Comment on Pielke Jr’s main conclusions

Roger Pielke Jr invites comments “from his loudest critics” on his views regarding climate change and response strategies. I’m not even close to being his loudest critic (e.g. he’s often got interesting analyses on the policy), allthough the occasional badmouthing of scientists gets on my nerve. Anyway, here are my replies, each directly following Pielke’s point in italics.

1. There is no greenhouse gas signal in the economic or human toll record of disasters.(Pielke)
I don’t know; his work in this area appears quite robust at first sight, though many conflicting results have also been reported. The PDI (power dissipation index, a measure of hurricane power) has increased though, at least in the North Atlantic. Overall, the jury is still out on the hurricane question it seems like. It’s however not an area that I’ve looked at in detail.

2. The IPCC has dramatically underestimated the scale of the stabilization challenge. (Pielke)
I don’t know, but see also 8.

3. Geoengineering via stratospheric injection or marine cloud whitening is a bad idea. (Pielke)
At this point in time, intentionally cooling the Earth via large scale intervention is definitely a bad idea, because of the risks involved. But we may reach a point where the climate risks start to outweigh the geoengineering risks. So I think it prudent to investigate geoengineering schemes in case of climate emergencies. I agree with Ken Caldeira: “I hope I never need a parachute, but if my plane is going down in flames, I sure hope I have a parachute handy,” Caldeira said. “I hope we’ll never need geoengineering schemes, but if a climate catastrophe occurs, I sure hope we will have thought through our options carefully.” I contributed to an assessment of “other” climate reduction possibilities, for which I wrote chapter 6 on geo-engineering and air capture. In Section 6.4 the context and associated risks are discussed. In short, geoengineering should absolutely not be considered as an *alternative* to emission reduction, since the long term risks would increase to intolerable levels in such a case, and problems such as ocean acidification would continue unabated. I plan to write more about geoengineering here in the near future. 

4. Air capture research is a very good idea. (Pielke)
Agreed (though it’s not a holy grail; it’s not even close to large scale implementation). I would perhaps single out biochar application as especially promising, since it appears to have numerous co-benefits. Its global scale climate mitigation effects seem to be limited though.

5. Adaptation is very important and not a trade off with mitigation. (Pielke)
Both adaptation and mitigation (emission reduction) are important, but I would emphasize the latter, since it dominates the long-term risk we expose future generations to (CO2 has a very long lifetime). Over-emphasizing the former risks de-emphasizing the latter, so it’s a tricky balance. The four basic response strategies (emission reduction – air capture – geoengineering – adaptation) are not mutually exclusive, but each of them lowers the (perceived) necessity for the other measures to be implemented (if the long lifetime of CO2 is ignored, which is well beyond the average political radarscreen).

Roger claims that ”adaptation is a trade-off with mitigation just as mitigation is a trade off with military spending.” I think that a Euro spent on adaptation competes more strongly with spending it on mitigation than that it competes with spending it on the military. If anything, adaptation and mitigation are decided upon by the same department, with one overall budget. The military budget is separate (unfortunately, I may add).

It may be worthwhile to investigate potential win-win situations: Adaptation measures that simultaneously mitigate climate change, and vice versa (see chapter 4 of the same document as mentioned above for some examples, e.g. green/white roofs, reforestation, spatial planning, etc). Black carbon (soot) reduction is an example of a measure with both health and climate benefits. Those may be the politically speaking low hanging fruit.

6. Current mitigation policies, at national and international levels, are inevitably doomed to fail. (Pielke)
It all comes down to what is being decided in the political process. I am however pessimistic about the politics coming up to speed with what is known scientifically (short version) and what is possible technologically (which is a lot more than what is on the political table, see also 8). But let’s try to avoid self fulfilling prophecies.
David Keith made some pertinent comments to this:

However when people and the political community hear technical people say “can’t be done” they assume we mean that technically can’t be done and that is untrue and destructive.
It’s destructive because it hides the central moral choice: we could cut emissions if we want to, we could have started decades ago when the scientific warnings about climate change were first raised, but we decided not to. It was a choice, implicit or not. A choice that, in effect, we cared more about current consumption than we did about preserving our grandchildren’s chances to enjoy a climate like the one in which our civilization developed.

Nothing is “doomed to fail”; we have the choice.

7. An alternative approach to mitigation from that of the FCCC has better prospects for success. (Pielke)
I don’t know. Depends what the proposed alternative is I guess.

