Posts Tagged ‘climate skeptics’

Is Climate Science falsifiable?

February 17, 2014

Guest post by Hans Custers. Nederlandse versie hier.

A very, ehhrmm… interesting piece on
Variable Variability, Victor Venema’s blog: Interesting what the interesting Judith Curry finds interesting. And I don’t mean interesting in a rhetoric, suggestive way; I mean it is a well-written and well-reasoned article, worth reading.

Victor writes about the meme regularly used by the anti climate science campaign, often supported by some straw man arguments, that the science of human impacts on climate would not be falsifiable. He shows it’s nonsense, by giving some examples of how it could be falsified. Or, more likely, already would have been falsified, if the science would be wrong. Victor’s post inspired me to think of more options to falsify generally accepted viewpoints in climate science. If there are any ‘climate change skeptics’ who want to contribute to real science, they might see this as a challenge. Maybe they can come up with a research proposal, based on one of the options for falsification. Like proper scientists would do.

First, a few more things about falsifiability in general. Bart wrote a concise post about the subject four years ago, explaining that a bird in the sky does not disprove gravity. What looks like a refutation at first, might on second thoughts be based on partial or total misunderstanding of the hypothesis. Natural climate forcings and variations do not exclude human impacts. Therefore, the existence of these natural factors in itself, cannot falsify anthropogenic climate change. A real skeptic is cautious about both scientific evidence and refutations. ‘Climate change skeptics’ like to mention the single black swan, that disproves the hypothesis that all swans are white. Of course that is true, unless that single black swan appears to be found near some oil spill.

Some of the falsifications that I mention later on might be somewhat cheap, or far-fetched. It is not very easy to find options to falsify the science of human impacts on climate. Not because climate scientists don’t respect philosophical principles of science, but simply because there’s such a huge amount of evidence. There are not a lot of findings that would disprove all the evidence at once. A scientific revolution of this magnitude only happens very rarely. Whoever thinks differently, doesn’t understand how science works. (more…)

How science does and does not work (and how skeptics mostly fall in the latter category)

June 22, 2011

Another kick-ass article on The Conversation, providing some insights into the scientific process and the place that pseudo-skepticism takes in (or rather outside of) that process.

In science, to actually contribute at the forefront of a field one has to earn credibility, not demand it. Being taken seriously is a privilege, not a right.

In science, this privilege is earned by not only following conventional norms of honesty and transparency but by supporting one’s opinions with evidence and reasoned argument in the peer-reviewed literature.

This is what makes science self-correcting. If arguments turn out to be wrong, in time they are caught and corrected by other scientists. It is virtually impossible to publish long-refuted nonsense in good peer-reviewed journals.


an overwhelming scientific consensus does not imply the absence of contrarian voices even within the scientific community.

Over time, those contrarian voices simply fade away because no one takes them seriously, despite their shouts of “censorship” and accusations of bias.

This is not to say that a scientific consensus is never overturned.

There are well-known examples such as the Helicobacter pylori discovery in medicine, and continental drift in geology. But in both cases the arguments were won and lost in the peer-reviewed literature, not by contrarians sitting on the side-lines writing opinion pieces about how they were being oppressed.

A ‘change in paradigm’ occurs when the evidence for the prevailing theory is shown to be weak, and the evidence for a competing theory is getting stronger. That is the opposite of what has been happening in climate science over the past 150 years: The evidence of human influence on climate has been steadily accumulating from the time that it was first postulated as a prediction. Arguments against it have been shown to be either wrong or irrelevant for the big picture.

Even more so, the prevailing paradigm (that us tiny humans can’t possibly compete with the great forces of nature in affecting the earth’ climate) has been gradually overturned by the evidence which pointed out that yes, we can.

Oreskes gives a good overview of how climate science stacks up against the scientific methods (Highly recommended: “How do we know we’re not wrong?” slides and book chapter).

