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« An analysis of the energy crunch | Main | Looney green tunes »

Misconceptions and mislabellings

So, some minor brouhaha this morning over Roger Harrabin's piece about Richard Tol this morning. In it, Richard is quoted as follows:

Prof Richard Tol predicts the downsides of warming will outweigh the advantages with a global warming of 1.1C - which has nearly been reached already.

This is contrasted with Matt Ridley, quoted as follows:

Matt Ridley, the influential Conservative science writer, said he believed the world would probably benefit from a temperature rise of up to 2C.

And if you refer to the transcript, which Roger has helpfully made available at Joe Smith's Climate Creativity site (!) you can read this:

RH: I mean I’m intrigued on this because other contrarians are talking about, ‘Oh well, we’ll have benefits up to two Celsius.’ Matt Ridley, for instance, says, ‘Oh, anything up to two Celsius of warming, the earth will probably benefit.’ Do you disagree with that? [CB: Matt Ridley and Richard Tol are both advisors to the Global Warming Policy Foundation, a climate skeptic lobby group based in the UK]

RT: I think that’s a bit too optimistic, yes.

RH: But I think he references you in order to make that conclusion.

RT: All sorts of people put all sorts of things in my mouth. I would not hold it against Matt Ridley. I mean compared to what other people have put in my mouth, Matt is actually a good guy.

I get the impression that Richard has subsequently thought about this and has realised where this misunderstanding arises.



Take a look at the well-known Figure 1 from Richard's 2009 paper.

As you can see, Matt is talking about where the line crosses zero again, and Richard about the maximum. So no, there's not really a difference of opinion here at all. Indeed Richard has said that he misspoke...


This is a bit unfortunate for Roger, who has an article under his byline describing a difference of opinion between Matt and Richard that doesn't actually exist. You can see why he would have written what he did though.  It's a bit of a car crash really. A lot of correction of the record is going to be required.

But there's one other wrinkle here that bears looking at. Just read the first sentence of the caption [emphasis added].

Figure 1 shows 14 estimates of the global economic impact of climate change, expressed as the welfare-equivalent income gain or loss, as a function of the increase in global mean temperature relative to today.

So how does this equate to the "nearly reached" in Roger's article? Is the caption wrong? I'm confused.

[Update: In the comments, ATTP says that the figure caption has been amended in a correction to "relative to preindustrial"]

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Reader Comments (72)

"they should include the biology in their models, but he said they hadn't got the physics right yet"

The Biosphere contains two thirds of the carbon stock of the atmosphere biosphere system

Atmosphere 700 Gt 0.002% of total stock in ocean, atmosphere, biosphere and sediments
Biosphere 1,170 Gt 0.004% " " " " "

Carbon dioxide fluxes between the atmosphere and biosphere are an order of magnitude larger than the annual increment of CO2 to the atmosphere from fossil fuel combustion.

Biosphere to Atmosphere 60 Gt
Atmosphere to Biosphere 61.3 Gt
Fossil fuel to Atmosphere 6 Gt

If they are not including "biology" in their models then they are missing out on most of the action.

Nov 16, 2015 at 5:16 PM | Unregistered CommenterPaleoclimate Buff

harrabin has of course sought refuge in pointing to another squirrel..
retracting his errors are below his high overpaid paygrade.

Nov 16, 2015 at 5:44 PM | Unregistered CommenterVenusCold

For example, it is generally reckoned that malaria incidence would be 10% lower if climate were as it was 150 years ago (and everything else is as it is now)."

And just how is this "reckoned", Professor Tol?

Professor Reiter "reckons" otherwise: (

"The natural history of mosquito-borne diseases is complex, and the interplay of climate, ecology, mosquito biology, and many other factors defies simplistic analysis. The recent resurgence of many of these diseases is a major cause for concern, but it is facile to attribute this resurgence to climate change, or to use models based on temperature to "predict" future prevalence. In my opinion, the IPCC has done a disservice to society by relying on "experts" who have little or no knowledge of the subject, and allowing them to make authoritative pronouncements that are not based on sound science. In truth, the principal determinants of transmission of malaria and many other mosquito-borne diseases are politics, economics and human activities. A creative and organized application of resources is urgently required to control these diseases, regardless of future climate change."

Nov 16, 2015 at 5:46 PM | Unregistered CommenterDon Keiller


How in the world are people still discussing this figure, nevermind repeating the claim it refers to pre-industrial times? Not only is this figure completely wrong, a year and a half ago, this site ran a post about a dispute over a more recent version of Richard Tol's work, a version which completely failed to support his position and was also wrong. It's like the conversation has regressed five years. Where is the skepticism people?

