The middle ground

Matt Ridley has been complaining about the frantic polarising on Twitter since his talk. When it was pointed out that frantic polarising is a euphemism for ‘lots of people disagree with my argument’, he responded with

no it’s not. I point out that there’s a deliberate attempt to keep the debate binary and deny the middle position cd exist.

What he’s seems to be referring to is a claim he made in his lecture. He claims that

These days there is a legion of well paid climate spin doctors. Their job is to keep the debate binary: either you believe climate change is real and dangerous or you’re a denier who thinks it’s a hoax.

But there’s a third possibility they refuse to acknowledge: that it’s real but not dangerous. That’s what I mean by lukewarming, and I think it is by far the most likely prognosis.

Well, the only reason what he suggests isn’t strictly binary is that he’s added a third option; it, however, is still discrete. It makes no more sense to acknowledge that it’s real but not dangerous than it is to accept that it’s real and dangerous; neither position is consistent with the evidence. As Stoat has said if you can’t imagine anything between “catastrophic” and “nothing to worry about” then you’re not thinking. There are a range of possible outcomes for a given emission pathway, and there are a range of possible emission pathways; the latter, of course, being something over which we have some control.

By and large, the impact will depend on how sensitive our climate is to changes, and how much we end up emitting. There may well be some positive impacts, but it is widely accepted that there will be costs associated with adapting to the changes. There will also be costs associated with reducing emissions, assuming that we decide to actually do so. Suggesting that the options are “not real”, “real but not dangerous”, and “real and dangerous” ignores that there is a continuum of possibilites, some of which we can do something about (our emissions) and some of which we can’t control (climate sensitivity).

The real discussion should take into account the likelihood of the various outcomes, and what we should, or should not, do to address this. Ridley’s position seems like an ironic strawman. Providing one additional option is hardly avoiding the debate remaining binary, especially if this alternative is barely different to one of the other options – there’s not much of a difference between denying that it’s real, and denying that it could be dangerous. Also, most of those he’s criticising don’t – from what I’ve seen – believe that climate change is real and dangerous; they think that it is real, that there is a possibility of severe negative impacts, and that we should consider doing something to avoid these.

If Ridley really wants an improved debate he should at least consider the criticism levelled at him and should avoid doing precisely what he’s accusing others of doing. Of course, I seriously doubt that he is interested in improved debate; that would require acknowledging some of the other possibilities, and that doesn’t appear to be something that he’s willing to do.

Posted in Climate change, ClimateBall, Policy, Research, Science, The scientific method | Tagged , , , , | 174 Comments

Another 97%

In a previous post I mentioned that Richard Tol had published a paper on the structure of the climate debate. As I said in that post, the paper appears to be trying to portray the author as part of some sensible middle, which – given their association with the GWPF – is clearly nonsense, and I’m not quite as optimistic that climate change is a relatively small problem that can easily be solved, but I largely agree with the basic suggestion that [f]irst-best climate policy is a uniform carbon tax which gradually rises over time.

In a Cliscep post that discusses this paper, Richard Tol, however, suggested that should be seen as a blog that set[s] an example for other climate blogs. Well, given that calling themselve Climate Skepticism is overly generous, and given that the tone of their site would be regarded by many as extremely poor, it was rather surprising that someone who felt capable of discussing the structure of the climate debate would regard as an exemplar. Of course, it appears that Richard’s judgement is based more on how he feels he is treated, than on any actual assessment of the quality of the blog itself.

However, just for fun, I ran a poll on Twitter asking if people agreed, or disagreed, that should be seen as an exemplar. The result of my poll is below. As you can see, 97% of those polled disagreed with Richard’s suggestion that is a blog that is setting example that others should aim to follow. Given who made the suggestion that it was, this would seem to be a very apt result😉 .

P.S.: Just to be clear, my Twitter followers almost certainly have a certain bias, so there is probably a large selection effect here, and only 37 took the poll, so only 1 actually agreed with Richard’s suggestion. It is, however, amusing that the result turned out as it did.

Posted in Climate change, ClimateBall, Satire, Science | Tagged , , , , , , | 43 Comments

Matt Ridley’s lecture

I thought I might make some points about Matt Ridley’s recent lecture. There are two general points I want to make. Matt Ridley might have a PhD (DPhil technically) and he might have published some papers in the 1980s, but his expertise is really in business, the banking sector, journalism and politics. He has no obvious expertise that suggests that he is capable of interpreting the evidence associated with climate science himself. And, yet, that is what he does and appears to stick with his interpretations even if the authors of the studies he’s using disagree with what he is saying. Climate science is actually a very complex topic that includes many different research areas. The idea that one person is capable of independently interpreting all this evidence is rather remarkable.

