Wednesday
Feb292012
by 
Bishop Hill
Bishop Hill Nordhaus and the sixteen
Feb 29, 2012 Climate: Models Climate: Statistics Climate: Surface Climate: WG2 Climate: WG3 Climate: other Economist William Nordhaus takes a pop at the sixteen concerned scientists, in the latest skirmish kicked off by their Wall Street Journal editorial.
My response is primarily designed to correct their misleading description of my own research; but it also is directed more broadly at their attempt to discredit scientists and scientific research on climate change.1 I have identified six key issues that are raised in the article, and I provide commentary about their substance and accuracy. They are:
- Is the planet in fact warming?
- Are human influences an important contributor to warming?
- Is carbon dioxide a pollutant?
- Are we seeing a regime of fear for skeptical climate scientists?
- Are the views of mainstream climate scientists driven primarily by the desire for financial gain?
- Is it true that more carbon dioxide and additional warming will be beneficial?
Reader Comments (130)
Here is what looks to me to be a sensible policy. Dig out the history books, study the reconstructions of temperature and any other met variables, look at historical patterns over say tens to many hundreds of years, and suppose, for the sake of decision-making, that they will at least roughly repeat. Build up a picture of the range of climate conditions you can, on that basis, expect for your part of the world. As and when you have the wealth to do something about it, modify your house, your land, your business ideas, your roads, railways and towns, to be able to handle more of that range of conditions.
You now have the basic plan that those who believe in computer model predictions of complex, poorly understood systems will have to beat. They will say you have to protect against floods. Well, you knew that already. They will say you have to protect against droughts. Well, ditto. And ditto for ice and snow and glorious sunshine.
Then they might say, ah but we can give you power beyond your wildest dreams if only you will follow us. We believe we can control the climate by varying the amount of a trace ingredient (commercial secret) in the air!! We call it Control Opportunities Squared, or X for short. What temperature would you like? A little cooler perhaps, then less X. A little warmer, then more. Actually, the sales pitch is simpler than that - it is for more of what you like and less of what you don't like, turn down the X. Look we have armfuls of print-outs to prove it! But of course, you'll need to give us a heap more money, not to mention control over your life, if this is to come to pass. We need better computers, we need to maintain societal vulnerability by destabilising power supplies and scaring school kids (reaches their parents you see), and we need it all now! Whoops, got a bit carried away there...That was not for general release - it was the marketing pitch for leaders. For you poor folks out there in blogland or poundstretcher or wherever it is you gather, we say walk to work, change your lightbulbs (actually, we insist on that), turn off your TV sets at night, only boil just enough water for your coffee, stop eating meat (you won't be to afford it soon anyway, so why make it hard on yourself), and don't get involved with anything energy-intensive like building cars, trains, power stations, roads, and so on. Oh, and be on the look out for climate hate speech! That's anything anyone anywhere raises that might just be a tiny bit on the embarassing side for us. They are anti-climate, and they are to be denounced.
@ Gecko
I averaged the predictions and estimated my exped increase in total wealth next year as $3 million.
This is precisely why nobody respectable uses the average of forecasts, in a commercial context. If you have one forecast of $1million and another of $5million, at least you have two forecasts with some thought behind each.
Nobody, however, agrees with or has forecast any $3million average. So why use the average? Who says it's a good idea or a likely outcome?
if the actual outcome emerges anywhere less than $2million or greater than $4million, then the better choice would have been either the $1million or the $5million guess, because they are either better estimates or at least no worse than the average.
Obviously one may not know which of the two looks the better forecast, but this is not an argument to plan on the average of the two outcomes to happen. Instead it's an argument for planning on no change at all. The insoluble uncertainty in the range of forecast outcomes means that betting on $3million is certain to be wrong, and anyway assumes a forecast is needed.
It is analagous to saying that if my head's in the oven and my feet are in the freezer, then on average I am comfortable.
The more I hear about how these people think the more gobsmacked I am.
Ah, 50 comments per page now, I see.
[BH: Unfortunately, that's the maximum]
Personally I believe CO2 to be a positive externality and farmland should be taxed to subsidise oil users.
John Shade:
That's always a sensible policy! But having a benchmark from history for regional climate models to beat is essential, agreed.
William Nordhaus is stepping deeper into chemistry than he realises. I could easily construct many more castles in the air that he would be uncomfortable with.