Let's make this simple. First, Richard Tol used a completely inappropriate statistical model which only showed benefits from global warming due to errant data and an extreme outlier. He somehow managed to invert the conclusions of several papers, claiming they found global warming would be beneficial when they actually found it would be harmful. When those data points were corrected, the only data point which said global warming would be beneficial was one of his own papers. Because his model was so heavily weighted toward outliers, it still found global warming would be beneficial.

But then he updated his model with more data. Because the new data had some new outliers of its own, the model wound up finding global warming was never beneficial. That is, by adding more data to his data set, Richard Tol found his conclusions were completely reversed. He even published this result after being forced to publish something like four different corrections due to him constantly putting the data in wrong, so there's no dispute over it.

And yet, we're still here with people referring to the earlier results. Richard Tol has been forced to publish correction to these results which show they are completely wrong, and people are still just using them, because... I don't know.

As for whether the warming is relative to preindustrial times or today, the answer is there is no answer. Different studies used different baselines. They're not comparable. Putting them all on a single graph like Tol has done is completely wrong. Doing so produces nonsensical results. Even worse, Tol knows fully well these studies aren't all on the same baseline, having said so himself. Despite this, he still publishes claims about them being relative to preindustrial times/today.

Nov 16, 2015 at 6:14 PM | Registered CommenterBrandon Shollenberger

Harrabin appears to have used the Tol interview as an excuse to fill it up with as much of his own stuff as possible - like building a giant bund across all of Bangladesh and nuclear war over the subcontinent. He also has mistaken the giant sucking sound of a solar Germany to mean progress.

Nov 16, 2015 at 6:23 PM | Registered Commentershub

Oh, and as for Richard Tol's comment:

Wottsywotts: We've been over this before. The correction do not change the results. The new data points do. The new data points also change the specification and, hence, estimation. JEP allowed a correction and minor update, but not a major update. The major update is here:

The "major update" he's published is garbage. It has tons of problems, but since practically nobody has discussed the paper, they haven't received much attention. One problem which was quickly noticed, however, is Tol inverted another data point. Yes, once again, he took a paper which found global warming would be harmful and listed it as finding global warming would be beneficial.

This rather remarkable fact has been somewhat hidden, however, by the fact Tol secretly changed his paper after the problem was pointed out to hide his error. That's right. After people noticed his mistake, Tol went back and changed his paper without giving any notice of the change. The only way a person could possibly know about it is if they had downloaded the paper before he changed it and kept that copy to compare it to copies they might download in the future. It's pure dishonesty.

It's also garbage work. Anyone who looks at the paper can see the only reason Richard Tol can claim to find global warming is beneficial is once again, there's that major outlier from a paper he wrote. That paper is the only data point in Tol's data set which shows any meaningful benefit from global warming, meaning Tol's conclusion depends entirely upon his model giving extreme weight to a data point he himself created.

Skeptics shouldn't be promoting work by people who rely on dishonesty to hide their mistakes or results which can only be achieved by cherry-picking single data points to give extreme weights. Given that's all Richard Tol has, skeptics should be running away from him. I don't expect they will though. These problems have been obvious for a year and a half now, and it doesn't seem many people care about them.

Nov 16, 2015 at 6:25 PM | Registered CommenterBrandon Shollenberger

Brandon, initially your claim was that Tol allowed his own work to unduly weight the conclusions of an IPCC report, of which he was an author of, and that this violated IPCC rules.

Now you claim that Tol's composite graph is influenced by his own study, and that, in and of itself, is evidence of 'dishonesty'.

Which one is it?

Nov 16, 2015 at 6:33 PM | Registered Commentershub

shub, what in the world are you talking about? You say:

Now you claim that Tol's composite graph is influenced by his own study, and that, in and of itself, is evidence of 'dishonesty'.

But I didn't say anything of the sort. I called Richard Tol dishonest for secretly changing his paper to cover up a mistake he made, nothing more.

As for your implication I've changed my position, that's nonsense. It's true I first got involved in discussions of Richard Tol's work due to his subversion of the the IPCC AR5 report, but that doesn't mean me going back and discussing his earlier errors constitutes a change in position.

Tol gave undue weight to his own work in his model fit in his 2009 paper and several follow-up papers which got him favorable publicity with skeptics because it allowed him to say moderate global warming would be beneficial. I didn't take note of it at the time. Later, when working on the IPCC AR5 report, Tol subverted the normal review process to give his work undue influence in the report. I noticed this and criticized him for it. In the process of doing research on it, I became aware of the fact he had given his own work undue weight in his earlier papers and highlighted that fact as well.