8. Current technologies are not sufficient to reach mitigation goals. (Pielke)
Perhaps that is the case for the long term, but I think it bears stressing that current technologies are hopelessly underused. David Keith, Joe Romm and others have pointed out that even with current technology we could decarbonize the entire electricity production for a few % of GDP. The per capita emissions in the US are double those in the EU. The per capita electricity use in California is a bit over half of that of the rest of the US. There’s clearly a lot more we can do with current technology and other (efficiency) measures than we are currently doing. That doesn’t negate the importance of R&D, but it’s the point I would like to stress. R&D is still needed to make emission reductions cheaper, and to make bigger and faster reductions possible. But it shouldn’t be an excuse for not doing more with the possibilities we currently have. See for a longer argument somewhat along these lines (rebutting Lomborg) here.

9. In their political enthusiasm, some leading scientists have behaved badly. (Pielke)
Without specifics, this is impossible to answer, and is bound to lead to even more misunderstanding. I could try reading your mind of course. You probably have some of your critics in mind, notably some RealClimate scientists as well as Hansen, who you have criticized. I find this very problematic. In most instances that I followed (involving Gavin Schmidt, Michael Tobis, Eric Steig, Hansen, Briffa at different occasions), I have found your and others’ criticisms off base, besides the point, largely irrelevant to the bigger picture and having the smell of a smear campaign (science-bashing). As I commented regarding the latest McIntyre affair (see my review here): “A lot of scientists are getting understandably frustrated with self-proclaimed auditors of science (and their supporters) who cast doubt about a whole scientific field by blowing minor flaws out of proportion and insinuate accusations of scientific misconduct”. Against this backdrop of a lot of people ready to embrace any little nitpicked criticism as if it overthrows the whole scientific consensus, and ignore the mountain of evidence in favour of this consensus, I can perfectly well understand that a lot of scientists (and their supporters) are getting frustrated having to deal with this behavior and (mostly) fake arguments. In the grand scheme of things, the big problem as I see it is the contempt of science and its practitioners by a sizeable segment of the general public and some high profile bloggers; if a scientist responds to faux criticism in a frustrated tone, I find that a minor flaw in comparison. Granted, they (climate scientists) are your subject of study, so you naturally focus on their behaviour, but at the same time, please consider the context in which they operate, as well as the main message they are trying to convey. In light of this, your claim that “bad behavior by the folks at Real Climate does more to hurt the cause for action than the political actions of the skeptics” is preposterous. William Connolley brought up Fred Singer as the most obvious example.

10. Leading scientific assessments have botched major issues (like disasters). (Pielke)
I don’t know.

The bottom line is that I don’t strongly disagree with Pielke Jr on many points, but that I find his choice of ‘problem areas’ to focus on peculiar and often unhelpful in light of the much bigger problems just adjacent to them (e.g. 9, 8, 5). Excluding that context risks giving a false impression of what’s going on, especially to those who are not in the loop and to those wishing to see their pre-conceived notions confirmed.

Global warming survey

Tom Fuller is doing a survey on global warming. He’s writing for the Examiner, with regular commentary about environmental (usually climate change) issues. He’s framing the survey as a search to see where common ground could be found in terms of policy reponses to global warming, which is an interesting and useful goal to pursue. It is explicitly not meant to be a survey of how many people ‘believe’ in AGW. Based on the bulk of comments on his site, it will be skewed to the “skeptical” point of view anyway. But that’s not the point…

Tom Fuller is a self desecribed ‘lukewarmer’. He has grown quite suspicious of climate scientists and their motives, based to a large extent on blogs where scientists are routinely bashed criticized. He’s an honest guy though, and exemplifies the kind of person with whom it’s both useful and possible to search for common ground, despite (sometimes large) differences in viewpoints.

Update: Survey is now closed. Outcome (>3000 respondents, 85% from WUWT) is heavily influenced by “skeptics”, which offers an interesting glimpse in their kitchen. Half is over 55, a quarter is emeritus. What was that about teaching old dogs new tricks? That they’re mostly republican and libertarian is less of a surprise. But some mitigation measures are more supported (or less opposed) than others. Neither cap and trade and carbon tax are supported, which doesn’t make a lot of sense to me; you’re not necessarily paying more for those measures than for straight taxes on some other measures that you could chose from. I don’t see the rationale behind it, but perhaps I’m looking for something that’s not there.

What do we know?

- The direction of the (expected) changes is clear

      – Globe is warming

      – It’s due to us

      – It’s bad news

- Carbon is forever; Aerosols are not

- Uncertainty + Inertia = Danger

That is the short version of what scientists know about climate change.