For example:The tortuous reasoning that CO2 is a pollutant can also be used to claim that oxygen (O2) is a pollutant. Ozone (O3) is synthesized from O2 in the atmosphere by sunlight. Ground level ozone is also produced. Ground level Ozone is, quite rightly, described as harmful to humans and other life forms at concentrations much lower than CO2. Photosynthesis by vegetation produces oxygen, which produces ozone. Ergo plants are harmful to the environment.
Unless, that is, William Nordhaus would like to describe sunlight as the pollutant. I really would enjoy seeing an attempt to paint the sun as being harmful to the environment.
You raise a vital point. It all depends what you mean by the environment. The temperature of darkest space is 2.7 Kelvin. Surely that is the most ubiquitous environment there is. The sun has a lot to answer for.
"..... dig out the history books ....."
I am very much looking forward to eating the grapes grown in Bishop Aukland, as in the Roman Warm Period - much preferable to another ice age.
It is interesting that when economists, physicists, engineers, geologists, meteorologists, etc. write sketpical articles about the AGW consensus, the first rationale to dismiss them is that they are not climate scientists.
Yet here the NYT is giving a whole column to an economist to defend the consensus as if he is the most credible person in the world.
His claim of warming is not quantified.
And of course his infantile definition of CO2 as a pollutant is not challenged, his claim of human climate influence is unquantified, and by use of the red herring of financial gain- instead of the real motives for academics, peer recognition and social capital- are ignored.
And his graphics are of the most extreme- and frankly misleading sort, and produced by the people who are benefiting from them.
'"He seems to believe that Iceland is part of Europe"
http://en.wikipedia.org/wiki/File:Europe_orthographic_Caucasus_Urals_boundary.svg
So: do you believe that Iceland is on the European continental shelf? If not, why are you pratting about?
"I have identified six key issues"
Utterly false strawmen. Those are not key issues. There are two key issues:
1. Is the Earth's current climate outside the bounds of natural variability of the current interglacial?
2. Is Earth's climate dynamically unstable (has "positive feedback") to temperature perturbations?
Until those two issues have comphrensive scientific evidence (not models or fraudulent "hockey sticks") that the answer is 'Yes' to both, there is no justification for the draconian political policies promoted by "climate scientists" (who aren't actual scientists, since they refuse to follow the Scientific Method).
Very neatly put, AndrewSanDiego.
At the risk of being slightly repetitive about this, I still have not had an answer to my question to Richard Tol.
I am not just being facetious, I really would like to know why so many economists, politicians and environmentalists call CO2 carbon when they are two completely different things. I have wondered about this for years.
Does anyone know the answer?
Feb 29, 2012 at 6:41 PM Barbara
"CO2 carbon when they are two completely different things. I have wondered about this for years.
Does anyone know the answer?"
Because they learned it by rote, not by thinking about it and understanding.
Nordhaus: " Beginning in 1953, the largest tobacco companies launched a public relations campaign to convince the public and the government that there was no sound scientific basis for the claim that cigarette smoking was dangerous."
Perhaps they did that because there wasn't a sound scientific basis. People may complain about the inadequacies of climate science, but tobacco science is far, far worse.
@Richard Tol
There is a certain level of insanity in the way you assess the impacts of climate change - the principle seems to be, since we don't know what the actual impact is likely to be, then we must prepare for all possibilities! There also seems to be a presumption that whatever climate change occurs WILL be the result of CO2 emissions, therefore the one thing that we must do is to reduce CO2 emissions. The longer history of our climate appears to indicate other sources of climate variation.
Given the current level of uncertainty, it isn't clear to me that come 50 years in the future we could look around us and have any idea whether reducing CO2 emissions had achieved anything. We could be pretty sure how much it had all cost us - between the Carbon taxes, the costly alternatives to fossil fuels and the costs of adaptations (many of which would turn out to have been useless) - but the benefits will be impossible to assess. Further, this also seems to assume that all the effects of Climate Change are negative - an unlikely proposition.
Nordhaus writes with all the authority and insight of someone living in
a cave in Afghanistanan ivory tower.@Barbara: I think we can discount the use of "carbon" for the purpose of abbreviation, since "CO2" serves very well for that, but there is a well practised agitprop/Gramscian Marxist technique whereby you rename things in order to reshape how people think about them. It's quite clever really; "CO2" is an odourless, colourless invisible trace gas that is so vital that life on earth cannot survive without it. "Carbon" on the other hand, is a nasty sooty dirty solid, and in its pure evil form of "carbon black" it is even a potential carcinogen. "Carbon" is quite clearly a nasty pollutant.
