Following my blog post titled ‘Richard Lindzen on Hockey Sticks’ there was some discussion about Richard Tol’s views on various issues relating to economics and the Intergovernmental Panel on Climate Change. Various commentators at the thread where quoting Dr Tol in support of their position. Dr Tol has provided the following response:
“Ian Castles and William Connelley had a discussion about what I said and did not say. Here is my version.
If one assumes convergence of per capita income, and one measures income in purchasing power parity (PPP) exchange rates, then projections of global carbon dioxide emissions are lower than in case one measures income in market exchange rates (MER).
This is the original Castles and Henderson critique of IPCC SRES.
However, emission intensities are also assumed to converge, which partly offsets the above effect.
This was pointed out by Manne and Richels, and by Alfsen and Holtsmark, while Castles and Henderson admitted their initial omission.
As a result, switching from MER to PPP reduces global carbon dioxide emissions, but by an amount that is small compared to the uncertainty about future emissions.
That is, if one is interested in long-term, global climate change, the Castles and Henderson critique is of minor importance.
However, one should worry about the fact that the IPCC, first, made a very basic error and, second, is unable to admit that and correct its way.
If one is interested in climate policy, the Castles and Henderson critique does matter, because the small drop in global emissions is almost entirely due to China and India. The OECD thus shoulders a larger part of the responsibility. The argument of the US Senate, that climate policy without China makes no sense, cuts less wood.
If one is interested in climate impacts, the Castles and Henderson critique does matter, because projected economic growth is slower in developing countries, and vulnerability is larger as a result. Although warming would be slower, impacts may in fact be larger.
If one is interested in regional climate change, the Castles and Henderson critique does matter, because future emissions of sulphur would be different as well, probably higher.
In sum, Castles and Henderson raise five issues, only one of which is of minor importance.
By the way, my reading of the state-of-the-art in economics is that (a) income should be measured in PPP nor MER; (b) there is neither theoretical nor empirical support for the assumption of unconditional income convergence; (c) there is limited empirical support for the assumption on energy intensity convergence.
Richard Tol”
Dr Tol is the Michael Otto Professor of Sustainability and Global Change in the Departments of Geosciences and Economics at the Hamburg University, Hamburg, Germany.
Jennifer Marohasy BSc PhD is a critical thinker with expertise in the scientific method.
“The argument of the US Senate, that climate policy without China makes no sense, cuts less wood.” -Tol
Ignore the steaming piles of elephant dung in the corner, it is these mouse droppings that we should worry about.
You don’t have to be a scientist or politician of any sort to see how totally bankrupt Tol’s claims are when he ignores China’s contribution to antropometric atmospheric emissions. Dirty coal, wood cooking, massive hydro, rice paddies, animal practices, waste water treament, industrial practice, population size none matter, what matters is fair share based on economic exchange rates. And if the US dollar plunges? Will Dr. Tol be at the forefront proclaiming the US doing more than its’ fair share? Don’t bet on it and understand this is high stakes gambling and Dr. Tol is cheating to win.
Robert , I can’t see how Tol is sying the words you put in his mouth. Why not concentrate comments on what the post is actually arguing about : to me it seems to be saying that there are several significant aspects of economic change where the IPCC has to get it’s economic modelling in better, more realistic shape. Isn’t that a central part of the scenarios, not a minor part? i.e. not mouse droppings.
I did not put words in his mouth, I QUOTED him. Tol also dismisses the Castle, et al criticisms as being 4 of no importance and one of only minor importance. The IPCC SRES is fatally flawed and the response is for the defenders to circle the wagons.
My point is to emphasize that any AGW discussion of future action that excludes China is doomed from the start. It takes a particular effort to be dumber the the US Senate but Tol manages the feat.
Maybe were talking at cross purposes, and I agree that China cannot be left out of policies that attempt to manage CO2 emmissions; but doesn’t Tol’s argument for correction of the model’s lack of economic realism (as I understand it) implicitly say China needs to be factored in. Maybe we’re both thinking the same thing and your forceful faecal metaphors are confusing me.
