Posts Tagged ‘Skeptics’

Science, dissent, polarization and ideology

November 9, 2010

Judith Curry has followed up her post about a positive feedback between politics and science, with which I strongly disagreed, with a number of other posts trying to explain where she’s coming from.  The latest, “no ideologues, part III”, makes a lot more sense than her previous “dogma” posts, and sounds a lot less adversarial. This post is based on my comments over at her blog (here and here).

Her thesis is that climate scientists, the UNFCCC and the IPCC seem to adhere to a certain political ideology. In the case of the IPCC that seems a bit of an absurd notion, but in the case of individuals it seems almost self evident that everybody has some sort of political ideology. She writes:

It is fine for people (and scientists) have political ideologies.  The problem comes in when you use politics to defend your science, and you use science to demand policies. This whole thing seems to me to boil down to the traditional clash of values between the greens and the libertarians.

So does this make more sense?  I think a fairly large number of scientists will sign up to believing this ideology, but few will want to be regarded as ideologues.  Are we getting closer her to clarifying this?  I think so (hope so).

I am wondering to what extent her critique would be better described as the overly defensive attitude and ‘circling of the wagons’ strategy of many mainstream scientists and perhaps the community as a whole. She has described it as such before, and to a certain degree I agree.

She gives Michael Mann (who else?) as an example of voicing a political ideology that exemplifies that of the wider community/UNFCCC/IPCC. The headings she provides above citations from Mann give a certain twist to his words though, and provide more fodder to the label ‘political ideology’. Which may give the appearance of wanting to put his words in a certain light. (perhaps for ideological reasons? – just kidding)

E.g. In #2 on the list Mann talks about what can still be done, whereas in her heading Judith characterizes it as what needs to be done.  #5 has a large disconnect between her heading (action is needed) and Mann’s retelling of historical environmental threats.

She is right though that overall, Mann’s words as quoted are not purely in the realm of science, but nor are they intended to I think. It would be helpful if scientists are more clear as to when they’re talking about science and when they’re talking about something else (their personal opinion about the public debate, politics, ethics, etc). Hansen and the late Schneider are good examples of that IMO. Some may respond that those differences are very obvious already: Why spell them out. Which has (more than) a nucleus of truth as well of course.

I wrote about distinguishing these kinds of issues in a conversation I had with Tom Fuller a while ago, about what the next generation questions regarding climate change are:

Let’s distinguish the following main issues:

– To what extent is climate change occurring, and to what extent is it man-made?

– To what extent is that (going to be) a problem?

– What can or should we do about it?

The first questions are strictly scientific; the middle has a judgment value to it (besides being also based on the forever tentative answer to the first question), and the latter is primarily a political/moral judgement (and has more to do with technology and policymaking than with climate science).

We have made much more progress in addressing the first question than in addressing the last one. The limiting factor in addressing the issues relating to climate change is IMO not a lack of knowledge about the exact nature of the changes; rather, it is the unwillingness of society to deal with (the consequences of) this knowledge. Even if, within realistic boundaries of the uncertainty, climate change is less bad than currently expected, we need to dramatically step up our policy response.

Needless to say, that last sentence is a value laden statement, based on my understanding of the science combined with my value system, risk perception and risk aversion. Or perhaps that is not needless to say? (that’s not a rhetorical question btw).

Judith responded by saying that what she has a problem with is when people or institutions use their ideology “to stifle dissent and scientific debate”. Well, who wouldn’t have a problem with that?

That’s the broad brush again. The dissent from the mainstream scientific view takes a lot of different forms. E.g. there are the arguments such as voiced by Bob that AGW is bunk because of the hockeystick and surface temperature issues (my paraphrasing). I hope you’ll excuse me for not taking such criticism all that serious, where a minor detail is blown up as if it falsifies a whole theory, not unlike claiming that gravity doesn’t exist because that bird in the sky disproves it (argumentum ad absurdum; I’m aware that gravity is a better established (though also still not 100% known) topic than climate change).

These kinds of arguments are very common, whereby the conclusion (AGW is wrong) is miles and miles apart from the reasoning that supposedly led the writer to that conclusion. Which leads me to think that maybe, just maybe, they may have been really arguing in the other direction: from their desired conclusion to an narrative that fits with it. Because in the direction as the argument is stated, it doesn’t make sense.

Am I stifling scientific dissent by saying this? I would hope you agree with me that I’m not. I’m arguing against a (to me) nonsensical critique of the science, which IMO isn’t actually a scientific critique at all (though it’s dressed up to look like it). I.e. I’m not stifling anything and the dissent I’m primarily arguing against is hardly scientific (or charitably only partly scientific).