But perhaps I am being excessively cynical. There is always the possibility that the Richard Tol's fellow travellers in the CAGW industry are simply making a category error.
Up until a few moments ago, I had considerable respect for Richard Tol, but he has apparently ceased using reason and logic.
Nordhaus very strongly reminds me of a very scary Baptist pastor who spoiled a number of perfectly nice Sundays during my youth, by invariably preaching sermons during which I could almost smell the fire and brimstone; he told us Boys Brigade members, who only came within his orbit due to the compulsory monthly Church Parades, that all of us were on the road to the fires of Hell. Unless we did as he said.
Economist William Nordhaus said,
I have identified six key issues that are raised in the article, and I provide commentary about their substance and accuracy. They are:
■Is the planet in fact warming?
■Are human influences an important contributor to warming?
■Is carbon dioxide a pollutant?
■Are we seeing a regime of fear for skeptical climate scientists?
■Are the views of mainstream climate scientists driven primarily by the desire for financial gain?
■Is it true that more carbon dioxide and additional warming will be beneficial?
= = = = =
All,
As for Nordhaus’s set of questions to the ‘16’ scientists who authored the Wall Street Journal editorial, if I disregard any of his implications of 'a priori' AGWisn in unstated premises and his lack of balance in posing the set, I offer an arguably better set of questions put rather casually in an ad hoc fashion as follows:
1) What are the open science based (non-IPCC) and objectively selected criteria for theoretically and empirically showing which climate parameters are necessary to adequately quantify what the changes have been in the balanced/unbalanced Earth-atmosphere system for all sets of timescales including scales of billions of years down to scales of decadal length.
2) Based on 1) what is the significance in magnitude of the changes of those climate parameters to the balanced /unbalanced Earth-atmospheric system in the modern (last ~150 yrs) era evaluated against the overall longer timescales?
3) How to identify theoretically then then empirically measurable dependence of one parameter on another and also on the balance/unbalance of the Earth-atmospheric system over all timescales.
4) How to attribute the cause of modern era parameter variations if some or all of them; a) fall within the longer scale parameter variations or 2) fall outside the longer scale parameter variations?
5) Then, look at misleading questions like: Whether CO2 is taken as a presumptively dangerous parameter.
Much more work by science independent of the IPCC centric is needed.
John
Barbara,
It's purely a marketing issue. "War on Carbon" is snappier than "War on Carbon Dioxide".
Note that they switch to measuring carbon dioxide when measuring emissions because the numbers sound bigger and scarier.
If I burn 12 tons of carbon I get 12 + (2 x 16) = 44 tons of carbon dioxide.
Scary. Especially if I frame it as "pumping" carbon dioxide into the atmosphere. I don't pump it - it kindof wafts out of my car exhaust and I also breathe it out.
AndrewSanDiego hit the nail squarely on the head. Why on earth give Nordhaus's set of strawmen credence by debating them?
The facts don't fit his assertions. QED.
Barbara,
Oil, natural gas and coal are not themselves CO2. But when you burn them they combine with oxygen and form CO2. This happens (of course!) because they all contain carbon. So I think 'carbon tax' is a shorthand for 'tax on fuels that contain carbon and thus produce CO2'. Imposing a tax on fuels is something governments find easy to do. Imposing a tax on CO2 volumes directly would not be. Uranium is a fuel but it does not contain carbon (hence tax-exempt). Diamonds contain (are) carbon but they are not used as fuel (hence tax-exempt). I don't share Richard Tol's enthusiasm for a carbon tax but I don't think the terminology itself is unreasonable.
Jane Coles: "So I think 'carbon tax' is a shorthand for 'tax on fuels that contain carbon and thus produce CO2'."
Then that would include almost all the food we eat. For it also contains carbon, and produces CO2. Are they going to impose their carbon tax on food?
Don't know if anyone's mentioned this, but none of Prof. Nordhaus' plots include physical error bars. His plots as presented are scientifically meaningless, and prove nothing more than that Prof. Nordhaus plain doesn't understand experimental science or the impact of accuracy-related error bars on the meaning of data.
