My attention has been drawn to a blog piece by Andrew Bolt which purports to show graphical evidence to support the central dogma of the Stupid Cult of Cooling.
The centrepiece of Bolt’s article is a monthly series graph of global average temperatures from the Hadley Centre for Climate Change. On the basis of this graph Bolt claims that:
As you see, since 1998—an unusually warm year thanks to the “El Nino” pool of warmer water in the Pacific—the world’s temperature dropped back to a steady plateau, followed by a few years of cooling.
What Bolt either does not understand, or is not telling his readers, is that monthly series graphs register very short-term (i.e. monthly) fluctuations in global average temperatures. Short-term fluctuations tell us little about long-term trends, which is what the global warming debate is about. I explained this in the LP post linked to above, with reference to year to year trends which are subject to the influence of short-run trends such as movements in the El Nino/La Nina cycle (hereafter referred to as ENSO). What is true with respect to yearly fluctuations holds a fortiori for monthly fluctuations.
Nonetheless the Hadley Centre’s monthly series graph has provided the Cooling Cultists with their talking point du jour. As can be seen, Bolt has drawn particular attention to the fact that the monthly figure for January 2008 is almost 0.6 degrees C lower than the figure for January 2007. What’s wrong with this? Quite simply, a graph such as the Hadley monthly series graph will, due to very short-term climate fluctuations, exhibit a high degree of volatility around a long-term trend line, and so it is not very difficult to find two points from the same month in successive years which seem, to the numatistically challenged, to indicate a significant trend. In the case of the Hadley monthly series data, if one picks the month of March rather than January as the basis for comparison, one finds that there is no “cooling” whatsoever – indeed, March 2008 was marginally “warmer” than March 2007. But in either case this is cherry-picking, not rigorous quantitative analysis.
“March 2008?” I hear you ask. “But the graph stops at January 2008. How can you know what was happening in March 2008?”
Quite simply, dear reader, the Hadley Centre’s monthly series data, and graphical representations thereof, for the period from 1850 to June 2008, are in the public domain. But if you study them carefully, you find that they don’t end in the same striking downward spike as the graph which ends in January 2008, and would therefore not tend to support Andrew Bolt’s polemical point. Not that I accuse Mr. Bolt of withholding this information from his loyal readership of Cooling Cultists. He may simply not have got around to looking up this information – in which case, however, questions arise as to whether he has discharged his due diligence in researching a topic on which he writes so profusely.
[Update: In response to Kingsley at #7, the monthly series data referred to in the previous paragraph is not depicted on a graph at the Hadley Centre site, but is available here as a data set.]
However, as already stated, the monthly average series is not what one should rely on to attempt to discern a long-term warming, cooling or stationary trend. What we can rely on for this purpose are things called smoothed time series data, as shown in the plot of annual series smoothed with a 21-point binomial filter for the period 1850-2007.
But wait, there’s more (which is also either not known to Andrew Bolt or not reported to his readers). The Hadley Centre states that:
We have recently changed the way that the smoothed time series of data were calculated. Data for 2008 were being used in the smoothing process as if they represented an accurate estimate of the year as a whole. This is not the case and owing to the unusually cool global average temperature in January 2008, it looked as though smoothed global average temperatures had dropped markedly in recent years, which is misleading.
The Hadley Centre elaborates on why this is misleading here. The article also discusses the role of the ENSO cycle in affecting global average temperatures. Clearly, a more accurate picture of underlying long-run trends of warming (or otherwise) can be achieved by correction for ENSO fluctuations using linear regression techniques. The fine souls at RealClimate have just done that and found that this confirms the existence of a warming trend both in the long term and in the past decade:
This last decade is still the warmest decade in the record, and the top 8 or 10 years (depending on the data source) are all in the last 10 years!
The ENSO-corrected annual series also show that, even if one adopts the Bolt methodology of trying to deduce warming or cooling trends from individual years, it is not tenable to claim that global warming “stopped in 1998″ as the warmest (ENSO-corrected) year on record is either 2001 or 2005, depending on whether you use the Hadley or GISS data.
A similar exercise in ENSO-correction has been performed by Robert Fawcett of Australia’s National Climate Centre, using smoothed time-series data. He concludes that:
Ultimately, the correctness or otherwise of the cooling assertion is something for which the observations will in time provide the answer. On balance however, the observational evidence of the past decade is against it.