The other point I was going to make is that if someone has to tell you what they aren’t, or what they are (for example, “I’m not a science denier, I’m a lukewarmer”) then either they aren’t conducting themselves in a manner that makes this obvious, or the people labelling them are simply wrong. In my view, they should either consider behaving in a manner that makes it more obvious, or they should largely ignore those doing the labelling; telling people is unlikely to have much impact.

As far as Matt Ridley’s actual lecture, it’s a bit of a gish gallop of “skeptic” talking points. Dana’s already covered some of it in his Guardian article, and Mat Hope has an article on DESMOGUK. The lecture starts with a discussion of the benefits of global greening due to enhanced CO2. The author of the study – who Ridley accuses of delaying publication to avoid it being in the recent IPCC report – has already responded. He disagrees with Ridley’s interpretation, but according to Richard Tol, Ridley has somehow been vindicated. Quite how Tol would know is beyond me.

He then discusses the consensus, saying

The supposed 97% consensus, based on a hilariously bogus study by John Cook, refers only to the proposition that climate change is real and partly man-made.

I presume the “hilariously bogus study” is also Tol as is – probably – the completely incorrect interpretation of the study. It is quite remarkable that someone who has spent so much time responding to this study, still doesn’t understand it. The consensus was not “real and partly man-made”, it was “humans are causing global warming”. When there are two possible causes (humans and not humans) a conclusion that one of them is causing global warming would seem to be somewhat stronger than simply partly causing it.

Ridley then claims that

James Hansen in 1988 said that by the year 2000, “the West Side Highway will be under water.

Well, this is simply not true. In an interview James Hansen was asked, in 1988, what the view out of his office window would be like in 40 years time if CO2 had doubled. Not only is 2000 not 40 years after 1988, the question was also based on the hypothetical scenario of CO2 having doubled.

Ridley moves on to claim that “The climate models have failed to get global warming right”, and illustrates this by showing two figures comparing models and observations. He, however, fails to discuss that the forcings have not been updated, that one should ensure that the models and observations are baselined properly, and that one should ensure that the comparison is actually like-for-like (by accounting for coverage bias and that the observations mix sea surface temperatures and air temperatures). If you do that, then you get quite a reasonable comparison between the models and the observations.

Ridley also claims that the best evidence indicates that climate sensitivity is relatively low. Well, this is obviously subjective and there are many reasons to be cautious of the studies that return low climate sensitivities. Also, these studies still return 5 – 95% ranges of around 0.8oC to 3.1oC. Additionally, if you account for coverage bias and that observational temperatures are a mix of sea surface temperatures and air temperatures, these apparently low estimates turn out to be consistent with most other estimates.

I probably don’t need to say very much more. It’s clear that this was not simply Ridley giving a lecture about climate policy, it was him giving a lecture about his interpretation of climate science, and – in the process – insulting scientists individually (Ranga Myeni and Richard Betts, for example) and collectively, suggesting that

the climate science establishment has a vested interest in alarm.

I’m very interested to see how the Royal Society will respond to this. My guess is that they’ll either do nothing or, if they do respond, it will be completely ineffective; it’s not easy to effectively respond to something quite this off the wall.

Update: Daily Kos has also covered the lecture, and some of the articles about it.  Delingpole’s response is so remarkable, that I can’t bring myself to link to it.

Posted in Climate change, Climate sensitivity, ClimateBall, Greenhouse effect, IPCC, Policy, Politics, Science | Tagged , , , , , , , | 130 Comments

Like a Boss

like-a-bossJim Steele struck again at Judy’s: after walrus science and coral bleaching, he audited Gaia herself. In the walrus episode, I made around 50 comments; Brandon Gates spent 75 in the bleaching one. The Gaia episode features 20 or so, most shorter and more expedient than the ones in the first two episodes.

The key to the reduction was to focus – my previous experience with Jim made me expect that he’d contradict everything I’d say over and over again. Since Jim’s obduracy creates some kind of fixed point, it helps when one’s commitments are both minimal and amusing.  There’s no downside to follow this ClimateBall ™ advice as a general principle. Everything you say can (and will) be never endingly challenged, so you might as well limit your commitments and enjoy defending them.