I had to look up “faecal.” Fecal around here. My understanding of Tol is that he dismisses the switch to PPP equivalence as being a minor point at best. He still defends the IPCC SRES which I find wholly unrealistic. You will notice as well that he needs to stay focused on CO2. That’s to be expected. Look at the list of Chinese behaviours I list. I didn’t even mention CO2. The IPCC and its defenders are dedicated to ignoring anything that cannot be associated with western consumption. We know airborne particulates are nasty at every level but western economies are decades ahead in controlling PM10, PM2, etc. We know how to fix particulates and we know how much it costs and it is cheap BUT even though the cost benefits and total costs are orders lower we refuse to address particulates because they impact developing economies. This is about wealth redistrbution not AGW.
Robert Cote, You’ve misread Tol’s post. He’s not defending the IPCC, he’s criticising them. He’s not dismissing the Castles & Henderson criticisms of the Panel, he’s supporting those criticisms. He’s not saying that 4 of our 5 criticisms are of no importance: on the contrary, he’s saying that they ARE of importance.
In my opinion your argument about particulates is correct, and I’ve made it myself. It is just one of the many reasons why the Kyoto Protocol is wrong-headed and counter-productive.
I should point out that Richard Tol’s criticisms of the IPCC come from a position of strength. He was a lead author in the IPCC second assessment report, a coordinating lead author in an intermediate report and again a lead author in the third assessment report. He told the House of Lords Committee that in recent times things at the IPCC ‘have become more and more political.’ And he explained the political origins of the SRES projections as follows:
‘Going back to the convergence assumption, from the very start onwards it was clear that the SRES team had placed itself under constraints of political correctness, that is to say because it is an IPCC exercise it has to be reviewed by all the governments in the world, and if you come up with scenarios in which the African countries, which are a fairly large bloc (in the UN) – if they do not grow fast enough, they will never approve our scenarios.’
Surely this evidence from an expert who was at that time an IPCC insider reflects upon the realism of the scenarios. Yet there is no sign that the IPCC has even considered the question. Its Chairman, Dr. Pachauri, gave evidence to the Committee on the same day as Professor Tol, and said in reply to a question from Lord Skidelsky that the criticism of the IPCC’s methodology ‘only validates the methodology that the IPCC used earlier. It does not require any deviation from it.’ Our criticisms have not been considered: they have been swept outside without examination.
While on the subject of the IPCC emissions scenarios, contributors to this blog will remember that John Quiggin sought the comments of Erwin Diewert, Professor of Economics at the University of British Columbia, on a review of the Castles & Henderson critique that he (JQ) had posted on his blog.
John rightly said that Professor Diewert is ‘the leading researcher in the theory of index numbers for the last thirty years’, and posted the initial version of Erwin’s comment (dated 28 March) on his website together with some observations of his own.
On 8 April Professor Diewert wrote to Professor Quiggin, and copied to me and to David Henderson, a message that included the following:
‘Ian Castles sent me several very useful comments on my note and so I have revised it a bit in the light of his comments. I would appreciate it if you could replace the previous version of my comment on your website with the attached version.
‘The changes I made are as follows:
‘Footnotes 1,2 and 3 are new. Footnote 1 just thanks you and Ian for your comments. Footnote 2 just adds a few more key references to the work of Castles and Henderson. Footnote 3 just notes something that I did not say explicitly before and that is that all of these convergence hypotheses are pretty questionable (and refers to Stegman and McKibbin to back up this belief) but that is not the main issue that we are addressing in our interchanges; i.e., we are proceeding as if convergence is going to occur and looking at how best to model the emission consequences of the assumed convergence.’
John Quiggin has not as yet replaced the earlier version of his note with the revised version that Erwin Diewert sent him on 8 April. For those who may be interested, the revised version is posted on Professor Diewert’s website: Click on ‘Other Papers’, and follow the link to ‘2006’ and thence to the comment.
The key points that emerge from the note are (a) the three conclusions, which boil down to saying that Diewert, Castles, Henderson and Quiggin all agree that the SRES scenarios should be redone; and (b) the new footnote 3, which essentially cites the paper by the ANU researchers Alison Stegman and Warwick McKibbin in support of the argument that the IPCC convergence hypotheses are in any case ‘pretty questionable’ (i.e., even if the IPCC modellers had used analytically sound procedures – and we all agree that they didn’t – the emissions scenarios would still be unrealistic and therefore unsuitable for the uses to which the IPCC has put them, including the modelling of the future climate).