And a further finding in relation to the Stupid Cult of Cooling is published in a document which Andrew Bolt presumably knows about:
The dissent took a curious turn in Australia in 2008, with much prominence being given to assertions that a warming trend had ended over the last decade. This is a question that is amenable to statistical analysis and we asked econometricians with expertise in analysis of time series to examine it. Their response, that the temperatures recorded in most of the last decade lie above the confidence level produced by any model that does not allow for a warming
trend, is reported in Chapter 5 (Box 5.1).
The material which I have presented here is material which I have accessed and compiled in my own time from reputable online sources. It was not difficult to access or to understand and interpret. Andrew Bolt is paid top dollar by his various employers as a commentator and one would think he owes it to both his employers and his readers to exercise due diligence in researching the topics on which he chooses to comment and in giving due consideration to important, and readily accessible, information which bears on those topics.
Indeed Bolt does know that paragraph. My comment is the third one down, under the name of “The Dude”.
Sure, he’s just one guy, but his existence and profile pretty well gives the lie to MSM claims that they do ‘fact’ better than bloggers or anyone else.
His recent performance on The Insiders was a disgrace, his bullying tone and demeanor regarding his false claims were insulting to the other guests, both of whom clearly had a solid understanding of the issue.
When will the ABC fulfill it’s obligation to inform the public properly by striking him off the booking list? Of course we know that if it does he’ll cry censorship and wear it like a badge, still, that’s a small price to pay in the pursuit of a proper public education on AGW.
Paul, thanks for this. Very timely.
This point from your earlier post is very important and worth emphasising:
A couple of further items of interest.
David Karoly pointed out recently that that 2007 was the warmest La Nina year ever.
NASA GISS saw 2007 this way:
Finally, these graphs show the remarkable relationship between GHGs, temperature, sea levels and ice sheets over the past 450,000 years. There is a hidden factor driving these dramatic changes, the effect of periodic changes in the earth’s orbit, a relatively weak forcing, which becomes quite strong by virtue of the changes in the albedo effect on ice sheets, which has been a major factor since the establishment of the Northern Hemisphere ice sheets about 3 million years ago. However the paleoclimate record shows that GHG forcings move the system very powerfully over a period of time, again by triggering feedbacks in the system.
In the light of the above a few months, a few years, or even 10 years or more of superficially aberrant temperatures, but for which there are in any case plausible explanations, are neither here nor there.
Rudd, as alleged by Bolt, is not panicking. It is more accurate to say that he’s almost doing nothing. And there is plenty to worry about still.
Shot version: Bolt is wrong, yet again.
Ok, I think we all got that one.
Phil (et al), how many people watch ‘The Insiders’? 9 am Sunday morning on the ABC, hmmm, let me guess, no one? I prefer Bolt being bought off a little bit so he doesn’t go ranting about ABC bias even more than he does.
wilful, the way these things work, “Insiders” tends to set the press gallery agenda and that of the political class. It’s not intended to be for a mass audience – as the name indicates! The questions really should be:
(a) should the ABC frame the show as a whole in the way it does?
(b) aren’t there some sane conservatives to provide “balance”?
It’s a bit of an indictment on the quality of the conservative punditariat that the only ones they can find to appear on it are Bolta and Hendo.
I wouldn’t be using a “21-point binomial filter” in the court of public opinion!
And I would question removing the ENSO-signal to smooth the trend line. Work with the actual temperatures please, not a supposition or hypothesis.
The actual temperatures show a steady increase in temperature over the last century with several flat or cooling phases, one of which is the last ten years.
People are entitled to ask whether this ten years constitutes a long term trend.
I clicked on the link for the 1850 – 2008 numbers and all graphs appear to show till 2007 only or if they are showing 2008 they aren’t tagged that way and all appear to show a downward direction?
Craig, my main experience from following trends is in share market trends. If I were using trend lines, I’d draw a channel, and ignore single outliers like 1998. I’d also use several moving averages. In this case I think it’d be interesting to use a 5-year moving average and plot it over a 30-year moving average, extrapolated to bring it up to date.
The reason for the 30-year average is that this is the threshold climatologists often use to demarcate the difference between weather and climate.
