Sunday, 30 March 2014

The BBC will continue fake debates on climate science

Nigel Lawson
Nigel Lawson, not a scientist, but confuses public about science helped by the BBC.
David Rose wrote in The Daily Mail that Mr MacLeod, head of editorial standards and compliance for BBC Scotland, sent an email to his colleagues:
"When covering climate change stories, we should not run debates / discussions directly between scientists and sceptics. If a programme does run such a discussion, it will... be in breach of the editorial guidelines on impartiality."
Anthony Watts wrote a response in his usual elderly statesman manner; it was titled: "Climate change campaigners fear debate, can’t face climate skeptics anymore, so they rig TV news shows". No link, you can find the cesspit yourself. Note the word fear that is so important to the conservatives and the concealed message that climate scientists are climate change campaigners.

The Daily Mail is not the most reliable source around. The only article missing in the side bar is "Britney beheaded two-headed baby in satanic ritual". Thus I have asked the BBC for confirmation. They replied:
[I]t is not the case that “the new policy of the BBC is to no longer have debates between climate scientists & climate "sceptics"” as you state – our policy is and remains that all views are given due weight in BBC coverage of the issue.
Sounds like the bad news for Watts' blood pressure and the good news for science and democracy is wrong. The BBC will continue having fake debates on climate science. Or at least there does not seem to be a BBC-wide consensus opinion yet. What I found especially worrying is that the BBC does not distinguish between false balance ("due weight") and fake public debates. They are related, but separate problems.

What is wrong with the media?

Why is this a problem for democracy? I would like to explain the importance of accurate media reporting on climate science using a great new video that was just released called Can we trust scientists? h/t The New Anthropocene.

It reminds us of the huge trust the public has in science and contrasts it to the large percentage of people holding opinions that deviate from the scientific consensus. Not only when it comes to climate change, but also evolution and vaccination.

It argues that people who know of the consensus generally accept it. This makes sense because a consensus opinion is much more reliable as the opinion of single persons. However, many people have the wrong impression that scientists are not sure yet whether climate change is a problem. Also the climate dissenters often claim there is no consensus.

As a consequence climate scientists are forced to state that there is a consensus on the basics. A somewhat awkward position as the job of a scientist is to refute existing hypothesis and there is nothing more beautiful for a scientist to refute a consensus idea. That means you are better than all the others. Or more modestly, that you were lucky and had a better idea. :-)

The video argues that vocal individual dissenters and the press are responsible for the misperception of how sure scientists are that climate change is real. The problem with the press is that they like controversy and that they present both sides as equal.

I think that the press is just part of the problem. Some people seem really determined not to understand what science has found. And I am not so sure whether the solution presented in the video, reading and watching bloggers and YouTube v-bloggers, will help. But maybe WUWT and Co. have damaged my trust in blogging. Apart from that, this is a video well worth watching and sharing.

False balance

I have this vision of a few theoretical physicists leaving the Large Hadron Collider after a long night of experiments, and stopping in at the local pub for a drink, where a few of the rowdier locals decide to challenge them on the fundamentals of quantum chromodynamics and a nonsense argument (debate) ensues.
David Sanger

Saturday, 15 March 2014

Do dissenters like climate change?

Ronald McDonald enjoying himself after Hurricane Katrina.

The kind of "conversations" I am having in the so-called climate "debate" made no sense to me until I asked myself the question whether climate dissenters might like climate change? Maybe a strange question, but it would explain a lot about the debate.

Take Watts Up With That (WUWT), the largest climate dissenter blog. The mainstream opposition of the IPCC. Every post I have read there on a topic where I am knowledgeable contains serious errors. The other posts are likely not better. HotWhopper finds errors on WUWT that make one cringe every single day.