What most mainstream scientists get so worked up about are these nonsensical critiques on the science and the amount of traction they seem to have gotten.

If you have examples of where *scientific* dissent and debate is being *stifled* (no emails please), I’d like to hear about it.

As I stated before, I agree that in this highly polarized environment scientists have sometimes gotten too defensive in their reaction to the various critiques, because of course, some of the criticism does make sense, and even if the conclusion doesn’t, perhaps the premise purportedlyleading up to the conclusion contains some grains of truth. It doesn’t hurt acknowledging that.

Postscript: Simon Donner has an excellent post on the role of the blogosphere in these kinds of climate discussions and how it relates it to the themes of introspection, de-polarization and letting down our defenses. This is the road towards bridge building.

Aikido: The way of harmony. That’s me doing the throwing (in full harmony of course).


Michael Tobis has a related post, citing an interesting lecture by Mike Mann:

“We have to make it clear that the ice sheets are not Republicans or Democrats – they don’t have a political agenda as they disappear,” said Michael Mann. MT asks: “why the politicization of the non-political parts of the question?” That would be a good question for Judith Curry to ponder.

Chris Colose, who also chimed in over at Curry’s blog, has a post on her ‘dogma’ and ‘ideology’ framing. He finishes by saying:

Finally, we’re going to be endlessly stuck at a cross-roads if discussion is stifled, (…) but a glance into the refereed literature clearly shows this is not the case. (…) We’re also going to be stuck at a cross-road if you perceive the progression toward unanimous [I would have said “broad”] agreement by the informed as a sign of dogma as opposed to robustness of the conclusion. [link added by me]


Citizen science as the new skepticism?

June 23, 2010

Over at Keith’s, I got engaged in a discussion with Judith Curry and others about the well educated skeptics who self identify as ”auditors” of climate science. She claims that

this group is definitely interested in moving the science forward.

The existence and flourishing of technical climate blogs that take a critical stance towards the mainstream scientific view shows that the dualistic view of professional scientists on the one hand and the amateur public on the other hand is too simplistic (especially if the public is deemed ‘ignorant’ of the science). It is clear that there is a continuum of interest, knowledge, skepticism, sincerity, etc amongst the public.

I agree that it’s not constructive to dismiss the expertise and energy of the more scientifically minded critics (“citizen scientists”). But then I would suggest that those sincerely interested clearly distance themselves from the contempt and suspicions raising crowd, since that are the public face of the critics, and it’s severely hampering communication with mainstream scientists and their supporters. Problem is, McIntyre himself has had a major influence in instilling contempt and suspicions into his very wide following. It doesn’t just raise my ire; it’s entirely un-constructive to moving the internet discussion with critics forward (regardless of how it all started). I suggest that those critics who are sincerely interested in moving the science forward engage more with scientists (rather than raging against them).

Citizen science

Judith Curry compares the technically savvy critics with citizen scientists in other disciplines, e.g. biology and astronomy. I think that comparison is only superficially true. In none of those other fields are the citizen scientists contemptuous towards the professional scientists (and vice versa). The ‘normal’ way for citizens to contribute to science is by providing observations; not so much in the interpretation. In none of the other cases I know of are the citizen scientists strongly critical and suspicious of the mainstream science.

Even in cases where the ‘auditors’ have superior technical skills, scientific intuition and broad background knowledge of the field is very important in placing results in context and in making a coherent scientific argument. These (especially the context) are what’s missing in many (not all) of the citizen scientists efforts regarding climate change, and yet, the conclusions are often uncritically taken to be of paramount importance for the field as a whole (e.g. talk of paradgim shift, Galileo and stuff like that).

Oftentimes, the specific details that the citizen scientists focus on and criticize are presented as needing to be resolved before the rest of the science can be discussed, and long before we may discuss policy options. That’s exactly what concerned scientists and citizens fear: That it’s used as an option to delay action (whether intentionally or not).

A constructive discussion about the best public actions to address global warming does notdepend on these technical details at all. That’s the crux of the matter. They make people not see the forest for the trees, in a very effective way. If that’s not McIntyre’s purpose, he should really rethink what he’s doing.

Michael Tobis made the observation that he agrees with the “citizen scientists” on many of their main points, but not on the policy direction. If they would be primarily interested in what they proclaim their key points are, and not in (obstructing) mitigation politics, the rational response would be to welcome Michael as an ally. However, he is “cast as an opponent, even as an extremist”. This is a very important point, and indeed, it suggests that their “real priorities have nothing to do with scientific process”.