If he did pay attention to physical error, Prof. Nordhaus would have discovered that the surface air temperature record is probably no more accurate than (+/-)0.5 C, and that the physical uncertainty of climate models exceeds 10 C after 10 years.
His entire analysis is a crock. It's perhaps not exceedingly surprising that Prof. Nordhaus might make such a fundamental mistake in science. His expertise is in economics, which is most attentive to random errors. Do economists ever use instruments to actually measure anything? Or is it all just data-gathering?
In any case, random errors necessarily diminish as 1/sqrtN in large data sets. Temperature measurement errors and climate model errors are systematic. Systematic errors do not necessarily diminish in large data sets. They typically propagate as (+/-)sqrt[(sum over N errors)^2/(N-1)] and so can become larger as N increases.
I recently posted an analysis of stable isotope dO18 temperature proxies here (braving defensive flak-fire), and it turns out they're infected with unappreciated systematic measurement error as well, of about (+/-) 2 C. Neglect of physical error is pandemic in AGW-related climate science and, apparently, in its supporters.
I propose a corollary to Godwin's law.
As an online discussion CAWG grows longer, the probability of a comparison involving Big Tobacco approaches 1.
"Our work, if correct, would justify a modest carbon tax."
And if your work is not correct?
And what's a "modest" tax?
Aiui, top rate income tax is currently 50% (was 95%). Has Napolean not yet been defeated?
@Justice4Rinka Feb 29, 2012 at 3:30 PM
Oh, no! It's worse than we thought. We must all start reducing our comment footprints now. And in the interest of "sustainable commentary", perhaps a "comment trading system" could be established. ;-)
@Barbara
I don't know. The convention to work in tonnes of carbon rather than tonnes of carbon dioxide was agreed before I started my research. The difference is 44/12. Things get a bit confused when methane is thrown into the mix.
@A number of others
Nordhaus and I may be economists by training, but we have had many conversations with physicists and chemists.
When confronted with an uncertain situation, you weigh the probabilities and make a decision. That decision may be that you need to wait for extra information. However, learning is slow in climate research, and it takes rather a long time to affect climate change through greenhouse gas emission reduction. Therefore, in a problem like this, you want to start acting now and revise your plans as you learn more.
Richard, that is as maybe, but in the meantime we have increased energy and living costs for the 50% of the world's population who live in the relatively cold northern hemisphere. And held back the provision of cheap electricity to the people who urgently need it in the developing world. (Do you know how many people die every year from wood smoke cookers)? Biomass fuels have already adversely impacted global food production, and increased the price of staples for millions. And all this is based on models which are so full of holes, dubious assumptions and dodgy data, put forward by literally a few dozen activist-scientists who somehow gained much more influence than their intellect merited. As others have said, history and numerous scientific studies have shown that it was warmer in the MWP, and not just in Europe. Likewise the Roman, Minoan and HCO. There is no empirical evidence that increasing CO2 has or will have any adverse or significant climactic impact. All we have seen in the last 150 years is a long slow thaw after the little ice age. This crap has to stop, and stop now, before any more harm is done to humankind (and science, and the environment - if if just a little money wasted on CO2 alarmism was spent on real environmental problems, like over fishing of the oceans, pollution of land and sea by heavy metals, the world could be a much better place for millions of people. But the first objective should be clean water provision (and a cash-for-weapons collection programme) for the developing world. Sorry Richard, nothing personal, just need to rant now and again to keep sane. By the way, you are in Dublin yes? Have you seen how the historical temperature data for the station at Dublin Airport has been adjusted by GCHNv3 and GISS (compared with GCHNv2)? Truly shocking. Ask BH for my email and I will send you the gifs.
This profile throws some light on William Nordhaus' background and thinking:
http://www.pnas.org/content/103/26/9753.full
Note the para 2 reference to ' ...potential to shape economic behaviour and environmental responses...'
lapogus.
I couldn't have put it better. Though I have said the same repeatedly for several years. I would only add that Richard Tol's argument that "you want to start acting now and revise your plans as you learn more" is fallacious.
For a start it assumes that it is necessary to reduce greenhouse gas emissions and continues by assuming that it is possible to reduce greenhouse gas emissions without creating a situation which will be broadly to the disadvantage of mankind.