There is no contradiction or change in position. All that happened is I became more aware of how much Tol has consistently been cherry-picking his own work to receive the most influence in things he works on.

Nov 16, 2015 at 6:56 PM | Registered CommenterBrandon Shollenberger

"... Even Arrhenius and Callander, the originators of the manmade warming meme, thought the warming would be beneficial." --JamesG


'[Arrhenius] eventually made the suggestion that an increase in atmospheric carbon dioxide due to the burning of fossil fuels could be beneficial, making the Earth's climates “more equable,” stimulating plant growth, and providing more food for a larger population..." --

Nov 16, 2015 at 8:16 PM | Unregistered Commenterjorgekafkazar


Nov 17, 2015 at 3:29 AM | Unregistered Commenterclipe

Do we really have 58,400 extra malaria deaths each year ?
That's an extrordinary claim Tol makes by saying "it's generally reckoned that malaria incidence would be 10% lower if climate were as it was 150 years ago (and everything else is as it is now)"
and me digging up recent figs for malaria deaths of 584 000pa.
..Im interested in an answer, but I would guess Brandon has frightened Tol away.

Personally I thinks it's OK for Tol to make mistakes, and correct them and it's OK for Brandon to voice an opinion about Tol's's all part of working towards the truth.

Nov 17, 2015 at 8:41 AM | Registered Commenterstewgreen

Brandon does not scare me.

The rule of thumb is 10% more malaria per degree Celsius warming.

For the parasite, this is pretty solid, based on experimental evidence.

For the mosquito, this is shaky, as mosquitoes care more about moisture than temperature.

For the disease, this is contingent on the assumption that there is no change in human behaviour or medical technology.

Nov 17, 2015 at 11:22 AM | Unregistered CommenterRichard Tol

Cheers mate, but "rule of thumb" is not realy good enough, I'd like to see some empirical evidence for that 10% claim.
And it looks like we can't find any.
When I look back at the post here on BH I see has used a small estimate for the number of malaria deaths averted due to climate change mitigation.

Nov 17, 2015 at 12:00 PM | Registered Commenterstewgreen

Indeed, this is based on calibrated models rather than empirical evidence. Note, though, that data on malaria are hard to get and trust. It is a disease of poverty, concentrated in areas where medical reporting is poor.

Nov 17, 2015 at 12:07 PM | Unregistered CommenterRichard Tol

Richard Tol, how do you feel about people like Ridley and the "Bishop" using the figure 1 graph from your 2009 paper without mentioning that it was very wrong and that you have now corrected it very publicly? They and their followers clearly know that the graph is invalid and yet they pretend it is okay. Does that disturb you?

Nov 17, 2015 at 12:54 PM | Unregistered CommenterRaff

Richard Tol says bizarre things. For instance:

Brandon does not scare me.

Nobody said anything to suggest I should frighten him. I'm not a scary person. What I am is a person who has made relatively clear accusations of wrongdoing on his part, accusations he has apparently decided not to dispute.

Tol shouldn't be afraid of me. What he should be afraid of is people catching onto the fact he has systematically cherry-picked and exaggerated the significance of his work across many papers and in the IPCC report, to the extent all his claims global warming will be beneficial are based upon nothing more than one cherry-picked result he himself produced. If skeptics ever act skeptical toward him or his claims, they'll realize much of the work which has made him popular is just a house of cards built upon shoddy analyses designed solely to promote his preconceived notions.

Nov 17, 2015 at 2:19 PM | Unregistered CommenterBrandon Shollenberger

@Brandon .. detect the word 'frighten' on the page
by using ctrl F to bring up "search on page"box in your browser

Nov 17, 2015 at 3:43 PM | Unregistered Commenterstewgreen

stewgreen, frightening a person away doesn't require actually scaring them (it's an expression) but I guess Richard Tol might have been saying I don't scare him, phrased in a general sense, to say he wasn't frightened away in this case? No, that doesn't make sense. Tol clearly made a general statement about my effect on him, not just a statement about this one situation.

Nov 17, 2015 at 4:03 PM | Unregistered CommenterBrandon Shollenberger

@Brandon, take a chillpill, calm down, and avoid errors caused by being gung-ho

..Tol was simply replying to my comment immediately above his
I said - "but I would guess Brandon has frightened Tol away."
Tol replied "@stewgreen Brandon does not scare me." .....that doesn't sound bizarre thing to say at all

* So the actual issue is about this modelling our future world
#1 And think I have spotted a huge flaw *
..about using the phrase "all other things being equal" or as Tol said "and everything else is as it is now"

Well it's not possible is it ? long term modelling of situations which have complex self referencing components is pretty rubbish.