And a normative statement: 

- Science should inform policy measures. We are used to that regarding human health; we should also get used to it regarding climate change.

Communicating science: finding common ground

In discussions, you can either stress the disagreements and differences, or you can search for common ground. Greg Craven (the high school teacher with the youtube climate hit a few years ago) does the latter very well, see eg this video of his, where he sais:

I point out that my motivations are simply pragmatic, because in my experience, that’s the case for a lot of you, as well, so it’s common ground for us. (…) What I’m concerned about is me and mine, and our lifestyle.

Terrific. That hits home, it hits a nerve, and more importantly, it hits quite a strong nerve especially with those that are not convinced of the urgency of the problem.

Greg has since written a book (“What’s the worst that could happen?”), meant for the layperson to make sense out of the climate debate. I haven’t read it (yet), but judged from his video’s and website, he’s a great communicator with a healthy dose of both humour and common sense.

Simon Donner makes a similar point with respect to addressing religious constituencies. That one is a challenge for me though, I have to admit. More on that in a later post.

Even when two people disagree, they often both make valid points. Most scientists are good at doing science, and are not great storytellers (with, of course, many exceptions). So they naturally resent being told to go and tell a story, especially so when they feel that they’re being (partly) blamed for the public confusion about the issue. On the other hand, Olson is right, that the nature of the game has changed, and that scientists who do communicate to the public better be aware of how the public filters and digests information these days, and shape their message accordingly.

The latter episode is an example of an all too common pattern: When someone’s role is criticized, it invokes a defensive reaction. Whereas more often than not, there are multiple reasons for the problem under consideration. In this case, there are weaknesses in all parts of the chain that hamper the communication and use of climate science: A lack of good communication by scientists, a lack of scientific literacy amongst the public, the education system, the political system, a lack of fact-checking by the media, disinformation by vested interests, etc. And in many of these cases, it’s very hard for individuals to change their behaviour for the better, since the institutions were built in accordance with the status quo. E.g., the way scientific work is structured and valued actually dissuades them from engaging in public outreach.

Web-iquette for climate discussions

When checking some odd stuff regarding taking care of our 3 year old, I came across this web-iquette for discussing your internet search results with the doctor. Many of the same principles apply to a layperson browsing the web about climate change, which inevitably raises questions about what is true and what isn’t. The list bears some resemblance to my effort at providing hints for how to distinguish sense from nonsense in the climate change ‘debate’ (or other complex scientific issues such as health).

Now I’m a bit of an internet-doctor myself, so it’s useful mirror to look into. The list is as follows (replace “doctor” by “scientist” for more climate relevance):

1. Do bring it up. “Most doctors don’t see your research as an attempt to second-guess them.” (as long as you don’t accuse them of being a bunch of frauds, of course)

2. Keep the tone conversational, not confrontational. It sounds so sensible, yet so many people offend this very basic rule of human interaction. Me too, more often than I want to. Tell us that the science is just garbage, and we’ll stop listening to you very quickly. Or we’ll tell you to bugger off, if we’re in a bad mood and forget about this rule ourselves. Usually with a reference to a link or two.

3. When you get a diagnosis, ask the doctor to spell it.
A-n-t-h-r-o-p-o-g-e-n-i-c  G-l-o-b-a-l  W-a-r-m-i-n-g.

4. Check who’s behind the site. ”Falling for information from untrustworthy sources is the biggest mistake parents laypeople make. “Anyone can set up a site called the National Association for Such-and-Such,” pediatrician Alanna Levine notes. Check the “about us” section to see if the information was written or vetted by doctors scientists. Look for sites from government agencies (look for the .gov at the end of the link), universities (look for the .edu ending), or medical scientific organizations such as the American College of Obstetrics and Gynecology IPCC or the American Academy of Pediatrics NOAA, KNMI, etc.”

5. Don’t confuse personal experience with science. Anyone can write anything on the internet. Beware, it’s a dangerous place. And, don’t confuse weather with climate. Please. It’s making us soooooo tired.

6. Don’t assume your doctor has blown it based on what you read. Proclaiming that the science is all garbage just because you know how to use google does not impress anyone. Please refrain from doing so, it just makes you look silly. And if you’re really convinced of yourself, why don’t you submit your ideas to Science or Nature?

7. Let your doctor help you evaluate what you find. “There’s something to be said for a professional (such as a scientist) who has a base of knowledge and can help you sort through your own research,” says pediatrician Joseph Kahn. A doctor scientist can help you determine if the site is trustworthy (…) and if the information you found is outdated.” Expertise matters. You wouldn’t let your accountant do the plumbing and your plumber file your taxes, right?