But almost no one at WUWT seems to care about these errors. If anything they cheer the loudest when Lord Monckton has a guest post. These posts probably deserve the prize for the highest error density. Or as Barry Bickmore eloquently writes:
Lord Monckton is a living symbol of the fact that many climate change contrarians will believe anything that seems to support their case, even if it’s coming from the most ridiculous source.
And it is not just that science is overtaxing these people, also very simple to check cases of misquotations of a paper on global water vapor or misleading statements about the web traffic of WUWT are accepted without critique. I informed the WUWT audience of the misquotation, but no one cared. If I may quote one of my last comments:
[N]o one here complained about being misinformed. No one said, I do not believe in climate change, but Forest Mims misinformed me and that is wrong. I do not like being misinformed and I feel that this gives our community a bad reputation.
They were happy to discuss any other typical climate ostrich meme or ask: "Do you feel any amount of shame for helping promote death?" The clear misquotation was not interesting, however. That is not what one would expect from a group that wants to develop an alternative to mainstream science.

In discussions with dissenters I get the impression that they make a determined effort not to understand what the others write. This is especially visible on twitter where you only have 140 characters and cannot be very precise. With colleagues and people that accept the science, this imprecision is no problem, they make an effort to understand you and normally manage to interpret the text in the intended way. I try to avoid such "discussions" on twitter, but see others try and end up in endless twitter streams that go nowhere. As an example, see this post by AndThenTheresPhysics about a discussion on twitter and elsewhere on whether greenhouse gases warm or cool :-) the Earth surface temperature.

Such unproductive discussions are unlike anything I know and especially unlike anything I am used to among scientists. Climate dissenters, for example, often dodge the discussion by moving to new topics before agreement on first topic is made. That does not give the impression that the dissenter wants to understand the reason for the difference of opinion. And it does not show much confidence that one's opinion holds up to scrutiny. In the scientific community, you stay at one topic, try to find out where you agree, where you do not agree and why you do not agree. Until you arrive at statements that are so simple that rational persons can agree upon whether it is true or not or what research would need to be done to verify them.

This part of the rant is getting too long. Let me just state that I do not have the impression that the climate dissenters want to understand the climate better. They mainly seem to want to have some fake "arguments" for discussions, to have some fodder to annoy greenies.

This impression fits to the large differences in acceptance of the science between political groups. The rather remarkable consensus of the US Tea party supporters is that global warming does not pose much risk, for example. This suggests that people arrive at their opinion about climate science based on their political positions and not based on arguments. It could be that the dissenters just find science largely irrelevant compared to their political views and good relations with peers who hold similar views. However, it may go beyond that, I have the impression that the climate dissenters do accept the science and are just mocking opposition, because they do not trust themselves to say that they like climate change. Partially their liking may also be subconscious. Humans are complex.

Salmonella infection

Before I explain why climate dissenters may like climate change, I have to make a detour and explain how a Salmonella infection works. I do not want to compare climate dissenters with a disease, but I need the mechanism. If someone knows a similar evolutionary mechanism for cute fluffy animals with big eyes, please tell me so in the comments, then I will replace this part.

Evolution is a beautiful topic. Many people just think of survival of the fittest and in the worst case think that this fitness has to do with building as much muscle as possible in the fitness studio. The intricacies of evolution are well illustrated by the famous creed: "Evolution is cleverer than you are." Also the evolved behavior of Salmonella about with I learned a year ago via a Nature article (pay-walled, press release) is full of beautiful surprises.

Salmonella attacks the intestinal lining of the gut and thus provokes an immune response. What I had not realized is that this immune response actually helps Salmonella to reproduce. While the immune response also hurts Salmonella, it hurts the other bacteria much more and thus makes the niche for Salmonella larger. They are suffering, but the others suffer more. Relative suffering is their survival strategy. That is the mechanism that is important for this post.

Producing the proteins that provoking the immune system comes at a cost. Thus Salmonella bacteria that do not produce them can reproduce faster. Mutant Salmonella bacteria that are just as good in withstanding the immune system, but do not help in provoking it, thus have a fitness advantage. From the perspective of a sick human it is somewhat strange, but from the Salmonella perspective the active bacteria are altruists that help the other Salmonella and the passive mutant Salmonella are the parasitic free-riders.

Once the mutant Salmonella gain the overhand, the immune system goes down and the other bacteria again grow strong and remove the mutant Salmonella, which is the end of the infection.

Relative suffering

This mechanism was what made me wonder whether some people might like climate change. Yes, it will bring suffering over everyone, but they may think that others will suffer more than they will (and their children) and that climate change thus improves their relative fitness.

Thursday, 13 March 2014

Why doesn't Big Oil fund alternative climate research?