While it is fashionable to accuse the sceptics of "experimenting with the planet" I contend that the experiment is actually being carried out by the climate change enthusiasts who have no empirical evidence to support any of their arguments as they consistently tweak their data, re-program their models and refuse to accept the evidence of their own eyes.
To go down the route he suggests means you are trying to solve the next generation's problems (or more likely the second generation's problems) with today's knowledge and therefore today's technology which is certainly an experiment that may well prevent our grandchildren from taking the steps — should they become necessary — to adapt to a world which may be a couple of degrees warmer or may be several degrees colder.
Our forbears were quite happy to live their lives as it suited them and leave their descendants to solve their own problems. Considering that we are healthier, longer-lived, better-fed, better-educated, and in general possessed of all the benefits that those conditions imply, and considering that the greatest flowering of invention, science, technology, arts, culture and general human well-being has happened during periods when the climate has been at least as beneficial as it is now I have every confidence that the generation of my as-yet-unborn grandchild and his/her contemporaries will be at least as far in advance of my generation in its ingenuity and ability to solve its problems as mine is by comparison with my grandparents'.
Provided we don't **** it up for them by trying to be clever!
Richard, I am glad you are not a general.
[We got an intelligence report that there might be a terrorist cell in New York, so pursuant to the precautionary principle we bombed the city to the ground. Sure, we did trillions in damage and killed a few million people, but if there really were terrorists there, we got them. We could have waited until our information was more accurate. And we might have chosen a different way to neutralize the enemy, but we wanted to get started right away on a problem like terrorism.]
@Lapogus, Mike, Stan
Lazy thinking is fine for the anonymice of the blogosphere. Nordhaus, being one of Yale's best, is held to a higher standard.
Richard
It would be nice if you could point out precisely which of our arguments is "lazy thinking".
I am arguing from several millennia of human experience while it appears to me that you are taking at face value the argument that "this time it's all different" without any empirical evidence on which to base that judgement.
Personally I think Stan's argument — while perhaps extreme — encapsulates the position quite clearly. What is being proposed is bordering on overkill in the light of our current ignorance of precisely what climate is likely to do over the coming century combined with the eco-activism of those who — whether they are right or wrong in their diagnosis — will continue to prescribe the same anti-civilisation, anti-scientific, anti-development, anti-human medicine because that is the way their minds work.
Gleick and his choir are perfect examples: my way or no way — correction: my way or else!
@Mike
If you can show that greenhouse gas emissions are a negative externality, you have made your economic case for greenhouse gas emission reduction. There are some 60 peer-reviewed studies that show this, and 0 that show the opposite. So, the burden is on you to argue that these studies are wrong.
You argue against the possibility of harmless climate policy. That's a nonsense argument. Climate policy will cost money. The question is whether it is worth it. See above.
That said, climate policy need not cost a lot. Norway has had a carbon tax for 20 years now.
Richard, I appreciate you are busy and that you make time to make appearances here, but I too would also appreciate if you could outline where my/our thinking has been lazy. Btw, I commend you for your comment on Gleick's idiocy; if only a few other prominent people in the climate field would have the guts to call a spade a spade we would all be further on.
I have just refreshed before posting the above and seen your reply to Mike, where you ask for us to prove that CO2 is not a negative externality. But what is the evidence that CO2 IS a negative externality? To my knowledge it is a natural compound gas, which is not toxic, and is actually essential for life on the planet. It has a very minor role as a greenhouse gas (7-11% off total effect), which due to it's logarithmic properties effectively means that any increase of its atmospheric concentration beyond 360ppm is going to make bugger all difference. And that's if you go along with the consensus view on atmospheric physics, which I would say is far from settled science, especially with the recent interventions by Harry Dale Huffman, Nikolov and Zeller and more recently Stephen Wilde. Solar-magnetic and long term oceanic cycles which climate models don't even address just add another level of uncertainty to the science.
So I would suggest that it is up to you and other fearmongers to first demonstrate scientifically that the answer to AndrewSanDiego's questions are affirmative:
Citing 60 pal-reviewed papers of environmental-activist groupthink is just not good enough and a distraction from the fundamental issue, which is that CO2 induced AGW is at best a half-baked thesis, unsupported by any empirical scientific observations.
@lapogus
Answers: Probably no. Definitely no.
Does not take one iota away from the case for greenhouse gas emission reduction, which rests on negative externalities.