8. Realize no doctor can read every single study the moment it comes out. “Medicine Science is constantly evolving”. Though that doesn’t usually mean that everything we know today will be invalid tomorrow. The big picture only changes very slowly.  Eat and drink in moderation and varied, and get enough exercise. More greenhouse gases in the air cause more warming. It’s been pretty stable advice/science for a while. Details may shift (is coffee good or bad for you? How important is aerosol nucleation for climate?), but the big picture less so.

9. Definitely ask about what’s confusing or troubling you. Asking, yes. Bringing up doubts, fine. Rational discussion, absolutely. Accusations of fraud, claiming that we just want to steal your SUV, nah.

Btw, it’s Blog Action Day! (with climate change as its theme.) Check out some of the links if you’re interested in more climate related blogs.

Did McIntyre have the data all along?

The bunny is right on top of it. He quotes an excellent comment from ClimateAudit about the fact that McIntyre was being told who to contact about the data. It is written in a very non-judgemental way, but in between the lines the message is clear. I.e. some of McIntyre’s writing tactics are being used to convey the message. Eli calls it a work of art.

Craig Allen over at Deepclimate brings the news that McIntyre was already provided with the data 5 years ago (!), but was unsure that they were the real deal, so he wasn’t ‘immediately’ satisfied. Deepclimate’s post itself details how the Russian scientists (and originators of the data) have an analysis based on a much bigger sample that basically confirms Briffa’s results.

If this wasn’t already a tempest in a teapot, then it most definitely is now.

Update: Tim Lambert (Deltoid) has a round-up as well, with some relevant quotes.

McIntyre’s role in the latest teapot tempest

This whole tempest in a teapot about the Yamal tree rings made me curious about how this story, with an analysis by Steve McIntyre at the centerpoint, gained such traction. The not-so-critical part of the blogosphere ran away with his results, blowing it way out of proportion in their haste to claim that climate science is a big sham. How much credit or blame (dependent on your viewpoint) goes to McIntyre for how this story panned out in the public mind?

Jim Bouldin gives a thoughtful rundown of the major issues.

What struck me was Roger Pielke Jr’s attack of RealClimate’s sarcastic reaction to this sorry story, and his defense of Steve McIntyre, quoting him as follows:

It is not my belief that Briffa crudely cherry picked.

Fair enough, one might think. Except that this quote is from comment number 254 in one of the Climate Audit threads. And it doesn’t particularly square with what he said elsewhere. It is most definitely not the message that his readers got (see for some collections here, here, here and here). One could reasonably argue over how much to blame the readers (as Pielke does) versus how much to blame the author (McIntyre in this case) for any ‘misunderstanding’. But judging from the vast majority of his readers who infer grave accusations from his writings, it’s fair to at least look into the latter as a possibility.

Some other quotes from McIntyre, mostly assembled second hand (a.o. commenters Andrewt, Phil Clarke and Jim Bouldin, my emphasis):

“If you can get a single dendrochronologist to support Briffa’s use of 10 trees in 1990, I’ll be flabbergasted. They will be astonished and appalled at the procedure. The young dendros will be wincing and some of them will probably be bit shell-shocked at this news. It’s very embarrassing for the field.”

“In my opinion, the uniformly high age of the CRU12 relative to the Schweingruber population is suggestive of selection – in this respect, perhaps and even probably by the Russians”

“It is highly possible and even probable that the CRU selection is derived from a prior selection of old trees”

“I do not believe that they constitute a complete population of recent cores. As a result, I believe that the archive is suspect.”

“Because the selection yields such different results from a nearby population sample, there is a compelling prima facie argument that they’ve made biased picks.”

“Unfortunately, to date, people in the field have not honored this responsibility and, to an outside observer, seem to have done no more than pick the version (Yamal) that suits their bias.”

“… the resulting Yamal chronology with its enormous HS [hockeystick] blade was like crack cocaine for paleoclimatologists …”

”…But maybe this is a coincidence. One never knows – it’s climate science …”

“I’d be inclined to remove the data affected by CRU cherrypicking but will leave it in for now.”