In response Judith said that Michael’s stance on mitigation and uncertainties is what the self proclaimed “auditors” respond negatively to. The first point (on mitigation) is exactly what leads to Michael’s conclusion: Their primary interest is politics (disagreeing on the need for mitigation). The second point is untrue and unfair to Michael. He is most definitely not “in denial of uncertainty” as Judith later claimed.

Rather, he often makes the following pertinent points that I wholeheartedly agree with:

  • Some things are known more accurately than others.
  • The big picture of where we’re heading is clear, and this is what’s relevant for policy making.
  • Uncertainty cuts both ways. Combined with the knowledge about the big picture direction and the inertia in the system, uncertainty makes the case for action stronger rather than weaker.

I see a lot of self proclaimed “skeptics” mix up uncertainty with knowing nothing, and use that as an excuse for delaying action on mitigation. That is probably the number 1 argument to delay action. It is a policy statement, masquerading as a concern for science.

Genuine and pseudo skeptics

Undoubtedly climate skepticism comes in many shades of grey (as does climate concern). How can we distinguish between genuine skeptics and pseudo-skeptics? Undoubtedly, all self styles skeptics see themselves as genuine. I don’t really have an answer to that question. But the comparison with other areas of citizen science begs the question of why those in the climate change arena are predominantly critical, contemptuous even, about the mainstream scientific view? If their primary interest was in data analysis or observation quality, such an attitude wouldn’t make a lot of sense. I’d expect a group of citizen scientists to also have a spectrum of opinions on the science, but to see that spectrum go off in a totally different direction than the spectrum of views of professional scientists, is odd. Even if I’d take their criticism on the details at face value (which I don’t; call me skeptical), it doesn’t logically follow that their opinions of the science as a whole, let alone on mitigation, would be dramatically different.

The fact that many “citizen scientists” seem to be have such different views of the big picture makes me think that a sizeable proportion of them did come into this debate with preconceived notions. Something must have picked their interest in the science. Perhaps it’s more likely that they came to this debate with a skeptical inclination, rather than purely based on a love of the science in question, as is the case with archetypical examples of citizen science. This skeptical inclination could have extra-scientific reasons (e.g. psychological, ideological, political, etc) or it could be that criticisms they read about (e.g. from McIntyre) made them question the validity of the science, which they then decided to explore themselves. It’s important to distinguish between the details and the big picture. To what extent do they question the validity of the big picture, while exploring the details? And conflating the two? Without knowing the big picture, the McIntyrian way of looking at things probably sounds very convincing, especially to those from specialized technical fields.

The existing polarization, and subsequent defensive attitude of some spokespeople of mainstream science, may also have contributed to technically savvy people being drawn to ‘the other side’. That’s something we shouldn’t discount as a potentially important factor, and we should try to learn from it. It is clear that mainstream scientists (and their supporters) have not come to grips with these new skeptics, citizen scientists, technically savvy critics, auditors, or whatever name you’d want to give them.

See also some recent posts by Michael Tobis here and here.

Let me end by naming some constructive examples of citizen science:

Clear Climate Code

The making of a sea level study

Temperature reconstructions (and my reply to Lucia at Comment#46143)

Recent examples of citizen journalism also make clear that the less judgment is (perceived to be) passed onto the subject of study, the better it will be received.

CO2 and temperature both increasing: D’Aleo’s attempt at falsification of AGW debunked

March 17, 2010

Below are two graphs of global average temperature and CO2 concentration. First I show the temperature anomaly from the three major datasets of surface temperature together with the CO2 concentration as measured at Mauna Loa since 1958:

The CO2 concentrations are plotted on a logarithmic axis because the temperature effect of CO2 is logarithmic. The 11 year running mean through the yearly temperature anomalies is given by the thick colored lines.

Before the 1970’s, the temperature trend was more or less flat for a few decades (see also the graphs in this earlier post). The strong increase in cooling aerosols (resulting from e.g. SO2 emissions) counteracted much of the greenhouse warming over that period. Since that time however, greenhouse forcing has been dominant, resulting in the temperature and CO2 trends following a similar pattern (at least over the multi-decadal timescale; short term variability is heavily influenced by e.g. El Nino/La Nina, major volcanic eruptions and other natural phenomena). A graph of the time evolution of relevant known climate forcings over the past 130 years can be found here.

A very popular graph that purportedly falsifies the whole “AGW dogma” is the following, showing unrelated trends of temperature and CO2 for a recent 11 year period. It’s been carefully crafted to create a certain impression:

However, this graph is entirely misleading:

There are more factors than only CO2 that influence global average temperature.

The expected trend in temperature does not necessarily rise above the expected level of yearly variability over the course of a decade.