I'm sorry, Richard, but I think the argument depends on your definitions.
Just as the assumptions programmed into models (climate and otherwise) will influence the outcomes and your interpretations of them so the extent of negative externality depends on your initial assumption.
The peer-reviewed studies you refer to (I am assuming we are talking about the same ones) draw negative conclusions about the effects of CO2 but these conclusions are based on the initial model assumptions of a *3 positive feedback for a doubling of CO2 and then go on to make certain predictions (let's stop pretending about them being "projections", shall we — these are the results that the eco-activists want to make sure government believes to be true) which in the view of many sceptics are dubious to say the least.
There is no empirical evidence, whatever the "peer-reviewed" science might say, that greenhouse gasses are in fact a negative externality and increasingly I am seeing research results — whether "peer-reviewed" or not — that argue that the likely adverse effects of CO2 are overblown.
On that basis I am not prepared to put future generations in hock because of the ecological/scientific fad du jour.
And having just seen lapogus' 2.57pm posting and your reply I am puzzled by your response.
If current climatic conditions are not outwith normal variation and the climate is not "dynamically unstable" on what basis is CO2 a negative externality given that it is essential for life (all forms of life, as I understand it) and that much of life on earth would benefit from a fairly substantial increase.
Agreed there could come a point at some indeterminate time in the future when some form of mitigation might need to be considered but I see no evidence that that state has yet been reached or will be on the sort of timescale which would require action within my lifetime or probably that of my children.
Beyond that, I submit, this generation is not qualified to have an opinion since we will almost certainly get it wrong.
Incidentally, like lapogus I am extremely appreciative of your giving up your time to come along and debate with the anonymice but I'm not so sure about the 'lazy thinking' bit. I may be a bit out of practice but it's not for want of putting in the effort!
Okay, but what is and where is the evidence for CO2 being a negative externality?
If mankind had not been burning carbon based fuels to keep warm and provide energy for industrialisation, mechanisation and the creation of wealth for the last 300 years we woull all be much worse off. Sure things could have been done better, but I think most would agree that it is better to be here now than back in the dark ages. Do you know the hours farm workers had to work just to make a subsistence living in Scotland in the 18th century? Crofters likewise. Industrialisation could have been done much better and I don't see how post-industrialisation is going to be a panacea, but I for one am glad I don't have to bring my kids up in the 18th, 19th or even early 20th Century. Coal, oil and gas, whether we like it or not, have made life better for just about everyone they have reached. You are an economist, please show me where the dis-benefits of CO2 emissions have outweighed the benefits.
Or do we just have to take the corrupted and discredited IPCC's word for it?
@Mike
Carbon dioxide is a negative externality if you consider the full range of possible atmospheric feedbacks. It is not for cherry-picked feedbacks, but that is neither here nor there. Carbon dioxide is a negative externality also if you include the positive effects of CO2 fertilization. Carbon dioxide is a negative externality if the system is dynamically stable (and an indeterminate externality if not, as shown by Keller). And modern decision theory does not, of course, hinge on statistical significance let alone on the elimination of alternative explanations.
OK, Richard. I'm with you so far and I take the point.
But is it realistic in the real world to do that? As a politician who has to make life and death and all sorts of other decisions — and boy!, am I glad I'm not! — this is not what I want to hear. You, Dr Climate Scientist, are supposed to be an expert and that is the best answer you can come up with? Narrow the uncertainties a bit. And, I add, where is your empirical evidence? You tell me you have peer-reviewed studies. I say I am seeing other studies, which may not be peer-reviewed but which are casting doubt on what you are telling me and the only answer you can give me is a variation of 'the models say so'!No-one should be expected to take action on a hypothetical worst-case scenario. So I ask Dr Climate Scientist to expand a little and tell me:
What is it that makes CO2 a net negative externality given that everything that I actually know about it suggests otherwise.
{I don't know enough about 'modern decision theory' to make intelligent comment but I believe there is a very good introduction to the subject by Sven Hansen which I shall look at}
Richard Tol at 3.36
Richard could you please put that into plain English?
Many thanks.
Mike Post
So all this all hinges on an a conditional, that the range of possibilities effectively depend on conjecture that water vapour is indeed a positive feedback, which, given the net cooling effect of increased cloud cover in the tropics and mid latitudes (where most energy from the sun is received) is a highly dubious assumption to say the least.