A short post. Asking the question is answering the question.

Jo Nova, an Australian climate ostrich, is begging for money to keep blogging. Anthony Watts helped her with an appeal to his readers. Below his post "ClimateReason" complains:
"We are woefully underfunded and under resourced. Every sceptic I know of has to fund their own projects and have jobs unrelated to their interest in climate.

It takes me a year to research my large articles. Who funds me? No-one. Can I afford the time and money? No. Could I do more if Big Oil funded me? Of course. But they don’t, because money from this source for sceptics is completely imaginary. "
Big Oil prefer to give their money to politicians and PR firms, not to research. That Big Oil does not fund research suggests that even they think mainstream science is solid.

Very solid. If they had just the smallest bit of doubt, it would pay off for them to fund studies on climate change big time. They have so much to lose that money would be largely irrelevant. They already do much research themselves and also fund much external research. Universities get funding from oil companies for a large range of other research topics. Thus the structures are in place, the money is there.

If I had a good idea and could not get funding from national funding agencies, I would have no problem with accepting money from companies. My university certainly would not.

Not that I not expect to have problems with a research proposal because it would challenge the mainstream. On the contrary, I expect that a proposal that challenges the mainstream would have more chances of being funded. Is anything more beautiful fundamental research? Another rhetorical question. However, maybe for more speculative ideas, that are likely to fail, the profit motive of an oil company could improve my funding opportunities. Most scientists would be happy to use such an opportunity.

Poor climate ostriches, not even their oil companies believe in them.

Sunday, 9 March 2014

The ultimatum game, a key experiment showing intrinsic fairness and altruism among strangers

Knowledge will come only if economics can be reoriented to the study of man as he is and the economic system as it actually exists.
Ronald Coase

There is a line of economic research on altruism that get only little attention in the media, which is why I want to report on it here. There is by now solid evidence that humans can behave altruistically towards strangers. This is surprising because a naive version of evolutionary theory would expect that altruism is only possible among kin. It also goes against the basic assumptions of economics, game theory and public choice theory, which all assume that humans only have an eye for their self-interest. These assumptions are often defended referring to evolution by stating that you need to be an unapologetic egoist for optimal reproduction. I mention this, because non-academics may think it is natural to assume humans can be altruistic and wonder why one would research something that trivial.

It is not controversial science. There are hundreds of scientists working on it. Almost every month Nature or Science publishes an article on altruism. And at the University of Bonn, where I work, Reinhard Selten is emeritus professor and got his Nobel price for experimental research on the ultimatum game. That is also how I heard about it, our University Magazine had an article on Selten and this beautiful experiments.

In a social setting, where there is an opportunity to build up a reputation, altruism can be explained. In this case, altruism may lead to future benefits and one may even argue that it is thus not real altruism. However, this type of altruism is expected to break down when a group is under pressure and may soon dissolve, but humans also collaborate under such difficult circumstances. Furthermore, reputation-building naturally does not work under conditions of anonymity, while experiments show that humans also collaborate with strangers they will never see again. Our ability to collaborate with non-kin is an important innovation that contributes much to our success as dominant animals.

Ultimatum game

A very simple and pure economic game, which thus shows the problem very clearly, is the ultimatum game (Güth et al., 1982). In the ultimatum game, two players must divide a sum of money. The first player has to propose a certain division. The second player (responder) can accept this division or reject it; in the latter case both players do not receive any money. In its purest form, the experiment is played only once and anonymously with players that do not know each other.

When the article described the experiment, I wondered what was interesting about that. Naturally people offer 50% and the responder accepts this. Not? That only showed my lack of economic training.

Wednesday, 5 March 2014

Be careful with the new daily temperature dataset from Berkeley

The Berkeley Earth Surface Temperature project now also provides daily temperature data. On the one hand this is an important improvement, that we now have a global dataset with homogenized daily data. On the other hand, there was a reason that climatologists did not publish a global daily dataset yet. Homogenization of daily data is difficult and the data provided by Berkeley is likely better than analyzing raw data, but still insufficient for robust conclusions about changes in extreme weather and weather variability.

