temperature changes is tricky—even over the last century when we have had decent thermometer coverage. Do you measure highs, lows or averages? Should readings come from Siberia, Antarctica or Australia—and, if all of them, how do you weight the results for a global average? By land area? What about seas?
To get round this the CRU divides the world into geographical grids. It gathers data from meteorological offices all over the world, makes adjustments and obtains a temperature for each grid. Researchers then compare this result against a baseline of historical temperatures for that grid. The average of the differences across every grid reveals how much global temperatures today differ from historical temperatures.
But there are problems, even if you do this carefully. The first is urbanisation. Ideally, thermometers would be in the same place for long periods and unaffected by people. Yet they are often placed near airports, for example, where they are susceptible to an “urban heat island” (UHI) effect, as traffic increases or runways expand. This UHI effect has happened most in places where the record should be most trustworthy, like Britain and the US, where economic development has been strongest, so the surface temperature record has a manmade upward bias which needs to be adjusted for. The CRU’s adjustment methodology is not disclosed.
Even in the countryside, a thermometer on a farm could be exposed to more machinery today than a century ago. Comparisons of rural and urban thermometers have shown heat island effects of a few degrees celsius. Some studies claim that apparently rising temperatures are correlated with local economic activity rather than global warming. Other problems come when a thermometer is replaced, creating discontinuous data, so the series needs blending. This blending and averaging is far from perfect in places like Britain. But in Siberia and China the CRU has to take data without even observing the weather stations. (For 30 years there has been satellite data too, but this measures only at higher altitudes and has shown less warming than at ground level.)
This is why “sceptics” have, not unreasonably, asked to see the raw data. A scientist cannot say “I have discovered X” if he refuses to share the data to test his discovery. A 2005 email from CRU director Phil Jones to Australian sceptic Warwick Hughes highlighted this: “We have 25 or so years invested in the work. Why should I make the data available to you, when your aim is to try and find something wrong with it?” In another email he wrote that he had deleted “loads of emails” after receiving freedom of information requests, and had asked other scientists to do the same.
The good news is that now, post-climategate, the CRU and the Met Office have released data they had claimed was protected by copyright, or subject to confidentiality agreements. So the scandal has encouraged greater openness. But it has done less to solve a second problem, which arises when you try to deduce temperatures going back thousands of years. Palaeoclimatology (climate study of the history of the Earth) is harder than short term measurements, as there are no records. Temperature changes must be inferred through tree rings or ice cores. Yet some tree cores, for instance, suggest different histories from one side of the tree to the other, while their growth is changed by rainfall and CO2 as well as temperature. Another problem comes with the infamous “hockey stick” graph, devised by US climatologist Michael Mann and featured prominently in Al Gore’s film An Inconvenient Truth. This used tree ring data from Russia and the US to show temperatures gently falling for most of the last 1,000 years, then shooting up from the middle of the 20th century, like the end of a hockey stick. Yet the graph seemed to miss two crucial periods: the “medieval warm period” from the turn of the last millennium to the 15th century, and the “little ice age” at the start of the 17th century, when the Thames regularly froze. Mann claimed these periods were local in nature; sceptics, meanwhile, suspected that the techniques used to create graphs like the hockey stick had been designed to favour the idea that warming in the second half of the 20th century was unprecedented.
There is no conspiracy here. But the scientists involved in climate research for the past 30 years may have enjoyed their golden age too much. Research grants have flowed freely, although not, of course, as freely to scientists with contrary views. I am far from being a climate change denier. It seems perfectly likely that we are having, or will have, an effect on warming through the higher concentrations of greenhouse gases. But the evidence is not yet clear; there were, for example, periods of warming in the 19th century almost identical to the modest warming we seem to have experienced since 1975. We cannot rely on highly imperfect climate models as a basis for policy initiatives that cost billions and change how we live. An accurate and unbiased temperature record is critical.
Read what James Lovelock, Bjorn Lomborg, Ed Miliband and many other experts have to say about climate change in Prospect’s Copenhagen special
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Comments (116):
It’s an interesting specific subject, the Hockey Stick, others have seen it as you do, critical supporting evidence, including the ultra-warmists, you will have read the defences of it on realclimate for example, they would die in the trenches for it. But then they’ll die in the trenches for a lot of stuff.
I’m being diplomatic, yes, my real bug-bear is uncertainty-denial as a whole rather than this one example of it. There is a pov that if you take the right uncertainty bands all the way through from paleo to impacts and then policy costs and benefits you are left with faith and the precautionary principle.
Environmentalism generally is full of it, faith and uncertainty-denial. Monbiot wrote a blast on UK policy on solar pv (of which he is a supporter, in the right place) and some of the comments said ‘George, you mustn’t say these things, it gives comfort to the enemy, and it’s the right thing to do regardless of cost’ and regardless of truth and alternatives too, presumably.
‘We must do something’ and ‘it’s the right thing to do anyway’ and ‘we can’t go on like this’ and ‘oil will run out anyway so let’s do it now’ just confuse the conversation on impacts and policy response. It’s why I’m a Pielke-ist or Lomborg-ite or SonjaBC-ite by instinct, I don’t trust, in a rational sceptic way, the magical thinking of mitigation policy, I want to know what it will achieve, measured, and why it’s being proposed if it has no impact.
And I like the detail. As an example the stats used in forecasting wind intermittency seem to me very weak. Ireland is the only country that publishes 15 minute interval data on wind output, and the intermittency requirement is way beyond what the simplistic models assumed.
Yeah…pretty much on the same page as me I think. Kinda Lukewarmer but veering Tepidwarmer as more and more science breaks out. Ironic that the vast investment in investigation is turning up some very odd things…we are getting to understand strato water vapour alot more (which does not seem to help the AGW cause I’m afraid) and ENSO understanding has gone up big time.
Unfortunately the politics of both sides has made the poor honest science unspeakable – both sides have a lot invested.
From my own pov the ‘windpower’ stuff scares me as its an engineering nightmare to couple up the ebbs & flows pan europe. At the moment europe copes by letting the excess slosh over the euro-net, but if more and more windpower comes on song, its going to get more difficult to manage. I just do not understand how people can ignore the obvious limitations of this policy (unless it is of course just the stalking horse to get nuclear up and running, ha!).
I’m a bit of an outdoor person and enjoy wind driven sports…have spent years sitting on beaches waiting for the wind. I know it rarely blows in winter or summer (we windsurfers live for Spring/Autumn). During the recent cold snap just check out what percentage of power wind supplied compared to what its installed potential was…….scary bad return.
Ah well. I’ll leave you in peace. It was a good balanced blog. Be interesting to revisit this in a year and see what the comments look like then perhaps.
Roddy, though I remain unhappy with your original article I must give you credit for your even-tempered responsiveness on this comments thread. I just want to draw your attention to two news items: one concerning the IoP submission to Parliament and another adding one more frightening piece to the jigsaw of catastrophic environmental change: the kind of change we cannot risk, regardless of uncertainties concerning its exact shape and ramifications.
First, there is evidence that the IoP submission was, in a sense, hacked in its turn by an energy consultant (conflict of interest!) and noted denialist:
http://www.guardian.co.uk/environment/2010/mar/05/climate-emails-institute-of-physics-submission
Second, the feedback loops seem to be behaving just as the ‘warmists’ have warned. God help us if this accelerates:
http://climateprogress.org/2010/03/04/science-nsf-tundra-permafrost-methane-east-siberian-arctic-shelf-venting/
The focus of your argument seems to be that ‘AGW’ scientists refuse to acknowledge uncertainty in climate modelling. This may be true (those it is in response to a massive campaign of misinformation which exploits any hint of uncertainty in that science) but the essential point, and sorry to hector but it is a moral one, is that we already know enough, and the picture is clear enough, for us to devote our efforts to averting catastrophe. Hardly any climatologists doubt the soundness of the basic scientific conclusion that we are dangerously destabilising the biosphere.
http://4.bp.blogspot.com/_ACyqhI8FTfI/S0n-A2EVSMI/AAAAAAAAANY/cNFd6NHsYOo/s1600-h/phpThumb_generated_thumbnail.jpeg
And whereas it may not be your intention to distract the world from this danger, that is the policy of Big Carbon, especially in the States. Doubtless we’re coming at this from different angles, you as a maths man and policy wonk, me as an activist. But while reasoning and debate are always needed, now is also the time for action. Because if we wait for absolute certainty of catastrophe, it will be (if it isn’t already) too late to avert it.
geek time – there’s one bit of tech which will help re intermittency in my mind, i mean short-term 15/30 minute lapses in wind, not your spring/summer observation.
