Saturday, May 12, 2012

"absence of evidence is not evidence of absence"

This one deserves a post of its own: James Hansen's truly apocalyptic vision of current climate; the answer by Martin Hoerling from NOAA, and finally Kerry Emanuel's comment  here on Andrew Revkin's dotearth. In my opinion, Kerry Emanuel's statement demonstrates beautifully that both alarmism and its critics have done their job; now it's time to talk seriously.

(Thanks to Reiner, who posted the link to these articles already here).


eduardo said...

Hansen is surely an intelligent person, and he has likely read Revkin's post including Hoerling and Emmanuel comments. Hoerling and Emmanuel represent different stances, but both agree in hat there does not seem to be a definitive evidence. Emmanuel even speaks about 'absence of evidence'. What surprises me is that Hansen doe not seem to understand that he is only preaching to the choir , to those only already convinced, and that at the same time he is putting off all the rest. That strategy, even assuming he is totally convinced that he is correct, leads to no where, and is even damaging to the cause he is trying to support. He is already brought to the media his warnings many times. What is the point of repeating his message over and over again ?

hvw said...

What surprises me is that Hansen doe not seem to understand that he is only preaching to the choir , to those only already convinced, and that at the same time he is putting off all the rest.

I believe that this is not about convincing anyone. I believe Hansen's purpose is to help keeping the topic in the news, with all he has available (status and an idea about agenda-setting-theory). I believe he does this because he feels morally obligated and consciously sacrifices other values such as intellectual honesty.

This strategy obviously works to a certain extent, even though it is very debatable whether it has the desired effect in the long run, or might even backfire.

Werner Krauss said...

@eduardo and hvw

Hansen talks about his view of climate; you talk about strategies. Not sure if everybody talks about the same thing here, necessarily.

Furthermore, if there is no evidence of absence, you cannot proof Hansen wrong.

Strangely enough, I can live with Hansen - as if somebody has to tell this kind of story. I also understand the critique of this story. What I am interested in is:
How does a better story about climate variability and uncertainty (including the possibility of disastrous effects of anthropogenic climate change) look like, and what is a "good strategy"?

Anonymous said...

@ Werner

"How does a better story about climate variability and uncertainty (including the possibility of disastrous effects of anthropogenic climate change) look like, and what is a "good strategy"?"

The "good strategy" is to avoid the kind of games people like Hansen, Emmanuel ("citing a single paper") and others use to play as you can read here ...

Last but not least ...

A better story?

There isn't necessarily a better one just because some scientists, always the same bunch of people by the way, prefer to repeat their bad version.

The "truth"or the "real" plot consists of rather boring papers and results. Nothing really to get excited about, neither in this nor in the opposite direction.

V. Lenzer

hvw said...


They key word here is "story". Hansen most likely believes in what he is saying and there is good reason for that belief. What is "off-putting" is the blatant disregard of scientific integrity, in the sense of

[That] extra type of integrity that is not lying, but bending over backwards to show how you're maybe wrong, that you ought to do when acting as a scientist. And this is our responsibility of scientists, certainly to other scientists, and I think to laymen. (Caltech's 1974 commencement address by Richard Feynman)

In other words, we (and I boldly speak for eduardo here) judge the quality of a scientist's account in a newspaper by how close it relies the message of the latest and best review paper on the subject. Unfortunately, such an account does not necessarily make a "story" for the news media.

If your goal is foster environmental responsibility in US politics, then a "good strategy" likely should include effective use of the news media and in that sense Hansen's story is pretty good. And there is historical evidence that putting out stories like that can be very effective (see Rachel Carson). The trade-off of course is, that in the long-run, stepping down to the level of politicians and PR firms in the interaction with the public may weaken the status of science in society. Now "what is a 'good strategy'?" We are eagerly waiting for results from the social sciences to answer that question.

Anteros said...

One of the problems I occasionally encounter is that when I claim that my scepticism is directed at the likelihood of catastrophe, disaster, apocalypse and the final complete thermogeddon, I'm told repeatedly by the 'climate-concerned' that such things are simply climate-denier strawmen arguments.

This always surprises me (as I'm under the impression that 'Catastrophes' are predicted rather commonly) so I'm hugely grateful to James Hansen for continuing to provide evidence of my contention.

I also agree with Eduardo @1 - I think Hansen is quite sincere (though wrong) but is actually no help at all to his cause. He's probably the climate sceptic/realist's best friend, although I suppose there has to be somebody at the extreme end of the alarmed/un-alarmed spectrum. It's lucky for the un-alarmed that the over the top rhetoric is coming from the head of GISS NASA, no less.

Werner Krauss said...

@ V Lenzer #4

Glad to hear, V Lenzer. If everything is fine at the climate front, we could devote in the future klimazwiebel to the discussion of soccer results (just like R.P.jr). I mean, who could have predicted a 5:2 for the BVB? Contrary to climate, soccer indeed is a bag of surprises!

eduardo said...