As Mike says, is this the best you can come up with? Hats off to you for coming here and engaging, but AGW is rapidly being shown to be a groupthink tragedy. Lazy thinking indeed.
It's this "full range" of possible feedbacks that's got me worried. I can probably say that about a couple of hundred things that I make decisions about every day of the week.
If we allowed ourselves to follow the modern version of the precautionary principle we'd never get out of bed. But wait a minute! Don't more people die in bed than anywhere else? What I sense happening is that the precautionary principle (and for all I know 'modern decision theory') is replacing common sense and a sense of proportion.
Simply to say something has negative externality is not per se a good enough reason for taking the sort of extreme action we are being expected to "nod through" with regard to climate.
The "full range of possible atmospheric feedbacks" is a fairy tale. It is a made up range of numbers. In the world of fairy tales anything you don't like "is a negative externality".
In support of Mike Post, can we please use plain English. It's not that I don't trust you. It's just that I don't trust what you are saying.
"Negative externalities"
Jargon, conceived for its ambiguity.
The only real question is, does increasing CO2 have a net negative or positive effect? Richard Tol wants to cite 60 peer reviewed papers in support of the "negative externalities" of global warming.
I'll start by citing 2,700 deaths this winter because of extreme cold.
I might also point Richard in the direction of Lindzen's easy-to-understand work that shows climate sensitivity has repeatedly, over decades, refused to conform to the ~3C hypothesis. The observed effects may be a transitory sensitivity but no-one has satisfactorily explained where the 'missing heat' actually is, beyond hand-waving. The excuses - for that is all they are - include deep-ocean down-welling managing to completely bypass every single ARGO bouy on earth. (That fell from favour when it was pointed out that sea levels were not in fact rising faster, due to thermal expansion, but falling slightly. Oops.) Then the Team returned to aerosols as the culprit. Handy, because it's difficult to prove.
The moment people start using terms like 'externalities' I know they have something to hide.
"discredit scientists and scientific research on climate change."
Scepticism and criticism of research is equivalent to 'discrediting' researchers. Off to a bad start...
(1)
The graph he cites does not present a clear argument either. What explains the dramatic warming from 1910 to circa 1942 if CO2 has to be ruled out in that case? There are other anomalies in that climate history and it also shows steady warming long before CO2 became a factor after 1950. What caused that? (The reasons are also largely unknown although there is speculation it had to do with increased solar activity.)
(2)
He needs to discuss uncertainty bounds and probabilities here not just pay lip service to them and not explore the implications of his claims. It is not sufficient to hand wave on this. Since the climate models are about 1 sigma outside the model mean that means they only have a 10% chance of being correct at this point in time. You may or may not view that as 'important' however.
The remainder of the argument is circular. The models must be correct because the assumptions of the models fit the temperature trend. But this only true for 1980-1998. They don't fit 1999-2012. And they don't fit any other time periods either, unless rather arbitrary assumptions (fudges?) are included. Not exactly a smoking gun argument.
(3)
This is essentially a logical fallacy known as 'begging the question'. You need to prove your case before you can discuss the consequences. Climatists will generally try to switch as quickly as possible to discussing negative consequences because the task of proving their premises is onerous.
(4)
Climategate emails actually refute this part of his argument, although it substantially more opinion than argument. It has been argued in the literature that in Kunhian style paradigms are actually the norm and not the exception for scientific research, so it's not clear to me what he is attempting to refute here.
(5)
Since the claim is self evidently true, the attempt at a rebuttal here is silly. Drug company researchers don't get to vet their own drugs because of a financial conflict of interest. That financial incentive can colour research is not exactly a controversial claim to make.
(6)
This whole area is largely a question mark and probably should have been left out of the debate by both sides.
Tol and 'negative externality'
Richard, quite aside from the fact that such analyses based on a framework of externalities may yet only be a trendy thing to do, and whose underlying assumptions may not withstand either closer scrutiny or the test of time...
... you method of characterizing a thing as a negative externality can be apparently applied to virtually anything. For instance, I could arbitrarily decree that the island of
How does economics square with characterizing basic biological molecules as 'negative externalities'?
incomplete post above.
I could arbitrarily decree that the island of England and Scotland can only hold X people, and all above it, are a burden, to be dealt with. Or, I could declare that those activities that generate negative externalities to be negative externalities.