– The graph purposefully starts at a record high temperature (1998) to maximize the visual impression of “falling temperatures”. It also strongly depends on the specific datasets used. This is a clear example of cherrypicking.

Using the same logic as this graph is based on, one could also falsify the theory of gravity by pointing to a bird in the sky (conveniently forgetting that there are more forces than gravity and that the bird has wings).

Contempt for science

September 12, 2009

Some Marc Morano “wisdom” brought to us via Eli Rabett:

(update: This comes from DenialDepot, a satirical website making fun of Morano, though it reflects his thinking pretty well. Thanks Anders and Eli for pointing it out. I’ll keep the post up since its message is still valid.)

I believe that one day all science will be done on blogs because we bloggers are natural skeptics, disbelieving the mainstream and accepting the possibility of any alternative idea.

We stand unimpressed by “textbooks”, “peer review journals” and so-called “facts”. There are no facts, just informed ideas. We are infinitely small compared to nature and can’t grasp anything as certain as a fact.

Let me get this straight: Science is better done by Joe Schmoe than by trained professionals, because Joe doesn’t trust professionals and instead will accept any idea or explanation, no matter how stupid (as long as it confirms their preconceived notion, of course).

So schools: throw away those textbooks! Teach using blogs instead! That will be the return of creationism in the classroom, of how HIV doesn’t cause AIDS and how greenhouse gases don’t influence climate! Free at last, free from the accumulated knowledge as condensed in those textbooks! Let’s go by uninformed ideas instead.

The thing is: Expertise matters. When it concerns your health, you trust a doctor’s opinion more than that of a software engineer. It is not unreasonable to trust a climate scientist more than a doctor when it concerns climate. Of course this is not proof, but there is a difference in likelihood of them knowing what they’re talking about. People know best what they’ve studied the most is a very sensible rule of thumb.

If they would hold the same contempt for their medical doctors as they have for scientists, their health would probably suffer. But at least the consequences for their contempt would fall solely on their own shoulders. With global climate change it’s different.

The NIPCC report: don’t be fooled

June 13, 2009

(Nederlandse samenvatting hier)              (For a sneak preview, see the bottom line below)

The new ammunition put forward by “skeptics” seems to be the Heartland InstitutesNIPCC report 2009 (“Climate change reconsidered”). It is made to resemble, at least in format and in name, the IPCC report. According to Dutch “skeptic” (and contributor to the report) Hans Labohm it completely shatters the AGW (anthropogenic global warming) theory (e.g. here, in Dutch). That’s a very bold assertion, which should be backed up by very strong evidence for it to be taken seriously. Let’s take a look at the executive summary…

Second opinion
The preface starts as follows: “Before facing major surgery, wouldn’t you want a second opinion?”
Now that’s funny. I recently described the IPCC process using the same analogy: If you get a second opinion on your health condition, and it confirms what your specialist said in the first place, your trust in the diagnosis probably increases. Now imagine that you collect the interpretations of medical professionals all over the world, and by and large they their conclusions converge to the same broad picture. This happens to be how the IPCC comes to its conclusions.
Their opening statement is actually a strong argument for going with the consensus position on a complex topic. Yet they use it to argue in the opposite direction; very peculiar.

It continues: “When a nation faces an important decision that risks its economic future, or perhaps the fate of the ecology, it should do the same.” (i.e. getting a second opinion)
Huh? Risking our economic future? If they’re talking about the costs of emission reduction, they are seriously exaggerating. Who is being alarmist here? There will be winners and losers, yes, but that’s something entirely different. Everybody has a choice to join the winners or the losers. Different from the horse races, it’s easy this time to predict who (in the long run) will be the winners and who will be the losers. Take your pick.

The usual stuff
The previous NIPCC report has already been commented on by RealClimate, and it doesn’t seem like there’s much news under the sun this time. The same old and tired arguments feature in the current report. The RealClimate article has many links that debunk the various talking points, and I’m not going to repeat all of them here. A presentation from the lead author, Fred Singer, has been briefly discussed at RealClimate as well. It’s a good example of yet another groundhog day. For those who have followed the staged ‘climate debate’, the list of authors is revealing: Many of the usual suspects, with a history so to speak.

There are the usual, to be expected arguments, like that it’s all the sun’s fault. And logical fallacies, like ‘the climate changed before without human activity being involved, so therefore it must be natural now as well’. Try that line of argument in a court of law against a pyromaniac, by saying that forest fires have always happened naturally. It won’t fly, and it reveals that this report is not about science. The good thing is, with such erroneous lines of reasoning, no specialized knowledge is needed to see that.