My first comment thus consisted in quoting Jim’s

There is also ample evidence that lower pH does not inhibit photosynthesis or lower ocean productivity (Mackey 2015). On the contrary, rising CO2 makes photosynthesis less costly.

and to quote Mackey 2015’s abstract, with an emphasis on the following sentence: This could suggest that the photosynthetic benefits of high CO2 are minor relative to the cell’s overall energy and material balances, or that the benefit to photosynthesis is counteracted by other negative effects, such as possible respiratory costs from low pH.

Mackey 2015 fails to support Jim’s claim about CO2 and photosynthesis. (Besides, citing a lone paper fails to prove an inexistence, and positing linear relationships clashes with Gaia theories.) Instead of acknowledging that his hypothesis went beyond Mackey 2015, Jim (a) told me to read the paper, (b) accused me of cherrypicking one sentence, and (c) challenged me to provide a list where Mackey says rising CO2 has been detrimental to photosynthesis.

None of these attacks counter my point, i.e. the very mundane observation that the first sentence quoted doesn’t substantiate the thesis Jim puts forward in the second. Many players may (and will) try to challenge things you haven’t said or done. This can be done by trying to turn the discussion about you, e.g. (a); making baseless accusations, e.g. (b); burdening you with commitments you don’t have, e.g. (c). Jim follows a long ClimateBall tradition, and his playstyle shares affinities with Brave Brandon’s. Incidentally, both rather enjoy lulzing.

It costs very little to sidestep these overburdening attempts. A boss may ignore them all. However, returning monkey wrenches back can also be rewarding. I chose to follow through “you cherrypicked,” because it could help clarify my commitment, but also because it’s kinda silly. So I quoted the relevant paragraph from Mackey 2015’s conclusion, this time with no emphasis:

Photosynthetic responses to enhanced CO2 under OA are remarkably diverse, and variability exists both between and within taxonomic groups (Figure 2). As the substrate for photosynthesis, elevated CO2 would be expected to increase photosynthetic rates either directly by relieving carbon limitation or indirectly by lowering the energy required to concentrate CO2 against a smaller concentration gradient. Nevertheless, despite the growing body of literature on the topic, clear trends in the photosynthetic responses of phytoplankton to elevated CO2 have not emerged, and the positive effects, if any, are small (Figure 2). Additionally, many studies finding “no effect” of OA are likely not published, resulting in a bias in the literature. That no significant difference is apparent even in light of this bias suggests the net effects of OA on photosynthesis are minor for a large proportion of phytoplankton species. The small effect could indicate that the benefits afforded by high CO2 are small relative to the cell’s overall energy and material balances. Alternatively, the small effect of OA could indicate that its expected benefit to photosynthesis is counteracted by other negative effects, such as possible respiratory costs from low pH. Moving forward in OA research, experiments should encompass a broader suite of measurements to probe how different physiological processes in addition to photosynthesis respond to OA.

I also tweeted the Figure 2 into the thread:

The cherrypicking accusation can’t hold – I’m not distorting what the authors are saying. It doesn’t parry the simple point that one does not simply cite a paper that says CO2 doesn’t make photosynthesis less costly in any significant manner and then claim that CO2 makes photosynthesis less costly. At least insofar as one would like to make that thesis significant.

Jim’s only response in that sub-thread was to misread a comment that wasn’t directed at him. Of course he persisted in perpetrating (a)-(c) above elsewhere in the comments, not without trying to mitigate his own well poisoning by echoing the chamber’s sentiments and by throwing some other squirrels.

The most expedient way to meet my point would have been for Jim to own his thesis. All he had to do, then, was to amend his text to clarify that, in contrast to Mackey 2015, he himself argues that CO2 makes photosynthesis less costly. Then would follow some arguments to that effect, preferably not mere handwaving toward Gaia.

That would have met the criticism like a boss.


There are three other exchanges between me and Jim in that episode. They more or less follow the same pattern. Let’s end this note with my second contribution, which underlined that Jim’s

It has been estimated that without the biological pump, pre-industrial atmospheric CO2 would have out gassed and raised atmospheric CO2 to 500 ppm, instead of the observed 280 ppm.

cites what I believe is a preprint to an encyclopedic entry, which itself cites Maier-Reimer 1996. Citing a secondary source for something like an estimate is suboptimal. I don’t know why Jim did this, nor do I care to know. Jim’s motivations are none of my concerns.

Here again, instead of taking that criticism like a boss, Jim accused me of dishonesty. To meet that criticism like a boss, all Jim needed to do was to correct one single URL.