When the 5-year average crossed down through the 30-year average, I’d start to get really interested. In the case of shares I’d be using different averages and check with other instruments.
Yes, and the answers are in the post and the links, and plenty of information that would have been available to any conscientious and open-minded journalist.
People could also be entitled to ask whether 157 years (1850-2007) is a long term trend, or a mere blip.
It’s easy to poke holes in the case for AGW. You can cherry pick areas which have cooled, and ice cover has increased. You can bring into question the motivations of the IPCC whose very existence depends on AGW’s existence. You can argue about the accuracy of the models. You can argue about the accuracy of measurements. You can believe the science or not.
For me the big argument is whether to use the precautionary principle in developing policy.
If you believe in AGW you will no doubt say yes.
If you believed that Saddam had WMD, you would have said yes, we’d better act, in that case too.
This precautionary principle can be very flaky. If you choose to use it, where do you set the threshold for action?
Phew! We don’t have to worry anymore, it’s all natural quotes one of the SMH’s resident AGW denialists.
http://blogs.smh.com.au/urbanjungle/2008/07/media_ignores_g.html#comments
He qualifies so how come he’s not on Insiders?
Craig, it’s unfortunate that the debate is usually conducted (at least in the popular media) in terms of either global warming either definitely will happen/is happening, or definitely won’t happen/isn’t happening. In terms of the scientific debate, it’s largely about probabilities. In terms of how lay citizens interpret the scientific debate, it’s about which body of scientific opinion is most likely to be nearer the mark in terms of its assessment of the probabilities. In terms of the policy debate (which is where the use of the precautionary principle comes in), it’s about what constitutes the most prudent course of action in the light of those probabilities.
As Professor Garnaut explained, the balance of scientific opinion is currently strongly on the side of the view that significant global warming arising from human activities, over and above anything that may be due to natural variation, is much more likely than not. It is therefore prudent to take action to minimise the perceived probability of harmful climate change, especially when that action will have other positive consequences such as creating a more energy-efficient Australian and world economy, reducing demand for finite fossil fuel resources, minimising other forms of pollution and environmental impacts associated wiht burning carbon and removing vegetation, etc.
The SMH seems to have taken a denialist line in recent times with great prominence giiven to both Miranda Devine and Duffy in Saturday’s edition with their usual concoctions of half truths, spin and outright lies.
It’s enough to make one cancel the subscription.
That and the fact that there’s rarely anything actually worth reading, certain book reviews excepted.
Craig, it’s not all that easy if you disallow cherry picking.
In geological time it’s a blip. But have a look at the PETM event 55mya when global temperatures rose by around 6 °C over 20,000 years and recovered over perhaps about 100,000 years. Now it looks like a mere blip.
James Zachos says that we are now forcing the climate about as much but 30 times faster.
A temperature rise of 0.8C and CO2 levels of 386ppm are not trivial if you look at the paleoclimate record and the implications for temperature and sea level rise.
The worry is the scale of what we are doing and the speed with which we are doing it. The economist Martin Weitzman thought here has been nothing like it in the last billion years. If you want to know what he though about risk and the precautionary principle you could do worse than start here. If you do be sure to check out Roger Jones’ comment.
There’s plenty to worry about.
“If you believe in AGW you will no doubt say yes.
If you believed that Saddam had WMD, you would have said yes, we’d better act, in that case too. ”
Apples with oranges I’m afraid. There is a fair body of work on AGW. There was no verifiable information available in the public domain with regard to the existence of WMD. The existence of WMD was an assertion, you took it on faith. AGW is a debate with information based on observation available to both sides.
I like watching Bolt on Insiders. When Annabelle Crabb described his defence of climate denialism as ‘heroic’ the other week i laughed so hard I almost spilled my coffee. I don’t get a chance to see him anywhere else, so am happy to have him trundle out every other week to hate on George Megalogenis. I really want the Libs to back away from the ETS so that next year when the US changes their position they can look like the spineless lapdogs they really are.
I would miss Bolt if he were to disappear from Insiders. The zoo would be very dull if it only had tigers and owls and no marmosets.
Actually kymbos you have an interesting point. Since Australia’s ultimate role in reducing atmospheric carbon is largely symbolic, I think for the sake of the actual problem we’re trying to fix here, we could let the Libs take us on a walk down a dead end, then they could be left there for a long time to come. Possibly benefiting us all greatly.