Of course, he is entitled to express his opinion whenever he likes to do so. I was trying to see Hansen's perspective and trying to understand his behaviour. He may be writing as a worried scientist, warning society about the risks (or certainties) of climate change. In this is case he would be just repeating his already very well known message, there is nothing new in his article. So I surmise that he is not acting as a scientist here. he is rather writing as an advocate of some sort of action, and in the end of the article he tries to compel his readers of the necessity of change. my comment expressed my opinion that this strategy - as a political advocate - does not seem to be working, already since a long time ago. We saw year 2007 passed with the presentation of the three parts Fourth Assessment report together with the Summary for Policy Makers and every time opening the evening News. Did it work, from Hansen's perspective ? what can he possibly add ? I dont think so. Probably he explains this away by the covert action of Big Oil. I would rather think that Big Oil would be more than happy to fund Hansen as well.
I do not know what would be - still from Hansen's perspective- the right strategy , but it does not seem to be very smart to flog a dead horse all over again. Even Emmanuel does not feel very confortable trying to defend Hansen. Maybe I am too blind, and he is just keeping Obama's voters' mood high until November

Anonymous said...

Good example, Werner.
Hansen chose to be player, not arbiter. If there's a hard playing skeptic team, we can't fight with a team of arbiters against them. But right, maybe Hansen committed a couple of subtle fouls, but not hard enough for penalties.


Anonymous said...


So I surmise that he is not acting as a scientist here. he is rather writing as an advocate of some sort of action,...

Right, he is fighting against the XXL-pipeline.

But remember: In 1988 Hansen spoke in a congressional hearing about global warming and its consequences. He had no proofs at that time, today we know he was right. Who knows, maybe we will see in a couple of decades that Hansen is right again?



Reiner Grundmann said...

I think Eduardo is spot on. After all, we did have an alarmist drive from 2007-2009 but it did not work. This is the old script which is based on the assumption that more and more people need to be convinced of the climate gospel. That people need to follow enlightened, selfish scientists like Hansen. If this did not work during the period of the high tide, it is doomed when the ebb sets in. The problem is that scientists like Hansen do not reflect about these social and political parameters. Their natural response is based on a scientistic ideology.

But even within this ideology, Hansen makes some extremely questionable statements (such as the Russian heatwave being proof of dangerous global warming).

Werner, you ask: what would be a better strategy that allows for disastrous effect. My answer is: admit and describe the uncertainties. Do not pretend that the lay public (or the sceptics) cannot grasp these essentials.

Anonymous said...

@ Werner Krauss

"Contrary to climate, soccer indeed is a bag of surprises!"

You should know better. Climate IS A BAG OF SURPRISES indeed, while predicting the BVB to win against Bayern is probably the easiest way to earn money - if you are betting.

Reiner Grundmann puts things clearly ...

"admit and describe the uncertainties. Do not pretend that the lay public (or the sceptics) cannot grasp these essentials"

And there IS a huge amount of uncertainties - as compared to actual power constellations in german soccer.

V. Lenzer

Werner Krauss said...

So here we are back again where we started: "to admit and to describe the uncertainties." If you have a look back at my original post and click on the Revkin link, you will find Kerry Emanuel's statement on Hansen's op-ed piece. Emanuel says that we simply don't know if those extreme weather events like the Russian heat wave have something to do with climate change. This is what uncertainty means. We don't know the truth. Uncertainty also means that it is certain that "the absence of evidence is not the evidence of absence".

While we may cry some tears about the misuse of science (and Hansen indeed misuses it), from now on we cannot hide any longer behind the strong shoulders of science when we discuss Hansen. Because science cannot proof Hansen wrong when he talks about the Russian heatwave, the tar sands or renewable energies.

It will be a great challenge to sing the gospel of uncertainty. It means to lay down our strongest argument, science. For Hansen, this is nothing new. He publishes his argument as on op-ed piece on the opinion page of the New York Times.

Werner Krauss said...

@Reiner #11

Are you sure that Hansen's strategy failed? As far as I know, Obama suspended the import of tar sands (correct me if I am wrong).
I think we have to judge differently: in my opinion, Hansen puts his bets on social movements and civic protest. Others put their bets on administrative measures on the level of governments etc. These strategies are often incompatible and even contradictory, but not mutually exclusive.

(Once, Germany's Green party supported protest against themselves in Gorleben - they were both government and against it. It didn't hurt their credibility.)

Furthermore, Hansen (I should write: the Hansens) was incredibly successful in keeping the topic of climate change in public discussion. The gospel of uncertainty will only be heard because of - and not despite - "the Hansens".

We should acknowledge this. This does not mean that we have to support his "scientistic ideology" - as said before, of course we have to abandon any "scienticism" (does this word exist?).