Nevertheless, hours of frenzied ClimateBall can save minutes editing.

Posted in ClimateBall, Sound Science (tm) | 9 Comments

The Royal Society and the GWPF

A couple of weeks ago, it came out that the Royal Society had hired space for an event being run by the Global Warming Policy Foundation (GWPF). The event turns out to be a lecture by Matt Ridley, who I have written about before (I’ve also written about the GWPF before too).

It appears that, despite pressure to cancel the event, the Royal Society is allowing the event to go ahead. Apparently, instead of cancelling the meeting,

“some scientist experts will attend the meeting and keep check on the accuracy of the statements.”

Greg Laden, has responsed positively to this, suggesting that the Royal Society is putting the GPWF on notice. Possibly, but I think the Royal Society is making a mistake. I think they’re falling into the same trap into which I fell when I first started discussing this topic.

I naively thought that a solid explanation of someone’s error would either convince them they were wrong, convince others that they were wrong, or – possibly – both. I have since found that such an outcome is extremely unlikely, if not virtually impossible. Most who present scientifically incorrect arguments are unlikely to be convinced of their errors, especially if their errors have been highlighted many times in the past (as is the case with Matt Ridley). Also, as long as they sound convincing, most who accept their arguments are unlikely to change their minds.

Even if some expert scientists do attend the meeting to keep check on the accuracy of what is said, I doubt it will have a positive outcome. Either they will be ineffective and the GWPF will be able to imply that they had a meeting “hosted”, or maybe even “endorsed”, by the Royal Society, or they will try to counter what is presented at the meeting, and the GWPF will complain about being censored and will probably suggest that the Royal Society is behaving unscientifically. The GWPF will manipulate it, whatever happens. You may notice that I haven’t considered the possibility that what will be presented will actually be scientifically accurate. Well, that’s because that would be silly.

I’m not suggesting that the Royal Society should go ahead and cancel the event, as that would be manipulated by the GWPF too. I don’t actually think that there really is a positive way out of this at this stage (the meeting is in 2 days times). However, given their past encounters with the GWPF, you would think that they would have thought twice about hosting the event in the first place. Maybe they think that they can effectively counter any misrepresentations, but I suspect that they don’t fully appreciate how manipulative the GWPF can be. I may well be wrong, and would be perfectly happy if it turns out that I am.

Anyway, since I’m discussing the GWPF, I might as well advertise a recent paper about the structure of the climate debate, by one of their Academic Advisors. It’s actually mostly quite sensible. I’m not quite as optimistic that climate change is a relatively small problem that can easily be solved and it, of course, tries to portray the author as part of some sensible middle, which – given their association with the GWPF – is clearly nonsense. However, I largely agree with the basic suggestion that [f]irst-best climate policy is a uniform carbon tax which gradually rises over time.

This is getting rather long, and it’s about all I had to say. Comments welcome.

Posted in Climate change, ClimateBall, Global warming, Science | Tagged , , , , , , | 199 Comments

Guest Post: Post-Factual Perceptions of Weather

Adversarial interactions between physical and social scientists are sometimes seen around this blog, so I’m happy to report on something different. The occasion is a new paper in the 50th anniversary issue of Sociology, flagship journal of the British Sociological Association. The first author is a sociologist, the second a climatologist, the third a geographer, then two more sociologists.

Flood realities, perceptions and the depth of divisions on climate” employs both physical and social data, as its title suggests. It focuses on the northeastern US state of New Hampshire, where destructive flooding increased in the past decade, for reasons partly related to climate. Figure 1 depicts this increase in terms of disaster expenditures and newspaper reports, but our paper also presents river flow and precipitation data that tell the same story.


Figure 1

Might this increase have been noticed by the public, especially in the most affected areas, overshadowing people’s ideological beliefs about climate change? That hopeful hypothesis, posed by climatologist Cameron Wake, is what launched our study. But statewide surveys in summer and fall 2015, involving more than 2,000 telephone interviews, found surprisingly low public awareness. We asked,

Comparing the past 10 years with 20 or 30 years ago, do you think that number and size of destructive floods in New Hampshire have increased, decreased or stayed about the same?

Over the next few decades, do you think that number and size of destructive floods in New Hampshire are likely to increase, decrease or stay about the same?

Figure 2 graphs responses, along with the observed frequency of extreme precipitation events for the decades in question. Only 35 percent of our respondents thought (correctly) that floods in the past decade had increased.