However I optimistically believe that a good, responsible opposition is a benefit to a democracy, and would prefer the Libs to work with the government to improve it, rather than against it to ruin it (and themselves at the same time). But it is tempting.
Kingsley at #7: I’ve updated the post to take account of your concern.
Patrick B, I would argue that believing in AGW is an article of faith too.
Climate modeling is too advanced for most to understand. There are so many things which could affect climate, and the Earth’s weather systems seem impossibly complex. If one chooses to believe in AGW, you accept on faith the weight of scientific opinion. This may be prudent to do. But scientific opinion is not fact, it’s a hypothesis. Unfortunately in regards to AGW, it’s problematic to wait for the proof that science is right. But until then I say it’s faith.
“Andrew Bolt is paid top dollar by his various employers as a commentator … ”
I think this is a misinterpretation of his role. He’s just there to collect eyeballs to look at the advertising and hence increase revenue. I’m sure he knows it. That doesn’t make him any less despicable, but it’s time to stop treating him seriously.
The scientific method does not provide “proof” that the science is right, except in a trivial sense. Science consists of hypotheses which attempt to explain observed (or observable) data and which are (at least in principle) falsifiable. The above sentence therefore should read “Unfortunately in regards to AGW, it’s problematic to wait for the hypothesis to be falsified.” This is because the hypothesis could only be decisively falsified if we were to actually double the concentrations of atmospheric GHGs and find, several decades later, that the climate system had not behaved as predicted by the hypothesis. I don’t know if anyone actually advocates deliberately doing this for the purpose of advancing our knowledge of the climate system.
paul thanks for that,but I don’t know if I am suffering a case of temporary dyslexia but I can’t see the 2008 numbers. Have they just simply not titled the axes correctly? That said I clicked on the links about suggesting relying on this recent cooling is misleading due to Nina bringing up cool waters from the ocean depths. If this is the case I would presume there have been other periods where it can be demonstrated the temporary cooling was caused by this?
Kingsley, the article which discussed La Nina mentions that 1999 was a year in which La Nina exercised a cooling effect, and compares 1999 with 2007. To reiterate, the 2008 numbers aren’t on any graph but are in the data set I linked to in the update.
Kingsley, from Paul’s earlier post there’s a link to an article by David Karoly that identifies cooling from some of the earlier La Niña events.
There are other things that will do it also, like a decent volcanic explosion for a couple of years.
The one I worry about is the statement by Kenneth Caldeira who reckons that coal-fired power stations have a net cooling effect for their first 7 years. This is because the aerosols they give off have a short life in the atmosphere, but the residual airborne fraction of CO2 persists for a very long time.
In the light of what India and China are doing in recent times this could spell trouble before too long.
Rather than shadow-boxing over alleged inadequacies of all current probablistic arguments asserting AGW, I’d like AGW sceptics to state unambiguously their minimum requirements for a pro-AWG argument that would satisfy them.
And then perhaps AGW sceptics could argue among themselves over their differing standards of persuasiveness.
Without that benchmark it is simple for AGW sceptics to continue to raise the bar on acceptable levels of persuasiveness.
Come off it katz, they’re not going to play that game.
I’ll readily pony up money (say $500) in a wager with a denialist that the earth will be warmer in five years (averaged and all that). Should be easy money for a denialist. Terms and conditions to be worked out here by mutual consent and public scrutiny and input.
AGW sceptics should not remain silent in light of Wilful’s questioning of their bona fides.
AGW sceptics! Please prove Wilful wrong by stating your minimal standard of persuasiveness, as outlined by me, #25 above.
I’ll add my $500 to wilful’s $500 stake. AGW sceptics – that’s one thousand dollars that could be yours if you take wilful’s bet. I repeat – ONE THOUSAND DOLLARS. ONE THOUSAND DOLLARS!!! Hell, I’ll throw in a carton of Coopers to sweeten the deal. Whaddya waiting for?
Paul – Thanks for link. I’ll go away and digest. I’m a sceptic but I am interested to hear the other side’s arguments. We aren’t all cranks.
Make it 5 years from when the terms and conditions are ironed out – 3,000 comments hence.