Anonymous said...

@ Krauss

"the gospel of uncertainty"

Nice metaphor. In gospel or spiritual music there is a “call and response”system, lead singers (moaning or groaning) and an answering chorus,

In a call and response chant the preacher or the lead voice sings a verse and the chorus answers.

In climate science the chorus used to answer "consensus" for (too) many years and on (too) many calls.

If these days a growing number of the chorus singers replies "uncertain" instead of "consensus", there is no harm for the music itself.
You are just witnessing a deconsecration of the religious belief in the lyrics ...

V. Lenzer

Werner Krauss said...

@V Lenzer

Sure, no harm for science; science easily can deal with uncertainties.

The harm is for science as an argument in political debates. It cannot decide specific controversies (and it creates permanently new ones).

Reiner Grundmann said...

the measure for success can only be a working climate treaty, not the plugging of single fossil fuel sources. But Hansen realizes that such a treaty is off for now and thus he develops a politics of despair. In similar fashion we could say every car which is left unused for a day is a victory for the climate...
And I doubt Hansen wants to address social movements - maybe a projection on your part?

Re. Russian heatwave: available evidence shows that his claim is unsupported.

Finally, dealing with uncertainty is nothing new for decision makers. Perhaps it is for scientists. And for all those who believe that the involvement of climate SCIENCE makes the issue less uncertain.

Anonymous said...


"Re. Russian heatwave: available evidence shows that his claim is unsupported."

Really? Take a look at this collection of papers:

Or let's see, what the honest broker Kerry Emanuel says:
I see overstatements on all sides. Extreme weather begets extreme views. On the Russian heat wave, Marty is citing a single paper that claims it had nothing to do with climate change, but there are other papers that purport to demonstrate that events of that magnitude are now three times more likely than before the industrial era.

Like with your hockeystick statements, I sometimes wonder where you get your informations.


hvw said...


In this collection of papers only one claims that the Russian heatwave would likely not have occurred without climate change. And that one is total c ... b ... ok, I can't say what it is within the rules of courtesy of this blog. Lets say the authors use terms such as "probability" in a rather casual manner .....

What is your purpose of making a statement and supposedly backing it up with a large number of links which mostly are unrelated to the statement and which you have not read by yourself? (correct me and accept apologies if you have indeed read and understood these 6 or 7 articles; but just from scanning the abstracts it is clear that you haven't scanned them). So far I have identified exactly this childish tactic only with the pseudo-scientifically arguing denier fraction when they have lost the argument already ...

Anonymous said...

@ hvw

I've counted three papers: Sedlacek et al., Rahmstorf, Barriopedro et al.
The other papers examine the conditions which led to the Russian heat wave, but none of these claims that this event would have occured in similar extent without global warming.

Please be fair:
I've made no assertion that I have proofs that global warming caused the Russian heat wave. All I want to say is that Reiners claim

"Re. Russian heatwave: available evidence shows that his claim is unsupported."

is wrong. There is evidence, the only question is, if Hansen's assessment "likely" is supported.


Werner Krauss said...


interesting statement, but you forgot to add some arguments to support it. Reading it as it is, it sounds simply judgmental (treaty yes, tar sand boycott no), cynical (unused cars), and contradictory (evidence for unsupported claim vs. climate SCIENCE cannot make the issue less certain).

So please elaborate to help me understand your argument! Thanks.

hvw said...


I apologize for the tone of the last post. You kind of got it because you happened to have written the 3rd or so post in a row I read, that tried to make a point by just slinging links to an unwieldy amount of text and expecting the reader to search for the argument's support for himself. Come to think of it, that can be considered Cargo Scientific behavior, typically by people who try to emulate "scientific text" without getting the meaning behind the form. I don't mean you here.

Maybe I did not assign the same meaning to Reiner's quote. I interpreted "Re. Russian heatwave: available evidence shows that his claim is unsupported." to mean:
"There is no evidence for the claim that
We can say with high confidence that the recent heat waves in Texas and Russia, and the one in Europe in 2003, which killed tens of thousands, were not natural events — they were caused by human-induced climate change.

Hansen makes a statement of attribution, implies that this heat wave would not have happened without global warming and further implies that the occurrence of this event is evidence for AGW happening. If you disregard the funny paper, Reiner's statement is correct: The other papers you refer to predict a possibly larger probability of such events happening in the future by assuming AGW a priori (by applying the models which output AGW). For us, who believe in AGW for the right reasons, which don't include the occurrence of a couple of extreme events in the recent past, this is just sloppy and annoying tabloid style. For the AGW deniers, this is like the big juicy uber-strawman handed on a silver platter.

Reiner Grundmann said...

sorry if the comment was not clear. In my view Hansen is a prime example for the old script of climate alarmism which we usually see before important political meetings. So the timing is not surprising as a new round of climate talks begins just now.

Given this context (which I assume to be important, but of course could be wrong) the hope for progress in these talks informs the strategy. I think it is far fetched to attribute Obama's (for now) resistance to tar sands to Hansen's interventions.

This is why I am not convinced that is strategy can be seen as successful. The world's energy demand will be fuelled one way or the other. Tar sands are one thing, promoted by 'irresponsible' Canadians. But what about increasing use of coal in Germany?

I had the impression you thought plugging these fossil sources was a worthwhile strategy. Am I wrong?

To be clear: we should be leaving the stuff in the ground. But we can only do so if we have alternatives.

invest in bamboo said...

The issue with having some debates is fine, no problem for the discipline of science. However, once the whole thing becomes caught up in politics, that is where the stupidity begins.

Anonymous said...

@ hvw

Ok, if you and Reiner meant "with high confidence" as unsupported, then I agree. You are right, I understood Reiner in a different way, but I confess that your interpretation seems to be the right one.

The situation resembles the discussion in the 90s of the last century, when scientists were discussing if they had detected the global warming signal in the noise of natural variability.
Nowadays they discuss, if they could detect changing weather patterns caused by global warming in the noise.

Hansen predicted the global warming signal early in the 80s, and we know today he was right. I would not be surprised, if Hansen's prediction about changing weather patterns will come true in 10 or 20 years, too.

But maybe I'm biased. I'm very fond of a couple of papers by Hansen and his book "Storms of my Grandchildren". If Reiner had read it, perhaps he wouldn't have described Hansen as a "selfish scientist".

Unfortunately we have missed the central point of Hansen's NYT article:

If we burn all oil, gas and further coal, we have good chances to face a dangerous climate change, whatever dangerous will mean. And I agree with Hansen, that it's useless to let the own car stand still or to demonstrate against new coal power plants in NRW. The saved fuels will be burnt in other places. It's more effective to put some pressure on coal mines, tar sands producers etc and btw some pressure on Obama.


hvw said...


"Hansen predicted the global warming signal early in the 80s, and we know today he was right. I would not be surprised, if Hansen's prediction about changing weather patterns will come true in 10 or 20 years, too."

I do not believe in prophets. But I do believe that essentially linear processes are much better predictable than chaotic ones.

Reiner Grundmann said...


I meant "selfless" not "selfish" - sorry for the confusion.

I know should re-read the drafts before hitting the Publish button, but somehow the formatting has changed, so text is spreading out in one line per paragraph. Not sure if this is a Blogger issue.

Reiner Grundmann said...

Hansen's line on global warming and weather extremes has not changed very much since 1988. In 1998 during a public debate with Pat Michaels he said:

"In 1988, and 1989, in testifying to the US Senate, I asserted that number one, the world was in a period of real long-term global warming. Number two, the warming was probably due at least in part to human-made greenhouse gases. Number three, in our climate simulations, global warming was accompanied by increasing climate extremes ... An increase in both droughts and forest Žfires, on the one hand, and heavy rain and floods, on the other."

On this occasion Hansen also mentioned his use of the "loaded dice" as a rhetorical strategy. This allowed him to combine the assertion that "global warming is here" with the statement that only the future will provide the proof. The dice are loaded in such a way that extreme events will be more frequent. Hence the use of the word "likely".

I agree with Werner that Hansen (together with other advocates) was incredibly successful of influencing public perception in such a way (for better or worse). The perception is that climate catastrophe is underway.

Anonymous said...

@ Reiner

I beg your pardon for misinterpreting you. Next time I will read twice.


hvw said...


"I agree with Werner that Hansen (together with other advocates) was incredibly successful of influencing public perception in such a way (for better or worse)."

So do you also agree with Werner in that the "Hansens" were "incredibly successful in keeping the topic of climate change in public discussion"? If so, wouldn't that be a necessary precondition for any political action to happen? If this is so, what exactly was the reason to not endorse "the old script"?

eduardo said...

@ 30
One argument is the following: The claim that the Russian heat wave is (partially) caused by anthropogenic emissions is disputed, and actually it is very difficult to prove right or wrong. A proof must necessarily be based on model results, since it is a counterfactual claim (it would not have occurred, ceteris paribus, in the absence of anthropogenic emissions). This claim may therefore turn in the future to be more supported or less supported by observations. If they become less common, the 'skeptical side' will undoubtedly argue that that claim was another example of unjustified alarmism. We see this already with Atlantic hurricanes: claims in the mid 2000's that they were linked to global warming 'somehow' were everywhere to be seen. Now even model results indicate that the total number of hurricanes would tend to decrease in a warmer world (although they predict an increase in number of the most intense). We see a lull in hurricane activity in the last decade.
All in all, to use Atlantic hurricanes as an argument of action to reduce emissions - being as it was wobbly at that time- has backlashed, and I am afraid something similar could happen to the heat waves, droughts, etc.