I may not get this quite right, but it’s a bit of kit which you have built into your freezer, say. It detects a slight fall in voltage (?) from the mains, indicating demand>supply, and with a random number generating thingy turns itself down, or off, for several minutes, ie using less power. After the random number of minutes it comes back on so your fish fingers don’t get soggy.
If you have enough of these around, with them all coming back on at different times, it can help local intermittency which otherwise will require oil/gas local generation of a temporary power solution type.
That’s the idea anyway.
i like your idea of revisiting in a year.
some of the more warmist blogs are ad homming like mad against the IoP. they really are crazy types. NO criticism is allowed AT ALL.
You’ll enjoy this post today by a very funny Czech scientist http://motls.blogspot.com/2010/03/met-office-claims-to-have-found-agw.html?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+LuboMotlsReferenceFrame+%28Lubos+Motl%27s+reference+frame%29
Gregory, thanks for the even-tempered compliment. It is terribly easy to end up name-calling, ad hom, side-taking – I’ve said enough on this thread about the disfunctionality of the debate, so thank you for engaging too.
Your post – The Guardian – am I being unfair when I think that the IoP submission shocked the warmists, and so it seems to me that Adam was trying to smear it? To me he hasn’t succeeded (Gill certainly seems a sceptic maverick, we don’t know what influence he had on the statement), in fact Adam got this quote from the IoP in his piece “The institute supplied a statement from an anonymous member of its science board (RC – note, not the energy lot), which said: “The institute should feel relaxed about the process by which it generated what is, anyway, a statement of the obvious.”" whbich is a pretty strong defence? I think that if the IoP make a controversial statement to Parliament on the hottest potato in town and stand by it we should consider that there may be some reason to the points they make, they should be considered on their merits, especially when they stood by them in the clarification and the quote above?
the Chemists said this: ‘It may also be necessary to incorporate an independent auditing system into peer review with the ability to demand access to raw data sets to ensure best practices are being adhered to.’, which, in the context of a climategate submission, is not to be ignored either. They also flirted with the IoP pov when they said ‘A lack of willingness to disseminate scientific information may infer that the scientific results or methods used are not robust enough to face scrutiny, even if this conjecture is not well-founded.’ (Is an inference equivalent to a conjecture? A question for language pedants there, I would have thought an inference classier than a conjecture!)
I went off-piste from the article in moving onto impacts and response, we differ in that you are a ‘catastrophist’ and I’m not, and I’ve described my Pielke-ist (a warmist) stance on ‘magical thinking’ re mitigation, and the need for an overly-sober approach to hints of alarmism in the impact area.
I haven’t seen the fingerprint of big carbon in my meanderings around scepticism and climate, I see mainly some weird anoraks like McIntyre, Watts, Id, EM Smith, Bishop Hill tilting at the establishment. Like any whistle-blowers, they are a bit odd, not perfect, which is roughly part of the defence of Jones et al in climategate – they’re only human. As you’ve seen, I aim off when it comes to the SPPIs of this world.
massive campaign of misinformation – this is a bit of a gavin schmidt meme, from where I sit the warmist establishment have had a pretty vice-like grip for the last decade or two on media and information and presentation. The blogs have appeared in the last very few years, but I agree since climategate it’s all gone a bit nuts.
I find it interesting how Pearce wrote all those pieces, and is, I understand, pretty furious at the claims of Schmidt on realclimate about his shoddy journalism. He had to report climategate, and reported it, very thoroughly. What his personal views/beliefs are we don’t know, but as a ‘warmist’ journalist admired by the AGW community again we should consider whether he had a point(s) when he criticises.