Roger Pielke goes on to make an argument that could potentially backfire:

You guys are hilarious. There is no need to pluck out-of-context quotes from deep in comment threads to divine what McIntyre _really_ thinks. He spoke directly to this point as follows:

“I don’t wish to unintentionally feed views that I don’t hold. It is not my belief that Briffa crudely cherry picked. “

Convenienty forgetting that this quote is from comment number 254. He later mentioned that McIntyre, in a more recent headline post, denied having made such allegations:

I did not say or imply that Briffa had “purposely selected” individual cores into the chronology and clearly said otherwise.

It is not clear whether the “otherwise” refers to his comment number 254 or perhaps also to other places. However, it is clear, both from what he wrote elsewhere and what the vast majority of his readers deduced, that he successfully implied strong allegations. He’s hardly ever saying it point blank. He doesn’t need to, since his audience is all too eager to get his message.

Commenter Andrewt calls it dog-whistle politics:

You say one thing, but your choice of words means your target audience infers something quite different.

Making the insinuation subtle enough to be able to defend himself later (‘I made no such accusations’), and clear enough so that the message gets through to his supporters. Which it does: For miles over the internet, people refer to McIntyre as the source of having uncovered this ‘scandal’.

Andrewt sums it up:

Steven McIntyre unambiguously says what Gavin claimed he said. Gavin did not lie.

Steven McIntyre has now added a retraction after this comment.

Will you also add a retraction to this post and an apology to Gavin?

No reply on the latter.

Interestingly, Roger feels he is upholding important scientific standards, whereas I feel that this whole sorry story is about science bashing, which he seems to be endorsing or turning a blind eye to. I do believe, however, that he is sincere in what he thinks. But I also think it’s misplaced. I hold him, as a political scientist who frequently has interesting viewpoints to bear, to higher standards than some other parts of the blogosphere.

To McIntyre’s credit, he has set some of the more fanciful journalists straight in blowing the story out of proportion, as Phil Clarke points out:

While there is much to criticize in the handling of this data by the authors and the journals, the results do not in any way show that “AGW is a fraud” nor that this particular study was a “fraud”.

Perhaps he’s just naïve, that he doesn’t have the foresight how people will interpret his writings? It’s not that it hasn’t happened before though.

I’ll finish with two other memorable quotes from McIntyre, which shows how he levels insinuations at scientists. Or outright disgust.

Is Gavin Schmidt honest?

Try not to puke.

I’ll leave it at that.

Update:

McIntyre’s accusations of stonewalling do not seem to hold water, as Marco points out in the comments. See these quotes from ClimateAudit (2006, here and here, respectively), h/t Marco, dhogaza and Eli Rabet:

“Science (…) suggested that I contact the original authors.”

“Steve these data were produced by Swedish and Russian colleagues – will pass on your message to them
cheers, Keith” [Briffa]

Seems like he’s been barking up the wrong tree, even after it’s been pointed out to him. 

Communicating science: dealing with questions

“…he respectfully treated each question as a genuine search for knowledge.”

(e-skeptic, h/t Hank Roberts)

I think that is the best way to get people to accept the science. It is easy for us who are deeply entrenched in the on-line climate debate to forget how a newcomer perceives the issues. Take the example of Matthew L. at Realclimate’s excellent post on communicating science: My impression is of someone trying to make sense of the daily news stories by browsing the internet, without having a strong opinion about climate change one way or the other. I think he exemplifies the kind of person we need to –and can- convince of the strength of the scientific evidence. We should be thinking carefully about how to best do so. An interesting conversation ensued between Matthew and others, myself included.

I think the tone of the response is important. Even if he were just repeating claims picked up from some anti-scientific website, what would do more good for him and for the numerous people reading (but not participating in) the comments: A sarcastic reply calling him out on his ‘denialist’ talking points or a patient explaining of the issues? And what if he indeed were sincere in his concerns and (perhaps misguided) questions? 

When dealing with the hard-line Morano’s of this world, it may be different. But otherwise, a calm and collected attitude is important. And even with the likes of Morano, it is not clearcut that abusive language is the way to go. Keith Kloor writes:

“If I was stranded on a desert island because of global warming and I had a choice to live out my days with either Morano or Joe Romm, it’s no contest.”

That’s what we should avoid. Perhaps being nice is a better strategy. For Joe Public, it matters a helluva lot who is the nicest guy. They don’t know who is right or who is wrong. Many of them decide based on their gut feeling.

This quote from Matthew is another example of what should be avoided:

“Sad to say JP (a climate activist) did not acquit himself well. He got progressively angrier and ended up shouting, and was even forced to back-track at one point. In contrast the denialist remained very level headed. Anybody listening to the interview and not familiar with either person, or the positions they represented, would have scored a definite win for the denialist camp.”