The new dataset is introuduced by Zeke Hausfather and Robert Rohde on Real Climate:
Daily temperature data is an important tool to help measure changes in extremes like heat waves and cold spells. To date, only raw quality controlled (but not homogenized) daily temperature data has been available through GHCN-Daily and similar sources. Using this data is problematic when looking at long-term trends, as localized biases like station moves, time of observation changes, and instrument changes can introduce significant biases.

For example, if you were studying the history of extreme heat in Chicago, you would find a slew of days in the late 1930s and early 1940s where the station currently at the Chicago O’Hare airport reported daily max temperatures above 45 degrees C (113 F). It turns out that, prior to the airport’s construction, the station now associated with the airport was on the top of a black roofed building closer to the city. This is a common occurrence for stations in the U.S., where many stations were moved from city cores to newly constructed airports or wastewater treatment plants in the 1940s. Using the raw data without correcting for these sorts of bias would not be particularly helpful in understanding changes in extremes.

The post explains in more detail how the BEST daily method works and presents some beautiful visualizations and videos of the data. Worth reading in detail.

Daily homogenization

When I understand the homogenization procedure of BEST right, it is based on their methods for the monthly mean temperature and this only accounts for non-climatic changes (inhomogeneities) in the mean temperature.

The example of a move from black roof in a city to an airport is also a good example that not only the mean can change. The black roof will show more variability because on hot sunny days the warm bias is larger than on windy cloudy days. Thus part of this variability is variability in solar insolation and wind.

Also the urban heat island could be a source of variability, the UHI is strongest on wind and cloud free days. Thus part of the variability in observed temperature will be due to variability in wind and clouds.

A nice illustration of the problem can be found in a recent article by Blair Trewin. He compares the distribution of two stations, one in a city near the coast and one at an airport more inland. In the past the station was in the city, nowadays it is at the airport. The modern measurements in the city that are shown below have been made to study the influence of this change.

For this plot he computed the 0th to the 100th percentile. The 50th percentile is the median, 50% of the data has a lower value. The 10th percentile is the value where 10% of the data is smaller, and so on. The 0th and 100th percentile in this plot are the minimum and maximum. What is displayed is the temperature difference between these percentiles. On average the difference is about 2°C, the airport is warmer. However, for the higher percentiles (95th) the difference is much larger. Trewin explains this by cooling of the city station by a land-sea circulation (sea breeze) often seen on hot summer days. For the highest percentiles (99th), the difference becomes smaller again because offshore wind override the sea breeze.

Clearly if you would homogenize this time series for the transition from the coast to the inland by only correcting the mean, you would still have a large inhomogeneity in the higher percentiles, which would still lead to non-climatic spurious trends in hot weather.

Thus we would need a bias correction of the complete probability distribution and not just its mean.

Or we should homogenize the indices we are interested in, for example percentiles or the number of days above 40°C. etc. The BEST algorithm being fully automatic could be well suited for such an approach.

Tuesday, 4 March 2014

Falsifiable and falsification in science

"You keep using that word. I do not think it means what you think it means."

In a recent post, Interesting what the interesting Judith Curry finds interesting, I stated that "it is very easy to falsify the theory of global warming by greenhouse gasses." The ensuing discussions suggest that it could be interesting to write a little more about the role of falsifiable hypotheses and falsification in science. The main problem is that people confuse falsifiable and falsification, often do not even seem to notice there is a difference, whereas they have very different roles in science.

The power of science and falsification are beautifully illustrated in this video by asking normal people on the street to discover the rule behind a number sequence (h/t U Know I Speak Sense).


Karl Popper only asked himself what distinguishes a scientific hypothesis from an ordinary idea.
Popper's beautiful thesis was that you can distinguish between a scientific and a non-scientific statement by asking oneself if it can be falsified. If it cannot, it is not science. Thus the worst one can say about an idea that is supposed to be scientific is that it is not even wrong.

Important side remark: Please, note that also non-scientific ideas can be valuable, Popper's philosophy itself is not science, just like most philosophy, political ideas, literature and religion.

And please note that wrong hypotheses are also scientific statements; that they are wrong automatically shows that they can be falsified. Even falsified hypothesis are still scientific hypothesis and can even still be useful. An good example would be classical mechanics. This illustrates that Popper did not think about whether hypothesis were right or wrong (falsified), useful or not, but whether a statement is scientific or not scientific.

To be falsifiable, falsification is only needed to be possible in principle. It does not matter whether falsification would be hard or easy for the question whether it is science. This is because the main value of the criterion is that it forces you to write up very clearly, very precisely what you are thinking. That allows other scientists to repeat your work, test the idea and build upon it. It is not about falsification, but about clarity.

That also implies that the daily job of a scientist is not to falsify hypothesis, especially not solid and well-validated ones. Scientists are also not writing down new falsifiable hypothesis most of the time, in fact they rarely do so. Those are the rare Eukeka moments.

The terms scientist and science are clearly much broader and also much harder to capture. The ambitious William M. Connolley set out to define science and what a scientist does in a recent post. Definitely worth reading, especially if you are not that familiar with science. Disclaimer: not surprisingly, the aim was not completely achieved.

Psycho analysis

A classical example for Popper of a non-scientific hypothesis would be Freud's psycho-analysis. The relationship between the current psychological problems of a patient and what happened long ago in the patients childhood is too flexible and not sufficiently well defined to be science. That does not mean that what happens to a child is not important, there are many modern findings that point into that direction (Joachim Bauer, 2010). If someone else would succeed in making Freud's ideas more specific and falsifiable, it would even be a valuable contribution to science. It also does not mean that psycho-analysis does not help patients. Finally, it also does not mean that it is wrong, rather it means that it is not even wrong. It is too vague.

Morphic fields

Another example is the idea of Rupert Sheldrake about morphic fields. Sheldrake claims that when an idea has been invented before, it becomes easier to reinvent it. He has a large number of suggestive examples where this seems to be the case. Thus there is a lot of information to validate his idea.

The problem is, it is impossible to falsify the idea. This idea is, again, too vague and if you do not find the effect in an experiment, you can always claim that the effect is smaller, that the experiment was not sensitive enough or not well executed.

When I was studying physics in at Groningen University, Sheldrake gave a talk and afterwards naturally got the question whether his ideas were falsifiable. He dogged the question and started about the science philosophy of Thomas Kuhn on paradigm changes that shows that in practice it can be hard to determine whether an idea is falsified. However, whether an idea is falsifiable is clearly another question as how falsification works, which will be discussed below. Then Sheldrake started fueling tribal sentiments, by complaining that only physicists would be allowed to have hypotheses with fields, why not biologists? Discrimination! As the climate "debate" illustrates, adding some tribal conflict is an effective way to reduce critical thinking.

This does not mean that the ideas of Sheldrake may not turn out to be valuable. The list of examples that validate his ideas is intriguing. This may well be a first step towards making a scientific hypothesis. That is also part of the work of a scientist, to translate a creative, fresh idea you got during a hike into a solid, testable scientific idea. Morphic fields are, however, not yet science.

Anthropogenic global warming

The hypothesis that the man-made increases in the concentration on greenhouse gasses leads to an increase in the global mean temperature can be falsified and is thus a scientific hypothesis. There is no need to go into details here, because Hans Custers just wrote an interesting post, "Is climate science falsifiable?", which lists ten ways to falsify the "AGW hypothesis". One would have been sufficient.

A clear example is that if the average world temperature drops one degree, back to values before 1900 and stays there for a long time without there being other reasons for the temperature decrease (e.g. volcanoes, sun, aerosols) the theory would be falsified. To get to ten ways, Custers has to come up with rather adventurous problems that are extremely unlikely because so many basic science and experiments would need to be wrong.

Seen in this light, the climate ostriches are almost right, it is highly unlikely that the theory of man-made global warming will be refuted, that would require highly surprising new findings and in most cases it would require basic physics, used in many sciences, to be wrong. However, just because it is highly unlikely in practice that the hypothesis will be falsified because there are so many independent lines of evidence and the hypothesis is well nested into a network of scientific ideas, that does not make it theoretically impossible, thus AGW is falsifiable.


It doesn't matter how beautiful your theory is, it doesn't matter how smart you are. If it doesn't agree with experiment, it's wrong. Richard P. Feynman

This quote is a favorite one of the climate ostriches. Unfortunately, falsification is a little more complex in practice.