Back to The Conversation. Read and shudder:

One self-proclaimed “rocket scientist” who has published junk science in the opinion pages of The Australian has been quoted on aNew Zealandwebsite as saying:

“To win the political aspect of the climate debate, we have to lower the western climate establishment’s credibility with the lay person. And this paper [an accompanying picture book of thermometers] shows how you do it. It simply assembles the most easily understood points that show they are not to be entirely trusted, with lots of pictures and a minimum of text and details. It omits lots of relevant facts and is excruciatingly economical with words simply because the lay person has a very short attention span for climate arguments. The strategy of the paper is to undermine the credibility of the establishment climate scientists. That’s all. There is nothing special science-wise.”

Undermine credibility.

That’s all.

Nothing science-wise.

Are these the people one should entrust with the welfare of future generations?

The tried and tested strategy of sowing doubt in the minds of the public seems to be supplemented by a strategy of lowering the scientists’ credibility. The latter strategy seems to be at least as successful as the former, if recent events are any guide.

PS: I’m well aware that the bulk of public skepticism is not based on a well orchestrated campaign, but stems more from individual reasons (which I’ve discussed in a previous post). That does however not negate the fact that certain lines of reasoning are repeatedly used in the public debate.

Another necessary element of denial is conspiratorial thinking. Any denier sooner or later, whether an academic or not, must resort to a global conspiracy theory to negate the overwhelming evidence arrayed against them.


Just imagine the devastating rebuttal of climate change that Bob Carter could submit for peer-review if he wasn’t being oppressed by the Archbishop of Canterbury and Prince Charles.


Time to close the phony debate on climate science

At a time when the oceans are accumulating heat at the rate of five Hiroshima bombs per second, are conspiracy theorists the people whom a nation should entrust with the future of our children?

The so-called “debate” on climate change has been over for decades in the peer-reviewed literature. It is time to accept the scientific consensus and move on, and to stop giving air-time to the cranks.

It is time for accountability.

Other articles on The Conversation that I enjoyed reading:

Part Two: The greenhouse effect is real: here’s why.

Part Three: Speaking science to climate policy.

Part Seven: When scientists take to the streets it’s time to listen up.

PS: Even though I chose not to use the word “denier” to describe those who don’t accept mainstream science, I did not change it from the original text as quoted. However, I do not intend to host a discussion here on the arguments pro and con of using this or the other label.

Climate skepticism comes in many shades of grey

June 26, 2010

It has long puzzled me why so many people don’t accept the science. There is a tremendous difference in opinion about climate change amongst the lay public as compared to in the scientific community. I’m hardly alone in pondering the question of why (see e.g. this insightful post). It’s clearly an important issue if we are to increase the public’s understanding of climate change. Of course it is only to be expected that some people are skeptical: Naturally there is a spectrum of opinions. But that does not explain why that spectrum is so dramatically different between different groups of people (the lay public and the professional scientists in this case). To name a few plausible reasons:

  • Ideology can be a strong driver of how people view the science: Mitigation of climate change is seen as threatening by many libertarians, because they associate mitigation with government intervention, which they oppose.
  • Psychology can also be very powerful: To some it feels good to be the underdog and get celebrated by anonymous fans on the internet and phoned up routinely by newspapers, TV and other media (that counts for the ‘spokespeople’ only). Many people have a psychological predisposition to side with the underdog (that counts for their fans). The mitigation challenge is very great indeed, which means that it is psychologically favorable to downplay the problem (so as not to get depressed or feeling guilty about everything you do and don’t do). Recently I hear more often that people side with skeptics because they are ‘nicer’. A little odd, but if that plays a major role with presidential elections, than it’s only to be expected that it also plays a role in trusting scientists (or not).
  • Still others suffer from what I call professional deformation: Some well educated people from other disciplines view the science through the lenses of their own specialty, which, if they’re unable to take a bit of a helicopter-view of the situation, could skew their vision.
  • And of course some are just confused. With not a little help from the media, who, in an effort to provide ‘balance’, bias the coverage towards the “skeptical” compared to the mainstream view.
  • Then there are organized efforts at muddying the waters, which bear a resemblance to tactics used by e.g. the tobacco lobby. It is based on manufacturing doubt amongst the public regarding science that produces “inconvenient” results. This mainly applies to certain thinktanks and a few handfuls of individuals, but they exert a disproportionate influence on the media and public perception of the issues. The ‘tactics’ used are in more widespread use, whether consciously or not.