Degrees of uncertainty
What I didn’t expect, however, was to see otherwise interesting research be put in a context as if it somehow “falsifies the AGW theory”. In many cases, it hardly has any relevance to the attribution of current climate change, or to future projections.

Ironically, their main argument against climate modeling is its associated uncertainty (mistaking it for knowing nothing, and ignoring that uncertainty goes both ways). That doesn’t stop them from putting forward hypothetical feedbacks that have no evidence whatsoever of operating on a globally significant scale. By the way, climate modeling is mocked in the report as merely being “the opinions of scientists transformed by mathematics and obscured by complex writing”. Doesn’t sound like they know what a climate model really is.

The report goes on to describe many hypothetical feedbacks in the climate system. Of course, they are all negative: They counteract the initial warming, independent of the cause for the warming. Their combined effect, is the hope, should be evidence that the climate sensitivity is an order of magnitude (!) smaller than the commonly accepted range (between 1.5 and 4.5 degrees C for a doubling of CO2). Not just 50%, no, a factor of 10, I kid you not. My alarm bells go off. Let’s see what the implications of such low climate sensitivity would be. Any climate forcing (whether natural or human induced) would be so strongly damped as to hardly have any effect on global temperatures. But then how come the globe is warming, and has warmed and cooled in the past? A logical consequence of their theory (negligible climate sensitivity) is that it’s hardly possible for the earth’s climate to change. Indeed, there is no physics-based climate model that can satisfactorily model both the current and past climates with such low climate sensitivity.

Many of the proposed feedbacks involve the cooling effects of aerosols. They suggest that these cooling effects are larger than reported by the IPCC. That is contradicted by climate models providing a very decent match to the observed cooling following a major volcanic eruption (emitting sulfate aerosol in the stratosphere). Moreover, some have argued that a strong aerosol radiative forcing means that the climate sensitivity has to be large in order to still be able to explain the temperature trend of the last 100 years, so they seem to be shooting in their own foot.

They come up with all kinds of hypothetical feedback mechanisms involving more natural aerosol emissions in response to global warming: Dimethylsulfide from marine phytoplankton (although a very intriguing possibility, this has never been confirmed to be a significant feedback mechanism, and there is ample evidence to the contrary, which is omitted from the report), biological aerosols (idem), carbonyl sulfide (idem), nitrous oxide (idem), and iodocompounds (idem), about which they write the following:
“Iodocompounds—created by marine algae— function as cloud condensation nuclei, which help create new clouds that reflect more incoming solar radiation back to space and thereby cool the planet.”
Nou breekt mijn klomp (“Now my clogg breaks”), as I would say in Dutch. This route to atmospheric particle formation may be important at coastal sites with exposed seaweed, but its global importance is questionable to say the very least; at present it could best be considered an interesting thought experiment. Moreover, freshly nucleated particles have to grow by about a factor of 100,000 in mass before they start affecting climate, and a lot can happen to them before they reach the necessary size.

All very interesting research topics, but to claim that they are somehow evidence for negligible climate sensitivity is an extreme example of over-interpretation. In these active areas of research, where no firm conclusions have been reached yet on global significance, they selectively cite only those articles that they can somehow spin to support their desired conclusion. I feel that I’ve read enough of this report to know what it’s worth.

Bottom line
This report exhumes a very strong and unfounded faith in negative feedbacks from nature, which are hypothetical with sometimes sketchy, often contradictory, and sometimes no evidence of actually operating at a globally significant scale. This highlights an inconsistent view of uncertainty, and an unwillingness to weigh the evidence: “If it causes cooling, the uncertainty (or lack of evidence) doesn’t matter; if it causes warming, it’s too uncertain (and no evidence strong enough) to matter”.

How would you know?
Let’s apply some of my own recommendations for non-specialists on judging sources:
– The report clearly misses the forest for the trees.
– It gives a hidden argument for going with the consensus (“second opinion”), but somehow twists that around.
– It’s characterization of the IPCC process has the smell of a conspiracy to it and is full of strawmen arguments.
– To their credit (and my surprise), I couldn’t find any obvious confusion of timescales, such as confusing weather and climate.
– It contains some embarrassing mistakes in basic logic.
– The two way cause-effect relationship between temperature and CO2 is not properly recognized.
– Their strong claim of shaking the foundations of climate science is extremely unlikely; They don’t provide compelling evidence for such an extraordinary claim; They vastly overestimate the likelihood of cooling effects (feedbacks), and underestimate, deny or ignore warming effects.
– They grossly exaggerate the economic risks of emission reduction, and downplay the risk of unmitigated climate change.
– Some of the authors have historical credentials in a relevant discipline, more than a few have not. The list of signatories at the end is very thin on relevant expertise.
– The Heartland Institute is a conservative think-tank and not a reliable source of scientific information.