Thus Hansen should be very careful with what and how he writes. If he is not 100% sure, and nobody can really be, the way he presents those claims is in the end counterproductive.

Reiner Grundmann said...

Andy Revkin has more on the Hansen story here.

Anonymous said...

„now it's time to talk seriously“

Another nice stage play at Klimazwiebel ...

Eduardo truly understands his role as an honest broker (see post N° 31). Remarkable.

Grundmann trusts in democratical decisions: "admit and describe the uncertainties. Do not pretend that the lay public (or the sceptics) cannot grasp these essentials"

But Werner is not going to be satisfied, stating that “The harm is for science as an argument in political debates. It cannot decide specific controversies (and it creates permanently new ones).“

There are two problems crossing. Politicians and even more administrations got used to call for scientific papers to support their beliefs, concerns, expanding their activites and fields of authority etc.

Common business in the last two or three decades. It did some harm to science but without exaggerations, at least in most of the cases.

Apparently some people turned the key the other way round, looking for a political answer to a scientific problem (the impact of human GHG emissions on the atmosphere).

Clever idea. But if the reputation of science didn’t suffer that much with the „common business“ (see above) it got really damaged by the second approach.

What to do?

„Get back to whre you once belonged“ the Beatles are singing. But how to get back, now that the whole thing has grown to a billion dollar industry?
How to get the genie back in the bottle?

By modesty maybe.

Louisa May Alcott: „Conceit spoils the finest genius. There is not much danger that real talent or goodness will be overlooked long; even if it is, the consciousness of possessing and using it well should satisfy one, and the great charm of all power is modesty“

V. Lenzer

Werner Krauss said...

In my post for this thread, I already provided the links to Martin Hoerling and Kerry Emanuel, who both are critical of Hansen. So why endlessly repeat their arguments in only minimal variation? It's all in the media already, there is nothing left to debunk or to reveal. Not even the skeptical position can claim victimization - Andrew Revkin presents them all.

For me, the really alarming problem is the stagnation of the critical approach. After many years of critique of alarmism, Hansen is easy prey. But the endless repetition of the counter arguments doesn't make the critique any better or stronger; quite the contrary, it becomes a puppet on the alarmist string because it forgets to offer an own idea how to deal with a changing climate. (Only Reiner made here an attempt to contrast Hansen's alarmism with another strategy).

What I find amazing is that nobody seems to be interested in Kerry Emanuel's statement, that there is obviously a psychological need to explain extreme weather events:

"Our Puritan forebears ascribed them to sin, while in the 80’s is was fashionable to blame unusual weather on El Niño. Global warming is the latest whipping boy."

Now it is, of course, easy to ridicule those guys who use climate change as the latest whipping boy; but Kerry Emanuel has one last argument which makes it a little more difficult to rest on this comfortable self-righteous position: he reminds us, that we simply don't know if the recent weather uptick has something to do with climate change: "The truth is that we do not know whether it did or did not; absence of evidence is not evidence of absence."

Now we are all in one boat, including the scientist.

A shortcoming of the critical climate attitude is its reduction to the scientific aspect of the problem; the interesting question is not if Hansen's assertions are right or wrong - the problem of uncertainty does not disappear in doing so, nor do the heat-waves, the droughts and the tar sands.

That's why we need hermeneutics (the reading and interpretation of the signs) as much as falsification and evidence in order to judge a text like the one by Hansen. When doing so, we will maybe find out that uncertainty is pretty alarming, too. It means to take responsibility without being able to rely on the crutch of scientific evidence. We have to find strategies which are based on other evidences, such as cultural values, ethics, and even religious attitudes towards the world we inhabit. That's why those guys who take their bike instead of driving their car in order "to save the climate" are no less ridiculous than the skeptical scientist who can prove Hansen's assertion about the Russian heatwave wrong. More often than not, it's one and the same guy, by the way.

Werner Krauss said...

add: in the second last paragraph it should read:

"the interesting question is not ONLY if Hansen's assertions are right or wrong - the problem of uncertainty does not disappear in ASKING so".

Werner Krauss said...

V Lenzer,

that's how we spend our evenings! Appreciate your theater review; only this one is too much to think for me:

"Apparently some people turned the key the other way round, looking for a political answer to a scientific problem (the impact of human GHG emissions on the atmosphere)."

Could you explain, please?

Anonymous said...

@ Krauss

"this one is too much to think for me:"

Is it really? Try harder.

There is no political answer to a scientific problem in terms of a scientific solution.

People like Hansen call for a decisive authority that doesn't exist in science. It will end up in a call for democratic majorities in the best case - but rather in a call for dogmatism, action and terror.

Besides of climate warming during the 20th century, we have also observed some dogmatic errors the same period. Experiences that should prevent us from repeating at least the worst mistakes. Science and truth were not winning in these dark times, quite the contrary.

