Science is broken!

There’s been quite a lot in the media, and elsewhere, about problems with science. A common theme at the moment is the replication crisis, but you regularly see claims in the blogosphere that papers should be retracted because they supposedly have errors, and I’ve even seen some argue that we should find ways to penalise scientists who misrepresent our current understanding.

I’m a bit tired, and can’t really face writing anything too lengthy (I may fail) so thought I’d make some basics points and let others express their views in the comments. It’s clear that some of the criticisms have merit. We should promote good practice and should encourage people to publish research that is careful and thoroughly checked. What we value (lots of grant funding and papers in Nature, for example) does not always reflect actual quality. We should publish negative and null results and should aim to also publish replication studies. We could improve how we undertake peer-review.

However, science (by which I really mean fundamental research) is about understanding things, typically things we don’t yet understand fully. People should take risks; that’s how we solve interesting problems. People will get things wrong; it’s part of the process. People will try methods that turn out not to be very good; again it’s part of the method. We should encourage people to challenge existing paradigms, even if what they do ends up being horribly wrong – the quality of the challenges can tell us something of how hard it is to overthrow well-established ideas. We should base our understanding – or lack thereof – on an assessment of all the available evidence, not simply on one, or two, studies.

In some sense, that seems to be where some of the problems lie. In normal science, we trust our overall understanding when there is a large collection of consistent evidence. In some cases, however, important decisions are based on one, or a few, studies. When these turn out to be wrong, the impact can be substantial. In my view, however, this is not normal science; we shouldn’t be basing our understanding on only a few studies. Sometimes, it may be unavoidable, but we should still be careful of judging science overall, on the basis of a few examples like this.

Maybe in cases like this (when we do need to make decisions with limited evidence) we should scrutinise the evidence more carefully. In normal science, however, I would still favour trusting the method, rather than encouraging detailed scrutiny of individual studies (nothing wrong if people want to do this, but I don’t see the overall value). That doesn’t mean that there aren’t things that we could do to improve the overall quality of research, just that the problems are not – in my opinion – nearly as great as might be indicated by some of the examples that are often given.

Anyway, that’s a summary of my general views. If anyone else would like to add anything, or make a different argument, feel free to do so through the comments.

Posted in ClimateBall, ethics, Research, Science | Tagged , , | 107 Comments

The BBC and its balance, again

I had been struggling to find things to write about, but I listened this morning to the Today show on BBC Radio 4. It included an interview with David Hempleman-Adams, expedition leader of the Polar Ocean Challenge, which has successfully transited both the North East and North West passages; circumnavigating the North Pole in a single Arctic summer.

Even though he was clearly concerned about the reduction in Arctic sea ice, and highlighting this was clearly one reason for the expedition, he was also clear that they aren’t scientists and that you can’t infer too much from their expedition. Their intent was really to encourage people to pay more attention to what scientists are saying about the Arctic and, in particular, Arctic sea ice. It was all going well, and then the interviewer said:

… the well-known science writer, Matt Ridley, has written about your expedition and said, look, there are times in the past where, routinely, ice has disappeared during the summer, and his argument is that really, it doesn’t matter, it doesn’t actually tell us anything.

Why Matt Ridley, and why should we care what he thinks? He doesn’t have any expertise that would suggest his view carries more weight than those of anyone else. Also, he may be a well-known science writer, but he’s also a Viscount, a member of the House of Lords, the ex-Chairman of Northern Rock, and Academic Advisor to the Global Warming Policy Foundation, and has coal mines on his land. Referring to his simply as a well-known science writer would seem to be ignoring many other relevant descriptors.

Matt Ridley’s views on Arctic sea ice appears to come from an article he wrote for the Times called an ice-free arctic ocean has happened before. His basic point is that the Arctic has been ice-free in summer before everything was fine. He concludes with

The effect on human welfare, and on animal and plant life, will be small. For all the attention it gets, the reduction in Arctic ice is the most visible, but least harmful, effect of global warming.

Really? No caveats. Absolute certainty. The effect will be small and it will be the least harmful effect of global warming. How can he possibly know this? He can’t even write like a scientist and we’re supposed to take his views seriously?

What about his sources? Well, he provides none for his absolutely certain conclusions, but earlier in his article, he does say

It seems that the quantity of Arctic sea ice varies more than we used to think. We don’t really know how much ice there was in the 1920s and 1930s — satellites only started measuring it in 1979, a relatively cold time in the Arctic — but there is anecdotal evidence of considerable ice retreat in those decades, when temperatures were high in the Arctic.