Figure 2

Moreover, careful analysis found no indication that either past or future flood responses are systematically higher in counties that have been most affected, or are most vulnerable. Disappointingly, responses to the flood questions instead exhibit strong ideological gradients, all too familiar for just about anything related to climate. Figure 3 depicts these gradients for our two flood questions and also a standard question about climate change, which correlates so closely with ideology that it could provide an alternative measure.


Figure 3

These results on New Hampshire flooding are, unfortunately, not a fluke. Another recent study, also with an interdisciplinary team, focused on northeast Oregon (“Wildfire, climate, and perceptions in northeast Oregon”). In that rural region, summer warming has been accompanied by a dangerous rise in wildfires. We found a similar pattern: public awareness of the warming trend follows a party-line gradient, and is mostly unrelated to experiential factors such as long-term residence or ownership of forest land.

Both of these studies involve decadal trends, however. To learn whether similar patterns affect recollections of recent weather, without mentioning trends, New Hampshire State Climatologist Mary Stampone and I carried out an experiment described in “Was December warm?” December of 2015 had been the state’s warmest by far, for that month or any other (in anomaly terms) looking back more than a century. The whole winter of 2015–16 set historical records as well. Asked about December on a statewide survey in February, or about the winter on a second survey in April, most people correctly said temperatures had been above average. But this accuracy was significantly higher among Democrats, and those who think humans are changing the climate.

We repeated our question a third time on a survey in July. The election campaign was by then in full swing, so we can make a more topical comparison. Trump and Clinton supporters stand 21 points apart in their recollections about the record-setting winter (Figure 4). Political divisions seen earlier had apparently widened as winter became a few months more distant.


Figure 4

While political resistance to climate science in the US appears intractable at times, some observers hope that nature will intervene more persuasively, giving inescapable signs of a problem. For scientists, it has done so already, but many people do not take their word for it, or yet see the problems themselves. That ideology or partisan social identity filters public perceptions about disasters and even mundane weather so powerfully suggests that this process, if it happens, won’t be quick.

Posted in Uncategorized | 36 Comments

Thinking like a planet

Adam Frank has a recent article called Climate change and the astrobiology of the anthropocene. The premise of the article is that we should think of climate change in terms of astrobiology and, in particular, the habitabilty of planets and the sustainability of civilisations that may evolve. Given that my own research interests are in exoplanets, and how planets form and evolve, I do find the it interesting to think of climate change in a broader context.

The article made some interesting points. Current exoplanet statistics suggests that it’s extremely unlikely that we are the only technologically advanced civilisation to have ever developed. The article also discusses work that considers how advanced civilisations may evolve and influence the planets on which they exist – in our case moving us from the Holocene to the Anthropocene, an entirely new geological epoch dominated by our activity. Using large amounts of energy for civilisation building has to influence the planetary habitat and the issue is if this can be sustained or ultimately leads to collapse.

However, I thought the framing at the end of the article was rather unfortunate. The article ends with

we are simply another thing the Earth has done in its long history. We’re an “expression of the planet,” as Kim Stanley Robinson puts it. It’s also quite possible that we are not the first civilization is cosmic history to go through something like this. From that perspective, climate change and the sustainability crises may best be seen as our “final exam” (as Raymond PierreHumbert calls it). Better yet, it’s our coming of age as a true planetary species.

We will either make it across to the other side with the maturity to “think like a planet” or the planet will just move on without us. That, I believe, is the real meaning of what’s happening to us now. It’s a perspective we can’t afford to miss.

I agree that we’re not a plague, that we should think about ourselves as an integral part of the planet, and that the planet will carry on with, or without, us. However, overall, the above makes it seem as though the whole process is simply natural and, hence, something that we cannot control. If we were simply observers watching the evolution of many different advanced civilisations, this might be a reasonable way in which to think of this, but we’re not; we are the civilisation that is fundamentally changing the planet on which we depend. We are not only aware of the implications of our actions, but can also make decisions about what we do and can actively try to influence the outcome; we can aim for sustainability rather than collapse.

I don’t know if the intent was to make it sound like a natural process over which we have no control (my impression is that it was not), but I think that that is one way in which this argument could be perceived. So, although I have some sympathy with the idea of thinking in terms of us being a planetary species, I do think that we should be careful of framing it in a way that makes it seem as though we’re just observers watching as our civilisation either collapses or attains sustainability.

Posted in Climate change, ClimateBall, Global warming, Science | Tagged , , , , , | 200 Comments