Although the Stegman & McKibbin research was funded in part by the Australian Greenhouse Office, it is not cited in the AGO’s article on the IPCC Scenarios in its ‘Hot Topics on Climate Change’ series, nor are the recent Castles & Henderson papers that have now been cited by Erwin Diewert. These papers are also ignored in Barrie Pittock’s book, and in a review recently published in ‘Climatic Change’. I wonder why.
IPCC’s high-end (A1FI) “scenario” has world consumption of (carbon-rich) coal growing by an amazing 37% between 1990 and 2000. In reality it grew only half as fast – 21% during 1990-2004. Thus even by IPCC’s own dubious methodology, the high-end 5.8 degrees C of warming “projected” for 1990-2100 needs downward revision in AR4 (due in 2007). But humans are only a minor influence on our ever-changing climate, because climate is dominantly solar-driven, not people-driven. IPCC would serve humanity better by seeking answeres to crucial questions like: When will the next Little Ice Age cold period arrive? When will the Indian Summer Monsoon next fail? How will energy-short Western Europe stay warm during a return of conditions like the Maunder Minimum “quiet Sun” of 1645-1715? How will a billion people on the subcontinent be fed if there is no rain for three years? Lives will depend on timely warning; and fortunately, the timing of future solar impacts can be calculated. Predictions not “projections” are what planners need.
I was going to say something until I read fosbob’s eloquent comment and realized I couldn’t say or add anything to that.
Ender, Jonnyboy, what about you guys. Do you agree with me?
Joe, I dare anyone to go to an election flying the global warming flag. In fact I double dare the ALP to go to the next election on a platform of Kyoto, wind farms, striped parrots and global warming.
Should be another spectacular ALP loss.
Rog
Don’t put it past them and I can’t wait. However I think they’ll try that stuff by stealth. That’s why they can’t be trusted.
Ian Castles has a nasty habit of stepping over the squashed bananas to display the cherries. If you read further of gis various sources you invariably stumble across other statements that do not support him. Raise them though, and he’ll quote extensively and so profusely and boorishly that you’ll regret that you did because his responses are heavily engineered to rebuff and obfuscate, not learn or share. Ian knows all, his footwork is practiced, his sword gleaming and his stance determined.
Rather than waste time in a frontal with the nine-headed beast we can quietly acknowledge why his tiresome and repetitive arguments have generally won the reception they have. We can also be clear why he has found the dire need to move from specific criticisms of particular assumptions to more general attacks of the broader IPCC process. His aim is to discredit the IPCC and to argue against AGW. Nothing more noble than that. Thus, having jabbed successfully, he now expands in a series of flank attacks to encircle all related issues.
And the proof, Digger, of your little outburst is what exactly?
Al Gore had Ohio speechless;
“Two hundred years ago this summer, at the sunrise of America’s first full century, veterans of the American Revolution came here and founded Smith County. In their minds’ eye, the very idea of what America could become was still then a barely discernible horizon.”
“(my father) saw a horizon in which his black and white constituents shared the same hopes in the same world…. His last election was lost — but his conscience won.”
“Each of us has our own sense of the next, finer horizon.”
“America always looks forward, to the next horizon.”
“Just visible within a generation’s journey is a new horizon”
“And I know that with our history as our rudder and our ideals as our compass, we can reach our new horizon.”
“And I see on the horizon an America where people with disabilities are fully respected for the abilities they have, everywhere in this land.”
“Come with me toward America’s new horizon. Across that horizon stands the promise of our common values and prosperity – of strengthening every family, lifting every child, leveling every barrier, leaving no one behind.”
“Here, at the center of my home town, in the heart of America, in the midst of the people I love – that is the new horizon I see”
http://www.4president.org/speeches/gore2000announcement.htm
Sorry, wrong thread!
My second-to-last sentence should have read:
In sum, Castles and Henderson raise five issues, one of which is of minor importance, while the other four do matter.
I did not say that China’s emissions are not important. I only said that per Castles and Henderson, China’s future emissions may be lower than the IPCC would have us believe.
Thanks Richard. Actually I felt you points were quite clear in the first version I read and there was really no need for the confusions.
As I read you, I understand that a lot more sophistication could go into economic modelling aspects of carbon dioxide emmissions, and this could yield a stronger platform for policy decisions.
cheers DaviT T
Hello
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