Hondenpoep, bumperklevers en Wilders

Dat zijn toch wel drie dingen waar ik me het meest aan erger sinds ik weer in Nederland woon (na 10 jaar in het buitenland). Kom ik gisteravond terug van de speeltuin met mijn dochtertje, stinkt later ons hele huis naar hondenpoep! Wie haalt het in zijn hoofd om zijn hond in een speeltuin de behoefte te laten doen, en het dan ook nog eens niet op te ruimen?! Kan Wilders zich daar niet eens over opwinden?

De rode draad bij deze drie dingen: Asociaal gedrag. Net doen alsof de wereld van jou alleen is, en ‘anderen’ moeten zich maar schikken naar jouw onhebbelijkheden.

Het heeft niet direct iets met klimaatverandering te maken (ik moest het alleen even kwijt). Maar indirect misschien wel. Daar speelt asociaal gedrag ook een rol, alleen zijn de ‘anderen’ dan mensen in de toekomst. Het kan geen toeval zijn dat de PVV klimaatverandering ontkent.

Update:

Een debat over klimaatbeleid kabbelt voort. Tot Tweede Kamerlid Diederik Samsom van de PvdA het woord neemt. ,,Iedereen heeft recht op zijn eigen stupiditeit”, zegt hij. Dus kan Samsom nog accepteren dat het klimaatbeleid van de PVV niet veel meer is dan ,,moslims eruit, zeewater erin”. Maar dat de PVV de kans negeert om een betere wereld voor het nageslacht te bouwen, dat moest wel ,,een vergissing” zijn. Zat er een ,,macabere logica” in de kritiek van de PVV op zwemles voor moslima’s?

(NRC, 19 oktober 2009)

Bjorn Lomborg’s eternal postponement

(Nederlandse versie hier)

Lomborg suggests we keep on gambling with the planet’s climate by postponing measures far into the future. Not a good idea.

The problem with CO2 is that a large part of our emissions stays in the atmosphere for centuries or even millennia. On top of that, the climate responds slowly to changes in greenhouse gas concentrations. This combination leads to great risks for the future climate if we don’t curb our emissions soon. This is being consistently ignored by Lomborg’s analyses.

If big changes, such as melting of the great icesheets, are initiated due to elevated concentrations of greenhouse gases, they are not necessarily reversible. The costs of taking measures now is lower than the costs of cleaning up our mess later; that is the conclusion of e.g. McKinsey ( here and here), the Stern review, and the International Energy Agency. The bottom line of these studies is that for about 1% of global GDP the most dramatic consequences of climate change can be prevented. The costs of unlimited global warming are much greater.

Unfortunately risks that only materialize far into the future are underestimated and undervalued by people, with respect to the cost of limiting those risks. Take smoking: For many people, stopping that ‘nice’ habit is too large a price to pay in order to limit future health risks. And it’s addictive of course. Just like our high energy use is, apparently. In contrast to smoking, actively decreasing climate risks is complicated by the ‘tragedy of the commons’, which Lomborg frequently (ab)uses in his argument. Another one of his favorites is to put up a false dilemma.

Let’s indeed look for solutions that keep the consequences of global warming within acceptable limits (and outside of the dikes). A precondition for that is of course that we base ourselves on the scientific insights about the climate system. Lomborg seems to have another view.

(For more background on how Lomborg bends the science, see here)

A few cost estimates:

IEA: The investment required to prevent dangerous climate change is “an average of some 1.1% of global GDP each year from now until 2050. This expenditure reflects a re-direction of economic activity and employment, and not necessarily a reduction of GDP.” In fact, this investment partly pays for itself in reduced energy costs alone (not even counting the pollution reduction benefits)! (via Joe Romm)

Stern: “Using the results from formal economic models, the Review estimates that if we don’t act, the overall costs and risks of climate change will be equivalent to losing at least 5% of global GDP each year, now and forever. If a wider range of risks and impacts is taken into account, the estimates of damage could rise to 20% of GDP or more.
In contrast, the costs of action – reducing greenhouse gas emissions to avoid the worst impacts of climate change – can be limited to around 1% of global GDP each year.”

McKinsey: “The macroeconomic costs of this carbon revolution are likely to be manageable, being in the order of 0.6–1.4 percent of global GDP by 2030. To put this figure in perspective, if one were to view this spending as a form of insurance against potential damage due to climate change, it might be relevant to compare it to global spending on insurance, which was 3.3 percent of GDP in 2005.”