Citing myself: "Das ganze System lässt weiterhin Anzeichen einer Autoimmunerkrankung erkennen, indem durch negative Selektion "skeptisches Gewebe" - an sich von unverzichtbarer organischer (wissenschaftlicher) Bedeutung -kurzerhand abgestossen wird"

Too much to think about?

V. Lenzer

eduardo said...


isnt your argument actually what we are all thinking ? that the 'climate problem' is not only a climatological problem ? It is Hansen who is reducing the whole question to just science: 'the science is clear' is his favourite assertion, and continues with ' do what I say'.

when trying to move through uncertainty, unknown costs, unknown benefits, risks, etc, science is only part of the equation. Within pure science, there is one answer to each question, whereas within the climate problem there are many possible answers. We see it every day in economics, which it is also a science. However, its application to real problems is not just an automatic translation of economic theories. In this sense, there are a few similarities between the Bundesbank, Krugman and Hansen. For all of them the science is clear

hvw said...

eduardo and Reiner,

thanks eduardo. I agree on the unacceptable error in Hansen's text. I have written something similar about it above, including mentioning the undesired effect of "fodder for the 'skeptics'".

But that was not my question. There are certainly other "alarmist" texts without such blatant mistakes. Imagine Hansen had replaced that one sentence about the Russian heat wave something such as

"If we don't act now, such catastrophic events will occur regularly in the future and kill an estimated X thousand of cute little children (your grandchildren!) per decade."

That would be acceptable, from the science side, but Reiner would still classify this text as "alarmist old script". At the same time Reiner admits that such headlines help to put climate change on the agenda and keep it there; a necessary condition to make any political action possible in the first place.

So my question still stands: What is wrong with the "alarmist old script"?

There must be a good answer, or else I have to carve the next notch into my keyboard -- for another unfounded paradigm shot down.

Anonymous said...

There is an interesting comment on Revkin's article by R. Pielke Sr.


"Human caused changes in heat waves resulting from the addition of CO2 into the atmosphere have not been shown using real world observational data.

Kerry’s statement that the

'absence of evidence is not evidence of absence'

is embodying a fallacy where from the Merriam-Webster Dictionary

'it’s fallacious to say that something must exist because science hasn’t proven its nonexistence'

Kerry and Andy are misleading readers when they make the statement that “absence of evidence is not evidence of absence.”

V. Lenzer

Anonymous said...

This one is worth reading too ...

V. Lenzer

Reiner Grundmann said...


There is a difference between agenda setting and alarmism. Hansen was successful of alerting policy makers back in 1988. After that, IPCC related activities have largely taken over (mixing agenda setting with alarmism), and Al Gore has emerged as the most influential alarmist.

So it is one thing to say we are potentially facing a serious problem (agenda setting) and another to say we are all doomed if we do not act now (alarmism).

Part of the old script is a heavy dose of climate determinism. Your example fits into this ("your grandchildren will die because of climate change"). Actually, the old script is more sophisticated: it says that the poor countries will be hit harder - this leads to mass emigration, which leads to an influx of refugees into the rich countries. It is this play on immigration fears where climate determinism becomes politically pernicious.

But this is nonsense. Looking at time scales and impacts of climate change adaptation will be needed, no matter if we can prove that weather extremes are natural or anthropogenic.

A final point about the flaw of the old script is the built-in over-selling. It is inherent because the issue competes against other newsworthy issues. More and more drama is needed, otherwise the story is dead for the mass media. This inherent dynamic was enhanced through a zealous desire to defeat the sceptics. Such motivation led to ever more media presence of alarmist climate scientists.

I said that Hansen was successful “for better or worse”. I used to think that this alarmism was beneficial but changed my mind (ca 2007). It is damaging both from a science and policy view: hyping an issue without good evidence will undermine scientific credibility. And if the public are told that it is getting too late to save the planet, they will become apathetic or ignore the warnings.

Above all, decarbonizing our energy and transportation systems is a challenge for society, and climate science (alarmist or not) has virtually no place in this search for solutions.

Werner Krauss said...

@V Lenzer #37

thanks for being so open.

@ V Lenzer #40

good point, except Emanuel and Revkin do not draw the conclusion that something must exist because.... They talk about uncertainty, that's all.

Werner Krauss said...


I like this one:

"In this sense, there are a few similarities between the Bundesbank, Krugman and Hansen. For all of them the science is clear."

I never intended to defend Hansen, far from that. But I acknowledge that Greece is still in trouble, even when the Krugmans (Hansens) get the science wrong, misuse science or underestimate the complexity of the case.

The Krugmans and the Hansens open the door to discuss cases which are too complex to fit in any existing categories. They do so in bending and stretching reality. Serious talk starts from criticizing their short-comings, but shouldn't stop there. In the end, Greece is the problem, not the Krugmänner.