Katz suggested: “Without that benchmark it is simple for AGW sceptics to continue to raise the bar on acceptable levels of persuasiveness.”
Good point. But we may be waiting a while. They may just say they refuse to nominate a level of persuasiveness until CHINA and INDIA and ANDREW BOLT have done so. And a 2/3 majority in the General Assembly + the Vatican and the General Synod.
Good luck with the bets.
Katz – in the meantime you could lead by example and say what you would need to observe to decide AGW is not happening.
It is like a weird sci-fi movie “The Graphs” Cue scary music….
Generally you can look at a graph of the stock market or my bank balance and decide on the state of them (both bad)
But world temperature graphs,no way. You need to do 11 year averages, OLS (whatever that is) take a 30 year trend, squint your eyes and then…get any answer you want.
With due respect, chrisl, that’s not the case. You have to have a reason for selecting particular averages.
Fair enough.
1. A persuasive argument that CO2 is not a significant greenhouse gas.
or
2. A persuasive argument that human activity since the beginning of the Industrial Revolution (c. 1750) is not responsible for a majority of the measured major increase in atmospheric CO2.
Now it’s your turn.
I imagine only the deliberately ignorant and desperate far right-wingers pay Bolt any credence or respect. He more and more is beginning to resemble Ackerman.
Bolt either thinks that most governments of the world have been suckered by false science or some global conspiracy and, that his two seconds of Googling are superior to the vast majority of scientists.
Obviously Bolt’s position is nothing to do with science and everything to do with right-wing politics.
I look forward to his calling forth those minority of doctors who believe smoking doesn’t cause lung cancer. Bolt would have had fun during those years denigrating the reports and analysis of the majority of scientists and doctors revealing the dangers of smoking.
[Dr Nelson faces a leadership test this week as he attempts to convince the partyroom to change the Coalition's climate change policy to abandon support for an emissions trading scheme unless there is strong action on emissions by big polluters such as China and India.
While the policy switch is not supported by many key players in shadow cabinet - including climate change spokesman Greg Hunt, Deputy Opposition Leader Julie Bishop and Treasury spokesman Malcolm Turnbull - it is strongly backed by the right-wing of the party. These include frontbenchers Nick Minchin, Tony Abbott, Eric Abetz and a significant group of backbenchers including Western Australia's Denis Jensen and NSW's Concetta Fiervanti-Wells.]
http://www.theaustralian.news.com.au/story/0,25197,24093309-601,00.html
It is instructive that those expert in the politics of hate, spite and the extreme right wing are also the driving force for a LNP party policy of climate change denial. They are standing their shaking their fist at the sky, living in denial and determined to let their ignorance push the LNP further into irrelevance – which this stance will do.
Cue Obama, Gore and others around next election time.
Newspoll has me beating Bolt 84 to 12.
Climate change wholly or partly caused by human activity – 96
Not caused by human activity – 3
Uncommitted – 3
Back a step Brian.
Is climate change occurring?
Yes – 84
No – 12
Uncommitted – 4
Labor – 91% yes
‘Coalition’ – 73% yes
Interesting age split too – 18-49 87%*, 50+ 78%
Tim Colebatch summarises a few other polls going round with climate change: http://www.theage.com.au/opinion/on-the-road-to-nowhere-20080728-3m85.html?page=-1
Of course Bolt believes it’s an Al Gore created conspiracy.
It’s the Vast Pagan Lefty Conspiracy to be precise, to drive us back to the caves and force us to knit our own clothes out of lentils or something.
Oh, and Greens = Hitler, according to Bolt. Truly repulsive.
I’m quite surprised by the level of AGW belief in Australia. Those numbers have to be some of, if not, the highest in the world. Bolt gets his hysterical columns published in the Herald Sun and the Courier Mail (combined readership of more than 500,000), and has his blog promoted all over news.com.au websites, as well as his regular appearances on the ABC and commercial TV. But few appear to be listening to him on the Vast Pagan Lefty Global Warming Conspiracy. Obviously, his audience is mostly laughing at him instead.
Katz _ I think a “persuasive argument” is too ambiguous I think it needs to be in terms of measurements. That the earth hasn’t heated up over such and such a period. I actually don’t know for sure what that number/timeframe should be to be perfectly honest but think an empirical test is better.