Tol's error is not so much the maths, but in failing to say "The error bars on such models are so huge as to render them pretty useless"

Short-term modelling the world one or two years ahead ...modelling basically works fine.
Then we get some major incident like a world war ..and the model goes in the bin.
cos all those assumptions you made before are have to spend billions on the war, but that brings technological breakthrough, then you have full employment cos of the rebuilding, then you get first a population decrease, then you get a population boom as people have more babies etc .

With 50 year global warming projection models the error bars must be massive.
There you are deciding whether to spend 1 trillion or 2 trillion on measures yet that amount of spending effects the whole economy itself.
We talk about projecting malaria deaths they could be between zero, cos we get a prevention under control with new tech etc.
or levels higher than today cos of some global warming and a magic new strain.
Have models predicted AIDs accurately or Ebola ?
What about if fusion comes on line in 15 years or never ?

#2 The issue is not about a 1C world, a 2C world, a 3C world as we can adapt
So who cares too much about the different economies 1C, 2C etc. ?
... but tipping point into irreversible catastrophe is a whole different thing.

"Catastrophe or not Catastrophe ?" that is the question

- proof of catastrophe : slam the brakes on, CO2 zero, do the geoengineering
- Magic solution like fusion or working CCS comes up ..job done.

The alarmists ROMANTIC thinking seems to be "but if we move out of fossil fuels NOW then it doesn't matter what the true science of CO2 is".
Now that is the crucial model : That would pretty much show us that all out nuclear low CO2 might be possible, but with wind/solar dream you'll never get there in a million years.

Nov 18, 2015 at 4:49 AM | Registered Commenterstewgreen


#1 And think I have spotted a huge flaw *
..about using the phrase "all other things being equal" or as Tol said "and everything else is as it is now"

Well it's not possible is it ? long term modelling of situations which have complex self referencing components is pretty rubbish.

That was about his estimations regarding malaria, not anything I have discussed. You can't just apply a comment in one discussion to published papers written years before that comment was even made.

Tol's error is not so much the maths, but in failing to say "The error bars on such models are so huge as to render them pretty useless"

Uh... no. Richard Tol discussed the errors of the models he used in various papers. It's clear he does not view them this way. And if he did view them this way, it would have been completely inappropriate for him to make any number of claims he made, such as the many claims that made him popular with skeptics - which Matt Ridley repeated. So if you want to claim that's the error Tol made, you have to then say Tol repeatedly made unsupportable claims in both published papers and media statements, to the point most of everything he's ever said on the subject is unsupportable.

Nov 18, 2015 at 6:34 PM | Registered CommenterBrandon Shollenberger

@Brandon, thanks I can see one person reads the crap I write
Yep you understand right, I was aware of all that
..and look forward to someone telling me the error bars are smaller than I imagine.

- On the other matter of whether his newer interpretation shows that warming is bad economically.
* I'll go with the data, not the dogma *
It's no use skeptics holding on to Tol's old graph just cos it was comforting.
, but as I said I 'd like to know what the error bars are ..cos this level of modelling seems fantasy football to me


longer answer
"That was about his estimations regarding malaria"
Yes I did jump around, and started thinking 'are the economic models based on all other things being equal, like the malaria models are ?,Cos the malaria model seems rubbish to me , so I postulate the economic models are rubbish as well'
Of course I was aware he didn't think they were otherwise he wouldn't have published them.
But still I 'd like an explanation.

Nov 19, 2015 at 9:44 AM | Registered Commenterstewgreen

Hey I missed that Richard Tol has gone into full Climate Warning mode
Well the BBC's Chief Climate BIGOT said he has Nov16th
He misuses that quote about 1.1C being the point that warming reaching maximum economic benefits to say that normal people will suffer economic negatives from climate soon

Human societies will soon start to experience adverse effects from manmade climate change, a prominent economist has warned.
Prof Richard Tol predicts the downsides of warming will outweigh the advantages with a global warming of 1.1C - which has nearly been reached already.
Prof Tol is regarded by many campaigners as a climate "sceptic".
He has previously highlighted the positive effects of CO2 in fertilising crops and forests.
His work is widely cited by climate contrarians

Nov 19, 2015 at 3:25 PM | Registered Commenterstewgreen

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