Climate solutions

June 4, 2009

The public debate about the reality of human-induced climate change is perhaps mostly interesting from a psychology point of view: How come some people embrace the wishful thinking and flakey arguments from small splinter groups and distrust the evidence-based conclusions from the vast majority of relevant scientists? I think that in many cases the answer is that they don’t like the perceived consequences. In other cases it’s a matter of thinking along familiar lines. And for some, it may be the attraction of being the underdog, which, in extreme cases, leads some to think of themselves as (supporting) the new Galileo. And yet others may have been fooled into thinking that there still is a real scientific debate about the big picture (with not a little help from the popular media). After all, without reading the primary literature or attending relevant conferences, how would you know who is right? 

The more relevant discussion for society is about how to deal with climate change. How do we act in the face of uncertainty, but with real risks of problematic consequences? “Skeptics” could make a very useful contribution to such a discussion, if they started thinking about how to deal with climate change while at the same time minimizing the perceived consequences they dislike so much (e.g. taxes and regulations).

Waiting until disaster strikes (as desired ‘proof’) before starting to deal with the problem, is not a rational option. If a doctor is 90% certain that you have a dangerous illness, you probably want to start treatment as soon as possible. Or would you wait with treatment until the doctor is 99% or 100% certain? The problem is, doctors and scientists are never 100% certain.


So what do we do?


I’ll be writing more about this question in the near future. Specific topics that I intend to discuss are geo-engineering (intentional engineering of the Earth’s climate), biomass, transport options (biomass/hydrogen/electric powered vehicles), and others. These are not all clear-cut ‘solutions’, and their suitability in dealing with the problem is vigorously debated, including in the scientific arena. Finally some real debate, rather than the fake stuff.

Professional deformation

September 25, 2008

(Nederlandse versie hier)


A meteorologist and a chemist were discussing the cause of the unexpected isoprene concentrations at a forest site (isoprene is an organic compound emitted by trees). The meteorologist thought it was most likely caused by some specific boundary layer dynamics, whereas the chemist thought that perhaps some unexpected chemical reaction was taking place. What did I learn from witnessing this discussion?



Everybody has a natural tendency to think along familiar lines. And to a certain extent, it makes sense: If you’re much more familiar with meteorology than with chemistry, then of course most explanations you can come up with are meteorological in nature. And as long as you are fair in weighing your thoughts and specific evidence alongside those coming from other disciplines, then there’s no problem. By discussing the relative merits of different explanations, you can hopefully come to a conclusion (dare I say “consensus”) as to what is most likely the case, taking all evidence into account.



Problems may arise when you downplay explanations coming from other relevant disciplines, being all too sure that the explanation is to be found within the realms of your specialty. If in doing so you ignore evidence to the contrary, chances are you’re in denial.



The theory of continental drift was rejected by some influential geologists in the early 20th century. In an excellent presentation, Oreskes sais of one of them, Bowie, that he did so “wholly on the basis of geodetic evidence (from his own specialty), and ignored the large body of data from various other geological specialties that independently argued in favor of continental drift.” She goes on to say that “we all gravitate towards certain kinds of evidence and arguments, and they tend to be the ones with which we are most familiar.”


Professional deformation

This “professional deformation” of favoring familiar lines of evidence, while ignoring that from other disciplines, is also happening in the climate debate: Examples abound of meteorologists who point to the chaotic nature of weather and turbulence, of geologists who point to massive climate changes in the past, of astronomers or solar physicists who point to the sun as the main driver of climate change, etc. Such claims are often so called half-truths.


These are all specialties that are related to the broad field of climate science, and as such they often make very useful contributions to the field. But some individual scientists make strong and contrarian claims about climate change, rooted in their own specialty, while ignoring the vast body of data and evidence from various other disciplines that independently argue in favor of the scientific consensus. That’s a red flag for taking their opinions on climate science with a grain of salt, even though they may be perfectly capable and honest scientists in their specialty. A multidisciplinary view is not everyone’s cup of tea.



The feeling of being the new Galileo, the misunderstood underdog fighting “the scientific establishment”, may be an important psychological drive for “skeptical” scientists. This feeling is amplified by a big fan-club cheering them on from the sideline (in the popular media).


In addition to the explanation given by Oreskes above, I think that many people tend to gravitate towards the kinds of evidence of which we like the perceived consequences best. With continental drift nobody besides geologists could care less what scientific consensus would be reached, but that’s a different story with global warming. Those who are afraid of the solution (predicting economic doom) find an easy way out, psychologically speaking, by ignoring or denying the problem, e.g. by holding on to even the flimsiest piece of evidence to the contrary. They are more of the “anything-but-CO2” kind, and they constitute the fan-club mentioned above.