We know how many people watch Insiders – Courtesy of Crickey -
“News & CA: Nine News did strongly last night, winning Sydney, Melbourne and Adelaide. Seven news won Brisbane and Perth. Ten News averaged 820,000. SNS News, 193,000. In the morning — Weekend Sunrise with 437,000 viewers, Landline on the ABC at noon with 268,000; Inside Business on the ABC at 10am, 166,000, Insiders at 9am on the ABC, 163,000, Offsiders at 10.30pm, 151,000; Sunday from 7.30am for the penultimate program, 115,000; Meet The Press on Ten at 8am, 34,000.”
Bolt was demolished by a contributer to Crickey and then he appeared to defend himself on Crickey. What next? Several people resigned (or threatened to if he appeared again) their subscriptions. Bolt liked? Not so much.
Be that as it may, Kingsley, the world still awaits your counter-offer.
And for argument’s sake I would offer very generous terms to the time-series statistics adduced by AGW deniers. I would accept a lower level of confidence from AGW deniers than from proponents of AGW.
Your turn…
By the way I heard that the insiders on Insiders are paid $600.00 for their hour. More that I am paid in a week. And I can make stuff up just as easliy and as eloquently as any of them. My proof? See my contribution here on chemistry lessons last week.
And when it’s all done and dusted, there’s a thousand dollars sitting there saying that the world is getting measurably/statistically warmer, and will be so in only a couple of years.
wilful and others, if you want to increase the pot to tempt the delusionists a bit more, count me in for $500 too. (Easiest money I’ve ever made if Kingsley or some other accepts … )
Should make the wager over at tim blair’s site, except for all the dreck you’d have to wade through to get anywhere near a deal.
Darryl wrote: “I’m quite surprised by the level of AGW belief in Australia.”
I think the sea change in Australian attitudes occurred in the few months after the Al Gore movie was released. Not sure why, but.
Environmental awareness? vocal local scientists talking about it for years? publicity about the drought? water restrictions? [yes, I know the drought may not be a symtom of AGW].
Back (around 1989 I think) a similar sudden change occurred concerning recycling paper in big cities. The national debate about a proposed pulp mill in Tassie; concerns about possible toxic releases from a bleaching process there; the recognition that toilet paper (FFS) didn’t need to be made from bleached paper… Within a couple of months, waste paper recycling in Melbourne SHOT UP. (Schemes had been running at a low level for years…..). The APM plant at Fairfield couldn’t cope with the arrival of too many bales of waste paper for recycling.
Sudden awareness: immediate action by citizens. It can happen. I think it’s started already (in a small way) with CO2 emission reductions. Now the citizens look to their politicians to take further positive steps.
Quickest way to get a response: email Bolt and Blair, and CC a few journalists from Crikey (and elsewhere).
Just thought I’d mention that further to my comment at 3 about NASA GISS finding that 2005 was the warmest year and that 2007 and 1998 were equal second, http://bravenewclimate.com/2008/08/08/climate-change-qa-seminar-1-is-the-earth-warming-discussion-threat/#comment-14“>Christine raised this issue at Bravenewclimate recently.
[Don't know why that link looks like that - can't fix it!]
In response, Prof Barry Brook advised:
Of course Bolt gives James Hansen, one of the world’s most eminent climate scientists, a juvenile put-down:
First, Hansen wasn’t Gore’s GW adviser. Gore asked Hansen to cast his eye over his slide show, that’s all.
Second, most climate scientists thought Gore got the science pretty right.
Third, the reworking of data was a minor correction to the US record which nominally made 1934 the hottest year in the US rather then 1998. But the differences, both before and after were not statistically significant. Much ado about nothing!
Bolt also ‘overlooks’ the different baseline period of the four metrics, and so imagines conspiracies or manipulations, because they appear offset. Yet it is a simple enough procedure to standardise them, as has been done conveniently in one of the example “make-your-own-temperature-charts” here http://www.woodfortrees.org/plot/hadcrut3vgl/from:1979/offset:-0.15/plot/gistemp/from:1979/offset:-0.24/plot/uah/from:1979/plot/rss/from:1979 at Wood For Trees. Then most of the differences, especially in recent months, vanish. Indeed, the biggest discrepancy among the metrics in the 29 year shared record was… 1998.