Thanks for the methane Arctic link – I read the http://www.nsf.gov/news/news_summ.jsp?cntn_id=116532&org=NSF&from=news press release. I got confused about whether it’s all warming caused? If it is, should the same thing not have happened during the MWA (the A is a nod to Mann!)?
You say you’re an activist – in what specialisation, as it were?
All the best.
The cost of averting catastrophic climate change are not enormous. They are such that it will delay the world´s expected economic growth by six months by the year 2050. That is to say it will take until July 2050 to reach the level of wealth we expected in January 2050. The strategies needed to reduce the world´s dependency are worth puruing even absent the appalling risks of climate change. Who wants to continue sending money to corrupt middle eastern countries and to Russia? Who wants to continue the destruction required to extract tar sands?
I´m pretty disappointed Prospect thinks a fund manager is even a worthwhile commentator on this subject. Actually I am close to apopleptic. This debate is too important to leave to the likes of the kind of people who have most to gain from doing nothing to avert a calamity with appalling social and humanitarian consequences. Would you ask tobacco industry representatives to debate the link between smoking and cancer?
Right, so have to admit that this is the first time that I have bought “Prospect” as normally a “The Economist” kindda gal but got lured into buying the magazine by the tantalising heading “Why feminism favours men” (thought it was to do with double workload but app all about splitting the bill and having innovative sex!) and went to website with the intent of posting a comment to Jim Pollard’s rather funny piece, which actually got a valid (albeit annoying) point but frankly lost the will to live somewhere between trying to summarise the position on parental leave (well, according to Scandinavian studies it doesn’t really work unless you earmark it) and Laurie Penny asserting that women enjoy sex too (eh, yes and some of us enjoy a sense of humour as well) so decided to give up on the feminist movement, probably not much fun these days any way as any bra burning is clearly out of the question (just think about the emissions caused by a good under wiring and we would probably totally spoil “the Hockey stick” graph so would have to fold the offending item neatly together and place it in an orange recycle bag to be collected on Fridays, which just isn’t quite the same). So gate crashing the “climate change party” instead although since no recent postings the “guests” might already have left the party? Any way seems to me that asking to see the raw data is pretty much what we in my line of work call asking for “further and better particulars” which makes a lot of sense as all parties then have the opportunity to form an informed opinion before arguing their case instead of people just ranting away and introducing new evidence when it suits them. Saves everybody a lot of time and ultimately produces a much better result (as in “just and fair”). The climate change believers clearly got a case to argue (we are probably discussing extent of damage and appropriate remedies on this one) so others input should be welcomed rather than resented.
Bjørn Lomborg is currently filming his movie “Cool it” (app Al Gore has declined an offer to participate (!) but Rajendra Pachauri and Bill Gates might take part) due out in September so would be nice if meant that more balanced view but probably just further polarisation. Read that Lomborg recently returned mightily depressed from a visit to UK as apparently the children here draws pictures of the Earth consisting entirely of blue water with a couple of dead polar bears and penguins thrown in for good measure Rather depressing to grow up thinking that you will shortly be standing on the last piece of ice holding your teddy! Btw to be fair Lomborg has been financed to the tune of at least 10 million pounds (from 2002 until 2012) by the Danish gov although they probably rather regret that now.
Kind regards,
Early morning bird
Ps re tobacco industry comment. Yes, I know it is a classic ref but not sure what relevance author’s day job have unless you are suggesting that he is “going long” on the Earth surviving?
Richard:
“This debate is too important to leave to the likes of the kind of people who have most to gain from doing nothing….”
hmmm. I am a 50 year old father of four, I’m not sure on what basis I have most to gain? I have a house, a job, a family, I benefit in general from the City existing, because it is where I am employed, I’m a cog in the capitalist system; I think an out of work Corus steel-worker might have more to gain given that he has been sacked because of carbon credits, or a Spaniard crowded out of employment by expensive renewable energy (see the Juan Carlos University paper).
I don’t think the debate should be ‘left to’ any particular set of people, it’s too important for that, and am not sure why the article I wrote would be any more or less relevant or true or false had it been written by a bus-driver. It would likely have been less so if written by Greenpeace. The bus driver and I both have notional independence.
Your post is a generalised form of the ad hom approach which I have criticised above – no mention of the issues (other than to blur them) or of what I wrote, just a general casting of nasturtiums as to my motives and bias.
On your specific points, although they were not connected to my article, I think my financial training might make me reasonably competent to comment on Stern, as in your ‘The cost of averting catastrophic climate change are not enormous.’, and a degree in economics and politics specialising in international relations would enable me to at least join in the ‘Who wants to continue sending money to corrupt middle eastern countries and to Russia?’ conversation (I do, otherwise there won’t be any food in Tesco).
I remind you my article was only about the reliability and uncertainty of historic temperature records and paleo reconstructions, and hence the reliability of current detection and attribution, not about policy response or global morality.
Do tell, who is allowed to think about and debate this large subject?
early morning bird – laughed all the way through. Given my fund manager job I am naturally biased about women enjoying sex, because being richer than most and shockingly bad in bed I prefer it if they want my money, it’s the only way I can keep them. So my views on the female orgasm are not worth hearing, and you should be apoplectic should they ever appear in Prospect.
x
Glad you liked my comment as almost made me late for court so had to do a “Usain Bolt” all the way up Kingsway which frankly isn’t easy wearing heels and carrying 5 bundles.
Ah yes, the good old “demand-supply” theory still holds. So no worries should you ever divorce. Went to fancy smancy gallery dodah yesterday evening and after that for a drink around Chelsea with a friend and I am happy to report that both places would have made Adam Smith do the roly-poly out of the sheer joy of seeing his theory put to good use. Think men have (as a general rule) been smarter on this one though, as have in the past (in vain) tried to explain to girlfriends that if one person got youth and looks and the other person got money and job then frankly some of those assets will be more exchangeable than others (not to mention the rate of deterioration! surely I am not the only woman who finds that after turning 35 ones bum becomes a bit of a Sisyphus job???)
On the bright side if you have managed to impregnate a woman (women) 4 times then I reckon that you almost certainly got the basics right but should you ever want to broaden your repertoire (not that you probably need it, please see above) then there was a fab documentary on BBC4 Monday on the trail-blazing feminists who discovered the clitoris in the 70’s. Extraordinary archive footage – Germaine Greer was even scarier in her youth.
Right, back to work. I have a terrible feeling that I am suppose to exchange something with somebody, sometime, today. I will, if I got time, try to find the will to comment on that other opinion.
Have a nice day.
Early morning bird
Just to let you know that your comment from yesterday made me laugh so much that I actually read most of your blog (belated congratulations on your birthday). Well, you may be shockingly bad in bed (I will take your word for it!)but you certainly got a sense of humour. x
you seem to have a tongue on you too. Alarmed by your liking for The Economist, how could you, and also the Sisypheian comment. Send me a mail at roddycampbell at gmail dot com, as otherwise this thread is drifting dangerously OT.
Oh, and read Matt Ridley’s review of The Hockey Stick Illusion, on the Prospect website. VG. Complements my piece re detection.
Dear Mr. Campbell,
I must confess that your suggestion that we go “off blog” left me reeling as I have frankly always assumed that the only reason men would want my opinion on anything is because of my looks.
Started reading the book and will email you my initial comments shortly.
To any budding sceptic, I highly recommend Peter Taylor’s book “Chill” (available from Amazon or your library), which is a scientific look at AGW, most especially at what has NOT been factored in. Written so that the layman can easily digest it, it is a comprehensive rebuttal of what the cooling denialists claim.
Jeremy Poynton said:
“To any budding sceptic, I highly recommend Peter Taylor’s book “Chill” (available from Amazon or your library), which is a scientific look at AGW, most especially at what has NOT been factored in.”
Jeremy, why is it that Taylor’s book didn’t go through peer review as all normal scientific hypotheses do? why is it that Taylor quotes the completely discredited pseudo scientist Lord Monckton? And why does Taylor not want to advertise the biography he wrote, called Shiva’s Rainbow where he thinks that plutonium is a mystical homeopathic substance and admits to communication with a discarnate guru?
John,
I shall most def get Shiva’s rainbow. It sounds most interesting and delightful. Was actually planning to read “The rational optimist” by Matt Ridley next. Anybody read it?