Btw, the meteorologist was most likely correct, as I could show with a 1 dimensional box model.

KNMI: The state of the climate

August 6, 2008


The 5 yearly report “The state of the Climate” (in Dutch only) has just been released by the KNMI (Royal Dutch Meteorological Institute). It’s focused on the Dutch climate, but put in a global perspective, and it’s aimed at governments, organizations, and the general public. A main conclusion is that The Netherlands has warmed up more than twice as fast as the global average.


That’s in principle not so surprising, because land warms up faster than oceans. The extra warmth is being mixed (and thus tampered) in the upper water column, and water has a large heat capacity (which causes it to warm up less with the same input of energy). Indeed, most of Europe has warmed faster than the global average. The Netherlands also has also gotten more precipitation during the past 100 years.


Dutch and global temperature (anomaly) trends 1950-2008

Dutch and global temperature (anomaly) trends 1950-2008


Figure 2.1 from the report shows that the temperature in The Netherlands fluctuates much more than the global temperature. That makes perfect sense, because random variations are averaged out to a greater extent when more measurements are included. That is valid for more measurements in space (global versus Dutch) and e.g. also for more measurements in time (40 versus 5 years).  Logical as this may be, you would be surprised how often anthropogenic climate change is being denied, based on 5 (sometimes even 1) year temperature trends, or based on that one glacier in Africa (or was it the Himalaya?) that has increased in length. You can easily find these kinds of arguments on the internet and certain other media (but you won’t hear them at a scientific conference). That has the positive side effect that it can act as a warning signal that the information on such a website is not scientifically sound (even though they often try very hard to make it appear scientific).


The discussion about the temperature trends ends with the statement that “a connection with the enhanced greenhouse effect seems logical, but hasn’t been shown/proven yet” (my translation). Such a sentence seems more geared towards scientists than the general audience, which is the stated target group of the report. I think that the uncertainty here is mainly a consequence of the large variability of the temperature signal over a small area (as discussed above), and that makes it difficult to draw hard conclusions from it (in comparison to global temperature trends). And of course, there is no strict proof in the mathematical sense (nor will there ever be).


Most readers of the report will interpret this very differently however. Many will interpret it as meaning that it’s quite possible that the (local or global?) temperature rise has nothing to do with rising greenhouse gases. However, the chance of that being the case is very small indeed. Uncertainty has a very different meaning in the scientific jargon than in daily language. Oftentimes, science communication fails to convey a proper understanding of the relative (un)certainty, which is a shame.

Anything but CO2

July 31, 2008

(Nederlandse versie hier)

When I ask my wife what kind of tea she wants, she often replies “anything but green”. (I have gradually learned to then refrain from saying that green tea is good for you). Likewise, an honest “skeptic” would reply to the question what causes global warming, “anything but CO2”. After all, that seems to be the red line in their thinking. Whereas liking green tea or not is a matter of taste, attributing part of the current climate change to CO2 is a matter of science (and that’s a different cup of tea alltogether).



Real skepticism is central to science; after all, science works on the basis of evidence, and the evidence has to withstand critical investigation. However, continuously raising doubt about scientific understanding, which has long been established as true beyond reasonable doubt, is not always useful to science. Especially not when in order to do so, scientific shortcuts are taken (i.e. cherrypicking of data, ignoring basic physics, logical fallacies, etc). People who do the latter are what I call “skeptics”. In quotation marks, because their actual attitude has nothing to do with skepticism. They typically are totally uncritical in accepting any theory that puts the blame for global warming on something different than CO2 (preferably something natural, like the sun). And they are often irrational in pushing aside the multiple lines of evidence in support of the enhanced greenhouse effect.

That of course gave rise to a whole range of other names for so-called “skeptics”, which better describe their attitude. But the fact is that in the public discussion they are still best known as “skeptics”, which is why I use that name. Besides, some other names that have been suggested, such as denier, can be offensive because of their association wiith some black pages of history. Contrarians, denialists, delayers, are other terms being used. But what’s in the name.

Scientific “skeptics”

Of course it’s not all black and white. Someone who is critical of certain aspects of climate science, can actually contribute a great deal to the field. As long as (s)he adheres to the scientific method and does not go into a knee-jerk “anything but CO2” mode. Some scientists, who were once skeptical, now turned “skeptical”, and their scientific opinion seems to be set in stone, unchangeable by evidence to the contrary. Many more scientists who were once skeptical have over time become convinced by the accumulating evidence for human induced climate change. And of course there are still scientists who are sincerely skeptical. However, they are at least as rare as the “skeptics”.