“Old skepticism”

This last category, organized denial and anti-science, could perhaps be seen as the “old skepticism”. It has its roots in history, notably the tobacco wars. It then spilled over to denying environmental issues, such as problems associated with DDT, asbestos, CFC’s, and now CO2. Fred Singer is one of the godfathers of this movement. Recognizing this historical context is important in understanding the nature and tactics of the resistance against science. But it also bears a risk.

Too often, anyone who disagrees with the scientific consensus is called an oil shill, or compared with the tobacco apologists. In most cases, these comparisons are totally off base (at least on the individual level) and counterproductive. Even though it is an important context, overusing this categorization for individuals can easily be dismissed as a conspiracy theory. Not everyone who is skeptical of AGW is in the pay of big oil or is consciously mimicking the tobacco strategies. If someone says that I’ve overused it in the past as well: Guilty as charged.

“New skepticism”

In the previous post I discussed a potential new form of skepticism, which according to some resemble “citizen scientists”. They are usually well educated and skilled people, who investigate specific issues of climate science (hockeysticks, anyone?) in more detail, and find them wanting. Nothing wrong with that of course, but it’s getting problematic if they conflate these details with what is known about the bigger picture, or if they started out with a deep suspicion that the science as a whole is faulty (e.g. for reasons such as stated above).

The more contempt they show for science, the more they argue the big picture of what’s known, the more they rage against emission reductions and talk about ‘world communist governments’ and other paranoid ideas like that, the less serious I take their criticism. Because to me, these are not characteristics of sincere skepticism; to the contrary.

Scott Denning to ICCC Heartland ‘conference’ gathering: “Be skeptical… be very skeptical!”

May 21, 2010

An excellent presentation was given by atmospheric scientist Scott Denning at the Heartland Institute gathering (ICCC 2010), amidst much ‘skeptical’ talk, which is the expected staple over there (h/t Michael Tobis). Both to Denning’s and Heartland’s credit, he was invited to speak there and his talk was apparently well received. How the audience will resolve their inevitable cognitive dissonance remains to be seen.

He makes a number of important points, which are especially apt for a ‘skeptical’ audience:

– The expectation of global warming to result from greenhouse gases is based on common sense and basic physics:

[It is] based on the idea that when we add energy to the surface, it will warm up

Be skeptical of the claim that this extra energy will somehow magically be negated.

Climate sensitivity is around 3 degree for a doubling of CO2 concentrations. This is based on e.g. observations from the Last Glacial Maximum, when the climate forcing was 4.1 W/m2 from greenhouse gases and 3.4 W/m2 from the difference in surface albedo (snow and ice are brighter, and thus more reflective, than water and land surfaces), and the temperature difference with the interglacial that followed was about 6 degrees C.

“No climate models required … just based on observations

(modern calculations agree … coincidence?)”

About a quarter of today’s emissions will stay in the air [semi-] permanently! So when we reduce or stop the burning of fossil fuel, things will not go back to normal for a very long time.

– Historically, 3 degrees C warming is a big deal (e.g. for sea level rise).

– And on how (not) to frame the mitigation challenge:

Then making the obvious point that society didn’t go broke building that very system. To the contrary…

The worst media myth of all: Without the subsidy of cheap fossil energy, civilization will crumble!

Be skeptical… be very skeptical!

He’s not afraid of sarcasm:

You’d think those un-American naysayers had never heard of capitalism …

of the magic of markets …

of the creative genius of a free people!