Where does his anecdotal evidence come from? Why, it comes from Anthony Watts and Steven Goddard, two people who have contributed significantly to the promotion of science denial. I know Matt Ridley objects to being regarded as a science denier, but it is hard to see why; if he really doesn’t like it, maybe he should stop getting his information from sites that are clearly promoting science denial. If you want a more reliable source, you could try this, which says:

The consolidated database shows that there is no precedent as far back as 1850 for the 21st century’s minimum ice extent of sea ice on the pan-Arctic scale.

So, in an interview with someone who undertook an expedition so as to encourage people to listen more to what scientists are saying about the Arctic, the BBC manages to introduce the views of Matt Ridley, an advisor to the Global Warming Policy Foundation and someone who gets their information from sites that promote science denial. Could it have been more ironic?

Posted in Climate change, Global warming, Science, Watts Up With That | Tagged , , , , , , | 59 Comments

Weather, or climate change?

I start teaching again tomorrow, so it’s going to be a busy few months and posting will probably be light. I also don’t really have much to say at the moment, but that will probably change🙂. I did, however, want to post this video that I found recently (see below). It discusses the link between weather events and climate change. It includes Kevin Trenberth making the point that the environment in which all events occur is different today, than it was in the past. Consequently, every event is different.

What I particularly like about the video is that those being interviewed regularly refer back to basic physics; evaporation, energy, increasing water vapour in the atmosphere, etc. We do have a very good understanding of the basic physics associated with climate change. Just because we have not definitely found some signal in a dataset, does not suddenly bring this understanding into question. Of course, if we would expect to have seen a signal, and do not, it might. Not seeing something in incomplete, or noisy, data does not.

Of course, there are certain aspects that are complicated and where the impact of climate change may not be obvious. There are others, however, where it would be extremely surprising if climate change did not increase the frequency and intensity of the most extreme events; as Kevin Trenberth says “at the high [is] when you start breaking records”. Maybe I’m biased, but I think it’s important to realise that our basic understanding of the underlying physics is very strong and that gives us a very good understanding of what – in general – we might expect. I’ll leave it there, and I recommend watching the video.

Posted in Climate change, ClimateBall, Global warming, Greenhouse effect, Science | Tagged , , , , , , , , | 77 Comments

Engineering the software for understanding climate change

Since Judith Curry has a guest post about global climate models and the laws of physics, I thought it would be worth posting this recently released video of a talk about climate modelling (see below). It’s by Steve Easterbrook, who is a Professor in the Department of Computer Science at the University of Toronto.

One problem with blogosphere critiques of climate models is that it often seems to come from those who might have some relevant expertise, but who have never actually run a climate model, or spent any significant amount of time talking with those who have. They also seem to base their critique on things they’ve read on the internet and – as a result – assume climate modellers do not understand some pretty fundamental things; ignoring that online material about climate models, aimed at the general public, will clearly not include the kind of details that you will find in the scientific literature. Additionally, they assume that climate modelling should be conducted in a manner similar to what they themselves might have experienced, ignoring that what might work in one field, might not in another.

What Steve Easterbrook did was spend a lot of time at the UK’s Met Office, interacting with – and learning from – those who do run, and develop, climate models. He found that there are reasons why climate modellers might behave differently to software engineers, or those doing computational modelling in industry. Climate models are scientific instruments. The goal is not to design a new climate, or produce some specific product; the goal is to understand our climate, and how it might respond to changes. He also discussed how they continually test the models and how there are very few defects, per thousand lines of code. His argument for this being that in such a code, it can be fairly obvious when there is a problem, and therefore you can find, and fix, defects more easily than might be the case in other codes.

I don’t think I need to say much more. The talk is a little long, but it’s certainly worth watching. Steve Easterbrook’s blog is also very good, and has a number of posts about climate models.

References:
The talk is – I think – from 2011, but has only just been released. As Victor Venema points in the comments on youtube, the paper on which it is based is here.

Posted in ClimateBall, Global warming, Judith Curry, Research, Science | Tagged , , , , , , | 45 Comments

Why I find it difficult to discuss climate policy

I generally try to avoid discussing climate policy specifically. One obvious reason is that I don’t have any particular expertise in that area, or any special insights. However, there is a somewhat subtler reason as to why I find it a difficult topic. When I read something like this post about carbon taxes (which I discussed here) it makes a lot of sense. There are lots of factors to consider. If we do too much now, the current generation could pay much more than their fair share, and we could do more harm than good. If we do too little now, we could pass on too much to future generations. It’s a difficult balancing act.