Reiner demonstrates this beautifully in his comment #42.

eduardo said...


there is a snag in this argumentation. There is a difference between widening the discussion, suggesting new solutions , criticizing the old ones, etc, and what Hansen and Krugman do, which is predict Armageddon, being absolutely sure that they are correct. Even more, those who dare to critize them are either denialists or simply stupid. This is not a free lunch - Krugman as economist should know this: every time you issue a prediction that fails to come to pass, or every time you express your conviction about something that everyone else knows is uncertain, nuanced or multifaceted, you lose credibility. This is already happening to Krugman. To Hansen it happened already long ti me ago, so hat they lose their ability to participate in those debates and to influence their public opinion.

Maybe it is not happening yet in the German press reports, but the Spanish media are already collecting all the instances in which Krugman was wrong or exaggerated. Some are even suggesting that actually he is not an expert in finance, which is true (his Nobel prize was awarded for his works on trade and consumer preference). Thus is power of conviction about the problems he is trying to solve diminished and he himself becomes part of the problem.

Who can Hansen have still some influence on ? only on those that are as dogmatic as himself and in this sense he is lost for the climate debate

hvw said...


[This post in 2 parts because of 4096 character limitation]

thank you very much for the extensive answer. In particular your explanations about what "the old script" means, are quite valuable to me. This seems to be almost a technical term, here on Klimazwiebel, but the glossary is lacking. Isn't it remarkable how you get instantly drowned in secondary and tertiary analysis if you are remotely interested in the Hockey Stick, in contrast to the drought you face if you are looking for analyses or just taxonomy of the attitudes, points of view, and current front-lines in the climate debate?

The blog as a discussion platform seems to foster polarization -- and value laden labels to distinguish "us" (honest brokerists, skeptics, postnormalists, ...) from "them" ("normal" climate scientists, old-script alarmists, ...) and entrench a sterile politics-style two-cluster configuration, where the two sides spend all their time & energy in arguing not even anymore about who is "right", but about who has the moral high ground. This leads nowhere. Nobody profits from knowing how you or I judge the "scientific conduct" of Jones, Mann et al. (or the character of Singer, Michaels and Curry) and that we differ big time. Yet, these types of exchanges dominate the medium.

I am happy about your reply because it allows one to question front-lines of the debate and try out new ones. And it reminds me how multidimensional the issue really is.

[climate determinism]
I enjoyed reading J. Diamond's GG&S and I am still digesting an excellent 36 pages piece by Hulme on the subject. Your old-script summary: (1) "the poor countries will be hit harder". I have no doubt that this is true. (2) "this leads to mass emigration". This is pure speculation. (3) "which leads to an influx of refugees into the rich countries". Even more speculation with an extremely revolting subtext, playing on xenophobic fears. This chain is a nice example how the climate issue is (mis)used by all kinds of groups. In any case, the proper answer to (1) is "So what? They are hit hard already, since centuries." And now you, manager of a 3 letter German International development aid organiZation, which has failed consistently for 50 years, asks me for more money because you additionally have to fix all those climate change related problems in Afrika?? In your face! And you, racist politician, who wants to fit out FRONTEX for the coming storm of climate refugees in the future, but really just wants to reduce wrong color of skin migration by the bullet-technique now?? ... You see, Reiner, I can get quite emotional about some "old-script" utilization. But this all comes from entities which are not involved in the climate debate as such, and just use it for their own little goals.

"...Looking at time scales and impacts of climate change adaptation will be needed,.."
I totally agree, although this paragraph occurs to me as a non-sequitur. I might miss some sort of front-line, namely "adaption" vs. "mitigation". I frequently have the impression that people implicitly construct a schism here to strengthen the cozy two-cluster setup. I find this ridiculous.

... continued ....

hvw said...

@Reiner, continued

[alarmism, over-selling & agenda setting]
I agree that a spiral of "more and more drama" does stop working quickly. I believe you that there has been (maybe still is, by a few individuals) a strategy to "convince" the public of the urgency of the issue using this brute force approach, which has to fail (has failed) for the reasons you mention. But I see another side here: It is desirable to have a public awareness and debate, to have political parties designing and refining their positions, to have climate change on the agenda. Therefore the topic needs to be in the news regularly. This can happen from many vintage points, and climate science is just one, but apparently nobody else cares to do this unpaid, un-fun, and dangerous work. Where, for example, are the social scientists who care trying to communicate to the public (that funds them) their findings in the general media? I agree that the balance between scientific correctness and honesty on the one hand, and the requirement for simplification and a certain "uumph" to make the news on the other hand is a difficult and dangerous one. As said before I agree that Hansen here overstepped the border, but: If I take into consideration the type of publication and what I know about the background of the authors, and compare Hansen's NYT article and Grundamnn's recent ST&HV piece with respect to "uselessness due to bias introduced by unreflected identification with one of the stupid clusters mentioned above" --- it's a tie.

["..decarbonizing our energy and transportation systems is a challenge for society, and climate science (alarmist or not) has virtually no place in this search for solutions."..]

Climate science's contribution is a very small yet important one: Estimate time-scales of expected changes under different emission scenarios. Just we did this already; the updates don't change very much anymore. So in that sense, climate science's role in the mitigation domain is over (except geoengineering studies). However, climate science (in transdisciplinary concert with all geosciences) is pivotal (and still has LOTS of work to do) to inform political decisions about adaption strategies. That is also where the action is with respect to the policy-science interface.

Werner Krauss said...


you are right, and the similarities between Hansen's climate and Krugman's economist discourses are striking; they use even the same metaphors; here another example: "The Kings of Denial" on Krugman's blog:

And recently, it was predicting European Armageddon / apocalypse.
But we have to take into account that we deal here with opinions on the op ed page of the NYT, and, as we learned recently from Reiner, the American style of debate is polarizing. Thus, we have to see those martial rhetorics not at face value, but as rhetorical means to mark a position. And this is what Krugman does: he takes a clear stance anti-Merkel and pro-Keynes.

I think it is completely impossible to find out how much influence he has. No doubt, he sits at one of the most privileged and most influential places journalism can offer. Whatever one thinks about his opinion; he explained the financial crisis for many educated citizens, who normally don't understand economies very well.
Maybe you are right he will become irrelevant - economy and the future of the EU(ro) will tell.

Freddy Schenk said...

Krugmann fordert Austritt Griechenlands aus dem Euro. Zumindest in dem kurzen Artikel machen seine Argumente keinen Sinn - die EZB kann Italien und Spanien nur retten, wenn Griechenland weg ist? Andere behaupten ja das Gegenteil – von wegen, wer kommt als nächstes dran?

Das Thema greift heute Tilo Sarrazin in der Talkshow Günter Jauchs anlässlich seines neuen Buches auf - vermutlich wieder aus absurden (nationalistischen?) Blickwinkeln... (ARD, 21:45h). Diesmal nicht "Deutschland schafft sich ab", sondern wie schafft man den Euro ab. Ist das der Gegenentwurf zu einem Krugmann - zumindest seine Bücher verkaufen sich bestens - auch hier werden einfache Gewissheiten verkauft und Fakten/Statistiken als Belege angeführt, wenn sie denn passen. In Foren bekommt man den Eindruck, dass Tilo Sarrazin ein "honest broker" ist im Gegensatz zu Politikern und Ökonomen. WZBW – was zu bezweifeln wäre.

Reiner Grundmann said...

Krugman posed the alternative of deficit spending v austerity. Wrong says Jeffrey Sachs who writes in the FT (paywalled, hence some quotes below).

Here is his background analysis:

"The 2008 financial crisis in Europe and the US arose from excessive bank lending during the 2000s caused by deregulation and excess liquidity from the Federal Reserve and the European Central Bank. The excess liquidity found its way to a variety of sub-prime borrowers. There was a housing bubble in the US, UK, Ireland and Spain; a corporate-acquisitions bubble in Iceland; and a public sector spending binge in Greece.
When the easy credit stopped in 2008, the banking sector was over-leveraged and under-capitalised. Bank assets – including mortgage-backed securities, corporate acquisitions, and government bonds – were heavily impaired, so that bank capital plummeted. A financial panic ensued after the Lehman collapse, with banks ceasing to lend to one another or to blue-chip companies. Liquidity dried up. The US and Europe plunged into a very steep downturn."

Sachs thinks that the immediate threat is a run on the banks, not only in Greece.

"The bank panic is Greece is now accelerating, and could easily push Greece out of the Eurozone unless decisive actions are taken to prevent a massive run on the Greek banks. If such a run occurs, and drives Greece to leave the euro, Greece’s exit would most likely create an even greater calamity, as Portugal, Spain and perhaps Italy, suffer rapid withdrawals of bank deposits as well."

"The eurozone has one last chance. Here are the key steps. Re-establish working capital in the weak economies; re-capitalize the banks, using ample public funds as needed; insist that the ECB be a more vigorous lender of last resort for the banking sector. In short, Europe must fight the ongoing banking collapse with the resolve needed to save Europe from a self-inflicted collapse. Credible fiscal policies and increased investments in human capital and infrastructure are surely part of long-term recovery, but the fiscal crisis can be addressed only after Europe’s tottering banking sector has been rescued."

I wonder what Occupy & Blockupy activists would say to this? Is another bailout of banks a taboo? It should depend on the answer to the question if Sachs' analysis is convincing or not.

EliRabett said...

Hansen had good reason for claiming that the possibility of heat waves has increased significantly