… or to call a spade a spade:

Alarmist politicians and pundits say:

“(…) If we stop burning coal we’ll freeze in the dark!”


He very effectively changed the frame of the debate:

– The science is about common sense and basic physics

– Who is being ‘alarmist’?

– Being so ‘alarmist’ about the consequences of mitigation efforts is antithetical to having faith in the ‘magic of markets’, entrepeneurship and the power of innovation.

Come to think of it, it is quite surprising that his talk was well received, as there were quite a few digs towards the common way of thinking of undoubtedly many members of the audience. I guess it was delivered with style, respect and humor, and towards the end, he provides his audience with both a mirror and a carrot. There are communications lessons to be learned here. Also, Heartland was clearly happy to have a mainstream scientist present at their party. After all, they crave being taken seriously. The real question however is, did it sink in?

A point of critique could be that he glossed over the mitigation challenge a bit easily, apparently trusting that “the magic of markets” will take care of new energy technologies being invented and implemented. Such a frame may encourage a ‘wait and see’ approach, which I deem risky. I guess a bit of skepticism is at its place whether it will happen so effortless. A lot may depend on how long we keep postponing meaningful emission reductions.

Those who most strongly oppose government intervention would be wise to call for strong early action to avoid really stringent measures becoming necessary later on.

Climate hoax

August 17, 2008


Most people will have heard from at least somebody that this whole global warming story is just a hoax. If you haven’t, a quick internet search will reveal many suggestions in that direction, including from influential people such as a US senator, bestselling authors, etc. It is all a left-wing conspiracy to make us give up our SUV’s and our corrupted lifestyles, and to give the government more power and an alibi to raise taxes. A somewhat milder version claims that scientists perpetrate the global warming scare for financial gain. People actually use the “follow the money” argument to claim that the scientists are lying. That turns the world upside down of course. We’re not in it for the gold, as active blogger/scientist Michael Tobis writes. No coherent explanation is ever given how you could possibly get thousands of scientists on board to support a theory that they (presumably) know to be false. It must be one of the most improbable conspiracy theories that I’ve ever heard.


There indeed was a hoax!

Last year, a research paper was circulated (via a “skeptical” email listserv) in which it was claimed that the increase in atmospheric CO2 came from oceanic bacteria rather than from human activities. It was made to look very real, including equations and scientific jargon. But it was all made up.


The “skeptical” listserv, via which the article got a wide audience, sent out a “hoax alert” 70 minutes later (after they found out that the alleged authors of the paper didn’t exist). But by then the damage was done. Email chains, websites and radio shows were already trumpeting the defeat of the global warming scare.


The author of the fake paper wanted to show that many people in the “skeptical” camp are willing to jump on anything that supports their point of view, irrespective of whether it’s true or not. An interesting interview with the (anonymous) author is here.


An interesting question now is whether the same practical joke could be pulled in the other direction as well: What if somebody made up a bogus paper that made outrageously alarming claims, which go against current evidence? Eg claiming that CO2 absorbs 10 times more infrared radiation than has previously been found, or what have you. I’m sure that somebody, somewhere, would jump on the bandwagon and proclaim that the end of the world as we know it is near. But I’d be surprised if there would be any scientists jumping on that bandwagon. They would probably be skeptical. In the true sense of the word, that is.


The hoax also shows something else: If the proof against anthropogenic global warming (AGW) would be that the extra CO2 in the atmosphere comes from bacteria, doesn’t that imply that CO2 indeed has a significant effect on climate? Otherwise the source of the increase in atmospheric CO2 would be irrelevant for climate change. It shows that many (not all) “skeptics” are not interested in having a coherent explanation for the observations as a whole. There is no global warming, global warming is due to the sun, or to bacteria, or global warming is good for us. You can hear such an inconsistent set of arguments from one and the same person. Apparently, an argument doesn’t need to fit into the big picture, as long as it can be used to support a predetermined and desired notion.

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