Then I start to think a bit more like a physicist. Our climate is a complex, non-linear system. We have the potential to change it substantially, and to do so very quickly. We could change our climate by an amount comparable to the change between a glacial and an inter-glacial, but could do so ten times faster than has occured in the past. For small changes, we expect the response to be linear, and maybe it will remain linear even if we induce what is quite a large change. On the other hand, maybe not; it’s not impossible that it could flip into some kind of new state. Maybe such a new state would be beneficial. However, I would guess that the region of parameter space in which changes would be beneficial is dwarfed by the region of parameter space in which it would be very detrimental.

On top of being a physicist, I’m also involved with finding planets around other stars. This makes me very aware of the fact that the only place in the universe where we know life to exist is on our own planet. In fact, the only place is in a very thin shell around our planet. What makes this planet habitable is our atmosphere, into which we’re currently dumping CO2 like there’s no tomorrow. Even if there is life elsewhere – as there probably is – it also doesn’t really make any difference; this is our home for the foreseeable future. Treating our atmosphere like a waste dump, seems like a really bad idea.

So, of course I think that dumping giga-tonnes of CO2 into our atmosphere and pushing our climate hard and fast is something we should probably avoid doing, but how? I just end up back at the beginning again; just because we should probably not be dumping giga-tonnes of CO2 into the atmosphere doesn’t mean that it’s easy to work out how best to not do so. There are clearly many factors to consider. However, ignoring – or even dismissing – that what we’re doing carries risks and is probably unprecedented, doesn’t appear to be an effective way of encouraging that we take this seriously and actually start doing something substantive. It’s why I find myself getting frustrated by some of the social science comments on this topic; they seem to often ignore what makes this an issue worth taking seriously.

Anyway, I’m not really sure where I’m going with this. I guess it’s that climate policy (by which I mean what we should decide to do) is a very difficult and complicated issue. On the other hand, deciding whether or not we should actually do something, doesn’t seem all that complicated; to me, at least.

Posted in advocacy, Climate change, ClimateBall, Policy, Science | Tagged , , , | 69 Comments

The attribution question

It seems as though the issue of trying to attribute an anthropogenic influence to an extreme weather event is controversial on a number of levels. It sometimes seems to divide even those who largely agree, and almost always produces a push-back from those who appear to want to dismiss the risks associated with climate change. Some of this push-back is justified, but some is no better than those who make overly strong claims about an association between climate change and an extreme weather event. Not being able to make some kind of formal attribution does not mean that there is no link between climate change and these extreme events.

My own view is that asking whether or not climate change caused a particular extreme event is silly; we can’t answer that question. What we can do, though, is consider how anthropogenically-driven climate change has influenced the likelihood of certain events. Naively one might argue that in a warmer world we would expect, for example, an increase in the frequency and intensity of heatwaves and extreme precipitation events. This may be reasonable globally, but as this paper by Friederike Otto and colleagues points out, regionally it depends on both thermodynamic changes (more energy) and changes in atmospheric circulation.

To try and understand how climate change is likely to influence extreme events – regionally at least – one therefore needs to consider both warming (thermodynamics) and how it influences the movement of atmospheric patterns (circulation). Circulation changes could reduce the likelihood of some events in some regions, while enhancing it in others. The key point, though, is that this is not an attempt to determine if climate change is causing these extreme events; it is simply trying to establish how climate change influences the overall risk of these extreme event.

I may not have explained this properly, but fortunately the author is on hand to do a better job than I can.

Posted in Climate change, Climate sensitivity, ClimateBall, Research, Science | Tagged , , , , , , | 112 Comments

Our Ethical Web of Beliefs

Last winter, I saw over the tweeter that Lawrence Torcello published a new paper. Paywalled. So I asked him for a copy, using the hashtag #CanIHazPDF:

He sent me a copy in a matter of days. We exchanged a bit. I asked him for a Q&A. Here it is. Trigger warning: my questions (after “[W]“) can make no sense, and Lawrence’s responses (following “[L]“) can make you think.

[W] Let’s start with Clifford’s first thought experiment:

A shipowner was about to send to sea an emigrant-ship. He knew that she was old, and not overwell built at the first; that she had seen many seas and climes, and often had needed repairs. Doubts had been suggested to him that possibly she was not seaworthy. These doubts preyed upon his mind, and made him unhappy; he thought that perhaps he ought to have her thoroughly overhauled and refitted, even though this should put him to great expense. Before the ship sailed, however, he succeeded in overcoming these melancholy reflections. He said to himself that she had gone safely through so many voyages and weathered so many storms that it was idle to suppose she would not come safely home from this trip also. He would put his trust in Providence, which could hardly fail to protect all these unhappy families that were leaving their fatherland to seek for better times elsewhere. He would dismiss from his mind all ungenerous suspicions about the honesty of builders and contractors. In such ways he acquired a sincere and comfortable conviction that his vessel was thoroughly safe and seaworthy; he watched her departure with a light heart, and benevolent wishes for the success of the exiles in their strange new home that was to be; and he got his insurance-money when she went down in mid-ocean and told no tales.

He concludes that it is wrong always, everywhere, and for anyone, to believe anything upon insufficient evidence. I am not sure I’d go as far as Clifford, but I feel there’s something right about the argument in your abstract: [W]e are morally responsible for our beliefs because (a) each belief that we form creates the cognitive circumstances for related beliefs to follow, and (b) we inevitably influence each other through those beliefs.

[L] I don’t endorse Clifford’s final position, which I think is too strong, but I do propose that our beliefs carry a moral hazard. The premises I interpret to undergird Clifford’s argument are enough to support the conclusion that our beliefs have morally consequential implications. Put most simply, our beliefs may lead to harmful consequences for other morally relevant beings that we ourselves may, or may not, be insulated from.

I agree with my fellow philosopher Peter Singer on what it means to be morally relevant, and to act ethically. Any sort of being that is minimally sentient—capable of suffering—is morally relevant. Beings who are capable of suffering have an interest (in not suffering) that from an ethical point of view deserves to be taken seriously. This is not to say that all minimally sentient beings need to be treated equally, but it does imply that acting ethically involves extending equal consideration of interests to all morally relevant creatures.

[W] Thus according to your stance, there is a relationship between morality and knowledge. Does it mean the whole fact/value dichotomy collapses, and that our knowledge establishes both epistemic and moral constraints?

[L] I don’t claim the fact/value dichotomy collapses, but, I do think that our knowledge, and epistemic limitations on our knowledge, can establish moral constraints. Consistent with Clifford’s arguments, our beliefs and our means for gathering evidence in support of our beliefs, carry moral implications. I agree that what we can reasonably claim to know ought to inform our judgments and behaviors—including our ethical decisions. And, yes, our ethical judgments also determine what restrictions we place on gathering information about the natural world (e.g. some human experiments that might be extremely useful in gaining medically relevant information are ethically unjustifiable). All of this follows from first making the decision to care about living an ethical life. However this is a value based decision. To reference an observation made by the early 20th century philosopher G.E. Moore, it remains an “open question” whether or not it is good to embrace such values.

I don’t think we need to overcome the fact/value distinction to get on with ethical decision making. We just have to value living an ethical life. One might respond that the reason we ought to value ethics is based on the fact that human beings need to cooperate with each other in order to survive. Very well, but first we must value survival. Once we commit to living a philosophical life, that is to say, a life in which we accept that beliefs and behaviors should be justifiable (to others as well as ourselves), we have already made an ethical commitment. Still, one must value living a philosophical life to begin with—no one is morally compelled by facts to do so.

[W] Still, Clifford’s argument seems to imply that we can derive an epistemic norm (or at least a meta-norm) out of facts from our cognitive and social reality. If we take the ethics of belief seriously, why shouldn’t we conclude that what we know transfers into what we should do?

[L] To be sure, what we know, or think we know, does inform what we do. It doesn’t follow from this that the fact/value distinction has been overcome. In some ways what we don’t know is equally–if not more–important for ethics than what we know. The epistemological limits of my ability to reasonably justify my actions to others constrains my ethical options. And yet, we can get very far, ethically speaking, just by figuring out what behaviors we can’t justify while equally considering the interests of others. Notice I am using the word justify rather than convince. Not every ethically relevant being is capable of being convinced or will be convinced by normative reasoning. The difficulty of the is/ought distinction is that it raises a challenge for anyone wishing to arrive at a final indisputable normative claim about ethics, that every rational entity qua rational entity is compelled to accept, premised on some natural fact about the world. Aristotle pointed out, over two millennia ago, that it is a mistake to expect ethics to function as a precise science. I agree.

Any claim to overcome the fact/value distinction, in my opinion, is fraught because (1) we can’t have certainty with regard to facts—which is not to say that facts don’t exist, and (2) we can at best inductively infer a moral implication of a perceived fact about the world, but we cannot deduce moral facts from natural facts—because it always remains logically possible for us to be wrong. At the most basic level such inferences would violate the rules of logic. (3) We only care about any of this, if we do, because of our prior valuation of truth and morality.

I suspect that some “lukewarmer” types would like to use Hume’s legitimate caution to bolster their own arguments against ethical calls to address climate change. They are out of luck: For one thing ethics, like science, can provide useful guidance independent of certainty. Not every decision with clear benefits to human health and survival needs to pass strict meta-ethical scrutiny to be of reasonable utility (Hume would agree).

One benefit of recognizing fallibility is that it keeps us from being dogmatic both in terms of facts and values, which to my mind is of great assistance to the self-correcting projects of science and philosophy.

[W] Speaking of which, you say: The scientific process does err, it should be emphasized, but it also self-corrects over time (Merton, 1942, 1973). Again, it is this process of progressive self-correction that relies upon robust genuinely skeptical methodologies. Those who challenge the view that science is necessarily self-correcting, in doing so, can even play a role in the long-term trend of scientific critique and self-correction (Ioannidis, 2012). A nifty way to turn the auditing business on its head: whatever is reliably converging toward truth could in the end be called science.

[L] I think of science as an ongoing process that involves, regardless of the field, a rigorous methodologically skeptical approach to understanding the natural world. The exact methodology used in science differs depending on the field, but the long term process is ultimately one of criticism and scrutiny. It involves the collection of data, the running of experiments, the examination of peer-review, and the open analysis of published results by one’s colleagues, who then, in many cases, test conclusions further through their own research. At each turn scientific hypotheses and findings are subject to skeptical refutation. Science advances, in this way, through organized efforts to disprove conclusions. The process is one that guards against the individual biases of researchers and their social circumstances. This means that by virtue of the process, there will always be errors and false starts. Those errors are not evidence that the process is flawed but signs that the skepticism inherent to the scientific process is working.

Science is self-correcting precisely because of its philosophical foundation in skepticism, which is always toxic for dogmatism. Any one scientist can be sloppy, mistaken — just an all-around poor scientist. This is why the modern scientific process is, and needs to be, a communal effort that involves researchers from different fields all over the world. Something like climate change is first and foremost described and understood by scientists working in climatology, but researchers in fields such as biology (for instance) can provide confirmation of climatological findings through the impacts they detect in their own field. This is how the global community of scientific researchers from various domains converge upon evidence that supports a larger theory, which then adds to our collective human understanding of nature.

[W] So we’re all in one big boat together, both in our values and our beliefs.

[L] We seem to be stuck together, endorsing different values, embracing different beliefs. This isn’t a bad thing, if we are reasonable, we can find ways to work together socially and politically in the context of physical and logical reality. This is why the fact of scientific consensus, by the way, is so important for the layperson to recognize and understand. When a scientific consensus exists it is a signal that a finding has been as thoroughly vetted as human beings know how to vet a finding. Science is a powerful philosophical enterprise. Furthermore, those that critique the scientific process itself, and philosophers of science have been doing this constructively for a long time, contribute to the process by checking the epistemic foundations and logical planks of the scientific structure in order to refine the process. Even those who are politically motivated and ideologically driven to criticize the findings of climate science contribute, insofar as they are able to raise legitimate questions that need to be clarified to the public. Nevertheless, in my experience the latter critics have not made much of a contribution to science other than to provide a lively contrast for comparison to the virtues of actual science.

[W] I must share with you this talk that I found while looking if The Worldwide Web of Beliefs was already taken. I found it very moving. Climate change is mentioned at 16:30:

 

[L] Thanks for sharing this interesting talk. The reality of morally pluralistic groups of people, who may hold beliefs that are equally valid compared to, but incommensurable with, the beliefs of other cultural groups, is one of the things that makes deriving “an ought from an is” so tricky.

Relatedly, the major question that drives my work in moral and political philosophy (independently of climate change ethics) is how we might recognize moral/value pluralism while avoiding ethical relativism.

By the way, the most basic lesson of Clifford is that we cannot avoid the moral implications of our beliefs. Our epistemic beliefs don’t form, or exist, in a moral vacuum.

[W] Can our candid readers haz a copy of your paper?

[L] I’ve added a preprint version to my WordPress page for anyone unable to access the published version. I, of course, am happy to email a copy to anyone that asks.

Posted in ethics, Pseudoscience, Sound Science (tm), The philosophy of science, The scientific method | Tagged , , , , | 154 Comments