Ideological “skeptics”

There are a number of vocal “skeptics” out there who don’t appear to be the least interested in increasing scientific understanding, but rather in promoting a political agenda. They distort and abuse the science in order to use it as an argument for inaction. They are often linked to right-wing think-tanks and some of them were also involved in trying to halt anti-smoking regulation by arguing that negative health effects of smoking were not proven. Any public statement they make about science is accompanied by a statement in favor of laissez faire politics. Their opinion about climate science seems to be driven by their political opinion, rather than vice versa.

Unfortunately, they have been hugely successful in stalling meaningful regulation, despite their relatively small number. Through their anything-but-CO2 attitude, they have made themselves irrelevant to the scientific discussion. However, we keep hearing from them via the media, who provide them with a platform to sprout their disinformation, as if they have anything useful to say about climate science. Wouldn’t it be better if reporting about science reflects the current scientific knowledge? Would it make sense to keep hearing that there is no causal relation between smoking and health (despite mounting evidence to the contrary)?

Ideological “skepctics” are cheating. It would be better if they backed up their political opinion with their real arguments, rather than presenting pseudo-scientific nonsense as as reason. If there were no greenhouse effect, there would be no life on Earth. Deal with it.

Climate “skeptics” out of touch with reality

July 22, 2008


This is a reply to a Dutch article which quotes Fred Singer as claiming that CO2 has hardly any effect on climate; that climate change is due to the sun; that global warming stopped in 1998; and that sealevel won’t rise faster than it has done in the past thousands of years. I wrote the following reply.
(Nederlandse versie hier.)


The premise that CO2 has hardly any influence on climate, as argued by Fred Singer, can not be sustained. These so-called “critical” opinions may fare well in the media, but in the current scientific debate they don’t play any role. They have been proven wrong long ago.


The current media don’t pay much attention anymore to claims that smoking wouldn’t have adverse health effects (something Singer argued in the past). Or to claims that CFC’s wouldn’t destroy the ozone layer (Singer also argued that, until just before the Nobel Prize for Chemistry was awarded to those who showed that they do). It’s about time that the media also start portraying climate change in line with current scientific knowledge.


CO2 and global warming: hypothesis or fact?

It has been known for over 100 years that CO2 absorbs infrared radiation, and thus has a warming effect. This effect causes the Earth to have a hospitable climate, and Venus to be boiling hot. Of course there are uncertainties in climate science, but our knowledge has definitely progressed a few stations beyond what Singer and a handful of other (ex-) scientists claim.


The observed change in temperature over the past 100 years is reasonably well reproduced by climate models. The past 10 years do not change that picture, although it has to be noted that temperature changes over a decade (or less) are heavily influenced by the changeable weather, large volcanoes and the El Niño (1998) / La Niña (2007) cycle.


There are a few things that are now beyond reasonable doubt:

–     Global climate has warmed over the past ~100 years, with the largest increase in temperature from about 1975.

–     The concentration of CO2 and other greenhouse gases has increased due to human activity.

–     Basic physics and numerous observations point to a causal relationship.

–     Further increase in greenhouse gas emissions will lead to further warming.


Other factors

Of course there are other factors besides greenhouse gases that can influence the climate, such as aerosols, land use, solar activity, etc. The sun is often put forward by “skeptics” as being the main reason for the current warming. But although the increase in solar activity in the first half of the 20th century indeed contributed to the warming, the solar activity (and related quantities such as cosmic rays) has remained more or less constant since the sixties. The strong increase in temperature from 1975 onwards can therefore not be explained by varying output of the sun.


An alternative explanation of current climate change can not just put aside the accumulated body of knowledge and observations; they have to be integrated into a total picture. The infrared absorbing ability of greenhouse gases can not just be denied by pointing to the sun. You don’t deny gravity either when you see a bird fly.


Sea level rise

Sea level is rising faster than it has in the past (before 1900), and also faster than predicted by climate models. The possibility of (mechanically) enhanced melt of land ice is an active research area where knowledge is still lacking. But this uncertainty should not be a comfort, because the risks of a substantial sea level rise are large. Many of the large population centers are located in the vicinity of the sea at only small elevation.



Singers unfounded opinion about CO2 is not relevant for the discussion about energy options, just as his opinion about smoking is not relevant for the discussion of anti-smoking laws. About policy options, for example concerning energy, there will always be different opinions. And different opinions should be heard. But please leave out scientifically proven untruths. They don’t contribute to the debate. To the contrary.

%d bloggers like this: